LIBRO-CONGRESO-CITRUS

THE XII INTERNATIONAL CITRUS CONGRESS 

“CITRUS AND HEALTH” 

18th-23rd November 2012

WELCOME MESSAGE .................................................................... I/3 

THE 12 TH ICC COMMITTEES ........................................................ I/4 

Honor Committee .................................................................... I/4 

Organizing committee ............................................................. I/4 

Collaborators ............................................................................ I/5 

GENERAL INFORMATION ............................................................. I/6 

SUPPORTERS .................................................................................. I/8 

SPONSORS ..................................................................................... I/9 

SPONSORS advertisments .......................................................... I/10 

SCIENTIFIC PROGRAMME ........................................................... I/17 

ICC 2012 Programme at glance ............................................ I/19 

Scientific programme ............................................................... I/20 

PLENARY CONFERENCES ............................................................. 1 

WORKSHOPS ................................................................................. 11 

SESSIONS: 

Session 01: Citrus germplasm and phylogenetics ................ 25 

Session 02: Citrus genetics and breeding .............................. 35 

Session 03: Citrus genomics ..................................................... 59 

Session 05: Biotechnology ....................................................... 73 

Session 06: Fruit physiology ...................................................... 93 

Session 07: Regulation of growth and development ........... 105 

Session 08: Abiotic stress .......................................................... 115 

Session 09: Postharvest physiology and pathology .............. 131 

Session 10: Watering and nutrition .......................................... 155 

Session 11: Cultural practices and mechanization ............... 175 

Session 12: Citrus HLB and other bacterial diseases ............. 191 

Session 13: Fruit flies .................................................................. 219 

Session 14: Virus and virus-like diseases .................................. 231 

Session 15: Fungal diseases ..................................................... 253 

Session 16: Entomology and pest control .............................. 273 

Session 17: Varieties .................................................................. 303 

Session 18: Rootstocks .............................................................. 321 

Session 20: Citrus and Health .................................................. 341 

Session 21: Postharvest and juice processing technology ... 351 

Session 22: Citrus economics and trade ................................ 365 

AUTHOR’S INDEX .......................................................................... 375

WELCOME MESSAGE 

On behalf of the International Society of Citriculture (ISC) and the Organizing 

Committee I wish to warmly welcome you to the 12th International Citrus Congress 

(ICC 2012) and welcome to the city of Valencia. 

The ICC 2012 is taking place from 18 to 23 November, at the Valencia Conference Center. 

More than 720 scientific contributions will be presented in this congress to highlight the 

advances in citrus research. The Organizing Committee with the collaboration of the 

selected conveners have built a scientific program which will provide a balanced the 

overview among basic and applied citrus research, to be presented in parallel sessions. 

Of special consideration are the seven plenary sessions and the eleven workshops 

focused to look at recent advances and future prospects on specific citrus issues, related 

to the most important scientific and technological problems. The main objective of the 

whole program is to bring together members from the citrus community for a thorough 

and lively discussion on each theme. The program also places a special emphasis on 

the main theme ‘Citrus and Health’ focused from different perspectives. Thus I would like 

to meet you all in these sessions! 

In addition to this exciting scientific program, you will benefit of being in the third 

largest city of Spain. The legacy left by more than 2000 years of different cultures 

and civilizations shape the the city’s monuments and streets, and also their habitants. 

Valencia is a city that never sleeps, with an extensive cultural a lineup start-studded at 

any time of year with festivals, concerts, shows and exhibitions. The excellent climate 

and the attractive cityscape allow outdoors activities as café terraces, seaside 

terraces, parks and garden activities throught all the year. I’m sure that all you will 

enjoy the experience of living Valencia. 

Last but not least, I wish to thank to the Organizing Committee, collaborators, conveners 

and Sponsors for their extraordinary efforts to make the 12 th International Citrus Congress 

possible. 

I expect that the ICC 2012 will be a great scientific success and look forwards to meeting 

all you during these days. 

Dr. Luis Navarro 

President of the ISC 

Chairman of the Organizing Committee of the ICC 2012 

XII INTERNATIONAL CITRUS CONGRESS 2012 - I/3

THE 12th ICC COMMITTEES 

Honor Committee 

ICC Honor Committee President 

His Majesty the King, JUAN CARLOS I 

Members 

Molt Hble. Sr. D. ALBERTO FABRA PART 

President of the Generalitat Valenciana 

Excmo. Sr. D. MIGUEL ARIAS CAÑETE 

Minister for Agriculture, Food and Environment. 

Excma. Sra. D.ª RITA BARBERÁ NOLLA 

Mayoress of Valencia city. 

Excma. Sra. D.ª CARMEN VELA OLMO 

Secretary of State for Research, Development and Innovation. 

Molt Hble Sra. D.ª MARITINA HERNÁNDEZ MIÑANA 

Councelor for Agriculture, Fisheries, Food and Water of the Valencian Community. 

Molt Hble. Sra. D.ª MARÍA JOSÉ CATALÁ VERDET 

Councelor for Education, Training and Employement of the Valencian Community. 

Excmo. Sr. D. ANTONIO CERDÁ CERDÁ 

Councelor for Agriculture and Water of the Murcia Region. 

Organizing committee 

ICC Chairman, ISC President 

Dr. LUIS NAVARRO 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, 

Valencia, Spain. 

ICC Vice-chairman 

Dr. EDUARDO PRIMO 

Centro de Citricultura y Producción Vegetal, IVIA. 

ICC Secretariat 

Ms. TANIA NAVARRO 

Fundación AGROALIMED, Valencia, Spain. 

Scientific Programme coordinator 

Dr. LEANDRO PEÑA 

Centro de Protección Vegetal y Biotecnología, IVIA. 

Publications coordinator 

Dr. BEATRIZ SABATER-MUÑOZ 


Technical tours coordinators 

Dr. PEDRO MORENO 


Dr. SALVADOR ZARAGOZÁ 

Centro de Protección Vegetal y Biotecnología, IVIA.

Members 

Dr. FLORENTINO JUSTE 

Director IVIA 

Dr. MARIANO CAMBRA 


Dr. NÚRIA DURÁN-VILA 


Dr. ALBERTO URBANEJA 


Dr. MANUEL TALÓN 

Centro de Genómica, IVIA. 

Dr. JOSEP A. JACAS 

Universidad Jaume I (UJI). 

Dr. MANUEL AGUSTÍ 

Universidad Politécnica de Valencia (UPV). 

Dr. LORENZO ZACARÍAS 

Instituto de Agroquímica y Tecnología de los Alimentos (IATA). 

Dr. ÁNGEL GARCÍA-LIDÓN 

Instituto Murciano de Investigación y Desarrollo Agrario y Alimentario (IMIDA). 

D. ADRIÁN AGUSTÍ 

Agrimarba SA. 

D. JOSÉ MARÍA PLANELLS 

ANECOOP. 

D. FRANCISCO LLATSER 

AVASA. 

D. FRANCISCO JOSÉ MARTÍNEZ 

Comité de Gestión de Cítricos. 

Collaborators 

Dr. ANTONIO VICENT 


Dr. GEMA ANCILLO 


D. JOSÉ JUÁREZ 


Dr. PABLO ALEZA 


Dr. MARÍA ANGELES FERNÁNDEZ 


Dr. MARÍA ANGELES FORNER 


D. PABLO LEMOS 

Sección Informática, IVIA. 

D. FRANCISCO ARENAS 

Consejería de Agricultura de la Junta de Andalucía. 

Dr. JOSÉ IGNACIO PORRAS 

Instituto Murciano de Investigación y Desarrollo Agrario y Alimentario (IMIDA). 

Dr. M.ª CARMEN VIVES 



GENERAL INFORMATION 

The city of Valencia 

Located in the eastern coast of Spain, Valencia has a population of 800.000 inhabitants, 

being the third largest city of Spain. This location is the responsible of the mild temperate 

Mediterranean climate observed in the city, with an average annual temperature of 17ºC 

with warm summers and very mild winters. The rainfall period is at the beginning of spring 

and in autumn. 

There are two official languages in Valencia, the Spanish (Spain’s official language) and 

Valenciano. But as the first touristic destination, English is spoken in almost all cafeterias, bars, 

etc. Feel free to ask to the service. 

Travelling info 

Standard electrical voltage is 220-240V AC, 50 Hz, with electrical plug type C (standard in all 

Europe, except UK). Check for a transformer and voltage adapter if necessary with regard 

to your country. Adapters are available in most hardware stores (like El Corte Inglés). 

Banks are open from Monday to Friday between 8:30 to 14:30, some are open on Saturday 

morning but exceptionally from October to April. Automatic tellers are 24-h open and 

mainly housed at the bank entry. Most hotels, restaurants and shops accept the main credit 

cards (American Express, VISA, Mastercard, 4B, Access and Diners Club). But if you want to 

exchange your currencies, you will find exchange offices at the airports, in some hotels and 

in all banks. 

Shops are mainly open from 09:00 to 21:00, some are open till 22h, and in some periods till 

midnight. 

Bar and Restaurants are mainly open during all day, but in some cases a continental timetable 

applies. Generally they serve breakfast between 07:30 to 10:00, lunch between 13:00 to 15:00 

and dinner from 20:30 to 22:30. Hotels have usually wider services, so ask in your hotel. 

Interest phone numbers 

• Emergency services, 112 

• Local Police, 092 

Registration and Technical Secretariat 

The ISC resitration counters will be located in the Valencia Conference Center lobby. Check 

operational hours in the corresponding panel. 

The technical secretariat corresponds to: 

Viajes El Corte Inglés SA. 

División de Congresos, Convenciones e Incentivos 

Gran Vía Fernado el Católico, 3, bajo. 

46008 Valencia 

Phone: +34 963 107 189 

Fax: +34 963 411 046 

Contact: Erika Hvidkjaer Sanjuan 

Email: citruscongress2012@viajeseci.es 

Exhibits – Trade Show 

The exhibition area is located in the main lobby of the Valencia Conference Center (see 

map). 

Delegates are encouraged to visit them. Opening hours are the same as for the ICC 2012. 

I/6 - VALENCIA CONFERENCE CENTER, 18th-23rd NOVEMBER 2012

Poster presentations 

All posters are required to be mounted on Sunday, November 18 from 16:00 to 19:00, and will 

last till November 23. Poster boards are numbered consecutively and accordling to session 

number. The poster identification number can be found on the abstract book and in the list 

provided in the web site, and should be included in the right upper corner of your poster 

to allow match with poster board. The poster presenter should mount their posters on the 

corresponding poster board unless authors’ decision on use the Poster printing service. 

The poster presenter (underlined) is requested to be stationed by their poster during the first 

hour of the assigned session to facilitate discussion. 

All postes are to be removed between 18:00-19:00 on Friday, November 23. Remaining 

posters after this time will be removed by the organization without possibility of recovery. 

Speakers, audio visual and Sci-Technical desk 

Authors are kindly requested to bring their PowerPoint presentations on a USB to upload the 

presentation to the established PC-network at least 24h in advance. No personal computers 

will be allowed in the auditoriums for the presentation to keep the session schedule. 

Slide preview computers will be available to check the presentation with the software to be 

used in the Valencia Conference Center. 

Session conveners will be able to check out a laser pointer for the speakers, and to make 

an advertisement two minutes before the end of allocated presentation time. Presentation 

would be interrupted if time is surpassed to maintain the programme schedule. 

Congress badges 

Congress participants are kindly requested to wear their Congress Badges at all times for 

identification and for security reasons. Congress badge will be required to access to lunch 

hall. 

Congress badge and corresponding tickets will be requested for participation in the Midcongress 

tour and for the congress official dinner. 


SUPPORTERS 

• The 12th ICC has been organized by the International Society of Citriculture 

(ISC), Instituto Valenciano de Investigaciones Agrarias (IVIA) and Fundación 

AGROALIMED. 

• The Organizing Committee would like to give thanks to the following Spanish 

institutions which had provided funds to develop this event. 

• Generalitat Valenciana (GVA), Consejería de Agricultura, Pesca, Alimentación y 

Agua. 

• Generalitat Valenciana (GVA), Consejería de Educación, Formación y Ocupación, 

project number AORG/2012/011. 

• Instituto Nacional de Investigaciones y Tecnología Agraria y Alimentaria (INIA) 

project AC2012-00028-00-00. 


SPONSORS 


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Scientific 

Programme

ICC 2012 PROGRAMME AT GLANCE 


SCIENTIFIC PROGRAMME 

Note: Sessions S04 Citrus biochemistry and S19 Nursery and plant propagation have been removed from 

Programme. 

PLENARY CONFERENCES 

Note: All plenary conferences will take place at Auditorium 1 

• PC01 The Spanish citrus industry 

Luis Navarro 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Spain 

Monday 19 th , 9:30-10:30h 

• PC02 Citrus and health 

Gary Williamson 

School of Food Science and Nutrition, University of Leeds, UK 

Monday 19 th , 11:00-12:00h 

• PC03 The importance of citrus for the juice and beverage industry 

Ademerval Garcia 

Grove 2 Glass Trading GmbH, a ‘The Coca-Cola Company’ subsidiary, Switzerland 

Tuesday 20 th , 9:00-10:00h 

• PC04 Food safety, social compliance and sustainability, in relation to commercial fruit and vegs 

strategies with special reference to citrus 

Gé Happe 

European Sourcing Director Ahold, The Netherlands 

Tuesday 20 th , 15:15-16:15h 

• PC05 The experience of Huanglongbing control in Brazil 

Antonio J. Ayres 

Fundo de Defesa da Citricultura (FUNDECITRUS), Brazil 

Thursday 22 nd , 9:00-10:00h 

• PC06 New genetic and genomic tools for citrus breeding 

Mikeal L. Roose 

University of California, Riverside, USA 

Thursday 22 nd , 10:30-11:30h 

• PC07 Biological control and citrus: a long time fruitful story 

Jacques Brodeur 

Plant Biology Research Institute, Montreal University, Canada 

Friday 23 rd , 9:00-10:00h 

WORKSHOPS 

The purpose of workshops will be to look at recent advances and future prospects on specific 

citrus issues, related to hot topics. The main objective is to bring together members from the Citrus 

community for a thorough and lively discussion on each theme. To promote discussions and active 

interactions, the convener of each workshop will make an introduction on the topic and then open 

and manage the debate. Conveners will make decisions on the best way to organize the debate 

according to the characteristics of each topic. We encourage delegates willing to participate 

in these workshops to get in touch with the conveners, as you will see their e-mails are available. 

Workshops are programmed every day after regular sessions with a format of 2 hours (except W01 

and W03), thus providing enough time for discussion. 


• W01 ‘HLB Control’ 

Convener: J. Bové 

Université de Bordeaux Ségalen - INRA Center, France; joseph.bove@wanadoo.fr 

Thursday 22 nd (17:15-19:15h, at Auditorium 1) and Friday 23 rd (14:15-16:15 h, at Auditorium 2) 

• W02 ‘New mandarin varieties’ 

Convener: P. Aleza 

Instituto Valenciano Investigaciones Agrarias (IVIA), Spain; aleza@ivia.es 

Thursday 22 nd (17:15-19:15h, at Auditorium 2) 

• W03 ‘Procedures for the exploitation of protected and/or patented varieties’ 

Convener: M. Iborra 

Norma Agrícola, Spain; miborra@normagricola.com 

Friday 23 rd (10:30-12:30h, at Room 4) 

• W04 ‘New perspectives in pest control’ 

Convener: A. Urbaneja 

Instituto Valenciano Investigaciones Agrarias (IVIA), Spain; aurbaneja@ivia.es 

Thursday 22nd (17:15-19:15h, at Auditorium 3) 

• W05 ‘Dwarf citrus trees in high-density plantings’ 

Convener: K.D. Bowman 

U.S. Horticultural Research Laboratory, USA; Kim.Bowman@ars.usda.gov 

Tuesday 20 th (18:30-20:30h, at Auditorium 2) 

• W06 ‘Molecular identification of varieties’ 

Convener: T. Shimizu 

National Institute of Fruit Tree Science, Japan; shimizu@affrc.go.jp 

Monday 19 th (17:30-19:30h, at Auditorium 3) 

• W07 ‘Mechanization of citrus harvest’ 

Convener: E. Molto 

Instituto Valenciano Investigaciones Agrarias (IVIA), Spain; molto_enr@gva.es 

Tuesday 20 th (18:30-20:30h, at Room 4) 

• W08 ‘Global citrus industry collaboration on MRL regulatory issues’ 

Convener J.R. Cranney Jr. 

California Citrus Quality Council, USA; jcranney@calcitrusquality.org 

Monday 19 th (17:30-19:30h, at Room 5) 

• W09 ‘Global conservation strategy for citrus genetic resources’ 

Convener: K. E. Hummer 

U. S. Department of Agriculture - Agricultural Research Service National Clonal Germplasm 

Repository, USA; Kim.Hummer@ars.usda.gov 

Monday 19 th (17:30-19:30h, at Room 4) 

• W10 ‘Research activities to support the potential biological effects of citrus fruits in human health’ 

Convener: Francisco A. Tomás-Barberán 

Centro de Edafología y Biología Aplicada del Segura del CSIC (CEBAS-CSIC), Spain; 

fatomas@cebas.csic.es 

Monday 19 th (17:30-19:30h, at Auditorium 2) 

• W11 ‘Quarantine security for tephritid fruit fly pests in citrus’ 

Convener: N.J. Liquido 

USDA-APHIS-PPQ, Center for Plant Health Science and Technology, Plant Epidemiology and Risk 

Analysis Laboratory, USA; Nicanor.J.Liquido@aphis.usda.gov 

Tuesday 20 th (18:30-20:30h, at Room 4) 


SESSION 01: Citrus germplasm and phylogenetics 

Oral presentations at Auditorium 1, on Monday 19 th from 12:00 to 13:30. 

Poster session on Tuesday 20 th 

Conveners: Dr. Gema ANCILLO (Instituto Valenciano Investigaciones Agrarias, Spain) and Dr. Robert 

KRUEGER (U. S. Department of Agriculture - Agricultural Research Service, USA). 

Oral ID Title 

S01O01 

S01O02 

S01O03 

S01O04 

S01O05 

S01O06 

Poster ID Title 

S01P01 

S01P02 

S01P03 

S01P04 

S01P05 

S01P06 

S01P07 

S01P08 

S01P09 

S01P10 

Citron germplasm in Yunnan, China 

Karp D., Krueger R.R., Kahn T., and Hu X. 

Cryopreservation of citrus for long-term conservation 

Volk G.M., Bonnart R., Shepherd A., Krueger R.R., and Lee R.F. 

Genetic diversity and population structure of the mandarin germplasm revealed by 

nuclear and mitochondrial markers analysis. 

Garcia-Lor A., Luro F., Ancillo G., Ollitrault P., and Navarro L. 

Study on genetic diversity of 39 citron germplasm resources with SCoT and ISSR markers 

Zhang S.W., Huang G.X., He X.H., Pan J.C., and Ding F. 

Origin of dwarf, thornless-type trifoliate orange varieties deduced from genome-wide 

genotyping analysis 

Shimizu T., Yoshioka T., Kita M., and Ohta S. 

Multilocus haplotyping by parallel sequencing to decipher the interspecific mosaic 

genome structure of cultivated citrus. 

Curk F., Ancillo G., Garcia-Lor A., Luro F., Navarro L., and Ollitrault P. 

Citrus ichangensis in Sichuan and Chongqing 

Zhang Y., and Zhou X. 

Diverse genetic resources of citrus in North-East region of India 

Huidrom S.D., Singh S. R., and Handique P. J. 

Observations of graft compatibility between Citrus spp and related Aurantioideae 

taxa 

Siebert T., Kahn T., and Krueger R.R. 

Fertility relationships among Citrus and its relatives in the subfamily Aurantioideae 

Siebert T., Ellstrand N., and Kahn T. 

Characterization of seed and embryo abortion during fruit development in several 

citrus cultivars pollinated by Nishiuchi Konatsu (Citrus tamurana) and preliminary trial 

of embryo rescue of aborting embryos 

Honsho C., Tsuruta K., Ryuto K., Sakata A., Kuroki S., Nishiwaki A., and Tetsumura T. 

Diversity analysis of citrus fruit pulp acidity and sweetness: toward to understand the 

genetic control of the fruit quality parameters 

Luro F., Gatto J., Constantino G., and Pailly O. 

Screening a core collection of citrus genetic resources for resistance to Fusarium solani 

Krueger R.R., and Bender G.S. 

Nuclear phylogeny of Citrus and four related genera 

Garcia-Lor A., Curk F., Snoussi H., Morillon R., Ancillo G., Luro F., Navarro L., and Ollitrault P. 

New insights on limes and lemons origin from targeted nuclear gene sequencing and 

cytoplasmic markers genotyping 

Curk F., Garcia-Lor A., Snoussi H., Froelicher Y., Ancillo G., Navarro L., and Ollitrault P. 

Diversity of citron (Citrus medica) and phylogenetic analysis of related citron hybrids 

using molecular markers and essential oil compositions 

Luro F., Venturini N., Costantino G., Tur I., Paolini J., Ollitrault P., and Costa J. 



S01P11 

S01P12 

Analysis of genetic diversity in Tunisian citrus rootstocks 

Snoussi H., Duval M.F., Garcia-Lor A., Perrier X., Jacquemoud-Collet J.C., Navarro L., and 

Ollitrault P. 

Characteristics of Pompia a natural citrus hybrid cultivated in Sardinia 

Mignani I., Mulas M., Mantegazza R., Lovigu N., Spada A., Nicolosi E., and Bassi D. 

SESSION 02: Citrus genetics and breeding 

Oral presentations at Auditorium n. 2, on Thursday 22 nd from 11:30 to 17:00. 


Conveners: Dr. Patrick OLLITRAULT (Centre de Cooperation International en Recherche Agronomique 

pour le Développement - Instituto Valenciano Investigaciones Agrarias, CIRAD-IVIA, Spain) and Dr. 

Jude GROSSER (Citrus Research and Education Center, USA). 

Oral ID Title 

S02O01 

S02O02 

S02O03 

S02O04 

S02O05 

S02O06 

S02O07 

S02O08 

S02O09 

S02O10 

S02O11 

S02O12 

S02O13 

S02O14 

The triploid mandarin breeding program in Spain. 

Navarro L., Aleza P., Cuenca J., Juárez J., Pina J.A., Ortega C., Navarro A., and Ortega V. 

Triploid seedless mandarin breeding in France 

Froelicher Y., Bouffin J., Dambier D., and Ollitrault P. 

Mechanism of 2n gametes formation and centromere mapping in citrus 

Aleza P., Cuenca J., Juárez J., Navarro L., and Ollitrault P. 

Experiences in the development, release and commercialization of new irradiated 

citrus varieties from the citrus breeding program at the University of California Riverside 

Williams T.E. 

Citrus breeding program in Chile 

Martiz J., and Montañola M.J. 

Citrus breeding in South Africa: the latest developments in the programme run by the 

ARC-institute for tropical and subtropical crops 

Sippel A.D., Bijzet Z., Froneman I.J., Combrink N.K., Maritz J.G.J., Hannweg K.F., Severn-Ellis 

A.A., and Manicom B.Q. 

Highlights of the University of Florida, Citrus Research and Education Center’s 

comprehensive citrus breeding and genetics program. 

Grosser J.W., Gmitter Jr. F.G., Ling P., and Castle W.S. 

Advance in S allele determination, S allele frequencies and S-genotyping in citrus. 

Wakana A., Handayani E., Kim J.H., Miyazaki R., Mori T., Sato M., and Sakai K. 

Integrated profiling of furanocoumarins (FCs) in grapefruit and derived hybrids toward 

selection of low FCs varieties. 

Chen C., Gmitter Jr. F.G., Cancalon P., and Greenblatt D.J. 

Breeding new grapefruit-like varieties with low furanocoumarin contents. 

Weissberg M., Yaniv Y., Sobolev I., Fidle L., and Carmi N. 

Genotypic variation of rind colour in citrus tangor ‘Kiyomi’ progenies. 

Combrink N.K., Bijzet Z., Sippel A.D., Booyse M., and Labuschagne M.T. 

Rootstock effects on mandarin fruit traits under control and salinity conditions 

Raga V., Bernet G.P., Carbonell E.A., and Asíns M.J. 

Extension of a citrus genetic linkage map for QTL mapping of freeze tolerance 

Hong Q.-B., Ma X.J., Gong G.-Z., and Peng Z.C. 

Location of a chromosome region linked to Alternaria Brown Spot resistance from the 

evaluation of triploid mandarin populations 

Cuenca J., Aleza P., Iborra E., Vicent A., Ollitrault P., and Navarro L. 



S02P01 

S02P02 

S02P03 

S02P04 

S02P05 

S02P06 

S02P07 

S02P08 

S02P09 

S02P10 

S02P11 

S02P12 

S02P13 

S02P14 

S02P15 

S02P16 

S02P17 

S02P18 

Investigating the parentage of ‘Orri’ and ‘Fortune’ mandarin hybrids 

Barry G.H., Gmitter Jr. F.G., Chunxian C., Roose M.L., and McCollum G. 

Simple PCR-based tolls provide molecular identification of the main rootstock used in 

Sao Paulo State, Brazil 

Coletta-Filho H.D., Pompeu-Jr J., Francisco C.S., and Machado M.A. 

Assignment of SNP allelic configuration in polyploids using Competitive Allele-Specific 

PCR: application to triploid citrus progenies 

Cuenca J., Aleza P., Navarro L., and Ollitrault P. 

The parentage analysis contributes to the validation of high throughput SNP genotype 

calls of citrus 

Fujii H., Nonaka K., Kita M., Shimada T., Endo T., Kuniga T., Ikoma Y., and Omura M. 

Comparative values of SSRs, SNPs and InDels for citrus genetic diversity analysis 

Ollitrault P., Garcia-Lor A., Terol J., Curk F., Ollitrault F., Talon M., and Navarro L. 

Preliminary research on genes and proteins related to a spontaneous mutant of Citrus 

reticulata 

Zeng J.W., Yi G.J., Jiang B., Zhong Y., and Zhong G.Y. 

Allelic diversity of Ferritin II and PMT IV genes related to iron chlorosis in some citrus 

rootstocks 

Aka Kacar Y., Simsek O., Donmez D., Boncuk M., Yesiloglu T., and Ollitrault P. 

Genetic mapping of QTLs associated with drought tolerance in citrus 

Dutra-Souza J., Cristofani-Yaly M., Machado M.A., and Oliveira A.C. 

Evaluation of resistance of ‘Pera’ (Citrus sinensis) genotypes to Citrus Canker in field 

and green-house conditions 

Goncalves-Zuliani A., Nunes W.M.C., Zanutto C., Croce Filho J., and Nocchi P.T.M. 

Susceptibility of mandarins and tangors to Citrus Leprosis under greenhouse conditions 

Nunes M.A., Pereira J.A., Freitas-Astua J., Novelli V.M., and Bastianel M. 

Development of CTV resistant citrus rootstocks using hybridization 

Pinar H., Seday U., Unlu M., and Uzun A. 

Lime Bush (Citrus glauca) hybrids resistant to CTV 

Smith M.W., Gultzow D.L., Newman T.K., and Parfitt S.C. 

Determination of self-incompatibility status of some clementine (Citrus clementina) 

genotypes by histological analysis 

Aka Kacar Y., Aslan F., Eti S., Boncuk M., Simsek O., Yildirim B., Yalcin Mendi Y., Yesiloglu T., 

Distefano G., and La Malfa S. 

Genotyping for male sterility (MS) and MS gene mapping with RAPD markers in citrus, 

especially with precocious flowering seedlings from a cross of HY16 x grapefruit 

Dewi P.S., Wakana A., Tanimoto Y., Fujiwara Y., and Sakai K. 

Embryological studies on ‘URS Campestre’, a new seedless orange cultivar 

Guerra D., Santos R. P. dos, Montero C. R. S, Schwarz S. F.,and Bender R. J. 

Mechanism of seedlessness in a new lemon cultivar Xiangshui [Citrus limon] 

Zhang S.-W., Huang G.H., Ding F., He X.-H., and Pan J.C. 

Differences in the genetic structure of citrus triploid hybrids recovered from 2x X 2x and 

4x X 2x sexual hybridisations 

Aleza P., Cuenca J., Juárez J., Ollitrault P., and Navarro L. 

Efficient haploid production on ‘Wilking’ mandarin by induced gynogenesis 

Jedidi E., Kamiri M., Poullet T., Ollitrault P., and Froelicher Y. 



S02P19 

S02P20 

S02P21 

S02P22 

S02P23 

S02P24 

S02P25 

S02P26 

S02P27 

S02P28 

S02P29 

S02P30 

S02P31 

S02P32 

S02P33 

S02P34 

S02P35 

S02P36 

Differences in ploidy levels of interploidal crosses progenies between diploids and 

tetraploid somatic hybrids in citrus 

Kamiri M., Srairi I., Poullet T., Ollitrault P., and Froelicher Y. 

Gametic configuration and inheritance of SSR markers in tetraploid interspecific and 

intergeneric citrus somatic hybrids 

Kamiri M., Stift M., Srairi I., Chahidi B., Poullet T., Costantino G., Dambier D., Ollitrault P., and 

Froelicher Y. 

Haploid and polyploid hybrids obtained from cross of diploid citrus 

Liu J.J., Chen K.L., He J., and Guan B. 

Chromosome redundancy and phenotypic variation in autotetraploid trifoliate orange 

seedlings 

Oh E.U., Chae C.W., Kim S.B., Park J.H., Yun S.H., Koh S.W., and Song K.W. 

New cybrids resulting from asexual pathway: a promise of the cybridization for creating 

new rootstocks and varieties. 

Dambier D., Petit F., Barantin P., and Ollitrault P. 

Several seedless citrus hybrids selected from tangor x ‘Ponkan’ cross 


New citrus hybrids: selection and genetic studies 

Novelli V.M., Bastianel M., Fernandes K.A., Misságlia J., Latado R.R., Cristofani-Yaly M., 

and Machado M.A. 

Characterization of fruits of hybrids between ‘Sunki’ mandarin [Citrus sunki] and sour 

orange (Citrus aurantium) 

Schinor E.H., Michielin T.H.V., Simonetti L.M., Cristofani-Yaly M., Pompeu Jr. J., and Bastianel M. 

Evaluation of clementine x ‘Kara’ mandarin hybrids 

Seday U., Kafa G., Uysal O., Polatoz S., Uzun A., and Gulsen O. 

Distribution of leaf features in citrus hybrids obtained from clementine 

Uysal O., Kafa G., Seday U., and Polatöz S. 

Optimal dose of gamma irradiation for mutation induction in mandarins 

Handaji N., Benyahia H., Arsalane N., Mouhib M., Ibriz M., Srairi I., Chahidi B., and 

Bourachde Y. 

Effect of budwood irradiation on seed number of clementine, ‘Nova’ and ‘Robinson’ 

mandarins 

Kafa G., Seday U., Uysal O., and Polatöz S. 

Three variegated clementines 


New low seeded mandarin (Citrus reticulata) and lemon (Citrus lemon) selections 

obtained by gamma irradiation in Chile 

Montañola M.J., and Martiz J. 

Radiosensitivity of seeds and nodal segments of citrus rootstocks irradiated in vitro with 

γ-rays from 60Co Tallón C.I., Porras I., Perez-Tornero O. 

Studies on mutation breeding for seedless and low-seeded cultivars of citrus 

Tang X.L., and Ma P.Q. 

Agronomic performance of twenty six clones of ‘Pera’ sweet orange in São Paulo state, 

Brazil 

Carvalho S.A., Latado R.R., Silva L.F.C., and Müller G.W. 

Distribution of fruit characteristics in the group of citrus Setoka nucellar seedlings 

Park J.H., Yun S.H., Koh S.W., and Chae C.W. 



S02P37 

S02P38 

S02P39 

S02P40 

‘Qing-ougan’: The green-peel mandarin mutation of ‘Ougan’ in Zhejiang province, 

China 

Xu J.G., Ke F.Z., and Huang J.Z. 

Hybridization-based citrus breeding program in Turkey 

Uzun A., Gulsen O., Seday S., and Kafa G. 

‘BATEM Fatihi’: A new orange selection from cv. ‘Washington navel’ 

Eryılmaz Z., Dal B., Tuncay M., Balkılıç R., and Gübbük H. 

A new orange cultivar ‘BATEM Baharı’ selected from cv. ‘Valencia Late’ 

Eryılmaz Z., Ercişli S., Gübbük H., and Tuncay M. 

SESSION 03: Citrus genomics 

Oral presentations at Auditorium 2, on Friday 23 rd from 10:30 to 13:00. 


Conveners: Dr. Manuel TALÓN (Instituto Valenciano Investigaciones Agrarias, Spain) and Dr. Fred 

GMITTER Jr. (Citrus Research and Education Center, USA). 

Oral ID Title 

S03O01 

S03O02 

S03O03 

S03O04 

S03O05 

S03O06 

S03O07 

S03O08 

Genome sequence analysis and comparisons reveal ancestral hybridization and 

admixture events in the origins of some citrus cultivars 

Gmitter Jr. F.G., Ollitrault P., Machado M.A., Reforgiato-Recupero G., Talón M., Roose M.L., 

Navarro L., Wu G., Jaillon O., Morgante M., and Rokhsar D.S. 

Sequencing of 150 citrus varieties: linking genotypes to phenotypes 

Terol J., Carbonell J., Alonso R., Tadeo F.R., Herrero A., Ibáñez V., Muñoz J.V., López-García 

A., Hueso L., Colmenero-Flores J.M., Conesa A., Dopazo J., and Talón M. 

Whole genome sequencing and mapping analysis for identifying polymorphism 

among 11 citrus varieties 

Shimizu T., Yoshioka T., Nagasaki H., Kaminuma E., Toyoda A., Fujiyama A., and Nakamura 

Y. 

Sweet orange genome: sequencing, annotation and beyond 

Xu Q., Ruan X., Chen L.L., Chen D.J., Zhu A.D., Chen C.L., Ruan Y., and Deng X.X. 

A reference genetic map of Citrus clementina; citrus evolution inferences from 

comparative mapping 

Ollitrault P., Terol J., Chen C., Federici C.T., Lotfy S., Hippolyte I., Ollitrault F., Bérard A., 

Chauveau A., Cuenca J., Costantino G., Kacar Y., Mu L., García-Lor A., Froelicher Y., 

Aleza P., Boland A., Billot C., Navarro L., Luro F., Roose M.L., Gmitter Jr. F.G., Talón M., and 

Brunel D. 

The chromosomes of citrus: from a unifying nomenclature to the evolution of karyotypes 

Silva S.C., Mendes S., Moraes A.P., Marques A., Mirkov T.E., Iglesias D.J., Ibáñez V., Tálon M., 

Soares Filho W.S., Guerra M., and Pedrosa-Harand A. 

Analysis of the clementine floral transcriptome uncovers candidate genes involved in 

self-incompatibility 

Caruso M., Lo Cicero L., Distefano G., Merelo P., La Malfa S., Tadeo F.R., Talón M., Lo Piero 

A.R., and Gentile A. 

Citrus gene function analysis using a viral vector based on the Citrus leaf blotch virus 

genome 

Agüero J., Velázquez K., Vives M.C., Pina J.A., Navarro L., Moreno P., and Guerri J. 



S03P01 

S03P02 

S03P03 

S03P04 

S03P05 

S03P06 

S03P07 

S03P08 

S03P09 

S03P10 

S03P11 

S03P12 

S03P13 

S03P14 

S03P15 

Expression analysis of genes differentially expressed in stem tissue of two lemon cultivars 

Koutsioumari E.M., and Voloudakis A.E. 

Transcriptome profile analysis of Citrus Canker resistance of Chinese citron (Citrus 

medica) via massively parallel mRNA sequencing 

Li D.Z., Dai S.M., Li N., and Deng Z.N. 

Characterization of genes associated with two agronomically important traits in citrus: 

drought tolerance and fruit color 

Costa M.G.C., Cidade L.C., de Oliveira T.M., Martins C.P.S., Mendes A.F.S., Pereira S.L.S., 

Pedrosa A.M., Gesteira A.S., Girardi E.A., Coelho-Filho M.A., Soares Filho W.S., and 

Machado M.A. 

Expression of Ptcor8 gene induced by low temperature as related to cold resistance 

in citrus 

Long G.Y., Song J.Y., Luo K., Deng Z.N., Li N., and Gentile A. 

Cloning and characterization of a prolin-rich protein gene CsPRP4 from citrus 

Ma Y.Y., Zhang L.Y., Zhu S.P., and Zhong G.Y. 

Ploidy and gene expression in clementine 

Niñoles R., Aleza P., Castillo M.C., Navarro L., and Ancillo G. 

Expression of flowering genes in different shoot types in citrus 

Muñoz-Fambuena N., Mesejo C., González-Mas M.C., Iglesias D.J., Primo-Millo E., and 

Agustí M. 

Shortening the juvenile phase in Arabidopsis plants by ectopic expression of citrus 

transcription factors 

Castillo M. C., Navarro L., and Ancillo G. 

Differential expression of proteins related to primary metabolism in ‘Moncada’ mandarin 

leaves with contrasting fruit load 

Muñoz-Fambuena N., Mesejo C., Agustí M., Tárraga S., Iglesias D.J., Primo-Millo E., and 

González-Mas M.C. 

Proteins related to stress and redox state of ‘Moncada’ mandarin leaves with contrasting 

fruit load 

Muñoz-Fambuena N., Mesejo C., Agustí M., Tárraga S., Iglesias D.J., Primo-Millo E., and 

González-Mas M.C. 

Genomic compositions and origins of Citrus sinensis, Citrus clementina and Citrus 

poonensis as revealed by genome-wide analysis of citrus ESTs 

Zhong G.Y., Wu B., Zeng J.W., Jiang B., and Yang R.T. 

Genomic sequencing and comparative analysis of Citrus platymamma (Byungkyool) 

by using next-generation sequencing technology 

Chung S.J., Han S.I., Jin S.B., Kim Y.W., Yun S.H., Riu K.Z., and Kim J.H. 

Fast and cost-effective DNA marker typing method with accuracy for citrus by direct 

PCR and multiplexed post-labeling 

Ohta S., Yano K., Kurita Y., Kita M., Yoshioka T., Nesumi H., and Shimizu T. 

Data mining and systems biology for identifying key genes involved in citrus quality 

Silva E.M.A, Bernardes L.A.S., Ollitrault P., Bonatto D., and Micheli F. 

Genotyping and mutation scanning by high resolution melting (HRM) analysis of citrus 

EST-SNPs and SSRs 

Distefano G., La Malfa S., Caruso M., Lo Piero A.R., Nicolosi E., and Shu-Biao W. 


SESSION 05: BIOTECHNOLOGY 

Oral presentations at Auditorium 1, on Tuesday 20 th from 10:30 to 13:00. 

Poster session on Monday 19 th 

Conveners: Dr. Leandro PEÑA (Instituto Valenciano Investigaciones Agrarias, Spain) and Dr. Xiuxin 

DENG (Huazhong Agricultural University, China). 

Oral ID Title 

S05O01 

S05O02 

S05O03 

S05O04 

S05O05 

S05O06 

S05O07 

S05O08 

S05O09 

S05O10 

S05O11 


S05P01 

S05P02 

S05P03 

Unlocking the molecular secret of blood orange 

Butelli E., Licciardello C., Reforgiato-Recupero G., and Martin C. 

A novel carotenoid cleavage activity responsible for the biosynthesis of citrus fruitspecific 

apocarotenoids 

Rodrigo M.J., Alquézar B., Carmona L., Alós E., Al-Babili S., and Zacarías L. 

Biosynthesis and regulation of carotenoids in citrus callus 

Xu J., Gao H.J., Deng X.X., and Zhang H.Y. 

Terpene downregulation triggers innate immunity and resistance to fungal pathogens 

in orange fruits 

Rodríguez A., Shimada T., Cervera M., Alquézar B., Gadea J., Gómez-Cadenas A., De 

Ollas C., Rodrigo M.J., Zacarías L., and Peña L. 

Improving in vivo antioxidant properties of orange fruits through increased β-carotene 

content 

Pons E., Alquézar B., Rodríguez A., Martorell P., Genovés S., Llopis S., González N., Ramón 

D., Rodrigo M.J., Zacarías L., and Peña L. 

RNA interference against the three Citrus tristeza virus genes encoding silencing 

suppressors confers complete resistance to the virus in transgenic ‘Mexican’ lime plants 

Soler N., Plomer M., Fagoaga C., Moreno P., Navarro L., Flores R., and Peña L. 

Further verification of the resistance of ‘C-05’ citron to Citrus Canker disease 

Liu L.P., Li D.Z., Li J.H., Li N., and Deng Z.N. 

Genetic transformation of citrus species aiming to increase tolerance to drought stress 

Carlos E.F., Ariyoshi C., Felício M.S., Shimizu P., Souza G.V., Kudo S.A., Silva L.M., Silva A.J.M., 

Cação S.M.B., and Vieira L.G.E. 

Targeted cybridization in citrus and transcript profiling of a male sterile cybrid pummelo 

containing cytoplasm from satsuma mandarin 

Guo W.W., Zheng B.B., Xiao S.X., Grosser J.W., and Deng X.X. 

In vitro anther culture of several cultivars of Citrus sinensis and Citrus clementina. 

Cardoso J.C., Abdelgallel A., Chiancone B., Rocha Latado R., Lain O., Testolin R., and 

Germanà M.A. 

Bioethanol production from mandarin (Citrus unshiu) peel waste 

Choi I.S., Wi S.G., and Bae H.J. 

Screening and analyzing the root-specific genes of Poncirus trifoliata 

Yao L.X., Chen S.C., He Y.R., Lei T.G., Xu L.Z., Liu X.F., and Peng A.H. 

Comprehending crystalline β-carotene accumulation by comparing engineered cell 

models and natural carotenoid-rich system of citrus 

Cao H.B. , Zhang J.C., Xu J.D., Ye J.L., Yun Z., Xu Q., Xu J., and Deng X.X. 

Analyses of expressed sequence tags (ESTs) of ‘Barnfield’ navel orange via constructing 

of a subtractive cDNA library between oleocellosis and healthy rind 

Wei Z.X., Hong L., Cheng C.F., Wu C.Q., and Qi J.R. 



S05P04 

S05P05 

S05P06 

S05P07 

S05P08 

S05P09 

S05P10 

S05P11 

S05P12 

S05P13 

S05P14 

S05P15 

S05P16 

S05P17 

S05P18 

Control of flowering time in citrus through ectopic overexpression of flowering locus T 

(FT) and apetala1 (AP1) from sweet orange 

Rodríguez A., Cervera M., and Peña L. 

Overexpression of a chromoplast-specific lycopene β-cyclase (β-LCY2) gene in orange 

fruit 

Alquézar B., Pons E., Rodríguez A., Rodrigo M.J., Zacarías L., and Peña L. 

Genetic transformation of Citrus sinensis with attacin A gene driven by phloem tissue 

specific promoters for resistance to Candidatus Liberibacter spp. 

Tavano E.C.R., Harakava R., Vieira M.L.C., Mourão Filho F.A.A., and Mendes B.M.J. 

D-limonene downregulation in transgenic sweet orange provides protection against 

Citrus Black Spot symptoms induced in detached fruits 

Kava-Cordeiro V., Rodríguez A., Vicent A., Glienke C., and Peña L. 

Resistance to Citrus tristeza virus in Citrus sinensis transgenic plants 

Muniz F.R., Harakava R., Rezende J.A.M., Moore G.A., Febres V.J., Mourao Filho F.A.A., 

and Mendes B.M.J. 

Production of a recombinant miraculin protein in transgenic citrus cell suspension 

cultures 

Jin S.B., Sun H.J., Kim Y.W., Bachchu M.A.A., Yun S.H., Riu K.Z., and Kim J.H. 

Transgenic sweet orange rootstocks overexpressing a osmotin like PR-5 protein show 

resistance against Phytophthora Foot Rot in the field 

Peris J.E., Vicent A., and Peña L. 

Evaluation of transgenic oranges expressing the stx ia gene for resistance to Citrus 

Canker 

Marques V.V., Miller A.M., Bagio T.Z., Souza G.V., Meneguin L., Vieira L.G.E., Pereira L.F.P., 

and Leite J.R.R.P. 

Transgenic ‘Mexican’ lime plants expressing the gene p23 from Citrus tristeza virus (CTV) 

under the control of a phloem-specific promoter display symptoms closely similar to 

those accompanying virus infection 

Soler N., Fagoaga C., López C., Moreno P., Navarro L., Flores R., and Peña L. 

Efficient deletion of the selectable marker gene from transgenic citrus via the Cre/loxp 

system 

Zou X.P., Peng A.H., Liu X.F., He Y.R., Xu L.Z., and Chen S.C. 

Assessment of pollen-mediated transgene flow in citrus under experimental field 

conditions 

Pons E., Navarro A., Ollitrault P., and Peña L. 

Functional analysis of a citrus transcription factor with mature fruit-specific expression 

using transgenic tomato 

Endo T., Shimada T., Fujii H., Sugiyama A., Nakano M., Ikoma Y., and Omura M. 

Effect of the citrus lycopene β-cyclase transgene on carotenoid metabolism in 

transgenic tomato fruits 

Guo F., Zhou W.J., Zhang J.C., Xu Q., and Deng X.X. 

Role of the sweet orange tau glutathione transferases (csgstu) in transgenic tobacco 

plant detoxification from xenobiotics 

Lo Cicero L., Madesis P., Tsaftaris A., and Lo Piero A.R. 

An alternative transformation method in citrus using cell-penetrating peptides (CPPs) 

Jensen S.P., Febres V.J., and Moore G.A. 



S05P19 

S05P20 

S05P21 

S05P22 

S05P23 

S05P24 

S05P25 

S05P26 

S05P27 

S05P28 

S05P29 

S05P30 

S05P31 

S05P32 

S05P33 

Establishment of a transient expression system in citrus via agro-infiltration 

Dai S.M., Li F., Yan J.M., Li D.Z., Li R.H., and Deng Z.N. 

Improvement of transformation efficiency in citrus 

Yang L., Hu W., Xie Y.M. , Li Y., and Deng Z.N. 

Improvement of genetic transformation with mature explants of sweet orange (Citrus 

sinensis) 

Xie Y.M., Yang L., Hu W., Li Y., and Deng Z.N. 

Efficient propagation and rooting of citrus rootstocks adult explants using different 

basal medium and plant growth regulators 

Tallón C.I., Porras I., and Pérez-Tornero O. 

Optimization of in vitro organogenesis and plantlet regeneration of sweet orange from 

mature tissue 

Castro L.M., Mendes B.M.J., and Mourão Filho F.A.A. 

Applications of citrus shoot-tip grafting in vitro 

Juárez J., Aleza P., and Navarro L. 

Microshoot tip grafting in vitro-a technique for establishment of disease free scion bank 

of Citrus reticulata var. Khasi mandarin 

Sanabam R.S., Huidrom S.D., and Handique P.J. 

Elimination of Spiroplasma citri by somatic embryogenesis from citrus stigma and style 

culture: preliminary results 

Frasheri D., Moujahed R., Djelouah K., Carra A., Carimi F., Valentini F., and D’Onghia A.M. 

The study on callus induction of citrus anther culture in vitro 

Luo J.Q., Xu J.G., Wang P., Ke F.Z., and Nie Z.P. 

Induction of tangerine embryogenic calli from unfertilized or immature ovules 

Machado M.P., de Bona C.M., and Biasi L.A. 

Chromosome instability in ‘Carrizo’ citrange x Citrus macrophylla somatic hybrids 

Pensabene G., Ruíz M., Aleza P., Olivares-Fuster O., Ollitrault P., and Navarro L. 

Preliminary results on biotization of encapsulated in vitro-derived propagules of ‘Carrizo’ 

citrange (Citrus sinensis × Poncirus trifoliata) 

Germanà M.A., Micheli M., Chiancone B., Bianco C., Casales F., and Defez R. 

Biodegradable films made from PLA-limonene blends for food active packaging 

applications 

Arrieta M.P., López J., Ferrándiz S., and Peltzer M. 

PLA and PLA-PHB incorporated with limonene for biodegradable food packaging 

Arrieta M.P., López J., Ferrándiz S., and Peltzer M. 

Shoot tip grafting (STG) in commercial production of disease free, quality-bud grafts of 

citrus in Central India: the present status 

Vijayakumari N. 


SESSION 06: Fruit physiology 

Oral presentations at Auditorium 2, Monday 19 th from 12:00 to 13:30. 


Conveners: Dr. Manuel AGUSTÍ (Instituto Agroforestal del Mediterráneo – Universidad Politécnica de 

Valencia, Spain) and Dr. Alfredo P. GRAVINA (Universidad de la Republica, Uruguay) 

Oral ID Title 

S06O01 

S06O02 

S06O03 

S06O04 

S06O05 

S06O06 


S06P01 

S06P02 

S06P03 

S06P04 

S06P05 

S06P06 

S06P07 

Effect of male-female interaction and temperature variation in citrus pollen performance 

Distefano G., Hedhly A., Las Casas G., La Malfa S., Cicala A., La Rosa G., Herrero M., and 

Gentile A. 

Abscission of reproductive structures in citrus and its control with brassinosteroids and 

girdling 

Pérez M.C., Almenares G., Torres W., Aranguren M., Betancourt M., García M.E., Núñez 

M., Llauger R.E., Mahouachi J., Iglesias D.J., and Talón M. 

“To fall or not to fall, that’s the question!” Molecular mechanisms underlying organ 

abscission in citrus 

Tadeo F. R., Agustí J., Merelo P., Estornell L.H., Cercós M., Terol J., Domingo C., and Talón, M. 

Carbohydrate control over carotenoid build-up in citrus is conditional on fruit ontogeny 

Fanciullino A.L., Poiroux-Gonord F., Poggi I., and Urban L. 

Largely altered terpenoids production in red-fleshed fruits of ‘Cara Cara’ navel orange 

(Citrus sinensis) in comparison with pale-fleshed Seike navel orange 

Xu J., He M., Liu X., Gao H.J., Wang Z., Deng X.X., Cheng Y.J., and Zhang H.Y. 

Endogenous factors affecting fruit color development in navel sweet oranges 

Gambetta G., Gravina A., Fasiolo C., Martínez-Fuentes A., Reig C., Mesejo C., Bentancur 

O., and Agustí M. 

Effect of continuously high temperature throughout a growth period on flowering, 

physiological fruit drop and fruit quality in satsuma mandarin 

Sato K.S., Fukamachi H., and Ikoma Y. 

Evaluations of potential fruit abscission and characteristics of seeded and seedless fruit 

abscission in several citrus species during physiological fruit drop 

Kitajima A., Li X., Habu T., Kataoka K., Nakazaki T., and Yonemori K. 

Cross-pollination and control of seed formation in ‘Afourer’ mandarin 

Gravina A., Gambetta G., Fasiolo C., Espino M., and Rivas F. 

Changes of nutrient element contents and accumulation in fruit of navel orange 

during fruit growth and development 

Peng L.Z., Fa X., Cailun J., Li C., and Lili L. 

The effects of source-sink ratio on leaf photosynthetic characteristics of ‘Newhall’ navel 

orange 

Chun C., Wenwen Z., Liangzhi P., Lili L., Xingzheng F., Li C., Xiaohuan M., Fa X., Cai L., and 

Cailun J. 

Anatomy of abnormal ‘HB’ pummelo caused by boron deficiency 

Li S., Liu Y.Z., Yang C.Q., and Peng S.A. 

Pre-harvest rind breakdown in New Zealand and a comparison with similar problems 

reported from other countries 

Pyle K.R. 



S06P08 

S06P09 

S06P10 

S06P11 

S06P12 

S06P13 

S06P14 

S06P15 

S06P16 

The effect of combined spraying of gibberellin and prohydrojasmon on peel puffing in 

satsuma mandarin 

Ikoma Y., Matsumoto H.M., and Sato K.S. 

Production cost reduction technical development of ‘Shiranuhi’ mandarin hybrid in 

plastic house cultivation used underground air and air mixer 

Han S.H. 

Abscission study during citrus fruit maturation in Corsica: unfavorable environmental 

conditions for fruit shedding 

Khefifi H., Ben Mimoun M., Luro F., and Morillon R. 

Fruit quality characteristics of very early satsuma mandarin by soil mulching with 

polyporous reflective sheet 

Han S.G., Kim Y.H., and Moon Y.E. 

Fruit growth and sugar and acid characteristics in leafy and leafless fruits of satsuma 

mandarin 

Kim S.B., Oh E.U., Yun S.H., Oh H.W., and Song K.J. 

Physiological investigation of June drop in ‘Thomson’ navel orange (Citrus sinensis) in 

north of Iran 

Akhlaghi Amiri N., Asadi Kangarshahi A., and Arzani K. 

Reducing alternate bearing index in satsuma mandarin by nitrogen management and 

pruning in north of Iran 

Asadi Kangarshahi A., Akhlaghi Amiri N., and Savaghebi Gh.R. 

Possibility of adjusting alternate bearing cycle in satsuma mandarin (Citrus unshiu) in 

north of Iran 

Asadi Kangarshahi A., and Akhlaghi Amiri N. 

Reproductive behavior of plants of ‘Valencia’ sweet orange under two soil moisture 

conditions 

Laskowski L.L. 

SESSION 07: Regulation of growth and development 



Conveners: Dr. Domingo IGLESIAS (Instituto Valenciano Investigaciones Agrarias, Spain) and Dr. James 

SYVERTSEN (Citrus Research and Education Center, USA). 

Oral ID Title 

S07O01 

S07O02 

S07O03 

S07O04 

S07O05 

S07O06 

Citrus developmental research: a historic, conceptual perspective 

Goldschmidt E. 

Stock-scion interactions in grafted citrus: a role for microRNA 

Tzarfati R., Ben-Dor S., Sela I., and Goldschmidt E.E. 

Alternate bearing in Citrus reticulata - An overview 

Verreynne J.S., Faber B.A., and Lovatt C.J. 

Relationship between a citrus FLOWERING LOCUS T expression and fruit bearing 

Nishikawa F., Iwasaki M., Fukamachi H., and Endo T. 

Managing drought stress of oranges under Sao Paulo-Mina Gerais, Brazil conditions to 

optimize flower bud induction and productivity 

Albrigo L.G., and Carrera R.R. 

Exploring microRNA-target-modulation in citrus somatic embryogenesis by highthroughput 

small RNA and degradome sequencing 

Wu X.M., Liu M.Y., Xu Q., Deng X.X., and Guo W.W. 



S07P01 

S07P02 

S07P03 

S07P04 

S07P05 

S07P06 

S07P07 

S07P08 

S07P09 

S07P10 

S07P11 

S07P12 

S07P13 

Periods of normal and induced vegetative and reproductive shoots of Persian lime 

(Citrus latifolia) 

Medina-Urrutia V.M., Durán-Martínez C.M., Virgen-Calleros G., Robles-González M.M., 

and Rendon-Salcido L.A. 

Daily temperature amplitude affects the vegetative growth and carbon metabolism 

of orange trees in a rootstock-dependent manner 

Bueno A.C.R., Prudente D.A., Machado E.C., and Ribeiro R.V. 

The effects of paclobutrazol and fruit on flowering and carbohydrate accumulation in 

roots, branches and leaves of alternate bearing clementine mandarin 

Martínez-Fuentes A., Mesejo C., Muñoz-Fambuena N., Reig C., González-Mas M.C., 

Iglesias D.J., Primo-Millo E., and Agustí M. 

Fruit set in orange with phytohormones and its relation to endogeneous levels of GA3 Galván J.J., Martínez A., López N., and Salazar O. 

Analysis of expressed proteins in the pollen tube occurring in the self-incompatible 

response using mass- or single-culture system of mature pollen in citrus 

Abe A., Uchida A., Hoshino Y., Sakakibara Y., Suiko M., and Kunitake H. 

Hormone complex and micronutrients in production and fruit quality of ‘Valencia’ 

sweet orange 

Galván J.J., López N., and Tolentino A. 

Effects of Triclopyr (3,5,6-trichloro-2-pyridyloxyactetic acid) applications on fruit quality 

of ‘SRA63’, ‘SRA85’, ‘SRA88’ and ‘SRA92’ clementine 

Zurru R., Deidda B., Dessena L., and Mulas M. 

Foliar application effect of the 3,5,6-TPA on ‘Tarocco’ red orange yield and fruit size in 

on years of Eastern Sicily orchard 

Tumminelli R., Marano G., Carta Cerella D., and Sinatra V. 

Fruit thinning of ‘Okitsu’ satsuma mandarin 

Rivadeneira M.F., Gómez C., and Silva Muller W. 

Transcript accumulation of flowering genes in response to water deficit and gibberellins 

during floral induction in Citrus sinensis 

Chica E.J., and Albrigo L.G. 

The effect of ethyclozate on tree water stress and fruit quality of satsuma mandarin 

Okuda H.O., Ichinokiyama H.I., and Noda K.N. 

Relationship between flower intensity, oxidative damage and protection in citrus under 

water stress conditions 

Manzi M., Borsani O., Díaz P., and Rivas F. 

The influence of climate on the components of yield and quality for Cuban citrus fruits. 

Adaptation to climate change 

Pérez M.C., Almenares G., Betancourt M., Aranguren M., García M.E., Sistachs V., Núñez 

M., Torres W., Oliva H., Noriega C., and Llauger R.E. 


SESSION 08: Abiotic stress 

Oral presentations at Auditorium 3, on Friday 23 rd from 14:15 to 16:45 


Conveners: Dr. Aurelio GÓMEZ CADENAS (Universitat Jaume I, Spain) and Dr. Ji-Hong LIU (Huazhong 

Agricultural University, China) 

Oral ID Title 

S08O01 

S08O02 

S08O03 

S08O04 

S08O05 

S08O06 

S08O07 

S08O08 


S08P01 

S08P02 

S08P03 

S08P04 

S08P05 

S08P06 

Polyamines function as a key player in stress tolerance: physiology and molecular 

aspects 

Liu J.-H. 

Omics’ and chemical approaches used to monitor iron-deficiency in citrus rootstocks 

Licciardello C., Muccilli V., Torrisi B., Tononi P., Fontanini D., Allegra M., Sciacca F., Foti S., 

Delledonne M., Intrigliolo F., and Reforgiato Recupero G. 

Root protein interatomic network obtained from citrus seedlings subjected to water 

deficit 

Magalhães De Oliveira T., Silva F., Morillon R., Coelho Filho M.A., Neves D.M., Costa 

M.G.C., Pirovani C.P., and Bonatto D. 

Hormone and metabolite traits related to abiotic stress tolerance in citrus 

Arbona V., de Ollas C., Argamasilla R., López-Climent M.F., and Gómez-Cadenas A. 

The adaptation of ‘Sunki Maravilha’ mandarin to drought depends on the ABA 

accumulation balance between roots and canopy 

Neves D.M., Coelho Filho M.A., Bellete B.S., Silva M.F.G.F., Souza D.T., Soares Filho W.S., 

Costa M.G.C. , and Gesteira A.S. 

Roots are necessary for the responses of in vitro-cultured citrus plants to high salinity but 

not to osmotic stress 

Pérez Clemente R.M., Montoliu A., Vives-Peris V., Espinoza V., Zandalinas S.I., and Gómez- 

Cadenas A. 

Physiological analysis of salt stress behaviour of citrus species and genera: low chloride 

accumulation as an indicator of salt tolerance 

Hussain S., Luro F., Costantino G., Ollitrault P., and Morillon R. 

Microsprinkler irrigation for frost protection of citrus in Florida 

Parsons L.R. 

Response of ‘Washington’ navel orange plants to application of Helpstar and Saltrad 

as saline correctors 

El-SHazly S.M., Eisa A.M., and Sarhan Z.H. 

Effects of salinity on some citrus rootstock 

Yeşiloğlu T., İncesu M., Yılmaz B., Tuzcu Ö., Uysal Kamiloğlu M., and Çimen B. 

Salt stress tolerance in acidic and sweet mandarins 

Ben Yahmed J., Ben Mimoun M., Talon M., Ollitrault P., and Morillon R. 

Changes in transcriptional profiles of mature and immature citrus leaves acclimated 

to salinity 

Pérez-Pérez J.G., Talón M., Brumós J., Botía P., and Colmenero J.M. 

Role of ammonium nutrition on salt-induced oxidative stress in ‘Carrizo’ citrange plants 

Fernández-Crespo E., Gómez-Pastor R., Matallana E., Llorens E., Lapeña L., Scalschi L., 

Camañes G., and García-Agustín P. 

Characterization of the Arum-type mycorrhiza in Citrus macrophylla rootstock under 

salinity stress 

Rodríguez Morán M., Navarro J.M., and Morte A. 



S08P07 

S08P08 

S08P09 

S08P10 

S08P11 

S08P12 

S08P13 

S08P14 

S08P15 

S08P16 

S08P17 

S08P18 

S08P19 

S08P20 

S08P21 

S08P22 

S08P23 

S08P24 

S08P25 

In vitro screening of four genotypes of citrus for salt tolerance 

Chetto O., Dambier D., Fadli A., Talha T.A., Benkirane B., and Benyahia B.H . 

Screening of ten citrus rootstocks for salt tolerance at seedling stage 

Fadli A., Chetto O., Talha A., Beniken L., Benkirane R., And Benyahia H. 

Physiological response of Citrus macrophylla inoculated with arbuscular mycorrhizal 

fungi under salt stress 

Navarro J.M., Morte A., Rodríguez Morán M., and Pérez-Tornero O. 

Cloning and functional analysis of stress-responsive genes in Poncirus trifoliata 

Liu J.H., Wang J., Huang X.S., and Sun P.P. 

Characterization of water deficit tolerance of Poncirus trifoliata genotypes as related 

diversity 

Ben Yahmed J., Costantino G., Ben Mimoun M., Talon M., Ollitrault P., Morillon R., and Luro F. 

Screening nine citrumelo rootstocks for tolerance to drought conditions 

Fadli A., Beniken L., Omari F.E., Benkirane R., and Benyahia H. 

The effect of water stress on ABA, JA and physiological characteristic of citrus 

Xie S.X., Lu X.P., Nie Q., and Zhao X.L. 

Physiological responses of diploid and doubled diploid ‘Rangpur’ lime and ‘Carrizo’ 

citrange -under water deficit 

Magalhães de Oliveira T., Micheli F., Maserti E., Navarro L., Talon M., Ollitrault P., Gesteira 

A. S., and Morillon R. 

Flooding and soil temperature affect photosynthesis of citrus rootstock leaves 

Otero A., Goñi Altuna C.T., and Syvertsen J.P. 

Flooding affects fruitlet abscission in satsuma mandarin 

Goñi Altuna C.T., Otero A., and Syvertsen J.P. 

Frost damage in lemon orchards in the region of Murcia 

Conesa A., Martinez-Nicolas J., Manera J., and Porras I. 

Physiological investigation of tolerance to iron chlorosis of ‘Navelina’ orange budded 

on different citrus rootstocks 

Çimen B., Yeşiloğlu T., İncesu M., and Yılmaz B. 

Differential tolerance to iron deficiency of citrus rootstocks grown in calcareous soil 

İncesu M., Yeşiloğlu T., Tuzcu Ö., and Çimen B. 

Orange varieties as interstock in ‘Verna’ lemon trees increase the salt tolerance but not 

the drought or flooding tolerance 

Gimeno V., Simón I., Martínez V., Nieves M., Balal R.M., and Garcia-Sanchez F. 

Environmental effects on citrus growth and yield in the arid and semi-arid conditions of 

kingdom of Saudi Arabia 

Aljaleel A.A. 

Micromorphological studies on the relation between fruit development and creasing 

in orange (Citrus sinensis cv. ‘Moro’ sanguine) 

Rajaei H. 

Behavior of diploid and tetraploid genotypes of ‘Carrizo’ citrange under abiotic stresses 

Ruiz M., Pina J. A., Alcayde E., Morillon R., Navarro L., and Primo-Millo E. 

Comparison of photosynthesis and antioxidant performance of several Citrus and 

Fortunella species under natural chilling stress 

Santini J., Giannettini J., Pailly O., Herbette S., Ollitrault P., Berti L., and Luro F. 

‘Flying Dragon’ as a very cold hardy citrus rootstock in Northern Iran 

Ebrahimi Y., Joshari H., Tavakoli A., Ghasemi S., and Rajabi A. 


SESSION 09: Postharvest physiology and pathology 

Oral presentations at Auditorium 3, on Thursday 22 nd from 11:30 to 17:00. 


Conveners: Dr. Lorenzo ZACARIAS (Instituto de Agroquímica y Tecnología de Alimentos del CSIC, 

Spain), Dr. Jacqueline J. BURNS (Citrus Research and Education Center, USA) and Dr. M.T. LAFUENTE 

(Instituto de Agroquímica y Tecnología de Alimentos del CSIC, Spain) 

Oral ID Title 

S09O01 Genome sequence of the necrotrophic fungus Penicillium digitatum, the main 

postharvest pathogen of citrus 

Ballester A.R., Marcet-Houben M., de la Fuente B., Harries E., Marcos J.F., Gabaldón T., 

and González-Candelas L. 

S09O02 RNA-Seq analysis of yeast antagonist Metschnikowia fructicola during interactions with 

Penicillium digitatum and grapefruit peel reveals specific transcriptional responses 

Hershkovitz V., Sela N., Taha L., Rafael G., BenDayan C., Feygenberg O., Aly R., Wisniewski 

M., and Droby S. 

S09O03 The mitogen-activated protein kinase PdSLT2 of Penicillium digitatum is required for 

fungal pathogenesis/virulence during citrus infection 

De Ramón-Carbonell M., and Sánchez-Torres P. 

S09O04 Function of PdCrz1, a calcineurin-responsive transcription factor, in Penicillium digitatum 

in conidiation, virulence and responses to abiotic stresses 

Zhang T., and Li H. 

S09O05 The protein O-Mannosyltransferase PMT2 of the citrus-specific postharvest pathogen 

Penicillium digitatum is involved in conidiogenesis, virulence and sensitivity to the 

antifungal peptide PAF26 

Harries E., Gandía M., Carmona L., and Marcos J.F. 

S09O06 PdCYP51B, a new sterol 14α-demethylase gene of Penicillium digitatum involved in 

resistance to imazalil and other fungicides inhibiting ergosterol synthesis 

Sun X.P., Wang J.Y., Feng D., and Li H.Y. 

S09O07 Current and emerging strategies for Sour Rot management of citrus in Australia 

Taverner P.D., and Cunningham N.M. 

S09O08 A new perspective in controlling postharvest citrus rots 

Fallanaj F., Sanzani S.M., and Ippolito A. 

S09O09 Global solution for preserving citrus fruit using natural treatments 

Conesa E. 

S09O10 Could ethylene influence Peteca Spot incidence of lemon fruit? 

Cronjé P.J.R. 

S09O11 ´Tahiti´ lime post-harvest evaluation and non-destructive assessment of essential oils by 

NIR spectroscopy 

Diaz-Candelas C.C., Morales-Payán J.P., and Romañach R. 

S09O12 Postharvest blue light treatments affect citrus fruit susceptibility to disease by altering 

oxylipin biosynthesis 

Alferez F., Liao H.-L., and Burns J.K. 

S09O13 Potassium sorbate increases citrus weight loss in postharvest treatments but it does not 

provide good decay control in wax 

Parra J.P. 


S09P01 

Transcriptional regulation of the Citrus sinensis ABA-signalosome during fruit dehydration 

Romero P., Rodrigo M.J., and Lafuente M.T. 



S09P02 

S09P03 

S09P04 

S09P05 

S09P06 

S09P07 

S09P08 

S09P09 

S09P10 

S09P11 

S09P12 

S09P13 

S09P14 

S09P15 

S09P16 

S09P17 

S09P18 

S09P19 

Delayed color break in ‘Tardivo’, a late ripening mandarin mutant, is related to a 

defective ethylene response 

Alos E., Distefano G., Rodrigo M.J., Gentile A., and Zacarias L. 

Comparative proteome and metabolome profiling analysis heat treatment induced 

fruit resistibility during postharvest storage 

Yun Z., Liu P., Liu S.Z., Luo T., Jin S., Gao H.J., Xu Q., Xu J., Cheng Y.J., and Deng X.X. 

Postharvest water stress leading to peel disorders in citrus fruit involves regulation of 

phospholipases by ABA 

Romero P., Gandia M., and Alférez F. 

Quality attributes of ‘Valencia’ orange (Citrus sinensis) fruit coated with different edible 

covers 

Mohammadi Shamloo M., Sharifani M. M., Daraei Garmakhany A., and Seifi E. 

Influence of maturity stage and intermittent warming on storage of ‘Nagpur’ mandarin 

fruit 

Ladaniya M. 

Effect of postharvest temperature on accumulation of primary metabolites in juice 

sacs of satsuma mandarin (Citrus unshiu) fruit 

Matsumoto H.M., and Ikoma Y. 

Stem End Rind Breakdown of citrus fruit a new postharvest physiological disorder of 

lemon fruit in Tucuman (Argentina) 

Torres Leal G.J., Velazquez P.D., Carbajo M.S., Farias M.F., and Pedraza J.R. 

The effects of some postharvest applications on fruit quality of ‘Valencia-Late’ oranges 

Dal B. 

Influence of light on carotenoid accumulation in ‘Star Ruby’ grapefruit 

Lado Lindner J., Lado Lindner J., Cronje P.J.R., Rodrigo M.J., and Zacarías L. 

Assessment of antioxidant compounds during storage period of ‘Valencia’ orange fruit 

Sharifani M.M., Mohamadi Shamlou M., Daraei A., and Seifie E. 

Postharvest ethylene treatment reduces quality loss of stored mature ‘Navelate’ sweet 

orange 

Lafuente M.T., Alférez F., and Romero P. 

Organoleptic quality and preservation of tangerine fruits during cold storage in relation 

to application of waxes for postharvest 

Nascimento L.M., Machado M.A., Brito M.C.R., Moreira J., Brito P.C.N., and Sanches J.M. 

Effect of storage temperature on pitting development in satsuma ‘Okitsu’ 

Nuñez F.N., del Campo R.d.C., Pascale D.P., Díaz L.D., Solari J.S., Larrechart L.L., and Mara 

H.M. 

RNA-seq and phenylpropanoid metabolism of orange-Penicillium digitatum interaction 

Ballester A.R., Marcet-Houben M., Gabaldón T., Lafuente M.T., and González-Candelas 

L. 

Disruption of the chitin synthase gene PdigChsVII in the citrus postharvest pathogen 

Penicillium digitatum 

Gandia M., Harries E., and Marcos J.F. 

Proteins contributing to the pathogenicity of Penicillium digitatum towards citrus fruit 

Yamashita Y.K., Arimoto Y.A., Makino M.H., Annaka A.H., and Iida I.A. 

Identification and expression analysis of Penicillium digitatum genes involved in fungal 

virulence during citrus fruit infection 

de Ramón-Carbonell M., Ballester A.R., González-Candelas L., and Sánchez-Torres P. 

Metabolism of flavonoids and mycotoxins in citrus fruits infected by Alternaria alternata 

Del Río J. A., Díaz L., Ortuño A., García-Lidón A., and Porras I. 



S09P20 

S09P21 

S09P22 

S09P23 

S09P24 

S09P25 

S09P26 

S09P27 

S09P28 

S09P29 

S09P30 

S09P31 

S09P32 

S09P33 

S09P34 

S09P35 

S09P36 

Modulation of host responses by the biocontrol yeast Metschnikowia fructicola 

Hershkovitz V., Sela N., Rafael G., BenDayan C., Wisniewski M., and Droby S. 

Protein hydrolysates as resistance inducers for controlling Green Mould of citrus fruits 

Lachheb N., Sanzani S. M., Nigro F., Boselli M., and Ippolito A. 

Biochemical and transcriptomic changes associated with induced resistance in citrus 

fruit treated with sodium salts 

Youssef K., Sanzani S.M., Ligorio A., Fallanaj F., Nigro F., and Ippolito A. 

In vitro and in vivo antifungal activity of eight medicinal plants against Citrus Sour Rot 

agent Geotrichum candidum 

Talibi I., Askarne L., Boubaker H., Boudyach E.H., and Ait Ben Aoumar A. 

In vitro and in vivo antifungal activity of several Moroccan medicinal plants against 

Penicillium italicum, the causal agent of citrus Blue Mold 

Askarne L., Talibi I., Boubaker H., Boudyach E.H., Msanda F., Saadi B., Serghini M.A., and 

Ait Ben Aoumar A. 

Effects of fluorescent Pseudomonas and Bacillus sp. on Blue Mold of citrus caused by 

Penicillium italicum 

Askarne L., Talibi I., Boubaker H., Boudyach E.H., Msanda F., Saadi B., Serghini M.A., and 

Ait Ben Aoumar A. 

Practical impact of imazalil resistance on control of postharvest citrus Green and Blue 

Mould 

Erasmus A., Rikhotso V., Lesar K.H., Lennox C.L., and Fourie P.H. 

Effectiveness of the fungicide application system in the control of Penicillium digitatum 

in orange in Tucuman, Argentina 

Torres Leal G.J., Kamiya N., Carbajo M.S., Lacina M., and Farías M.F. 

Resistant strains to postharvest fungicides in Algarve citrus companies. Packinghouse 

sampling and in vivo assays 

Salazar M., Mendes S., and Nunes C. 

Influence of paraben concentration on the development of Green and Blue Molds on 

‘Valencia’ orange fruit 

Moscoso-Ramírez P.A., Montesinos-Herrero C., and Palou L. 

Selection and in vitro evaluation of yeasts for control of Geotrichum candidum 

Cunha T., Tosin E.S., And Kupper K.C. 

In vitro and in vivo evaluation of yeast isolates for biocontrol of Penicillium digitatum, 

causal agent of Green Mold 

Kupper K.C., Cunha T., And Tosin E.S. 

Optimal concentration of inoculum, types of injuries and control of Penicillium digitatum 

in orange fruits 

González-Fierro P., Nieto-Ángel D., Téliz-Ortiz D., Lara-Viveros F.M., and Orozco-Santos M. 

In vitro comparison of the effectiveness of disinfectants and a fungicide on the viability 

of spores of Geotrichum citri-aurantii. 

Diaz L.D., del Campo R.d.C., Peyrou M.P., and Mara H.M. 

Alternative treatments for postharvest decay control on ‘Ponkan’ tangerines 

Montero C.R.S., dos Santos L.C., Andreazza C.S., Schwarz L.L., and Bender R.J. 

Curative and protective control of Penicillium digitatum following imazalil application 

in aqueous dip and wax coating 

Njombolwana N.S., Erasmus A., and Fourie P.H. 

Fruit quality and storage potential of ‘Kinnow’ mandarin (Citrus reticulata) in relation to 

different geographical locations of Pakistan 

Khalid M.S., Malik A.U., Amin M., Khalid S., Asad H.U., Raza S.A., and Malik O.H. 



S09P37 

S09P38 

Effect of organic and inorganic salts as alternative strategy for the control of the 

postharvest Citrus Sour Rot agent Geotrichum candidum 


Lemon fruits from endochitinase transgenic plants exhibit resistance against postharvest 

fungal pathogens 

Oliveri C., Distefano G., La Malfa S., La Rosa R., Deng Z., and Gentile A. 

SESSION 10: Watering and nutrition 


Poster session on Thursday 22 nd 

Conveners: Dr. Diego INTRIGLIOLO (Instituto Valenciano Investigaciones Agrarias, Spain) and Dr. Dirceu 

DE MATTOS Jr. (Centro de Citricultura Sylvio Moreira, Brazil) 

Oral ID Title 

S10O01 

S10O02 

S10O03 

S10O04 

S10O05 

S10O06 

S10O07 

S10O08 

S10O09 

S10O10 

Open hydroponics of citrus compared to conventional drip irrigation best practice: first 

three years of trialling and Australian experience 

Falivene S., Navarro Acosta J.M., and Connolly K. 

Deficit irrigation strategies: preliminary assessment on a Sicilian young orange orchard 

Stagno F., Parisi R., Cirelli G., Consoli S., Roccuzzo G., Barbagallo S., and Intrigliolo F. 

Citrus water use in South Africa 

Vahrmeijer J.T., Annandale J.G., Gush M.B., and Taylor N.J. 

Evapotranspiration over an irrigated orange orchard using micrometeorological 

techniques and sap flow measurements 

Consoli S., Continella A., Motisi A., Papa R., and Pasotti L. 

Partial root-zone drying effects under different rootstocks and irrigation systems in 

Valencia, Spain 

Ortega J., Forner-Giner M.A., Quiñones A., Legaz F., and Intrigliolo D.S. 

A critical evaluation of citrus leaf mineral status guidelines for optimal yield in Israel 

Raveh E. 

What limits nitrogen fertilization responses of fertigated citrus orchards under tropical 

conditions? 

Mattos Jr. D., Quaggio J.A., Boaretto R.M., Souza T.R., and Zambrosi F.C.B. 

Uptake of 44 Ca and 15 N by young citrus trees 

Quiñones A., Martínez-Alcántara B., Alcayde E., and Legaz F. 

A new approach to front citrus iron chlorosis: organo-mineral fertilizers from glass-matrix 

and organic biomasses 

Torrisi B., Trinchera A., Allegra M., Epifani R., Marcucci A., Roccuzzo G., Intrigliolo F., and 

Rea E. 

Nitrogen and calcium equilibrium on citrus nutrition 

Quaggio J.A., Souza T.R., Boaretto R.M., Zambrosi F.C.B., and Mattos Jr. D. 



S10P01 

S10P02 

S10P03 

S10P04 

S10P05 

S10P06 

S10P07 

S10P08 

S10P09 

S10P10 

S10P11 

S10P12 

S10P13 

S10P14 

S10P15 

S10P16 

S10P17 

Physiological and nutritional responses of navel orange trees to different irrigation and 

fertigation practices 

Navarro J.M., and Falivene S. 

Influence of precipitation in the fruit growing season on sugar accumulation in satsuma 

mandarin fruit juice 

Takishita F., Uchida M., Hiraoka K., and Nesumi H. 

Recover of plugged drippers in orange grove irrigation system using mechanical and 

chemical techniques 

Fachini E., Junqueira Franco A.C.B., and Galbiatti J.A. 

Effect of Sunred metabolic promoter and deficit irrigation on fruit quality of Valencia 

oranges 

Massenti R., Barone F., Farina V., and Lo Bianco R. 

Foliar and root application of potassium nitrate and calcium nitrate to Citrus 

macrophylla seedlings under NaCl stress 

Navarro J.M., Andujar S., and Rodríguez Morán M. 

Effect of mulching and drip irrigation on satsuma mandarin fruit quality in a volcanic 

ash soil 

Han S.G., Kim Y.H., Moon Y.E., and Kang S.B. 

Tree-to-tree variation in plant-based measurements as indicators of orange water 

status 

Motisi A., Continella A., Massenti R., and Romolo F. 

Predicting the impact of the climatic variability in the necessities of watering of the 

grapefruit in the Island of the Youth in Cuba 

Cueto J.C., Pardo A.P., and Durán G.D. 

Effect of regulated deficit irrigation on vegetative growth, fruiting, stomatal 

conductance, leaf proline content and water use efficiency for Nules clementine 

grown in the Souss valley of Morocco 

Bagayogo S., El-Otmani M., El-Fadl A., and Benismail M.C. 

Response of Star Ruby grapefruit trees to deficit irrigation during different stages of fruit 

growth: effects on water relations, yield and fruit quality 

Pérez-Pérez J.G., Robles J.M., García-Oller M.I., and Botía P. 

Water relations and productivity of Natal orange plants under controlled deficit 

irrigation in São Paulo State, Brazil 

Pires R.C.M., Silva A.L.B.O., Ribeiro R.V., Quaggio J.A., Lima M.A.F., and Zani M.L. 

Responses of Nules clementine trees to deficit irrigation under different rootstocks. Tree 

performance and fruit quality 

Ortega J., Molina M.D., Intrigliolo D.S., De Miguel A., Bonafé C., Valero J.L., Peiró E., and 

Forner-Giner M.A. 

Root distribution of orange trees under two different drip irrigation systems 

Fachini E., and Galbiatti J.A. 

The effect of herbicide treatments on soil nutrient availability and plant nutritional 

status in a citrus garden 

Wu C.Q., Liao C.X., Ou Y., and Xie Y.H. 

Efficiency of zinc (68Zn) fertilizers applied to the soil with citrus 

Boaretto R.M., Hippler F.W.R., Quaggio J.A., Boaretto A.E., Abreu Jr. C.H., and Mattos Jr. D. 

Interaction of magnesium in calcium uptake in young citrus trees 

Martínez-Alcántara B., Quiñones A., Alcayde E., and Legaz F. 

Study on the relationship between fruit quality, soil nutrient availability and tree 

nutritional status 

Lu X.P., Huang C.N., Xiao Y.M., Nie Q., Zhao X.L., and Xie S.X 



S10P18 

S10P19 

S10P20 

S10P21 

S10P22 

S10P23 

S10P24 

S10P25 

S10P26 

S10P27 

S10P28 

S10P29 

S10P30 

Boron supply affects growth of citrus and correlates with hydraulic conductivity and 

gas exchange of rootstock varieties 

Mesquita G.L., Mattos Jr. D., Ribeiro R.V., Boaretto R.M., and Quaggio J.A. 

Silicon uptake in citrus and the validation of an analytical method 

Vahrmeijer J.T., Asanzi N.M., and Taylor N.J. 

Phosphorus deficiency decreases nutrient use efficiency of citrus 

Zambrosi F.C.B., Mattos Jr. D., Quaggio J.A., and Boaretto R.M. 

Enhancement yield, fruit quality and nutritional status of ‘Washington’ navel orange 

trees by application of some biostimulants 

El-Shazly S.M., and Mustafa N.S. 

Calcium, magnesium and potassium levels in the soil and in the leaf of orange trees 

on different rootstocks and soil conservation systems in the northwest of Paraná State, 

Brazil 

Gil L. G., Auler P. A. M., and Pavan M.A. 

Response of clementine citrus to foliar potassium fertilization: effects on fruit production 

and quality 

Hamza A., El Guilli M., Bamouh A., Zouahri A., Bouabid R., and Lfadili R. 

Impact of biostimulant substances on growth of ‘Washington’ navel orange trees 

Mustafa N.S., and El-Shazly S. M. 

Foliar nutrition with macronutrients for ‘Valencia’ orange and ‘Murcott’ tangor trees 

Rodríguez V.A., Alayón Luaces P., Píccoli A.B., Chabbal M.D., Giménez L.I., and Martínez 

G.C. 

Effects of nutritional trunk injections on sweet orange production 

Martínez G.C., Alayón Luaces P., Yfran Elvira M.M., Chabbal M.D., Mazza S.M., and 

Rodríguez V.A. 

Influence of reduced rate of application of phosphorus and potassium fertilizers on soil 

and fruit quality in a Satsuma mandarin orchard 

Yoshikawa K.Y., Nakamura A.N., Baba A.B., and Kusaba S.K. 

Potassium leaching from young lysimeter-grown orange trees 

Boman B. J., and Battikhi A.M. 

Effect of organic fertilization on soil organic matter and on root apparatus of citrus trees 

Trinchera A., Torrisi B., Allegra M., Rinaldi S., Rea E., Intrigliolo F., and Roccuzzo G. 

Use of plant-soil-atmosphere sensors on a young clementine mandarin orchard under 

regulated deficit irrigation to monitor changes in water relations for better irrigation 

scheduling 

El-Otmani M., El-Fadl A., and Benismail M.C. 

SESSION 11: Cultural practices and mechanization 



Conveners: Dr. Enrique MOLTÓ (Instituto Valenciano Investigaciones Agrarias, Spain) and Dr. Mohamed 

EL-OTMANI (Complexe Horticole d’Agadir, Morocco) 

Oral ID Title 

S11O01 

S11O02 

New method of citrus grafting by the use of laboratory tape (top budding) 

Kitamura M., Caisley J., Sakaki H., Fujita K., and Takahara T. 

Performance of citrus nursery trees and two-year older trees after transplantation in 

the field 

Zekri M. 


Oral ID Title 

S11O03 

S11O04 

S11O05 

S11O06 

S11O07 

S11O08 


S11P01 

S11P02 

S11P03 

S11P04 

S11P05 

S11P06 

S11P07 

S11P08 

S11P09 

S11P10 

S11P11 

Effect of inarched, two-rootstock trees on development and yield of ‘Valencia’ orange 

orchards 

De Lima J. E. O., and de Lima J. E. P. 

Morphological and yield characteristics of ‘Washington’ navel orange and ‘Tahiti’ lime 

trees produced with buds from floral versus vegetative mother shoots 

Lovatt C.J., and Krueger R.R. 

Effect of different pruning severities on incidence of creasing and fruit quality in sweet 

orange 

Hussain Z., Singh Z., and Mandel R. 

Reduction of fruit splitting and the incidence of creasing of ‘Nova’ mandarin and 

‘Washington’ navel orange by NAA sprays 

Greenberg J., Kaplan I., Tagari E., Fainzack M., Egozi Y., and Giladi B. 

On-farm citrus trials in Australia: Effective extension for commercial assessment 

Falivene S., Connolly K., and Cannard M. 

Evolution of citrus mechanical harvesting in Florida – Lessons for the future 

Roka F.M. 

Study on mushroom dregs application in citrus nursery 

Guan B., Chen K.L., He J., and Liu J.J. 

Effect of soil preparation systems, mulching and rootstocks on ‘Pera’ orange (Citrus 

sinensis) performance in the northwest of Parana State, Brazil 

Auler P.A.M., Fidalski J., Gil L.G., and Pavan M.A. 

Evaluation of rootstocks for the ‘Tahiti’ lime in the municipality of Jaíba, Brazil 

Alves R.R., Machado D.L.M., Salomão L.C.C., Siqueira D.L., and Silva S.D.R. 

Development and production of ‘Tahiti’ lime IAC-5 grafted on ‘Flying Dragon’ (Poncirus 

trifoliata var. monstrosa), grown in high planting densities 

Machado D.L.M., Alves R.R., Siqueira D.L., Salomão L.C.C., and Silva S.D.R. 

Effect of shade screen on production, fruit quality and growth parameters in ‘Fino 49’ 

lemon trees grafted on Citrus macrophylla and sour orange 

Gimeno V., Simón I., Martínez V., Lidón V., Shahid M.A., and García-Sánchez F. 

Effect of liquid fertilizer applied by injection into the soil on quality of ‘Tarocco’ blood 

orange 

He J., Chen K.L., Guan B., and Liu J.J. 

Effect of branch girdling and ringing on carbohydrates, chlorophyll fluorescence and 

SPAD index in leaves of ‘Tahiti’ acid lime 

Santos D., Siqueira D.L., Salomão L.C.C., and Cecon P.R. 

Production of ‘Tahiti’ acid lime after branch girdling or ringing 

Santos D., Siqueira D.L., Salomao L.C.C., and Cecon P.R. 

Horticultural package for high quality ‘Tahiti’ lime production 

Mourão Filho F.A.A., Stuchi E.S., Cantuarias-Avilés T., Espinoza-Núñez E., Bremer Neto H., 

Bassan M.M., and Silva S.R. 

Field evaluation of two canopy shake systems, OXBO 3210 and OXBO 3220, on citrus 

orchards in Andalusia (Spain) 

Arenas Arenas F.J., Salguero A., and Hervalejo A. 

Production seasonality of ‘Tahiti’ lime in three consecutive harvests under semiarid 

climatic conditions 

Maia V.M., Álvarez J.M., Oliveira F.S., Gomes F.H.C., Azpiazú I., and Salles B.P.A. 



S11P12 

S11P13 

S11P14 

S11P15 

S11P16 

S11P17 

S11P18 

S11P19 

S11P20 

S11P21 

S11P22 

Enhancement of citrus value chain production in Pakistan and Australia under the 

AusAid Program 

Khurshid T., Ahmad I., Jaskani M.J., Nabi G., Tahir T., Ali W., Rahman A., Khan M.A., and 

Rahman H. 

Technology and production costs for organic versus conventional ‘Navelina’ citrus 

orchards 

Reis D., Marreiros A., Fernandes M.M., Mourão I., and Duarte A. 

Prediction of moving northward of favorable regions to cultivate subtropical citrus by 

estimation of changes in annual mean and minimum air temperature in Japan 

Sugiura T., Sakamoto D., Sugiura H., Koshita Y., and Asakura T. 

INTA´s Citrus Improvement Program 

Costa N., Plata M.I., and Anderson C. 

Labor-saving practices for ‘Shatangju’ mandarins in China 

Ma P.Q., and Wu W. 

FruTIC: An information and communication tool for an integrated health management 

of citrus groves 

Garrán S.M., Stablum A., Franco S., Ibarrola S., Mika R., Milera S., and Marnetto S. 

A phytosanitary evaluation method (MEF) for commercial citrus groves 

Garrán S.M., Mika R., Boca R.T., Beribe M.J., and Pérez A. 

Micro budding of commercial citrus cultivars of India 


Evaluation of organic growing media and bio-control agents in the production of 

certified citrus rootstocks 

Yaseen T., Dongiovanni C., Roccuzzo G., Ippolito A., and DÓnghia A.M. 

The diversification of agriculture in the new Cuban citriculture 

Cueto J.C., Piñero J.P., Ortega I.O., and Torres L.T. 

Presence of weed biotypes with suspected resistance to glyphosate in agroecosystem 

citrus orchards in Cuba: a latent threat 

Otero L., and De Pardo R. 

SESSION 12: Citrus HLB and other bacterial diseases 

Oral presentations at Auditorium 1, on Thursday 22 nd from 11:30 to 17:00. 


Conveners: Dr. María M. LÓPEZ (Instituto Valenciano Investigaciones Agrarias, Spain), Dr. Olivier PRUVOST 

(Centre de cooperation Internationale en Recherche Agronomique pour le Développement, France) 

and Dr. Yongping DUAN (U. S. Department of Agriculture - Agricultural Research Service, USA). 

Oral ID Title 

S12O01 

S12O02 

S12O03 

New insights into the Citrus Huanglongbing complex and potential solutions to this 

devastating disease 

Duan Y.P., Zhou L.J., Zhang M.Q., Vahling-Armstrong C., Hao G.X., Zou H.S., and Hoffman M. 

Tissue-print and squash real-time PCR for direct detection of Candidatus Liberibacter 

spp. in citrus plants and insect vectors 

Bertolini E., Lopes S., Felipe R.T.A., Teresani G., Mourão F.A.A., Colomer M., Bové J.M., 

López M.M., and Cambra M. 

A new insect vector of Candidatus Liberibacter asiaticus, Cacopsylla (Psylla) citrisuga 

(Hemiptera: Psyllidae) 

Cen Y., Gao J., Deng X., Xia Y., Chen J., Zhang L., Guo J., Gao W., Zhou W., and Wang Z. 


Oral ID Title 

S12O04 

S12O05 

S12O06 

S12O07 

S12O08 

S12O09 

S12O10 

S12O11 

S12O12 

S12O13 

S12O14 


S12P01 

S12P02 

S12P03 

S12P04 

S12P05 

S12P06 

On the identity of orange jasmine and its relevance to Huanglongbing and Diaphorina 

citri 

Holford P., Nguyen C.H., Beattie G.A.C., Haigh A.M., Hasick N.J., Mabberley D.J., Weston 

P.H. 

Effect of HLB on the expression of calcium signals related genes 

Parra C.C., Kunta M., and Louzada E.S. 

Transcriptional genomics and proteomics in citrus roots infected by Candidatus 

Liberibacter asiaticus 

Zhong Y. 

Resistance and tolerance to Huanglongbing in Citrus 

Stover E., McCollum G., Driggers R., Duan Y.P., Shatters Jr. R., and Ritenour M. 

A comparison of different methods to evaluate host resistance or tolerance to 

Huanglongbing, caused by Candidatus Liberibacter asiaticus 

Bowman K.D., and Albrecht U. 

Evaluation of transgenic citrus for disease resistance to HLB and Canker 

Dutt M., Barthe G.A., Orbovic V., Irey M., and Grosser J.W. 

California’s response to the first detection of HLB 

Luque-Williams M.J. 

Comparative study of different host range strains of Xanthomonas citri subsp. citri: 

Chemotaxis and biofilm formation 

Sena M., Ferragud E., Redondo C., Johnson E.G., Graham J.H., Girón J.A., and Cubero J. 

A new minisatellite-based scheme for the global surveillance of Xanthomonas citri 

subsp.-citri, the causal agent of Asiatic Citrus Canker 

Magne M., Leduc C., Vernière C., Vital K, Gordon J., Escalon A., Guérin F., Gagnevin L., 

and Pruvost O. 

Analysis of microRNAome of Chinese citron ‘C-05’ resistant to Citrus Canker disease 

Dai S.M., Chen Y.M., Li D.Z., Li F., Yan J.W., and Deng Z.N. 

The role of auxin in the citrus defense to early infection by Xylella fastidiosa 

Rodrigues C.M., Souza A.A., Takita M.A., and Machado M.A. 

Yield loss modeling of Candidatus Liberibacter asiaticus on Persian lime (Citrus latifolia) 

in southern Mexico 

Flores Sanchez J.L., Mora Aguilera G., Loeza Kuk E., Domínguez Monge S., Acevedo 

Sánchez G., and López Arroyo J.I. 

Seasonal detection of Huanglongbing symptomatic trees and Diaphorina citri in citrus 

groves in Sao Paulo State, Brazil 

Bassanezi R.B. 

Identification of Candidatus Liberibacter and phytoplasma and evaluation of their 

association with Citrus Huanglongbing in China 

Su H.N., Wang X.F., Tang K.Z., Li Z.A., and Zhou C.Y. 

Rapid on site detection of the HLB/Citrus Greening causal agent Candidatus Liberibacter 

asiaticus by AmplifyRP, a novel rapid isothermal nucleic acid amplification platform 

Russel P., Amato M.A., and Bohannon R. 

Diversity of Candidatus Liberibacter asiaticus, Candidatus Liberibacter africanus and 

Candidatus Liberibacter americanus based on 23S/5S rDNA sequences 

Liao H., Bai X., Li Y., Chen C., Yang L., Xu N., Huang H., and Wang X. 

Phloem anatomy of citrus trees: healthy vs. Greening 

Etxeberria E., and Narciso C. 



S12P07 

S12P08 

S12P09 

S12P10 

S12P11 

S12P12 

S12P13 

S12P14 

S12P15 

S12P16 

S12P17 

S12P18 

S12P19 

S12P20 

S12P21 

S12P22 

Anatomical comparison of HLB-affected sweet orange and rough lemon 

Fan J., Chen C., Gmitter Jr. F.G., Achor D.S., Brlansky R.H., and Li Z.G. 

The significance of early root infection in Huanglongbing disease development and 

crop loss 

Johnson E.G., Bright D.B., and Graham J.H. 

Monitoring the Candidatus Liberibacter asiaticus in a commercial orchard of sweet 

orange and Tahiti lime in the northwest of Paraná State 

Sauer A.V., Nocchi P.T.R., Zanutto C.A., Rinald D.A.M.F., and Nunes W.M.C. 

Multiplication of Candidatus Liberibacter asiaticus in Citrus sinensis, Citrus sunki, Poncirus 

trifoliata and hybrids obtained from crosses between Citrus sunki and Poncirus trifoliata 

Boava L.P., Cristofani-Yaly M., Coletta Filho H.D., Bastianel M., and Machado M.A. 

Low titers of Candidatus Liberibacter asiaticus in citrus plants exposed to high 

temperatures result in low acquisition rates of the bacterium by the insect vector 

Diaphorina citri 

Lopes S.A., Luiz F.Q.B.Q., Martins E.C., Fassini C.G., and Sousa M.C. 

Pre-inoculacion with virus and citrus viroids in Candidatus Liberibacter infection and 

HLB symptoms 

Carvalho S.A., Silva L.F.C., Souza M.C.S., Francisco, C.S., and Coletta-Filho H.D. 

The efficient transmission of Candidatus Liberibacter americanus from periwinkle 

(Catharanthus roseus) to different citrus genotypes by dodder 

Francisco C.S., Locali E.C., Machado M.A., and Coletta-Filho H.D. 

Population dynamics of Diaphorina citri Kuwayama (hemiptera: psyllidae) in orchards 

of valencia sweet orange, Ponkan mandarin and Murcott Tangor Trees 

Beloti V.H., Felippe M.R., Rugno G.R., Carmo-Uehara A. do, Garbim L.F., Godoy W.A.C., 

and Yamamoto P.T. 

Systemic insecticides are effective in preventing the transmission of Candidatus 

Liberibacter asiaticus by Diaphorina citri Kuwayama? 

Yamamoto P.T., Miranda M.P de, and Felippe M.R. 

Vector control and foliar nutrition for management of huanglongbing in Florida citrus 

Stansly P.A., Arevalo H.A., Qureshi J.A., Jones M., Hendricks K., Roberts P.D., and Roka F.M. 

Foliar spray of nutrients and growth regulators on the management of citrus affected 

by HLB – Is it possible? 

Medina C.L., Bataglia O.C., Furlani P.R., Machado R.S., and Creste A. 

Antibiotic therapy of citrus bud wood for the management of Huanglongbing disease 

Yaqub M.S., and Khan I.A. 

Reduction of Huanglongbing in the project of appropriate techniques expansion for 

the cultivation of king mandarin (Citrus nobilis) in Southern Vietnam 

Yuasa K.Y., Nguyen V.H.N., and Ichinose K.I. 

Heat treatment of Huanglongbing–affected citrus trees in field for reduction of 

Candidatus Liberibacter asiaticus 

Deng X.L., Guan L. , Liang M.D. , Xu M. R., Xia Y. L. , Sequeira R. , and Chen J.C. 

Gas exchanged and water relations of ‘Valencia’ oranges trees infected with 

Huanglongbing (HLB, ex greening) 

Saccini V.A.V., Medina C.L., Santos D.M.M., Machado R.S., and Silva J. 

Assessing plant health risk in relation to Xanthomonas citri strains causing citrus bacterial 

canker and evaluating measures for managing this risk 

Holeva M., Olivier V., Hostachy B., Smith J., MacLeod A., and Pruvost O. 



S12P23 

S12P24 

S12P25 

S12P26 

S12P27 

S12P28 

S12P29 

S12P30 

S12P31 

S12P32 

S12P33 

S12P34 

S12P35 

S12P36 

S12P37 

S12P38 

Characterization of a new Xanthomonas citri subsp. citri isolate which triggers a hostspecific 

response 

Roeschlin R.A., Chiesa M.A., Enrique R., Favaro M.A., Torres P.S., Filippone M.P., Gmitter Jr. 

F.G., Vojnov A.A., Castagnaro A.P., Marano M.R., and Gadea J. 

Analysis of genetic diversity of Xanthomonas citri subsp citri strains. Characterization of 

a new isolate which triggers a host-specific response 

Siciliano M.F., Chiesa M.A., Ornella L., Pino Delgado N., Favaro M.A., Sendín L.N., Roeschlin 

R.A., Orce I.G., Ploper L.D., Vojnov A.A., Filippone M.P., Castagnaro A.P., and Marano M.R. 

The causal agent of Citrus Canker, Xanthomonas citri subsp. citri, enters in a reversible viable 

but non culturable state induced by copper, that can be reverted by citrus leaf extract 

Golmohammadi M.G., Llop P-Ll., Cubero J.C., and Lopez M.M.L. 

Effect of N-acetyl-L-cysteine (NAC) on the epiphytic fitness of Xanthomonas citri subsp. 

citri (Xcc) in sweet orange 

Picchi S.C., Inui-Kishi R.N., Takita M.A., Machado M.A., and De Souza A.A. 

Disruption of ParB alters the virulence of Xanthomonas citri subsp. citri 

Ucci A.P.U., and Ferreira H.F. 

Analysis of microRNAs involved in defense response signaling against Xanthomonas 

spp. in Citrus limon 

Chiesa M.A., Torres P.S., Campos L., Roeschlin R.A., Gerhardt N., Filippone M.P., Conejero 

V., Castagnaro A.P., Vojnov A.A., Gmitter Jr. F.G., Gadea J., and Marano M.R. 

Influence of different copper hydroxide spray volumes and doses to control Citrus 

Canker in lemon in Tucumán, Argentina 

Salas López H., Mansilla C., Stein B., Rojas A., and Figueroa D. 

Control of Citrus Canker (Xanthomonas citri subsp. citri) mediated by neonicotinoids in 

combination with acibenzolar-S-methyl and copper 

Barreto T.P., Pozzan M., and Leite R. 

Activity of antimicrobial peptides (AMPs) against Xanthomonas citri subsp. citri (Xcc) 

in Citrus sinensis ‘Baía’ 

Inui-Kishi R.N., Freitas-Astua J., Picchi S.C., Brand G.D., Bloch Jr C., Falcao A.O., Stach- 

Machado D., Cilli E.M., and Machado M.A. 

Bacteriostatic and bactericidal activity of different essential oils to alternative control 

in vitro of Xanthomonas citri subsp. citri 

Sauer A.V., Santos E.M., Zuliani-Gonçalves A.M.O., Nocchi P.T.R., Nunes W.M.C., and 

Bonato C.M. 

Canker control by the siderophore Pyochelin from Pseudomonas fluorescens 

Adler C., Lami MJ., de Cristobal RE., Filippone MP., Castagnaro AP., and Vincent P.A. 

Genetic response of sweet orange treated with chitosan to the infection of Xylella 

fastidiosa 

Coqueiro D.S.O., Rodrigues C.M., Souza A.A., Takita M.A., Kishi L.T., and Machado M.A. 

Genetic variation of California Spiroplasma citri populations revealed by two genetic loci 

Wang X., Doddapaneni H., Chen J. C., and Yokomi R. K. 

Serological detection of Spiroplasma citri using a bacterial secreted protein as the 

detection marker 

Shi J.S., Pagliaccia P.D., Morgan M.R., Ma W.M., and Vidalakis G. 

Witches Broom Disease of Lime, a serious disease of acid lime (Citrus aurantifolia) in the 

Arabian Peninsula 

Al-Sadi A.M., AL-Yahyai R.A., and Al-Said F.A. 

Portable chemical sensors for monitoring infection-specific volatiles in asymptomatic citrus 

Fink R.L., Aksenov A.A., Thuesen L.H., Pasamontes A., Cheung W.H.K., Peirano D.J., and 

Davis C.E. 



S12P39 

S12P40 

S12P41 

S12P42 

S12P43 

S12P44 

SESSION 13: Fruit flies 

Unforbidden fruits: preventing citrus smuggling by introducing varieties culturally 

significant to ethnic communities 

Karp D., Siebert T., Vidalakis G., Krueger R.R., Lee R.F., and Kahn T. 

Introduction of control on main citrus disease in P. R. China 

Zhou C.Y. 

Gaining experience with exotic citrus pest and disease threats to Australia through 

collaborative work in Bhutan 

Sanderson G., Hardy S., Donovan N., Beattie A., Holford P., Dorjee D., Wangdi P., Thinlay 

T., and Om N. 

Nucleotide sequence analysis of ribosomal protein gene sub-units (rplA-rplJ ) of 

Candidatus Liberibacter asiaticus infecting different citrus cultivars in Maharastra, India 

Ghosh D.K., Bhose Sumit, and Gowda S. 

Analysis of Citrus Huanglonbing spatial dynamics in non-intervened groves of Cuba by 

Spatial Analysis by Distance Indices (SADIE) 

Batista L., Peña I., Luis M., Acosta I., Hernández L., Llauger R., Casín J.C., and Laranjeira 

F.F. 

Identification of tolerance in citrus germplasm for Huanglongbing 




Conveners: Dr. Beatriz SABATER-MUÑOZ (Instituto Valenciano Investigaciones Agrarias, Spain) and Dr. 

Jorge HENDRICHS (International Atomic Energy Agency – Food and Agriculture Organization, Austria) 

Oral ID Title 

S13O01 

S13O02 

S13O03 

S13O04 

S13O05 

S13O06 

S13O07 

Application of the Sterile Insect Technique: an effective biological control method 

against fruit fly pests and its contribution to food security, the environment and trade 

Hendrichs J., Pereira R., and Reyes J. 

Assessing the effectiveness of sterile males in Mediterranean fruit fly population 

reduction by molecular techniques 

Juan-Blasco M., Sabater-Muñoz B., Argiles R., Jacas J.A., Castañera P., and Urbaneja A. 

Multiple insecticide resistance traits in a field derived population of the Mediterranean 

fruit fly, Ceratitis capitata 

Ortego F., Couso-Ferrer F., Arouri R., Huertas-Rosales O., Beroiz B., Perera N., Cervera A., 

Hernández-Crespo P., and Castañera P. 

Citrus fruits and the Mediterranean fruit fly 

Papadopoulos N.T., Papachristos D.P., and Ioannou C.S. 

Looking inside the chemosensory system of the medfly Ceratitis capitata 

Malacrida A.R., Gomulski L.M., Scolari F., Falchetto M., Siciliano P., Manni M., and Gasperi 

G. 

Field infestation and suppression of the invasive fruit fly Bactrocera invadens on citrus 

in Kenya 

Ekesi S 

Quarantine mitigation for Tephritid fruit fly pests in citrus 

Liquido N. J., and Griffin R. L. 



S13P01 

S13P02 

S13P03 

S13P04 

S13P05 

S13P06 

S13P07 

S13P08 

S13P09 

S13P10 

S13P11 

S13P12 

S13P13 

S13P14 

S13P15 

The transcriptome and protein baits of Bactrocera dorsalis (Diptera: Tephritidae) 

Zheng W., Zhang W., and Zhang H. 

The potential benefits of using engineered Medfly to improve the efficacy and to 

reduce the cost of the Sterile Insect Technique: RIDL strain OX3864A 

Slade G., Koukidou M., Leftwich PT., Rempoulakis P., Economopoulos A., Vontas J., and 

Alphey L. 

An early step toward the development of a method to predict Mediterranean fruit fly 

adult emergence under different soil moisture and temperature regimes 

Garrido-Jurado I., Valverde-García P., and Quesada-Moraga E. 

Fruit flies in orange plantations of TicoFrut - Costa Rica 

Camacho H. 

Role of phytosanitary surveillance of Anastrepha spp fruit flies (Diptera: Tephritidae) in 

the context of the citrus industry of Cuba 

Borges Soto M., Beltrán Castillo A., Avalos Rodriguez Y., Hernandez D., Sabater-Muñoz B., 

and Rodriguez Rubial M. 

DECIS TRAP MedFly®: innovative platform technology for the sustainable management 

of the Mediterranean fruit fly (Ceratitis capitata) 

Wirtz K., Ramos E., and Fullana J. 

Potential of secondary metabolites secreted by the entomopathogenic mitosporic 

ascomycetes Beauveria sp. and Metarhizium spp. for medfly Ceratitis capitata adult 

control 

Lozano-Tovar M.D., Garrido-Jurado I., and Quesada-Moraga E. 

Comparison of different food attractants for fruit fly capture (Diptera: Tephritidae) in 

citrus orchards in the state of São Paulo, Brazil 

Rodrigues M.D.A., Raga A., Maldonado Jr. W., and Barbosa J.C. 

Evaluation of protein bait laced with various insecticides on the Queensland Fruit Fly 

(Diptera: Tephritidae): Attraction, feeding, mortality and bait persistence 

Mahat K., and Drew R.A.I 

Effectiveness evaluation of two attractants, CeraTrap® and Tripack®, for the mass 

trapping of Ceratitis capitata (Diptera: Tephritidae) in citrus orchards in different regions 

of Tunisia 

Hafsi A., Rahmouni R., Ben Jannet M., Harbi A., and Chermiti B. 

Field releases of the larval parasitoid Diachasmimorpha longicaudata in Spain: first 

results on dispersal pattern 

Harbi A., Beitia F., Tur C., Chermiti B., Verdú M.J., and Sabater-Muñoz B. 

Magnet ® MED: A new long-life, ready-to-use Attract and kill system to control 

Mediterranean fruit fly, Ceratitis capitata Wiedemann 

Colás C., Dominguez M., Marti S., and Alfaro C. 

Assessment of the efficacy of lure and kill devices for the control of Mediterranean fruit 

fly in citrus orchards 

Navarro-Llopis, V., Primo Millo, J., Vacas, S. 

Evaluation of mass trapping technique for control of Ceratitis capitata Wiedemann 

(Diptera: Tephritidae) in citrus orchards of Northern Iran 

Mafi Pashakolaei S. 

The seasonal population dynamics of Ceratitis capitata Wiedemann (Diptera: 

Tephritidae) and fruit damage on horticultural crops in Northern Iran 



SESSION 14: Virus and virus like diseases 

Oral presentations at Room 4, on Tuesday 20 th from 10:30 to 13:30 


Conveners: Dr. Pedro MORENO (Instituto Valenciano Investigaciones Agrarias, Spain) and Dr. William 

O. DAWSON (Citrus Research and Education Center, USA). 

Oral ID Title 

S14O01 

S14O02 

S14O03 

S14O04 

S14O05 

S14O06 

S14O07 

S14O08 

S14O09 

S14O10 

S14O11 


S14P01 

S14P02 

S14P03 

Recent developments on Citrus tristeza virus research 

Folimonova S. 

Large scale survey of Citrus tristeza virus (CTV) and its aphid vectors in Morocco 

Afechtal M., Djelouah K., Cocuzza G., and D’Onghia A.M. 

Capillary electrophoresis-single–strand conformation polymorphisms and multiple 

molecular marker genotyping allow a rapid differentiation of CTV isolates 

Licciardello G., Russo M., Daden M., Bar-Joseph M., and Catara A. 

Genetic and biological stability of Citrus tristeza virus (CTV) infecting the non-natural 

host Nicotiana benthamiana 

Navarro-López J., Ruiz-Ruiz S., Moreno P., and Ambrós S. 

Citrus tristeza virus enhances the titer of Citrus dwarfing viroid in co-infected ‘Mexican’ 

lime plants through p23 expression 

Serra P., Bani Hashemian S.M., Fagoaga C., Romero J., Bertolini E., Ruiz-Ruiz S., Gorris M.T., 

and Durán-Vila N. 

The p23 protein encoded by Citrus tristeza virus: fine dissection of its determinants for 

nucleolar localization and for suppression of RNA silencing and pathogenesis 

Ruiz Ruiz S., Soler N., Sánchez-Navarro J., Fagoaga C., López C., Navarro L., Moreno P., 

Peña L., and Flores R. 

Viruliferous Brevipalpus phoenicis gradient from Citrus Leprosis trees 

Bassanezi R.B., Montesino L.H., and Novelli V.M. 

New generation sequencing platforms for detection and characterization of viruses 

and viroids in citrus 

Olmos A., Bertolini E., Varveri C., Candresse T., Martínez M.C., Pina J.A., and Cambra M. 

Deep sequencing of viroid-derived small RNAs from citron 

Cao M.J., Su H.N., Yang F.Y., Chen H.M., and Zhou C.Y. 

The complete genome sequence of Citrus vein enation virus (CVEV) obtained through 

deep sequencing of small RNAs 

Vives M.C., Velázquez K., Pina J.A., Moreno P., Guerri J., and Navarro L. 

Deep sequencing of citrus affected by graft-transmissible diseases of unknown 

aetiology leads to discovery of two novel viruses 

Loconsole G., Giampetruzzi A., Saldarelli P., Onelge N., Yokomi R.K., and Saponari M. 

Genetic variation of Citrus tristeza virus (CTV) isolates from Calabria, Italy 

Fontana A., Debreczeni D., Albanese G., Davino S., Flores R., and Rubio L. 

Incidence, distribution and first identification of Citrus tristeza virus by RT-PCR in citrus 

orchards in South Western Nigeria 

Adediji A.O., Atiri G.I., and Kumar P.L. 

A rapid procedure to evaluate the protecting ability of Citrus tristeza virus mild isolates 

against severe isolates 

Ruiz Ruiz S., Navarro-López J., Moreno P., and Ambrós S. 



S14P04 

S14P05 

S14P06 

S14P07 

S14P08 

S14P09 

S14P10 

S14P11 

S14P12 

S14P13 

S14P14 

S14P15 

S14P16 

S14P17 

S14P18 

Expression of different proteins in sweet orange induced by severe and mild Citrus 

tristeza virus (CTV) isolates 

Yang F.Y., Li Z.A., Zhou C.Y., and Zhou Y. 

Screening of Citrus tristeza virus in sweet oranges and limes of the Colombian Citrus 

Collection (Corpoica - Meta) 

Guzmán-Barney M.M., Rodríguez P., Ordúz J., and Martínez J. 

Molecular diversity of Citrus tristeza virus strains collected over the past 50 years and 

maintained in planta collections in California 

Wang J.W., Bozan O.B., Kwon S.J., Rucker T.R., Thomas C.T., Yokomi R.K., Lee R.F., Folimonova 

S., and Vidalakis G. 

Implication of Toxoptera citricida on temporal and spatial dispersion of Citrus tristeza 

virus in Southern Mexico 

Domínguez Monge S., Mora Aguilera G., Loeza Kuk E., Flores Sánchez J.L., Acevedo 

Sánchez G., and Robles García P. 

Population variation of Citrus tristeza virus 

Qing L., Ruan T., Xiong Y., Zhou Y., Song Z., Sun X.C., Li Z.A., and Zhou C.Y. 

Nucleotide sequence of three genes of Citrus tristeza virus from selected isolates in a 

program of preimmunization 

Zanutto C.A., Muller G.W., Corazza M.J., and Nunes W.M.C. 

A comparative study and vector transmissibility of relevant Citrus tristeza virus (CTV) 

populations from Italy indicates a risk for further epidemics 

Yahiaoui D., Djelouah K., DÓnghia A.M., and Catara A. 

Prevalence and epidemiology of Citrus tristeza virus in Andalucía and Murcia regions 

of Spain 

Gorris M.T., Muñoz C., Cano A., Hermoso de Mendoza A., Martínez M.C., Hermosilla A., 

Fuentes F., Bertolini E., Collado C., López A., and Cambra M. 

Epidemiology of Citrus tristeza virus in experimental nursery blocks of citrus rootstock 

species in Spain 

Gorris M.T., Rodríguez A., Martínez M.C., Bertolini E., Collado C., Botella P., López A., and 

Cambra M. 

Monitoring of Citrus tristeza virus (CTV) and characterization of local isolates in Algeria 

Larbi D., Belkahla H., Djelouah K., and D’Onghia A.M. 

Evaluation of the sampling method of Citrus tristeza virus (CTV) in Apulia Region, Italy 

DÓnghia A.M., Al Naasan Y., Santoro F., Figorito B., and Gualano S. 

Integrated Citrus tristeza virus complex management in Sicily 

Tumminelli R., Rotolo M.C., Saraceno F., Patti M.R., Saitta R., Conti F., Fisicaro R., Cavallaro 

A., Cavallaro G., Cutuli A., Greco G., Di Natale A., Garozzo M., Gullotta S., Privitera S., 

Quattrocchi S., Ricca G., Bertolami E., Calderone G., Maimone F., Schillaci G., Trifiletti 

A., Corno G., Bono G., Federico R., Lo Grasso F., Vicari M., Lo Presti P., Truncali S., Sicilia L., 

Giacalone A., Adragna V., Vecchio S., Filiddani R., Fascetto G.T., Marano G., Spadafora 

A., D’Anna R., Carta Cerella D., and Sinatra V. 

Biological and molecular characterization of a Citrus tristeza virus isolate inducing 

seedling yellows and stem pitting detected in Hunan province, China 

Licciardello G., Russo M., Daden M., Dai S., Xiao C., Deng Z., and Catara A. 

Evaluation of productive and physiological parameters on ‘Tarocco’ orange infected 

by severe isolate of Citrus tristeza virus 

Sorrentino G., Guardo M., Russo M.P., Davino S., and Caruso A. 

Eradicating Citrus tristeza virus and Citrus tatter leaf virus from double infected citrus 

plants 

Qiao Q., and Jiang L. 



S14P19 

S14P20 

S14P21 

S14P22 

S14P23 

S14P24 

S14P25 

S14P26 

S14P27 

S14P28 

S14P29 

S14P30 

S14P31 

S14P32 

S14P33 

S14P34 

S14P35 

Construction of an Infectious cDNA clone of Citrus tatter leaf virus from an infected 

sweet orange 

Song Z., Zhou C.Y., Liu K.H., and Li Z.A. 

The psorosis B syndrome in citrus is associated to a sequence variant of the Citrus 

psorosis virus RNA2 

Velázquez K., Alba L., Pina J.A., Navarro L., Moreno P., and Guerri J. 

Sensitivity to Citrus psorosis virus of species and hybrids of the genus Citrus and relatives 

Velázquez K., Alba L., Zarza O., Vives M.C., Pina J.A., Juárez J., Navarro L., Moreno P., and 

Guerri J. 

Detection and quantitation of Citrus psorosis virus by real time RT-PCR 

Velázquez K., Alba L., Guerri J., Moreno P., Navarro L., and Vives M.C. 

Improvement in diagnosis for Citrus Psorosis in Argentina by qRT-PCR 

De Francesco A., Reyes C.A., Costa N., and Garcia M.L. 

Cloning and sequence analysis of the large coat protein of Satsuma dwarf virus Fengjie 

isolate 

Sun X.C., Qing L., Yang F.Y., and Zhou C.Y. 

Characterization and diffusion of Citrus leaf blotch virus (CLBV) in Southern Italy 

Guardo M., Sorrentino G., and Caruso A. 

Citrus leaf blotch virus (CLBV) invades meristematic regions in Nicotiana benthamiana 

and citrus 

Agüero J., Vives M.C., Velázquez K., Ruiz-Ruiz S., Juárez J., Navarro L., Moreno P., and 

Guerri J. 

Simultaneous detection of Citrus exocortis viroid and Hop stunt viroid in citrus plants by 

direct tissue-print duplex real-time RT-PCR 

Bertolini E., Martínez M.C., Serra P., Olmos A., Carbó C., Duran-Vila N., and Cambra M. 

Setting up and evaluation of new primer sets for the detection of Spiroplasma citri the 

causal agent of Citrus Stubborn disease 

Abdel Fattah A., Valentini F., Frasheri D., D’Onghia A.M., and Djelouah K. 

Biological characterization of a new lemon disease in China 

Chen H.M., Li Z.A., Zhou Y., Wang X.F., Tang K.Z., and Zhou C.Y. 

Virus and virus-like diseases of citrus in Oman 

Al-Sadi A.M., and Al-Harthi S.A. 

Recent trends in diagnosis, characterization and management of major virus and viruslike 

pathogens infecting citrus in India 

Ghosh D.K. 

The citrus nursery tree certification program in Spain 

Pina J.A., Chomé P., Vives M.C., and Navarro L. 

COST FA0806: Plant virus control employing RNA-based vaccines: A novel nontransgenic 

strategy 

Voloudakis A.E. 

Performance of ‘Maltaise’ demi-sanguine sweet orange on eight rootstocks inoculated 

with Citrus exocortis viroid (CEVd) and Cachexia viroid (CVIIb) 

Najar A., Homri N., Bouhlel R., Ben Mimoun M., and Duran-Vila N. 

Biological and molecular detection of Citrus psorosis virus in the Northwest region of 

Morocco 

Achachi A.A., and Ibriz M. 


SESSION 15: Fungal diseases 



Conveners: Dr. Antonio VICENT (Instituto Valenciano Investigaciones Agrarias, Spain) and Dr. Tian 

SCHUTTE (Citrus Research International, South Africa). 

Oral ID Title 

S15O01 The arrival of Citrus Black Spot (Guignardia citricarpa) in Florida and current research 

questions 

Dewdney M.M., Peres N.A., Schubert T.S., Mondal S.N., Hu J., and Hincapie Caputo M. 

S15O02 Predictive model for ascospore release of Guignardia citricarpa using climatological 

data 

Dummel D.M., Agostini J.P., and Moschini R. 

S15O03 Assessment of retention and persistence of copper fungicides on sweet orange fruit 

and leaves using fluorometry and copper residue analyses 

Schutte G.C., Kotze C., Van Zyl J.G., and Fourie P.H. 

S15O04 Phyllosticta species associated with citrus diseases in China 

Wang X.H., Chen G.Q., Huang F., and Li H.Y. 

S15O05 Development of an agrotransformation gene-silencing-system for Phyllosticta citricarpa 

and its use in functional analysis of the pathogenic genes 

Goulin E.H., Petters D.A. L., Figueiredo J.A.G., Senkiv C.C., Silva Jr. G.J., Kava-Cordeiro V., 

Galli-Terasawa L. V., Peña L., and Glienke C. 

S15O06 Epidemiology of Alternaria Brown Spot of mandarins under semi-arid conditions in 

Spain 

Bassimba D.D.M., Mira J.L., and Vicent A. 

S15O07 Spray deposition benchmarks for control of Alternaria Brown Spot and evaluation of 

adjuvants to improve fungicide spray deposition in citrus orchards 

van Zyl J.G., Schutte G.C., and Fourie P.H. 

S15O08 Chemical control of Colletotrichum acutatum and C. gloeosporioides, causal agents 

of Citrus Postbloom Fruit Drop in Brazil 

Goes A., and Rinaldo D. 

S15O09 Pathogenicity and genetic relationship of strains of Elsinoë australis causing Citrus Scab 

disease 

Hyun J.W., Yi P.H., Yun S.H., Hwang R.Y., and Levy L. 

S15O10 Association and interaction of edaphic factors with root disease related citrus decline 

Pretorius M.C., Labuschagne N., Kotze C., and McLeod A. 

S15O11 Searching for citrus rootstocks resistant to Mal Secco disease: a review 

Nigro F., Ippolito A., and Salerno M.G. 


S15P01 

S15P02 

S15P03 

Endophytic actinomycetes for the biological control of Phyllosticta citricarpa 

Glienke C., Savi D.C., Goulin E.H., Kava-Cordeiro V., and Silva Jr G.J. 

Population genetics of Guignardia citricarpa in South Africa 

Carstens E., Linde C.C., Slabber R., Langenhoven S., Schutte G.C., Fourie P.H., and 

McLeod A. 

First report of false melanose symptoms of Citrus Black Spot on sweet orange leaves in 

Brazil 

Silva Jr G.J., Pereira R.G., Marin D.R., Wulff N.A., Scapin M.S., and Sala I. 



S15P04 

S15P05 

S15P06 

S15P07 

S15P08 

S15P09 

S15P10 

S15P11 

S15P12 

S15P13 

S15P14 

S15P15 

S15P16 

S15P17 

S15P18 

S15P19 

S15P20 

S15P21 

S15P22 

S15P23 

Biocontrol of Citrus Black Spot disease: perspectives using fungal endophytes of citrus 

Jung L.F., Goulin E.H., Savi D.C., Schuh R., Galli-Terasawa L.V., Glienke C., and Kava- 

Cordeiro V. 

Modelling of Guignardia pseudothecium maturation and ascospore dispersal in citrus 

orchards 

Fourie P.H., Schutte G.C., Serfontein S., and Swart S.H. 

Infectious period of Citrus Black Spot on sweet orange 

Lourenço S.A., Gasparoto M.C.G., Spósito M.B., Amorim L., and Gottwald T.R. 

Characterization of Guignardia spp. from citrus fruit in Argentina 

Kornowski M.V., and Agostini J.P. 

Integrated approaches to minimize Alternaria Brown Spot of citrus in Italy 

Bella P., Russo M., Tomasello M., Catara A., Catara V., and La Rosa R. 

Varietal resistance and management of Alternaria Brown Spot in Brazil 

Azevedo F.A., Pacheco C.A., Martelli I.B., and Polydoro D.A. 

Outbreak and occurrence of Alternaria Brown Spot in China 

Huang F., and Li H.Y. 

Evolution of symptoms caused by Alternaria alternata on ‘Nova’ mandarin fruit and its 

schematic sequence 

Burdyn L., Garran S.M., and Avanza M.M. 

Commercial-scale Alternaria Brown Spot resistance screening as the first step in 

breeding new mandarins for Australia 

Miles A.K., Newman T.K., Gultzow D.L., Parfitt S.C., Drenth A., and Smith M.W. 

Difference in susceptibility between young and mature ‘Minneola’ tangelo leaves 

Liarzi O., Sela N., and Ezra D. 

Screening for Alternaria Brown Spot resistance in the triploid mandarin breeding 

programme in Spain 

Bassimba D.D.M., Vicent A., Cuenca J., Aleza P., and Navarro L. 

Enhancing of physiological parameters improves resistance against Alternaria Brown 

Spot of mandarins 

Llorens E., Fernandez-Crespo E., Camañes G., Lapeña L., and Garcia-Agustin P. 

Strobilurin resistance of Alternaria alternata, the causal agent of Alternaria Brown Spot, 

in Florida tangerine hybrid groves 

Vega B., and Dewdney M.M. 

Evaluation of fungicide mixtures as replacement for carbendazim for Citrus Postbloom 

Fruit Drop control in Brazil 

Silva Jr G.J., Spósito M.B., Marin D.R.,and Amorim L. 

Survival of Colletotrichum acutatum in citrus leaves 

Pereira W.V., Tanaka F.A.O., Rodrigues M.B.C., and Massola Junior N.S. 

Pollen exudate stimulates conidial germination of Colletotrichum acutatum 

Gasparoto M.C.G., Lourenço S.A., Marques J.P.R., Appezzato-da-Glória B., and Amorim L. 

Fungal diseases of citrus in Panama 

Aguilera-Cogley V., and Vicent A. 

Epidemiology and control of Citrus Greasy Spot in Panama 

Aguilera-Cogley V., and Vicent A. 

Biological control of Citrus Canker and Melanose using rhizobacteria in Korea 

Ko Y.J., Kang S.Y., and Jeun Y.C. 

Expression profiles of differentially regulated genes of citrus during infection by Elsinoë 

fawcettii 

Hyun J.W., Yi P.H., and Kim Y.J. 



S15P24 

S15P25 

S15P26 

S15P27 

S15P28 

S15P29 

S15P30 

S15P31 

Biological control of Phytophthora sp. and Fusarium sp. in citrus nurseries in Egypt 

Ahmed Y., Ippolito A., El-Shimy H., D’onghia A.M., and Yaseen T. 

Dry Root Rot, an alliance between Fusarium solani and Phytophthora or other factors 

against citrus in California 

Adesemoye A.O., and Eskalen A. 

Efficacy of water soluble silicon in managing Fusarium Dry Root Rot of citrus 

Marais L.J. 

Application of artificial intelligence to the visual diagnosis of quarantine citrus diseases 

Burdyn L., Garran S.M., Stegmayer G., and Milone D.H. 

Optimization of copper application schedules for foliar citrus disease management 

based on fruit growth, historical rainfall patterns and copper residue decay 

Zortea T., Fraisse C.W., and Dewdney M.M. 

Phytosanitary situation of Chilean citrus industry 

Besoain X., Castro M., Camps R., and López E. 

Storage technology for conservation of seeds of citrus rootstocks 

Nascimento L.M., Moreira J., Brito M.C.R., Brito P.C.N., and Sanches J.M. 

Morphological and molecular diversity of Phytophthora nicotianae strains isolated 

from citrus plantations in Cuba 

Llauger R., Coto O., Peña M., Zamora V., and Collazo C. 

SESSION 16: Entomology and pest control 



Conveners: Dr. Alberto URBANEJA (Instituto Valenciano Investigaciones Agrarias, Spain), Dr. Josep A. 

JACAS (Universitat Jaume I, Spain), Dr. Phil A. STANSLY (University of Florida, USA) and Dr. Jorge E. PEÑA 

(University of Florida, USA). 

Oral ID Title 

S16O01 

S16O02 

S16O03 

S16O04 

S16O05 

S16O06 

S16O07 

S16O08 

The status of citrus IPM in California 

Grafton-Cardwell E. E. 

The status of citrus IPM in South Africa 

Grout T.G. 

IPM in Spanish citrus: current status of Biological Control 

Urbaneja A., Tena A., and Jacas J.A. 

Status of citrus IPM in the southern Mediterranean Basin 

Mazih A. 

Integrated and disease management in New Zealand. Progress, changes and 

challenges since 2004 

Pyle K.R., and Jamieson L.E. 

Progress toward integrated management of Asian Citrus Psyllid in Florida 

Stansly P.A. 

Perspective of the Indonesian citriculture in the presence of Huanglongbing disease 

Supriyanto A.S., and Nurhadi N. 

Non-target effects of cultural practices to manage the bacterial disease HLB on soil 

food webs that affect the insect pest Diaprepes abreviatus 

Campos-Herrera R., El-Borai F.E., Schumann A., and Duncan L.W. 


Oral ID Title 

S16O09 

S16O10 

S16O11 

S16O12 

S16O13 

S16O14 

S16O15 

S16O16 

S16O17 

S16O18 

S16O19 

S16O20 


S16P01 

S16P02 

S16P03 

S16P04 

S16P05 

Protection of young trees from HLB through disruption of Diaphorina citri (Kuwayama) 

feeding behavior 

Rogers M.E., Ebert T.A., Kim K.D., and Weaver C.E. 

Effect of UV-blocking plastic films on plant location and spread of the Asian Citrus 

Psyllid (ACP), Diaphorina citri Kuwayama (Hemiptera: Psyllidae) on citrus 

Miranda M.P., Marques R.N., Santos F.L., Felippe M.R., Moreno A., and Fereres A. 

Ontogenic variation in citrus flush shoots and its relation with host plant finding and 

acceptance by Asian Citrus Psyllid (Hemiptera: Psyllidae) 

Setamou M., and Patt J. M. 

Targeting juvenile hormone metabolic genes in the Asian Citrus Psyllid (Diaphorina citri) 

as a strategy to reduce the spread of Citrus Greening disease 

Van Ekert E., Borovsky D., Powell C.A., Cave R.D., Alessandro R.T., and Shatters R.G. 

Biological Control of red scale on citrus on the central coast of New South Wales 

Dao H.T., Beattie G.A.C., Holford P., Spooner-Hart R., Meats A., and Burgess L. 

Sugar subsidies improve the fitness and efficacy of the parasitoid Aphytis melinus in the 

field 

Tena A., Cano D., Pekas A., Wäckers F., and Urbaneja A. 

Ground cover management in citrus affects the Biological Control of aphids 

Gómez-Marco F., Tena A., Jacas J.A., and Urbaneja A. 

Field evaluation of some pesticides and biological control against citrus mealybug 

Planococcus citri Risso (Hemiptera: Pseudococcidae) 

Kararacoglu M., Kutuk H., Tufekli M., Satar G., and Yarpuzlu F. 

Can imidacloprid cause lepidopteran pest repercussions? 

Moore S.D., Van der Walt R., Kirkman W., and Du Preez D. 

Ecology and management of Kelly’s citrus thrips in eastern Spain 

Navarro-Campos C., Pekas A. , Aguilar A., and Garcia-Marí F. 

Monitoring and management of Brevipalpus chilensis Baker (Acarina: Tenuipalpidae) 

in citrus 

Olivares N., Vargas R., and Ripa R. 

Host adaptation of Tetranychus urticae populations in clementine orchards with a 

Festuca arundinacea cover may contribute to its natural control 

Aguilar-Fenollosa E., Pina T., Gómez-Martínez M.A., Hurtado M.A., and Jacas J.A. 

Analysis of population trends of citrus pests from an area-wide field survey and 

monitoring network established in eastern Spain 

Garcia-Mari F. 

Arthropod pest composition and farmers perceptions of pest and disease problems 

on citrus in Kenya 

Ekesi S. 

Thresholds for HLB vector control in infected commercial citrus and compatibility with 

Biological Control 

Monzó C., Stansly P.A., and Urbaneja A. 

Development of the Huaglongbing (HLB) vector, Diaphorina citri Kuwayama, 1908 

(Hemiptera: Psyllidae), in different host plants 

Alves G.R., Diniz A.J.F., Lima A.A., Vieira J.M., and Parra J.R.P. 

Agreggation and sampling plans for Diaphorina citri (Hemiptera: Psyllidae) immatures 

in citrus 

Asplanato G., Amuedo S., and Franco J. 



S16P06 

S16P07 

S16P08 

S16P09 

S16P10 

S16P11 

S16P12 

S16P13 

S16P14 

S16P15 

S16P16 

S16P17 

S16P18 

S16P19 

S16P20 

S16P21 

Use of oils to control the Asian Citrus Psyllid (Diaphorina citri) in Mexican lime under dry 

tropic conditions in Mexico 

Orozco-Santos M., Velázquez-Monreal J.J., García-Mariscal K., Manzanilla-Ramírez 

M.A., Carrillo-Medrano S.H., and Robles-González M.M. 

Seasonal patterns in the proportion of Asian Citrus Psyllid (Diaphorina citri) carrying 

Candidatus Liberibacter asiaticus 

Ebert T.A., Brlansky R.H., and Rogers M.E. 

Effect of Imidacloprid (Winner) on trunk application to psyllid (Diaphorina citri – 

Hemiptera: Psyllidae) control on citrus 

Lozano Leonel Jr F., Soares R.D.J., and Moraes J.P. 

Movement of Asian Citrus Psyllids in HLB-affected and healthy citrus trees 

Cen Y., Wu F., Liang G., Chen J., Deng X., and Xia Y. 

Effectivity of Huanglongbing vector (Diaphorina citri kuw.) control citrus grower group 

based in regency of Sambas, West Kalimantan, Indonesia 

Supriyanto A.S., Nurhadi N., Zuhran Z., and Purbiati P. 

Behavioural responses of Diaphorina citri to host plant volatiles 

Fancelli M., Birkett M.A., Pickett J.A., Moraes M.C.B., Laumann R.A., and Borges M. 

Efficacy of selected insecticides for the control of the California Red Scale in Southern 

Italy 

Campolo O., Grande S.B., Chiera E., and Palmeri V. 

Altea (Eastern Spain) area-wide project to control California Red Scale Aonidiella 

aurantii (Hemiptera: Diaspididae) based on conservation and release Biological 

Control agents 

Laborda R., Garcia-Mari F., Sanchez A., Xamani P., Garcia A., Punset C., Bernabeu P., 

Aznar M., and Bertomeu S. 

Hyperparasitism may prevent efficient regulation of Aphis spiraecola Patch. 

(Homoptera: Aphididae) in citrus orchards by primary parasitoids 

Gómez-Marco F., Tena, A., Jacas, J.A., and Urbaneja, A. 

Citrus mealybug biological control strategies and large scale implementation on citrus 

in Turkey 

Erkilic L.B., Demirbas H., and Guven B. 

Repellency and acceptability of several substances by ant species in citrus groves in 

Spain 

Campos Rivela J.M., Martínez-Ferrer M.T., Fibla J.M. , and Pla M. 

Taxonomic studies for classical Biological Control of Delottococcus aberiae (Hemiptera: 

Pseudococcidae) 

Beltrà A., Navarro-Campos C., Garcia-Marí F., Malausa T., Giliomee J.H., Addison P., and 

Soto A. 

Canibalism and intraguild predation in citrus mealybug natural enemies 

Gkounti V.T., Savvopoulou-Soultani M., Kontodimas D.C., and Milonas P.G. 

Biological Control of the citrus mealybug: dispersion pattern of the parasitoid Anagyrus 

sp. near pseudococci, during augmentative releases 

Franco J.C. , Zina V., Silva E.B. , Steinberg S., Belda J.E. , Branco M., Suma P., and Mendel Z. 

Study on Biological Control and trap techniques of Thrips flavidulus (Thysanoptera: 

Thripidae) in citrus orchards 

Yao H., Yu F., and Zhang H. 

Thysnoptera occurring in clementine mandarin under three ground cover management 

strategies: species composition, abundance and distribution 

Aguilar-Fenollosa E., and Jacas J.A. 



S16P22. 

S16P23 

S16P24 

S16P25 

S16P26 

S16P27 

S16P28 

S16P29 

S16P30 

S16P31 

S16P32 

S16P33 

S16P34 

S16P35 

S16P36 

S16P37 

S16P38 

S16P39 

Effect of biotic and abiotic factors on the insurgence of fruit scars in Italian orange 

orchards 

Siscaro G., Zappalà L., Biondi A., Conti F., and Fisicaro R 

Thrips population dynamics, composition and first survey on ground-dwelling predatory 

mites in lemon orchards in Italy 

Biondi A., Zappalà L., Tropea Garzia G., Perrotta G., and Siscaro G. 

Pollen availability in the cover crop may affect the biological control of Tetranychus 

urticae in citrus 

Pina T., Argolo P. S., Urbaneja A.,and Jacas J. A. 

Assessment of trophic interactions among citrus mites by DNA-based gut content 

analysis 

Pérez-Sayas C., Pina T., Gómez-Martínez M.A., Jacas J.A., and Hurtado M.A. 

Effectiveness and economics of a novel proactive approach for managing the Citrus 

Rust Mite in Texas 

Setamou M., and Sekula D. 

Spider mite response in citrus rootstocks is mediated by the oxylipin pathway 

Agut B., Hurtado M.A., Jacas J.A., and Flors V. 

Impact of three ant species on pest populations in Mediterranean citrus orchards 

Calabuig A., Pekas A., and García Marí F. 

Ant nests distribution in citrus groves under different ground cover management 

strategies in Spain 

Martinez-Ferrer M. T., Campos Rivela J. M., Fibla J. M., Pla M. 

Composition and flying activity of Coleoptera staphylinids in citrus orchards 

Adorno A., Biondi A., Zappalà L., Siscaro G., and Sabella G 

Entomo-pathogenic nematodes to combat -infestations at Ticofrut 

Camacho H., Yglesias G., and Faerron P. 

Monitoring and Management of Naupactus (= Asynonychus) cervinus in citrus 

orchards in Chile 

Luppichini P., and Olivares N. 

Population dynamic of citrus blackfly in Tahiti lime in the state of São Paulo, Brazil 

Felippe N, and Raga A. 

Integrated strategies to monitor and control Citrus Flower Moth, Prays citri Mill. 

(Lepidoptera: Yponomeutidae) on nursery trees of the Mediterranean área 

Conti F., and Fisicaro R. 

Biology of Citrus Fruit Borer, Citripestis sagittiferella Moore and its control 

Srijuntra S., Manusmunkong B., Sahaya S., Jumroenma K., and Srikachar S. 

Spirotetramat (Movento®): a new tool for Aonidiella aurantii Maskell management in 

Spain 

Izquierdo J., and Fullana J. 

Carbendazim, mancozeb and pyraclostrobin residues resulting from the chemical 

control of Citrus Black Spot (Guignardia citricarpa) on Valencia orange in the Northeast 

of Argentina 

Waskowicz C., Sosa A., Becerra V., Navarro R., Burdyn L., Garran S.M., and Mousqués J. 

Evaluation of a novel insecticide, DPX-HGW86 10% OD (Benevia) and DPX-HGW86 

20% SC (Verimark), for Diaphorina citri (Hemiptera: Psyllidae) control 

Miranda M.P., Felippe M.R., Garcia R.B, Caldeira R.E., and Noronha Jr N.C. 

The effect of foliar application of insecticides pyrethroids and neonicotinoids on the 

population of Panonychus citri (McGregor, 1916) (Acari: Tetranychidae) in laboratory 

Zanardi O.Z., Rugno G.R., Bordini G.P., Beloti V.H., and Yamamoto P.T. 



S16P40 

S16P41 

S16P42 

S16P43 

S16P44 

S16P45 

S16P46 

S16P47 

SESSION 17: Varieties 

Side effects of some pesticides under laboratory conditions on important parasitoids 

and predators in citrus ecosystem 

Simsek V.M., Uygun N., and Satar S. 

Side effects of some pesticides under laboratory conditions on important parasitoids 

and predators in citrus ecosystem 

Simsek V.M., Uygun N., and Satar S. 

New book on citrus pests: citrus pests. Integrated pest management in countries of 

Mediterranean climate (Plagas de los cítricos. Gestión integrada en países de clima 

mediterráneo) 


Impact of pesticides used in citrus orchards on the beneficial insects Cryptolaemus 

montrouzieri Mulsant 

Rahmouni R., and Chermiti B. 

Preliminary survey of the Green Lacewings (Neuroptera, Chrysopidae) in citrus orchards 

in Northern east of Tunisia (Cap Bon) 

Limem S. E., and Chermiti B. 

Mating disruption technique as a control method for California Red Scale: a review of 

doses, efficacy and date of application. 

Navarro-Llopis, V., Alfaro C., Vacas S., Primo Millo, J. 

Physiological selectivity of insecticides used for control of Diaphorina citri (Kuwayama, 

1908) on larvae of Ceraeochrysa cubana (Hagen, 1861) 

Rugno G., Zanardi, Beloti, Cunha, Barbosa, Parra, and Yamamoto 

Distribution of the Asian Citrus Psyllid, Diaphorina citri (Hemiptera: Psyllidae) in Iran 

Parsi F., Manzari S., Askari M., Amin G., Ranjbar S., and Naseri M. 

Oral presentations at Auditorium 1, on Monday 19 th from 15:15 to 17:15 


Conveners: Dr. Pablo ALEZA (Instituto Valenciano Investigaciones Agrarias, Spain) and Dr. Giuseppe 

REFORGIATO RECUPERO (Centro di Ricerca per l’Agrumicoltura, Italy). 

Oral ID Title 

S17O01 

S17O02 

S17O03 

S17O04 

S17O05 

S17O06 

New citrus variety evaluation in Australia 2005-2012 

Sanderson G., Creek A., Lacey K., and Wallace M. 

‘Sweet Sicily’ and ‘Early Sicily’, two new triploids from the program of CRA-ACM, Centro 

di- Ricerca per lAgrumicoltura e le Colture Mediterranee, Acireale, Italy 

Russo G, Reforgiato Recupero G, Recupero S, and Pietro Paolo D. 

Comparison of performance of different late-maturing navel selections around the 

world 

Rabe E., Turner P., and Chavarria J. 

Three new varieties of clementine: ‘Clemenverd’, ‘Nero’ and ‘Iviaman1957’ 

López-García A., Terol J., Tadeo F.R., Herrero A., Ibáñez V., and Talón M. 

Relationship between sensory and physic-chemical quality parameters of ‘Lanelate’ 

with protected geographical indication 

Duarte A., Mendes S., Nunes S., Sustelo V., and Gomes C. 

New promising citrus hybrids for the ornamental use 

Recupero S., Russo G., and Reforgiato Recupero G. 


Oral ID Title 

S17O07 

S17P08 


S17P01 

S17P02 

S17P03 

S17P04 

S17P05 

S17P06 

S17P07 

S17P08 

S17P09 

S17P10 

S17P11 

S17P12 

S17P13 

S17P14 

S17P15 

S17P16 

‘Meirav Seedless’, a new promising Israeli mandarin: effects of rootstocks and growth 

regulators on yield and fruit quality 

Kanonich Y.K., Holsman S.H., Oren Y.O., Kaplan I., Tagari E., Fainzack M., and Giladi B. 

How many seeds are acceptable in commercial citrus varieties derived from irradiation? 

Williams T. E. 

Plant growth, initial fruit production and yield efficiency of twelve early maturing sweet 

orange cultivars in São Paulo State, Brazil 

Caputo M.M., Mourão Filho F.A.A., Silva S.R, Stuchi E.S., and Bremer Neto H. 

Initial production of 17 mid-season sweet orange cultivars in Southwestern São Paulo 

State, Brazil 

Ramos Y. C., Mourão Filho F. A. A., Stuchi E. S., Silva S. R., Caputo M. M., Bremer Neto H., 

and Fadel A. L. 

Determination of yield and fruit quality characteristics of several local and foreign 

originated nucellar orange clones in Adana province of Turkey 

Polatöz S., and Tuzcu Ö. 

Yield and fruit quality of two early maturing orange cultivars, Navelina and Fukumoto, 

in Andalusia (Spain) 

Merino C., Hervalejo A., Salguero A., and Arenas Arenas F.J. 

Phenological growth stages of oranges and mandarines in Entre Ríos province 

(Argentina) 

Rivadeneira M. F. 

Fruit characteristics of some late maturing commercial mandarin cultivars in Spain 

Simón-Grao S., Simón I., Lidón V, Nieves M., Carbonel A.A., Manera J., Hernandez F., and 

Garcia-Sanchez F. 

Evaluations of early satsuma selections for California. 

Kahn T., and Siebert T. 

Yield and fruit quality of two satsuma cultivars, Okitsu and Iwasaki, in Andalusia (Spain) 

in 2010/11 season 


Behaviour of Parana grapefruit in the Southeastern region of Paraguay 

Wlosek Stañgret C.R., and Canteros B.I. 

Characterization of grapefruit varieties produced in Argentina and Paraguay 

Sgroppo S.C., Pereyra M.V., Wlosek Stañgret C.R., and Canteros B.I. 

Evaluation of lemon selections for the deserts of the United States 

Wright G.C., and Kahn T. 

Selection and field evaluation of three new cultivars of lemon in the South-east of Spain 

Porras I., Pérez-Pérez J. G., García-Lidón A., Sánchez-Baños M., and Pérez-Tornero O. 

Preselection of promising triploid mandarin varieties in Corsica 

Bouffin J., Froelicher Y., Luro F., and Ollitrault P. 

Two new IVIA triploid hybrids of mandarin; IVIA-592 and IVIA-599 

Cuenca J., Aleza P., Juarez J., Pina J.A., and Navarro L. 

Selection of new Ponkan like mandarins 

Bastianel M., Cristofani-Yaly M., Schinor E.H., Simonetti L.M., Manente K.K.M., De Negri 

J.D., Azevedo F.A., and Machado M.A. 

New tangors for Brazilian citriculture 

Schinor E.H., Pacheco C.A., Bastianel M., Azevedo F.A., and Cristofani-Yaly M. 



S17P17 

S17P18 

S17P19 

S17P20 

S17P21 

S17P22 

S17P23 

S17P24 

S17P25 

S17P26 

S17P27 

S17P28 

S17P29 

S17P30 

Three new easy peeler varieties bred by the agricultural research council released 

world wise. 

van Rensburg P.J., Sippel A.D., Combrink N.K., Maritz J.G.J, and Bijzet Z. 

A new potential elite citrus hybrid 

Cheng C.F., Wei Z.X., Hong L., Wu C.Q., and Qi J.R. 

Acceptability of Fremont mandarin in Brazil: a variety with agronomic performance 

and resistance to Alternaria Brown Spot 

Pacheco C.A., Schinor E.H., Moretti M.R., Bastianel M., Machado M.A., and Azevedo F.A. 

Scion and rootstock combinations for ornamental citrus in containers 

Fadini M., Girardi E.A., Santos M.G., Gesteira A.S., Passos O.S., Souza F.V.D., and Soares 

Filho W.S. 

Current situation of the Chilean citrus industry 

Castro M., Besoain X., Herrera V., and Cautin R. 

Influence of gamma irradiation on seedless citrus production: pollen germination and 

fruit quality 

Bermejo A., Pardo J., and Zaragoza S. 

Identification of new volatile compounds in citrus hybrid mandarinquat Indio (Citrus 

japonica Thunb. sp. × Citrus reticulata Blanco) 

Delort E., Decorzant E., Casilli A., and Jaquier A. 

Molecular characterization of Tahiti lime selections by RAPD analysis 

Bremer Neto H., Mourão Filho F.A.A.M.F., Stuchi E.S.S., Soriano L.S., Miyata L.M., and 

Camargo L.E.A.C. 

A natural mutant cultivar Zigui shatian pummelo (Citrus grandis (L.) Osbeck) showing 

self-sterility due to abnormal post-zygotic embryo development and not to selfincompatibility 

Chai L.J., Ge X.X., Biswas M.K., Xu Q., and Deng X.X. 

Relation between temperature and the colour coordinate a during the development 

of the external colour of lemon fruits 

Conesa A., Manera J., Brotons J., and Porras I. 

Determination of the geographical origin of navel orange by near infrared spectroscopy 

Su X.S., Zhang X.Y., Jiao B.N., and Cao W.Q. 

A new lemon genotype for ornamental use obtained by gamma irradiation 

Uzun A., Gulsen O., Kafa G., and Seday U. 

New mandarin triploid hybrids Aya and Hana selected in Morocco 

Handaji N., Benyahia H., Benaouda H., Arsalane N., and Srairi I. 

Mutation breeding for seedless cultivars in Argentina 

Garavello M., Anderson C., Prina A., and Martinez A. 


SESSION 18: Rootstocks 

Oral presentations at Auditorium 2, on Tuesday 20 th from 10:30 to 13:30 


Conveners: Dr. María A. FORNER (Instituto Valenciano Investigaciones Agrarias, Spain) and Dr. William 

S. CASTLE (Citrus Research and Education Center, USA) 

Oral ID Title 

S18O01 

S18O02 

S18O03 

S18O04 

S18O05 

S18O06 

S18O07 

S18O08 

S18O09 

S18O10 


S18P01 

S18P02 

S18P03 

S18P04 

S18P05 

Reflections on a career in citrus rootstock evaluation and commercialization 

Castle W.S. 

Citrus rootstocks in Morocco: present situation and future prospects 

El Guilli M., Belmahdi I., and Zemzami M. 

Seven hybrid citrus rootstocks released by USDA: comparison of characteristics and 

use 


The evaluation of Chinese rootstock for tree growth, yield and quality of ‘Lane Late’ 

oranges grown in Australia 

Khurshid T., Sanderson G., and Donovan N. 

Dwarfing rootstocks for ‘Valencia’ sweet orange 

Ramos Y.C., Stuchi E.S., Girardi E.A., Leão H.C. , Gesteira A.S., Passos O.S., and Soares 

Filho W.S. 

The development of improved tetraploid citrus rootstocks to facilitate advanced 

production systems and sustainable citriculture in Florida 

Grosser J.W., Barthe G.A., Gmitter Jr. F.G., and Castle W.S. 

Citrus macrophylla rootstock improves the performance of ‘Mexican’ lime trees on 

citrus interstocks in calcareous soils 

Medina-Urrutia V.M., Robles-González M.M., Virgen-Calleros G., and Manzanilla-Ramírez 

M.A. 

Performance of ‘Valencia Late’ orange on 14 rootstocks in the Gharb region in Morocco 

Benyahia H., Benazzouz A., Talha A., Beniken L., Omari F.E., Handaji N., Jacquemend E., 

and Srairi I. 

Results from a three years field trial planted at Concordia, Argentina using transgenic 

rootstocks potentially resistent to Citrus Tristeza 

Anderson C., Plata M.I., Garavello M., Costa N., and Peña L. 

‘Forner-Alcaide 5’: a citrus rootstock released in Spain 

Forner-Giner M.A., and Forner J.B. 

Rootstocks affect fruit yield and some fruit quality traits of ‘Star Ruby’ grapefruit in 

Adana (Turkey) 

Yeşiloğlu T., Incesu M., Yılmaz B., Çimen B., and Tuzcu Ö. 

Rootstock effects on photosynthetic performance of young ‘Valencia’ orange trees 

Yeşiloğlu T., Çimen B., İncesu M., and Yılmaz B. 

Effect of the rootstock on some agronomic traits of ‘Nules’ and ‘Nour’ clementines in 

the Souss valey in south Morocco 

Benyahia H., Benazzouz A., Beniken L., Handaji N., Kabbaj T., Essajid A., Chahidi B., 

Jacquemend E., and Srairi I. 

Behavior of ‘Navelina ISA 315’ on 15 rootstocks in Metaponto area, Basilicata, Italy 

Mennone C., Ippolito A., and Reforgiato Recupero G. 

Influence of rootstock on the characteristics of clementine in the plain of Sibari (italy) 

Russo G., Reforgiato Recupero G., Recupero S., Pietro Paolo D., Di Leo A., and Filippelli S. 



S18P06 

S18P07 

S18P08 

S18P09 

S18P10 

S18P11 

S18P12 

S18P13 

S18P14 

S18P15 

S18P16 

S18P17 

S18P18 

S18P19 

S18P20 

S18P21 

S18P22 

S18P23 

S18P24 

Is there a relationship between ferric-chelate reductase activity in roots of Poncirus 

trifoliata and leaf chlorophyll contents? 

Correia P.J., Lopes D., Duarte A., Gama F., Saavedra T., and Pestana M. 

Influence of six citrus rootstocks on fruit quality of ‘Lane Late’ 

Hervalejo A. , Cardeñosa V., Forner-Giner M.A., Salguero A., Pradas I., Moreno J.M., and 

Arenas Arenas F.J. 

Agronomic performance of citrus rootstocks ‘F-A 5’, ‘F-A 13’ and ‘F-A 418’ on ‘Nules’ 

clementine and ‘Navelate’ orange in northeastern Spain 

Fibla J.M., Pastor J., Martinez-Ferrer M.T., Campos Rivela J.M., Forner-Giner M.A., and 

Forner J.B. 

New rootstocks for the high density plantings in citrus 

Bordas M., Torrents J., and Forner-Giner M.A. 

Performance of twelve rootstocks grafted on ‘Nules’ clementine in ANECOOP 

del Pino A., Martínez M., and Forner-Giner M.A. 

Influence of rootstock hydraulic conductance in the response to water stress and its 

relationship to aquaporin expression in citrus 

Rodríguez-Gamir J., Ancillo G., Bordas M., Primo-Millo E., and Forner-Giner M.A. 

Micropropagation for evaluation of new citrus somatic hybrid rootstocks 

Bordas M., Torrents J., and Navarro L. 

Performance of ‘Forner-Alcaide 5’ and ‘Forner-Alcaide 517’ with ‘Loretina’ clementine 

Molina-Nadal M.D., De Miguel A., Valero J.L.., Ripoll F., and Forner-Giner M.A. 

Performance of three rootstocks with ‘Clemenrubi’ and ‘Orogros’ clementines cultivated 

under screen 

Molina-Nadal M.D., De Miguel A., Bonafé C., Valero J.L., Ripoll F., and Forner-Giner M.A. 

Rootstock influence on the incidence of fruit splitting in navel oranges 

Mesejo C., Reig C., Martínez-Fuentes A., and Agustí M. 

Rootstocks for ‘Lane Late’ orange in Valencia 

del Pino A., Martínez M., and Forner-Giner M.A. 

Citrus rootstock trials on calcareous soils in California 

Roose M.L., Kupper R.S., and Federici C.T. 

Potential of ‘Tahiti’ acid lime and ‘Flame’ grapefruit in the Brazilian semiarid 

Bastos D.C., Passos O.S., Nascimento F.S.S., and Nascimento S.S. 

Selection of new citrandarins for citrus rootstocks 

Cristofani-Yaly M., Schinor E.H., Bastianel M., Nascimento A.L., Stuchi E.S., and Machado 

M.A. 

Initial production of ‘Valencia’ sweet orange on 40 rootstocks in Northern São Paulo 

state, Brazil 

Fadel A.L, Mourão Filho F.A.A, Stuchi E.S, and Ramos Y.C. 

Crop production of ‘Okitsu’ satsuma mandarin on nine rootstocks in Southern Brazil 

Tazima Z.H., Neves C.S.V.J., Yada I. F.U., and Leite Junior R.P. 

Effect of rootstock on yield of ‘Okitsu’ satsuma mandarin on sandy soils in Southern Brazil 

Tazima Z.H., Neves, C.S.V.J., Yada I.F.U., Stenzel N.M.C., and Leite Junior R.P. 

Scion rooting and its discriminance in ‘Shiranuhi’ mandarin hybrid in plastic film house 

in Korea 

Moon Y.E., Kang S.B., Kim Y.H., and Han S.G. 

Effects of scion root on flowering, fruit quality and yield of ‘Shiranuhi’ mandarin hybrid 

in plastic film house in korea 

Moon Y.E., Kang S.B., Han S.G., Ko S.W., Chae C.W., Lee D.H., and Choi Y.H. 



S18P25 

S18P26 

S18P27 

S18P28 

S18P29 

S18P30 

Evaluation on drought resistance traits of citrus rootstock seedlings based on multivariate 

statistics 

Xu X.B., Yang Y.L., Gu Q.Q., Huang C.H., and Qu X.Y. 

Performance of three sweet orange varieties grafted on different rootstocks 

Yan S.T., Cheng C.Z., Ma Y.Y., Wang X., and Zhong G.Y. 

Effects of six rootstocks on tree growth, fruit quality and N, P, K content of lemon 

Hong L, and Xie Y.H. 

Tree performance and fruit quality evaluation of ‘Shatangju’ mandarin grafted on four 

rootstocks in South China 

Liu X., Huang M., Li J., Che J., and He Y. 

Influence of different rootstock type on chlorophyll content and mineral elements 

concentration in scion of ‘Kinnow’ mandarin 

Hosseini Farahi M., Aboutalebi Jahromi A., and Hasanzada H. 

Preliminary studies on high density planting of some citrus cultivars to obtain a more 

rapid recovery of investment capital 

Bassal M.A. 

SESSION 20: Citrus and Health 



Conveners: Dr. Francisco TOMÁS-BARBERÁN (Centro de Edafología y Biología aplicada del Segura 

del CSIC, Spain) and Dr. Christine MORAND (Institut National de la Recherche Agronomique, France). 

Oral ID Title 

S20O01 

S20O02 

S20O03 

S20O04 

S20O05 

S20O06 

S20O07 

Flavanones are involved in the cardiovascular protective effects of citrus fruits 

Morand C. 

Health benefits of citrus: recent advances and future outlook 

Patil B.S., Jayaprakasha G.K., and Uckoo R.M. 

Orange and grapefruit bioactive compounds, citrus consumption and health benefits 

Cancalon P., and King D. 

Effects of a long-term grapefruit juice consumption on vascular protection and bone 

metabolism: a controlled randomized cross-over study in post-menopausal women to 

determine the specific role of naringin 

Habauzit V., Verny M., Milenkovic D., Pickering G., Duale C., Bayle D., Thien S., Rambeau 

M., Mazur A., Horcajada M., Dubray C., and Morand C. 

Effect of technological treatments on the bioavailability of flavanones from orange 

Vallejo F., Tomás-Navarro M., Carbonell J.V., Navarro J.L., and Tomás-Barberán F.A. 

Evaluation of the anticancer activity on prostate cancer by low molecular weight 

citrus pectin 

Lu S., Chen J., Yin Y., Xia Q., Zhang J., and Yang Y. 

A molecular approach to characterize the accumulation of ascorbic acid in citrus 

fruits 

Alós E., Legaz P., Rodrigo M.J., and Zacarías L. 



S20P01 

S20P02 

S20P03 

S20P04 

S20P05 

S20P06 

S20P07 

S20P08 

S20P09 

S20P10 

Protective effect of grapefruit naringin on atherosclerosis development and 

identification of the underlying mechanisms 

Milenkovic D., Chanet A., Habauzit V., Bennetau-Pelissero C., Berard Am., Mazur A., and 

Morand C. 

Effect of membrane processing on the radical scavenging activity of juice from IGP 

product Citrus limon from Rocca imperiale (South Italy) 

Loizzo M.R., Tundis R., Bonesi M., Pugliese A., Di Sanzo G., Balducchi R., Verardi A., and 

Calabro V. 

The effect of time and refrigeration on bioavailability of flavanones in healthy volunteers 

after fresh squeezed orange juice consumption 

Tomas-Navarro M., Vallejo F., and Tomás-Barberán F.A. 

The leaves of Mediterranean mandarin could be used as an important source of 

hesperidin, nobiletin and tangeretin 

Durand M.V.S., Fanciullino A-L., Jay-Allemand C., Ollitrault P., Froelicher Y., and Bidel L.P.R. 

Comparative study of fruit flavonoids in ten citrus hybrids 

Ran Y., Zhao Q.Y., Su X.S., Chen W.J., Jiang D., and Jiao B.N. 

Over-consumption of satsuma mandarins is associated with Shang Huo reaction: results 

from case-control studies 

Ma Z.C., and Deng X.X. 

Dissipation curves of cypermethrin in whole fruit and mandarin pulp in Argentina 

Kulczycki Waskowicz C., Sosa A., Beldoménico H., García S., and Repetti M.R. 

Dissipation and residue of forchlorfenuron in citrus fruits 

Chen W.J., Su X.S., Zhao Q.Y., and Jiao B.N. 

Dissipation and residue of 2,4-D in citrus fruits 

Chen W.J., Su X.S., Zhao Q.Y., and Jiao B.N. 

Effect of pesticide spray volumes and doses on the production of marketable lemons 

in Tucumán, Argentina 

Salas López H., Mansilla C., Figueroa D., Carrizo B., Rojas A., Campos A., and Goane L. 

SESSION 21: Postharvest and juice processing technology 

Oral presentations at Auditorium 3, on Monday 19 th from 12:00 to 13:30 


Conveners: Dr. Alejandra SALVADOR (Instituto Valenciano Investigaciones Agrarias, Spain) and Dr. 

Paolo RAPISARDA (Centro di Ricerca per l’Agumicultura e le Colture Mediterranee, CRA-ACM, Italy) 

Oral ID Title 

S21O01 

S21O02 

S21O03 

S21O04 

Biochemical and molecular mechanisms involved in mandarin flavor deterioration 

after harvest 

Tietel Z., and Porat R. 

Traceability of citrus fruit using isotopic and chemical markers 

Fabroni S., Amenta M., and Rapisarda P. 

Fluctuation of limonin and nomilin content in different tissues during fruit development 

of three sweet orange varieties 

Wu H., Tan A., Wang H., Ma Y., Sun Z., Huang X., and Guo L. 

Post-harvest management of citrus fruit in South Asian countries 

Ladaniya M. 


Oral ID Title 

S21O05 

S21O06 


S21P01 

S21P02 

S21P03 

S21P04 

S21P05 

S21P06 

S21P07 

S21P08 

S21P09 

S21P10 

S21P11 

S21P12 

S21P13 

S21P14 

S21P15 

A technological platform for the valorization and recovery of outsize and defective 

PGI citrus fruits from South Italy 

Mazzuca S., Spadafora A., Serra I.A., Bernardo L., Balducchi R., Di Sanzo G., Maccioni O., 

Verardi A., and Calabro V. 

Industrial orange juice (var. ‘Salustiana’) debittering: effects on sensory properties 

Fernández-Vázquez R., Stinco C.M., Hernanz D., Heredia F.J., and Vicario I.M. 

Anthocyanins in citrus 

Fabroni S., Amenta M., Rizza G., and Rapisarda P. 

Organic acids metabolism in postharvest citrus fruit 

Cheng Y.J., Sun X.H., Zhu A.D., Xu J., and Deng X.X. 

Ethylene degreening treatment under commercial conditions does not cause loss of 

nutritional and aroma quality of citrus fruit 

Sdiri S., Navarro P., and Salvador A. 

Change in nonvolatile flavours of blood and common orange fruits during cold storage 

Fabroni S., Amenta M., Todaro A., and Rapisarda P. 

Antioxidant capacity and total phenolic contents of bergamot (Citrus bergamia) 

Yilmaz K.U., Uzun A., Ercisli S., Sengul M., Yildiz H., and Uysal O. 

Simulation of cold treatment during a cargo shipment of citrus fruits 

Tauriello A., Di Renzo G.C., Altieri G., Strano M.C., Genovese F., and Calandra M. 

Application of 3,5,6-TPA under commercial conditions to control calyx senescence 

associated to degreening treatment 

Tormo D., Conesa E., Sdiri S., Navarro P., and Salvador A. 

Postharvest behavior of new mandarins cultivars obtained at the IVIA 

Sdiri S., Navarro P., Cuenca J., Pardo J., and Salvador A. 

Characterization of fruits of four different lemon cultivars, collected in the Northern 

coast of Sicily 

Cupane M., Guarrasi V., Palazzolo E., San Biagio P. L., and Germanà M. A. 

Postharvest green mold control by hot water dips in kumquats 

Vázquez D., Cocco M., Bello F., Panozzo M., and Meier G. 

Fate of foodborne pathogens in minimal processed orange and reduction of their 

growth using UV-C illumination 

Lourenço A., Salazar M., Graça A., Quintas C., and Nunes C. 

Evaluation of the effect of ultrasonic variables at locally ultrasonic field on extraction of 

hesperidin from Penggan mandarin (Citrus reticulata) peels 

Ma Y.Q., Wu H.J., Ye X.Q., Wang H., and Sun Zh.G. 

Industrial orange (var. ‘Salustiana’) juice debittering: effects on the color and bioactive 

compounds 

Stinco C.M., Fernández-Vázquez R., Hernanz D., Heredia F.J., Meléndez-Martínez A.J., 

and Vicario I.M. 

The effect of fermentation on antioxidant content (ascorbic acid, carotenoids and 

flavonoids) and antioxidant activity (abts and dpph values) of orange juice 

Escudero B., Cerrillo I., Hornero-Méndez D., Herrero-Martín G., Berná G., Martín F., and 

Fernández-Pachón M.S. 

Study on microwave sterilization characteristics of NFC orange juice 

Wang H., Ma Y.Q, and Wu H.J. 



S21P16 

S21P17 

S21P18 

S21P19 

S21P20 

S21P21 

Equipments automation in citrus canned processing line 

Zhang J., and Lu S. 

Extension of the project for obtaining bioethanol from citrus waste 

Conesa C., Fito P., and Fito P.J. 

Sensory analysis as an instrument for colour measurement in satsuma and ‘Nova’ 

mandarin fruits 

Bello F., Vázquez D., Almirón N., Meier G., and Cocco M. 

Discrimination of three Citrus paradisi cultivars by electronic nose 

Guarrasi V., Bernik D., Bulone D., San Biagio P.L., Germanà M.A., and Negri R.M. 

Effect of several clay content in chitosan-clay nanocomposite coating on chemical 

and mechanical properties of orange fruit comparison with conventional coating 

during storage 

Torabi A.R., Hashemi S.J., and Hashemi Z.S. 

Reducing decay and physiological disorders in oranges stored at suboptimal 

temperature by combined treatments 

Artes Calero F., Velázquez P., and Artés Hernández F. 

SESSION 22: Citrus economics and trade 



Conveners: Dr. Elena MELIÁ MARTÍ (Universidad Politécnica de Valencia, Spain) and Dr. Orlando S. 

PASSOS (Embrapa Cassava and Fruit Crops Center, Nugene-Citros, Brazil) 

Oral ID Title 

S22O01 

S22O02 

S22O03 

S22O04 

S22O05 

S22O06 

S22O07 


S22P01 

S22P02 

The development of citrus industry in China during the past decade 

Deng X.X. 

Risk assessment of citrus yield based on yield minus deviate index and risk probability 

Huang S. 

Recent trends of the citrus industry in Chile 

Ortúzar J.E., and Valenzuela M. 

A critical economic analysis of advanced citrus production systems (ACPS) 

Roka F.M. 

Spanish citrus cooperatives: keys to success and challenges for the future 

Meliá Martí E., Server Izquierdo R.J.,and Lajara-Camilleri N. 

Evolution of development models for Italian organic citrus growing: economic and 

environmental aspects 

Scuderi A., and D’Amico M. 

The importance of research and technical services in the recent growth of the Southern 

African citrus export industry 

Hattingh V. 

Trends in varietal composition in Spanish citrus-growing and underlying variables 

Caballero P., Fernandez-Zamudio M.A., Carmona B., Alcon F., and de Miguel Gomez 

M.D. 

Evolution of the international citrus trade in the Valencian region 

Aznar Puente J.L., García Martínez G., Silvestre Esteve E., and Orea Vega G. 



S22P03 

S22P04 

S22P05 

S22P06 

S22P07 

S22P08 

S22P09 

S22P10 

The citrus chain in Entre Rios: characterization and economic impact of some 

technologies to increase competitiveness and equity 

Vera L.M.V., Díaz Vélez R.D.V., Banfi G.B., Garrán S.M., and Gómez C.G. 

The experience of the Entre Ríos Citrus Board, and its contribution to the citrus industry 

Vera L.M.V. 

Overview of organic citrus production in the Algarve (Portugal) 

Reis D., Fernandes M.M., Marreiros A., Mourão I., and Duarte A. 

Citrus and pomegranate cultivation: concurrence vs competition in eastern Spain 

Melian Navarro A., De Miguel Gómez M.D., and Fernández-Zamudio M.A. 

PDO and PGI citrus productions: state of the art and perspectives 

Scuderi A., and Pecorino B. 

Comparisons of fruits load estimation methods using geostatistical techniques 

Gimenez L.I., Cabrera Brunetti S.C., Avanza M.M., and Mazza S.M. 

Price evolution of ‘Clemenules’ and ‘Navelina’ in Spain in the period 2007-2012 

Server Izquierdo R.J., García-Martínez G., Lajara-Camilleri N., and Orea-Vega G. 

São Francisco Valley as a new belt for the Brazilian citrus industry 

Passos O.S., Bastos D.C., Soares Filho W.S., Girardi E.A., and Leão H.C. 


Plenary 

Conferences 

PC01 The Spanish citrus industry 

Luis Navarro 

PC02 Citrus and health 


PC03 The importance of citrus for the juice and beverage industry 


PC04 Food safety, social compliance and sustainability, in relation 

to commercial fruit and vegs strategies with special reference to 

citrus 

Gé Happe 

PC05 The experience of Huanglongbing control in Brazil 

Antonio J. Ayres 

PC06 New genetic and genomic tools for citrus breeding 


PC07 Biological control and citrus: a long time fruitful story 

Jacques Brodeur

PC01 

The Spanish citrus industry 

Luis Navarro 

Instituto Valenciano de Investigaciones Agrarias (IVIA). E-mail: lnavarro@ivia.es. Moncada, Valencia, Spain 

Citrus have a long history in Spain. Citrons were introduced by the Romans during the V century, sour oranges, 

lemons, and pummelos by the Arabs during the X and XI centuries, the first sweet oranges by the Genovese 

traders during the XV century and then higher quality varieties by the Portuguese in the XVI century, the 

mandarins during the XIX century, and finally, grapefruits from U.S.A. in the early XX century. Initially citrus 

were used as ornamental plants and for medicinal purposes, and after introduction of sweet oranges also 

for direct consumption at very local scale. Commercial plantings and exports of fresh fruit to other European 

countries started at the end of the XVIII century. 

In the past, the Spanish citrus industry has been conditioned by diseases. The first important problem appeared 

at the end of the XIX century, when about 4,000 ha of citrus were grown as seedlings or grafted on sweet 

orange, lemon, citron and sour orange rootstocks. Observations published in 1892 indicated that trees were 

dying from a disease, much later identified as Phytophthora root rot. In 10-15 years all trees in commercial 

plantings died, except those grafted on sour orange, which is tolerant to this pathogen. Consequently, all 

new plantings were established on sour orange rootstock, which has an excellent horticultural behavior and 

is tolerant to most biotic and abiotic stresses. Indeed most citrus growing countries followed the Spanish 

example and sour orange became the predominant citrus rootstock worldwide. Later this created a serious 

problem due to its high susceptibility to decline induced by Citrus tristeza virus (CTV). 

In the period 1910-1930 new higher quality cultivars were imported from different countries that were 

used for new plantings and also to change old cultivars by topworking. Evidence indicates that many of the 

imported cultivars were affected by viruses, including CTV, and viroids that spread throughout the country. 

The first CTV outbreak in Spain was recorded in 1957, and since then it has produced the death of more 

than 44 million trees of sweet oranges and mandarins grafted on sour orange. At the end of the 1960’s the 

total surface of citrus was about 210,000 ha and citrus exports were the main source of foreign currency 

for the country. The risk of a socio-economic disaster caused by CTV was so high that the Government set 

up very severe rules to reduce losses produced by the virus. The use of sour orange was prohibited in new 

plantings and propagation of plants at citrus nurseries was strictly regulated, leading to a drastic reduction in 

its number from thousands to nine. 

Early surveys and indexing disclosed that other virus and virus-like diseases were widespread in all Spanish 

cultivars. Psorosis, impietratura, and concave gum were producing important damage. Exocortis infected all 

cultivars and consequently, Troyer citrange, the best tristeza-tolerant rootstock under the Spanish growing 

conditions, could not be used for propagation. It was estimated that in addition to tristeza, other virus and 

virus-like diseases produced losses estimated at 10-25% of the total production. 

In the early 1970s graft-transmissible pathogens were the major limitation for the development and even 

for maintenance the Spanish citrus industry. It became evident that control of virus and virus-like diseases 

required the use of pathogen-free cultivars grafted on tristeza tolerant rootstocks. Since all the Spanish 

cultivars were infected, the first step was to recover healthy plants from those cultivars. The development 

of shoot-tip grafting in vitro (STG) to recover healthy citrus plants allowed in 1975 to set up a program with 

the objectives of recovering pathogen-free plants from all cultivars grown in Spain, establishing a germplasm 

bank with pathogen-free plants, and releasing pathogen-free budwood to nurseries through a mandatory 

certification program. Later, in 1983, a new quarantine procedure based on STG was developed and legislation 

was changed to allow the safe importation of citrus budwood. Thus, introduction of genotypes for commercial 

and scientific purposes was included as an additional objective of the program. 

Today the germplasm bank has more than 600 accessions protected in screenhouses that are the initial 

material used by all nurseries to produce plants under the certification program. Nurseries started to sell 

certified plants originated in the Program in 1982 and until now they have sold about 140 million plants, 

representing more than 97% of the Spanish citrus industry. 

XII INTERNATIONAL CITRUS CONGRESS 2012 - 3

Drip irrigation introduced in the 80’s allowed cultivation in hilly and relatively poor soils, thus allowing an 

important expansion of citrus to new areas. The availability of healthy plants, together with important 

improvements of cultural practices produced an increase in yields and fruit quality. 

Today Spain has about 330.000 hectares of citrus, with an average production of 6.5 million tones/year, with 

sweet oranges representing 48%, mandarins 35% and lemons 16%, although the tendency in new plantings 

is to reduce sweet oranges and increase mandarins, according to the preferences of consumers. Spain is the 

first exporting country of fresh fruit, with more than 50% of its production being commercialized abroad. 

About 20% of the production is consumed in the internal market also as fresh fruit, 18% is processed and the 

rest is waste. Citrus plantings are mainly located along the Mediterranean coast in the provinces of Tarragona, 

Castellón, Valencia, Murcia, Almeria and Málaga, in the Guadalquivir river valley in the provinces of Córdoba 

and Sevilla and in the Atlantic coast in the province of Huelva. 

Since the Spanish citrus industry has been completely renewed in the last 30 years with healthy certified 

nursery trees, graft and vector transmitted diseases do not pose significant problems any longer. Today, the 

only disease problem is caused by Alternaria alternata, which produces significant damage in susceptible 

mandarin varieties like Fortune that is being replaced by others. 

Cultivars have always been a key aspect of the Spanish citrus industry due to the need to adapt production 

to the international market demands. The competitiveness is dramatically increasing in citrus international 

markets and economic survival of the Spanish citrus industry highly depends on availability of new improved 

cultivars that meet the increasing market demand for higher quality fruits. The main varieties selected in Spain 

or imported through the Quarantine Station are available for commercial propagation. However, there is still 

an important demand for new late maturing seedless mandarin cultivars. Recently two triploid cultivars with 

these characteristics, ‘Garbí’ and ‘Safor’, have been released and are being widely accepted by the growers. 

Without significant technical constraints, the Spanish citrus industry faces several new problems. Production 

cost is very high compared to those of direct competitors’ countries, mainly due to high labor costs but also 

to the small size of plantings in traditional citrus areas. The amount of different fruits reaching the markets 

in some periods is higher than the demand and this reduces the price, drastically diminishing benefits of the 

growers. To overcome this situation it is very important to increase research activities to obtain new products 

of higher quality at lower costs. 

PC02 

Citrus and health 


School of Food Science and Nutrition. University of Leeds. Leeds, United Kingdom 

Although diet clearly affects health and disease risk in many ways, the beneficial effects of fruit and vegetable 

consumption is now a well established concept. The effect of individual components of the diet on health 

is difficult to entangle, since the diet consists of many components and disease progression is a biologically 

and biochemically complex process. In general, citrus fruit contributes to the intake of “5-a-day”. Specifically 

oranges and other citrus fruits contain several components which may affect health in a beneficial way. Of 

these, vitamin C, carotenoids and polyphenols have received the most intensive research efforts in recent 

years. These components are retained during gentle processing of citrus fruits into juice. Hesperidin and 

naringenin are the most abundant polyphenols, and are found at very high levels in oranges and grapefruit 

respectively, and are unique to citrus fruits. Orange juice can contain hundreds of milligrams per portion 

of hesperidin, and this intake can make a major contribution to the overall dietary intake of polyphenols 

in many countries. Hesperidin consumption helps preserve vascular function and reduces blood pressure 

in overweight individuals, and reduces endothelial dysfunction. Hesperidin is absorbed in the colon and is 

dependent upon the presence of colonic microflora. Vitamin C performs several functions in the body, is 

essential for prevention of scurvy and may have additional health benefits related to antioxidant action. The 

lipid-soluble carotenoids also have certain antioxidant health benefits and are beneficial for cardiovascular 

function. These different components from citrus fruits provide benefits to health which can help to reduce 

the risk of chronic disease and maintain the general healthiness of the population in many countries. 

4 - VALENCIA CONFERENCE CENTER, 18th-23rd NOVEMBER 2012

PC03 

The importance of citrus for the juice and beverage industry 


Grove 2 Glass Trading GmbH, a ‘The Coca-Cola Company’ subsidiary. Zürich, Switzerland 

The Juice Industry - as any other industry – needs to manage the short-term while planning, executing and 

managing the long-term needs. Over-emphasis on the short-term leaves us exposed on those longer-term 

challenges that are quite specific to our Industry – nature does not operate on a quarterly basis - and many of 

the decisions that we are required to take to ensure the future prosperity of our business need a multi-year 

and multi-decade perspective and financial commitment. So while the short-term outlook for sales is both 

challenging and volatile, we need, as companies and as an Industry, to continue to plan for the future. 

Our vision of operating in Juices is the result of a three pronged strategy applied consistently wherever we 

operate: 

• Sustainable sourcing: We have set out to partner with growers, processors and juice suppliers to ensure 

long term supply of juice at competitive prices, while minimizing our environmental footprint, benefiting 

the communities where we operate and ensuring we receive juice that consistently meets our stringent 

quality standards. 

• Implementing efficient operating practices: Marketing fruit juice demands a completely different 

approach when compared to other beverages: convert juice ingredients into packaged juice & deliver to 

customers through a “Fit for Purpose” juice operating model supported by the right processes, advanced 

analytics and sensory science. 

• Delivering compelling consumer propositions led by a Global “Master Brand”: We have united multiple 

local brand names under a single mainstream global umbrella brand that shares common Visual Identity 

System, brand architecture and integrated marketing communication and spans multiple juice product 

segments. 

• A scientific approach to preserve and grow the business: It’s our belief that the historical model of 

segmentation of the Industry in three isolated production chains is not valid anymore. Growing, 

Processing and Marketing are part of the same effort to secure the viability of the Industry in the long 

term. And all of those legs of the juice business demand continuous scientific support: to Grow (irrigation, 

fertilization, plant protection, better varieties); to Process (high yields, less waste, energy conservation, 

less water usage, quality) and to Market (quality, sensory, obesity, water and carbon footprints). And 

Social Responsibility covering every single step from the Grove to Glass. 

• At the end, the business is supported by four legs instead of three: Grow, Process, Market and Science. 

As the rest, scientists are not expected to remain isolated on their fields of expertise. An integrated 

approach inside the various branches of Science is now necessary. Economics are necessary in the posgreening 

era of planting; Sensory is necessary in processing; Environmental is necessary in the whole 

production chain. New scientific fields are a challenge to which the scientific community has to respond 

quickly. 

• A dedicated juice procurement organization: If we are to succeed in building scale and driving growth 

we have to safeguard the essential fuel of our industry – a continuous supply of the highest quality 

juice at competitive costs. To ensure this, we set up a dedicated juice procurement arm based out of 

Zurich –G2G Trading Services GmbH–, with fruit and procurement experts embedded in the key growing 

regions around the world. Through this team we are building long term relationships with growers and 

processors. 

• Developing new production areas: In some cases we are committed to significant investments in new 

fruit growing projects, via long term supply agreements thus safeguarding our supply and enabling future 

growth. We have reinvented our overall approach to juice from the Grove, where our fruit is grown, to 

the Glass where it is consumed. Our Grove to Glass philosophy is now embedded in everything we do in 

juice and provides us with both a strong business philosophy and a roadmap for our future growth. And 

again, Science is most needed to adapt varieties to other environments, to produce more convenient 

varieties, to increase yields. 

Our industry faces many challenges: 


Global warming and its impact on climate patterns are influencing the availability, cost and yield of fruit and 

the increasing impact of disease is a barrier to investment in groves despite high prices and Industry growth. 

Add to this the increasing consumer intolerance for agricultural chemical residue at any level and we have a 

set of challenges that are truly unique. 

Juice is not immune from the Obesity challenge and the Industry is increasingly having to defend its role in 

the diet. 

Given the rise of social media and social consciousness and the need to deliver on our commitments to 

sustainability we must as an industry and as individual companies preserve and nurture our license to operate 

in all of the communities that we touch in an extremely complex global supply chain. 

Huanglongbing (HLB) is the greatest threat to the future of our industry, affecting not only oranges but all 

citrus. But, HLB is not the only threat. Citrus Canker remains a threat, CVC, Tristeza, Sudden Death, fruit flies. 

It is essential that our scientists, around the globe, remain committed to research on prevention and cure in 

order to safeguard our future. And it is essential that the governments, society and the industry continue to 

support the science applied to agriculture and, particularly, to citrus – the biggest item in the whole global 

juice Industry. And not only orange: the whole citrus. Science is complex, expensive and challenging but 

essential. Gathering such a high number of talented scientists in this International Citrus Congress shows that 

the scientific community understands and is up to the challenges – today and in the future. 

We need to know where our fruit is coming from and that our agricultural practices are sustainable. 

Consumers, NGO’s, governments and the industry will not accept agricultural practices that threaten water 

and other natural resources. 

We need to work on dealing with our issues and we have to work on marketing our category and the unique 

benefits that only juice can offer. It is our responsibility to ensure that the generations to come can enjoy the 

benefits of this wonderful natural product. 

PC04 

Food safety, social compliance and sustainability, in relation to commercial fruit and vegs 

strategies with special reference to citrus 

Gé Happe 

European Sourcing Director Ahold. Zaandam, The Netherlands 

Most times, growers blame retailers for their poor revenues (mostly discount chains). But we, as retailer, 

face a competitive world. Consumer continuously asks for better prices and higher quality. Now in this time 

of crisis, the price factor becomes really important. But to focus only on price can have serious undesirable 

consequences. When retailer sells cheaper, he has to buy cheaper. When grower receives lower revenues, 

he has to produce cheaper, usually paying less attention to quality as “nobody pays for it”. But when finally 

consumer perceives lower quality at shops, he does not like it and does not buy. And all the money invested 

in the supply chain, even if lower, gets lost. 

Therefore, the model AH has been developing in the latest 50 years is a model of partnership. Quality is a 

MUST. But at the same time, teamwork with all players in the supply chain, being directed by the same goal 

(consumer satisfaction), allows to look for all possible efficiencies in the chain, to reduce cost and transmit 

that effort to consumer. In that sense, consumer is receiving a better quality at a more reasonable price. 

However, we are all living in a dynamic context. Citrus varieties evolute and logistics also improve. New 

shipping lines arise, more a modern frigo containers appear and new fruit terminals are built in new production 

areas. Then it is easier to sell citrus from wherever production area to wherever retailer in the world. That’s 

globalization and nobody can stop it. We are selling at winter time nearly all our citrus from Spain. And we 

have to face the concurrence of other retailers selling from other production areas in the Mediterranean. As 

retailer, we (AH) apply strict policies in food safety and social compliance, so all growers from wherever origin 

can compete on equal conditions. We understand that reduction of pesticides has an implicit cost. Social 

Security, safety at work, working in legal and reasonable conditions have costs. But citrus is synonymous of 


Health. We have to guarantee our consumers that what they buy in our shops is healthy. And furthermore, 

that those citrus have been grown packed and transported in legal and safe conditions. 

Spain is a privileged area. Since centuries, weather and soil have provided the optimal environment for 

growing citrus. But the global context also counts. Therefore, we all are obliged to keep on working on the 

same axes: quality and efficiency. As grower, sometimes size can be a difficulty. There are several production 

areas, like in the Valencia Region, where orchards average surface is quite small. Maybe getting closer to a 

professional good organization with good positioning in the market, good knowledge of varieties and trends 

could help. On efficiency, maybe working together and sharing cultural practices costs could help small 

growers. I understand it is always better to do everything by yourself, not depending on anyone. But, unless 

you are big enough and efficient enough, world is pushing in the other direction: teamwork. 

To keep a place in the market is always a challenge. And we all have to work hard to achieve it. But I invite you 

all to take profit of your unique conditions and keep on making consumers from all over the world, enjoying 

these magnificent fruits you are able to produce. 

PC05 

The experience of Huanglongbing control in Brazil 

Antonio Juliano Ayres 

Fundo de defesa da citricultura (FUNDECITRUS). Brazil 

Symptoms of Huanglongbing (HLB) were first reported in São Paulo State (SPS) near Araraquara in 2004. 

However, the insect vector, the Asian citrus psyllid, Diaphorina citri, has been present in SPS since 1940 and 

is responsible for the spread of HLB to most regions of SPS. 

Immediately after HLB was identified in March 2004, Fundecitrus recommended HLB-management in all 

the citrus farms of SPS as an attempt to control the disease and save the industry from destruction. The 

management involved three classic measures: (i) insecticide sprays of all trees, several times a year, to decrease 

the insect-vector population, (ii) identification and immediate removal of symptomatic trees, several times a 

year, to rid orchards of sources of inoculum, and (iii) replacement of removed trees by young, HLB-free trees 

from covered, insect-proof nurseries. HLB-management by this “three-pronged system” (TPS) was evaluated 

by determining the total number of symptomatic trees removed each year in the various blocks. Indeed, 

successful management would result in decrease of the total number of symptomatic trees removed per year, 

while unsuccessful management would lead to an increase of such trees. 

Since 2004, crucial factors having a strong influence on HLB-management by the TPS have been identified. 

1) HLB incidence in the region where the farm is located and 2) HLB incidence in the farm. For instance, 

when HLB is first detected in a region or country where the psyllid vector has been present for some time 

(Brazil in 2004, Florida in 2005, Texas and California in 2012) the incidence of the disease is generally low. 

HLB management by the TPS is easier when the HLB incidence at onset of the management is low (≤ 7%). 

3) When a farm with good HLB management is close to a farm with no or poor management, HLB-control 

in the “good” farm becomes much more difficult because the highly infected psyllids from the “poor” farm 

invade and contaminate the “good” farm. In this case, more aggressive psyllid control has to be applied 

in the contaminated periphery of the good farm 4) HLB-control was found to be easier when applied to 

large orchard surfaces (≥1000ha) rather than to smaller ones. 5) Young orchards which have multiple flushes 

were more susceptible than mature ones with lesser flushes and required systemic insecticides to achieve 

better control of the psyllid-vectors. In contrast to the five above factors which are characteristic of the 

farm at onset of the management, the following factors are those that can be modified and through which 

management can change the HLB incidence in the farm: 1) Number of inspections for early detection and 

removal of symptomatic trees. The use of tractor-pulled platforms with two or four inspectors made surveys 

more efficient and less strenuous. 2) Number of psyllid control operations, nature of insecticides, application 

methods, prevention of insecticide resistance. 3) Acording to the HLB incidence, removed trees are replaced 

or not replaced by reset trees. 4) Old, lesser productive citrus blocks are removed to prevent their role as 

sources of inoculums (restructuring). 5) Last but not least, it was recommended that HLB-management be 


egional, i.e. applied on an area-wide scale, including either many growers with small/middle size farms or 

only a few growers with large farms. 

The surveys conducted by Fundecitrus in 2011 on the incidence of HLB in SPS have confirmed that the 

efforts of the Citrus Industry to control HLB since 2004, when HLB was first identified in SPS, have met with 

success. The results of these surveys show that more than 200,000ha (500,000acres) of citrus orchards, 

i.e. more than one third of the total SPS citrus acreage, have an HLB-incidence as low as 1%. This level 

might even become lower as many citrus orchards with poor management and high HLB-incidence had to 

be removed or turned into fields of sugar cane: they are no more a serious danger for the well-managed 

neighboring farms. These 200,000ha of well-managed citrus farms with low HLB incidence prove that HLB– 

management has been successful in many parts of SPS, including regions of high initial HLB incidence, and 

that a large part of the Paulista citrus industry has survived HLB. Furthermore, in the years to come, more 

farms with low HLB-incidence might be seen because HLB-management will probably become easier. 

All these farms with low HLB incidence represent the “hard-core-orchards” on which the future of the citrus 

industry will be constructed. Research is under way in SPS to produce “new generation” citrus trees resistant 

to HLB or protected from infection by the psyllid-vectors. When these genetically modified trees (GMTs) will 

become available, in five to ten years, the hard-core-orchards with low-HLB-incidence, will offer the proper 

conditions for rapid growth and development of the young, new-generation GMTs. It is even well possible 

that the healthy, non-genetically modified trees from the successful TPS system can be kept in parallel with 

the GMTS, giving SPS two options for the future: orchards with GMTs in the regions of high HLB incidence and 

orchards with essentially healthy, non genetically modified trees. 

At this moment, Brazil is the only country in the world where HLB control is effective on a large scale. In other 

parts of the world, HLB could not be met with proper management. Worse, methods have been recommended 

and/or adopted, which result in a dramatic increase of HLB-incidence. Such methods should not be used in 

SPS as a substitute for the successful HLB-management developed in the region. 

PC06 

New genetic and genomic tools for citrus breeding 


Department of Botany and Plant Sciences. University of California, Riverside, CA, USA 

Citrus breeders face many challenges in their quest to develop scion and rootstock varieties that provide 

growers with productive, disease resistant trees and consumers with tasty, high-quality and nutrientpacked 

fruit. Three major approaches are used to develop new cultivars: mutation, hybridization, and 

gene introduction (transgenics). In citrus, mutation breeding has been used mainly to develop low seeded 

cultivars, but in annual crops it has also been used to improve many other traits because it is easier and 

less costly to screen very large numbers of plants. Breeders identify rare mutants that express useful traits 

and then transfer the mutant gene into other cultivars by hybridization methods. In citrus and other fruit 

crops with long generation times and in which the elite genotypes used as commercial cultivars are very 

heterozygous, such breeding is so difficult that it has rarely been attempted. Several new developments 

promise to facilitate this relatively conventional approach to breeding. Cultural practices to shorten the 

juvenile stage are being more widely used and may reduce the generation time of citrus to about 3 years. 

Transgenic varieties with reduced juvenility have also been developed and could facilitate transfer of 

novel mutations into other cultivar types. A shorter generation time makes multiple generation breeding 

much more feasible. Targeted mutation is another potential approach for citrus breeding. One approach, 

commonly called TILLING, screens specific genes in a large population of mutagenized plants to identify 

individuals with mutations in the targeted gene. This method requires knowledge of gene function to 

identify the target gene or genes, but knowledge of gene function is developing rapidly in citrus and many 

potential targets are already known. An alternative approach, sometimes called targeted gene modification, 

is to express genes for enzymes such as zinc-finger nucleases (ZFN) that induce chromosome breaks at 

specific target sites. Repair of these breaks is frequently imprecise, resulting in small deletions or insertions 

at the cleavage site. Many such mutations will affect the phenotype. At present, transgenes are introduced 

that specify these enzymes and they are removed from the genome by segregation in later generations. 


In citrus, it would be difficult to recover the elite cultivar (such as a sweet orange) following a cross, so an 

alternative method to introduce these ZFN genes will be needed. Such genes could be carried on a virus 

that infects the initial cultivar and is later removed by thermotherapy or shoot-tip grafting before the new 

mutated cultivar is released. These approaches will allow breeders to reduce or eliminate function of one 

copy of a gene. To have a phenotypic effect, the mutation would have to have some level of dominance. In 

annual crops new mutations are commonly made homozygous by selfing or sib-mating, methods that are 

either not possible in citrus or which yield progeny very unlike the parental cultivar type. Possibly targeted 

gene modification can be efficient enough to produce mutations in both alleles. It is also important to 

recognize the limits of these methods – they produce mostly loss-of-function mutations, and not all desired 

phenotypes can be created by such mutations. 

High quality reference genome sequences for citrus have been developed by the International Citrus 

Genomics Consortium (haploid from clementine), the University of Florida (diploid sweet orange) and 

Huazhong University (haploid of sweet orange). With these reference sequences available, advances in 

genome sequencing now make it simple and inexpensive to determine most of the genome sequence of 

interesting mutants and cultivars. Comparison of sequences from a few varieties indicates the ancestral 

species that contributed each chromosome segment to hybrids and may even indicate the precise 

genotype of each parent. Comparative genome sequence information will allow identification of candidate 

genes that may cause phenotypic differences among cultivars derived by mutation (navel oranges with 

different maturity dates, grapefruit differing in flesh color etc.). Once genes are known, they can be more 

easily transferred to other cultivar groups by hybridization-selection, transgenics, or targeted mutation 

approaches. Breeding by hybridization-selection methods is also increasing in efficiency through use of 

genome sequence information and methods. Several groups have now developed SNP arrays that can be 

used to rapidly determine the overall genotype of each individual progeny. Projects that required years of 

work using “one at a time” markers such as SSRs can now be completed in a few weeks. Genotyping-bynextgen 

sequencing methods, in which a defined fraction of genome fragments is sequenced in multiplex, 

is another approach to this end. Development of these methods, particularly when combined with gene 

expression studies, will greatly facilitate identification of genes that confer disease resistance, fruit quality 

and other important traits. Efficient, high-density genotyping should also facilitate identification of progeny 

plants that resemble specific genotypes such as sweet orange or clementine and thereby allow breeders 

to develop hybrids that closely resemble these cultivars except for chromosome segments carrying desired 

genes. These technologies will reduce the “random” element in hybridization-selection breeding, but 

exploiting them will not be inexpensive because achieving these objectives will require molecular analysis 

of large populations. 

New methods also promise to revolutionize development of citrus cultivars using transgenic approaches. In 

the past, nearly all transgenes were introduced using methods such as Agrobacterium or biolistics that result 

in integration at more or less random locations in the genome. The genomic context in which a transgene 

integrates can affect its expression and this contributes to the need to screen a large number of transgenics 

to find those with appropriate expression levels. Random integration also complicates regulatory review 

of transgenics. Targeted integration of transgenes is now possible by engineering a “founder line” having a 

construct with good gene expression and an integration site developed with a recombinase-mediated cassette 

exchange strategy. Such lines can then be transformed with additional genes that will be integrated at this 

site. Another significant opportunity is development of cis-genic varieties in which the added DNA originates 

from citrus rather than from an unrelated species. It is possible to envision systems in which all genes 

introduced, including selectable markers, originate from citrus sequences. Such varieties may encounter less 

public opposition than those that contain genes from a non-citrus species. Despite the potential power and 

promise of these new tools, real progress will also depend on accurate plant phenotyping and subsequent 

field trials to identify superior cultivars. Success will also be facilitated by sharing information widely in the 

citrus community because there are many challenges to be addressed and few citrus breeding groups to 

address them. 


PC07 

Biological control and citrus: a long time fruitful story 

Jacques Brodeur 

Plant Biology Research Institute. Montreal University, Montréal, Qc, Canada. 

From the earliest days, agriculture has been plague by pests. Growers have to deal with outbreaks of insects, 

weeds, and plant pathogens. There has been a continual increase in arthropod pest species invading citrus 

over the past century. Citrus systems are replete with mite and insect pests, both in terms of their abundance 

and diversity. Growers rely on several approaches to pest control, including mechanical, cultural, chemical 

and biological methods. In this conference I outline the practice of biological control. 

Biological control refers to the use of living organisms, or products derived from living organisms, such as 

toxins, for control of insect pests, weeds and plant diseases 

Biological control is considered by many to be the best alternative to pesticides. Biological control is efficient, 

safe for humans and the environment, and in most cases cheaper than chemical control. Natural enemies 

exert a significant, continuous and naturally level of pest population regulation in natural or managed 

ecosystems. Biological control also refers to the deliberate introduction of specific natural enemies to control 

specific populations of weeds, plant diseases or insect pests. Such an approach may involve the discovery 

and release into a crop of natural enemies, and in some instances their production and commercialization as 

biological control agents. At least 7,000 introductions of natural enemies involving almost 2,700 species have 

been made worldwide. The most widely used species have been introduced into more than 50 countries. 

In augmentative biological control, more than 170 species of natural enemies are produced and sold, but 

some 30 species make up more than 90% of the market worldwide. Biological control has a long tradition 

of success in citrus. In 1868, the cottony-cushion scale was found on acacia in California. Ten years later the 

citrus industry was at the verge of collapse because of the scale. Natural enemies were sought in the native 

home of the pest, southern Australia. This search resulted in the introduction into California in 1888 of a 

coccinellid predator, Rodolia cardinalis. The voracious beetle rapidly became established and by late 1889 

the cottony-cushion scale was no longer regarded as a threat to citrus. The beetle saved the American citrus 

industry and has since become an icon in biological control. 

By creation of partnerships that brought together growers, researchers and biological control companies, the 

citrus industry has since undertaken a transition from total chemical control to a balance of biological control and 

integrated pest management. Because the arthropod community in citrus is very complex, it remains challenging 

to conduct biological control and to predict the impacts arising from interactions among biological control agents, 

landscape structure and pesticide use. Understanding these factors will help to develop sustainable ecosystem 

communities that can maintain pest densities below economically damaging thresholds. A current challenge 

relates to the introduction of exotic pests and the subsequent release of exotic natural enemies. Due to its 

overall ecological complexity, the citrus orchard is characterized by high level of both stability and capacity for 

self-regulation. However, this condition is repeatedly jeopardized by a significant increase of exotic citrus pests 

in all producing areas. There is therefore a growing requirement for improved quarantine services and classical 

biological control programs that remains the best tool to tackle existing and future alien pest problems. But the 

biological control sector is facing increasing problems with access to natural enemies since the international 

Convention of Biological Diversity and its Access and Benefit Sharing regime. This situation has added another 

level of regulation that may slow, and even stop in certain countries, the use and exchange of biological control 

agents around the world. Global climate change is another growing concern for pest management in citrus 

orchard. The increasing temperatures, elevated carbon dioxide and changes in rainfall patterns associated with 

climate change will affect pest management programs and the movement of exotic organisms. In the near future 

we will need to modify the carefully developed pest management programs to respond to climate changes. The 

citrus industry will soon have to deal with changes in pest and beneficial species assemblages, developmental 

ranges and degree of synchrony between interacting species. 

Biological control creates and sustains public good – food security, food quality, reduced pesticide use, human 

(farmer and worker) health, invasive alien species control, protection of biodiversity, and maintenance of 

ecosystem services. However, the adoption of biological control worldwide has lagged behind our scientific 

understanding of its potential. Development of biological control for citrus is a dynamic, constantly-evolving 

challenge. Perseverance is critical. 


Workshops 

W01. HLB Control 

Convener: J. Bové 

W02. New mandarin varieties 

Convener: P. Aleza 

W03. Procedures for the exploitation of protected and/or patented 

varieties 

Convener: M. Iborra 

W04. New perspectives in pest control 

Convener: A. Urbaneja 

W05. Dwarf citrus trees in high-density plantings 

Convener: K.D. Bowman 

W06. Molecular identification of varieties 

Convener: T. Shimizu 

W07. Mechanization of citrus harvest 

Convener: E. Moltó 

W08. Global citrus industry collaboration on MRL regulatory issues 

Convener J.R. Cranney Jr. 

W09. Global conservation strategy for citrus genetic resources 

Convener: K. E. Hummer 

W10. Research activities to support the potential biological effects 

of citrus fruits in human health 


W11. Quarantine security for tephritid fruit fly pests in citrus 

Convener: N.J. Liquido

W01 

HLB control 

Convener: J.M. Bové 

Université de Bordeaux Ségalen. INRA Center, Bordeaux-Aquitaine (France). E-mail: joseph.bove@wanadoo.fr 

The University of Florida estimates that in the State, HLB has resulted in the loss of more than 6,600 jobs, $1,3 

billion in revenue to growers and $3,6 billion in economic activity. Can HLB be controlled, how and when? 

Answering these questions is the goal of the workshop! Two forms of HLB have to be considered: (i) high 

temperature-sensitive African-HLB, with Candidatus (Ca.) Liberibacter (L.) africanus and the African Citrus 

Psyllid, Trioza erytreae, and (ii) high temperature-tolerant Asian-HLB, with Ca. L. asiaticus and the Asian Citrus 

Psyllid, Diaphorina citri (2). African-HLB is presumed to be less aggressive than Asian-HLB. 

There is little or no evidence of genetic resistance to HLB in citrus. Apparently, citrus has had only a recent 

association with Liberibacter species, an association too short to have built up resistance to the bacterium. 

Hence, according to a general consensus, resistance to HLB will probably be obtained by engineering, into 

citrus, genes with anti-Liberibacter and/or anti-psyllid activity (8). However, such HLB-resistant cultivars will 

probably not become available to the growers for several years and, in the meantime, solutions must be 

developed to control HLB and save the existing citrus industry from destruction (1, 3, 9). Thus, for HLB control, 

short-term systems for “today” and long-term systems for “tomorrow” must be discussed. 

Short-term systems. Even though they are called “short-term”, these systems, when efficient, will probably 

have to be used for several years. Various systems are known and listed. (i) The classic, Three-Pronged 

Package (TPP) has been recommended in China since the 1950s and is comprised by (a) insecticide treatments 

against psyllids, (b) detection and removal of symptomatic trees, and (c) resets with disease-free trees from 

insect-proof nurseries. TPP is a “preventive” control system; as it “prevents” trees from becoming infected. 

Application of the TPP in São Paulo State, Brazil, since 2004 when HLB was first identified, has resulted in two 

hundred thousand hectares of citrus with less than 1% of HLB-affected trees, even in areas where the initial 

HLB incidence was high. In Florida, growers were reluctant to remove symptomatic trees and the TPP system 

has not gained much acceptance, except in some large citrus farms (6). Factors having a significant influence 

on the efficiency of the TPP system, including restructuring, will be highlighted (1). For instance, HLB control 

was found to be easier in large farms than in smaller ones. “Regional” management overcomes this problem 

in Brazil. In Florida, “Area Wide Control of Psyllids” has been developed and “Citrus Health Management 

Areas” have been established (8). Ways to improve the detection of symptomatic trees (rapid field detection 

methods, hyperspectral imaging, biomarkers, etc) and the treatments against the Asian and African citrus 

psyllid (biological control, insecticides, application methods, prevention of insecticide resistance, flush control, 

overwintering sites, etc) should be discussed. (ii) Foliar sprays of micronutrients, with or without inducers of 

Systemic Acquired Resistance (SAR), are also believed to give immediate protection against HLB. However, 

this system in which no tree removal is practiced, rapidly results in a high percentage of HLB-infected trees, in 

spite of good psyllid control (5, 9). The effect of nutritional treatments on HLB-control, fruit-quality, bacteriatiter 

and disease-progress has been challenged recently and found inconsequential (5). (iii) In the Mekong 

delta of Vietnam, farmers have found that the presence of guava trees surrounding citrus trees (interplanting) 

prevents or at least retards HLB. Volatiles from guava repel the Asian citrus psyllid, thus explaining the guava 

effect. However, recent experiments in Vietnam have shown that efficacy of guava interplanting on HLB is 

limited, as the effectiveness of guava against disease invasion breaks down after one year, probably because 

citrus trees outgrow guava trees (7). (iv) Advanced Citrus Production System (ACPS). The aim of the ACPS 

is to shorten and enhance the citrus production cycle through high density plantings, as well as intensive 

computerized daily fertirrigation (Open Hydroponics System) for automated irrigation and intensive nutrient 

management. (v) Additional short-term systems might be brought up from the floor and discussed. 

Long-term systems. Long-term systems are still at the research and/or the experimental level, even though 

some are already under evaluation in the greenhouse and/or the field. These systems involve the production 

of genetically modified citrus plants expressing anti-Liberibacter and/or anti-psyllid genes (8). In one system, 

these genes are inserted into the citrus genome through classic Agrobacterium-mediated transformation. 

Transformation of mature citrus tissue ensures that the resulting transgenic cultivar is true to type, but 

seems to be more difficult to achieve than transformation of juvenile tissue. In a second, more recent system, 


meant for regions where citrus tristeza virus (CTV) is endemic, the anti-HLB gene is first incorporated into the 

genome of CTV, thus using the virus as a gene vector (4). Inoculation into citrus of the CTV strain carrying the 

ant-HLB gene results in viral replication and expression of the viral proteins as well as those of the anti-HLB 

protein from the anti-HLB gene. 

Genes used for resistance to Liberibacter spp. have essentially been anti-bacterial peptide genes from various 

sources (including plants) and genes involved in systemic acquired resistance. Recently, single-chain-fragmentvariable 

(SCFV) antibodies have been produced. For the first time, SCFV antibodies are now available against 

almost any Liberibacter protein. Candidate SCFV antibodies for resistance to HLB are those directed against 

proteins found to be essential for Liberibacter growth and replication. Combination of the CTV gene vector 

and the SCFV anti-HLB antibodies might become a most efficient anti-HLB system. Liberibacter phage for 

potential control of HLB has also been proposed. 

Anti-psyllid transgenic cultivars are developed to express volatile chemicals repelling the psyllids. Doublestranded 

RNA corresponding to an essential psyllid gene can also be used to transform citrus cultivars, 

hopefully resulting in mortality and suppression of the feeding psyllids through RNA interference 

However, all these genetically modified plants (GMP), would have to be accepted by the consumers (from 

Europe in particular) before products from such GMPs can be marketed. 

References 

(1) Belasque Jr. et al. 2010. Lessons from Huanglongbing management in São Paulo State, Brazil. Journal of Plant Protection 92: 285- 

302. 

(2) Bové, J. M. 2009. www.ivia.es/iocv Citrus diseases, Huanglongbing, text and image gallery. 

(3) Chamberlain, H.L. 2010. Importance of awareness to growers, nursery growers and residents for the control of HLB and its 

vector. 2 nd international workshop on Huanglongbing and Citrus Asian Psyllid, Merida, Yuc., July 2010, . 

(4) Folimonov, A.S. et al. 2007. A stable RNA virus-based vector for citrus trees. Virology, 368:.205-216. 

(5) Gottwald, T. R. et al. 2012. Inconsequential effect of nutritional treatments on Huanglongbing control, fruit quality, bacterial titer 

and disease progress. Crop Protection 36:73-82. 

(6) Irey, M.S. 2010. Experiences of one Florida grower with the management of Huanglongbing—Success over time. 2 nd international 

workshop on Huanglongbing and citrus Asian psyllid, Merida, Yuc., July 2010, . 

(7) Katsuya, Ichinose et al. 2012. Limited efficacy of guava interplanting on citrus greening disease: Effectiveness of protection 

against disease invasion breaks down after one year. Crop Protection 34:119-126. 

(8) National Research Council. 2010. Strategic Planning for the Florida Citrus Industry: Addressing Citrus Greening Disease. 

Washington, DC: The National Academies Press. 

(9) Timmer, L. W. et al. 2011. It’s not too late – yet. Citrus Industry, January 2011: 6, 7. 

W02 

New mandarin varieties 

Convener: Pablo Aleza 

Centro de Protección Vegetal y Biotecnología. Instituto Valenciano de Investigaciones Agrarias (IVIA). Moncada, Valencia (Spain) 

E-mail: aleza@ivia.es 

One of the major issues occurring during the last three decades was the increase of the fresh fruit market 

of mandarins. For clementines and satsumas, new cultivars have only been selected from spontaneous or 

induced mutations while both mutant selection and breeding programs have allowed varietal progress in 

other type of mandarins. 

In relation with specific market demands and environmental conditions (biotic and abiotic constraints), the main 

goal of breeding may vary strongly between the production areas. Expanding the harvesting period with high 

quality seedless fruits is currently the main objective of new mandarin varieties for the fresh fruit market. This 

market promotes organoleptic qualities (aroma, taste, acidity, sugar) and pomological qualities (easy to peel, 

seedlessness, external appearance). The definition of organoleptic quality can vary according to the consumers. 

Citrus breeders must therefore endeavour to develop a wide range of varieties likely to meet these diverse needs. 

Nutritional quality based on vitamin C, carotenoid and polyphenol contents are now considered as breeding 

criteria in some projects. Some diseases cause considerable damages in orchards. Huanglongbing in Asia, South 

Africa and recently in Brazil and Florida, citrus canker in most tropical and subtropical areas, cercosporiosis 

in Africa, citrus variegated chlorosis and Sudden death in Brazil. Alternaria also becomes a problem for some 


mandarin cultivars such as `Fortune´ in Spain. Ranges of varietal susceptibility have been established for most of 

these diseases and tolerant parents are selected in some breeding programs. 

Conventional breeding in citrus has important limitations due to the complex reproductive biology of these 

species. Most genotypes are apomictic and adventitious embryos develop directly from nucellar cells limiting 

or precluding the development of zygotic embryos. This limits the recovery of large sexual populations and in 

practice apomictic genotypes are avoided as female parents in many programs. Several high quality genotypes 

have pollen and /or ovule sterility and thus cannot be used as parents in breeding programs. Self and crossincompatibility 

are relatively common among many genotypes, also limiting the possibilities to select parents 

for specific crosses. They have a very long juvenile phase and in most species at least five years are required 

to star flowering and many more to completely loose the undesirable characters associated with juvenility. All 

this aspects, together with large progeny size hamper setting up breeding schemes over several generations 

and are the main reason for the relatively low success of conventional breeding programs carried out so far. 

Citrus breeders, taking advantage of vegetative propagation, put their main effort in the research or 

induction of polymorphism on one cycle from which they made clonal selection. Selection relates thus, either 

to spontaneous mutation identified in the orchards, or on genotypes obtained by hybridizations, induced 

mutagenesis or after recourse to biotechnologies that have been strongly developed in citrus in part to solve 

the problems found in conventional breeding. The main methodologies used are: 

• Mutants’ induction 

Selection of spontaneous mutations is the oldest citrus breeding method and most of the varieties 

cultivated worldwide arose from this process. In Spain, Morocco and Corsica, it has provided good results 

for clementine, by extending the production period and enhancing fruit size and color. On a much longer 

time scale, similar results have been obtained for Satsuma mandarins in Japan. 

A number of experiments of induced mutagenesis were carried out since 1935 for cultivar improvement. 

Gamma irradiation has been the most common method of mutagenesis. Examples of mandarin cultivars 

obtained by irradiation programs are the low-seeded selection of `Murcott`, called `Mor´, low-seeded 

selection of `Clemenules´ clementine named `Nulessin´, and the seedless mandarin `Tango´ produced by 

irradiation of Àfourer´ (Nadorcott) budwood. 

• Sexual breeding at diploid level 

Sexual breeding is mainly used for diversification in mandarins. The main limitation of this strategy is that 

most of the diploid hybrids are fertile and thus seedy. The selection of seedless cultivars displaying high 

quality and good yield requires the evaluation of very large progenies. Moreover, if seedlessness of these 

new hybrids is based on self-incompatibility or male sterility, important problems should be encountered 

in areas where self-incompatible varieties such as the clementine are the predominant production. 

• Seedlessness and ploidy manipulation for triploid creation 

The selection of triploid lines is a very interesting way to develop seedless cultivars. Indeed triploidy is 

generally associated with both male and female sterility. Thus, most of the trees of a triploid progeny under 

field evaluation present these characters and an efficient selection can be carried out in other traits. 

Several methods have been developed for triploid citrus creation. One of them exploit natural events 

of polyploidization such as 2n gametes, using embryo rescue and flow cytometry to select triploids in 

2x X 2x crosses. The most classical strategy is to cross diploid non-apomictic females with tetraploid 

males. Such tetraploid plants can be found in apomictic seedlings (natural doubling of the chromosome 

stock of nucellar cells) or are created by somatic hybridisation. Tetraploid non-apomictic lines have been 

obtained by colchicine treatment of shoot tips grafted in vitro and, these tetraploids open the avenue to 

4x X 2x crosses with tetraploid female parent. As an example, in the Spanish mandarin triploid breeding 

program more that 15,500 triploids have been recovered using the three crossing strategies and using 

routinely in vitro embryo rescue and flow cytometry to determine the ploidy level of regenerated plants. 

In the last 10 years several new triploid cultivars resulting mostly from the oldest breeding strategy 

(diploid x autotetraploid sexual crosses) have been released in Italy, USA, and Japan, and some of these 

cultivars are now being produced for the market. Recently, four new triploid mandarin cultivars recovered 

after 2x x 2x crosses have been released in Spain. 


• Somatic hybridization 

Plant somatic hybridization via protoplast fusion has become an important tool for ploidy manipulation 

in plant improvement programs, allowing researchers to combine somatic cells from different cultivars, 

species, or genera, resulting in novel allotetraploid and autotetraploid genetic combinations. This 

technique can facilitate conventional breeding, gene transfer, and cultivar development by bypassing 

some problems associated with conventional sexual hybridization including sexual incompatibility, 

nucellar embryogenesis, and male or female sterility. The most important application of somatic 

hybridization in plant breeding programs is the building of novel germplasm as a source of elite breeding 

parents for various types of conventional crosses. In Citrus, somatic hybridization is being used to 

generate key allotetraploid breeding parents for use in interploid crosses to generate seedless triploids 

and for creation of new cybrids and asymmetric hybrids. Countries supporting programs based in this 

technology include USA, Brazil, Japan, China, France, Italy, Brazil, New Zealand and Spain. 

• Genomics 

Due to the generally important heterozygosity of genitors and long juvenile period, the development of 

markers for oriented introgression and early selection is a key point to improve the efficiency of citrus 

sexual breeding. Clementine haploid sequence is available (www.phytozome.net) and the clementine 

genetic map has been recently publicised. With these new tools citrus breeders will be able to survey 

and comprehend the citrus genetic diversity with the objective to assist and enhance breeding programs. 

• Genetic transformation 

Genetic transformation allows the introduction of specific traits into known elite genotypes without 

altering their genetic background. In the mandarin groups like clementines and satsumas, and due to 

their highly heterozygous and complex genetic structure, genetic transformation should be considered 

as a very promising tool for improvement despite of the negative social acceptance of these plants. 

Advantages and disadvantages of the different procedures for different breeding objectives will be discussed 

in the workshop, and also their relationship with the legislation related to essentially derived varieties, that 

in some cases may preclude the protection of breeder´s rights of new varieties. 

W03 

Procedures for the exploitation of protected and/or patented varieties 

Convener: Mercedes Iborra 

Norma Agrícola. Rafelbuñol, Valencia (Spain). E-mail: miborra@normagricola.com 

Since the early 19th century, the introduction of new varieties is an essential component to maintain and 

sustain good and high crop productivity and quality. New varieties are constantly being bred for higher yields, 

for better agronomic and quality traits like taste, and for resistance to abiotic and biotic stresses. 

Plant Breeders’ Rights (PBR), also called Plant Variety Protection (PVP), is an exclusive right granted to breeders 

of new varieties to exploit their varieties and has features that are in common with patents for industrial 

inventions. Both forms of protection grant to their holders a form of exclusive right to pursue innovative 

activity. With the PVP legislation, growers are in a better position to have access to new and improved varieties 

for commercial growing. 

Protection of a new variety is granted via a registration process based on validation of plant characteristics 

that distinguishes it from other varieties. The condition for registration of new plant varieties and the granting 

of breeder’s right is that the plant variety is new, distinct, uniform and stable. The scope of a breeder’s right 

extends to acts carried out on a commercial basis including producing or reproducing, conditioning for the 

purpose of propagation, offering for sale, marketing, exporting, importing and stocking the material for the 

earlier activities. Hence, unauthorized conduct of such acts will constitute an infringement under the law. 

Today practically all new citrus varieties are being protected, and their exploitation is being done following 

different models: 


• Open: All growers have free access after paying royalties (per plant or per surface, ie. ‘Pri23’, ‘Sunnyridge’). 

• Restricted: There is partial access to rights of exploitation by limiting the supply (by surface or by 

production, ie. ASF club) or by restricted markets (only a few destinations or on certain dates, ie. ‘Garbí’ 

or ‘Safor’ mandarins, so far restricted to the Spanish market). 

• Closed: No one has free access to the operating rights, except the company that has the rights in the 

country. (ie. ‘Orri’, ‘Unifrutti’ with ‘Regal’ seedless) or closed to producers who have made custom 

production (ie. ‘Zespri gold’). 

• Variety Club: There is no free access, as the right to development and commercialization has been 

delivered by the breeder to a closed group of farmers or propagating and exporting companies (ie. ‘M7’). 

In all cases it is very important to take additional precautions, control the varieties information (where they 

are grown), by producing it only within a given organization or granting licenses or contracts to trusted seed/ 

plants producers, enforce protection, stay alert for unauthorized sales, notify any individuals, companies, or 

other organizations that sell or distribute your variety. 

If the breeders, both public or private, have a good system to protect their PVP, it will be possible to get 

returns on their investments, which can then be used to develop the next round of improved varieties from 

their breeding programs. This implies that the use of new varieties is subject to the payment of royalties and 

involves the protection of the breeder’s rights and the variety value. Many breeders and master Licenses of 

the new varieties are not aware about control mechanisms, so have the risk of uncontrolled propagation of 

the variety and the loss of incomeIn all exploitation models, it is important to avoid irregular commercial 

exploitation in order to effectively protect plant breeders’ rights. The utilization of systems for planting 

geolocation has become a critical activity to identify the location and origin of the plantations that have 

cultivation rights (exploitation licenses), in order to minimize the incidence of illegal activity. It is also of 

significant importance to know the behavior of varieties in different geographical areas, with the aim of 

improving their knowledge. 

Some producers start to share once they have a protected variety, and a failure to control the spread has 

generated a mess. The main issue of piracy has a lot to do with auditing or genetic identification techniques, 

but also with ethical education in respecting IP. Major industry players are very concerned about the issue, 

and what would happen to their image if some competitors do not play by the rules. A solution to the 

problem could be the creation of clubs where businesses across the supply chain are identified to minimize 

risks, but not all varieties are suited to this form. Having the mapping of where the orchards are a profitable 

information. 

Visual NACert will be presented as an example of geolocation systems. It is an innovative, global information 

system designed initially for protected varieties management that operates through Internet. It easily 

identifies plantations in the earth’s surface and integrates modern technologies of visualization and data 

management into a single system. 

During the workshop the different exploitation models for protected varieties and control systems based in 

geolocation will be discussed. 

W04 

New perspectives in pest control 

Convener: Alberto Urbaneja 

Centro de Protección Vegetal y Biotecnología. Instituto Valenciano de Investigaciones Agrarias (IVIA). Moncada, Valencia (Spain) 

Co-conveners: J.A. Jacas 1 and P.A. Stansly 2 

1 Universitat Jaume I (Spain); jacas@uji.es. 2 University of Florida (USA); pstansly@ufl.edu. E-mail: aurbaneja@ivia.es 

Citrus is an international crop, accessible to exotic pests, but also with options to access solutions from around 

the world. The introduction to California of cottony cushion scale followed by the vedalia beetle in 1888, is 

just one early example of how citrus entomologists have worked together to develop ways to safeguard this 

important crop. Recent years have continued to see the spread of serious invasive pests and vectored diseases 

that challenge our scientific and grower communities. Climate change may also serve to exacerbate impacts 

from new invaders as well as resident pests. Current options to deal with these challenges are many, from 


-omic approaches to food-web engineering. The overall objective is to increase the sustainability of citrus 

while providing the public with a safe wholesome product that can be justifiably promoted for enhancement 

of human health. Strategies to be discussed for achieving this goal include: 

• Augmentative and conservation biological control 

Evergreen agro-ecosystems like citrus support complex food webs with diverse natural enemies that can 

be conserved and manipulated to maintain most pests below economic injury levels. Studies focused on 

the role of indigenous natural enemies in the citrus agrosystem and the conservation of both native and 

exotic natural enemies are being emphasized in recent years. Such studies and the management systems 

they lead to will probably continue to play more important role in the citrus production worldwide. 

• Selective chemistry 

While an important goal is decreased dependence on pesticides, not all pests can always be adequately 

controlled biologically. Selective “smart” chemistry that can selectively suppress difficult pests with 

minimal collateral damage to non-target organisms will continue to be important tools in the near term 

as the industry moves toward more sustainable management systems. 

• Semiochemical-based pest management 

Semiochemicals are the most selective of all chemicals and therefore the most compatible with biologically 

based management systems. New sex pheromones for monitoring, mass trapping and mating disruption 

are continually being made available and finding their place in citrus pest management. 

• Pest management based on citrus molecular biology 

The rapid development of molecular tools and techniques has led to major breakthroughs in entomology 

that impact agricultural production. These include use of molecular markers for the correct taxonomic 

identification of citrus invasive pests, the molecular gut-content analysis to identify food web interactions 

between predators and pests, and detection of resistance to insecticides in different citrus key pests. 

We can anticipate many new molecular advances, especially in the fields of comparative genomic 

and metabolomic analyses used for identifying and manipulating candidate pathways involved in the 

response of citrus to pests and vectored diseases. 

These and other new biorational approaches must be combined into functional systems adapted to diverse 

environmental conditions if current Integrated Pest Management (IPM) programs are to progress in the 

future. Researchers and IPM practitioners must remain current in order to better serve their clientele and 

also help inform the general public to better accept new and more sustainable technologies. Experts and 

practitioners of these and other pest management strategies are invited to present recent advances and join 

the discussion on ways to maintain citrus profitable and sustainable in the 21 st century. 

W05 

Dwarf citrus trees in high density plantings 

Convener: Kim D. Bowman 

U. S. Horticultural Research Laboratory. Fort Pierce, Florida (USA). Email: Kim.Bowman@ars.usda.gov 

Dwarf citrus trees have the potential to be used in high density plantings that will have greater yield during 

the first few years after tree establishment, and be easier to care for and harvest as the trees mature. Dwarf 

citrus may be obtained by management practices that restrict growth of standard cultivars or by genetic 

dwarfing traits of the scion, interstock, or rootstock. In this workshop, detailed information will be presented 

on the characteristics of two new USDA-ARS size-controlling rootstocks, considerations in the design and 

management of high density plantings with dwarfing rootstocks, and the trends in commercial use in Florida. 

The workshop will also include an overview of rootstock effects on tree size, the potential for producing dwarf 

citrus trees through the use of a dwarf scion, and management techniques that could be used to restrict tree 

growth and thus produce dwarf trees for use in high density plantings. Additional information on dwarf citrus 

and high density plantings will be presented by workshop attendees. The challenges and benefits associated 

with dwarf citrus trees in high density plantings will be discussed. 


Genetic restriction of fruit tree size is most commonly obtained by using a size-controlling rootstock. The most 

widely recognized citrus size-controlling rootstock is ‘Flying Dragon’ trifoliate orange (Poncirus trifoliata), and this 

rootstock is currently used to a limited extent in many citrus growing areas to establish high density plantings. 

Genetic transmission of the dwarfing trait to progeny of ‘Flying Dragon’ has been reported, and many hybrids 

have been produced and tested. Two hybrids of mandarin with ‘Flying Dragon’ have been released by USDA- 

ARS for commercial use in Florida over the last five years. US-897, a hybrid of Citrus reticulata ‘Cleopatra’ × 

‘Flying Dragon’, was released by USDA in 2007. This rootstock combines the induction of dwarfing on the grafted 

scion, along with the induction of good fruit production and fruit quality, and good resistance to several disease 

problems, including citrus tristeza virus (CTV) and tolerance to the Phytophthora-Diaprepes weevil complex 

(PDC). Tree size obtained with ‘US-897’ rootstock varies by scion and tree age, but in one typical trial with 

‘Hamlin’ sweet orange (Citrus sinensis) scion, 16-year-old trees on ‘US-897’ were 3 meters tall, while those on 

standard size rootstocks were 5-7 meters tall. ‘US-942’ is a hybrid of Citrus reticulata ‘Sunki’ × ‘Flying Dragon’ 

and was released by USDA-ARS for commercial use in 2010. ‘US-942’ also produces a grafted tree that is highly 

productive of good quality fruit and resistant to CTV and PDC. Trees with sweet orange scion on ‘US-942’ vary in 

size by cultivar, but tree volumes on ‘US-942’ are typically 65-85% that of trees on standard-size rootstocks, like 

‘Carrizo’ citrange. In the year ending summer of 2012, official propagations in Florida were listed as 73,220 trees 

on ‘US-897’ rootstock and 38,489 trees on ‘US-942’. 

This workshop will provide researchers the opportunity to present information about size-controlling 

rootstocks and other approaches to developing dwarf trees, as well as other studies related to development 

and management of high density plantings. The challenges and benefits associated with dwarf citrus trees in 

high density plantings will be discussed. 

W06 

Molecular identification of varieties 

Convener: Tokurou Shimizu 

NARO Institute of Fruit Tree Science (NIFTS), Citrus Research, Shizuoka (Japan). E-mail: tshimizu@affrc.go.jp 

Varieties of genus Citrus and its relatives show large diversity on their appearance and physiological 

characteristics, but some of them often look similar and are difficult to distinguish from others. Molecular 

identification of citrus varieties is beneficial to distinguish from similar ones by eliminating to depend on 

unstable morphological dissimilarity or empiricism. Genotyping analysis by DNA marker has been used for its 

accuracy, reliability, and reproducibility by detecting differences of nucleotide sequence among varieties that 

is called nucleotide polymorphism. Type and frequency of nucleotide polymorphism at different loci observed 

at a set of varieties correlates to genetic distance of them. Scoring genotypes by multiple DNA markers is 

therefore useful to reveal identity of individual variety, and phylogenetic relationships among citrus varieties. 

Initial attempts for DNA-based markers analysis used random markers like RAPD or ISSR. These DNA markers 

were advantageous by revealing sufficient number of polymorphism with less cost and required no prior 

nucleotide sequence data. But those kinds of markers are not suited for genetic study since they are unstable 

and less informative dominant markers. Nowadays co-dominant type DNA markers that improved stability, 

reproducibility and transferability including simple sequence repeat (SSR), insertion/deletion (indels) or 

single nucleotide polymorphism (SNP) are used in studies of citrus. These DNA markers are sufficiently 

informative for detailed genetic analysis but require nucleotide sequences of target organisms to design 

them. EST sequences or BAC end sequences were initially applied to design these markers. Recent citrus 

genome sequencing analysis revealed many polymorphic nucleotide sequence loci, and it is facilitating DNA 

marker development. Further efforts for nucleotide sequencing of various citrus varieties in the future will 

increase genome-wide DNA markers and improve their availability. 

With the rapid advance of DNA marker development, molecular identification analysis becomes a common 

technique. It has been applied for phylogenetic study to understand origin and development of modern citrus 

varieties, and also used in citrus breeding program to discard hopeless seedlings. Meanwhile, strong demand 

to protect breeders’ right of patented variety has developed. DNA marker analysis contributes to determine 

violation in accordance with scientific evidence by authorities. Applications of DNA marker analysis now cover 


processed products of fruit for juice, canned fruit, dried fruit and succade, but special care must be taken to 

evaluate these samples. 

Although current DNA marker analysis can identify natural varieties or crossbred varieties, technical limitation 

still remains for assured identification of mutant-origin varieties that covers most of major citrus varieties 

including sweet orange, Satsuma, grapefruit, Clementine, and lemon. On the other hand, rapid development 

of high-throughput genotyping analysis utilizing accumulated genome sequence information will allow 

distinguishing varieties of mutant origin in future. Besides potential of DNA marker analysis, DNA sample 

preparation method, cost, equipment or data analysis as well as number or type of DNA marker are still 

practically important points to be considered for each purpose. 

In this workshop, current status of DNA marker analysis and typical applications will be introduced. Feasibility 

of the technology and possible constraint for future challenge are the issues to be discussed. Setting up 

‘standard’ protocol of genotyping analysis and putting genotypes of patented varieties to public database 

is another valuable issue to discuss. Sharing these points among scientists, administrative agency and 

commercial growers would contribute for concerted development of scientific study and citrus industry. 

W07 

Mechanization of citrus harvest 

Convener: Enrique Moltó 

Centro de Agroingenieria. nstituto Valenciano de Investigaciones Agrarias (IVIA). Moncada, Valencia (Spain). E-mail: molto_enr@gva.es 

Co-convener: Reza Ehsani 

UF, Florida, US 

In most parts of the world, citrus are currently manually harvested, loaded in boxes and transported to 

packing houses or to processing facilities where fruit needs some kind of sorting. Although there are two 

clearly differentiated ways of cultivating citrus: for the fresh and for the processed market, in both cases 

manual harvesting accounts for the most part of the total production costs, with a high net share in the final 

price of the product. This situation has lead to major producing countries to invest in developing methods 

for mechanical mass harvesting. Moreover, the use of abscission agents for improving the performance of 

harvesting machines has been under research for more than a decade. 

This workshop is aimed at sharing with the audience the state of the art in mechanical harvest of citrus 

around the World and discussing about the efficiency, adaptability and socio-economic implications of the 

proposed solutions, including: 

• A historical review of engineering approaches to mechanical harvesting of citrus in Florida, where the 

most relevant efforts for mechanization of citrus for juice have been made since the 50’s. 

• Trunk shakers and fruit catchers experiences in Spain for harvesting fruits for the fresh market. 

• Historical attempts for robotic harvesting and current solutions for in-field sorting of fruit during 

harvesting in order to reduce packing costs. Limited energy and space availability are always critical 

issues for the electronic and mechanical designs of these machines. 

• The effect of mechanical harvesting on tree stresses and production in the subsequent years. 

• The advantages and disadvantages of the use of chemical abscission agents for facilitating the mechanical 

operation. 

• Needs and solutions for debris removal after mechanical harvesting. 

After a series of presentations by key researchers in these topics [(J. Syvertsen (UF), T. Spann (UF), J. Burns 

(UF), A. Torregrosa (UPV, Spain)], the participants in the workshop will have the opportunity to participate in 

an open discussion about these and any other matters related to de development of harvesting machines for 

the citrus industry. 


W08 

Global citrus industry collaboration on MRL regulatory issues 

Convener: James R. Cranney, Jr. 

California Citrus Quality Council. Auburn, CA (USA). Email: jcranney@CalCitrusQuality.org 

A significant number of citrus producers depend on exports as a critical part of their export marketing 

programs. Conversely, citrus fruits are not domestically produced in countries that represent a significant 

portion of the global population, so in those countries, citrus fruits must be imported. As a result, global trade 

of citrus fruits has become a high priority for citrus producers and consumers. 

While the demand for citrus fruits may be great, no fruit can be exported unless it meets the pesticide residue 

regulatory standards of the importing country. As the global citrus trade has become more important, 

there has been a steady increase in the regulation of pesticide residues on traded citrus commodities. With 

increasing global demand for citrus fruits and greater regulation, the need for more pesticide maximum 

residue levels (MRLs) for citrus has never been greater. 

This workshop will explore the possibility that citrus producers around the globe could work collaboratively 

to advocate for more citrus MRLs and for global regulatory policies that benefit citrus producers and trade. 

The goal of the workshop is to generate coordinated activity among citrus industry leaders to facilitate more 

global citrus trade. 

An overview of technical and regulatory issues under consideration within the Codex Committee on Pesticide 

Residues and report on the outcome of the Global Minor Use Summit will be presented. 

Within the discussions in this workshop we hope to identify common pesticide-related problems of citrus 

exporters and country-specific leaders willing to advocate for change in regulatory policies. Problems and 

solutions could be regional or global in nature. Citrus growers, trade association leaders, exporters and 

packers are encouraged to attend this organizational meeting. 

W09 

Global conservation strategy for citrus genetic resources 

Convener: Kim Hummer 

USDA ARS National Clonal Germplasm Repository. Corvallis, Oregon (USA). Kim.Hummer@ARS.USDA.GOV 

Co-conveners: Mikeal Roose1 , Fred Gmitter2 and Richard Lee3 1 Department of Botany and Plant Sciences, University of California. Riverside, CA (USA); 2 University of Florida, Citrus Research and 

Education Center. Lake Alfred, FL (USA); 3 USDA-ARS National Clonal Germplasm Repository for Citrus and Dates. Riverside, CA (USA). 

mikeal.roose@ucr.edu; fgg@crec.ifas.ufl.edu; Richard.Lee@ARS.USDA.GOV 

Citrus is an important world tree fruit crop with production in more than 146 countries. The center of origin 

for citrus is considered to be Southeastern Asia including southern China, northeastern India, and Malaysia, 

with secondary centers in surrounding areas. Novel and commercially significant scion and rootstock cultivars 

originating by natural mutation or directed hybridization were introduced during the past century. Significant 

genetic resource collections exist in many countries. A global citrus germplasm network was developed in 

1997. Now that the International Treaty on Plant Genetic Resources for Food and Agriculture (ITPGR) has 

recognized Citrus as an Annex 1 crop, a global conservation strategy needs to be established. The objective 

of this workshop is to plan the development of this strategy. A statement reviewing germplasm exploration 

and collection gaps needs to be updated. A survey of Citrus ex situ genebanks will define specific protocols. 

Alternative conservation strategies such as cryogenic approaches will be included. Global disease and pest 

pressure need to be summarized. A statement detailing protocols for safe movement of germplasm needs 

to be updated. The success of this strategy will provide a granting opportunity where ex situ genebanks 

could be supported to improve conservation and health of critical Citrus germplasm of global significance. 

Participation of all interested parties in this workshop is encouraged. 


W10 

Citrus and health 


CEBAS-CSIC. Murcia (Spain). Email: fatomas@cebas.csic.es 

The effect of citrus fruits in human health has been an active field of research particularly during the last 

twenty years. This activity has been associated with benefits for cardiovascular and bone health, and with 

the decrease of cancer risk. Many of these studies have used in vitro models that do not reflect the complex 

situation in vivo. Clinical studies, however, have shown large inter-individual variability, leading to nonsignificant 

effects in many cases. The recent advances in the knowledge of citrus bioactives metabolism and 

bioavailability, and in human nutrigenetics, and gut microbiome open great expectations to understand the 

effects of citrus phytochemicals on health. In this workshop the research strategies, trends and perspectives, 

to support the role of citrus fruits in human health will be discussed. 

Are the in vitro studies valid to demonstrate citrus health effects? 

Many mechanistic studies use human cell cultures to evaluate the biological effect of citrus extracts, or 

isolated bioactives from citrus, and these studies are often extrapolated to the potential effects in vivo. Most 

of these studies, however, have some mayor flaws, although they can be published in very good scientific 

journals, although they usually do not correlate with the effects observed in vivo. The main problems found 

are associated with the dose, the chemical nature of the citrus bioactive tested and the human tissue used 

in the assay. The dose used is often much higher than the amounts found in vivo, and these high doses are 

necessary to see a relevant effect. The long term approach, using low metabolite concentration or mixtures 

of them, which is the situation found in vivo, is difficult to evaluate with the classical models. The type of 

metabolite used in the assays is often that found in the food products, although these compounds are 

metabolized but the gut microbiota and the human Phase II enzymes to produce metabolites that differ 

from those found in citrus fruits. In addition, the tissue model used is often inappropriate for the metabolites 

tested as many of these metabolites do not reach the tissues that are assayed for the effects. Therefore, a 

new scientific approach is needed to evaluate the mechanisms of action using the appropriate cell lines, with 

the appropriate metabolites and at the concentrations that reach the specific tissues, and providing systems 

that mimic the long term effects that are found in vivo. 

Can we explain the large inter-individual variability observed in clinical studies? 

In clinical studies with citrus fruits and extracts, a large inter-individual variability is generally observed with 

individuals that respond to the intervention with relevant biological effects, while other individuals do not 

respond to the intervention in the same way. This behavior could be explained by differences in the genetic 

background of the individuals (nutrigenetics, transporters, metabolic enzymes isoforms, etc.), by differences 

in the metabolism of the bioactive compounds by the colon microbiota, or by a combination of both factors. 

The relevance of these two factors in the evaluation of the health effects of citrus products will be discussed, 

and the need of stratification of the population used in the studies to explain the results obtained will be 

presented. 

W11 

Quarantine security for Tephritid fruit flies pests in citrus 

Convener: N. J. Liquido 

USDA-APHIS-PPQ, Center for Plant Health, Science and Technology, Plant Epidemiology and Risk Analysis Laboratory. Honolulu, Hawaii 

(USA). Email: Nicanor.J.Liquido@aphis.usda.gov 

Co-convener: R.L. Griffin 

USDA-APHIS-PPQ, Center for Plant Health, Science and Technology, Plant Epidemiology and Risk Analysis Laboratory. Raleigh, North 

Carolina (USA). Email: Robert.L.Griffin@aphis.usda.gov 

Tephritid fruit flies are serious pests of citrus. They cause direct fruit damage through oviposition and larval 

feeding, and warrant regulatory restriction on the movement of citrus fruits across national and international 

boundaries. Current quarantine mitigations for fruit flies in citrus include fumigation, high-temperature 


forced-air, vapor heat, cold, and irradiation treatments. Cold treatment appears to be a treatment of choice 

by several citrus producing countries, with a multitude of schedules and combinations of low temperature 

and treatment duration, depending on species of citrus and the guild of associated fruit fly pests. 

Participants are encouraged to join the discussion on evaluating current quarantine treatment schedules and 

exploring measures of achieving quarantine security other than Probit 9, including possibilities of integrating 

less than probit 9 treatments in developing systems approaches to mitigate risk of fruit fly pests. 

Probit analysis is a statistical method for determining a dose-response relationship and calculating the 

appropriate dose for a specific response. The probit 9 mortality response estimates 32 survivors, or less, from 

1,000,000 treated pest individuals. At the 95% level of confidence, the probit 9 statistics predicts no survivors 

in a minimum of 93,613 test insects. 

The probit 9 efficacy (99.9968% desired response, e.g., mortality) is the unofficial obligatory de facto standard 

of treatment efficacy for high risk pests in highly susceptible hosts adapted by the United States and many 

countries. For naturally poor hosts, the probit 9 standard may be too rigid and impractical, and treatment 

efficacy lower than probit 9 may be sufficient to achieve the desired quarantine security. In the alternative 

treatment efficacy approach, risk may be defined either as the number of survivors or as the probability 

of a mating pair being present in a shipment, rather than as the effective mortality of the treated infesting 

individuals. 

The less than probit 9 approach has regulatory recognition and acceptance. Japan, Australia, and New Zealand 

accept quarantine treatment efficacy at 99.99%. Furthermore, 99.99% mortality, or survivorship of 0.0001, is 

the experimental benchmark for verifying the conditional non-host status of a fruit or vegetable commodity 

to a fruit fly pest. The 99.99% mortality at the 95% confidence level is approximately probit 8.72. 

Probit 9 treatments are mandated in many situations without regard to rates of natural infestation; 

gregariousness (single versus multiple infestation); survival and reproductive capacity of the pest; inherent 

hardiness of the pest to environmental stress during packaging and shipment; seasonality of shipment; 

distribution of the commodity in the importing country; and other biological and nonbiological parameters. 

However, risk managers are familiar with them; a number of precedent-setting probit 9 treatments have 

been established based on accords during bilateral agreement to facilitate trade, with scientific justification 

possibly from liberal extrapolation of meager technical data. 

Thus, a discussion of these approaches is needed to effectively mitigate the risk of fruit fly pests for a specific 

host commodity and the infesting pest of interest. 


Session 01 

CITRUS GERMPLASM 

AND PHYLOGENETICS 

S01

S01O01 

Citron germplasm in Yunnan, China 

Karp D. 1 , Krueger R.R. 2 , Kahn T. 1 , and Hu X. 1 

1 University of California, Riverside (UCR), Department of Botany and Plant Sciences, United States; and 2 United States Department 

of Agriculture, Agricultural Research Service (USDA-ARS), National Clonal Germplasm Repository for Citrus and Dates, United States. 

dkarp@ucr.edu 

The center of origin and diversity for citron (Citrus medica) is Southwestern China, Northeastern India, and 

adjacent regions of Southeast Asia, but very little is known about citron germplasm resources in this area. Citron 

germplasm resources are rapidly being eroded as forests are cleared for development and farmers abandon 

citron cultivation for more profitable crops. Starting in 2008, researchers for the Chinese Citron Germplasm 

Project travelled around Yunnan and other provinces of China, observing both cultivated and wild citron. We 

collected information about germplasm, horticultural practices, and economic uses, as well as cuttings and 

seeds, which were used to establish a germplasm collection with 30 accessions in Jianshui, Yunnan. Wild citrons 

typically have smaller fruits and thinner rinds than commercial cultivars; it is likely that over the centuries 

farmers have selected for a thick rind, as the most economically valuable part, for preserving and eating fresh. 

The majority of common (non-fingered) citrons grown in Yunnan have thick, sweet albedos, but no juice 

vesicles. Some grow as large as 15 kg, making them the largest known citrus fruits. Common citron cultivars 

include ‘Large Wrinkled’, ‘Small Wrinkled’, ‘Pillow’, ‘Sour’, ‘Water’, ‘Dog Head’, ‘Bullet’, ‘Yunnanensis’, ‘Oblate’, 

and ‘Stigma Persistens’. Fingered (Buddha’s Hand) citrons are grown primarily as ornamental plants and to be 

dried for use in Chinese Traditional Medicine, but also for candying. Many distinct cultivars exist, which vary in 

flower color, size, thickness of fingers, and the point at which the fingers branch out from the body of the fruit. 

Fruit types of fingered citron include the common, ‘Octopus’, ‘Fist’, and ‘Half-and-Half’. There is also a cultivar 

native to southern Sichuan, ‘Muli’ citron, which is intermediate between fingered and common citron. 

S01O02 

Cryopreservation of citrus for long-term conservation 

Volk G.M., Bonnart R., Shepherd A., Krueger R.R., and Lee R.F. 

United States Department of Agriculture, Agricultural Research Service (USDA-ARS), National Clonal Germplasm Repository for Citrus 

and Dates, United States. gvolk@lamar.colostate.edu 

More than 850 varieties of Citrus, Fortunella, and Citrus-related species are maintained within the USDA-ARS 

National Plant Germplasm System and the University of California Citrus Variety Collection. These genetic 

resources are held within duplicated field, screenhouse, and greenhouse collections. Plant materials are at 

risk of disease infestations, abiotic stresses, and natural disasters. We have developed a cryopreservation 

method by which we can back-up citrus genetic resources for the long term at liquid nitrogen temperatures. 

We excise shoot tips directly from greenhouse or screenhouse source plants, surface sterilize, and then treat 

with cryoprotectants. These solutions dehydrate and allow the shoot tips to survive liquid nitrogen exposure. 

Plants are recovered by micrografting thawed shoot tips onto ‘Carrizo’ seedling rootstocks. Plants representing 

diverse species exhibit a high regrowth (more than 50%), and can be transferred to greenhouse conditions 

within months. Cryopreserved plants did not revert to a juvenile state. Accessions of Citrus aurantifolia, Citrus 

clementina, Citrus celebica, and Citrus paradisi all flowered within 13 to 15 months after cryoexposure. These 

methods are also applicable for disease eradication using cryotherapy techniques. 

S01O03 

Genetic diversity and population structure of the mandarin germplasm revealed by nuclear and 

mitochondrial markers analysis 

Garcia-Lor A. 1 , Luro F. 2 , Ancillo G. 1 , Ollitrault P. 3 , and Navarro L. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Proteccion Vegetal Y Biotecnología, Spain; 2 Institut National de 

la Recherche Agronomique (INRA), Unité de recherche GEQA, France; and 3 Centre de coopération Internationale en Recherche 

Agronomique pour le Développement (CIRAD), BIOS, France. angarcia@ivia.es 

Mandarins (C. reticulata) are considered as one of the four main species involved in the origin of cultivated citrus. 

However, the classification of the mandarin germplasm is still controversial and numerous cases of introgression 

from other species are known or suspected in this germplasm. The main objective of this work was to analyze 

the genetic diversity structure of mandarin germplasm and its relationship with the other citrus species. Fifty 

XII INTERNATIONAL CITRUS CONGRESS 2012 - 27 

S01

S01 

microsatellite (SSR) markers, 25 Insertion-Deletion (InDel) nuclear markers and four mitochondrial InDel markers 

were genotyped for 223 accessions. ‘Structure’ software was applied on nuclear data to check and quantify 

potential interspecific introgressions in the mandarin germplasm, mainly the pummelo and papeda genomes. 

Within the mandarin germplasm without identified introgression, seven clusters were revealed by ‘Structure’ 

analysis. Five of them should be true basic mandarin groups and the other two include genotypes of known or 

supposed hybrid origin. The contributions of these seven groups to the mandarin genotypes were estimated. 

The mitochondrial InDel analysis revealed eight mitotypes, in which the mandarin germplasm was represented 

in four of them. In this work, new insights in the organization of mandarin germplasm and its structure have 

been found, and different mandarin core collections were determined. This will allow a better management and 

use of citrus germplasm collections and to perform genetic association studies. 

S01O04 

Study on genetic diversity of 39 Citron germplasm resources with SCoT and ISSR markers 

Shu-wei Z., Gui-Xiang H., Xin-Hua H., Jie-Chun P., and Feng D. 

Agricultural College of Guangxi University, P.R.China. honest66222@163.com 

The genetic relationships and diversity of 39 citron (Citrus medica) germplasm resources were examined by 

SCoT and ISSR markers in this study. Of the 80 SCoT primers screened, 9 primers gave reproducible, polymorphic 

DNA amplification patterns with a total 69 amplified bands. The polymorphic percentage was 76.8%. Of the 

100 ISSR primers screened, 9 primers gave reproducible, polymorphic DNA amplification patterns with a total 

84 of amplified bands. The percentage of polymorphic band was 77.4%. An UPGMA relationship tree was 

established based on the similarity coefficients. At the coefficient level of 0. 85 for SCoT and 0.77 for ISSR, the 

39 germplasm resources were divided into six groups and five groups, respectively. The application of SCoT 

and ISSR markers is discussed in this paper. 

S01O05 

Origin of dwarf, thornless-type trifoliate orange varieties deduced from genome-wide 

genotyping analysis 

Shimizu T., Yoshioka T., Kita M., and Ohta S. 

NARO Institute of Fruit Tree Science (NIFTS), Citrus Research, Japan. tshimizu@affrc.go.jp 

Trifoliate orange (Poncirus trifoliata) is commonly used as a rootstock in Japan. Several varieties that are different 

for tree height or tree morphology are recognized. However, origin and phylogenetic relationship among them are 

not evaluated. We compared genotypes of three varieties, a thornless type trifoliate orange that lacks thorns at 

the leaf axil and two dwarf types, ‘Hiryu’ (‘Flying dragon’) and ‘Unryu’ (‘Cloudy dragon’), to a reference accession 

of trifoliate orange in our citrus collection. Genotyping analysis with 289 genome wide SSR markers gave 265 valid 

genotypes. Among them, ‘Hiryu’ lost five loci but 96.2% of genotypes were matched to those of the reference. In 

contrast, the thornless-type lost 4 loci and 78.8% of genotypes were matched to those of the reference, and ‘Unryu’ 

lost 6 loci and 81.4% of genotypes were matched to those of wild type. Assignment of SSR marker genotypes to 

a citrus linkage map revealed that genotypes of ‘Hiryu’ were well conserved among all linkage groups. However, 

loss of heterozygosity (LOH) was observed at various regions of linkage groups for the thornless-type and ‘Unryu’. 

Ratios of homozygous loci of the reference, the thornless-type, ‘Hiryu’ and ‘Unryu’ were 70.3%, 88.5%, 69.1%, and 

84.9%, respectively. These observations suggested that ‘Hiryu’ is a sport of trifoliate orange but the thornless-type 

and ‘Unryu’ resulted from trifoliate orange by self-pollination and mutation at particular loci. 

S01O06 

Multilocus haplotyping by parallel sequencing to decipher the interspecific mosaic genome 

structure of cultivated citrus 

Curk F. 1 , Ancillo G. 2 , Garcia-Lor A. 2 , Luro F. 1 , Navarro L. 2 , and Ollitrault P. 3 

1 INRA, UR1103 Génétique et Ecophysiologie de la Qualité des Agrumes (INRA UR GEQA), France; 2 Instituto Valenciano de Investigaciones 

Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; and 3 Centre de Coopération International en Recherche Agronomique 

pour le Développement (CIRAD), BIOS, France. curk@corse.inra.fr 

Recent studies support the theory that four basic taxa (Citrus medica, Citrus maxima, Citrus reticulata and Citrus 

micrantha) have generated all cultivated Citrus species. It is supposed that the genomes of most of the actual 


citrus cultivars are interspecific mosaics of large DNA fragments issued from a limited number of interspecific 

meiotic events. In the present work, we analyzed how haplotypic multilocus study of closely linked SNPs 

allows phylogenetic assignment of DNA fragments for the main cultivated species. We have developed a new 

method based on universal primers to prepare the amplicons to be analyzed by 454 technology (Roche). It 

was applied for direct multilocus haplotyping of 12 gene fragments of 48 Citrus genotypes. Moreover, Sanger 

sequencing was performed on a subset of these amplicons (seven gene fragments of 24 citrus genotypes) to 

validate the 454 results. Consensus haplotype sequences were successfully identified from 454 sequencing. 

Sanger and 454 results were mostly identical. C. reticulata was the most polymorphic basic taxa. The average 

differentiation between the basic taxa was about 20 SNPs/kb. These polymorphisms were enough for 

unambiguous multilocus differentiation of the basic species and assignment of phylogenetic origin for each 

haplotype of the secondary species. Multilocus haplotyping by parallel sequencing will be a powerful tool to 

decipher the interspecific mosaic genome structure of cultivated citrus. 

S01P01 

Citrus ichangensis in Sichuan and Chongqing 

Zhang Y., and Zhou X. 

Citrus Experiment Station of the Middle Reaches of the Yangtze River, Chongqing Academy of Agricultural Sciences, P. R. China. 

zhangyg66@gmail.com 

Citrus ichangensis from Sichuan and Chongqing Provinces occurs in a wild state in the hills of 42 counties, 

growing at altitudes of 800 to 2400m with soil pH 5 to 6.5. The dominant vegetation around this species 

consists of pine, Chimonobambusa utilis, plum, kiwifruit, wild cherry, pear, waxberry, fern, rhododendron, 

couch grass, et cetera. The typical C. ichangensis is a shrub or tree, usually 1 to 8 meters high; the corolla of 

the flowers is purple, light purple, or white; the fruits are ellipsoid, obloid, spheroid or pyriform, 36 to 170 

g in weight; the seeds are very large, very numerous (from 20 to 67 in a single fruit), and monoembryonic. 

S01P02 

Diverse genetic resources of citrus in North-East region of India 

Huidrom S.D. 1 , Singh S.R. 1 , and Handique P.J. 2 

1 Institute of Bioresources and Sustainable Development (IBSD), Dept. of Biotechnology, Govt. of India., India; and 2 Gauhati University 

(GU), Department of Biotechnology, India. huidrom_sunitibala@rediffmail.com 

The diverse gene pool of citrus in the North-East India is represented by 23 species, a subspecies, and 

68 varieties. Collection, conservation and characterization are necessary for incorporating the useful 

agronomically important traits present in this large gene pool for breeding of improved citrus rootstocks and 

cultivars and exploring bioactive compounds present in them. Twenty eight accessions of citrus belonging 

to different species have been collected and morphologically characterized. Variability observed among the 

citrus accessions collected is reflected by five different types of fruit shape, five different types of fruit base 

shape, four different types of fruit apex shape, four types of leaf lamina shape, three different types of petiole 

wing shape, three types of leaf apex, four different types of leaf margin, two types of leaf lamina attachment 

and five different types of seed shape. Citrus accessions collected have fruit color ranging from light yellow 

to yellow and orange to orange red color. Various forms of citrus types such as pummelos, citron, acid lime 

and other hybrids are available in cultivated, semi-cultivated and wild forms which required immediate 

intervention of a scientific way of conservation to prevent the continuing threat of genetic erosion. 

S01P03 

Observations of graft compatibility between Citrus spp and related Aurantioideae taxa 

Siebert T. 1 , Kahn T. 1 , and Krueger R.R. 2 

1 University of California, Riverside (UCR), Botany and Plant Science, United States; and 2 USDA-ARS National Clonal Germplasm 

Repository, United States. tsiebert@ucr.edu 

Although Citrus has long been known to be graft compatible with the genus Poncirus, compatibility between 

Citrus and other genera of the Aurantioideae is less well characterized. Graft compatibility between 


S01

S01 

Aurantioideae genera has historically been associated with the use of the related taxa as rootstocks for Citrus 

spp. However, the use of Citrus spp as rootstocks for related taxa can be useful in maintaining germplasm 

accessions, in propagating specimen trees or specific commercial taxa, and biological indexing in a sanitation 

program. One of the largest collections of taxa related to Citrus is maintained by the University of California 

and the United States Department of Agriculture in Riverside, California. This paper reviews historical 

observations made in Riverside of graft compatibility between Aurantioideae genera and updates them with 

current observations. Specific combinations have been observed to be incompatible whereas others have 

shown either short- or long-term compatibility and survival. 

S01P04 

Fertility relationships among Citrus and its relatives in the subfamily Aurantioideae 

Siebert T., Ellstrand N., and Kahn T. 

University of California, Riverside, Botany and Plant Science, United States. tsiebert@ucr.edu 

Data on fertility relationships between crop species and their relatives is of immediate practical value because 

they can be used to predict the ease of introgression of valuable traits into cultivars. Likewise, those data 

are of evolutionary significance as evidence of phylogenetic relationships. Here, we review what is known 

regarding the relative cross-compatibility of various Citrus taxa with each other as well as with members 

of other genera in the Rutaceae subfamily Aurantioideae. For the most part these data were collected as 

collateral information from breeding studies and therefore are uneven within the group. We compare how 

the extant fertility relationship data support the various molecular phylogenies of the Aurantioideae. We 

conclude with the identification of significant gaps in the data that could be filled with a series of strategic and 

feasible crosses for the purposes of better defining the systematic relationships of the group as well as guiding 

future citrus improvement by breeding. 

S01P05 

Characterization of seed and embryo abortion during fruit development in several citrus cultivars 

pollinated by ‘Nishiuchi Konatsu’ (Citrus tamurana) and preliminary trial of embryo rescue of 

aborting embryos 

Honsho C. 1 , Tsuruta K. 1 , Ryuto K. 1 , Sakata A. 1 , Kuroki S. 2 , Nishiwaki A. 2 , and Tetsumura T. 1 

1 University of Miyazaki, Faculty of Agriculture, Japan; and 2 University of Miyazaki, Field Science Center, Japan. 

chitose@cc.miyazaki-u.ac.jp 

‘Hyuganatsu’ (HY; Citrus tamurana) is a late-season citrus grown in several specific prefectures in Japan. 

Although it is self-incompatible, its bud mutation, ‘Nishiuchi Konatsu’ (NK), is self-compatible, and interestingly 

most of the seeds in harvested fruits are aborted. In our previous study we revealed that NK produces a 

proportion of unreduced 2N pollen grains, resulting in unusual seed development. In this study, we have 

focused on seed and embryo development when pollen from NK was used to pollinate HY, NK, and ‘Hassaku’ 

(HS; Citrus hassaku), which is compatible with both HY and NK. When NK pollen was used to pollinate HY or 

NK, most of the seeds aborted, whereas all seeds developed successfully from crossing using HS pollen. The 

seeds from NK-pollinated fruits were found to be significantly smaller than those from HS-pollinated fruits 10- 

12 weeks after pollination during periodic samplings of fruits, suggesting that the seed abortion phenotype 

is expressed during this time period. Embryo development was observed using differential interference 

contrast or stereo microscopy. Embryos that had formed from NK self-pollination had aborted at 10 weeks 

after pollination, whereas control embryos had reached the globular or heart-shaped stage. In the cross HS 

× NK, both normal and aborted seeds were present in the resulting fruit. Embryo development was found to 

cease at 12 weeks after pollination, and at 14 weeks after pollination, normal and aborted seeds were easily 

distinguishable. In addition to the characterization of seed development, preliminary attempts at embryo 

rescue have been made to recover triploid seedlings. After making the crosses HY × NK or NK × NK, aborting 

embryos were placed on MT media supplemented with 500 mg/L malt extract, 50 g/L sucrose, and 5 mM 

GA3. As a result, several triploid plantlets confirmed by flow cytometry were recovered from both pollination 

combinations, although the success rate was not high. 


S01P06 

Diversity analysis of citrus fruit pulp acidity and sweetness: toward to understand the genetic 

control of the fruit quality parameters 

Luro F., Gatto J., Costantino G., and Pailly O. 

Unité de Recherche 03 Génétique et Ecophysiologie de la Qualité des Agrumes (GEQA), Station de Recherche INRA, France. 

costantino@corse.inra.fr 

Acidity level is the main criteria of quality and physiological maturity evaluation for citrus fruit, especially 

for mandarins and oranges. The acidity level varies during fruit development but also among species and 

varieties, and also depends upon rootstock and environmental factors such as temperature and rainfall. Acid 

metabolism is linked to sugar metabolism. To better control fruit maturity and harvest time, it is necessary 

to understand the genetic control and the parameters influencing the variation of acidity and sweetness. 

Citrus diversity was investigated by selecting 87 varieties belonging to the 8 major Citrus species grown 

under the same environmental and cultivation conditions. The juice acidity and sweetness were analysed 

by assessing pH Na-neutralization and by refraction index, respectively, and their components by HPLC. 

The sequence polymorphisms of 9 candidate genes encoding for key enzymes of sugars and organic acids 

metabolic pathways were investigated by SSCP (Single Strand Conformation Polymorphism). Whatever the 

biochemical or molecular analysis, the observed structure of the Citrus diversity was organized around the 

ancestral species (mandarin, pummelo and citron). As expected, the secondary species were closely related 

to their putative species progenitors. The biochemical diversity was strongly correlated to molecular SSCP 

diversity without having any certainty on the cause and effect relationship. 

S01P07 

Screening a core collection of citrus genetic resources for resistance to Fusarium solani 

Krueger R.R. 1 , and Bender G.S. 2 

1 USDA-ARS National Clonal Germplasm Repository for Citrus & Dates (USDA-ARS-NCGRCD), USA; and 2 University of California 

Cooperative Extension, San Diego County (UCCE-SD), USA. robert.krueger@ars.usda.gov 

A causal agent for Dry Root Rot (DRR) of citrus has not been definitively identified, but the organism most 

consistently associated with DRR is Fusarium solani. To efficiently screen a citrus germplasm collection for 

resistance to F. solani, a core subset of the collection was evaluated. Seedlings of forty five accessions were 

wounded by girdling. Treatment consisted of inoculation with F. solani, with uninoculated controls. Three 

parameters were evaluated: recovery from girdling (0 - 3); amount of DRR (0 - 4); and percentage of healthy 

feeder roots. Thirty three accessions showed no significant difference in recovery from girdling between 

inoculated and uninoculated seedlings and 11 of these accessions showed good recovery from girdling (> 

2.7). Twenty four accessions showed no significant difference in DRR between inoculated and uninoculated 

seedlings, and 12 of these accessions showed low development of DRR (< 1). Twenty four accessions showed 

no significant difference in % healthy feeder roots between inoculated and uninoculated seedlings and 8 

of these showed a high percentage (> 80%) of healthy feeder roots. Five accessions were superior in all 

thee parameters: ‘Fremont’ mandarin (PI 539507), ‘Lamas’ lemon (PI 539226), ‘Mato Buntan’ pummelo 

(PI 529398), ‘Olivelands’ sour orange (PI 539164), and ‘South Coast Field Station’ citron (PI 539435). These 

accessions would probably represent the best candidates for further study of F. solani resistance. 

S01P08 

Nuclear phylogeny of Citrus and four related genera 

Garcia-Lor A. 1 , Curk F. 2 , Snoussi H. 3 , Morillon R. 4 , Ancillo G. 1 , Luro F. 2 , Navarro L. 1 , and Ollitrault P. 4 

1Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal Y Biotecnología, Spain; 2 INRA, UR1103 Génétique 

et Ecophysiologie de la Qualité des Agrumes (INRA UR GEQA), DGAP, France; 3Institut National de la Recherche Agronomique de 

Tunisie (INRAT), Laboratoire d’Horticulture, Tunisie; and 4Centre de coopération Internationale en Recherche Agronomique pour le 

Développement (CIRAD), BIOS, France. angarcia@ivia.es 

Despite considerable differences in morphology, the genera representing “true citrus fruit trees” are sexually 

compatible, but their phylogenetic relationships remain unclear. Most of the important commercial species 


S01

S01 

of Citrus are believed to be of interspecific origin. By studying SNP and InDel polymorphisms of 27 nuclear 

genes on 45 genotypes of Citrus and related taxa, the average molecular differentiation between species 

was estimated, and the phylogenetic relationship between “true citrus fruit trees” was clarified. A total of 

16238 bp of DNA was sequenced for each genotype, and 1097 SNPs and 50 InDels were identified. Nuclear 

phylogenetic analysis revealed that Citrus reticulata and Fortunella form a clade clearly differentiated from 

the other two basic taxa of cultivated citrus (Citrus maxima, Citrus medica). A few genes displayed positive 

selection patterns within or between species, but most of them displayed neutral patterns. The phylogenetic 

inheritance patterns of the analysed genes were inferred for commercial Citrus species. The SNPs and InDels 

identified are potentially very useful for the analysis of interspecific genetic structures. The nuclear phylogeny 

of Citrus and its sexually compatible relatives was consistent with their geographic origin. The positive 

selection observed for a few genes will orient further work to analyze the molecular basis of the variability of 

the associated traits. This study presents new insights into the origin of Citrus sinensis. 

S01P09 

New insights on limes and lemons origin from targeted nuclear gene sequencing and cytoplasmic 

markers genotyping 

Curk F. 1 , Garcia-Lor A. 2 , Snoussi H. 3 , Froelicher Y. 4 , Ancillo G. 2 , Navarro L. 2 , and Ollitrault P. 4 

1 INRA, UR1103 Génétique et Ecophysiologie de la Qualité des Agrumes (INRA UR GEQA), DGAP, France; 2 Instituto Valenciano de 

Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; 3 INRAT (Institut National de la Recherche 

Agronomique de Tunisie), Tunisia; and 4 Centre de Coopération International en Recherche Agronomique pour le Développement 

(CIRAD), BIOS, France. curk@corse.inra.fr 

It is believed that Citrus medica, Citrus maxima, Citrus reticulata and Citrus micrantha have generated all 

cultivated Citrus species. Depending on the classification, lemons and limes are classified either into two 

species, Citrus limon and Citrus aurantifolia (Swingle and Reece) or into more than 30 (Tanaka). In order to 

study the molecular phylogeny of this Citrus group, we analyzed 20 targeted sequenced nuclear genes and 

used 3 mitochondrial and 3 chloroplastic markers for 21 lemons and limes compared with representatives of 

the 4 basic taxa. We observed 3 main groups, each one derived from direct interspecific hybridizations: (1) 

the Mexican lime group (C. aurantifolia), including Citrus macrophylla, arising from hybridization between 

papeda (C. micrantha) and citron (C. medica); (2) the yellow lemon group (C. limon) that are hybrids between 

sour orange (Citrus aurantium, which is believed to be a hybrid between C. maxima and C. reticulata) and 

citron; and (3) a rootstock lemon/lime group (Rough lemon and Rangpur lime) that are hybrids between 

the acid small mandarin group and citron. We also identified different probable backcrosses and genotypes 

with more complex origins. None of the analyzed limes and lemons shared the C. medica cytoplasm, while 

this taxon is the common nuclear contributor of all limes and lemons. Limes and lemons appear to be a very 

complex citrus varietal group with the contribution of the 4 basic taxa. Neither the Swingle and Reece nor the 

Tanaka classifications fit with the genetic evidence. 

S01P10 

Diversity of citron (Citrus medica) and phylogenetic analysis of related citron hybrids using 

molecular markers and essential oil compositions 

Luro F. 1 , Venturini N. 2 , Costantino G. 1 , Tur I. 1 , Paolini J. 2 , Ollitrault P. 3 , and Costa J. 2 

1 Institut National de Recherche Agronomique (INRA), Génétique et Écophysiologie de la Qualité des Agrumes, France; 2 CNRS 

UMR 6134 (SPE), Laboratoire de Chimie des Produits Naturels, France; and 3 Centre de Coopération Internationale en Recherche 

Agronomique pour le Développement (CIRAD), AGAP, France. luro@corse.inra.fr 

It is commonly accepted that citron (Citrus medica) was the first citrus fruit to reach the Mediterranean 

area about 3 centuries B.C. The fragrance due to the essential oils is probably the main characteristic that 

has contributed to the reputation of this fruit in all Mediterranean countries for multiple uses including 

cosmetics, food, medicinal, ornamental and also as religious symbol. The Citron group is supposed genetically 

low diversified compared to mandarins and pummelos. To assess the diversity of the citron group we 

analyzed the molecular polymorphism of nuclear and cytoplasmic genetic markers and the variation in 

composition of essential oils from leaves and peels of 24 varieties of citron or apparent hybrids of citron. 


Our results demonstrate that the citron group has a relatively high allelic diversity, probably due to multiple 

introductions of several varieties. Self-fertilization was the mode of reproduction, which most frequently led 

to the development of commercial varieties with specific aromas and flavors such as the cultivar ‘Corsican’, 

a putative ‘Common Poncire’ self-crossed hybrid. However, some varieties appeared to be interspecific 

hybrids related to citron but only by male parent. This varietal diversity was probably favored by spreading 

seeds to extend the cultivation of citron in Mediterranean countries. The chemical diversity does not always 

correspond to genetic diversity but nevertheless reveals specific profiles for some genotypes. 

S01P11 

Analysis of genetic diversity in Tunisian citrus rootstocks 

Snoussi H. 1 , Duval M.F. 2 , Garcia-Lor A. 3 , Perrier X. 2 , Jacquemoud-Collet J.C. 2 , Navarro L. 3 , and Ollitrault P. 2 

1 Tunisian National Agronomic Research Institute (INRAT), Horticultural Laboratory, Tunisia; 2 International Center for of Agricultural 

Research for Development (CIRAD), Department BIOS. TGU. AGAP, France; and 3 Instituto Valenciano de Investigaciones Agrarias 

(IVIA), Centro de Protección Vegetal y Biotecnología, Spain. hagersnoussi@gmail.com 

Breeding and selection of new citrus rootstocks are nowadays of the utmost importance in the Mediterranean 

Basin because the citrus industry faces increasing biotic and abiotic constraints. In Tunisia, citrus contributes 

significantly to the national economy, and its extension is favored by natural conditions and economic 

considerations. Sour orange, the most widespread traditional rootstock of the Mediterranean area, is also the 

main one in Tunisia. In addition to sour orange, other citrus rootstocks well adapted to local environmental 

conditions are traditionally used and should be important genetic resources for breeding. Prior to initiation 

of any breeding program, the exploration of Tunisian citrus rootstock diversity was a priority. Two hundred 

and one local accessions belonging to four facultative apomictic species (Citrus aurantium, sour orange; Citrus 

sinensis, sweet orange; Citrus limon, lemon; and Citrus aurantifolia, lime) were collected and genotyped using 

20 nuclear SSR markers and four InDel mitochondrial markers. Sixteen distinct Multi-locus genotypes (MLGs) 

were identified and compared to references from French and Spanish collections. The differentiation of the four 

varietal groups was well-marked. Each group displayed a relatively high allelic diversity, primarily due to very high 

heterozygosity. The Tunisian citrus rootstock genetic diversity is predominantly due to high heterozygosity and 

differentiation between the four varietal groups. The phenotypic diversity within the varietal groups has resulted 

from multiple introductions, somatic mutations and rare sexual recombination events. This diversity study 

enabled the identification of a core sample of accessions for further physiological and agronomic evaluations. 

These core accessions will be integrated into citrus rootstock breeding programs for the Mediterranean Basin. 

S01P12 

Characteristics of ‘Pompia’ a natural citrus hybrid cultivated in Sardinia 

Mignani I. 1 , Mulas M. 2 , Mantegazza R. 1 , Lovigu N. 1 , Spada A. 1 , Nicolosi E. 3 , and Bassi D. 1 

1 University of Milan (DAES), Department of Agricultural and Environmental Science, Italy; 2 University of Sassari (DIPNET), Department 

of the Nature and Land Sciences, Italy; and 3 University of Catania (DAFS), Department of Agricultural and Food Science, Italy. 

mmulas@uniss.it 

The ‘Pompia’ is a probable citrus natural hybrid sporadically growing in the “Baronia” area (East Sardinia, 

Italy). The origin and taxonomic classification of this Citrus taxon is unknown. The fruit shows a yellow-amber 

flavedo at maturity and large size (weight from 200 to 700 g), irregular shape, light-yellow pulp, and low 

juice content. The traditional use as food is limited to the thick albedo after removal of the flavedo tissue 

and of the acid, non-edible pulp, and candying. This research had as its objective a morphological study of 

nine accessions selected from four orchards of ‘Pompia’ in order to sample the observed variability of trees, 

shoots, leaves, and fruits. The results of morphological determinations showed a high similarity of ‘Pompia’ 

samples to lemon and citron species for thorns, fruit size and colour. The presence of small petiole winglets 

was observed only on one accession. AFLP, RAPD, and SCAR analysis allowed the comparison of ‘Pompia’ 

with seven Citrus species: citron, lemon, pummelo, grapefruit, bitter orange, and mandarin. The analysis with 

molecular markers demonstrated a close genetic relationship among ‘Pompia’, lemon, and citron. Moreover, 

the elaboration of the phenotypic and molecular analysis allowed evidencing a high level of similarity of the 

nine ‘Pompia’ accessions. Seven of them probably genetically correspond to the same clone. 


S01

Session 02 

CITRUS GENETICS AND BREEDING 

S02

S02O01 

The triploid mandarin breeding program in Spain 

Navarro L., Aleza P., Cuenca J., Juárez J., Pina J.A., Ortega C., Navarro A., and Ortega V. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain. lnavarro@ivia.es 

Production of seedless citrus fruits is required for the fresh market because consumers do not accept 

seedy fruits. Development of new seedless mandarin cultivars has a high priority for many citrus industries 

worldwide. The recovery of triploid hybrids is the most promising approach to achieve this goal, since triploids 

have a very low pollen and ovule fertility and usually are seedless or produce very low number of seeds, and 

do not induce the formation of seeds in other cultivars by cross pollination. In Spain we are carrying a triploid 

breeding program since 1996 based on 2x X 2x, 2x X 4x and 4x X 2x pollinations followed by embryo rescue 

and flow cytometry, and the use of different approaches to produce new tetraploid parents. The objective 

is to produce new high quality easy peeling and seedless mandarin cultivars. More than thirty spontaneous 

autotetraploid apomictic genotypes to be used as male parents have been selected from seedbeds by flow 

cytometry. Also nine autotetraploid non apomictic genotypes mainly to be used as female parents have been 

obtained by chromosome duplication with treatments of micrografted shoot tips with colchicine. Symmetric 

protoplast fusion is also being used to produce allotetraploid genotypes. So far, we have obtained more 

than 5,500 triploid hybrids from 130 parental combinations by 2x X 2x pollinations, more than 4,300 triploid 

hybrids from 100 parental combinations by 2x X 4x pollinations, and more than 5,600 triploid hybrids from 

103 parental combinations by 4x X 2x pollinations. Recently we have released the first cultivars originated in 

the program, the seedless late maturing mandarins ‘Garbí’ and ‘Safor’, obtained from 2x X 2x crosses. More 

than 400,000 trees of these varieties have been planted by growers during the last three years. 

S02O02 

Triploid seedless mandarin breeding in France 

Froelicher Y., Bouffin J., Dambier D., and Ollitrault P. 

Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), UMR AGAP, France. 

froelicher@cirad.fr 

Small citrus is an increasing component of the world citrus industry. New high quality, parthenocarpic, sterile 

mandarin varieties will play a pivotal role for its sustainable development. To produce seedless varieties, 

the CIRAD breeding program is focused on triploid hybrid selection. The first method to develop triploid 

progenies exploits 2n gametes that are naturally produced by diploid cultivars to obtain triploids in 2x X 

2x crosses. The second method is based on interploid crossings (2x X 4x and 4x X 2x). For the last strategy 

the parental tetraploid gene pool has been diversified by selecting spontaneous tetraploids in apomictic 

cultivars, generating doubled diploids by colchicine treatments and production of allotetraploids by somatic 

hybridization. Several thousand triploid hybrids have been created by CIRAD using these strategies with the 

support of embryo rescue and ploidy evaluation by flow cytometry. This breeding program is supported by 

basic and methodological research performed in collaboration with IVIA (Spain), DAK (Morocco) and INRA 

(France) in the following topics: (1) citrus germplasm management and characterization, (2) studies of 

polyploidization mechanisms, tetraploid meiosis and its implications on the genetic and phenotypic structure 

of triploid progenies, and (3) studies of the implication of polyploidy on genomic and phenotypic expression. 

S02O03 

Mechanism of 2n gametes formation and centromere mapping in citrus 

Aleza P. 1 , Cuenca J. 1 , Juárez J. 1 , Navarro L. 1 , and Ollitrault P. 2 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; and 2 Centre de Coopération 

Internationale en Recherche Agronomique pour le Développement (CIRAD), BIOS, France. aleza@ivia.es 

Citrus triploid hybrids can be recovered by 2x X 2x hybridisations as a consequence of 2n gamete formation. 

Two main meiotic processes are at the origin of such gametes, the first division restitution (FDR) and the 

second division restitution (SDR). These two mechanisms lead to very different gamete genetic structures. 


S02

S02 

Particularly, the opposite feature of parental heterozygosity restitution (PHR) is observed in relation with the 

distance to the centromere. Without previous knowledge on centromere location, the determination of the 

restitution mechanism requires an analysis of the frequency of PHR within a large population with numerous 

codominant markers. With this method we determined that SDR is the mechanism involved in clementines 

and ‘Fortune’ mandarin. With SDR, PHR is a direct function of the distance of the considered locus to the 

centromere. Therefore the analysis of the evolution of PHR, within a linkage group (LG) allows mapping of the 

centromere position. Centromere has been located in the 9 LGs of the clementine genetic map by genotyping 

triploid hybrids with SSR and SNP markers. Analysis of the 2n gamete allelic configuration with loci close to 

the centromere can shed light on the restitution mechanism at the individual level and open the way for 

simplified study of this mechanism in a large range of genotypes. We are applying this approach to analyse 

the 2n gamete origin in several genotypes of mandarin and one genotype of sweet orange. 

S02O04 

Experiences in the development, release and commercialization of new irradiated citrus varieties 

from the citrus breeding program at the University of California Riverside 

Williams T.E. 

University of California Riverside (UCR), Botany and Plant Sciences, United States. timwill@ucr.edu 

The use of irradiation in the mutation breeding scheme of citrus breeding programs is now quite widespread 

with most programs in the major citrus producing countries actively pursuing new selections. Irradiation, used 

principally to reduce the seed content of normally seedy varieties, represents a more rapid method of achieving 

these goals than does hybridization. Some programs, notably in Israel and California, have a longer history 

with these techniques, not only in the development of new varieties but especially as relates to the release 

and commercialization of the newly developed selections. The experiences in the Citrus Breeding Program 

at the University of California Riverside have included the development, release and commercialization of 

several mandarin selections including ‘Tango’, ‘DaisySL’, ‘KinnowLS’, and ‘FairchildLS’ along with others in the 

‘pipeline’. The presentation will discuss the specific approaches used by the UCR Citrus Breeding Program 

during the irradiation process, the criteria and standards used in the selection of promising new candidates 

and the general experiences and problems encountered during the release and commercialization phases. 

S02O05 

Citrus breeding program in Chile 

Martiz J., and Montañola M.J. 

Pontificia Universidad Católica de Chile (PUC), Facultad de Agronomía e ingeniería forestal, departamento de Fruticultura, Chile. 

mmontano@uc.cl 

Mandarin production and exports from Chile have shown a huge growth in the last ten years. During the 90’s 

the most important cultivar was ‘Clemenules’ and since 2005 mandarin hybrids are being planted to supply 

late season markets. This has resulted in the production of fruit with seeds due to cross pollination causing 

big losses to Chilean producers. In 2007 citrus breeding program was initiated in the Pontificia Universidad 

Católica de Chile with the support of CIRAD (France) and University of California Riverside. The aim of this 

program was to obtain seedless mandarin and lemon cultivars. Strategies used are induced mutation by gamma 

irradiation, in vitro triploid rescue obtained from diploid crosses, production of auto-tetraploid plants and 

the establishment of a protoplast fusion protocol. Irradiation technique has resulted in the establishment of 

5700 mandarins and 2500 lemons in a field trial located in Pomaire, Chile (33°39’S, 71°10’W). Field evaluation 

resulted in the selection of 164 lemon and 14 mandarin seedless selections, 4 lemon thornless selection, and 

2 ornamental types. Our methodology allowed an early selection of seedless genotypes and quickly reduced 

the number of plants under evaluation. 118 triploids were obtained through in vitro rescue from diploid 

mandarins cross pollinations. These genotypes are currently under agricultural practices to induce flowering 

and are prone to be planted in commercial trials. 9 tetraploid of reduced juvenility were obtained with the 

use of colchicine in axillary buds. They will be used in cross pollinations in 2012 spring. Finally a protoplast 

fusion protocol has been developed under our conditions. The results of this program have a high impact 

for the Chilean citrus industry and the academy, since they have allowed creating varieties adapted to local 

conditions, a new line of research and training for new professionals. 


S02O06 

Citrus breeding in South Africa: the latest developments in the programme run by the ARC- 

Institute for tropical and subtropical crops. 

Sippel A.D., Bijzet Z., Froneman I.J., Combrink N.K., Maritz J.G.J., Hannweg K.F., Severn-Ellis A.A., and Manicom B.Q. 

Agricultural Research Council - Institute for Tropical and Subtropical Crops (ARC - ITSC), Plant Improvement, South Africa. 

arthur@arc.agric.za 

The South African Agricultural Research Council’s Citrus Plant Improvement Programme run by the Institute 

for Tropical and Subtropical Crops consists of a number of separate projects. These involve conventional scion 

breeding to improve productivity and quality, rootstock breeding for soil adaption, disease resistance and 

improved yields, mutation breeding, and evaluation of both scions and rootstocks in different climatic zones. 

These projects are also supported through the Citrus Improvement Programme, a vast germplasm collection, 

various biotechnology techniques such as embryo rescue and ploidy manipulation, and the use of molecular 

markers to distinguish between, at this stage citrus mandarin selections. This paper will give a short overview 

of the research activities within each of the projects, as well as the most important results achieved by each. 

S02O07 

Highlights of the University of Florida, Citrus Research and Education Center’s comprehensive 

citrus breeding and genetics program 

Grosser J.W., Gmitter Jr. F.G., Ling P., and Castle W.S. 

University of Florida, Institute of Food and Agricultural Sciences (IFAS), Citrus Research and Education Center (CREC), USA. 

jgrosser@ufl.edu 

A comprehensive citrus breeding and genetics program was established at the UF/CREC during the mid-1980’s 

combining conventional breeding with tools provided by tissue culture, emerging biotechnologies, molecular 

genetics and genomics. Scion Improvement: The Florida citrus industry is 90% processing sweet oranges. A 

major goal has been to develop new cultivars for Not From Concentrate juice production with emphasis on 

increasing juice quality and expanding seasonal availability. Improved clones from seedling introductions, 

budwood irradiation and somaclonal variation will be discussed. The fresh fruit industry in Florida is dominated 

by grapefruit and seedy mandarins. Primary objectives for fresh fruit improvement include expanding 

seasonal availability, development of Canker tolerant and low furanocoumarin grapefruit, and development 

of seedless, easy-peeling mandarins. The focus of our program has been on parent development, and 

seedless triploid production via interploid crosses; strategies and successes will be discussed. Rootstock 

Improvement: Initial focus was on improving soil adaptation, tree-size control to facilitate harvesting and 

cold-protection, and disease resistance, especially to blight, CTV induced quick decline and Phytophthora. 

Breeding objectives have since been expanded to include tolerance of the Diaprepes/Phytophthora complex 

and HLB, and development of rootstocks that facilitate advanced citrus production systems (ACPS). Progress 

from conventional breeding (both 2x and 4x) and somatic hybridization will be discussed. Genetic Engineering 

and Genomics: Due to the HLB and Canker epidemics, focus has been on disease resistance gene discovery, 

transformation, and evaluation of transgenic plants; progress will be discussed. 

S02O08 

Advance in S allele determination, S allele frequencies and S-genotyping in citrus 

Wakana A., Handayani E., Kim J.H., Miyazaki R., Mori T., Sato M., and Sakai K. 

Kyushu Univesity, Horticultural Science, Japan. wakana@agr.kyushu-u.ac.jp 

Gametophytic self-incompatibility (SI) is known in pummelo, mandarin and cultivars with pummelo in their 

pedigrees. Despite the importance of SI for citrus cultivation and breeding, little is known about the SI 

genotypes of citrus cultivars. In this study, homozygous S 1 seedlings for the S gene were produced through 

bud self-pollination of five monoembryonic SI cultivars, i.e., ‘Banpeiyu’ and ‘Hirado Buntan’ pummelos 

(Citrus grandis), clementine (Citrus clementina) and ‘Ellendale’ mandarins and ‘Hassaku’ (Citrus hassaku). 

The homozygosity of S 1 seedlings for S gene was determined by pollen tube penetration in the stylar base 8 


S02

S02 

days after pollination with the parent, and homozygous genotypes were determined similarly by pollinations 

between the homozygous S 1 seedlings. The determined homozygous S 1 seedlings, whose S genotypes were 

S 1 S 1 , S 2 S 2 , S 3 S 3 and so on, were pollinated to about 100 SI (S n S n’ ) or SC (S f S f or S f S n ) cultivars and accessions. 

The cultivars or accessions arresting pollen tubes in their stylar base were determined to have the same 

allele as that of the pollinated homozygous seedling. Cultivars whose S genotypes were determined were 

‘Banpeiyu’ (S 1 S 2 ), ‘Natsudaidai’ (S f S 2 ), ‘Tosa Buntan’ (S 1 S 3 ), clementine (S 3 S 11 ), ‘Hirado Buntan’ (S 9 S 10 ), and 

so on. Frequency of S n alleles, except for S f allele, was 16.4% for S 1 , 11.6% for S 2 , 11.8% for S 3 , 10.6% for 

S 4 , 5.1% for S 5 , 5.7% for S 9 , 2.9% for S 10 and 13.7% for S 11 . Among Japanese cultivars and accessions with 

the determined S alleles, those with S 4 allele were considered to originate from ‘Kunenbo’ tangor (Citrus 

nobilis) or hybrids with ‘Kunenbo’ in their pedigrees. The Japanese cultivars or accessions with the S 4 allele 

were satsuma mandarin (Citrus unshiu), ‘Hassaku’ (S 4 S 5 ), ‘Ogonkan’ (Citrus flaviculpus), ‘Keraji’ (Citrus keraji), 

‘Kabuchi’ (C. keraji) and so on. Introgression of the S 4 allele into citrus cultivars is discussed. 

S02O09 

Integrated profiling of furanocoumarins (FCs) in grapefruit and derived hybrids toward selection 

of low FCs varieties 

Chen C. 1 , Gmitter Jr. F.G. 1 , Cancalon P. 2 , and Greenblatt D.J. 3 

1 University of Florida, Citrus Research and Education Center (UF-CREC), Department of Horticultural Sciences, USA; 2 Florida Department 

of Citrus, Scientific Division (FDOC), USA; and 3 Tufts University, School of Medicine (TUSM), Department of Molecular Physiology and 

Pharmacology, USA. cxchen@ufl.edu 

Furanocoumarins (FCs) are a class of organic chemical components in grapefruits and other food plants. 

Consumption of grapefruit juice can potentially increase the bioavailability of a number of clinically prescribed 

drugs, induce grapefruit-drug interactions, and therefore, some physicians recommend that grapefruit juice 

should be avoided by patients taking these drugs. To develop low FC grapefruit cultivars, integrated approaches 

to profile FCs were used to facilitate achieving the goal, including quantifying different FCs in grapefruit and 

pummelo, characterizing the inheritance using hybrid populations, identifying some key controlling genes in 

the furanocoumarin biosynthesis pathway, and determining the inhibitory potency of different hybrids and 

FCs. We monitored seven FCs, 6’,7’-dihydroxybergamottin (6,7-DHB), bergamottin, bergaptol, isoimperatorin, 

epoxybergamottin (EBM), 5’,8’-dimethylallyloxypsoralen (5,8-DMP), and Paradisin C, in randomly selected 

hybrids, and found 6,7-DHB, bergamottin, paradisin C, and bergaptol inherited in a 1:1 co-segregating manner, 

with strong correlations (R 2 up to 0.909) among them, as well as with in vitro inhibitory potency versus human 

cytochrome P450-3A activity (R 2 =0.96). At least one gene in the pathway was identified to show differential 

expression between high and low FC varieties. The phytochemical, genetic, genomic, and pharmaceutical 

profiles of the FCs are leading to a genomic and breeding solution to the grapefruit FC-drug interaction issue. 

S02O10 

Breeding new grapefruit-like varieties with low furanocoumarin contents 

Weissberg M., Yaniv Y., Sobolev I., Fidle L., and Carmi N. 

The Volcani Center (ARO), Fruit Tree Sciences, Israel. nircarmi@agri.gov.il 

Furanocoumarins are compounds present in pummelo and grapefruit (grapefruit is a probable hybrid of 

pummelo and sweet-orange) and absent in mandarin and orange fruit. People that consume different types 

of drugs, such as statins, antihistamines, and certain antibiotics, are forbidden to consume grapefruits and 

pummelo because of the inhibitory affect of furanocoumarins on cytochrome P450 3A4 activity, a key enzyme 

involved in drug metabolism, and its inhibition may lead to severe health risks. Since it is anticipated that 50% 

of the population above the age of 40 will need to take statins, we predict a drastic drop in grapefruit juice 

consumption in the near future. Therefore, to address this problem, we aimed to develop a new grapefruitlike 

variety without furanocoumarins. For that purpose, we screened using LC-MS various grapefruit-like 

hybrids for presence of furanocoumarins, and found that most of the genotypes tested, such as ‘Marsh’ 

grapefruit, ‘Chandler’ and ‘Flamingo’ pummelos, and various grapefruit-like hybrids, such as ‘Einat’ (‘Hudson’ 

grapefruit X ‘acidless pummelo’) and ‘Michal’ mandarin X ‘Duncan’ grapefruit, contained high amounts of 


furanocoumarins. However, a particular hybrid between ‘Chandler’ pummelo X ‘Orah’ mandarin, named 

‘Aliza’, had low furanocoumarin content. At the same time, the observed level of naringin, which provides 

typical grapefruit bitter flavor, in ‘Aliza’ fruit was the same as that detected in ‘Marsh’ grapefruit. 

S02O11 

Genotypic variation of rind colour in citrus tangor ‘Kiyomi’ progenies 

Combrink N.K. 1 , Bijzet Z. 1 , Sippel A.D. 1 , Booyse M. 2 , and Labuschagne M.T. 3 

1 Agricultural Research Council - Insitute for tropical and Subtripical Crops (ARC-ITSC), Plant Improvement, South Africa; 2 Agricultural 

Research Council - Biometry (ARC-Biometry), Biometry, South Africa; and 3 University of the Free State (UFS), Plant Breeding, South 

Africa. combrinkn@arc.agric.za 

Rind colour is the most important characteristic contributing to a fruit’s appearance and therefore the 

improvement of rind colour has been a longstanding aim of citrus breeding programmes. However, due to the 

lack of information on the inheritance of rind colour in citrus, the breeder faces a difficult task when planning 

crosses for breeding new cultivars. By quantifying the variation in a population the breeder can study the 

relationships between the hybrids and parents and gain an understanding of how certain characteristics are 

inherited. Therefore a study was undertaken to investigate the variation in rind colour, as chroma coordinates 

L*, a* and b*, in six mandarin families, where female parent ‘Kiyomi’ tangor (Citrus unshiu x Citrus sinensis) 

was crossed with male parents ‘Dancy’, ‘Hansen’, ‘Rishon’, ‘Roma’, ‘Shani’ and ‘Sunburst’ mandarins (Citrus 

reticulata). A significant level of variation was found between both the parents and the families for all the 

colour coordinates. A greater variation was found within the families than between the families, indicating a 

high level of genetic variation within the families, while the within tree variation was lower than the within 

family variation. All the families showed an improvement in the population for rind colour over the female 

parent ‘Kiyomi’ for L* and b*, while all the families except for the ‘Kiyomi’ x ‘Dancy’ family showed an 

improvement for a*. The ‘Kiyomi’ x ‘Dancy’ and ‘Kiyomi’ x ‘Roma’ families were found to have a population 

with a lighter, more yellow-orange rind colour, while the ‘Kiyomi’ x ‘Hansen’, ‘Kiyomi’ x ‘Rishon’, ‘Kiyomi’ 

x ‘Shani’ and ‘Kiyomi’ x ‘Sunburst’ families had a population with a deeper, more orange-red rind colour. 

The intraclass correlation coefficient relevant to selection within the families was fairly low, indicating the 

variation was only partly genetic and the environment contributed to the phenotypic variation. Therefore a 

mean performance of multiple year’s data should be used for effective selection. 

S02O12 

Rootstock effects on mandarin fruit traits under control and salinity conditions 

Raga V. 1 , Bernet G.P. 1 , Carbonell E.A. 2 , and Asíns M.J. 1 

1 Instituto Valenciano de Investigaciones Agrarias (I.V.I.A.), Centro de Protección Vegetal y Biotecnología, Spain; and 2 Instituto 

Valenciano de Investigaciones Agrarias (I.V.I.A.), Biometría, Spain. raga_ver@gva.es 

The objective of this study is to explore rootstock genetic effects on salt tolerance in terms of fruit yield. 

A seedling population from hybrids between Citrus volkameriana (V) and Poncirus trifoliata (P), and its 

grandparents (V and P) were grafted with ‘Hashimoto’ mandarin. Trees were maintained in a screenhouse and 

salt treatment (25 mM NaCl) was applied from June to September for 5 years (2004-2008) to 32 genotypes 

and 18 controls. Rootstocks were genotyped for 5 salt tolerance candidate genes. Alleles of 96 and 73 markers 

segregating at the V and P genomes, respectively, in the VxP nucellar seedlings were studied for marker-trait 

associations. Significant effects for rootstock genotype (G) and treatment (E) were found for most traits. 

Salinity decreased yield and juice volume, but improved total soluble solids and rind thickness. Year effects 

were highly significant in most cases. GxE interaction was found for fruit weight, total fruit weight, leaf water 

content and leaf [Na]. Trait heritabilities of rootstock effects ranged from low to very low and no fruit yield 

trait had consistent, significant correlations through years with any non-fruit trait. Two salt tolerant candidates 

were associated with fruit yield traits, but only under control conditions. Segregations at 8 and 9 loci on the V 

and P genomes, respectively, were highly associated with fruit yield under the salinity treatment. Therefore, 

phenotypic selection assisted by markers linked to these QTL is more efficient than just phenotypic selection 

to obtain rootstocks that confer salt tolerance to the grafted mandarin. 


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S02O13 

Extension of a citrus genetic linkage map for QTL mapping of freeze tolerance 

Hong Q.-B., Ma X.J., Gong G.-Z., and Peng Z.C. 

Citrus Research Institute, Chinese Academy of Agricultural Sciences and Southwest University, National Citrus Engineering Research 

Center, Chongqing, China. hongqb@sina.com 

Freeze limits the cultivated area of citrus. Periodically freeze events in some producing areas caused severe 

damages to citrus harvest and low temperature during extreme climate change often affected the citrus 

global production in recent years. To develop and cultivate freeze tolerant cultivars is the most effective way 

to avoid damages caused by freeze. Cold tolerance is considered a quantitative trait in plant. In this research, 

QTL mapping was used to find loci and molecular markers putatively related with freeze tolerance in citrus. A 

new linkage map was established by combining the segregating data of markers in a published map and SSR 

markers newly developed from citrus EST and clementine BAC-end sequences. New map integrated 452 SSR 

markers with 9 linkage groups and covered 923.3 cM of citrus genome with an average genetic distance at 

2.04 cM between adjacent markers. Freeze tolerance of the mapping population of parents and 68 progenies 

was tested by the method of electrolyte leakage in the end of December after more than one month low 

temperature hardening and semi-lethal low temperature (LT50) was estimated with logistic equation. The 

distribution of LT50 in the mapping population was not deviated from a normal distribution. QTL analysis was 

carried out with Map QTL5.0 software. Four QTLs were indentified at LOD≥3.0 using Multiple QTL Mapping 

(MQM) procedure, which could explain 29.3%, 23.1%, 44.7% and 21.0% of the phenotypic variation. These 

QTLs were mapped on the linkage group 2, 4, 3 and 1 respectively. The identified QTL areas and nearby 

markers should be useful for citrus freeze tolerance research and breeding in the future. 

S02O14 

Location of a chromosome region linked to Alternaria Brown Spot resistance from the evaluation 

of triploid mandarin populations 

Cuenca J. 1 , Aleza P. 1 , Iborra E. 1 , Vicent A. 1 , Ollitrault P. 2 , and Navarro L. 1 


Internationale en Recherche Agronomique pour le Développement (CIRAD), BIOS, France. jcuenca@ivia.es 

Alternaria Brown Spot resistance in citrus has been described in diploid progenies as controlled by a single 

recessive allele (r). The objectives of this study were (1) to map chromosome regions that could be associated 

to Alternaria alternata resistance and (2) to analyse the inheritance of the resistance in triploid families 

resulting from 2n gametes and interploid crosses. Bulk segregant analysis coupled with genome scan (650 

Single Nucleotide Polymorphism –SNP– markers genotyped with GoldenGate array) was used to identify 

genomic regions linked to the A. alternata resistance gene using a triploid progeny from a SrXrr cross. The 

results confirmed the monolocus inheritance of A. alternata resistance and revealed 44 SNPs differentiating the 

resistant and susceptible bulks within a 17 cM region near the centromere on chromosome III. De novo mapping 

from individual genotyping with 9 markers revealed that the A. alternata resistance gene could be located at 

9.7 cM from the centromere. Two flanking markers were selected to perform marker assisted selection. Three 

populations from 2xX2x crosses sharing the female genitor (SrXrr, SrXSr and SrXSS) and one population from a 

2xX4x cross (rrXSSrr) were evaluated for A. alternata resistance. Segregations indicate that 2xX2x crosses are 

better to obtain more resistant genotypes for a centromeric gene controlled by a recessive allele than 2xX4x 

crosses, since less heterozygosity is transmitted by 2n gametes than by gametes of doubled-diploids. 

S02P01 

Investigating the parentage of ‘Orri’ and ‘Fortune’ mandarin hybrids 

Barry G.H. 1 , Gmitter F.G. 2 , Chunxian C. 2 , Roose M.L. 3 , and McCollum G. 4 

1 XLnT Citrus company (XLnT Citrus), South Africa; 2 University of Florida-Institute of Food and Agricultural Science, Citrus Research and 

Education Center (UF-IFAS, CREC), USA; 3 University of California (UCR), Department of Botany and Plant Sciences, USA; and 4 United 

States Horticultural Research Laboratory, Agricultural Research Service, United States Department of Agriculture (USHRL-ARS, USDA), 

USA. ghbarry@gmail.com 

Germplasm characterization is now possible with improved molecular analysis tools with a greater ability to 

detect polymorphisms. Previously citrus cultivars were primarily described according to their morphological 


or horticultural traits, but trueness-to-type can now be confirmed using molecular markers, thereby limiting 

inadvertent cultivar misidentification. However, following routine testing the reported parentage of two 

mandarin hybrids is now questioned. ‘Orri’ mandarin is derived from ‘Orah’ mandarin hybrid by induced 

mutation, and was bred by Spiegel-Roy and Vardi (The Volcani Center, Israel) with ‘Temple’ tangor and ‘Dancy’ 

mandarin reported as the parents. ‘Orri’ is prized in many markets for its excellent organoleptic qualities, and 

other favorable traits. With ‘Dancy’ as the pollen parent, at least some degree of susceptibility of ‘Orri’ to 

Alternaria Brown Spot (ABS) might be expected, but more likely to have inherited a high degree of susceptibility; 

yet it appears to be immune to ABS. SSR analysis provided evidence that excludes ‘Dancy’ as the pollen parent 

of ‘Orah’. Further testing has revealed the likely candidate as the pollen parent. ‘Fortune’ mandarin was a 

popular late-maturing mandarin cultivar until the high incidence of ABS rendered the cultivar uneconomical 

to produce. This exceptionally late, high quality, attractive cultivar is reported to have originated from a 

clementine mandarin x ‘Dancy’ cross made by Furr (USDA, Indio, California). ‘Fortune’ is used as a female 

parent in breeding programs. However, two independent molecular marker studies revealed that the pollen 

parent of ‘Fortune’ is actually ‘Orlando’ tangelo and not ‘Dancy’. In both cases, the pollen parent of ‘Orri’ and 

‘Fortune’ mandarin hybrids appears to not be ‘Dancy’ as published. This information will assist geneticists and 

breeders to re-interpret heritability studies on ABS susceptibility of mandarins and their hybrids. 

S02P02 

Simple PCR-based tolls provide molecular identification of the main rootstock used in Sao Paulo 

State, Brazil. 

Coletta-Filho H.D., Pompeu-Jr. J., Francisco C.S., and Machado M.A. 

Centro APTA Citros Sylvio Moreira (IAC), Laboratório Biotecnologia, Brazil. carolinaf@centrodecitricultura.br 

Distinguishing between ‘Sunki’ and ‘Cleopatra’ mandarins as well as between ‘Carrizo’ or ‘Troyer’ citranges 

and ‘Swingle’ citrumelo very early in the nursery based only based on their respective leaf morphology 

could result in erroneous interpretation. Horticultural advantages of ‘Swingle’ rootstock are incomparable 

to ‘Carrizo’ under our conditions (Sao Paulo State, Brazil). The crescent diversification of citrus rootstock 

varieties in SP state has demanded, in particular situations, for identification of rootstock varieties very early 

in the nursery, sometimes as a consequence of accidental mixture of seeds. To help growers and nurseryman 

accurately identify rootstock varieties, we developed PCR-based tools that identify most of rootstocks used in 

SP state. Information from three-selected RAPD 10mer primers (M04-ggcggttgtc, M15-ctggcgtgtc, and AB18gacctaccac) 

can be successfully used to identify and genetically separate citrange, citrumelo, and Poncirus 

trifoliata. Another 10mer primer (R04-cccgtagcac) identifies ‘Rangpur’ lime (Citrus limonia) and separates 

it from ‘Volkameriano’, and ‘Siciliano’ lemons. From the fingerprints generated by those 10-mer primers, 

repeatable and consistently well-amplified DNA fragments are used as variety-specific markers. Also, ‘Sunki’ 

and ‘Cleopatra’ mandarins are identified by the microsatellites CCSM-6R (cctctattaatgtgcctg) and CCSM-6F 

(atctgtgtgaggactgaa) primers. These simple PCR based protocols have been used to avoid significant economic 

losses by the early and correct identification of rootstocks in SP state nurseries. 

Support: INCT Citros (CNPQ and FAPESP) 

S02P03 

Assignment of SNP allelic configuration in polyploids using Competitive Allele-Specific PCR: 

application to triploid citrus progenies 

Cuenca J. 1 , Aleza P. 1 , Navarro L. 1 , and Ollitrault P. 2 


Internationale en Recherche Agronomique pour le Développement (CIRAD), BIOS, France. jcuenca@ivia.es 

Estimation of DNA allele doses in polyploid genotypes is essential to assign the allelic configuration for the 

different types of heterozygosity for parents and segregating progenies. It is of special interest in citrus with the 

implementation of extensive triploid breeding programs to develop new seedless varieties. Single nucleotide 

polymorphisms (SNPs) are becoming the most important class of molecular markers and we have tested the 

potential of KASPar technology (based on competitive allele-specific PCR) to infer allele doses of SNP markers in 


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polyploid citrus. DNAs from haploids Citrus clementina and Citrus maxima were mixed at different proportions 

to test the accuracy of the technique for quantitative analysis. All analyzed 7 SNPs provided clear clustering 

related with allele doses. DNA mixes at intermediary proportions revealed high correlation coefficients between 

observed and expected data (mean = 0.9796; sd = 0.0094). For all SNPs, separated cluster analyses and ANOVA 

from mixed DNA data formed all expected homogeneous groups, with correct assignation for practically 

all samples. Moreover, two triploid populations were easily genotyped and results were in agreement with 

expected segregations. KASPar technology is a routine and a cost-effective technique to assess the allele doses 

at the DNA level, which is especially interesting in citrus triploid breeding programs. Moreover, it could be also 

used to correlate genomic and transcriptomic doses in allele specific expression analyses. 

S02P04 

The parentage analysis contributes to the validation of high throughput SNP genotype calls of citrus 

Fujii H. 1 , Nonaka K. 1 , Kita M. 1 , Shimada T. 1 , Endo T. 1 , Kuniga T. 2 , Ikoma Y. 1 , and Omura M. 3 

1 NARO Institute of Fruit Tree Science (NIFTS), Japan; 2 NARO Western Region Agricultural Research Center (NARO/WARC), Japan; and 

3 Shizuoka University, Faculty of Agriculture, Japan. hfujii@affrc.go.jp 

High-throughput genotyping is an important breeding tool to provide genome wide genotyping of germplasm for 

breeding and the selection of markers through linkage mapping. However, the validation system for genotyping 

calls from the automatic analysis has not been adequately developed to apply the high-throughput genotyping 

system in a practical fashion, because the marker data sets derived from DNA markers often contain missing or 

questionable genotype calls. Therefore, the objective of this study was to develop validation procedures using 

SNP data sets from a previously developed 384 multiplexed SNP array, named CitSGA-1, for the genotyping 

of Citrus cultivars. For this purpose, we initially used the manufacture’s criterion that included: (1) the call 

frequency scores (over 0.9) for SNPs and (2) the GC10 and GC50 scores of samples. Thereafter, the following 

validation procedures were investigated: (3) removal of monomorphic SNPs genotype calls, (4) removal of 

No Call SNPs, and (5) removal of SNPs with discrepancies in the parentage analysis. In these procedures, the 

parentage analysis could detect the genetic discrepancy between parents and progeny in the reliable criteria. 

The obtained reliable SNP types were also tested for the reproducibility of calls by the replicated genotyping of 

accessions on the same SNPs. The results confirm these the validation procedures, which include the design of 

samples for parentage assays and the replicates necessary to obtain the reliability of large genotype calls. 

S02P05 

Comparative values of SSRs, SNPs and InDels for citrus genetic diversity analysis 

Ollitrault P. 1 , Garcia-Lor A. 2 , Terol J. 3 , Curk F. 4 , Ollitrault F. 2 , Talon M. 3 , and Navarro L. 2 

1 Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), BIOS, France; 2 Instituto Valenciano 

de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; 3 Instituto Valenciano de Investigaciones 

Agrarias (IVIA), Centro de Genómica, Spain; and 4 Institut National de la Recherche Agronomique (INRA), GAP, France. 

patrick.ollitrault @cirad.fr 

SSRs have long been considered as almost ideal markers for genetic diversity analysis. With the increasing 

availability of sequencing data, SNPs and InDels become major classes of codominant markers with genome 

wide coverage. We have analyzed the respective values of SSRs, InDels, and SNPs for intra and interspecific 

Citrus genetic diversity analysis. Moreover, we have compared the diversity structure revealed by markers 

mined in a single heterozygous genotype (the clementine) and markers mined in a large interspecific survey. 

A random set of 25 markers was selected for each marker class to genotype 48 citrus accessions. SSRs were 

the most polymorphic markers at the intraspecific level allowing complete varietal differentiation within basic 

taxa (Citrus reticulata, Citrus maxima, Citrus medica). However, SSRs gave the lowest values for interspecific 

differentiation, followed by SNPs and InDels, that displayed low intraspecific variability but high interspecific 

differentiation. A clear effect of the discovery panel was observed for SNPs and InDels. The ascertainment 

biases associated with the clementine heterozygosity mining resulted mainly in an over estimation of within 

C. reticulata diversity and an underestimation of the interspecific differentiation. Therefore SSRs are very 

useful for intraspecific structure analysis while SNPs and InDels mined in large discovery panel will be more 

powerful to decipher the interspecific mosaic structure of secondary cultivated species. 


S02P06 

Preliminary research on genes and proteins related to a spontaneous mutant of Citrus reticulata 

Zeng J.W. 1 , Yi G.J. 2 , Jiang B. 1 , Zhong Y. 1 , and Zhong G.Y. 1 

1 Institute of Fruit Tree Research, Guangdong Academy of Agricultural Science, China; and 2 Guangdong Academy of Agricultural 

Science, China. zhongyun99cn@163.com 

Bud mutations of citrus happen frequently and are the main natural resource for new cultivars. ‘Mingliutianju’ 

(Citrus reticulata ‘Mingliutianju’, MP) is a novel late ripening, very productive mandarin cultivar selected from 

‘Chuntianju’ (C. reticulata ‘Chuntianju’, CP) through spontaneous bud mutation. In addition, the cultivar is 

morphologically contrast to the smooth fruit of its parent ‘Chuntianju’ by having prominent vertical narrow 

strips on its fruit surface. Large-scale analysis of gene expression differences between peels of MP and CP was 

performed at the 12th week and the 23rd week post flowering using Affymetrix GeneChip® citrus genome array. 

Altogether, 395 differentially expressed genes, including 132 up-regulated and 263 down-regulated genes, were 

identified in the mutant. Singular Enrichment Analysis (SEA) and Parametric Analysis of Gene Set Enrichment 

(PAGE) were performed and 7 statistically significantly differential-expressed genes were selected for further 

studies. Results from semiquantitative RT-PCR performed on these 7 genes were generally correlated with those 

observed with the microarray. These seven genes include three UDP-glucosyltransferase genes, two disease 

resistance-responsive protein-related genes, one chitinase gene and one protein kinase gene. Thirty three 

differentially expressed proteins were identified by two-dimensional gel electrophoresis using the same material. 

The differential proteins included 17 up-regulated and 16 down-regulated in the mutant. Pathway identification 

was conducted on these 33 differential expressed proteins through the web-based platform KOBAS. When these 

KEGG pathways were arranged according to their P values, flavonol biosynthetic process pathway ranked first. 

S02P07 

Allelic diversity of Ferritin III and PMT IV genes related to iron chlorosis in some citrus rootstocks 

Aka Kacar Y. 1 , Simsek O. 1 , Donmez D. 1 , Boncuk M. 1 , Yesiloglu T. 1 , and Ollitrault P. 2 

1 Cukurova University (Cu), Horticulture Department, Turkey; and 2 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de 

Protección Vegetal y Biotecnología, Spain. ykacar@cu.edu.tr 

Iron (Fe) is one of the most important elements in plant mineral nutrition. Fe deficiency is critical abiotic 

stress factor for Mediterranean citriculture and the development of marker assisted selection (MAS) for this 

trait would be a great aid for rootstock breeding. In this study DNA sequencing and SSCP (Single Stranded 

Conformation Polymorphism) analysis were performed to discover allelic diversity of genes related to iron 

chlorosis tolerance in citrus. Two iron chlorosis tolerance candidate genes were selected from existing Citrus 

ESTs databases and Arabidopsis thaliana genome databases. Ferritin-3 chloroplast precursor and putative 

membrane transporter candidate gene sequences were used to define primers in conserved regions. Six 

citrus genotypes from the basic taxon of Citrus where used to identify polymorphic areas in the genes. Direct 

sequencing of amplified DNA fragments of candidate genes was performed and SNPs (single-nucleotide 

polymorphisms) and InDels (Insertions/Deletions) where searched after sequence alignment. A total of 6840 

bp DNA fragments were sequenced and 263 SNPs and 15 InDels were determined. New primers were defined, 

in conserved areas flanking polymorphic ones, for Single Strand Conformation Polymorphism (SSCP) analysis. 

SSCP-PCR analysis was performed with twenty-five Citrus genotypes. The neighbor joining method was used 

for cluster analysis. Phylogenetic origin of the alleles and genetic relationships of genotypes were discussed. 

S02P08 

Genetic mapping of QTLs associated with drought tolerance in citrus 

Dutra-Souza J. 1 , Cristofani-Yaly M. 2 , Machado M.A. 2 , and Oliveira A.C. 1 

1 Universidade Estadual do Sudoeste da Bahia (UESB), Brazil; and 2 Centro de Citricultura Sylvio Moreira, Instituto Agronômico (IAC), 

Laboratório de Biotecnologia, Brazil. mariangela@centrodecitricultura.br 

A population of 73 hybrids of ‘Rangpur’ lime (Citrus limonia) and ‘Swingle’ citrumelo (Citrus paradisi x Poncirus 

trifoliata), kept in plastic bags of 3.8 liters in a greenhouse, had water removed for 15 days. The gradient 


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of drought stress symptoms, after irrigation suspension, was measured by scores on a scale [absence of 

symptoms (0), wilting of leaves (1), leaf rolling (2), complete drying of the leaf, characterized by the change 

from green to brown (3) and drop of leaves (4)]. The symptoms were evaluated in four periods, the scores were 

pooled and the ‘Index of Intensity of Symptoms of Drought’ (IISD, from 0 to 100) was created, adapted from 

Czemainski (1999). Results of IISD were subsequently used to find QTLs to drought tolerance in an integrated 

genetic map of ‘Rangpur’ lime and ‘Swingle’ citrumelo, previously constructed, allowing the identification of 

seven QTLs in two linkage groups (LG) of the map. 

Financial Support: CAPES and INCT-Citrus 

S02P09 

Evaluation of resistance of ‘Pera’ (Citrus sinensis) genotypes to Citrus Canker in field and greenhouse 

conditions 

Goncalves-Zuliani A. 1 , Nunes W.M.C. 1 , Zanutto C. 1 , Croce Filho J. 2 , and Nocchi P.T.M. 1 

1Universidade Estadual de Maringa (UEM), Nucleo de Pesquisa em Biotecnologia Aplicada-NBA, Brazil; and 2Secretaria de Estado da 

Agricultura e Abastecimento (SEAB), Departamento de Fiscalizacao - DEFIS, Brazil. william.nunes@pq.cnpq.br 

The use of resistant genotypes is an important alternative in the control of Citrus Canker caused to Xanthomonas 

citri. The objective of this study was to evaluate genotypes of the ‘Pera’ sweet orange for resistance to 

Citrus Canker in the field and under greenhouse conditions. A total of 25 genotypes of ‘Pera’ sweet orange 

were evaluated in orchards and in a greenhouse in the state of Parana, Brazil. To determine the incidence 

and severity of disease in the field 10 plants were evaluated per genotype, with samples consisting of four 

branches per plant. Data collected included counts of the total number of leaves, the number of diseased 

leaves, number of lesions and an inferred average of severity using a diagrammatic scale. In greenhouse 

treatment, leaves were inoculated by piercing with a needle (0.55 x 0.20 mm), containing X. citri inoculum 

adjusted to 10 8 CFU / ml at 600 nm and evaluated with the aid of a micrometer. The results were submitted 

to ANOVA and means were compared by Scott Knott test at 5% probability. In field conditions ‘Pera EEL’, ‘Pera 

Coroada’ and ‘Pera Ovale Siracusa’ genotypes showed no symptoms of disease in the three regions evaluated. 

In the greenhouse test, ‘Pera EEL’ (1.74 mm) and ‘IAC 2000/1’ (1.73 mm) genotypes showed smaller diameters 

lesions. An increase in diameter of the lesions was observed over time, requiring 61 days after inoculation 

(DAI) for the lesion size to be stabilized. 

S02P10 

Susceptibility of mandarins and tangors to Citrus Leprosis under greenhouse conditions 

Nunes M.A. 1 , Pereira J.A. 1 , Freitas-Astua J. 2 , Novelli V.M. 1 , and Bastianel M. 1 

1Instituto Agronômico (CCSM-IAC), Centro de Citricultura Sylvio Moreira, Brazil; and 2Empresa Brasileira de Pesquisa Agropecuária 

(EMBRAPA), Cassava and Fruits, Cruz das Almas, Brazil. valdenice@centrodecitricultura.br 

Citrus Leprosis is an important disease affecting sweet oranges in Brazil, and almost all of the studies 

performed to date have included only sweet oranges. The disease is caused by Citrus leprosis virus C (CiLV-C), 

which infects several citrus and non-citrus host plants, and is transmitted by Brevipalpus phoenicis, a 

cosmopolitan and polyphagous mite. Few studies are available on the response of other citrus genotypes, 

such as mandarins and their hybrids, to Leprosis. In this work, 56 mandarin (Citrus reticulata) and five tangor 

(C. reticulata x C. sinensis) genotypes from the Citrus Active Germplasm Collection of Centro Apta Citros 

Sylvio Moreira (BAG Citros IAC) were assessed for their response to Leprosis using a score scale. Five reps of 

each genotype were infested with viruliferous mites maintained on infected sweet orange fruits. Among the 

genotypes tested, only ‘Shikai’ mandarin (accession CN 551) and ‘Dieberger 5’ (accession CV 456) did not 

present any symptoms. ‘Small-fruited 627’ mandarin (accession CN561) was the most susceptible genotype 

evaluated, with the highest average score (3.2). The average general score to all genotypes was 1.25. The 

results demonstrated that some mandarins and tangors are resistant to Leprosis, as widely reported in the 

literature. However, most genotypes exhibit differential levels of susceptibility to the virus. Financial support: 

Fapesp, CNPq and Embrapa. 


S02P11 

Development CTV resistant citrus rootstocks using hybridization 

Pinar H. 1 , Seday U. 1 , Unlu M. 1 , and Uzun A .2 

1 Alata Horticultural Research Station, Genetic and Breeding, Turkey; and 2 Erciyes University, Department of Horticulture, Turkey. 

usd75@hotmail.com 

Citrus is widely grown throughout tropical and subtropical regions of the world with 117 million tons of 

production. There are some serious problems affecting citrus production. One of them is Citrus tristeza virus 

(CTV) that is the most significant viral pathogen of citrus. This disease causes quick decline of trees grafted on 

sour orange (Citrus aurantium) rootstock. The development of CTV resistant rootstocks has become a priority 

objective of citrus breeding programs. Genetic studies revealed that CTV resistance is controlled by a single 

dominant gene in Poncirus trifoliata. Regarding resistance to CTV some molecular markers had been identified. 

Seven of them were cloned and were converted as SCARs. Three of them are SCB 11, SC007, SCTO8. In this study 

some citrus rootstocks (‘Volkameriana’, ‘Rough lemon’, ‘Cleopatra’, Citrumelo, ‘Troyer’ and ‘Carrizo’ citranges, 

‘Taiwanica’, sour orange, Yuzu, ‘Rangpur’ lime, pummelo and Fortunella spp.) and hybrids of P. trifoliata X sour 

orange were screened with the three markers at Alata Horticultural Research Station. SCT08 marker yielded 

two bands for ‘Troyer’ and ‘Carrizo’ and one band for P. trifoliata and Citrumelo. On the other hand other citrus 

rootstocks had sensitive band at 400 bp. Five of P. trifoliata X sour orange hybrids have only one resistance band 

(homozygous resistant) and 30 of them have two bands (heterozygous resistant). SCB 11, SC007 SCAR markers 

were tested at this study. This study showed that although SCB 11, SC007 SCAR markers could be use for CTV 

resistance. In the next step all materials will be evaluated by biological inoculation of plants for CTV resistance. 

S02P12 

Lime Bush (Citrus glauca) hybrids resistant to CTV 

Smith M.W., Gultzow D.L., Newman T.K., and Parfitt S.C. 

Bundaberg Research Station, Queensland Department of Agriculture, Fisheries and Forestry, Australia. malcolmsmith1966@hotmail.com 

The potential contribution of endemic Australian species to conventional citriculture has long been recognised, 

but nothing of commercial value has ever emerged. Rootstock experiments in Queensland, Australia have 

demonstrated that severe CTV reaction is their major limitation, totally masking the expression of useful traits 

these species are known to possess. In the case of Citrus glauca, the extremely slow growth of seedlings and 

cuttings during the nursery phase further prevents commercial application. A breeding program commenced 

in 2002 to address these limitations and has already developed 2nd generation hybrids of C. glauca. Obstacles 

encountered by previous breeders have been overcome by using Citrus wakonai as a bridging species, resulting 

in F1s that flower within two years, and readily hybridise with Poncirus trifoliata. F2 populations (85 hybrids) 

have been free of delayed lethality, segregate ~50:50 for CTV resistance, readily propagate from cuttings, and 

display vigour comparable with conventional citrus rootstocks. Cuttings from CTV resistant F2 hybrids will be 

deployed as rootstocks in field experiments in 2013. 

S02P13 

Determination of self-incompatibility status of some clementine (Citrus clementina) genotypes 

by histological analysis 

Aka Kacar Y. 1 , Aslan F. 1 , Eti S. 1 , Boncuk M. 1 , Simsek O. 1 , Yildirim B. 1 , Yalcin Mendi Y. 1 , Yesiloglu T. 1 , Distefano G. 2 , and La Malfa S. 2 

1 Cukurova University (Cu), Horticulture Department, Turkey; and 2 University of Catania, Dipartimento di OrtoFloroArboricoltura e 

Tecnologie Agroalimentari, Italy. ykacar@cu.edu.tr 

Most of clementine mandarins belonging to Citrus that is extremely important fruit group in the world show 

self-incompatible features as sexual. Several cultivars, characterized for high compatibility level with other 

varieties, often produce several seeds in fruits. Although seeds in mandarins-like represent a huge problem 

for citrus industry, the mechanisms related to citrus incompatibility have not been deeply investigated. In this 

study, self-compatible/incompatible status of 40 clementine mandarins located at the ‘University of Cukurova, 

Faculty of Agriculture, Tuzcu Citrus Collection’ were determined by histological analysis. For this purpose, self- 


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pollination was performed and following the self-pollination, pistil samples until the fifteenth day from the 

third day were taken at intervals of two days (3, 5, 7, 9, 11, 13, 15, 20th days after pollination). All samples fixed 

in FPA70 solution and stored at 4 °C. Pistil samples were stained with aniline blue for microscope observation. 

The preparations were observed by fluorescence microscope after staining and squashing. All pollen tubes of 

the genotypes arrested in the upper or middle part of style and none reached the base of the style. As a result 

of investigations, 40 varieties of clementines have been identified certainly as a self-incompatible. 

S02P14 

Genotyping for male sterility (MS) and MS gene mapping with RAPD markers in citrus, especially 

with precocious flowering seedlings from a cross of HY16 x grapefruit 

Dewi P.S. 1 , Wakana A. 2 , Tanimoto Y. 1 , Fujiwara Y. 1 , and Sakai K. 2 

1 Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University (Grad. School of Bioresource and Bioenvironmental 

Sciences Kyushu Uni.), Agriculture, Japan; and 2 Horticultural Laboratory, Kyushu University (Horticultural Lab., Kyushu University), 

Agriculture, Japan. p_saridewi@yahoo.com 

Seedlings from Citrus species and cultivars show precocious flowering after autumn seed germination. HY16 

is a monoembryonic and male sterile hybrid-derived from a cross of ‘Hanayu’ (Citrus hanaju) × ‘Yuzu’ (Citrus 

junos). ‘Kiyomi’ tangor (satsuma × ‘Trovita’), a male sterile and monoembryonic plant, was also used to 

determine the male sterile genotype of grapefruit. Both seed parents generated seedlings with precocious 

flowering ability. Seeds were collected in November of 2006-2011 in Fukuoka, Japan, and allowed to germinate 

in a greenhouse (>10°C). Male sterile anthers were observed in hybrid seedlings from several crosses, i.e., 

HY16 × grapefruit, (HY16 × grapefruit) × grapefruit, HY16 × ‘Ruby Blood’ orange, (HY16 × grapefruit) × ‘Ruby 

Blood’ orange, HY16 × ‘Trovita’ orange, and ‘Kiyomi’ × grapefruit. On the basis of segregation analysis for MS 

in these progenies, and on the fact that HY16 and ‘Kiyomi’ did not have cytoplasmic restoration factor R for 

MS, male sterile genotype was estimated to be ms 1 ms 1 Ms 2 ms 2 ms 3 ms 3 (R - ) for HY16, Ms 1 ms 1 ms 2 ms 2 ms 3 ms 3 

(R - ) for ‘Kiyomi’ and ms 1 ms 1 Ms 2 Ms 2 Ms 3 ms 3 or Ms 1 ms 1 Ms 2 Ms 2 ms 3 ms 3 (R ) for grapefruit with male fertile 

anthers. Here, MS is a recessive character; ms 1 and ms 2 are complementary genes with upper stream 

expression of ms 2 , and ms 3 is an epistatic gene to ms 1 and ms 2 genes. Male sterile seedlings appear when 

ms 3 is recessive homozygous (ms 3 ms 3 ) and either ms 2 or ms 1 is recessive homozygous (ms 2 ms 2 or ms 1 ms 1 ). A 

population of 101 individuals from the cross of HY16 × grapefruit was chosen for mapping of Ms genes. Using 

bulked segregant analysis with 260 12-mer oligonucleotide random primers, seven RAPD markers linked to 

Ms 1 or Ms 3 allele of grapefruit were detected and mapped. Five markers flanked at the closest 9.9cM with 

the dominant of Ms 1 or Ms 3 alleles and two markers flanked at the closest 18.6cM with the recessive of ms 1 

or ms 3 alleles. 

S02P15 

Embryological studies on ‘URS Campestre’, a new seedless orange cultivar 

Guerra D. 1 , dos Santos R.P. 2 , Montero C.R.S 3 , Schwarz S.F. 1 , and Bender R.J. 1 

1 UFRGS, Horticultural Sciences Department, Brazil; 2 UFRGS, Department of Botany, Brazil; and 3 Fepagro, Research Station Caxias do 

Sul, Brazil. rjbe@ufrgs.br 

In citrus, seedlessness is a sought-after trait. Absence of seeds is advantageous for the juice industry as well 

as is meeting consumer demands. Close to the city of São Sebastião do Caí, 70 km north of Porto Alegre, 

the capital city of the southernmost state in Brazil, a new orange cultivar was identified and selected as a 

seedless cultivar. However, the cause for the nonexistence of seeds has yet to be determined. The objective 

of the present work was to analyze reproductive flower structures such as anthers and seminal rudiments to 

determine the grounds for the absence of seeds. ÚRS Campestre´ flowers of different developmental stages 

were collected, fixed and examined. The flowers have anthers and ovaries of typical dimensions. Pollen grains 

characteristics analysis point to a standard developmental pattern, normal meiosis and high viability (84%) and 

elevated in vitro pollen tube germination rates (63%). However, so far, characteristics of generative cell and 

sperm cells have not been evaluated. Preliminary studies of seminal rudiments allowed detect abnormalities 

at the nucellus and embryo sac development, which seems to be one of the limiting causes of the fecundation 

process hindering seed production. 


S02P16 

Mechanism of seedlessness in a new lemon cultivar ‘Xiangshui’ (Citrus limon) 

Zhang S.-W., Huang G.H., Ding F., He X.-H., and Pan J.C. 

Agricultural College of Guangxi University, P.R.China. honest66222@163.com 

Seedlessness is an important economic trait of lemon. Pollen and embryo sac fertility, embryo development, 

compatibility of self-pollinated ‘Xiangshui’ lemon and cross-pollinated ‘Xiangshui’ lemon were studied for 

investigating mechanism of seedlessness in ‘Xiangshui’ lemon. The results showed that the fertility of pollen 

and mature embryo sac was normal. The development of embryo sacs belonged to polygonum type. The 

mature embryo sac had one egg, two synergids, three antipodal cells and one big central cell containing 

two polar nuclei. Pollen tube in self- or cross-pollination grew well in stigma. Pollen tube of cross-pollinated 

‘Xiangshui’ lemon could grow normally in style and ovary, and then entered into the embryo sac, double 

fertilization was accompanied. However, the growth of pollen tube in self-pollination was finally stopped in the 

bottom of stigma. Embryonic development in cross-pollination was normal. Zygote began to divide 2 weeks 

after cross-pollination (WACP). Early globular embryos were observed 3 WACP. Globular embryos and heartshaped 

embryos were observed 4 WACP. Torpedo-shaped embryos were observed 5 WACP. Cotyledonary 

embryos were observed 6 WACP and developed into complete seeds. While in self-pollination, ovules began 

to abort at 2 weeks after self-pollination (WASP), disappeared 5 WASP later and produced seedless fruits. The 

emasculated flowers without any pollination finally developed into seedless fruits also. Results indicated that 

parthenocarpy is contributed to seedlessness. However, gametophytic self-incompatibility has a main role in 

seedlessness of ‘Xiangshui’ lemon by blocking fertilization in the bottom of stigma. 

S02P17 

Differences in the genetic structure of citrus triploid hybrids recovered from 2x X 2x and 4x X 2x 

sexual hybridisations 

Aleza P. 1 , Cuenca J. 1 , Juárez J. 1 , Ollitrault P. 2 , and Navarro L. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; and 2 Centre de 

Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), BIOS, France. aleza@ivia.es 

Citrus triploid hybrids can be recovered by 2x X 2x hybridisations as a consequence of the formation of 2n 

gametes or by interploid hybridisation. Most of the 4x parents used in our program are doubled-diploid (DD), 

also known as autotetraploid. The genetic structure of diploid gametes and particularly the rate of parental 

heterozygosity restitution (PHR) depend on the meiotic process by which they were originated. Second-division 

restitution (SDR) is the 2n gamete formation mechanism involved in ‘Fortune’ and clementines. With SDR, PHR 

is positively linked with the distance of each locus to the centromere. With DD parents, PHR depends on the rate 

of preferential pairing and thus the proportion of disomic versus tetrasomic segregations. We have compared 

the genetic structure of two populations of diploid gametes of clementine (one population of 2n gametes and 

one of 2x gametes produced by DD) with SNP and SSR markers covering the 9 citrus chromosomes. The DD 

displays mostly tetrasomic segregation; however three linkage groups present intermediate segregation and 

one displays a tendency for disomy. The PHR in the 2n gametes is 2/3 of that obtained in 2x gametes produced 

by DD. The two methods of triploid production appear complementary in terms of genotypic variability. 4x X 2x 

hybridizations are more efficient than 2x X 2x for developing new cultivars phenotypically closer to the diploid 

parent of the DD. Conversely, 2x X 2x hybridisations provides a greater opportunity to select innovative products. 

S02P18 

Efficient haploid production on ‘Wilking’ mandarin by induced gynogenesis 

Jedidi E. 1 , Kamiri M. 2 , Poullet T. 3 , Ollitrault P. 3 , and Froelicher Y. 3 

1 Tunisian National Agronomic Research Institute (INRAT), Horticultural Laboratory, Tunisia; 2 Groupe Kabbage (DAK), Agadir, Morocco; 

and 3 International Center for of Agricultural Research for Development (CIRAD), UMR AGAP, France. jedidi.emy@gmail.com 

Seedlessness is a major criterion for the citrus fresh fruit market. Therefore, triploid breeding appears very 

promising for the selection of new citrus cultivars. CIRAD has developed a method to produce triploid hybrids 


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by somatic hybridization between diploid and haploid lines, and demonstrates the potential for haploid 

citrus production by induced gynogenesis in clementine. In this work we analysed the efficiency of induced 

gynogenesis by irradiated pollen in ‘Wilking’ mandarin (Citrus reticulata). Five doses of gamma irradiation 

of ‘Meyer’ lemon pollen were tested (0, 150, 200, 250, 300 Grays). Embryos were extracted from small 

seeds, obtained in immature fruits, and cultivated in vitro. The ploidy level of plantlets was determined by 

flow cytometry analysis. Irradiated pollen appeared to be efficient for gynogenesis induction in ‘Wilking’. A 

relatively high number of haploids (7 plantlets) were obtained, essentially after hybridisation with ‘Meyer’ 

lemon pollen irradiated at 250 Grays. The ploidy level of all haploid plantlets was confirmed by chromosome 

counts, and molecular markers demonstrated their gynogenetic origin. These haploid lines should be useful 

for triploid breeding by somatic hybridisation, and also constitute interesting resources for genomic studies. 

S02P19 

Differences in ploidy levels of interploidal crosses progenies between diploids and tetraploid 

somatic hybrids in citrus 

Kamiri M. 1 , Srairi I. 1 , Poullet T. 2 , Ollitrault P. 2 , and Froelicher Y. 2 

1 Domaines Abbes Kabbage (DAK), Morocco; and 2 Centre de Coopération Internationale en Recherche Agronomique pour le 

Développement (CIRAD), UMR AGAP, France. kamirimourad@hotmail.com 

One of the main objectives of citrus breeders is to obtain sterile mandarins that produce seedless fruits. Triploids 

are a response to these criteria. A way for triploid creation is sexual crosses between diploids and tetraploids. 

However, the scarcity of the natural tetraploid gene pool has been a restriction for using this method. Citrus 

somatic hybridisation via protoplast fusion allowed the creation of allotetraploid somatic hybrids that can 

be used as parents to generate triploid cultivars. Several crosses using diploids (female) and allotetraploid 

somatic hybrids (male) were conducted by CIRAD: a) ‘Fortune’ mandarin x (‘Willow leaf’ mandarin ‘Star Ruby’ 

grapefruit tetraploid somatic hybrid); b) ‘Eureka’ lemon x (‘Star Ruby’ grapefruit ‘Corsican’ citron tetraploid 

somatic hybrid); and c) ‘Eureka’ lemon x (‘Mexican lime’ ‘Shamouti’ orange tetraploid somatic hybrid). The 

majority of progenies were triploid from the 3 crosses (61-76%). However diploid and tetraploid progenies 

were also obtained in all of them. Molecular analysis of progenies with SSR markers revealed that tetraploids 

were issued from a diploid male gamete and an unreduced female gamete, while diploids could be issued 

from a haploid ovule and a haploid male gamete. This study reveals that ploidy variations were owed to 

meiotic dysfunction of either the tetraploid somatic hybrids or the diploid female parent. 

S02P20 

Gametic configuration and inheritance of SSR markers in tetraploid interspecific and intergeneric 

citrus somatic hybrids 

Kamiri M. 1 , Stift M. 2 , Srairi I. 1 , Chahidi B. 1 , Poullet T. 3 , Costantino G. 4 , Dambier D. 3 , Ollitrault P. 3 , and Froelicher Y. 3 

1 Domaines Abbes Kabbage (DAK), Morocco; 2 University of Konstanz, Ecology, Department of Biology, Germany; 3 Centre de coopération 

internationale en recherche agronomique pour le développement (CIRAD), UMR AGAP, France; and 4 Institut national de recherche 

agronomique (INRA), UR1103 Génétique et Ecophysiologie de la Qualité des Agrumes, France. kamirimourad@hotmail.com 

Citrus somatic hybridization has become an integral part of citrus improvement programs worldwide. More than 

100 somatic hybrids have been created by CiRad. Intra and interspecific somatic hybrids will be used mostly for 

the triploid scion breeding. Intergeneric somatic hybrids can have a direct application as rootstocks or be used 

as parents for sexual ‘tetrazyg’ breeding. To optimize the design of such breeding schemes, it is essential to have 

knowledge of the inheritance mode in such allotetraploid hybrids. The aim of the present study was to investigate 

the inheritance (disomic, tetrasomic or intermediate) in a citrus interspecific hybrid (Citrus reticulata x Citrus limon) 

and an intergeneric somatic hybrid (C. reticulata x Poncirus trifoliata). Two triploid populations were generated 

using the somatic hybrids as pollinators in crosses with the diploid ‘Chandler’ pummelo. The triploid progenies 

were genotyped with SSRs to infer the allelic constitution of the somatic hybrid gametes. A likelihood-based 

approach was used to estimate for each locus the proportion of disomic versus tetrasomic segregations. For the 

two somatic hybrids, intermediate inheritance was observed with a major tendency for tetrasomic segregation 

in the interspecific hybrid, but a tendency for disomic inheritance in the intergeneric hybrid. The implications of 

the observed inheritance mode for citrus breeding are discussed with special focus on heterozygosity restitution. 


S02P21 

Haploid and polyploid hybrids obtained from cross of diploid citrus 


Horticulture Research Institute, Sichuan Academy of Agricultural Sciences (HRI,SAAS), Centre of Fruit Reseach, China. 

sc.liujianjun@163.com 

Ploidy breeding is an effective and economical method in citrus to create seedless cultivars. Haploid, triploid and 

tetraploid hybrids were obtained and evaluated in our cross-breeding program. ‘Tangor 15-1’, a selection of local 

natural hybrid of Citrus reticulata × Citrus sinensis, was used as a female parent to cross with ‘Red Tangerine’ (C. 

reticulata) in 2000. Both parents are diploid. The obtained seeds were sowed in 2001 and seedlings began to 

flower and fruit successively since 2005. Traits of the seedlings were evaluated. During the evaluation process 

four seedlings were suspected to be variant for ploidy level. Further identification was performed by chromosome 

count and flow cytometry. Identification confirmed that one seedling was haploid, which was weak in growth 

with very small and long-shaped leaf; one was tetraploid, which was strong in growth with thick and dark-green 

leaf; the other two were triploid, which were strong in growth with seedless fruit. Bud sticks of these plants were 

taken for propagating conservation in the breeding nursery, and the biological/botanical characteristics of these 

haploid and polyploid plants were recorded and their fruit quality were analyzed. The tetraploid hybrid has been 

used as a new male parent in our subsequent breeding program. 

S02P22 

Chromosome redundancy and phenotypic variation in autotetraploid trifoliate orange seedlings 

Oh E.U. 1 , Chae C.W. 2 , Kim S.B. 1 , Park J.H. 1 , Yun S.H. 2 , Koh S.W. 2 , and Song K.W. 1 

1 Jeju National University (JNU), Faculty of Bioscience and Industry, Korea; and 2 National Institute of Horticultural and Herbal Science 

(NIHHS), Citrus Research Station, Korea. kwansong@jejunu.ac.kr 

The study was conducted to evaluate the phenotypic variation in autotetraploid seedlings occurred spontaneously 

from diploid trifoliate orange (Poncirus trifoliata). Tetraploid nucellar seedlings were selected by flow cytometry 

and then ploidy level without aneuploid was confirmed by chromosome analysis. These young tetraploid seedlings 

were transplanted in open field and phenotypic variation such as tree vigor, growth habit, and photosynthesis 

activity was investigated. Tree vigor such as tree height, trunk diameter, internode length, and thorn length varied 

at juvenile stage. Specially, distinctively morphological difference was observed in growth habit including branch 

number and branching angle. Also, there was variation in photosynthesis activity such as leaf size, stomata density, 

photosynthesis rate, and chlorophyll index (SPAD value). These phenotypic variations had no correlation among 

phenotypic traits. The effect of chromosome redundancy on phenotypic variation was analyzed by karyotyping 

chromosomes with chromomycin A3 (CMA) staining and analyzing DNA methylation level. The results indicated 

that phenotypic variations of autotetraploid seedlings might be related to epigenetic effect. 

S02P23 

New cybrids resulting from asexual pathway: a promise of the cybridization for creating new 

rootstocks and varieties 

Dambier D., Petit F., Barantin P., and Ollitrault P. 

Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), France. 

dominique.dambier@cirad.fr 

Different breeding strategies have been developed by CiRad to overcome agronomic and economical issues of 

the citrus industry in intertropical, subtropical and Mediterranean conditions. The present work is focused on the 

selection of new cybrids through different approaches of protoplast fusion. Two main objectives were targeted: 

(i) the manipulation of the nucleocytoplasmic male sterility in the framework of our seedless mandarin breeding 

project and (ii) the development of ‘Rangpur’ lime and ‘Rough’ lemon lines tolerant of Alternaria. 22 diploid 

cybrids have been obtained by targeted cybridization or as by-products of symmetric somatic hybridization, 

from interspecific and intergeneric combinations. For targeted cybridization, 4 genotypes ‘Eureka’ lemon, 

‘Volkamer’ lemon, ‘Rough’ lemon and ‘Boukhobza’ orange, were combined via the cytoplasts method with ‘Star 


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Ruby’ grapefruit callus-derived cytoplasts. These combinations regenerated some diploid and tetraploid cybrids. 

The nuclear origin was confirmed by SSR markers to have arisen from the leaf-derived parent, while universal 

chloroplastic and InDel PCR markers exhibited respectively random chloroplast segregations but systematic 

inheritance of grapefruit mitochondria. The analysis of nucleocytoplasmic interaction should open in the near 

future a new pathway for rootstock improvement and sterility management for new seedless cultivar breeding. 

S02P24 

Several seedless citrus hybrids selected from tangor x ‘Ponkan’ cross 


Horticulture Research Institute, Sichuan Academy of Agricultural Sciences (HRI,SAAS), Centre of Fruit Reseach, China. 

sc.liujianjun@163.com 

Seedlessness is important for the consumption and marketing of fresh citrus fruit. ‘Ponkan’ (Citrus reticulata) 

is easy to peel and has excellent inner quality, but many ‘Ponkan’ cultivars in China are seedy (13~14 seeds 

per fruit). The goal of this breeding program is to breed new cultivars with the advantages of ‘Ponkan’ and less 

seeds. In 2000, ‘Ponkan’ was used as male parent to cross with ‘tangor 15-1’, a selection of local natural hybrid 

(C. reticulata × C. sinensis). ‘Tangor 15-1’ produces big fruit without seeds, deep orange-red rind, reddish 

albedo without cracks, and ‘Ponkan’ produces fruit with light orange rind, white albedo with cracks. The 

obtained seeds were sowed in 2001 and seedlings began to flower and fruit successively since 2005. Traits 

of the seedlings were evaluated. Six seedlings were found to be seedless or low seed. All of these six plants 

produced fruits of big size, but the color of rind and albedo as well as albedo crack, looked more like ‘Ponkan’. 

The average seed numbers per fruit of six hybrids were 2.45, 2.86, 3.33, 4.33, 1.4 and 3.0. The biological/ 

botanical characteristics of these hybrid plants were recorded and their fruit quality was analyzed for 3 years. 

Preliminary observations show that some of them are promising for the citrus industry. 

S02P25 

New citrus hybrids: selection and genetic studies 

Novelli V.M., Bastianel M., Fernandes K.A., Misságlia J., Latado R.R., Cristofani-Yaly M., and Machado M.A. 

Instituto Agronomico - Centro de Citricultura Sylvio Moreira (IAC-CCSM), Brazil. valdenice@centrodecitricultura.br 

The tools of biotechnology have enabled the improvement of citrus with significant reduction in cycle 

identification and selection of new materials, considering that the genetic studies and breeding in Citrus sp. 

sometimes has been hampered because of characteristics related to the reproductive biology of these species, 

i.e. high interspecific fertility, apomictic reproduction, polyembryony, a long juvenile phase and others. The 

Centro de Citricultura Sylvio Moreira-IAC has a breeding program for generating populations of scions and 

rootstocks hybrids. Phenotypic evaluations and genetic studies are underway to select promising materials, 

mainly for resistance to major diseases of citrus. The objectives of this study were to identify triploid plants 

and to construct genetic map with molecular markers using a backcrossing population of TMxLP163 (‘Murcott’ 

tangor x ‘Pêra sweet’ orange), a hybrid pre-selected in the breeding program, crossed with ‘Pêra April’ orange. 

Of the approximately 700 plants evaluated, 66 triploid (9.1%) were identified by flow cytometry . We evaluated 

239 microsatellite loci, developed from EST library and 34 (14,2%) loci were selected with potential for genetic 

mapping. With this work, we expect to obtain new combinations resistant to Citrus Variegated Chlorosis (CVC) 

and with excellent fruit characteristics for the juice industry. Financial support: FAPESP, CNPq, INCT-Citros. 

S02P26 

Characterization of fruits of hybrids between ‘Sunki’ mandarin (Citrus sunki) and Sour orange 

(Citrus aurantium) 

Schinor E.H., Michielin T.H.V., Simonetti L.M., Cristofani-Yaly M., Pompeu Jr. J., And Bastianel M. 

Centro Apta Citrus Sylvio Moreira/IAC, Brazil. evandro@centrodecitricultura.br 

The Centro de Citricultura Sylvio Moreira, Instituto Agronômico, since 1990, has been developing a breeding 

program of rootstocks, via hybridization, aiming to increase the number of varieties used in Brazilian citriculture 

and to improve the genetic variability as a way to overcome biotic and abiotic problems. In this work, we have 


agronomically characterized 79 hybrids from reciprocal crosses between ‘Sunki’ (Citrus sunki) (TS) and sour orange 

(Citrus aurantium) (LA). Fifteen fruit of each hybrid were evaluated for the following characteristics: mass (M), 

height (H), diameter (D) and number of viable (SV) and aborted seeds (SA) per fruit, and the number of embryos 

of the seeds. The experimental design was a randomized complete block with fifteen repetitions. The averages of 

the variables were subjected to analysis of variance by F test and the comparison of the means made by the Scott 

Knott parametric test. There were differences among hybrids for all traits. The (M) of the fruits ranged from 28.2 to 

116.7 g and (H) and (D) ranged from 3.03 to 5.92 cm and 1.21 to 7.57 cm, respectively. The fruits presented up to 

22 (SV) and 1-18 (SA). The fruits of the hybrid TSxLA 7010 did not show (SV). The viable seeds showed 1-6 embryos. 

The results obtained for the characteristics evaluated showed that there was great variability among the hybrids. 

S02P27 

Evaluation of clementine x ‘Kara’ mandarin hybrids 

Seday U. 1 , Kafa G. 1 , Uysal O. 1 , Polatoz S. 1 , Uzun A. 2 , and Gulsen O. 2 

1 Alata Horticultural Research Station, Mersin (AHRS), Turkey; and 2 Erciyes University Department of Horticulture, Kayseri (EUDH), 

Turkey. usd75@hotmail.com 

Mandarin is one of the most important citrus species and has been subject of breeding research to obtain 

new cultivars by hybridization. Mandarin breeding program has been continued for a long time in Alata 

Horticultural Research Station, Mersin, Turkey. In the program, a lot of cultivars have been used as parents. 

We report here the results obtained by crossing mono embryonic clementine and late maturing ‘Kara’ 

mandarin. One hundred -twenty hybrids were evaluated for their fruit characteristics and 25 fruits per tree 

for four years were examined. We found a high level of variation in fruit parameters between hybrids. Fruit 

weight of hybrid plants ranged between 44-231 g. Seed number of hybrids varied from 3.85 to 45.80 whereas 

juice content ranged between 13.6% and 61.0%. According to four years of observation the harvesting period 

of hybrids extended from mid-October to end-February. Some promising hybrids were selected due to their 

good fruit quality. ‘9-16’ hybrid was selected because of its large fruit size (168 g), early maturity and easy 

peeling features. On the other hand, ‘10-26’ hybrid was superior with large fruits size (178 g), higher juice 

content (61%) and late maturity. Results of this study showed that increasing of fruit quality and extending 

maturity time of mandarin are possible using conventional hybridization methods. 

S02P28 

Distribution of leaf features in citrus hybrids obtained from clementine 

Uysal O., Kafa G., Seday U., and Polatöz S. 

Alata Horticultural Research Station, Turkey. onuruysal33@gmail.com 

In this study, leaf length, leaf width and petiole wings dispersion were investigated in 41 hybrids obtained 

from clementine and ‘Minneola’ tangelo. Measurements were carried out using 40 leaves derived from 

all sides of four years plants. Clementine leaf length and width were 108.7 mm and 37.1 mm respectively 

whereas they were 107.8 mm and 51.3 mm respectively for ‘Minneola’ tangelo. The leaf length of hybrid 

plants varied between 72.5 mm and 144.0 mm. For forty-one hybrid plants the distribution of leaf length was 

as follows: 72.5-85.0 mm (14.63%), 85.0-100.0 mm (51.22%), 100.0-115.0 mm (19.52%), 115.0-145.0 mm 

(14.63%). Most of hybrids had lower leaf length than clementine and ‘Minneola’. Leaf width varied between 

24.0 mm and 50.1 mm among the hybrids with the following distribution: 2.4-3.0 mm (7.32%), 3.0-4.0 mm 

(60.97%), 4.0-5.1 mm (31.71%). Therefore leaf width, in hybrids mostly came from clementine mandarin. 

Petiole wings were observed in 36 of 41 plants. 

S02P29 

Optimal dose of gamma irradiation for mutation induction in mandarins 

Handaji N. 1 , Benyahia H. 1 , Arsalane N. 1 , Mouhib M. 2 , Ibriz M. 3 , Srairi I. 4 , Chahidi B. 4 , and Bourachde Y. 4 

1 Institut National de la Recherche Agronomique Kenitra (INRA), Morocco; 2 Institut National de la Recherche Agronomique Tanger (INRA), 

Morocco; 3 Universite Bn Toufail Faculte de Sciences Kentra, Morocco; and 4 Domaine Kabbage Agadir, Morocco. citrusinra@yahoo.fr 

A new program of irradiation was carried out by INRA Morocco to develop seedless fruits of existing citrus 

varieties. A first experiment was established to determine the optimal dose range of gamma source radiation 


S02

S02 

for mutagenic induction on the mandarins ‘Anana’, ‘Vietnam’ and ‘Kara’. Seeds, budwood and seedlings were 

irradiated with a 6o Co gamma source with five doses (25Gy, 30Gy, 50Gy, 70Gy, 90Gy). No significant difference 

in radio sensitivity was observed between varieties depending on the dose of treatment. Single dose 90Gy 

caused the decrease of buds viability. Peeled seed showed no differences in radio sensitivity. Some stimulation 

of germination rate and early growth was observed with low doses. The LD 50 for seedlings was between 70Gy 

and 90Gy. Field evaluation of the obtained mutants is currently performed in Kabbage domain. 

S02P30 

Effect of budwood irradiation on seed number of clementine, ‘Nova’ and ‘Robinson’ mandarins 


Alata Horticultural Research Station Mersin (AHRS), Turkey. gucerkafa@gmail.com 

We have investigated the effect of budwood irradiation on seed number of clementine, ‘Nova’ and ‘Robinson’ 

mandarin derived mutant populations. A total 675 plants issued from budwood irradiation and 10 nonirradiated 

plants of each parental variety as controls were planted in the field. For two years, seed number of 

135 clementine mutants, 110 ‘Nova’ mutants, 165 ‘Robinson’ mutants and control plants were determined. 

Clementine mutant plants average seed number was 15.22 for 30 gray, 18.43 for 50 gray and 18.28 for nonirradiated 

in 2010. ‘Nova’ mutant plants average seed number was 8.25 for 30 gray, 7.36 for 50 gray and 18.38 

for non-irradiated in 2010. ‘Robinson’ mutant plants average seed number was 10.75 for 30 gray, 11.76 for 50 

gray and 23.66 for non-irradiated in 2010. Clementine mutant plants average seed number was 17.10 for 30 

gray, 17.19 for 50 gray and 17.54 for non-irradiated in 2011. ‘Nova’ mutant plants average seed number was 

11.01 for 30 gray, 15.53 for 50 gray and 18.61 for non-irradiated in 2011. ‘Robinson’ mutant plants average 

seed number was 11.32 for 30 gray, 12.11 for 50 gray and 22.38 for non-irradiated in 2011. As a result budwood 

irradiation decreases seed number in resulting mutant plants, especially for ‘Nova’ and ‘Robinson’ mandarins. 

S02P31 

Three variegated clementines 


Alata Horticultural Research Station Mersin (AHRS), Turkey. gucerkafa@gmail.com 

Three variegated clementine mutants among the M1V3 clementine plants were selected at the Alata 

Horticultural Research Station of Mersin. Three variegated clementine mutants obtained from budwood 

irradiation of 30 gray Gamma ray. Young fruit rind color attractively variegated but fruit rind color variegation 

fades with maturity and mature fruit rind color could easily masquerade as an ordinary clementine. The young 

fruit rind is striped green and orange, but mature fruit rind has ridges. Seed number is 7.5 for variegated 

clementine No.1, 13.07 for variegated clementine No.2, 11.94 for variegated clementine No.3 and 17.54 for 

control clementine plants. Fruit weight are 72.73 g for variegated clementine No.1, 69.27 g for variegated 

clementine No.2, 80.94 g for variegated clementine No.3 and 110.10 g for control clementine plants. Other 

pomological characteristics are as same variegated and control plants. 

S02P32 

New low seeded mandarins (Citrus reticulata) and lemons (Citrus lemon) selections obtained by 

gamma irradiation in Chile 

Montañola M.J., and Martiz J. 

Pontificia Universidad Católica de Chile (PUC), Facultad de Agronomíe e Ingeniería Forestal, Departamento de Fruticultura, Chile. 

mmontano@uc.cl 

Gamma irradiation of buds is a technique that has been successfully used in citrus breeding programs that 

seek to remove seeds from fruits. In 2007, Pontificia Universidad Católica de Chile CITRUS lab started a new 

breeding program of mandarins and lemons using this technique. Irradiated buds were grafted and plants 

were grown in a commercial nursery. In 2009, a field trial was established with 4500 hybrid mandarins, 1200 

clementines and 2500 lemons, in Pomaire, Chile (33°39’S, 71°10’W). First evaluation of fruit was made in 


2011. Early production was achieved by the use of high density planting, minimal pruning managements, 

fertirrigation and enhancement of cross pollination using 10 to 12 hives/ha. After 2 harvest seasons, most 

phenotypical variations have been observed in lemons, obtaining 164 seedless selections, 4 thornless 

selections and a compact selection interesting for ornamental production. In the case of mandarins 316 

plants have been described as low seeded and 14 were completely seedless. Techniques used in this program 

allow shortening in 5 years the time spent obtaining new citrus varieties. The stability of mutations detected 

is being evaluated and new commercial field trials will be established with the selected materials. 

S02P33 

Radiosensitivity of seeds and nodal segments of citrus rootstocks irradiated in vitro with γ-rays 

from 60Co Tallón C.I., Porras I., and Perez-Tornero O. 

Instituto Murciano de Investigación y Desarrollo Agrario y Alimentario (IMIDA), Citricultura, Spain. olalla.perez@carm.es 

The first step for a breeding program through physical mutagenesis by radiation is the evaluation of the sensitivity 

in the plant material. Seeds of Citrus aurantium and Citrus macrophylla and nodal segments, where the buds 

were completely removed, from micropropagated explants of C. macrophylla, were used to determine their 

radiosensitivity to gamma radiation. A 60 Co source of γ-rays was used to deliver doses of 0, 10, 20, 30, 40 y 50 

Gy for nodal segments, or between 0 and 250 Gy for seeds. After irradiation, the loss of germination percentage 

or organogenesis efficiency was measured over two consecutive culture periods and the dose resulting in a 

50% loss in germination or regeneration frequency was computed as the LD50 value. For nodal segments of C. 

macrophylla, the LD50 was determined as 29.2 Gy. Seeds of sour orange were the least sensitive to radiation, its 

LD50 was determined at a dose of 155.6 Gy while the LD50 in seeds of C. macrophylla was of 129 Gy. 

S02P34 

Studies on mutation breeding for seedless and low-seeded cultivars of citrus 

Tang X.L., and Ma P.Q. 

Institute of Fruit Tree Research of Guangdong Academy of Agricultural Sciences, Key Laboratory of South Subtropical Fruit Biology and 

Genetic Resource Utilization, Ministry of Agriculture, China. tangxlgaas@21cn.com 

Mature autumn shoots were taken from the adult seedy ‘Nianju’ (Citrus reticulata) and ‘Luogangtiancheng’ (Citrus 

sinensis) trees and then the leaves of the shoots were stripped. The shoots were irradiated with gamma rays 

from 60 Co at the doses of 0, 4, 6 and 8 Kr with the dose rate of 230 r/min in January of 2005. All the treated buds 

were single-bud-grafted on ‘Hongningmeng’ (Citrus limonia) rootstocks after irradiation treatment. The survival 

rates were 93.2%, 68.4%, 41.3% and 16.5% for the 0, 4, 6 and 8 Kr treatment of ‘Nianju’, and 98.9%,84%,73% 

and 57.1% of ‘Luogangtiancheng’, respectively. The plantlets were grown in the orchard in May of 2006. Through 

fruit investigation for 2 years, 4 low-seeded mutants (4-10, 6-11, 6-6, 3-11) with good characters of ‘Nianju’ 

were screened and their seed contents were 3.3-6.6 seeds/fruit, which were remarkably less than 17.6 seeds/ 

fruit of the control. In the meanwhile, 4 commercial seedless mutants (5-2-1. 7-1-5, 7-3-1, 7-3-8) with good 

characters of ‘Luogangtiancheng’ were screened and their seed contents were 1.1-2.7 seeds/fruit, which were 

obviously less than 13.5 seeds/fruit of the control. The pollen alive rates and the pollen germination rates of the 

seedless and low-seeded mutants were obviously lower than their control respectively. One of the main causes 

producing seedless and low-seeded fruits was higher rate of pollen abortion. 

S02P35 

Agronomic performance of twenty six clones of ‘Pera’ sweet orange in São Paulo state, Brazil 

Carvalho S.A., Latado R.R., Silva L.F.C., and Müller G.W. 

Instituto Agronômico (IAC), Centro de Citricultura Sylvio Moreira, Brazil. sergio@centrodecitricultura.br 

‘Pera’ sweet orange, one of the most important Brazilian citrus varieties, is highly susceptible to Citrus 

tristeza virus (CTV), causing reduced yield and fruit quality, even on tolerant rootstocks. The ‘Pera’ IAC 


S02

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clone, preimunized with “PIAC” mild protective CTV isolate, is the most widespread, but several other 

clones derived from spontaneous mutations have been selected. In order to define the best ‘Pera’ sweet 

orange clones for each environmental condition, the agronomic performance of 26 clones was evaluated 

in 9 experiments carried out in three regions of the São Paulo state: Northern, Central and Southern, 

among which there is a temperature gradient decrease. The experiments were established as randomized 

blocks with one plant per plot and ten repetitions. Results from 10 to 17 years of evaluation show that 

genetic differences between clones reflect on growth, production and interaction with the climate and 

CTV. Natural breakdown in protection by severe CTV isolates in clones preimmunized with “PIAC” occurred 

in colder climates, even in vigorous clones such as IAC 2000, indicating the need of further studies for 

effective cross protection. The best clones for the Southern region are IAC 2000, Bianchi, IAC and EEL, but 

Olimpia and Ipiguá are not recommended. For the Central region, recommended clones include IAC 2000, 

Bianchi, IAC, EEL and Olimpia. These clones are also recommended to the Northern and warmer regions, 

with the exception of IAC 2000 that exhibits excessive vegetative growth, delaying the first commercial 

productions. 

Financial support: CNPq, FAPESP and Fundag 

S02P36 

Distribution of fruit characteristics in the group of citrus Setoka nucellar seedlings 

Park J.H., Yun S.H., Koh S.W., and Chae C.W. 

Citrus Research Station (CRS), National Institute of Horticultural & Herbal Science RDA, Korea. jeju4444@korea.kr 

‘Setoka’ tangor was developed at Fruit Research Institute in Japan. This variety has top fruit quality and 

also shape is graceful oblate. No seed is in it. The strategies of the breeding for nucellar progenies might 

be targeted for the early mature type, vigor, and improvement of fruit quality. We worked for the new 

nucellar breeds with the excellent fragrance better than the ‘Setoka’ tangor. In 2004, we obtained seeds 

from the hybridization by seed parent tangor and pollen parent ‘Orlando’ or Citrus Natsudaidai. In 2011, 

we analyzed and classified them using the data of main fruit trait in 150 flowered progenies. The average 

fruit fresh weight was 236g and peel thickness was approximately 2.8mm. Sugar content per fruit indicated 

14.3°Brix and acid content was 1.49%. Sugar/acid ratio was 9.92. The highest frequency was 31.3% with 

the 14.1 ~ 15.0 °Brix of seedlings. Especially, excess of 16 °Brix progenies occupied the 9.4 percentage. 

Seedlings with 1.31 to 1.50% of acid content took up 28 percentage, following an 1.11 to 1.30%, 1.51 to 

1.70% range, respectively. On the correlation between fruit weight and both °Brix and acidity, the greater 

fruit fresh weight tended to be the lower sugar and acid content in fruit. In the relation between °Brix and 

acidity, the sugar content in fruit tended to increase the acid content of the fruit. On the other hand, this 

tendency was not affect by the pollen genitors. In fruit quality of certain citrus, the desirable sugar/acid 

ratio is 13.0 referred to more than 13 °Brix and 1% or so. From the above results to develop new varieties 

of late matured citrus, the higher °Brix of nucellar seedlings might be selected carefully, we proved that 

the higher sugar content tended to increase the higher acid content of fruit in case of nucellar seedlings. 

We suggested that the selection of promising nucellar variety may be considered the profitable sugar/acid 

ratio by the seasonable analysis. 

S02P37 

‘Qing-ougan’: The green-peel mandarin mutation of ‘Ougan’ in Zhejiang province, China 

Xu J.G. 1 , Ke F.Z. 2 , and Huang J.Z. 3 

1 Zhejiang Citrus Research Institute (ZCRI), Research, China; 2 Zhejiang Branch for National Center for Citrus Variety Improvement 

(ZBNCCVI), Research, China; and 3 Ouhai Agriculture, forestry and fisheries Bureau of Wenzhou city (OAFFB), Extension, China. 

xujg@mail.zaas.ac.cn 

‘Ougan’ (Citrus suavissima) is a very special variety of mandarin in Wenzhou city, Zhejiang province, China. 

‘Qing-ougan’ mandarin is a mutation of ‘Ougan’ that maintains green peel even after fruit reach maturity. 

The first trees discovered were found in Ouhai District of Wenzhou city in 2001. ‘Qing-ougan’ mandarin 

has the same or very similar characters of tree, leaves and flowers with other ‘Ougan’ selections, which 


are vigorous with nearly round-shaped fruit, high yields and good storage quality. The length of shoots, 

thorns and petals is longer than with other clones. The average fruit weight is about 130 g, much smaller 

than ‘Ougan’, rind thickness is 3.8 mm, thinner than ‘Ougan’, and the edible rate is 69.9%, significantly 

higher than common and seedless ‘Ougan’. The total soluble solids of fruit juice is 9.5%, lower than other 

clones. Both of the content of total acidity and Vitamin C do not differ significantly with other clones of 

‘Ougan’. The fruit shape of ‘Qing-ougan’ is depressed at the stalk end, but the common ‘Ougan’ is usually 

slightly rounded. ‘Qing-ougan’ can maintain green peel up to the following March under common storage 

conditions, but color can change under ethylene ‘de-greening’ treatment. This indicates some chlorophyll 

degradation. For these reasons, ‘Qing-ougan’ could be an important germplasm material for breeding and 

genetic studies. 

S02P38 

Hybridization-based citrus breeding program in Turkey 

Uzun A. 1 , Gulsen O. 1 , Seday S. 2 , and Kafa G. 2 

1Erciyes University, Department of Horticulture, Turkey; and 2Alata Horticultural Research Station, Genetics and Breeding, Turkey. 

aydinuzun@erciyes.edu.tr 

Breeding studies to develop new cultivars in citrus have been carried out using traditional methods, such as 

selection, mutation and hybridization. We have carried out in Turkey a mandarin breeding program based on 

hybridization for the last ten years. Clementine mandarin was used as maternal parent and many cultivars 

from several species were used as male parents. So far, over 4000 hybrids have been already evaluated. Up 

to now several promising hybrids with different characteristics have been selected. The genotype ’33-6’ from 

a clementine X ‘Orlando’ tangelo cross is the most promising one, with large fruit (175 g) and dark orange 

rind color and it exhibits early maturity (October). The hybrid genotype ’20-2’ from a clementine X ‘Valencia’ 

orange cross was found to be late maturing (April) and it has large fruits and good appearance. A hybrid 

from a clementine x ‘Cocktail’ grapefruit, ’39-9’ cross has very large fruit (244 g) with attractive shape and it 

is harvested in November. ‘CO-44’, from a clementine X ‘Orlando’ tangelo cross has large (167 g) and early 

maturing fruit (October). In addition to these hybrids, many genotypes with good characteristics are also 

being selected. In the near future the new superior cultivars will be released. 

S02P39 

‘BATEM Fatihi’: A New Orange Selection from cv. ‘Washington’ navel 

Eryılmaz Z. 1 , Dal B. 1 , Tuncay M. 2 , Balkılıç R. 3 , and Gübbük H. 3 

1Batı Akdeniz Agricultural Research Institute (BATEM), Fruit Research, Turkey; 2Retired agricultural engineer; and 3University of 

Akdeniz, Faculty of Agriculture, Department of Horticulture, Turkey. zeyneper07@gmail.com 

Citrus variety improvement programme has been continuing in Turkey during last 30 years. During the 

period 1979 to 1983, a total 42 promising genotypes grown in different citrus locations and that have better 

earliness, yield and quality characteristics from main cultivars ‘Washington’ navel has been selected. An 

adaptation parcel was established with these selected types in 1991 in Antalya. After a long term evaluation, 

4 promising types were determined and 2 of them has been registered in 2011 as new orange cultivars. 

One of the registered cultivars named as ‘BATEM Fatihi’ has been compared with cv. ‘Washington’ navel in 

terms of maturation time, yield and quality characteristics. The results of the study showed that cv. ‘BATEM 

Fatihi’ has better fruit and tree characteristics such as earlier harvest, compact growth habit, higher yield 

capacity and bigger fruit, thinner peel, higher juice yield and soluble solid content than cultivar ‘Washington’ 

navel. The fruit maturation time was second week of November for cv. ‘BATEM Fatihi’ and the first week od 

December for cv. ‘Washington’ navel. The yield per tree was recorded as 120 kg for cv. ‘BATEM Fatihi’ and 80 

kg for cv. ‘Washington’ navel. The peel thickness, soluble solid content and fruit juice yield were 5.49 mm, 

10.62% and 49.57% for cv. ‘Washington’ navel and these values were 5.07 mm, 10.57% and 49.57% in cv. 

‘BATEM Fatihi’, respectively. 


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S02P40 

A new orange cultivar ‘BATEM Bahari’ selected from cv. ‘Valencia Late’ 

Eryılmaz Z. 1 , Ercişli S. 2 , Gübbük H. 3 , and Tuncay M. 4 

1 Batı Akdeniz Agricultural Research Institute (BATEM), Department of Fruit Research, Turkey; 2 Ataturk University, Faculty of Agriculture, 

Department of Horticulture, Turkey; 3 Akdeniz University, Faculty of Agriculture, Department of Horticulture, Turkey; and 4 Retired 

agricultural engineer. zeyneper07@gmail.com 

In this study, we aimed to select promising higher yield and quality orange types from ‘Valencia Late’ orange 

cultivars grown in different parts of Mediterranean region. The selection studies were done between 1979 

and 1983 and a total 13 promising types were selected from cv. ‘Valencia Late’ in different locations. An 

adaptation parcel was established with these selected types in 1991 in Antalya. Long term evaluation were 

done on these 13 types and among them 3 types were found more promising and one of them registered as 

new orange cultivar under the name ‘BATEM Baharı’ in 2011. In this study, some fruit and yield characteristics 

of this new cultivar were compared with original cv. ‘Valencia late’. ‘BATEM Baharı’ had lower seeds, thinner 

shell and higher juice yield. Average fruit weight, shell thickness, juice yield were 204,17g, 5,16 and 48,11% in 

cv. ‘Valencia Late’ and these values were 229,25 g, 4,41 and 58,80% in ‘BATEM Baharı’. 


Session 03 

CITRUS GENOMICS 

S03

S03O01 

Genome sequence analysis and comparisons reveal ancestral hybridization and admixture events 

in the origins of some citrus cultivars 

Gmitter Jr. F.G. 1 , Ollitrault P. 2 , Machado M.A. 3 , Reforgiato Recupero G. 4 , Talon M. 5 , Roose M.L. 6 , Navarro L. 7 , Wu G. 8 , 

Jaillon O. 9 , Morgante M. 10 , and Rokhsar D.S. 9 

1University of Florida - Citrus Research and Education Center, USA; 2CIRAD, France; 3Centro APTA Sylvio Moreira, Instituo Agronômico, 

Brazil; 4C.R.A.-Istituto Superiore per l’Agrumicoltura, Italy; 5IVIA, Centro de Genomica, Spain; 6University of California at Riverside, 

Department of Botany and Plant Sciences, USA; 7IVIA, Centro de Protección Vegetal y Biotecnología, Spain; 8USDOE, Joint Genome 

Institute, USA; 9Genoscope - CNS, France; and 10University of Udine, Istituto di Genomica Applicata, Italy. fgmitter@ufl.edu 

Since its inception, the International Citrus Genome Consortium (ICGC) has pursued development of freely 

available genomics resources and tools for the benefit of the citrus research community; these efforts 

were conducted by citrus scientists in concert with researchers from some of the world’s major genome 

sequencing centers and corporations. An early ICGC goal was to produce a full-length genome assembly. 

Two reference genome sequences were made publicly available in January 2011, from a ‘Clemenules’ 

clementine-derived haploid and diploid ‘Ridge Pineapple’ sweet orange, produced using Sanger and 454 

sequencing technologies respectively. Subsequent work has proceeded to improve the assemblies and 

their annotation; a brief summary of their characteristics and status of the assemblies will be presented. 

As sequencing technology has evolved and costs have dramatically decreased, other citrus genomes have 

been sequenced (the diploid ‘Clemenules’, ‘Ponkan’, ‘Willowleaf’, ‘W. Murcott’ mandarins; ‘Siamese Sweet’ 

and ‘Chandler’ pummelo; and sour orange, among others). A comparative analysis of these genomes has 

made it possible to describe the genomic contributions from ancestral outbred populations to major 

cultivar types, and to propose likely underlying models. The results confirmed previous reports that 

clementine arose from a hybridization event between ‘Willowleaf’ mandarin and sweet orange. Further, 

introgressions of Citrus reticulata and Citrus maxima germplasm, long implicated in its ancestry, clearly 

defined the segmented mosaic genome of sweet orange, through the ancient admixture of these species. 

Finally, sour orange was found to be a direct hybrid of a pummelo and mandarin. Interestingly, although 

the two pummelos sequenced appear to have their derivations from a single wild species (C. maxima), the 

mandarins sequenced reveal ancestral admixture of C. maxima with C. reticulata. Implications and future 

directions for collaborative research will be discussed. 

S03O02 

Sequencing of 150 citrus varieties: linking genotypes to phenotypes 

Terol J. 1 , Carbonell J. 2 , Alonso R. 2 , Tadeo F.R. 1 , Herrero A. 1 , Ibáñez V. 1 , Muñoz J.V. 1 , López-García A. 1 , Hueso L. 1 , Colmenero-Flores 

J.M. 3 , Conesa A. 2 , Dopazo J. 2 , and Talón M. 1 

1Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Genómica, Spain; 2Centro de Investigación Príncipe Felipe (CIPF), 

Bioinformatics and Genomics Department, Spain; and 3Instituto de Recursos Naturales y Agrobiología (IRNAS), Departamento de 

Biotecnología Vegetal, Spain. talon_man@gva.es 

Elucidation of genomic sequences is an essential and necessary first step to identify genetic variants 

associated with agronomic traits of interest. The CITRUSEQ Consortium, a joint effort developed by public 

institutions and private companies has sequenced the genomes of 150 citrus varieties with the Illumina 

platform at an average coverage higher than 60x. Paired end genomic DNA libraries were constructed and 

average readings of (2x) 100 bp length with an average insert size of 500 bp were performed. For each 

variety, useful total average readings were higher than 220 million and total mapped readings approached 

212 million. The haploid genome of Citrus clementina (www.phytozome.com) was used as a reference 

genome. Sequencing statistics indicate an average representation higher than 92% of the reference genome 

with coverage of 15x. More than 150 citrus genomes including the 3 ancestral taxa and many rootstocks 

and species of mandarins, oranges, lemons, grapefruits and limes were sequenced. The consortium has 

generated a web portal that allows searching and sequence comparison among the approximately 8 

million genes found and the 45 billion base pairs read. Initial analyses suggest that the stored information 

can help unravel fundamental aspects of biological and evolutionary interest such as the origin of citrus, 

the mechanism of generation of spontaneous varieties, the identification of recombination hotspots, the 

effect of induced mutations, etc. Preliminary data suggest, for example, the presence of mitotic crossovers 


S03

S03 

of large genomic regions. Sequence analyses have also shown that natural and induced mutations that 

produce similar changes in the genome also generate similar phenotypes. From the commercial standpoint 

this information may help to authenticate varieties, to support marker-assisted breeding and to identify 

genes of major agronomic interest. 

This work was conducted with funding of projects: PSE-060000-2009-8 and IPT-010000-2010-43 

S03O03 

Whole genome sequencing and mapping analysis for identifying polymorphism among 11 citrus 

varieties 

Shimizu T. 1 , Yoshioka T. 1 , Nagasaki H. 2 , Kaminuma E. 2 , Toyoda A. 2 , Fujiyama A. 2 , and Nakamura Y. 2 

1 NARO Institute of Fruit Tree Science (NIFTS), Citrus Research, Japan; and 2 National Institute of Genetics (NIG), Genome Informatics 

Laboratory, Japan. tshimizu@affrc.go.jp 

NIFTS has been conducting cross-breeding of citrus to develop new promising scions with unique and 

attractive features for consumers. Developing new scions, however, requires 14 to 20 years due to long 

juvenile period of citrus. Marker assisted selection of important traits at the seedling stage is anticipated 

to reduce the total cost of the breeding, and it requires sufficient numbers of genome-wide DNA markers 

to achieve efficient selection. In this study, we sequenced 11 citrus varieties that were widely used in our 

breeding program to obtain sufficient amounts of polymorphic loci among them. Nine of them include 

satsuma, ‘Ponkan’, sweet orange and clementine. Two hybrids were also selected to confirm inheritance 

of called polymorphisms. Next generation sequencing of the citrus varieties was conducted by pairedend 

analysis with HiSeq 2000 DNA sequencer (101 bp for both ends). A total of 100 x genome sequence 

coverage were obtained for each variety, and they were de novo assembled individually. Mapping analysis 

with the clementine haploid sequence as a reference detected more than 100,000 SNPs. Number of SNPs 

and ratios of homozygous SNPs to heterozygous SNPs were different among varieties. Obtained sequences 

for individual varieties with called SNPs would be useful to develop high-throughput genotyping platforms 

and to promote cross-breeding with less cost. 

S03O04 

Sweet orange genome: sequencing, annotation and beyond 

Xu Q. 1 , Ruan X. 2 , Chen L.L. 2 , Chen D.J. 2 , Zhu A.D. 1 , Chen C.L. 1 , Ruan Y. 2 , and Deng X.X. 1 

1 Huazhong Agricultural University (HAU), Horticulture Department, China; and 2 Huazhong Agricultural University (HAU), Colleage of 

Life Science and Technology, China. xuqiang@mail.hzau.edu.cn 

Sweet orange (Citrus sinensis) is one of the most important fruit crops in the world. Orange is responsible 

for approximate 70% of total citrus production, and is used both as fresh fruit and processed juice. Most 

oranges are diploids, with the haploid chromosome number x=9 and estimated genome size of 370 Mb. 

On a double-haploid line of ‘Valencia’ sweet orange, we employed the Illumina/Solexa platform to produce 

785 million high quality paired-end-tag sequencing reads (2×100 bp) from various DNA fragment sizes (~300 

bp, 2 Kb, 10 Kb, and 20 Kb). The sequence reads were assembled by SOAPdenovo and Opera, resulting in 

16,890 assembled sequence contigs and 4,811 scaffolds (N50=1.7 Mb). The total contig sequence length 

covers nearly 90% of the estimated sweet orange genome. We also sequenced more than 5000 BAC-ends, the 

alignments between these BAC sequences and the citrus genome assembly showed an overall high identity. 

To annotate the citrus genome for protein coding genes, a comprehensive strategy that combined ab initio 

gene predictions, homology searches, and experimental supports (EST, RNA-seq and RNA-PET) was employed. 

We generated 965 million RNA-seq reads and 100 million RNA-PET reads from four citrus tissues (callus, leaf, 

flower and fruit) to characterize the orange transcriptomes. In total, 29,655 protein-coding loci (gene models) 

with 44,645 transcripts were identified, with 99% of predicted coding sequences (CDS) supported by RNAseq 

data, demonstrating the high accuracy of gene annotation in the orange genome. The sweet orange 

genome, as a complementary source to the clementine genome released by the International Citrus Genome 

Consortium, represents a valuable resource for genetic understanding of orange biology and manipulation of 

many important traits for citrus breeding. 


S03O05 

A reference genetic map of Citrus clementina; citrus evolution inferences from comparative 

mapping 

Ollitrault P. 1 , Terol J. 2 , Chen C. 3 , Federici C.T. 4 , Lotfy S. 5 , Hippolyte I. 1 , Ollitrault F. 6 , Bérard A. 7 , Chauveau A. 7 , Cuenca 

J. 6 , Costantino G. 8 , Kacar Y. 9 , Mu L. 4 , García-Lor A. 6 , Froelicher Y. 1 , Aleza P. 6 , Boland A. 10 , Billot C. 1 , Navarro L. 6 , Luro F. 8 , 

Roose M.L. 3 , Gmitter Jr. F.G. 3 , Talón M. 2 , and Brunel D. 7 

1Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), BIOS, France; 2Instituto Valenciano de Investigacion Agrarias (IVIA), Genomic Center, Spain; 3Citrus Research and Education Center, University of Florida 

(CREC), USA; 4University of California, Riverside (UCR), Botany and Plant science, USA; 5Institut National de la Recherche Agronomique 

(INRA), Morroco; 6Instituto Valenciano de Investigacion Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; 7Institut National de la Recherche Agronomique (INRA), UR EPGV, France; 8Institut National de la Recherche Agronomique (INRA), UR GEQA, 

France; 9Faculty of Agriculture, University of Çukurova, Department of Horticulture, Turkey; and 10Centre de l’Energie Atomique (CEA), 

DSV/Institut de Génomique, France. patrick.ollitrault@cirad.fr 

The availability of a saturated genetic map of clementine was identified by the ICGC as an essential prerequisite 

to assist the assembly of the reference whole genome sequence based on a ‘Clemenules’ clementine derived 

haploid. The primary goals of the present study were to establish a clementine reference map, and to perform 

comparative mapping with pummelo and sweet orange. Five parental genetic maps were established with 

SNPs, SSRs and InDels. A medium density reference map (961 markers for 1084.1 cM) of clementine was 

established and used by the ICGC to facilitate the chromosome assembly of the haploid genome sequence. 

Comparative mapping with pummelo and sweet orange revealed that the linear order of markers was highly 

conserved. The map should allow reasonable inferences of most citrus genomes by mapping next-generation 

sequencing data against the haploid reference genome sequence. Significant differences in map size were 

observed between species, suggesting variations in the recombination rates. Skewed segregations were 

frequent and higher in the male than female clementine. The mapping data confirmed that clementine arose 

from hybridization between ‘Mediterranean’ mandarin and sweet orange and identified nine recombination 

break points for the sweet orange gamete that contributed to the clementine genome. Moreover it appears 

that the genome of the haploid clementine used to establish the citrus reference genome sequence has been 

inherited primarily from the ‘Mediterranean’ mandarin. 

S03O06 

The chromosomes of citrus: from a unifying nomenclature to the evolution of karyotypes 

Silva S.C. 1 , Mendes S. 1 , Moraes A.P. 1 , Marques A. 1 , Mirkov T.E. 2 , Iglesias D.J. 3 , Ibáñez V. 3 , Talón M. 3 , Soares Filho W.S. 4 , 

Guerra M. 1 , and Pedrosa-Harand A. 1 

1Universidade Federal de Pernambuco (UFPE), Departamento de Botânica, Brazil; 2Texas AgriLife Research (Texas A&M System), 

Department of Plant Pathology and Microbiology, U.S.A.; 3Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Genómica 

y Postcosecha, Spain; and 4Embrapa Cassava&Fruits (EMBRAPA), Brazil. andrea.pedrosaharand@pesquisador.cnpq.br 

Most citrus species have a small genome compartmentalized in nine chromosome pairs (2n=18). Their 

small chromosomes were differentiated in types based on the distribution of heterochromatic blocks when 

the fluorochromes CMA and DAPI were applied. Several cultivars could then be distinguished and hybrids 

identified. Only recently, FISH (fluorescent in situ hybridization) of ribosomal DNA genes (5S and 45S rDNA) 

and BACs (bacterial artificial chromosomes) from Poncirus trifoliata, in combination with the CMA/DAPI 

staining, were used to establish chromosome-specific markers. We have used these markers to identify each 

chromosome pair and build cytogenetic maps of P. trifoliata cv. ‘Flying Dragon’, Citrus reticulata cv. ‘Cravo’, 

Citrus maxima cv. ‘Pink’ and Citrus medica var. ‘Ethrog’. Because the same markers were applied to these 

species, a unifying chromosome nomenclature could be proposed. No breakdown of synteny was detected, 

but most homeologous chromosomes varied in type, indicating differential expansion and contraction of 

heterochromatin. While chromosomes 1, 4 and 8 were conserved, chromosome 3 was especially variable, 

suggesting additional structural rearrangements such as inversions. Those markers were also useful to identify 

the parental chromosomes 2, 3 and 6 in the hybrid Citrus sinensis cv. ‘Valencia’, corroborating C. maxima and 

C. reticulata as its putative ancestors. The present addition of anchored mandarin BACs to the cytogenetic 

map will integrate it to the citrus genome sequence. 

Financial support: CNPq, FACEPE and CAPES, Brazil 


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S03O07 

Analysis of the clementine floral transcriptome uncovers candidate genes involved in selfincompatibility 

Caruso M. 1 , Lo Cicero L. 1 , Distefano G. 1 , Merelo P. 2 , La Malfa S. 1 , Tadeo F.R: 2 , Talón M. 2 , Lo Piero A.R. 1 , and Gentile A. 1 

1 University of Catania (DISPA), Department of Agriculture and Food Science, Italy; and 2 Instituto Valenciano de Investigaciones 

Agrarias (IVIA), Centro de Genómica, Spain. gentilea@unict.it 

Self-incompatibility (SI), typical of many mandarin and pummelo varieties, is a valuable trait to obtain seedless 

fruits. Despite the importance of SI, the genetic basis of this trait in citrus is poorly understood. Two clementine 

genotypes showing divergent behaviour related to self-pollen rejection (‘Comune’, self-incompatible’; and 

‘Monreal’, self-compatible) were chosen as model to study the molecular events occurring during pollen-pistil 

interaction and the self-incompatible response. The comparative analysis of the floral transcriptome of the two 

clementine genotypes led to identifying a set of candidate genes related to SI. The identified genes show no 

homology to SI genes of other plant species and lack annotation. Functional analyses are therefore needed to 

unravel their function and to confirm their role in the citrus progamic phase. Our attention focused on 4 genes 

over- represented in the’ Comune’ transcriptome whose expression drastically increased in concomitance with 

the halting of pollen tube elongation, namely a putative F-box protein gene and three aspartic-acid rich (Asprich) 

protein encoding genes. A first step of the functional characterization consisted in their over-expression 

in tobacco plants. Moreover, the Asp-rich proteins were expressed in a cell-free system and purified for a 

biochemical characterization. The preliminary results of the functional analyses are discussed. 

S03O08 

Citrus gene function analysis using a viral vector based on the Citrus leaf blotch virus genome 

Agüero J., Velázquez K., Vives M.C., Pina J.A., Navarro L., Moreno P., and Guerri J. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Mocada, Valencia, Spain. 

jaguero@ivia.es 

Genetic improvement of citrus by conventional breeding is hindered by their complex reproductive biology, high 

heterozygosis and long juvenile period (up to 6-8 years). Moreover, the genes responsible for each biological 

process are presently unknown. Since viral vectors allow rapid testing of gene function, they may be a better 

tool than transgenic expression for improvement of citrus, whose adult plants are difficult to transform. We 

have developed vectors based on the Citrus leaf blotch virus (CLBV) genome by i) introducing in a full-genome 

infectious cDNA clone a unique restriction site in the 3’ untranslated region (clbv3´ vectors) or at the intergenic 

region between the movement protein and the coat protein (CP) genes (clbvIN vectors), and ii) duplicating 

in these positions a minimum promoter derived from the natural promoter sequence of the CP subgenomic 

RNA. When fragments of the phytoene desaturase, magnesium chelatase or actin genes were cloned in those 

vectors and then inoculated onto different citrus species all plants showed the silencing phenotype and reduced 

accumulation of the cognate mRNAs. This phenotype was observed in successive flushes for at least 2 years 

and the inserts remained stable as tested by RT-PCR with primers flanking the insertion site. Expression of the 

FLOWERING LOCUS T in young seedlings using those vectors incited flowering in just 4 months. This dramatic 

reduction of the juvenile period may be a useful tool for citrus genetic improvement. 

S03P01 

Expression analysis of genes differentially expressed in stem tissue of two lemon cultivars. 

Koutsioumari E.M., and Voloudakis A.E. 

Agricultural University of Athens (AUA), Laboratory of Plant Breeding and Biometry, Department of Crop Science, Greece. 

eva.kouts@yahoo.gr 

Lemon (Citrus limon) cultivation in Greece and other Mediterranean countries suffers from two major problems: 

the destructive disease Mal Secco caused by the fungus Phoma tracheiphila and chilling injury caused by low 

temperatures. The knowledge of genes involved in resistance to the above mentioned stresses would be useful 

in breeding tolerant lemon cultivars. In order to determine the molecular basis of resistance to these stresses, 


suppression subtractive hybridization (SSH) was applied on two lemon cultivars exhibiting differences in 

resistance to Mal Secco and cold, namely ‘Lisbon’ (susceptible to both stresses) and ‘Adamopoulou’ (tolerant 

Greek cultivar), which is believed to have derived from ‘Lisbon’. Two subtractions were performed resulting 

in two subtractive cDNA libraries: ‘Adamopoulou-Lisbon’ containing sequences expressed preferentially in 

‘Adamopoulou” and ‘Lisbon-Adamopoulou’ containing genes expressed in ‘Lisbon’. A total of 587 clones 

were sequenced and the obtained sequences were edited resulting in 81 non-redundant ESTs that have been 

deposited in GenBank EST database. The analysis of these sequences using BLAST software (NCBI) revealed 

homology to previously identified genes involved in defense mechanisms against biotic and abiotic stresses. 

ESTs from each subtractive library were selected for further analysis of their expression in both cultivars by 

performing semi-quantitative RT-PCR reactions. The results of this experiment will be discussed. 

S03P02 

Transcriptome profile analysis of Citrus Canker resistance of Chinese citron (Citrus medica) via 

massively parallel mRNA sequencing 

Li D.Z. 1 , Dai S.M. 2 , Li N. 2 , and Deng Z.N. 2 

1 Provincial Key Laboratory of Crop Germplasm Innovation and Utilization (PKLCGIU), Hunan Agricultural University, China; and 

2 National Center for Citrus Improvement, (NCCI), Hunan Agricultural University, China. ldazhi@163.com 

Citrus Canker (Xanthomonas axonopodis pv. citri) has brought great damage to citrus industry worldwide. To 

control the disease, it seems the use of resistant genotypes is the only choice. A total of 14 accessions from 

three species were investigated by artificial inoculation on leaves with the pathogen, and it was found that 

only Chinese citron (Citrus medica) showed complete and active resistance to canker disease. Comparative 

transcript profiling of leaves after inoculating pathogen on resistant Chinese citron by using massively parallel 

signature sequencing (MPSS) was performed. Samples from 3 stages (RC1,RC2,RC3) according to the symptom 

development were chosen and they were divided into the susceptible stage (SS) and the resistant stage (RS). A total 

of 13,396,168,12,747,212 and 13,491,020 high quality clean reads were obtained for the samples, respectively. 

Interpretation of the MPSS signatures revealed that the total number of transcribed genes in the SS (18,045) was 

larger than that in the RS (17,394). Further comparison of the transcripts revealed that 2554 genes had nearly 

twofold expression difference in the RS compared with the SS (1409). Especially, the number of down-regulated 

genes in the RS (1984) is much higher than that in the SS (470), suggesting that many genes were restrained in the 

RS. In addition, we identified more than 20 genes that were involved in the plant-pathogen interaction pathway. 

These genes are highly conserved in citrus and other species, suggesting that the function of the related proteins 

in resistance to bacterial disease may be conserved as well. Our results provide a foundation for comparative 

gene expression studies about the incursive development of that citron was inoculated by pathogen. Additionally, 

a number of candidate genes that were involved in resistance to disease were identified. These results provide 

new insight into the molecular processes regulating resistance to Citrus Canker. 

S03P03 

Characterization of genes associated with two agronomically important traits in citrus: drought 

tolerance and fruit color 

Costa M.G.C. 1 , Cidade L.C. 1 , de Oliveira T.M. 1 , Martins C.P.S. 1 , Mendes A.F.S. 1 , Pereira S.L.S. 1 , Pedrosa A.M. 1 , Gesteira 

A.S. 2 , Girardi E.A. 2 , Coelho-Filho M.A. 2 , Soares Filho W.S. 2 , and Machado M.A. 3 

1State University of Santa Cruz (UESC), Center for Biotechnology and Genetics, Brazil; 2Embrapa Cassava & Fruits (EMBRAPA-CNPMF), 

Brazil; and 3Instituto Agronômico de Campinas, Centro APTA Citros Sylvio Moreira, Brazil. marciogc.costa@gmail.com 

Drought tolerance and fruit color are important traits to citrus producers and consumers. Because citrus 

cultivation is mainly located in regions subjected to long periods of water shortage, drought is one of the 

main factors affecting citrus productivity worldwide. On the other hand, the color of citrus fruits provided 

by carotenoid pigments is one of the most important attributes of fruit quality and consumer acceptance. 

Within the scope of the National Science and Technology Institute of Genomics for Citrus Breeding, with 

support of Embrapa Cassava & Fruits, our group has focused on functional characterization of genes affecting 

drought tolerance and fruit color in citrus. To this end, we are using the tools of genomics, molecular biology, 


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and recombinant DNA technology. Some of the results already obtained include: (1) identification of novel 

members of the NAC, WRKY and NF-Y transcription factor gene families involved in drought stress response, 

(2) characterization of LEAs and a TIP2;1-like aquaporin conferring tolerance to dehydration, (3) description 

of an alternative mechanism of ABA biosynthesis regulation and abiotic stress tolerance provided by the 

phytoene synthase gene, (4) characterization of two novel lycopene beta-cyclase genes controlling betacarotene 

biosynthesis in photosynthetic- or chromoplast-containing tissues, and (5) identification of several 

alternatively spliced isoforms of the lycopene epsilon-cyclase gene. 

Financial support: CNPq, FAPESP, Embrapa, CAPES, FAPESB 

S03P04 

Expression of Ptcor8 gene induced by low temperature as related to cold resistance in citrus 

Long G.Y. 1 , Song J.Y. 1 , Luo K. 1 , Deng Z.N. 2 , Li N. 2 , and Gentile A. 1 

1 College of Horticulture and Landscape (CHL), Hunan Agricultural University, China; and 2 National Center for Citrus Improvement- 

Changsha Subcenter (NCCICS), Hunan Agricultural University, China. longgy63@163.com 

Ptcor8 (EU077497) gene was previously isolated from the leaf of trifoliate orange (Poncirus trifoliata) 

naturally cold acclimated in field. In different investigations it was found that the expression of Ptcor8 gene 

may not be directly related to the physiological defoliation of trifoliate orange, but rather closely related to 

low temperature induction. In the whole cold acclimation process in different citrus genotypes, when the 

temperature decreased to or below 5 o C, the expression of the gene significantly increased. The maximum 

expression level was observed in the most cold-tolerant trifoliate orange, followed by kumquat (Fortunella 

crassifolia), pummelo (Citrus grandis), sweet orange (Citrus sinensis), and the minimum in lemon (Citrus 

limon), indicating that Ptcor8 expression was relatively closed to low temperature and related to cold 

tolerance of different citrus species. Then, the genomic DNA sequences of Ptcor8 from Poncirus and lemon 

were cloned and analyzed. Results showed that the two homologous genes contain four exons and three 

introns, and shared high identity of 98.31% and 96.12% in nucleotide and amino acid sequence, respectively. 

So, we further cloned the promoter sequences from Poncirus and lemon. The size of consensus sequence 

from lemon was 2053bp. Promoter sequences from trifoliate orange are divided into two types and the 

sizes were 1973bp and 1991bp, respectively. Predication of cis-acting elements in promoter sequences 

demonstrated that no difference of cis-acting elements-is there-in two types of promoter sequences from 

trifoliate orange. There is low-temperature responsive cis-acting element (LTRE) in the promoter sequences 

of lemon and trifoliate orange, but some elements related to stress responsiveness only exist in promoter of 

trifoliate orange, whereas auxin-responsive element only in promoter of lemon. 

S03P05 

Cloning and characterization of a prolin-rich protein gene CsPRP4 from citrus 

Ma Y.Y. 1 , Zhang L.Y. 2 , Zhu S.P. 3 , and Zhong G.Y. 4 

1 Key Laboratory of Horticulture for Southern Mountain Regions, Ministry of Education, China; 2 Guizhou Normal University, Guiyang, 

China; 3 Citrus Research Institute, Southwest University, China; and 4 Key laboratory of South Subtropical Fruit Biology and Genetic 

Resources, Ministry of Agriculture, China. zhongyun99cn@163.com 

Proline-rich proteins (PRPS) represent a class of cell wall proteins that possess repetitive proline and 

hydroproline residues. In this study, we isolated a novel PRP gene that was designated as CsPRP4 from citrus. 

Expression analysis showed that the CsPRP4 transcript was existed preferentially in leaves and significantly 

up-regulated by exogenous ethylene treatment. A 1.5kb promoter sequence of CsPRP4 gene was cloned 

from Citrus sinensis genome and its activity was assayed by using a GUS reporter gene under its control. 

The promoter is shown to direct the expression of the GUS gene in leaves and cotyledons of the transgenic 

Arabidopsis thaliana. To study the function of CsPRP4, we transformed citrus with a binary vector containing 

a full length clone of CsPRP4 in sense orientation and also a vector containing an RNAi construct to study the 

function of the gene. The RNAi plants exhibited a stunted phenotype by showing leaves significantly smaller 

than both the over-expression plants and the wild type plants. Electron microscopy revealed that blocking 

the expression of CsPRP4 in the RNAi plants reduced the number and size of starch grains in chloroplasts, 

indicating that CsPRP4 may be involved in development and carbohydrate metabolism of leaves. 


S03P06 

Ploidy and gene expression in clementine 

Niñoles R., Aleza P., Castillo M.C., Navarro L., and Ancillo G. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain. ancillo@ivia.es 

Polyploidy has long been recognized as an important force in the evolution of flowering plants as often results 

in novel phenotypes that are not present in their diploid progenitors or exceed the range of the contributing 

species. The new acquired phenotypes may have an advantage in adaptation that may also enhance their 

interest for agriculture. Many crops, including citrus, are bred to a higher level of ploidy in search of desirable 

traits. In previous works of our group, synthetic clementines with different levels of ploidy were generated, 

specifically haploid, dihaploid and autotetraploid lines were obtained. This plant material represents a valuable 

tool for studying the effects of polyploidization at a molecular level since important traits are expressed in 

a different manner. Interestingly, dihaploid lines have been not able to flower, while haploid, diploid and 

autotetraploid lines have. By using a microarray approach, we have accomplished a comprehensive analysis 

of transcriptome divergence among the newly created clementine lineages with different genome dosage 

and specifically have explored new gene expression patterns related to the ability to flower. Differences in 

expression in the bark tissue of the four lineages were found significant for ninety four genes. Clustering 

analysis results and expression profile of these genes in the 4 compared lineages were used as additional 

criteria to select 16 genes putatively involved in the flowering differences found in the lineages. To explore 

their potential involvement in the flowering event we have analyzed their expression in floral organs and 

the occurrence of differential expression in juvenile and adult bark tissues. Results and discussion will be 

presented. 

S03P07 

Expression of flowering genes in different shoot types in citrus 

Muñoz-Fambuena N. 1 , Mesejo C. 1 , González-Mas M.C. 2 , Iglesias D.J. 2 , Primo-Millo E. 2 , and Agustí M. 1 

1 Universitat Politècnica de València (UPV), Instituto Agroforestal Mediterráneo, Spain; and 2 Instituto Valenciano de Investigaciones 

Agrarias (IVIA), Centro de Citricultura y Producción Vegetal, Spain. namuofam@upvnet.upv.es 

In citrus, three main shoot types can be distinguished: vegetative shoots (VS), leafy inflorescences (LY) 

and leafless inflorescences (LS). This study aimed to determine the relationship between flowering genes 

expression and shoot type. To this end, shoots of ‘Moncada’ mandarin were collected at the beginning of 

bud sprouting, and-flowering genes expression was analysed by RT-PCR. LS and LY did not-significantly differ 

in the number of flowers per inflorescence. However, they significantly differed in flowering genes relativeexpression. 

Thus, LS presented the highest relative expression of the-flowering genes CiFT, CsAP1, CsLFY, 

CiSEP1 and CiSEP3, and the lowest of that flowering inhibitor CsTFL, whereas VS showed the opposite. LY 

showed intermediate relative expression between VS and LS of either flowering promoters or inhibitor. 

Results indicate an absence of relationship between the number of flowers per inflorescence and relative 

gene expression. On the other hand, the different levels of expression of flowering genes, CiFT, floweringtime, 

CsTFL, CsLFY, CsAP1, meristem identity and CiSEP1 and CiSEP3, floral organ specification, seem to be 

related with the-appearance of different shoot types. 

S03P08 

Shortening the juvenile phase in Arabidopsis plants by ectopic expression of citrus transcription 

factors 

Castillo M.C., Navarro L., and Ancillo G. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain. ancillo@ivia.es 

In citrus, juvenility is a long period (5-20 years depending on the variety) during which floral initiation does not 

occur even under normally inductive environmental conditions. Efficient breeding is limited due to this long 

period of juvenility. Several transcription factors (TFs) were identified as differentially expressed in juvenile 

and adult phases in an approach involving the use of a microarray containing 1152 putative unigenes of citrus 


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TFs. Some of them are MADS-box genes, a family of TFs involved in developmental processes whereas others 

showed high partial sequence similarity restricted to specific domains but negligible outside those domains. 

Transgenic Arabidopsis plants overexpressing these TFs were generated and number of leaves without abaxial 

trichomes, flowering time and morphology of leaves, siliques and whole plants have been analysed. Transgenic 

lines for four of the TFs showed shortening of the juvenile phase, indicating that these genes are likely 

involved in determining the reproductive phase transition also in citrus. Lines which showed no phenotype 

differences corresponded to TFs that have not yet been characterized in other plants and therefore they 

might be novel genes that play specific roles during the juvenile-to-adult transition in citrus. This makes them 

good candidates to study the specific aspects of juvenility in citrus. Deciphering the molecular mechanisms 

involved in the juvenile-to-adult transition in citrus plants is crucial if we expect to reduce the generation time 

for genetic studies and breeding programs. Our results represent a step forward in the knowledge of these 

processes in citrus and offer the prospect of rapid transfer of information to other woody plants. 

S03P09 

Differential expression of proteins related to primary metabolism in ‘Moncada’ mandarin leaves 

with contrasting fruit load 

Muñoz-Fambuena N. 1 , Mesejo C. 1 , Agustí M. 1 , Tárraga S. 2 , Iglesias D.J. 3 , Primo-Millo E. 3 , and González-Mas M.C. 3 

1 Universidad Politécnica de Valencia (UPV), Instituto Agroforestal del Mediterráneo, Spain; 2 Universidad Politécnica de Valencia 

(UPV), Instituto de Biología Molecular y Celular de Plantas, Spain; 3 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de 

Citricultura y Producción Vegetal, Spain. gonzalez_mde@gva.es 

A proteomic study was used to know how the primary metabolism in citrus leaves is affected by the fruit 

load. To this end, we researched the differential expression of proteins related to these processes between 

on-crop and off-crop ‘Moncada’ mandarin leaves. Samples were collected in November and proteins were 

extracted. From 2D DIGE gel of these extracts, 33 spots related to primary metabolism were isolated: 26 spots 

being associated with photosynthesis and carbohydrate metabolism, 4 spots related to Krebs cycle, 1 spot 

related to pentose phosphate pathway, and 2 spots related to nutrient reservoir activity. These spots were 

identified by MALDI-MS or LC-MS-MS. Between the proteins related to photosynthesis and carbohydrate 

metabolism, 16 were up-expressed in off-crop leaves, such as Nadp-dependent glyceraldehyde-3-phosphate 

dehydrogenase, RuBisCO large subunit, ADP-glucose pyrophosphorylase, cinnamoyl-CoA reductase, and 

carbonic anhydrase; while 10 proteins were up-expressed in on-crop leaves such as NADP-dependent malic 

enzyme, and 3,4-dihydroxy-2-butanone kinase. The isolated proteins related to pentose phosphate pathway 

(6-phosphogluconate dehydrogenase) and to nutrient reservoir activity (Granule-bound starch synthase Ib 

precursor) were up-expressed in off-crop leaves. Regarding the proteins related to Krebs cycle, only malate 

dehydrogenase was up-expressed in off-crop leaves, while the other proteins were up-expressed in on-crop 

leaves (citrate synthase and NADP-isocitrate dehydrogenase). According these results, the primary metabolism 

seems to be more active in off-crop leaves, suggesting that fruit load inhibits the primary metabolism in 

‘Moncada’ mandarin. This work has been supported by the Project INIA RTA2009-00147-C02 and Fundación 

Agro Alimed. 

S03P10 

Proteins related to stress and redox state of Moncada mandarin leaves with contrasting fruit load 

Muñoz-Fambuena N. 1 , Mesejo C. 1 , Agustí M. 1 , Tárraga S. 2 , Iglesias D.J. 3 , Primo-Millo E. 3 , and González-Mas M.C. 3 

1 Universidad Politécnica de Valencia (UPV), Instituto Agroforestal del Mediterráneo, Spain; 2 Universidad Politécnica de Valencia 

(UPV), Instituto de Biología Molecular y Celular de Plantas, Spain; 3 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de 

Citricultura y Producción Vegetal, Spain. gonzalez_mde@gva.es 

A proteomic study was used to know more about the citrus redox state and response stress related to fruit 

load. To this end, we researched expression differences of proteins related to these processes between oncrop 

and off-crop ‘Moncada’ mandarin leaves. Samples were collected in November, were immediately stored 

frozen at -80 ºC, and proteins were extracted in less than two weeks. From 2D DIGE gel of these extracts, 12 

related spots were isolated: only 1 showed increased expression in the off-crop samples compared to on-crop 


samples, while the other 11 showed increased expression in the on-crop samples against off-crop samples. 

These spots were identified by MALDI-MS or LC-MS-MS. The only protein with increased expression in the offcrop 

samples was putative monocopper oxidase precursor, while the up-expressed proteins in on-crop leaves 

were catalase, monodehydroascorbate reductase, Fe-superoxide dismutase, glutathione peroxidase, and 

three proteins related to response stress. Thus according to these results, generally, in the off-crop samples, 

proteins with oxidoreductase activity are down-regulated, while in the on-crop samples the proteins related 

to stress response and to oxidoreductase activity are up-regulated. Therefore, the redox state is different for 

off-crop and for on-crop Citrus leaves. 

This work has been supported by the Project INIA RTA2009-00147-C02 and Fundación AgroAlimed. 

S03P11 

Genomic compositions and origins of Citrus sinensis, Citrus clementina and Citrus poonensis as 

revealed by genome-wide analysis of citrus ESTs 

Zhong G.Y. 1 , Wu B. 2 , Zeng J.W. 1 , Jiang B. 1 , and Yang R.T. 2 

1 Institute of Fruit Tree Research, Guangdong Academy of Agricultural Science, China; and 2 Citrus Research Institute, Southwest University, 

China. zhongyun99cn@163.com 

The origins of Citrus sinensis, Citrus clementina and Citrus poonensis are largely unknown. A genome-wide 

analysis of citrus EST sequences was performed in this study to address this issue. A considerably high level 

of SNP polymorphisms in citrus was found by analyzing ESTs. The interference from the allelic expression 

bias associated with EST analysis was eliminated by using only the unigenes with enough sequence coverage. 

Two approaches, haplotype comparison and phylogenetic analysis were used to analyze the 359 different 

gene loci of citrus. It was shown that all the three species, C. sinensis, C. clementina and C. poonensis are 

genome-wide heterozygous. Inference from analyzing EST data was that C. clementina was derived from 

a cross between a mandarin and C. sinensis, and the mandarin was confirmed to be Citrus deliciosa by 

genotyping 25 representative SNPs. Statistically C. sinensis must be originated from three consecutive 

crosses, i.e., [(pummelo × mandarin) × pummelo or pummelo × (pummelo × mandarin)] × mandarin, and 

the supposed immediate mandarin parent was experimentally searched but not found. The evolution and 

domestication of citrus and the significance of high level of SNP polymorphisms were discussed. Information 

from ESTs provided some clues to the elucidation of the heterosis mechanism leading to the superiority of 

the three most important and widely cultivated citrus. EST based analysis and SNP genotyping are valuable in 

inferring the origins of cultivated Citrus species. The origins of C. sinensis, and C. clementina were revealed. 

The genome of C. poonensis was analyzed. 

S03P12 

Genomic sequencing and comparative analysis of Citrus platymamma (Byungkyool) by using 

next-generation sequencing technology 

Chung S.J. 1 , Han S.I. 2 , Jin S.B. 3 , Kim Y.W. 1 , Yun S.H. 4 , Riu K.Z. 2 , and Kim J.H. 2 

1 Research Institute for Subtropical Horticulture, Jeju National University, Korea; 2 Faculty of Biotechnology, College of Applied Life 

Science, Jeju National University, Korea; 3 Subtropical & Tropical Organism Gene Bank, Jeju National University, Korea; and 4 Citrus 

Research Station, National Institute of Horticultural & Herbal Science, Rural Development Administration, Korea. kimjh@jejunu.ac.kr 

Next-generation sequencing (NGS) technologies are being utilized for de novo sequencing, genome resequencing, 

and whole genome and transcriptome analysis. Citrus platymamma (Byungkyool) has been known 

to be a native citrus species in Jeju Island, South Korea. In this study, we have sequenced C. platymamma 

genome to analyze genome structure and gene function. Genomic DNA was obtained from leaves of C. 

platymamma and about 25 Gb short-read sequences produced by the Illumina paired-end sequencing 

technology. The initial assembly was contained 321 Mbp of C. platymamma genome in 20,818 scaffolds with 

N50 size of 60Kbp. These scaffolds contained 176,765 contigs in which N50 size was 3.5 Kbp. Comparison 

with the sweet orange sequence, a total of 40,905 genes of C. platymamma were confirmed. This genome 

sequence data will be used to characterize potential roles of new genes in Byungkyool and can be used in 

comparative studies of other Citrus species. 


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S03P13 

Fast and cost-effective DNA marker typing method with accuracy for citrus by direct PCR and 

multiplexed post-labeling 

Ohta S. 1 , Yano K. 1 , Kurita Y. 2 , Kita M. 1 , Yoshioka T. 1 , Nesumi H. 1 , and Shimizu T. 1 

1 NARO Institute of Fruit Tree Scie (NIFTS), Okitsu Citrus Research Station, Japan; and 2 Aichi Agricultural Research Center (Aichi Pref), 

Department of Horticultural Research, Japan. sohta@affrc.go.jp 

DNA marker typing has been used in citrus for many purposes such as linkage mapping, marker-assisted 

selection, and cultivar identification. However, DNA marker typing is time-consuming and costly in citrus 

because of requiring highly purified DNA to eliminate compounds that strongly inhibit PCR. Fragment 

analysis with capillary DNA sequencer enables highly accurate genotyping analysis but it requires expensive 

fluorescently labeled primers that are another cost factor. We developed direct PCR method for citrus in 

order to achieve fast and cost-effective genotyping. This method consists of two steps; (1) pricking a leaf 

sample with a toothpick, and (2) dipping the toothpick into a PCR mixture or a TE buffer solution directly 

to prepare a DNA sample. The prepared DNA sample was then provided for PCR analysis. We were able to 

process 95 samples within 1.5 h, in contrast to 23 h by conventional DNA extraction method. Subsequent 

PCR amplification using five different STS markers was highly successful (96–100%) except for the 1200 bp 

marker using the DNA samples dissolved in TE buffer solution (86%). We combined the direct PCR method 

with multiplexed post-labeling method for fragment analysis with DNA sequencer, which enables multiplexed 

post-labeling of DNA markers (up to 6) in a single tube without laborious labeling step. As a consequence, 

total cost was decreased to one tenth or less than those using pre-labeled primers. 

S03P14 

Data mining and systems biology for identifying key genes involved in citrus quality 

Silva E.M.A. 1 , Bernardes L.A.S. 1 , Ollitrault P. 2 , Bonatto D. 3 , and Micheli F. 1 

1 Universidade Estadual de Santa Cruz (UESC), DCB, Brazil; 2 Centre de Cooperation Internationale en Recherche Agronomique pour le 

Developpement (CIRAD), BIOS - UMR AGAP, France; and 3 Universidade Federal do Rio Grande do Sul (UFRGS), DBMB, Brazil. 

fabienne.micheli@cirad.fr 

Quality in citrus is mainly characterized by fruit and juice colour, fruit and skin size, juice percent, total 

soluble solids, titrable acidity, and carotenoid/flavonoid contents. Moreover, studies of biosynthetic pathway 

of the metabolites/proteins involved in quality at transcriptional and translational levels may give relevant 

information for subsequent functional studies and quality improvement. Data mining of ESTs from HarvEST 

database allowed the selection of 17 cDNA libraries from albedo, flavedo, peel, pulp and juice sac of different 

orange, mandarin, clementine and grapefruit varieties. In order to select key genes involved in quality we 

used systems biology that offers mathematical tools that include the analysis of the structure, clustering 

and centralities of the network. In order to have information regarding physical protein-protein interactions 

(PPPI) from citrus sequences, orthologous sequences of Arabidopsis thaliana were used (BLASTX; reciprocal 

BLASTP). Literature data mining was performed, and PPPI network design was obtained using the Cytoscape 

software. The interactome networks thus obtained were analyzed with MCODE. Gene ontology clustering 

analysis was performed using BiNGO. Specific algorithms were applied to identify modules and central nodes 

within the citrus libraries associated network. The obtained results will be used as a guideline to select specific 

genes/proteins from citrus for further functional studies as gene expression or plant transformation. 

S03P15 

Genotyping and mutation scanning by high resolution melting (HRM) analysis of citrus EST-SNPs 

and SSRs 

Distefano G. 1 , La Malfa S. 1 , Caruso M. 1 , Lo Piero A.R. 1 , Nicolosi E. 1 , and Shu-Biao W. 2 

1 Università degli Studi di Catania (DISPA), Dipartimento di Scienze delle Produzioni Agrarie e Alimentari, Italy; and 2 University of New 

England, School of Environmental and Rural Science, Armidale, Australia. slamalfa@unict.it 

Citrus taxonomy is very complex mainly due to specific aspects of its reproductive biology. A number of studies 

have been performed using various molecular markers in order to evaluate the level of genetic variability 


in citrus. SNP markers were used for genetic diversity assessment using different methods; recently, the 

availability of EST database and whole genome sequences increased the information on sequence variability 

in citrus leading to wider employment of these markers so that reliable SNP detection methods are needed. 

In the present study, for the first time we applied high resolution melting curve analysis (HRM) in citrus 

to detect the presence of SNPs or SSRs polymorphisms. In citrus, the possibility of characterizing genetic 

diversity was drastically increased using this method since it allowed analyzing more polymorphisms in a 

single PCR fragment. The results suggest that HRM is an efficient, cost-effective and accurate method to 

detect sequence variations. In fact, HRM analysis provided a panel of primers for HRM genotyping in citrus 

representing also a useful tool for bridging functional and structural genomics. 


S03

Session 05 

BIOTECHNOLOGY 

S05

S05O01 

Unlocking the molecular secret of blood orange 

Butelli E. 1 , Licciardello C. 2 , Reforgiato-Recupero G. 2 , and Martin C. 1 

1 John Innes Centre (JIC), Metabolic Biology, UK; and 2 Centro di Ricerca per l’Agrumicoltura e le Colture Mediterranee (CRA), Italy. 

eugenio.butelli@jic.ac.uk 

The derivation of blood orange has been an outstanding question in horticulture for several centuries and 

consumer interest in this variety has risen significantly in recent years with the demonstration that consumption 

of blood orange juice promotes health and prevents obesity. We have investigated the molecular basis for the 

blood orange trait and shown that all Mediterranean blood oranges are derived from the insertion of a copialike 

retrotransposon in a gene (Ruby) encoding a transcription factor that regulates anthocyanin biosynthesis. 

We show that Ruby has come under the control of the retrotransposon LTR that provides a core promoter 

for Ruby expression. The cold-dependency of fruit pigmentation reflects the induction of expression of the 

retroelement by this abiotic stress. Amongst blood orange accessions in China, we have discovered a different 

molecular event; it was caused by a related retrotransposon that promotes anthocyanin biosynthesis through 

a parallel but distinct mechanism. Analysis of the Ruby locus in citrus indicated that many species and hybrids 

are unable to accumulate anthocyanins because they lack a functional copy of the Ruby gene while, in other 

citrus plants, anthocyanin pigmentation is dependent on the association between Ruby and retrotransposons. 

Our analysis provides a model for the evolution of the anthocyanin trait in Citrus and suggests that transposable 

elements may be responsible for generating much of the diversity available in this genus. 

S05O02 

A novel carotenoid cleavage activity responsible for the biosynthesis of citrus fruit-specific 

apocarotenoids 

Rodrigo M.J. 1 , Alquézar B. 2 , Carmona L. 1 , Alós E. 1 , Al-Babili S. 3 , and Zacarías L. 1 

1 Instituto de Agroquímica y Tecnología de Alimentos-CSIC (IATA), Departamento de Ciencia de los Alimentos, Spain; 2 Instituto 

Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; and 3 University of Freiburg, Faculty 

of Biology, Germany. mjrodrigo@iata.csic.es 

The C30 apocarotenoids, β-citraurin and 8-β-apocarotenal, are specific of the genus Citrus and accumulate in 

the peel of oranges and mandarins, providing an attractive orange-reddish coloration. However, the genes/ 

enzymes involved in the biosynthesis of these compounds are currently unknown. The oxidative cleavage 

of carotenoids to produce apocarotenoids is catalyzed by a family of enzymes referred to as carotenoid 

cleavage dioxygenases (CCD). In this work, we report the identification of a novel CCD gene in citrus, named 

as CsCCD, whose expression was restricted to chromoplastic tissues and specifically to the fruit peel. CsCCD 

was induced during fruit maturation and stimulated by different postharvest treatments that enhanced fruit 

peel coloration, and, in good correlation with accumulation of C30 apocarotenoids. In order to determine 

the potential cleavage activity, CsCCD was coexpressed into E. coli strains accumulating different carotenoids 

and the production of apocarotenoids were analyzed by HPLC-PDA-MS and HS-SPME-GC-MS. Interestingly, 

only the strains accumulating β-carotene or zeaxanthin were able to produce the expected C30 and C10 

apocarotenoids. Collectively, these results suggest that CsCCD may be an enzyme responsible for the 

biosynthesis of the Citrus-specific C30 apocarotenoids, and its involvement in fruit coloration, as well as the 

potential in vivo substrates will be discussed. 

S05O03 

Biosynthesis and regulation of carotenoids in citrus callus 

Xu J., Gao H.J., Deng X.X., and Zhang H.Y. 

Key Laboratory of Horticultural Plant Biology, Ministry of Education, (HZAU), College of Horticulture and Forestry, China. 

xujuan@mail.hzau.edu.cn 

Carotenoid profiles in citrus callus varied with genotypes and sub-cultures, while were stable within a genotype. 

Though their composition is different in fruit tissues and leaves, citrus callus is effective material in understanding 


S05

S05 

the regulation of carotenogenesis, due to its theoretically identical genetic background to other plant tissues. Light 

regulates the carotenoids synthesis. White light hampered the carotenoids biosynthesis in callus of ‘Red Marsh’ 

grapefruit (Citrus paradisi), while boosted it in ‘Tarocco’ blood orange (C. sinensis); the synthesis of carotenes 

seemed more sensitive to light than xanthophylls; PSY transcription was up-regulated in callus of two sweet 

oranges, while was down-regulated in ‘Murcott’ tangor (C. reticulata × C. sinensis); PSY was emphasized as a ratelimiting 

gene; however, in the callus of ‘Red Marsh’, PDS and ZDS might be the rate-limiting genes with an inhibited 

transcription. Sucrose supply affects carotenoids production. Sucrose starvation induced decreased carotenoid 

production in callus of ‘Red Marsh’. Microarray analysis declared more than 1600 up- and down-regulated genes 

with 4-fold change. Among them, the expression of most carotenogenesis genes was boosted. Interestingly, the 

expression of transcription factors, such as AP2, was largely altered. The network began with sucrose starvation 

to the carotenoid decrease; the senescence signalling and the regulation of transcription factors will be discussed. 

S05O04 

Terpene downregulation triggers innate immunity and resistance to fungal pathogens in orange 

fruits 

Rodríguez A. 1 , Shimada T. 2 , Cervera M. 1 , Alquézar B. 1 , Gadea J. 3 , Gómez-Cadenas A. 4 , de Ollas C. 4 , Rodrigo M.J. 5 , Zacarías 

L. 5 , and Peña L. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; 2 National Institute of 

Fruit Tree Science. National Agricultural Research Organization, Okitsu Citrus Research Station, Japan; 3 Instituto de Biología Molecular 

y Celular de Plantas. CSIC-Universidad Politécnica de Valencia. (IBMCP), Spain; 4 Escuela Superior Ciencias Experimentales y Tecnología. 

Universidad Jaume I de Castellón, Departamento de Ciencias Agrarias y del Medio Natural, Spain; and 5 Instituto de Agroquímica y 

Tecnología de Alimentos-CSIC (IATA), Departamento de Ciencia de los Alimentos, Spain. arodrig@ivia.es 

Volatile organic compounds, most of them being terpenes, are signals emitted by plants for communication 

with the environment. Orange fruit accumulates mainly terpenes in mature peel oil glands, D-limonene 

accounting for approximately 97% of terpene content. We have generated transgenic orange plants carrying a 

D-limonene synthase gene in antisense (AS) configuration. Transgenic expression caused a dramatic decrease 

in the accumulation of D-limonene in fruit peels, being about 80-100 times lower in AS samples than in empty 

vector (EV) transgenic ones. This affected the interaction of fruits with their biotic environment because 

they resulted to be resistant to different specialized pathogens. A gene expression analysis of these fruits 

linked the decrease of D-limonene to the upregulation of genes involved in the innate immunity response. 

Additionally, it caused an increase in the accumulation of jasmonates in AS orange peels, explaining their 

resistance to different fungi. Furthermore, this indicates for the first time an inverse correlation between 

volatile terpene accumulation upon fruit development and depletion of JA-mediated defense responses, thus 

stressing the importance of D-limonene for specialized pathogens to establish infections in mature orange 

peels. High D-limonene content in mature orange peels may be a signal for attractiveness of microorganisms 

which might be likely involved in facilitating the access to the pulp of seed dispersal frugivores. 

S05O05 

Improving in vivo antioxidant properties of orange fruits through increased β-carotene content 

Pons E. 1 , Alquézar B. 1 , Rodríguez A. 1 , Martorell P. 2 , Genovés S. 2 , Llopis S. 2 , González N. 2 , Ramón D. 2 , Rodrigo M.J. 3 , 

Zacarías L. 3 , and Peña L. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; 2 Biópolis SL, Cell Biology 

Laboratory, Food Biotechnology Department, Spain; and 3 Instituto de Agroquímica y Tecnología de Alimentos-CSIC (IATA), Departamento 

de Ciencia de los Alimentos, Spain. elponba@ivia.es 

β-Carotene is one of the most efficient carotenoid singlet oxygen quenchers and may interfere in free radical 

oxidation, typical of many degenerative diseases. Besides its activity as protective agent against oxidative 

stress, β-carotene also plays a nutritional role as precursor of vitamin A with twice the efficiency of any 

other pro-vitamin A carotenoid. Orange fruit is an excellent natural dietary source of carotenoids, as well as 

other nutrients and health-promoting compounds such as vitamin C, flavonoids and folic acid. However, the 

most abundant carotenoids present in the pulp of mature oranges are β-β-xanthophylls, while β-carotene is 

hardly detectable. In response to a growing public interest in healthy plant products, this work was aimed 

to strengthen the health benefits of orange fruits by increasing its β-carotene content through metabolic 


engineering. We addressed this goal by blocking the expression of the endogenous β-carotene hydroxylase 

gene (β-CHX), involved in the conversion of β-carotene into xanthophylls, using RNA interference technology. 

Mature fruits of transgenic plants obtained showed changes in carotenoid content and composition in the 

pulp, with an increase in β-carotene accompanied by a general decrease of xanthophylls. The putative 

enhanced capacity of transgenic oranges for protection against oxidative stress and/or degenerative diseases 

may be due to an additive/synergistic effect of increased β-carotene content in a background matrix rich in 

vitamin C and other phytonutrients. This has been assessed by using Caenorhabditis elegans as experimental 

animal model. Results of in vivo assays will be presented and discussed. 

S05O06 

RNA interference against the three Citrus tristeza virus genes encoding silencing suppressors 

confers complete resistance to the virus in transgenic ‘Mexican’ lime plants 

Soler N. 1 , Plomer M. 1 , Fagoaga C. 1 , Moreno P. 1 , Navarro L. 1 , Flores R. 2 , and Peña L. 1 

1Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; and 2Instituto de Biología 

Molecular y Celular de Plantas, CSIC-Universidad Politécnica de Valencia (IBMCP), Spain. soler_nurcal@gva.es 

Citrus tristeza virus (CTV), the causal agent of the most devastating viral disease of citrus, has evolved three 

silencing suppressor proteins acting at intra- (p23 and p20) and inter-cellular level (p20 and p25) to overcome 

host antiviral defense. RNA interference (RNAi), an approach based on using dsRNA to trigger RNA silencing, has 

been widely used for generating transgenic plant resistant against viruses. Considering the important role of p23, 

p20 and p25 in CTV pathogenesis, we transformed ‘Mexican’ lime plants with an intron-hairpin vector carrying 

full untranslatable versions of genes p25, p20, p23 and the 3’-UTR from the CTV strain T36, to attempt silencing 

their expression in CTV-infected cells. Complete resistance to viral infection was observed in three transgenic 

lines, with all their propagations remaining symptomless and virus-free after graft-inoculation with CTV-T36, 

either in the non-transgenic rootstock or directly in the transgenic scion. Accumulation of transgene-derived 

siRNAs was necessary but not sufficient for CTV resistance. When immune transformants were challenged with 

a dissimilar CTV strain the resistance was partially broken, stressing the importance of sequence identity in the 

underlying RNAi mechanism. This is the first evidence that it is possible to achieve full resistance to CTV in a 

highly sensitive citrus host by targeting simultaneously its three viral silencing suppressors through RNAi. 

S05O07 

Further verification of the resistance of ‘C-05’ citron to Citrus Canker disease 

Liu L.P., Li D.Z., Li J.H., Li N., and Deng Z.N. 

National Center for Citrus Improvement (NCCI), Hunan Agricultural University, China. deng7009@163.com 

In the previous screening of citrus genotypes, a Chinese citron (nominated citron ‘C-05’) was found resistant 

to Canker disease (Xanthomonas axonopodis pv. citri). In order to verify its resistance, further tests were 

performed. Another 4 local citron genoytpes from Yunan, including ‘Large’ citron, ‘Small’ citron or ‘Acid’ 

citron, ‘Java’ citron and ‘Indian Large Fruit’ citron, were inoculated in vivo to test their reaction to Xac. The 

assay results indicated that all the 4 citron genotypes were less sensitive to the pathogen than sweet orange, 

but all showed typical symptoms, while citron ‘C-05’ remained symptomless. The results provided further 

evidence that citron ‘C-05’ is not non-host resistant. Growing leaves at different stages of ‘Bingtang’ sweet 

orange (highly susceptible) and citron ‘C-05’ were inoculated by spraying with 10 8 CFU/mL Xac suspensions. 

The leaves of ‘Bingtang’ sweet orange at 1/2 and 1/4 full size were highly susceptible, and leaves at other 

stages were less susceptible; while in the citron, there were only few untypical disease spots on the leaves at 

1/2 and 1/4 full size stages, while no reaction appeared in the other leaf stages. Inoculation with infiltration 

of 10 10 , 10 8 , 10 6 , 10 4 , 10 2 and 10 CFU/mL bacterial solution all caused Canker disease on sweet orange leaves, 

while citron ‘C-05’ showed hypersensitivity reaction. Bacterial growth on the leaf surfaces was observed 

by electronic scanning microscope, and further by the use of a EGFP-labeled pathogen. The bacteria were 

randomly distributed on the leaves, but on the citron leaf, bacterial growth was much less than that on sweet 

orange leaf. Stomata observation revealed that the tested citrus genotypes were substantially similar. The 


S05

S05 

stoma density, size and opening differences between the genotypes were not enough to cause the reaction 

variability related to Xac infection. In conclusion, citron ‘C-05’ is actively resistant to Canker disease. 

S05O08 

Genetic transformation of citrus species aiming to increase tolerance to drought stress 

Carlos E.F., Ariyoshi C., Felício M.S., Shimizu P., Souza G.V., Kudo S.A., Silva L.M., Silva A.J.M., Cação S.M.B., and Vieira L.G.E. 

Instituto Agronômico do Paraná (IAPAR), Laboratory of Biotechnology, Brazil. efcarlos@iapar.br 

Most of the citrus trees grown in Brazil are extensively managed with no irrigation, leaving trees more 

vulnerable to extended dry season, which may reach 90 days without rain in some areas. Thus, utilization 

of rootstocks more tolerant to drought, such as ‘Rangpur’ lime (Citrus limonia), is widely employed, while 

other rootstocks are not. Our laboratory has produced ‘Carrizo’ and ‘Swingle’ rootstocks that accumulate the 

osmoprotectant aminoacid proline, and the present work has continued those efforts aimed to obtain new 

transgenic rootstocks and scions more tolerant to drought stress. We employed Agrobacterium tumefaciens 

carrying a gene encoding a mutant enzyme of P5CS (D1-pyrroline-5-carboxylate synthetase), a key enzyme 

in the biosynthesis of proline, from Vigna aconitifolia, under control of either the constitutive CaMV 35S 

promoter, or the stress induced RD29A promoter. We worked with sweet orange cultivars (Citrus sinensis) 

and trifoliate rootstocks (Poncirus trifoliata cv. ‘Flying Dragon’ and P. trifoliata cv. ‘Rubidoux’). Two sweet 

orange plantlets were micropropagated and further acclimated in greenhouse conditions. One of these trees 

was PCR positive for the transgenes and presented a concentration of free proline 2.6 times higher than 

its non-transgenic control plant. Four plantlets of juvenile ‘Flying Dragon’ were also obtained and trifoliate 

‘Rubidoux’ plantlets are now under selection procedures. 

S05O09 

Targeted cybridization in citrus and transcript profiling of a male sterile cybrid pummelo 

containing cytoplasm from satsuma mandarin 

Guo W.W. 1 , Zheng B.B. 1 , Xiao S.X. 1 , Grosser J.W. 2 , and Deng X.X. 1 

1 Huazhong Agricultural University, Key Laboratory of Horticultural Plant Biology, Ministry of Education, China; and 2 University of 

Florida, Citrus Research and Education Center, USA. guoww@mail.hzau.edu.cn 

Seedlessness is an elite fruit quality trait. By symmetric fusion of embryogenic callus protoplasts of satsuma 

mandarin and mesophyll protoplasts of elite seedy cultivars, diploid cybrid plants containing sterile cytoplasm 

from satsuma were regenerated and characterized from several fusions, and the cybrid pummelo between 

satsuma ‘Guoqing No. 1’ and ‘Hirado Buntan’ pummelo showed male sterile trait. To gain new insight into 

the underlying mechanism, the nuclear gene expression profiles of floral buds of the cybrid with that of 

fertile pummelo were compared by RNA-Seq. Gene expression profiles which identified a large number of 

differentially expressed genes were captured at both petal and stamen primordia distinguishable stages. In 

addition, agreeable with flower morphology of the cybrid, expression of PISTILLATA (PI) was reduced in stamenlike 

structures, even though it was restricted to correct floral whorls. Down-regulated expression of APETALA3 

(AP3) coincided with that of PI. These finding indicated that, due to their whorl specific effects in flower 

development, citrus class-B MADS-box genes likely constituted ‘perfect targets’ for CMS retrograde signaling, 

and that dysfunctional mitochondria seemed to cause male sterile phenotype in the cybrid pummelo. 

S05O10 

In vitro anther culture of several cultivars of Citrus sinensis and Citrus clementina 

Cardoso J.C. 1 , Abdelgallel A. 2 , Chiancone B. 2 , Rocha Latado R. 3 , Lain O. 4 , Testolin R. 4 , and Germanà M.A. 2 

1 Centro APTA Citros Sylvio Moreira - Instituto Agronômico, Cordeirópolis, Centro de Energia Nuclear na Agricultura - Universidade 

de Sao Paulo, Brasil; 2 Facoltà di Agraria. Università degli Studi di Palermo, Dipartimento DEMETRA, Italy; 3 Centro APTA Citros Sylvio 

Moreira - Instituto Agronômico, Cordeirópolis, Instituto Agronômico de Campinas, Brasil; and 4 Università degli Studi di Udine. 

Dipartimento di Scienze Agrarie e Ambientali, Italy. mariaantonietta.germana@unipa.it 

Citrus breeding goals can be achieved by traditional (hybridization, selection, mutation) or biotechnological 

methods. Efficient procedures of in vitro regeneration are required, in conjunction with the recent techniques 

of cellular and molecular biology, to achieve significant improvement in a brief time. Moreover, particularly in 


citrus, somatic embryogenesis is an efficient method of plant regeneration and embryogenic callus is valuable 

for propagation as well as for genetic improvement. Anther culture, among the in vitro regeneration systems, 

is a widespread method to produce haploids (Hs) and doubled-haploids (DHs), drastically reducing the time 

needed to produce homozygous lines compared to conventional breeding methods, that include several 

generations of self-pollination. In addition, in vitro anther culture is also utilized to obtain somatic embryos 

and clonal plant propagation in many woody plants. Actually, in vitro anther culture is, in citrus, an efficient 

approach to obtain both gametic and somatic embryogenesis. In this study, anther culture has been applied 

to several citrus genotypes: four cultivars of C. sinensis and two of C. clementina, testing two temperature 

shocks. The strong influence of the genotype on the response of anthers in vitro cultured has been confirmed. 

Actually, the same treatments applied to the explants in culture resulted in the production of gametic 

embryos in clementines and of somatic embryos in sweet oranges. Clementine confirmed its tendency to 

regenerate homozygous and tri-haploids embryos and plantlets. Further studies should be performed, in 

other citrus genotypes aimed to obtain in vitro regeneration procedures, suitable for different applications, 

as new opportunities for genetic improvement and for the innovation in propagation methods. 

S05O11 

Bioethanol production from mandarin (Citrus unshiu) peel waste 

Choi I.S. 1 , Wi S.G. 1 , and Bae H.J. 2 

1 Bioenergy research center (BRC), Department of Wood Science and Landscape Architecture, Chonnam National University, South 

Korea; and 2 Bioenergy resecenter (BRC), Department of Bioenergy Science and Technology, Chonnam National University, South 

Korea. is.troy@hotmail.com 

Mandarin peel waste (MP), waste biomass recovered after juice extraction, is the main mandarin juice process 

waste. In this study, MP was studied for the potential to produce bioethanol. We designed a new popping 

pretreatment method to produce ethanol from MP. Popping pretreatment was performed at 150°C for 10 min 

without chemical treatment. Popping pretreatment reduced the size of MP particles to less than 1 mm and 

decreased the concentration of D-limonene, a yeast fermentation inhibitor, from 0.21% to 0.01%. Enzymatic 

hydrolysis of pretreated MP was performed in sodium acetate buffer (50 mM and pH 4.8) at 45°C for 6 h, 

and the total saccharification rate was approximately 95.6%. The vacuum evaporation process increased the 

fermentable sugar concentration to 10%. Subsequent fermentation at 30°C at pH 5.0 for 12 h in a laboratory 

bioreactor increased the ethanol yield to 90.6%, compared to 78% at 36 h from raw MP. 

S05P01 

Screening and analyzing the root-specific genes of Poncirus trifoliata 

Yao L.X., Chen S.C., He Y.R., Lei T.G., Xu L.Z., Liu X.F., and Peng A.H. 

Citrus Research Institute, Chinese Acadamy of Agricultural Science (CRIC), China. syaolixiao@126.com 

Poncirus trifoliata is a close relative of citrus species and has been widely used as a rootstock for citrus 

production in China. To isolate root-specific genes from this good genetic source, a root cDNA library of P. 

trifoliata was constructed by polymerase chain reaction (PCR)-based suppressive subtractive hybridization 

(SSH). The cDNA of seedling roots was used as a tester and cDNA of leaves was used as a driver. A total of 1362 

randomly picked clones were sequenced, and 1177 sequences with over 100 base pairs were obtained. The 

majority of these expressed sequence tags (ESTs) showed sequence homology to previously identified genes 

in GenBank, which came from Citrus sinensis (34.5%), Populus trichocarpa (19.1%), Ricinus communis (16.2%) 

and Vitis vinifera (12.2%). The ESTs with gene ontology took part in biology processes such as metabolic process 

(29.8%), cellular process (19.8%), biological regulation (9.8%), developmental process (8.6%), and response 

to stimulus (8.4%), with the biological function of binding (42.1%), catalytic activity (36.6%), transcription 

(8.6%), transporter activity (5.1%) and so on. Through clusting the ESTs with DNAstar software, 455 unigenes 

were accepted, including 121 contigs and 334 singlets. 53 unigenes were selected and analyzed by real time 

RT-PCR. Singlet 52, contig 56, singlet 297, contig 22, singlet 86, contig 28, and singlet 283 showed significantly 

higher expression in roots than in leaves. As well, the full-length cDNA sequences and DNA sequences of 

these genes were obtained by RT-PCR and PCR. Singlet 52 and contig 56 belong to cytochrome P450 family, 

and were named as CYP88A36 and CYP88A37, respectively by Cytochrome P450 Nomenclature Committee. 

Singleton 297, contig 22, and singleton 86 belong to bet_v_I protein family. 


S05

S05 

S05P02 

Comprehending crystalline β-carotene accumulation by comparing engineered cell models and 

natural carotenoid-rich system of citrus 

Cao H.B., Zhang J.C., Xu J.D., Ye J.L., Yun Z., Xu Q., Xu J., and Deng X.X. 

Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, China. 

xuqiang@mail.hzau.edu.cn 

Citrus fruits, which exhibit extensive diversity of carotenoid patterns, can serve as a unique system to improve 

the understanding of carotenogenesis. Herein, we engineered embryogenic calli from four citrus genotypes 

as engineered cell models (ECMs) by overexpressing a bacterial phytoene synthase gene (CrtB). Ripe flavedos 

(the colored outer layer of citrus fruits) were offered as a comparative system to the ECMs. In the ECMs, 

carotenoid patterns showed diversity depending on the genotypes and produced additional carotenoids, 

such as lycopene, that were absent from the wild-type lines. However, the carotenoid pattern in the ECMs 

of one genotype seems not to correlate with that in its flavedo. In the ECMs, there emerged a favored β,βpathway 

characterized by a striking accumulation of β-carotene, which was dramatically unique from those in 

the wild-type calli and ripe flavedos. Unlike flavedos that contained a typical chromoplast development, the 

ECMs sequestered most carotenoids in the amyloplasts in crystal form, which led the amyloplast morphology 

to show chromoplast-like profile. Transcriptional analysis revealed a markedly flavedo-specific expression of 

β-carotene hydroxylase gene (HYD), which was suppressed in the calli. Coexpression of CrtB and HYD in the 

ECMs confirmed that HYD predominantly mediated the preferred carotenoid patterns between the ECMs and 

flavedos, and also revealed that the carotenoid crystals in the ECMs were majorly composed of β-carotene. 

S05P03 

Analyses of Expressed Sequence Tags (ESTs) of ‘Barnfield’ navel orange via constructing of a 

subtractive cDNA library between oleocellosis and healthy rind 

Wei Z.X., Hong L., Cheng C.F., Wu C.Q., and Qi J.R. 

Chongqing Academy of Agricultural Sciences (CAAS), Fruit Research Institute, China. chengchf@hotmail.com 

A cDNA suppression subtractive hybridization (SSH) library was successfully constructed, which was synthesized 

from RNA extracted from a between oleocellosis and healthy rind of ‘Barnfield’ navel orange. Results showed 

that most of the clones had inserting fragments which length ranged from 100 bp to 700 bp. 292 ESTs were 

successfully sequenced from 300 of positive clones. Among the ESTs, 205 ESTs, involving in 105 genes, were 

found sharing homology with known genes, while the others did not show homology with known genes. 

These ESTs were mainly involved in metabolic pathways, biosynthesis of secondary metabolites, microbial 

metabolism in diverse environments, drug metabolism, phenylpropanoid biosynthesis, phenylalanine 

metabolism, naphthalene degradation, beta-lactam resistance, penicillin and cephalosporin biosynthesis and 

glyoxylate and dicarboxylate metabolism. Relative quantitation of expression of a number of genes, analyzed 

by real-time PCR, also confirmed the patterns predicted by SSH. 

S05P04 

Control of flowering time in citrus through ectopic overexpression of flowering locus T (FT) and 

apetala1 (AP1) from sweet orange 

Rodríguez A., Cervera M., and Peña L. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain. arodrig@ivia.es 

Citrus trees have a long juvenile phase that delays their reproductive development by more than 6 years. 

This represents a major obstacle for citrus breeding. The key genes regulating floral transition have been 

studied extensively in species such Arabidopsis thaliana and poplar. In recent years, a growing number of 

genes related to flowering have been identified in crop species. With the aim of accelerating their flowering 

time, we have transformed juvenile citrange and sweet orange plants to constitutively overexpress the sweet 

orange homologues of A. thaliana genes flowering locus T (FT) and apetala1 (AP1), which have been shown 

to accelerate the onset of flowering in a number of plant species including citrus. Both types of transgenic 


citrus plants produced fertile flowers and fruits as early as the first year after genetic transformation. They 

have been characterized at the phenotypical and molecular level and compared to transgenic citrus plants 

over-expressing FT and AP1 from A. thaliana, previously obtained in our laboratory. Additionally, zygotic and 

nucellar CsFT and CsAP1 seedlings have been obtained, generally showing flowering soon after germination 

in CsFT lines or within months after transformation in CsAP1 lines, thus demonstrating the stability and 

inheritance of this trait. These results offer new tools and possibilities for genetic improvement and functional 

genomics research in citrus species. 

S05P05 

Overexpression of a chromoplast-specific lycopene β-cyclase (β-LCY2) gene in orange fruit 

Alquézar B. 1 , Pons E. 1 , Rodríguez A. 1 , Rodrigo M.J. 2 , Zacarías L. 2 , and Peña L. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; and 2 Instituto de 

Agroquímica y Tecnología de Alimentos-CSIC (IATA), Departamento de Ciencia de los Alimentos, Spain. alquezar_ber@gva.es 

Orange fruit is an excellent natural dietary source of phytochemicals and nutrients (as vitamin C, carotenoids, 

flavonoids and folic acid, among others) contributing to its quality, nutritional value and health benefits. 

In recent years, considerable advances in the understanding of the molecular basis regulating carotenoid 

biosynthesis have been accomplished and biotechnological strategies to modify carotenoid content or 

composition in orange fruits are now feasible. For example, β-carotene (provitamin A) content in orange has 

been increased by blocking the expression of an endogenous β-carotene hydroxylase gene, involved in the 

conversion of β-carotene into xanthophylls. β-lycopene cyclase activity is a key metabolic step in the pathway 

as determinates a branching point for the accumulation of β,β-xanthophylls and may be also implicated 

in lycopene accumulation in some citrus species. Therefore, the chromoplast-specific β-LCY2 gene is an 

excellent candidate for the metabolic engineering of carotenoid biosynthesis and its promoter may be also a 

good target to drive fruit-specific expression. Thus, with the aim of increasing β,β-carotenoid levels in orange 

tissues we are over-expressing β-LCY2 using its own promoter. Transgenic ‘Pineapple’ and ‘Valencia’ oranges 

carrying this construction are being generated. Detailed molecular and biochemical analysis of the transgenic 

lines will allow us to gain insights into carotenoid biosynthesis regulation in citrus. 

S05P06 

Genetic transformation of Citrus sinensis with attacin A gene driven by phloem tissue specific 

promoters for resistance to Candidatus Liberibacter spp. 

Tavano E.C.R. 1 , Harakava R. 2 , Vieira M.L.C. 3 , Mourão Filho F.A.A. 4 , and Mendes B.M.J. 1 

1 Universidade de São Paulo (USP), Centro de Energia Nuclear na Agricultura, Brazil; 2 Instituto Biológico (IB), Secretaria de Agricultura 

e Abastecimento do Estado de São Paulo, Brazil; 3 Universidade de São Paulo (USP), Escola Superior de Agricultura “Luiz de Queiroz” - 

Departamento de Genética, Brazil; and 4 Universidade de São Paulo (USP), Escola Superior de Agricultura “Luiz de Queiroz” - Departamento 

de Produção Vegetal, Brazil. ectavano@cena.usp.br 

Huanglongbing (HLB) associated with sieve tube-restricted bacteria Candidatus Liberibacter spp., is one of 

the most destructive disease affecting citrus. The aim of this study was to produce transgenic sweet orange 

plants (Citrus sinensis) expressing antimicrobial attacin A gene (attA) under the control of phloem tissue 

specific promoters, in order to obtain resistant plants to Candidatus Liberibacter spp. Genetic transformation 

of ‘Hamlin’ and ‘Valencia’ sweet orange cultivars was performed via Agrobacterium tumefaciens. The gene 

construct for genetic transformation included the attacin A gene controlled by either sucrose transporter 

gene (AtSuc2) or phloem protein 2 gene promoters (AtPP2) from Arabidopsis thaliana, or phloem protein 

2 gene promoter (CsPP2) from C. sinensis. Epicotyls segments collected from in vitro germinated seedlings 

were used as explants for genetic transformation. Regenerated shoots were micrografted onto ‘Carrizo’ 

citrange seedlings for plant development. Transgenic plants were identified by PCR analyses. The plants were 

acclimatized and transferred to a greenhouse. Integration of the transgene was confirmed for ‘Hamlin’ and 

‘Valencia’ cultivars containing the AtSuc2, the AtPP2 or the CsPP2 promoters controlling the expression of 

attA. The transgene transcription is been studied by northern blot or RT-qPCR analyses. 

Financial support: FAPESP, CNPq. 


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S05P07 

D-limonene downregulation in transgenic sweet orange provides protection against Citrus Black 

Spot symptoms induced in detached fruits 

Kava-Cordeiro V. 1 , Rodríguez A. 2 , Vicent A. 2 , Glienke C. 1 , and Peña L. 2 

1Universidade Federal do Paraná (UFPR), Genética, Brazil; and 2Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de 

Protección Vegetal y Biotecnología, Spain. vanessagenetica@gmail.com 

Citrus Black Spot (CBS) is a disease affecting sweet orange, lemons and mandarin varieties in Africa, 

Oceania and Americas. In Europe, CBS is a quarantine disease, limiting the import of fresh fruits from 

citrus-producing countries of those continents. CBS is caused by the fungus Phyllosticta citricarpa, which 

induces damages in fruit flavedo affecting their appearance and additionally causing premature fruit 

drop, thus reducing productivity. Its field control is currently based on the use of expensive fungicides. 

CBS symptoms are the consequence of fungal induced cell lyses and collapse around oil cavities. Such 

cells are responsible for the synthesis of essential oil. Orange fruit accumulates mainly terpenes in 

peel oil glands and D-limonene accounts for about 97% of oil glands content. In order to improve our 

understanding on the role of D-limonene and related terpenes in the interaction between orange flavedo 

tissues and the pathogen, we have used a P. citricarpa strain transformed with the reporter gene GFP to 

first develop a procedure to inoculate detached fruits in laboratory conditions and reliably get and follow 

fungal infection and symptoms in sweet orange. This has then served to compare the response to CBS 

challenge of fruits from transgenic orange plants carrying a D-limonene synthase gene in antisense (AS) 

configuration vs. empty vector (EV) transgenic controls. AS downregulation leads to a dramatic decrease 

in the accumulation of D-limonene in fruit peels, being about 80-100 times lower in AS samples than in 

EV transgenic ones. EV and AS transgenic fruits (141 and 140 mature fruits, respectively) were inoculated 

in four points, equally spaced intervals, with 5 µL of a conidia suspension (10 6 ). Fungal infection was 

evaluated daily and resulted to be very low or even absent in AS fruits while P. citricarpa readily developed 

in EV fruits. These results encourage the establishment of field trials with the transgenic events in CBSaffected 

areas. 

S05P08 

Resistance to Citrus tristeza virus in Citrus sinensis transgenic plants 

Muniz F.R. 1 , Harakava R. 2 , Rezende J.A.M. 3 , Moore G.A. 4 , Febres V.J. 4 , Mourao Filho F.A.A. 3 , and Mendes B.M.J. 1 

1Centro de Energia Nuclear na Agricultura/Universidade de Sao Paulo (CENA/USP), Brazil; 2Instituto Biologico de Sao Paulo (IB-SP), 

Brazil; 3Escola Superior de Agricultura Luiz de Queiroz/Universidade de Sao Paulo (ESALQ/USP), Brazil; and 4University of Florida (UF), 

USA. fabianaufla@yahoo.com.br 

Citrus tristeza virus (CTV) control relies mainly on the use of tolerant rootstocks and scion cross protection. 

The aim of this work was to evaluate transgenic C. sinensis lines for resistance to CTV, in order to offer 

another alternative for virus control. Transgenic lines of C. sinensis cv. ‘Valencia’ and ‘Hamlin’ containing 

one of 3 different genetic constructs (pCTV-CP: coat protein gene of CTV; pCTV-CS: conserved sequence 

of CTV; pCTV-dsCP: hairpin with sense and antisense sequences of the CP gene) were evaluated, totalizing 

60 transgenic lines. The lines were grafted into C. limonia and C. aurantium, totaling 360 plants. The 

plants were challenged 4 times with CTV by means of T. citricida. Indirect ELISA using a monoclonal 

antibody against the CTV coat protein or Real-time PCR using primers to amplify CTV genes were used 

to detect the virus. Variation in the virus resistance was observed among different transgenic constructs 

and different clones of the same line. The virus was not detected in 20 clones of different lines even 

after the fourth inoculation. For ‘Hamlin’, it was possible to identify 1 transgenic line (CS9 grafted into 

C. limonia) with no virus multiplication. For ‘Valencia’, 1 clone of each transgenic line CP1, CP2, CP4, 

CP9, CS1, CS8, DS3 and DS10 grafted into C. aurantium, 1 clone of CP7, CS1, CS5, CS10 and DS3 and 2 

clones of CP6, CS6 and CS7 grafted into C. limonia did not amplify the virus genes. This indicates possible 

resistance to the pathogen. 


S05P09 

Production of a recombinant miraculin protein in transgenic citrus cell suspension cultures 

Jin S.B. 1 , Sun H.J. 2 , Kim Y.W. 2 , Bachchu M.A.A. 3 , Yun S.H. 4 , Riu K.Z. 3 , and Kim J.H. 3 

1 Subtropical and Tropical Organism Gene Bank, Jeju National University, Korea; 2 Subtropical Horticulture Research Institute, Jeju 

National University, Korea; 3 Faculty of Biotechnology, College of Applied Life Science (SARI), Jeju National University, Korea; and 

4 Citrus Research Station, National Institute of Horticultural and Herbal Science, Rural Development Administration, Korea. 

kimjh@jejunu.ac.kr 

An efficient system for the production of a recombinant miraculin protein in transgenic citrus plant cells 

was developed. Miraculin is a taste-modifying protein that can transform a sour taste into a sweet taste. A 

miraculin gene containing a N-terminal signal peptide was introduced into navel orange (Citrus sinensis) callus 

cells by Agrobacterium-mediated transformation. Transgenic green color somatic embryos were generated 

on SIM medium containing 25 mg/L hygromycin and then embryogenic callus cell lines were produced from 

green color somatic embryos by using RCIM (Callus Reproduction Induction Medium) medium supplemented 

with 1 mg/L of GA 3 , 34 mg/L of adenine, 5% of sucrose, 500 mg/L of malt extract, and 0.2% of gelrite. The 

insertion of the miraculin gene in the transformants was confirmed by genomic-PCR, using specific primers of 

the miraculin gene. Cell suspension cultures were kept in MT liquid medium, pH 5.2, containing 5% sucrose. 

In order to overproduce the miraculin protein, the transgenic cells were transferred to fresh liquid suspension 

medium at 5% (weight of wet callus/volume of medium) density and were cultured at 15°C with rotation 

speed of 120 rpm. Recombinant miraculin expression and secretion in transgenic citrus suspension cells was 

confirmed by Western blot analysis. The recombinant miraculin protein was secreted into the culture medium 

and formed a disulfide-linked dimer similarly to the native miraculin with the taste-modifying activity. This 

production system could be a good alternative for production of the recombinant miraculin. 

S05P10 

Transgenic sweet orange rootstocks overexpressing a osmotin like PR-5 protein show resistance 

against Phytophthora Foot Rot in the field 

Peris J.E., Vicent A., and Peña L. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain. lpenya@ivia.es 

Phytophthora spp. causes foot rot and gummosis, the most serious soilborne diseases of citrus worldwide. Sweet 

orange (Citrus sinensis) might be an excellent rootstock but it cannot be used as such in many citrus areas due to 

its high sensitivity to Phytophthora spp. The development of sweet orange that possess durable genetic resistance 

provides the best prospect for full recovery of this citrus type as rootstock. A wide range of plant defensive antifungal 

proteins has been identified and is being used in attempts to provide protection via expression in transgenic crops. 

Proteins of the PR-5 group (osmotin and thaumatin-like proteins) have antifungal activity in vitro against fungi 

and oomycetes. We demonstrated the antifungal properties of tomato P23 (PR-5) in vivo by overexpressing the 

PR-5 coding sequence under the control of the 35S promoter from CaMV in sweet orange plants, and testing 

plant response to P. citrophthora infections in excised bark pieces and in potted plants. One transgenic line (9.1a) 

resulted to be clearly resistant in both experiments, while other 9 (including 2.31a) resulted susceptible to P. 

citrophthora as the empty vector transgenic control (2.15). Promising results with transgenic line 9.1a encouraged 

us to conduct a field trial to test resistance to Phytophthora-induced foot rot. Transgenic sweet orange seedlings 

from lines 9.1a, 2.31a and 2.15 were used as rootstocks and non-transgenic clementine mandarin was budded on 

top and used as scion. Thirteen trees per transgenic event were randomly disposed in the field in 2009 and let to 

become naturally infected. Three years after planting, more than 50% of 2.31a and 2.15-trees are showing severe 

foot rot caused by Phytophthora, while all 9.1a trees remain symptomless. 

S05P11 

Evaluation of transgenic oranges expressing the stx IA gene for resistance to Citrus Canker 

Marques V.V. 1 , Miller A.M. 2 , Bagio T.Z. 2 , Souza G.V. 3 , Meneguin L. 2 , Vieira L.G.E. 4 , Pereira L.F.P. 5 , and Leite J.R.R.P. 2 

1 Fundecitrus, Scientific, Brazil; 2 Instituto Agronômico do Paraná (IAPAR), Plant Protection, Brazil; 3 TMG, Scientific, Brazil; 4 Instituto 

Agronômico do Paraná (IAPAR), Biotechnology, Brazil; and 5 Embrapa, Biotechnology, Brazil. viviani@fundecitrus.com.br 

Citrus Canker caused by Xanthomonas citri subsp. citri (Xcc) is an important disease for citrus production 

around the world. Several highly valuable commercial citrus cultivars are moderately to highly susceptible 


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to this disease. Development of transgenic plants for disease resistance in economically important citrus 

cultivars may represent a unique and efficient strategy for control of Citrus Canker. In this work, we report 

the reaction to Citrus Canker of five independent events (STX-3, STX-5, STX-11, STX-12 and STX-13) of sweet 

orange cv. ‘Pera’ (Citrus sinensis), transformed with the vector pST10 containing the antibacterial peptide 

gene stx IA under control of CaMV 35S promoter and the signal peptide from tobacco PR 1a. For inoculation, 

young expanded citrus leaves were injection-infiltrated or sprayed with a suspension of strain 306 of Xcc. 

Reduction in disease incidence was observed for the transgenic events as compared with the non-transformed 

control citrus plants. The lowest levels of disease incidence were observed for the events STX-3 and STX-5. 

Furthermore, significant differences were also observed in disease severity between the transgenic plants 

and the non-transformed control plants. The events STX-3 and STX-12 showed the lowest populations of Xcc 

in the leaf tissue. A slower growth of Xcc was observed in the stx IA transgenic plants, with differences of up 

to 2 log units in bacterial populations between transgenic plants and non-transformed control plants. 

Financial support: Fundecitrus. 

S05P12 

Transgenic ‘Mexican’ lime plants expressing the gene p23 from Citrus tristeza virus (CTV) 

under the control of a phloem-specific promoter display symptoms closely similar to those 

accompanying virus infection 

Soler N. 1 , Fagoaga C. 1 , López C. 2 , Moreno P. 1 , Navarro L. 1 , Flores R. 2 , and Peña L. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; and 2 Instituto de Biología 

Molecular y Celular de Plantas, CSIC-Universidad Politécnica de Valencia (IBMCP), Spain. soler_nurcal@gva.es 

Citrus tristeza virus (CTV) is phloem-restricted in natural citrus hosts. The 23 kDa protein (p23) encoded by the 

virus is a RNA silencing suppressor and an important pathogenicity factor. Constitutive expression of p23 in 

transgenic citrus plants under the control of the 35S promoter incites, in addition to aberrations resembling 

CTV symptoms, others likely related to the ectopic expression of this protein in cells usually not infected by 

the virus. Moreover, transgenic expression of a fragment comprising only the N-terminal 157 amino acids 

(p23Δ158-209) elicit CTV-like leaf symptoms similar to, albeit milder than, those resulting from expression 

of the complete p23 protein. To discriminate between symptoms induced by p23 in CTV infection and other 

pleiotropic effects of this protein, we restricted expression of p23-derived transgenes to phloem-associated 

cells in ‘Mexican’ lime plants by means of the phloem-specific promoter from Commelina yellow mottle virus 

(CoYMV). The complete gene p23 from either the severe T36 or the mild T317 CTV isolates, or the fragment 

p23Δ158-209 from the former, were used. Expression of these constructs in the phloem incited CTV-specific 

symptoms like vein clearing in ‘Mexican’ lime leaves, but not the unspecific symptoms (epinasty, growth cease 

and apical necrosis) observed when p23 was expressed under the control of the 35S promoter. Moreover, vein 

necrosis was exclusively associated to phloem-specific expression of the transgenes derived from CTV T36. 

S05P13 

Efficient deletion of the selectable marker gene from transgenic citrus via the Cre/loxp system 

Zou X.P., Peng A.H., Liu X.F., He Y.R., Xu L.Z., and Chen S.C. 

Citrus Research Institute, Chinese Academy of Agricultural Sciences (CRIC), China. zxping11230@126.com 

Selectable marker genes conferring antibiotic- or herbicide- resistance are in general required to efficiently 

recover transgenic plants from transformed cells during plant transformation. However, the presence of marker 

genes raises public concerns regarding the field release of transgenic plants. Removal of marker genes prevents 

the risk of its release into the environment and hastens the public acceptance of transgenic products. In this 

study, an efficiency system for deletion of a selectable marker gene from transgenic citrus by Cre/loxp siterecombination 

has been constructed via conventional Agrobacterium-mediated transformation. Our results 

showed that about 20% of transformation efficiencies could be obtained using ipt (isopentenyltransferase) 

gene from A. tumefaciens as a selectable marker gene. Molecular analysis demonstrated that 20-100% 

complete deletion occurred in transgenic plants and that Cre/loxp-mediated excision was always precise in 

citrus. This approach provides a reliable strategy for deleting selectable marker genes from transgenic citrus 

after transformation and thus producing marker-free transgenic plants. 


S05P14 

Assessment of pollen-mediated transgene flow in citrus under experimental field conditions 

Pons E. 1 , Navarro A. 1 , Ollitrault P. 2 , and Peña L. 1 


Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), UPR amélioration génétique des espèces à 

multiplication végétative, France. elponba@ivia.es 

Despite potential benefits granted by genetically modified (GM) citrus trees, their release and commercialization 

raises concerns about their potential environmental impact. The transfer via pollen of transgenes to crosscompatible 

cultivars is deemed to be the greatest source for environmental exposure. In this work, three 

different citrus genotypes carrying the uidA (GUS) tracer marker gene (pollen donors) and a non-GM selfincompatible 

contiguous citrus genotype (recipient) were used in conditions allowing natural entomophilous 

pollination to occur. The examination of 603 to 2990 seeds per year showed unexpectedly low frequencies 

(0.17-2.86%) of transgene flow. Paternity analyses of the progeny of subsets of recipient plants using 10 

microsatellite (SSR) loci demonstrated a higher mating competence of trees from another non-GM pollen 

source population that greatly limited the mating chance of the contiguous cross-compatible and floweringsynchronized 

transgenic pollen source. This mating superiority could be explained by a much higher pollen 

competition capacity of the non-GM genotypes, as was confirmed through mixed-hand pollinations, indicating 

that pollen competition strongly contributed to transgene confinement. This is the first study on transgene 

flow in citrus. It provide crucial information on the safety and field performance of GM citrus that can serve 

as a basis for further field trials and as a guide for (case-by-case) regulatory policies. 

S05P15 

Functional analysis of a citrus transcription factor with mature fruit-specific expression using 

transgenic tomato 

Endo T. 1 , Shimada T. 1 , Fujii H. 1 , Sugiyama A. 1 , Nakano M. 1 , Ikoma Y. 1 , and Omura M. 2 

1 NARO Institute of Fruit Tree Science (NIFTS), Citrus Research Division, Japan; and 2 Shizuoka University, Faculty of Agriculture, Japan. 

tomoen@affrc.go.jp 

Citrus fruit changes color drastically at maturation with reduction of chlorophyll and accumulation of carotenoids 

in peel. This color change is known to be suppressed with exogenous gibberellin and, in contrast, promoted with 

ethylene treatment. In order to identify genes regulating metabolisms involving citrus fruit color change, we 

have screened transcription factor genes with the profile as their expression is induced by ethylene and reduced 

by gibberellin treatment in mature fruit peel using a microarray. Among them, a bHLH gene, TF-BFC, with 

mature fruit-specific expression has been selected, introduced and overexpressed in tomato ‘Micro Tom’. Three 

independent transgenic lines with high transgene expression were selected and analyzed. Transgenic plants 

were dwarf, had deep-green and curled leaves and orange-colored fruit. The chlorophyll content in transgenic 

leaves was about two times higher than in controls. Microarray analysis of transgenic plants showed that over 

3,000 genes had significant expression changes (>2-fold) in red fruit, but in green fruit, the number of genes with 

significant expression changes was only about half. Gene homologs probably encoding enzymes of carotenoid 

biosynthesis, such as phytoene synthase, phytoene desaturase, z-carotene desaturase and b-ring hydroxylase 

were shown to be highly expressed in transgenic red fruit, in accordance with the results from RT-PCR analysis. 

These results suggest that TF-BFC induced gene expression of carotenoid biosynthesis and suppressed genes 

involving photosynthesis in transgenic tomato mature fruit, showing important roles in carotenoid biosynthesis. 

S05P16 

Effect of the citrus lycopene β-cyclase transgene on carotenoid metabolism in transgenic tomato fruits 

Guo F., Zhou W.J. , Zhang J.C. , Xu Q. , and Deng X.X. 

Key Laboratory of Horticultural Plant Biology of Ministry of Education (KLHPBME), Huazhong Agricultural University, China. 

guofei_121@163.com 

Lycopene β-cyclase (LYCB) is the key enzyme for the synthesis of β-carotene, a valuable component of the human 

diet. In order to evaluate the effect of constitutively expressing a citrus Lycb-1 gene on carotenoid synthesis, 


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tomato constitutively express Lycb-1 was engineered in this study. The β-carotene level of transformant increased 

4.1 fold, and the total carotenoid content increased by 30% in the fruits. In the transgenic line, the downstream 

α-branch metabolic fluxes were repressed during the three developmental stages while α-carotene content 

increased in the ripe stage. Microarray analysis in the ripe stage revealed that the constitutive expression of Lycb- 

1 affected a number of pathways including the synthesis of fatty acids, flavonoids and phenylpropanoids, the 

degradation of limonene and pinene, starch and sucrose metabolism and photosynthesis. This study provided 

insight into the regulatory effect of Lycb-1 gene on plant carotenoid metabolism and fruit transcriptome. 

S05P17 

Role of the sweet orange tau glutathione transferases (csgstu) in transgenic tobacco plant 

detoxification from xenobiotics 

Lo Cicero L. 1 , Madesis P. 2 , Tsaftaris A. 3 , Lo Piero A.R. 4 

1 University of Catania (DISPA), Dipartimento di Scienze delle Produzioni Agrarie e Alimentari, Italy; 2 The Centre for Research and 

Technology Hellas (CERTH), Institute of Applied Biosciences, Greece; 3 The Centre for Research and Technology Hellas (CERTH), 

Institute of Agrobiotechnology, Greece; and 4 University of Catania (DISPA), Dipartimento di Fitopatologia e genetica vegetale, Italy. 

lociceroluca1981@libero.it 

The glutathione S-transferases (GSTs) catalyse the attack of glutathione (GSH) on a variety of hydrophobic 

toxic chemicals. The conjugation of GSH to such molecules increases their solubility and facilitates further 

metabolic detoxifying processes. Two csgst genes (gstu1 and gstu2) encode for proteins which differ only for 

three amino acids located in the hydrophobic co-substrate binding site (gstu1: R89, E117, I172; gstu2: P89, 

K117, V172). Previously, site-directed mutagenesis experiments generated several cross-mutate enzymes and 

among them the GST-RKV mutant derives from the P89R substitution upon the gstu2 isoform. In this work, 

both wild-type (gstu1 and gstu2) and the GST-RKV mutant were incorporated into the tobacco genome under 

the control of the strong constitutive CaMV 35S promoter via Agrobacterium mediated transformation. PCR 

and Southern blot analysis was performed to confirm the presence of the nptII gene only in the genomic DNA 

from transformed tobacco plants. The expression of the transgenes was also assessed by RT-PCR experiments. 

The GST activity of tobacco leaves transformed with wild type GSTs turned out to be similar with that exhibited 

by untransformed plants, whereas plants harbouring the GST-RKV mutant gained a 2-fold increase of the GST 

activity assayed against several pollutants, thus suggesting that the RKV-transformed tobacco plants acquired 

novel favourable traits which might provide a more efficient contribution in the detoxification system. 

S05P18 

An alternative transformation method in citrus using cell-penetrating peptides (CPPs) 

Jensen S.P., Febres V.J., and Moore G.A. 

University of Florida (UF), Plant Molecular and Cellular Biology, United States of America. jensensp@ufl.edu 

Citrus transformation is typically Agrobacterium tumefaciens-mediated, in which citrus tissues are cultivated 

with the bacterium and regenerated on selection media. Part of the bacterial plasmid, with the gene of 

interest and resistance genes, is then inserted into the citrus genome. Due to the slow growth of citrus, 

this long process must be optimized for each cultivar and ultimately the transformation efficiency in citrus 

is substantially less than with other model systems. Commercialization of transgenic citrus is even slower 

because of the regulations on genetically modified produce worldwide. In order to decrease the dependence 

upon bacterial transformation and increase transformation efficiency, we propose an alternative method of 

transformation using cell penetrating peptides (CPPs) that does not involve Agrobacterium. CPPs are positively 

charged short amino acid sequences able to simultaneously bind proteins and nucleic acids and deliver them 

across cellular membranes and cell walls. CPPs are used currently in plants in transient expression assays and 

gene silencing, but have not been used in citrus or in stable transformation experiments. We have developed 

a standard method for the transient expression of reporter genes (gus and gfp) in citrus. Our data indicate 

that up to 50% of treated explants express GUS when CPPs are used alone. Several optimization steps have 

been tested and the efficiency is increased to 100% when CPPs are used in conjunction with a lipid reagent. 

We have transformed several explant segments which survived kanamycin selection, produced shoots and 

roots, and were planted. PCR and reporter gene analysis will confirm stable integration. Further experiments 

with CPPs, comprising RNAi and protein trafficking, will also be performed. 


S05P19 

Establishment of a transient expression system in citrus via agro-infiltration 

Dai S.M., Li F., Yan J.M., Li D.Z., Li R.H., and Deng Z.N. 

Hunan agricultural university, China. dsm531@126.com 

Genetic transformation is a traditional tool for both functional genomics and molecular breeding in plants, 

but it is time-consuming and low efficient in citrus due to its low transformation rate. It is essential to 

establish a transient expression system to speed-up gene function identification. Here we report a gene 

transient expression by using agro-infiltration for citrus. A full comparison was performed between different 

parameters including Agrobacterium injection buffer solutions, expression vectors and concentrations of 

the bacterial solution. Results showed that in the transient expression system with injection buffer solution 

composed of 50mM MES pH5.6, 10mM MgCl 2 , 150µM acetosyringone, pCAMBIA-2301 expression vector and 

Od 600 = 0.4 as ideal concentration of bacterial solution, a foreign gene could be effectively expressed in citrus. 

With this system, it is possible to analyze gene function in citrus rapidly. 

S05P20 

Improvement of transformation efficiency in citrus 

Yang L. 1 , Hu W. 1 , Xie Y.M. 1 , Li Y. 2 , and Deng Z.N. 1 

1 National Center for Citrus Improvement (Changsha) (NCCI), Hunan Agricultural University, China; and 2 Department of Plant Science 

(DPS), University of Connecticut, USA. yangli526526@126.com 

Internodal stem segments from citrus seedlings have been widely used as explants in transformation 

research, due to their ability of easy regeneration. Since 1990, genetic transformation has been applied on 

different citrus species including sweet oranges (Citrus sinensis), mandarins (C. reticulata), trifoliate orange 

(Poncirus trifoliata), sour orange (C. aurantium), pummelo (C. grandis), citrange (C. sinensis × P. trifoliate), 

and lemon (C. limon) in our biotechnology program. But the successful transformation rates are low, thus 

impeding the realization of transgenic cultivar breeding. Consequently, the development of an efficient 

transformation system becomes essential. A series of factors was tested to improve transformation rates 

in sweet orange and kumquat (Fortunella crassifolia). The results indicated that using seedlings grown 

20 to 25 days in dark and 10 days in light as explants could provide higher frequencies of GUS positive 

regenerated buds. Adding auxin and placing sterile filter paper during the co-cultivation estimulated 

the growth of regenerated buds, and increased about 13% the frequency of GUS positive regenerated 

buds. Lower pH and co-cultivation temperature under acetosyringone induction enhanced transformation 

competence. With all the improved factors, the transformation rate was in average 18.6%, and in the best 

case, the transformation rate reached 23%. 

S05P21 

Improvement of genetic transformation with mature explants of sweet orange (Citrus sinensis) 

Xie Y.M. 1 , Yang L. 1 , Hu W. 1 , Li Y. 2 , and Deng Z.N. 1 

1 National Center for Citrus Improvement (Changsha) (NCCI), Hunan Agricultural University, China; and 2 Department of Plant Science 

(DPS), University of Connecticut, USA. xym9366@163.com 

High level of contamination, low morphogenetic potential and recalcitrance to Agrobacterium tumefaciens 

infection are the main problems in the transformation of adult citrus tissues. A series of experiments was 

performed to solve these problems. ‘Newhall’, ‘Succari’ and ‘Bingtang’ sweet orange cultivars were tested. 

Adult shoots from the 3 cultivars were grafted and re-grafted on Poncirus trifoliata rootstocks in the 

greenhouse. Internodal stem segments of about 1 cm in length from 30-day old mature shoots of were taken 

as explants. Through re-grafting mature shoots, the contamination rate of explants was much lower, even 

0%. The adventitious bud regeneration rate was obviously improved, approximately 80%, 67.5% and 55% in 

‘Succari’, ‘Bingtang’ and ‘Newhall’ sweet oranges, respectively. After Agrobacterium infection, the highest 

adventitious bud regeneration rate of ‘Bingtang’ sweet orange reached 25%. The transformation rate was 

3.8%, 4.6% and 3.2% in ‘Succari’, ‘Bingtang’ and ‘Newhall’ sweet orange cultivars, respectively. The ‘gene- 


S05

S05 

deletor’ technology is an efficient system to remove all the functional transgenes from the pollen and seeds of 

the transgenic plants, activated by specific promoters. Two ‘gene-deletor’ constructs containing pLF_polB-FLP 

and pLF_polL-Cre boxes, respectively, were transferred into mature explants of sweet orange by the improved 

procedures, and 10 transformed plants were confirmed to be positive by GUS expression and PCR analysis. 

The transformed plants will be tested for the gene-deletor function later on. 

S05P22 

Efficient propagation and rooting of citrus rootstocks adult explants using different basal 

medium and plant growth regulators 

Tallón C.I., Porras I., and Pérez-Tornero O. 

Instituto Murciano de Investigación y Desarrollo Agrario y Alimentario (IMIDA), Citricultura, Spain. olalla.perez@carm.es 

The influence of the basal medium and different plant growth regulators on the efficient micropropagation 

of nodal explants from mature trees of sour orange and ‘Cleopatra’ mandarin citrus rootstocks was studied. 

The preference of all two citrus rootstock shoot cultures for high-salt media, like MS or DKW, was observed. 

Several combinations of BA and AD, KIN or GA were made in an attempt to optimize the proliferation phase. 

The addition of BA and AD to the culture medium improved the proliferation in sour orange or ‘Cleopatra’ 

mandarin in the same way as BA/GA. The use of different combinations of BA/KIN did not improve any of 

the studied variables. The transfer of in vitro shoots to rooting media, containing different concentrations of 

IBA and IAA, produced complete plantlets of ‘Cleopatra’ mandarin, but very low rooting percentages in sour 

orange were obtained. To improve the rooting results different combinations of NAA and IBA were tested and 

higher rooting percentages than in the IBA/IAA combinations were produced. In sour orange percentages 

nearly 100% of rooted explants were obtained. 

S05P23 

Optimization of in vitro organogenesis and plantlet regeneration of sweet orange from mature tissue 

Castro L.M. 1 , Mendes B.M.J. 2 , and Mourão Filho F.A.A. 3 

1 Universidade de São Paulo (USP), Departamento de Produção Vegetal, Brazil; 2 Universidade de São Paulo (USP), Centro de Energia 

Nuclear na Agricultura - Laboratório de Biotecnologia Vegetal, Brazil; and 3 Universidade de São Paulo (USP), Departamento de 

Produção Vegetal, Brazil. liviamdecastro@yahoo.com.br 

The use of mature tissue for citrus genetic transformation is important for the precocious evaluation of the 

genetically modified characteristics. However, an efficient organogenesis protocol with high rates of plant 

regeneration is necessary. This work aimed to optimize a protocol for in vitro organogenesis of ‘Hamlin’, ‘Pera’, 

and ‘Valencia’ sweet orange cultivars (Citrus sinensis) using as explant internodal segments collected from 

adult plants cultured in greenhouse. Organogenesis was induced by culturing internodal segments in Petri dish 

(100 x 15 mm) contanining MS medium supplemented with sucrose (30 g∙L -1 ) and different concentrations of 

benzylaminopurine (BAP; 0.0, 1.0, 2.0, 3.0, and 4.0 mg∙L -1 ). The material was incubated in the dark at 27°C 

± 2°C for 6 to 8 weeks. After adventitious bud development, the shoots were transferred to Petri dish (100 x 

20 mm) containing MS medium with half concentration of BAP and incubated under 16-h photoperiod. The 

highest percentage of responsive explants was obtained with explants cultured in medium supplemented 

with 1 mg∙L -1 BAP. The explant responsiveness varied among cultivars. ‘Hamlin’ was the most responsive 

followed by ‘Valencia’ and ‘Pera’. Adventitious shoots were grafted ex vitro onto decapitated ‘Rangpur’ lime 

rootstocks (C. limonia). This protocol will be utilized for citrus mature tissue genetic transformation. 

S05P24 

Applications of citrus shoot-tip grafting in vitro 

Juárez J., Aleza P., and Navarro L. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain. jjuarez@ivia.es 

The main application of shoot-tip grafting (STG) is the control of graft-transmissible pathogens that requires 

the use healthy trees in the new plantings. The routine application of STG using 0.1-0.2 mm shoot tips is very 


efficient for elimination of all citrus graft-transmissible pathogens from local or imported varieties. It has 

allowed worldwide the recovery of hundreds of healthy cultivars and the planting of hundreds of millions of 

healthy certified trees. Only in Spain about 135 million certified nursery plants propagated from micrografted 

plants have been planted. STG is also a very useful technique for regeneration of elite genotypes in several 

areas of research. In vitro grafting for these purposes may be done using larger shoots (up to 1 cm). STG is 

being routinely used for the following purposes: (i) Regeneration of somatic hybrids from embryos difficult to 

germinate; (ii) Regeneration of plants from irradiated shoots to produce seedless varieties; (iii) Regeneration 

of plants from haploid embryos that are very difficult to germinate. STG was used to regenerate the 

‘Clemenules’ haploid plant that has been used by the International Citrus Genome Consortium to sequence 

the whole citrus genome; (iv) Production of stable tetraploid plants of monoembryonic genotypes, which are 

very useful for triploid breeding; (v) Regeneration of transgenic plants from shoots that are very difficult to 

root in vitro. STG has become a routine application in citrus genetic transformation. 

S05P25 

Microshoot tip grafting in vitro-a technique for establishment of disease free scion bank of Citrus 

reticulata var. ‘Khasi’ mandarin 

Sanabam R.S., Huidrom S.D., and Handique P.J. 

Institute of Bioresources and Sustainable Development (IBSD), Medicinal Plants and Horticultural Resources Division, India. 

sbnm_rakesh@yahoo.com 

This study has been carried out to produce viral disease free scion bank of ‘Khasi’ mandarin (Citrus reticulata) 

using four citrus cultivars namely ‘Kachai’ lime, ‘Champra maounthabi’, ‘Solom’ and ‘Phouheiree’ through 

micrografting techniques as viral disease affects the longevity of citrus orchards and quality of fruits. Success 

of micrografting depends on the type of cut for scion insertion, age of seedlings of rootstock, conditions of 

light or darkness, concentration of sucrose used and also on cultivar used for micrografting. Frequency of 

success improved considerably from 36.24% success at 3% sucrose to 40.05 % success at 6% sucrose with 0.5 

mg/L benzyl amino purine (BAP) in Murashige and Tucker (MT) liquid media. Response of micrografting also 

significantly improved when inverted T type of cut was used for scion insertion giving 37.07% compared to 

28.13% of success in that of wedge type of cut. Highest rate of success was obtained in ‘Champra maounthabi’ 

with success rate of 40.74% followed by ‘Phouheiree’, ‘Solom’ and ‘Kachai’ lime of 34.26%, 32.24% and 27.53% 

success respectively. Analysis of 8-10 months old micrografted plants for the presence of graft-transmissible 

Citrus tristeza virus (CTV) following double antibody sandwich-enzyme linked immunosorbent assay (DAS- 

ELISA) technique was performed giving negative results for the virus. 

S05P26 

Elimination of Spiroplasma citri by somatic embryogenesis from citrus stigma and style culture: 

preliminary results 

Frasheri D. 1 , Moujahed R. 1 , Djelouah K. 1 , Carra A. 2 , Carimi F. 2 , Valentini F. 1 , and D’Onghia A.M. 1 

1 CIHEAM-Mediterranean Agronomic Institute of Bari (CIHEAM-MAIB), Integrated Pest Management, Italy; and 2 Consiglio Nazionale 

delle Ricerche, UOS Palermo (CNR-UOS Palermo), Istituto di Genetica Vegetale, Italy. frasheri@iamb.it 

Spiroplasma citri, the causal agent of Citrus Stubborn disease, is spread by infected budwood and, in nature, 

by phloem-feeding homoptera insects, predominantly leafhoppers. This pathogen can be usually eliminated 

by shoot-tip grafting. In this work, somatic embryogenesis from stigma and style culture, which proved to be 

effective in the elimination of several infectious agents of citrus, has been firstly applied in the elimination of 

this pathogen. Flowers were collected from an infected Egyptian source of sweet orange ‘Washington’ navel. 

Pistils were tested by DAS ELISA using monoclonal antibodies (SEDIAG-INRA, France) and PCR using specific 

primers targeting the spiralin; 5 out of 70 pistils were found infected by S. citri. About 75 flowers were surface 

sterilized in ethanol and vertically placed in Petri dishes in contact with Murashige and Skoog (MS) medium 

supplemented with 6- benzylaminopurine. Explants were in vitro cultured and subculturing was carried out 

every 3-4 weeks. Thirty-nine explants produced callus about 20-30 days after culture initiation, twenty-eight 

of which regenerated embryos 4 months later. Embryos were individually cultured in test tube and in vivo 

acclimatized after 6 months from embryo formation by minigrafting regenerated plants onto 6 month-old 


S05

S05 

sour orange seedlings. The embryogenic callus and leaf midveins of 3 month-old regenerated plants were 

cultured in SP4 and LD8 media, which were used for PCR assays. Results of sanitary tests showed a 30% 

infection rate in the callus while no infection was detected in the regenerated plants. 

S05P27 

The study on callus induction of citrus anther culture in vitro 

Luo J.Q., Xu J.G., Wang P., Ke F.Z., and Nie Z.P. 

Zhejiang Citrus Research Institute (ZCRI), Research, China. xujg@mail.zaas.ac.cn 

Anther culture has special significance for breeding of citrus. It has been proved as one effective way of 

obtaining haploid and heteroploid materials. Citrus anthers mostly at middle and late uninucleate stage were 

cultured to study the influence of genotype, hormone composition of the culture medium, cold pretreatment, 

culture temperature and light conditions on callus formation. Results showed that the sequence of increasing 

difficulty on callus induction started with ‘Meyer’ lemon (Citrus limon), followed by ‘439’ tangor (C. reticulata 

× C. sinensis), calamondin (C. madurensis), ‘Changshou’ kumquat (Fortunella obovata) and ‘Zaoju’ (Citrus 

compressa), regarding genotype. MT 6-BA 0.5mg/L, TDZ 0.2 mg/L, 2,4-D 0.2 mg/L, sugar 30-40g/L was 

determined to be a suitable culture medium for anther callus induction of citrus types. Cold pretreatment at 

6±2°C for 5-10 d, and then cultivation at 23-25°C were beneficial for callus induction of citrus anthers in vitro. 

Cultivation in darkness was also helpful to mitigate the maturation and browning of anthers, promoting their 

survival and then callus induction. More than 3000 citrus calli were obtained during 2 years of anther culture, 

more than 2900 pieces from ‘Meyer’ lemon, and 35, 39, 2 and 2 callus pieces from ‘439’ tangor, calamondin, 

‘Changshou’ kumquat and ‘Zaoju’, respectively. ‘Meyer’ lemon calli is being subcultivated to study ploidy, 

embryoid induction and plant regeneration. 

S05P28 

Induction of tangerine embryogenic calli from unfertilized or immature ovules 

Machado M.P. 1 , de Bona C.M. 2 , and Biasi L.A. 1 

1 Federal University of Parana (UFPR), Plant Production, Brazil; and 2 Agronomic Institute of Parana (IAPAR), Pomology, Brazil. 

debona@iapar.br 

Triploid hybrids may be obtained by interploid crosses between diploid and tetraploid individuals, but it is 

difficult to obtain tetraploid lineages because of the high frequency of chimerical polyploids. It is possible 

to induce polyploidy in embryogenic calli or cell suspensions by using antimitotics. Embryogenic calli may 

be obtained from abortive, unfertilized or fertilized ovules, or from nucellus. Aiming to establish suspension 

cell cultures for further treatment with antimitotics, ovules of ‘Ponkan’, ‘Montenegrina’, ‘Mexerica-do-Rio’ 

and ‘Cravo’ tangerines were used. After asepsis in sodium hypochlorite (3:1) solution, the ovules were 

inoculated on Petri dishes (100 x 15 mm) (20 ovules per plate) containing 20 mL MT basal medium, 500 mg∙L -1 

malt extract, 50 g∙L -1 saccharose and 5,0 mg∙L -1 kinetin and maintained in the dark at 25°C ± 2°C, being 

subcultivated every four weeks. The experimental design was completely randomized with four repetitions. 

After two months, the percentage of embryogenic calli and somatic embryos was recorded. The data were 

submitted to variance analysis and mean deviation was calculated. Calli and embryo induction occurred at 

the 8th week. ‘Mexerica-do-Rio’, ‘Cravo’, ‘Ponkan’ and ‘Montenegrina’ presented 25%, 35%, 15% and 9% 

calli, respectively. Somatic embryos developed rapidly. ‘Ponkan’ and ‘Montenegrina’ presented the highest 

percentage of somatic embryos, 45% and 30%, respectively. The different cultivars presented different 

responses to calli and somatic embryos induction. 

S05P29 

Chromosome instability in ‘Carrizo’ citrange × Citrus macrophylla somatic hybrids 

Pensabene G. 1 , Ruíz M. 1 , Aleza P. 1 , Olivares-Fuster O. 1 , Ollitrault P. 2 , and Navarro L. 1 


Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), BIOS, France. lnavarro@ivia.es 

Somatic hybridization by protoplast fusion is a very useful technique for citrus rootstock breeding. Indeed, it 

theoretically allows the accumulation of all genes of the parents, irrespective of their heterozygosity level and 


therefore the addition of complementary dominant traits. In this work, protoplasts were isolated from callus of 

Citrus macrophylla and from leaves of ‘Carrizo’ citrange (C. sinensis × P. trifoliata). Chemical, electro-chemical 

and electric fusions were performed and the ploidy of regenerated plants was evaluated by flow-cytometry. 

Five tetraploid plants, one pentaploid plant, one mixoploid (3x-6x) plant and one heptaploid plant were 

recovered. All these plants were analyzed with SSR and SNP markers, distributed in the nine chromosomes of 

citrus. Cytoplasmic genomes were characterized with chloroplastic and mitochondrial markers. Mitochondrial 

genome was inherited from C. macrophylla for all plants while segregation was observed for the chloroplastic 

genome. Nuclear genome analysis revealed the loss of parental alleles in most of the regenerated plants. In 

tetraploids, it affected mainly C. macrophylla alleles while P. trifoliata alleles were mostly lost in 5x and 7x 

plants. The results indicate chromosome instability in this complex intergeneric combination with apparent 

non random loss of some chromosome fragments. Two allotetraploid somatic hybrids have been selected for 

evaluation as potential rootstocks. 

S05P30 

Preliminary results on biotization of encapsulated in vitro-derived propagules of ‘Carrizo’ 

citrange (Citrus sinensis × Poncirus trifoliata) 

Germanà M.A. 1 , Micheli M. 2 , Chiancone B. 1 , Bianco C. 3 , Casales F. 1 , and Defez R. 3 

1 Università degli Studi di Palermo, Dipartimento DEMETRA, Italy; 2 Università degli Studi di Perugia, Italy (DSAA), Dipartimento di 

Scienze Agrarie e Ambientali, Italy; and 3 Consiglio Nazionale delle Ricerche (CNR), Istituto di Genetica e Biofisica, Italy. 

mariaantonietta.germana@unipa.it 

The encapsulation technology represents a new tool to integrate micropropagation into the nursery activity. It 

allows combine the advantages of zygotic or gamic seeds with those of micropropagation. The synthetic seed 

or artificial seed, described as “artificially encapsulated somatic embryos, shoots or other tissues which can be 

used for sowing under in vitro or ex vitro conditions”, will be a powerful propagation tool in the nurseryman 

hands, if the levels of the synthetic seeds conversion will be increased also in the nurseries, without the 

asepsis of in vitro laboratories and with the presence of many parasitic microorganisms, like bacteria and fungi, 

responsible for contamination and/or for trophic competition. This research has been carried out in order to 

introduce the biotization to the synthetic seed technology of ‘Carrizo’ citrange (C. sinensis × P. trifoliata), one of 

the most widespread citrus rootstocks, because of its resistance to the Citrus tristeza virus (CTV). With this goal, 

preliminary experiments to set up protocols for biotization, through the introduction of Plant Growth Promoting 

Bacteria (PGPB) into calcium alginate capsules of ‘Carrizo’ citrange in vitro-derived encapsulated microcuttings, 

have been carried out, in order to protect the plantlets from abiotic and biotic factors and to promote their 

growth during the first stages of development. Specifically, the Sinorhizobium meliloti wild type strain 1021 and 

its derivative RD64, that synthesizes 39-fold more IAA as compared to the wild type strain, have been used to 

evaluate their performances in inducing rooting of synthetic seeds. 

S05P31 

Biodegradable films made from PLA-limonene blends for food active packaging applications 

Arrieta M.P. 1 , López J. 1 , Ferrándiz S. 1 , and Peltzer M. 2 

1 Polytechnic University of Valencia (UPV), Technological Institute of Materials, Spain; and 2 University of Alicante (UA), Analytical 

Chemistry, Nutrition and Food Sciences Department, Spain. marrieta@itm.upv.es 

Active packaging films are increasingly being investigated for their application in food packaging industry. Among 

these, an increasing proactive attitude towards a reduction on the environmental impact produced by food 

packaging materials has focused research on bio-based polymers. In this sense, polylactic acid (PLA) films have 

increasingly received attention due to its biodegradation, biocompatibility, overall good mechanical property, 

superior transparency, being obtained from renewable resources, and labeled as Generally Recognized as 

Safe material by the FDA. Packaging has a prominent role in packaged food products, being a key component 

in the food preservation. Since active agents could have an important effect on shelf-life extension of foods, a 

way to develop actives packaging is by adding antioxidants components into the packaging system. Essential 

oil rich in monoterpens contain natural antioxidants and are recognized as food preservatives. Additionally, 

natural antioxidants are of great interest as stabilizers for polymers and the fact that natural antioxidants are 


S05

S05 

biodegradable makes them attractive for use in the stabilization of food packaging. Limonene is present in a 

variety of citrus fruits and is one of most important contributors to citrus flavor. Also, it have been reported 

that limonene shows good antioxidant activity. The aim of this work was to develop biodegradable active 

films made from PLA and limonene blends as an antioxidant compound for food packaging applications. 

Films were prepared and full characterization was carried out by using several techniques and methods. The 

incorporation of limonene in PLA matrix was evaluated and quantified by Pyrolysis Gas Chromatography Mass 

Spectrometry. Flexibility of the films was evaluated by tensile tests. The polymer stabilization was studied by 

the kinetic parameters using thermogravimetric analysis. 

S05P32 

PLA and PLA-PHB incorporated with limonene for biodegraable food packaging 

Arrieta M.P. 1 , López J. 1 , Ferrándiz S. 1 , and Peltzer M. 2 

1 Polytechnic University of Valencia (UPV), Technological Institute of Materials, Spain; and 2 University of Alicante (UA), Analytical 

Chemistry, Nutrition and Food Sciences Department, Spain. marrieta@itm.upv.es 

An increasing environmental concern towards a reduction on the environmental impact produced by plastics 

is contributing to growth the biopolymer industry. Polylactic acid (PLA), polyhydroxybutyrate (PHB) and their 

copolymers are biodegradable materials widely investigated for food packaging applications. One of the 

potential application fields of these materials is as a film. However, amorphous PLA and PHB films are rigid 

and need to be plasticized. The composition of materials in contact with foodstuffs is tightly regulated so food 

grade plasticizers are required. On the other hand, when consumers decide which product to purchase, the 

packaging of a product could influence the decision, therefore transparency in food packaging is required. In 

this sense, essential oil rich in monoterpens, such as limonene, are of great interest as stabilizers for polymers. 

Limonene is one of the most important residues in the citrus industry, so, it would be positive to increase its 

added value from a low-grade by-product to a useful plasticizer. In this work, PLA and PLA-PHB were blended 

with limonene as plasticizers, in a mixer. The films were obtained by compression-moulding at 180°C in a hot 

press. Optical properties using CIELab color space were determined. The influence of plasticization process on 

mechanical properties was determinate by tensile testing according to ASTM-D882 Standard, where average 

percentage elongation at break and elastic modulus were determined. Oxygen transmission rate (OTR) was 

also measured to evaluate the barrier properties of these films to oxygen. 

S05P33 

Shoot tip grafting (STG) in commercial production of disease free, quality-bud grafts of citrus in 

Central India: the present status 


National Research Centre for Citrus (NRCC), Tissue Culture, India. narukullav@gmail.com 

Citrus growers are generally facing a serious problem of decline that is attributed to prevalence of citrus viruses 

and virus like diseases. The average life span of citrus orchards in tropical countries is less than 10 years because 

of these diseases. Hence, the need for healthy certified quality planting stock is recognized as basic to the 

establishment of a viable citrus industry. Use of healthy superior clonal planting material for establishing the new 

orchards will help in controlling the diseases and increasing the productivity. Shoot tip grafting (STG) has been 

proved effective in elimination of diseases and in establishment of healthy citrus orchards worldwide (viz. Brazil, 

USA, Spain, etc.) since decades. Keeping this in view, a comprehensive program based on STG to produce, multiply, 

maintain and distribute the disease free planting stock to citrus growers/nurserymen was initiated nearly 10 years 

ago in Central India. The program named as citrus variety improvement program has the following functions: 1) 

Restricted movement of budwood. 2) Introduction of citrus exotic scion cultivars and cleaning through STG. 3) 

Maintenance of healthy mother trees in protected foundation block under insect proof condition. 4) Continued 

testing and growth quality evaluation. 5) Discarding infected trees. Through successful transfer of STG technology 

from lab to land, so far 2.75 lakhs of certified quality bud grafts of Citrus reticulata cv. ‘Nagpur’ mandarin were 

produced and distributed to citrus growers which facilitated establishment of around 800 hectares of healthy 

citrus orchards in farmer’s fields of Central India, thus paving the way for a sound and sustainable citrus industry. 

In this paper, the authoress will present the detailed role of STG in the citrus improvement program, and the 

procedure and technical requirements for the production of healthy foundation stock. 


Session 06 

FRUIT PHYSIOLOGY 

S06

S06O01 

Effect of male-female interaction and temperature variation in citrus pollen performance 

Distefano G. 1 , Hedhly A. 2 , Las Casas G. 1 , La Malfa S. 1 , Cicala A. 1 , La Rosa G. 1 , Herrero M. 3 , and Gentile A. 1 

1 University of Catania (DISPA), Department of Agriculture and Food Science, Italy; 2 University of Zurich, Institute of Plant Biology, 

Switzerland and 3 Consejo Superior de Investigaciones Científicas (CSIC), Departmento de Pomología, Estación Experimental de Aula 

Dei, Spain. gentilea@unict.it 

Characterizing pollen performance is especially relevant for some economically important genus like Citrus, 

in which failure of the sexual reproductive process resulting in parthenocarpic fruit development and 

seedlessness is a prized character. Pollen-pistil interaction in the three ancestral true-type Citrus species 

was characterized in order to determine the influence of the male and female genotypes, as well as of the 

temperature regime on pollen performance. Specifically, temperature effect on pollen grain germination in 

vitro, and on pollen tube growth either in vivo in cut flowers under controlled temperature chambers or in 

planta under field temperature conditions was characterized. Results obtained showed that temperature 

variation has a strong effect on pollen germination, on pollen tube kinetics, and on their population size 

depending on the specific male-female combination. Furthermore, temperature appears to have an effect on 

the self-incompatibility reaction by affecting the place where pollen tubes are arrested. Overall, our results 

show that pollen performance is not only an inherent characteristic of the pollen genotype, but is largely 

dependent on the particular male-female combination and on genotype-temperature interactions. 

S06O02 

Abscission of reproductive structures in citrus and its control with brassinosteroids and girdling 

Pérez M.C. 1 , Almenares G. 2 , Torres W. 3 , Aranguren M. 2 , Betancourt M. 2 , García M.E. 2 , Núñez M. 3 , Llauger R.E. 4 , 

Mahouachi J. 5 , Iglesias D.J. 6 , and Talón M. 6 

1Instituto Nacional de Ciencias Agrícolas (INCA), Dirección General, Cuba; 2Instituto de Investigaciones en Fruticultura Tropical 

(IIFT), Fisiología, Cuba; 3Instituto Nacional de Ciencias Agrícolas (INCA), Fisiología, Cuba; 4Instituto de Investigaciones en Fruticultura 

Tropical (IIFT), Dirección General, Cuba; 5Instituto Canario de Investigaciones Agrarias (ICIA), España; and 6Instituto Valenciano de 

Investigaciones Agrarias (IVIA), Genómica, España. mcperez@inca.edu.cu 

A study was done to characterize the abscission of reproductive structures under tropical conditions using 

brassinosteroids and girdling for its control. The trial included ‘Valencia Late’ and ‘Washington’ navel orange 

trees. The tendency to abscise was determined since the early stage of flower development until the end of 

fruit-set. Fallen reproductive structures were classified through the BBCH scale, foliar levels of gibberellins 

during fruit-set were also determined and the effect of foliar sprays of analogues of brassinosteroids during 

petal fall and branch girdling from the anthesis until petal fall on fruit-set, foliar gibberellin levels and yield 

were also evaluated. Results indicate that the abscission of reproductive structures was interrupted since 

the beginning by flower development until the end of fruit-set with a maximum during the stage 69 of the 

BBCH scale, when abscission is high and the fall of reproductive structures is increased in initial phenological 

stages, the sink capacity reduces, foliar gibberellin levels rise and vice versa. The spray of the analogue of 

brassinosteroid BB-6 (0.1 mg∙L -1 ) reduced the accumulated abscission in 9% and increased yield in 38%, while 

branch girdling also reduced accumulated abscission and increased yield in 54%. This girdling was preceded 

by a reduction of total carbohydrates and increased gibberellin levels in leaves during the stage II of fruit 

growth and development. 

S06O03 

“To fall or not to fall, that’s the question!” Molecular mechanisms underlying organ abscission in 

citrus 

Tadeo F.R., Agustí J., Merelo P., Estornell L.H., Cercós M., Terol J., Domingo C., and Talón M. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Genómica, España. tadeo_fra@gva.es 

During their life cycle, citrus plants can experience different processes involving separation of cells by 

dissolution of cell adhesion materials and breakdown of cell walls at specific sites on the plant body. Abscission 

enables both vegetative and reproductive organs to be shed in response to developmental, hormonal and 


S06

S06 

environmental cues. From an evolutionary point of view, abscission is a highly favorable process that has 

several advantages such as fruit and seed dispersal as well as the shedding of no longer needed, infected, 

damaged or senescent organs. In an agricultural context, however, abscission is a major limiting factor for 

crop productivity. In this regard, understanding the regulation of abscission is an important item for the citrus 

fruit industry. Deeper understanding on the mechanisms underlying abscission would help to regulate crop 

production and improve current cultural and management practices such as mechanical fruit harvesting or 

removal of undesirable fruit production. In addition, further molecular research on abscission could help to 

elucidate new molecular markers to improve genetic breeding. This review highlights the current status of 

research on genes specifically associated with organ abscission that have been uncovered so far in citrus. 

S06O04 

Carbohydrate control over carotenoid build-up in citrus is conditional on fruit ontogeny 

Fanciullino A.L. 1 , Poiroux-Gonord F. 1 , Poggi I. 1 , and Urban L. 2 

1French National Institute for Agricultural Research (INRA), UR 1103 GEQA, France and 2Université d’Avignon et des Pays du Vaucluse 

(UAPV), Laboratoire de Physiologie des Fruits et Légumes, France. fanciullino@corse.inra.fr 

The final contents of primary and secondary metabolites of the ripe fruit depend on metabolic processes 

which are tightly regulated during fruit ontogeny. Here, we hypothesized that the sensitivity of clementine 

(Citrus clementina) fruit metabolism to carbohydrate supply was conditional on fruit developmental stage. 

Defoliation or temporary shading were used as irreversible and reversible means, respectively, of obtaining 

three levels of fruit load or leaf-to-fruit ratio. Treatments were applied at three key stages of fruit development: 

early after cell division (S1), at color break (S2), and near maturity (S3). The highest fruit load obtained by 

defoliation at S1 had the highest impact on fruit growth, maturity and metabolism, followed by the highest 

fruit load obtained by shading at S1. Soluble sugars decreased by 18% in the first treatment, final fruit size by 

21% and 18% in the irreversible and reversible treatments respectively, while organic acids increased by 46% 

and 29%, respectively. Interestingly, total carotenoids increased by 50% and 18%, respectively. Changes in leaf 

starch content and photosynthesis supported that these early treatments triggered a carbon starvation in the 

young fruits, with irreversible effects. Furthermore, our observations on the early treatments challenge the 

common view that carbohydrate supply influences positively carotenoid accumulation in fruits. We propose 

that early carbon starvation irreversibly promotes carotenoid accumulation. 

S06O05 

Largely altered terpenoids production in red-fleshed fruits of ‘Cara Cara’ navel orange (Citrus 

sinensis L. Osbeck) in comparison with pale-fleshed Seike navel orange 

Xu J., He M., Liu X., Gao H.J., Wang Z., Deng X.X., Cheng Y.J., and Zhang H.Y. 

Key Laboratory of Horticultural Plant Biology, Ministry of Education (HZAU), Postharvest and fruit quality, China. 

xujuan@mail.hzau.edu.cn 

For two growing seasons, the synthesis of carotenoids, limonoids and abscisic acid were investigated in fruits 

of red-fleshed ‘Cara Cara’ and pale-fleshed Seike navel oranges (Citrus sinensis). ‘Cara Cara’ accumulated 

large amount of phytoene, phytofluene, lycopene and thus total carotenoids in its flesh, while β-carotenoids 

were dominant in flesh of ‘Seike’ navel orange. Real time-PCR analysis revealed that lycopene accumulation 

in the juice sacs of ‘Cara Cara’ was more likely attributed to the up-regulated expression of phytoene synthase 

gene than the expression level of lycopene cyclase genes. However, the lack or the decrease of lycopene in 

leaves and fruit flavedo implied the different regulation mechanism in different tissues. In comparison with 

‘Seike’, throughout the fruit development, ‘Cara Cara’ contained lower contents of abscisic acid and higher 

contents of limonin and nomilin in its juice sacs. Additionally, contents of other compounds such as naringin 

(the main bitter flavonoids in the citrus), soluble sugars and organic acids were found significantly different 

between two oranges for both seasons. Furthermore, RNA-seq and bioinformatics’ analysis declared the 

global differences in the processes of carotenoids biosynthesis, starch and sucrose metabolism, citrate cycle 

and glycolysis pathways between the two navel oranges. 


S06O06 

Endogenous factors affecting fruit color development in navel sweet oranges 

Gambetta G. 1 , Gravina A. 1 , Fasiolo C. 1 , Martínez-Fuentes A. 2 , Reig C. 2 , Mesejo C. 2 , Bentancur O. 3 , and Agustí M. 2 

1 Facultad de Agronomía. Universidad de la República (UDELAR), Producción Vegetal, Uruguay; 2 Universidad Politécnica de Valencia 

(UPV), Instituto Agroforestal Mediterráneo, España; and 3 Facultad de Agronomía. Universidad de la República (UDELAR), Biometría, 

Estadística y Computación, Uruguay. cfasiolo@gmail.com 

Fruit colour change is positively associated to endogenous abscisic acid (ABA), soluble carbohydrates (CHOs), 

and negatively related to nitrogenous (N) application, but its endogenous evolution is not clear at all. The 

objective of this work was to study the effect of two growth regulators on fruit colour evolution and on 

the time course of endogenous ABA, CHOs and N concentration in the flavedo of ‘Navelina’, ‘Washington’ 

navel and ‘Navelate’ sweet oranges. Foliar sprays of GA3 (20 mg L -1 ) or norflurazone, an ABA inhibitor (NFZ, 

1 mM), were applied prior to colour break, to adult plants, during two years. In the three cultivars, GA3 

delayed colour break and its final intensity, while NFZ did not affect it. In control fruits, CHOs concentration 

increased during colour development and N (total and proteinaceous fraction) concentration diminished. 

In all experiments, GA3 reduced flavedo CHOs concentration; however, results on N concentration were 

inconsistent. In ‘Navelina’ oranges, GA3 reduced ABA concentration in the flavedo along with colour delay. 

However, in the other two cultivars, flavedo ABA concentration of GA3-treated trees was slightly but not 

significantly lower than control fruit. NFZ did not affect ABA, CHOs or N concentration in the flavedo according 

to colour evolution. Possible roles of these endogenous substances on colour development are discussed. 

S06P01 

Effect of continuously high temperature throughout a growth period on flowering, physiological 

fruit drop and fruit quality in satsuma mandarin 

Sato K.S., Fukamachi H., and Ikoma Y. 

Institute of Fruit Tree Science, National Agriculture and Food Research Organization (NARO), Citrus Research Division, Japan. 

satokei@affrc.go.jp 

In Japan, some reports suggest that annual mean temperature in future (2081-2100) will be 2-3 °C higher 

than that in recent times (1981-2000). However, in satsuma mandarin the influence of continuous high 

temperature throughout a growth period was not well understood though the influence of high temperature 

during short terms (i.e., physiological fruit drop, ripening) has been well studied. Thus, we investigated the 

effect of continuous high temperature from pre-sprouting to fruit maturation on flowering, physiological fruit 

drop and fruit quality in satsuma mandarin. 

Temperature treatment for satsuma mandarin was conducted with a temperature gradient greenhouse 

(TGG) in which two temperature zones were established. One zone was maintained at ambient temperature 

(control). The other zone was maintained at 2°C above ambient temperature (plus 2°C treatment). 

Flowering in plus 2°C treatment occurred earlier than that in control. There was little difference between 

plus 2°C treatment and control in fruit set rate after physiological fruit drop although physiological fruit drop 

occurred earlier in plus 2°C treatment than in control. At optimum harvesting time, color development in plus 

2°C treatment was similar to that in control. However, peel puffing was enhanced in plus 2°C treatment. There 

was little difference in sugar and acid content between plus 2°C treatment and control. These findings suggested 

that the continuous temperature rise of 2 °C might have a bad influence on peel puffing in satsuma madanrin. 

S06P02 

Evaluations of potential fruit abscission and characteristics of seeded and seedless fruit 

abscission in several citrus species during physiological fruit drop 

Kitajima A. 1 , Li X. 2 , Habu T. 1 , Kataoka K. 1 , Nakazaki T. 1 , and Yonemori K. 1 

1 Experimental Farm, Graduate School of Agriculture, Kyoto University (EFGAKU), Experimental Farm, Japan; and 2 Graduate School of 

Agriculture, Kyoto University (GAKU), Plant Production Control Lab., Japan. kitajima@kais.kyoto-u.ac.jp 

We developed an evaluation method for the potential fruit abscission and investigated the characteristics of 

seeded and seedless fruit abscission during secondary fruit drop in several citrus species. 


S06

S06 

The experiment was conducted at 6 weeks after full bloom using satsuma mandarin and tangelo. As an 

evaluation method for the potential fruit abscission, the fruits with peduncle were detached from a tree 

and incubated on 1% agar medium (detached). As a control, the fruits on a tree were treated ringing on the 

peduncle to prevent the translocation of photo-assimilates to the fruit (on tree). The ratios of fruit abscission 

(separation of fruit from disk) at 168 h after treatment in both “detached” and “on tree” were over 70% in 

tangelo and were below 20% in satsuma mandarin. The time course of abscission pattern in “detached” was 

similar to that in “on tree” in both species. The result indicates that the fruit detachment method is useful for 

an evaluation of the potential fruit abscission in citrus. 

The flowers of 7 citrus species were treated with non-pollinated and open-pollinated. These fruits were 

detached and incubated on agar medium at 5 weeks after full bloom. The ratios of fruit abscission at 96 h 

after detachment in both open-pollinated and non-pollinated were over 80% in ‘Ponkan’, navel orange and 

Iyo, and were below 30% in satsuma mandarin, hyuga-natsu and pummelo, respectively. The non-pollinated 

fruits of satsuma mandarin, hyuga-natsu, pummelo were seedless. The results indicate that the potential of 

citrus fruit abscission is different in species and the both of the seeded and seedless fruit abscission potential 

is lower in satsuma mandarin, hyuga-natsu and pummelo. It is suggested that these species would be useful 

for seedless citrus breeding. 

S06P03 

Cross-pollination and control of seed formation in ‘Afourer’ mandarin 

Gravina A. 1 , Gambetta G. 1 , Fasiolo C. 1 , Espino M. 2 , and Rivas F. 3 

1 Facultad de Agronomía. Universidad de la República (UDELAR), Producción Vegetal, Uruguay; 2 URUDOR (URUDOR), Departamento 

Técnico, Uruguay; and 3 Instituto Nacional de Investigación Agropecuaria (INIA), Programa Nacional de Cítricos, Uruguay. agravina@ 

fagro.edu.uy 

‘Afourer’ mandarin, a self-incompatible variety, produce under Uruguayan conditions high number of seeded 

fruits. In order to reduce seed presence, four field experiments were performed, including plant net coverage 

(exp. 1 and 2), and application of different concentrations of copper sulphate and gibberellic acid, one, two 

or three times during the flowering period (exp. 3 and 4). Additionally, artificial pollinations were performed 

with ‘Valencia’ orange and ‘Clemenules’ clementine pollens. Net covered trees had 99% of seedless fruit. In 

experiment one, in two year-old plants, no differences in yield components between open pollination and 

covered plants was registered, but in experiment two, with seven year-old trees, a significant fruit number 

reduction on covered trees was verified. The most efficient treatments to diminish seeds was three applications 

of GA 3 (50 mg L -1 ) alone or combined with CuSO 4 (25 mg L -1 ), that increased seedless fruit from 19 to 31% 

(exp. 3) and from 26% to 52% (exp.4). Additionally, the average number of seeds per fruit decreased from 3.7 

and 2.9 in the controls to 2.3 and 1.8, in experiment three and four respectively. Single flowers self pollinated 

or artificially pollinated with ‘Afourer’ pollen, set similar seedless fruit number. ‘Afourer’ flowers pollinated 

with ‘Valencia’ had the highest percentage of seeded fruit (88%) and seeds per fruit (3), while pollinated with 

‘Clemenules’ clementine only 21% of the fruits had seeds. 

S06P04 

Changes of nutrient element contents and accumulation in fruit of navel orange during fruit 

growth and development 

Peng L.Z., Fa X., Cailun J., Li C., and Lili L. 

Citrus Research Institute of Chinese Academy of Agricultural Sciences,Chongqing (CRICCAAS,CQ), China. penglz809@163.com 

The changes of nutrient element contents and accumulation of N, P, K, Ca, Mg, S, Mn, Zn, Cu, Fe and B in 

fruit of 30 years old ‘Seike’ navel orange (Citrus sinensis) on trifoliate orange (Poncirus trifoliata) rootstock 

were studied. Results showed that: (1) During the fruit development, N, P, Mg, S, Mn and Zn contents in 

fruit reached the highest levels in April, the highest K and Fe contents in July and the highest Ca content 

in October. However B and Cu contents in fruit showed only small changes from April to November. 

With the fruit growing and developing, N, P, K, Mg, S, Zn and B contents in fruit decreased to or near the 


lowest levels at fruit mature stage in November, but Ca and Fe contents in fruit showed their lowest levels 

in young fruit stage from April to June. (2) N, P, K and Cu contents were significantly higher in fruit pulp 

than in fruit peel. Ca, Mn and B contents were significantly lower in fruit pulp than in fruit peel. Mg and S 

contents were very close in fruit pulp and peel. Contents of Zn and Fe were significantly higher in pulp than 

in peel before September but turned into opposite after September. (3) The main period for accumulation 

of N, P, K and Mg in fruit was in June and July. During this period of time in mature fruit, 45.6%, 44.6%, 

53.7% and 57.2% of total N, P, K and Mg were accumulated, respectively. The main accumulation period 

of micro-nutrient elements in fruit was from June to September. (4) At mature stage, there were about 

560mg N or K, 274.9 mg Ca, 42.3-57.3 mg P, Mg or S, and 0.17-3.3mg micro-nutrient elements in each fruit. 

S06P05 

The effects of source-sink ratio on leaf photosynthetic characteristics of ‘Newhall’ navel orange 

Chun C. 1 , Wenwen Z. 2 , Liangzhi P. 3 , Lili L. 1 , Xingzheng F. 1 , Li C. 3 , Xiaohuan M. 2 , Fa X. 2 , Cai L. 2 , and Cailun J. 1 

1 Citrus Research Institute, Southwest University, Chongqing (CRIC,SWU,CQ), China; 2 College of Horticulture and Landscape,Southwest 

University,Chongqing (CHL,SWU,CQ), China; and 3 National Citrus Engineering Research Center,Chongqing, (NCERC,CQ), China. 

chuncpzi@163.com 

Leaf growth and photosynthetic characteristics were measured on 30-year-old ‘Newhall’ navel orange 

(Citrus sinensis) mature leaves on three types of shoots, including no fruit-bearing shoots (NFS), one fruitbearing 

shoots (OFS) and two fruit-bearing shoots (TFS), during fruit development period in 2010. Leaves 

of NFS were larger, thicker, higher relative chl and higher nitrogen (N), phosphorus (P), potassium (K) 

concentration than the leaves of fruit-bearing shoots (FBS). The net photosynthetic rates (Pn) of leaves on 

the top 2nd and 4th nodes on NFS were significantly or very significantly higher than those of the same 

position leaves on FBS, as well as the average Pn of the 2nd, 4th and 6th leaves (except for on 150th day 

after full bloom). As to the leaf Pn of the two types of FBS, the OFS was slightly higher, and the significant 

difference of the average Pn of the 3 position leaves between the two types of FBS occurred on 130th day 

after full bloom. With the fruits bearing increased on a shoot, the leaf thickness, leaf area, leaf N level, 

leaf P level, leaf K level, relative chl content and average leaf stomatal conductance (Gs) decreased along 

with the intercellular CO 2 concentration (Ci) and transpiration rate (E) increasing. For all the 3 types of 

shoots, as the position of the leaves on a shoot located lower, the leaf N, P and K level increased. For the 

area, thickness, relative chl content and Pn of leaves located on different shoot positions. Fruits from the 

OFS were larger with thicker peel, significantly higher Vc content than fruits from the TFS. Therefore, the 

relatively poor differentiation and development of leaves on FBS resulted in their lower Pn. Compared with 

the leaf differentiation and development, source-sink ratio had slighter effects on leaf Pn. 

S06P06 

Anatomy of abnormal ‘HB’ pummelo caused by boron deficiency 

Li S. 1 , Liu Y.Z. 1 , Yang C.Q. 1 , and Peng S.A. 1 

1Key Laboratory of Horticultural Plant Biology (KLHPB), Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, P. 

R. China. ganjuli_2002@mail.hzau.edu.cn 

Boron (B) deficiency is a worldwide nutritional disorder in citrus industry. Under B deficient condition, 

symptoms of corky split veins in mature orange leaves, weak tree vigor and low yield are always visible. 

Moreover, B deficiency could reduce fruit size (shrunk fruit) and increase fruit peel thickness. In this study, we 

used paraffin section technique to investigate the anatomic structure of mature-fruit albedo between normal 

and B deficient fruits, by using ‘HB’ pummelo (Citrus grandis) as research material. As compared with in the 

normal fruit, the spongy cells arranged compactly and the average number of vascular bundle per eyeshot 

increased in the albedo of B deficient fruit. Moreover, vascular bundles could be found to be linked and the 

trachea density or trachea number in vascular bundle was obviously increased in the spongy tissue of the 

abnormal fruit. In addition, we also isolated vessel elements from the spongy tissue and compared their 

difference between the normal and abnormal (B deficient) fruits. In general, normal vessel elements from 

spongy tissue are plump. However in the spongy tissue of B deficient fruits, they deformed with hyperplasia 

and uneven vessel wall; moreover, much perforation could be found in the vessel side wall and the number of 

pitted vessel increased while the numbers of scalariform and reticulated vessels decreased. 


S06

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S06P07 

Pre-harvest rind breakdown in New Zealand and a comparison with similar problems reported 

from other countries 

Pyle K.R. 

Pyle Orchards and Consulting Pty Ltd, New Zealand. kpyle@xtra.co.nz 

Pre-harvest rind breakdown is an occasional problem on mandarins, tangelos and oranges in New Zealand. 

It usually affects fruit at or soon after colour break and is often referred to as ‘on-tree oleocellosis’. It is 

normally associated with extreme wet, cold weather events and with gusty winds. In the Gisborne region 

in July 2011, some exposed, wet orchards, mainly navel oranges, were adversely affected with up to 50% 

fruit marking and 60% fruit drop in the worst cases.This prompted a more detailed examination of the 

condition, a review of the local meteorological and other factors that may have caused the breakdown and 

some recommendations for growers. These are described, together with a brief comparison of similar preharvest 

rind defects and their management obtained from international literature and correspondence. 

The condition most closely resembles pitting of ‘Pineapple’ orange described in Florida, pitting of ‘Fortune’ 

mandarin reported in Spain, rind staining of navels and tangelos in Morocco, mandarin rind disorder in 

California, rind spotting of clementines in Greece and ‘pateta de rata’ or ‘colapso de la corteza’ on ‘Navelate’ 

in Spain and Chile. 

S06P08 

The effect of combined spraying of gibberellin and prohydrojasmon on peel puffing in satsuma 

mandarin 

Ikoma Y., Matsumoto H.M., and Sato K.S. 

NARO Institute of Fruit Tree Science (NIFTS), Citrus Research Division, Japan. yoshino@affrc.go.jp 

Peel puffing of satsuma mandarin is a serious physiological disorder in which the pericarp and flesh separate. 

This disorder causes increased fruit rot and decreases eating quality. Because peel puffing is promoted by 

high temperatures and humidity, there is a fear that global warming will cause frequent occurrence of peel 

puffing. To reduce peel puffing effectively, combined spraying of the plant hormones gibberellin (GA) and 

prohydrojasmon (PDJ) was examined. In the present study, 3 chemical sprays (1 mg∙L -1 GA spray, 1 mg∙L -1 

GA plus 25 mg∙L -1 PDJ spray and 1 mg∙L -1 GA plus 50 mg∙L -1 PDJ spray) were prepared just before treatment. 

On August 29, the selected branches of satsuma mandarin trees were treated with these chemical sprays, 

respectively. At optimum harvesting time, fruit qualities were investigated. Peel puffing was significantly 

inhibited by combined spraying of GA and PDJ but not by spraying of GA without PDJ. There was no difference 

between two combined sprays (1 mg∙L -1 GA plus 25 mg∙L -1 PDJ spray and 1 mg∙L -1 GA plus 50 mg∙L -1 PDJ 

spray) in the intensity of the peel puffing inhibition. Coloring was delayed by combined spraying of GA and 

PDJ but not by spraying of GA without PDJ. The intensity of the delay of coloring was smaller in 1 mg∙L -1 Ga 

plus 25 mg∙L -1 PDJ spray than in 1 mg∙L -1 GA plus 50 mg∙L -1 PDJ spray. In TSS, there was no difference among 

treatments. In contrast, citric acid content became high by combined spraying of GA and PDJ. Especially 

in 1 mg∙L -1 GA plus 50 mg∙L -1 PDJ spray, the increase in citric acid content was remarkable. These results 

suggested that the optimum concentrations of GA and PDJ for inhibition of peel puffing were 1 and 25 mg∙L -1 , 

respectively. 

S06P09 

Production cost reduction of Shiranuhi mandarin hybrid in plastic house cultivation using 

underground air and air mixer. 

Han S.H. 

Jeju National University (JNU), Horticulture, Korea, Republic. sangheon@jejunu.ac.kr 

The Jeju citrus area is located in a cold area, but cultivation is generalized using plastic film houses. 

The late maturing mandarin variety ‘Shiranuhi’ started to be grown in 1990 and it has reached 1,188 ha 


(5.6% of the total citrus area) with a production of 22.000 tons, that represent 3.7% of the whole citrus 

production. The fruit price of this variety is high compared with imported citrus, as a consequence of 

FTA recent reduction of customs duties, and domestic consumption is decreasing, and thus, production 

cost reduction is needed. This research attempted production cost reduction using underground aerial 

use and an air mixer in plastic film house cultivation. The system maintained a similar temperature than 

conventional systems that use a heavy oil hot air during the winter period, but CO 2 content was about 5 

times higher and the size of the fruit was better. The fruit quality was similar in the two houses. After the 

annual production cost was compared, the underground aerial use house could reduce the production 

cost about 50 %. We expect to utilize such production cost reduction technique and to be able to compete 

with imported citrus. 

S06P10 

Abscission study during citrus fruit maturation in Corsica: unfavorable environmental conditions 

for fruit shedding 

Khefifi H. 1 , Ben Mimoun M. 2 , Luro F. 3 , and Morillon R. 4 

1Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD)/Institut National de la Recherche 

Agronomique (INRA)/ Institut National Agronomique de la Tunisie (INAT) (CIRAD/INRA/INAT), France/Tunisia; 2Institut National 

Agronomique de Tunisie (INAT), Production végétale, Tunisia ; 3Institut National de la Recherche Agronomique (INRA), Génétique et 

Ecophysiologie des Agrumes, France; and 4Centre de Coopération Internationale en Recherche Agronomique pour le Développement 

(CIRAD), Amélioration des plantes à multiplication végétative, France. khefifihajer@yahoo.fr 

Citrus fruit development and ripening are complex processes involving physiological and biochemical 

changes that are under hormonal, nutritional and environmental control. One of the most evident 

phenomena in late maturation is shedding of ripe fruit. A previous study on sweet orange abscission 

supposed that fruit shedding was related to the increase of sugars content of pulp juice. To investigate 

this potential relationship between fruit abscission and internal maturity parameters we investigated the 

fruit maturity process of 10 mandarin x clementine hybrids and 9 commercial sweet orange varieties with 

different maturity time. Morphological and biochemical analyses (acidity, total soluble solids, fruit weight 

thickness of the flavedo, thickness of the peduncle and external color) were carried out on fruit sets of 

the different varieties during the maturation process, from December to June. The abscission initiation 

was evaluated by measuring the force required to detach the fruit of the peduncle. Analysis showed that 

under our local conditions, abscission was generally not expressed even though fruit maturation was 

evolving. Therefore, we suppose that even though the local conditions have an important effect, abscission 

of citrus fruit also results from environmental-genotype interactions. Moreover, evolution of abscission 

and fruit parameters are not correlated, suggesting the independence in the processing of maturation and 

abscission. 

S06P11 

Fruit quality characteristics of very early satsuma mandarin by soil mulching with poly porous 

reflective sheet 

Han S.G., Kim Y.H., and Moon Y.E. 

Citrus Research Station, National Institute of Horticultural and Herbal Science, RDA. skhan@korea.kr 

This experiment was carried out to determine the effect of soil mulching with a porous water-proof sheet 

(PWPS) on fruit quality of the very early maturing satsuma ‘Nichinan I go’ at citrus orchards in Jungmun, 

Seogwipo, Jeju, Korea. Soil was mulched with a porous water-proof sheet on early June and started irrigation 

when the fruits reached 8.5oBrix. At maturity, soluble solid content was12.8º Brix in the mulching plot 

and 10.2º Brix in the control, showing a significant increase of mulching of 2.6o Brix . Acidity in fruits of 

the mulching plot was slightly lower than in the control plot. Peel coloration (Hunter parameters) also was 

significantly higher in the mulching plot than in the control. 


S06

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S06P12 

Fruit growth and sugar and acid characteristics in leafy and leafless fruits of satsuma mandarin 

Kim S.B. 1 , Oh E.U. 1 , Yun S.H. 2 , Oh H.W. 3 , and Song K.J. 1 

1 Jeju National University (JNU), Faculty of Bioscience and Industry, Republic of Korea; 2 National Institue of Horticultural and Herbal 

Science (NHHS), Citrus Research Station, Republic of Korea; and 3 Jeju Special Self-governing Province Agricultural Research & Extension 

Services (JSSPARES), Citrus Breeding Center, Republic of Korea. kwansong@jejunu.ac.kr 

The study was conducted to investigate the possible differences of fruit bearing type in satsuma mandarin, with 

leafy (LY) and leafless (LS) fruits, on fruit growth and sugar and acid content. Fruit growth including fruit length, 

diameter, shape index (diameter/length), weight, and size distribution was not different between LY and LS 

fruits at ripening time. Total soluble solids (TSS) of fruit juice increased and acidity decreased continuously and 

then TSS: acidity ratio increased with fruit development from 100 days after anthesis (DAA) to ripening time. 

Soluble sugar was continuously increased, whereas organic acid decreased. Theses tendencies were related to 

increase of sucrose and decline of citric acid, respectively. However, there was no effect of fruit bearing type on 

TSS, acidity, and TSS: acidity ratio, and soluble sugar and organic acid composition. Also, photosynthetic rate and 

chlorophyll index with SPAD value were not different between leaves adjacent to LY and LS fruits. The results 

indicate fruit bearing type in satsuma mandarin do not affect fruit growth, and sugar and acid content. 

S06P13 

Physiological investigation of June drop in Thomson navel orange (Citrus sinensis) in the north of Iran 

Akhlaghi Amiri N. 1 , Asadi Kangarshahi A. 2 , and Arzani K. 3 

1 Mazandaran Agricultural and Natural Resources Research Center, Seed and Plant Improvement, Iran; 2 Mazandaran Agricultural and 

Natural Resources Research Center, Soil and Water, Iran; and 3 Tarbiat Modares University (TMU), Horticultural Science, Iran. 

neginakhlaghi@yahoo.com 

One of the reasons for high losses in some varieties of citrus like ‘Thomson’ navel orange is summer 

physiological drop. Recognition of physiological events in the fruit abscission zone and application of some 

nutritional treatments can reduce or control abscission, so affect on decreasing losses. This experiment was 

conducted to investigate auxin, cellulase and poly-galacturonase content in the abscission zone of ‘Thomson’ 

navel orange and its relationship with fruit abscission percent. The experiment was performed in a randomized 

complete block design with 8 treatments: 1.Control; 2.Urea (1%); 3. Urea 2,4-D (15 mg L -1 ); 4.Urea GA3 (15 

mg L -1 ); 5.Urea Sucrose (1%); 6.Urea ZnSO 4 (0.5%); 7.Urea ZnSO 4 2,4-D and 8.Urea ZnSO 4 GA3, with four 

replications. Foliar application was done in late May. Results showed that auxin level in treatments 5, which 

included sucrose in its composition, was the highest among all treatments. This treatment also provided 

the lowest amount of hydrolytic enzymes. Decreasing cellulase and poly-galacturonase activity also reduced 

fruitlet abscission in treatment 5. Reduced fruitlet competition for carbohydrates could be the main reason 

explaining the reaction of trees to this treatment. 

S06P14 

Reducing alternate bearing index in satsuma mandarin by nitrogen management and pruning in 

north of Iran 

Asadi Kangarshahi A. 1 , Akhlaghi Amiri N. 2 , and Savaghebi Gh.R. 3 

1 Mazandaran Agricultural and Natural Resoueces Research Center, Soil Science, Iran; 2 Mazandaran Agricultural and Natural Resoueces 

Research Center, Seed and Plant Improvement, Iran; and 3 Tehran University (TU), Soil Science, Iran. kangarshahi@gmail.com 

In order to reducing alternate bearing in satsuma mandarin (Citrus unshiu), an experiment was conducted 

in randomized complete block design with 5 replications and 6 treatments during 4 years. Treatments 

include: 1. Control; 2. Autumn nitrogen application (in on years based on leaf analysis and yield); 3. Spring 

pruning (in on years); 4. Summer urea sprays (4 g L -1 in on years); 5. Winter urea spraying (10 g L -1 after 

on years); 6. Urea spraying with autumn nitrogen using and spring pruning. To obtain alternate bearing 

index, the ratio of yield difference in each two consecutive years to total yield of the same two years in 

each treatments was calculated then the average of all was taken. Results showed that in all treatments, 

alternate bearing cycle was reduced compared to control trees. But in treatment 6, alternate bearing cycle 


almost disappeared and total yield in four years reached to an acceptable level. Also index of alternate 

bearing was calculated for all treatments and results showed that treatment 6 had the lowest and control 

had the highest index among other treatments. So, as in treatment 6 (urea spraying with autumn nitrogen 

application and spring pruning), alternate bearing almost was balanced and total yield increased and in 

each year reached to an acceptable amount. Use of this treatment in citrus plantings in north of Iran could 

be economical and profitable. 

S06P15 

Possibility of adjusting alternate bearing cycle in satsuma mandarin (Citrus unshiu) in north of Iran 

Asadi Kangarshahi A. 1 and Akhlaghi Amiri N. 2 

1 Mazandaran Agricultural and Natural Resources Research Center, Soil Science, Iran; and 2 Mazandaran Agricultural and Natural 

Resources Research Center, Seed and Plant Breeding, Iran. kangarshahi@gmail.com 

Alternate bearing is one major problem in some citrus varieties like satsuma mandarin. An alternate 

bear tree does not produce a regular crop in consequence years. Reduced fruit quality in “on year” and 

decreased quantity in “off year” cause economic loss to producer. To evaluate possibility of reducing this 

disorder, an experiment was conducted in randomize complete block design with 5 treatments: 1. Control; 

2. Optimum using of chemical fertilizers (based on leaf analysis and annual yield prediction); 3. Optimum 

using of chemical fertilizers and NAA spraying (300 mg L -1 during June drop in on years); 4. Optimum using 

of chemical fertilizer and 2,4-D spraying (50 mg L -1 during June drop in on years) and 5. Optimum using of 

chemical fertilizer and sucrose spraying with 4 replications in 4 consecutive years on satsuma mandarin 

mature trees. Control trees had the most alternate bearing during 4 years, as showed one “on” year, two 

consecutive “off” years and one “on” year, respectively. On the other hand, other 4 treatments reduced 

number of “off” years to one, during 4 years. Treatment 2 had the highest yield in “off” year and the 

lowest yield in “on” year. The smallest and lightest fruit in first, second and fourth years was allocate to 

control. During 4 years, the lowest total yield was recorded in control plants. In conclusion, treatment 2 

by reducing yield in “on” year, increasing yield in “off” year and reduce number of “off” years compare to 

control and treatments 3, 4 and 5 by reducing number of “off” years and increasing fruit size in on years 

caused adjusting alternate bearing cycle, increase total yield in consecutive years, decrease fruit losses and 

improve marketability in satsuma mandarin. 

S06P16 

Reproductive behavior of plants of ‘Valencia’ sweet orange under two soil moisture conditions 

Laskowski L.L. 

Universidad Lisandro Alvarado (UCLA), Agronomía - Cs. Biológicas, Venezuela. llaskowski@ucla.edu.ve 

Drought in the tropics impose cessation of reproductive growth in citrus. In Venezuela has been established a 

minimum requirements of 1200 mm of precipitation per year to maintain a profitable citrus farm. Otherwise, 

irrigation is absolutely necessary to sustain productivity. During this investigation we evaluated the fruit 

set, growth and fruit quality in plants of ‘Valencia’ sweet orange (Citrus sinensis) subject to the application 

of deficient irrigation. Plants of 8 years of experimental orchard at the University Lisandro Alvarado, Lara, 

Venezuela, were used. Starting from the first sprouting induced by the rains applied two irrigation treatments: 

50 and 100% of the water requirement, considering the losses by evapotranspiration. In each plant were 

selected four branches of 30 nodes and each month we proceeded to determine: number of flowers, fruit 

number and diameter. After reaching fruit maturity, we took between 20 and 15 fruits of each plant to 

determine: fresh mass, skin thickness, volume of juice, ° Brix, TSS and juice acidity. As a result, the fruits of 

plants under 100% irrigation during the first 11 daa increased growth rate and shown higher percentage of 

abscission compared to 50% irrigation. Next, until the end of study (244 daa), fruit set, fruit diameter and 

quality were similar in both treatments and were comparable to reported for variety. The quality of the juice 

shown to be significantly more palatable under deficient irrigation. In conclusion, the 50% decrease in the 

amount of irrigation water considering the weekly evaporation losses did not affect plant productivity and 

fruit quality under the environmental conditions studied. 


S06

Session 07 

REGULATION OF GROWTH 

AND DEVOLOPMENT 

S07

S07O01 

Citrus developmental research: a historic, conceptual perspective 

Goldschmidt E.E. 

The Hebrew University of Jerusalem, The Robert H. Smith Faculty of Agriculture, Food and Environment, Israel. 

goldsmit@agri.huji.ac.il 

As long as microscopes were the major research tool, developmental anatomy and morphology led 

the way. But then, towards the middle of the 20th century, horticulturists were enchanted by the plant 

hormone concept. The hormonal thinking dominated citrus developmental physiology for a long time; 

flowering, fruit development and ripening, abscission, rooting and vegetative growth were all attributed 

to one, specific plant hormone or to the perplexing ‘hormonal balance’ concept. The synthetic growth 

regulators were exploited in every possible way to solve all practical problems. A major representative of 

this ‘Hormonal’ era was the renown Israeli citrus researcher S.P. Monselise (1920-1986). The emergence 

of the source-sink concept (ca. 1980) partially replaced the hormonal hypothesis. The source-sink 

hypothesis claims that carbohydrate levels control the major stages of the fruiting process –flowering, fruit 

set and fruit enlargement– and are, therefore, responsible also for the ‘alternate bearing’ phenomenon. 

Although the effects of girdling and fruit thinning seem to support the sink-source concept, direct control 

of flowering and fruit set by carbohydrate levels was not unequivocally demonstrated. The Spanish 

researcher J.L. Guardiola (1943-2010) played a major role in this debate. But then, rather soon, came 

the molecular-genetic era, forcing us all to acquire a new language and follow its logic. Citrus research is 

still a few steps behind Arabidopsis but, here we are, still doing our best in order to solve the remaining 

mysteries of citrus. 

S07O02 

Stock-scion interactions in grafted citrus: a role for microRNA 

Tzarfati R. 1 , Ben-Dor S. 2 , Sela I. 1 , and Goldschmidt E.E. 1 

1 The Hebrew University of Jerusalem, Institute of Plant Science and Genetics in Agriculture, Israel; and 2 The Weizmann Institute, 

Biological Services, Israel. goldsmit@agri.huji.ac.il 

Grafting is a widely used plant propagation technique in horticultural crops, but the physiological basis 

of stock-scion interactions is as yet, incompletely understood. Recent studies indicate that movement of 

proteins and small RNAs through the graft union might be involved. MicroRNAs (miRNAs) are known to 

play a significant role in regulation of higher plants’ developmental and metabolic traits. We would like 

to hypothesize that changes in expression of mRNAs play a role in mediating the effects of grafting. The 

objective of the present study was to examine this hypothesis in citrus. We have determined the expression 

of a broad range of mRNAs in citrus leaf petioles, as affected by grafting. Four stock/scion combinations 

(‘Merav’ mandarin and ‘Star Ruby’ grapefruit scions X ‘Troyer’ and ‘Volkamer’ rootstocks), rootstock autografts 

and non-grafted rootstock controls were examined. Microarray comparisons of mRNA expression 

revealed significant differences in major as well as minor mRNAs. Grafting caused a dramatic reduction 

in the expression of the major miR156 (and miR157) which appear to be associated with reduction of 

juvenility in woody plants. Expression of miR894 also declined after grafting. Differential rootstock and 

scion-dependent expression of the minor miR397 was found in petioles of grafted scions, while in nongrafted 

rootstocks, the expression of miR397 was barely detectable. Bioinformatic analysis confirmed the 

presence of miR397 in the citrus genome, validated its sequence and demonstrated its ability to form 

a stem loop. The differences in miR397 expression might be related to copper and other micronutrient 

requirements of citrus stock-scion combinations. Thus, our results support the hypothesis, suggesting an 

involvement of specific mRNAs in engendering physiological effects of grafting. The precise mechanism 

remains to be elucidated. 

Supported by funds of the Israeli Citrus Marketing Board. 


S07

S07 

S07O03 

Alternate bearing in Citrus reticulata - An overview 

Verreynne J.S. 1 , Faber B.A. 2 , and Lovatt C.J. 3 

1 Nulandis (Nulandis), South Africa; 2 University of California Cooperative Extension (UCCE), Ventrua and Santa Barbara Counties, 

United States of America; and 3 University of California-Riverside (UCR), Department of Botany and Plant Sciences, United States of 

America. carol.lovatt@ucr.edu 

Alternate bearing, cycling of heavy on-crops with light off-crops, reduces mandarin (Citrus reticulata) grower 

income. On-trees produce numerous small fruit of reduced commercial value; Off-trees produce too few fruit 

for a good income. The on-crop causes correlative inhibition (auxin>cytokinin) of buds that produce summer/ 

fall vegetative shoots, reducing the number of nodes that bear inflorescences at bloom, and also inhibits spring 

bud break. The effect of crop load on return bloom is strongest on bearing shoots on on-crop trees compared 

to nonbearing shoots on on-crop trees and nonbearing shoots on off-crop trees, which are least affected. Thus, 

return yield is a function of the number of nonbearing shoots per tree. Trunk injecting (to avoid the problem of 

poor leaf uptake) of on-crop ‘Clemenules’ clementine trees with an auxin-transport inhibitor and/or a cytokinin 

in July and again in January, mitigated the effects of the on-crop on summer/fall shoot growth and spring bud 

break and successfully increased return bloom. One treatment tested significantly increased return yield relative 

to untreated on-crop (Year 1) control trees and equal to that of untreated off-crop (Year 1) control trees. Our 

goal is to develop a cost-effective strategy that mitigates the effect of the on-crop and increases ‘Clemenules’ 

clementine 2-year cumulative total yield, yield of commercially valuable large fruit and grower net income. 

S07O04 

Relationship between a citrus FLOWERING LOCUS T expression and fruit bearing 

Nishikawa F. 1 , Iwasaki M. 1 , Fukamachi H. 1 , and Endo T. 2 

1 National Agriculture and Food Research Organization, Institute of Fruit Tree Science (NIFTS), Kuchinotsu Citrus Research Station, 

Japan and 2 National Agriculture and Food Research Organization, Institute of Fruit Tree Science (NIFTS), Okitsu Citrus Research 

station, Japan. fumien@affrc.go.jp 

Citrus trees often show alternate bearing where a high yielding ON year is followed by a low yielding OFF 

year. This behavior results from a suppression of subsequent flowering by high fruit bearing. In this study, we 

investigated whether a flowering-related gene, citrus FLOWERING LOCUS T (CiFT) is related to the suppression 

of flowering by fruit bearing. In satsuma mandarin trees with different amounts of fruit, CiFT expression in 

November, which is the period of floral induction, was negatively and highly correlated with the fruit weight 

per leaf area ratio at harvest (R=-0.857, p

S07O06 

Exploring microRNA target modulation in citrus somatic embryogenesis by high-throughput 

small RNA and degradome sequencing 

Wu X.M., Liu M.Y., Xu Q., Deng X.X., and Guo W.W. 

Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University (HZAU), China. 

ema@webmail.hzau.edu.cn 

Somatic embryogenesis (SE) from callus is an important approach of in vitro regeneration, as well as a model 

for studying mechanisms of nucellar polyembryony in citrus. In our study, small RNA (sRNA) and degradome 

(the collection of molecules that result from the incomplete degradation of mature, functional RNAs) 

sequencing were implemented on embryogenic callus (EC) and non-embryogenic callus (NEC) of ‘Valencia’ 

sweet orange, as well as on EC cultured on glycerol medium for 1-4 weeks (E1-4) on which somatic embryos 

were induced. A total of 64 previously known and 191 novel microRNAs (miRNAs) were identified. Quite 

a few miRNAs were found to be highly expressed in NEC, while only 25 miRNAs were more abundant in 

embryogenic tissues than in NEC. miRNA expression was detected in preserved callus of seven citrus varieties 

with different SE capability. Five miRNAs, miR156, 164, 390, 171 and 059, were found to be expressed higher 

in callus with SE capability compared to callus that had lost SE capability. In addition, 1,150 transcripts were 

identified to be cleaved by 129 miRNAs in the three tissues (EC, NEC, E1-4). A total of 347 phased siRNA 

(phasiRNA) were identified and most highly expressed in NEC and only two expressed higher in EC or E1-4 

tissue than in NEC. For the over-accumulation of one of the most conserved miRNAs, miR156 in EC and 

SE processes of ‘Valencia’, the Csi-MIR156 gene was overexpressed by a 35S promoter in ‘Guoqing No. 1’ 

satsuma mandarin (Citrus unshiu), which had lost SE capability over years. Although the SE capability was not 

recovered, the overexpression lines tended to accumulate significantly more amyloids, which resembled EC 

cells of ‘Valencia’ with strong SE capability. 

S07P01 

Periods of normal and induced vegetative and reproductive shoots of ‘Persian’ lime (Citrus latifolia) 

Medina-Urrutia V.M. 1 , Durán-Martínez C.M. 2 , Virgen-Calleros G. 2 , Robles-González M.M. 2 , and Rendon-Salcido L.A. 2 

1Universidad de Guadalajara (CUCBA-UDG), Centro Universitario de Ciencias Biológicas y Agropecuarias, México; and 2Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias (INIFAP-Colima), CIRPAC, México. vmmedinau@gmail.com 

‘Persian’ lime fruit is mainly produced under tropical conditions in the State of Veracruz in México. As the 

demand in international markets has increased, new lime orchards also were established in subtropical 

regions. Information about the phenological performance of ‘Persian’ lime trees under this climate is 

scarce. The objective of this work was to determine the time of vegetative (VEG) and reproductive (REP) 

sprouting of ‘Persian’ lime trees under subtropical conditions of Jalisco State in México. Two orchards 

of lime trees budded on ‘Volkamer’ lemon (C. volkameriana) rootstock and planted on clay soils were 

selected. The first site was located at San Martin Hidalgo (SMH) at 1518 m of altitude, mean temperature 

of 16.7 to 24.4 °C and average annual rainfall of 908 mm. The second orchard was planted in Atotonilco 

(ATO) at 1606 m of altitude, mean temperature of 15.7 to 22.6 °C and with 856 mm of rainfall. Tree age was 

six- and four-years-old at SMH and ATO respectively. VEG and REP shoots were recorded biweekly during 

two years. Results showed that periods of VEG and REP shoots were very similar in both regions. Two peaks 

of VEG shoots were detected, one initiated in middle winter (February) and the second in middle summer 

(end of June-beginning of July). The production of VEG shoots during the summer season was 3 fold greater 

than the winter sprouting. VEG sprouting extended 15-40 days more during winter than in the summer 

season. Both mixed and REP shoots were also produced in a higher proportion during summer than in the 

winter season. VEG and REP shoots emerged in summer time were induced by a treatment of water stress 

applied before the initial rainy season. Normal REP and VEG shoots emerged during winter were associated 

with lower night temperatures (6 to 13 °C) and higher day temperatures (24 to 29 °C) recorded during this 

period. Fruits initiated in the summer bloom required 130-145 day to harvest. Flowering during winter 

time preceded harvest by more than 150 days. 


S07

S07 

S07P02 

Daily temperature amplitude affects the vegetative growth and carbon metabolism of orange 

trees in a rootstock-dependent manner 

Bueno A.C.R., Prudente D.A., Machado E.C., and Ribeiro R.V. 

Instituto Agronomico (IAC), Laboratorio de Fisiologia Vegetal Coaracy M Franco, Brazil. rafael@iac.sp.gov.br 

Both instantaneous and average growth temperatures affect plant metabolism, and the physiological 

importance of daily variations in temperature is frequently underestimated. In this study, we hypothesized 

that vegetative growth would be stimulated in orange trees subjected to large daily temperature variations 

even without changes in the average daily air temperature or the amount of energy. This hypothesis was tested 

with orange trees grafted onto ‘Rangpur’ lime or ‘Swingle’ citrumelo rootstocks and grown for 20 days under 

day/night thermal regimes of 25/25 ºC or 32.5/17.5 ºC. Such regimes imposed daily temperature variations 

of 0 ºC and 15 ºC. Plant growth, photosynthesis, respiration and carbohydrate availability in leaves, stems and 

roots were measured under both thermal conditions. The daily temperature variation affected the carbon 

metabolism of young citrus trees; plants grown with 15 ºC of daily variation used more of the carbon stored in 

mature leaves and roots and the energy generated by respiration for the biosynthesis of vegetative structures, 

such as leaves and branches. Thus, there was a significant increase in the leaf area of plants subjected to the 

high daily temperature variation. Current photosynthesis was similar in the two thermal regimes; however, 

the photosynthetic rates increased under the 15 ºC variation when measurements were normalized to 25 ºC. 

In addition to the stimulatory effect of the source-sink relationship on photosynthesis, we suggest a probable 

involvement of hormonal regulation of plant growth through gibberellin metabolism. The rootstock affected 

the response of the canopy to daily temperature amplitude, with the Rangpur lime improving plant growth 

through higher carbohydrate availability in roots. This is the first report that highlights the importance of daily 

temperature variations for citrus growth and physiology under non-limiting conditions. 

S07P03 

The effects of paclobutrazol and fruit on flowering and carbohydrate accumulation in roots, 

branches and leaves of alternate bearing clementine mandarin 

Martínez-Fuentes A. 1 , Mesejo C. 1 , Muñoz-Fambuena N. 1 , Reig C. 1 , González-Mas M.C. 2 , Iglesias D.J. 2 , Primo-Millo E. 2 , 

and Agustí M. 2 

1 Instituto Agroforestal Mediterraneo. Universitat Politècnica de València (IAM-UPV), España; and 2 Instituto Valenciano de 

Investigaciones Agrarias (IVIA), Citricultura y Producción Vegetal, España. carmeco@upv.es 

This study aimed to determine the effects of paclobutrazol (PCB) in on- and off-bearing trees on flowering and 

carbohydrate accumulation in roots, branches and leaves of ‘Hernandina’ clementine mandarin. Application 

of PCB (1 g tree -1 ) to the roots during the flower bud induction period (November) significantly increased bud 

sprouting and flowering in off-trees. However, this effect was prevented in on-trees. One month before the 

treatment with PCB, hexose concentrations were significantly reduced in roots from both on- and off-trees 

compared to untreated trees, but sucrose concentration was only reduced in on-trees. At the moment of 

bud sprouting, sugar concentrations significantly increased in leaves from all treatments. PCB significantly 

increased hexose concentrations in leaves from on-trees compared to untreated trees. On the other 

hand, sucrose concentration was significantly higher in leaves from off-trees. No significant differences in 

carbohydrate concentrations were found in branches. Neither carbohydrate contents in roots nor in leaves 

and branches due to PCB treatment or fruit was related to flowering intensity. 

S07P04 

Fruit set in orange with phytohormones and its relation to engogeneous levels of GA 3 

Galván J.J. 1 , Martínez A. 1 , López N. 1 , and Salazar O. 2 

1 UAAAN (UA), Horticultura, México; and 2 Universidad Autónoma de Tamaulipas (UAT), UAMAC, México. juan.galvan@uaaan.mx, 

doctorgalvanluna@hotmail.com 

This research work aims to contribute to increasing the fruit set given the importance fruit set has in determining 

the harvest. This work evaluated the effects of phytohormones (auxins, gibberellins and cytokinins) in fruit 


set of the orange varieties ‘Washington’ navel and ‘Thomson’ (Citrus sinensis).The design was a split plot in a 

randomized complete block with five treatments and four replications. Flowering tissue samples were stored 

in liquid N until the extraction of gibberellins and the identification and quantification of GA3. The results 

show statistically significant differences (P ≤ 0.05) between treatments in the number of fruits retained on the 

129 d after flowering and the percentage of final set. GA3 content ranged from 1.66 mg g -1 in the control to 

20.79 mg g -1 dry weight in the high dose. The mean doses of 32.2 mg L -1 of auxins, 32.2 mg L -1 of gibberellins 

and 83.2 mg L -1 of cytokinins, resulted in the largest increases in fruit set. 

S07P05 

Analysis of expressed proteins in the pollen tube occuring in the self-incompatible response 

using mass- or single-culture system of mature pollen in citrus. 

Abe A. 1 , Uchida A. 2 , Hoshino Y. 3 , Sakakibara Y. 1 , Suiko M. 1 , and Kunitake H. 1 

1 University of Miyazaki (UOM), The Graduate School of Agriculture, Japan; 2 University of Miyazaki (UOM), The Interdisciplinary 

Graduate School of Agriculture and Engineering, Japan; and 3 Hokkaido University (HU), Field Science Center for Northern Biosphere, 

Japan. ae11003@student.miyazaki-u.ac.jp 

To analyze protein expression of pollen tubes having self-incompatible reactions in hyuganatsu (Citrus 

tamurana), mature pollen was cultured and treated with crude extracts from styles using the mass or single 

liquid culture system and pollen tubes were collected for proteome analysis. The relative expression of 

each identified protein was quantified by Imager and revealed as a value relative to the pollen grain. Eleven 

identified proteins were remarkably up-regulated (above 1.2-fold) or down-regulated (under 0.8-fold) in the 

treatment with crude extract from self-pollinated styles. Seven of these proteins were predicted to be related 

to the SI reaction between the reported function of these seven proteins. In this study, F-box protein was 

identified as showing minimum expression in the treatment with extract from styles of wild-type hyuganatsu. 

The S-locus gene product expressed in pollen has been identified as an F-box protein in Solanaceae and 

Rosaceae. It is not clear whether a mechanism similar to that in Solanaceae and Rosaceae exists in the SI 

reaction in hyuganatsu, however, the reduced expression of F-box protein may induce an SI reaction. 

S07P06 

Hormone complex and micronutrients in production and fruit quality of ‘Valencia’ sweet orange 

Galván J.J., López N., and Tolentino A. 

UAAAN (UA), Horticultura, Saltillo. juan.galvan@uaaan.mx, doctorgalvanluna@hotmail.com 

A complex hormone (Biozyme ® TF) was applied with micronutrients (Zinc poliquel and multi) at different 

concentrations and we evaluated the effects on both quality and performance of the fruit of ‘Valencia’ sweet 

orange in 20 year-old trees. Tree were located near the Eugenia Huerta Montemorelos Monterrey road Km 

66, Gil de Leyva Montemorelos Nuevo Leon, Mexico, between 25° 11’ 24” north latitude and 99° 41’ 33” west 

longitude of Greenwich, with an altitude of 423 m and a rainfall of 600 to 1.000 mm. The prevailing weather 

was semi-warm with an annual average temperature of 18º C to 22º C and humid with rains intermediate in 

summer and winter. The variables evaluated were fruit weight (FW), equatorial diameter (DE), polar diameter 

(DP), thickness of the peel (GC), fruit firmness (F), % juice content (CJ), volume of juice (VJ), weight of juice (PJ), 

º Brix (GB), pH of the juice, citric acid % (AC), vitamin C, color ratio L * a * b * and number of seeds per fruit. The 

results show that treatment of Biozyme Poliquel Zn), positively affected the majority of the variables evaluted. 

S07P07 

Effects of Triclopyr (3,5,6-trichloro-2-pyridyloxyactetic acid) applications on fruit quality of 

SRA63, SRA85, SRA88 and SRA92 clementines 

Zurru R. 1 , Deidda B. 1 , Dessena L. 2 , and Mulas M. 2 

1 AGRIS-Sardegna (AGRIS), Department of Wood and Fruit Tree Research, Italy; and 2 University of Sassari (DIPNET), Department of the 

Nature and Land Sciences, Italy. mmulas@uniss.it 

In order to improve the yield and quality of clementine fruit, many treatments with hormonal compounds 

were carried out during the last 8 years in the south of Sardinia (Italy). The main objectives of the research 


S07

S07 

program were to increase fruit set, control fruit thinning, increase fruit size at harvest, reduce fruit drop 

during maturation, and to maintain on-tree fruit quality storage particularly of the peel. Four different 

cultivars of clementine were tested: ‘SRA63’, ‘SRA85’, ‘SRA88’, and ‘SRA92’; as well as two rootstocks: sour 

orange and ‘Carrizo’ citrange. In this paper, the effects of Triclopyr (3,5,6-trichloro-2-pyridyloxyactetic acid), 

as an alternative to 2,4-D (dichlorophenoxyacetic acid), were evaluated for the control of the pre-harvest 

natural drop. Triclopyr treatments were more effective to control fruit drop and to protect the peel of the 

mature fruit when applied early on fruit of 18-22 mm of diameter (about the middle of July) with respect to 

treatments made at peel colour break time. This treatment in middle July alone determined the increase in 

fruit size and sometimes the total yield per tree. Lower yield was generally observed in trees grafted on sour 

orange than on ‘Carrizo’ rootstock. Triclopyr showed a strong thinning effect when applied to fruit of 6-13 mm 

of diameter, thus negatively affecting quantity and quality of the yield. On the contrary, Triclopyr treatments 

at peel colour break time allowed normal colour development. 

S07P08 

Foliar application effect of the 3,5,6-TPA on Tarocco red orange yield and fruit size in “on years” 

of eastern Sicily orchard 

Tumminelli R., Marano G., Carta Cerella D., and Sinatra V. 

Servizio Fitosanitario Regionale Siciliano (SFRSICILY), Quarantine and crop protection service, Italy. 

riccardo.tumminelli@regione.sicilia.it 

In the last four years (2009-2012), a method of reducing alternate bearing of red oranges (Citrus sinensis) 

of eastern Sicily was investigated. In 2009 and 2011, 3,5,6-trichloro-2-pyridyloxyacetic acid (3,5,6 TPA) 

treatments were tested for their ability to increase yield of commercially valuable large size red orange fruit 

(6 - 8 cm transverse diameter). Commercially bearing 15-year-old ‘Tarocco’ red orange scion on sour orange 

rootstock (C. aurantium) was used in this research. 3,5,6 TPA (30 g a.i./ha) plus 0.7% of paraffinic narrow range 

mineral oil were applied in 3000 L of water (pH 7.0) per ha with a low-profile air-blast sprayer to the foliage of 

one individual tree per treatment with 4 replicate trees per treatment when fruit averaged 10 mm transverse 

diameter. Four untreated trees served as the control. Averaged across the 4 years of the experiment, 3,5,6- 

TPA treatments in 2009 and 2011, reduced total yield and increased yield of commercially valuable large size 

fruit in the ‘on’ years 2010 and 2012, and increased total yield and decreased commercially valuable large size 

fruit in the ‘off ‘ year 2011. Flower induction in 2012 was increased in treated trees in set fruit that will reach 

maturity during the ‘off’ year 2013. 

S07P09 

Fruit thinning of ‘Okitsu’ satsuma mandarin 

Rivadeneira M.F1 , Gómez C. 1 , and Silva-Muller W. 2 

1Instituto Nacional de Tecnología Agropecuaria. Estación Experimental Agropecuaria Concordia (INTA EEA Concordia), Entre Ríos, 

Argentina; and 2Ando Cia. frivadeneira@correo.inta.gov.ar 

The plant growth regulator naphthalene acetic acid (NAA) is used as a fruit thinning agent before the 

physiological drop stage of citrus fruit. Chemical and manual fruit thinning of ‘Okitsu’ satsuma mandarin 

(Citrus unshui) was studied in an experiment carried out at Concordia, Entre Ríos, Argentina. In the spring of 

2010 and 2011, fourteen-year-old mandarin trees grafted on Poncirus trifoliata rootstock were sprayed with 

NAA (at 0, 100, 200 mg L -1 ) 40 days after full bloom (DAFB). Manual thinning was done at 80 DAFB. Treatments 

were: control (0 NAA), manual thinning (MT), 100 mg L -1 NAA, 100 mg L -1 NAA with MT, 200 mg L -1 NAA and 

200 mg L -1 NAA with MT. Fruit number, cross sectional shoot area, and fruit diameters were measured at 40, 

70, 120 and 160 DAFB in two shoots per tree. Yield per tree was recorded at commercial harvest time in three 

trees per treatment. Physiological fruit drop at 70 DAFB was 20-26% and with NAA fruit drop was 30-48%. 

In the first year, there was no significant effect in yield per tree or diameter of fruit at harvest, although NAA 

increased the number of fruits with larger diameters. Chemical thinning might be a useful tool to improve 

commercial harvests in ‘Okitsu’ satsuma mandarin. 


S07P10 

Transcript accumulation of flowering genes in response to water deficit and gibberellins during 

floral induction in Citrus sinensis 

Chica E.J., and Albrigo L.G. 

University of Florida Citrus Research and Education Center (UF/IFAS CREC), Horticultural Sciences, United States. 

jchica@espol.edu.ec 

Temperature, tree water status, crop load and gibberellins are the only factors known to modify floral induction 

in Citrus sinensis. Recently, several groups have characterized the accumulation of transcripts of floweringrelated 

genes in response to temperature and crop load, but reports on the effect of tree water status and 

gibberellins on the expression of these genes are lacking. Here we report the patterns of accumulation of 

CsFT, CsSL1, CsAP1 and CsLFY transcripts in response to water deficit and gibberellin treatments. Under water 

deficit, the accumulation of CsFT transcripts increased as the time under water deficit increased. Conversely, 

the accumulation of CsSL1, CsAP1 and CsLFY transcripts was reduced while trees remained under water 

deficit. After the water deficit was interrupted, accumulation of CsFT transcripts returned to initial stress 

levels whereas the accumulation of CsSL1, CsAP1 and CsLFY transcripts increased. A similar response was 

observed when trees were exposed to water deficit and floral-inductive temperatures. In general, application 

of gibberellins (GA3) reduced the accumulation of transcripts of all 4 genes. These results show that exposure 

to water deficit induces a response in the accumulation of transcripts of flowering-related genes similar to 

that induced by low ambient temperatures and that gibberellins partially inhibit the up-regulation of these 

genes. 

S07P11 

The effect of ethyclozate on tree water stress and fruit quality of satsuma mandarin 

Okuda H.O 1 , Ichinokiyama H.I. 2 , and Noda K.N. 3 

1 Faculty of bioresources, Mie University, Japan; 2 Mie prefecture agricultural research institute, Japan; and 3 Center for environment, 

health and field sciences, Chiba University, Japan. okudat@bio.mie-u.ac.jp 

The fruit quality of satsuma mandarin strongly depends on drought stress during the maturation period. 

Most commercial orchards in Japan receive significant amounts of rain during the maturation period. To 

obtain the highest quality fruit, water vapor-permeable sheets are being used to cover the ground (mulching) 

in approximately 20 percent of the very early satsuma mandarin orchards in Japan. However, such sheets 

are ineffective in citrus fields converted from paddy fields. Chemicals, such as ethyclozate, might be used 

to improve fruit quality as a substitute for mulching for applying water stress because this chemical could 

reduce water uptake through roots. This effect was notable only in young trees but there was no report of 

effects in mature trees. In this experiment, seasonal changes in the volumetric water content (VWC) in the 

trunk of mature trees were monitored along with the effects of the chemical. The results suggested that VWC 

decreased in the treated trees from early July immediately after treatment until early September. In addition, 

coloring began to occur one week earlier, and the brix increased by about one degree at harvest. These 

results suggest that the application of ethychlozate in early summer might play a role for applying water stress 

to improve fruit quality. 

S07P12 

Relationship between flower intensity, oxidative damage and protection in citrus under water 

stress conditions 

Manzi M. 1 , Borsani O. 2 , Díaz P. 2 , and Rivas F. 3 

1 Universitat Jaume I (UJI), Ciencias Agrarias y del Medio Natural, Spain; 2 Facultad de Agronomía - Universidad de la República (FAgro - 

UdelaR), Biología Vegetal, Uruguay; and 3 Instituto Nacional de Investigación Agropecuaria (INIA), Programa Nacional de Investigación 

en Producción Citrícola, Uruguay. mmanzif@gmail.com 

Stress conditions are known to promote reproductive sprouting and flowering in citrus. However, signalling 

involved in stress perception and flowering induction remains obscure. To gain insight into the mechanism 


S07

S07 

involved in stress signalling, the aim of this work was to study the physiological and biochemical changes 

triggered by water stress and their relationship with budbreak in ‘Valencia’ sweet orange (Citrus sinensis) 

and ‘Ellendale’ tangor (C. reticulata x C. sinensis). Photoinhibition was promoted by subjecting plants to 70days 

of water deficit (water potential: Ψw

Session 08 

ABIOTIC STRESS 

S08

S08O01 

Polyamines: a key player in stress response 

Liu J.-H. 

Key Laboratory of Horticultural Plant Biology, Ministry of Education, College of Horticulture and Forestry Sciences, Huazhong 

Agricultural University, Wuhan, China. liujihong@mail.hzau.edu.cn 

Polyamines, mainly putrescine, spermidine and their diamine precursor spermine, are polycationic lowmolecular-mass 

aliphatic amines that are ubiquitously distributed in living organisms. Polyamines have 

been shown to be closely implicated in plant biotic and abiotic stress response. In the last years we have 

carried out work to identify the role of polyamines in stress response of citrus or its closely related genus. 

The major work is following. First, analysis of polyamine levels in different tissues under stressful condition. 

Second, investigation of exogenously applied polyamines on the enhancement of dehydration tolerance. 

Third, molecular cloning and functional characterization of polyamine biosynthetic genes, such as arginine 

decarboxylase (ADC) and S-adenosylmethionine decarboxylase (SAMDC). Last, polyamine biosynthetic genes 

were used for genetic engineering in an effort to producing novel germplasms with enhanced stress tolerance. 

Our data showed that PtADC from Poncirus trifoliata was upregulated by different types of stresses, including 

salt, low temperature, dehydration. Ectopic expression of PtADC gene conferred enhanced tolerance to 

different stresses in transgenic plants. All these results show that polyamines are important players that can 

be manipulated to increase stress tolerance in citrus. 

S08O02 

‘Omics’ and chemical approaches used to monitor iron-deficiency in citrus rootstocks 

Licciardello C. 1 , Muccilli V. 2 , Torrisi B. 1 , Tononi P. 3 , Fontanini D. 4 , Allegra M. 1 , Sciacca F. 1 , Foti S. 2 , Delledonne M. 3 , Intrigliolo 

F. 1 and Reforgiato Recupero G. 1 

1 Research Centre for Citriculture and Mediterranean crops (CRA-ACM), Italy; 2 University of Catania, Department of Chemical Science, 

Italy; 3 University of Verona, Department of Biotechnology, Italy; and 4 University of Pisa, Department of Biology, Italy. 

concetta.licciardello@entecra.it 

Two different ‘omics’ approaches were performed to a better comprehension of biological mechanisms involved 

in citrus iron deficiency. Tips roots from ‘Swingle’ citrumelo and ‘Carrizo’ citrange (sensitive and tolerant 

rootstocks, respectively), growing in pots with control and chlorotic soil, were used for transcriptomic and 

proteomic analysis. CombiMatrix array was performed to isolate differential genes, among which glutathione 

peroxidase and SAUR gene showed to be the most involved ones. They were switched on ‘Swingle’ citrumelo 

grown on calcareous conditions compared to ‘Carrizo’ citrange (in the same soil) and to the same stock in 

the control soil. The over-expression of peroxidase could be the effort of plants to neutralize the oxidative 

environment produced by stress. The involvement of auxin in the regulation of Fe deficiency responses is 

also well known. Both genes, together with peroxidase and ferric chelate reductase activities and iron and 

chlorophyll content, were used as markers to monitor the degree of suffering on seven tolerant and sensitive 

rootstocks growing on the field under natural chlorotic conditions. Among differentially expressed proteins, 

isolated using 2D-PAGE and RP-HPLC/nESI-MSMS, a strong down-regulation of cytosolic pyrophosphatedependend 

phosphofructokinase beta subunit and NADPH-isocitrate dehydrogenase could produce plant 

inability to sustain the energetic request of cell roots. 

S08O03 

Root protein interatomic network obtained from citrus seedlings subjected to water deficit 

Magalhães de Oliveira T. 1 , Silva F. 2 , Morillon R. 3 , Coelho Filho M.A. 4 , Neves D.M. 1 , Costa M.G.C. 1 , Pirovani C.P. 1 and 

Bonatto D. 2 

1 Universidade Estadual de Santa Cruz (UESC), Brasil; 2 Universidade Federal do Rio Grande do Sul (UFRGS), Brasil; 3 CIRAD, France; and 

4 Embrapa Mandioca e Fruticultura, Brasil. tmaga21b@gmail.com 

Citrus Brazilian industry may be strongly affected by drought. Characterize rootstock behavior under different 

environmental conditions is crucial, since rootstocks may confer better adaption to environmental stresses. 

Plant responses to drought require the production of important functional and regulatory proteins. In the 


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present study, we identified proteins related to water deficit response in tolerant (‘Rangpur’ lime, Citrus 

limonia) and susceptible (‘Sunki Maravilha’ mandarin, Citrus sunki) genotypes. From 105 differentially 

expressed proteins, twenty-nine proteins from roots of both genotypes were identified and sequenced by 

mass spectrometry. Protein interaction analysis of orthologous proteins from A. thaliana protein expressed in 

the two citrus varieties was obtained by ontological and cluster analysis.Among the 16 amino acid sequences 

found in ‘Rangpur’ lime and ‘Sunki Maravilha’ mandarin, 13 proteins were found in A. thaliana via BLAST, of 

which, 12 showed protein-protein interaction. It is possible to group these 12 proteins into a single network 

interatomic, comprising 3302 proteins. Among the different biological processes found in the protein 

networks, regulation of response to water deficit and osmotic stress, signaling pathway of abscisic acid were 

highlighted. A point to take into account is the importance role of the DREB2, a protein hub/bottleneck which 

participate in the stimulus and the response to water stress. 

S08O04 

Hormone and metabolite traits related to abiotic stress tolerance in citrus 

Arbona V., de Ollas C., Argamasilla R., López-Climent M.F. and Gómez-Cadenas A. 

Universitat Jaume I (UJI), Dept. Ciències Agràries i del Medi Natural, Spain. arbona@uji.es 

Plants of the citrus rootstocks ‘Carrizo’ citrange (CC, soil flooding tolerant) and ‘Cleopatra’ mandarin (CM, 

drought tolerant) were subjected to water stress and soil flooding conditions to study root responses associated 

to tolerance. Responses could be classified in groups which different involvement in plant tolerance. Some of 

them, such as the increase in proline levels, were common to the two species and the two stress conditions 

assayed. Other, as the abscisic acid and jasmonic acid signals or the phenylpropanoid profiles followed similar 

trends in both species varying with the stress imposed. Finally, other responses as the increase in salicylic acid 

were specific of each genotype and stress situation. Moreover, following a metabolomics approach, it was 

showed that the altered compounds in response to each adverse condition had a low degree of overlapping 

which accounts for the specificity of the plant response to the different environmental restraints. Finally, 

under control conditions, different metabolites had higher levels in CM than CC which suggested that preexistent 

defenses are important as a stress tolerance trait. 

S08O05 

The adaptation of ‘Sunki Maravilha’ mandarin to drought depends on the ABA accumulation 

balance between roots and canopy 

Neves D.M. 1 , Coelho Filho M.A. 2 , Bellete B.S. 3 , Silva M.F.G.F. 3 , Souza D.T. 4 , Soares Filho W.S. 4 , Costa M.G.C. 1 and 

Gesteira A.S. 4 

1Universidade Estadual de Santa Cruz (UESC), Departamento de Ciências Biológicas, Brasil; 2Embrapa Mandioca e Fruticultura 

(CNPMF), Renai, Brasil; 3Universidade Federal de São Carlos (UFSCar), Departamento de Química, Brasil; and 4Embrapa Mandioca e 

Fruticultura (CNPMF), Nugene, Brasil. asgesteira@gmail.com 

Abscisic acid (ABA) is an important plant hormone that participates in the adaptation to many abiotic stresses 

such as drought. The 9-cis-epoxycarotenoid dioxygenase (NCED) is the key enzyme of ABA biosynthesis in 

higher plants. The importance of ABA in two citrus varieties of rootstock, the ‘Rangpur’ lime and the ‘Sunki 

Maravilha’ mandarin, cultivated on hydric restriction by expression analysis of five NCED genes and correlation 

with the accumulation of ABA were evaluated. In the ‘Rangpur’ lime the profile of ABA accumulation ratifies 

that perception and induction of adaptation signals against water stress occurs from the roots and leads to 

a decrease in transpiration. However, this decrease is not sufficient to reduce the water flow from roots to 

canopy keeping its active growth even in conditions of low water availability. Instead, the adaptation of ‘Sunki 

Maravilha’ mandarin depends on the balance of ABA accumulation between root and canopy which increases 

with water restriction, inducing a decrease in transpiration rate and water flow from roots to canopy. Under 

drought, water requirement for ‘Sunki Maravilha’ mandarin decreases and it adapts to a lower availability of 

water in the soil. The use of this mandarin in combination with a scion variety with characteristics similar to 

its own, that responds to stress by water deficit with ABA accumulation in leaves, may have good drought 

tolerance under field conditions. In this study we correlated the NCEDs with ABA accumulation. 


S08O06 

Roots are necessary for the responses of in vitro-cultured citrus plants to high salinity but not to 

osmotic stress 

Pérez Clemente R.M., Montoliu A., Vives-Peris V., Espinoza V., Zandalinas S.I. and Gómez-Cadenas A. 

Universitat Jaume I (UJI), Dept. Ciències Agràries i del Medi Natural, Spain. rclement@uji.es 

In the field, plants are exposed simultaneously to variable biological and environmental conditions that 

can make physiological studies very difficult. The in vitro tissue culture techniques can overcome some of 

these limitations. In the present work, this methodology was applied to the study of salt and osmotic stress 

conditions on ‘Carrizo’ citrange. The stress conditions were generated by adding either NaCl or polyethylene 

glycol, to the culture medium. Micropropagated shoots, growing under salt- or osmotic-stress, shown 

symptoms of leaf damage very similar to those found in intact plants, which confirmed the incidence of 

the imposed stress on plant physiology. In whole plants, it has been reported that physiological responses 

to water and salt stress are essentially identical; on the contrary, in shoots cultured in vitro, levels of 

stress markers such as malondialdehyde and proline incrased only under water deficiency but not under 

elevated salt conditions Differences were also observed in the hormonal regulation of the shoots subjected 

to each abiotic stress condition. Abscisic acid concentration increased in shoots grown under osmotic 

stress conditions whereas no differences with the controls were observed in salt-stressed ones. It can be 

concluded that, at least when culture in vitro, citrus roots are necessary for the perception and signaling 

of the salt stress conditions. On the contrary, the presence of this organ is not necessary to modulate the 

response of shoots to osmotic stress. 

S08O07 

Physiological analysis of salt stress behaviour of citrus species and genera: low chloride 

accumulation as an indicator of salt tolerance 

Hussain S. 1 , Luro F. 2 , Costantino G. 2 , Ollitrault P. 3 and Morillon R. 3 

1 Bahauddin Zakariya University Multan, Department of Horticulture, Pakistan; 2 INRA Unité de Recherche 1103 Génétique et 

Ecophysiologie de la Qualité des Agrumes, France; 3 Unité Mixte de Recherche Amélioration génétique et Adaptation des Plantes, 

CIRAD - Instituto Valenciano de Investigaciones Agrarias (IVIA) Equipe Amélioration des Plantes à Multiplication Végétative, Spain. 

sajjad_h@yahoo.com 

Tolerant citrus rootstocks are defined as Cl- excluders. However, little is known about the salt tolerance of 

cultivars used as scions, particularly the tolerance of monoembryonic citrus genotypes. To enhance the 

genetic resources for generating improved hybrid rootstocks, the evaluation of large samples of citrus species, 

including both monoembryonic and polyembryonic genotypes, is necessary. In this study, 12 citrus genotypes 

representing the major Citrus species and all the three genera of the Rutaceae family were subjected to 

moderate salt stress (75mM) for 12 weeks to characterise their physiological response to salt stress. Various 

symptoms and physiological parameters were evaluated to characterise their salt sensitivity. These included 

plant growth (stem diameter), leaf chlorophyll content, leaf flavonoid content, maximum quantum yield of 

PSII [(Fm-F0)/Fm)], net photosynthesis, stomatal conductance and leaf Na and Cl- contents. The results clearly 

demonstrated that the most salt sensitive genotypes accumulated high concentrations of Na and Cl- and 

maintained a fair growth and photosynthetic rate. By contrast, salt-tolerant genotypes accumulated less Na 

and Cl- and decreased their growth and gas exchange. ‘Poncire commun’ citron and ‘Marumi’ kumquat were 

the most sensitive species, while mandarins, pummelo and ‘Australian’ sour orange were the most tolerant 

species. Among the genotypes, ‘Engedi’ pummelo presented a specific trait for salt tolerance that has not 

been previously reported. Taken together, the results suggest that low leaf chloride content can be used as 

an indicator of salt stress tolerance in citrus genotypes. Exploitation of this indicator will enable the improved 

evaluation of citrus genetic resources and should lead to the identification of new sources of tolerance for 

rootstock breeding. 


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S08O08 

Microsprinkler irrigation for frost protection of citrus in Florida 

Parsons L.R. 

University of Florida (UF CREC), Citrus Research & Education Center, USA. lparsons@ufl.edu 

In 1979, it was not known if microsprinkler irrigation could provide any frost protection for citrus, and 

some assumed that this irrigation would not. Tests during freezes between 1980 and 2010 showed that 

microsprinklers were effective in protecting the lower 0.9 m of young citrus trees, thereby saving the 

bud union and allowing later regrowth. Microsprinklers also benefit mature trees. The amount of air 

temperature warming depends on several factors, including volume of water applied & wind speed. 

Microsprinkler irrigation is more effective for cold protection when higher volumes of water are applied. 

Irrigation rates of 18.7 m3 ha -1 hr -1 have been recommended. At these rates, average air temp warming 

at a 1.3 m height is 1 to 1.5°C. At tree heights of more than 2.6 m, warming is commonly less than 0.5°C. 

In windy, low humidity freezes, evaporative cooling can damage trees, particularly if the emitter is on the 

downwind side of the tree. Protection is better if the microsprinkler is placed on the upwind (northwest in 

Florida) side of the tree. Microsprinklers elevated to a height of 0.6 to 1 m protect more of the tree than 

those at 0.2 m. While it was initially thought that microsprinklers provided no frost protection to the fruit, 

recent research has shown that this irrigation can promote better production of kg of soluble solids than 

when no irrigation is used. Microsprinkler irrigation has become the most commonly used form of frost 

protection in Florida citrus. 

S08P01 

Response of ‘Washington’ navel orange plants to application of Helpstar and Saltrad as saline 

correctors 

El-SHazly S.M. 1 , Eisa A.M. 1 and Sarhan Z.H. 1 

1Faculty of Agriculture, Alexandria University, Pomology Department, Egypt. samyshazly55eg@yahoo.com 

The aim of this study is to evaluate the effect of different salinity levels (zero, 1500, 3000 and 4500 ppm 

NaCl) and salinity correctors Saltrad (CaO) and Helpstar (K 2 O) at (zero, 5 and 7.5 cm 3 / pot / month) on 

vegetative growth parameters, and leaf and root chemical composition of ‘Washington Navel’ orange plants. 

The results indicated that all vegetative growth parameters (growth rate, plant height, stem diameter, root 

length, volume index and trunk cross sectional area), leaf chlorophyll content, leaf peroxidase activity and 

leaf and root contents of carbohydrates, N, P, K, Ca and Mg have decreased, meanwhile leaf and root proline 

and Na and Cl contents have increased with salinity increments. Salinity correctors enhanced all vegetative 

growth parameters, chlorophyll, peroxidase activity, proline, carbohydrates and N, P, K, Ca and Mg contents, 

meanwhile Na and Cl were reduced. Generally, it can be concluded that using Saltrad at 7.5 cm 3 /pot / month 

gave the highest values of vegetative growth parameters and leaf and root chemical composition. Due to lack 

of significance – in most parameters- between Saltrad treatments at 5 and 7 cm 3 /pot, we recommend the 

use of Saltrad at 5 cm 3 /pot / month to reduce the negative impact of salinity on ‘Washington’ navel orange 

plants. 

S08P02 

Effects of salinity on some citrus rootstocks 

Yeşiloğlu T. 1 , İncesu M. 1 , Yılmaz B. 1 , Tuzcu Ö. 1 , Uysal Kamiloğlu M. 2 and Çimen B. 1 

1University of Cukurova (CU), Department of Horticulture, Turkey; and 2University of Mustafa Kemal (MKU), Department of 

Horticulture, Turkey. meralincesu@gmail.com 

Citrus is a major horticultural crop worldwide and known as relatively susceptible to salinity. Salt damages 

are usually displayed as leaf burn and defoliation and are associated with accumulation of toxic levels of 

Na and/or Cl − in leaf cells. Reactions against these toxicities depend on the rootstock used. In this study 

we have evaluated ‘Tuzcu 891’ sour orange, ‘Swingle’ citrumelo, ‘Volkameriana’, ‘Rubidoux’ trifoliate and 


‘Citremon’ in terms of salinity. The experiment was carried out in a greenhouse. The treatments were control 

[nutrient solution with electrical conductivity [EC(w) of 0.41 dS m( -1 )] and salinity [nutrient solution with 

EC(w) 6.0 dS m( -1 )] in a randomized block design with -thirty replicants -during 90 days period. Thus shoot 

and root dry weights, leaf and root potassium (K) concentrations, leaf and root calsium (Ca) concentrations, 

leaf and root chloride (Cl) concentrations, leaf and root sodium (Na) concentrations and symptoms in leaves 

were observed. Although root dry weight did not differ among those rootstocks, significant differences were 

determined in K, Ca, Cl, Na concentrations and shoot dry weights. 

S08P03 

Salt stress tolerance in acidic and sweet mandarins 

Ben Yahmed J. 1 , Ben Mimoun M. 2 , Talon M. 3 , Ollitrault P. 1 and Morillon R. 1 

1Centre de coopération internationale en recherche agronomique pour le développement (CIRAD), Amélioration des Plantes à 

Multiplication Végétative, France; 2Institut National Agronomique de Tunisie (INAT), Tunisie; and 3Centro de Genomica, Instituto 

Valenciano de Investigaciones Agrarias (IVIA), Spain. jihene.benyahmed@gmail.com 

Mandarin genotypes can be split in two main groups: the acidic and the sweet mandarins. Acidic are used 

as rootstocks whereas sweet mandarins are the varieties that are consumed for fruits. The acidic ‘Cleopatra’ 

mandarin (Citrus reshni) is considered to be the most salt stress tolerant rootstock since it is able to limit 

the absorption of chloride and sodium at root level. As a consequence, limited amount of toxic ions are 

translocated to leaves of the seedling or the variety grafted onto the rootstock. If salt stress tolerance of 

‘Cleopatra’ mandarin and its hybrids has been quite documented, little data exist for sweet mandarins. 

We investigated 16 genotypes representing the large diversity of mandarins when subjected to salt stress. 

Physiological parameters such as gas exchanges, quantum yield of PSII electron transport, osmotic pressure 

and leaf chloride contents were analyzed. Samples were also harvested for molecular and biochemical 

analysis. Very different behaviors were observed. If most of the acidic varieties were considered to be tolerant, 

also some sweet varieties showed traits of tolerance. Taking account of the results of leaf ion contents, we 

observed that large leaf chloride contents were not always associated with sensitivity. Molecular analyses are 

going on to decipher the origin of the tolerance in these genotypes. 

S08P04 

Changes in transcriptional profiles of mature and immature citrus leaves acclimated to salinity 

Pérez-Pérez J.G. 1 , Talón M. 2 , Brumós J. 2 , Botía P. 1 and Colmenero J.M. 2 

1Instituto Murciano de Investigación y Desarrollo Agrario y Alimentario (IMIDA), Department of Citriculture, Spain; and 2Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Genómica, Spain. juang.perez@carm.es 

While the molecular response of salinized plants in the short-medium term (hours-days) has been broadly 

studied, the knowledge about the nature of the genes involved in maintaining homeostatic conditions the 

long term (months-years) has remained elusive. With this aim, we have analyzed the transcriptome of 

leaves from citrus plants acclimated to moderate salinity (2 years with NaCl 30 mM). Through functional 

genomics, using the 7K cDNA chip from “Consorcio Valenciano de Genómica Funcional de Cítricos”, the 

transcriptome of citrus plants acclimatized to salinity was analyzed in mature leaves (8 months) and 

immature leaves (2 months). Although immature leaves accumulated low levels of chloride (0.51%±0.06), 

they exhibited high responsiveness to salinity (1,211 differential-responsive genes) compared with 

mature leaves, which cumulated higher chloride levels (1.05% ± 0.01), and showed a lower number of 

differentially-responsive genes (100 genes). Immature leaves induced functional categories that were not 

induced in mature leaves, like ”cell wall biosynthesis”, “metabolism”, “defense”, “secretion and membrane 

traffic”, “water transport” and “antioxidant activity”. On the other hand, the degree of coincidence 

was higher in the group of genes that were repressed by salinity. Both mature and immature leaves 

repressed genes mostly involved in “stress response”. We highlight how the same plant organ in different 

developmental stages show huge differences in the amount and nature of genes which are responding to 

an abiotic stimulus. 


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S08P05 

Role of ammonium nutrition on salt-induced oxidative stress in ‘Carrizo’ citrange plants 

Fernández-Crespo E. 1 , Gómez-Pastor R. 2 , Matallana E. 2 , Llorens E. 1 , Lapeña L. 1 , Scalschi L. 1 , Camañes G. 1 and García-Agustín P. 1 

1 Universitat Jaume I (UJI), Ciencias Agrarias y del Medio Natural, Spain; and 2 Universitat de Valencia (UV), Bioquímica y Biología 

Molecular, Spain. ellorens@uji.es 

Salinity is amongst the most significant environmental factors responsible for substantial losses in agricultural 

production worldwide and it is a critical problem especially in citrus since they are one of the most globally 

important horticultural crops considered as salt sensitive. Salt stress has two effects on plants, an initial osmotic 

shock followed by a toxic phase due to ion accumulation. Moreover, a high cellular NaCl concentration enhances 

accumulation of reactive oxygen species (ROS). To avoid such salt stress-derived injuries, tight regulation of ROS 

homeostasis is necessary and is provided by a network through complex loops between oxidants and scavengers. 

NH4is a paradoxical nutrient ion because it is a main N source, but high concentrations of this ion in the soil 

may cause damaging effects. In this study, we have analyzed the influence of NH 4 nutrition on ‘Carrizo’ citrange 

plants undergoing 90 mM NaCl. Plants were grown with 1 mM NH 4 NO 3 (control) and 5 mM N-NH 4 . To clarify 

the relationship between the antioxidant mechanisms induced by ammonium nutrition and salt tolerance, 

we analyzed enzymatic antioxidant activities (SOD, CAT, GR), ascorbate and glutathione concentrations and 

antioxidant properties of proline and putrescine. ‘Carrizo’ plants showed optimal growth in both treatments and 

we confirmed that N-NH 4 treatment enhance resistance to salt stress. Based on this evidence, we hypothesized 

that N-NH 4 treatment triggers mild chronic stress in ‘Carrizo’ which could prime plant defenses by stress imprinting, 

thus conferring plant resistance. Moreover, subletal concentration of ammonium could act as a mild oxidative 

stressor triggering antioxidant cellular machinery against subsequent salt stress. 

S08P06 

Characterization of the Arum-type mycorrhiza in Citrus macrophylla rootstock under salinity stress 

Rodríguez Morán M. 1 , Navarro J.M. 1 and Morte A. 2 

1 Departamento de Citricultura, IMIDA, Murcia 30150, Spain; and 2 Departamento Biología Vegetal y Botánica, Facultad de Biología, 

Universidad Murcia 30100, Spain. ringil_1@hotmail.com 

Arum and Paris mycorrhizas are two major morphological classes of arbuscular mycorrhizal (AM) symbiosis which 

differ in fungal structures. AM symbiosis is thought to increase host resistance to salinity stress, a characteristic that 

could be interesting in areas where the scarcity of irrigation waters force to growers to use low-quality irrigation 

water. The type of AM colonization was analyzed in order to study if it is influenced by saline conditions. Seedlings 

of Citrus macrophylla (CM) were inoculated with a mixture of two AM fungi. Ninety-six days after inoculation, 

plants were irrigated with Hoagland modificated solution containing 0, 20, 40, 60 and 80 mM NaCl. CM showed 

an Arum-type mycorrhiza. Epidermical cells were never colonized and, the infection developed longitudinally and 

radially in the cortex of the root by many intercellular hyphae. Branches from intercellular longitudinal hyphae 

gave rise to arbuscules in the cells. These arbuscules were scattered in the cells of the medium and inner cortex, 

with the outer cortical cell layers relatively free of intracellular fungal structures. The vesicles were also located 

in the intercellular spaces of the same cortical cell layers. Most of the mycorrhizal roots under salt treatments 

showed an increasing number of vesicles respect to mycorrhizal roots without salt treatment. Under salinity 

stress, no differences were observed in the mycorrhizal colonization percentages. This could explain the observed 

increasing tolerance of mycorrhizal plants under high level of salinity. 

S08P07 

In vitro screening of four genotypes of citrus for salt tolerance 

Chetto O. 1 , Dambier D. 2 , Fadli A. 1 , Talha T.A. 3 , Benkirane R. 1 and Benyahia B.H. 3 

1 Ibn Tufail University (UIT), Morocco; 2 Center for International Cooperation in Agronomic Research for Development (CIRAD), Genetic 

Improvement of Vegetatively Propagated Species, France; and 3 National Institute of Agronomic Research (INRA), Laboratory of Citrus 

Improvement and Biotechnology, Morocco. ouiam_ch@hotmail.com 

Soil and water salinity is an important abiotic stress that can affect both production and quality of citrus. The 

use of tolerant rootstocks in these conditions would be the solution the most used. The objective of this study 


was to compare in vitro behavior of four citrus genotypes in terms of tolerance to salinity. The genotypes used 

were ‘Cleopatra’ mandarin, ‘Chios’ mandarin, ‘Shamouti’ orange and ‘Star Ruby’ grapefruit. Salt tolerance was 

evaluated by determination of callus and suspension cells growth, the fresh and dry weight, water content and 

chloride ion content after one month of culture in solid and liquid media supplemented with NaCl at different 

concentrations: 50, 100, 150 and 200 mM. At 0 mM NaCl, the results revealed that callus of the four genotypes 

tested have a similar behavior in term of tolerance to salinity as the suspension cells. However, a differential 

behavior was observed at high salt concentrations depending on genotypes and the nature of medium. 

S08P08 

Screening of ten citrus rootstocks for salt tolerance at seedling stage 

Fadli A. 1 , Chetto O. 1 , Talha A. 2 , Beniken L. 2 , Benkirane R. 1 and Benyahia H. 2 

1Ibn Tofail University (UIT), Department of Plant Science, Kenitra, Morocco; and 2Kenitra Regional Center for Agricultural Research 

(CRRAK), Department of Plant Breeding and Phytogenetic Ressources Conservation, Kenitra, Morocco. a.fadli.uit@gmail.com 

Salinity affecting 35% of Moroccan irrigated soils represents a serious problem for citrus production in these 

areas. Furthermore, the wide spread of Tristeza disease in the mediterranean region will soon limit the use 

of sour orange which is a salt tolerant rootstock commonly used in Morocco. Since then, the selection of new 

salt tolerant rootstocks has become an important research area for citrus breeding programs. In this study, 

nine citrumelo (C.) rootstock lines i.e. ‘C. 57-98-502’, ‘C. 57-98-506’, ‘C. 4475 BB6A9’, ‘C. 4475 AB6A4’, ‘C. 4475 

B2.G3’, ‘C. sacaton 30057’, ‘C. Swingle 74.1’, ‘C. Swingle F.9.22.5 (80.1)’ and ‘C. Winter Haven B231431’ were 

evaluated for salinity tolerance by applying a fast test of screening. The seedlings of these rootstocks were 

grown in greenhouse conditions and treated for two months with a saline solution containing NaCl at 0, 35 

and 85 mM concentrations. ‘Rangpur’ lime was included in the experiment as control. The results showed a 

wide variation of response. At high level of salinity (85 mM), ’C. Winter Haven’ maintained a higher growth, 

higher number of leaves and higher leaves water content than the other rootstocks studied and manifested 

less toxicity symptoms (necrosis, defoliation of leaves). However, in the same concentration, ‘C. Swingle 74.1’ 

and ‘C. B2.G3’ proved to be more performants respectively in regards to leaves chlorophyll and chloride 

contents. In general, the study suggested that the salt tolerance of the ten rootstocks can be classified in the 

following ascending order : ‘C. B2.G3’, ‘C. 4475 BB6A9’, ‘C. sacaton 30057’, ‘C. 57-98-506’, ‘C. 57-98-502’, ‘C. 

Swingle 74.1’, ‘C. Swingle F.9.22.5’, ‘C. 4475 AB6A4’, ‘C. Winter Haven B231431’, ‘Rangpur’ lime. 

S08P09 

Physiological response of Citrus macrophylla inoculated with arbuscular mycorrhizal fungi under 

salt stress 

Navarro J.M. 1 , Morte A. 2 , Rodríguez Morán M. 1 and Pérez-Tornero O. 1 

1 Instituto Murciano de Investigación y Desarrollo Agrario y Alimentario (IMIDA), Citriculture, Spain; and 2 Universidad de Murcia. 

Facultad de Biología Vegetal y Botánica, Spain. josefam.navarro2@carm.es 

Seedlings of Citrus macrophylla were inoculated with arbuscular mycorrhizal (AM) fungi, or left non-inoculated 

(-AM). Forty-five days after inoculation onwards, half of the AM and -AM plants were irrigated for three months 

with a nutrient solution containing 50 mM NaCl. Due to the high sensitivity of C. macrophylla to salinity, 

AM inoculation only partly compensates the growth limitations imposed by salinity. The high intercellular 

CO2 and the oxidative stress levels suffered by -AM plants decreased with AM inoculation. Although salinity 

strongly decreased photosynthesis in -AM plants, AM colonization alleviated this decrease in AM plants due 

to the higher total chlorophylls than in -AM. However, the chlorophyll and photosynthesis levels found in 

AM under salinity were still lower than in control treatments, so AM did not completely compensate for the 

negative effect of salinity on the photosynthetic response. Although AM significantly increased the water 

percentage in leaves, it did not modify the water potential in AM or -AM plants. Mycorrhizal inoculation 

increased the osmotic potential and consequently decreased turgor. However, this decrease did not affect 

the physiological processes that depend of leaf turgor such as photosynthesis, which even increased in AM 

plants. Given that, in the saline conditions used, AM plants had higher leaf Cl levels than -AM plants but 

showed better growth and a better physiological response, leaf Cl concentration was not related with salt 

tolerance in this experiment. 


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S08P10 

Cloning and functional analysis of stress-responsive genes in Poncirus trifoliata 

Liu J.H., Wang J., Huang X.S. and Sun P.P. 

Huazhong Agricultural University, College of Horticulture and Forestry Science, China. liujihong@mail.hzau.edu.cn 

Poncirus is a widely used rootstock for citrus because it has several desirable attributes, such as cold hardiness 

and Citrus Tristeza Virus tolerance. However, it is not drought and salt tolerant. On the other hand, most of 

citrus commercial cultivars are not cold tolerant. Therefore, it is necessary to obtain novel germplasms of 

either rootstock or scion cultivars with enhanced stress tolerance. As a complementation to the traditional 

breeding, genetic transformation has been proven as an effective approach to generate plants with enhanced 

stress tolerance. To make this new approach applicable to citrus cultivar improvement, it is obligatory to 

clone and functionally characterize genes involved in stress response. During the last years we have made 

efforts to isolate several functional or regulatory genes involved in stress response from trifoliate orange, 

including PtADC, PtrABF and PtrMAPK. Function of the genes in stress tolerance was characterized using 

Arabidopsis or tobacco transformation. For example, overexpression of PtADC in Arabidopsis led to enhanced 

tolerance to osmotic stress, drought and cold stress. Interestingly, transgenic plants exhibited longer roots 

and smaller stomatal density. Transformation of PtrAFB and PtrMAPK in tobacco resulted in elevated drought 

tolerance, accompanied by the induction of stress-responsive genes and enhanced antioxidant system for 

ROS scavenging. These genes hold great potential for genetic transformation in citrus or trifoliate orange. 

S08P11 

Characterization of water deficit tolerance of Poncirus trifoliata genotypes as related diversity 

Ben Yahmed J. 1 , Costantino G. 2 , Ben Mimoun M. 3 , Talon M. 4 , Ollitrault P. 1 , Morillon R. 1 and Luro F. 2 

1 Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), Amélioration des Plantes à 

Multiplication Végétative, France; 2 Institut National des Recherches Agronomiques (INRA), France; 3 Institut National Agronomique 

de Tunisie (INAT), Arboriculture Fruitiere, Tunisie; and 4 Centro de Genómica, Instituto Valenciano de Investigaciones Agrarias (IVIA), 

Spain. jihene.benyahmed@gmail.com 

Rootstock provides better adaptation to biotic and abiotic constraints. Poncirus and its hybrids are widely 

used since they are tolerant to Citrus Tristeza Virus. However, when grafted, most of them are considered 

to be sensitive to salinity and water deficit. Diversity does exist within the Poncirus trifoliata specie but 

little is known regarding the behaviour variability of genotypes to abiotic constraints. The citrus diversity 

of 72 P. trifoliata genotypes was investigated using SSR markers. Two mayor genetic groups were clearly 

identified. Five genotypes, belonging to each genetic group, were then selected to investigate their properties 

of tolerance to water deficit. Water deficit was applied by withdrawing irrigation for 4 weeks. Physiological 

parameters such leaf stomatal conductance and quantum yield of PSII electron transport, soil water potential, 

leaf osmotic pressure and transpiration were estimated. Among genotypes, we observed that some genotypes 

such as’ Rubidoux’ were clearly more tolerant to water deficit than others such as ‘Pomeroy’. Interestingly, 

the genotypes that were sensitive belonged to one genetic group and the tolerant ones belonged to the other 

group. Therefore, it sounds that among the Poncirus genus, it is possible to select genotypes as parent in 

breeding programs, which are more tolerant to water deficit. 

S08P12 

Screening nine citrumelo rootstocks for tolerance to drought conditions 

Fadli A. 1 , Beniken L. 2 , Omari F.E. 2 , Benkirane R. 1 and Benyahia H. 2 

1 Ibn Tofail University (IUT), Department of Plant Science, Kenitra, Morocco; and 2 Kenitra Regional Center for Argricultural Research 

(CRRAK), Department of Plant Breeding and Phylogenetic Ressources Conservation, Kenitra, Morocco. a.fadli.uit@gmail.com 

Two months old citrumelo rootstocks groups seedlings were grown in 0.5 L plastic pots in a greenhouse at El 

Menzeh (CRRA Kenitra), INRA Morocco, under three moisture regimes (100%, 75% and 50% Hfc) to investigate 

the effects of water stress on their morphological and physiological characteristics such as plant height, 

number of leaves per plant, fresh matter accumulation, transpiration ratio, chlorophyll content (SPAD), soluble 

solids and proline content, respectively. A split plot design with ten citrus rootstocks × three treatments and 


three replications was used. The measurements were taken at the end of the experiment. Growth parameters 

(plant height, number of leaves per plant, fresh matter accumulation), stomata conductance and chlorophyll 

content (SPAD) decreased under water deficit (50% Hcc). Increase in water stress increased the soluble 

solids and proline content. It is concluded that water stress significantly (p

S08 

S08P15 

Flooding and soil temperature affect photosynthesis of citrus rootstock leaves. 

Otero A. 1 , Goñi Altuna C.T. 2 and Syvertsen J.P. 3 

1 Instituto Nacional de Investigacion Agropecuaria (INIA), Ecophysiology Laboratory, Uruguay; 2 Instituto Nacional de Investigacion 

Agropecuaria (INIA), Soil and Plant Nutrition Laboratory, Uruguay; and 3 University of Florida. IFAS Citrus Research and Education 

Center (UF-IFAS), Citriculture, USA. aotero@sg.inia.org.uy 

We evaluated the effects of the soil temperature (15ºC, 25ºC and 35ºC) and soil anoxia from flooding for 

20 days on citrus rootstock seedlings of trifoliate (‘CT33’), ‘Carrizo’ citrange and ‘Troyer’ citrange along with 

‘Tucuman’, ‘Pomeroy’ and ‘Rubidoux’ trifoliates in a greenhouse. Flooding had no effect on shoot water 

potential (Ψs) and leaf relative water content (RWC) at 25ºC but at 15ºC and 35ºC, there were differences 

from non-flooded trees. ‘Carrizo’ and ‘Troyer’ had higher Ψs than ‘CT33’, and ‘Tucuman’ had the highest Ψs 

among the trifoliates. Soil temperature was more important than flooding in determining plant water status. 

In ‘Troyer’ at 25ºC, flooding decreased net assimilation of CO2 (ACO2) faster than in ‘Carrizo’ and ‘CT33’. 

At 35ºC, ACO2 was reduced up to 14% of non-flooded plants in only 4 days. ‘Tucuman’ had higher ACO2 

than ‘Rubidoux’ and ‘Pomeroy’. Higher values of internal CO2 concentration in leaves were associated with 

a reduction in maximum quantum efficiency (Fv/Fm) indicating that non-stomatal factors were more limiting 

to ACO2 than stomatal conductance at 25ºC and 35ºC, but not at 15ºC. In flooded plants, the decrease 

of Fv-Fm was highest at 35ºC. ‘Carrizo’ and ‘CT33’ maintained higher ACO2 at different soil temperatures 

but ‘Troyer’ had the lowest. Based on leaf net gas exchange, chlorophyll fluorescence and water relations, 

‘Troyer’ citrange was less tolerant to flooding than ‘Carrizo’ and’ CT33’ whereas ‘Tucuman’, ‘Pomeroy’ and 

‘Rubidoux’ had similar tolerance to anoxia regardless of temperature. 

S08P16 

Flooding affects fruitlet abscission in satsuma mandarin 

Goñi Altuna C.T. 1 , Otero A. 2 and Syvertsen J.P. 3 

1 Instituto Nacional de Investigacion Agropecuaria (INIA), Soil and Plant Nutrition Laboratory, Uruguay; 2 Instituto Nacional de 

Investigacion Agropecuaria (INIA), Ecophysiology Laboratory, Uruguay; and 3 University of Florida. IFAS Citrus Research and Education 

Center (UF-IFAS), Citriculture, USA. aotero@sg.inia.org.uy 

A field trial tested the effect of soil anoxia and flooding on fruit drop in a mature orchard of satsuma mandarin 

(Citrus unshiu) on ‘Pomeroy’ (Poncirus trifoliata) rootstock. Flooded trees were maintained with 10 cm water 

above the soil surface using a 60 cm high aluminum barrier which was buried to depth a 45 cm around the 

trees. Flooding lasted for 30 days, from flower anthesis to early fruit set. Waterlogging reduced the soil oxygen 

levels from 5 to 2 µg O 2 cm -2 min -1 . Relative fruit drop rate was higher in flooded trees than in non-flooded 

trees. Flooding reduced the spring flush shoot numbers but not the shoot length of the fewer shoots. Flooding 

reduced shoot water potential was but leaf chlorophyll was not affected. Flooding reduced net CO 2 assimilation 

rate (ACO2) and stomatal conductance but there were only small changes in internal CO 2 concentration in leaves 

and no changes in maximum quantum efficiency (Fv/Fm) or basal chlorophyll florescence (Fo). Thus, stomatal 

factors were more important than non-stomatal factors in limiting ACO2 in leaves of flooded trees. Proline was 

high in roots of flooded plants but not in leaves. Leaf starch was high in flooded trees however total reducing 

carbohydrates were unchanged. Low soil oxygen reduced root function and stomatal conductance and caused 

an accumulation leaf starch and early fruit drop. Soil anoxia from anthesis to early fruit set induced fruitlet 

abscission in satsuma mandarin and caused changes in tree water relations 

S08P17 

Frost damage in lemon orchards in the region of Murcia 

Conesa A. 1 , Martinez-Nicolas J. 2 , Manera J. 3 and Porras I. 2 

1 Miguel Hernandez University (UMH), Department of Vegetable Production and Microbiology, Spain; 2 Murcian Institute of Agriculture 

and Food Research and Development (IMIDA), Department of Citriculture, Spain; and 3 Miguel Hernandez University (UMH), 

Department of Physics and Architecture of Computers, Spain. agustin.conesa@umh.es 

Every few years frosts importantly affect the cultivation area surrounding the Region of Murcia (Spain). The 

most important frost period in recent years occurred at the winter of 1994-95 and the latest ones at 2004- 


05, 2010 -1 1 and 2011-2012. In this work we describe and compare the effects of the last two frost periods 

on fruit and vegetative damage in lemon trees varieties (Citrus limon) in the above mentioned area. During 

the 2010-2011 campaign, frost damage was more severe than in the current year 2011-2012. Temperatures 

in the citrus fields reached 6.63 °C with 10 hours of temperatures below 0 ºC. Frost-induced damage in fruits 

and vegetative tissue in orange and mandarin varieties were scarce whereas they were higher in grapefruit 

and severe in lemon trees, both in varieties grafted on Citrus macrophylla and on sour orange. Among lemon 

varieties studied, the most sensitive to frost turned out to be ‘Messina’. The risk of frost in the citrus area of 

Murcia for a critical temperature of -3 °C was also studied. The probability of frost damage is 2% on the coast 

and 60% in the inland valleys of Murcia. 

S08P18 

Physiological investigation of tolerance to iron chlorosis of ‘Navelina’ orange budded on different 

citrus rootstocks 

Çimen B., Yeşiloğlu T., İncesu M. and Yılmaz B. 

University of Cukurova (CU), Department of Horticulture, Turkey. bcimen@cu.edu.tr 

In this study, physiological responses of ‘Navelina’ orange grafted on eight different citrus rootstocks to 

iron deficiency were investigated under high pH conditions. ‘Navelina’ scion grafted on ‘Tuzcu 31-31’ sour 

orange, ‘Gou Tou’ sour orange, ‘Volkameriana’, ‘Antalya Cleopatra’ mandarin, ‘Carrizo’ citrange, ‘Troyer’ 

citrange, ‘C-35’ citrange and Poncirus trifoliata were grown in a plant growth chamber and irrigated with 

a modified Hoagland nutrient solution. In order to mimic an iron.deficient environment, 10 µM FeEDTA, 3 

mM NaHCO 3 and 2g/l CaCO 3 (pH=7.8) were added to the nutrient solution. Control plants were irrigated 

with a nutrient solution containing 100 µM FeEDTA (pH=6) for five months. At the end of the experiment, 

iron chlorosis color scale, leaf total and active Fe concentrations, Photosystem II efficiency (Fv’/Fm’), 

peroxidase and catalase activities were determined. In Fe-deprived leaves of ‘Navelina’ grafted on ‘C- 

35’ citrange and Poncirus trifoliata, total and active Fe concentrations and efficiency of PSII significantly 

decreased. These plants exhibited more severe Fe chlorosis symptoms than plants grafted on the rest of 

rootstocks. Young ‘Navelina’ trees grafted on ‘Tuzcu 31-31’ sour orange and ‘Gou Tou’ were less affected 

in terms of all parameters. As a result, ‘Navelina’ scions grafted on ‘Tuzcu 31-31’ and ‘Gou Tou’ sour 

oranges were the most tolerant; the ones grafted on ‘C-35’ citrange and Poncirus trifoliata were the most 

susceptible to iron deficiency. 

S08P19 

Differential tolerance to iron deficiency of citrus rootstocks grown in calcareous soil 

İncesu M., Yeşiloğlu T., Tuzcu Ö. and Çimen B. 

University of Cukurova (CU), Department of Horticulture, Turkey. meralincesu@gmail.com 

In this study, seedlings of 14 citrus genotypes used as rootstocks were tested in calcareous soil conditions 

(pH 7.8.) for their tolerance to lime-induced chlorosis in Adana-Turkey. The effect of iron deficiency on leaf 

active and total iron, leaf chlorophyll and leaf visual chlorosis were investigated. According to results of leaf 

chlorophyll and visual leaf chlorosis, ’Swingle’ citrumelo, ‘Pomeroy’ trifoliata and ‘Sarawak’ bintangor showed 

severe chlorosis on their leaves but these genotypes had the highest leaf total iron concentration (Fe paradox 

determined on these genotypes). At the end of the experiment, genotypes were classified in six categories: 

a) very tolerant: ‘Tuzcu 31-31’ sour orange, ‘Gou Tou’ sour orange, ‘Antalya Cleopatra’ mandarin and ‘Carrizo’ 

citrange; b) tolerant: ‘Tuzcu 891’ sour orange, ‘Volkameriana’,’ Nasnaran’ mandarin and ‘Marumi’ kumquat; 

c) moderately tolerant: hybrid of ‘Cleopatra’ mandarin and ‘Swingle’ citrumelo and ‘C-35’ citrange d) 

susceptible: ‘Swingle’ citrumelo and ‘Pomeroy’ trifoliata e) moderately susceptible: ‘Sarawak’ bintangor; and 

f) very susceptible: local Poncirus trifoliata. 


S08

S08 

S08P20 

Orange varieties as interstock in ‘Verna’ lemon trees increase the salt tolerance but not the 

drought or flooding tolerance 

Gimeno V. 1 , Simón I. 2 , Martínez V. 1 , Nieves M. 3 , Balal R.M. 4 and García-Sánchez F. 1 

1Centro de Edafología y Biología Aplicada del Segura (CEBAS), Plant Nutrition, Spain; 2Escuela Politécnica Superior de Orihuela (EPSO), 

Física y ATC, Spain; 3Escuela Politécnica Superior de Orihuela EPSO (EPSO), Agroquímica y Medio Ambiente, Spain; and 4University of 

Sargodha, Horticulture, Pakistan. fgs@cebas.csic.es 

We investigated the ability of interstocks to increase in abiotic stress tolerance in lemon trees with-threeindependent 

experiments. We compared 2-year-old ‘Verna’ lemon trees [Citrus limon; VL] grafted on sour 

orange (Citrus aurantium; SO) rootstock either without an interstock (VL/SO), or interstocked with ‘Valencia’ 

orange (Citrus sinensis; VL/V/SO), or with ‘Castellano’ orange (C. sinensis; VL/C/SO) in salinity, drought and 

flood conditions. In salinity experiment, trees were supplied with nutrient solutions containing 0, 30, or 60 

mM NaCl for two months. In drought experiment, half the trees were reduced by 25% watering every 5 days 

for 20 days. In flood experiment, half the trees were flooded for 9 days. The experiments were performed 

under greenhouse conditions. Leaf water relations, leaf gas exchange, chlorophyll fluorescence parameters, 

mineral nutrition, organic solutes, and carbohydrate concentrations were measured. Interstocked citrus 

trees are more salt-tolerant than noninterstocked trees. Leaf concentrations of Cl – and Na were higher in 

VL/SO trees than in VL/C/SO or L/V/SO trees, the mechanism involved in the reduction of leaf Cl – ions by an 

interstock could be linked to its low Eleaf values during the day and/or to their high S:R DW ratios.’ Valencia’ 

imparted greater salt-tolerance to VL trees than ‘Castellano’, even though leaf Cl – and Na levels were similar 

in the two interstocked trees. ‘Verna’ lemon trees interstocked with orange varieties did not improve the 

flooding and drought tolerance. Even, when ‘Valencia’ orange was used as the interstock, the flooding and 

drought tolerance was drastically reduced. 

S08P21 

Environmental effects on citrus growth and yield in the arid and semi-arid conditions of Kingdom 

of Saudi Arabia 

Aljaleel A. 1 , Ali-Dinar H. 2 and Noga G. 3 

1Najran Horticulture Research and Development Centre, Ministry of Agricuture, Kingdom of Saudi Arabia; 2FAO-UN, Riyadh, Kingdom 

of Saudi Arabia; and 3Institute of Horticultural Sciences, University of Bonn, Germany. bstanh@awalnet.net.sa 

The Kingdom of Saudi Arabia is situated in south west Asia between latitude 16 32 North and longitude 

35 65 East. The total area of the Kingdom is about 2.25 million square kms which represents about 80% 

of the area of the Arabian Peninsula. Most of the Kingdom’s regions are dominated by the arid and semiarid 

environmental conditions and irrigation is vital to cultivation and crop production. The Kingdom is 

characterized by a cropping system that is dominated over the years by date palm (Phoenix dactylifera) 

culture. However, in the early eighties, the cropping systems gradually changed to citrus cultivation in 

certain regions of the Kingdom, particularly Najran. These efforts were led by Najran Horticulture Research 

and Development Center (NHRDC) through which many citrus cultivars were introduced and evaluated. 

The performance of the different citrus cultivars was investigated over the years by (NHRDC). Differential 

observations were noticed on tree growth, flowering pattern and bloom intensity, fruit quality and yield 

and time of harvest. These differences were further substantiated by physiological parameters such as 

seasonal photosynthetic gas exchange. Grapefruit (Citrus paradisi), sweet orange (Citrus sinensis), lemon 

(Citrus limon), lime (Citrus aurantifolia) and tangerine (Citrus reticulata) genotypes have shown differential 

vegetative and reproductive growth due to seasonal environmental changes particularly, temperature and 

rain patterns. Vegetative and reproductive components of grapefruit and lime were less affected by these 

patterns. However, sweet orange and tangerine genotypes reflected noticeable differences, particularly on 

flowering patterns and bloom intensity and fruit juice nutritional aspects. The data are used to develop 

guidelines to citrus growers to adjust their cultural practices according to the environmental patterns to 

maximize yield and improve fruit quality. 


S08P22 

Micromorphological studies on the relation between fruit development and creasing in orange 

(Citrus sinensis cv. ‘Moro’ sanguine) 

Rajaei H. 

Shiraz University, Biology Department, Iran. hrajaei@susc.ac.ir 

Creasing is a preharvest physiological disorder which causes cracks in the albedo, resulting in the appearance 

of irregular grooves on the surface of the fruit. Albedo breakdown has been reported from many citrus growing 

areas worldwide, but not from Iran so far. This two years study has been performed on Citrus sinensis cv. ‘Moro’ 

sanguine in Mazandaran province, Northern Iran. Incidence and evolution of creasing were followed in 40 trees, 

at successive stages of development, from anthesis to fruit maturity. Morphological symptoms of creasing 

appeared at color break, first on the NE quadrant of all the trees and on the shaded side of each fruit. The disorder 

progressed towards other sectors along with the fruit development. Small pieces of rind in mature healthy and 

affected fruits were fixed with glutaraldehyde and osmium tetroxide, dehydrated in ethanol series and air dried, 

coated with gold-palladium, and viewed under the scanning electron microscope. First microscopic evidence 

of the disorder was observed in apparently healthy fruits, as a small hole or a thinning area, predominantly 

under the oil glands. Four progressive stages of creasing were recognized, based on SEM observations. The whole 

albedo cracked at the final stage, at the border line of the oil glands, and the exocarp was not affected by the 

disorder. Creasing seems to result from separation of albedo cells, rather than cleavage of individual cells. 

S08P23 

Behavior of diploid and tetraploid genotypes of ‘Carrizo’ citrange under abiotic stresses 

Ruiz M. 1 , Pina J. A. 1 , Alcayde E. 2 , Morillon R. 3 , Navarro L. 1 and Primo-Millo E. 2 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; 2 Instituto Valenciano 

de Investigaciones Agrarias (IVIA), Citricultura y Protección Vegetal, Spain; and 3 Centre de Coopération Internationale en Recherche 

Agronomique pour le Développement (CIRAD), UMR AGAP, France. ruiz_marval@gva.es 

Tetraploidy is a spontaneous phenomenon in citrus and some anatomical differences have been described 

between tetraploid (4x) citrus plants and their corresponding diploids (2x). The choice of a suitable rootstock 

is often very restricted by a combination of biotic and abiotic stresses. Recent data points out that tetraploidy 

in citrus induces interesting phenotypes like dwarfing and tolerance to abiotic constraints. In this work we 

investigated the behavior of 4x and 2x ‘Carrizo’ citrange (Citrus sinensis X Poncirus trifoliata) subjected to the 

main abiotic stresses that threat Spanish citrus industry. Seedlings were exposed to salinity, drought and iron 

deficiency and physiological parameters were measured. Results suggest that 4x plants stressed by drought 

were able to maintain high leaf water potential more efficiently than 2x, thus gas exchange parameters 

(transpiration, stomatal conductance, and photosynthesis) were less affected. Under salt stress no difference 

was found in leaf chloride content neither in gas exchange parameters, but leaf burn was less severe in 4x 

than in 2x. Concerning iron deficiency, a better tolerance of 4x compared to 2x was supported by higher ferricchelate 

reductase activity, SPAD index and chlorophyll fluorescence. These preliminary results suggest that 4x 

‘Carrizo’ citrange could be a promising rootstock, having the same general performance than the original 2x, 

but producing smaller trees more tolerant to abiotic stresses. 

S08P24 

Comparison of photosynthesis and antioxidant performance of several Citrus and Fortunella 

species under natural chilling stress 

Santini J. 1 , Giannettini J. 2 , Pailly O. 1 , Herbette S. 3 , Ollitrault P. 4 , Berti L. 2 and Luro F. 1 

1 Institut National de Recherche Agronomique (INRA), GEQA, France; 2 CNRS UMR 6134 (SPE), Laboratoire Biochimie et Biologie 

Moléculaire du Végétal, Corsica, France; 3 Institut National de Recherche Agronomique (INRA), UMR Physiologie Intégrée de l’Arbre 

Fruitier, France; and 4 Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), AGAP, 

France. santini4@univ-corse.fr 

Citrus plants originate from southeastern Asia, in a large area with various climates characterized by a broad 

range of temperatures. Temperature is assumed to be a key factor in Citrus species adaptation and diversification. 


S08

S08 

In a field experiment, the tolerance of the three fundamental Citrus species (C. medica –citron–, C. reticulata 

–mandarin– and C. maxima –pummelo–) and Fortunella japonica –kumquat– to photooxidative stress caused 

by seasonal climatic changes was evaluated on adult trees by measuring net photosynthesis (Pnet), stomatal 

conductance (Gs), maximum photosynthesis (Pmax) and chlorophyll fluorescence (Fv/Fm). In addition, seasonal 

changes in oxidative status, antioxidant enzymes and antioxidant metabolites were monitored. Mandarin 

and pummelo appeared to be the most tolerant, showing the lowest down-regulation of photosynthetic 

parameters, and the lowest accumulation of oxidized compounds associated with efficiency of their antioxidant 

system. Kumquat showed intermediate behaviour, with a large diminution of photosynthetic parameters and 

marked accumulation of hydrogen peroxide, whereas the malondialdehyde content remained low, with a 

strong induction of glutathione synthesis. Finally, citron appeared to be the most sensitive genotype with a 

marked decrease in photosynthetic performance, the largest accumulation of oxidative parameters, insufficient 

induction of antioxidant enzymes and down-regulation of ascorbate and glutathione synthesis. 

S08P25 

‘Flying Dragon’ as a very cold hardy citrus rootstock in Northern Iran 

Ebrahimi Y. 1 , Joshari H. 2 , Tavakoli A. 2 , Ghasemi S. 2 , and Rajabi A. 2 

1 Younes Citrus and Kiwi fruit Research and Propagation Station, Iran; and 2 Guilan Emdad Economical Complex, Iran. 

U_ebrahimi2000@yahoo.com 

Because of freeze damage to citrus orchards in Northern Iran, different citrus rootstocks were evaluated since 

1964 at the Ramsar Citrus Experimental Station. On request of Y. Ebrahimi, sixteen ‘Flying Dragon’ seeds were 

sent by Dr. Roose from Univ. of California Riverside to Ramsar, Iran in 1994. These sixteen seeds created the 

mother trees for ‘Flying Dragon’ seed production in Iran. Taking into consideration to grow citrus in Lakan area 

in Guilan province in 2006, the Agricultural Deputy of the Economical Group of Relief Committee (EGRE) of 

Iran established an experimental citrus pilot with 867 ‘Thompson’ navel oranges on ‘Flying Dragon’ rootstock 

in Lakan, Rasht (Guilan province). In January 2007, a very heavy snow fall followed by a destructive freeze 

(-14ºC) was occurred and confirmed the cold hardness of ‘Flying Dragon’ rootstock. This paper describes this 

very destructive frost and the results which were obtained. 


Session 09 

POSTHARVEST PHYSIOLOGY 

AND PATHOLOGY 

S09

S09O01 

Genome sequence of the necrotrophic fungus Penicillium digitatum, the main postharvest 

pathogen of citrus 

Ballester A.R. 1 , Marcet-Houben M. 2 , de la Fuente B. 1 , Harries E. 1 , Marcos J.F. 1 , Gabaldón T. 2 , and González-Candelas L. 1 

1 Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Food Science, Spain; and 2 Center for Genomic Regulation (CRG-UPF), 

Comparative Genomics, Spain. lgonzalez@iata.csic.es 

Penicillium digitatum is a fungal necrotroph causing Green Mold in citrus fruit during postharvest storage. Despite 

its economic importance, the genetic bases of its virulence mechanisms and its high host-specificity remain 

unknown. Here we present the genomes of two P. digitatum strains that differ in their antifungal resistance 

traits, and their comparison with 28 other Pezizomycotina. The two sequenced genomes are highly similar, 

yet important differences include the presence, in the resistant strain, of a unique gene cluster, and mutations 

previously shown to confer fungicide resistance. The two strains and one isolated in China have identical 

mitochondrial genome sequences, suggesting a recent worldwide expansion of the species. Comparison 

with the closely-related but non-phytopathogenic P. chrysogenum, reveals a much smaller gene content in P. 

digitatum, consistent with a more specialized lifestyle. Large regions in P. chrysogenum genome, including entire 

super-contigs, are absent in P. digitatum, probably as the result of large gene family expansions, rather than 

acquisition through horizontal gene transfer. Our analysis of P. digitatum genome suggests a heterothallic sexual 

reproduction and reveals the molecular bases behind the inability of this species to assimilate nitrate or to 

produce the metabolites patulin and penicillin. Finally, we identify the predicted secretome, which provides a 

first approximation to the protein repertoire used during invasive growth. 

S09O02 

RNA-Seq analysis of yeast antagonist Metschnikowia fructicola during interactions with 

Penicillium digitatum and grapefruit peel reveals specific transcriptional responses 

Hershkovitz V. 1 , Sela N. 2 , Taha L. 3 , Rafael G. 1 , BenDayan C. 1 , Feygenberg O. 1 , Aly R. 3 , Wisniewski M. 4 , and Droby S. 1 

1 The Volcani Center (ARO), Institute of Postharvest and Food Science, Israel; 2 The Volcani Center (ARO), Department of Plant pathology 

and weed research, Israel; 3 The Volcani Center, Newe-Yaar Research Center, Department of Plant Pathology and Weed Research, ; 

and 4 U.S. Department of Agriculture-Agricultural Research Service (USDA-ARS), Appalachian Fruit Research Station, USA.vhershko@ 

agri.gov.il 

The yeast Metschnikowia fructicola is a biological control agent with broad activity against various postharvest 

diseases of several fruits. Information about the yeast antagonist mode of action still lacking and largely 

rely on non-direct evidence. In this study, we performed transcriptome analysis on M. fructicola following 

its interaction with the host (grapefruit) and the pathogen (Penicillium digitatum) using next-generation 

sequencing technology for RNA (RNA-Seq). We obtained more than 26 million sequencing reads that 

were then assembled into 9674 unigenes and half of these genes had an annotation with matches in the 

NCBI database. Assembled sequences were annotated with gene description, gene ontology and clusters 

of functional group terms. Differential expression analysis revealed more than 250 genes with specific 

expression responses. In the antagonist-pathogen, genes related to transmembrane multidrug transport 

and to amino acid metabolism were induced. In antagonist-fruit interaction, expression of genes involved in 

oxidative stress, iron homeostasis, zinc homeostasis and lipid metabolism were enhanced. We investigated 

the gene expression patterns at the transcript levels in the two types of interactions by quantitative real-time 

PCR analysis. The data revealed that genes encoding hydrolytic enzymes glucanase (GLU) and chitinase (CHI), 

superoxide dismutase (SOD1) and signal transducing MEK kinase (MEKK) had specific expression pattern. Our 

results provide new insight into the biology of interaction between host-antagonist-pathogen interactions. 

S09O03 

The mitogen-activated protein kinase PdSLT2 of Penicillium digitatum is required for fungal 

pathogenesis/virulence during citrus infection. 

de Ramón-Carbonell M., and Sánchez-Torres P. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Departamento de Protección Vegetal y Biotecnología, Spain. palomas@ivia.es 

Postharvest decay accounts for the most significant losses of postharvest citrus worldwide. Green Mold caused 

by Penicillium digitatum is the major responsible of the postharvest decay of citrus in Mediterranean regions. 


S09

S09 

Nevertheless our knowledge on its pathogenicity/virulence mechanisms is still very limited. The mitogenactivated 

protein kinase (MAPK) cascade is involved in the transduction of a variety of extracellular signals and 

the regulation of several developmental processes. In most filamentous fungi, SLT2 MAPK family is involved in 

the cell integrity pathway and in many cases is essential for full virulence since it is implicated in sporulation, 

surface sensing of germ tubes, host penetration and lesion formation. In this work Penicillium digitatum 

SLT2 homologous gene PdSLT2 have been identified and characterized. Analysis of its role in pathogenesis/ 

virulence was carried out through the generation of gene knock-out mutants with Agrobaterium tumefaciens 

mediated transformation (ATMT) and evaluating infection capacity. Expression analysis was conducted by 

qRT-PCR. Gene expression was determined in orange fruits during P. digitatum infection, and during growth 

of P. digitatum in culture medium PDB of both wild type and null mutants. To our knowledge this is the first 

MAPK identified in P. digitatum and in this work we confirm that PdSLT2 is involved in fungal virulence and 

the expression patterns of several genes in null mutants revealed which genes are transcriptional regulated 

by PdSLT2. 

S09O04 

Function of PdCrz1, a calcineurin-responsive transcription factor, in Penicillium digitatum in 

conidiation, virulence and responses to abiotic stresses 

Zhang T., and Li H.Y. 

Institute of Biotechnology, Zhejiang University, China. hyli@zju.edu.cn 

Calcineurin-responsive zinc finger transcription factor Crz1 regulates many genes involved in fungus growth, 

morphogenesis, responses to stresses, resistance to drugs and pathogenicity in their hosts. In the present 

study, we characterized an ortholog of Crz1, PdCrz1, in P. digitatum, the most important pathogen of 

postharvest citrus. PdCrz1 encodes a protein that shares a high amino acid sequence similarity with Crz1 in 

Aspergillus spp. To determine the function(s) of PdCrz1, a gene-disruption mutant was generated using an 

Agrobacterium tumefaciens-mediated transformation procedure (ATMT). The PdCrz1 disruption (ΔPdCrz1) 

mutant was defective in conidiation, cell wall integrity, and virulence, and is hypersensitivity to stresses 

caused by Ca 2 , H 2 O 2 and azole fungicides. Expression of cell wall synthase genes (CHS2, CHS3 and FKS1), 

P-type ATPases genes (PMR1 and PMC1) was significantly reduced in the PdCrz1 mutant compared with the 

wild type P. digitatum. Calcineurin inhibitors were shown to enhance the effect of imazalil on P. digitatum. 

In contrast, activation of the Ca 2 /calmodulin-dependent pathway by Ca 2 alleviated the antifungal activity by 

imazalil. These results indicate that PdCrz1 plays important roles in P. digitatum conidation, pathogenicity 

and membrane lipid homeostasis. In addition, the study also indicates a synergistic fungicidal activity on 

P. digitatum between calcineurin inhibitors and DMI fungicides, implying that specific inhibitors of calcium 

signalling pathway could be potentially developed as useful adjuvants of conventional DMIs for the control 

of fungal diseases. 

S09O05 

The Protein O-Mannosyltransferase PMT2 of the citrus-specific postharvest pathogen Penicillium 

digitatum is involved in conidiogenesis, virulence and sensitivity to the antifungal peptide PAF26 

Harries E., Gandía M., Carmona L., and Marcos J.F. 

Instituto de Agroquímica y Tecnología de Alimentos (IATA), Food Science, Spain. jmarcos@iata.csic.es 

Our group has demonstrated that genes encoding Protein O-Mannosyl Transferases (PMT) determine the 

sensitivity of the yeast Saccharomyces cerevisiae to the short antifungal hexapeptide PAF26. In previous 

studies, we had identified the family of PMT genes in the citrus fruit postharvest pathogen Penicillium digitatum 

and showed their expression during axenic growth and fruit infection. To study functional significance, 

Agrobacterium-mediated transformation (ATMT) was used to: (i) disrupt PdigPMT2, and (ii) overexpress it 

under control of the A. nidulans gpdA promoter. The mutant Δpmt2 displayed slow rate of growth and a strong 

reduction of conidia production. Interestingly, the growth of Δpmt2 was recovered with osmotic stabilization, 

while conidiation was only partially restored. Microscopy observation showed balloon-like swollen cells and 

defects in conidiophore formation in the Δpmt2 mycelium. The mutant also showed increased sensitivity to 


calcofluor white (CFW) or congo red (CR), but remarkably resistance to reactive oxygen species (ROS). Conidia 

of the mutant were also resistant to the fungicidal activity of PAF26, confirming that protein glycosylation 

also determines the sensitivity to antimicrobial peptides in filamentous fungi. None of the overexpressors 

displayed variations in susceptibility against the antifungal compounds analyzed. In bioassays of controlled 

inoculation, we confirmed that PMT2 is required for full virulence of P. digitatum to citrus fruit. 

S09O06 

PdCYP51B, a new sterol 14α-demethylase gene of Penicillium digitatum involved in resistance to 

imazalil and other fungicides inhibiting ergosterol synthesis 

Sun X.P., Wang J.Y., Feng D., and Li H.Y. 

Institute of Biotechnology, Zhejiang University, China. hyli@zju.edu.cn 

The phenotypes and genotypes of 403 isolates of Penicillium digitatum, collected from packing houses and 

supermarkets in Zhejiang, China, during 2000 to 2010, were characterized in terms of their imazalil sensitivity. 

The frequency of detected imazalil-resistant (IMZ-R) isolates increased from 2.1% in 2000 to 60–84% during 

2005–2010. Only 6.5% and 4.5% of the collected IMZ-R isolates belong to the previously described IMZ-R1 

and IMZ-R2 genotypes, respectively. A homolog (PdCYP51B) of PdCYP51, which encodes the target of imazalil, 

was revealed from genomic database of P. digitatum. Sequence analysis of PdCYP51B from six IMZ-R3 and 

eight imazalil-sensitive (IMZ-S) isolates indicated that a unique 199-bp insertion was presented in the 

promoter region of PdCYP51B in all IMZ-R3 isolates but absent in all IMZ-S isolates. Transcription levels of 

PdCYP51B in IMZ-R3 isolates were 7.5- to 13.6-fold higher than that in two IMZ-S isolates. Introduction of 

another copy of PdCYP51Bs (from IMZ-S) into an IMZ-S isolate increased the resistance of P. digitatum to 

demethylase inhibitors (DMIs) only to a small extent, but introduction of a copy of PdCYP51BR (from IMZ-R3) 

dramatically increased the resistance level of P. digitatum to DMIs. Based on these results, we concluded 

that (1) the CYP51 family of P. digitatum contains another member PdCYP51B, in addition to the known gene 

PdCYP51A (previously PdCYP51); (2) PdCYP51B is involved in DMI fungicide resistance; and (3) overexpression 

of PdCYP51B resulting from a 199-bp insertion mutation in the promoter region of PdCYP51B is responsible 

for the IMZ-R3 type of DMI resistance in P. digitatum. 

S09O07 

Current and emerging strategies for Sour Rot management of citrus in Australia 

Taverner P.D., and Cunningham N.M. 

South Australian Research and Development Institute (SARDI), Sustainable Systems, Australia. Peter.Taverner@sa.gov.au 

In Australia, Green Mould (Penicillium digitatum) and Blue Mould (P. italicum) are serious diseases affecting 

citrus fruits. Sour Rot (Geotrichum citri-aurantii) is sporadic but control options are more limited. Sour Rot, or 

rather a complex of Sour Rot with Mould, is an intractable problem for Australian citrus exports. Researchers 

work closely with citrus packers to integrate control measures for sour rot into existing treatments for mould 

control. This usually involves combining chemical fungicides with sanitisers &/or generally regarded as safe 

compounds (GRAS). Careful evaluation is necessary because chemical mixtures can be neutral, additive, 

synergistic or antagonistic. Generally, research adheres to two main aims; sour rot spore control in water 

suspensions, and sour rot control on fruit. The first approach uses sanitisers in water washes and fungicide 

applications. Sanitisers added to fungicide dips can reduce sour rot spore loads but chemical incompatibility 

is common. The response varies with sanitiser active, fungicide active and fungicide formulation. The second 

approach aims to enhance sour rot control on fruit by combining fungicides and GRAS compounds. Various 

mineral and organic salts have demonstrated enhance sour rot control. Sanitising these mixed solutions is 

problematic, with the choice of fungicide, salt and sanitiser influencing compatibility and efficacy. Increased 

worldwide concern in Sour Rot has lead to productive research, which may lead to new approaches for 

control of this disease. The studies used to develop current strategies and possible future research directions 

are discussed. 


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S09O08 

A new prespective in controlling postharvest citrus rots 

Fallanaj F., Sanzani S.M., and Ippolito A. 

Department of Soil, Plant and Food Science, Univeristy of Bari ‘Aldo Moro’, Italy. fridafallani@yahoo.it 

The need for alternative control means to reduce postharvest decay of fruits is becoming increasingly 

important. Frequently, contaminations take place in the postharvest environment e.g. in the wash water. 

Several sanitizers have been studied for their effectiveness in the inactivation of this pathogenic microflora, 

however their limited efficacy or drawbacks prevented their practical use. The electrolyzed water represents a 

major step forward, as an effective and economical alternative. EW has been shown to have broad-spectrum 

antimicrobial activity in inactivating a variety of bacteria of public health significance, which might affect 

minimally-processed vegetables. Recent studies have also shown a certain efficacy of EW against postharvest 

rots on peaches, pears, grapes, and citrus fruits. However, they rely on the electrolysis of NaCl solutions, thus 

not avoiding the formation of chlorine by-products which may represent a limitation. The present study was 

carried out to evaluate the effectiveness of EW in controlling citrus rots during processing in the packinghouse 

environment. We focused on developing an effective protocol for practical application during postharvest 

handling of citrus, which does not require the use of chlorine salts. Our results showed that once the machine 

parameters and water composition are carefully analyzed and set up, EW may be effective in prolonging the 

shelf life of citrus fruit during storage, although its potential needs to be further investigated. 

S09O09 

Global solution for preserving citrus fruit using natural treatments 

Conesa E. 

Fomesa Fruitech (FOMESA), Technical Department, Spain. econesa.fruitech@fomesa.net 

Different tests were carried out in conjunction with the IVIA’s Post-Harvest Technology Centre to assess the 

efficiency of natural treatments replacing standard phytosanitary treatments. First, the efficiency of an aqueous 

treatment containing a food preservative was assessed. This system significantly reduced the appearance of 

decay in ‘Marisol’ mandarins inoculated with 10 5 spores/mL of Penicillium digitatum and P. italicum. The same 

food preservative was used in conjunction with a detergent on ‘Washington Navel’ sweet orange fruit previously 

inoculated with the same mix of P. digitatum and P. italicum. The reduction in decay was similar to that obtained 

using guazatine as reference. Finally, two different natural products were tested. One was combined with a 

natural coating and the food additive, whilst the other was applied as a fumigant. The results of the these two 

assays showed a significant reduction of decay in ‘Clemenules’ mandarins and ‘Valencia-Late’ sweet orange 

fruit, respectively, which were both previously inoculated with P. digitatum and P. italicum. In summary, different 

treatments have been assessed which significantly prevented decay in citrus fruit inoculated with Penicillium 

spp. These treatments can be considered as a viable alternative to the use of phytosanitary products. 

S09O10 

Could ethylene influence Peteca Spot incidence of lemon fruit? 

Cronjé P.J.R. 

Citrus Research International (CRI), South Africa. paulcronje@sun.ac.za 

Peteca Spot (PS) of lemon is a postharvest physiological disorder resulting in the collapse of the oil gland. 

Subsequently, the oil leaks into the adjacent tissue and causes a darkened depression. The occurrence can 

be severe, without any specific pre- or postharvest practices to avoid reduce the incidence. PS occurs in all 

citrus production areas of South Africa and is thought to be the result of the immature rind being subjected to 

postharvest stress associated with high CO 2 concentration in degreening, as well as the physical impact of the 

packing line and wax application. Over several seasons the incidence of PS was investigated to identify factors 

that influence the incidence of the disorder. The first observation was the highly erratic incidence between 

seasons as well as within an orchard in a season, with the early fruit being highly susceptible. In experiments 

to identify postharvest factors which influence the PS incidence, 3 ppm ethylene and 1% CO 2 were applied in 


a continuous flow-through system (20°C for 3 d). The CO 2 treatment resulted in significantly higher incidence 

compared to the rest. Following on from these results, postharvest ethephon (2-chloroethyl phosphoric 

acid) (200 mg/L and 400mg/L) and AVG (aminoethoxy-vinylglycine) (400 mg/L and 800 mg/L) applications to 

fruit resulted in a significant reduction in PS. In the subsequent season, the same treatments were applied 

in an orchard one week before harvest and a similar reduction in PS was recorded. Ethylene production 

from these fruit after harvest was measured and showed a transient spike in fruit from the Ethephon and 

AVG treatments. The results collected over several seasons could indicate a protective action of ethylene in 

reducing rind sensitivity to PS. It is hypothesised that if the internal ethylene synthesis is increased prior to 

harvest in sensitive fruit, i.e. immature fruit, a reduction in PS can occur. 

S09O11 

Tahiti lime post-harvest evaluation and non-destructive assessment of essential oils by NIR 

spectroscopy 

Diaz-Candelas C.C. 1 , Morales-Payán J.P. 1 , and Romañach R. 2 

1 Universidad de Puerto Rico, Recinto Universitario de Mayaguez (UPR-Mayaguez), Crops and Agroenvironmental Sciences, Puerto 

Rico; and 2 Universidad de Puerto Rico, Recinto Universitario de Mayaguez (UPR-Mayaguez), Chemistry, Puerto Rico. 

cecilia.diaz1@upr.edu 

Near Infrared spectroscopy (NIRS) has been used as a non-destructive, real time analysis method to evaluate 

the terpene content in the essential oils in citrus fruits. The C-H stretch bands confirmed the presence of 

terpenes in Tahiti lime flavedos analyzed directly without solvent extractions. This method was utilized to 

evaluate whether biorregulators affect the content of terpenes in the flavedo. A Tahiti lime orchard located at 

Lajas, Puerto Rico was submitted to seven independent treatments of biorregulators to evaluate their effect 

in fruit abscission, post-harvest life and terpene content. The solutions consisted of aminoethoxyvinylglycine 

(AVG), a sea weed emulsion with a 0.01% kinetin content (Kn), a shark emulsion (H), a fertilizer containing 

tocopherol and brassinolide (T Br), GA3, GA4&7, and a mixed solution of these GA’s. NIR spectrums were 

taken within three days of harvest. Post-harvest quality trait changes were observed during eight weeks 

to fruits stored at 10 ºC and 85% RH. The GA3 treatment yielded smaller fruits that took longer to change 

their green color. AVG treatments yielded fruits with higher juice content followed by GA4&7 and the mixed 

GA’s. AVG and Kn treated trees had less abscission and yielded the most fruits for six weeks after which Kn 

continued this low abscission rate. With NIRS it was possible to differentiate between flavedo, albedo and pulp 

and to correlate intense peaks of the flavedo spectra with three terpenes. Results strongly suggest a directly 

proportional relation between terpene content and fruit maturity. A calibration model is in development. 

S09O12 

Postharvest blue light treatments affect citrus fruit susceptibility to disease by altering oxylipin 

biosynthesis 

Alférez F. 1 , Liao H.L. 2 , and Burns J.K. 2 

1 Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Laboratorio de Fisiología Y Biotecnología Postcosecha, Spain; 2 Citrus 

Research and Education Center-University of Florida (CREC-UF), Horticultural Sciences, USA. alferez@iata.csic.es 

The effect of blue light on infection by different postharvest pathogens was investigated in tangerines and 

sweet oranges during postharvest. Exposure of fruit to 410-540 nm blue light at a fluency of 40 μmol m-2s-1 

reduced symptom development of Blue Mold (Penicillium italicum), Green Mold (P. digitatum), and Stem End 

Rot (Diaporthe citri) postharvest decays. However, blue light also reduced in vitro fungal growth of P. italicum 

and D. citri and activity of fungal polygalacturonase. Blue light treatment induced phospholipase A2 (PLA2) 

gene expression in ‘Fallglo’ tangerines. Inhibition of PLA2 activity allowed infection, whereas inhibition of 

phospholipase D (PLD) expression by 580-670 nm red light was correlated with infection. These data suggested 

induction by blue light of the oxylipin pathway. Gas chromatography-mass spectrometry analysis of flavedo 

oil showed that blue light induced accumulation of the C8 oxylipin octanal. Application of octanal suppressed 

growth of P. italicum, P. digitatum, and D. citri in vitro. Treatment of fruit with octanal suppressed symptom 

development caused by Penicillium and D. citri. The effect of blue light on citrus decay could be due to its impact 

on fungal growth and development, and the induction of fruit response via oxylipin synthesis in the peel. 


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S09O13 

Potassium sorbate increases citrus weight loss in postharvest treatments but it does not provide 

good decay control in wax 

Parra J.P. 

Postharvest Technology, Spain. encarna@citrosol.com 

Potassium sorbate (PS) is a well-known and widely used food preservative. Among other applications, it 

is used as a GRAS fungistatic postharvest treatment for citrus. We studied the efficacy of wax containing 

increasing concentrations of PS on decay control of Penicillium digitatum, and its effect on fruit weight loss. 

Decay control and weight loss increased with the concentration of PS in wax. Wax with typical amount of 

2–5% PS showed poor decay reduction indices (around 20%), whereas fruit weight loss increased compared 

with non-waxed control. Waxing the fruit reduced weight loss by 25%, but the addition of just 2% PS to the 

wax caused an increase in fruit weight loss of almost 40% compared with waxed fruit. The hygroscopic effects 

of PS are more damaging for citrus fruits with leaves. Leaves weight loss was very rapid when PS was added 

to the wax, becoming desiccated in 24 hours, old and brittle. This issue is very important for the fresh packer 

because these fruits are sold with leaves as proof of their freshness. Results of a similar study where PS 

was applied to citrus as an aqueous treatment will be also presented. When applied in water, PS was more 

effective for decay control than when applied in wax, but there was a considerable increase in fruit weight 

loss. Combining aqueous PS with our Fortisol® Ca Plus phytofortifier completely solved the problem of weight 

loss and achieved outstanding decay control, making these mixtures as promising treatments. 

S09P01 

Transcriptional regulation of the Citrus sinensis ABA-signalosome during fruit dehydration 

Romero P., Rodrigo M.J., and Lafuente M.T. 

Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Food Science. Postharvest Physiology and Biotechnology, Spain. 

mtlafuente@iata.csic.es 

Water stress is an important factor affecting fruit quality. Since abscisic acid (ABA) is a key regulator of the dehydration 

response, understanding how the hormone is perceived will help to identify targets to improve drought hardiness 

in horticultural crops. To study the involvement of the ABA perception system in the dehydration response of 

citrus fruit, we have performed a comparative transcriptional analysis of the ABA-signalosome components in 

water-stressed fruit of ‘Navelate’ orange (Citrus sinensis) and its fruit-specific ABA-deficient mutant ‘Pinalate’, 

which is more prone to dehydration. No significant differences in the absolute expression levels of ABA receptors 

(CsPYR/PYL/RCAR) were found between wild-type and mutant fruit, while those of the negative regulators 

(CsPP2CA) were slightly lower in the mutant. Low differences in ABA receptors and downstream protein kinases 

(CsSnRK2) transcripts levels were found in response to dehydration. Contrary, CsPP2CAs gene expression was 

highly regulated by ABA content and showed differences between cultivars, which suggest that CsPP2CAs play a 

key role regulating ABA response in citrus fruit to water stress. Results obtained by ABA application indicate that 

although the mutant may sense ABA, the hormone signal could be impaired because of reduced CsPP2CAs levels. 

Overall results highlight these components as potential targets to improve drought hardiness in citrus fruits. 

S09P02 

Delayed color break in ‘Tardivo’, a late ripening mandarin mutant, is related to a defective 

ethylene response 

Alos E. 1 , Distefano G. 2 , Rodrigo M.J. 1 , Gentile A. 2 , and Zacarias L. 1 

1 Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Food Science, Spain; and 2 University of Catania, Dipartamento di 

Scienze delle Produzioni Agrarie e Alimentari, Italy. lzacarias@iata.csic.es 

Late ripening mutants, with delayed peel color changes and senescence, are of paramount importance for the 

citrus industry because they allow an extended harvesting and marketing period. Hence, the characterization 

of these mutants constitutes a useful system to decipher the molecular bases that regulate the timing and 

rate of color development in citrus fruits. Although the causes for these phenotypes may be diverse, recent 


experimental evidences in mandarin fruit link delayed degreening with differential ethylene sensitivity. 

‘Tardivo’ is a late ripening mutant of clementine mandarin that displays a certain inability to ethylene induceddegreening. 

In the present work, we have explored if this phenotype is associated with differential responses 

to ethylene-regulated gene expression. To this end we have analyzed the expression of key genes involved 

in carotenoid, ABA and phenylpropanoids biosynthesis and also in the ethylene biosynthetic and signaling 

pathways. Results indicate an altered ethylene-induced gene expression in ‘Tardivo’ fruits, displaying a 

transient response to ethylene that is unable to sustain it subsequently. 

S09P03 

Comparative proteome and metabolome profiling analysis heat treatment induced fruit 

resistibility during postharvest storage 

Yun Z., Liu P., Liu S.Z., Luo T., Jin S., Gao H.J., Xu Q., Xu J., Cheng Y.J., and Deng X.X. 

Key Laboratory of Horticultural Plant Biology of Ministry of Education, Huazhong Agricultural University, China. 

yjcheng@mail.hzau.edu.cn 

From harvest to human consumption, the commercial production of fresh fruits requires time for shipping, 

storage and marketing. During these processes, physiological disorders and pathological diseases are the main 

causes of fruit loss. Heat treatment (HT) has been widely used to maintain fruit quality during postharvest 

storage. However, little information is available related to the underlying mechanisms occurring during 

storage at a systemic biological level. ‘Kamei’ Satsuma mandarin (Citrus unshiu) fruits were selected for use in 

exploring the mechanisms induced by HT which allow fruit to resist such damage during postharvest storage. 

Proteome and metabolome studies were conducted based on two-dimensional gel electrophoresis (2-DE), gas 

chromatography coupled to mass spectrometry (GC-MS), and liquid chromatography/electrospray ionisation 

time-of-flight mass spectrometry (LC/QTOF-MS). The results showed resistance associated proteins were upregulated, 

such as beta-1, 3-glucanase, Class III chitinase, 17.7 kDa heat shock protein and low molecular 

weight heat-shock protein. This study provides new insights into HT induced fruit resistance to pathogens and 

physiological disorders. Interpretation of the data for the proteins and metabolites revealed reactive oxygen 

species (ROS) play an important role in HT induced fruit disease and stress resistance. Redox metabolism 

proteins were down-regulated in HT fruits while the intracellular H2O2 content decreased in HT fruits, which 

might increase fruit resistibility in response to external stress. Also, flavonoids were up-regulated in HT fruits, 

a process which was directly involved in the response to external stress. Moreover, the H2O2 in the fruit was 

used to synthesize lignin, which leads to increased lignin content in HT fruits. The increased lignin-induced 

thickening of cell walls was involved in isolating external pathogens from fruits. 

S09P04 

Postharvest water stress leading to peel disorders in citrus fruit involves regulation of 

phospholipases by ABA 

Romero P., Gandia M., and Alférez F. 

Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Laboratorio De Fisiología y Biotecnología Postcosecha, Spain. 

alferez@iata.csic.es 

The interplay between abscisic acid (ABA) and phospholipases A2 and D (PLA2 and PLD) in the response 

of citrus fruit to water stress was investigated during postharvest by using an ABA-deficient mutant from 

‘Navelate’ sweet orange. Fruit from both varieties were subjected to prolonged water stress conditions 

inducing non-chilling peel pitting in the rind. Treatment with phospholipase inhibitors reduced the disorder in 

both varieties suggesting that phospholipid metabolism is involved in citrus peel quality. Expression of genes 

encoding PLA2 and PLD was studied by real time RT-PCR during water stress and in response to ABA. Expression 

of CsPLA2α was dependant on ABA in fruit from both varieties, since ABA application restored expression in 

the mutant, showing for the first time the involvement of this hormone in the activation of PLA2. CsPLDα 

expression increased with dehydration in mature-green fruit from ‘Navelate’ but not in the mutant and ABA 

did not counteract this effect, suggesting that ABA deficiency in the mutant impairs sensitivity. Our results 

show interplay between PLA2 and PLD substrates and products, and suggest that ABA action is upstream 

phospholipase activation in response to water stress. 


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S09P05 

Quality attributes of Valencia orange (Citrus sinensis) fruit coated with different edible covers 

Mohammadi-Shamloo M. 1 , Sharifani M.M. 2 , Daraei-Garmakhany A. 2 , and Seifi E. 3 

1 Gorgan University of Agricultural sciences, Horticulture, Iran; 2 Gorgan University of Agricultural Sciences and Natural Resources, 

Horticulture, Iran; and 3 Gorgan University of Agricultural Sciences and Natural Resources, Food Science and Technology, Iran. 

mmsharif2@gmail.com 

This study was aimed to determine the best treatment to control fruit rot, quality preservation and increase 

in storage life of ‘Valencia’ sweet orange. Fruits were treated with clove oil using (1%), edible wax, mixture of 

clove oil with wax and control. Treated fruits were stored (7°C and 85% RH) and several quality attributes such 

as fruit peel firmness, weight losses, rate of infection by rot agent, TSS, pH, TA, vitamin C and all related sugars 

were measured every three weeks. The data were analyzed using a factorial statistical design in a frame of 

RCD using SAS software. According to the results, none of the treatments had significant effect on pH, TA 

and TSS (%). Vitamin C content (mg/100g) indicated an increasing trend until 42 days of storage and then a 

decreasing trend was appeared. The cover types had no significant effect on vitamin C content. The highest 

water loss was observed in the control, even though different treatments could diminish the water loss. 

However, none of these treatments caused significant differences. Fruit firmness and rot value differences 

were significant. Clove oil could inhibit growth of any rot agent. The cover types had significant impact on the 

available glucose in the orange juice. The mixture of wax and clove oil provided highest glucose (mg/100g) 

remaining in the edible tissue (P

for 14 days was investigated. Changes in sugar content were negligible at the different temperatures. Organic 

acids decreased slightly at all temperatures, with the exception of malic acid at 30°C, which increased slightly. 

For 13 amino acids, postharvest changes differed between low and high temperatures. Ornithine and glutamine 

increased at 5°C but not at other temperatures. The concentration of 11 amino acids (isoleucine, leucine, valine, 

threonine, lysine, methionine, phenylalanine, tryptophan, tyrosine, histidine, and γ-amino butyric acid) was higher 

at 20 and 30°C than at other temperatures. Thus, the content of amino acids was more variable in response to 

the storage temperature than that of sugars and organic acids. Moreover, changes in amino acids by temperature 

differed among species, 2 cold-responsive and 11 heat-responsive. Results indicated that 10°C was the optimal 

temperature to minimize postharvest changes in metabolite profiling in the juice sacs of Satsuma mandarin fruit. 

S09P08 

Stem End Rind Breakdown of citrus fruit a new postharvest physiological disorder of lemon fruit 

in tucuman (Argentina) 

Torres-Leal G.J., Velazquez P.D., Carbajo M.S., Farias M.F., and Pedraza J.R. 

Instituto Nacional de Tecnología Agropecuaria (INTA-Famaillá), Frutihorticulture, Argentina. gtleal@correo.inta.gov.ar 

Lemons from packinghouses destined for exportation of the season 2008 to 2012 were surveyed. Fruits 

of lemon from Santa Lucia and Yacuchina (Monteros–Tucuman) exhibited unusual symptoms consisting in 

sunken brown spot around the stem of rind and later became dark during the packing process. The objective 

of this work was to determine the causal factor of this disorder. Affected tissues were collected and streaked 

onto PDA to identify possible causal fungal pathogens. Meteorological data were analyzed from 2008 to 2012 

of study area. No pathogens were isolated. Rain and relative humidity during the months previous to harvest 

(March to April) were lower and temperature higher than the average values over the last 45 years. Based 

on symptoms and information from other citrus-growing areas of the world, a physiological disorder known 

as Stem End Rind Breakdown of citrus (SERB) was determined. This disorder was found in thin-skinned fruit 

from humid, high rainfall areas and water stressed trees. Collapse of rind tissues not discolored around the 

button (thick layer of natural wax of cuticle) was the first symptom observed. Subsequently, the oil glands 

collapsed followed by discoloration of the collapsed area. Postharvest management practices that decrease 

fruit desiccation also reduce SERB incidence and severity. 

S09P09 

The effects of some post-harvest applications on fruit quality of ‘Valencia-Late’ oranges 

Dal B. 

Bati Akdeniz Agricultural Research Institute Antalya (Batem), Fruit Department, Turkey. banudal@yahoo.com 

During this research, the post harvest quality of ‘Valencia-Late’ sweet orange fruit was investigated. The 

study was carried out in the pomology laboratory and storage rooms of Batı Akdeniz Agricultural Research 

Institute in 2012. ‘Valencia-Late’ fruits were divided into six lots. The control group was left untreated during 

the trials. One lot of fruit was waxed immediately after harvest and other was dipped in ethanol (70%) 

solution. The other lots were dipped in propolis solutions (70% ethanol extracted propolis solution) of 3%, 

5%, 7%, respectively. Fruits were kept for 10 days at 20°C±1 and U-60 relative humidity and calculations and 

pomological analysis were conducted. During the trial, weight loss (%), fruit juice amount (g citric acid/100 

mL fruit juice), total soluble solid amount (%), titratable acid amount (%), total soluble solids/titratable acidity 

ratio, colour measurement and change in rind thickness (mm) were examined with three repetitions. 

S09P10 

Influence of light on carotenoid accumulation in ‘Star Ruby’ grapefruit 

Lado-Lindner J. 1 , Lado-Lindner J. 2 , Cronje P.J.R. 3 , Rodrigo M.J. 1 , and Zacarías L. 1 

1 Instituto de Agroquímica y Tecnología de Alimentos, Consejo Superior de Investigaciones Científicas (IATA-CSIC), Ciencia de los 

Alimentos, Spain; 2 Instituto Nacional de Investigación Agropecuaria (INIA), Postcosecha de cítricos, Uruguay; and 3 Citrus Research 

International (CRI), Horticultural Science, South Africa. jlado@iata.csic.es 

Accumulation of the red carotene pigment, lycopene, in citrus fruit is an unusual feature and restricted to 

grapefruit, pummelo and a few sweet orange mutants. Recent studies indicated that differential mechanisms 


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S09 

may be operating in the different lycopene-accumulating varieties, highlighting the importance to understand 

these processes. It is well characterized in citrus fruit that light positively affects color development and 

consequently carotenoid content and composition. However, it is paradoxical that by shading red grapefruit, 

degreening is accelerated and external color is enhanced (higher red coloration). To further understand the 

regulatory mechanisms of light on carotenoids biosynthesis in lycopene-accumulating grapefruit, carotenoid 

composition, and expression of carotenoid biosynthetic genes were analyzed in the peel of shaded and lightexposed 

‘Star Ruby’ grapefruit grown in South Africa and Spain. The stage of fruit development at the time of 

shading appears to be influential in color development. In the peel of shaded fruits, total carotenoids (x4) and 

particularly lycopene experienced a dramatic increased (x10). These changes were associated with a lower 

expression of early genes in the pathway as well as β-lycopene cyclase and β-carotene hydroxylase genes, 

envisaging their involvement in lycopene accumulation. In addition, the effect of light or shade exposure on 

other nutritional and health-related metabolites will be presented and discussed. 

S09P11 

Assessment of antioxidant compounds during storage period of ‘Valencia’ orange fruit 

Sharifani M.M. 1 , Mohamadi-Shamlou M. 1 , Daraei A. 2 , and Seifie E. 1 

1 Gorgan University of Agricultural Sciences and Natural Resources, Horticulture, Iran; and 2 Gorgan University of Agricultural Sciences 

and Natural Resources, Food Science and Technology, Iran. mmsharif2@gmail.com 

Citrus fruits have an important role to prevent from cardiovascular diseases. This effect is contributed to their 

antioxidants compounds which are able to absorb free radicals and active oxygen species. This compound 

could eliminate free radicals and decline the activity of effective enzymes in oxygen reduction pathway. In 

this study variation of antioxidant activity, total phenol and vitamin C content were determined during three 

months storage at temperature about 7° C and 85 % relative humidity (RH). Orange samples were treated with 

clove oil with 1% concentration, wax, wax-clove oil mixture and control. The amount of antioxidant activity was 

determined by DPPH method, and the total phenol compound and vitamin C were measured with folin-ciocalteu 

and 2,6 -diclrophenol indophenols titration methods respectively. The data used in a factorial statistical design 

in a frame of RCD using SAS software program. Results showed during storage period the total phenol had a 

decreasing trend while vitamin C contents had an increasing trend (42 days after storage) and then antioxidant 

activity was decreased. More discussion comes up on health status of fruits during storage. 

S09P12 

Postharvest ethylene treatment reduces quality loss of stored mature sweet orange ‘Navelate’ 

Lafuente M.T., Alférez F., and Romero P. 

Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Food Science. Postharvest Physiology and Biotechnology, Spain. 

mtlafuente@iata.csic.es 

Ethylene is usually associated with senescence but it may also play a role protecting fruits from stress conditions 

causing tissue damage. Its effect may be influenced by the concentration applied, the fruit physiological stage or 

the susceptibility of a specific cultivar to develop physiological disorders The industry only applies this hormone 

to citrus fruit for degreening purposes in spite of ethylene may reduce physiological disorders in mature fruits 

harvested after colour break. The effect of postharvest degreening on the quality of citrus fruit fruits has been 

documented. Nevertheless, there is no information on the effect of ethylene on the quality of fruits harvested 

after colour break and stored under commercial conditions required to extend its postharvest life. To address 

this question, we have examined the effect of treating mature ‘Navelate’ sweet orange (Citrus sinensis) for 4 

days with 2 µL/L ethylene at 90-95% RH on the quality of fruit stored at 2 or 12°C and 90-95% RH. Exposure to 

ethylene had little effect on increasing fruit colour but considerably reduced the incidence of calyx abscission, 

the incidence of non-chilling peel pitting at 12°C and of chilling injury after 40 days storage at 2°C. Ethylene had 

no deleterious effect on fruit firmness, weight loss, calyx senescence or acidity and reduced soluble solids by 

only 4%. Furthermore, ethylene did not enhance off-flavour perception and increased the content of bioactive 

flavonoids by about 18% in fruit stored for up to 40 days at 2 or 12°C. Therefore, treating the fruits with 2 µL/L 

ethylene may constitute a useful tool to extend postharvest life of mature citrus fruit since it reduces postharvest 

physiological disorders and has no negative effect on external or internal fruit quality 


S09P13 

Organoleptic quality and preservation of fruits tangerines cold storage in relation to application 

of waxes for postharvest 

Nascimento L.M., Machado M.A., Brito M.C.R., Moreira J., Brito P.C.N., and Sanches J.M. 

Instituto Agronômico, Brasil. lenice@centrodecitricultura.br 

This study aimed to develop new wax formulations with the requirements of the integrated citrus fruit 

production, in order to maintain the quality of citrus fruit with high commercial potential. These new wax 

formulations were suited to citrus varieties under study and the local conditions of production in the State of 

Sao Paulo and other Brazilian regions, allowing the production of fruits with good appearance and minimal 

change in flavor. The development of new formulations requires a detailed and comprehensive physiological 

study to allow the availability of reliable products that do not interfere with the physicochemical properties 

of the fruit during marketing. For that reason, it was necessary to evaluate some physical and chemical 

parameters that may somehow interfere with the flavor and appearance of the fruit. We evaluated two 

cultivars of mandarin: ‘Ponkan’ and ‘Decopon’. The main parameters analyzed to evaluate the effectiveness of 

new wax formulations were: texture, skin color, total acidity, soluble solids, °Brix, ratio, brightness, alcohols, 

weight loss and internal fruit quality by NMR. We evaluated the genetic code by the production region of the 

cultivars. The results showed that some formulations led to the change of taste, when subjected to sensory 

test by a panel of trained tasters. 

S09P14 

Effect of storage temperature on pitting development in satsuma ‘Okitsu’ 

Nuñez F.N. 1 , del Campo R.d.C. 2 , Pascale D.P. 3 , Díaz L.D. 2 , Solari J.S. 3 , Larrechart L.L. 1 , and Mara H.M. 2 

1 Empresa Citrícola (NORIDEL S.A.), Salto, Uruguay; 2 Instituto de Investigaciones Biológicas ‘Clemente Estable’ (IIBCE), Montevideo, 

Uruguay; and 3 Empresa Citrícola (MODISUR S.A), Salto, Uruguay. raqueldc60@gmail.com 

Rind disorders on satsuma mandarin originate serious postharvest losses in Uruguay. Causes of these disorders 

are not well understood and their incidence is erratic, with high variability from year to year and among 

orchards. Satsuma fruit suffered chilling injury during cold storage, and pitting are common postharvest 

symptoms. The objective of this study was to analyze fruit responses to different storage temperatures 

on pitting development and the incidence of different drench treatments on both fruit rot and pitting 

development. Satsuma ‘Okitsu’ fruit were harvested from two different farms, one with high pitting history 

(Q102) and the other with low pitting history (Q100). Fruit from each farm were drenched with five different 

treatments and compared to a non-treated control. After the drench treatment, fruit were degreened, waxed 

and stored at three different temperatures: 3°C, 6°C and room temperature, during 30 days. Fruit stored at 

room temperature did not show pitting. Fruit stored at 3°C showed the greatest pitting incidence. Farm Q102 

showed higher incidence of pitting than farm Q100. The different drench treatments affected rot incidence 

but not pitting level. Fruit stored at 3°C and 6°C had less incidence of fruit decay than that stored at room 

temperature. Rind samples from fruit with high pitting of Q102 and from fruit without pitting from both 

orchards Q100 and Q102 were analyzed for their nutrient composition. 

S09P15 

RNA-seq and phenylpropanoid metabolism of orange-Penicillium digitatum interaction 

Ballester A.R. 1 , Marcet-Houben M. 2 , Gabaldón T. 2 , Lafuente M.T. 1 , and González-Candelas L. 1 

1 Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Food Science Department, Valencia, Spain; and 2 Centre for Genomic 

Regulation (CRG-UPF), Comparative Genomics, Barcelona, Spain. ballesterar@iata.csic.es 

Penicillium digitatum is the causal agent of the Green Mold Rot of citrus fruit, being the major postharvest 

pathogen of these fruits in the Mediterranean-climate regions. The application of fungicides constitutes the 

most common method to control postharvest diseases. However, due to the development of resistance to 

fungicides among fungal pathogens and the growing public concern on their effects on human health and 

environment, there is a need to develop alternative methods to control postharvest diseases. In this study, 


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with the aim of better understanding the infection process on citrus, we used RNA-Seq transcriptomic analysis 

of infected oranges at 0, 24, 48 and 72 hours post-inoculation (hpi). Massive parallel pyrosequening with 454 

FLX Titanium technology was used for sequencing the libraries. To identify the putative origin of the reads, two 

reference genomes were used: (i) the Citrus sinensis Genome Assembly v1.0 (http://www.citrusgenomedb. 

org/), and (ii) the P. digitatum genome, elaborated in house (submitted). Quantitative reverse transcription 

PCR profiling of selected fruit and fungal genes revealed dynamic expression patterns during infection of 

oranges by P. digitatum. To further investigate the putative involvement of the phenylpropanoid pathway in 

the defense of citrus fruit, changes in the metabolic profile of the flavedo (outer colored part of the peel) 

and albedo (inner white part) infected with P. digitatum was studied by means of HPLC-PDA-FD. Metabolite 

accumulation levels along the time course suggest that flavanones, flavones, polymethoxylated flavones and 

scoparone are induced in citrus fruit in response to P. digitatum infection, although with different trends 

depending on the tissue. 

S09P16 

Disruption of the chitin synthase gene PdigChsVII in the citrus postharvest pathogen Penicillium 

digitatum 

Gandia M., Harries E., and Marcos J.F. 

instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Food Science, Spain. mgandia@iata.csic.es 

One of the main citrus postharvest pathogens is Penicillium digitatum, a citrus specific necrotrophic fungus 

that penetrates fruit through injured peel and is responsible for important losses. The development of new 

control methods as alternative to the current use of fungicides is urgently needed. Fungal cell wall (CW) is 

composed of chitin, glucans, mannans and glycoproteins, and is considered an excellent potential target for 

novel antifungals. In filamentous fungi, chitin is synthesized by a complex family of chitin synthase genes (Chs) 

grouped into seven classes. We have characterized P. digitatum Chs gene expression during different axenic 

growth conditions and fruit infection. Previous studies suggest a critical involvement in pathogenesis for Chs 

genes of Class V and Class VII. To determine functional relevance, we have obtained deletion mutants of 

PdigChsVII using Agrobacterium tumefaciens mediated transformation (ATMT). The resulting deletion strains 

(ΔPdigChsVII) showed reduced growth in axenic culture, higher sensitivity to CW-interfering compounds such 

as Calcofluor White (CFW) or SDS, and alterations of hyphal morphology. It also showed increase sensitivity 

to reactive oxygen species (ROS) such as H2O2. Infection assays of citrus fruits with ΔPdigChsVII showed 

virulence similar to the parental strain but defects in mycelium development and, importantly, also in conidia 

production. 

S09P17 

Proteins contributing to the pathogenicity of Penicillium digitatum towards citrus fruit 

Yamashita Y.K. 1 , Arimoto Y.A. 1 , Makino M.H. 2 , Annaka A.H. 1 , and Iida I.A. 1 

1 Riken (Riken), Arimoto Lab., Japan; and 3 Agriculture Optical Laboratory (AOL), Plant Disease, Japan. arimoto@riken.jp 

Penicillium digitatum, the causal agent of Citrus Green Mold, infects citrus fruit through injuries in the epicarp 

causing damage and decay. P. digitatum is widely distributed in citrus growing areas around the world and 

it is considered one of the most destructive pathogens of the citrus industry, resulting in losses of more 

than half of the harvested fruits. In environments in which pH is around 5.5, P. digitatum is saprophytic and 

does not invade living cells even if there is a wound. However, the fungus is pathogenic at pH lower than 3.5 

and infects not only citrus fruit, but all plant cells regardless of the species. In an effort to identify proteins 

contributing to pathogenicity towards citrus fruit, we performed a 2D-DIGE analysis of P. digitatum cultured 

in citrus epicarp exudate adjusted to pH 5.5 and pH 3.5. At pH 3.5, we identified SOD1, AHA1, CYPA, CYPB, 

and CFL as highly expressed proteins and TPIA as a low abundant protein. To investigate the contribution of 

each protein to citrus fruit infectivity, we generated a series of mutants in which the gene coding for each of 

these proteins was disrupted. The rate of infection of mature fruit was the same as the wild type for all the 

mutants but the rate of infection in immature fruit was dramatically reduced in the Δsod1 mutant. At the side 

of epicarp wounding, generation of O2 was 1.5 to 9 times greater in immature than in mature lemon fruit. 


SOD activity in the Δsod1 mutant was approximately 50% of the wild type. Furthermore, since cell invasion by 

P. digitatum is pH-dependent, we also investigated the pH-dependent transcription factor PacC. The ΔPacC 

mutant almost completely lost its pathogenicity towards mature fruit, suggesting that PacC also contributes 

to the P. digitatum pathogenicity. 

S09P18 

Identification and expression analysis of Penicillium digitatum genes involved in fungal virulence 

during citrus fruit infection 

de Ramón-Carbonell M. 1 , Ballester A.R. 2 , González-Candelas L. 2 , and Sánchez-Torres P. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología PVyB, Spain; and 2 Instituto de 

Agroquímica y Tecnología de Alimentos (IATA), Fisiología y Biotecnologíam Postcosecha, Spain. palomas@ivia.es 

Penicillium digitatum, the causal agent of Citrus Green Mold Rot, is the major pathogen of citrus fruit during 

postharvest. The control of this pathogen relies on the use of fungicides. However, due to the appearance of 

resistant strains and the harmful effects of synthetic fungicides on human health and the environment, there 

is a need to adopt new and safer control methods. Our knowledge of the mechanisms underlying pathogen’s 

virulence in postharvest pathogenic fungi, especially in Penicillium-fruit interactions, is still very poor. The aim 

of this study was to identify genes expressed in a virulent P. digitatum strain (Pd1) during the early stages of 

citrus fruit infection through suppression subtractive hybridization (SSH), using a low virulence P. digitatum 

isolate (CECT2954) as a driver. The subtracted cDNA library was sequenced using 454-FLX Titanium technology 

to perform a global transcriptomic analysis of putative fungal virulence genes. Gene expression analysis of 

selected P. digitatum genes putatively involved in fungal virulence was carried out by qRT-PCR. The expression of 

these genes was analyzed in both the high and the low virulent P. digitatum strains in three different situations: 

i) in orange disks after 24 h of P. digitatum interaction, ii) during growth of P. digitatum strains in PDB medium 

from 24 to 72 h and iii) in orange fruits during P. digitatum strains infection from 24 to 72 h. qRT-PCR profiling of 

selected fungal genes revealed different expression patterns during infection of orange fruits. 

S09P19 

Metabolism of flavonoids and mycotoxins in citrus fruits infected by Alternaria alternata 

Del Río J.A. 1 , Díaz L. 1 , Ortuño A. 1 , García-Lidón A. 2 , and Porras I. 2 

1 Faculty of Biology. University of Murcia. (UMU), Plant Biology, Murcia (Spain); and 2 Murcian Institute of Agriculture and Food 

Research and Development (IMIDA), Citriculture, Murcia (Spain). ignacio.porras@carm.es 

Fungi of the genus Alternaria are responsible for substantial pre-harvest losses in citrus. The susceptibility to 

A. alternata depends on the citrus species. In this communication, the metabolism of Alternaria mycotoxins 

and citrus flavonoids are analyzed in leaves and fruits of different citrus species and cultivars. HPLC-MS study 

revealed the presence of two A. alternata mycotoxins involved in the evolution of brown spot in leaves 

and fruits. These were identified as 3,7,9- trihydroxy-1-methyl-6H-dibenzo [b,d] piran-6-ona, known as 

alternariol (AOH), and 3,7-dihydroxy-9-methoxy-1-methyl-6H-dibenzo[b,d] piran-6-ona, known as alternariol 

monomethyl ether (AME). Biological assays involving the inoculation of leaves and fruits with the above 

mentioned toxins showed that both molecules caused necrosis in the inoculated citrus tissues, suggesting 

that the mycotoxins may be involved in the evolution of necrotic spot caused by A. alternata. The increased 

expression of the above mycotoxins was associated with the end of mycelial growth, high sporulation and 

an increase in hyphal melanisation. Citrus flavanones and flavones such as hesperidin, naringin, diosmin and 

sinensetin increased the biosynthesis of these micotoxins. On the other hand, a degradation of flavonoids 

was observed when leaves and fruits were infected with A. alternata. A decrease in the concentration of the 

flavanones hesperidin, naringin and their respective aglicons was observed in leaves and fruits of susceptible 

citrus. An increase of extracellular proteins with oxidant activity was detected in leaves and fruits inoculated 

with Alternaria. The study of substrate specificity, molecular weight and different inhibitors confirmed that 

Alternaria expressed an extracellular laccase, and that the citrus flavonoids are substrates of this enzyme. The 

involvement of mycotoxins, laccase enzyme and degradation of flavonoids in the pathogenesis of A. alternata 

in citrus is discussed. 


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S09P20 

Modulation of host responses by the biocontrol yeast Metschnikowia fructicola 

Hershkovitz V. 1 , Sela N. 2 , Rafael G. 1 , BenDayan C. 1 , Wisniewski M. 3 , and Droby S. 1 

1 The Volcani Center (ARO), Institute of Postharvest and Food Science, Israel; 2 The Volcani Center (ARO), Department of Plant 

Pathology and Weed Research, Israel; and 3 U.S. Department of Agriculture-Agricultural Research Service (USDA-ARS), Appalachian 

Fruit Research Station, U.S.A.. vhershko@agri.gov.il 

To gain a better understanding of the molecular changes taking place in citrus fruit tissue following the 

application of the yeast biocontrol agent, Metschnikowia fructicola, microarray analysis was performed on 

grapefruit surface wounds using an Affymetrix Citrus GeneChip. Using a cut off of p

were observed. Thus, other possible mechanisms of action can be involved. In this study, changes in 

enzymatic activity and gene expression level of chitinase, ß-1,3-glucanase, peroxidase, and phenylalanine 

ammonia lyase (PAL) in wounded and unwounded ‘Valencia late’ sweet orange treated with Na2CO3 and 

NaHCO3 (3% w/v), were investigated. Both salts increased ß-1,3-glucanase, peroxidase, and PAL activities in 

orange tissues, whereas chitinase activity decreased. Transcriptomic analyses confirmed PAL up-regulation, 

particularly at 12 h after treatment. Thus, although other pathways cannot be excluded, the defense 

response induced by Na2CO3 and NaHCO3 in citrus fruit seems to be correlated with the up-regulation of 

phenylpropanoid pathway, which has a role in the adaptation process to various stresses. This response 

could sum up to citrus natural reaction to wounding and pathogen attack, enhancing its protective effect. 

The results suggest that induced resistance should be considered as one of the possible mechanisms of 

salts in controlling postharvest citrus decay. 

S09P23 

In vitro and in vivo antifungal activity of eight medicinal plants against Citrus Sour Rot agent 

Geotrichum candidum 


Laboratoire des Biotechnologies et Valorisation des Ressources Naturelles (LBVRN), Biologie, Maroc. drissdesa@gmail.com 

The aim of this work was to find an alternative to the chemical fungicides currently used in the control of 

Geotrichum candidum, the cause of Citrus Sour Rot. Hexane, chloroform, ethyl acetate and methanol extracts 

of eight medicinal plants were evaluated for their in vitro and in vivo antifungal activity against G. candidum. 

Cistus villosus, Ceratonia siliqua and Halimium umbellatum methanol extracts proved to be the most effective 

inhibitors, totally inhibiting arthrospore germination of G. candidum at concentrations of 2.5 mg/mL and 

lower. The methanol extracts of H. umbellatum, C. villosus and C. siliqua exhibited strong antifungal activity 

with minimum inhibitory concentrations values ranged between 0.156 and 1.25 mg/mL, and minimum 

fungicidal concentrations values ranged between 2.5 and 5 mg/mL. Incidence of Sour Rot was lowered to 0, 

3.33 and 11.66% when mandarin fruit were treated with C. villosus, C. siliqua and H. umbellatum methanol 

extracts at 50 mg/mL, respectively, compared with 95% in the control. These findings suggest that C. villosus, 

H. umbellatum and C. siliqua plants may be useful and effective agents for control of Citrus Sour Rot. Such 

natural products therefore represent a sustainable alternative to the use of synthetic fungicides. 

S09P24 

In vitro and in vivo antifungal activity of several Moroccan medicinal plants against Penicillium 

italicum, the causal agent of Citrus Blue Mold 

Askarne L., Talibi I., Boubaker H., Boudyach E.H., Msanda F., Saadi B., Serghini M.A., and Ait Ben Aoumar A. 

Laboratoire de Biotechnologies et Valorisation des Ressources Naturelles (LBVRN), Biology, Morocco. as.latifa@gmail.com 

Penicillium italicum is the most important pathogen causing Blue Mold in stored citrus fruit. Current 

control treatments of the disease involve application of fungicides, which may have adverse effects on the 

environment and promotes the development of strains resistant to the active compound. To overcome these 

problems, and the increasing concern of consumers towards the use of fungicides, alternative methods for 

decay control are being investigated. The use of natural substances is a promising alternative that has been 

explored to manage postharvest decay of fruits. The aim of this study is to evaluate the antifungal activity of 

50 plant species, harvested in south of Morocco, against P. italicum infection. The in vitro antifungal activity 

of plant powders was determined using the agar plates method. Results showed that among the 50 plants 

tested, the powder of Anvillea radiata and Thymus leptobotrys at a concentration of 10% (w/v) completely 

inhibited mycelial growth of P. italicum. The effect of plant aqueous extracts on spore germination and germ 

tube elongation varied significantly among the different plants. Aquous extracts with high in vitro activity 

were also tested in vivo on sweet orange fruit. Incidence of Blue Mold was significantly lowered to 5 and 25% 

when fruits were treated with Halimium umbellatum and Inula viscosa aqueous extracts, compared with 98% 

in control fruits. 


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S09P25 

Effects of fluorescent Pseudomonas and Bacillus sp. on Blue Mold of citrus caused by Penicillium 

italicum 

Askarne L., Talibi I., Boubaker H., Boudyach E.H., Msanda F., Saadi B., Serghini M.A., and Ait Ben Aoumar A. 

Laboratoire de Biotechnologies et Valorisation des Ressources Naturelles (LBVRN), Biology, Morocco. as.latifa@gmail.com 

Blue Mold of citrus caused by Penicillium italicum is an important and devastating disease during storage of 

citrus fruits. Currently control treatments to manage this disease involve the application of synthetic fungicides, 

which have adverse effects on the environment and health. To overcome these problems and current concern 

of consumers towards the use of pesticides, alternative methods for decay control are needed. The use of 

antagonistic microorganisms is becoming popular throughout the world. A total of 466 bacteria isolated from 

the surface of citrus fruits, leaves and rhizospheric soil were in vitro screened for their antifungal activity 

against P. italicum. Results showed that among 110 active isolates, 69 were fluorescent Pseudomonas and 

41 belong to the Bacillus genus. Isolates which presented the widest inhibition zone (25 mm

fruits received the following treatments: T1 water (control), T2 0.16% IMZ PRM applied with RSS at the packing 

line, T3 wax 0.2% IMZ with RSS at the packing line, T4 dipping in 0.16% IMZ PRM for 30 seconds, T5 dipping in 

wax 0.2% IMZl for 30 seconds. Fruits were stored at 4ºC and 90% RH during 15 days and then at 20ºC and 90% 

HR during 7 days. Fruit damage were evaluated as % of control (incidence). The RAI levels were measured in 

fruit, flesh and essential oils. Results indicated that the best treatment was T4 with 100% disease control. The 

RAI in fruit were: 2 mg/kg of PRM and 3.8 mg/kg IMZ, and in essential oils: 104 mg/kg of PRMl and 182 mg/kg 

of IMZ. T2 treatment yielded 30 % of disease control and the RAI in fruit were: 1.2 mg/kg of PRM and 0.69 mg/ 

kg of IMZ and in essential oils: 89 mg/kg of PRM and 37 mg/kg of IMZ. No residue was detected in the flesh. The 

effectiveness of the application system was directly related to the RAI levels found in fruits and in essential oils. 

S09P28 

Resistant strains to postharvest fungicides in Algarve citrus companies. Packinghouse sampling 

and in vivo assays 

Salazar M. 1 , Mendes S. 2 , and Nunes C. 1 

1Instituto de Ciências Agrárias e Ambientais Mediterrânicas (ICAAM), Universidade do Algarve. FCT, Portugal; and 2Instituto Universitário D. Afonso III (INUAF), CICAE., Portugal. miguel.salazar@agro-on.pt 

Use of fungicides is the main way to control postharvest diseases of citrus fruits. Tiabendazole (TBZ) and imazalil 

(IZ) are the most used fungicides to control Penicillium digitatum and P. italicum. However, prolonged use of TBZ 

and IMZ leads to the selection of resistant strains. Therefore, to identify resistant strains and quantify the level of 

the resistant population in a packinghouse may be a useful management tool. Sampling methods are based on 

in vitro assays, but in vivo responses may differ, since disease development depends on many factors. The aim of 

this work was to quantify TBZ and IZ P. digitatum and P. italicum resistant strains in representative packinghouses 

in Algarve region, Portugal, and to evaluate its potential commercial impact by performing in vivo tests. Surveys 

were conducted during 7 seasons (2004-05 to 2010-11) using a gravimetric method with Petri dishes of PDA, 

PDA amended with 10 ppm of TBZ, and PDA amended with 1 ppm of IZ. Resistant strains were found in all 14 

packinghouses surveyed. Resistance to TBZ was around 24% and to IZ 11%, increasing over the years. Resistant 

strains were counted in samples from drenching treatments. In vivo experiments were conducted to evaluate 

the outcome obtained from in vitro assays. In spite of variability observed, the incidence of resistant strains in 

commercialized fruits is of paramount importance and should be the subject of further work. 

S09P29 

Influence of paraben concentration on the development of Green and Blue Molds on ‘Valencia’ 

orange fruit 

Moscoso-Ramírez P.A. 1 , Montesinos-Herrero C. 1 , and Palou L. 2 

1Colegio de Postgraduados (COLPOS), Campus Tabasco, H. Cárdenas, Tabasco, México; and 2Institut Valencià d’Investigacions Agràries 

(IVIA), Centre de Tecnologia Postcollita (CTP), Spain. palou_llu@gva.es 

Three paraben sodium salts (p-hydroxy-benzoate) were evaluated as postharvest treatments to control Citrus 

Green and Blue Molds, caused by Penicillium digitatum and P. italicum, respectively. The curative activity of 

sodium methyl (SMP, at 0.1, 1, 10, 40, 70, 100, 150, 200 and 250 mM), ethyl (SEP, at 0.1, 1, 10, 20, 30, 40, 

70, and 100 mM) and propyl (SPP, at 0.1, 1, 4, 7, 10, and 100 mM) parabens was evaluated on ‘Valencia’ 

sweet orange fruit by inoculating P. digitatum and P. italicum in rind wounds and, about 24 h later, placing a 

drop of the solutions in the same rind wound. Disease development was assessed on fruit incubated at 20ºC 

for 6 days. All three paraben salts reduced mold development. Concentrations of 150, 200 and 250 mM of 

SMP were the most effective and completely controlled both diseases. Concentrations of 20, 30, 40, 70 and 

100mM of SEP reduced the incidence of Green and Blue Mold by 100, 94, 100, 100 and 73% and 87, 62, 93, 

100 and 80%, respectively. Concentrations of 7, 10 and 100 mM of SPP reduced the incidence of Green and 

Blue Mold by 94, 89 and 94% and 70, 88 and 100%, respectively. Most of these concentrations of SMP, SEP 

and SPP also significantly reduced the severity of both diseases. SMP at 200 mM, SEP at 80 mM and SPP at 

100 mM were, among the range of concentrations tested, selected as the best to be used in further research. 


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S09P30 

Selection and in vitro evaluation of yeasts for control of Geotrichum candidum 

Cunha T. 1 , Tosin E.S. 2 , and Kupper K.C. 3 

1 Universidade Estadual Paulista ‘Júlio Mesquita Filho’ - Campus de Jaboticabal (UNESP), Microbiologia Agropecuária, Brazil; 

2 Universidade Federal de São Carlos - Campus Araras (UFSCar), Ciências Biológicas, Brazil; and 3 Centro APTA Citros Sylvio Moreira 

(IAC), Fitopatologia e Controle Biológico, Brazil. taticunha1989@hotmail.com 

This paper aimed to test different yeast isolates obtained from soils, leaves, fruits and flowers of citrus from 

different places in the State of São Paulo/Brazil for the antagonism to Geotrichum candidum, the causal agent 

of Sour Rot of citrus. The decimal dilution technique, plating in YPD, YM and WLN medium, was used for the 

isolation of potential antagonists. The colonies obtained were incubated at 25° C for 7 days in BOD chamber and 

the isolated showing a distinctive morphology were purified in YEPD medium. These isolates were evaluated 

for the antagonism by means of dual cultures in Petri dishes. The experiment was arranged in a completely 

randomized design, with six replicates and the evaluation was performed by measuring the average diameter 

of colony growth. The effect of yeast strains on the spore germination of G. candidum was assessed using the 

technique of water-agar on glass slides, evaluating the 15 isolates with higher inhibitory effect in vitro. A total of 

87 yeast isolates were obtained, and the best results were obtained with the yeast isolates ACBL-77, ACBL-23, 

and ACBL-52, with a inhibitory effect ranging from 28% to 35%. The germination test showed that, except ACBL- 

21, all isolates significantly inhibited the germination of G. candidum spores. The isolates ACBL-68 and ACBL-23 

showed the highest inhibitory rates, with values of 87.7% and 83.4%, respectively. 

S09P31 

In vitro and in vivo evaluation of yeast isolates for biocontrol of Penicillium digitatum, causal 

agent of Green Mold 

Kupper K.C. 1 , Cunha T. 2 , and Tosin E.S. 3 

1 Centro APTA Citros Sylvio Moreira (IAC), Fitopatologia e Controle Biológico, Brazil; 2 Universidade Estadual Paulista Júlio Mesquita 

Filho - Campus de Jaboticabal (UNESP), Microbiologia Agropecuária, Brazil; and 3 Universidade Federal de São Carlos - Campus de 

Araras (UFSCar), Ciências Biolólicas, Brasil. katia@centrodecitricultura.br 

This work aimed to test different yeast isolates obtained from soils, leaves, fruits and flowers of citrus from 

different places in the State of São Paulo/Brazil for in vitro and in vivo antagonism to Penicillium digitatum, the 

causal agent of Green Mold. The in vitro evaluation was performed by means of dual cultures in Petri dishes. 

The experiment was arranged in a completely randomized design, with six replicates and the evaluation 

was performed by measuring the average diameter of colony growth. ‘Valencia’ sweet orange fruit (Citrus 

sinensis) were washed and surface disinfected with a 0.7% sodium hypochlorite solution Fruit were injured in 

two equidistant points with a 3 mm depth needle and inoculated with a conidial suspension of P. digitatum 

(10 5 spores/mL) 24 hours before and after the treatments. Treatments were applied by dipping the fruits into 

the antagonist suspensions (10 7 cfu/mL) for 2 minutes, or a fungicide solution of imazalil (0.2%). Inoculated 

non-treated fruit were considered as control. All fruits were maintained at 20ºC and 99% RU for 7 days. A 

completely randomized design with three replicates of 20 fruits was used. Control efficacy was evaluated 

based on the percentage of diseased fruits. The best results in vitro were obtained with the isolates ACBL-07, 

ACBL-14, ACBL-58 and ACBL-67, but they were ineffective in the assays in vivo. 

S09P32 

Optimal concentration of inoculum, types of injuries and control of Penicillium digitatum in 

orange fruits 

González-Fierro P. 1 , Nieto-Ángel D. 1 , Téliz-Ortiz D. 1 , Lara-Viveros F.M. 1 , and Orozco-Santos M. 2 

1 Colegio de Postgraduados (CP), Instituto de Fitosanidad, México; and 2 Instituto Nacional de Investigaciones Forestales, Agrícolas y 

Pecuarias (INIFAP), Campo Experimental Tecomán, México. orozco.mario@inifap.gob.mx 

Green Mold, caused by Penicillium digitatum, is the most important postharvest disease of citrus in Mexico. 

The objectives of this study were: 1) to evaluate the effect of nine different spore concentrations of the fungus 

in orange fruits, 2) to determine the effect of three types of injuries to allow the disease after inoculation, and 


3) to evaluate different treatments for disease control. Disease was observed in 100% of the inoculated fruits 

when the inoculum concentration was equal or higher than 6x10 5 spores/mL. Symptoms did not appear with 

concentrations of 1x10 4 and 3x10 4 spores/mL. When injuries were superficial (bruises and deformation) and 

did not penetrate into the albedo, the infection did not occur. Wounds caused by punctures and cuts induced 

symptoms after the inoculation. All treatments with Trichoderma viride and T. harzianum, as well as the 

extract of Melaleuca aternifolia, failed to reduce disease incidence and severity in fruits. The best treatments 

to control Green Mold were the fungicides pyrimethanil and thiabendazole. 

S09P33 

In vitro comparison of the effectiveness of disinfectants and a fungicide on the viability of spores 

of Geotrichum citri-aurantii. 

Diaz L.D. 1 , del Campo R.d.C. 2 , Peyrou M.P. 2 , and Mara H.M. 2 

1Dirección General de Sevicios Agrícolas (MGAP), Montevideo, Uruguay; and 2Instituto de Investigaciones Biológicas ‘Clemente 

Estable’ (IIBCE), Montevideo, Uruguay. raqueldc60@gmail.com 

Sour Rot (Geotrichum citri-aurantii) is an important postharvest disease of citrus in Uruguay. The disease has 

been managed so far by using sodium orthophenylphenate (SOPP) and 9-Aza-1,17-diguanidinoetadecane 

(guazatine). Both fungicides leave residue levels in fruit that are generally not acceptable for export. Therefore, 

the development of alternative control treatments, such as disinfection, is required. The objective of this 

work was to compare the effect of various disinfectants and one fungicide on the viability of Geotrichum 

spores in vitro. The products evaluated were: 200 ppm sodium hypochlorite, 100 ppm stabilized chlorine 

dioxide (Tecsaclor®), pH 6 and 6.5; 5000 ppm chloramine-T (Bac-T®); 1600 ppm didecyl dimethyl ammonium 

chloride/ alkyl amido propyl chloride dimethyl benzyl ammonium chloride (Tefor®); 120 ppm dimethil didecyl 

ammonium chloride (Sporekill®). The efficacy of 20000 ppm SOPP was also evaluated. For all treatments, a 

suspension containing 106 spores/mL was prepared and exposed directly to each product solution for 1, 2 

or 4 min. The results obtained were compared with those of untreated control fruit. The highest efficiency 

was obtained for ammonium and chlorine dioxide (pH 6) compounds, which reduced 100% spore viability 

for the three exposure times evaluated. Sodium hypochlorite during 2 and 4 min killed 97% and 100% of the 

spores, respectively. Tecsaclor (pH 6.5) reduced 99.8% and 100% of the spores after 2 and 4 min of exposure, 

respectively. SOPP did not produce a satisfactory effect. 

S09P34 

Alternative treatments for postharvest decay control on ‘Ponkan’ tangerines 

Montero C.R.S. 1 , dos Santos L.C. 2 , Andreazza C.S. 2 , Schwarz L.L. 2 , and Bender R.J. 2 

1 (Fepagro), Research Station Serra do Nordeste, Caxias do Sul; and 2 (UFRGS), Horticultural Sciences, Agronomy, Brazil. rjbe@ufrgs.br 

Penicillium spp. are the most frequent pathogens associated with postharvest decay in citrus fruit. Pre- and 

postharvest chemical sprays are the most widespread methods to reduce incidence, though, in the scientific 

literature there is plenty of evidence on promising alternative postharvest treatments. Therefore, in the 

present work the objective was to evaluate the effects of alternative treatments on the control of Green 

and Blue Mold and on the postharvest quality of ‘Ponkan’ tangerines. During two seasons, fruit harvested in 

commercial orchards were treated with different combinations of sodium bicarbonate, potassium sorbate, 

and heat treatments, in single or combined applications. Two control treatments, chloride dioxide and imazalil 

were also included. The tangerines were evaluated after 15 or 30 days of cold storage at 5°C plus 5 more 

days at room temperature for internal quality and decay incidence. Quality traits were not affected by any 

of the treatments. Sodium bicarbonate at a concentration of 2% (w/v) and potassium sorbate at 0,5% (w/v) 

significantly reduced decay on ‘Ponkan’ fruit after 30 days of storage. However, peel brightness was negatively 

affected by an immersion treatment of 30 sec at 58°C with both salts at concentrations higher than 3% and 

1%, respectively. Further research on salt concentration and temperature combinations should be conducted 

to conclude about the feasibility of alternative postharvest treatments for citrus fruit. 


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S09P35 

Curative and protective control of Penicillium digitatum following imazalil application in aqueous 

dip and wax coating 

Njombolwana N.S., Erasmus A., and Fourie P.H. 

Stellenbosch University, Citrus Research International (US, CRI), Plant Pathology, South Africa. shellie@sun.ac.za 

Imazalil (IMZ) is widely used in citrus packhouses to manage Green Mould, caused by Penicillium digitatum. 

The aim of this study was to investigate curative and protective green mould control by IMZ when applied 

in a postharvest wax coating, and double IMZ application in aqueous dip followed by coating. Trials were 

conducted on clementine, satsuma, ‘Navel’ and ‘Valencia’ sweet orange fruit and treatments were dip only 

(IMZ sulphate at 500 µg/mL for 45 s and 90 s), wax coating only (imazalil at 3,000 µg/mL at 1.8 L wax/ton), 

and a double application comprising of dip (45 s in IMZ sulphate at 500 µg/mL) followed by 2,000 µg/mL 

IMZ in wax coating at 0.6, 1.2 and 1.8 L wax/ton. Double application generally improved IMZ residue loading, 

more so with increasing coating load, while the wax coating only resulted in the highest residue level. Poor 

curative and protective control of the resistant isolate was observed (

acid, sodium carbonate and sodium metabisulfite at 0.25% (w/v). Medium-pH in the range of 4.0 to 12.0 did 

not influence mycelial growth of the pathogen. The ten best salt compounds were tested for their ability to 

reduce arthrospore germination. The effects of salts varied significantly (P

Session 10 

WATERING AND NUTRITION 

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S10O01 

Open hydroponics of citrus compared to conventional drip irrigation best practice: first three 

years of trialling and Australian experience 

Falivene S1 , Navarro Acosta J.M. 2 , and Connolly K1 . 

1NSW Department of Primary Industries (NSW DPI), Intensive Industries, Australia; and 2Dpto. Citricultura Instituto Murciano de 

Investigación y Desarrollo Agrario y Alimentario (IMIDA), Spain. steven.falivene@dpi.nsw.gov.au 

Hydroponics is a system of growing plants in an inert media (e.g. rockwool), supplying the plants’ nutrition 

using mineral salts dissolved in the irrigation water and irrigating frequently throughout the day. “Open 

Hydroponics” (OH) is a system where trees are grown in soil, but nutrient needs are managed similarly to 

hydroponics and trees are irrigated throughout the day. OH is a relatively recent production innovation, and 

is being adopted around the world, and there are anecdotal reports of superior yields attributed to OH. But, 

OH programs do not necessarily consider the soil as a critical part of the production program. This has raised 

concerns regarding soil acidification, waterlogging and nitrate leaching. Few scientific data are available on 

OH, and there is an industry-wide knowledge gap. A replicated extension trial was conducted to compare 

citrus OH to conventional practice in young citrus. In the first three years, data indicates no differences in yield, 

tree growth, soil and/or leaf nutrient dry matter content. Soil solution data is highly variable but indicates that 

adequate levels of nitrogen are present in the soil for both programs. Anecdotal evidence suggests acidifying 

irrigation water has no benefit and water use in pulse irrigation is higher than best practice conventional. The 

uptake of OH in Australia has been mixed, some growers have benefited and others have found no benefit 

and reverted to conventional practice. 

S10O02 

Deficit irrigation strategies: preliminary assessment on a Sicilian young orange orchard 

Stagno F. 1 , Parisi R. 2 , Cirelli G. 2 , Consoli S. 2 , Roccuzzo G. 1 , Barbagallo S. 2 , and Intrigliolo F. 1 

1 Citrus and Mediterranean Crops research centre - CRA (CRA-ACM), Italy; and 2 Università di Catania (DiGeSA), Dipartimento di 

Gestione dei Sistemi Agroalimentari e Ambientali, Italy. giancarlo.roccuzzo@entecra.it 

The economical sustainability of citrus orchards has to cope with the availability of water resources. One way to 

optimise water resources is to employ deficit irrigation (DI) strategies. DI effects on some physiological characters 

of young orange orchards were analysed. The orchard includes 300, 4-years old, plants located at the CRA-ACM 

experimental farm in Lentini, Sicily (37° 20’N; 14° 53’E). Four irrigation strategies were replicated 4 times: (i) Subsurface 

drip irrigation, supplying 75% IR (irrigation requirement), (ii) Partial root-zone drying, supplying 50% IR, 

(iii) Regulated deficit irrigation, supplying 50-100% IR, depending on crop phenological phases and (iv) Surface 

drip irrigation, supplying 100% IR. The IR was calculated using the Penman-Monteith approach, by assuming a 

crop coefficient of 0.45, and correction coefficients accounting for the localized irrigation. On selected plants, 

measurements of LAI, PAR, xylematic potential, canopy temperature, gas exchanges, trunk diameter and shoot 

number were carried out. Soil water content (SWC) was monitored by using Time (and Frequency) Domain 

Reflectometry. Preliminary results, obtained during the 2011 season, showed that: (i) xylematic potential and 

stomatal conductance were slightly variable between the investigated treatments with values quite below the 

stress condition, (ii) LAI and PAR were slightly variable between each plant and treatments, (iii) SWC was below 

the field capacity, (iv) trunk diameters were quite similar among the analysed plants. 

S10O03 

Citrus water use in South Africa 

Vahrmeijer J.T. 1 , Annandale J.G. 2 , Gush M.B. 3 , and Taylor N.J. 4 

1Citrus Research International (CRI), Fruit Production and Quality, South Africa; 2University of Pretoria (UP), Plant Production and Soil 

Science, South Africa; 3Counsel for Scientific and Industrial Research (CSIR), Natural Resources and the Environment, South Africa; and 

4University of Pretoria (UP), Plant Production and Soil Science, South Africa. jtv@up.ac.za 

Agriculture, as the largest user of fresh water worldwide, is under close scrutiny to justify its use of water, 

due to the increase in competition from a number of end-users. Apart from on-farm measures to increase 


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S10 

water use efficiency, government intervenes through policy instruments to influence water use behaviour. 

Citrus growers need to take heed of these changes in policy as the majority of citrus orchards are irrigated 

and more detailed information on seasonal water requirements and irrigation scheduling is needed to justify 

the quantity of water needed for the production of citrus. However, measurements of citrus orchard water 

use are not possible for all environmental and management combinations, primarily due to the expense 

and time it takes to make the measurements. Models, which are formidable tools to predict water use and 

crop performance, are therefore vital to provide accurate estimates of citrus water use across different 

climatic regions. In order to model citrus water use, a thorough understanding of the factors governing citrus 

water use is required. Results from measurements performed in a number of citrus orchards across climatic 

zones in South Africa indicated that citrus water use, under conditions of unlimited soil water supply, is not 

solely governed by atmospheric demand, but also by internal resistances to water movement within the 

plant, which limits the amount of water that a citrus tree can transpire on hot dry days. Increasing irrigation 

volumes during days with high evaporative demands will therefore not necessarily reduce tree stress but 

may exacerbate the problem, by increasing root resistance, as a result of poor aeration. We will report on the 

institutional arrangements regarding water use and results from current and previous research on the water 

use in citrus in South Africa. 

S10O04 

Evapotranspiration over an irrigated orange orchard using micrometeorological techniques and 

sap flow measurements 

Consoli S. 1 , Continella A. 2 , Motisi A. 3 , Papa R. 1 , and Pasotti L. 4 

1 University of Catania (DIGESA), Department of Agri-food and Environmental Systems Management, Italy; 2 University of Catania 

(DISPA), Department of Agricultural and Food Science, Italy; 3 University of Palermo (DEMETRA), Italy; and 4 Regione Siciliana (SIAS), 

Servizio Informativo Agrometeorologico Siciliano, Italy. acontine@unict.it 

During recent years, a substantial progress in understanding the evolution of evapotranspiration processes 

in cropping systems has produced detailed models and innovative measurement techniques for describing 

the mass (water, CO 2 ) and energy (solar radiation) exchanges in the soil-plant-atmosphere continuum. Within 

this context, the aim of the study was to investigate, develop and validate integrated approaches to better 

understand and quantify mass and energy exchanges processes in an orange orchard in the Mediterranean 

environment. Different micrometeorological techniques, (i.e. eddy covariance, surface renewal analysis of 

the sensible heat fluxes, surface energy balance), were used to estimate the evapotranspiration fluxes of 

the irrigated orange grove in eastern Sicily (Italy). Transpiration was determined by the sap flow method. 

The results are referred to a 2-year period and showed satisfactory comparisons between the investigated 

methods. The findings of this study will allow for the definition of suitable techniques and methodology for 

the rational management of water resources in the tree crop environment under water scarcity conditions. 

S10O05 

Partial root-zone drying effects under different rootstocks and irrigation systems in Valencia, Spain 

Ortega J. 1 , Forner-Giner M.A. 2 , Quiñones A. 2 , Legaz F. 2 , and Intrigliolo D.S. 1 

1 Insituto Valenciano Investigaciones Agrarias (IVIA), Sustainable Agriculture, Spain; and 2 Insituto Valenciano Investigaciones Agrarias 

(IVIA), Citriculture, Spain. intrigliolo_die@ivia.gva.es 

Citrus trees culture in Spain is mainly located in areas of water scarcity. It is then important to improve 

irrigation efficiency. With this aim, a research has been conducted in order to explore if partial root-zone 

drying (PRD), an irrigation technique aimed at alternating water applications along the two sides of a tree, 

could be used to increase water use efficiency (WUE). The research was conducted in Valencia in field and 

pot conditions under superficial and subterraneous drip irrigation systems and under different rootstocks 

(Carrizo citrange and the Forner-Alcaide dwarfing hybrids). In a first set of pot experiments, plantlets were 

submitted to either full water application, or deficit irrigation either, under PRD or conventional watering. 

Deficit irrigation allowed increasing WUE (total dry mass produced/water transpired), but PRD did not lead 

to any significant gain in WUE when compared to conventional DI regardless the rootstock employed. In field 

conditions, under a given watering regime, sub-surface drip irrigation allowed improving tree water status, 


gas exchange, foliar SPAD index and yield when compared with superficial irrigation. On the other hand, deficit 

irrigation increased P, K and Na foliar concentrations but reduced yield and affected fruit quality (increasing 

fruit acidity). Overall the results indicate that deficit irrigation and the sub-surface irrigation system can be 

both used as measures for increasing plant WUE. However, PRD, contrarily to previous evidence obtained 

in more arid environmental conditions, did not allow any gain in plant performance when compared with a 

similar watering regime. Our results question the applicability of the more expensive PRD irrigation system in 

the commercial citrus orchards of the Valencia region. 

S10O06 

A critical evaluation of citrus leaf mineral status guidelines for optimal yield in Israel 

Raveh E. 

Agricultural Research Organization (ARO), Fruit trees, Israel. eran@agri.gov.il 

Maintaining orchards at optimal leaf mineral concentration is one of the key issues for maximal yield. Experiments 

for verifying and updating guidelines are very rare since they require several years of field experiments in mature 

bearing trees which are expensive. The evaluations of such guidelines at the grower level are more complicated 

processes and therefore usually not done. -In the present paper we first evaluate the Israeli guidelines for citrus 

by comparing them to the Israeli orchards leaf mineral status using a 10 year leaf mineral database (results from 

20244 leaf analysis that were sampled from commercial orchards all over Israel). Then we tried to create an 

updated guideline using a second database that summarized yield and leaf mineral concentration collected from 

122 orchards all over Israel over 7 years (the Israeli National Wastewater Effluent Irrigation Surveys database). 

There was a disagreement between the local recommendations and the orchards leaf mineral status (e.g local 

recommendation were higher than orchard median values), which demonstrates the needs for guidelines 

updating. Based on the Israeli National Wastewater Effluent Irrigation Surveys database a new guideline was 

set. It was found that the optimal leaf mineral concentration for grapefruit is 1.7-2.1% DW of N, 0.08-0.010% DW 

of P, 0.37-0.48% DW of K, and 0.33-0.45% DW of Mg. For orange trees the optimal leaf mineral concentration is 

1.9-2.3% DW of N, 0.11-0.14% DW of P, 0.80-1.00% DW of K, and 0.19-0.26% DW of Mg. For easy peelers trees 

the optimal leaf mineral concentration is 2.0-2.4% DW of N, 0.09-0.12% DW of P, 0.55-0.69% DW of K, and 0.19- 

0.26% DW of Mg. Maintaining the leaf within this rages can allow maximal yield of 110-120 t/ha for grapefruits, 

65-70 t/ha for oranges, and 60-70 t/ha for easy peelers. 

S10O07 

What limits nitrogen fertilization responses of fertigated citrus orchards under tropical 

conditions? 

Mattos Jr. D. 1 , Quaggio J.A. 2 , Boaretto R.M. 1 , Souza T.R. 2 , and Zambrosi F.C.B. 2 

1 Instituto Agronômico (IAC), Centro de Citricultura Sylvio Moreira, Brazil; and 2 Instituto Agronômico (IAC), Centro de Solos e Recursos 

Ambientais, Brazil. ddm@centrodecitricultura.br 

Fertigation of citrus orchards was recently adopted by growers in Brazil. The inherent low fertility and 

acid soils under the tropics implies that efficient nutrient management practices need to be conducted to 

ensure high fruit quality and yield. A field experiment with Valencia sweet oranges on Swingle citrumelo was 

established in 2003 when trees were 3-4-year old and conducted during a six-year period. Trees received 

60, 120, 180 and 240 kg/ha per year of N, as ammonium nitrate (AN) or calciun nitrate (CaN), via fertigation 

using two dripper lines per row. Fruit yield for pooled data reached 70 t/ha with 180 kg/ha of N as AN, what 

agrees with reported fertilization curves, in which this maximum is attained with N rates of approximately 

200 kg/ha. On the other hand, fruit yield increased linearly up to 85 t/ha with the highest N rate as CaN. Soil 

analysis demonstrated that acidification was greater after AN applications. In this case, soil pH was below 

4.6 in the surface and 3.8 at deeper soil layers despite frequent liming applications to the soil. This resulted 

from increased ammonium uptake by roots, what correlated with nutrient concentrations in soil solution 

extracts. Leaf Ca was

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S10O08 

Uptake of 44Ca and 15N by young citrus trees 

Quiñones A., Martínez-Alcántara B., Alcayde E., and Legaz F. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Citriculture and Vegetal Production, Spain. legaz_fra@gva.es 

Calcium is a macroelement involved in numerous physiological processes in plants, such as the division 

and growth of cells. Calcium is part of the structure of cell walls and membranes and together with the 

magnesium participates in the activation of metabolic enzymes of proteins and carbohydrates. There are 

numerous studies on Ca conducted in the plant-soil system, however no information is available on their 

absorption and distribution among different organs. In this sense, the use of 44 Ca and 15 N as tracers is a useful 

tool since allows to know exhaustively the fate of the element applied in the plant-growing medium system. 

Ca absorption by plant roots depends on several factors, among which are the availability of this nutrient in 

the culture medium. Therefore, the main objective of this study is to evaluate the response of 7 different 44 Ca 

and 15 N concentrations on their uptake and their distribution among different organs in young plants of citrus 

grown in sand substrate in a growth chamber. At the end of the labelling period, plants were fractionated 

into young developing organs, old leaves, stem, coarse and fibrous roots. Increasing Ca concentration did not 

affect significantly the biomass of the different organs. However, significant differences were obtained in 44 Ca 

and 15 N uptake. Ca uptake efficiency decreased from 28% to 15% when increasing Ca supplied (0.5 mM to 

32 mM), while N uptake efficiency decreased from 49% to 17% (2.5 mM to 70 mM). Whereas Ca was mainly 

partitioned to coarse roots, N accumulated in new flush leaves. 

S10O09 

A new approach to front citrus iron chlorosis: organo-mineral fertilizers from glass-matrix and 

organic biomasses 

Torrisi B. 1 , Trinchera A. 2 , Allegra M. 3 , Epifani R. 2 , Marcucci A. 2 , Roccuzzo G. 1 , Intrigliolo F. 1 , and Rea E. 2 

1 Centro di ricerca per l’Agrumicoltura e le Colture Mediterranee (CRA-ACM), ITALY; 2 Centro di ricerca per lo studio delle Relazioni tra 

Pianta e Suolo (CRA-RPS), ITALY; and 3 Centro di ricerca per l’Agrumicoltura e le Colture Mediterranee (CRA-ACM), ITALY. 

francesco.intrigliolo@fastwebnet.it 

The aim of the present paper was to deepen the agronomical responses of glass-matrix based fertilizers 

(GMF), a typology of fertilizer able to release nutrients on the basis of plant-demand, whose nutrient release 

increases thanks to the mixing with organic biomasses, such as digested vine vinasse (DVV) and meat-meal 

(MM). Laboratory tests and short-term pots trials provided concurring results about the attitude of the mixture 

GMF DVV to increase nutrient availability and plant development. In the following stage these mixtures were 

tested for their ability to contrast citrus iron chlorosis in calcareous soils, the most complex phenomenon in 

citrus orchard and one of major abiotic stresses affecting fruit tree crops in the Mediterranean area. Three 

years studies were realized: i) in pots, on ‘Tarocco Scirè’ orange trees [Citrus sinensis] grafted on two different 

rootstocks (Carrizo citrange and Swingle citrumelo) and ii) in field, on ‘Tarocco Scirè’ on sour orange rootstock 

[C. aurantium], by comparing GMF and its mixtures with DVV and MM application to a synthetic Fe chelate 

one. The GMF DVV mixture was able to supply adequately micronutrients, particularly iron, reducing the 

chlorosis symptoms, increasing the leaf SPAD index, Fe concentration and decreasing Fe index. 

S10O10 

Nitrogen and calcium equilibrium on citrus nutrition 

Quaggio J.A. 1 , Souza T.R. 1 , Boaretto R.M. 2 , Zambrosi F.C.B. 1 , and Mattos Jr. D. 2 

1 Instituto Agronômico (IAC), Center of Soil, Brazil; and 2 Instituto Agronômico (IAC), Center of Citriculture, Brazil. 

quaggio@iac.sp.gov.br 

Nitrogen (N) and calcium (Ca) are major nutrients in citrus trees and responsible for the ionic equilibrium of 

plant cells. Additionally, Ca absorption is directly affected by the form of N supply; e.g. ammonium or nitrate. 

Therefore, high yield and fruit quality of citrus depend on balanced application of those, especially under intensive 

nutritional program as fertigation. The objective of this study was to evaluate the mineral N and Ca2 absorption 


y citrus and consequent effects on nutrient concentrations in young mature leaves, stem sap extracts and wet 

bulb soil solution, and fruit yield. Data from two long-term field trials were evaluated in fertigated orchards with 

10 to 12 –year old Valencia on Swingle citrumelo rootstock, with N rates varying from 0 to 240 kg ha -1 yr -1 applied 

either as ammonium or calcium nitrates. The trials were monthly monitored by nutrient analyses. The results 

along two seasons showed: (i) an interdependence of N and Ca absorption, (ii) decreased N-NO 3 -/N-NH 4 ratio 

in the soil solution and in the sap extracts with increased ammonium nitrate rates, which negatively affected 

Ca absorption and its concentration in the sap extract and leaves, (iii) maximum fruit yield was attainted with 

N-NO 3 -/N-NH 4 - ratios of 25 and 7, respectively, in the wet bulb solution and the sap extract, and (iv) unbalance 

absorption of cations and anions caused by excessive N-NH 4 absorption and, consequently, decreased soil pH 

solution, what compromises the fertigation sustainability of citrus groves in tropical soils. 

S10P01 

Physiological and nutritional responses of Navel orange trees to different irrigation and 

fertigation practices 

Navarro J.M. 1 , and Falivene S. 2 

1 Instituto Murciano de Investigación y Desarrollo Agrario y Alimentario (IMIDA), Citricultura, Spain; and 2 NSW Department of Primary 

Industries (NSW DPI), Australia. josefam.navarro2@carm.es 

A trial was established on drip irrigated Atwood Navel orange trees growing in Australia to compare daily 

irrigation with conventional practices. Trees were subjected to five treatments of combined irrigation and 

fertigation treatments: conventional irrigation application of conventional nutrients; daily pulse irrigation 

application of conventional nutrients; conventional irrigation proportional injected nutrition; daily pulse 

irrigation proportional injected nutrition and continuous irrigation proportional injected nutrition. Since 

irrigation methods could modify the tree water status and fertigation could alter trees nutrition, we studied 

the physiological response during the summer-autumn period and the nutritional state after three years of 

application of the treatments. Trees were well-irrigated in all treatments, even at the most critical moments, 

and no clear differences in gaseous exchange parameters were found with different irrigation treatments. 

Conventionally irrigated trees had similar water potential values to daily irrigated trees and these values were 

always far away from the threshold for well-irrigated trees. When nutrients were applied in a conventional 

way, irrigation practices did not modify foliar N, P, and K levels; with proportional injected nutrition, pulse 

irrigation increased K and P foliar levels. As conventionally irrigated trees consumed lower amounts of water 

and had a similar yield to daily irrigated trees, they presented the highest water use efficiency. 

S10P02 

Influence of precipitation in the fruit growing season on sugar accumulation in Satsuma 

mandarin fruit juice 

Takishita F. 1 , Uchida M. 2 , Hiraoka K. 1 , and Nesumi H. 2 

1 National Institute of Fruit Tree Science (NIFTS), Kuchinotsu, Japan; and 2 National Agricultural Research Center for Western Region 

(WeNARC), Citrus innovative production team, Japan. takisita@affrc.go.jp 

The influence of precipitation during the fruit growing season on the fruit quality and fruit juice sugar 

concentration was investigated over 7 years in Satsuma mandarin trees cultivated with the conventional 

thinning method and the intentional alternate bearing system. In this experiment, there was no difference 

between the two thinning methods in fruit quality and fruit sugar concentration. On the other hand, there 

were significant differences among years, and a negative correlation was observed between the amount 

of precipitation in August and the total sugar concentration at harvest time. Precipitation from July to 

November(x) decreased the glucose, fructose, and total sugar concentration(y) at harvest time. The 

correlation was shown by the equation y=-0.0046x 11.39. The sucrose concentration increased successively 

throughout the fruit growing season. On the other hand, the glucose and fructose concentration increased 

due to little precipitation in July and August but decreased with significant precipitation in September. Thus, 

the concentration of monosaccharides were influenced by the precipitation in the fruit growing season and 

greatly affected the total sugar concentration at harvest time. 


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S10P03 

Recover of plugged drippers in orange grove irrigation system using mechanical and chemical 

techniques 

Fachini E. 1 , Junqueira Franco A.C.B. 2 , and Galbiatti J.A. 3 

1 Centro Universitário de Araraquara (UNIARA), Agronomia, Brazil; 2 Aporte Técnico para o Desenvolviment (ATDA), Brazil; and 

3 Universidade Estadual Paulista (UNESP - FCAV), Engenharia Rural, Brazil. emfachini@terra.com.br 

A study was carried out to evaluate the effects of the combination of two techniques, chemical and 

mechanical on the dripper unclogged and uniformity distribution coefficient (UDC). The experiment was 

set up in Monte Azul Paulista city, in a commercial orange grove that was drip irrigated since 2002. The 

dripper were RAM type, with 3.5 L/h and the space between drippers was 0.85 m. The flowing evaluation 

from Keller and Karmeli (1975), modified by Deniculi et al. (1980) was used to evaluate 4 lateral lines (the 

first line, the lines located at 1/3, 2/3 of beginning of the block and the last line). In each line, 8 drippers 

were evaluated (the first, those located a 1/7, 2/7, 3/7, 4/7, 5/7, 6/7 from the beginning of the lateral line 

and the last one). Despite the UDC improved after all treatments applications, the drippers average flow 

increased when compared with the initial flow rate. The percentage of the drip plugged decreased to 0. 

The results showed that the treatments used were very effective in eliminating drip plugging but they 

modified the dripper flow rate. 

S10P04 

Effect of Sunred metabolic promoter and deficit irrigation on fruit quality of ‘Valencia’ oranges 

Massenti R., Barone F., Farina V., and Lo Bianco R. 

Università degli Studi di Palermo, Demetra, ITALY. roberto.massenti@unipa.it 

This study evaluated the effects of deficit irrigation and Sunred foliar metabolic promoter on fruit quality 

of adult ‘Valencia’ orange trees. Three irrigation strategies were imposed in spring 2011: i) irrigation with 

volumes corresponding to 100% of crop evapotranspiration applied to the entire root-zone (CI), ii) partial 

root-zone drying (PRD) with 50% of CI water applied to one alternated side of the root-zone, and iii) 

continuous deficit irrigation (DI) with 50% of CI water applied to both sides of the root-zone. Four trees in 

each irrigation treatment were sprayed 30 and 20 days before harvest with Sunred metabolic promoter 

containing phenylalanine, methionine, mono-saccharides and oxylipins from plant extracts. Climate and 

soil parameters were monitored continuously in the field; crop load and fruit quality were measured 

at harvest in May 2012. Fruit peel color was determined by digital image analysis. After adjusting for 

crop load, fruits of PRD and DI trees tended to be smaller but sweeter than those of CI trees. Regardless 

of irrigation, Sunred increased mainly TSS:acid ratio by lowering acidity. Average fruit peel color was 

similar in sprayed and control trees, but a smaller coefficient of variation indicated greater uniformity in 

fruit peel color. These preliminary results suggest that, regardless of the irrigation strategy, pre-harvest 

Sunred foliar sprays may improve internal fruit quality of ‘Valencia’ oranges by advancing and making 

more uniform fruit maturity. 

S10P05 

Foliar and root application of potassium nitrate and calcium nitrate to Citrus macrophylla 

seedlings under NaCl stress 

Navarro J.M., Andujar S., and Rodríguez Morán M. 

Instituto Murciano de Investigación y Desarrollo Agrario y Alimentario (IMIDA), Citricultura, Spain ringil_1@hotmail.com 

A growth chamber experiment was conducted to determine whether KNO 3 or Ca(NO 3 ) 2 could mitigate the 

adverse effects of salt stress on Citrus macrophylla seedlings. Six treatments were studied: C (control), S (30 

mM NaCl), KR (30 mM NaCl 10 mM KNO 3 , applied to the root system), KL (30 mM NaCl 10 mM KNO3, applied 

to the leaves), CaR [30 mM NaCl 10 mM Ca(NO 3 ) 2 , applied to root system] and CaL [30 mM NaCl 10 mM 

Ca(NO 3 ) 2 , applied to the leaves]. Although plant growth was unaffected by the saline treatment, salt injury 

in the form of leaf burn occurred. Salinity also affected other parameters, such as leaf gas exchange, which 


strongly decreased with the application of 30 mM NaCl. The potassium and calcium applications did not 

lead to increase photosynthesis rates. Neither the Ca nor the K treatment reduced the high Cl levels found 

in leaves, and leaf Na was only reduced by the CaR treatment. The calcium levels in leaves following the CaR 

treatment were higher than in C plants, whereas the CaL, KR and KL treatments led to lower Ca levels than 

in C plants. This was also the case with membrane stability, which increased with CaR but not with the foliar 

application of Ca or either of the K treatments. Cellular damage produced by salinity decreased with KL and 

both Ca treatments. These results suggest that, in general, the adverse effects of salinity on the nutritional 

and physiological response of C. macrophylla are not alleviated by the foliar treatments of Ca and K applied 

in this experiment. 

S10P06 

Effect of mulching and drip irrigation on Satsuma mandarin fruit quality in a volcanic ash soil 

Han S.G., Kim Y.H., Moon Y.E., and Kang S.B. 

Citrus Research Station, National Institute of Horticultural & Herbal Science, Rural Development administration, Korea. 

skhan@korea.kr 

The study aimed at improving water management in Satsuma mandarin (Citrus unshiu Cv. Okitsu Wase) 

cultivated with macro-porous film (MPF) mulching system in an open field environment under high 

precipitation regime. In those humid conditions, fruit often struggle to reach the desired total soluble 

solids (TSS). The MPF mulching systems was treated to repel water when it rains and water vapor releases 

from the soil. The mulching system was set up every early June before the onset of the rainy season 

and lasted up to the harvest period (November) from 2009 to 2011. Some observations indicated that 

TSS concentration increases from September to November, with the highest increasing rate observed in 

October. On the other hand, fruit titratable acidity (TA) decreased largely in September and October, with 

hardly decrease after November. Results show that fruit from trees cultivated under dry soil conditions 

had higher TSS and TA. In order to identify the optimal water supply after mulching, Satsuma mandarins 

were subjected to different watering treatments i) 0 (no irrigation), ii) irrigation application of 1.500 m 3 / 

ha, and iii) watering at 2.400 m 3 /ha. Irrigation started when fruit reached TSS 8.0 °Brix, and lasted until 

harvest. The control (no irrigation treatment) showed the highest TSS and also TA with 1.0% higher than 

the high quality standard (HQS; TSS≥12°Brix, TA≤1.0%). The 2.400 m 3 /ha treatment lead to fruit with TSS 

values lower than the HQS of 12.0 °Brix. The 1.500 m 3 /ha treatment showed higher TSS than 12.0 °Brix and 

TA lower than 1.0%. In summary, the high quality Satsuma mandarin could be produced by drip-irrigation 

with water supply at 1.500 m 3 /ha. 

S10P07 

Tree-to-tree variation in plant-based measurements as indicators of orange water status 

Motisi A. 1 , Continella A. 2 , Massenti R. 1 , and Romolo F. 1 

1 University of Palermo (DEMETRA), Italy; and 2 University of Catania (DISPA), Department of Agriculture and Food Science, Italy. 

acontine@unict.it 

A study was conducted in order to determine the sensitivity of measured indicators of the plant water 

status in a citrus orchard. In ten adult orange [Citrus sinensis] trees, grafted on sour orange (C. aurantium) 

rootstocks and drip irrigated every second day, sap flow by Granier TDP probes, leaf and xylem water 

potential, gas exchange and leaf and canopy thermal imaging were hourly monitored all over the day. 

The evaluations were performed during two separate clear-sky days with different environmental 

conditions, respectively in the summer and autumn seasons. Variations of environmental components 

(reference evapotranspiration, solar radiation, vapour pressure deficit and temperature) were recorded. 

Each measurement technique resulted effective to perceive continuous plant water status at the proper 

scale (tree and orchard level). In particular, transpiration rate, water deficit stress indicators, stomatal 

conductance and closure were related to diurnal changes in ET0 and net radiation. Tree-to-tree variations 

in the diurnal dynamics of tree gas exchange were evaluated to develop up-scaling rules of tree-level water 

consumption measurements. 


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S10P08 

Predicting the impact of the climatic variability in the necessities of watering of the grapefruit in 

the Island of the Youth in Cuba 

Cueto J.C., Pardo A.P., and Durán G.D. 

Instituto de Investigaciones en Fruticultura Tropical (IIFT), Grupo Difusión Tecnológica Isla de la Juventud, Cuba. despacho@iift.cu 

The expected increase in air temperature and the uncertainty related with the future predicted rainfall imply 

that irrigation might become a more important cultural practice for citrus trees located in humid areas. The 

objective of this work was to determine the present and future irrigation water needs for grapefruit citrus 

trees. The investigation was carried out in the conditions of the Island of the Youth (Cuba). The irrigation 

requirements for grapefruit culture during the period 1991- 2009 was calculated, and the predictions for 

2050 were also performed. The analysis of the potential evapotranspiration/rainfall (ETo/P) ratio showed that 

this value decreases near one from mid-June until the end of August. However, if the current climatic trends 

will continue during the decade 2020-2030, the ETo/P ratio might decrease to values well below one. In that 

case, irrigation will have to be supplied to the plantations. It is predicted an annual increment of the irrigation 

needs of 60 m³/ha. 

S10P09 

Effect of regulated deficit irrigation on vegetative growth, fruiting, stomatal conductance, leaf 

proline content and water use efficiency for Nules clementine grown in the Souss valley of 

Morocco 

Bagayogo S., El-Otmani M., El-Fadl A, and Benismail M. C. 

Institut Agronomique et Vétérinaire Hassan II, Complexe Horticole d’Agadir (IAV-CHA), Horticulture, Morocco. 

elotmani.mohamed@gmail.com 

Water scarcity is becoming a major problem for agricultural development in the Mediterranean area 

including Morocco. This research aims at developing irrigation strategies on citrus with the goal of reducing 

water supply without significant negative effects on yield or fruit parameters. The effect of four treatments 

on 5-year old Clementine trees (Citrus reticulata) grafted on Citrus macrophylla was assessed using drip 

irrigation and supplying different water amounts according to tree phenological stage for a total of 470 

mm of water [treatment T0 = crop water needs (ETc)], 580 mm [treatment T1 = 123% T0], 350 mm [T2 

= 77% T0] or 304 mm [T3 = 67% T0] applied during the 1 Feb. - 30 Oct. cropping period. Irrigation water 

was applied daily using emitters with different water flows and quantities supplied were based on local 

evapotranspiration and crop water needs (ETc). The duration of irrigation varied from 1 h in the winter 

time (supplying 0.9 mm/day to the least watered trees to 1.8 mm/day to the well irrigated ones) to 2 h 40 

min during hot summer days (supplying 1.8 to 3.7 mm/day, respectively). Results show that stressed trees 

have reduced vegetative growth but more flower buds and flowers. Stomatal conductance was positively 

correlated with water dosage whereas leaf proline content followed the inverse trend. These results and 

those on yield, final fruit size and quality (juice content, acidity, sugar content), and on water use efficiency 

(as kg fruit produced/m 3 of water used) will be presented and discussed in relation to the water deficit 

applied and its stage of application. 

S10P10 

Response of ‘Star Ruby’ grapefruit trees to deficit irrigation during different stages of fruit 

growth: effects on water relations, yield and fruit quality 

Pérez-Pérez J.G., Robles J.M., García-Oller M.I., and Botía P. 

Instituto Murciano de Investigación y Desarrollo Agrario y Alimentario (IMIDA), Department of Citriculture, Spain. 

juang.perez@carm.es 

Grapefruit is an emergent crop in the southeast of Spain in recent years. In spite of the fact that grapefruit 

is well adapted in semiarid regions, the irrigation necessities for fresh fruit production continue to be very 

high. The scarcity of water resources forces citrus growers to optimise water use by using deficit irrigation 


strategies. The aim of this work was to evaluate the sensitivity to deficit irrigation (DI) of different fruit growth 

stages of 14-year-old ‘Star Ruby’ grapefruit (Citrus paradisi Mac.) grafted on ‘Cleopatra’ mandarin (Citrus 

reshni hort. ex Tan.), regarding water relations, yield and fruit quality. The experiment was carried out in an 

experimental orchard located in Torre Pacheco (Murcia, southeastern Spain) during two years. There were 

four irrigation treatments: Control (100% ETc) and three DI treatments (50% ETc) applied only during different 

fruit growth stages: DI Ph-I (cell division), DI Ph-II (cell elongation) and DI Ph-III (final fruit-growth period, ripening, 

and harvest). The midday stem water potential (Ψ md ) of DI Ph-I and DI Ph-III were influenced by the rainfall 

regime in both years, whereas the Ψ md of DI Ph-III was decreased and remained lower during throughout the 

period. The main effects of both the DI Ph-I and DI Ph-III treatments were related with changes in fruit quality 

parameters, where DI Ph-I reduced the percentage of juice and DI Ph-III affected negatively the peel color when 

the water stress was moderate. However, the effects of DI Ph-II were more drastic, decreasing yield due to 

smaller fruits, altering fruit composition, increasing much more the titratable acidity than the total soluble 

solids, and reducing peel color, therefore delaying fruit maturation processes. Based on these results, the 

periods less sensitive to DI were Ph-I and Ph-III, which should be considered for future studies of regulated 

deficit irrigation under Mediterranean climates. 

S10P11 

Water relations and productivity of Natal orange plants under controlled deficit irrigation in São 

Paulo State, Brazil 

Pires R.C.M. 1 , Silva A.L.B.O. 1 , Ribeiro R.V. 1 , Quaggio J.A. 2 , Lima M.A.F. 1 , and Zani M.L. 3 

1Agronomic Institute (IAC), Ecophysiology and Biophysic - Irrigation, Brazil; 2Agronomic Institute (IAC), Soil nutrition, Brazil; and 

3Agricultural Engineering (FEAGRI - UNICAMP), Brazil. rcmpires@iac.sp.gov.br 

Agriculture is responsible for a large consumption of water in the world when compared to other economic 

activities. Deficit irrigation is one of the methods that in some cases can promote water savings, without 

reducing significantly the crop yield. The aim of this work was to evaluate the plant water relations and 

productivity of “Natal” orange trees grafted onto Swingle citrumelo under controlled deficit irrigation. The 

experiment was carried out in randomized blocks with five treatments and four replications from 2009 to 

2010. The treatments consisted of different irrigation regimes: T1 – optimal irrigation dose (100% of crop 

evapotranspiration - ETc), T2 - 80% of ETc, T3 - 60% of ETc, T4 - 40% of ETc and T5 - 20 % of ETc. The irrigation 

was applied by drip system. The effects of deficit irrigation on plant water relations were evaluated by 

measuring leaf transpiration and stomatal conductance. Both physiological variables were favoured in T1, T2 

and T3. The yield and number of fruits were higher when applied 100%, 80% and 60% of ETc, in T1, T2 and T3, 

respectively. Our data revealed that a significant amount of water (~40%) can be saved with deficit irrigation 

without negative impacts on citrus yield and leaf water relations. 

S10P12 

Responses of Clementina de Nules citrus trees to deficit irrigation under different rootstocks. 

Tree performance and fruit quality 

Ortega J. 1 , Molina M.D. 2 , Intrigliolo D.S. 1 , de Miguel A. 2 , Bonafé C. 2 , Valero J.L. 2 , Peiró E. 2 , and Forner-Giner M.A. 3 

1Instituto Valenciano Investigaciones Agrarias (IVIA), Sustainable Agriculture Center, Spain. 2Instituto Valenciano Investigaciones 

Agrarias (IVIA), Technology Transfer Center, Spain. 3Instituto Valenciano Investigaciones Agrarias (IVIA), Citriculture, Spain. 

intrigliolo_die@ivia.gva.es 

Rootstock tolerance to soil water deficit has been evaluated in a field trial located in Valencia (Spain). 

Clementina de Nules (C. clementina hort. ex Tan.) were grafted either on Carrizo citrange [Citrus sinensis (L.) 

Osb. x Poncirus trifoliata (L.) Raf.], the most common citrus rootstock in Spain, or Forner-Alcaide 5 (a hybrid 

of C. reshni hort. ex Tan. x P. trifoliata) recently released by the citrus breeding program of the Instituto 

Valenciano de Investigaciones Agrarias. Trees were planted in 1998 and the irrigation regime trial started in 

2008 and lasted until 2011. Trees were submitted to either full irrigation (Control) or deficit irrigation (DI, 

watering at 60% of the Control regime). During the summer period, plant water status and leaf gas exchange 


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were evaluated. Yield, fruit quality and tree size were determined every year. Citrus fruit disorders were 

evaluated only in the last experimental season. There was a cumulative effect over years of deficit irrigation 

on tree growth. In both rootstocks, after five years, DI reduced tree canopy growth by 50%. Yield was only 

reduced by DI in the last experimental season by 12-20%. Juice content, acidity and total soluble sugar 

concentration were affected by both the rootstock type and the irrigation regime. Puffing of Clementine fruits 

was not affected by the irrigation regime. Creasing was only increased by DI in the Carrizo citrange rootstock 

while in the Forner-Alcaide 5 the irrigation regime did not affect this fruit disorder. 

S10P13 

Root distribution of orange trees under two different drip irrigation systems 

Fachini E. 1 , and Galbiatti J.A. 2 

1 Centro Universitário de Araraquara (Uniara), Agronomia, Brazil; and 2 Universidade Estadual Paulista (UNESP), Engenharia Rural, 

Brazil. emfachini@terra.com.br 

A study was carried out in two orange groves of irrigation and fertirrigation with a drip irrigation system to 

compare root distribution of trees under different management after four years. The experiment was set 

up on the commercial grove in Palestina and Altair, State of São Paulo, Brazil. Trees of Natal sweet oranges 

on Cleopatra mandarin were 21-year-old. The Altair grove was established with two drip lines per row of 

trees, and the Palestina grove with one drip line. The irrigation management in both places used the class 

pan evapotranspiration. Soil core samples were collected 1.0, 1.5 and 2.0 m from the canopy edge, either 

along the tree row or between rows at the 0-15, 15-30, 30-45, and 45-60 cm soil depth layers. The method of 

weight of root dry mass was used to estimate distribution in the soil. The distribution of roots along the tree 

row was 3.8 times bigger in the Palestina grove compared to the Altair one. The root distribution in between 

rows was 1.4 times bigger in Palestina than in Altair. In this study, the irrigation with one drip line per row of 

orange trees limits the root system growth. The distribution of roots within a smaller volume of soil could be 

important to increase efficiency of absorption of water and nutrients by trees. 

S10P14 

The effect of herbicide treatments on soil nutrient availability and plant nutritional status in a 

citrus garden 

Wu C.Q. 1 , Liao C.X. 2 , Ou Y. 1 , and Xie Y.H. 1 

1 Chongqing Academy of Agricultural Sciences (CAAS), Fruit Research Institute, China; and 2 Chongqing agriculture commission (CAC), 

China.. cqxieyh@hotmail.com 

This paper reports the effects of weed control with herbicides on the nutritional status of Licheng [Citrus 

sinensis]. Tested treatments were: control (CK) #1 (41% Nong pan glyphosate IPA salt, 200x diluted) #2 

(41% Chun duoduo glyphosate IPA salt 200x diluted) #3 (10% Hai ning glyphosate 30x diluted) # 4 (30% 

Feida glyphosate 150x diluted) #5 (Paraquat 200x diluted). Results showed the content of total nitrogen in 

the soil did not vary for herbicides compared with CK. On the contrary, the content of available phosphorus 

in soil increased 2.0%~15.3% compared to the CK while the effect of treatments #1 and #2 were similar. 

Herbicides could decrease the content of available iron in soil, since effects of treatments #2 and #3 showed 

a remarkable difference between each other. At the late stage of herbicide use, the manganese content of 

soil became slightly higher than CK with no noticeable difference except for treatment #3. Otherwise, the 

content of zinc decreased in all herbicide treatments. We also found that total leaf iron decreased 1.9% to 

3.7% in the CK compared to treatments # 2, #3 and #4. Herbicide treatments #1, #2 and #4 decreased zinc 

content of leaves by 2.3% to 3.7% compared with the CHK. The manganese leaf content could be increased 

to an extent of 2.3% to 5.7% in response to herbicide treatments. The nitrogen leaf content behaved was 

different in treatments #3 and #4. The content of phosphorus did not vary in all treatments. Therefore, 

herbicide use can decrease the content of available iron and zinc to plants in spite of its effectiveness in 

weed control. 


S10P15 

Efficiency of zinc (68Zn) fertilizers applied to the soil with citrus 

Boaretto R.M. 1 , Hippler F.W.R. 1 , Quaggio J.A. 2 , Boaretto A.E. 3 , Abreu Jr. C.H. 3 , and Mattos Jr. D. 1 

1 Instituto Agronômico (IAC), Centro de Citricultura Sylvio Moreira, Brazil; 2 Instituto Agronômico (IAC), Centro de Solo e Recursos 

Ambientais, Brazil; and 3 Universidade de São Paulo (USP/ CENA), Centro de Energia Nuclear na Agricultura, Brazil. 

boaretto@iac.sp.gov.br 

The supply of zinc (Zn) affects citrus production in Brazil, because of inherently low nutrient availability 

and high predicted interaction with soil colloids. Therefore, the form of Zn application and fertilizer sources 

are important for nutrient management of orchards. The aim of this study was to evaluate the effect of Zn 

fertilizers applied to the soil and the nutrient absorption by citrus trees. The experiment was carried out in a 

greenhouse using one-year-old potted orange trees. The plants were grown in two different textured soils (181 

and 644 g kg -1 of clay) that received 1.8 g tree -1 of Zn either as ZnO or ZnSO 4 . The Zn fertilizers were enriched 

with the stable 68Zn isotope, which allowed estimation of Zn absorption by roots and its partitioning into the 

orange trees. The Zn fertilization increased nutrient availability in the soil and content in the orange trees. 

The ZnSO 4 was the most efficient fertilizer source providing highest accumulation of 68 Zn in the tree parts, 

with 70% of the total accumulated found in the roots. The Zn in the plant derived from the labelled fertilizer 

was higher in the stem and branches than in the leaves. The application of Zn in the sandy loam soil provided 

greater dry matter production, accumulation of Zn and enzymatic activity of the superoxide dismutases in the 

trees. The application of Zn in the clayey soil was less effective to increase nutrient availability to the orange 

trees, especially when the ZnO was applied. 

S10P16 

Interaction of magnesium in calcium uptake in young citrus trees 

Martínez-Alcántara B., Quiñones A., Alcayde E., and Legaz F. 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Citriculture and Vegetal Production, Spain. legaz_fra@gva.es 

Calcium is a macroelement involved in numerous physiological processes in plants, such as cell division and 

growth, it is part of the structure of cell walls and membranes, and together with the magnesium participates 

in the activation of metabolic enzymes of proteins and carbohydrates. There are numerous studies on Ca 

conducted in the plant-soil system, however, no information is available on its absorption and distribution 

among different plant organs. In this sense, the use of the stable isotope 44 Ca as a tracer becomes a valuable 

tool since it allows to accurately determine the fate of the element applied in the plant-growing medium. Ca 

absorption by plant roots depends on several factors, among which are the availability of this nutrient in the 

culture medium and the presence of antagonists such as magnesium. The main objective of this study was to 

evaluate the effect of different Mg concentrations (0.5, 1, 2, 4, 8 mM) in the growing medium on Ca uptake 

and its distribution among different organs in young plants of citrus grown during one month in controlled 

conditions (growth chamber) using 44 Ca as a tracer. Increasing concentrations of Mg significantly reduced 

44 Ca content in harvested plants, and hence the Ca-uptake efficiency. 

S10P17 

Study on the relationship between fruit quality, soil nutrient availability and tree nutritional 

status 

Lu X.P., Huang C.N., Xiao Y.M., Nie Q., Zhao X.L., and Xie S.X. 

College of Horticulture and Landscape (CHL), Hunan Agricultural University, China. puninglu@126.com 

Ponkan is one of the two important mandarin varieties in China because of superior fruit yield and quality, 

and fresh market value. Aiming to guide precise fertilization and increasing grower income, the relationship 

between fruit quality, and soil and tree nutrient status was studied within five of the main Ponkan production 

areas: Yongshun county (YS), Baojing county (BJ), Jishou city (JS), Luxi county (LX) and Xinhua county (XH). 

The results showed that soil pH value of five areas ranged from 4.4 to 5.4. Water coefficient was significantly 

higher in XH than that in the other areas. Soil organic matter in JS and LX was lowest and also lower than the 


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optimum value. Available nitrogen content was highest in XH and the lowest in JS, but all of the areas were 

lower than the optimum. There was similar trend for leaf nitrogen content. Phosphorus contents in soil and 

leaves varied in different areas; tree leaf phosphorus from XH and BJ reached the optimum value, while others 

were lower than that. Soil potassium was the lowest in JS and LX orchards, while leaf potassium content in all 

area orchards was lower than the optimum value. Magnesium and calcium availability in soil were high in all 

areas, but very low in leaves. Zinc in all areas reached the optimum value in both soil and leaves. Data of fruit 

quality analysis indicated that Ponkan fruits from five areas had similar fruit weight, TSS and titratable acid, 

while fruits from XH presented the highest sugar and lowest acid contents. 

S10P18 

Boron supply affects growth of citrus and correlates with hydraulic conductivity and gas 

exchange of rootstock varieties 

Mesquita G.L., Mattos Jr. D., Ribeiro R.V., Boaretto R.M., and Quaggio J.A. 

Instituto Agronômico (IAC), Tecnologia de Produção, Brasil. gelm_1@hotmail.com 

Boron (B) nutrient disorders cause malfunction of the vascular cambium and growth inhibition. The 

nutrient distribution and its concentration in the leaves of citrus vary among rootstocks, mainly due to the 

characteristics of roots and water transport in the plant. The objective of this study was to evaluate the 

effect of B availability on tree growth, and correlate it to hydraulic conductivity and gas exchange of two 

citrus rootstock varieties. The experiment was conducted in nutrient solution in a factorial design with 1-yrold 

Valencia orange trees on two rootstocks: Swingle citrumelo (SW) and Sunki mandarin (SK) supplied with 

three B levels: poor, adequate and excessive (0, 0.5 e 2.5 mg L -1 of B). The hydraulic conductivity of the plant 

(KL) and gas exchange were measured 130 days after beginning the experiment, when plants were collected 

and separated into roots, stems and leaves for dry mass estimations. The dry mass production, KL and CO 2 

assimilation (A) were differentially affected by the levels of B. Growth and KL increased linearly with B rates 

in the nutrient solution for trees on SW [81.3 g per plant and 3.16 mmol(H2O) m –2 s –1 MPa –1 , respectively], 

whereas A was maximum with the adequate nutrient level (3.49 µmol m -2 s -1 ). Excess B caused significant 

injuries on trees on SK, which showed optimum plant growth, KL and A with the adequate B level [53.3 g per 

plant; 6.02 mmol(H 2 O) m –2 s –1 MPa –1 , and 6.05 µmol.m -2 .s -1 , respectively]. 

S10P19 

Silicon uptake in citrus and the validation of an analytical method 

Vahrmeijer J.T. 1 , Asanzi N.M. 2 , and Taylor N.J. 2 

1Citrus Research Inernational (CRI), Fruit Production and Quality, South Africa; and 2University of Pretoria (UP), Plant Production and 

Soil Science, South Africa. jtv@up.ac.za 

The importance of silicon as a beneficial element for improving yield and quality of many crops, including citrus, 

is well-known. However, whilst analytical methods to determine Si in plant material have been developed and 

the uptake of Si in other plants is well documented, there is limited information on the uptake and analysis 

of Si in citrus. Therefore, experiments were conducted to validate an analytical method for Si and to assess 

the uptake of Si in citrus. Microwave-assisted digestion was used for Si extraction and the Si concentration 

was determined with an induced couple plasma optical emission spectrum (ICP-OES), which was compared 

to the standard colorimetric method. Silicon uptake experiments in citrus varieties (Valencia and Clementine) 

were conducted in winter and summer with two Si formulations, potassium silicate and silicic acid and was 

applied to the roots (0, 75 and 150 mg kg -1 ) and as a foliar spray (0, 100 and 500 mg L -1 ). A correlation of 98% 

was found between the ICP-OES and the standard colorimetric method.- The uptake study results showed no 

significant differences (P≤0.05) in Si content for different Si formulations and citrus varieties, but Si content in 

citrus leaves increased significantly (P≤0.01) with maturity. Silicon absorption increased significantly (P≤0.05) 

with application rate and Si content in the leaves was significantly higher (P≤0.05) when applied to the roots, 

than when applied to the leaves. Si uptake was also significantly higher in summer than in winter. 


S10P20 

Phosphorus deficiency decreases nutrient use efficiency of citrus 

Zambrosi F.C.B., Mattos Jr. D., Quaggio J.A., and Boaretto R.M. 

Instituto Agronômico (IAC), Solos, Brasil. zambrosi@iac.sp.gov.br 

The evaluation of the effects of P availability on the efficiency of nutrient absorption and utilization by citrus 

rootstocks is required to extend the knowledge on plant responses to P deficiency. Thus, seedlings of citrus 

rootstocks ‘Rangpur’ lime, ‘Swingle’ citrumelo, ‘Cleopatra’ and ‘Sunki’ mandarins were grown on nutrient 

solution with 0.0125; 0.05; 0.2 and 0.8 mmol L-1 of P. After 100 days of P treatments, the rootstocks were 

harvested and then separated into leaves, stem and roots to estimate plant dry weights, and N, K, Ca, Mg, 

S and B concentrations. The nutrient accumulation by the citrus rootstocks was proportional to P supply 

in the nutrient solution. Regardless of treatment, the following pattern of nutrient accumulation by the 

rootstocks was observed: ‘Rangpur’ lime > ‘Swingle’ citrumelo > ‘Sunki’ mandarin > ‘Cleopatra’ mandarin. The 

lowest P concentration in the nutrient solution significantly decreased the efficiency of nutrient absorption 

and utilization compared to 0.2 and 0.8 mmol L-1 of P. The ‘Rangpur’ lime was the most efficient rootstock 

in nutrient utilization for growth, while ‘Swingle’ citrumelo was the least efficient in nutrient absorption. 

The results demonstrate that low-P availability decreased the accumulation, efficiency of absorption and 

utilization for growth of N, K, Ca, Mg S and B by the plants, suggesting that the adequate management of P 

fertilization is critical to improve nutrient use efficiency in citrus orchards. 

S10P21 

Enhancement yield, fruit quality and nutritional status of Washington Navel orange trees by 

application of some biostimulants 

El-Shazly S.M. 1 , and Mustafa N.S. 2 

1 Faculty of Agriculture, Alexandria University, Alexandria, Egypt. 2 Agricultural and Biological Division, National Research Center, Cairo, 

Egypt. samyshazly55eg@yahoo.com 

The effect of biostimulants [potassium humate, yeast extract and amino green II (amino acids mixture)] 

on yield, fruit quality and nutritional status of Washington Navel orange trees were evaluated under field 

conditions. Potassium humate was applied at 10 and 20 g/tree as soil application. In addition, yeast extract 

at 0.2 and 0.4% and amino green II at 0.25 and 0.5% were applied as foliar application. The obtained data 

revealed that all biostimulants increased total yield compared to control. The highest yield was obtained 

with trees received potassium humate at 20 g/tree. Fruit weight, fruit juice %, total soluble solids (TSS), total 

sugars and vitamin C contents were markedly increased with biostimulants treatments compared to control. 

Moreover, high values of such characters were obtained with trees treated with potassium humate at 20g/ 

tree and active dry yeast at 0.4%. Biostimulants treatments enhanced leaf chlorophyll content and leaf mineral 

contents of N, P, K, Ca and Mg. It was concluded that biostimulants treatments had a promotional effect on 

yield, fruit quality and nutritional status of Washington Navel orange trees. In this respect, potassium humate 

at 20 g/tree and active dry yeast at 0.4% were considered promising treatments. 

S10P22 

Calcium, magnesium and potassium levels in the soil and in the leaf of orange trees on different 

rootstocks and soil conservation systems in the northwest of Paraná State, Brazil 

Gil L. G. 1 , Auler P. A. M. 2 , and Pavan M.A. 1 

1 Instituto Agronônico do Paraná (IAPAR), Área de Solos, Brasil; and 2 Instituto Agronônico do Paraná (IAPAR), Área de Fitotecnia, Brasil. 

lggil@iapar.br 

This study aimed to determine the effects of soil preparation, Brachiaria brizantha mowing, and rootstocks on 

soil nutrient availability and leaf Ca, Mg and K contents of orange trees, on a Typic Haplorthox originated from 

the Caiua Sandstone. The experimental plots were defined by soil preparation: no-tillage (NT), strip-tillage 

(ST) and conventional tillage (CT); the subplots by mowing management between tree rows: conventional 

(CM) and mulching (MM), and the subsubplots by rootstocks: Rangpur lime and Cleopatra mandarin. Leaf 


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and soil samples (0-10,10-20, 20-30 and 30-40 cm depth layers, along tree rows and between rows) were 

collected from 2005 to 2009 for chemical analyses. Leaf Ca content was higher for the CM and for the 

Cleopatra mandarin trees. Leaf K was higher for the MM and for the Rangpur ones. Ca and Mg in the 0-10 cm 

soil layer between rows were higher for NT, and in the lower layers the contents were higher for CT. The MM 

increased exchangeable K availability in all soil depths, and this management reduced the Ca content down to 

the 30 cm depth layer. The establishment of orange orchards under the NT system did not cause detrimental 

effects on soil fertility. On the contrary, it favored the increase of Ca and Mg in the top soil layer. The MM was 

important not only for the maintenance of adequate K levels in the soil but also for the improvement of the 

K recycling in the soil system. 

S10P23 

Response of clementine citrus to foliar potassium fertilization: Effects on fruit production and 

quality 

Hamza A1 , El Guilli M2 , Bamouh A3 , Zouahri A4 , Bouabid R5 , and Lfadili R6 . 

1Institut National de la Recherche Agronomique (INRA), Agronomy, Morocco; 2Institut National de la Recherche Agronomique 

(INRA), Phytopthology, Morocco; 3Institut Agronomique et Vétérinaire Hassan II (IAV Hassan II), Plant Production, Protection and 

Biotechnology, Morocco; 4Institut National de la Recherche Agronomique (INRA), Soil Science, Morocco; 5Ecole Nationale d’Agriculture 

de Meknès (ENAM), Soil Science, Morocco; and 6Institut Agronomique et Vétérinaire Hassan II (IAV Hassan II), Agronomy, Morocco. 

hamza.abdelhak@gmail.com 

Clementine “Cadoux” (Citrus reticulata Blanco) is a citrus fruit that is well appreciated by consumers. However, 

this cultivar tends to produce fruits of small to medium size that are less accepted commercially. In this study, 

we evaluated the effects of various rates and frequencies of foliar potassium fertilization, as either potassium 

nitrate (KNO 3 ) or potassium sulfate (K 2 SO 4 ), on fruit production (fruit size, weight and yield) and quality 

parameters (skin thickness, firmness, color index, maturity index, juice content, acidity and total soluble sugars). 

Application rates of tested foliar fertilizers were 5% and 8% KNO 3 , 2.5% and 4% for K 2 SO 4 , applied either two 

or three times during fruit growth on orchards of three planting densities (D1: 6 x 6 m, D2: 5 x 6 m and D3:- 6 x 

3.5 m). The levels of potassium in leaves of clementine var. Cadoux increased by 40% two weeks after the last 

foliar potassium application. Fruit weight increased with potassium application rate and frequency. Potassium 

fertilization treatments in three foliar applications showed the best percentages of fruits of extra size class, 

whatever the source of potassium (KNO 3 or K 2 SO 4 ) or plant density. Foliar applications of potassium increased 

fruit color, firmness and rind thickness. Fruit juice content, acidity and total soluble sugars were slightly increased 

by foliar potassium application. Raising potassium concentration and the number foliar applications increased 

tree fruit production. In terms of efficiency of foliar potassium fertilizers, 4% K 2 SO 4 in three applications resulted 

in a maximum gain of fruits per kg of foliar fertilizer. 

S10P24 

Impact of biostimulant substances on growth of Washington Navel orange trees 

Mustafa N.S. 1 , and El-Shazly S. M. 2 

1 National Research Center, Cairo (Citrus nutrition), Pomology, Egypt; and 2 Pomology Department, Faculty of Agriculture, Alexandria 

University, Alexandria, Egypt. nabilhotline@yahoo.com 

In a field experiment, Washington navel orange trees were treated with three biostimulants [potassium 

humate, active dry yeast and amino green (amino acids mixture)] to study the effect of these substances on 

vegetative growth and leaf contents of Na and Cl. Potassium humate was applied at 10 or 20 g/tree to the soil. 

In addition, yeast extract at 0.2 or 0.4%, and amino green II at 0.25 or 0.5% were applied to the plant leaves. 

The results showed that tree height, leaf area, leaf fresh and dry weights and volume index were positively 

affected by the biostimulants treatments. Greater vegetative growth of trees was achieved with potassium 

humate > active dry yeast > amino green. Data also demonstrated that biostimulant treatments significantly 

decreased leaf Na and Cl contents compared to untreated control trees. Therefore, such substances (especially 

potassium humate) can be used to reduce negative impacts of salinity in soil or irrigation water. In general, 

biostimulants substances had a beneficial effect on growth performance and leaf contents of Na and Cl of 

Washington navel orange trees. 


S10P25 

Foliar nutrition with macronutrients for Valencia orange and Murcott tangor trees 

Rodríguez V.A. 1 , Alayón Luaces P. 1 , Píccoli A.B. 2 , Chabbal M.D. 3 , Giménez L.I. 4 , and Martínez G.C. 2 

1 Facultad de Ciencias Agrarias - UNNE (FCA - UNNE), Producción Vegetal, Argentina; 2 Facultad de Ciencias Agrarias - UNNE (FCA - 

UNNE), Física y Química, Argentina; 3 Facultad de Ciencias Agrarias - UNNE (FCA - UNNE), Producción Vegetal, Argentina; and 4 Facultad 

de Ciencias Agrarias - UNNE (FCA - UNNE), Cálculo Estadístico y Biometría, Argentina. cocorodriguez@live.com.ar 

In order to achieve quick tree responses, opportune foliar fertilization is used complementary to soil nutrition. 

The objective of this study was to analyze the effects of different doses of foliar fertilizers on ‘Valencia late’ 

sweet orange and ‘Murcott’ tangor. Field experiments were done during three seasons in commercial 

orchards in Corrientes, Argentina, on complete block designs with four replications and experimental plots 

of four trees. Tested treatments were: T1 control; T2 N (12%) 2 L ha -1 ; T3 N (12%) 4 L.ha -1 ; T4 N (9%) and P 

(2.6%) 2 L.ha -1 ; T5 N (9%) and P (2.6%) 4 L ha -1 ; T6 N (9.3%), P (2.6%) and K (2.1%) 2 L ha -1 ; T7 N (9.3%), P 

(2.6%) and K (2.1%) 4 L ha -1 ; sprayed three times per season, at pre-flowering, full flowering and last summer 

sprouting. Leaf concentrations of N, P and K were determined in leaves of fruiting branches obtained in 

autumn. At harvest, total fruit production was measured and diameter, percentage of juice, soluble solids 

content, acidity and ratio were determined on a sample of 40 fruits per plot. Variance analysis and Duncan 

test were performed. In ‘Valencia late’, compared to the control, all sprayed treatments increased P foliar 

concentration. Treatment T7 increased yield but fruits had smaller diameter. In ‘Murcott’, fertilizer treatments 

increased fruit yield compared to the control, with higher production in T7 and T6 plots; T7 increased P foliar 

and decreased total soluble solids in juice compared with control. Foliar fertilization with macronutrients 

allows increased fruit production of ‘Valencia late’ sweet orange and ‘Murcott’ tangor. 

S10P26 

Effects of nutritional trunk injections on sweet orange production 

Martínez G.C. 1 , Alayón Luaces P. 2 , Yfran Elvira M.M. 1 , Chabbal M.D. 2 , Mazza S.M. 3 , and Rodríguez V.A. 2 

1 Facultad de Ciencias Agrarias - UNNE (FCA - UNNE), Física y Química, Argentina; 2 Facultad de Ciencias Agrarias - UNNE (FCA - UNNE), 

Producción Vegetal, Argentina; and 3 Facultad de Ciencias Agrarias - UNNE (FCA - UNNE), Cálculo Estadístico y Biometría, Argentina. 

cocorodriguez@live.com.ar 

The objective of this work was to determine the effect of nutritional trunk injections (NI) of N (0.80%), P 2 O 5 

(0.80%), K 2 O (0.70%), CaO (0.07%) and MgO (0.25%) on fruit yield and quality of “Valencia late” orange trees 

in Corrientes, Argentina. Field experiments were conducted during three years (from 2008/09 to 2010/11 

harvest seasons) with NI applications to each side of tree´s trunk, at 20 cm above soil surface. The treatments 

consisted of soil fertilization (50% spring and 50% autumn) with: (1) 1.5 kg plant -1 of a 15-6-15-6 NPKMg 

formula utilized in the region (half dose, HF); (2) HF plus NI in spring; (3) HF plus NI in spring and summer; 

(4) HF plus NI in spring, summer and autumn, and (5) 3.0 kg plant -1 of 15-6-15-6 (full dose). Statistical design 

was a randomized complete block with four replications, with two plants per plot used for evaluation of 

treatment effects. Concentrations of N, P, K, Ca and Mg were determined in leaves of fruiting branches 

obtained in autumn. Total fruit production was measured, and diameter, percentage of juice, soluble solids 

content, acidity, ratio and juice color were determined on a sample of 40 fruits per plot at harvest. Variance 

analysis, Duncan test and principal component analysis were conducted for quantitative variables, whereas 

Kruskal Wallis test was performed for color. The treatments did not affected fruit quality. However, treatment 

4 increased 26.5% fruit yield compared with same dose of soil application (treatment 1). 

S10P27 

Influence of reduced rate of application of phosphorus and potassium fertilizers on soil and fruit 

quality in a Satsuma mandarin orchard 

Yoshikawa K.Y. 1 , Nakamura A.N. 1 , Baba A.B. 2 , and Kusaba S.K. 3 

1 Shizuoka Prefectural Research Institute of Agriculture and Forestry (SPRIAF), Fruit Research Center, Japan; 2 Shizuoka Prefecture 

(SP), Community and Environmental Affairs Department, Japan; and 3 National Agriculture and Food Research Organization (NARO), 

Institute of Fruit Tree Science, Japan. kiminori1_yoshikawa@pref.shizuoka.lg.jp 

The influence of reduced rates of application of phosphorus and potassium fertilizers on fruit quality and 

soil in a Satsuma mandarin (Citrus unshiu Marc.) orchard was investigated. Thirteen-year-old trees grown 


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on gray upland soil were used. Phosphate and potassium fertilizers were applied at rates of 0% (PK0), 50% 

(PK1), and 100% (PK2), with respect to the conventional amount of fertilizers (P 2 O 5 : 120 kg ha -1 , K 2 O: 240 kg 

ha -1 ). Reduction in the rate of application of phosphate and potassium fertilizers had no influence on the 

sugar and acid contents of the fruits. In addition, reduction in the rate of phosphate application had no 

influence on the available phosphoric acid content in the soil. Phosphorus concentration in the leaves of PK0 

was lower than that of PK1 and PK2; however, the concentration was within the standard range for nutritional 

diagnosis- The exchangeable potassium content in the soil of PK0 was lower than that of PK2. Potassium 

concentration in the leaves showed no change in all the treatments. These results show that reduction in the 

rate of phosphorus fertilizer application is possible in Satsuma mandarin orchards to prevent accumulation 

of available phosphoric acid in the soil. Since the level of exchangeable potassium in the soil decreased, it is 

necessary to judge the reduction in the rate of potassium fertilizer application by performing soil diagnosis. 

S10P28 

Potassium leaching from young lysimeter-grown orange trees 

Boman B. J. 1 , and Battikhi A.M. 2 

1University of Florida (UFL), Indian River Research and Education Center, USA; and 2University of Jordan (UJ), Soil Science, Jordan. 

bjbo@ufl.edu 

A study was conducted at University of Florida Indian River Research and Education Center to determine the 

effects of different fertilizer forms on the leaching of potassium to groundwater in the sandy soils common 

to the area. Lysimeters constructed from polyethylene tanks were filled with Oldsmar fine sand soil. A single 

‘Midsweet’ orange on Carrizo citrange rootstock tree was planted in each lysimeter. Fertilization treatments 

included conventional applications of dry-soluble fertilizer at 6-week intervals, weekly fertigation applications, 

and single annual applications of two different controlled release materials. Irrigation (by microsprinklers) and 

drainage volumes measured with totalizing flow meters were collected weekly for two and a half years. Trees 

fertilized with controlled release products achieved equivalent growth to trees fertilized by the dry soluble 

materials and to those fertigated, even though the controlled-release treatment trees received only 44% of N 

and K as the other treatments. The amount of K leached averaged 39% (fertigated), 45% (controlled release), 

and 56% (dry soluble) of that applied. The total K leached with the controlled release fertilizer treatments 

was approximately one-half that of the fertigated trees and one-third that of the dry broadcast treatments. 

Leaching of K was found to be directly related to the weekly rainfall rate. 

S10P29 

Effect of organic fertilization on soil organic matter and on root apparatus of citrus trees 

Trinchera A. 1 , Torrisi B. 2 , Allegra M. 2 , Rinaldi S. 1 , Rea E. 1 , Intrigliolo F. 2 , and Roccuzzo G. 1 

1 Centro di ricerca per lo studio delle Relazioni tra Pianta e Suolo (CRA-RPS), ITALY; and 2 Centro di ricerca per l’Agrumicoltura e le 

Colture Mediterranee (CRA-ACM), ITALY. francesco.intrigliolo@fastwebnet.it 

The aim of this work was to verify the effect of organic fertilization on soil organic matter and on root apparatus 

of mature orange trees [Citrus sinensik] ValenciaeLate, grafted on C. aurantiu., in citrus orchard organically 

managed for 15 years. In a randomized block experimental design, compost from “pastazzo” (mixture of 

citrus pulp and skin), poultry manure, bovine manure, compared to a mineral fertilizer, were applied yearly to 

the soil (the same N/plant/year). For each plant, an equal volume of soil was sampled at the same distance 

from the trunk determining, in the sampling areas, the root density (roots weight/soil volume). The root 

biomass was then separated into primary and secondary roots, calculating the related fresh weight and dry 

matter. Representative young roots were selected and analyzed by electron scanning microscopy (SEM). As 

far as soil characterization concerns, the TOC%, TEC%, HA% and FA% were determined and then the related 

HR% and DH% were calculated. Results showed that organic fertilization, when compared to the mineral one, 

determines not only an improvement of soil organic matter content and humification parameters, but also 

an increase of root biomass. The SEM analysis evidenced that organic fertilizers induced the appearance of 

adventitious buds on the terminal portions of the roots, an improved regularity of the elongating meristematic 

cells an, an increase of the production of root mucigel. 


S10P30 

Use of plant-soil-atmosphere sensors on a young Clementine mandarin orchard under regulated 

deficit irrigation to monitor changes in water relations for better irrigation scheduling 

El-Otmani M., El-Fadl A., and Benismail M.C. 

Institut Agronomique et Vétérinaire Hassan II, Complexe Horticole d’Agadir, BP: 728 (IAV-CHA), Horticulture, Morocco. 

elotmani.mohamed@gmail.com 

Water availability for agriculture irrigation is becoming scarce in the Mediterranean Basin. Citrus orchards 

use as much as 1 000 m 3 ha -1 , if not more in situations where flood irrigation is still a common practice. 

However, producers are looking for ways and strategies to save as much of the resource as possible. For this 

reason, young Clementine orchard, planted in 2007 in the area of Agadir, Morocco receiving about 200 mm 

of rain per year, was used to test a regulated deficit irrigation strategy (RDI) supplying a combination of 100%, 

75% or 50% of crop evapotranspiration ((ETc) at different stages of fruit development on tree vegetative 

and reproductive development. Reference ETo was calculated using parameters obtained from a compact 

weather station installed near the orchard. To monitor soil water statul, Watermark and FDR probes were 

used. Tree Water relations were evaluated using 1) LVDT sensors for measuring tree diameter microvariations, 

2) leaf water potential, 3) trunk sap flow and 4) stomatal conductance. Trunk diameter, sap flow and stomatal 

conductance were significantly affected by climatic conditions and soil humidity. RDI had an effect on root 

and canopy development but effect on fruiting varied among years with the well irrigated trees tending to 

have more fruits at harvest. The results are discussed in relation to water economy and water use efficiency 

as well as in relation with the accuracy of the sensors and the possibility of their use in irrigation scheduling. 


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Session 11 

CULTURAL PRACTICES 

AND MECHANIzATION 

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S11O01 

New method of citrus grafting by the use of laboratory tape (top budding) 

Kitamura M. 1 , Caisley J. 2 , Sakaki H. 1 , Fujita K. 1 , and Takahara T. 1 

1 Kumamoto Prefectural Agricultural Research Centre, Institute of Fruit Tree Science, Japan; and 2 Japan Concept Ltd., UK. 

jonathan.caisley@japan-concept.co.uk 

For propagation of citrus trees in Japan, Bench Grafting is used in spring, and Budding in autumn. Both 

methods have drawbacks, with high worker skill required for Bench Grafting, and a long process needed 

for Budding, due to the need to return later in the season to remove foliage left above the budded area. 

Therefore, we examined Top Budding (TB), a simple new method not requiring expert grafting skills and 

suitable for mass tree cultivation. TB is used from spring to early summer when the sap of the rootstock 

is flowing and bark can easily be removed for budding. Buds taken in Feb / March were used and inserted 

by standard T-budding. The rootstock was cut completely 5 cm above ground, removing all upper foliage 

(unlike the existing method where the foliage is kept). After grafting, the bud union area was totally sealed 

with water tight, air porous laboratory film (brand name: Buddy Tape) to prevent dehydration. TB and 

Bench Grafting showed similar survival rates, but bud break of the scion with TB was slightly later than 

for Bench Grafting. Growth for Bench Grafting was quicker than for TB in early stages, but by the end of 

the growing period, both grafts had equal growth. Operation time for TB was clearly shorter than that 

for the conventional Bench Grafting method, reducing labour time during the grafting process by 40%. 

During the trial by 5 inexperienced workers, the TB method achieved 100% survival rate and trees showed 

good growth. It was concluded that TB was a simple and easy citrus tree preparation technique that can 

be mastered even by non experienced operators with success rates similar to those achieved by skillful 

Bench Grafting operators. 

S11O02 

Performance of citrus nursery trees and two-year older trees after transplantation in the field 

Zekri M. 

University of Florida, USA. maz@ufl.edu 

Because citrus production must use more efficient techniques and practices for rapid recovery of capital 

investment and maximum net returns, a long-term field study was conducted to evaluate the performance 

of four groups of ‘Valencia’ orange trees on ‘Volkamer’ lemon rootstock. Before being planted in the grove, 

three groups of trees came from a container nursery, transplanted in three different size bags (30-, 45-, or 

60-cm-long and diameter) and allowed to grow for two years. The trees of the fourth group were two-year 

young standard container nursery trees grown in 10 x 10 x 35-cm plastic citripots. For each group, growth, 

leaf mineral concentration, fruit production and quality were determined and net income per acre was 

computed. The young nursery trees accumulated more potassium and less calcium in their leaves and had 

less soluble solids, acid, and juice in their fruit. During the first four years after planting, tree size and fruit 

production were the highest for the trees coming from the large size bags. It took six years for the young 

trees coming directly from the nursery to catch up the trees previously grown for two extra years in 60-cm 

bags. 

S11O03 

Effect of inarched, two-rootstock trees, on development and yield of ‘Valencia’ orange orchards 

Lima J.E.O. 1 , and Lima J.E.P. 2 

1 Mudas Cítricas Citrolima (CITROLIMA), Director, Brazil; and 2 Rucks Citrus Nursery (RCN), General Manager, USA. 

lima@citrolima.com.br 

Susceptibility to Sudden Death, Blight and Foot Rot diseases and to nematodes has not prevented ‘Rangpur’ 

lime from still being the most used citrus rootstock in Brazil due to its adaptability to poor soils and its 

drought resistance. Historically, inarching trees on ‘Rangpur’ lime with rootstocks that are resistant to 

diseases induced resistance to root and trunk diseases. Experiments were established in 2005 and 2007 to 


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compare ‘Valencia’ trees on (1) ‘Rangpur’ lime, on (2) ‘Swingle’ citrumelo, or (3) as inarched using these 

two rootstocks. Inarched trees had the same size as those on ‘Rangpur’ alone and both types were larger 

than trees on ‘Swingle’ alone in the first 5-7 years of the orchards. Inarched trees had similar yields as those 

on ‘Rangpur’ lime alone and both types yielded more than trees on ‘Swingle’ alone. In addition, inarched 

trees had fruit quality intermediary between that of fruit from trees on ‘Rangpur’ and that of fruit from 

trees on ‘Swingle’ alone. 

S11O04 

Morphological and yield characteristics of ‘Washington’ navel orange and ‘Tahiti’ lime trees 

produced with buds from floral versus vegetative mother shoots 

Lovatt C.J. 1 , and Krueger R.R. 2 

1University of California-Riverside (UCR), Department of Botany and Plant Sciences, USA; and 2USDA-ARS National Clonal Germplasm 

Repository (USDA-ARS), USA. carol.lovatt@ucr.edu 

Citrus cultivars bear “floral” shoots that produce more inflorescences than vegetative shoots (411 

inflorescences, 11 vegetative shoots). Each cultivar also bears “vegetative” shoots that produce fewer 

inflorescences (208) and more vegetative shoots (202) than floral shoots on a similar number of nodes. 

Canopy sections in which floral shoots develop contribute a greater percent of tree total yield than those 

dominated by vegetative shoots. We hypothesized that trees propagated from buds taken from floral shoots 

would retain the internal physiological status of a floral mother shoot to produce more floral daughter shoots 

than trees propagated from buds taken from vegetative mother shoots and thus be more productive. Buds 

from the two types of mother shoots collected from ‘Tahiti’ lime and ‘Washington’ navel orange were budded 

on ‘Carrizo’ citrange rootstocks. Forty trees were established in a field at UC-Riverside. At age 3 years, ‘Tahiti’ 

lime trees propagated from buds from floral mother shoots produced 28% more fruit than trees propagated 

from vegetative mother shoot buds. Similarly, 3-yr-old ‘Washington’ navel orange trees produced with buds 

from floral mother shoot yielded 26% more fruit than trees produced with buds from vegetative mother 

shoots. At the end of June drop, 4-yr-old ‘Washington’ navel orange trees propagated from floral mother 

shoot buds retained 35% more fruit than trees propagated with vegetative shoot buds, but the reverse was 

true for ‘Tahiti’ lime. 

S11O05 

Effect of different pruning severities on incidence of creasing and fruit quality in sweet orange 

Hussain Z., Singh Z., and Mandel R. 

Horticulture Research Laboratory, (HRL), Department of Environment and Agriculture, School of Science, Faculty of Science and 

Engineering, GPO Box U1987, Perth, 6845, WA, Australia. zachoundi@yahoo.com 

Creasing (albedo breakdown) is a physiological disorder with cracks in the internal white tissue (albedo) 

causing puffiness of orange peel. It causes considerable economic losses to citrus growers in Australia and 

other parts of the world. We investigated the effects of pruning severities on incidence of creasing and fruit 

quality in ‘Washington’ navel, ‘Lane Late’ and ‘Navelina’ sweet oranges. Pruning treatments including control 

(no pruning), light pruning (25% branches) and severe pruning (50% branches) were applied after fruit harvest 

on 20th September, 2010 at Gingin, Western Australia. The experiment was laid down following a split plot 

design, with four replications and single tree as an experimental unit. Thirty five ripe fruits per tree were 

harvested randomly around the tree canopy to determine the incidence of creasing and fruit quality. Results 

showed that both pruning treatments have reduced percentage of creased fruit and creasing index in all 

three cultivars as compared to control. Severe pruning was more effective in reducing creasing in all cultivars 

than light pruning. The effects of pruning on soluble solids and acid ratio, ascorbic acid, total antioxidants, 

individual sugars and organic acids in the juice will also be presented and discussed. In conclusion, severe 

pruning was more effective in reducing the incidence of creasing and enhancing the fruit quality in sweet 

oranges. 


S11O06 

Reduction of fruit splitting and the incidence of creasing of ‘Nova’ mandarin and ‘Washington’ 

navel orange by NAA sprays 

Greenberg J. 1 , Kaplan I. 1 , Tagari E. 1 , Fainzack M. 2 , Egozi Y. 2 , and Giladi B. 2 

1 Ministry of Agriculture, Extension Service, Israel; and 2 Mehadrin-Prior, Israel. yogreen@shaham.moag.gov.il 

‘Nova’ mandarin and ‘Washington’ navel orange in Israel suffer from peal splitting, causing fruit loss of up 

to 50,% and from creasing, disqualifying the fruit for fresh marketing. The effects of naphthaleneacetic acid 

(NAA 300mg/L), tank-mixed with ‘Bonus-NPK’ fertilizer (5%), on the yield, fruit number, fruit size, fruit quality, 

fruit splitting and creasing were studied. In ‘Nova’ mandarin, different application times were examined, on 

small fruitlets (15-20 mm in diameter)-when NAA causes fruit thinning, and on larger fruitlets (26-32 mm 

in diameter) when NAA does not affect fruit abscission. NAA spray on large fruitlets reduced creasing from 

37% in control to 10% in sprayed trees. Moreover, fruit drop due to splitting was also reduced by 14%. In 

‘Washington’ navel orange, NAA spray on large fruitlets (30 mm) reduced creasing by 30%, while the common 

spray with giberellic acid (20 mg/L) in August reduced creasing by 20%. In both varieties, NAA sprays on small 

fruitlets reduced fruit number and yield, while spraying larger fruitlets had no effect on fruit number or yield. 

The NAA sprays had no significant effects on the percent of juice, total soluble solids and the acid content of 

the fruit. The data suggest that NAA treatment is effective in reducing creasing and splitting when sprayed 

on large fruitlets, at the stage that it does not affect fruit size and fruitlet thinning anymore. Results and their 

implication regarding cultural practices are discussed. 

S11O07 

On-farm citrus trials in Australia: Effective extension for commercial assessment 

Falivene S. 1 , Connolly K. 1 , and Cannard M. 2 

1 NSW Department of Primary Industries (NSW DPI), Intensive Industries, Australia; and 2 Murray Valley Citrus Board (MVCB), Australia. 

steven.falivene@dpi.nsw.gov.au 

Many products and practices have been promoted to the citrus industry and little is known about their 

performance under Australian conditions. Some of these products have been trialed within Australia. 

Performance of some of these products on farm has been highly variable causing confusion in the industry. 

The variability is probably due to differences in site (e.g. soil, climate, variety) and management (e.g. irrigation, 

nutrition). This project assesses the cost benefit of a number of citrus practices promoted to industry on 

grower’s properties. The project utilizes active learning principles by facilitating grower participation with 

trials (planning, maintenance & reporting). Over 20 trials have been implemented in the past two seasons. 

Trials included ground and foliar potassium applications, pruning, foliar fruit size sprays, kaolin clay foliar 

sprays and crop regulation. Trials have resulted in cost saving with reduced potassium application. The project 

developed tools and methods to enable efficient and effective in-field collection and analysis of data. This 

enabled the project to implement more trials. Single tree replicated trials (RCBD) are the favored method to 

conduct trials. Grower feedback has been very positive indicating that it has helped them make improved 

and cost effective management decisions. On-farm trials are a very effective extension method to obtain fast 

assessment and adoption of best management practices suited to site conditions. 

S11O08 

Evolution of citrus mechanical harvesting in Florida – Lessons for the future 

Roka F.M. 

University of Florida (UF), Southwest Research and Education Center, USA. fmroka@ufl.edu 

Florida citrus growers have invested more than $40 million since 1995 to develop mechanical harvesting 

systems. Technological improvements allowed mechanically harvested acreage to increase steadily between 

1999 and 2009 and reach more than 14,000 hectares. Since 2009, however, the trend for mechanical 

harvesting has been downward and by the end of the 2010-11 season, the number of hectares mechanically 

harvested had fallen by two-thirds. Reasons behind the movement away from mechanical equipment include 


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horticultural, engineering, and economic. The spread of Huanglongbing (HLB, ex Greening) has reduced the 

overall tree health in Florida and has heightened growers’ long-standing concern over the added physiological 

stress that comes with mechanical harvesting equipment. Equipment performance, as measured by fruit 

recovery percentage, has declined as tree canopy uniformity has deteriorated from effects of various tree 

diseases, particularly from HLB. As the performance efficiencies of harvesting equipment eroded, the unit costs 

of mechanical harvesting increase. The purpose of this paper is to further explore these factors and discuss 

how the objectives of growers and juice processors need to be integrated into future designs of mechanical 

harvesting systems. Data on the ownership and operational costs of existing equipment strongly suggests 

that the potential for harvest cost savings through mechanical harvesting systems remains significantly high. 

S11P01 

Study on mushroom dregs application in citrus nursery 

Guan B., Chen K.L., He J., and Liu J.J. 

Horticulture Research Institute, Sichuan Academy of Agricultural Sciences (HRI, SAAS), Centre of Fruit Research, China. 

chen-kl@163.com 

Peat is an important substrate widely used in citrus nurseries in China. The commonly used formula is peat:sand/ 

soil:husk of rice = 4:4:2 or peat:soil = 6:4. Use of peat was restricted during recent years. Furthermore, mushroom 

producing houses produced great quantities of mushroom dregs at harvest which were often disposed of as 

garbage. The aim of this study is to investigate the feasibility of using mushroom dregs instead of peat in citrus 

nurseries with nutritional bags. ‘Ziyang-xiangcheng’ (Citrus junos), an important resistant rootstock to alkaline 

soil, and five different mushroom dregs were used in this experiment. The trial proportion of the seedling 

substrate was mushroom dregs:soil:peat = 1:2:2, 1:1:1, and 1:1:0. There were 2 controls, control 1 had mushroom 

dregs:soil:peat = 0:1:1, and control 2 was only soil. Each treatment had three replicates with 100 seedlings per 

replicate. The effects of mushroom dregs on the growth of seedlings in the nutritional bags were evaluated. 

The results showed that ‘Ziyang-xiangcheng’ seedlings can survive and grow well in most media. The seedlings 

height of 11 mushroom dreg treatments and seedlings diameter of 9 treatments were superior to control 1, 

and all mushroom dregs treatments were superior to control 2. Therefore, it is feasible and economical to apply 

certain mushroom dregs instead of peat in the substrate of citrus container seedlings. 

S11P02 

Effect of soil preparation systems, mulching and rootstocks on ‘Pera’ orange (Citrus sinensis) 

performance in the northwest of Parana State, Brazil 

Auler P.A.M. 1 , Fidalski J. 2 , Gil L.G. 2 , and Pavan M.A. 2 

1 Instituto Agronômico do Paraná (IAPAR), Área de Fitotecnia, Brazil; and 2 Instituto Agronômico do Paraná (IAPAR), Área de Solos, 

Brazil. aulerpe@iapar.br 

The objective of this work was to evaluate the effect of minimum soil preparations and mulch management 

on the performance of orange trees in a Typic Haplorthox from Caiua Sandstone soil type with lower chemical 

fertility and water storage capacity, and higher susceptibility to erosion. The experiment was established in an 

area located in the Ipiranga farm (Cocamar), at Paranavaí municipality, Parana State, Brazil. The experiment was 

laid out as a split-split plot design, with 12 treatments and 4 replications. The main plots were used to study the 

soil preparations: conventional with tillage in total area, and minimum preparation in strip and direct planting 

with partial tillage. In the subplots, the management of the tree rows, with and without mulch was adopted. In 

the split-split plots the rootstocks ‘Rangpur’ lime (Citrus limonia) and ‘Cleopatra’ mandarin (C. reshni) were used. 

The ‘Pera’ orange trees were planted in 2003 with a spacing of 6.8 m x 3.5 m. The mulch was established in the 

rows from mechanically mowing the Brachiaria brizantha weeds that grew between rows. There was no- effect 

of soil preparations on fruit production and average fruit weight of the first six year crops. Mulching increased soil 

K levels and water holding capacity and reduced the need for weed control. In the trees, mulching kept the fruit 

production under ‘Rangpur’ and reduced it under ‘Cleopatra’ rootstocks. The minimum soil preparations evaluated 

showed an important management for establishing orange orchards in this region. The ‘Rangpur’ rootstock was 

more adapted to the mulch management treatment used in this study than was ‘Cleopatra’ rootstock. 

Our thanks to the Fundação Araucária for their financial support. 


S11P03 

Evaluation of rootstocks for the ‘Tahiti’ lime in the municipality of Jaíba, Brazil 

Alves R.R., Machado D.L.M., Salomão L.C.C., Siqueira D.L., and Silva S.D.R. 

Universidade Federal de Viçosa (UFV), Departamento de Fitotecnia, Brazil. lsalomao@ufv.br 

The ‘Tahiti’ lime (Citrus latifolia) is one of the most produced fruits in the irrigated region of Jaíba perimeter, 

Minas Gerais State. The fruit is for the domestic market and export. However, ‘Rangpur’ lime (C. limonia) is 

the only rootstock used in the region. Rootstock diversification is important. The aim of this study was to 

evaluate the influence of twelve cultivars of rootstocks on the development and fruit quality of ‘Tahiti’ lime 

grown in the municipality of Jaíba (latitude: -20° 15’ 18’’ and longitude: -43° 40’ 28’’). The experimental 

design consisted of randomized blocks, with twelve treatments (rootstocks) and five replications. The trees 

were evaluated for annual productivity, diameter of rootstock, diameter of the scion, and height and diameter 

of the canopy. The fruits were evaluated for color, soluble solids content in the juice, juice titratable acidity, 

percentage of juice and levels of vitamin C. The largest productivity was induced by rootstocks ‘Volkamer’ 

lemon (C. volkameriana), ‘Cleopatra’ mandarin (C. reshni) and ‘Citrandarin 1710’ (C. reticulata x Poncirus 

trifoliata). The greatest tree height and best fruit quality were observed in trees grafted on ‘Limeira’ trifoliate 

(P. trifoliata), ‘Citradia 1708’ (C. aurantium x P. trifoliata), ‘Cleopatra’ mandarin and ‘Citrandarin 1710’. The 

latter two had better potential as alternative rootstocks to ‘Rangpur’ lime. 

S11P04 

Development and production of ‘Tahiti’ lime IAC-5 grafted on ‘Flying Dragon’ (Poncirus trifoliata 

var. monstrosa), grown in high planting densities 

Machado D.L.M., Alves R.R., Siqueira D.L., Salomão L.C.C., and Silva S.D.R. 

Universidade Federal de Viçosa (UFV), Fitotecnia, Brazil. siqueira@ufv.br 

The high citrus density planting using the rootstock ‘Flying Dragon’ (Poncirus trifoliata var. monstrosa) is possible 

because it is a rootstock that has the ability to induce dwarfing and produce small size trees, resulting in greater 

ease of orchard management and increased productivity of the plantings. Thus, the objective of this work was 

to evaluate tree growth and fruit quality of ‘Tahiti’ lime (Citrus latifolia), cultivar IAC-5, grafted on ‘Flying Dragon’ 

using spacings of 1 m, 1.5 m, 2 m, 2.5 m or 3 m between trees in the row by 6 m between tree rows. The 

experiment was conducted in the city of Jaíba (latitude 20° 15’ 18’’, longitude 43° 40’ 28’’) in a randomized block 

design with six repetitions. The trees were evaluated for annual productivity, diameter of the rootstock and 

of the scion, and height and diameter of the canopy. The fruits were evaluated for juice content, total soluble 

solids, titratable acidity and vitamin C. In the period 2010-2012, productivity per hectare in 6 m x 1.5 m spacing 

was higher than that of the other spacings. Effect of spacing was minor on fruit quality, being that the spacing 

6 m x 3 m provided greater contents in fruit juice, vitamin C and total soluble solids. No significant differences 

were found regarding tree growth characteristics between treatments. The results suggest the possibility that 

increased planting density will be used in future citrus plantings using ‘Flying Dragon’ rootstock. 

S11P05 

Effect of shade screen on production, fruit quality and growth parameters in ‘Fino 49’ lemon 

trees grafted on Citrus macrophylla and sour orange 

Gimeno V. 1 , Simón I. 2 , Martínez V. 1 , Lidón V. 2 , Shahid M.A. 3 , and García-Sánchez F. 1 

1 Centro de Edafología y Biología Aplicada del Segura (CEBAS), Plant nutrition, Spain; 2 Escuela Politécnica Superior de Orihuela (EPSO), 

Spain; and 3 University of Sargodha, Pakistan. vicente@cebas.csic.es 

Spain ranks as the second-largest lemon fruit producing country in the world and it is one of the largest 

exporters. About 80% of the production is located in the arid southeast (Murcia and Alicante). In citrus, it is 

known that 50% shade screens reduce leaf temperature and light intensity at midday in summer and spring 

periods in these areas, resulting in an increase in the photosynthetic leaf water use efficiency (WUEphy = 

ACO2/Eleaf). In this experiment the effect of shading with Aluminet-50 screen (which reduces about 50% of 

incident photosynthetically active radiation) on the production, fruit quality, leaf water relations, leaf mineral 


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composition, and growth parameters of ‘Fino 49’ lemon trees grafted on two rootstocks, Citrus macrophylla 

and sour orange, were studied. This study was carried out in Santomera (Murcia) over a four-year period (2008- 

2011) using seven-year old trees at the beginning of the experiment. Shade screen had similar effect in trees 

grafted on both rootstocks. Shading increased the height and canopy perimeter producing trees with a greater 

canopy volume than that under full sunlight (increase of about 60% compared with full sunlight trees). Despite 

that, shading reduced fruit production. Trees under full sunlight produced in total 81 and 45 kg/tree, while 

trees under shade produced 70 and 33 kg/tree, respectively for C. macrophylla and sour orange. Leaf water 

status according to leaf water potential (Ѱw) and relative water content (RWC) was greater in trees under 

shade screen. Shading affected the physical characteristics of the fruit from trees on C. macrophylla as fruits 

under shade had less fresh weight and smaller width than fruits from trees under full sunlight. Leaf mineral 

concentration was not affected by shading, except for B and Mn where the concentration increased by shading. 

S11P06 

Effect of liquid fertilizer applied by injection into the soil on quality of ‘Tarocco’ blood orange 

He J., Chen K.L., Guan B., and Liu J.J. 

Horticulture Research Institute, Sichuan Academy of Agricultural Sciences (HRI, SAAS), Centre of Fruit Research, China. 

chen-kl@163.com 

Experiments using four different treatments of liquid fertilizer (No. 1 to No. 4) and one treatment of compound 

fertilizer (N:P 2 O 5 :K 2 O = 15:15:15) (No. 5) were conducted continuously for 3 years to compare the fertilization 

effect on fruit quality of ‘Tarocco’ orange. The liquid fertilizer (containing humic acid and dissolved N, P, K) 

was injected into the soil by pressure increasing device to a depth of 20 cm-30 cm. The results indicated that 

the fruit of all liquid fertilizer treatments had higher content of total soluble solids (TSS) and total sugars 

than those of compound fertilizer. The content of TSS increased by 13.5%, 14.4%, 7.2% and 2.7% and total 

sugars increased by 25.9%, 24.7%, 11.5% and 6.7%, respectively for treatments No. 1, 2, 3 and 4, compared 

to those of fruit from treatment No. 5. The content of total acid for liquid fertilizer was different. Treatment 

No. 1 and No. 2 produced lower total acid content in fruit than did treatment No. 5 while treatments No. 

3 and No. 4 produced higher total acid content. The fruits of treatments No. 1, 2, 3 and 4 also had higher 

vitamin C content than fruit from No. 5 treatment. In short, the fruit quality of ‘Tarocco’ blood orange could 

be improved by liquid fertilizer injection into soil. 

S11P07 

Effect of branch girdling and ringing on carbohydrates, chlorophyll fluorescence and SPAD index 

in leaves of ‘Tahiti’ acid lime 

Santos D. 1 , Siqueira D.L. 1 , Salomão L.C.C. 1 , and Cecon P.R. 2 

1 Universidade Federal de Viçosa (UFV), Fitotecnia, Brazil; and 2 Universidade Federal de Viçosa (UFV), Estatística, Brazil. 

lsalomao@ufv.br 

This work evaluated the effects of girdling and ringing on the dynamics of carbohydrates, chlorophyll 

fluorescence and SPAD index in leaves of ‘Tahiti’ acid lime. Three year-old trees cultivated in the subtropical 

climate of Minas Gerais, Brazil, were used in the experiments. These practices were applied at 8 dates: June 

30th 2009, July 15th 2009, July 30th 2009 and August 14th 2009 and June 15th 2010, July 5th 2010, July 

25th 2010 and August 14th 2010 plus a control (not girdled nor ringed). Girdling and ringing were both 

performed on the main branches of the trees, 10 cm above their insertion on the trunk. Greater contents of 

starch were observed until 50 to 60 days after girdling on both 2009 and 2010 crops, returning to normality 

around day 120 due to the reestablishment of phloem transport. Unlike girdling, the responses obtained 

with ringing were mostly similar to those observed in control trees. Girdling reduced the ratio of variable to 

maximal chlorophyll fluorescence (Fv/Fm relationship) in the 2009 and 2010 years. In 2009, trees subjected 

to ringing presented maximum values of Fv/Fm similar to the ones of control trees on day 90 after incision. 

In 2010, plants subjected to ringing did not present variation in Fv/Fm relationship over time, similar to the 

control plants. Regarding SPAD index, results presented similar trends in both years. In the 2009 treatments, 

all girdled trees presented a reduction in the index, reaching minimal values around days 80 to 90 after 

incision. In 2010 treatments, those values were reached around days 100 to 110. 


S11P08 

Production of ‘Tahiti’ acid lime after branch girdling or ringing 

Santos D., Siqueira D.L., Salomao L.C.C., and Cecon P.R. 

Universidade Federal de Viçosa (UFV), Fitotecnia, Brazil. siqueira@ufv.br 

This work evaluated the effects of girdling and ringing on ‘Tahiti’ acid lime flowering, rate of flower drop and 

fruit set. Trees of three years of age were used. They were grown in the subtropical region of the state of 

Minas Gerais, Brazil. These cultural practices were applied at 8 dates: June 30 th 2009, July 15 th 2009, July 30 th 

2009 and August 14 th 2009 and June 15 th 2010, July 5 th 2010, and August 14 th 2010 plus a control (not girdled 

nor ringed). Girdling and ringing were both performed on the main branches of the trees, 10 cm above their 

insertion on the trunk. Regardless of the year and time of application, girdling and ringing did not alter rate 

of flower drop and time of flowering and fruit harvest. Fruit set (PFS), number of fruit produced (NFP) and 

fruit production (PPP) of girdled trees were greater than those for control trees, whereas average mass (AMF) 

and average diameter of fruits (ADF) were smaller. Ringed plants did not present differences in relation to the 

control trees. Regardless of the time when the treatments were applied, in 2009 PFS was 3.19 times greater 

in girdled plants in comparison to the other treatments. Girdling also caused a reduction of 43% in flower 

abscission. This reduction was responsible for an increase of 117% in PFS, 117% in NFP and 84% in PPP in 

relation to ringed trees. However, as fruit set increased in girdled trees, AMF was reduced by 12% compared 

to fruit from ringed or control trees. 

S11P09 

Horticultural package for high quality ‘Tahiti’ lime production 

Mourão Filho F.A.A. 1 , Stuchi E.S. 2 , Cantuarias-Avilés T. 1 , Espinoza-Núñez E. 1 , Bremer Neto H. 1 , Bassan M.M. 1 , and Silva 

S.R. 1 

1Universidade de São Paulo (USP), Departamento de Produção Vegetal, Brazil; and 2Embrapa Mandioca e Fruticultura (EMBRAPA), 

Diretoria Científica, Brazil. francisco.mourao@usp.br 

The production and international marketing of the ‘Tahiti’ lime (Citrus latifolia) have significantly expanded 

in recent years. On the other hand, increasing production costs and the occurrence of novel destructive 

diseases have motivated the development of more competitive and efficient systems for high quality fruit 

production. During the past years, four experiments were conducted in Southern Brazil to optimize fruit yield 

and quality of ‘Tahiti’ lime. This work summarizes the most important achievements from these experiments 

in order to propose a horticultural package for high quality ‘Tahiti’ lime production. The main results from 

these experiments indicate that dwarfing rootstocks may lead to early-bearing, higher yield efficiency and 

higher fruit quality of ‘Tahiti’ lime. Although some other rootstocks may induce high drought tolerance 

and higher cumulative yield, in this horticultural package the use of irrigation was essential for even higher 

efficiency. On the other hand, plant size, fruit yield and quality were directly and significantly affected by the 

‘Tahiti’ lime scion selection. Fruit quality and conservation were also significantly influenced by the harvest 

method. The combination of these practices, including the correct choice of the scion selection/rootstock 

combination, the use of irrigation and the adequate harvest methods may lead to increased production of 

high quality ‘Tahiti’ limes. 

S11P10 

Field evaluation of two canopy shake systems, OXBO 3210 and OXBO 3220, on citrus orchards in 

Andalusia (Spain) 

Arenas Arenas F.J., Salguero A., and Hervalejo A. 

Instituto de Investigación y Formación Agraria y Pesquera (IFAPA). Centro Las Torres-Tomejil, Consejería de Agricultura, Pesca y Medio 

Ambiente. Junta de Andalucía, Spain. fjose.arenas@juntadeandalucia.es 

Spanish citrus orchards are threatened by the globalization of the market and the existence of countries with 

cheaper labor, especially those orchards destined to juice industry in which manual harvest represents about 

50% of the final production costs. In this situation mechanical harvesting is a promising way to decrease harvest 


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cost and thereby increase the profit margin in production of citrus fruit for processing. However, adoption of 

mechanical harvesting requires a major effort in the selection and adaptation of existing equipment, as well as 

in the design of the plantations. In 2009, several field experiments using two continuous canopy shake systems, 

OXBO 3210 and OXBO 3220, were conducted in unadapted citrus orchards to evaluate the effect of harvester 

amplitude (CPMs) and harvester speed on fruit removal efficiency, tree damage and fruit quality. The results 

suggest that a suitable adaptation of citrus plantations (continuous hedgerows with high canopy and bottom 

canopy pruned to a height of 1 m above the ground) together with an appropriate calibration of the equipment, 

would allow to obtain high fruit removal efficiency without causing considerable damage to the tree or affect 

the physical integrity of the fruits for processing. Mechanical harvesting had no effect on internal fruit quality. 

S11P11 

Production seasonality of ‘Tahiti’ lime in three consecutive harvests under semiarid climatic 

conditions 

Maia V.M., Álvarez J.M., Oliveira F.S., Gomes F.H.C., Azpiazú I., and Salles B.P.A. 

Universidade Estadual de Montes Claros (UNIMONTES), Ciências Agrárias, Brasil. victor.maia@unimontes.br 

Cultivation of ‘Tahiti’ lime is increasing significantly in the Minas Gerais State, due to its good adaptation 

to the semiarid climate of the region. This work aimed to evaluate the seasonality of irrigated ‘Tahiti’ lime 

production using three consecutive harvests under semiarid conditions. The experiment was conducted in a 

commercial orchard, located in Northern Minas Gerais (altitude of 449 m, latitude 15°05’34”S, and longitude 

43°58’44”W). The orchard was planted in January 2007 and the trees started producing in December 2008. 

The evaluations were made when fruits were harvested, starting the beginning of December 2008 until 

December 2011. All the fruits from all the trees were collected weekly, obtaining the total yield for each month 

throughout the year. These fruits were harvested when they reached a diameter of 54 mm. Determinations 

were made of total production, yield, and fruit was sorted for export, domestic market and discards. Total 

yield was calculated by adding the weight of the fruits intended for the export, that for the domestic markets 

and that for the discards for each month. Production of ‘Tahiti’ lime occurs in all months of the year under 

semiarid climatic conditions. The yield obtained in the first, second and third year of production was 11,611, 

8,809 and 12,102 Kg∙ha -1 , respectively. There are peaks of production in May, June and November. 

Support: FAPEMIG. 

S11P12 

Enhancement of citrus value chain production in Pakistan and Australia under the AusAid Program 

Khurshid T. 1 , Ahmad I. 2 , Jaskani M.J. 3 , Nabi G. 4 , Tahir T. 5 , Ali W. 5 , Rahman A. 6 , Khan M.A. 7 , and Rahman H. 5 

1 Dareton Primary Industries Institute (DPII), New South Wales. Department of Primary Industries, Australia; 2 FAO Representation NARC 

Premises Park Road Islamabad (FAO), Program Development, Islamabad; 3 University of Agriculture Faisalabad (UAF), Horticulture, 

Pakistan; 4 Agriculture Research Institute, Tarnab (ARI), Horticulture, Pakistan; 5 National Agricultural Research Centre (NARC), 

Horticulture, Pakistan; 6 Citrus Research Institute, Sargodha (CRI), Citrus Physiology, Pakistan; 7 Fruit and Vegetable Development 

Project (FVDP), Horticulture, Pakistan. tahir.khurshid@dpi.nsw.gov.au 

Citrus is a major fruit crop in Pakistan, and ‘Kinnow’ mandarin is the dominant cultivar. Currently 53% of 

citrus fruit produced in Pakistan is consumed domestically, and ca. 10% is exported. A small proportion is 

processed, and postharvest losses are high. Export of ‘Kinnow’ mandarin from Pakistan is trending upwards, 

but the industry’s capacity to supply export markets is limited. A constraints analysis conducted under the 

auspices of the Agricultural Sector Linkages Program during 2006 suggested that the development of the 

Pakistan citrus industry was constrained by poor nursery practices, dependence on a limited range of varieties, 

poor irrigation and crop management practices. A project led by NSW DPI and collaborative organizations 

in Pakistan including, the Pakistan Agriculture Research Council, Islamabad, the Citrus Research Institute, 

Sargodha, the University of Agriculture, Faisalabad, the Agriculture Research Institute, Tarnab, Peshawar and 

Fruit and Vegetable Development Project, Lahore has been funded by AusAid to increase citrus production 

in Pakistan through transfer of improved orchard management techniques. The overall aim of this project is 

to improve mandarin and orange productivity in Pakistan through germplasm transfer to extend the growing 


season and test a range of varieties in the hotter climate of Pakistan, and provide training in the areas of 

nursery production, irrigation and orchard management. Technology transfer is taking place via small to 

medium scale demonstration sites in citrus producing regions in Pakistan, and via more formal training of 

citrus research and extension personnel in Pakistan and Australia. 

S11P13 

Technology and production costs for organic versus conventional ‘Navelina’ citrus orchards 

Reis D. 1 , Marreiros A. 2 , Fernandes M.M. 2 , Mourão I. 3 , and Duarte A. 4 

1 Instituto Politécnico de Viana do Castelo (IPVC), Escola Superior Agrária de Ponte de Lima, Portugal; 2 Direcção Regional de Agricultura 

e Pescas do Algarve (DRAPALG), Portugal; 3 Centro de Investigação de Montanha/Instituto Politécnico de Viana do Castelo (CIMO/ 

IPVC), Escola Superior Agrária de Ponte de Lima, Portugal; and 4 Institute of Mediterranean Agricultural and Environmental Sciences - 

University of Algarve (ICAAM/UAlg), Faculty of Sciences and Technology, Portugal. dhcreis@gmail.com 

The organic production is often associated with higher production costs when compared to conventional 

farming but other authors have reported a decrease in production costs for organic farming. In this study 

we describe the operations carried out over a year in an organic orchard of ‘Navelina’ orange located in the 

southern Portuguese region of Algarve. In addition, we describe the operations performed in two conventional 

orchards, located near the organic orchard. The corresponding production costs were determined. The organic 

orchard was managed quite differently from conventional orchards. The differences were significant in relation 

to weed control, fertilization and pest and disease control. Although some biological orchard operations are 

very expensive, the total production costs are similar in organic and conventional orchards. Yield was also 

similar in both cultivation systems. The data obtained allowed for an evaluation of the economic benefits of 

organic farming in this cultivar. 

S11P14 

Prediction of moving northward of favorable regions to cultivate subtropical citrus by estimation 

of changes in annual mean and minimum air temperature in Japan 

Sugiura T., Sakamoto D., Sugiura H., Koshita Y., and Asakura T. 

National Agriculture and Food Research Organization (NARO), Institute of Fruit Tree Science, Japan. sugi@affrc.go.jp 

Satsuma mandarin (Citrus unshiu) is the leading citrus variety in Japan. It often suffers high-temperature 

damage such as sunscald, coloring disorder and puffy fruit. It has been predicted that satsuma mandarin 

production in Japan will become difficult under increasing temperatures resulting from global warming. 

Because fruit trees need several years to grow until they reach the productive age and once they start 

producing, they are kept for many years, it is important to make planting plans for the long term and 

incorporating climate change in the decision making. This study is an examination of whether ‘Tankan’ (Citrus 

tankan), which in the past was the major subtropical citrus in Japan, can be grown in the areas where satsuma 

mandarin is grown. To develop maps showing the most favorable regions to cultivate ‘Tankan’ in the future, 

the annual mean air temperature and the lowest air temperature in one year were estimated by using mesh 

temperature data (approximately 1 by 1 km resolution) that was derived from SRES-A1B emission scenario 

and a general circulation model, MIROC3-HiRes. Results indicate that ‘Tankan’ can be basically cultivated in 

the region where the satsuma mandarin cultivation became difficult. Subtropical citrus production may be 

selected as one of the adaptation plans after 40 years in many of the present citrus zones with the exception 

of inland area where cold damage will often occur. 

S11P15 

INTA´s Citrus Improvement Program 

Costa N., Plata M.I., and Anderson C. 

Estación Experimental Agropecuaria Concordia (INTA), Argentina. anderson.citrus@gmail.com 

INTA´s Citrus Improvement Program was established 28 years ago as an industry insurance policy. Since 

1984, the Concordia Experiment Station maintains the citrus mother trees genetically and sanitarily 


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checked. The objective is to secure propagating material of commercial varieties for industry needs. Varieties 

are selected from research projects and/or introductions and are subject to quarantine controls and a 

sanitation process. The selected trees are shoot-tip grafted and indexed for Tristeza, Psorosis, Exocortis, 

Cachexia, Citrus Variegated Chlorosis, Canker and Huanglongbing. Two hundred and thirteen scion and 

rootstock varieties are maintained and evaluated annually for their agronomic characteristics and sanitary 

status by visual observation and biological, immunochemistry and/or molecular diagnostics. Data obtained 

on origin, botanical characteristics, agronomic performance, sanitary status and availability of propagation 

material is recorded. The information is available at INTA’s website (www.inta.gov.ar/concordia). Basic 

material is exported to citrus producing countries and sent to germplasm banks on request. The isolation, 

annual evaluations, pest monitoring and disease diagnosis guarantee the quality of the material offered by 

the Program to Argentine citrus industry. 

S11P16 

Labor-saving practices for ‘Shatangju’ mandarins in China 

Ma P.Q., and Wu W. 

Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization, Ministry of Agriculture, Fruit Research Institute, 

Guangdong Academy of Agricultural Sciences, China. mapeiqia@163.com 

‘Shatangju’ mandarin (Citrus reticulata) is one of most important citrus variety in Guangdong, China. Some 

current practices, like excessive fine pruning of the tree, and manual summer shoot tip removal to avoid fruit 

drop, are expensive and inefficient. Experiments have been carried out using simpler branch pruning methods, 

restraining summer shoot growth using chemicals or avoiding tip removal. The impact of such new practices 

on production costs and fruit quality has been investigated. Results showed that there were lower costs 

and better yields with the new method of branch pruning, due to 32% reduction of labor costs (4230 yuan/ 

ha versus 6225 yuan/ha with traditional pruning) and 17% increase of fruit set. Moreover fruit appearance 

and quality were improved. Furthermore, chemical summer shoot restriction significantly increased fruit 

retention (from 61.2% to 84.6%). Fruit set was also increased. However, the chemical induced blemishes on 

some fruit and apparently produced phytotoxicity. On the other hand, keeping summer shoot growth greatly 

reduced cultivation costs, but decreased production by 57.1%. 

S11P17 

FruTIC: An information and communication tool for an integrated health management of citrus 

groves 

Garrán S.M. 1 , Stablum A. 2 , Franco S. 2 , Ibarrola S. 2 , Mika R. 1 , Milera S. 2 , and Marnetto S. 2 

1 Instituto Nacional de Tecnología Agropecuaria (INTA), Province of Entre Ríos, Argentina; and 2 Asociación Cultural para el Desarrollo 

Integral (ACDI), Province of Santa Fe, Argentina. smgarran@correo.inta.gov.ar 

In order to allow the implementation of integrated management practices (IPM), an information and 

communication platform has been developed for the citrus growing area of the Uruguay River, in Argentina. 

With this objective in mind, an environmental and phenological monitoring network has been established 

throughout the whole region. This system, named FruTIC and based on the new ICTs, is accessible via 

internet through its website (http://www.frutic.org.ar) as well as through automated alerts and warnings 

implemented via SMS and e-mails. Information is hourly updated all year around, providing historical and 

current data and also forecasts and models on the evolution of most of the environmental and phenological 

variables required for fulfilling IPM practices. The system allows the access to both referential as well as 

grove personalized information on these variables. It also facilitates the technical administration of citrus 

groves since it allows that all recommendations and practices performed on every commercial plot be 

registered on line, as well as providing automated reports of all management and monitoring practices 

performed. This documentation is also needed for traceability requirements and the certification of the 

production process. FruTIC is an innovative system for the management of the citrus crop, providing 

elements for a precision, more sustainable and less contaminated citrus industry. It is also able to be 

applied on any other citrus growing areas and crops. 


S11P18 

A phytosanitary evaluation method (MEF) for commercial citrus groves. 

Garrán S.M. 1 , Mika R. 1 , Boca R.T. 2 , Beribe M.J. 3 , and Pérez A. 4 

1 Instituto Nacional de Tecnología Agropecuaria (INTA), Entre Ríos, Argentina; 2 Instituto Nacional de Tecnología Agropecuaria (INTA), 

Instituto de Clima y Agua (CNIA), Argentina; 3 Instituto de Producción Animal (CNIA), Buenos Aires, Argentina; and 4 Facultad de 

Agronomía de la Universidad Nacional de Buenos Aires (FAUBA), Argentina. smgarran@correo.inta.gov.ar 

Precision agriculture means site specific management. In order to fulfill this concept, information is needed on 

main factors affecting yield and fruit quality within the orchard. A phytosanitary evaluation method (MEF) has 

been recently developed in order to fulfill the identification of main biotic and abiotic factors affecting yield 

and fruit quality within a citrus grove and also estimating physical and economic losses attributed to each one 

of these factors as well as their spatial distributions. An improved version of this method will be presented 

which is based on field sampling of citrus commercial plots performed close to harvest time. Diagnosis and 

quantification of yield and fruit quality losses are now obtained simultaneously through the same field 

inspections performed by trained personnel and based on a systematic georeferenced tree sampling together 

with a multistage random sampling of their fruits. Fruit number of each sampled tree is estimated as well 

as main factors causing yield constraints are visually identified and categorized according to their relative 

magnitude. Fruit quality data are also obtained by categorizing every sampled fruit on trees according to 

Commercial Grading Standards, identifying and listing main factors affecting fruit grade and measuring fruit 

equatorial diameter. Data obtained from both yield and fruit quality samplings together with updated market 

prices for the different Commercial grades are then processed through algorithms and geostatistics. Since the 

method also provides information about the spatial distribution of different pests and diseases within the 

plot, it can be considered suitable to be used as a basic tool in precision fruit production. 

S11P19 

Micro budding of commercial citrus cultivars of India 


National Research Centre for Citrus (NRCC), Tissue culture, India. narukullav@gmail.com 

Commercial propagation of citrus in India and in many other countries is based on the traditional shield/T 

budding technique. The major factors that influence the performance of this technique are related to the use 

of appropriate rootstocks (1 year old ‘Rough’ lemon, 1 ½ to 2 year old ‘Rangpur’ lime) and adequate scion 

wood (round twigs having white streaks which are season restricted), and the occurrence of favorable climate 

conditions. The method takes long time (around 22 months) to produce marketable bud grafts. “Micro budding” 

is a faster propagation technique (approximately one year long) that can reduce nursery phases and reduce 

grower expenses by saving time and space. It has been developed for the first time in India at NRCC, using Citrus 

reticulata Cv. ‘Nagpur’ mandarin on 5 month old commercial citrus rootstocks of Central India. The technique 

can be easily extended to other citrus species (i.e. sweet orange, acid lime, ‘Kinnow’ mandarin). It reduces 

enormously labour and maintenance costs during the commercial propagation and can be performed in low 

cost green houses. It can also be used for fast biological screening of virus, viroids and bacteria, and in any 

many disease inoculation and expression studies. Thanks to the use of micro budding, NRCC has multiplied and 

released around 15,000 high quality plants of ‘Nagpur’ mandarin to citrus growers of Central India, within a time 

span of 11 - 12 months. Prior to commercial release, these micro budded plants have been evaluated at NRCC in 

replicated field trials. This paper reports the complete process and how field tests were performed. 

S11P20 

Evaluation of organic growing media and bio-control agents in the production of certified citrus rootstocks 

Yaseen T. 1 , Dongiovanni C. 2 , Roccuzzo G. 3 , Ippolito A. 4 , and DÓnghia A.M. 1 

1 Centre International de Hautes Etudes Agronomiques Méditerranéennes (CIHEAM/IAM.B), Italy; 2 Centro di Ricerca e Sperimentazione in 

Agricoltura, Basile Caramia, (CRSA), Italy; 3 Centro di Ricerca per l’Agrumicoltura e le Colture Mediterranee (CRA-ACM), Catania, Italy; and 

4 Dipartimento di Biologia e Chimica Agro-forestale ed Ambientale, Università degli Studi di Bari Aldo Moro, Italy. donghia@iamb.it 

Citrus groves for organic production shall fulfill the European Regulation on organic production and labeling 

of organic products (EC No 889/2008), which requires the use of citrus seedlings grown under organic 


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management. Due to the lack of nurseries able to comply with these requirements, a study was financed by 

the Italian Ministry of Agriculture (MiPAAF) regarding the preparation of suitable organic media for growing 

citrus rootstocks and for the evaluation of the commercial bio-product Clonotri (Trichoderma harzianum and 

Clonostachys rosea), and this to enhance plant vigour and protect the trees against soil-borne pathogens. 

Substrates were prepared and evaluated using the growing medium of IAM-Bari (IAMB mix) as control, 

since this substrate has been used with success for the production of citrus plants. Considering that peat 

moss is a non-renewable natural resource, commercial and experimental composts for organic production 

(ECOS and Compas, respectively) and coconut fiber were individually evaluated for reducing the peat moss 

quantity (35%) in IAMB mix. Moreover, a Guano-based fertilizer was added to the 3 growing media and 

the elemental sulfur used for pH adjustment. Trials were carried out in an insect proof screenhouse for the 

premultiplication of the trees in the Apulian certification programme. About 3-4 month-old ‘Volkameriana’ 

lemon, ‘Troyer’ citrange and sour orange seedlings were transplanted to the 3 growing media and the IAMB 

mix. All growing media were evaluated individually and in combination with Clonotri, using 20 replicates 

per treatment per rootstock. Plant growth, trunk diameter and dry weight were evaluated at the end of the 

experiment. Significant increase in vegetative parameters was obtained in all citrus rootstocks grown in the 

Compas-based growing medium. However, no significant results in enhancing plant growth were achieved by 

the combination of Clonotri. 

S11P21 

The diversification of agriculture in the new Cuban Citriculture 

Cueto J.C. 1 , Piñero J.P. 2 , Ortega I.O. 3 , and Torres L.T. 1 

1 Grupo EmpresTimes Fruticola (GEF), Direccion Técnica y de Desarrollo, Cuba; 2 Empresa Cítricos Ceiba, Dirección, Cuba; and 3 UBPC 24 

de Febrero, Cooperativa de Producción, Cuba. despacho@iift.cu 

The Cuban citrus production is developed by the specialized enterprises of Fruit Culture Enterprise 

Group (GEF) mainly; those enterprises are located all over the country under a great diversity of climatic 

conditions. The existing climatic and soil diversity also permitted the successful development of many 

other horticultural crops, like other fruits and crops with short production cycle. After the invasion of 

HLB disease to Cuba, the yields of the old and affected citrus groves have been decreasing quickly and 

the financial capabilities of the producers went down. The productive infrastructure and the industrial 

capabilities for the citrus fruit processing are not exploited efficiently during the whole year. Cuba has the 

goal to recover its citriculture through the diversification of the plantations, with plantings mainly in new 

areas dedicated to citrus production. However, in the Cuban conditions, these decisions and practices 

have very little background information available. In this paper we summarize the principal experiences 

obtained in some Cuban enterprises in the last three years (2009-11) about use of intercropping with 

minor crops in citrus plantations. This approach is analyzed in details using the results obtained by one 

citrus production cooperative at “Ceiba Enterprise”. 

S11P22 

Presence of weed biotypes with suspected resistance to glyphosate in agroecosystem citrus 

orchards in Cuba: a latent threat 

Otero L. 1 , and de Pardo R. 2 

1Institute of Research in Tropical Fruitculture, Cuba; and 2University of Córdoba, Department of Agricultural Chemistry, Spain. 

lilianotero@iift.cu 

In all the citrus orchards in Cuba, in the last few years, there has been evidence of weeds escaping from 

glyphosate control at doses which normally controlled them (1440 g∙ha -1 ) in the four annual frequencies of 

application dictated by the technologies set up for this crop. Species like Melochia pyramidata, Dichanthium 

annulatum, Momordicha charantia, and Chamaesyce prostrata show an evasive behavior towards this 

herbicide, which has had an exponential trend in its preference and use by agricultural enterprises for over 10 

years. Some weeds like Bidens pilosa and Lepidium virginicum have been problematic in enterprises in various 

areas of the country (Ceiba in La Habana and Arimao in Cienfuegos) where they occur with an occupation of 


over 50% of the infested fields. The frequent presence of Echinochloa colona and Eleusine indica is of interest 

if we take into account that they have been reported as being resistant to glyphosate in several countries like 

Argentina, Australia and the USA. This work describes the most suspicious species in the different regions of 

the country with the aim of warning about a situation, which in the immediate future could complicate the 

management of citrus orchards. 


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Session 12 

CITRUS HLB AND OTHER 

BACTERIAL DISEASES 

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S12O01 

New insights into the citrus Huanglongbing complex and potential solutions to this devastating 

disease 

Duan Y.P., Zhou L.J., Zhang M.Q., Vahling-Armstrong C., Hao G.X., Zou H.S., and Hoffman M. 

USDA-ARS-USHRL, USA. Yongping.Duan @ ars.usda.gov 

Citrus Huanglongbing (HLB) is a century-old and emerging disease that impedes citrus production worldwide. 

Candidatus Liberibacter asiaticus (Las) is the globally prevalent species of HLB bacteria. Here we describe 

molecular characterizations of Las, and our newly-developed control methods. From a genomic standpoint, 

we revealed that Las has a significantly reduced genome and unique features adapted to its intracellular 

lifestyle. For such a small genome, a large fraction, about 1/15, originates from prophages/phages. There are 

at least two prophages in the Florida isolates. Frequent recombination and reassortment of these prophages/ 

phages may contribute to the evolving diversity and plasticity of the bacteria. There are at least 8 different 

types of Las populations that exist in different hosts, different geographical origins, and in a single infection. 

Furthermore, the different Las populations may be responsible for the titer variations, such as the extremely 

low-titer seen with seed-transmitted Las bacteria from citrus and of infected Murraya paniculata. Using 

functional genomics, we have revealed several aspects of Las biology that may contribute to its pathogenicity 

including a high affinity zinc uptake system (ZnuABC), which allows Las to compete with its host for the limited 

zinc supply and an ATP translocase that facilitates parasitization of the host’s energy supply. In addition, 

Las encodes two novel autotransporter proteins that target mitochondria and may modulate host energy 

biosyntheses. Although no flagellum has yet been observed, Las encodes a functional flagellin that triggers the 

citrus basal defense response. In spite of the difficulty with HLB control, our newly-developed thermotherapy 

and chemotherapy methods eliminated or suppressed Las bacteria in the- infected plants, providing potential 

solutions for this devastating disease. 

S12O02 

Tissue-print and squash real-time PCR for direct detection of Candidatus Liberibacter spp. in 

citrus plants and insect vectors 

Bertolini E. 1 , Lopes S. 2 , Felipe R.T.A. 3 , Teresani G. 1 , Mourão F.A.A. 3 , Colomer M. 4 , Bové J.M. 5 , López M.M. 1 , and 

Cambra M. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Protección Vegetal y Biotecnología, Moncada, Valencia, Spain; 2 Fundo de 

Defesa da Citricultura (FUNDECITRUS), Plant Pathology, Araraquara, São Paulo, Brazil; 3 Universidade de São Paulo (USP), Produção 

Vegetal, Piracicaba, São Paulo, Brazil; 4 Plant Print Diagnostics S.L. (PPD), Technical Department, Guadassuar, Valencia, Spain; and 

5 Institut Nationale de la Recherche Agronomique (INRA) and Université Victor Ségalen, Bordeaux, France. mcambra@ivia.es 

Huanglongbing (HLB), the most severe disease of citrus, is seriously threatening the industry worldwide. The 

accurate detection of the Candidatus Liberibacter species associated with HLB, is essential for control and 

management of the disease. Real-time PCR is a very appropriate technique for sensitive and specific detection, 

but the need for nucleic acids purification, greatly limits the number of samples that can be processed and 

highly increases the time as well as the cost of the analyses. Direct real-time PCR detection of Ca. Liberibacter, 

overcoming nucleic acids purification, is successfully achieved by systems of sample preparation such as 

tissue-print, spot or squash methods on membranes. New, universal Ca. Liberibacter primers were designed, 

patented and used with TaqMan probe for accurate detection of plant and psyllid-vector targets immobilized 

on nylon or paper membranes. A complete kit based on this technology was successfully validated in an 

international ring-test and diagnostic parameters were estimated. HLB targets were amplified from 35% of 

1,359 squashed Diaphorina citri individuals having fed on HLB infected plants in Brazil. All samples (1,013) 

collected from citrus trees during extensive surveys in Canary Islands, Spain, where Trioza erytreae is widely 

present, tested negative; the bacterium was not detected in citrus or in psyllid species. The developed method 

demonstrated high efficiency in detecting the HLB bacterial agents in routine analyses of the many samples 

required for prevention and efficient management of the disease. 


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S12O03 

A new insect vector of Candidatus Liberibacter asiaticus, Cacopsylla (Psylla) citrisuga (Hemiptera: 

Psyllidae) 

Cen Y. 1 , Gao J. 2 , Deng X. 3 , Xia Y. 4 , Chen J. 5 , Zhang L. 1 , Guo J. 2 , Gao W. 1 , Zhou W. 3 , and Wang Z. 2 

1 Lab. of Insect Ecology, South China Agricultural University, China; 2 Institute of Tropical and Subtropical Cash Crops, Yunnan Academy 

of Agricultural Science, China; 3 Citrus Huanglongbing Research Laboratory, South China Agricultural University, China; 4 Center for 

Integrated Pest Management, North Carolina State University, USA; and 5 Crop Diseases, Pests and Genetics Research, San Joaquin 

Valley Agricultural Sciences Center, United States Department of Agriculture, USA. cenyj@scau.edu.cn 

Nymphs and adults of the pomelo psyllid (Cacopsylla (Psylla) citrisuga Yang & Li) were collected from Huanglongbing 

(HLB) symptomatic and Candidatus Liberibacter asiaticus (Las)-positive lemon trees (Citrus limon (L.) Burm.F.) 

in Yunnan Province, China. DNA was extracted from groups of psyllid nymphs, individual late-stage nymphs and 

groups of adults, and the samples were analyzed with nested-PCR (primers:1500R/27F, OI1/OI2c). The results 

showed that 10 out of 24 group-nymphs samples, 12 out of 29 individual-late-stage nymph samples, 2 out of 3 

group-adult samples were Las-positive. DNA was also extracted from group-nymph of the 1st, 2nd, 3rd, 4th and 

5th instar, then subjected to nested-PCR detections. One out of 4 1st instar, 2 out of 4 2nd instar, 1 out of 3 3rd 

instar, 1 out of 2 4th instar, and all 3 5th instar nymph samples were Las-positive. The amplified DNA fragment 

was sequenced and was 99% similar to the 16S rRNA gene of Las strain psy62 in GenBank. Transmission study 

showed that 12 out of 60 healthy lemon young plants were Las-positive after being fed by psyllid nymphs and 

adults collected from infected trees for about 1 month. These results demonstrate that in addition to Asian 

citrus psyllid (Diaphorina citri Kuwayama), C. (P.) citrisuga is another insect vector of Las. 

S12O04 

On the identity of orange jasmine and its relevance to Huanglongbing and Diaphorina citri. 

Holford P. 1 , Nguyen C.H. 1 , Beattie G.A.C. 1 , Haigh A.M. 1 , Hasick N.J. 1 , Mabberley D.J. 2 , and Weston P.H. 2 

1 Univeristy of Western Sydney, School of Science and Health, Australia; and 2 Royal Botanical Gardens, Sydney, Australia. 

p.holford @ uws.edu.au 

Orange jasmine, a common ornamental, is a favoured host of Diaphorina citri Kuwayama, the principal vector 

of Candidatus Liberibacter asiaticus, the most widespread of three liberibacters that cause Huanglongbing. 

Orange jasmine is also a transient host of the disease, but its identity has been subject to conjecture since 

1747. It is widely regarded as Murraya paniculata (L.) Jack, but also as Murraya exotica L. Our morphological 

(mostly leaves and leaflets) and molecular studies (6 chloroplast and the ITS rRNA operon regions) of the genus 

indicated that it is Murraya exotica, probably from Southern China/Northern Vietnam, and that Murraya 

paniculata represents a species that occurs in the Indonesian archipelago. The study also determined that 

a species, Murraya asiatica ineditus, previously regarded as Murraya paniculata, occurs in mainland Asia 

and that a fourth species, Murraya ovatifoliolata (Engl.) Domin., includes taxa formerly regarded as varieties 

of Murraya paniculata: Murraya ovatifoliolata var. ovatifoliolata ineditus (small and large leaflet forms in 

Australia) and Murraya ovatifoliolata var. zollingeri ineditus (from the eastern Indonesian archipelago). Two 

possible hybrids, Murraya × omphalocarpa ineditus from Orchid Island, Taiwan and Murraya × cycloopensis 

ineditus from Papua were identified. Murraya exotica is naturally associated with low altitude maritime and 

riparian acid red soils, and Murraya asiatica with limestone hills. Of the four identified species, Murraya 

exotica is the only one known to have been introduced to the Americas. There are no records of Murraya 

paniculata or Murraya asiatica as hosts of liberibacters, nor of Murraya asiatica as a host of Diaphorina citri. 

S12O05 

Effect of HLB on the expression of calcium signals related genes 

Parra C.C. 1 , Kunta M. 2 , and Louzada E.S. 1 

1 Texas A&M University-Kingsville (TAMUK), Citrus Center, USA; and 2 Texas A&M University- Kingsville (TAMUK), Citrus Center, USA. 

eliezer.louzada @ tamuk.edu 

Citrus has been challenged for a long time by innumerable biotic and abiotic threats, and it has so far survived. 

However, the introduction of the bacterium Ca. Liberibacter asiaticus (CLas), causal agent of citrus greening 


or Huanglongbing (HLB) and its vector, the Asian Citrus Psyllid (ACP), has completely changed this scenario 

and the industry now faces one of its worst nightmares. It is well know that Calcium is one of the most 

important elements in the plant that generate signals to be transduced into response to counteract basically 

any kind of biotic and abiotic stresses. No information is currently available on the effect that HLB has on 

genes regulating calcium signals, however, nutrient leaf analysis shown that Calcium is one the elements that 

is reduced upon CLas infection. The objective of this research is to study the effect of CLas infection on the 

expression of genes involved in Calcium dynamic in HLB infected Valencia sweet orange young and mature 

leaves, asymptomatic and symptomatic, compared to non-infected Valencia orange control. Results by realtime 

PCR obtained to date shows strong reduction in expression of a calcium ion channel in young and mature 

infected asymptomatic leaves compared to health control. Mature symptomatic leaves also had reduced 

expression compared to control, but more expression than young and mature asymptomatic leaves. -Results 

for expression of 15 genes involved in calcium signals will be presented. 

S12O06 

Transcriptional genomics and proteomics in citrus roots infected by Candidatus Liberibacter asiaticus. 

Zhong Y. 

Institute of Fruit Tree Research, Guangdong Academy of Agricultural Science (GAAS), Citrus Breeding, China. zhongyun99cn@163.com 

Jiangxired tangerine root samples at 50 wpi were used in RNA-sequencing. Some DEGs were confirmed by 

qPCR. Results showed that: 1) 3956 genes were differentially expressed, among which 1840 were up-regulated 

and 2116 down-regulated. 65 DEGs were identified with more than 10-fold changes. 2) SA signal transduction 

pathway related genes were up-regulated, the key gene of this pathway, NPR1 was up-regulated 1.6 times, 

and the downstream PR1 gene was up-regulated 2.4 times. 3) JA signal transduction pathway related gene 

didn’t have notable responses to HLB infection. 4) Sucrose invertase was up-regulated 1.7 times, while the 

sucrose synthase were down-regulated 1.8 times. This may indicate that the sucrose level in HLB infected 

roots decreased as result of plugged phloem. Furthermore, ferredoxin expression was down-regulated 2.2 

times, which may be related to nutrition deficiency, that is commonly associated with HLB infected trees. 

Comparative proteomic approach was also applied to decipher the pathogenic process of HLB in affected 

red tangerine roots using iTRAQ technique. Results showed that: 1) The 1445 identified proteins mainly 

ranged from 20 to 70kDa or larger than 100kDa. 2) plugged phloem related protein SEO was up-regulated by 

1.67 times, and this protein may function in inhibiting infection of the HLB bacteria and hampering the long 

distance transport of sucrose. Subtilisin-like protease was up-regulated with a fold change of 282.09 and the 

gene of this protein was also up-regulated 3.14times, which suggested that the enzyme play important roles 

in inhibiting the infection of HLB bacteria and protecting the root meristematic zone. 

S12O07 

Resistance and tolerance to Huanglongbing in citrus 

Stover E. 1 , McCollum G. 1 , Driggers R. 1 , Duan Y.P. 1 , Shatters, Jr. R. 1 , and Ritenour M. 2 

1 USDA/ARS, US Horticultural Research Laboratory (USDA/ARS, USHRL), USA; and 2 University of Florida, Indian River Research and 

Education Center (U of F, IRREC), USA. ed.stover @ ars.usda.gov 

Huanglongbing (HLB) is severely impacting Florida citrus. Productivity declines in many HLB-affected 

genotypes, often with greatly thinned canopies. Fruit size and quality are often adversely affected as the 

disease advances. HLB was assessed in diverse cultivars in commercial groves with high HLB-incidence. 

Temple had the lowest HLB symptoms and Liberibacter (Las) titer, while Murcott and Minneola had the 

highest. The USDA Ft. Pierce, FL farm is managed to reveal genotype responses to HLB. Some current cultivars 

and hybrid seedlings demonstrate resistance/tolerance, at least to strain(s) of Las present. C. trifoliata is the 

best documented citrus resistance source with Las titers suppressed even when C. trifoliata is grafted onto 

severely-infected rootstocks. Some cultivars and hybrids have abundant foliage symptoms, but full canopies 

and seemingly normal fruit set and size. In 3-years of data from a replicated trial of Triumph(T), Jackson(J), 

Flame(F), and Marsh(M), HLB symptoms were severe in all trees and Liberibacter titers were similar. However, 

F&M were almost completely defoliated in some years while T&J had full canopies. Cumulative fruit/tree was 


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greater for T&J (255&220) than for F&M (29&66). T&J fruit met commercial standards and had normal size 

but F&M fruit were unacceptable with many small and misshapen. Evidence mounts that useful resistance/ 

tolerance to HLB is present in cultivated citrus and this is a focus of the USDA citrus breeding program. 

S12O08 

A comparison of different methods to evaluate host resistance or tolerance to Huanglongbing, 

caused by Candidatus Liberibacter asiaticus. 


United States Department of Agriculture, Agricultural Research Service (USDA, ARS), United States Horticultural Research Laboratory, 

USA. kim.bowman @ ars.usda.gov 

One objective of the USDA-ARS citrus breeding program is the development of cultivars with resistance or 

tolerance to Huanglongbing (HLB) disease, caused by Candidatus Liberibacter asiaticus (Las). Both conventional 

breeding and transformation are being used to generate new clones that are tested for response to the 

pathogen. We will present the results from 20 separate experiments to test host resistance or tolerance to Las 

infection. Natural infection in the field occurs through the vector Asian Citrus Psyllid (ACP), but field infection 

is much slower than desired for efficient studies. Greenhouse inoculation through ACP or graft is much more 

controlled and rapid, but also presents certain challenges and limitations. In our studies, host trees that 

became infected with Las in the greenhouse and field developed symptoms that were measured, including 

effects on leaf morphology, tree growth, and cropping. Host gene expression and metabolic changes were 

studied, and specific responses documented. Measurements of Las bacteria titer over time were also used 

to assess the resistance or tolerance of the host. Typical susceptible cultivars became PCR positive for Las 

as early as 5-8 weeks after graft inoculation, while field infection of trees by even heavy populations of ACP 

could take 1-2 years or more. Symptom development typically lagged considerably behind PCR detection of 

the pathogen. Several host clones with resistance or tolerance to Las infection were included in the studies. 

S12O09 

Evaluation of transgenic citrus for disease resistance to HLB and Canker 

Dutt M. 1 , Barthe G.A. 1 , Orbovic V. 1 , Irey M. 2 , and Grosser J.W. 1 

1 University of Florida (UF), Citrus Research and Education Center, USA; and 2 United States Sugar Corporation, USA. manjul@ufl.edu 

Transgenic citrus scion and rootstock cultivars were transformed with gene(s) encoding antimicrobial peptides or 

systemic acquired resistance (SAR) proteins. Each gene was under control of an enhanced CaMV 35S promoter. 

Several genes were also under control of a phloem specific Arabidopsis SUC2 (AtSUC2) promoter. A number 

of clones of each transgenic line were evaluated for resistance to Huanglongbing (HLB, caused by Candidatus 

Liberibacter asiaticus) and Citrus Canker (caused by Xanthomonas citri ssp. citri). 600 trees planted in spring 

2009 in a heavily HLB and canker infected Martin County grove were tested using qPCR for infection to HLB 

after 30 months in field. 396 trees tested negative for the HLB bacterium. Approximately 200 PCR negative trees 

were observed to be healthy and flushing after 40 months in the field and were again evaluated using qPCR. 

In addition, we observed several trees containing one of our antimicrobial constructs to be tolerant to citrus 

canker. In a separate experiment, 345 transgenic trees and controls were placed in a greenhouse containing free 

flying HLB-infected Asian Citrus Psyllids (ACP) during April 2011. All trees were evaluated for infection after 12 

months by qPCR, and 80% of the transgenic trees tested negative for the bacterium. These results suggested 

that some of the antimicrobial peptides could provide varying levels of resistance against both HLB and canker. 

S12O10 

California’s response to the first detection of HLB. 

Luque-Williams M.J. 

California Department of Food and Agriculture (CDFA), USA. mlwilliams@cdfa.ca.gov 

Since the first detection of the Asian Citrus Psyllid in California in August 2008 (along the border with Mexico) 

the California Department of Food and Agriculture has implemented, in addition to the long-standing ACP 


trapping program, visual surveys, psyllid collections and chemical treatments within a 400m radius of all 

psyllid finds. Psyllids collected in these surveys were tested for HLB. Despite the surveys and suppression 

efforts within two years the psyllid had spread throughout five Southern California counties, principally in 

Los Angeles County, but not to the Central Valley where the majority of commercial citrus is located. In 

March 2012 a psyllid collected from a grafted pummelo (of unknown origin) during a visual survey in Los 

Angeles County tested positive for HLB, the first such find in California. Plant material collected from the 

tree (exhibiting classic HLB leaf symptoms) confirmed that the tree was positive for HLB. A trace forward and 

trace back of the HLB positive tree was initiated to determine the original source of the budwood of the HLB 

positive tree (as yet unsuccessfully). Eradication of the tree ensued paralleled by the CDFA developed HLBpositive 

protocol previously established. All citrus and citrus relatives, ACP nymphs and adults within a 800m 

radius were collected and tested. With the positive HLB find the Citrus Pest Disease Prevention committee, 

working with CDFA, has provided the funding for HLB testing of all host plants and ACP (adults and nymphs) in 

the first 500 m around the find every two months for a year and the testing of ACPs in the next 500m around 

the find and the host plants that show symptoms. To date no other HLB-positive psyllids or trees have been 

detected. 

S12O11 

Comparative study of different host range strains of Xanthomonas citri subsp. citri: Chemotaxis 

and biofilm formation. 

Sena M. 1 , Ferragud E. 1 , Redondo C. 1 , Johnson E.G. 2 , Graham J.H. 2 , Girón J.A. 3 , and Cubero J. 1 

1Instituto Nacional de Investigaciones Agrarias y Agroalimentarias (INIA), Plant Protection, Spain; 2University of Florida (UF-CREC), Citrus 

Research and Education Centre, USA; and 3University of Florida (UF-EPI), Emerging Pathogen Institute, USA. sena.marta @ inia.es 

Xanthomonas citri subsp. citri strain A (Xcc A) is one of the causal agents of Citrus Bacterial Canker (CBC). 

Bacterial strains within this species are classified according to differences in host range as well as phenotypic 

and genotypic characteristics. Xcc A has a broad host range within the genus Citrus and close relatives, whereas 

Xcc A* and Xcc a w strains are limited to Key Lime (Citrus aurantifolia). The aim of this study was to compare 

the chemotactic profile and biofilm formation of Xcc A, A* and A w strain types compared to Xanthomonas 

alfalfae subsp. citrumelonis, causal agent of Citrus Bacterial Spot, and Xanthomonas campestris, causal 

agent of Black Rot in crucifers. Our results suggest differences in the chemotactic profile between broad and 

limited host range Xcc strains and xanthomonads from other hosts. Differences in biofilm formation were 

found among the strains and the inoculated host. At the early stages of biofilm formation, Xcc A produced an 

interwoven fibrillar structure while Xcc a w fibres had a linear structure. TEM revealed that surface motility 

structures on cells varied; Xcc A formed lateral appendages at the edge of the bacterial colony while Xcc a w 

possessed a single polar flagellum. Purification and sequencing of Xcc surface proteins revealed the presence 

of type IV pilus associated with biofilm and twitching motility in other bacterial species. Current studies are 

focused on the role of this protein in biofilm formation and the possible differences among the Xanthomonas 

strains. 

S12O12 

A new minisatellite-based scheme for the global surveillance of Xanthomonas citri pv. citri, the 

causal agent of Asiatic Citrus Canker. 

Magne M. 1 , Leduc C. 1 , Vernière C. 1 , Vital K. 1 , Gordon J. 2 , Escalon A. 1 , Guérin F. 2 , Gagnevin L. 1 , and Pruvost O. 1 

1CIRAD (CIRAD), UMR PVBMT, Réunion, France; and 2Université de la Réunion, UMR PVBMT, Réunion, France. olivier.pruvost @ cirad.fr 

Xanthomonas citri pv. citri (Xcc), the causal agent of Asiatic Citrus Canker, is an internationally major bacterial 

pathogen currently not reported from countries in the Mediterranean basin, including the EU. Some 

pathological diversity among strains was reported, leading to the description in Xcc of pathotypes differing 

in host range and aggressiveness. Xcc is recognized as a monomorphic pathogen and the very low intrapathovar 

diversity at housekeeping genes precludes the use of the increasingly popular MLST (MultiLocus 

Sequence Typing) for the global molecular surveillance of Xcc. 


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We developed a new MLVA (MultiLocus Variable number of tandem repeats Analysis) scheme. It targeted 

51 minisatellite loci dispersed over the Xcc genome with tandem repeat size ranging from 10 to 217-bp, 

thus allowing the use of standard agarose gel electrophoresis in laboratories that are not equipped with a 

genotyper. Among these loci, 34 were found to be polymorphic within a strain collection composed of strains 

from all continents where Xcc has been recorded, including recent outbreaks in Africa where the bacterium is 

reemerging. This typing scheme displayed a maximal typeability and repeatability. The produced data support 

the usefulness of this new MLVA scheme for global surveillance of Xcc. 

S12O13 

Analysis of microRNAome of Chinese citron ‘C-05’ resistant to Citrus Canker disease. 

Dai S.M., Chen Y.M., Li D.Z., Li F., Yan J.W., and Deng Z.N. 

Hunan agricultural university, China. dsm531@126.com 

MicroRNAs (miRNAs) are small RNAs (sRNAs) 20-24 nucleotides in length, and commonly exist in organism. 

During the last 20 years, research on isolation and function identification of miRNAs made the people 

understand regulation of gene expression more deeply. Some research showed miRNAs played important 

role in resistant response of plant to pathogenic bacteria. Citrus Canker is a quarantine bacterial disease, 

which seriously affect the development of citrus industry. By field trials for many years, we obtained a 

special material (‘Chinese Citron’ C-05) resistant to citrus canker which would provide a good base to carry 

on the research about resistance of citrus to this disease. In this research, Illumina/Solexa deep sequencing 

technology was applied to analyze microRNAome of Chinese Citron C-05 and susceptible Bingtangcheng 

(as control). Comparing with Bingtangcheng, miRNAs profile of Chinese Citron C-05 had 69 miRNAs only 

expressed before inoculation of pathogen bacteria, 64 miRNAs after inoculation and before appearance of 

hypersensitive necrosis reaction, 74 miRNAs after appearance of reaction. Moreover, through prediction 

and function analysis of target genes, results showed 69 metabolic pathways were regulated by these 

differentially expressed miRNAs only in Chinese Citron C-05. Among these pathways, we were interested in 3 

pathways related to plant resistance which were helpful to reveal molecular mechanism of ‘Chinese Citron’ 

C-05 resistant to citrus canker. Now, we were verifying miRNAs regulated these 3 pathways and expression of 

target genes. 

S12O14 

The role of auxin in the citrus defense to early infection by Xylella fastidiosa. 

Rodrigues CM, Souza AA, Takita MA, and Machado MA. 

Centro de Citricultura Sylvio Moreira, IAC, Laboratory of Biotechnology, Brazil. marcos@centrodecitricultura.br 

Many studies have shown the involvement of plant hormones in plant responses to biotic and abiotic 

stresses. Recent studies indicate that auxin has an important role in in stress responses. Previous results 

from our group showed induction of some genes involved in auxin pathway in Ponkan mandarin (Citrus 

reticulata Blanco), tolerant to citrus variegated chlorosis, one day after challenge with X. fastidiosa, the 

causal agent of this disease. Thus, the study aimed to evaluate the differential expression of some genes 

involved in this pathway in mandarin and the susceptible sweet orange (Citrus sinensis L. Osb) in early 

stage of infection. The genes evaluated were: IAA9 (Aux/IAA), ARF6, TIR1, UBA1, UBC2, E3, SKP, and BIG. 

The RNAs from mandarin and orange infected or not (control) with the bacteria were extracted. RT-qPCR 

analyses were carried and as a result, all genes were significantly induced in mandarin. However, in sweet 

orange it was observed significant induction just for UBC2 and UBA1 genes. Because there was also a 

repression in expression of E3, SKP, and ARF6, ubiquitination may be involved in other pathways. It was 

evident in this work the importance of differential expression of genes involved in auxin metabolism in 

resistance and susceptibility to X. fastidiosa of mandarin and orange, respectively. In addition, the results 

indicate that this pathway plays an important role in the defense response of mandarin in the initial stage 

of infection by X. fastidiosa. 

Financial Support: INCT Citros (Fapesp and CNPq). 


S12P01 

Yield loss modeling of “Candidatus Liberibacter asiaticus” on Persian lime (Citrus latifolia) in 

southern Mexico 

Flores Sanchez J.L. 1 , Mora Aguilera G. 1 , Loeza Kuk E. 2 , Domínguez Monge S. 1 , Acevedo Sánchez G. 3 , and López Arroyo J.I. 4 

1 Colegio de Postgraduados (Colpos), Fitopatología, México; 2 INIFAP-Campo Experimental Mocochá, Yucatán (INIFAP), Fitopatología, 

México; 3 Laboratorio de Análisis Epidemiológico de Plagas Reglamentadas (SINAVEF Lab), Fitopatología, Colpos, México; 4 INIFAP 

-Campo Experimental General Terán, Nuevo León (INIFAP), Entomología, México. flores.jorge@colpos.mx 

In Mexico, Huanglongbing caused by Candidatus Liberibacter asiaticus (Las) was detected in Yucatan in 2009 

mainly on Citrus latifolia and C. aurantifolia. An early infected Persian lime orchard was selected to estimate 

the yield loss caused by Las for purpose of decision making on disease management. A restricted random 

block design with paired healthy and diseased trees, verified by real time PCR, was established to assess 

eight morphologic and organoleptic fruit variables in 2011. Weight, size, peel thickness, juice volume and pH 

were statistically higher on healthy trees (T1) and asymptomatic branches (T3) of positive trees with regard to 

symptomatic branches (T2) (Tukey, p= 0.05). Differences were not found between T1 and T2 with exception 

of fruit size. Brix and titratable acidity were not different on any treatment. Las induced higher detrimental 

effect on weight (17.3%) and juice volume (18.6%) being dependent on disease severity (x) (0=healthy, 1=25, 

2=50, 3=75, 4=100% canopy symptoms): Yweight = 217.2-4.2x 0.03x 2 , R 2 = 0.86; Yvolume = 645.4-11.7x 0.09x 2 , 

R 2 = 0.82. Yield detrimental effect was associated with bacterial concentration base on its relationship with 

severity: Y[bacteria] = 1.174 0.8x-0.0067x 2 , R 2 = 0.91. HLB-Per 1.0, a MS Excel program, was developed to 

estimate the impact on production and profit considering different Las infection periods. The model was also 

validated with C. aurantifolia. This is the first yield loss report on Persian lime. 

S12P02 

Seasonal detection of Huanglongbing symptomatic trees and Diaphorina citri in citrus groves in 

Sao Paulo State, Brazil 

Bassanezi R.B. 

Fundo de Defesa da Citricultura (Fundecitrus), Departamento Científico, Brazil. rbbassanezi@fundecitrus.com.br 

Citrus Huanglongbing (HLB) was first reported in Sao Paulo State (SPS), Brazil, in 2004 and since that the 

management of this disease has been based on detection and elimination of symptomatic trees and monitoring 

and control of the insect vector Asian Citrus Psyllid (ACP), Diaphorina citri. To maximize the labor and financial 

resources for best HLB management it is important to determine the periods when HLB-symptomatic trees and 

ACP are detected by scouting teams in the field. To analyze the seasonality of HLB-symptomatic trees detection, 

data of monthly scouting of 100% of citrus trees in all citrus blocks of 24 citrus groves in 20 municipalities of 

Southern, Southwestern, Eastern and Center regions of SPS, from 2005 to 2011, were used. For ACP, data of 

fortnightly assessments of yellow stick traps placed in four groves without insecticide application in Eastern 

and Center regions of SPS, from 2005 to 2011, were used. Although HLB-symptomatic trees were detected in 

all months, 79% of total amount of detected diseased trees was found from February to August and less than 

10% from October to December. ACP was also detected in all months, but there were two picks of detection in 

October and December, corresponding to spring and summer main citrus vegetation. More than 80% of ACP 

was detected from August to January. Due to the simultaneous presence of considerable amount of ACP and 

symptomatic trees in August and January, these months could be key periods for HLB management. 

S12P03 

Identification of ”Candidatus Liberibacter” and phytoplasma and evaluation of their association 

with citrus Huanglongbing in China 

Su H.N., Wang X.F., Tang K.Z., Li Z.A., and Zhou C.Y. 

National Engineering Research Center for Citrus, Citrus Research Institute, Southwest University, College of Plant Protection, China. 

huanansu211@163.com 

Citrus Huanglongbing (HLB) is one of the most devastating citrus diseases worldwide. Prior to 2004, 

“Candidatus Liberibacter” spp. was considered as the putative causal agents of HLB, though Koch’s postulates 


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have not been completely fulfilled. Pigeon pea witches’-broom phytoplasma and Aster yellow phytoplasma 

were detected from citrus samples with characteristic HLB symptoms from Brazil and China, respectively. 

These two phytoplasmas might also be associated with HLB. In order to elucidate the “Ca. Liberibacter” spp. 

and the phytoplasma association with HLB in the P. R. China, 472 samples were collected from Guangdong, 

Guangxi, Yunnan, Guizhou, Sichuan, Chongqing, Jiangxi, Fujian, and Zhejiang Provinces from 2008 to 2011. The 

symptoms included leaf chlorosis, blotchy mottle, midrib yellowing, zinc nutritional deficiency, iron nutritional 

deficiency and fruit colour inversion. Using primer set OI1/OI2c, PCR products digested with Xba were used 

for identifying “Ca. Liberibacter asiaticus” and “Ca. Liberibacter africanus”. Primer set GB1/GB3 was used for 

the detection of “Ca. Liberibacter americanus”. Nested PCR with phytoplasma-universal primer sets P1/P7 

with fU5/rU3 and R16mF2/R16R1 with R16mF2n/R16R2 were used for the detection of phytoplasma. Of the 

472 samples, 261 were positive for “Ca. Liberibacter asiaticus”. Samples with symptoms of blotchy mottle, 

zinc nutritional deficiency and fruit colour inversion had higher detection rate than those one with other 

symptoms. However, all samples were negative for “Ca. Liberibacter africanus”, “Ca. Liberibacter americanus” 

and phytoplasma. Our results suggested that “Ca. Liberibacter asiaticus” was highly associated with HLB in 

China, and phytoplasmas might not be closely related with the etiology of HLB. 

S12P04 

Rapid on site detection of the HLB/Citrus Greening causal agent “Candidatus Liberibacter 

asiaticus” by AmplifyRP, a novel rapid isothermal nucleic acid amplification platform. 

Russel P. 1 , Amato M. A. 2 , and Bohannon R. 1 

1 Agdia Inc., United States; and 2 Agdia Biofords, France. marcos.amato@biofords.com 

Huanglongbing (HLB), also called Citrus Greening, has become the most serious threat to the citrus industry 

worldwide. Although the disease first emerged in the southeastern part of Asia, it is now well established all 

along the American continent, including Brazil, Florida and California which are the world most important citrus 

production areas. In the Asian and American continents the disease is associated with the insect-vectored, 

obligate intracellular bacterium “Candidatus Liberibacter asiaticus”. The bacterium resides in the host phloem 

cells and it is transmitted by the Asian Citrus Psyllid, Diaphorina citri. Early pathogen detection is the key success 

factor to protect free areas from pathogen introduction. Unfortunately, the disease has a long incubation period, 

during which pathogen concentration is very low and non-systemically distributed. This makes diagnostic, disease 

control and eradication programs extremely difficult. Early detection is not possible by using traditional serological 

methods. Agdia has recently developed a new rapid molecular detection technique, AmplifyRP, allowing PCRlevel 

sensitivity detection within minutes, in the field. AmplifyRP uses a Recombinase-polymerase methodology 

for DNA amplification at a single temperature. In contrast to conventional or real-time PCR, AmplifyRP has no 

DNA purification requirements, requires no thermocycling, and results can be read using small and user-friendly 

devices. A portable florescence reader or a lateral flow device (similar to Agdia’s ImmunoStrip®) can be used to 

visualize results in as little as 30 minutes, compared to several hours for conventional PCR. AmplifyRP eliminates 

the need for expensive PCR equipment, a large number of chemicals reagents, and the need for technically 

trained staff. Given its characteristics, AmplifyRP is the ideal tool to monitor HLB progression by early detection 

of “Ca. Liberibacter asiaticus” in citrus trees or in vector insects. 

S12P05 

Diversity of “Candidatus Liberibacter asiaticus”, “Candidatus Liberibacter africanus” and 

“Candidatus Liberibacter americanus” based on 23S/5S rDNA sequences 

Liao H. 1 , Bai X. 2 , Li Y. 3 , Chen C. 4 , Yang L. 5 , Xu N. 6 , Huang H. 6 , and Wang X. 6 

1 Horticulture Research Institute of Guangxi Academy of Agricultural Sciences (HRIGAAS), Citrus Research Group, China; 2 Department 

of Agriculture of Guangxi (DAG), Citrus Research, China; 3 Guangxi Crop Genetic Improvement and Biotechnology Lab (GCGIBL), 

Citrus Research, China; 4 Guangxi Citrus Research Institute (GCRI), Citrus Breeding, China; 5 State Key Laboratory of Subtropical 

Agro-Bioresources Conservation and Utilization (SKLSACU), Citrus Research, China; and 6 Horticulture Research Institute of Guangxi 

Academy of Agricultural Sciences (HRIGAAS), Citrus Research Group, China. liaohuihong2001@gmail.com 

Primers based on the 23S/5S rDNA conserved sequences of “Candidatus Liberibacter asiaticus” (Las), 

“Candidatus Liberibacter africanus” (Laf) and “Candidatus Liberibacter americanus” (Lam) were designed to 


amplify different geographical Huanglongbing affected citrus samples. The PCR products were sequenced and 

the diversity of different strains was studied. The results showed that the amplified size is 1654 bp including 

5S rRNA gene for six strains from Guangxi, Fujian, Hunan, Taiwan, 1648-1650 bp including 5S rRNA gene 

for four strains from South Africa, 1635 bp including glpK gene and 5S rRNA gene for six strains from Brazil, 

respectively. The strains from Brazil shared 94.1%-94.3% of sequence identity with Las, 94.0-94.2% with Laf 

and 99.8%-100% with Lam. The strains from South Africa shared 97.4%-97.5% of sequence identity with Las, 

99.9-100% with Laf and 94.1%-94.2% with Lam. The strains from China mainland, Taiwan and Florida shared 

99.8%-100% of sequence identity with Las, 97.3-97.5% with Laf and 94.2%-94.4% with Lam. Total 4 bps of 

glpK sequence were mutant among three strains from Brazil, but only two amino acids were changed. A 

phylogenetic tree was constructed for the 16 strains and other proteobacterias based on the 23S/5S rDNA 

sequences. The results showed that the strains from Brazil were clustered with Lam, those from South Africa 

clustered with Laf, and those from China mainland, Taiwan and Florida clustered with Las. 

S12P06 

Phloem anatomy of citrus trees: healthy vs HLB affected 

Etxeberria E., and Narciso C. 

University of Florida, Citrus Research and Education Center, USA. eetxeber@ufl.edu 

Phloem cells of HLB-affected trees become obstructed with callose, P-protein plugs, and in some instances, 

starch grains. The presence of these plugs is believed to hinder the transport of photoassimilates (nitrogenous 

and reduced carbon compounds) to the root system. However, even with a seemingly collapsed phloem tissue, 

citrus trees remain viable and produce fruit for some time, suggesting either incomplete plugging of phloem 

elements or the existence of alternative routes for photoassimilate transport. In this study, we examined 

the basic structure of phloem tissue from HLB-unaffected and HLB-affected trees under light and scanning 

electron microscopy. To avoid any possible interference with callose induced by injury during sampling, we 

employed freeze substitution technique. Sieve elements from HLB-unaffected trees show sizable lateral pit 

fields to phloem and ray parenchyma. The cells have very angular sieve plates and appear relatively clean 

from cellular components. Sieve pores are of approximately 0.1-0.5 μm in diameter. HLB-affected phloem 

cells contain massive amounts of amorphous material clearly traversing sieve plates and lateral pit fields. 

Eventually, the walls thicken and cells totally collapse into an almost solid cell wall barrier. Occasionally, 

wound phloem appears along the petiole cortex in HLB-affected trees. Most notable is the large number 

of wall perforations all along the cortex parenchyma with abundant pit fields. These anatomical features 

of the parenchyma cells provide an alternative route that would allow movement of photassimilates from 

photosynthetic cells through cortex and ray parenchyma. 

S12P07 

Anatomical comparison of HLB-affected sweet orange and rough lemon 

Fan J. 1 , Chen C. 2 , Gmitter Jr. F.G. 2 , Achor D.S. 2 , Brlansky R.H. 2 , and Li Z.G. 1 

1 Chongqing University, Key Laboratory of Biorheological Science and Technology, China; and 2 University of Florida - Citrus Research 

and Education Center, USA. fgmitter@ufl.edu 

Citrus Huanglongbing (HLB) is considered the most serious problem for citrus production. There is no known 

resistant germplasm although some citrus types appear to be more tolerant and/or insensitive to the disease, 

exhibiting slow decline and rejuvenating capability. To understand the underlying mechanisms, symptomatic, 

asymptomatic, and healthy leaf, stem and root tissues from sensitive sweet orange and tolerant rough lemon 

were compared using light and transmission electron microscopy. Phloem collapse, plugged sieve elements 

and accumulation of starch were observed in leaf petioles of symptomatic leaves from both HLB-diseased 

rough lemon and sweet orange, compared with their own mock-inoculated controls. In symptomless leaves, 

significant anatomical changes (e.g. phloem cell collapse and starch accumulation) were found in HLBdiseased 

sweet orange, but not in rough lemon. Furthermore, starch depletion and phloem fiber degradation 

were observed in secondary roots of diseased sweet orange, but not in rough lemon. In young green stems, a 

few plugged sieve elements were seen in both diseased rough lemon and sweet orange, but starch deposition 


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only occurred in the latter. Taken together at the whole plant level, HLB infection induces fewer and less severe 

anatomical changes in rough lemon than in sweet orange. In particular, the absence of obvious changes in 

the rough lemon root system is suggested to be critical for sustaining plant growth after infection, and should 

greatly contribute to its HLB tolerance. 

S12P08 

The significance of early root infection in Huanglongbing disease development and crop loss 

Johnson E.G., Bright D.B., and Graham J.H. 

University of Florida (UF-CREC), Citrus Research and Education Center, USA. egjohnson@ufl.edu 

Huanglongbing (HLB) is a systemic disease of citrus caused by the phloem-inhabiting bacterium “Candidatus 

Liberibacter asiaticus” (Las). Disease in grove trees is initially identified by foliar symptoms, most commonly 

blotchy mottle. Detection of Las in leaf tissue by qPCR early in disease development is usually limited to 

symptomatic leaves and proximal young leaves. Over multiple years, disease symptoms and detectable Las 

spread to the rest of the canopy. A negative exponential relationship observed between canopy disease severity 

and yield decline indicates larger than expected crop loss when symptoms are limited to one or a few branches. 

Observations in potted and grove trees revealed that Las is frequently detectable in roots months before 

detection of Las in leaves and foliar symptom development. Asymptomatic and recently symptomatic grove 

trees with Las detected in root tissue have from 26-46% lower root density compared to apparently healthy 

trees. These results suggest that early infection of roots by Las causes root damage before the appearance 

of foliar symptoms and is associated with the larger than expected yield reduction on trees with initial foliar 

symptoms. Further understanding of the early effects of Las infection on roots and HLB tree decline is needed. 

S12P09 

Monitoring “Candidatus Liberibacter asiaticus” in a commercial orchard of sweet orange and 

‘Tahiti’ lime in the northwest of Paraná State 

Sauer A.V. 1 , Nocchi P.T.R. 1 , Zanutto C.A. 1 , Rinald D.A.M.F. 2 , and Nunes W.M.C. 1 

1 Universidade Estadual de Maringá (UEM), Nucleo de Pesquisa em Biotecnologia Aplicada (NBA) - Centro de Ciências Agrárias (CCA), 

Brazil; and 2 Secretaria de Estado da Agricultura e Abastecimento (SEAB), Brazil. alinevanessasauer@hotmail.com 

Huanglongbing (HLB) stands out as one of the most devastating citrus diseases worldwide, affecting several 

species of citrus. The symptoms are characterized by branches with yellow leaves, usually isolated in plants. 

The objective of this study was to evaluate the population behavior of the bacterium “Candidatus Liberibacter 

asiaticus” in a commercial orchard. Plants of sweet orange and ‘Tahiti’ lime naturally infected with HLB were 

protected with aphid-proof screens to prevent the spread of disease in the area, after confirmation of diagnosis 

by conventional PCR. The bacterial population monitoring was performed by real-time PCR after total DNA 

extraction from main veins of symptomatic leaves collected monthly, for twenty months. In each plant, four 

samples were collected and analyzed from the quadrants of the tree. In the species studied erratic behavior of 

the bacteria were observed. Even after detection in one quadrant of the plant, after a few months it was not 

possible to verify the presence of the etiologic agent in the same place. For the sweet oranges, the quadrants 

that expressed more severe symptoms, showed the greater amount of bacteria, with the Ct between 18 and 33. 

For the ‘Tahiti’ lime similar results to those described for sweet oranges were found. These results contribute to 

the study of the epidemiology of HLB in this crop and helps to the search for effective control measures. 

S12P10 

Multiplication of “Candidatus Liberibacter asiaticus” in Citrus sinensis, Citrus sunki, Poncirus 

trifoliata and hybrids obtained from crosses between Citrus sunki and Poncirus trifoliata 

Boava L.P., Cristofani-Yaly M., Coletta Filho H.D., Bastianel M., and Machado M.A. 

Centro de Citricultura Sylvio Moreira, Instituto Agronômico, Brazil. mbastianel@centrodecitricultura.br 

Huanglongbing (HLB) is caused by a phloem-limited bacterium and can be transmitted by both psyllid 

vector and graft propagation. “Ca. Liberibacter asiaticus” (Las) is the most widespread specie in Brazil and 


affects all known citrus species and relatives. However, there are reports that some genotypes are slower to 

develop HLB symptoms. In this work, we examined the Las multiplication in 3 genotypes (C. sinensis, C. sunki 

and P. trifoliata) and 10 hybrids obtained from crosses between C. sunki and P. trifoliata. All genotypes (3 

biological replicates) were graft inoculated with budwood from HLB-infected plants and kept under controlled 

conditions. At 60, 90 and 120 days after grafting, leaves were collected for DNA extraction from leaf midrib. 

qPCR reactions were carried out using TaqMan® PCR system with different primers-probes previously 

described (16S rDNA, elongation factor Ts and prophage region hyvI and hyvII) and 18S and cytochrome 

oxidase were used as internal control. Although Las was able to multiply in all of the plants, a wide range of 

responses was observed among different hosts. The infection rate was higher in C. sinensis and C. sunki in 

relation to P. trifoliata. Variability was observed in relative Las concentration among the 10 hybrids tested 

with some of them showing high Las concentration and others significantly lower levels of Las. These tolerant 

hybrids have been valuable for ongoing work in functional genomics, genetic mapping and eQTL studies. 

S12P11 

Low titers of “Candidatus Liberibacter asiaticus” in citrus plants exposed to high temperatures 

result in low acquisition rates of the bacterium by the insect vector Diaphorina citri 

Lopes S.A., Luiz F.Q.B.Q., Martins E.C., Fassini C.G., and Sousa M.C. 

Fundo de Defesa da Citricultura (Fundecitrus), Científico, Brazil. slopes@fundecitrus.com.br 

In Brazil, HLB is associated to “Ca. Liberibacter americanus” (Lam) and “Ca. Liberibacter asiaticus” (Las), 

with Las being now the most prevalent species. First found in 2004 in the center of São Paulo state HLB 

progressed faster and reached higher incidences towards the south. Since in the south summer temperatures 

are relatively milder and water deficit lower than those in the north, the environment could be playing a role 

on HLB spread. In fact, exposing infected trees to daily regimen of 24-38°C led to elimination of Lam and to 

a significant reduction in Las titer in the exposed trees (Plant Dis. 93:257-262). To gain more information on 

this, Las-infected graft-inoculated ‘Valencia’ plants at early, medium or late infection stages were pruned. 

One group was kept in the greenhouse (GH), an environment favoring Las infection, and the other in a growth 

chamber (GC) programmed to 24-38°C daily regimen. After 15, 30 and 60 days groups of 7 plants each were 

removed from GH and GC. Non-infective adult D. citri were caged at the tip of the new developing flushes. 

Two days later insects and flushes were processed and analyzed by qPCR. Incidence of Las-positive flushes 

and Las titer (in log of Las genome/g tissue) were lower on the GC- (64.9%; 4.9log) than on the GH-incubated 

(89.1%; 5.9log) plants. Similarly, the incidence of Las-carrying insects and Las titer (in log of Las genome/ 

lot 5 insects) were lower on those caged on GC-incubated (29.3%; 3.1log) than on those caged on the GHincubated 

(72.8%; 3.5log) plants. Data will be presented and their implication on the HLB epidemic discussed. 

S12P12 

Pre-inoculation with virus and citrus viroids in “Candidatus Liberibacter” infection and HLB symptoms 

Carvalho S.A., Silva L.F.C., Souza M.C.S., Francisco C.S., and Coletta-Filho H.D. 

Instituto Agronômico (IAC), Centro de Citricultura Sylvio Moreira, Brazil. sergio@centrodecitricultura.br 

Synergistic or antagonistic interactions among microorganisms may affect its development in many plant hosts, 

including suppression or increase in diseases expression. The objective of this research was to evaluate the 

effect of pre-inoculation with five isolates of different severity of Citrus Tristeza Virus (CTV) in the infection of 

“Candidatus Liberibacter asiaticus” (Las) and symptoms of Huanglongbing (HLB). Additionally were included 3 

treatments with CTV isolates of medium severity, infected also with Citrus Psorosis Complex Virus (Psorosis), 

Citrus Exocortis Viroid (CEVd) or Citrus Cachexia Viroid (CCaVd). The sources of viruses and viroids were plants 

of the IAC-Citrus Active Germplasm Bank, previously characterized by biological indexing. The experiment was 

conducted in greenhouse using nine months old nursery-trees of healthy ‘Pera’ sweet orange on ‘Rangpur’ lime. 

Viruses were bud inoculated in the canopy trunk using 12 plants per treatment, and seven months later, after 

confirmation of CTV infection by ELISA, Las was bud inoculated in 10 of them. It was evaluated the incidence 

and intensity of symptoms of HLB in leaves, being the presence of bacteria confirmed by PCR. In asymptomatic 

plants Las was also monitored by qPCR. Results obtained at 7, 14 and 21 months after inoculation with Las does 


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not indicate effect of the previous presence of CTV in Las infection and HLB symptoms, with similar proportion 

in treatment with viruses (68%) and without viruses infection (60%). On the other hand, mild (“PIAC”) or of 

medium severity (“CV 154”) isolates of CTV, showed the lowest rate of occurrence of HLB (30-40%), which 

reached 70-80% when plants were pre-inoculated with the severe CTV isolates “Capao Bonito” “CV 93” and 

“Barao B”. The pre-inoculation of isolates of medium severity of CTV: “CV 104”, “CV 155” and “CV 27”, also 

carrying respectively CCaVd, Psorosis and CEVd, induced 70, 80 and 100% of HLB symptoms. 

Financial support: Fundag, FAPESP and CNPq. 

S12P13 

The efficient transmission of “Candidatus Liberibacter americanus” from periwinkle 

(Catharanthus roseus) to different citrus genotypes by dodder 

Francisco C.S., Locali E.C., Machado M.A., and Coletta-Filho H.D. 

Centro APTA Citros Sylvio Moreira (IAC), Laboratório Biotecnologia, Brazil. carolinaf@centrodecitricultura.br 

In Sao Paulo State, Brazil, both bacteria “Candidatus Liberibacter asiaticus” (Las) and “Ca. L. americanus” (Lam) 

are associated with Huanglongbing - HLB or Greening disease in citrus. Nowadays Lam has been observed in 

low prevalence in HLB-disease plants, contrary to its high prevalence in the first 2 years of disease outbreak, 

2005 and 2006. But despite of this drastic swift on prevalence of “Ca. Liberibacter” species scientific interests 

remain on Lam bacteria. Based on our experience and supported by the Lopes & Frare (2008) data, Lam grafting 

transmission is randomly and not efficient for most citrus species, which increases difficulties in experiments 

under controlled conditions aiming to study plant-pathogen interaction. But, similarly to Asiatic species of Ca. 

Liberibacter, Lam reached high titers in periwinkle plants (Cataranthus roseus). The main objective of this study 

is to analyze the transmission of Lam from periwinkle to citrus by dodder (Cuscuta spp.) as an alternative to 

improve the transmission efficiency of that pathogen. Periwinkle seedlings infected with Lam were used as 

source for bacterial acquisition by dodder. After a period of 15 days parasitizing periwinkle plants, the dodder 

were keep connected to citrus plants by 30 days for the transmission. The citrus plant tests were analyzed by 

end-point PCR and qPCR. The results show that ‘Ponkan’ mandarin (Citrus reticulata) and ‘Dourada’ lime (Citrus 

limettioides) were infected at rate of 100%, while ‘Hamlin’ sweet orange (Citrus sinensis) of 75%, and ‘Key’ lime 

(Citrus aurantifolia) of 50%. However, the back transmission of Lam from periwinkle to citrus by dodder is an 

efficient strategy to be used for overcoming the low rate of transmission of this pathogen by grafting. 

S12P14 

Population dynamics of Diaphorina citri (Hemiptera: Psyllidae) in orchards of ‘Valencia’ sweet 

orange, ‘Ponkan’ mandarin and ‘Murcott’ tangor trees 

Beloti V.H. 1 , Felippe M.R. 2 , Rugno G.R. 1 , do Carmo-Uehara A. 2 , Garbim L.F. 2 , Godoy W.A.C. 1 , and Yamamoto P.T. 1 

1 Escola Superior de Agricultura Luiz de Queiroz (ESALQ), Entomologia e Acarologia, Brazil; and 2 Fundo de Defesa da Citricultura 

(Fundecitrus), Científico, Brazil. pedro.yamamoto@usp.br 

Huanglongbing (HLB), a destructive disease of citrus, is caused by endogenous, sieve tube-restricted bacteria, 

named Candidatus Liberibacter species. Diaphorina citri (Hemiptera: Psyllidae) is a vector of the bacteria in 

Asia and America. The purpose of this work was to study the population dynamics of D. citri in orchards of 

‘Valencia’ sweet orange, ‘Ponkan’ mandarin, and ‘Murcott’ tangor trees located at the São José farm in the 

municipality of Taquaritinga, SP, Brazil. Yellow sticky traps were used to monitor the vector. The largest number 

of D. citri was captured on the ‘Ponkan’ trees followed by the ‘Murcott’ and ‘Valencia’ sweet orange. Chemical 

pest control and environmental factors are likely to be responsible for this result. Pearson’s correlation analysis 

indicated that there is a weak correlation between the abundance of D. citri and the environmental factors 

of temperature and precipitation. An analysis of variance suggested that there was a significant difference 

in the abundance of D. citri among the three citrus tree varieties, and the autocorrelation was significant for 

the ‘Valencia’ orange orchard. Spectral analysis indicated that there were greater frequencies of peaks in 

the ‘Ponkan’ mandarin and ‘Murcott’ tangor trees, and the simulations performed using a stochastic logistic 

model suggested that the psyllid populations on orange trees are the most susceptible to local extinction; this 

result likely occurred because of the high levels of chemical control applied to orange trees. 


S12P15 

Systemic insecticides are effective in preventing the transmission of “Candidatus Liberibacter 

asiaticus” by Diaphorina citri? 

Yamamoto P.T. 1 , de Miranda M.P 2 , and Felippe M.R. 2 

1 Escola Superior de Agricultura Luiz de Queiroz (ESALQ), Entomologia e Acarologia, Brazil; and 2 Fundo de Defesa da Citricultura 

(Fundecitrus), Científico, Brazil. pedro.yamamoto@usp.br 

The purpose of this study was to evaluate the effectiveness of soil-applied systemic insecticides in the 

control of Asian Citrus Psyllid (ACP) Diaphorina citri and thereby prevent the transmission of “Candidatus 

Liberibacter” spp. in citrus bearing trees. The experiments were conducted in farms located in the region of 

Araraquara, SP, Brazil. The first experiment was carried out in 7-year-old ‘Valencia’ sweet orange on ‘Swingle’ 

citrumelo, with application in Aug/2009. The second and third were conducted in 8-year-old ‘Pera’ sweet 

orange on ‘Rangpur’ lime, in sandy and clay soil, with application in Nov/2009 and in Feb/2010. In the first 

experiment, the insecticides were effective in controlling ACP. Thiamethoxam at doses of 0.31 and 0.62 g ai/m 

of plant height and imidacloprid at a dose of 1.2 g ai/m were effective. Application with a volume of 1 liter/ 

plant and applied to the soil at the base of the trunk was more efficient compared with 0.5 L and application 

in the projection of the canopy. For applications done in Nov/2009 and Feb/2010 systemic insecticides were 

not effective in controlling ACP. The concentration of thiamethoxam (0.31 g/m) reached 1000 ppb in the first 

experiment; however, when applied in the other two experiments, was less than 200 ppb. The answer to the 

question is yes, because the systemic insecticides are efficient to control ACP. However, in some conditions 

they are not absorbed and translocated into the citrus trees, showing low efficiency. 

S12P16 

Vector control and foliar nutrition for management of Huanglongbing in Florida citrus 

Stansly P.A., Arevalo H.A., Qureshi J.A., Jones M., Hendricks K., Roberts P.D., and Roka F.M. 

University of Florida (IFAS), SW Florida Research and Education Center, USA. pstansly@ufl.edu 

Vector control and foliar nutrition are widely employed in Florida citrus to respectively slow the spread of 

HLB and mitigate effects of the disease on citrus trees. A replicated field study was conducted in a 13-acre 

commercial block of young ‘Valencia’ through four harvests employing a factorial design to evaluate individual 

and compound effects of a popular nutrient/SARs program and threshold-based vector management. Asian 

Citrus Psyllid populations were maintained at contrasting levels in insecticide-treated and untreated plots despite 

proximity. Nevertheless, incidence of HLB, estimated by PCR at near 30% at the beginning of the study, rose to 

over 90% early in the third year without significant contribution from vector control. However, yields were 

significantly improved all four years by the combined effects of nutrition and vector control, with a significant 

contribution from nutrition in the fourth year when production in the combined treatment approached the 

pre-HLB regional average. Economic analysis showed that, while the insecticide nutritional treatment produced 

the highest gain in production, it would not have been profitable at current juice prices. Fine tuning by reducing 

costs of the nutrient package and/or the insecticide regime could have made the program profitable, as could 

higher margins of a fresh fruit market. Further research is necessary to establish economic thresholds for both 

insecticide and nutrient application under different market and environmental conditions. 

S12P17 

Foliar spray of nutrients and growth regulators on the management of citrus affected by HLB – Is 

it possible? 

Medina C.L. 1 , Bataglia O.C. 2 , Furlani P.R. 2 , Machado R.S. 2 , and Creste A. 3 

1 Grupo de Consultores em Citros (GCONCI), Research, Brazil; 2 Conplant - Consultoria, Treinamento, Pesquisa e Desenvolvimento 

Agrícola LTDA (Conplant), Research, Brazil; and 3 Fazenda São José (FSJ), Manager, Brazil. clmedina@conplant.com.br 

The phloem of HLB affected plants are obstructed by callose that inhibit carbohydrates, minerals and water 

flow to the newer developing tissues. This causes damages to plant development, debilitates the plants 

and thus reduces the yield. The callose phloem obstruction may be related with the reaction defense 


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mechanism against “Candidatus Liberibacter asiaticus”. In many tree species the variations on phloem callose 

concentrations are related to the natural alterations of hormonal cytokinins and auxins levels. In order to 

verify if plant growth regulator (PGR) could have any effects on the HLB incidence (I) and severity of HLB 

(S), orange trees were treated with a foliar nutrient solution containing macro and micronutrients plus 

dimethylammonium (2,4-dichlorophenoxy) acetate with auxinic function. This treatment (PhT) started in the 

spring and continued during the summer with six applications. At one tested site a block with 18 % of affected 

plants I was reduced to 1.0% and this level persisted during the following year, while control blocks treated by 

the conventional treatment (vector control and elimination of all symptomatic plants), CT, I increased to 4 %. 

In another treated site, I of PhT was 1.7% while in CT was 2.9% and S was 2.7 and 5.6 respectively. The results 

are very encouraging and open an attractive possibility to the development of treatments with nutrient and 

PGR to reduce HLB symptoms keeping normal function of citrus trees. 

S12P18 

Antibiotic therapy of citrus bud wood for the management of Huanglongbing disease 


Institute of Horticultural Sciences, University of Agriculture (IHS UAF FSD PK), Pakistan. citsykk@yahoo.com 

Huanglongbing is a serious graft transmissible disease of citrus. Control of this disease is very difficult. Efforts 

are going on to control this disease in Pakistan. Disease control plan includes antibiotic therapy of budwood. 

Tetracycline and penicillin antibiotics were used in this study to clean the budwood from the bacterium 

“Candidatus Liberibacter asiaticus” causing Huanglongbing disease. Tetracycline doses used were 250ppm, 

500ppm, 750ppm, 1000ppm and 1250ppm. Whereas penicillin doses were 25ppm, 50ppm, 75ppm, 100ppm 

and 125ppm. ‘Kinnow’ mandarin (Citrus reticulata) was used as indicator plant. These plants were raised in 

the insect free screenhouse and found Huanglongbing negative before grafting. Budwood was treated with 

different doses of antibiotics and grafted on to the indicator plant. Conventional PCR was performed after 

seven months of grafting by using- 16s rDNA primers OI1/OI2C and rplKAJL-rpoBC operon primers A2/J5 for 

amplification and they show 1160bp and 703bp bands respectively in positive plants. Data regarding the 

treatments showing Huanglongbing negative and Huanglongbing positive results shall be presented. 

S12P19 

Reduction of Huanglongbing in the project of appropriate techniques expansion for the 

cultivation of ‘King’ mandarin (Citrus nobilis) in Southern Vietnam 

Yuasa K.Y. 1 , Nguyen V.H.N. 2 , and Ichinose K.I. 3 

1Japan International Cooperation Agency (JICA), Vietnam office, Vietnam; 2Southern Horticultural Research Institute (SOFRI), Vietnam; 

and 3Japan International Research Center for Agricultural Sciences (JIRCAS), Tropical Agriculture Research Front, Japan. 

Kazuyoshi.Yuasa@gmail.com 

Our project has been performed for expansion of appropriate cultivation techniques of ‘King’ mandarin 

(Citrus nobilis) to growers who have average-sized farms of 1,000 to 10,000m2 in southern Vietnam. In this 

region, most citrus trees are infected by Huanglongbing (HLB) two years after the planting. This paper reports 

the impact of the project on the reduction of HLB infection proportion. The HLB management techniques 

consisted principally of windbreak by ‘Nippa’ palms (Nypa fruticans) or ‘Banana’ (Musa spp.) on all sides of 

orchards, plantings of guavas (Psidium guajava) first and disease-free ‘King’ mandarin trees in one to two 

months later, and insecticide application. Its application was scheduled as 1) soil-drenching of neonicotinoid 

around ‘King’ mandarin trees 10 days before the planting and every two months for one year thereafter; 2) 

leaf- spray was performed every month from the second year on in 11 orchards. In seven of these orchards, 

0.3 - 2.6 % King mandarin trees were infected by HLB in the first year and 3.0 - 21.9 % in the second year. On 

the other hand, the infection proportion in the first year reached at 21.1 - 39.3 % in four orchards where the 

insecticide was not correctly applied. The results indicate that the appropriate use of neonicotinoid evidently 

curtailed the infection of ‘King’ mandarin trees by HLB. The success of our project thus depends on how 

precisely the techniques are transferred and extended to the growers. 


S12P20 

Heat treatment of Huanglongbing –affected citrus trees in field for reduction of “Candidatus 

Liberibacter asiaticus” 

Deng X.L. 1 , Guan L. 1 , Liang M.D. 1 , Xu M.R. 1 , Xia Y.L. 2 , Sequeira R. 3 , and Chen J.C. 4 

1 South China Agricultural University, China; 2 North Carolina State University, USA; 4 USDA-APHIS, USA; and 5 USDA-ARS, USA. 

xldeng@scau.edu.cn 

Huanglongbing (HLB, yellow shoot disease) is a devastating citrus disease worldwide. Research conducted 

by Lin Kung-Hisang et al. in 1960s China suggested that heat treatments were effective at eliminating HLB 

pathogen in scions. We tested the effect of high temperatures on the reduction of “Candidatus Liberibacter 

asiaticus” (Las) titers in HLB-affected citrus trees in Guangdong, China. Heat treatments were delivered 

via covering a tree with a temporary enclosed tent of plastic sheeting, which used natural sunlight to raise 

ambient temperature. Twenty-four sweet orange trees with HLB symptoms in an orchard were selected and 

divided into six blocks with three blocks of four trees, each receiving heat treatments, and the other three 

blocks used as controls. Heat treatments were performed three times in August with temperature exceeding 

38º C for three hours each time. Leaf samples were collected in the following months and real-time PCRs with 

primer set HLBasf/HLBasr and TaqMan probe HLBp were used to monitor Las titer changes. 

S12P21 

Gas exchanged and water relations of ‘Valencia’ oranges trees infected with Huanglongbing (HLB, 

ex greening) 

Saccini V.A.V. 1 , Medina C.L. 2 , Santos D.M.M. 3 , Machado R.S. 4 , and Silva J. 1 

1 Universidade Estadual Paulista - Faculdade de Ciências Agrárias e Veterinárias (UNESP-FCAV), Produção Vegetal, Brazil; 2 Grupo de 

Consultores em Citros (GCONCI), Research, Brazil; 3 Universidade Estadual Paulista - Faculdade de Ciências Agrárias e Veterinárias 

(Unesp-FCAV), Biologia Aplicada a Agropecuária, Brazil; and 4 Conplant - Consultoria, Treinamento, Pesquisa e Desenvolvimento LTDA 

(Conplant), Research, Brazil. clmedina@conplant.com.br 

Symptoms of plants infected with HLB (causal agent “Candidatus Liberibacter “spp.) as part of the leaves 

yellowing and mottling, indicate that their photosynthetic capacity may have changed. Obstructions in 

the phloem, common in the infectious process, may also affect photosynthesis and water relations. In this 

study we verified whether HLB affects gas exchange and water relations in two phases of development of 

symptoms in ‘Valencia’ oranges trees, grafted in Rangpur, with 12 years of age. The treatments consisted 

of (a) leaves of symptomatic patients, (b) leaves of asymptomatic patients (both PCR) and (c) leaves of 

plants PCR -. Evaluations were performed in December 2011 (onset of symptoms) and March 2012 (overt 

symptoms). We investigated the rate of CO2 assimilation (Pn), transpiration (E), stomatal conductance (gs), 

water use efficiency (WUE) and the instantaneous efficiency in the use of CO2 (Pn/Ci) three times (8:00, 

12:00 and 15:00) using a Li-IRGA 6400. The water potential (ψ), measured on a PMS pressure chamber, 

was observed at 6:00 and 14:00 hours. The results showed that Pn and the WUE were not affected, but 

there was a reduction of E, during the hottest hours of the day, probably related to lower gs and ψ. The 

Pn/Ci was somewhat reduced in infected plants, only in March 2012. The maintenance of photosynthetic 

capacity and changes in water balance are possibly related to the obstruction of the phloem and to the 

damage of the plant root system. 

S12P22 

Assessing plant health risk in relation to Xanthomonas citri strains causing citrus bacterial canker 

and evaluating measures for managing this risk 

Holeva M. 1 , Olivier V. 2 , Hostachy B. 2 , Smith J. 3 , MacLeod A. 3 , and Pruvost O. 4 

1 BPI, Department of Phytopathology, Laboratory of Bacteriology, Greece; 2 ANSES, LSV, France; 3 FERA, UK; and 4 CIRAD, UMR PVBMT, 

Réunion, France. olivier.pruvost@cirad.fr 

In the frame of a project funded by the European Food Safety Authority (Prima Phacie), effort was put into 

identifying and testing qualitative plant-pest risk assessment schemes for their suitability in supporting risk 

management decisions for the European Union. Five schemes were tested, two largely based on the EPPO 


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scheme and three adapted from schemes used in non-European countries. We report the results from the 

application of these schemes as applied to Xanthomonas citri strains causing Citrus Bacterial Canker, in 

regard to the risk of its entry, establishment and spread, as well as its potential impact. For this pathogen, 

three entry pathways into the EU risk assessment area were considered: a) import of fresh citrus fruits, b) 

import of ornamental rutaceous plants or plant parts, and c) illegal entry of plant propagative material. With 

the current EU measures in place, of the five schemes tested, two indicated path (c) as that of the highest 

risk, whereas the other three suggested path (a) as such. This discrepancy is due to the different level of 

details the components of the risk of entry are considered in each scheme. Most schemes suggested that 

the establishment potential lay around the mid-range of possible values. All schemes indicated a high rate 

for potential spread (primarily through human activities) and a medium to high rate for impact potential. 

The effectiveness of risk management measures was evaluated by comparing results of assessments with 

and without management measures in place. 

S12P23 

Characterization of a new Xanthomonas citri subsp. citri isolate which triggers a host-specific response 

Roeschlin R.A. 1 , Chiesa M.A. 1 , Enrique R. 2 , Favaro M.A. 1 , Torres P.S. 3 , Filippone M.P. 2 , Gmitter Jr. F.G. 4 , Vojnov A.A. 3 , 

Castagnaro A.P. 2 , Marano M.R. 1 , and Gadea J. 5 

1 Instituto de Biología Molecular de Rosario-CONICET (IBR), Argentina; 2 Estación Experimental Obispo Colombres (EEAOC-Tucuman), 

Argentina; 3 Fundación Pablo Cassará-Buenos Aires, Argentina; 4 University of Florida (IFAS), Citrus Research and Education Center Lake 

Alfred, U.S.A.; and 5 Instituto de Biología Molecular y Celular de Plantas (IBMCP), Spain. jgadeav@ibmcp.upv.es 

Citrus is an economically important fruit crop that is severely afflicted by Asiatic Citrus Bacterial Canker (CBC), 

a disease caused by Xanthomonas citri subsp. citri (XC). Recently, we have identified a XC strain, named XCT44, 

which induces a hypersensitive-like response in Citrus limon leaves. To gain insight into the dynamics of these 

host-specific responses, we have investigated biofilm formation and accumulation of defense markers by 

XCT44 on different citrus species. Biofilm formation was monitored by confocal laser scanning microscopy 

(CLSM) over a 10-day period. XCT44 strain was unable to form structured biofilm after 6 days post-inoculation. 

This observation is associated with early production of reactive oxygen species by the plant. Transcriptomic 

analysis of C. limon leaves in response to the non pathogenic (XCT44) and pathogenic (XC) strains showed 

that XCT44 induces specific genes that points towards the involvement of salicylic acid and glucosinolates 

metabolism in the onset of the defense responses. Further characterization of these genes with a role in this 

HR-like response will be important for the development of new strategies to manage the disease. 

S12P24 

Analysis of genetic diversity of Xanthomonas citri subsp citri strains. Characterization of a new 

isolate which triggers a host-specific response 

Siciliano M.F. 1 , Chiesa M.A. 1 , Ornella L. 2 , Pino Delgado N. 1 , Favaro M.A. 1 , Sendín L.N. 3 , Roeschlin R.A. 1 , Orce I.G. 3 , Ploper 

L.D. 3 , Vojnov A.A. 4 , Filippone M.P. 3 , Castagnaro A.P. 3 , and Marano M.R. 1 

1 Instituto de Biologia Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Cientificas y Tecnologicas, Universidad 

Nacional de Rosario, Facultad de Ciencias Bioquímicas y Farmacéuticas, (IBR), Area Virologia, Argentina; 2 Centro Internacional Franco 

Argentino de Ciencias de la Información y de Sistemas (CIFACIS), Argentina; 3 Estación Experimental Agroindustrial Obispo Colombres 

(EEAOC), Sección Biotecnología, Argentina; and 4 Instituto de Ciencia y Tecnologia Dr. Cesar Milstein, Fundacion Pablo Cassara- 

CONICET, Argentina. fragarina@yahoo.com.ar 

Citrus is an economically important fruit crop that is severely afflicted by Asiatic Citrus Bacterial Canker 

(CBC), a disease caused by Xanthomonas citri subsp. citri (XC). Argentina is one of the world´s largest citrus 

producers, accounting for 17% of global lemon supply, with the majority of production concentrated in the 

northwestern province of Tucuman. To gain insight into the genetic diversity of Xanthomonas causing CBC in 

Tucuman, a total of 42 Xanthomonas isolates were collected from different citrus species across seventeen 

different orchards and subjected to molecular, biochemical and pathogenical tests. Analysis of genomespecific 

XC markers and DNA polymorphism based on rep-PCRs showed that all isolates belonged to XC. 

Thirty-eight haplotypes with relatively high genomic inter-relationship compared to XC reference strains 

were discriminated. Pathogenicity tests showed that one isolate, named XCT44, which shares 91% genetic 

similarity to the reference strain XCT, has specific host range. XCT44, induces a hypersensitive-like response 

in Citrus limon and Citrus paradisi leaves and weak canker lesions in Citrus aurantifolia and Citrus clementina 


leaves. Although XCT44 produces less exopolysaccharides than the reference strain XCT, this deficiency is 

not involved in the phenotype observed in C. limon leaves. This study constitutes the first report on the 

characterization of XC in the northwest of Argentina. 

S12P25 

The causal agent of Citrus Canker, Xanthomonas citri subsp. citri, enters in a reversible viable but 

non culturable state induced by copper, that can be reverted by citrus leaf extract 

Golmohammadi M. 1 , Llop P. 2 , Cubero J. 3 , and López M.M. 2 

1 Iran Citrus Research Institute (ICRI), Dept. Plant Protection, Iran; 2 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro 

de Protección Vegetal y Biotecnología, Spain; and 3 Instituto Nacional de Investigación y Tecnología Agraria (INIA), Dpto. Protección 

Vegetal, Spain. mlopez@ivia.es 

Xanthomonas citri subsp. citri (Xcc) is a quarantine organism in the European Union, that causes Citrus Canker, 

a severe bacterial disease that affects most commercial citrus species, but not present in the Mediterranean 

countries. Copper compounds are widely used in the integrated management of this disease and have been 

described as inducers of the viable but non culturable state (VBNC) in several plant pathogenic bacteria, 

including Xcc. VBNC may be considered as a state previous to bacterial death or a survival strategy adopted 

by bacteria in adverse conditions. To demonstrate the biological significance of VBNC in Xcc, experiments have 

been performed in order to clarify two essential characteristics to consider this state as a survival strategy: 

reversibility and durability. Entrance of Xcc into the VBNC state has been observed in low nutrient medium, or in 

presence of copper at concentrations employed in field treatments and persistence of Xcc in VBNC condition has 

been demonstrated until five months under copper exposure. Reversibility was demonstrated after addition of 

culture media, or citrus leaf extract, both acting as chelating agents of copper ions. Culturability was evaluated by 

colony counting and viability by membrane integrity, a respiratory test and a real-time RT-PCR system targeting 

mRNA from gumD gene. This report demonstrates that this state is a reversible long term survival strategy that 

may occur in the field after copper treatments, giving false negative results when checking for their efficiency. 

S12P26 

Effect of N-acetyl-L-cysteine (NAC) on the epiphytic fitness of Xanthomonas citri subsp. citri (Xcc) 

in sweet orange 

Picchi S.C., Inui-Kishi R.N., Takita M.A., Machado M.A., and de Souza A.A. 

Centro APTA Citros Sylvio Moreira (IAC), Laboratório de Biotecnologia, Brazil. rosangela@centrodecitricultura.br 

The leaf surface harbors bacterial epiphytes that are capable of influencing the cell-to-cell signaling system of 

the plant pathogen Xcc, causal agent of Citrus Canker. Here, we have evaluated the role of bacterial attachment 

and biofilm formation in leaf colonization during canker development on a susceptible variety of sweet orange. 

NAC is a mucolytic agent that has anti-bacterial properties and also decreases biofilm formation by a variety 

of bacteria, and copper-based products are routinely used as a standard control measure for Citrus Canker. 

We investigated if it is possible to use NAC as an antimicrobial compound together with copper and the effect 

of the NAC on the epiphytic fitness of bacteria. The Xcc GFP-labeled bacteria were inoculated by spraying on 

the surface of sweet orange leaves. The bacterial cell multiplication and diffusion processes were observed 

directly under fluorescence microscope at different intervals after inoculation. The results showed that NAC 

had a detachment effect and that the leaves that sheets copper application, showed reduced lesions. CFU/mL 

from leaves were counted, showing a reduction in Xcc concentration. 

S12P27 

Disruption of ParB alters the virulence of Xanthomonas citri subsp. citri 

Ucci A.P.U., and Ferreira H.F. 

1 Universidade Estadual Paulista (UNESP), Biological Sciences, Brazil. mandapiovesan@gmail.com 

The Gram-negative bacterium Xanthomonas citri subsp. citri (Xcc) is the etiological agent of Citrus Canker, a 

severe disease that affects all species and cultivars of citrus worldwide. Since there is not an effective control 


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for this disease, we started the characterization of some essential biological processes of Xcc, among them 

chromosome segregation, in an attempt to identify targets to which we could develop antimicrobials. Here, 

we describe the effects of ParB disruption in Xcc, a well conserved factor in bacteria that has no homologues 

in derived eukaryotes. ParB, together with its partner ParA, is responsible in several other organisms for 

the proper segregation of the genetic material. Using phase contrast microscopy we show that Xcc mutants 

disrupted for parB (Xcc parB::pAPU2) form filaments, which is consistent with a chromosome segregation/ 

cell division defect. Surprisingly, we found that these cells also lost the ability to colonize the susceptible host 

Rangpur lime. ParB has been implicated with bacterial motility and divisional septum placement; however, 

our results are the first to report on the involvement of the chromosome segregation protein ParB with 

virulence. 

S12P28 

Analysis of microRNAs involved in defense response signaling against Xanthomonas spp. in Citrus limon 

Chiesa M.A. 1 , Torres P.S. 2 , Campos L. 3 , Roeschlin R.A. 1 , Gerhardt N. 1 , Filippone M.P. 4 , Conejero V. 3 , Castagnaro A.P. 4 , 

Vojnov A.A. 2 , Gmitter Jr. F.G. 5 , Gadea J. 3 , and Marano M.R. 1 

1Instituto de Biologia Molecular de Rosario-CONICET (IBR), Argentina; 2Fundación Pablo Cassará-Buenos Aires, Argentina; 3Instituto de Biologia Molecular y Celular de Plantas (IBMCP), Universidad Politecnica de Valencia-CSIC, Spain; 4Estacion Experimental Obispo 

Colombres (EEAOC-Tucuman), Argentina; and 5University of Florida (IFAS), Citrus Research and Education Center Lake Alfred, U.S.A.. 

jgadeav@ibmcp.upv.es 

MicroRNAs (miRNAs) are small conserved noncoding RNAs of ~ 22 nt long that are present in most eukaryotic 

genomes. They play a fundamental role as negative regulators of target genes, which are involved in different 

signaling pathways of biological processes, such as development, hormone signaling and response to 

biotic and abiotic stresses. Citrus spp. is severely afflicted by Asiatic Citrus Bacterial Canker (CBC), a disease 

caused by Xanthomonas citri subsp. citri (XC). To get insight into the plant defense responses that could 

ameliorate canker development, we studied C. limon miRNAs expression in the interaction with a highly 

virulent strain (XC), a non-pathogen strain of citrus (X. campestris pv. campestris, Xcc) and a strain that 

generates a hypersensitive response (X. fuscans pv aurantiifoli strain C, Xfa-C). The obtained results revealed 

interesting expression patterns for some of the miRNAs involved in hormone signaling pathways (miR159, 

miR160, miR167, miR393), oxidative stress (miR398) and cell-wall strengthening (miR408). These miRNAs 

are presumably regulating target genes involved in signalling pathways important for C. limon resistance. The 

biological significance of the differential expression of the assayed miRNAs in compatible, incompatible and 

non-pathogenic interactions is discussed. 

S12P29 

Influence of different copper hydroxide spray volumes and doses to control Citrus Canker in 

lemon in Tucumán, Argentina 

Salas López H. 1 , Mansilla C. 2 , Stein B. 1 , Rojas A. 1 , and Figueroa D. 1 

1Estación Experimental Obispo Colombres (EEAOC), Fruticultura, Argentina; and 2CITRUSVIL, Argentina. hsalas@eeaoc.org.ar 

Citrus Canker caused by Xanthomonas citri subsp. citri is one of the most important citrus diseases. Three 

volumes (high, medium and low: 10000, 5000 and 2000l/ha, respectively) and two doses (15 and 7.5 Kg/ha of 

commercial product) of copper hydroxide (53.8%) bactericides were evaluated in lemons. A trial was conducted 

throughout three consecutive crop seasons in a commercial grove (Limoneira 8 A Lisbon/Swingle citrumelo) 

planted with 250 trees/ha density in 1997. A randomized complete block design with four replicates and six 

treatments was considered: 1) high volume-high dose (traditionally used); 2) medium volume-high dose; 3) 

low volume-high dose; 4) medium volume-low dose; 5) low volume-low dose and 6) untreated. Monthly sprays 

from October to January were performed in each season and canker incidence on fruit was estimated at harvest. 

Regardless of the volume and dose, copper significantly decreased canker incidence on fruit with a considerable 

decrease as the year elapsed. The highest incidence was recorded in untreated trees (91% of infested fruit) and 

the lowest (7%) in copper-treated trees. Differences among treatments were not significant in years with low 


incidence of canker. Only in the year with 91% of incidence in untreated trees, a high dose of copper sprayed 

in medium and low volumes significantly increased canker control, compared to the traditional high volume 

treatment. The latter was in turn more effective than low dose sprayed in medium and low volumes. 

S12P30 

Control of Citrus Canker(Xanthomonas citri subsp. citri) mediated by neonicotinoids in 

combination with acibenzolar-S-methyl and copper 

Barreto T.P. 1 , Pozzan M. 2 , and Leite R. 1 

1Instituto Agronomico do Parana (IAPAR), Area de Proteção de Plantas, Brazil; and 2Syngenta Proteção de Cultivares Ltda. (Syngenta), 

Proteção de Cultivos, Brazil. ruileite@iapar.br 

Asiatic Citrus Canker, caused by Xanthomonas citri subsp. citri, is a serious disease for commercial citrus 

production. Multiple sprays of copper-based bactericides during the growth season are standard measure for 

Citrus Canker control worldwide. Disadvantages for long-term use of copper bactericides include the selection 

for copper resistance in Xanthomonas populations and accumulation of copper in the soil. Systemic acquires 

resistance (SAR) is an innate plant defense that may confer long-lasting protection against a broad spectrum 

of microorganisms. SAR may be activated by treatment of plants with chemical inducers. The purpose of this 

research was to evaluate the efficacy of applications of SARs neonicotinoids in combination with acibenzolar- 

S-methyl and copper oxychloride (COC) to control Citrus Canker. Plants of sweet orange ‘Pera’ (Citrus sinensis) 

were treated by drench with neonicotinoid insecticides imidacloprid (IMI) and thiamethoxam (TMX), and 

acibenzolar-S-methyl (ASM), and by foliar applications of ASM and COC. ASM and COC were applied during 

the entire growth season, in a six-spray program. IMI and TMX were applied in the first and third sprays of 

the six-spray program in an attempt to reduce early canker disease on foliage. ASM or TMX in combination 

with COC were the most effective treatments to reduce Citrus Canker incidence on foliage as compared to the 

untreated plants, COC alone and the other SARs treatments. 

S12P31 

Activity of antimicrobial peptides (AMPs) against Xanthomonas citri subsp. citri (Xcc) in Citrus 

sinensis var. ´Baía´ 

Inui-Kishi R.N. 1 , Freitas-Astua J. 2 , Picchi S.C. 1 , Brand G.D. 3 , Bloch JR C. 3 , Falcao A.O. 4 , Stach-Machado D. 4 , Cilli E.M. 5 , 

and Machado M.A. 1 

1Centro APTA Citros Sylvio Moreira (IAC), Laboratorio de Biotecnologia, Brazil; 2Embrapa Cassava and Fruits (EMBRAPA), Cruz das 

Almas, Brazil; 3EMBRAPA CENARGEM (EMBRAPA), Brazil; 4Universidade Estadual De Campinas (UNICAMP), Biologia, Brazil; and 

5Universidade Estadual Paulista Julio De Mesquita Filho (UNESP-ARARAQUARA), Departamento de Bioquimica e Tecnologia Quimica, 

Brazil. rosangela@centrodecitricultura.br 

The control of plant pathogens such as Xcc requires continuous use of chemicals, favoring the selection of 

resistant isolates and increasing the risk of contamination to different organisms and environment. Thus, 

it becomes important to search for feasible alternatives as AMPs. The aim of this study was to evaluate 

the activity of six potential AMPs found within the citrus genome, as well as in other organisms, in the 

control of Xcc. The in vitro growth inhibition of Xcc by the peptides was determined by MIC and MBC. 

The pC1 obtained from citrus efficiently controlled Xcc at 64 µg mL-1, while the MIC values for peptides 

pH2, pH3 and pH4 were 16, 4 and 8 µg mL-1 respectively. Experiments using detached C. sinensis leaves 

were conducted with the same conditions used for the in vitro tests. For these experiments, a strain of Xcc 

marked with GFP was used. The fluorescence obtained by GFP allowed monitoring the development of the 

bacteria within the leaves. To confirm if it is able to control bacteria growth, CFU/mL from lesion leaf was 

determined. The inhibition of Xcc growth was observed by five of the six peptides evaluated. Hemolysis 

activity from the selected peptides was determined as the main measurement of peptide toxicity toward 

higher eukaryotic cells. pC1 showed low percentage of hemolysis, while pH1, pH3 and pH4 exhibited higher 

hemolysis levels. Five of the peptides tested show clear effect on Xcc, and the pC1 obtained from citrus 

could be an interesting candidate. 


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S12 

S12P32 

Bacteriostatic and bactericidal activity of different essential oils to alternative control in vitro of 

Xanthomonas citri subsp. citri 

Sauer A.V. 1 , Santos E.M. 1 , Zuliani-Gonçalves A.M.O. 1 , Nocchi P.T.R. 1 , Nunes W.M.C. 1 , and Bonato C.M. 2 

1 Universidade Estadual de Maringá (UEM), Núcleo de Pesquisa em Biotecnologia Aplicada (NBA), Centro de Ciências Agrárias (CCA), 

Brazil; and 2 Universidade Estadual de Maringá (UEM), Centro de Ciências Agrárias (CCA), Brazil. alinevanessasauer@hotmail.com 

Xanthomonas citri subsp. citri is the causal agent of Citrus Canker, which is easily disseminated and 

there has been no effective control until now. Excessive use of pesticides causes problems of human and 

environmental contamination, and the selection of resistant pathogens. Thus, the study of alternative 

control methods with a bactericidal action is critical to mitigate the adverse effects mentioned above. 

The evaluation of the chemical components of essential oils indicated that some of these may change 

their activity and have bactericidal action. The aim of this study was to evaluate the Minimum Inhibitory 

Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of essential oils of Citrus aurantium, 

Cymbopogon winterianus, Foeniculum vulgare, Pinus elliottii and Ocimum gratissimum. The method of 

micro dilution plate was used to evaluate the MIC. Subsequently, an aliquot of 5μl (from the incubation 

used for determination of MIC) was used to analyze the MBC, using Petri plates containing Nutrient Agar 

(NA), as a growing medium. The results showed bactericidal activity of the essential oils, however C. 

winterianus had the lowest concentration among the oils tested (MIC = 0.007 µl/ml and MBC = 0.487 µl/ 

ml). With the result of the MIC (0.007 µl/ml) C. winterianus is considered bacteriostatic, and only from 

0.487 µl/ml it would be bactericidal. 

S12P33 

Canker control by the siderophore pyochelin from Pseudomonas fluorescens 

Adler C. 1 , Lami M.J. 1 , de Cristobal R.E. 1 , Filippone M.P. 2 , Castagnaro A.P. 2 , and Vincent P.A. 1 

1 Instituto Superior de Investigaciones Biológicas (INSIBIO), Argentina; and 2 Estación Experimental Agroindustrial Obispo Colombres 

(EEAOC), Biotecnología, Argentina. conadler@uolsinectis.com.ar 

This work shows the identification of a compound able to inhibit Xanthomonas citri pv. citri growth in vitro and 

in vivo. Firstly, we isolated from environmental samples, bacteria able to inhibit X. citri pv. citri (Citrus Canker 

agent) in vitro. Among the selected isolates, we focused in one showing a remarkable activity. The strain 

was characterized as Pseudomonas fluorescens after sequencing its 16S rDNA and analyzing the sequence 

with BLASTn. Purification and chemical analysis of the active compound allowed us to assign the inhibitory 

activity to pyochelin (Pch). Since this molecule is a siderophore, we wondered if the inhibition observed was 

a result of iron scavenging. Surprisingly, when we supplemented media with an excess of iron, we observed 

practically no change in the inhibition activity. In an attempt to identify the action mechanism of pyochelin, 

we evaluated the ability of pyochelin to generate reactive oxygen species (ROS) within a culture of X. citri pv. 

citri and its correlation with the inhibitory activity. In fact, we observed increased ROS levels when Pch was 

added. In addition, the reducer agent ascorbic acid, lowered ROS levels and the antibiotic activity implying 

that inhibition is probably caused by oxidative stress. Finally, we studied the use of Pch in a model of canker 

disease. Pch showed to reduce canker formation on leaves of ‘Eureka’ and ‘Lisbon’ variety plants. These 

results show Pch as a promising compound for Citrus Canker biocontrol. 

S12P34 

Genetic response of sweet orange treated with chitosan to the infection of Xylella fastidiosa 

Coqueiro D.S.O. 1 , Rodrigues C.M. 2 , Souza A.A. 2 , Takita M.A. 2 , Kishi L.T. 2 , and Machado M.A. 2 

1 Universidade Federal da Bahia (UFBA), Biochemistry, Brazil; and 2 Centro de Citricultura Sylvio Moreira, Instituto Agronômico (IAC), 

Laboratory of Biotechnology, Brazil. marcos@centrodecitricultura.br 

One alternative that has been widely studied of disease control is the use of chitosan. This study aimed 

to generate and evaluate the transcriptome of sweet orange (Citrus sinensis) plants treated with chitosan, 

challenged or not with Xylella fastidiosa (Xf). Seven months old sweet orange plants grafted on ‘Rangpur’ 


lime were treated with chitosan (CHI) 4 mg.mL-1 in HCl 0.05 N pH 5.6. After 24 h, plants were artificially 

inoculated with suspension of Xf 9a5c strain (108 cells.mL-1) in PBS buffer or PBS buffer only. The total RNA of 

four replicates per treatment (CHI Xf, HCl Xf, CHI PBS and HCl PBS) was extracted and mixed forming a pool of 

RNAs which were sequenced in Illumina platform. After sequencing, the transcripts quantitation was used to 

calculate the level of differential expression between treatments and control (HCl PBS) and their significance 

in Cuffdiff software. We obtained 640 differentially expressed transcripts to CHI treatment, 1232 to CHI Xf and 

1075 to HCl Xf. For genes of plant defense we found predominantly repression of genes of auxin pathway. For 

the induced genes, CHI treatment showed predominance of genes of flavonoid pathway and hypersensitivity 

response, for the CHI Xf were observed predominance of genes of ethylene and jasmonate pathway and for 

the HCl Xf genes of salicylic acid pathway, ethylene and jasmonate pathway were observed. Therefore, we 

suggest that chitosan induce jasmonate and ethylene-dependent defense-signaling pathway in sweet orange. 

Support: INCT Citros (FAPESP and CNPq) 

S12P35 

Genetic variation of California Spiroplasma citri populations revealed by two genetic loci 

Wang X. 1 , Doddapaneni H. 2 , Chen J.C. 1 , and Yokomi R.K. 1 

1 USDA Agricultural Research Service, San Joaquin Valley Agricutural Sciences Center (USDA ARS SJVASC), Crop Diseases, Pests and 

Genetics, USA; and 2 Baylor College of Medicine (BCM), Human Genome Sequencing Center, USA. ray.yokomi@ars.usda.gov 

Citrus Stubborn Disease (CSD), known to be present in California since 1915, was confirmed to be caused 

by Spiroplasma citri in 1972. Hosts of S. citri include citrus and a wide range of annual weeds, ornamentals 

and crops such as carrots and sesame. Genetic variation of S. citri in California was examined previously by 

RAPD-PCR with 20 primer pairs but no unique genetic signatures were found. Using partial chromosome 

and plasmid sequences of S. citri recently released in GenBank, a conserved hypothetic peptidyl-arginine 

deiminase protein (PADP) and a transmembrane protein (TMP) of plectrovirus spv1-r8a2b were selected in 

silico to evaluate genetic diversity of S. citri from different hosts and locations. Two specific PCR primer sets 

designed proved to be effective. The first was PADPf/PADPr which targeted a region with variable tandem 

repeat numbers (TRNs); the second was TMPf/TMPr which had multiple priming sites in the published 

genome of S. citri strain GII3-3X. A panel of 31 strains of S. citri from California, Illinois and the Mediterranean 

region was evaluated using the two primer sets by PCR. Electrophoretic profiles of PCR amplicons from 

the strains tested consistently showed three TRN patterns in the PADP locus and three in the TMP locus. 

Interestingly, strains which showed a different profile for PADP also showed a different profile for TMP and 

each pattern group constituted a set. Sequence analyses were conducted amongst strains in each pattern 

group and revealed at least three genotypes present in Californian S. citri populations. Further study of 

field strains from different geographical origins using the two loci described should provide insight on the 

biology and epidemiology of S. citri. 

S12P36 

Serological detection of Spiroplasma citri using a bacterial secreted protein as the detection 

marker 

Shi J.S., Pagliaccia P.D., Morgan M.R., Ma W.M., and Vidalakis G. 

University of California, Riverside (UCR), Plant Pathology and Microbiology, U.S.A. vidalg@ucr.edu 

Citrus worldwide is facing major threats from insect-transmitted and phloem-limited bacterial diseases such 

as Huanglongbing (HLB, “Candidatus Liberibacter” spp.) and Stubborn (CSD, Spiroplasma citri). Management 

of such diseases is difficult, expensive, heavily based on tree eradication and insecticide treatments for vector 

control. The success of any disease management program is based on early pathogen detection. The most 

commonly used diagnostic or survey methods are PCR based and require the presence of bacterial cells or 

DNA in the tested sample for positive diagnosis. This can be problematic in the case of citrus since only a few 

leaves or stems from a whole tree and eventually a few mg of tissue are processed for DNA extraction while 

the titer and distribution of the pathogen within trees, types of tissue and disease progression are variable. 


S12

S12 

Here, we report a novel diagnostic method for CSD using a secreted protein of S. citri as the detection marker. 

Because S. citri resides in the phloem, secreted proteins could disperse through the plant transportation 

system, thereby facilitating detection. We identified S. citri proteins that are secreted in high levels in the 

presence of phloem extract by mass spectrometry. We then generated antibodies against one of these proteins 

(ScCCPP1) and used it in direct tissue imprint detection assays. Remarkably, ScCCPP1 antibody robustly 

detected S. citri-infected trees, in a manner that at certain cases was even more reliable than quantitative 

PCR. Furthermore, using an experimental protocol for mechanical inoculation of S. citri, we successfully traced 

S. citri during infection development using both PCR- and ScCCPP1 antibody-based methods. In conclusion, 

ScCCPP1 antibody holds the promise of developing robust immunoassay-based diagnostic methods for CSD. 

More importantly, the novel strategy of using secreted proteins as detection markers can be adapted for the 

diagnosis of ecologically similar diseases, such as HLB. 

S12P37 

Witches’ Broom Disease of Lime, a serious disease of acid lime (Citrus aurantifolia) in the 

Arabian Peninsula, and viral-like diseases of citrus in Oman 

Al-Sadi A.M., AL-Yahyai R.A., and Al-Said F.A. 

Sultan Qaboos University (SQU), Crop Sciences, Oman. alsadi@squ.edu.om 

Acid lime (Citrus aurantifolia) is among the top four fruit trees in terms of production and area of cultivation in 

Oman. In the 1970s, disease symptoms were observed on lime trees in the northern part of the country. The 

symptoms were characterized by clustering of leaves, which become small in size and light green to yellow 

in color. Affected trees are usually killed within 5 years after appearance of symptoms. The disease, which 

was called Witches’ Broom Disease of Lime (WBDL), is caused by “Candidatus Phytoplasma aurantifolia”. It 

spread to other areas of the country and was reported in the UAE in 1989, in Iran in 1997, in India in 1999 

and in Saudi Arabia in 2009. Loss of area cultivated with lime trees in Oman is currently 50% of that in 1990 

and the disease wiped out over half a million lime trees in the country. Population genetic analysis of acid 

limes in Oman provided evidence that the low level of genetic diversity of acid lime in Oman and frequent 

movement of acid lime planting material across districts are two main factors which contributed to the spread 

of the disease and high susceptibility of acid limes to WBDL. A survey in 2009 and 2010 of 20,000 lime trees 

in Oman showed that the disease is present in all regions and farms, with only 2 asymptomatic lime trees 

which are 25-45 years old. Although the two lime trees may appear to have tolerance or resistance to WBDL, 

studies are in progress to investigate factors suppressing disease symptoms in these trees. Empirical data 

provided evidence for a synergistic effect between phytoplasma and some viral pathogens (e.g. tristeza) in 

the decline of acid limes, a hypothesis which is currently under investigation. Other areas of research on 

WBDL include genetic diversity of the phytoplasma, physiological aspects of the phytoplasma-affected limes 

and management options. 

S12P38 

Portable chemical sensors for monitoring infection-specific volatiles in asymptomatic citrus 

Fink R.L. 1 , Aksenov A.A. 2 , Thuesen L.H. 1 , Pasamontes A. 2 , Cheung W.H.K. 2 , Peirano D.J. 2 , and Davis C.E. 2 

1Applied Nanotech Inc. (ANI), USA; and 2University of California, Davis (UC Davis), Mechanical and Aerospace Engineering, USA. 

dfink@appliednanotech.net 

Volatile organic compounds (VOCs) are emitted from all plants, and there is mounting evidence these VOCs 

reflect internal health status and change in response to pathogen infection and other cues. Our group has 

developed a portable chemical sensing platform that can monitor for VOC emission changes that result 

from citrus bacterial and viral infections. To date, our VOC library includes putative signal fingerprints for 

Huanglongbing (HLB), Citrus Tristeza Virus (CTV) and Citrus Variegated Chlorosis (CVC). Our mobile platform 

is robust and capable of operating in field conditions. We have also developed customized data analysis 

methods to compare data from unknown samples to our database, and to determine the probability of 

infection for a newly sampled tree. 


S12P39 

Unforbidden fruits: Preventing citrus smuggling by introducing varieties culturally significant to 

ethnic communities 

Karp D. 1 , Siebert T. 1 , Vidalakis G. 2 , Krueger R.R. 3 , Lee R.F. 3 , and Kahn T. 1 

1University of California, Riverside, Department of Botany and Plant Sciences, United States; 2University of California, Riverside, 

Department of Plant Pathology and Microbiology, United States; and 3United States Department of Agriculture, National Clonal 

Germplasm Repository for Citrus and Dates, United States. dkarp@ucr.edu 

Fruits and vegetative materials of citrus and citrus relatives are commonly smuggled into California, 

presenting a risk of introducing Huanglongbing (“Candidatus Liberibacter” spp.) and its insect vector, 

Asian Citrus Psyllid (Diaphorina citri), as well as other exotic citrus diseases and pests. Certain species and 

cultivars such as curry leaf (Bergera koenigii), bael (Aegle marmelos) and Etrog citrons (Citrus medica) 

are in demand from ethnic and religious communities, but supplies are limited because of quarantine 

restrictions. Orchards, nursery trees, and disease-tested propagating materials necessary for their 

production have not been available. The Unforbidden Fruits project aims to complement interdiction by 

making pathogen-tested sources of these trees and leaves available in California. The project has collected 

relevant germplasm, tested it for seed-transmissible diseases, and distributed seeds to California nurseries. 

Before starting seed distribution, it was necessary to modify state and federal regulations that required 

that all mother and increase plants in approved insect-resistant structures be derived from material that 

has undergone shoot-tip grafting or therotherapy, which is impractical for citrus relatives such as curry 

leaf and bael, for which no such protocols exist. Other citrus and citrus relatives of quarantine significance 

include wampee (Clausena lansium), satkara (C. macroptera var. assamensis), and Asian cultivars of 

pummelo (C. maxima). 

S12P40 

Introduction of control on main citrus diseases in P. R. China 

Zhou C.Y. 

Citrus Research Institute of Chinese Academy of Agricultural Sciences (CRIC), China. changyong@hotmail.com 

Since 2001 ca. 100 modern virus-free citrus nurseries have been established in 13 provinces of China, 

which have the capacity of producing ca. 114 million nursery trees per year. Through practicing the virusfree 

propagation scheme, the losses caused by the graft-transmissible citrus diseases in inland area have 

been dramatically reduced. Severe stem-pitting tristeza is still a threat to susceptible sweet oranges and 

pummelos, a few mild isolates with potential protective capability screened from thousands of field isolates 

have been being applied in field experiments for mild strain cross protection. In order to control quarantine 

diseases and pests, Chongqing Citrus Quarantine Pest-free Zone has been being practically set up since 

2007, as well as many efforts on setting up early warning system for citrus quarantine pathogens and 

pests have been made in Chongqing. However, Huanglongbing (HLB) is still the main threat to the coastal 

citrus areas, with high potential threat to those boundaries due to the northward movement of citrus 

psyllids. In recent years, the control of HLB is forcefully organized by the plant protection stations of the 

provincial governments. Three measures including strictly controlling the psyllid, removing diseased trees 

promptly and planting HLB-free nursery trees are still recommended. Guangxi province is an example of 

the successful control of HLB in the past few years, where the percentage of HLB has dropped down to now 

less than 1% from over 10%, whereas much attention has not been paid in other coastal area. The control 

of fungi diseases is focusing on Anthracnose, Brown Spot (Alternaria alternata), Black Spot (Phyllosticta 

citricarpa) and Fruit Rot. This poster will also introduce the progress on virus-free scheme, construction 

of quarantine pest-free zone, and a few state projects for public interest on controlling HLB, Citrus Canker, 

virus diseases of fruit trees and fruit rot. 


S12

S12 

S12P41 

Gaining experience with exotic citrus pest and disease threats to Australia through collaborative 

work in Bhutan 

Sanderson G. 1 , Hardy S. 2 , Donovan N. 3 , Beattie A. 4 , Holford P. 4 , Dorjee D. 5 , Wangdi P. 5 , Thinlay T. 6 , and Om N. 6 

1Dareton Primary Industries Institute (DPII), NSW Department of Primary Industries, Australia; 2University of Newcastle, Ourimbah 

Campus (UN), NSW Department of Primary Industries, Australia; 3Elizabeth Macarthur Agricultural Institute (EMAI), NSW Department 

of Primary Industries, Australia; 4University of Western Sydney (UWS), School of Science and Health, Australia; 5Horticulture Division 

(DoA), Department of Agriculture, Bhutan; and 6National Plant Protection Centre (NPPC), Department of Agriculture, Bhutan. 

graeme.sanderson@dpi.nsw.gov.au 

The Australian Centre for International Agricultural Research (ACIAR) commissioned the NSW Department 

of Primary Industries (NSW DPI) to undertake a project to help improve mandarin production in Bhutan. An 

important aspect of the project has been research on pests and diseases that are exotic to Australia, including 

Huanglongbing (HLB), its vector the Asiatic Citrus Psyllid (ACP), Chinese Citrus Fruit Fly and Citrus Powdery 

Mildew. HLB and its vectors pose one of the greatest risks to Australia’s citrus and nursery industries. HLB 

and ACP are not present in Australia, but occur in nearby Indonesia, East Timor and New Guinea. Movement 

of the pathogen and the psyllid eastward from Asia to Australia through cyclonic winds or illegal movement 

of infected plant material is highly likely. Chinese citrus fruit fly is a major pest of citrus in South-west China 

and North east India and Bhutan. In Bhutan, the fly infests mandarin fruits causing premature ripening and 

subsequent fruit drop. Yield losses due to this fly can go up to 80% in severely affected orchards. Citrus 

powdery mildew is a common problem in Asian citrus orchards, leading to premature leaf and fruit drop and 

twig dieback. It is particularly prevalent in nursery plantings, shady orchards and poorly ventilated orchards 

and can be a significant problem in recently pruned trees infecting all the new re-growth. Powdery mildew 

reduces tree productivity, fruit yield and quality. It is important that Australia has personnel with expertise in 

the identification of these exotic pests and diseases. Our main defense against these threats is through the 

maintenance of strict quarantine protocols and routine monitoring and surveillance programs. Working in 

Bhutan provides the Australian citrus and nursery industries with increased capabilities for the development 

of exotic pest and disease surveillance programs, contingency plans and the ability to quickly react to an 

incursion. 

S12P42 

Nucleotide sequence analysis of ribosomal protein gene sub-units (rplA-rplJ) of “Candidatus 

Liberibacter asiaticus” infecting different citrus cultivars in Maharastra, India 

Ghosh D.K. 1 , Bhose Sumit1 , and Gowda S. 2 

1Plant Virology Laboratory, National Research Center for Citrus, India; and 2Citrus Research and Education Center, University of 

Florida, USA. ghoshdk@hotmail.com 

Citrus greening disease (Huanglongbing, HLB) is one of the most serious and destructive citrus disease known 

in the world. The causative agent, “Candidatus Liberibacter asiaticus”, a Gram negative alpha Proteobacterium 

associated with in the sieve tube elements of the phloem tissue of infected plants has not been cultured so 

far. The disease is transmitted by grafting and vectored by the insect, citrus psylla Diaporina citri. During 

a recent survey conducted in 2010 in Western Maharashtra of India, disease occurrence was recorded in 

different citrus cultivars viz. sweet orange cultivar ‘Mosambi’, ‘Rangpur’ lime, ‘Nagpur’ mandarin, acid lime 

and rough lemon. Maximum disease incidence up to 41.5% was observed in sweet orange cultivar ‘Mosambi’ 

in Ahmednagar district of Western Maharashtra and was confirmed by biological indexing and PCR as “Ca. 

Liberibacter asiaticus”. Four different citrus cultivars viz. ‘Mosambi’, ‘Rangpur’ lime, ‘Cleopatra’ mandarin 

and acid lime that showed variable symptoms of suspected greening in the field were used in the present 

study. Presence of “Ca. Liberibacter spp.” was confirmed by PCR amplifications using 16S rDNA primers. PCR 

amplifications and sequences comparison of another well conserved regions β operon’s subunits rplA-rplJ 

revealed the pathogen as “Ca. Liberibacter asiaticus”. There was variability in symptoms expression and 

sequences of HLB isolates from different citrus cultivars in this geographical region, but all isolates were 

closely related to “Ca. Liberibacter asiaticus” strains and no similarity was observed with the Africanus strain. 


S12P43 

Analysis of citrus huanglonbing spatial dynamics in non-intervened groves of Cuba by Spatial 

Analysis by Distance Indices (SADIE) 

Batista L. 1 , Peña I. 1 , Luis M. 1 , Acosta I. 2 , Hernández L. 1 , Llauger R. 1 , Casín J.C. 3 , and Laranjeira F.F. 4 

1 Instituto de Investigaciones en Fruticultura Tropical (IIFT), Fitopatología, Cuba; 2 Empresa de Cítricos Victoria de Girón, Cuba; 3 Centro 

Nacional de Sanidad Vegetal, Cuba; and 4 Embrapa Cassava and Tropical Fruits, Cuba. lochy@infomed.sld.cu 

Huanglongbing (HLB) citrus disease was first reported in Cuba in 2007 associated to the “Candidatus 

Liberibacter asiaticus” bacteria. Due to the presence of the pathogen and its vector Diaphorina citri in 

all citrus areas, it was essential to carry out epidemiological studies aiming at supporting more effective 

management strategies. To achieve this, the presence of symptomatic plants was evaluated bimonthly in 

non-intervened grapefruit and orange groves. Spatial patterns of aggregation were determined by calculating 

SADIE’s Aggregation Index (Ia). Spatial association between plants with HLB symptoms and newly detected 

ones was evaluated using the Association Index (X). The spatial pattern was characterized by the presence 

of diseased plants clusters, which were larger in the highest disease incidence area. Ia values increased with 

time, showing values significantly higher than 1. Likewise, the size of the patch clusters increased, indicating 

an increase in aggregation with time. The largest patch clusters were located in the field edge adjoining 

an old grove with high HLB incidence. Significant spatial association was found in the clustering of existent 

diseased plants and newly detected ones 7 months afterwards. No significant aggregation was found in the 

area with lowest incidence of diseased plants. These results are currently being used to support decisions on 

HLB survey and management in Cuba. 

S12P44 

Identification of tolerance in citrus germplasm for Huanglongbing 


Institute of Horticultural Sciences, University of Agriculture, (IHS UAF FSD PK), Pakistan.citsykk@yahoo.com 

Huanglongbing is a serious threat to the citrus industry around the world. There is no claim of complete and 

long lasting control of the disease still. Identification of tolerance in citrus germplasm is a hope to save the 

industry. Research is going on in the University of Agriculture, Faisalabad, Pakistan to identify tolerance in 

citrus germplasm against Huanglongbing. In an experiment with the above mentioned objective twenty five 

germplasm accessions were raised in the insect proof screenhouse. These accessions were tested and found 

Huanglongbing disease free before inoculation. These accessions were graft inoculated with Huanglongbing 

positive budwood. The budwood was taken from PCR tested Huanglongbing positive plants. Conventional PCR 

was performed after three months of inoculation by using -16s rDNA primers OI1/OI2C and rplKAJL-rpoBC 

operon primers A2/J5 for amplification and they show 1160bp and 703bp bands respectively in positive plants. 

Data regarding the germplasm accessions found Huanglongbing negative and/or positive will be presented. 


S12

Session 13 

FRUIT FLIES 

S13

S13O01 

Application of the Sterile Insect Technique: an effective biological control method against fruit fly 

pests and its contribution to food security, the environment and trade. 

Hendrichs J., Pereira R., and Reyes J. 

Joint Food and Agriculture Organization and International Atomic Energy Agency Division (Joint FAO/IAEA Division), Insect Pest Control 

Section, Austria. J.Hendrichs@iaea.org 

Fruit flies are major pests destroying globally large portions of fruit and vegetable production. They require 

intensive insecticide applications, which lead to resistance problems and the surge of secondary pests. 

Many subtropical and tropical countries cannot export these high-value crops because of the presence of 

fruit flies pests. The sterile insect technique (SIT) is a type of insect “birth control” that has been applied 

against tephritid fruit flies on all continents. It is very environment-friendly as it is non-polluting, speciesspecific 

and does not introduce fertile exotic insects. Effective control is achieved when the sterile insects 

are systematically released as part of an area-wide integrated pest management (AW-IPM) approach. It has 

a good track record for the suppression, containment, prevention or eradication of populations of different 

pest fruit flies, achieving very significant socioeconomic impacts in terms of reducing losses and insecticide 

use, leading to a more sustainable pest management and environment for rural communities, and healthier 

commodities for consumers. Furthermore, it has been successfully used to establish pest-free areas and areas 

of low pest prevalence, thereby opening access to lucrative export markets and creating thousands of jobs 

in rural areas. As important, the SIT has been effectively used to eliminate invasive pest outbreaks, thereby 

avoiding the establishment of new fruit fly pests. 

S13O02 

Assessing the effectiveness of sterile males in Mediterranean fruit fly population reduction by 

molecular techniques. 

Juan-Blasco M. 1 , Sabater-Muñoz B. 1 , Argiles R. 2 , Jacas J.A. 3 , Castañera P. 4 , and Urbaneja A. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Unidad Asociada de Entomología UJI-IVIA-CIB CSIC. Centro de Protección 

Vegetal y Biotecnología. Spain; 2 Transformaciones Agrarias SA (TRAGSA), Dpto. de Plagas, Spain; 3 Universitat Jaume I (UJI), Unidad 

Asociada de Entomología UJI-IVIA-CIB CSIC. Departament de CiènciesAgràries i del Medi Natural. Spain; and 4 Centro de Investigaciones 

Biológicas del Consejo Superior de Investigaciones Científicas (CIB CSIC), Unidad Asociada de Entomología UJI-IVIA-CIB CSIC. 

Departamento de Biología Ambiental. Spain. sabater_bea@gva.es 

The success of an area-wide program integrating the Sterile Insect Technique (SIT) against the Mediterranean 

fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) relies on the mating success of the released 

sterile males in the field. However, little is known about the effectiveness of sterile males to mate with wild 

females in the field and how these matings contribute to reduce wild populations of C. capitata in Spain. 

As a first step to answer these questions, wild females, wild males and Vienna-8 (V8) sterile males were 

exposed to three different host fruits (apples, clementine mandarins and sweet oranges) under five sterile 

males release ratios (1:0, 1:1, 1:5,1:10 and1:20) under laboratory conditions. By means of sterile sperm ID 

method, V8 sperm was positively detected in those females exposed to the male ratios 1:5, 1:10 and 1:20 in 

the three host fruits.The highest number of sterile mates was detected on clementine mandarins, although 

it was on apple where more C. capitata progeny were found. Secondly, the same release ratios were assayed 

under field conditions on caged-clementine trees, using sentinel apples as the most susceptible host fruit to 

be attacked. Sterile V8 sperm in wild females was positively correlated to the ratio of V8 males released and 

more importantly, the C. capitata progeny was also positively correlated to the percentage of sterile mates. 

These results confirm the usefulness of molecular detection of V8 sperm to predict C. capitata population 

reduction under field conditions. Implications of these results on the efficacy measurement of a SIT program 



S13

S13 

S13O03 

Multiple insecticide resistance traits in a field derived population of the Mediterranean fruit fly, 

Ceratitis capitata. 

Ortego F., Couso-Ferrer F., Arouri R., Huertas-Rosales O., Beroiz B., Perera N., Cervera A., Hernández-Crespo P., and 

Castañera P. 

Centro de Investigaciones Biológicas (CIB - CSIC), Departamento de Biología Medioambiental, Spain. ortego@cib.csic.es 

Resistance to malathion is widely spread in Spanish field populations of the Mediterranean fruit fly, Ceratitis 

capitata (Wiedemann) (Diptera: Tephritidae). A malathion resistant strain (W-4Km), derived from a field 

population collected in Castellón in 2004, was obtained by laboratory selection. The W-4Km strain was 176fold 

more resistant to malathion than a susceptible C strain, established from wild C. capitata collected at 

non-treated experimental fields in Valencia in 2001, and maintained in our laboratory without exposure to 

insecticides. The resistance mechanism of the W-4Km strain was found to be associated with a single point 

mutation in the target acetylcholinesterase (AChE). Further laboratory selection of this strain with malathion 

or other insecticides led to a highly malathion resistant strain (W-10Km, about 500-fold resistance), a lambdacyhalothrin-resistant 

strain (W-1Kl, 205-fold), and a spinosad resistant strain (Xabia-W-100s, resulting from 

the cross of the W-4Km strain with a field derived population, over 200-fold). A novel resistance mechanism 

associated with the AChE gene has been discovered in the W-10Km strain. The synergistic activity of PBO 

and DEF in the W-1Kl strain suggests that metabolic resistance mediated by both P450s and esterases may 

be involved in the development of resistance to lambda-cyhalothrin. However, none of the mechanisms 

previously described appear to be implicated in the resistance to spinosad. These results indicate that multiple 

resistance traits are present in the field derived population. Moreover, we have shown that resistance to 

lambda-cyhalothrin and spinosad can rapidly evolve to levels that may compromise their effectiveness in the 

field. 

S13O04 

Citrus fruits and the Mediterranean fruit fly. 

Papadopoulos N.T. 1 , Papachristos D.P. 2 , and Ioannou C.S. 1 

1 University of Thessaly, Laboratory of Entomology and Agricultural Zoology, Greece; and 2 Benaki Phytopathological Institute, 

Entomology and Agricultural Zoology, Greece. nikopap@uth.gr 

The Mediterranean fruit fly (medfly), Ceratitis capitata (Diptera: Tephritidae) is considered one of the most 

important pests of citrus fruits. Recent and older studies demonstrate a variable degree of susceptibility 

among different citrus species to medfly infestations. They indicate that the chemical properties of the citrus 

fruit rind are the most important barrier prohibiting survival and development of medfly immature stages. 

The toxic properties of rind vary considerable among different citrus species as a result of quantitative and 

qualitative (composition) aspects of citrus essential oils. Effects of fruit flesh on biological traits of larvae do not 

vary much among different citrus species. On the other hand, citrus essential oils affect, in a variable manner 

among different fruit species, a range of adult behavioral traits. For example, male medflies are attracted 

to citrus essential oils while exposure to them increases mating competitiveness over non-exposed males. 

Likewise, citrus oils regulate female ovipositional decisions. The current paper provides a comprehensive 

account of the complex interactions between medfly and citrus plants. Practical and theoretical implications 


S13O05 

Looking inside the chemosensory system of the medfly Ceratitis capitata 

Malacrida A.R., Gomulski L.M., Scolari F., Falchetto M., Siciliano P., Manni M., and Gasperi G. 

University of Pavia (UNIPV), Department of Biology and Biotechnology, Italy. malacrid@unipv.it 

The Mediterranean fruit fly, Ceratitis capitata is an important pest of citrus crops and this has led to the 

development of extensive control programmes. Apart from traditional insecticide-based control methods 

that are often associated with mass-trapping, it has become a model organism in Sterile Insect Technique 


(SIT) application. Both mass-trapping and the SIT are dependent on the availability of efficient species-specific 

attractants. For the SIT the availability of attractants is critical for monitoring the size and composition of the 

target and the sterile populations. The efficiency of an artificial attractant depends on its ability to deceive 

the exquisite sensitivity and selectivity of an insect’s chemosensory system. Little is known about the genes, 

receptors and the processes that mediate chemosensory behaviours in the medfly. We are characterizing 

the medfly chemosensory system using functional molecular, protein, behavioral and electrophysiological 

approaches. 

The study of the molecular basis of the perception of odours and pheromones in C. capitata, apart from 

providing new information on the reproductive biology of this invasive species, also represents the basis for 

future developments. The identification of the specific odours that bind to proteins involved in chemoreception 

could lead to the development of new attractants and repellents that could have an important role in 

environmentally friendly biological control methods. This would form the basis for the extension of such 

biotechnological approaches to other species of agricultural and medical importance. As such this represents 

yet another example of the key role of the medfly as a model organism for innovative control programmes. 

S13O06 

Field infestation and suppression of the invasive fruit flies Bactrocera invadens on citrus in 

Kenya. 

Ekesi S. 

International Centre of Insect Physiology and Ecology (ICIPE), Plant Health, Nairobi, Kenya. sekesi@icipe.org 

Field infestation rates of the invasive fruit fly species, Bactrocera invadens on Citrus spp. was determined at 

different localities in Kenya. The level of infestation varied with location ranging from 3.0 to 36%. At some of the 

locations and especially at high elevations, B. invadens frequently shared the same fruit with the indigenous 

fruit fly species Ceratitis capitata but often occurred at higher numbers than C. capitata. Among the five 

Citrus species sampled, sweet oranges (Citrus sinensis) recorded the highest level of infestation compared 

with the other species. There was a significant inverse relationship between numbers of flies per kg of fruits 

and elevation at which citrus fruits were collected. Field trail were conducted on sweet oranges to compare 

catches of B. invadens in Multilure trap baited with 4 commercial food-based attractants namely Mazoferm®, 

Torula® yeast, Hymlure®, and Nulure®. Mazoferm and Torula yeast were the most effective attractants and 

captured between 2.4-2.8 times and 3.2-4.1 times more flies, respectively than the standard Nulure. In field 

suppression trials using Mazoferm-Spinosad bait spray, % reduction in B. invadens population relative to 

the control was 82% at 4-weeks after bait spray and 94% at 8-weeks after treatment application. At harvest, 

percentage fruit infestation was significantly lower in the treated orchards (5%) compared with the control 

orchards (39%) and demonstrates the efficacy of bait spray for the management of B. invadens on citrus. 

S13O07 

Quarantine mitigation for Tephritid fruit fly pests in citrus. 

Liquido N. J. 1 , and Griffin R. L. 2 

1United States Department of Agriculture (USDA-APHIS-PPQ-CPHST), Plant Epidemiology and Risk Analysis Laboratory, USA; and 

2United States Department of Agriculture (USDA-APHIS-PPQ-CPHST), Plant Epidemiology and Risk Analysis Laboratory, USA. 

Nicanor.J.Liquido@aphis.usda.gov 

The fruit flies of the family Tephritidae impose enormous constraints on the diversification of agricultural 

production and expansion of agricultural trade around the world. Their polyphagous feeding habits and 

persistent ecological adaptiveness distinguish them among the worst invasive pest species requiring vigilant 

detection, effective suppression, and regimented area-wide eradication. Among the suitable host plants of 

quarantine-significant fruit flies belonging to genera Anastrepha, Bactrocera, and Ceratitis are Citrus spp. 

Rigorous quarantine procedures and regulatory safeguards are required and enforced to prevent the spread 

of these fruit flies through legitimate international and domestic movement of citrus. 


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With abundant production worldwide, Citrus spp. rank among fruit crops with the highest commercial value. 

Citrus spp. have the distinction of encompassing extensive basic research and validation studies aimed at 

developing acceptable and efficacious Probit 9 quarantine mitigations, including fumigation, high-temperature 

forced-air, vapor heat, cold, and irradiation treatments. We will review and discuss conventional Probit 9 

treatment schedules and alternative risk-based (e.g., conditional non-host, less than Probit 9) mitigation 

approaches in achieving quarantine security for fruit flies in citrus. 

S13P01 

The transcriptome and protein baits of Bactrocera dorsalis (Diptera: Tephritidae). 

Zheng W., Zhang W., and Zhang H. 

Huazhong Agricultural University (HZAU), College of Plant Science and Technology, China. hongyu.zhang@mail.hzau.edu.cn 

Bactrocera dorsalis is a destructive polyphagous pest feeding on more than 250 fruits and vegetables. To 

understand molecular mechanisms of B. dorsalis’s behavior, to finally effectively control it, its extensive 

transcriptome was produced using the Roche 454-FLX platform, and a new bait based on protein X was 

developed. We obtained over 350 million bases of cDNA derived from the whole body of B. dorsalis at 

different developmental stages. In a single run, 747,206 sequencing reads with a mean read length of 382 bp 

were obtained. These reads were assembled into 28,782 contigs and 169,966 singletons. The mean contig 

size was of 750 bp. Additionally, we identified a great number of genes that are involved in reproduction 

and development, as well as genes that represent nearly all major conserved metazoan signal transduction 

pathways. Furthermore, transcriptome changes during development were analyzed. A new bait based on 

protein X was developed. Among 12 proteins tested, protein X was most attractive to both females and males 

of B. dorsalis. After a series of lab bioassays, a mixture of protein X, brown sugar and white vinegar was 

chosen as the bait to be used in the field bioassays. Methyleugenol (ME) and a sugar/vinegar mixture were 

designed as the two controls. The results suggested that the protein X bait had the highest attractant rate, 

and the number of trapped flies (83.5 males and 61 females) by this bait was 4.1 and 9.2 times of that in the 

control of ME (35.5 males and 0 females)and sugar/vinegar mixture (5.7 males and 10 females), respectively. 

Acknowledgements: This work is supported by the earmarked fund for Modern Agro-industry Technology 

Research System of China (No. CARS-27), and Special Fund for Agro-scientific Research in the Public Interest 

(no. 200903047). 

S13P02 

The potential benefits of using engineered Medfly to improve the efficacy and to reduce the cost 

of the Sterile Insect Technique: RIDL strain OX3864A 

Slade G. 1 , Koukidou M. 1 , Leftwich P.T. 1 , Rempoulakis P. 1 , Economopoulos A. 2 , Vontas J. 2 , and Alphey L. 1 

1 Oxitec Limited (Oxitec), United Kingdom; and 2 University of Crete (UOC), Department of Biology, Greece. glen.slade@oxitec.com 

The Mediterranean fruit fly (Medfly, Ceratitis capitata Wiedemann) is the most destructive insect pest 

worldwide, infesting over 300 types of fruits, vegetables and nuts. Current control measures include 

insecticides, lures and the Sterile Insect Technique (SIT). Traditional SIT involves releasing large numbers of 

laboratory-reared, radiation-sterilized males into infested areas where they mate with wild females who then 

produce non-viable progeny. The efficacy of SIT depends upon factors including the overall fitness and mating 

competitiveness of the insects; cost drivers include production methods and required release numbers. 

The engineered Medfly strain OX3864A incorporates a repressible female-specific lethality system enabling 

population suppression without the cost or fitness penalty of irradiation. The female-specific nature of the trait 

enables simple production of male-only release cohorts, while its heritability means that a given suppression 

level can be achieved with fewer insects, compared to conventional SIT. The strain also has heritable genetic 

fluorescence, making field monitoring more reliable. Laboratory and field trials with OX3864A showed 100% 

efficacy in separating sexes, mating competitiveness comparable to wild type and the ability to suppress and 

then eradicate a stable wild-type Medfly population in less than three months. Hence OX3864A can improve 

the efficacy and financial viability of using SIT to control field populations of Medfly. 


S13P03 

An early step toward the development of a method to predict Mediterranean fruit fly adult 

emergence under different soil moisture and temperature regimes 

Garrido-Jurado I., Valverde-García P., and Quesada-Moraga E. 

University of Córdoba (UCO), Agricultural and Forestry Sciences, Spain. g72gajui@uco.es 

The most important insect pest of citrus crops in the Mediterranean Basin is the medfly Ceratitis capitata 

(Wiedemann). The fly lays its eggs in citrus fruit and the larvae feed and grow in the mesocarp. During 

development, third instar larvae drop from fruits to the ground, burrow into the soil, and form a puparium 

overwintering as pupa several cm below the soil. To this end, entomapathogenic fungi that have the advantage 

of contact action, may be used for medfly microbial control either targeting adults or pupating larvae and pupae 

in the soil beneath the tree canopy. However, optimizing the timing of soil fungal application for maximum 

pupa and adult control at the onset of adult emergence from the soil would need a better understanding of 

the effect of soil temperature and humidity on pre-imaginal development. An approach based on a lognormal 

parametric survival model was used to define the effects of soil moisture and temperature on pre-imaginal 

medfly mortality and to understand the relationship between both factors and their interaction as influences 

on the development of pre-imaginal medflies in the soil. The number of days required for the immature flies 

to complete their development and reach the adult stage (DT) were studied at five temperatures (15, 20, 

25, 30 and 35ºC) and under five soil moisture regimes 1, 5.0, 9.0, 13.0 and 17.0% (wt:wt).The model was 

significant for C. capitata pre-imaginal development, with DT 50 (the development time for 50% of the preimaginal 

C. capitata to reach the adult stage) ranging from 12.8 to 32.4 days. The average development time 

of the medfly pre-imaginals reaching the adult stage was inversely related to temperature and ranged from 

7.4 to 26.1 days. This model could allow the monitoring of medfly pre-imaginal natural mortality in the soil, 

and therefore, the identification of suitable application times in the medfly lifecycle to achieve the maximum 

degree of adult and pre-imaginal control 

S13P04 

Fruit flies in orange plantations of TicoFrut - Costa Rica 

Camacho H. 

TicoFrut. University of Costa Rica: Fabio Baudrit Agricultural Research Station, Costa Rica. hcamachov@hotmail.com 

TicoFrut Company, Central America’s largest industrial fruit production and processing enterprise, operates 

its plants and plantations in the northern region of Costa Rica. In order to best ascertain how to select the 

most effective and suitable strategies for tephritid control, the diverse tephritid populations were studied. 

The study was carried out at six orange plantations (5,604 hectares) during the harvest periods of 2007 - 

2009. Multilure traps baited with Nu Lure were used, with checks each week. Weekly sampling of 60 ripe 

oranges took place in the same lots where the traps had been placed. Larvae and pupae were collected on 

a weekly basis to identify them. In a total of 1093 traps were set in the plantations, 9,009 dipterous flies 

were collected: among these 69 were Tephritidae, 803 Lonchaeidae, and 907 Ulididae. There were only 2 

Anastrepha ludens and 2 Ceratitis capitata captured. Other flies trapped of the Anastrepha genus: 14 A. 

striata, 33 A. obliqua, 5 A serpentina and, 2 A. fraterculus. None of these specimens were collected in or 

on fruits, but rather only in traps. In the orange crop sampling, 22,920 fruits were analyzed (a total of 382 

samples) and the following flies were obtained: 1,154 Lonchaeidae, 380 Muscidae, but no Tephritidae or 

Ulididae flies. An unforeseen outcome was that the Lonchaeidae Neosilba batesi was caught in traps and in 

the fruit sampling and the number of the Ulididae Xanthacrona bipustulata captured in traps. The largest 

number and widest diversity of tephritids were captured in the area of the industrial plant facilities. In 

2007, 112 traps were set and 1,360 Diptera were collected: 152 were tephritids (6 A. ludens, 1 C. capitata, 

116 A. striata, 18 A. obliqua and 4 A. fraterculus) and 85 lonchaeids. In 2008-2009, 75 traps were set, and 

these caught 383 flies: 28 were tephritids (2 A. ludens, 2 C. capitata, 18 A. striata and 6 A. obliqua). This 

observed greater diversity was due to the large quantity of fruit stored at this locale which were originating 

from many sites around the country. 


S13

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S13P05 

Role of phytosanitary surveillance of Anastrepha spp fruit flies (Diptera: Tephritidae) in the 

context of the citrus industry of Cuba. 

Borges Soto M. 1 , Beltrán Castillo A. 1 , Avalos Rodriguez Y. 1 , Hernandez D. 1 , Sabater-Muñoz B. 2 , and Rodriguez Rubial M. 1 

1 Research Institute of Tropical Fruit (IIFT), Entomology, Cuba; and 2 Instituto Valenciano de Investigaciones Agrarias (IVIA), Entomology, 

Spain. sabater_bea@gva.es 

The phytosanitary surveillance plays an important role in preventing harmful pests of economic and 

quarantine importance. The presence of the fruit flies Ceratitis capitata, Anastrepha ludens, Bactrocera spp 

and Anastrepha spp (Diptera: Tephritidae) on the American continent constitute a potential risk of introduction 

threatening the citrus production of countries in the region. In Cuba, the presence of these fruit flies is not 

registered, however, surveillance of these quarantine pests and for other species of national interest continues. 

Results have been obtained from research on preferred host fruits located in the surroundings of citrus plots, 

revealing the presence and potential risk to citrus of A. suspensa, identified as of quarantine importance in 

countries such as the United States and others. During the period 2010-2012 case studies were conducted 

to characterize, diagnose and train for the strengthening of phytosanitary surveillance of Anastrepha fruit 

flies in citrus production areas in: Ceiba (Artemisa), Victoria de Giron (Matanzas), Arimao (Cienfuegos) and 

Ciego de Avila Citrus Enterprises. To fulfill this objective, the composition of host fruit presence in production 

areas with respect to A. suspensa were evaluated. Host preferences of the main Anastrepha species detected 

and the effectiveness of traps and attractants were determined, and the monitorin system was relocated. 

The information obtained allowed designing the monitoring strategy in production areas. Training, one of 

the most important tools, was developed through seminars and workshops. This result provides inputs to 

the monitoring programs and the procedures that are essential in the development and implementation 

of measures for the phytosanitary surveillance and integrated management of fruit flies in Cuban citrus 

production. 

S13P06 

DECIS TRAP MedFly ® : innovative platform technology for the sustainable management of the 

Mediterranean fruit fly (Ceratitis capitata). 

Wirtz K. 1 , Ramos E. 1 , and Fullana J. 2 

1Bayer CropScience AG (BCS), Development, Germany; and 2Bayer CropScience S.L. (BCS S.L.), Marketing, Spain. 

kai.wirtz@bayer.com 

How does a farmer ensure that his crops meet the multidimensional requirements of the market? Consumers 

become more and more conscious of top-quality, healthy and safe food, the food value chain increasingly 

demands high crop quality and quantity standards and the public awareness on environmental protection 

and sustainable use of natural resources continuously grows. Thus, current production practices and pest 

management solutions of citrus cultivation require a fundamental rethinking. With Decis Trap MedFly ® Bayer 

CropScience has developed a novel platform technology for the control of Mediterranean fruit flies. Decis 

Trap MedFly ® will be one cornerstone of a new sustainable crop solution system based on IPM-principles 

combining biorationals, innovative selective chemical crop protection products and advanced services. The 

novel ready-to-use “attract & kill”-system, which contains the control-agent Deltamethrin and a long-lasting 

insect attractant, enables growers to replace high-risk chemistry and minimize required inputs through 

less chemical treatments while providing a season-long, convenient control of fruit flies - using 50 traps/ 

ha for citrus (at costs/ha of around 200-250 EUR/ha). Bayer CropScience and its partner SEDQ (Sociedad 

Española de Desarrollos Químicos) – a provider of efficient and environmentally friendly solutions for pest 

control based on pheromones and attractants – will expand the Decis Trap ® platform technology to other 

crops and pests. With annual sales of about EUR 7 billion Bayer CropScience is one of the world’s leading 

innovative cropscience companies in the area of crop protection (Crop Protection), non-agricultural pestcontrol 

(Environmental Science), seeds and plant biotechnology (BioScience). 


S13P07 

Potential of secondary metabolites secreted by the entomopathogenic mitosporic ascomycetes 

Beauveria sp. and Metarhizium spp. for medfly Ceratitis capitata adult control. 

Lozano-Tovar M.D., Garrido-Jurado I., and Quesada-Moraga E. 

University of Cordoba (UCO), Agricultural and Forestry Science, Spain. z82lotom@uco.es 

The Mediterranean fruit fly Ceratitis capitata (Wiedemann) is a cosmopolitan pest that feeds on a wide 

range of plants. In citrus crops, it causes important direct and indirect annual costs. Medfly management is 

mainly based on treatments with chemical insecticides, but there are increasing concerns on the effect of 

such compounds on environment and humans. Besides, the new European Directive for the sustainable use 

of pesticides promotes the non-chemical control methods with emphasis on biopesticides. This work was 

performed to search for new insecticidal compounds of natural origin secreted by entomopathogenic fungi 

for medfly control. Crude extracts of several B. bassiana, M. anisopliae and M. brunneum isolates and their 

dialyzed and adialyzed fractions were tested on C. capitata newly emerged adults. Crude extracts from four 

isolates were highly toxic, with mortalities ranging between 87 and 100% at 48 hours. In most cases, the toxic 

fraction of the crude extracts was retained after dialysis 3500 da cut-off membranes. The most active fraction 

was submitted to organic extraction, with methanol and buthanol fractions being highly toxic per os against 

C. capitata. 

S13P08 

Comparison of different food attractants for fruit fly capture (Diptera: Tephritidae) in citrus 

orchards in the state of São Paulo, Brazil 

Rodrigues M.D.A. 1 , Raga A. 2 , Maldonado Jr W. 1 , and Barbosa J.C. 3 

1 Universidade Estadual de Campinas (UNICAMP), Brazil; 2 Instituto Biológico (IB), Centro Experimental, Brazil; and 3 Universidade 

Estadual Paulista (UNESP), Brazil. adalton@biologico.sp.gov.br 

Anastrepha fraterculus (Wiedemann) and Ceratitis capitata (Wiedemann) are the most important fruit fly 

species in Brazil. Both species are responsible for significant losses in citrus production in the State of São 

Paulo. The aim of this study was to compare the efficacy of different food bait attractants for monitoring fruit 

flies in IPM programmes. The experiment was conducted under completely randomized design with seven 

treatments (yellow plastic McPhail traps) and four replications. The treatments were: BioAnastrepha (3% 

v/v), Isca Mosca (3% v/v), Samaritá® (3% v/v), Torula® (3 tablets per trap), Milhocina® plus borax (5% v/v 3% 

p/v), sugar cane molasses (7% v/v) and grape juice Aurora brand (25% v/v). The experiments were performed 

in two seasons, from March until April (season 1) and from November until December 2008 (season 2), in two 

orange orchards (organic and conventional systems) located in Mogi-Guaçu, SP. The number of flies captured 

by each attractant was evaluated weekly during seven weeks. In total 4,327 adults of Tephritidae were 

captured: 3,073 specimens of A. fraterculus and 1,258 specimens of C. capitata. Milhocina plus borax and 

Torula during season 1, and Torula during season 2 were more effective to capture fruit flies. These differences 

were sorted out by Tukey´s test between treatments. In the organic orchard, Torula and BioAnastrepha 

captured significantly more tephritids during season 2. In general, Torula attracted more females than males. 

S13P09 

Evaluation of protein bait laced with various insecticides on the Queensland fruit fly (Diptera: 

Tephritidae): attraction, feeding, mortality and bait persistence 

Mahat K. 1 , and Drew R.A.I. 2 

1 National Plant Protection Centre (NPPC), Department of Agriculture, Thimphu, Bhutan; and 2 International Centre for the Management 

of Pest Fruit Flies (ICMPFF), Griffith School of Environment, Environment, Science, Engineering and Technology, Griffith University, 

Nathan Campus, Queensland 4111, Australia. kiranmahat@gmail.com 

Use of malathion in fruit fly protein bait sprays has raised serious concerns due to its adverse effects on 

non-target organisms. This has necessitated the need to evaluate novel, reduced risk compounds. This 

study evaluated the effects of spinosad, fipronil, malathion and chlorpyrifos mixed with fruit fly protein bait 


S13

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(Mauri Pinnacle protein®) on attraction, feeding and mortality of the Queensland fruit fly, Bactrocera tryoni 

(Froggatt). The effects of outdoor weathering of these mixtures on fly mortality were also determined. 

In field-cage experiment, protein-starved flies showed the same level of attraction to baits containing 

spinosad, fipronil, malathion, chlorpyrifos and protein alone used as control. Female protein-starved flies 

were deterred from feeding on baits containing malathion and chlorpyrifos compared to baits containing 

spinosad, fipronil and protein alone. Baits containing malathion and chlorpyrifos caused higher fly mortality 

and rapid fly knock down than spinosad and fipronil. However, spinosad acted slowly and caused an increase 

in fly mortality over time, causing up to 90% fly mortality after 72-hr. Baits containing malathion and 

chlorpyrifos, applied on citrus leaves and weathered outdoors, had longer residual effectiveness in killing 

flies than spinosad and fipronil. Residual effectiveness of the spinosad bait mixture waned significantly 

after 3 days of outdoor weathering. Results suggest that spinosad and fipronil can be potential alternatives 

for malathion in protein bait sprays. 

S13P10 

Effectiveness evaluation of two attractants, CeraTrap® and Tripack®, for the mass trapping of 

Ceratitis capitata (Diptera: Tephritidae) in citrus orchards in different regions of Tunisia 

Hafsi A., Rahmouni R., Ben Jannet M., Harbi A., and Chermiti B. 

Institut Supérieur Agronomique de Chott-Meriem (ISA-CM), Département des Sciences Biologiques et de la Protection des Végétaux, 

Tunisia. harbi.ahlem@hotmail.fr 

Ceratitis capitata Wiedemann (Diptera: Tephritidae) is a key pest on citrus at worldwide range, being of 

quarantine importance for export issues for countries on which this pest is present. In Tunisia C. capitata is of 

economic importance due to importance of citrus sector. Damages of C. capitata in Tunisia may cause losses 

of about 1.06 millions Dollars (US) per year on Citrus. By this factor, mass trapping is being evaluated for an 

effective control of this pest in citrus. Nowaday, the area covered by mass trapping is of about 300 ha. The 

trials were conducted during 2 years (2010, 2011) with two types of Mediterranean fruit fly mass trapping 

systems CeraTrap® and Tripack® in Citrus orchards in three different geographical regions of Tunisia, under 

different management systems: strictly organic (biotope of Chott-Meriem), semi organic (biotope of Takelssa) 

and finally the conventional (biotope of Mornag). The obtained results showed that the mass trapping of 

C. capitata used under: a) different management systems; b) trees densities, c) Citrus varieties (Maltaise, 

Washington Navel) and d) with or without aerial treatments and localized applications (tasks treatments); is 

able to protect fruits against the Mediterranean fruit fly. The CeraTrap® system showed a similar or even a 

higher effectiveness than the Tripack® system in controlling the Med fly population and both mass trapping 

systems were selective with the non-target fauna. 

S13P11 

Field releases of the larval parasitoid Diachasmimorpha longicaudata in Spain: first results on 

dispersal pattern 

Harbi A. 1 , Beitia F. 2 , Tur C. 3 , Chermiti B. 1 , Verdú M.J. 2 , and Sabater-Muñoz B. 2 

1 Institut Supérieur Agronomique de Chott-Meriem (ISA-CM), Département des Sciences Biologiques et de la Protection des Végétaux, 

Tunisia; 2 Instituto Valenciano de Investigaciones Agrarias (IVIA), Entomología, Centro de Protección Vegetal y Biotecnología (PVyB), 

Spain; and 3 Transformaciones Agrarias SA (TRAGSA), Departamento de Plagas, Spain. harbi.ahlem@hotmail.fr 

The Mediterranean fruit fly, Ceratitis capitata (Wiedemann), is a key pest on citrus and other fruit trees in 

the Valencian Community (Spain). Currently it is being controlled by means of chemical applications, masstrapping 

and by the Sterile Insect Technique. As more environmentally safe techniques are being demanded 

by the European Union, a biological control program with parasitoids is also under study at the IVIA research 

station in Valencia. The braconid Diachasmimorpha longicaudata (Ashmead) is a larval parasitoid of several 

Tephritid species, which is being used as biological control agent in several countries (Argentina, Australia, 

Guatemala, Hawaii (USA), Mexico). This species was imported to Spain from Mexico in 2009, and after its stay 

in the quarantine station, it has been adapted to laboratory rearing using medfly as host. The objective of this 

work is to understand parasitoid movement in the open field and its parasitism success under Mediterranean 


climatic conditions, including Tunisian conditions. In this work we show the results of our release assays 

at different citrus areas and under different releases and parasitoid movement and parasitism assessment 

systems. The use of artificially infested sentinel apples arose as the best method to establish the dispersal 

pattern and parasitism assessment of released parasitoids. Application of host odour clues as pre-release 

treatment is discussed. 

S13P12 

Magnet ® MED: A new long-life, ready-to-use “Attract and kill” system to control Mediterranean 

fruit fly, Ceratitis capitata Wiedemann. 

Colás C., Dominguez M., Marti S., and Alfaro C. 

Suterra Europe Biocontrol SL (Suterra), Biocontrol, Spain. mdominguez@suterra.com 

The goal of Magnet Med® is to control the pest bringing the insect to the poison instead to bring the 

poison to the insect. Magnet Med® combines a good stable long-life deltamethrine formulation with a 

long-life female attractant, Unipack®. Unipack® is female lure based on USDA patent and is being applied 

in more than 20.000 ha for mass trapping in Spain citrus area, achieving very good results attracting ratio of 

70/30 females/males. The effectiveness of Magnet Med® as “A&K” system to control C. capitata has been 

demonstrated in many field trials conducted since 2006, in citrus as well as in stone fruits, pome fruits and 

table grapes. In 2011 and 2012, laboratory tests demonstrate that the new deltamethrine formulation, 

exposed under filed conditions, keep affecting the flies during at least 6 months. The attraction power 

of Unipack® was also evaluated under field conditions, showing very high female attraction even after 6 

months of being placed on the field. Those results prove the 6 months lasting of Magnet Med®. It allows 

the grower not only to protect the crop but also to keep affecting the C. capitata population and achieving 

a population decrease year after year. 

This new effective period of the product give the possibility to change the strategy control achieving a longseason 

Medfly control. Moreover, Magnet Med® is shown as ready-to-use product, environmental friendly, 

residues free, very easy to be combined with other fruit fly management strategies and permitted in European 

organic orchards (EU Directive 2092/91). 

S13P13 

Assessment of the efficacy of lure and kill devices for the control of Mediterranean fruit fly in 

citrus orchards. 

Navarro-Llopis V., Primo Millo J., Vacas S. 

Instituto Agroforestal del Mediterráneo (CEQA), Universitat Politècncia de València, Spain. vinallo@ceqa.upv.es 

Due to new restrictions in the use of insecticides by governments and the increasing social awareness in its 

use, the development of new control methods has become essential to manage this pest. Bait sprays with 

spinosad, mass trapping and lure and kill techniques have been the base for new integrated pest management 

programs. In this work, three-years field trials were conducted in three citrus areas to test the efficacy of 

attract and kill devices against mass trapping and spinosad or organophosphate plus bait treatments. In the 

three trials, Magnet® MED attract and kill device, Spintor® treatments and mass trapping achieved good 

control of C. capitata populations, as confirmed by low percentages of damaged fruit in the assessments 

performed during the harvest period. On the contrary, fly population levels on plots untreated or treated with 

a low efficacy attract and kill prototype device increased more than three times, regarding to the populations 

recorded in the rest of treated plots. The same effect was observed on fruit damage, obtaining from six to 

eight times less damage with Magnet® MED and spinosad treatments respectively, regarding the attract and 

kill prototype devices. Untreated plots registered 20 fold fruit damage than treated plots. As a conclusion, 

using an effective attractant, conventional trapping systems can be replaced with cheaper and easier to 

handle attract and kill devices. The advantages of using lure and kill devices with respect to conventional 

mass trapping systems are stressed. 


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S13P14 

Evaluation of mass trapping technique for control of Ceratitis capitata Wiedemann (Diptera: 

Tephritidae) in citrus orchards of Northern Iran. 


Agricultural and Natural Resources Research Centre of Mazandaran, Plant Protection, Iran. mafiali@hotmail.com 

The Mediterranean fruit fly (Medfly), Ceratitis capitata is one of the most destructive pests of citrus fruits in 

Mazandaran province of Iran. The mass trapping technique based on the use of female and male-targeted 

attractants was carried out for the first time in two citrus groves (0.5 ha) using Tephri-traps (baited with Cera 

Trap as a food attractant for females) and Jackson trap (baited with Trimedlure as a sexual attractant for 

males) in 2008. In total 50 traps were installed, distributed on one-third of citrus trees in treated plots. All 

traps were placed 1.5-1.8 m above the ground, slightly inside of tree canopy. For each Jackson trap, three 

Tephri -traps were set. Monitoring of adult population of Medfly in the control plot was performed by using 

two Jackson traps. Tephri-traps were serviced once every two weeks and trimedlure dispensers of Jackson 

traps were replaced every month. The effect of mass trapping technique was based on randomly examining 

500 fruits every week from September until harvesting time (i.e. November), for production of viable adults. 

At the end of experiment, approximately 8939 female and 2656 male flies were recorded in the treated 

plot [what about the control plot]. Data analysis indicated significant differences (P

Session 14 

VIRUS AND VIRUS LIKE DISEASES 

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S14O01 

Recent developments on Citrus tristeza virus research 

Folimonova S. 

University of Florida, Citrus Research and Education center, Plant Pathology, USA. svetlana@ufl.edu 

Citrus tristeza virus (CTV) causes two citrus diseases that cause economic losses in citrus production globally: 

quick decline on sour orange rootstocks and stem pitting. Recent research results from several labs around 

the world provided valuable contributions that greatly increase our understanding of the virus-citrus host 

interactions as well as generate a necessary foundation for development of effective procedures to manage 

CTV diseases. Our lab demonstrated that p33, p13, and p18 proteins are required for systemic infection of some 

citrus varieties, suggesting that genes of these nonconserved proteins were acquired during virus evolution to 

extend its host range. Another interesting discovery was demonstration that stem pitting does not necessarily 

result from a specific sequence or protein, but from a balance between the expression levels of different viral 

genes. Several important results were obtained by IVIA researchers in Valencia, Spain. One of them was the 

development of a long-awaited successful strategy for obtaining transgenic resistance against CTV by expression 

of untranslatable versions of genes encoding the three silencing suppressors of CTV, p25, p20, and p23. Crossprotection 

has been an effective management procedure that has allowed economic production of citrus in 

some regions in which endemic severe isolates of CTV made citrus production unprofitable. However, finding 

protecting isolates has been empirical and rarely successful. Research results obtained by our lab has advanced 

our understanding of how CTV cross-protection works, showing that exclusion works only for isolates within 

a strain, and, thus, provided a “recipe” for selection of protective isolates. A next frontier of virus biology is 

developing an understanding of how viral populations form, induce symptoms, and react to cross protect. Some 

progress in this area has been done. These and other recent contributions will be discussed. 

S14O02 

Large scale survey of Citrus tristeza virus (CTV) and its aphid vectors in Morocco 

Afechtal M. 1 , Djelouah K. 2 , Cocuzza G. 3 , and D’Onghia A.M. 2 

1 National Institute of Agricultural Research (INRA), Plant Protection, Morocco; 2 Mediterranean Agronomic Institute (IAMB), Integrated 

Pest Management of Mediterranean Fruit Crops, Italy; and 3 University of Catania (UNICT), Science and Phytosanitary Technologies, 

Italy. mohamedafechtal.inra@gmail.com 

A survey of Citrus tristeza virus (CTV) was carried out in the main Moroccan citrus growing areas (Souss, Gharb, 

Moulouya, Tadla, Haouz, Loukkos). A total of 3,208 plants from commercial groves, nurseries, plots of budwood 

sources and varietal collections were analyzed by DTBIA. About 26% of the tested trees proved to be CTVinfected 

in the groves, mainly in Loukkos region with a 60% infection rate. On the contrary, just a few infected 

trees were detected in Souss and Gharb regions. No CTV infections were found in the remaining investigated 

sites. CTV vectors were monitored in Gharb and Loukkos regions. Aphis spiraecola (56%) and A. gossypii (33%) 

were the most abundant aphid species, while no evidence of Toxoptera citricidus was reported. Four out of six 

selected Moroccan CTV isolates showed, by coat protein gene sequencing, the highest nucleotide homology 

with the Spanish mild isolate T385. The remaining isolates, from Loukkos, clustered close to the Portuguese 

19-21 reference strain; one of these induced a mild stem pitting on Duncan grapefruit by biological indexing. 

This study confirmed CTV genetic diversity in some Moroccan orchards. The finding of the stem pitting form 

represents a serious threat to the Moroccan citrus industry, mainly if T. citricidus is introduced in the country. 

S14O03 

Capillary electrophoresis-single–strand conformation polymorphism and multiple molecular 

marker genotyping allow a rapid differentiation of CTV isolates 

Licciardello G. 1 , Russo M. 1 , Daden M. 2 , Bar-Joseph M. 3 , and Catara A. 1 

1 Parco Scientifico e Tecnologico della Sicilia (PSTS), Italia; 2 International Plant Analysis and Diagnostics S.r.l. (IPADLAB), Italia; and 

3 GimlaoTec, Israel. acatara@pstsicilia.it 

Despite the noticeable sensitivity to Citrus tristeza virus (CTV), the sour orange rootstock remains popular in 

some Mediterranean areas because of its horticultural advantages. Since some trees remain symptomless, 


S14

S14 

even if infected, an investigation was developed to differentiate between decline and non-decline CTV 

isolates in view of potential management strategies of the disease. Furthermore, the importance of genetic 

similarities between the protecting and challenging isolates in cross protection point out the importance of 

molecular characterization of CTV isolates. In this study we have evaluated the recently developed capillary 

electrophoresis-single–strand conformation polymorphism (CE-SSCP) method of differentiation associated 

with multiple molecular markers (MMM) assay to screen CTV isolates collected from surviving trees in areas 

severely affected by CTV decline on sour orange rootstock. Analysis of the population structure based on the 

PCR products of coat protein (p25), p23 and p27 genes and genotyping by MMM allowed the selection of nine 

mild and seven severe isolates. Interestingly, only two of the selected mild isolates have shown a T30 single 

genotype whereas seven reacted also with the T3 and/or T36 and/or VT markers. However, phylogenetic 

analysis on p23 or p25 nucleotide sequences revealed that all of them showed a close similarity with the 

T30 and T385 CTV isolates. Evaluation of cross protecting ability of mild isolates is still in progress on sweet 

orange/sour orange, sour orange and Duncan grapefruit growing in a growth chamber. 

S14O04 

Genetic and biological stability of Citrus tristeza virus (CTV) infecting the non-natural host 

Nicotiana benthamiana 

Navarro-López J. 1 , Ruiz-Ruiz S. 2 , Moreno P. 1 , and Ambrós S. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Moncada, Valencia, Spain; and 

2 Instituto de Biología Molecular y Celular de Plantas (IBMCP), Valencia, Spain. sambros@ivia.es 

Although citrus is the only natural host of Citrus tristeza virus (CTV), agroinoculation of Nicotiana benthamiana 

(NB) plants with an infectious cDNA clone of CTV-T36 results in systemic infection of this non-natural host. 

Since replication in NB might affect CTV biological and molecular characteristics, we analyzed viral populations 

of CTV-T36 and T36-GFP (expressing the gfp gene) after successive passages in NB. First we optimized a NBto-NB 

graft-transmission procedure that enabled systemic infection of receptor plants in 1-2 months. The 

consensus full-genome sequence of the first CTV-NB populations was identical to that of the cognate cDNA 

clones. The CTV populations of passage 5 (P5) showed just 1 (CTV-T36-GFP) or 6 (CTV-T36) aminoacid (aa) 

changes in ORF1a regions with no functional relevance, whereas the P11 populations had 12 (CTV-T36-GFP) 

or 8 (CTV-T36) aa substitutions in ORFs1a, 1b, p33, p61, p18, p20 and/or p23, with 5 of these changes being 

common to both lineages. Two of the p23 substitutions in CTV-T36 were in the Zinc finger domain without 

affecting its structure. The infection rate in successive NB passages was similar, albeit viral titer increased and 

the time for systemic infection and symptom appearance was shorter. Virions from P5 and P11 NB plants 

infected 100% of the receptor alemow plants as did the parental citrus virions. Symptoms incited by citrus 

and NB virions in Mexican lime, Pineapple sweet orange, Duncan grapefruit and sour orange were also similar. 

S14O05 

Citrus tristeza virus enhances the titer of Citrus dwarfing viroid in co-infected Mexican lime 

plants through p23 expression 

Serra P. 1 , Bani Hashemian S.M. 1 , Fagoaga C. 1 , Romero J. 1 , Bertolini E. 1 , Ruiz-Ruiz S. 2 , Gorris M.T. 1 , and Durán-Vila N. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; and 2 Instituto de Biología 

Molecular y Celular de Plantas (IBMCP), Valencia, Spain. duran_nur@gva.es 

Several virus and virus-like pathogens have been reported naturally infecting citrus. Citrus viroids are spread 

worldwide, usually as latent infections, whereas Citrus tristeza virus (CTV), which is the causal agent of the 

Tristeza disease, affects many citrus growing areas. Although many citrus trees are co-infected with CTV and 

viroids, there is no information regarding interaction between these two types of citrus pathogens. Northern 

hybridisation analysis of Etrog citron (Citrus medica), the experimental host for viroid bioassay, singly infected 

with Citrus dwarfing viroid (CDVd) or co-inoculated with CDVd and CTV revealed that the viroid titer is not 

affected by the presence of CTV. Unexpectedly, a similar assay using the CTV sensitive indicator host Mexican 

lime (C. aurantifolia), showed that the viroid titer was significantly enhanced by the presence of CTV. Since CTV 

encodes three distinct proteins (p25, p23 and p20) that have been characterized as silencing suppressors, an 


assay was performed to find out if the increased viroid titer was related to suppression of post-transcriptional 

silencing. Transgenic Mexican limes expressing each one of these proteins were inoculated with CDVd. 

Northern hybridisation analysis showed that, in plants expressing p23, viroid accumulation was enhanced 

at similar levels as in plants co-infected with CTV. These results indicate that the expression of p23 via CTV 

infection or via transgenic plants alters the silencing mechanism implicated in host defence, supporting the 

hypothesis that viroids are targets of the RNA silencing machinery of their hosts. 

S14O06 

The p23 protein encoded by Citrus tristeza virus: fine dissection of its determinants for nucleolar 

localization and for suppression of RNA silencing and pathogenesis 

Ruiz Ruiz S. 1 , Soler N. 2 , Sánchez-Navarro J. 1 , Fagoaga C. 2 , López C. 3 , Navarro L. 2 , Moreno P. 2 , Peña L. 2 , and Flores R. 1 

1Instituto de Biología Molecular y Celular de Plantas (IBMCP), Valencia, Spain ; 2Instituto Valenciano de Investigaciones Agrarias (IVIA), 

Centro de Protección Vegetal y Biotecnología, Moncada, Valencia, Spain; and 3Instituto de Conservación y Mejora de la Agrodiversidad 

Valenciana (COMAV), Valencia, Spain. suruirui@upvnet.upv.es 

One of the three RNA silencing suppressors (RSS) encoded by Citrus tristeza virus (CTV) is p23, a RNA-binding 

protein of 209 amino acids that also is a pathogenic determinant when expressed ectopically in citrus. Confocal 

microscopy of Nicotiana benthamiana in which the fusion p23-GFP was transiently expressed revealed its 

accumulation in nucleolus, Cajal bodies and plasmodesmata, thus being the first closterovirus protein with 

a nucleolar localization signal (NoLS). Assay of seven truncated versions of p23 showed that regions 50-86 

and 100-157 (excluding fragment 106-114), both with basic motifs and the first with a Zn-finger domain, 

contain a NoLS bipartite. Further examination of ten point-mutants delimited this signal to three Cys of the 

Zn-finger and some basic amino acids within and preceding it, and to fragment 143-155 with six basic amino 

acids. Essentially all deletions and substitutions annulled RSS activity of p23 (in transgenic N. benthamiana 

expressing constitutively GFP), implicating most p23 regions in this activity. Expression in N. benthamiana of 

p23 as a subgenomic RNA of Potato virus X induced necrosis. This phenotype only was preserved in deletion 

mutant 158-209 and in one point-mutant, showing that the Zn-finger and flanking basic motifs are part of the 

pathogenic determinant. Ectopic expression of p23 and some deletion mutants in transgenic Mexican lime 

delimited a similar determinant, suggesting that p23 affects related pathways in citrus and N. benthamiana. 

S14O07 

Viruliferous Brevipalpus phoenicis gradient from Citrus Leprosis affected trees 

Bassanezi R.B. 1 , Montesino L.H. 1 , and Novelli V.M. 2 

1Fundo de Defesa da Citricultura (Fundecitrus), Departamento Científico, Brazil; and 2Centro APTA Citros Sylvio Moreira - Instituto 

Agronômico de Campinas (Centro APTA Citros Sylvio Moreira - IAC), Brazil. rbbassanezi@fundecitrus.com.br 

Citrus leprosis, caused by Citrus leprosis virus (CiLV-C) transmitted by Brevipalpus phoenicis mite, is important 

in Brazil and its control is mainly based on mitecide sprays. A weak relation between spatial distribution of 

leprosis symptomatic trees and mite infested trees was observed in previous studies. Diseased trees were 

much more aggregated than mite infested trees. This could be explained by a limited movement of mites 

and the high dependence of viruliferous mites on symptomatic citrus trees. The aim of this work was to 

assess the viruliferous mite gradient from citrus leprosis affected trees. Surveys were conducted in sweet 

orange citrus blocks in which all trees were inspected for the presence of symptoms and the mite vector. 

Symptomatic trees and mite infested trees were spatially located and 5-mite samples from each infested 

tree were analyzed by RT-PCR for CiLV-C. From 163 samples collected on healthy trees, only 37.4% were 

CiLV-C positive, and even from 337 samples from symptomatic trees, only 37.7% were positive, confirming 

that most of the mite population was non-viruliferous. Out of 178 CiLV-C positive samples, 71.3% were from 

symptomatic trees, 95% were found within 7 m around a symptomatic tree, and no positive sample was 

found more than 23.5 m away from a diseased tree. The frequency of viruliferous mite samples (y, in %) as a 

function of minimum distance from a leprosis symptomatic tree (x, in m) was fitted to a negative exponential 

model y=71.exp(-0.43 x). 


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S14O08 

New generation sequencing platforms for detection and characterization of viruses and viroids in 

citrus 

Olmos A. 1 , Bertolini E. 1 , Varveri C. 2 , Candresse T. 3 , Martínez M.C. 1 , Pina J.A. 4 , and Cambra M. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; 2 Benaki Phytopathological 

Institute (BENAKI), Laboratory of Virology, Greece; 3 Institut National de la Recherche Agronomique (INRA) and Université de Bordeaux, 

Virology, France; and 4 Generalidad Valenciana, Consellería de Agricultura, Alimentación y Agua, Servicio de Sanidad Vegetal, Spain. 

aolmos@ivia.es 

The accumulation of virus-derived small interfering (si) RNAs (21-24 nucleotides) induced by Dicer recognition 

of dsRNA formed during viral replication can be analyzed by next generation sequencing technologies, namely 

Ion Torrent and Illumina. This strategy was compared with biological indexing for the analysis of several citrus 

samples. Large contigs corresponding to virus species, such as Citrus tristeza virus, allowed their detection 

and full genome reconstruction through subsequent mapping of the specific siRNAs against several reference 

isolates. At the same time, bioinformatic analysis allowed reconstruction of whole genomes of viroids present, 

such as Hop stunt viroid, Citrus exocortis viroid, Citrus viroid III (CVdIII) and Citrus viroid IV (CVdIV). Results from 

both platforms not only were in agreement with indexing results but in addition facilitated identification of 

CVdIII and CVdIV, which cause inconspicuous symptoms in indicator plants. Both Ion Torrent (300.000-800.000 

sequences) and Illumina (4.000.000-5.000.000 sequences) platforms could further generate contigs for viruses 

for which no sequence information was available, allowing reconstruction of genomes de novo. Next generation 

sequencing is a very powerful technology, much faster (15 days) and less costly (currently ~600€/sample) than 

biological indexing, that could greatly simplify routine diagnosis and characterization of known plant pathogens. 

This molecular tool has also the potential to identify poorly or uncharacterized graft-transmissible agents. 

S14O09 

Deep sequencing of viroid-derived small RNAs from citron 

Cao M.J., Su H.N., Yang F.Y., Chen H.M., and Zhou C.Y. 

National Engineering Research Center for Citrus, Citrus Research Institute, Southwest University; College of Plant Protection, 

Southwest University, Chongqing, 40072, People’s Republic of China. mengjic@ucr.edu 

Citrus are natural hosts of seven viroid species of the family Pospiviroidae. Although there is little information 

about the pathogenesis of citrus viroids, several experiments indicated that viroid derived small RNAs (sRNAs) 

are key effectors of viroid pathogenesis. To understand the host RNA silencing defence induced by citrus viroids, 

we examined by deep sequencing (Solexa-Illumina) the sRNAs of leaves from three viroid-infected and one 

healthy citron. Each infected citron plant contained 4 to 6 citrus viroids and displayed typical viroid symptoms. 

Our data show that: (a) Citrus viroid sRNAs represent about 7% of the total sRNAs. (b) Citrus viroid sRNAs are 

predominantly of 21- and 22-nt, with different viroids yielding a distinct biased distribution of their 5’ nucleotide 

and different accumulation of both RNA polarities. (c) Citrus viroid sRNAs derive mostly from specific regions (hot 

spots) of their RNAs. Most of the (-) polarity viroid-derived sRNAs of CEVd, CBCVd, CVd-V, CVd-VI and CVd-I-LSS 

were from downside of the TR region. CBLVd, HSVd and CDVd have the same hot spot region in different viroid 

combinations. (d)The plant sRNA profile, dominated by the 24-nt sRNAs in the mock-inoculated control, exhibited 

a significant reduction of the 24-nt sRNAs and increase of the 21-nt sRNAs in two viroid-infected citrons. We have 

also determined how viroid influences 21-nt miRNAs accumulation and 24-nt rasiRNAs reduction in citron. 

S14O10 

The complete genome sequence of Citrus vein enation virus (CVEV) obtained through deep 

sequencing of small RNAs 

Vives M.C., Velázquez K., Pina J.A., Moreno P., Guerri J., and Navarro L. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain. cvives@ivia.es 

Citrus Vein Enation (VE), a graft-transmissible disease naturally spread by several aphid species in a persistent 

mode, has been reported in many citrus growing areas. It causes vein enations on leaves and woody galls 


on stems and trunks of sensitive citrus species such as Mexican lime, rough lemon and Citrus volkameriana. 

The disease is currently diagnosed by biological indexing on sensitive indicator plants, an expensive and 

time-consuming method. In order to identify its causal agent and develop specific and reliable molecular 

detection methods, we analyzed small RNAs (sRNAs) from healthy and VE-infected Etrog citron plants by 

deep sequencing using the Illumina Solexa platform. Assembly of VE-associated sRNAs yielded several contigs 

that showed sequence homology with Pea enation mosaic virus 1 (PEMV-1), the type species of genus 

Enamovirus, family Luteoviridae. The gaps between adjacent contigs were filled by RT-PCR amplification, 

cloning and sequencing in order to obtain the complete genome sequence of a new virus, Citrus vein enation 

virus (CVEV). The CVEV genomic RNA has 5983 nt organized in five open reading frames, resembling that of 

PEMV-1, and phylogenetic comparison of amino acid signatures in RNA-dependent RNA polymerases of the 

family Luteoviridae clearly grouped CVEV with PEMV-1. Therefore, we propose that CVEV should be included 

in the genus Enamovirus. A rapid and specific detection procedure was developed based on RT-PCR with 

CVEV-specific primers. 

S14O11 

Deep sequencing of citrus affected by graft-transmissible diseases of unknown aetiology leads to 

discovery of two novel viruses 

Loconsole G. 1 , Giampetruzzi A. 1 , Saldarelli P. 2 , Onelge N. 3 , Yokomi R.K. 4 , and Saponari M. 2 

1 Università di Bari “Aldo Moro”, Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti (DiSSPA), Italy; 2 Consiglio Nazionale 

delle Ricerche (CNR), Instituto di Virologia Vegetale (UOS), Italy; 3 Çukurova University Agriculture Faculty, Plant Protection Department 

(PPD), Turkey; and 4 United States Department of Agriculture-ARS (USDA-ARS), USA. m.saponari@ba.ivv.cnr.it 

Citrus are susceptible to a number of graft- and arthropod-transmitted pathogens. Citrus cultivars vary in 

susceptibility or tolerance to pathogens or strains and may remain symptomless when infected. Established 

tests for known disease agents are used by certification and disease management programs. However, 

diseases with unknown aetiology remain difficult or impossible to diagnose. Illumina next generation 

sequencing (NGS) technology was used to generate sequence datasets from citrus affected by two such 

diseases: Citrus Chlorotic Dwarf (CCDD) (whitefly-transmitted) and Yellow Vein Clearing disease (YVCD) 

(aphid-transmitted). CCDD is the most serious citrus disease in Turkey; YVCD is a graft-transmissible disorder 

observed in lemon and sour orange in Pakistan and India and later in Turkey (2000) and China (2010). 

Contigs from small interfering RNAs were assembled and used to screen sequence homologies against 

the virus database in GenBank. DNA fragments from CCDD-affected plants were used to re-construct a 

circular single-stranded DNA viral genome with homologies to those of geminiviruses. The genome size and 

organization of the provisionally named Citrus chlorotic dwarf-associated virus (CCDaV) was determined 

and indicated it was a highly divergent member of the family Geminiviridae. Similarly, the whole genome 

of a putative filamentous virus associated with CYVCD-affected lemon was reconstructed. The genome 

structure was found to be typical of flexiviruses and led to new serological, biological and molecular 

investigations on the provisionally named Citrus yellow vein clearing virus (CYVCV). The recovered data 

suggested that CYVCV is a new species in the genus Mandarivirus. PCR-based assays for CCDaV and CYVCV 

were developed and serve as important new diagnostic tools for citrus disease management programs in 

Turkey and other citrus-producing regions. 

S14P01 

Genetic variation of Citrus tristeza virus (CTV) isolates from Calabria, Italy 

Fontana A. 1 , Debreczeni D. 2 , Albanese G. 1 , Davino S. 3 , Flores R. 4 , and Rubio L. 2 

1 Università degli studi Mediterranea di Reggio Calabria, Gestione Sostenibile dei Sistemi Agrari e Forestali (GESAF), Italy; 2 Instituto 

Valenciano de Investigaciones Agrarias (IVIA), Centro de Proteccion Vegetal y Biotecnología, Valencia, Spain; 3 Università degli Studi di 

Palermo (UNIPA), DEMETRA, Italy; 5 Instituto de Biología Molecular y Celular de Plantas (IBMCP), Valencia, Spain. 

anna.fontana@unirc.it 

Citrustristeza virus(CTV) isolates differing in pathogenicity have been reported worldwide. Although some 

isolates are asymptomatic, most of them cluster in two groups: i) mild, causing only decline and death 

of citrus species propagated on sour orange rootstocks, and ii) severe, additionally causing stem pitting, 


S14

S14 

stunting and low fruit yield and quality in some varieties regardless of the rootstock used. Characterization 

of CTV isolates and estimation of their genetic variation can provide epidemiological information and be 

useful for disease control. The first CTV outbreaks in Italy appeared in 2002: mild and severe isolates 

in Sicily and mild isolates in the Apulia region (South-Eastern peninsular Italy). In this work, the genetic 

variation of 12 mild and 18 severe CTV isolates from recent outbreaks occurred in the Calabria region 

(South-Western peninsular Italy) was studied. Phylogenetic analysis of CTV p20 gene showed that the 

Calabrian severe isolates clustered with severe isolates from other countries (including Egypt, Argentina 

and India), whereas the Sicilian severe isolates were in other cluster together with severe isolates from 

other countries (including Brazil, Spain, USA and China). This finding suggests distinct introductions for the 

severe isolates from Calabria and Sicily. The nucleotide diversity was very low (0.002), suggesting a rapid 

spread of CTV in Calabria. In another respect, the Calabrian mild isolates clustered with mild isolates from 

California, Florida, Spain and Italy, some of them being identical to the Sicilian mild isolates and suggesting 

that the Calabrian mild isolates could come from Sicily. Their very low nucleotide diversity (0.001) supports 

also a rapid spread. However, the mild isolates from Apulia formed a subgroup with higher nucleotide 

diversity (0.011) probably due to their earlier introduction. 

S14P02 

Incidence, distribution and first identification of Citrus tristeza virus by RT-PCR in citrus orchards 

in South Western Nigeria 

Adediji A.O. 1 , Atiri G.I. 1 , and Kumar P.L. 2 

1 Department of Crop Protection and Environmental Biology (CPEB), University of Ibadan, Nigeria; and 2 Virology and Molecular 

Diagnostics Unit (VMD), International Institute of Tropical Agriculture, Ibadan, Nigeria. adedapo.adediji@yahoo.com 

In order to ascertain the presence, incidence, and distribution of Citrus tristeza virus (CTV), extensive 

surveys were conducted in citrus growing areas of South-Western Nigeria during 2011-12. A total of 565 

citrus trees were sampled in three states. Leaf samples from citrus trees were collected and symptom 

severity was recorded. Symptoms observed included stem pitting, stunting, vein clearing and leaf curling. 

Molecular analyses by RT-PCR of nucleic acid extracted from diseased samples were used to detect virus 

presence using CTV-specific primers PIN1 and PIN2 directed to the conserved 3’ untranslated region. 

Results show the presence of CTV in all the three states surveyed while symptom severity differed from one 

location to another. Disease incidence varied from 85.2% in Oyo State to 48.4% in Ogun State. Citrus trees 

were infected regardless of scion-rootstock combinations and were detected in sweet orange (87.0%), 

tangerine (77.6%), grapefruit (73.8%) and lemon (69.5%). This is the first report of molecular detection of 

CTV in Nigeria. 

S14P03 

A rapid procedure to evaluate the protecting ability of Citrus tristeza virus mild isolates against 

severe isolates 

Ruiz Ruiz S. 1 , Navarro-López J. 2 , Moreno P. 2 , and Ambrós S. 2 

1 Instituto de Biología Molecular y Celular de Plantas (IBMCP), Valencia, Spain; and 2 Instituto Valenciano de Investigaciones Agrarias 

(IVIA), Centro de Protección Vegetal y Biotecnología, Moncada, Valencia, Spain. suruirui@upvnet.upv.es 

Measures to control damage caused by severe stem pitting isolates (SP) of Citrus tristeza virus (CTV) include 

selective eradication and cross protection with mild strains (MS). Implementation of these measures needs 

sensitive and specific methods to discriminate between SP and MS variants in the viral populations. We 

developed a quantitative real-time RT-PCR method using TaqMan locked nucleic acid (LNA) probes that 

enabled quantification of SP and MS variants in natural CTV populations. Here we used this method to 

monitor the evolution of the CTV population in Pineapple sweet orange plants pre-inoculated with a MS 

(T32) or a SP (T318) isolate, and then challenge-inoculated with budsticks infected with a SP or a MS 

isolate, respectively. While control plants singly inoculated with T32 or T318 only contained the cognate 

CTV variant in successive flushes, the plants doubly inoculated contained both types of sequence variants 

in tissues derived from either the receptor plant or the inoculum budstick, with no strain impairing systemic 


invasion by the other. The relative amount of T32 and T318 variants in the viral population of co-infected 

plants varied between flushes although T32 appears to be prevalent. The co-infected plants showed stem 

pitting symptoms similar to those of plants inoculated only with T318, whereas control plants inoculated 

only with T32 or non-inoculated remained symptomless. This procedure enables rapid evaluation of MS for 

cross protecting ability. 

S14P04 

Expression of different proteins in sweet orange induced by severe and mild Citrus tristeza virus 

(CTV) isolates 

Yang F.Y., Li Z.A., Zhou C.Y., and Zhou Y. 

Citrus Research Institute of CAAS (CRIC), National Citrus Engineering Research Center, P.R. China. yfangyun@163.com 

A comparative proteomics analysis was performed to identify the molecular response of sweet orange 

plants to the infection of severe and mild Citrus tristeza virus (CTV) isolates. Two-dimensional difference 

gel electrophoresis (2D-DIGE) was adopted to compare and evaluate total proteins extracted from leaves. A 

total of 82 protein spots showed differences in their relative abundance with a one-way analysis of variance 

[1-ANOVA] value of ≤0.001. Fifty differentially expressed protein spots were identified by MALDI-TOF/MS, 

and searched in protein databases. According to the putative functions, the identified proteins were classified 

into four groups such as carbohydrate metabolism, energy metabolism, nucleotide metabolism, and folding, 

sorting and degradation. The identified proteins were involved in various physiological responses such as 

gluconeogenesis, citrate cycle, ascorbate and aldarate metabolism, glyoxylate and dicarboxylate metabolism, 

carbon fixation in photosynthetic organisms, purine metabolism, glutathione metabolism, protein processing 

in endoplasmic reticulum and RNA degradation. The results showed that the phospho-D-glycerate hydrolase, 

iron superoxide dismutase, xyloglucan endotransglycosylase, adenylate kinase and major latex-like protein 

were likely associated to severe CTV pathogenesis, whereas NADP-isocitrate dehydrogenase, heat-shock 

protein, miraculin-like protein, thioredoxin, L-ascorbate peroxidase, enolase, isocitrate dehydrogenase and 

HSP20 family protein might be related to mild CTV effect. 

S14P05 

Screening of Citrus tristeza virus in sweet oranges and limes of the Colombian Citrus Collection 

(Corpoica - Meta) 

Guzmán-Barney M.M. 1 , Rodríguez P. 1 , Ordúz J. 2 , and Martínez J. 1 

1Universidad Nacional de Colombia - Instituto de Biotecnologia (UN-IBUN), Bogotá, D.C., Colombia; and 2Corporación Colombiana de 

Investigación Agropecuaria (Corpoica), Meta, Colombia. mmguzmanb@unal.edu.co 

Citrus tristeza virus (CTV), a phloem-limited virus with a ssRNA genome, is transmitted by aphids including 

Toxoptera citricida. The main symptoms incited by CTV are Quick Decline (QD) and Stem Pitting (SP). CTV 

is deleterious for citriculture and endemic in Colombia. Being important to distinguish CTV variants for 

disease management, we characterized CTV isolates infecting sweet oranges (Citrus sinensis, SO) and Tahiti 

limes (C. latifolia, TL) grafted on different rootstocks. Three groups of ten year old trees were studied: 10 

SO and 22 TL grafted on Cleopatra mandarin and 60 TL grafted on different rootstocks (Sunki x English, 

Sunki x Jacobsen, Kryder, volkamer lemon, Cleopatra mandarin, Rubidoux and Pomeroy trifoliate orange 

and Carrizo citrange). Antibody MCA13 and 8 CTV-specific reported probes were used. Dried tissue infected 

with CTV isolates B272, B274 (mild), B128 (SP), T385 (mild) and T346 (common) were used as control. 

Probes labeled with Dig-UTP were: ABC (CTV) B3A (severe SP Madeira) B1 (T36 QD strain) B2 (K strain) 

B4 (T3 SP-QD, Florida) B5 (severe SP SO B249, Venezuela) B8 (mild) III (VT Israel-28C). MCA13 positive 

reactions were observed with all trees suggesting severe isolate infections. Probes B3A, B5 and B1, yielded 

optical density values (OD>1). The probes B1, CTV III and mild B8 hybridized showing OD

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S14P06 

Molecular diversity of Citrus tristeza virus isolates collected over the past 50 years and 

maintained in planta collections in California 

Wang J.W. 1 , Bozan O.B. 2 , Kwon S.J. 1 , Rucker T.R. 1 , Thomas C.T. 3 , Yokomi R.K. 4 , Lee R.F. 5 , Folimonova S. 6 , and Vidalakis G. 1 

1University of California, Riverside (UCR), Plant Pathology and Microbiology, U.S.A.; 2University Of Çukurova (CU), Department of 

Plant Protection, Turkey; 3Central California Tristeza Eradication Agency (CCTEA), U.S.A.; 4United States Department of Agriculture- 

Agricultural Research Service (USDA-ARS), U.S.A.; 5United States Department of Agriculture-Agricultural Research Service, National 

Clonal Germplasm Repository for Citrus and Dates (USDA-ARS, NCGRCD), U.S.A.; and 6University of Florida/Citrus Research and 

Education Center (CREC), Plant Protection, U.S.A. vidalg@ucr.edu 

Tristeza, caused by Citrus tristeza virus (CTV), is a serious citrus disease worldwide. Because of the economic 

damage that severe isolates of CTV can induce on fruit production and quality, CTV has been a regulated 

pathogen in California. CTV has been eliminated from all citrus germplasm sources and infected field trees 

have been eradicated in quarantine zones. Until recently, a low rate of natural spread and the eradication 

program limited CTV genetic diversity in Central California to primarily T30-like genotypes. These isolates 

cause no significant damage on citrus grafted on CTV resistant or tolerant rootstocks, under California 

conditions. Recently, severe non-T30 genotypes of CTV have been detected in California orchards and tristeza 

has become a re-emerging disease with potential to cause economic damage. To elucidate the origin of 

recent CTV isolates, genetic diversity of more than 300 CTV isolates collected from 1960-2010 across all 

major citrus-growing regions in California and maintained in planta collections at the University of California, 

Riverside, Citrus Clonal Protection Program and the Central California Tristeza Eradication Agency at Tulare 

were evaluated. These collections provided a valuable historical sample of past CTV occurrence in California. 

Full-length sequencing of the major coat protein gene and/or PCR amplification with molecular markers 

targeting different CTV genome regions showed T30 genotypes were abundant in California but a few T36- 

, VT- and B165-like strains were also present at some point in time. Several nonstandard CTV genotypes 

were also identified. The genetic diversity documented in this study provides a basis for development of CTV 

management strategies such as cross-protection and provides insight into interactions amongst CTV isolates 

as well as interactions that might occur with the introduction of virulent CTV isolates. 

S14P07 

Implication of Toxoptera citricida on temporal and spatial dispersion of Citrus tristeza virus in 

Southern Mexico 

Domínguez Monge S. 1 , Mora Aguilera G. 1 , Loeza Kuk E. 2 , Flores Sánchez J.L. 1 , Acevedo Sánchez G. 1 , and Robles García P. 3 

1 Colegio de Postgraduados-Campus Montecillo (COLPOS), Fitopatología, México; 2 Campo Experimental Mococha, Yucatán México 

(INIFAP), Fitopatología, México; and 3 Dirección General de Sanidad Vegetal (DGSV), Dirección de Protección Fitosanitaria, México. 

dominguez.santiago@colpos.mx 

At 11 years after Toxoptera citricida (TC) introduction into Mexico, this study was carried out to evaluate the 

epidemiological impact of TC on spreading Citrus tristeza virus (CTV) in the Yucatán Peninsula. Data from 1999- 

2008 were integrated with disease and vector assessments from 2010-2011 in 34 orchards from Yucatán, 

Campeche and Quintana Roo. Citrus variety, historical positive trees, age, planting density, rootstock, irrigation 

and symptom intensity were evaluated per orchard. TC adults were collected from 4 flushes of 10 trees/ 

orchard from January to March 2011. Additionally, 7 orchards were examined for infection by analyzing 1672 

samples by tissue print-ELISA. TC was restricted to the spring period, mainly on sweet orange trees and it was 

most prevalent in Yucatán and Campeche (5922 and 8810 aphids/orchard/year, respectively) suggesting that 

TC establishment was restricted and it neither influenced the regional spreading of CTV nor the occurrence 

of stem pitting and decline. In 2008, at the Peninsula level the cumulative incidence was 0.00005% relative 

to the estimated population of trees in the Yucatán Peninsula with the highest number of positive trees 

in Yucatán (1791) and Campeche (1139). At the orchard level the incidence was 0.6-36%, Yucatán being 

more affected, with Weibull epidemic rates of 1/b=0.017-0.030, AUDPC=40-52, and final incidence of 27- 

36%, indicating that CTV spread continues. GIS risk maps were developed and validated with historical CTV 

dispersion using a multivariate index based on host and vector density and minimum temperature providing 

a tool for epidemiological surveillance. 


S14P08 

Population variation of Citrus tristeza virus 

Qing L. 1 , Ruan T. 1 , Xiong Y. 1 , Zhou Y. 2 , Song Z. 2 , Sun X.C. 1 , Li Z.A. 2 , and Zhou C.Y. 2 

1 Southwest University (SWU), College of Plant Protection, China; and 2 Chinese Academy of Agricultural Sciences (CAAS), Citrus 

Research Institute, China. qling@swu.edu.cn 

Using the specific primer pair P23f (5’-TAAGAGTCTGCGAGTTACGATG-3’) and P23r (5’-TCCGTCCACTTCAATCAG-3’), 

the p23 gene of severe (CT3 and CT14) and mild (CT11 and CT18) isolates of Citrus tristeza virus (CTV) from 

grapefruit (CT3 and CT18) and sweet orange (CT11 and CT14) were amplified by RT-PCR and cloned. Eighty 

six clones of this gene were chosen randomly for sequencing, which composed four CTV populations. 

Genetic structure and variability of these populations were analyzed. The results demonstrated that all CTV 

populations were heterogeneous, consisting of sequences that were not identical but closely related to the 

consensus sequence. The percentage of mutated clones (41.7%) and mutation frequency (8.8×10-4) of the 

CT11 population were highest among these four populations, whereas those of the CT3 population, with 

only 13.0% percent of mutated clones and 2.0×10-4 mutation frequency were lowest. The CT14 and CT18 

populations shared the same mutation frequency (5.0×10-4), but the percentage of mutated clones of CT14 

(26.7%) was lower than that of CT18 (33.3%). Comparison of the variability of CTV mild isolates in different 

hosts showed that the percentage of mutated clones and mutation frequency of CT18 from grapefruit were 

lower than those of CT11 from sweet orange. Similarly, the percentage of mutated clones and the mutation 

frequency of the severe isolate CT3 from grapefruit were lower than that of CT14 from sweet orange, 

suggesting that variability of CTV is higher in sweet orange than in grapefruit. The consensus nucleotide 

sequence of CT3 has the highest identity (97%) with CT18 and the lowest (89.7%) with CT14, whereas highest 

identity of CT11 (95.5%) is with CT14 and the lowest (91.4%) with CT18. Substitution and deletion mutations 

were detected in CTV populations with the dominant mutation type being base transition from G to A. 

S14P09 

Nucleotide sequence of three genes of Citrus tristeza virus from selected isolates in a program of 

preimmunization. 

Zanutto C.A., Müller G.W., Corazza M.J., and Nunes W.M.C. 

Universidade Estadual de Maringa (UEM), Nucleo de Pesquisa em Biotecnologia Aplicada, Brazil. william.nunes@pq.cnpq.br 

Two capsid proteins (p25 and p27) are required for the correct assembly of Citrus tristeza virus (CTV) virions 

and for cell-to-cell movement. Protein p25 is also a suppressor of post-transcriptional gene silencing, as also 

is the p23 protein. To further advance in the knowledge on CTV isolates present in the Paraná State, Brazil, 

variability of the p23, p25 and p27 genes of two CTV isolates was analyzed. The isolates chosen for this study 

were the mild isolate CS-1, selected as protecting isolate for preimmunization in the Paraná State, Brazil, 

and the severe isolate called Rolândia, that has caused severe symptoms in many orchards in the North of 

the State and has been used as control in this program. The p23, p25 and p27 products RT-PCR amplified 

from these isolates were cloned, and multiple clones for each gene and isolate were sequenced. From the 

Rolândia isolate, five haplotypes were obtained for the p23 gene, five for the p27 and seven for the p25 (out 

of 10 clones), which showed identity values ranging from 82.5 to 97.5%, 95.1 to 98 3% and 92.3% to 99.2%, 

respectively. From the CS-1 mild isolate four haplotypes of the p25 gene and three haplotypes of the p27 gene 

were obtained, which showed identity values ranging from 96.2 to 99.3% and 98.3 to 99.1%, respectively. 

S14P10 

A comparative study and vector transmissibility of relevant Citrus tristeza virus (CTV) populations 

from Italy indicates a risk for further epidemics 

Yahiaoui D. 1 , Djelouah K. 1 , D’Onghia A.M. 1 , and Catara A. 2 

1 CIHEAM-Mediterranean Agronomique Institute of Bari (CIHEAM-MAIB), Integrated Pest Management, Italy; and 2 Università degli 

Studi di Catania, Dipartimento di Science e Tecnologie Fitosanitarie (DISTEF), Italy. djelouah@iamb.it 

In Italy, Tristeza declining trees on sour orange rootstock trace back to 2002. A mild and a seedling yellows 

Citrus tristeza virus (CTV) population were the causes of heavy losses on Navelina and Tarocco sweet oranges 


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along the Ionian coast and the South-Eastern part of Sicily, respectively. For a better understanding of 

their genetic features and spread dynamics, representative CTV isolates from each variant were used for 

molecular characterization and transmission trials with local aphid biotypes. Sequencing of fragments over 

the replication-related 5’UTR, and the p20, p23, p25 and p18 genomic regions have been performed, in order 

to assess the genetic divergence between the two isolates and eventual alterations after aphid passage. The 

latter represents one of the most significant data in virus–vector interactions. High nucleotide identity was 

shown between the Apulian isolate and the Spanish mild T385 strain, and between the Sicilian isolate and 

the Spanish T318A strain, respectively. Moreover, only minor variations were observed in the p18 region of 

sub-isolates obtained after A. gossypii transmission of the Sicilian isolate. The two divergent CTV populations 

investigated in the present work appeared to be efficiently transmitted by A. gossypii (50% of efficiency) 

but they were prone to get altered after aphid transmission. These results may give indications on virus 

epidemiology in the Italian citrus scenario. 

S14P11 

Prevalence and Epidemiology of Citrus tristeza virus in Andalucía and Murcia regions 

of Spain 

Gorris M.T. 1 , Muñoz C. 2 , Cano A. 3 , Hermoso de Mendoza A. 1 , Martínez M.C. 1 , Hermosilla A. 3 , Fuentes F. 3 , Bertolini E. 1 , 

Collado C. 1 , López A. 4 , and Cambra M. 1 

1Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Moncada, Valencia, Spain; 

2Consejería de Agricultura y Pesca (Junta de Andalucía), Laboratorio de Sanidad Vegetal, Montequinto, Sevilla, Spain; 3Consejeria de 

Agricultura y Pesca (Región de Murcia), Laboratorio de Sanidad Vegetal, La Alberca, Murcia, Spain; and 4Universidad de Valencia (UV), 

Estadística e Investigación Operativa, Burjassot, Valencia, Spain. ebertoli@ivia.es 

The Spanish citrus industry is based on about 310,000 ha cultivation. Andalucía (74,000 ha), mainly growing 

sweet oranges, and Murcia (34,000 ha), growing lemons and mandarins, are the main citrus producing areas 

after Valencia. The spread of Citrus tristeza virus (CTV) was monitored by Tissue print-ELISA (Plant Print 

Diagnostics) since 1982 in Andalucía and since 1996 in Murcia to 2011 in different citrus orchards. Surveys in 

different municipalities of Andalucía suggest that the disease spreads slowly (i.e. CTV prevalence increased in 

a sweet orange orchard in Lora del Río/Sevilla from 0.25% in 1982 to 2.90% in 2011). In Alhama de Murcia CTV 

prevalence increased in a mandarin orchard from 1.00% in 1996 to 70.00% in 2011. The aphid species landing 

on the trees were monitored by the sticky shoot method during the same period. Toxoptera aurantii and Aphis 

spiraecola (inefficient CTV vector species) are predominant in both regions in contrast with Valencia where A. 

gossypii (efficient CTV vector) is the predominant aphid species. The different aphid species predominant in 

Andalucía-Murcia and in Valencia, could justify differences in the temporal spread of CTV among these areas: 

logistic model in Andalucía-Murcia versus Gompertz model in Valencia. The epidemiological data allowed 

specific recommendations to the growers in order to successfully reconvert the citrus industry (already done 

in almost 90% in both regions). 

S14P12 

Epidemiology of Citrus tristeza virus in experimental nursery blocks of citrus rootstock species 

in Spain 

Gorris M.T. 1 , Rodríguez A. 1 , Martínez C.M. 1 , Bertolini E. 1 , Collado C. 1 , Botella P. 2 , López A. 3 , and Cambra M. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Moncada, Valencia, Spain; 

2 Universidad CEU-Cardenal Herrera (CEU), Ciencias Físicas, Matemáticas y Computación, Alfara del Patriarca, Valencia, Spain; and 

3 Universidad de Valencia (UV), Estadística e Investigación Operativa, Burjassot, Valencia, Spain. mcambra@ivia.es 

The susceptibility to Citrus tristeza virus (CTV) natural infection of the most commonly used citrus rootstocks 

in Spain (Carrizo citrange, Cleopatra mandarin, Citrus volkameriana, C. macrophylla, sour orange and 

citrumelo), was studied by Tissue print-ELISA (Plant Print Diagnostics) in the Peñíscola area. The most 

susceptible rootstock species was C. macrophylla followed by C. volkameriana. Cleopatra mandarin showed 

an intermediate susceptibility and Carrizo citrange and sour orange very low susceptibility. Citrumelo resulted 

non-susceptible. Three experimental blocks of 10,000 plants each of C. macrophylla, Cleopatra mandarin and 

Carrizo citrange were established to elucidate the reasons of different susceptibility to natural CTV-infection. 


Spatial analysis showed that small clusters of infected plants were only detected in the C. macrophylla block 

(4.8% CTV prevalence). CTV prevalence was 1.9% in Cleopatra and 0.7% in citrange experimental nursery 

blocks. Aphid species visiting rootstock seedlings were monitored by the sticky shoot method. Aphis gossyppi 

was the predominant vector species visiting nursery plants followed by A. spiraecola. May was the month 

with highest aphid populations and C. macrophylla was the most visited citrus rootstock species (about 1,700 

A. gossypii individuals visited each plant). This fact justifies the relatively high CTV prevalence found in this 

species. Seedlings of the most susceptible citrus species must be permanently protected against natural CTV 

infection. In addition, individual testing of nursery plants by Tissue print-ELISA could guarantee the CTV-free 

status in certified citrus plants. 

S14P13 

Monitoring Citrus tristeza virus (CTV) and characterization of local isolates in Algeria 

Larbi D. 1 , Belkahla H. 1 , Djelouah K. 2 , and D’Onghia A.M. 2 

1Univesity Saad Dahleb Soumaa Blida (UniB), Agronomy, Algeria; and 2Mediterranean Agronomic Institute of Bari (MAIB), Integrated 

Pest Management, Italy. lardjamila@yahoo.fr 

During the period 2009-2012, the main Algerian citrus growing areas located in Mitidja region were 

surveyed to assess the presence of Citrus tristeza virus (CTV). The main citrus varieties from ten selected 

sites were sampled and serologically analyzed. The hierarchical sampling method was carried out in each 

selected grove, with flowers, explants, and leaves being collected and analyzed by Direct Tissue Blot 

Immunoassay (DTBIA) using the commercial kit from Plantprint (Valencia, Spain). Among the 1903 samples 

tested, 468 (25.16%) CTV-infected trees were identified. The highest CTV infection rate was on common 

mandarin (70%), followed by Thomson navel orange and Washington navel orange, with infection rates 

of 46% and 8% respectively, whereas lower CTV prevalence was found in satsuma, Taroco, lemon and 

clementine (6%). Clear Quick Decline associated to the citrus tristeza disease were observed in some trees 

during the survey. A few samples that were CTV positive by DTBIA were also positive by biological indexing 

on Mexican lime (Citrus aurantifolia) and immunocapture-reverse transcription-PCR. SSCP analysis and 

subsequent sequencing of the coat protein gene from five Algerian CTV isolates showed 99% identity with 

the mild T30 CTV reference isolate. 

S14P14 

Evaluation of the sampling method of Citrus tristeza virus (CTV) in Apulia region, Italy 

D’Onghia A.M., Al Naasan Y., Santoro F., Figorito B., and Gualano S. 

Centre International de Hautes Etudes Agronomiques Méditerranéennes/Mediterranean Agronomic Institute of Bari (CIHEAM/MAIB), 

Integrated Pest Management, Italy. donghia@iamb.it 

Citrus Tristeza is the most destructive virus disease of citrus worldwide, mainly inducing decline of trees 

grafted onto the sour orange rootstock. The causal agent, Citrus tristeza virus (CTV), is widely present in the 

Mediterranean basin where it is efficiently transmitted by several aphid species, mainly by Aphis gossypii. 

Spain and Israel were forced to cope with this disease long time ago, whereas disease outbreaks in Italy, 

Greece and Morocco were reported in the last years. In Apulia region, Southern Italy, CTV monitoring and 

eradication programs are totally dependent on assessing the disease incidence in citrus groves, and according 

to the Apulian phytosanitary regulation the whole infected plot must be removed when a threshold of 30% 

CTV incidence is exceeded. The CTV monitoring programs adopted in Apulia have been implemented using 

systematic sampling method fundamentally based on sample group testing. This method differs from the 

Gottwald’s hierarchical sampling (HS) method by testing all sampled trees individually using DTBIA instead 

of testing the groups by ELISA. A detailed comparison between the Gottwald’s HS method and the one 

adopted in Apulia region is presented. The adopted sampling method was evaluated in 15 commercial groves 

with different infection rates. Also, we evaluated the estimation errors for the two sampling methods using 

statistical simulation tools. The results showed no difference between them. 


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S14P15 

Integrated Citrus Tristeza Virus complex management in Sicily 

Tumminelli R., Rotolo M.C., Saraceno F., Patti M.R., Saitta R., Conti F., Fisicaro R., Cavallaro A., Cavallaro G., Cutuli A., Greco 

G., Di Natale A., Garozzo M., Gullotta S., Privitera S., Quattrocchi S., Ricca G., Bertolami E., Calderone G., Maimone F., 

Schillaci G., Trifiletti A., Corno G., Bono G., Federico R., Lo Grasso F., Vicari M., Lo Presti P., Truncali S., Sicilia L., Giacalone 

A., Adragna V., Vecchio S., Filiddani R., Fascetto G.T., Marano G., Spadafora A., D’Anna R., Carta Cerella D., and Sinatra V. 

Servizio Fitosanitario Regionale Siciliano (SFR SICILY), Quarantine and Crop Protection Service, Italy. 

riccardo.tumminelli@regione.sicilia.it 

Citrus tristeza virus (CTV) complex causes one of the most destructive diseases of citrus in the world. In 

Sicily (Italy) it was first detected in 1956. Recently the virus has spread widely in citrus areas where trees 

are grown almost exclusively on sour orange, a very susceptible rootstock. In 2012, in Sicily, a European 

Union aid (12 million euros) was issued for the management of this complex. In the period 2008-12, in the 

framework of the official controls, monitoring was carried out in Sicily for the detection of CTV in citrus 

trees cultivated in nursery and field conditions. Aphids were also surveyed in order to exclude the presence 

of Toxoptera citricidus, detected in 2005 in the North-Western area of the Iberian Peninsula. This aphid is 

known as a very efficient vector of CTV. In the survey period nursery trees and mature orchards were checked 

utilizing DAS-ELISA test, and nursery trees were sampled for the identification of aphid species present on 

new shouts. A protected foundation block for budwood production was indexed, but CTV was never detected. 

The quarantine aphid T. citricidus was not observed. In spring and fall samples the presence of Aphis gossypii, 

A. spiraecola and T. aurantii was recorded in decreasing frequency order. 

S14P16 

Biological and molecular characterization of a Citrus tristeza virus isolate inducing seedling 

yellows and stem pitting in Hunan province, China 

Licciardello G. 1 , Russo M. 1 , Daden M. 2 , Dai S. 3 , Xiao C. 3 , Deng Z. 3 , and Catara A. 1 

1 Parco Scientifico e Tecnologico della Sicilia (PSTS), Italy; 2 International Plant Analysis and Diagnostics S.r.l. (IPADLAB), Italy; and 

3 National Center for Citrus Improvement, Hunan, China. acatara@pstsicilia.it 

Although Citrus tristeza virus (CTV) has been present in China for a long time, symptoms of decline are not 

apparent since the rootstocks commonly used are tolerant or immune. Nevertheless, recently the disease has 

become a problem in many provinces, including Hunan, with dwarfing, short internodes, leaf curl and stem 

pitting associated with small fruits and poor yield. Hence characterization of the genetic structure of the virus 

population in the province has been undertaken. Here we report biological and molecular characterization 

of a severe isolate inducing symptoms of seedling yellows and stem pitting on Mexican lime, sour orange, 

grapefruit and sweet orange. The CE-SSCP profiles of genes p18, p25, p20, p23 and p27 revealed a complex 

pattern with multiple peaks, suggesting the presence of mixed infections. Indeed, after molecular cloning of 

the coat protein gene, three different CE-SSCP profiles were obtained with relative frequencies of 10% (profile 

A), 70% (profile B) and 20% (profile C). Phylogenetic analyses showed that the major and minor variants 

clustered with isolates from Thailand, the Indian decline Kpg3 and the Hawaiian isolates HA18-9 and HA16-5. 

The third sequence variant grouped with severe seedling yellows and stem pitting isolates (VT, SY568, T318 

and NUagA). Analysis with multiple molecular markers (MMM) showed the presence of T36-, VT- and T30-like 

genotypes, differing from other isolates collected during the survey. 

S14P17 

Evaluation of productive and physiological parameters of Tarocco orange infected by a severe 

isolate of Citrus tristeza virus. 

Sorrentino G. 1 , Guardo M. 1 , Russo M.P. 1 , Davino S. 2 , and Caruso A. 1 

1 CRA - Centro di Ricerca per l’Agrumicoltura e le Colture Mediterranee (CRA-ACM), Italy; and 2 University of Palermo (DEMETRA), Italy. 

guido.sorrentino@entecra.it 

In this paper the effect of Citrus tristeza virus (CTV) on yield, fruit quality and chlorophyll content was 

investigated on a commercial field growing 30-yr-old Tarocco sweet orange grafted on sour orange. In 2002 

32% of the trees were infected with a severe CTV isolate (CTV-DS2), easily transmitted by aphids. Analysis 


was carried out for five years on groups of 50 plants showing different degrees of decline: severe decline (1), 

initial decline symptoms (2), symptomless infection (3) and CTV free (4). On each tree, fruit yield, fruit size, 

total soluble solids (T), acidity (A), T/A ratio, peel thickness, flesh and juice colour, and leaf chlorophyll content 

as estimated by SPAD 502 plus Konica Minolta, were measured. Simple variance and discriminant analysis 

showed that all parameters were influenced by the infection level. We postulated that SPAD index can be 

considered a first indicator to discriminate between healthy and CTV infected trees in well managed farms. 

S14P18 

Eradicating Citrus tristeza virus and Citrus tatter leaf virus from double infected citrus plants 

Qiao Q., and Jiang J. 

Huazhong Agricultural University (HZAU), College of the Department of Horticulture and Forestry, China. jiangling@mail.hzau.edu.cn 

Because of their long-term agamogenesis in the production process, citrus species are often susceptible 

to one or several viruses such as Citrus tatter leaf virus (CTLV) and Citrus tristeza virus (CTV), which are key 

limiting factors for commercial citrus development. This study focuses on finding rapid and efficient methods 

for eliminating these two virus pathogens of infected citrus plants. Botanical agents A extracted from Isatis 

indigotica and B extracted from Scutellaria baicalensis were used in an experiment combined with traditional 

virus eliminating methods (shoot-tip grafting and thermotherapy). For shoot-tip grafting, the triangle method 

was implemented. Buds used were terminal buds with three leaf primordia and the rootstock used was Bingtang 

orange cultivated in dark for about 14 days. The heat treatment was performed as follows, first we adopted 

constant temperature (37 ºC) for 50 days, then 40 ºC and 10 h light and 25 ºC and 14 h dark for 30 days. Heat 

treatment and phytotherapy were operated at the same time. The reverse transcriptase and PCR amplification 

(RT-PCR) was used to test whether plants subjected to these treatment were virus-free. Results showed that 

adopting the agents from Chinese medicine combined with the heat treatment in which the highest temperature 

was 40ºC during the day (6 h/ d) and the lowest temperature was 25ºC in the evening to keep the vegetation for 

fifty days in the greenhouse provided the best results. This protocol allowed to completely eliminate CTV and 

CTLV from double infected plants. Furthermore, the combination of shoot-tip grafting and the antiviral Chinese 

medical treatment allowed 85.7% eradication of both viruses from infected plants. 

S14P19 

Construction of an infectious cDNA clone of Citrus tatter leaf virus from an infected sweet orange 

Song Z., Zhou C.Y., Liu K.H., and Li Z.A. 

Chinese Academy of Agricultural Science, Citrus Research Institute, China. songzhen168@163.com 

A full-length cDNA clone of Citrus tatter leaf virus (CTLV-XHC) isolated from Citrus sinensis ‘Xinhuicheng’ was 

constructed after sequencing the virus. The complete genome sequence of CTLV-XHC was determined to be 

6,496 nucleotides in length, excluding the 3’-terminal poly(A) tract, and contained two putative overlapping open 

reading frames (ORFs). ORF1 (positions 36-6351) encodes a potential polyprotein of 242 kDa. ORF2 (positions 

4787-5747) codes for a 36 kDa protein. Nucleotide sequence comparison showed 80.9% to 97.6% identity to 

other CTLV or Apple stem grooving virus (ASGV) sequences. The cDNA clone of this CTLV genomic RNA was fused 

to a binary vector (pCAMBIA1301) containing the Cauliflower mosaic virus 35S RNA promoter and the nopaline 

synthase gene polyadenylation signal. Agro-inoculation of this plasmid to leaves of Chenopodium quinoa and 

Nicotiana benthamiana resulted in systemic infection, which was confirmed by RT-PCR and symptom expression. 

The potential use of the infectious clone as a vector for virus-induced gene silencing (VIGS) in citrus is discussed. 

S14P20 

The psorosis B syndrome in citrus is associated with a sequence variant of the Citrus psorosis 

virus RNA2 

Velázquez K., Alba L., Pina J.A., Navarro L., Moreno P., and Guerri J. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Moncada, Valencia, Spain. 

velazquez_kar@gva.es 

Psorosis disease of citrus is characterized by bark scaling in the stem and main branches of trees at least 10 

years old. Graft-inoculation of sweet orange seedlings in the greenhouse with non-scaled bark pieces from an 


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infected tree incites the psorosis A syndrome (PsA), including a shock reaction of the first flush and transient 

chlorotic flecking in young leaves of the following flushes, whereas inoculation with scaled bark pieces incites 

the psorosis B syndrome (PsB), that in addition to PsA includes gummy pustules in old leaves and branches. 

Psorosis disease is caused by Citrus psorosis virus (CPsV), an ophiovirus with three negative-stranded genomic 

RNAs. While comparison of RNA1 or RNA3 fragments by single-strand conformation polymorphism (SSCP) 

analysis did not show any difference between plants affected by the PsA or the PsB syndromes, a fragment of 

RNA2 enabled discriminating both syndromes by their SSCP profile. Some plants inoculated with scaled bark 

did not show PsB at 6 months post-inoculation (mpi) and their RNA2 gave a PsA-type SSCP profile. At 12 mpi 

these plants showed pustules in the trunk but not in the leaves. SSCP analysis of RNA2 showed only PsA-type 

variants in the leaves, whereas the pustuled trunk areas contained both PsA and PsB variants, the latter being 

predominant. These results suggest that psorosis-affected trees contain the two sequence variants and that 

the PsB variant is associated with pustules and tends to accumulate in the trunk bark. 

S14P21 

Sensitivity to Citrus psorosis virus of species and hybrids of the genus Citrus and relatives 

Velázquez K., Alba L., Zarza O., Vives M.C., Pina J.A., Juárez J., Navarro L., Moreno P., and Guerri J. 


velazquez_kar@gva.es 

Citrus psorosis virus (CPsV), genus Ophiovirus, causes an important disease in many citrus growing regions. 

Virus damage can be controlled using resistant or tolerant cultivars, but sensitivity of many species and hybrids 

of Citrus and related genera is unknown. To find potential sources of CPsV resístance we first propagated 61 

species (or cultivars) and hybrids of Citrus and related genera [Citrus (37), Microcitrus (5), Fortunella (6), 

Eremocitrus (1), Pleiospermium (1), Atalantia (1), Severinia (1), Clausena (1), Poncirus (1) and hybrids (7)] on 

rough lemon seedlings inoculated with the CPsV isolate PB-143. Out of the 61 accessions tested 54 showed 

symptoms and positive ELISA reaction, 2 (M. inodora y F. hindsii) were symptomless but gave high ELISA values, 

suggesting tolerance to CPsV, 5 (C. depresa, C. reshni, C. excavata, Carrizo citrange (CC) and citrumelo CPB 

4475) showed symptoms in the first flush but negative ELISA reaction, and 1 (P. trifoliata) was ELISA negative 

and symptomless. We then examined infection by quantitative real time RT-PCR in C. reshni, P. trifoliata and 

CC seedlings inoculated with CPsV isolates P-121, PB-102 and PB-143. While P-121 was detected in all C. 

reshni, and CC, and in 75% of P. trifoliata plants, the other isolates infected only 32-82% (PB-143) or 20-91% 

(PB-102) of the inoculated plants. These three accessions showed necrosis around the inoculum patch that 

impaired or delayed infection, suggesting isolate-dependent partial resistance. 

S14P22 

Detection and quantitation of Citrus psorosis virus by real time RT-PCR 

Velázquez K., Alba L., Guerri J., Moreno P., Navarro L., and Vives M.C. 


cvives@ivia.es 

Citrus Psorosis, an important disease in many citrus growing regions, is caused by Citrus psorosis virus (CPsV), 

an ophiovirus transmitted through infected buds and naturally spread in areas of South America. The CPsV 

genome consists of three single-stranded, negative-sense RNAs. Psorosis has been diagnosed by biological 

indexing on indicator plants, and more recently by ELISA, tissue-print hybridization or RT-PCR. ELISA enables 

fast and specific detection of CPsV, albeit with low sensitivity, and the other procedures do not allow virus 

quantitation in different varieties, tissues and seasons. To develop a highly sensitive and reliable technique 

for CPsV detection and quantitation we set up a real-time RT-PCR assay (qrt-RT-PCR) using SYBR Green and 

the CPsV RNA3 as target. This protocol enables detection of 1000 CPsV RNA copies in plant extracts with a 

linear response along a dynamic range of 7 log units of concentration. Sensitivity of CPsV detection by qrt-RT- 

PCR is much higher than with ELISA or conventional RT-PCR, and it enables detection of distinct viral isolates 

infecting field trees of different citrus species all year around. Maximum accumulation of CPsV was observed 

in young leaves and bark, but it was also detected in old bark and leaves. The lowest CPsV accumulation was 


detected in the main trunk and roots. The new assay is a valuable tool to screen for resistance and a major 

improvement for CPsV detection in sanitation, quarantine and certification programs. 

S14P23 

Improvement in diagnosis for Citrus Psorosis in Argentina by qRT-PCR 

de Francesco A. 1 , Reyes C.A. 1 , Costa N. 2 , and Garcia M.L. 1 

1 Instituto de Biotecnología y Biología Molecular (IBBM), La Plata, Buenos Aires, Argentina; 2 Estación Experimental Agropecuaria 

Concordia (INTA EEA Concordia), Entre Rios, Argentina. agustinadefrancesco@hotmail.com 

Citrus is one of the most important crops in Argentina, a leading export country of oranges and lemons. 

Several diseases affect citrus in Argentina, among them Psorosis is still a serious and widespread viral disease, 

making trees less productive and causing economic losses. In the field, symptoms are observed mainly in 

sweet orange, showing bark scaling restricted to the main trunk and limbs, and chlorotic flecks and spots 

in young leaves. Citrus psorosis virus (CPsV), the casual agent of the disease is the type member of genus 

Ophiovirus, family Ophioviridae. Virus particles have filamentous circular morphology, and its genome has 

three negative single-stranded RNAs encapsidated with a coat protein. CPsV can be detected by TAS-ELISA 

using polyclonal and monoclonal antibodies and by RT-PCR with specific primers. These procedures are 

faster and more reliable than biological indexing. Real-time RT-PCR (qRT-PCR) using Taqman probes has been 

applied successfully for detection of Mexican and European CPsV isolates. In this work, we applied a new qRT- 

PCR using SYBR Green and specific primers designed in a region of the coat protein gene that is conserved in 

Argentinian isolates in order to improve disease control in our country. We compared our results of qRT-PCR 

with TAS-ELISA and RT-PCR applied in field samples and will discuss reliability of these methods. 

S14P24 

Cloning and sequence analysis of the large coat protein of Satsuma dwarf virus Fengjie isolate 

Sun X.C. 1 , Qing L. 1 , Yang F.Y. 2 , and Zhou C.Y. 2 

1 Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing, China; and 

2 National Center of Citrus Engineering and Technology Research, Citrus Research Institute of Chinese Academy of Agricultural 

Sciences, Chongqing, China. xianchaosun@gmail.com 

Satsuma dwarf virus (SDV) mainly infects satsuma mandarins, causing serious Satsuma Dwarf disease. In 

China, Satsuma Dwarf was found in Fengjie of Chongqing, Wu city of Jiangsu province and Huangyan of 

Zhejiang province since satsuma mandarins were introduced from Japan in the 1980s. However, it is unclear 

whether the virus in China and the S-58 isolate reported from Japan are the same strain or whether SDV has 

evolved and become adapted to the new environment and hosts. To answer this question, the large coat 

protein (CPL) gene of SDV isolated from Fengjie (SDV FJ) was amplified by RT-PCR and cloned into vector 

pGEM-T for sequencing. Sequence analysis showed that the SDV-FJ CPL gene had 1329 nt, encoding a protein 

of 443 amino acids. Comparison of this sequence with those of other viruses of the genus Sadwavirus showed 

high nucleotide and amino acid identity (98.1% and 98.6%) between SDV FJ and SDV S-58 from Japan. The 

SDV FJ CPL gene had 25 nucleotide differences with the SDV S-58 CPL, the most frequent being T and C 

transitions. Therefore, it is suggested that the SDV FJ and S-58 are the same strain of SDV. 

S14P25 

Characterization and incidence of Citrus leaf blotch virus (CLBV) in Southern Italy 

Guardo M., Sorrentino G., and Caruso A. 

CRA - Centro di Ricerca per l’Agrumicoltura e le Colture Mediterranee (CRA-ACM), Italy. guido.sorrentino@entecra.it 

Citrus leaf blotch virus (CLBV), the type species of the new genus Citrivirus of the family Flexiviridae, has 

been associated with a bud union disorder of Nagami kumquat and calamondin scions grafted on trifoliate 

rootstocks. After the first report in Italy in 2007, surveys to monitor CLBV incidence were carried out in 

nurseries, private collections and commercial citrus orchards with bud union disorder problems from Sicily 

and Calabria using biological indexing and RT-PCR. Each positive sample was analysed by Single-Strand 


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Conformation Polymorphism (SSCP) and samples with different electrophoretic pattern were cloned and their 

nucleotide sequence compared by CLUSTALW. The results confirmed the presence of CLBV in Italy and three 

new sequences were found and deposited in GenBank. No positive samples were found in varieties other 

than Nagami kumquat, with 80% of infected trees, or calamondin, with 31% infected trees. This low CLBV 

incidence in symptomatic calamondin trees could be due to a low virus titer in calamondin, or to bud union 

crease being caused a different pathogen or by the interaction between biotic or abiotic factors. 

S14P26 

Citrus leaf blotch virus (CLBV) invades meristematic regions in Nicotiana benthamiana and citrus 

Agüero J., Vives M.C., Velázquez K., Ruiz-Ruiz S., Juárez J., Navarro L., Moreno P., and Guerri J. 


jguerri@ivia.es 

Systemic infection by plant viruses involves long distance movement through the phloem sieve tubes. 

Since the vascular system is not developed in the vicinity of apical meristems, most viruses are unable to 

reach this region, a phenomenon that has been exploited to recover virus-free citrus plants by shoot-tip 

grafting in vitro. However, Citrus leaf blotch virus (CLBV) is difficult to eliminate by this method and seed 

transmission has been observed, suggesting that this virus does invade meristematic regions. To examine this 

hypothesis we monitored CLBV movement and accumulation using and infectious cDNA clone of the CLBV 

genome engineered to express the green fluorescent protein (GFP) gene. For this purpose, the promoter 

inducing transcription of the ORF2 subgenomic RNA was conveniently reduced and duplicated in the 3’ 

terminal untranslated region to obtain the infectious clone clbv3’pr-GFP. This extra gene does not affect virus 

functionality and produces GFP fluorescence in infected cells. Nicotiana benthamiana plants agroinoculated 

with clbv3’pr-GFP showed fluorescence in all tissues including meristematic regions, but in citrus plants 

infected with CLBV-GFP fluorescence was not visible and GFP had to be detected by western blot analysis. In 

lime plants inoculated with Citrus tristeza virus (CTV), which cannot infect meristematic regions, CLBV or CLBV 

plus CTV, hybridization and real time RT-PCR allowed detection of CLBV, but not of CTV, in shoot tips less than 

0.2 mm long. 

S14P27 

Simultaneous detection of Citrus exocortis viroid and Hop stunt viroid in citrus plants by direct 

tissue-print duplex real-time RT-PCR 

Bertolini E. 1 , Martínez M.C. 1 , Serra P. 2 , Olmos A. 2 , Carbó C. 1 , Duran-Vila N. 1 , and Cambra M. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Moncada, Valencia, Spain; and 

2 Instituto de Biología Molecular y Celular de Plantas (IBMCP), Departamento de Biología del Estrés, Valencia, Spain. 

ebertoli@ivia.es 

Citrus exocortis viroid (CEVd) and Hop stunt viroid (HSVd) are the causal agents of Exocortis and Cachexia, 

respectively, the most important viroid diseases of citrus trees. Traditionally the detection of citrus viroids 

has been performed by biological indexing and/or biochemical and molecular techniques. Biological indexing 

(based on the use of indicator citrus species) is time consuming and requires expensive infrastructures. 

Biochemical and molecular methods (based on sPAGE, tissue print-hybridization after graft-inoculation on 

Citrus medica or conventional RT-PCR), require extract preparation, and they are generally laborious and 

time consuming and present risk of contamination, often resulting inconvenient for routine diagnostics. The 

usefulness of real-time RT-PCR to detect viroids has been reported previously. A real-time RT-PCR method 

using two newly designed primer pairs and TaqMan probes was successfully developed and patented for the 

simultaneous detection of both viroid species. A direct tissue-print sample preparation method was tested 

and used to analyze samples from different citrus species and in different seasons. Results confirm that the 

real-time RT-PCR approach is as reliable as biological indexing and more sensitive than conventional sPAGE 

and molecular hybridization, enabling reliable detection of both citrus viroids at any season with the same 

accuracy. The developed methods open new possibilities for sensitive, simple and accurate detection of citrus 

viroids. A kit for the detection of both citrus pathogens has been validated and its use could facilitate the 

sanitary controls required in certification programs. 


S14P28 

Setting up and evaluation of new primer sets for the detection of Spiroplasma citri the causal 

agent of citrus stubborn disease 

Abdel Fattah A., Valentini F., Frasheri D., D’Onghia A.M., and Djelouah K. 

CIHEAM-Mediterranean Agronomic Institute of Bari (CIHEAM-MAIB), Integrated Pest Management, Italy. djelouah@iamb.it 

Citrus Stubborn disease caused by Spiroplasma citri is a limiting factor for citrus production in countries with 

desert or semi arid conditions in the Mediterranean basin. Several polymerase chain reaction (PCR) assays has 

been previously developed but most of them lacked specificity or sensitivity for Spiroplasma citri detection. 

In order to develop a PCR assay specific and sensitive for detecting Mediterranean S. citri strains, three PCR 

primers were designed using the CLC Genomics Workbench 3.0 software, on the basis of repetitive sequences 

annotated “Hypothetical proteins”; a BLAST of the selected genes on the GeneBank showed no homology 

with genes of other organisms, spiroplasma plasmids, or known spiroplasma virus sequences. The primer 

pairs were annotated as ScX7, ScX8, and ScX9, their sensitivity was evaluated by PCR with serial dilutions of 

positive S. citri cultures and DNA extracted from S.citri infected plants, while the specificity was determined 

by PCR using the DNA extracted from cultures of other Spiroplasma species. Primer pairs were validated by 

comparing them with PCR primer pairs previously designed in other laboratories. The ScX7 (sequence derived 

from GenBank accession no. AM285309) was selected and used for further detection and surveys, owing to 

its high specificity and sensitivity when compared with all other primers. 

S14P29 

Biological characterization of a new lemon disease in China 

Chen H.M., Li Z.A., Zhou Y., Wang X.F., Tang K.Z., and Zhou C.Y. 

Citrus Research Institute, Chinese Academy of Agricultural Sciences (CRIC), National citrus Engineering Research Center, China. 

chenhongming_21@163.com 

In 2009, a new disease was discovered on Eureka lemon (Citrus limon) in an orchard of the Yunnan province. 

Nearly 10% of the plants were infected and showed yellow vein clearing of lateral veins, shrinking, watersoaked, 

and boat-shaped leaves. The symptoms were more severe on spring and autumn leaves than 

in summer leaves. This disease was transmitted by grafting from infected Eureka lemon to six lemon 

(Femminello, Fino, Villafranca, Verna, Kutdiken and Monachello) and two sour orange (Daidai and Morocco) 

varieties inducing similar symptoms. Variable symptoms were observed in other hosts ranging from severe 

yellowing and vein clearing on Dweet tangor, slight vein clearing on Tongshui 72-1 sweet orange and Marsh 

grapefruit, to no symptoms on Etrog citron, Mexican lime and Ponkan seedlings. Eight herbaceous plants 

were tested for mechanical transmission of the disease. While Vigna unguiculata and Capsicum frutescens 

showed conspicuous symptoms, Lycopersicum esculentum, Nicotiana benthamiana, Momordica charantia, 

Solanum melongena, Cucumis sativus and Sesamum indicum remained symptomless. Symptom expression 

was influenced by temperature, being intense between 18 and 24ºC but disappearing over 32ºC. Furthermore, 

crude extracts from young lemon leaves with yellow vein clearing were examined by transmission electron 

microscopy and showed filamentous virus particles measuring 13-15×400-1000 nm. Based on the above 

results, this disease is likely to result from Citrus yellow vein clearing virus (CYVCV). 

S14P30 

Virus and virus-like diseases of citrus in Oman 

Al-Sadi A.M. 1 , and Al-Harthi S.A. 2 

1 Sultan Qaboos University (SQU), Crop Sciences, Oman; and 2 Royal Court Affairs (RCA), Royal Gardens and Farms, Oman. 

alsadi@squ.edu.om 

A study was conducted to investigate virus and virus-like diseases of citrus in Oman. A survey over 2009 to 

2011 showed that Citrus tristeza virus (CTV), Citrus exocortis viroid (CEVd) and Hop stunt viroid (HSVd) are 

common in various regions of the country. These agents were detected in acid lime, sweet orange, sour 

orange, grapefruit, lemon and other citrus species. Stem pitting symptoms were found to be common for CTV 


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infected trees, while bark scaling was found to be common in some citrus cultivars infected by viroids. CTV, 

CEVd and HSVd were also detected in 45-79% of citrus seedlings imported from Syria, Lebanon, India, Jordan, 

Pakistan and Egypt. This provides evidence for circulation of CTV and citrus viroids via seedlings originating 

in these countries. Cloning and sequencing the CP gene of 6 isolates of CTV showed that the isolates have 

96-99% identity with representative isolates from other parts of the world. Phylogenetic analysis of the CTV 

isolates provided evidence that 4 isolates belong to CTV Group 4. However, 2 isolates formed a clade and were 

separated from all other CTV groups with 100% bootstrap support, which suggests that the two isolates from 

Oman constitute a new CTV phylogenetic group. Work is in progress to characterize phylogenetic relationship 

of citrus viroids from Oman with viroids from other parts of the world. 

S14P31 

Recent trends in diagnosis, characterization, and management of major virus and virus-like 

pathogens infecting citrus in India 

Ghosh D.K. 

Plant Virology Laboratory, NRC for Citrus, Nagpur (44000), Maharashtra, India. ghoshdk@hotmail.com 

The field of citrus virology has expanded in the past couple of decades due to the discovery of various virus 

and virus-like pathogens. The economic importance of these pathogens derives largely from their ability 

to cause systemic diseases and to persist in vegetative parts of the plants for as long as the trees remain 

alive. Hence losses are not confined to the season in which infection occurs, but continue as long as the 

infected plants are in culture. In India about sixteen such pathogens are reported to infect citrus plants among 

which Citrus tristeza virus (CTV), Indian citrus ringspot virus (ICRSV), Citrus yellow mosaic virus (CiMV), Citrus 

exocortis viroid (CEVd) and the Citrus Greening bacterium (HLB) are of major concern. Nagpur mandarin (Citrus 

reticulata), acid lime (Citrus aurantifolia) and mosambi (Citrus sinensis) are three important commercial crops 

in India and are infected by these pathogens resulting in gradual decline of citrus orchards. These pathogens 

can be diagnosed by conventional bio-diagnosis that has its own limitations. Today a multitude of PCR 

based techniques, viz. PCR, RT-PCR, IC-PCR, multiplex PCR etc., and protein based diagnosis using pathogen 

specific polyclonal and monoclonal antibodies are being used routinely for detection of these pathogens in 

citrus plant samples either as single or as mixed infections. Genomes of these pathogens have been cloned, 

sequenced and their phylogenetic relationships established. One important component for integrated disease 

management is to implement a citrus budwood certification program to provide planting material free from 

the major graft transmissible pathogens. Accordingly by using the standardized biological, serological, and 

molecular techniques, a citrus budwood certification program has been implemented in India to provide one 

million virus free citrus plants annually to the citrus growers. 

S14P32 

The citrus nursery tree certification program in Spain 

Pina J.A. 1 , Chomé P. 2 , Vives M.C. 3 , and Navarro L. 3 

1 Consellería de Agricultura, Pesca, Alimentación y Agua (CAPAA), Servicio de Sanidad Vegetal, Spain; 2 Ministerio de Agricultura, 

Alimentación y Medio Ambiente (MAGRAMA), Oficina Española de Variedades Vegetales, Spain; and 3 Instituto Valenciano de 

Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Moncada, Valencia, Spain. pina_jos@gva.es 

This program includes four blocks of trees: 1) The protected foundation block, that is maintained at IVIA and 

includes healthy plants recovered by shoot-tip grafting in vitro (STG) from local or foreign varieties. Plants 

are grown in containers inside insect-proof screenhouses. 2) Foundation blocks propagated with budwood 

from the protected foundation block and also grown inside screen- or greenhouses. They belong to individual 

nurseries or nursery groups. 3) Budwood increase blocks including plants propagated directly from foundation 

trees to increase the number of buds for propagation of certified trees. They are also maintained inside 

screen- or greenhouses at each nursery. 4) Certified nursery trees are propagated with budwood from the 

increase blocks. Certified trees are produced in the open field, in screenhouses or in greenhouses. Plants of 

each block are periodically indexed by different methodologies according to the regulations. The program 

is operating with this outline since 1979, when the first healthy plants recovered by STG were released to 


the nurseries, which started selling plants from this origin to growers in 1982. Since then, 103 varieties have 

been propagated with a total of 150 million certified plants, with sweet oranges representing 51% of the 

certified plants, clementines 27%, other mandarins 13%, lemons 6% and grapefruits 1%. Presently Carrizo 

citrange is used as rootstock for 59% of the nursery plants and Citrus macrophylla for 19%. A total of 40 

nurseries are presently operating and they are grouped in 7 foundation blocks. Under this program practically 

all the Spanish citrus industry has been renewed with healthy plants. Today, traditional graft transmissible 

pathogens do not pose any problem for our citrus industry. 

S14P33 

COST FA0806: Plant virus control employing RNA-based vaccines: A novel non-transgenic strategy 

Voloudakis A.E. 

Agricultural University of Athens (AUA), Dept. of Crop Science, Laboratory of Plant Breeding & Biometry, Greece. avoloud@aua.gr 

The current virus control methods are limited in number, efficacy and environmental suitability and current EU 

decisions restrict crop improvement strategies employing transgenic plants. To protect plants against existing 

and emerging virus diseases new methods are urgently needed. A very promising approach is the exploitation 

of RNA silencing, a natural, endogenous mechanism in plants that is a sequence-specific process leading to 

viral mRNA degradation. COST Action FA0806* (http://www.aua.gr/COSTFA0806) brings together several EU 

labs in order to develop suitable, efficient and cost-effective methods to induce anti-viral silencing in crops 

by the transient application of dsRNA, siRNAs and/or artificial small RNAs (collectively designated as “RNAbased 

vaccines”). These vaccines are produced either in vitro or in vivo in large quantities and are applied at 

laboratory or large scale employing specific delivery machinery. FA0806 is structured in three Working Groups 

(WGs), WG1: Development of novel non-transgenic strategies for plant virus control, WG2: Application of 

novel non-transgenic strategies for plant virus control, and WG3: Socio-economic evaluation of the impact of 

the novel application methods. In the frame of FA0806, Training Schools and Short Term Scientific Missions 

provide instruments for scientific exchange and training for early-stage and senior researchers alike. Currently, 

61 members from 28 COST countries and eight non-COST members, from Argentina, Australia, China, Mexico, 

New Zealand, Peru and South Africa participate in the Action. 

Contact information: Andreas Voloudakis (Action Chair): avoloud@aua.gr, Thomas Hohn (Action Vice Chair): 

thomas.hohn@fmi.ch, Maria Holeva (Action Secretary): m.holeva@bpi.gr. 

* COST 257/08 Memorandum of Understanding (2008). COST Action FA0806: Plant virus control employing 

RNA-based vaccines: a novel non-transgenic strategy. 

S14P34 

Performance of Maltaise demi-sanguine sweet orange on eight rootstocks inoculated with Citrus 

exocortis viroid (CEVd) and Cachexia viroid (CVIIb) 

Najar A. 1 , Homri N. 2 , Bouhlel R. 3 , Ben Mimoun M. 2 , and Duran-Vila N. 4 

1 Institut National de la Recherche Agronomique de Tunisie (INRAT), Plant protection, Tunisia; 2 Institut National Agronomique de Tunisie 

(INAT), Agronomie et Biotechnologie végétales, Tunisia; 3 INRAT, Horticulture, Tunisia; and 4 Instituto Valenciano de Investigaciones 

Agrarias (IVIA), Centro de Protección Vegetal and Biotecnología, Moncada, Valencia, Spain. asmanajara@yahoo.fr 

The performance of sweet orange “Maltaise demi-sanguine” infected with two isolates of Citrus exocortis 

viroid and with a cachexia inducing variant of Hop stunt viroid (citrus variant CVd-IIb) was evaluated on 

eight different rootstocks (sour orange, Carrizo citrange, Citrus volkameriana, Cleopatra mandarin, Swingle 

citrumelo 4447, Rangpur lime, C. macrophylla and Poncirus trifoliata) growing in an experimental field at 

INRAT station in El Gobba, Cap Bon region. The trees were planted in 2005 and yield and fruit quality and size 

were evaluated every year since 2007. The results obtained showed that HSVd (CVIIb) caused a significant 

reduction of canopy volume and fruit yield by 20 and 30 %, respectively, of trees grafted on C. macrophylla 

in comparison to non-inoculated trees. In addition, fruit quality was deteriorated. With citrumelo and C. 

volkameriana, canopy volume was decreased, while with sour orange and Cleopatra mandarin, tree volume 

was similar to non–inoculated trees. Similar yields were recorded for Maltaise demi-sanguine orange trees 


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grafted on C. volkameriana, sour orange and Cleopatra mandarin for the CVIIb inoculated trees and the noninoculated 

control. Yield of the Maltaise plants on citrumelo and Carrizo citrange infected with this viroid, was 

slightly lower without affecting the quality. Concerning Exocortis, data showed that with Poncirus trifoliata and 

Rangpur lime, CEVd infection affected tree height by 25% and 20%, respectively, compared to non-inoculated 

controls and reduced yield. For Maltaise grafted on Carrizo citrange and citrumelo infected with CEVd, yield 

was slightly decreased in comparison to control trees, but fruit quality was conserved. 

S14P35 

Biological and molecular detection of Citrus psorosis virus in the Northwest region of Morocco 

Achachi A.A., and Ibriz M. 

University Ibn Tofail, Faculty of Sciences, Kenitra (FSK), Department of Biology, Genetics and Biometry Laboratory, Morocco. 

asmaeachachi@yahoo.fr 

Psorosis is a very well known citrus disease causing important damage in many countries, particularly in 

Mediterranean countries. Based on reports of symptoms such as bark scaling on trunks and branches observed 

on sweet orange, mandarin and grapefruit trees, this disease is widely present in Morocco. To determine 

the presence of Citrus psorosis virus (CPsV), RT-PCR was performed on 24 samples from trees with psorosis 

symptoms from the Gharb, the Northwest region in Morocco. To assess CPsV association with psorosis disease 

in these uncharacterized field sources, samples were examined by biological indexing. Detection of CPsV by 

RT-PCR did not always correlate with observation of psorosis-like symptoms in field trees or in graft inoculated 

indicator plants, indicating that psorosis-like symptoms may be also induced by pathogens other than CPsV. 

These results show for the first time in Morocco that molecular tests reliably reflect Psorosis infection. 


Session 15 

FUNGAL DISEASES 

S15

S15O01 

The arrival of Citrus Black Spot (Guignardia citricarpa) in Florida and current research questions 

Dewdney M.M. 1 , Peres N.A. 2 , Schubert T.S. 3 , Mondal S.N. 1 , Hu J. 1 , and Hincapie Caputo M. 2 

1 Citrus Research and Education Center University of Florida (CREC UF), Plant Pathology, USA; 2 Gulf Coast Research and Education 

Center University of Florida (GCREC UF), Plant Pathology, USA; and 3 Department of Plant Industries, Florida Department of Agriculture 

and Consumer Services (DPI FDACS), Plant Pathology, USA. mmdewdney@ufl.edu 

In March 2010, the Florida Citrus Health Response Program discovered Citrus Black Spot (CBS) in juice blocks 

of ‘Valencia’ sweet orange in southwest Florida. In the last two years, the area where the disease has been 

found expanded from 14 km2 to 57 km2. In most of the affected blocks, disease incidence has been low, 

with one to a few symptomatic trees. In blocks where a few trees were symptomatic, most growers chose 

to remove trees but wide scale eradication was not a reasonable option. A successful eradication program 

would require the removal of all infected trees, yet the CBS life cycle, as presently understood, offers no 

protocol to ensure success. Upon discovery, quarantine measures were immediately applied to reduce 

further spread including covering fruit loads, safe debris disposal, fruit surface decontamination and fruit 

movement restrictions. Fungicide programs of copper and strobilurins were promptly initiated in affected 

groves. To enable better disease management in the humid subtropical climate of Florida, several research 

questions are being explored: 1) if methods of enhanced leaf litter decomposition reduce the number of 

Guignardia citricarpa pseudothecia in leaf litter; 2) the optimal wetting and temperature regimens to mature 

pseudothecia; and 3) the baseline sensitivity of G. citricarpa isolates to strobilurin fungicides for resistance 

management. Highlights from these projects will be presented. 

S15O02 

Predictive model for ascospore release of Guignardia citricarpa using climatological data 

Dummel D.M. 1 , Agostini J.P. 1 , and Moschini R. 2 

1 Instituto Nacional de Tecnología Agropecuaria (INTA), Plant Pathology. EEA Montecarlo, Misiones. Argentina; and 2 Instituto Nacional 

de Tecnología Agropecuaria (INTA), Instituto de Clima y Suelo, Castelar. Argentina. jpagostini@montecarlo.inta.gov.ar 

Citrus Black Spot, caused by Guignardia citricarpa, is a cosmetic disease that affects fruit appearance for 

export. A predictive model for ascospore release was developed using climatological data. Ascospore release 

was monitored in a ‘Valencia’ sweet orange grove in Misiones, Argentina on a weekly basis using a Burkard 

spore trap while climatological data was obtained from a Davis GroWeather station during the 2008/09 

season. The daily variables considered in the model were maximum and minimum temperature (°C), rain 

(mm), and days with more than 10 hours of leaf wetness (DMojt). Cumulative data were calculated for the 

7 days prior to the weekly ascospore count for 28 weeks and categorized as high, medium or low. Using 

stepwise regression of SAS, two models were defined for ascospore release. The first model had only one 

variable (LogitPrS= – 4,553 1,6015* DMojt) with a correlation coefficient of 67.9% whereas, the second model 

had one more variable included, viz. the number of days with temperatures between 20 and 29° C (DT) 

(LogitPrS= –6, 1318 1,8108*DMojt 3,4829*DT) which had a correlation coefficient of 82.1%. 

S15O03 

Assessment of retention and persistence of copper fungicides on sweet orange fruit and leaves 

using fluorometry and copper residue analyses 

Schutte G.C. 1 , Kotze C. 1 , Van Zyl J.G .2,3 , and Fourie P.H. 2,3 

1 Citrus Research International (CRI), Nelspruit, South Africa; 2 Department of Plant Pathology (US), Stellenbosch, South Africa; and 

3 Citrus Research International (CRI), Stellenbosch, South Africa. ts@cri.co.za 

High volumes of copper hydroxide, cuprous oxide and copper oxychloride were sprayed under natural conditions 

onto mature sweet orange trees to compare the retention on leaves and fruit over a period of 56 days by means 

of copper residue analyses and a spray deposition assessment protocol using fluorometry, photomacrography 

and digital image analyses. Rainfall and increase in fruit size were recorded to determine if it had an influence on 

weathering of copper residues. Applications with cuprous oxide retained significantly more copper residue and 


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fluorescent pigment in the first year, while copper hydroxide retained higher copper and pigment levels during 

the second year. Persistence of copper residues was similar and decreased at the same tempo during both 

seasons. The loss of copper residues was attributed to weathering, fruit growth and cumulative rainfall as these 

factors were inversely correlated with copper residue levels (Pearson’s r = -0.840, -0.722 and -0.733 respectively). 

A 76% and 90% correlation was observed between the copper residue analyzed and the quantitative fluorescent 

pigment measurements on mature leaves and fruit, respectively; showing that fruit is more reliable for 

fluorometry analyses and that this technique proved to be an effective tool for spray deposition and persistence 

assessment of copper fungicides. All the copper formulations tested at these registered rates at 35-day spray 

intervals were effective in controlling Citrus Black Spot caused by Guignardia citricarpa. 

S15O04 

Phyllosticta species associated with citrus diseases in China 

Wang X.H., Chen G.Q., Huang F., and Li H.Y. 

Wang Xinghong (X.H.), the Institute of Biotechnology, Zhejiang University, China. rm12407@hotmail.com 

A total of 496 Phyllosticta strains were obtained from mandarins (Citrus reticulata), pomeloes (C. maxima), 

sweet oranges (C. sinensis) and lemons (C. limon) in the main citrus producing regions across China, and 74 

strains were selected for phylogenetic analysis. Analyses inferred from the sequences of internal transcribed 

spacer region (ITS1, 5.8S nrDNA and ITS2), partial translation elongation factor 1-alpha (TEF1) and partial actin 

gene (ACT), showed these representative Phyllosticta isolates clustered in four distinct clades corresponding 

to three known, and one undescribed species, which was named as Phyllosticta citrichinaensis in this paper. 

P. citrichinaensis was obtained from leaves and fruits of all four citrus species, causing minor damage with 

irregular spots or freckles. P. citriasiana, associated with Tan Spot of pomeloes, was isolated only from this 

host, but never from lemons, mandarins and sweet oranges. P. citricarpa, the causal agent of Citrus Black Spot 

and presently subjected to phytosanitary regulations in the EU and USA, was isolated from lemons, mandarins 

and sweet oranges, but never from pomeloes. The isolates of P. citricarpa clustered in two subclades, one 

from mandarins, the other from sweet oranges and lemons. P. capitalensis was isolated from all four citrus 

species as an endophyte, causing false melanose, or occurred together with P. citricarpa or P. citriasiana. 

Morphological, cultural and biochemical characters were consistent with the results of phylogenetic analysis. 

In addition, a specific primer pair Pca8/ITS4 was and selected, and its corresponding PCR procedure was 

developed for the detection of P. citriasiana in this study. 

S15O05 

Development of an agrotransformation gene-silencing-system for Phyllosticta citricarpa and its 

use in functional analysis of the pathogenic genes 

Goulin E.H. 1 , Petters D.A.L. 1 , Figueiredo J.A.G. 1 , Senkiv C.C. 1 , Silva JR.G.J. 2 , Kava-Cordeiro V. 1 , Galli-Terasawa L.V. 1 , Peña 

L. 3 , and Glienke C. 1 

1 Federal University of Paraná (UFPR), Genetics, Brazil; 2 Fundação de Amparo a Citricultura do Estado de São Paulo (Fundecitrus), 

Brazil; and 3 Instituto Valenciano de Investigaciones Agrarias (IVIA), Spain. eduardo.goulin@gmail.com 

The genetics transformation by Agrobacterium tumefaciens is a widely tool to genetic modify of a lot of 

organisms, including phytopathogenic fungi. Phyllosticta citricarpa is a plant pathogenic fungus that causes 

the Citrus Black Spot (CBS) disease. This fungus was successfully agrotransformated by our group, giving its 

resistance to ammonium glifosinate and green fluorescence emission, due to bar and gfp genes insertion, 

respectively. The T-DNA insertion by A. tumefaciens can be site directed or not, and in our experiment it was 

random insertion. Thus, these inserts can produce mutants with diverse modifications, as phytopathogens 

with alterations in factors that influence the growth up, dispersion and disease development. After the P. 

citricarpa transformation procedure, the transformers were evaluated to their in vitro growth up, the in vitro 

pycnidia production and the CBS lesion formation capacity. This test was design using a new methodology 

of the CBS symptom induction in detached fruits. Different changes were finding when we compared the 

transformers with the wild type, as low rate of growth, low or any production of picnidia and different size 

rates of CBS. These alterations have being studying by Chromosome Walking approach, looking for silenced 

genes involved with pathogenic process of P. citricarpa. 


S15O06 

Epidemiology of Alternaria Brown Spot of mandarins under semi-arid conditions in Spain 

Bassimba D.D.M., Mira J.L., and Vicent A. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain. dissolu15@hotmail.com 

Alternaria Brown Spot (ABS) of mandarins, caused by Alternaria alternata, is a serious disease both in humid 

and semi-arid citrus-growing regions. The pathogen affects leaves and fruit of susceptible cultivars such as 

‘Fortune’, ‘Nova’, ‘Minneola’, and ‘Murcott’. The epidemiology of ABS was studied mainly in humid areas 

in Florida but, due to climatic differences, this information cannot be extrapolated to semi-arid regions 

like Spain. Fields studies were conducted in 2011 and 2012 in the experimental orchards at IVIA, Valencia. 

Airborne dynamics of Alternaria conidia were monitored weekly by a spore trap, and the percentage of 

pathogenic isolates was determined periodically using the selective medium ARSA and pathogenicity tests. 

The presence of inoculum on affected leaves, shoots, leaf litter, and weeds was also determined. Infection 

periods were monitored weekly by exposing trap plants of ‘Fortune’ and ‘Nova’, and environmental variables 

were recorded by an automated meteorological station. Alternaria conidia were detected through the period 

of study, but only 5% of the isolates were pathogenic. Although affected leaves and shoots were the main 

source of inoculum, the survival of the fungus in the leaf litter was higher than previously reported in Florida. 

Pathogenic isolates were detected also in weeds, but only at very low levels. Infections in trap plants occurred 

mainly May-June and September-October. A significant positive correlation was detected between disease 

incidence and rains. Funding: INIA RTA2010-00105-00-00-FEDER. 

S15O07 

Spray deposition benchmarks for control of Alternaria Brown Spot and evaluation of adjuvants 

to improve fungicide spray deposition in citrus orchards 

van Zyl J.G. 1 , Schutte G.C. 2 , and Fourie P.H. 1 

1 Citrus Research International, Department of Plant Pathology, Stellenbosch University (CRI/USPP), South Africa; and 2 Citrus Research 

International (CRI), South Africa. gideonvzyl@sun.ac.za 

Lack of citrus fruit and foliar disease control is regularly attributed to poor fungicide spray deposition. A deposition 

assessment protocol using fluorometry, photomacrography and digital image analysis was developed to study 

improvement of spray application which proved to be very accurate in determining deposition parameters on 

spray targets. To determine deposition benchmarks, young ‘Nova’ mandarin leaves were sprayed with copper 

oxychloride and SARDI Yellow Fluorescent Pigment at different concentrations and spray deposition assessed. 

Leaves were spray inoculated with Alternaria alternata [Alternaria Brown Spot (ABS) of mandarins] and symptoms 

rated. A strong linear relation was found between treatment concentration, leaf area covered by fluorescent 

pigment particles (%FPC) and Cu residue analysis. ABS control was modelled on %FPC and benchmarks for 

50% and 75% control were calculated. Selected adjuvants were evaluated in laboratory spray- and biological 

efficacy trials. Treatments varied significantly in deposition quantity and ABS control, but these parameters 

were poorly correlated, also with control levels predicted from the %FPC benchmark model. Deposition quantity 

and Cu-residues could only partially explain the level of control achieved following the addition of adjuvants. 

These anomalous results could be attributed to the effects of adjuvants on deposition quality, on pathogen 

development and synergistic effects between adjuvant and fungicide. 

S15O08 

Chemical control of Colletotrichum acutatum and C. gloeosporioides, causal agents of Citrus 

Postbloom Fruit Drop in Brazil 

Goes A. 1 , and Rinaldo D. 2 

1 Universidade Estadual Paulista (UNESP), Phytopathology, Brazil; and 2 Universidade Estadual Paulista (UNESP), Phytopathology, Brazil. 

adggoes@yahoo.com.br 

Postbloom Fruit Drop (PFD) in Brazil is caused by Colletotrichum acutatum and C. gloeosporioides. PFD is 

one of the most important fungal diseases of sweet orange in tropical and subtropical regions of the world. 


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It produces orange-brown lesions on petals, inducing the abscission of young fruitlets and the retention of 

the calyces. This study was undertaken to determine the effect of the following treatments (g or mL/hL): 

T1- nontreated control, T2- quaternary ammonia (QA) 0.5; T3- QA 0.25; T4- famoxadone/mancozeb (FA MA) 

(0.3125 31.25); T5- (FA MA) QA (0.3125 31.25) 0.5; T6- carbendazim (CA) 2.5; T7- CA QA 2.5 0.25; T8- CA 

QA 2.5 0.5; T9- fenilpiridinilamina (FE) 0.0125; T10- FE QA 0.0125 0.5, T11- trifloxystrobin/tebuconazole (TR 

TE) (0.2 0.4); T12- (0.2 0.4) 0.5; T13- conventional farm (CF) difenoconazole 0.3125 at first application plus 

three additional applications of CA at 2.5; T14- CF QA 0.5. All treatments consisted of four applications of 

fungicides at the appropriated flowering stages which were begun at pinhead stage. Intervals of applications 

were 7-13 days. The assessments were made by measuring the amount of flowers with symptoms, effective 

average number of fruits and number of fruit at harvest. The treatments T-11 and T-12 proved to be the 

most effective, reducing the abscission of young fruitlets and increasing the retention of the bottom and, 

consequently improving fruit set (P≤0.05). QA was effective only it was applied plus TR TE. 

S15O09 

Pathogenicity and genetic relationship of strains of Elsinoë australis causing Citrus Scab disease 

Hyun J.W. 1 , Yi P.H. 1 , Yun S.H. 1 , Hwang R.Y. 1 , and Levy L. 2 

1Citrus Research Station, National Institute of Horticultural & Herbal Science, RDA, Jeju, 697-943 (NIHHS, RDA), S. Korea; and 2National Plant Germplasm and Biotechnology Laboratory, USDA-APHIS-PPQ-CPHST, Beltsville, MD20705, USA. hyunjaewook@korea.kr 

Two Scab diseases are recognized currently on citrus: Citrus Scab, caused by Elsinoë fawcettii, and Sweet 

Orange Scab, caused by E. australis. Six pathotypes of E. fawcettii and two of E. australis have been described 

to date based on host range. The pathogenicity and genetic relationships among 15 isolates of E. australis 

from Korea, USA, Argentina and Brazil were investigated in this study. Based on pathogenicity tests on seven 

differential hosts, all isolates did not induce any symptoms on leaves of the seven differential hosts. In assay 

on fruit, the isolate Na-1 and KNa-2 induced the symptoms on natsudaidai but not on satsuma mandarin 

fruits at all. The isolate Ea-2 induced symptoms on sweet orange fruit. By sequence analysis of Eaut-1, 2, 3, 

4, EaNat-1 and 2 gene, the isolates were divided into three subgroups, natsudaidai pathotype group, south 

American isolates group and USA isolates group, and the natsudaidai pathotype isolates and isolates from 

USA were more closely related. We think that there is possibility that E. australis isolates were differentiated 

to some pathotypes or genotypes in this study. 

S15O10 

Association and interaction of edaphic factors with root disease related citrus decline 

Pretorius M.C. 1 , Labuschagne N. 2 , Kotze C. 1 , and McLeod A. 3 

1Citrus Research International (CRI), Nelspruit, South Africa; 2University of Pretoria (UP), Pretoria, South Africa; and 3University of 

Stellenbosch (US), Stellenbosch, South Africa. mc@cri.co.za 

Symptoms associated with root disease related citrus decline include sparse foliage, twig die-back and reduced 

growth, yield and fruit size as well as root rot. The causal factors involved in root disease related decline have 

not yet been fully elucidated. Invariably tree decline is noticed too late for the implementation of preventative 

management strategies. The aims of the study are to elucidate edaphic factors associated with citrus decline, 

so that early-diagnostic tools can be developed. Two declining orchards were selected for the study. Based 

on visual decline ratings of tree canopies, trees from three to four decline categories were selected. For 

each tree category several parameters were measured including yield, soil and leaf characteristics, soilborne 

pathogens and root disease associated symptoms. Multivariate analyses indicated that the two orchards were 

distinct. Subsequent analyses were therefore conducted separately for the two orchards. Distinct groups 

were identified for each tree category, indicating that most trees were visually correctly selected. Principal 

component analyses of the four groups of data revealed that the strongest structure existed for yield data, 

followed by soil factors, disease associated factors, and leaf parameters describing 81%, 61%, 49% and 39% 

of the variability respectively. Continued multivariate analyses will allow identification of the progressive 

changes in soil environmental interactions that lead to tree decline. 


S15O11 

Searching for citrus rootstocks resistant to Mal Secco disease: a review 

Nigro F., Ippolito A., and Salerno M.G. 

Department of Soil, Plant and Food Science, University of Bari Aldo Moro, Italy. antonio.ippolito@uniba.it 

Mal Secco Disease (MSD) is a severe tracheomycotic disease of citrus caused by the mitosporic fungus Phoma 

tracheiphila. Besides lemon, the most damaged species, MSD also affects other citrus species, such as cedar, 

lime, bergamot, chinotto, sour orange, rough lemon, Volkamer lemon, etc. When the infection is through a 

rootlet of a susceptible species, more frequently in the nursery but also in bearing plants in the grove, the 

pathogen may remain segregated for many years in the inner layers of wood, leading to the particular form 

of the disease known as ‘Mal Nero’; this syndrome is characterized by blackish discoloration of the hard 

wood and by the absence of almost any external symptom. Eventually, after several years, the pathogen 

reaches the sapwood, causing a sudden collapse of the canopy, also on resistant scions. Host resistance 

remains the most desirable goal among the measures to control MSD, and the search for new and resistant 

rootstocks, to replace the susceptible ones, has long been pursued by researches in Italy. This paper reviews 

the conclusive data collected over almost three decades of researches, conducted both in the field and in 

controlled environment, on the behaviour of putative lemon rootstocks towards MSD. The tested rootstocks 

include: alemow, sour orange (S. Marina and undetermined selections), ‘Ichang’ lemon, ‘Yuzu’ orange, 

‘Nansho Daidai’ sour orange, ‘Siamelo’, Citrange ‘Yuma’, citrumelos (‘Sacaton’, ‘Swingle 4475’, and ‘Swingle 

FF9’), and the hybrids ‘Cleopatra’ x Poncirus, and Poncirus ‘Christian’ x ‘Cleopatra’. 

S15P01 

Endophytic actinomycetes for the biological control of Phyllosticta citricarpa 

Glienke C. 1 , Savi D.C. 1 , Goulin E.H. 1 , Kava-Cordeiro V. 1 , and Silva Jr G.J. 2 

1 Federal University of Parana (UFPR), Genetics, Brazil; and 2 Fundecitrus Fundo Paulista de Apoio a Citricultura (FUNDECITRUS), 

Cientifico, Brazil. ch.glienke@gmail.com 

The Citrus Black Spot (CBS) disease has caused innumerous losses in citrus producing regions in the world, 

including Brazil, Australia and South Africa. This disease is caused by the fungus Phyllosticta citricarpa. 

Actinomycetes are widely known due to its enormous capacity to produce secondary metabolites, the 

pharmaceutical market by providing the most varied treatment options. Looking for biological control of P. 

citricarpa, the present work aimed the isolation of endophytic actinomycetes of the medicinal plant Vochysia 

divergens, and the bioprospecting of its secondary metabolites. The endophytes were tested against the fungus 

P. citricarpa in vitro and in vivo using detached orange fruits. The endophytic isolate LGMB259 presented better 

inhibitory activity in vitro and it was confronted with the fungus P. citricarpa in fruit tests. The metabolites of 

other five isolates inhibited totally the emergence of the CBS disease symptoms in tests in vivo. To determine the 

identity of these actinomycetes, the isolates were subjected to DNA sequence analysis of the rDNA 16S gene. 

Ten isolates were classified as Microbispora sp. and two isolates were classified as Streptomyces sampsonii. The 

other two isolates were identified as Micromonospora sp. and are apparently undescribed species. This is the 

first report of the actinomycetes isolation from this medicinal plant, and the first report of actinomycetes with 

activity against P. citricarpa. Financial Support: CNPq/MAPA, Fundecitrus, Fundação Araucária. 

S15P02 

Population genetics of Guignardia citricarpa in South Africa 

Carstens E. 1 , Linde C.C. 2 , Slabber R. 3 , Langenhoven S. 4 , Schutte G.C. 5 , Fourie P.H. 1 , and McLeod A. 4 

1 Stellenbosch University and Citrus Research International, Plant Pathology, South Africa; 2 Australian National University, Canberra 

ACT, Research School of Biology, Ecology, Evolution and Genetics, Australia; 3 Stellenbosch University, Central Analytical Facilities, 

South Africa; 4 Stellenbosch University, Plant Pathology, South Africa; and 5 Citrus Research International, South Africa. ec@cri.co.za 

Citrus Black Spot (CBS), caused by Guignardia citricarpa, is an economically important pathogen of citrus in 

South Africa (SA). The pathogen produces two types of spores, waterborne conidia on fruit, twigs and leaves on 

the tree, and windborne ascospores from asci in leaf litter. In SA and Australia, epidemiological studies showed 


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that only ascospores are responsible for epidemics but in Brazil conidia can also contribute to epidemics. No 

population genetic approach has been used to study the contribution of ascospores and conidia to epidemics. 

This study aims to investigate population differentiation of G. citricarpa populations in production regions, the 

relative contribution of sexual and asexual inoculum to epidemics, survival of genotypes between seasons and 

spatial distribution of genotypes. Since no molecular markers are available for this study, microsatellite markers 

were developed using next generation sequencing techniques of a SA isolate. A total of 15 polymorphic markers 

were developed which will be used to genotype populations from four production regions for investigating 

population differentiation and founder effects. The contribution of sexual and asexual spores and spatial 

distribution will be studied by genotyping populations from three different orchards during three sampling 

periods in two consecutive seasons. Altogether this information will indicate whether CBS in SA is a monocyclic 

disease that can be controlled through destruction of leaf litter containing sexual spores. 

S15P03 

First report of false melanose symptoms of Citrus Black Spot on sweet orange leaves in Brazil 

Silva-Junior G.J., Pereira R.G., Marin D.R., Wulff N.A., Scapin M.S., and Sala I. 

Fundo de Defesa da Citricultura (Fundecitrus), Scientific Department, Brazil. geraldo@fundecitrus.com.br 

Citrus Black Spot (CBS), caused by Guignardia citricarpa, is one of the most serious diseases of citrus around 

the world. In São Paulo State (SPS), Brazil, CBS was first reported in 1993. Six symptom types have been 

frequently associated with the CBS on fruits (hard spot, false melanose, lacy spot, freckle spot, cracked 

spot and virulent spot). On leaves, hard spot have been observed on lemon (Citrus limon) and rarely on 

sweet orange (C. sinensis). Recently, we observed false melanose like symptoms on ‘Valencia’ sweet orange 

leaves in groves with high CBS incidence in SPS. Initially, the symptoms on leaves, characterized by small and 

smooth black spot lesions lacking pycnidia, were misidentified as Greasy Spot or Melanose. For the correct 

diagnosis, lesions were cut from sweet orange symptomatic leaves, disinfested with 1% sodium hypochlorite 

and transferred to potato–dextrose–agar. After 14 to 21 days, G. citricarpa typical colonies were observed on 

the medium. Positive PCR results for G. citricarpa were obtained with both lesions and isolates. This is the first 

report of CBS false melanose symptoms on citrus sweet orange leaves. 

S15P04 

Biocontrol of Citrus Black Spot disease: perspectives using fungal endophytes of citrus 

Jung L.F., Goulin E.H., Savi D.C., Schuh R., Galli-Terasawa L.V., Glienke C., and Kava-Cordeiro V. 

Universidade Federal do Paraná (UFPR), Genética, Brasil. vanessagenetica@gmail.com 

Among the diseases affecting citrus production, there is Citrus Black Spot (CBS). This disease is caused by the 

fungus Phyllosticta citricarpa and its control is based on the use of fungicides. Although there is no damage in 

the internal contents, the pathogen induces lesions on the fruit skin, which lead to refusal to trade in natura, 

and in severe cases promotes premature fruit drop, reducing yield. Phytosanitary restrictions imposed by 

importing countries lead to the rejection of entire loads of fruit with symptoms, causing great losses to some 

producing countries. Due to environmental and health concerns, alternatives for the control of this disease 

must be found. The use of microorganisms for the biological control and biopanning of natural products 

appears as a promising alternative. Endophytic microorganisms have been highlighted by the growing number 

of new bioactive compounds. Considering these aspects, hundreds of citrus endophytic fungi were isolated 

from leaves of sweet orange, in different culture conditions. A total of 67 morphotypes were grouped and 

investigated for their potential antagonistic effect to the fungus P. citricarpa. Among them, six showed to be 

promising in paired culture test. In tests of volatile metabolites, one isolate showed the best results. This 

fungus was able to cause inhibition in colony diameter of P. citricarpa by 60%, and the volatiles of this fungus 

inhibited by 100% the formation of pycnidia of the pathogen in citrus leaves assays. In tests with detached 

sweet orange fruit inoculated with P. citricarpa, there was 26% decrease of mean diameter lesions of CBS. 

This result is of great importance, since the exposure of postharvest fruits to volatile compounds is a process 

that can be performed, particularly in fruit intended for export. This is the first report of an endophytic fungal 

volatile compound with antagonist effect against P. citricarpa. 


S15P05 

Modelling of Guignardia pseudothecium maturation and ascospore dispersal in citrus orchards 

Fourie P.H. 1 , Schutte G.C. 1 , Serfontein S. 2 , and Swart S.H. 2 

1 Citrus Research International (CRI), Disease Management, South Africa; and 2 QMS-Agriscience (Letsitele), South Africa. 

phf@cri.co.za 

Ascospores are considered the most important inoculum source of Citrus Black Spot (CBS), caused by 

Guignardia citricarpa, but pseudothecium maturation and ascospore dispersal are inadequately studied. 

Guignardia ascospore trapping and concomitant weather data were obtained for three localities for three 

seasons (July through March from 2006 to 2009) in the Limpopo province of South Africa. Degree-days 

accumulated until first seasonal ascospore discharge (>10°C with 1 July as biofix; DDtemp), and DDtemp 

accumulated on rainy (rainfall > 0.1 mm; DDrain) and moist days (vapour pressure deficit < 5 hPa; DDvpd) 

were used in two Gompertz models to predict onset of ascospore dispersal: a temperature model [Event = 

exp(-exp(-(-2.725 0.004 × DDtemp)))] and a temperature/moisture model [Event = exp(-exp(-(-3.238 0.008 

× DDvpd 0.004 × DDtemp -0.009 × DDrain)))] (R2 = 0.608 and 0.658, respectively). Both models predicted 

a delay in pseudothecium maturation in climates with colder winters and springs, while the temperature/ 

moisture model predicted a further delay in drier seasons or climates. A Gompertz equation was also used to 

predict the proportion of Guignardia ascospores trapped (PAT) per season from DDtemp data accumulated on 

wet or moist days from the first seasonal ascospore discharge [PAT = exp(-4.096 × exp(-0.005 × DDwet2); R2 

= 0.908]. These models can be used to predict the onset and dynamics of ascospore dispersal in climatically 

diverse regions. 

S15P06 

Infectious period of Citrus Black Spot on sweet orange 

Lourenço S.A. 1 , Gasparoto M.C.G. 1 , Spósito M.B. 1 , Amorim L. 1 , and Gottwald T.R. 2 

1 Escola Superior de Agricultura Luiz de Queiroz (ESALQ), Fitopatologia e Nematologia, Brazil; and 2 Agricultural Research Service (ARS), 

United States Department of Agriculture, USA. salouren@hotmail.com 

Citrus Black Spot (CBS) is an important fungal disease, caused by Guignardia citricarpa. The risk of introduction 

and spread of CBS to new unaffected citrus-producing areas is a major concern for those orchards attempting 

to remain free of the disease. It has never been demonstrated that G. citricarpa-infected fruit have established 

infections in commercial diseased-free areas. The period of production of spores in fruit lesions is an important 

variable in a model for risk assessment. The objective of this study was to evaluate the infectious period of 

CBS on sweet oranges. Twenty infected oranges treated with carnauba wax with hard spot symptoms of CBS 

were kept in a humid chamber until freckle spot symptoms developed. When the first pycnidium formed, 

50 µl drop of sterile water was placed on one freckle spot lesion per fruit. After four hours, the water drop 

was transferred to 250 µl of sterile water with Tween-20 (1%). Every 48 hours over 40 days, the number 

of pycnidia and the number of conidia formed in each lesion were counted. The experiment was repeated 

twice. The first pycnidia were observed 2-7 days after the appearance of typical freckle spots. The number 

of pycnidia increased until 30-40 days, and ranged from 1 to 31 per lesion. Conidia liberation started at 2-12 

days and stopped 16-38 days after pycnidia formation. The number of conidia ranged from 0 to 109,875 per 

lesion. The average infectious period was 15 days and ranged from 0 to 26 days. 

S15P07 

Characterization of Guignardia spp. from citrus fruit in Argentina 

Kornowski M.V., and Agostini J.P. 

Instituto Nacional Tecnologia Agropecuaria (INTA), Plant Pathology E.E.A. Montecarlo, Argentina. jpagostini@montecarlo.inta.gov.ar 

Citrus Black Spot (CBS) is a fruit disease caused by Guignardia citricarpa while G. mangiferae is a nonpathogenic 

species that also infects citrus fruit. Four kinds of fruit symptoms are associated with this disease, 

viz. hard spot, freckle spot, false melanose, and virulent spot. Both species can be characterized by either 

molecular means or growth on culture media. For molecular characterization with PCR, 25 isolates from 


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the northwestern and 64 from the northeastern citrus regions of Argentina were analyzed with the primers 

NP-Br-ITS-Gc and NP-Br-ITS-Gm specific for each Guignardia spp. From these orchards, G. mangiferae was 

recovered from 12.5% of the samples as well as from all kinds of symptoms (except virulent spot) as well 

as 12.5% from hard spot, 37.5% from freckle spot, and 25% from false melanose as well as 25% from a new 

lesion type, the so-called ‘moteado’ isolated from lemon fruit. CBS morphology was characterized on oat 

meal agar for over 257 isolates made from citrus groves of the northeastern parts of Argentina with five kinds 

of symptoms classified as hard spot (45.5%), freckle spot (35.0%), false melanose (3.5%), virulent spot (7.4%), 

and ‘moteado’ (8.6%). Of the isolates collected, 83.6% were G. citricarpa that developed characteristic yellow 

halos on oat meal agar, whereas the rest were of the non-pathogenic species made from hard spot lesions. 

Both fungal species can therefore be recovered from the same kind of fruit symptoms. 

S15P08 

Integrated approaches to minimize Alternaria Brown Spot of citrus in Italy 

Bella P. 1 , Russo M. 2 , Tomasello M. 2 , Catara A. 2 , Catara V. 1 , and La Rosa R. 1 

1 Dipartimento di Scienze delle Produzioni Agrarie e Alimentari (DISPA), Italy; and 2 Parco Scientifico e Tecnologico della Sicilia, Italy. 

larosar@unict.it 

Alternaria Brown Spot of citrus by the fungus Alternaria alternata causes considerable damage on hybrids of 

‘Dancy’ mandarin, such as brown to black spots on leaves, fruit and young twigs, resulting in low fruit yield 

and poor quality. After the first detection in Italy in 2000, the disease has been reported on different mandarin 

hybrids as ‘Nova’ and ‘Winola’ and under specific conditions on sweet orange as ‘Valencia’. Epidemiological 

observations carried out since 2003 in a grove of ‘Fortune’ mandarin grafted onto Citrange ‘Troyer’ showed 

that the disease development is related to rainfall, temperature, and inoculum density. Flower and leaf 

infections, occurring before fruit set and development, directly affected fruit yield and quality. Infections 

on leaves and twigs in September/October increased the fungal inoculum, leading to severe infections the 

following year. Cultural practices such as tree spacing, pruning and intercropping associated to spray programs 

helped in reducing disease severity on twigs and fruits and concentration of airborne conidia. The number 

of infected twigs and leaves was reduced up to 30% in wide tree spacing ‘Fortune’ plots and by 80% in young 

trees plots. Negative effects on disease pressure was observed on a ‘Fortune’ plot subjected to early pruning, 

where infected leaves and twigs increased up to 40% after heavy spring rains. Instead, lower values of disease 

index were recorded on shoots, leaves and fruits of ‘Fortune’ plants intercropped with other citrus species 

or hybrids. 

S15P09 

Varietal resistance and management of Alternaria Brown Spot in Brazil 

Azevedo F.A., Pacheco C.A., Martelli I.B., and Polydoro D.A. 

Centro de Citricultura Sylvio Moreira/Instituto Agronômico, Brazil. fernando@centrodecitricultura.br 

Alternaria Brown Spot (ABS), caused by Alternaria alternata, is the major fungal disease of mandarins in the 

world. Therefore this study evaluated in Brazil: (i) resistance to ABS in different genotypes; (ii) use of pruning 

in winter season as way of control to ABS; and (iii) correlation between Citrus Leaf Miner (CLM) and ABS. The 

severity of the disease (ABS) in fruit of 31 genotypes was evaluated in the field. In parallel, in vivo and in vitro 

inoculations with A. alternata were performed on leaves. The effects of pruning were evaluated in a ‘Murcott’ 

tangor orchard, evaluating percentage of fruit damaged area and disease incidence. Finally, resistant and 

susceptible varieties of mandarin were evaluated in controlled experiments with CLM and ABS presence. Most 

of the genotypes were symptomatic in the field and after inoculation with A. alternata. The disease was most 

severe on ‘Nova’, ‘África do Sul’, ‘Ponkan’ and ‘Murcott’. Cultivars like ‘Cravo’, ‘Nules’ and ‘Ortanique’ were 

tolerant, and ‘Fremont’ was highly resistant to the fungus. Winter pruning reduced the damage caused by ABS. 

Regarding the correlation between ABS and CLM, the results showed that susceptible varieties had greater 

damage when the insect was present, while resistant varieties did not lose their resistance characteristic after 

the CLM attack. Thus, we conclude from this study that there are varieties tolerant and resistant to ABS, and 

both winter pruning and CLM control are important in ABS management. 


S15P10 

Outbreak and occurrence of Alternaria Brown Spot in China 

Huang F., and Li H.Y. 

Institute of Biotechnology, Zhejiang University, China. rm12407@hotmail.com 

Symptoms of Alternaria Brown Spot (ABS) caused by Alternaria alternata were first reported in Australia 

in 1903. The disease is currently widespread in America, Africa, and the Mediterranean Basin. ABS is a 

devastating disease, especially on juvenile tissues of tangerines and tangerine hybrids, and also slightly on 

grapefruits. Nearly one century after its first description in Australia, ABS is now reported in China. In 2007, 

the disease was observed in Chongqing, and it was further detected in Guangxi, Hunan, Zhejiang, Yunnan 

and Guangdong. Currently, ABS affects nearly half of citrus-growing regions in China and it is still spreading. 

We suggest that ABS might be a long existing disease in China, but it has been ignored because the pathogen 

affects mainly juvenile tissues, and its isolation is often masked by Colletotrichum species, so ABS might be 

easily confused with anthracnose associated to C. gloeosporiodes. Further studies are necessary to determine 

the prevalence of ABS in all of Chinese citrus-growing regions, and to establish appropriate disease control 

strategies combining fungicide sprays and cultural practices. 

S15P11 

Evolution of symptoms caused by Alternaria alternata on ‘Nova’ mandarin fruit and its 

schematic sequence 

Burdyn L. 1 , Garran S.M. 1 , and Avanza M.M. 2 

1 Instituto Nacional de Tecnología Agrícola (INTA), Concordia, Entre Ríos, Argentina; and 2 Catedra de Estadística, Facultad de Ciencias 

Agrarias, Universidad Nacional del Nordeste (FCA-UNNE), Corrientes, Argentina. lburdyn@correo.inta.gov.ar 

In the Northeast of Entre Ríos, Argentina, detection of Alternaria Brown Spot (ABS) caused by Alternaria alternata 

is recent. It causes economic damage on ‘Murcott’ tangerine and ‘Nova’ mandarin plantations, both of high 

commercial value for export as well as for the domestic market. ABS causes necrosis and defoliation of shoots. 

Besides, it causes a variety of symptoms on fruits, affecting their quality and, while in early infections, causing 

premature fruit drop. In addition, ABS symptoms may also lead to confusion and misdiagnosis of quarantine 

diseases such as Citrus Canker, Citrus Black Spot and even Scab since some symptom stages of all these diseases 

are similar in appearance to ABS. In order to clarify the paths followed by ABS symptoms along fruit growth and 

ripening, they were monitored since their initial stages till complete maturity. An experiment was performed in a 

‘Nova’ mandarin commercial plot with high incidence and severity of ABS and where a chemical control trial was 

being performed. Fifty fruitlets per experimental unit were labelled, identified, and tracked on monthly bases, 

counting the type and number of symptoms appearing on each of them. All types of ABS symptoms were classified 

using a qualitative scale of nine stages previously developed. This monitoring included statistical analysis of the 

frequency distributions of the different stages and the verification of the proposed sequences. Results helped to 

clarify ABS symptoms and to facilitate their differentiation from quarantine diseases with similar symptoms. 

S15P12 

Commercial-scale Alternaria Brown Spot resistance screening as the first step in breeding new 

mandarins for Australia 

Miles A.K. 1 , Newman T.K. 2 , Gultzow D.L. 2 , Parfitt S.C. 2 , Drenth A. 1 , and Smith M.W. 2 

1 Ecosciences Precinct, Queensland Department of Agriculture, Fisheries and Forestry, Australia; and 2 Bundaberg Research Station, 

Queensland Department of Agriculture, Fisheries and Forestry, Australia. malcolmsmith1966@hotmail.com 

Rapid-screening-tests and an appreciation of the simple genetic control of Alternaria Brown Spot susceptibility 

have existed for many years, and yet the application of this knowledge to commercial-scale breeding programs 

has been limited. Detached leaf assays were first demonstrated more than 40 years ago and reliable data 

suggesting a single gene determining susceptibility has been emerging for at least 20 years. However it is only 

recently that the requirement for genetic resistance in new hybrids has become a priority, following increased 

disease prevalence in Australian mandarin production areas previously considered too dry for the pathogen. 


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Almost all of the high-fruit-quality parents developed so far by our breeding program are susceptible to this 

disease necessitating the screening of their progeny. This is done by simply spraying 3-6 month old hybrid 

seedlings with a spore suspension derived from a toxin-producing field isolate, then incubating these seedlings 

in a cool room at 25°C and high humidity for five days. Susceptible seedlings show clear disease symptoms and 

are culled. After using this approach for only two seasons we now have more than 11,000 hybrids growing in 

field progeny blocks that are known to be genetically resistant to brown spot disease. 

S15P13 

Difference in susceptibility to Alternaria Brown Spot between young and mature ‘Minneola’ 

tangelo leaves 

Liarzi O., Sela N., and Ezra D. 

A.R.O., The Volcani Center, Bet Dagan, Department of Plant Pathology and weed research, Israel. dezra@volcani.agri.gov.il 

Alternaria alternata, the cause of Alternaria Brown Spot, is an important disease of mandarins in Israel. This 

fungus causes symptoms on fruit, shoots and young leaves of susceptible cultivars. A specific toxin (ACT), 

produced by the fungus is well characterized but its specific target site in the host is still unknown. The fact 

that symptoms are visible only on young leaves, suggest that there may be a factor(s) differentially expressed 

in the young leaves, and absent from mature ones. Using the Suppression Subtractive Hybridization (SSH) 

method we compared and isolated cDNA molecules expressed only in young (96 sequences) or mature (110 

sequences) leaves. All sequences were analyzed using Blast2GO software. Gene ontology of the sequences 

revealed differences between young and mature leaves. In order to find if these differences play a role in 

gaining susceptibility or resistance to A. alternata of young and mature leaves, respectively, qPCR analysis of 

selected genes in the presence and absence of the pathogen is in progress. 

S15P14 

Screening for Alternaria Brown Spot resistance in the triploid mandarin breeding programme in Spain 

Bassimba D.D.M., Vicent A., Cuenca J., Aleza P., and Navarro L. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain. dissolu15@hotmail.com 

About 1,200-2,000 seedless hybrids are obtained each year in the triploid mandarin breeding program in Spain. 

Some of the parents used, such as ‘Fortune’, ‘Murcott’ and ‘Minneola’, are susceptible to Alternaria Brown Spot 

(ABS) caused by Alternaria alternata. The susceptibility to ABS is partially transmitted to the progeny, so evaluation 

of genotype susceptibility was a critical target since the beginning of the breeding program. Traditionally, longterm 

field trials under endemic disease conditions were used to evaluate disease susceptibility. However, these 

experiments are costly, time-consuming, and difficult to apply with large numbers of genotypes. Therefore, two 

alternative methodologies were evaluated. Detached young leaves in humid chambers and potted plants with 

young shoots were inoculated by spraying a spore suspension. Different combinations of genotype, leaf age, spore 

concentration, temperature, and leaf wetness duration were evaluated and used as explanatory variables. The 

duration of the incubation period (i.e. from inoculation to symptom expression) and disease severity were used 

as response variables. The inoculation of detached leaves discriminated only between susceptible and resistant 

cultivars. The interaction between leaf age and incubation period duration in inoculated potted plants was 

correlated with the degree of susceptibility observed in the field. The implementation of these two methodologies 

facilitated the commercial release of new seedless triploid hybrids, such as ‘Garbí’ and ‘Safor’, resistant to ABS 

despite that ‘Fortune’ is one of the parents. Funding: INIA RTA2010-00105-00-00-FEDER. 

S15P15 

Enhancing of physiological parameters improves resistance against Alternaria Brown Spot of mandarins 

Llorens E., Fernández-Crespo E., Camañes G., Lapeña L., and García-Agustín P. 

Universitat Jaume I (UJI), Departamento de Ciencias Agrarias y del Medio Natural. ESTC, Spain. ellorens@uji.es 

The appearance of Alternaria Brown Spot (ABS) in Spanish citrus regions forced the abandonment of the 

‘Fortune’ mandarin production due to the difficulty of controlling this disease with fungicides. Environmental 


concerns have prompted governments to promote alternatives to the application of synthetic chemicals to 

reduce risks and impacts of pesticide use. The development of novel resistance-inducing chemicals represents 

an alternative to protect crops against pathogens. Over the last years we have been working on strategies 

based on natural compounds and we have demonstrated that soil-drench treatment with hexanoic acid protect 

citrus against Alternaria alternata. In the present work, we have analyzed the effectiveness of hexanoic acid 

(Hx) in the control of ABS disease in ‘Fortune’ plants, and the physiological and metabolic changes associated 

with the Hx treatment. Preliminary results show an improvement of all the physiological parameters analyzed, 

including transpiration, photosynthesis or chlorophyll levels. Moreover, the metabolomics study of A. alternata 

infection and hexanoic acid treatment show strong changes in the metabolic profile depending on infection 

and treatment. In conclusion, these studies will shed light into the complexity underlying induced disease 

resistance. Hx-IR represents an attractive tool for the molecular characterization of the priming phenomenon 

and for the integrated pest management strategies with the advantage of being a natural compound. 

S15P16 

Strobilurin resistance of Alternaria alternata, the causal agent of Alternaria Brown Spot, in 

Florida tangerine hybrid groves 

Vega B., and Dewdney M.M. 

Citrus Research and Education Center, University of Florida (CREC, UF), Plant Pathology, USA. mmdewdney@ufl.edu 

In Florida, strobilurin fungicides are commonly used for Alternaria alternata control but are becoming less 

effective. A statewide survey was initiated in 2010 to determine the sensitivity of A. alternata populations to 

azoxystrobin and pyraclostrobin covering 8 counties and 46 blocks. Azoxystrobin and pyraclostrobin sensitivity 

was determined via a resazurin-based microtiter assay. Resistance was widespread among counties and 69% 

of isolates were highly resistant with EC50 (effective concentration to inhibit 50% growth) values greater than 

5 µg/ml for azoxystrobin and 1 µg/ml for pyraclostrobin, while the mean EC50 values for sensitive isolates 

were 0.1680 and 0.0216 µg/ml respectively. Cross-resistance was demonstrated by highly significant and 

strong correlations (P < 0.0001). Mixed populations of sensitive and resistant isolates were in 37% blocks and 

only resistant isolates in 50%. Disease severity was high in the cultivars ‘Minneola’ and ‘Dancy’ and low in 

‘Sunburst’ and ‘Orlando’. Our observations showed that strobilurin resistance occurred more frequently on 

susceptible cultivars with intense fungicide use (P < 0.0001). Partial sequencing of the cytochrome b gene was 

used to evaluate the resistant genotypes and the typical resistance inducing amino acid substitution of G143A 

was found. Two introns profiles were found in cytochrome b but did not change the isolate phenotype. Profile 

II was more frequently associated with resistant isolates and sensitive isolates were often profile I. 

S15P17 

Evaluation of fungicide mixtures as replacement for carbendazim for Citrus Postbloom Fruit Drop control 

in Brazil 

Silva-Junior G.J. 1 , Spósito M.B. 2 , Marin D.R. 1 , and Amorim L. 3 

1 Fundo de Defesa da Citricultura (Fundecitrus), Scientific Department, Brazil; 2 Escola Superior de Agricultura Luiz de Queiroz (Esalq), 

Department of Crop Science, Brazil; and 3 Escola Superior de Agricultura Luiz de Queiroz (Esalq), Department of Plant Pathology and 

Nematology, Brazil. geraldo@fundecitrus.com.br 

Control of Citrus Postbloom Fruit Drop (PFD), caused by Colletotrichum spp., is based mainly on fungicide 

sprays. Carbendazim was an important fungicide used for PFD control in Brazil, but recently, it was banned 

in export citrus production. Thus, the search for other fungicides to control of PFD became necessary. In 

this study, the effectiveness of carbendazim was compared to the mixtures trifloxystrobin/tebuconazole (Tri/ 

Teb) and cyprodinil/fludioxonil (Cyp/Flu). Two experiments were carried out in 2009⁄2010 season in 18 and 

20–yr–old ‘Pera’ sweet orange groves in Sao Paulo State, Brazil. Four sprays of carbendazim (1000g⁄ha), Tri/ 

Teb (80 and 160g⁄ha) or Cyp/Flu (94 and 63g⁄ha) were performed at 7–day interval, starting at the green bud 

stage. Untreated control (UTC) trees received no fungicides. The incidence of symptomatic petals, number of 

persistent calyces and fruit set per branch, and yield per tree were assessed. In both experiments, only Tri/Teb 

differed significantly from the UTC trees for all variables studied. While trees sprayed with Tri/Teb yielded 88 


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and 41 kg, UTC trees produced 30 and 6 kg, in experiments 1 and 2, respectively. Fruit yield was intermediary 

in both experiments for carbendazim (61 and 23 kg) and Cyp/Flu (53 and 13 kg). Therefore, Tri/Teb mixture 

is a satisfactory, more efficient option for replacing carbendazim for control of PFD. Supported by FAPESP 

(08⁄54599–2 and 08⁄54176–4). 

S15P18 

Survival of Colletotrichum acutatum in citrus leaves 

Pereira W.V. 1 , Tanaka F.A.O. 1 , Rodrigues M.B.C. 2 , and Massola-Junior N.S. 1 

1 University of São Paulo (USP), Plant Pathology and Nematology, Brazil; and 2 University of São Paulo (USP), Genetics, Brazil. 

wvpereira@hotmail.com 

Citrus Postbloom Fruit Drop (PFD) disease caused by Colletotrichum acutatum became recently an important 

issue for citrus industry in Brazil. The determination of the source of inoculum and its survival period is 

essential to understand the epidemiology and to develop strategies for the management of this disease. The 

survival of C. acutatum on the surface of orange leaves was investigated. Leaves from ‘Pera’ sweet orange 

saplings were inoculated with 105 conidia/mL and kept in a moist chamber for 48 h. For greenhouse and 

field experiments, the saplings were inoculated with standard isolates. For growth chamber experiments 

(21°C and 27°C), it was used a GFP gene-labeled isolate. Samples of inoculated leaf areas were taken and 

evaluated monthly. This evaluation was made by the isolation of C. acutatum in a semi-selective medium and/ 

or visualization by fluorescence in a confocal microscope. Under controlled conditions, the pathogen survived 

on the surface of the leaves for seven months at 21°C and for four months at 27°C. In the greenhouse, the 

survival was three months and two months in the field. Recognition of the isolated cultures was made by PCR. 

These data indicate that orange leaves can play an important role as source of inoculum for PFD. 

S15P19 

Pollen exudate stimulates conidial germination of Colletotrichum acutatum 

Gasparoto M.C.G., Lourenço S.A., Marques J.P.R., Appezzato-da-Glória B., and Amorim L. 

Escola Superior de Agricultura Luiz de Queiroz (ESALQ), Fitopatologia e Nematologia, Brazil. mcggaspa@yahoo.com 

Postbloom Fruit Drop, caused by Colletotrichum acutatum and C. gloeosporioides, is an important citrus 

disease in the southwestern region of São Paulo State in Brazil. The high frequency of rain during the blooming 

period causes explosive epidemics. Citrus flower extract, resulting from the contact of rainwater with petals, 

stimulates the germination of appressoria and secondary conidia formation. The objective of this study was 

to evaluate the conidial germination of C. acutatum in the presence of pollen exudate. Anthers were removed 

from flowers of healthy citrus plants and transferred to 2 mL-sterile water. This mixture was agitated and the 

suspension was adjusted to 105 pollen/mL. Conidial suspension was adjusted to 105 spores/mL. Three 35 

µL-aliquots of conidial suspension plus three 35 µL-aliquots of pollen suspension were placed on polystyrene 

Petri dishes, totaling 70 µL of a homogeneous suspension in each aliquot. The control was obtained with 70 

µL-aliquot of spore suspension. Each dish was placed inside a gerbox containing a filter paper and 30 µL of 

sterile water. The gerboxes were incubated in growth chambers at 24°C, without light, for 2, 4, 6, 8, 10, 12, 24 

hours. Spore germination was calculated observing 100 conidia per aliquot. Twenty-four hours after in vitro 

inoculation, conidial germination was 100% in the presence of pollen exudate and 8% in its absence. 

S15P20 

Fungal diseases of citrus in Panama 

Aguilera-Cogley V. 1 , and Vicent A. 2 

1Instituto de Investigaciones Agropecuarias de Panamá (IDIAP), Laboratorio de Protección Vegetal, Panamá; and 2Instituto Valenciano 

de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain. avicent@ivia.es 

The citrus-growing area in Panama has increased considerably in recent years. Disease problems are frequently 

observed in the orchards, but in most cases their etiology is unknown, complicating the design of effective 


control strategies. A survey was initiated in 2010, visiting 50 fields in different regions in the country. In each 

orchard, symptoms were characterized and samples were collected from affected organs. Isolations from 

symptomatic tissues were made on general and selective media. Fungal isolates were transferred to PDA and 

V8 for morphological identification. In addition, molecular identification was carried out on representative 

isolates by amplifying and sequencing the ITS region. Necrotic pustules on the leaves, chlorosis, and premature 

defoliation were observed in 75% of the surveyed orchards. Mycosphaerella citri, the causal agent of Citrus 

Greasy Spot, was consistently isolated from the affected tissues. Lesions on petals and premature fruit drop 

were also observed in some sweet orange and lime orchards. Colletotrichum acutatum was consistently 

isolated from these lesions, and pathogenicity tests identified the isolates as the causal agent of Postbloom 

Fruit Drop. Finally, symptoms of Melanose on sweet orange leaves and fruit were associated with Phomopsis 

sp. In conclusion, the results indicated that Greasy Spot is the prevalent fungal disease of citrus in Panama. 

Funding: Programa de Formación de los INIA de Iberoamérica. 

S15P21 

Epidemiology and control of Citrus Greasy Spot in Panama 

Aguilera-Cogley V. 1 , and Vicent A. 2 

1Instituto de Investigaciones Agropecuarias de Panamá (IDIAP), Laboratorio de Protección Vegetal, Panamá; and 2Instituto Valenciano 

de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain. avicent@ivia.es 

Greasy Spot, caused by Mycosphaerella citri, is the main fungal disease of citrus in Panama. The disease induces 

leaf chlorosis, necrotic pustules, and premature defoliation, reducing fruit production and quality. Due to the 

lack of epidemiological information, strategies for greasy spot control in Panama are not satisfactory. In 2011, 

a study was set up in a commercial ‘Valencia’ sweet orange orchard in Cocle Province to characterize the 

main epidemiological traits of the disease. Airborne ascospore concentration was evaluated weekly using a 

spore trap. Inoculum dynamics in the leaf litter was assessed by means of a wind tunnel, and infection periods 

were determined by exposing trap plants. Environmental data were recorded with a meteorological station. 

In addition, two field trials were conducted to evaluate the efficacy of different spray schedules using the 

fungicide fenbuconazole. Most ascospores of M. citri were detected in the orchard air during March, April and 

May. Inoculum potential in the leaf litter and disease severity in trap plants was also high in spring. Rainfall 

was very high through the period of study. A significant negative correlation was detected between rainfall 

and inoculum potential, due to accelerated leaf litter decomposition under rainy conditions. Fenbuconazole 

applications significantly reduced disease incidence compared to the non-treated control. Funding: Programa 

de Formación de los INIA de Iberoamérica. 

S15P22 

Biological control of Citrus Canker and Melanose using rhizobacteria in Korea 

Ko Y.J., Kang S.Y., and Jeun Y.C. 

Jeju National University (JNU), Plant Resources & Environment, Republic of Korea. ycjeun@jejunu.ac.kr 

Many rhizobacteria are known not only as resistance inducers against various plant diseases, but also as 

biological control agents in various plant diseases due to their antagonistic effects. In this study bacterial 

strains were isolated from the rhizosphere of annual plants growing on Jeju Island in Korea. Four bacterial 

isolates viz. MRL408-3, TRH423-3, TRH415-2, and THJ609-3 were selected from over 100 bacterial isolates 

using in vitro tests against Xanthomonas citri subsp. citri and Diaporthe citri, the cause of Citrus Canker and 

Melanose, respectively. They are the most important citrus diseases in Korea. Bio-tests on citrus branches 

showed that the disease severity of both pathogens was reduced by the bacterial isolates after inoculation. 

Isolates MRL408-3 and TRH423-3 were identified as Burkholderia gladioli, TRH 415-2 as Pseudomonas 

fluorescens and THJ609-3 as P. pudia by analysis of internal transcript spaces (ITS) in rDNA sequencing. These 

bacterial isolates may be useful for the control of Citrus Canker and Melanose in Korea on organic farms 

where the use of fungicides is not permitted. 


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S15P23 

Expression profiles of differentially regulated genes of citrus during infection by Elsinoë fawcettii 

Hyun J.W. 1 , Yi P.H. 1 , and Kim Y.J. 2 

1 Citrus Research Station, National Institute of Horticultural & Herbal Science, R.D.A. Jeju, S. Korea; and 2 College of Life Sciences and 

Biotechnology, Korea University, S. Korea. hyunjaewook@korea.kr 

Citrus Scab is a devastating disease of citrus in JeJu island of Republic of Korea. Citrus Scab is caused by the 

fungus Elsinoë fawcettii and impacts fruit quality and appearance. To identify citrus genes involved in the 

response to the citrus scab in satsuma mandarin (Citrus unshiu), expression profiles were investigated using an 

citrus oligo array representing 24,100 genes. Expression profiles were captured at four different time-points 

after inoculation at 12, 24, 48, and 72 h, together with those at 0 h (uninoculated control). A total of about 

2,600 genes were found to be significantly modulated in response to at least one of the four time points. The 

categories included citrus genes associated with sugar metabolism, plant defense, phytohormone, and cell 

wall metabolism, as well as 10 other gene categories. Over the three time points after inoculation, 635 genes 

were commonly up-regulated and 374 genes were down-regulated. Both sets of genes were classified based 

on their functional categories. Those up- or down-regulated genes encode transcription factors, signaling 

components, defense-related genes, transporter, and metabolism, all of which have been associated with 

disease response in various plants, suggesting that similar response pathways are involved in Citrus Scab. 

S15P24 

Biological control of Phytophthora sp. and Fusarium sp. in citrus nurseries in Egypt 

Ahmed Y. 1 , Ippolito A. 2 , El-Shimy H. 3 , D’Onghia A.M. 4 , and Yaseen T. 4 

1 Department of Agri-Food and Environmental Systems Management (DiGeSA), Plant Pathology Section, University of Catania, Italy; 

2 Dipartimento di Protezione delle Piante e Microbiologia Applicata, (DPPMA), Università degli Studi di Bari, Italy; 3 Plant Pathology 

Research Institute (PPATHRI), Agriculture Research Center, Egypt; and 4 Centre International de Hautes Etudes Agronomiques 

Méditerranéennes (CIHEAM), Mediterranean Agronomic Institute of Bari (MAIB), Italy. yosra242@yahoo.com 

Phytophthora sp. and Fusarium sp. are the most important soil-borne pathogens of citrus in Egypt. Control 

methods based on the use of resistant rootstocks and good agricultural practices are not always satisfactory. 

Application of effective chemical treatments to citrus plants has reduced losses, but development of fungicide 

resistance is a legitimate concern. Since biological control is an interesting alternative, this study assessed the 

potential of two commercial biocontrol agents Clontori (Trichoderma harzianum and Clonostachys rosea) 

and BioArc (Bacillus megaterium) alone or in combination with an organic biofertilizer (Guianto) at 0.5 and 

1%. The efficacy of this treatment was evaluated on citrus growth and inoculum density of Phytophthora 

sp. and Fusarium sp. Trials were carried out in two Egyptian nurseries on Volkameriana lemon and sour 

orange seedlings. Results showed that Clonotri and BioArc caused an increase in plant height and root dry 

weight, and were significantly effective in reducing Phytophthora propagules and Fusarium populations in the 

rhizosphere of treated seedlings as compared to the nontreated control. The data revealed that 1% Guanito 

increased significantly citrus plant vegetative parameters (plant height and root dry weight). The beneficial 

activities of both Clontori and BioArc were further increased in the presence of 1% Guanito rather than 0.5%. 

S15P25 

Dry Root Rot, an alliance between Fusarium solani and Phytophthora or other factors against 

citrus in California 

Adesemoye A.O. 1 , and Eskalen A. 2 

1 Adekunle Ajasin University, Department of Microbiology, Akungba-Akoko, Ondo State, Nigeria; and 2 University of California, Riverside, 

Dept. of Plant Pathology and Microbiology, U.S.A. akif.eskalen@ucr.edu 

Fusarium solani is a weak pathogen of citrus that causes Dry Root Rot (DRR) only when a tree is under stress. 

Some stressors that results in in DRR are from Phytophthora spp., Citrus tristeza virus (CTV), wounding by 

gophers and rodents or girdling practices. This study was conducted to understand the seasonal occurrence, 

survival, and distribution of F. solani, and Phytophthora spp. and other factors associated with DRR in California. 

During a survey in 2009-2010, infected trees were rated for disease severity using a rating scale of 1 to 5. 

Samples were collected in eight citrus growing counties - Fresno, Kern, Riverside, San Diego, San Luis Obispo, 


Santa Barbara, Tulare, and Ventura. Small pieces of tissue from symptomatic root samples were plated onto 

potato dextrose agar amended with 0.01% tetracycline (PDA-Tet) to isolate fungi and PARPH medium to isolate 

Phytophthora spp. About 450 isolates were recovered from spring 2010 to winter 2011. Isolates were examined 

for their identification morphologically. Isolates were further identified using molecular methods using Internal 

Transcribed Spacer, Beta Tubulin, and Translation Elongation Factor. Pathogenecity tests were conducted with 

healthy citrus trees of the same variety from which initial isolations were made. The results showed that in 

addition to Fusarium solani, P. citrophthora, and P. nicotianae, two additional Fusarium species - F. oxysporum 

and F. proliferatum -are playing important roles in causing DDR disease of citrus. Currently, no correlation 

has been found between soil nutrient content and the disease. These findings are important for the current 

management of DRR and will help in designing integrated pest management study on DRR. 

S15P26 

Efficacy of water soluble silicon in managing Fusarium Dry Root Rot of citrus 

Marais L.J. 

Leffingwell Ag, Research & Development, USA. lmarais@leffingwellag.com 

Dry Root Rot (DRR) of citrus caused by the soil-borne fungus Fusarium solani is regarded as a weak pathogen 

infecting trees under stresses caused by over irrigation and root damage caused by certain fertilizers. 

Substantial losses in tree mortality and production are caused by this disorder. There are currently no 

effective fungicidal treatments known for the control of this disease. Control or management is based on 

cultural practices which include efficient irrigation and fertilizer management. Soluble or aqueous silicon 

has long been recognized for its prophylactic role in alleviating plant diseases when absorbed by plants. The 

effect of soil and foliar applications of two aqueous silicon products (SilMatrix, PQ Corp and Carbon Defense, 

Floratine Biosciences, Inc.) on managing DRR in mature ‘Valencia’ orange on ‘Troyer’ Citrange rootstock was 

investigated. Applications were made to DRR affected trees at 6-8 weekly intervals over a period of three 

years. Tree condition was rated on a scale of 0 to 4 with 0 = healthy appearing trees and 4 = dead trees. 

Mortality ratings for untreated controls, SilMatrix and Carbon Defense treatments were 66%, 22% and 11% 

respectively. SilMatrix enhanced tree condition by 50% in trees rated 1.0 prior to treatment and Carbon 

Defense enhanced tree condition by 69%. The mean ratings of untreated trees, SilMatrix and Carbon Defense 

treated trees after three years were 3.5, 0.5 and 0.31 respectively. The preliminary results of this investigation 

indicate that aqueous silicon is a valuable tool in the integrated disease management of DRR in citrus. 

S15P27 

Application of artificial intelligence to the visual diagnosis of quarantine citrus diseases 

Burdyn L. 1 , Garran S.M. 1 , Stegmayer G. 2 , and Milone D.H. 3 

1 Instituto Nacional de Tecnología Agrícola (INTA), Concordia, Argentina; 2 Centro de Investigación en Ingeniería en Sistemas de 

Información (CONICET), Santa Fe, Argentina; and 3 Research Center for Signals, Systems and Computational Intelligence, (FICH-UNL, 

CONICET), Santa Fe, Argentina. lburdyn@correo.inta.gov.ar 

Canker, Scab and Black Spot are endemic diseases in the citrus region of the Uruguay River in Argentina. 

As being quarantine diseases for the European Union, the main export destination. While biochemical 

techniques have greatly improved the sensitivity, accuracy and speed of diagnosis, these are not yet readily 

available in places where diagnosis procedures are necessary. Visual diagnosis currently in use has the main 

constraint that accuracy is limited to the own experiences of persons in charge of performing it. The aim 

of this work has been to incorporate to visual diagnosis procedures new artificial intelligence tools based 

on pattern recognition. These techniques are being applied to the analysis of a database built with all the 

attributes found while defining the whole set of symptoms of these diseases. A communication platform 

already available (Frutic), would allow to any person in charge of the diagnostic procedure the query to the 

intelligent system and its corresponding response be occurring in real time. The database was constructed 

and continues to be updated by the ongoing contribution of symptom descriptions from different varieties 

of tangerines and oranges collected along this region by specialists throughout a campaign. Symptoms are 

visually recognized by using a magnifying glass 20x and described on their different attributes (size, color, 

embossing, texture, etc.). A first version of this system has shown to be effective in a first step of testing. 


S15

S15 

S15P28 

Optimization of copper application schedules for foliar citrus disease management based on fruit 

growth, historical rainfall patterns and copper residue decay 

Zortea T. 1 , Fraisse C.W. 1 , and Dewdney M.M. 2 

1 University of Florida (UF), Agricultural & Biological Engineering, USA; and 2 Citrus Research and Education Center, University of Florida 

(CREC UF), Plant Pathology, USA. mmdewdney@ufl.edu 

Copper applications are essential for foliar citrus disease management in Florida. For effective disease control, 

copper residues need to be maintained above 0.1 µg/cm2. Simulations show the standard timing of copper 

applications every 21 days is insufficient in wet years. To minimize copper coverage gaps for grove operations 

that plan a season’s applications in advance, optimized copper application schedules were developed for early, 

average and late peak bloom. Fifty-five years of historical weather data from the National Weather Service 

Cooperative Observer Program in five counties (Highlands, Hendry, Indian River, Lake and Polk) were used. 

The copper residue decay for each year was calculated from equations for fruit growth, copper deposition 

and residue reduction in the citrus copper application scheduler, a web-based tool to predict residue decay 

(http://agroclimate.org/tools/cudecay/). To test schedules, intervals (days) between applications were varied 

±2 days in a simulation and the best result was rerun until the results converged. Schedules were evaluated 

based on the sum of unprotected days over the 55 years and a percent reduction of days without coverage 

was calculated. For all locations combined there was a 51% reduction from 857 to 420 unprotected days for 

the average bloom and a 19% and 13% reduction for early and late blooms, respectively, with the optimized 

schedules. The greatest improvement occurred in Highlands County with a 57% reduction of unprotected 

days. 

S15P29 

Phytosanitary situation of Chilean citrus industry 

Besoain X., Castro M., Camps R., and López E. 

Pontificia Universidad Católica de Valparaíso (PUCV), Facultad de Agronomía, Chile. xbesoain@ucv.cl 

Chilean citrus industry has experienced a strong growth towards fresh-fruit exports. This situation is partly 

caused by the Japanese market starting to import lemons and the American market mandarins and sweet 

oranges. These markets have been accesed due to Chile’s competitive advantage since it has no pests and 

diseases of world impact such as Fruit Fly (Ceratitis capitata), Citrus Scab (Elsinoë fawcettii), Black Spot 

(Guignardia citricarpa), Citrus Canker (Xanthomonas citri subsp. citri), and Huanglongbing (Candidatus 

Liberibacter spp.). The main diseases affecting citrus fruit in Chilean farms are: Gummosis caused by 

Phytophthora citrophthora and P. hibernalis, Dry Root Rot caused by Fusarium solani, leaf and fruit spots 

caused by Alternaria species. In the post-harvest period, the diseases are: Gray Mold caused by Botrytis cinerea 

(also in pre-harvest), Green Mold and Blue Mold by Penicillium species, Sour Rot by Geotrichum candidum 

and Black Pit by Pseudomonas syringae pv. syringae. Regarding nematodes, Tylenchulus semipenetrans has 

caused considerable damages. Some of the virus diseases include Cachexia (CCaVd) affecting both lemon 

trees and mandarins and Tristeza, only stem pitting syndrome caused by severe isolates of Citrus tristeza virus 

(CTV) affecting grapefruit varieties located in the Pica oasis (Tarapaca Region). The main pests are the Chilean 

False Red Mite (Brevipalpus chilensis), Citrus Red Spider Mite (Panonychus citri), the Pseudococcidae with 

predominant species, Olive Black Scale (Saissetia oleae), Soft Scale (Coccus hesperidum) and Wooly Whitefly 

(Aleurothrixus floccosus). 

S15P30 

Storage technology for conservation of seeds of citrus rootstocks 

Nascimento L.M., Moreira J., Brito M.C.R., Brito P.C.N., and Sanches J.M. 

Centro de Citricultura Sylvio Moreira, Brazil. lenice@centrodecitricultura.br 

This study evaluated Xtend packaging and several fungicide treatments to improve the conservation of seeds 

of ‘Swingle’ citrumelo and lemon ‘Cravo’. Seeds of ‘Swingle’ citrumelo were harvested, washed, and divided 


into two groups: one dried in the shade for four hours (77%) and the other dried with forced air for 72 hours (54 

%). Seeds of lemon ‘Cravo’ were dried in the shade at room temperature for four hours (71%). Three fungicide 

pretreatments were evaluated: 1) fungicide dip (imazalil- 2mL/L) for two minutes; 2) fungicide spray (captan- 

0.5g/L); 3) fungicide dip (imazalil- 1mL/L) for two minutes followed by fungicide spray (captan- 0.5g/L) after 

drying. Treated seeds were divided in lots of 200g, packed in common plastic bags or micro perforated Xtend 

polyethylene bags, and further stored in cold chamber at 5°C and 70% HR. Seed viability in each treatment 

was evaluated by periodic sowing for 10 months and the percentage of germinated seeds was calculated. 

Seed weight loss during storage was also evaluated. The packaging Xtend showed promising results for the 

storage of seeds of ‘Swingle’ citrumelo and lemon ‘Cravo’, compared with the package currently used in citrus 

nurseries. Seed longevity was improved, without reducing seed germination, and the appearance of mold 

fungi was prevented. 

S15P31 

Morphological and molecular diversity of Phytophthora nicotianae strains isolated from citrus 

plantations in Cuba 

Llauger R., Coto O., Peña M., Zamora V., and Collazo C. 

Instituto de Investigaciones en Fruticultura Tropical, Cuba. direccion@iift.cu 

A collection of Phytophthora spp. isolates was built with strains collected from citrus plants showing symptoms 

of Gummosis. Sampled areas belong to two of the most important Cuban citrus enterprises (Jagüey Grande 

and Ceiba del Agua). Eight P. nicotianae strains isolated from citrus plants were identified considering 

sporangia length and width and its ratio. A P. nicotianae strain isolated from mango and a well characterized 

strain isolated from citrus plantation in Brazil were used for comparative purpose. Only two strains were 

identical in the cluster analysis done based on the sporangia traits measured and a morphological diversity 

was observed between Cuban P. nicotianae isolates obtained from citrus. Sporangia were variable in shape, 

mostly ovoid-ellipsoid, obpyriform, spherical and distorted. Pathogenicity assays showed the capacity of the 

strains to affect Mexican lime fruits and rootstocks plants under in vitro conditions and re-isolation of the 

pathogens were done from infected fruits. Molecular identification using primers pairs Pn5B/Pn6 specific 

to P. nicotianae confirmed the previous morphological identification. The sequences of amplified products 

obtained using ITS5/ITS4 primers pairs with DNA template of four of the strains were compared in the NCBI 

Genbank- using BLAST and confirmed the identification as P. nicotianae isolates and the diversity of the 

Cuban strains. Those sequences were included in the NCBI Genbank with the accession numbers: GUO73388, 

GUO73387, GUO73392 and GUO73389. 


S15

Session 16 

ENTOMOLOGY AND PEST CONTROL 

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S16O01 

The status of citrus IPM in California 

Grafton-Cardwell E. E. 

University of California Riverside (UCR), Entomology, USA. eegraftoncardwell@ucanr.edu 

Citrus is grown in 4 distinct regions of California and climatic differences influence the citrus varieties grown 

and the pests and natural enemies that develop. The heaviest insecticide treatments occur in the San Joaquin 

Valley where extremes of heat and cold reduce the efficacy of natural enemies. In the San Joaquin Valley, citrus 

thrips Scirtothrips citri and California red scale Aonidiella aurantii have been primary pests for many decades. 

Forktailed bush katydid Scudderia furcata and citricola scale Coccus pseudomagnoliarum became primary 

pests when selective insecticides replaced organophosphate and carbamate insecticides. San Joaquin Valley 

growers maintain their integrated pest management (IPM) program by utilizing low rates of pyrethroids or 

organophosphate insecticides for katydids and applying organophosphates for citricola scale in alternate years 

– resulting in an average of 3-4 treatments for all pests per year. In 2008, the Asian citrus psyllid, Diaphorina 

citri, was discovered and in 2012 huanglongbing disease was found in California. While the majority of find 

sites of the psyllid have been in residential areas of the state, it is expected that the pest and disease will 

become established in commercial citrus in the near future. Because the disease is difficult to detect when 

trees first become infected and there is no cure for the disease, psyllid population reduction in combination 

with infected tree removal is currently the most effective strategy for preventing disease spread. Because 

the most effective treatments for Asian citrus psyllid are broad spectrum in nature, California citrus IPM 

will experience major disruptions. Regional differences in the risk of Asian citrus psyllid and huanglongbing 

establishment and the impact of treatments for the psyllid on the IPM program are discussed. 

S16O02 

The status of citrus IPM in South Africa 

Grout T.G. 

Citrus Research International (CRI), Nelspruit, South Africa. tg@cri.co.za 

Four years ago citrus IPM in South Africa was largely defined by the use of biorational control strategies such as 

microbial control, sterile insect release, mating disruption, attract-and-kill and soil- and stem-applied systemics. 

This is still the case but pressure from export markets on quarantine pests and diseases has increased, together 

with further residue restrictions. Due to concerns about citrus black spot, Guignardia citricarpa, mancozeb 

applications have increased in the Eastern Cape province and are likely responsible for a decline in numbers of the 

phytoseiid mite Euseius addoensis. This has resulted in greater populations of citrus thrips, Scirtothrips aurantii, 

early in the season and led to the use of longer-residual thripicides such as chlorfenapyr. This product is harmful to 

both phytoseiids and hymenopterous parasitoids of quarantine pests such as certain mealybug species and false 

codling moth (FCM), Thaumatotibia leucotreta. Attempts to redress these imbalances are sometimes made by 

releasing the FCM parasitoid Trichogrammatoidea cryptophlebiae and Coccidoxenoides perminutus for mealybug, 

but the latter is not very effective against indigenous mealybug species. Although California red scale (CRS), 

Aonidiella aurantii, is not a quarantine pest for most export markets, it must be controlled preventively where 

biological control is compromised by disruptive thripicides. This requirement, coupled with the increased price 

of spray oil, has resulted in widespread use of generic imidacloprid SC formulations as soil drenches. Although 

spirotetramat was recently registered in South Africa for the control of CRS and it appears to be IPM-compatible, 

its cost is high relative to other scalicides. The only new citrus pest that has become established in the last four 

years is the woolly whitefly, Aleurothrixus floccosus. The fruit fly Bactrocera invadens has spread throughout the 

rest of Africa south of the Sahara but is not yet established in South Africa. 

S16O03 

Integrated pest management in Spanish citrus: current status of biological control. 

Urbaneja A. 1 , Tena A. 1 , and Jacas J.A. 2 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Protección Vegetal y Biotecnología, Spain; and 2 Universitat Jaume I (UJI), 

Cièncias Agràries i del Medi Natural, Spain. aurbaneja@ivia.es 

Biological control has been and will definitively continue to be an increasingly important part of citrus crop 

protection practices in Spain and elsewhere. Classical Biological Control (BC) has been actively practiced in 


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Spanish citrus orchards for many decades. Most of the citrus pests occurring in Spain at present are under 

satisfactory natural BC, either by indigenous or introduced natural enemies However, a few key pests are not 

controlled by natural enemies. The management of these species has been traditionally based on chemical 

control. Nevertheless, recent restrictions on pesticide usage within the EU have led to a renewed interest on 

alternative BC strategies. Present trends indicate that augmentative and conservation BC will probably play 

an increasing role in the Spanish citrus industry. Additionally, strategies aimed at the conservation of native 

natural enemies of all these pests are in progress. 

S16O04 

Status of citrus IPM in the Southern Mediterranean basin (North Africa): case of Morocco 

Mazih A. 

Institut Agronomique & Vétérinaire Hassan II (IAVHII), Plant Protection, Morocco. ahmedmazih@gmail.com 

More than 30 phytophagous arthropods and snail species have been reported on citrus in Morocco. 

Hemiptera represents the largest number of pest species. These include armored scales, soft scales, 

whiteflies, aphids, mealybugs and leafhoppers. The remaining, are represented by the Med fruitfly, 

Lepidoptera and mites species. The key pests around which control strategies pivot are Mediterranean 

fruit fly,-Ceratitis-capitata-Wiedemann (Diptera: Tephritidae.), California red scale,-Aonidiella-aurantii- 

Maskell (Hemiptera: Diaspididae), mites mainly citrus red mite, Panonychus-citri-McGregor (Acarina: 

Tetranychidae), and the citrus leafminer,-Phyllocnistis-citrella-Stainton (Lepidoptera: Gracilariidae). The 

outbreak of some secondary pests during last years (e.g.-Icerya-purchase Mask (Hemiptera: Margarodidae) 

could be interpreted as the secondary effects of some pesticides, used against key pests, to predatory 

Vedalia beetle-Rodolia-cardinalis Mulsant (Coleoptera: Coccinellidae). In addition, the recent invasion of 

a new mite species-Eutetranychus-orientalis-Klein (Acari: Tetranychidae), recorded for the first time in 

2008, became a big concern, because of its rapid spreading and huge number of generations that often 

necessitate frequent sprays. The most effective products used are mineral oils or sulphur. Up to now, pest 

management in Moroccan orchards still heavily relies on chemical control. However, the implementation 

of ecological methods is slowly taking place. Some have already been developed by research, and could 

be made ready for use in practice, in order to meet the new requirements of the market regarding fruit 

quality, environment, health, and the good agricultural practices. Thus, biological control is in progress and 

alternative methods to chemical control such SIT are underway. 

S16O05 

Integrated Pest and Disease Management in New Zealand- progress,changes and challenges 

since 2004. 

Pyle K.R. 1 , and Jamieson L.E. 2 

1Pyle Orchards and Consulting Pty Ltd, New Zealand; and 2The New Zealand Institute for Plant and Food Research Limited, New 

Zealand. kpyle@xtra.co.nz 

A three year integrated pest and disease management research programme financed by the New Zealand 

government and citrus growers ended in 2005. We give an overview of the key results and the changes and 

challenges since then. The Australian citrus whitefly Orchamoplatus citri (Hemiptera:Aleyrodidae) was first 

detected in New Zealand in 2000 and it spread to all growing areas by 2006.It has resulted in significant changes 

to programmes including additional insecticide sprays. Its phenology, economic importance and chemical 

control strategies are outlined. The prospect for biological control using imported parasitoids from field 

surveys in Australia is described. In lemons, the focus has been on the citrus flower moth Prays nephelomima 

(Lepidoptera: Praydidae) which causes rind spotting and yield reduction, mainly on the YenBen lemon. The 

pest’s phenology, susceptibility to insecticides, and the response to mating disruption trials using 500 to 1000 

dispensers per hectare containing the female sex pheromone are described. Further work is planned using 

lure and kill techniques. Citrus disease research has focused on understanding the disease cycle and control 

of anthracnose (Colletotrichum gloeosporioides) a pre-harvest disease of Satsuma mandarins. 


S16O06 

Progress toward integrated management of Asian Citrus Psyllid in Florida 

Stansly P.A. 

University of Florida (IFAS), SW Florida Research and Education Center, USA. pstansly@ufl.edu 

Asian citrus psyllid (ACP) Diaphorina citri was first detected in Florida in 1998 and quickly spread throughout the 

state, followed in 2005 by huanglongbing (HLB) or citrus greening disease vectored by ACP. High incidence of 

HLB was soon found in many citrus orchards, rendering the recommended practice of removing symptomatic 

trees impractical and leaving vector control as the principal means of HLB management. Two important early 

advances were the “stem tap” technique for rapid monitoring of ACP populations and the “dormant spray” 

that provided effective suppression of overwintering ACP adults. Extensive field testing furnished a suite of 

effective broad-spectrum and selective contact insecticides for foliar application and systemic insecticides 

used as soil drenches to protect young trees. Foliar nutrient programs have proved effective in mitigating 

impact of the disease on mature tree health and productivity when coupled with ACP control, even where HLB 

incidence is high. Area wide cooperative spray programs were organized and executed, and their effectiveness 

documented by statewide monitoring of over 5,000 citrus blocks at 3-week intervals using the tap sample. 

These measures have enabled the Florida citrus industry to maintain viability in the face of HLB, thanks in part 

to a favorable market which has so far covered additional costs. Present efforts are directed at refining and 

improving the program by definition of economic thresholds, better timing and selectivity of spray programs, 

and integration with biological and cultural strategies such as mass release of the parasitoid Tamarixia radiata 

and UV reflective mulches to better protect young plantings. 

S16O07 

Perspective of the Indonesian Citriculture in the Presence of Huanglongbing Disease 

Supriyanto A.S, and Nurhadi N. 

Balai Penelitian Tanaman Jeruk dan Buah Subtropika (Balitjestro), Agriculture, Indonesia. arry_supriyanto@yahoo.com 

Citrus is one of the most important horticultural crops in Indonesia, with a production area of around 57,083 

hectares produced 2,028,904 tons. Mandarins and tangerines are the main citrus grown (95.5%), and others 

such as; pummelo, oranges, limes and lemons represent less than 4,5%. Citrus import during the last decade 

showed a significant increase of about 96 tons in 2000 to 193,462 tons in 2011 with a value of US $53,000 

and of US $171,000,000 respectively, placing Indonesia as the eigth citrus imported country of the world 

and the biggest one in Asia. Citrus plantations in Indonesia can not be avoided from the threat of pests and 

diseases complex, particularly Huanglongbing disease (HLB) that proven causes degeneration of tree growth, 

declining productivity and quality, death; and even threaten the sustainability of the citrus agribusiness in 

citrus plantations of Indonesia. The results of HLB disease epidemic research in the last 10 years provide 

a more comprehensive understanding of: 1) the interactive relationship between the citrus pathogen HLB 

vector Diaphorina citri Kuw. (Hemiptera: Psyllidae) the rate of disease progression of citrus HLB, 3) the spread 

pattern of disease by D. citri in the field, and 4) factors which influence the rate of disease progression and 

spread of HLB in the field. This information is expected to provide more comprehensive understanding of 

how to control HLB properly in the citrus grower situation in Indonesia. This paper provide information and 

discussion dealt with the implications of HLB epidemic studies results and its contribution to the components 

of HLB disease epidemics through the concept of ‘toward precision farming for sustainable citrus health’. 

S16O08 

Nontarget effects of cultural practices to manage the bacterial disease huanglongbing on soil 

food webs that affect the insect pest Diaprepes abbreviatus 

Campos-Herrera R. 1 , El-Borai F.E. 2 , Schumann A. 2 , and Duncan L. W. 2 

1 Instituto de Ciencias Agrarias (ICA-CSIC), Contaminación Ambiental, Spain; and 2 University of Florida, Citrus Research and Education 

Center (UF-CREC), Entomology and Nematology, United States (US). r.camposherrera@ufl.edu 

The ‘Advanced Citriculture Production System’ (ACPS) can mitigate the impact of the devastating bacterial disease 

huanglongbing (HLB) by bringing citrus trees into production more quickly than conventional citriculture methods. 


S16

S16 

Daily fertigation required by ACPS changes soil physico-chemical properties compared to those in conventionally 

managed orchards. Real-time PCR was used in a field trial to investigate the effects of ACPS compared to 

conventional grower practices (G) on more than a dozen microorganisms in soil food webs that affect larvae 

of a major arthropod pest of citrus, Diaprepes abbreviatus (Diaprepes root weevil, DRW). A second treatment 

involves the use of polypropylene mulch as a barrier to DRW entering or exiting soil. To date, greater numbers 

of the EPN Steinernema scapterisci and more nematophagous fungi (Catenaria sp. and Paecilomyces lilacinus) 

were recovered from bare compared to mulched soil (P < 0.05). Steinernematid entomopathogenic nematodes 

(EPNs) were more prevalent in G, whereas more Heterorhabditis indica were detected in ACPS (P < 0.05). ACPS 

increased citrus fibrous roots and the numbers of plant parasitic nematodes, free living nematodes and DRW 

emerging from soil (P < 0.05). These results demonstrate the need to understand how the management tactics 

used to mitigate HLB might be modified to avoid exacerbating other serious biotic perturbations to tree health. 

S16O09 

Protection of young trees from HLB through disruption of Diaphorina citri (Kuwayama) feeding 

behavior. 

Rogers M.E., Ebert T.A., Kim K.D., and Weaver C.E. 

University of Florida, Citrus Research & Education Center (UFCREC), Entomology and Nematology, United States. mrgrs@ufl.edu 

The long-term economic viability of a citrus grove is dependent on the ability to replant new trees and bring 

those trees into fruit production. In areas where HLB is endemic, young trees that become infected with the HLB 

pathogen are unlikely to become productive fruit-bearing trees. Thus, it is of utmost importance to determine 

ways to prevent young trees from becoming infected with the HLB pathogen. Using an electrical penetration 

graph (EPG) monitor, we determined the ability (and duration) of foliar and soil-applied insecticides to disrupt 

the feeding behaviors of D. citri postulated to be responsible for successful pathogen transmission. In the 

field, caging studies with adult D. citri were conducted every 3 months to determine the residual activity of 

selected insecticides (in terms of direct insect mortality) under field conditions during the different seasons 

of the year. Results of this work were then used to design a multi-year field trial to validate whether certain 

season-long insecticide programs can prevent young trees from becoming infected with the HLB pathogen. 

Immediately following the planting of a 4-ha block of ‘Valencia’ orange, replicated plots were established and 

assigned to one of six insecticide programs. Biweekly psyllid counts were made for each plot and trees were 

tested every 3 months for the presence of the HLB pathogen. Results will be discussed in terms of developing 

pest management programs to protect young tree plantings from HLB. 

S16O10 

Effect of UV-blocking plastic films on plant location and spread of the Asian Citrus Psyllid, 

Diaphorina citri Kuwayama (Hemiptera: Psyllidae) on citrus. 

Miranda M.P. 1 , Marques R.N. 1 , Santos F.L. 1 , Felippe M.R. 1 , Moreno A. 2 , and Fereres A2 . 

1Fundecitrus (Fundecitrus), Scientific Department, Brazil; and 2Institute of Agricultural Sciences (I.C.A), Crop Protection, Spain. 

mpmiranda@fundecitrus.com.br 

Diaphorina citri (ACP) is a major pest of citrus worldwide as it transmits Huanglongbing (HLB). Vision, behavior 

and performance of insect pests can be manipulated by using UV-blocking materials. Thus, the aim of our 

study was to evaluate how UV-blocking films affect the spread and host plant finding ability of ACP. Screen 

houses (5m x 2.5m x 2m) either covered with a UV-blocking film (98.9% UV-block) or with a non UV-blocking 

film (control) were evaluated. In a first trial, 100 ACP adults were released at the center of each screen house 

to assess their ability to locate citrus plants arranged around the release point. In a second trial, 100 ACP 

adults were released at one end of the screen house to assess their ability to spread along citrus plants placed 

in 3 rows of 4 plants spaced 1 m apart. In both trials, the number of psyllids/plant at different time intervals 

was counted. A low percentage of psyllids were able to locate citrus plants under the UV-blocking film: 9% 

(UV-blocking) and 60% (non UV-blocking) in the first trial, and 2.5% (UV-blocking) and 46% (non UV-blocking), 

in the second trial. This represents a 90% reduction in the ability of psyllids to find their host plants. In the 

second trial, psyllids concentrated mainly in the first rows under the UV-blocking films whereas distribution 


was uniform under the non-UV-blocking films. Our results show that UV-blocking films can effectively limit 

the spread of ACP in citrus grown in enclosed environments. 

S16O11 

Ontogenic variation in citrus flush shoots and its relation with host plant finding and acceptance 

by Asian Citrus Psyllid (Hemiptera: Psyllidae) 

Setamou M. 1 , and Patt J. M. 2 

1 Texas A & M University-Kingsville Citrus Center (TAMUK-CC), Agriculture, Agribusiness and Environmental Sciences, USA; and 2 U.S. 

Horticultural Research Laboratory (USDA-USHRL), Horticulture and Breeding Research, USA. mamoudou.setamou@tamuk.edu 

The Asian citrus psyllid, Diaphorina citri (Hemiptera: Psyllidae) is a destructive insect mainly because it 

vectors the bacterial pathogens that cause the deadly and incurable citrus greening disease. Diaphorina citri 

adult females lay eggs and immature development occurs exclusively on new flush shoots of their Rutaceae 

host plants. Although citrus trees are evergreen vegetation that holds green foliage all year round, D. citri 

is particularly abundant in citrus groves when new flush shoots are present. Thus, population dynamics of 

this pest are strongly determined by flush cycles of citrus trees. New flush shoots have distinctive physical 

and chemical characteristics that may facilitate host finding by adult psyllids and their suitability for psyllid 

oviposition and immature development. Consistent with this hypothesis, D. citri adults preferentially selected 

younger flush shoots over mature ones for feeding and oviposition. Appearance of young flush shoots as 

measured by their spectral reflectance, their softness and volatile composition provided evidence of their 

roles in nutritional ecology of D. citri. 

S16O12 

Targeting juvenile hormone metabolic genes in the Asian citrus psyllid (Diaphorina citri) as a 

strategy to reduce the spread of citrus greening disease. 

Van Ekert E. 1 , Borovsky D. 2 , Powell C. A. 3 , Cave R. D. 1 , Alessandro R. T. 4 , and Shatters R. G. 4 

1 Indian River Research and Education Center, University of Florida, Entomology and Nematology, USA; 2 Borovsky consulting, Vero 

Beach, FL, USA; 3 Indian River Research and Education Center, University of Florida, Plant Pathology, USA; and 4 US Horticultural 

Research Laboratory, USDA - ARS, USA. belgica@ufl.edu 

Diaphorina citri Kuwayama, the Asian Citrus Psyllid (ACP), is a devastating citrus pest due to its transmission 

of a phloem-limited bacterial pathogen, Candidatus Liberibacter asiaticus Jagoueix that causes citrus 

greening. Psyllid control is a major part of effective greening disease management, and our research targets 

perturbation of insect juvenile hormone metabolism as a new psyllid control strategy. Previous studies have 

shown that application of a juvenile hormone (JH) analogue, pyriproxyfen, produces ovicidal/nymphicidal 

effects, morphological abnormalities, and reduced fecundity in ACP adults. These observations prompted 

us to identify JH biosynthetic and degradative pathways as targets for biologically-based control strategies, 

including RNA interference, as alternatives to heavy reliance on broad-spectrum pesticides. First, candidate 

genes/cDNAs encoding the JH metabolic enzymes, juvenile hormone acid methyl transferase (JHAMT) and 

juvenile hormone esterase, were identified through computational analysis of the ACP genome. Second, 

JHAMT cDNA was cloned, expressed in E. coli and a functional protein was purified. This JHAMT had a high 

affinity for substrates leading to JHI and JHIII synthesis, making it plausible that both juvenoids are present 

in the ACP. Results are discussed with respect to mechanism(s) of JH biosynthesis/catabolism in the ACP and 

targeting this process as an interdiction point for a biorational ACP control strategy. 

S16O13 

Biological control of red scale on citrus on the central coast of New South Wales. 

Dao H.T. 1 , Beattie G.A.C. 2 , Holford P. 2 , Spooner-Hart R. 2 , Meats A. 3 , and Burgess L. 3 

1 Plant Protection Research Institute (PPRI), Vietnam; 2 University of Western Sydney (UWS), Australia; and 3 University of Sydney, 

Australia. daothihang@hotmail.com 

Most studies on the ecology and biological control of California Red Scale (Aonidiella aurantii) in citrus orchards 

have been undertaken in warm dry regions where species of Aphytis, particularly A. melinus, are viewed as the 


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most important of a narrow-range of natural enemies. Our research was undertaken in unsprayed orchards on 

the relatively humid central coast of New South Wales where three annual generations of the scale and a wide 

range of key natural enemies, comprising five parasitoids, four native coccinellids, and six entomopathogenic 

fungi, occur. Scale populations were maintained below economic thresholds despite marked variation in levels 

of parasitism and incidence of predators and entomopathogens among study orchards. Winter temperatures 

and natural enemy activity in summer-autumn were the key factors limiting abundance of the scale. The most 

important natural enemy was the steelblue ladybird, Halmus chalybeus. Incidence of the five parasitoids, A. 

chrysomphali, A. melinus, Encarsia citrina, E. perniciosi and Comperiella bifasciata, varied among orchards. Two 

strains of A. melinus, one of uncertain origin, were recorded. E. citrina and E. perniciosi, both of unknown origin, 

played important roles. Parasitism was not density-dependent. Competitive displacement was not evident. 

Intraguild predation by Aphytis on Encarsia was rare. Three fungi had not been previously recorded in Australia. 

Current diversity and abundance of the fungi may stem from reduced use of fungicides. 

S16O14 

Sugar provisions improve fitness and efficacy of the parasitoid Aphytis melinus in the field. 

Tena A. 1 , Cano D. 2 , Pekas A. 3 , Wäckers F. 4 , and Urbaneja A. 1 

1 instituto Valenciano De Investigaciones Agrarias (IVIA), Protección Vegetal y Biotecnología. Entomología, Spain; 2 Bioinsumos Agrícolas 

(SAC), PERÚ; 3 Universidad Politécnica de Valencia (UPV), Instituto Agroforestal Mediterráneo, Spain; and 4 Lancaster Environment 

Centre, Lancaster University (ULAN), Centre for Sustainable Agriculture, UK. atena@ivia.es 

Many adult parasitoids depend on sugar-rich foods such as nectar and honeydew to meet their energy 

requirements. We used HPLC (high performance liquid chromatograph) analyses to assess the sugar 

reserves (total sugar per parasitoid) and honeydew consumption of individual field collected Aphytis melinus 

parasitoids, the most successful biological control agent of California Red Scale Aonidiella aurantii. The number 

of honeydew producers was also measured when A. melinus were collected. Our data show that A. melinus, 

whose host does not produce honeydew, fed commonly on honeydew from other abundant hemipterans 

in spring and summer. However, when the number of honeydew producers decreased, as occurred in fall, 

less than 20% of A. melinus were found to have fed on honeydew, and their average total sugar content 

was reduced three-fold. In a second assay, we determined whether the addition of sugar provisions might 

improve the fitness and performance of A. melinus when honeydew producers were scarce. We compared 

sugar reserves of A. melinus using HPLC analysis, and evaluated population density, parasitism rates on A. 

aurantii and migration in trees with and without sugar subsidies. Our results showed that the number of adult 

A. melinus per tree, migration, parasitism rates and the number of parasitoids classified as sugar fed (those 

that had previously fed on sugars) were all greater in trees where sugars were added. 

S16O15 

Ground cover management in citrus affects the biological control of aphids. 

Gómez-Marco F. 1 , Tena A. 1 , Jacas J.A. 2 , and Urbaneja A. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Unidad Asociada de Entomología UJI-IVIA; Departamento de Entomología, 

Spain; and 2 Universitat Jaume I (UJI), Unitat Associada d’Entomologia IVIA-UJI, Spain. fmgomez@ivia.es 

The citrus aphids, Aphis spiraecola Patch and A. gossypii Glover (Hemiptera: Aphididae), are key pests of citrus 

clementine in Spain. A rich complex of natural enemies (NE) exploits these two species. However, NE usually 

arrive too late, when aphid population have exceeded economical thresholds. Hence, successful biological 

control should be based on anticipating the arrival of NE. This could be achieved by use of reservoir plants. 

Festuca arundinacea Schreb has proved as a suitable ground cover enhancing biological control of different 

citrus pests, as Tetranychus urticae Koch and Ceratitis capitata (Wied.). We have compared the dynamics of 

aphid colonies for two consecutive seasons in orchards with a F. arundinacea ground cover versus bare soil, 

which is the traditional citrus ground management. Aphid colonies were smaller and lasted shorter in trees 

associated with F. arundinacea than in those grown on bare soil. These differences have been attributed to 

an earlier appearance of aphid NE in F. arundinacea, which were much more abundant than in bare soil. The 

final cause of these differences is probably related to the presence of alternative prey/host in the grass (cereal 

specific aphid species). 


S16O16 

Field evaluation of some pesticides and biological control against citrus mealybug Planococcus 

citri Risso (Hemiptera:Pseudococcidae) 

Kararacoglu M. 1 , Kutuk H. 1 , Tufekli M. 1 , Satar G. 2 , and Yarpuzlu F. 1 

1 Biological Control Research Station, Turkey; and 2 Department of Plant Protection, Faculty of Agriculture, University of Cukurova, 

Turkey. h_kutuk@hotmail.com 

This study was conducted to compare efficiency of some insecticide and biological control against citrus 

mealybug, Planococcus citri Risso (Hemiptera:Pseudococcidae), caused important economic losses in recent 

years in the Mediterranian region of Turkey. It was investigated at 23 different citrus orchards ranged 0.6- 

17 ha in Finike districtive of Antalya province in 2011. Summer oil, Chloropyrifos-ethyl, Spirotetramat and 

biological control agents, (Cryptolaemus monrozieri Mulsant and Leptomastix dactylopii How.) were applied 

under farmer conditions. Biological control agent was sampeled by stenier funnel and made visual observation 

of 100 fruit for infestation rate 30-45 days after application. There weren’t found any big differences between 

insecticide application and biological control. While the lowest infestation value was Summer oil (% 5.91); 

Spirotetramat (% 6.88), Chloropyriphos-ethyl (%7.69) and biological control (% 8.66) fallowed it. The highest 

average number of predator (biological control agent) was determined as 20.57 individulas per steiner funnel 

for biological control applied citrus orchard, followed by summer oil as 4.25 individuals, spirotetramat as 2.67 

individuals. But no biological control agent observed at Chloropyriphos-ethyl applied citrus orchards. Because 

of possibility of fitotoxity effect of summer oil at hot weather condition, spirotetramat looks an alternative to 

biological control or has a change in IPM application for managing citrus mealybug. 

S16O17 

Can imidacloprid cause lepidopteran pest repercussions? 

Moore S.D. 1 , Van der Walt R. 2 , Kirkman W. 1 , and Du Preez D. 3 

1 Citrus Research International (CRI), South Africa; 2 Nelson Mandela Metropolitan University (NMMU), Biochemistry and Microbiology, 

South Africa; and 3 Nelson Mandela Metropolitan University (NMMU), Botany, South Africa. seanmoore@cri.co.za 

Imidacloprid has been registered on citrus for the control of California red scale and aphids for many years. 

Higher levels of false codling moth (FCM), Thaumatotibia leucotreta, on citrus have anecdotally been associated 

with the use of systemically applied imidacloprid for a number of years. However, these observations have 

not been scientifically supported until now. Two analytical methods were used to determine the physiological 

effect of imidacloprid on adult female FCM: mass spectrometry for ovarian protein and HPLC for quantifying 

Juvenile Hormone (JHIII) levels. Elevated ovarian protein and JHIII levels were recorded in moths which had 

developed from imidacloprid-treated fruit or diet. Additionally, fecundity of moths which developed from 

imidacloprid-treated fruit was significantly higher than that of moths which had developed on untreated 

fruit. In a field trial, FCM infestation in the imidacloprid-treated half of an orchard was almost double that 

in the untreated half of the orchard. This comparison was reliable, as there were no other differences in the 

pesticide programme and FCM levels in the two halves of the orchard had been almost identical during the 

previous season. This trend was, however, not repeated in a second orchard. Although final repetitions of 

ovarian protein, JHIII, laboratory fecundity studies and studies on field levels of FCM will be conducted, it 

can already be concluded that imidacloprid treatment of citrus trees can lead to elevated levels of FCM in 

orchards. It is possible that the same effect could also occur with other Lepidoptera. 

S16O18 

Ecology and management of Kelly’s Citrus Thrips in Eastern Spain 

Navarro-Campos C. 1 , Pekas A. 2 , Aguilar A. 1 , and Garcia-Marí F. 1 

1 Universidad Politécnica de Valencia (UPV), Instituto Agroforestal del Mediterráneo, Spain; and 2 Biobest Belgium N.V., R&D 

Department, Belgium. crinacam@posgrado.upv.es 

Kelly’s Citrus Thrips (KCT), Pezothrips kellyanus, is a recently reported citrus pest worldwide. In eastern 

Spain citrus KCT was first identified in 2005 and nowadays is the most abundant thrips species found in 


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citrus flowers causing important economic losses due to fruit scarring. We studied different aspects of KCT´s 

biology and ecology in order to improve its management. KCT populations were sampled throughout the 

year in 14 citrus orchards in 2008 and in eight citrus orchards in 2009 and 2010 by sampling citrus flowers, 

fruitlets and mature fruits, as well as employing ground and aerial sticky traps. Additionally, soil samples were 

extracted using Berlese funnels in order to determine the presence and abundance of soil predatory mites. 

KCT individuals were captured in the citrus groves all year round: for the three years of the study the highest 

KCT population density was observed during the petal fall and the beginning of the fruit growing periods. 

Differences in the population density and damage by KCT were observed among years, apparently related with 

air temperature. With the data obtained, the aggregation pattern, sampling plans, and intervention threshold 

for KCT were determined. With respect to soil predatory mites, 15 species from eight families were identified 

being Parasitus americanus and Gaeolaelaps (Hypoaspis) aculeifer the most abundant. Higher populations of 

some predatory mite species were associated with lower fruit damage caused by KCT suggesting potential for 

biological control. 

S16O19 

Monitoring and management of Brevipalpus chilensis Baker (Acarina: Tenuipalpidae) in citrus 

Olivares N. 1 , Vargas R. 1 , and Ripa R. 2 

1 Instituto de Investigaciones Agropecuarias (INIA), CRI, La Cruz, Chile; and 2 Centro de Entomología Aplicada (CEA Ltda.), Chile. 

nolivare@inia.cl 

The mite Brevipalpus chilensis Baker is an endemic phytophagous pest in Chile. It has a wide host range 

including citrus, grapes, custard apple and kiwi. The objective of this study was to evaluate B. chilensis 

population fluctuation in Citrus sinensis, Citrus limon and Citrus reticulata. The studies were conducted 

in three commercial orchards located in Valparaíso Region, Chile. Samples were taken every 15 days from 

lignified and non-lignified branches, fruits, and leaves. The sampled structures that displayed the largest 

abundance of mites were branches and fruits; the mites were not found on citrus leaves. In periods of fruit 

absence, branch monitoring is the most suitable tool for determining the density of B. chilensis. The results 

of this study show that B. chilensis is present all the season on lignified and non-lignified branches. This 

would allow a more precise monitoring and control preventing the migration of the mites towards the fruits. 

With these results we conclude that the optimal integrated management of B. chilensis in citrus orchards 

must include practices such as opening tree canopy by selective pruning, removal of non-harvested fruit, and 

chemical spray applications, one at the beginning of summer plus a second spraying post-harvest. 

S16O20 

Host adaptation of Tetranychus urticae populations in clementine orchards with a Festuca 

arundinacea cover may contribute to its natural control. 

Aguilar-Fenollosa E., Pina T., Gómez-Martínez M.A., Hurtado M.A., and Jacas J.A. 

Universitat Jaume I (UJI), Ciències Agràries i del Medi Natural, Spain. aguilare@uji.es 

Tetranychus urticae Koch (Acari: Tetranychidae) is a key pest of clementine mandarins, Citrus clementina 

Tanaka (Rutaceae), in Spain. This mite is highly polyphagous and can be easily found in clementine orchards, 

both in the trees and in the associated flora. In a previous study we found that the use of a cover of Festuca 

arundinacea Schreber (Poaceae) offered a better regulation of T. urticae populations than either bare soil 

or the traditional wild cover, which included a mix of weed species. We hypothesized that the selection of 

two host races of T. urticae, specialized in F. arundinacea and C. clementina, could partly explain the results 

obtained in field studies (bottom-up regulation). Reciprocal transplant experiments show that sympatric deme 

× host combinations had higher mean fitness values than the allopatric combinations in clementine, but not 

in F. arundinacea, for most of the fitness parameters evaluated in the present study. Because local adaptation 

implies mean deme fitness to be systematically higher for the sympatric deme × habitat combinations than 

for the allopatric ones, these results can be taken as indicative of occurrence of local adaptation in T. urticae. 

Molecular genetics analyses with microsatellite markers support this conclusion and indicate that host 

adaptation of T. urticae found in our system may indeed contribute to a better natural regulation of this mite. 


S16P01 

Analysis of population trends of Citrus pests from an area-wide field survey and monitoring 

network established in eastern Spain 


Universitat Politècnica de València (UPV), Instituto Agroforestal Mediterráneo, Spain. fgarciam@eaf.upv.es 

The establishment of scientifically sound warning, forecasting and early diagnosis systems is one of the 

priorities established by EU directives for pest management. Programs of field survey and monitoring 

generate also a large amount of information which can be useful to identify and study factors which influence 

pest populations. We present results of an area-wide survey and monitoring network established by the 

autonomic Government of the Comunitat Valenciana in eastern Spain citrus crops between 2004 and 2009 

for quarantine purposes and to assist farmer in pest management decisions. Four hundred orchards were 

monitored biweekly all along the year, determining population levels of the most important pests. Population 

trends and patterns of change in pest abundance were determined along the season each year, from year to 

year, among citrus species and geographically, between different regions of the area surveyed. Depending 

on the species or group of arthropod, factors as macro and microclimate, biological control, plant species 

preference, cultural practices or interactions between these factors, were considered responsible for the 

demographic patterns observed. 

S16P02 

Arthropod pest composition and farmers’ perceptions of pest and disease problems on citrus in 

Kenya 

Ekesi S. 

International Centre of Insect Physiology & Ecology (ICIPE), Plant Health, Nairobi, Kenya. sekesi@icipe.org 

A survey was conducted in citrus orchards in lowland and highland areas of Kenya to assess arthropod pest 

composition and damage on three citrus species as well as farmers’ perceptions of pest and disease problems 

in their farms. Various arthropod pests were identified attacking citrus. In the lowlands, fruit flies infested 

(38.4%) of the fruits, false codling moth (FCM) (22.6%), and citrus rust mite (CRM) (7.6%). In the highlands, 

fruit flies infested 36.4% of fruits, FCM (20.2%) and CRM (9.4%). The major leaf feeders in the lowlands were 

scales that infested a mean of 18.1% of trees, aphids (16.2%), whiteflies (12.6%), swallowtail butterfly larvae 

(SB) (11.8%), thrips (11.4%) and mealybugs (4.8%). In the highlands, African citrus psyllid (ACP) infested a 

mean of 33.2% of the trees, followed by scales (27.1%), whiteflies (15.4%), thrips (12.1%), aphids (10.1%), 

SB (9.8%) and leafminers (4.2%). Among the arthropod pests, farmers ranked fruit flies at 84.2%, and FCM, 

scales and ACP at a mean of 66.3% as the major pest constraint in citrus production. Greening ranked highest 

(85.4%) among diseases followed by fruit and leaf spot (72.4%) and citrus tristeza virus (44.5%). Only 24.6% 

of farmers used some form of chemical insecticide (modern or traditional) in citrus production, largely due to 

lack of capital, efficacy or availability of the products. 

S16P03 

Thresholds for HLB vector control in infected commercial citrus and compatibility with biological 

control. 

Monzó C. 1 , Stansly P.A. 1 , and Urbaneja A. 2 

1University of Florida (IFAS), SWFREC, USA; and 2Instituto Valenciano de Investigaciones Agrarias (IVIA), Entomology, Spain. 

aurbaneja@ivia.es 

Control of the HLB vector, Diaphorina citri Kuwayama, is considered a basic component for management this 

disease, even in a high HLB incidence scenario. Such control is mostly chemically oriented. However, overuse 

of insecticides would increase costs and be incompatible with biological control. Establishment of economic 

thresholds for psyllid control under different price scenarios could optimize returns on investment. Two 

3-year experiments are being conducted in commercial orange blocks with high HLB incidence. Experimental 


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design is RCB with 4 treatments and 4 replicates: no insecticide, calendar applications, insecticide applications 

according to a threshold of 0.2 psyllids/stem tap sample, and applications according to a 0.7 threshold. Vector 

populations are monitored biweekly by tap sampling. Differences in vector abundance among treatments 

are being correlated to HLB infection levels estimated by Q-PCR and most importantly, to fruit yields. 

Consequences of each vector control strategy on beneficial arthropod fauna are also being evaluated, as well 

as potential negative impacts on biological control processes in the crop. After two years, a yield increase was 

observed with the calendar treatment, but so far additional costs would require high juice prices scenarios to 

be sustainable. Negative impacts of calendar sprays on biological control of mites and leafminers have also 

been observed 

S16P04 

Development of the Huaglongbing (HLB) vector, Diaphorina citri Kuwayama, 1908 (Hemiptera: 

Psyllidae), in different host plants. 

Alves G.R., Diniz A.J.F., Lima A.A., Vieira J.M., and Parra J.R.P. 

Escola Superior de Agricultura Luiz de Queiroz - Universidade de São Paulo (Esalq/USP), Entomologia e Acarologia, Brazil. 

gustavo_ralves@yahoo.com.br 

Huanglongbing (HLB) or greening is considered the most important Citrus disease in the world. In Brazil, it is 

transmitted by the Asian citrus psyllid Diaphorina citri. Knowledge on the life cycle of D. citri in natural and 

non-citrus hosts may help Integrated Pest Management in citrus. The objective of this work was to evaluate 

the effect of the most common cultivars grown in the state of São Paulo (Hamlin, Pêra, Natal, Valencia and 

Ponkan) and that of the orange Jessamine, Murraya paniculata, used in Brazil as hedgerow and considered 

a very important non-citrus host for this psyllid. D. citri couples were individually confined in cages for egg 

laying during 24 h, under laboratory conditions (temperature: 25±2°C; RH: 60±10%; photophase: 14h). Egg 

hatching and nymph mortality were daily observed until adult emergence. The egg viability ranged from 83.3 

% to 56.8% for Valencia and Hamlin cultivars, respectively. The nymphal viability was also the lowest in the 

Hamlin cultivar (57.4%), with no differences among the other treatments. The highest viability was observed 

in the Valencia cultivar (65.9%) with the lowest in the Hamlin cultivar (32.6%).The life cycle lasted from 18.4 

(Natal) to 17.2 (orange Jessamine) days. 

S16P05 

Agreggation and sampling plans for Diaphorina citri (Hemiptera: Psyllidae) immature stages in 

citrus. 

Asplanato G. 1 , Amuedo S. 1 , and Franco J. 2 

1Facutad de Agronomía - Universidad de la República (FAGRO-UDELAR), Protección Vegetal, Uruguay; and 2Facultad de Agronomía - 

Universidad de la República (FAGRO-UDELAR), Biometría y Estadística, Uruguay. gasplana@fagro.edu.uy 

The Asian Citrus Psyllid Diaphorina citri is an efficient vector of the associated bacteria to Huanglongbing, 

considered the most destructive citrus disease in the world. In Uruguay, the psyllid was reported in 1991 but 

the disease has not been discovered yet. Studies were conducted to determine the distribution pattern of D. 

citri eggs and nymphs on flush shoots and to develop reliable sampling plans. The samplings were carried out 

from 2006 to 2009 in five citrus orchards located in the main citrus growing region of Uruguay. Taylor´s power 

law was appropriate and adequate to describe the variance-mean relationship of all D. citri development 

stages on the five orchards. The dispersion index b from Taylor’s power law did not vary among orchards and 

development stages. Data from all orchards were pooled and common regression slope for eggs and nymphs 

were estimated. The distribution pattern of immature stages was aggregated among flush shoots as indicated 

by the dispersion index b=1.42, that was significantly > 1. The minimum sample size to estimate densities 

above five immature stages (eggs nymphs) per flush shoot was 175 flushes for a precision level of 0.25, 

appropriate for management decisions. To provide a quick estimation of D. citri in citrus orchards, a presence 

– absence sampling plan was evaluated. 


S16P06 

Use of oils to control the Asian Citrus Psyllid (Diaphorina citri) in Mexican lime under dry tropic 

conditions in Mexico 

Orozco-Santos M., Velázquez-Monreal J.J., García-Mariscal K., Manzanilla-Ramírez M.A., Carrillo-Medrano S.H., and 

Robles-González M.M. 

Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias (INIFAP), Campo Experimental Tecomán, Mexico. 

orozco.mario@inifap.gob.mx 

Mexico is the main world producer of Mexican lime (Citrus aurantifolia). The Asian Citrus Psyllid (ACP; Diaphorina 

citri) is the most important pest affecting this citrus species which is the vector of Huanglongbing disease. ACP 

control is based on the use of synthetic insecticides. Although, oils have a long history as insecticides to control 

citrus pests, only a few cases have been reported against D. citri. In this study, the effects of 9 oils against ACP 

were evaluated in Colima, Mexico. Three assays were carried out in trees heavily infested with the insect. One 

foliar application of each treatment was done on tagged shoots of 4-6 days old. Temperature during application 

was 32 °C±1. Live nymphs were evaluated after the application. In the first test, three doses of the paraffinic oil 

(PureSpray Foliar 22E®: 1, 2 and 3%) reduced ACP population from 9.3-13.2 nymphs/shoot (before application) 

to 0.2-2.7 nymphs (at 7 days). The control registered 11.5 nymphs. In the second and third test, all paraffinic 

oils tested (PureSpray Foliar 22E®, Saf-T-Side®, Apoyador®, Stylet-oil®, and Banasole®), cooking oil (Cristal®), 

petroleum oil (Citrolina) and citrus oil (Oroboost®) showed the lowest infestations of ACP relative to the control. 

At 7 days, oils registered 0.7-3.3 nymphs/shoot, 0.0-1.8 nymphs/shoot were found in the second and third 

tests, respectively. Contrarily, control had 6.1 and 11.6 nymphs/shoot. No oil caused phytotoxicity was observed. 

These results indicate that the oils can be included in programs for ACP control in Mexican lime. 

S16P07 

Seasonal patterns in the proportion of Asian citrus psyllid (Diaphorina citri) carrying Candidatus 

Liberibacter asiaticus. 

Ebert T.A. 1 , Brlansky R.H. 2 , and Rogers M.E. 1 

1 University of Florida - Citrus Research & Education Center (UFCREC), Entomology and Nematology, United States; and 2 University of 

Florida - Citrus Research & Education Center (UFCREC), Plant Pathology, United States. mrgrs@ufl.edu 

Candidatus Liberibacter asiaticus (Las) is the putative causal agent of Huanglongbing disease in Florida citrus 

where pathogen spread occurs by the Asian Citrus Psyllid (Diaphorina citri Kuwayama). Insecticide use to 

control D. citri in attempts to manage the spread of Las occur year-round, resulting in the application of 

up to 12 or more insecticides applications per year. However, it is unknown if there are periods of the year 

when psyllids may be less likely to be carrying Las and thus insecticide applications may not be warranted. To 

determine if there are times of the year when pathogen spread may be less likely to occur, D. citri populations 

at six locations in central Florida and one location in southern Florida were sampled monthly over a 48 month 

period. The proportion of adult D. citri carrying Las was measured using QPCR of pooled samples. Prior to 

DNA extraction, psyllids were sorted by gender and color. Florida Automated Weather Network was used to 

estimate environmental conditions at these locations. Las was present at all times of year, but prevalence was 

highest October through December. Seasonal patterns in sex ratio and color were correlated with weather 

patterns and Las prevalence in D. citri. 

S16P08 

Effectivness of Imidacloprid (Winner) by trunk application for psyllid (Diaphorina citri – 

Hemiptera: Psyllidae) control on citrus. 

Lozano Leonel Junior F. 1 , Soares R.D.J. 1 , and Moraes J.P. 2 

1 BayerCropScience (BCS), Agronomic Development, Brazil; and 2 Escola Superior de Agronomia Luiz de Queiroz (ESALQ), Brazil. 

francisco.lozano@bayer.com 

The citrus psyllid (Diaphorina citri) injures citrus by: (1) distortion and curling of leaves, (2) withdrawal of sap 

from the foliage, and (3) transmission of the bacterium that causes the greening disease (Huanglongbing). 


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Suppression of citrus psyllid populations is recommended for slowing disease spread. The efficacy of the 

Winner® (imidacloprid) by trunk application was tested against the citrus psyllid in plants with different ages. 

This experiment was conducted in a citrus grove of different tree sizes in Bayer CropScience’s Experimental 

Agricultural Station, Paulínia, SP, Brazil. The study block was divided into four replicates within which 7 treatments 

were randomly assigned: (1 – 5) Winner 200 CS (Imidacloprid 200 g/L) at 0.2 g ai/cm trunk diameter in plants of 

2, 5, 10, 15 and 20 cm diameter, (6) Winner 200 SC at 0.3 g ai/cm trunk diameter on 20 cm diameter plants, and 

(7) a blank application as untreated control. Treatments were applied by a spray applicator with the full strength 

product without water, around the whole diameter of the trunk 20 cm below the lowest branches. Psyllid adults 

were confined by sleeve cages to plant shoots and the number of alive adults and nymphs inside the cages 

were later counted to assess efficacy. The interval of the infestations was according the presence of new shoots. 

Efficacy was calculated by the formula of Abbott and the data were transformed using the arcsine square root 

functions and subjected to ANOVA and means compared using Tukey’s test (P < 0.05). -Control was 100% in 

plants of 5 cm diameter but variable results against adults were seen on larger trees.- Nymphs controlled better 

than adults regardless of tree size, with suppression observed up to 214 days. 

S16P09 

Movement of Asian citrus psyllids in HLB-affected and healthy citrus trees 

Cen Y. 1 , Wu F. 1 , Liang G. 1 , Chen J. 2 , Deng X. 3 , and Xia Y. 4 

1 Laboratory of Insect Ecology, South China Agricultural University, China; 2 Crop Diseases, Pests and Genetics Research, San Joaquin 

Valley Agricultural Sciences Center, USDA, USA; 3 Citrus Huanglongbing Research Laboratory, South China Agricultural University, 

China; and 4 Center for Integrated Pest Management, North Carolina State University, USA. cenyj@scau.edu.cn 

Asian Citrus Psyllid (ACP) Diaphorina citri Kuwayama (Hemiptera: Psyllidae) is the vector of Huanglongbing (HLB). 

Diaphorina citri showed different tropism to HLB-infected and healthy citrus trees. The presence or absence of 

new flushes had a significant influence on the movement of ACP in HLB-affected citrus hosts. With new flushes, 

HLB-affected citrus trees were more attractive to adults of ACP. The psyllids fed on the host for a longer time 

period. In the absence of new flushes, psyllids preferred leaves with yellowing symptoms. After feeding for about 

36 hours, psyllids moved to health-looking leaves. This behavior appeared to facilitate pathogen spread. In a color 

board experiment (yellow, green or white), it was observed that the yellow color board attracted more adult 

psyllids, indicating that psyllid adults preferred yellow color. Late stage psyllid nymphs (3rd to 5th instar) could 

make significant horizontal and vertical movements. In HLB-affected trees, nymphs were more attracted towards 

yellowing young shoots. Yet, movement was slower in HLB-affected trees than that in healthy trees. In healthy 

trees, number of nymphs moving downwards was significantly higher than that in HLB-affected trees. 

S16P10 

Effectivity of Huanglongbing vector (Diaphorina citri kuw.) control citrus grower group based in 

regency of Sambas, West Kalimantan, Indonesia 

Supriyanto A.S. 1 , Nurhadi N. 1 , Zuhran Z. 2 , and Purbiati P. 3 

1 Balai Penelitian Tanaman Jeruk dan Buah Subtropika (Balitjestro), Agriculture, Indonesia; 2 Balai Pengkajian Teknologi Pertanian 

Kalimantan Barat (BPTP Kalbar), Agriculture, Indonesia; and 3 Balai Pengkajian Teknologi Pertanian Jawa Timur (BPTP Jatim), Agriculture, 

Indonesia. arry_supriyanto@yahoo.com 

The purpose of this study was to determine the effectiveness of Huanglongbing vector control recommendation 

citrus grower group based. Studies have been carried out in 2010 in Tebas Sungai village, Sambas district, with 

11 tangerine groves owned by growers in the citrus grower association of Sambas district. The tangerine 

grove that been used are, one grower’s orchard as a demonstration plot in a particular citrus grower group 

(orchard I); five other citrus orchards with different ownership at the same citrus grower group (orchard II), 

as well as five other citrus orchard with different ownership which each of them spreads over five different 

citrus grower groups outside the farm demonstration plots (orchard III). The recommendation technology 

for controlling Huanglongbing vector which applied in this experiment, included bark painting by systemic 

insecticide of imidacloprid for two each 1.5-month and spray using contact insecticide with dimethoate to 

the plant crown which application time been alternated after bark painting application. The effectiveness of 

technology implementation is measured by a decrease psyllid populations found in citrus samples in adult 


stage, nymphs and eggs that were observed at regular intervals every two weeks during the flushing to the 

14th week after the first treatment. The results showed if the recommended treatment technology were 

absolutely proven to reduce Huanglongbing vector population in significant, namely in the orchard I, II, and III 

respectively at 95.3%, 84.7%, and 72% for stage imago; 97.3 %, 80%, and 100% for stage nymphs; and 98.5%, 

100% and 100% for the egg stage. 

S16P11 

Behavioural responses of Diaphorina citri to host plant volatiles. 

Fancelli M. 1 , Birkett M.A. 2 , Pickett J.A. 2 , Moraes M.C.B. 3 , Laumann R.A. 3 , and Borges M. 3 

1 Embrapa Cassava & Fruits (EMBRAPA/CNPMF), Laboratory of Entomology, Brazil; 2 Rothamsted Research (RRES), Biological Chemistry 

and Crop Protection, UK; and 3 Embrapa Genetic Resources & Biotechnology (EMBRAPA/CENARGEN), Laboratory of Semiochemicals, 

Brazil. fancelli@cnpmf.embrapa.br 

The Asian Citrus Psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae) is a vector of the greatest threat to the 

citrus production and industry in the world known as HLB (Huanglongbing = ex-greening). Differences in host 

plant suitability for insect development and disease incidence have been reported. Thus, D. citri responses to 

plant volatiles were investigated in order to identify attractants from host plants. Volatiles were collected from 

host plants, Citrus sinensis cv. Pera D6, C. reshni - Cleopatra, Citrus limettioides and Poncirus trifoliata. A four-arm 

(Pettersson) olfactometer was used to determine behavioural responses of D. citri females to the volatiles. One 

treated arm (plant volatiles) was compared against control arms (hexane). Air was drawn from the olfactometer 

at the rate of 200 ml/min. One adult female starved for 1 h was exposed to the volatiles for 16 min, and every 2 

min the position of the olfactometer was rotated by 90°. The time spent by D. citri in the different arms of the 

olfactometer was recorded using OLFA software. The data were analysed using a two-sample unequal variance 

t-test. D. citri spent more time (P< 0.01) in the arm treated with Citrus sinensis cv. Pera volatiles when compared 

to control arms, but no differences between treatments and controls were observed for the other plants. These 

data so far provide evidence for differences in susceptibility of potential host plants. 

S16P12 

Efficacy of selected insecticides for the control of the California Red Scale in Southern Italy. 

Campolo O., Grande S.B., Chiera E., and Palmeri V. 

University of Reggio Calabria (UNIRC), Department of Agricultural and Forest Systems Management, Italy. orlando.campolo@unirc.it 

The California Red Scale (CRS), Aonidiella aurantii (Maskell), is considered one of the most important pests of 

citrus in the Mediterranean basin as well as in other citrus growing areas worldwide. In Southern Italy, citrus 

is the most widely cultivated crop and the control of the CRS relies mainly on the application of synthetic 

insecticides. During 2009 and 2010, selected insecticides (spirotetramat, chlorpyriphos and pyriproxyfen) were 

evaluated against this pest in two Calabrian citrus orchards under integrated pest management. Treatments 

were performed according to the dosage reported on the label of the commercial products. Two treatments, at 

15-day interval, were performed. Control plots were sprayed with water only. Efficacy was assessed 7, 14, 21, 

and 28 days after the first treatment and at the harvest. In both trials, spirotetramat showed the highest levels of 

efficacy against CRS and other citrus pests (citrus leafminer, aphids and mites) that were adequately controlled 

until the harvest. At harvest, spirotetramat also had the best visual acceptance by a panel of consumers. 

S16P13 

Altea (Eastern Spain) area-wide project to control California Red Scale Aonidiella aurantii 

(Hemiptera: Diaspididae) based on conservation and release biological control agents. 

Laborda R. 1 , Garcia-Mari F. 2 , Sanchez A. 1 , Xamani P. 1 , Garcia A. 3 , Punset C. 4 , Bernabeu P. 5 , Aznar M. 5 , and Bertomeu S. 1 

1 Universitat Politécnica de Valencia (UPV), Ecosistema Agroforestales, Spàin; 2 Universitat Politécnica de València (UPV), Instituto 

Agroforestal Mediterráneo, Spain; 3 Universitat Politècnica de València (UPV), Hidráulica, Spain; 4 Ayuntamiento de Altea, Spain; and 

5 Cooperativa Agrícola de Altea, Spain. rlaborda@eaf.upv.es 

The municipality of Altea includes a large rural area in which citrus orchards and country cottages coexist. A 

municipal initiative instituted to reduce the risk of pesticides used to control the principal pest of citrus crops 


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in the area, the California Red Scale (CRS) Aonidiella aurantii (Maskell). A surface area of 66 ha surrounding the 

main urban area was selected for study in 2010. The alternative to the use of synthetic organic pesticides was 

the mass release of biological control agents (Aphytis melinus DeBach (Aphelinidae), Rhyzobius lophanthae 

(Blaisdell)(Coccinellidae) and Comperiella bifasciata (Howard) (Encyrtidae) and the application of essential oil 

(Orizone®) when population of CRS reached a threshold of 2% infested fruits. Additionally, a cover crop was 

mechanically managed in a 30 ha surface area and -beneficial fauna identified. The results showed that the 

intervention threshold was not reached in 93% of the surface area due to the biological control exerted by the 

parasitoid releases as well as by the activity of naturally occurring populations of beneficial insects. 

In 2011 we analyzed the real effect of mass releases of A. melinus, considering the high levels of native fauna 

observed in the previous year. Different release rates, ranging from 0 to 100,000 A. melinus/ha, were compared. 

No differences were observed between orchards with or without releases, nor among different levels of release. 

These results confirm the importance of conservation biological control strategies in CRS management. 

S16P14 

Hyperparasitism may prevent efficient regulation of Aphis spiraecola Patch. (Homoptera: 

Aphididae) in citrus orchards by primary parasitoids. 

Gómez-Marco F. 1 , Tena A. 1 , Jacas J.A. 2 , and Urbaneja A. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Unidad Asociada de Entomología UJI-IVIA; Departamento de Entomología, 

Spain; and 2 Universitat Jaume I (UJI), Unitat Associada d’Entomologia IVIA-UJI, Spain. fmgomez@ivia.es 

Aphis spiraecola Patch., is a key pest of clementine mandarins in Spain. The biological control of this species 

is far from satisfactory and we have tried to unravel the reasons for this failure. We sampled mummies of A. 

spiraecola during the spring population that this species exhibits in Valencia and kept them until emergence 

of the developing parasitic wasp. At least two plausible explanations for deficient biological control have 

been found. On the one hand, very few parasitoid species (n=440) could complete their development in this 

aphid. Parasitic wasps belonging to the genus Trioxys were the only specimens successfully reared out of 

these mummies. Percent parasitism by these wasps accounted for 14 % of total mummies caught. On the 

other, hyperparasitism was extremely high (67%) and Syrphophagus aphidivorus, a primary hyperparasitoid, 

alone represented more than 55% of all hyperparasitoids found. Molecular tools could probably help to shed 

light into the complicated trophic relationships established among A. spiraecola parasitic guild. Disentangling 

these relationships will probably pave the way for improving the biological control of this species. 

S16P15 

Citrus mealybug biological control strategies and large scale implementation on citrus in Turkey. 

Erkilic L.B., Demirbas H., and Guven B. 

Biological Agriculture Consulting and Engineering Co (BIYOTAR), Biological Control, Turkey. lerzane@superonline.com 

Citrus Mealybug, Planococcus citri (Risso) (Hem.: Pseudococcidae) is one of the main pests on citrus in Turkey. 

Since 1970 biological control implementation in citrus orchards continue on Citrus mealybug with Cryptolaemus 

montrouzieri Mulsant (Col.:Coccinellidae) and Leptomastix dactylopii Howard (Hym.:Encyrtidae). The interests 

in biological control tend to be increase due to human and environmental health, food safety and pesticide 

residue issues. The application dosages of C. montrouzieri and L. dactylopii range between 10 to 20 individuals 

per tree according to the mealybug population level and also the citrus variety. The main strategy is to use 

both beneficials C. montrouzieri and L. dactylopii at the early stage of mealybug population. L. dactylopii 

can be released at the beginning of mealybug population build up, before mealybug egg production, and C. 

montrouzieri should be released when the mealybug population is producing eggs. If the mealybug population 

has both, adults and egg masses, then both beneficials should be released together. In large scale application 

the early usage sometimes is not possible, because other main pests such as the California Red Scale and 

Rust mite are present and chemical applications may take place at the beginning of season. In this case a 

compatible pesticide use is preferred to carry out the biological control releases. 

In Turkey due to food safety reasons and also Min. of Agriculture subvention given for the usage of biological 

control agents would be increase the application area in coming future. 


S16P16 

Repellency and acceptability of several substances by ant species in citrus groves in Spain. 

Campos Rivela J.M., Martínez-Ferrer M.T., Fibla J.M., and Pla M. 

IRTA - Amposta, Sustainable Plant Protection - Entomology, Spain. jmiguel.campos@irta.cat 

Ants are associated with outbreaks of insects principally because of their interference with the biological control 

of these pests. The control of ant populations should be considered as a key component in the development 

of strategies for pest management. Ants communicate between individuals by using semiochemicals 

for several purposes. Then again, the success of chemical control of ants is based, among others, on the 

acceptability of the ant worker to bring the toxic to the colony, and especially to the queen. Field bioassays 

were performed on Lasius grandis, Pheidole palidulla and Linepithema humile. Bioassay arenas were located 

under citrus trees, where the selected species was actively foraging before. Only one species was allowed 

to forage in each experiment. One of the bioassay was carried out to quantitatively determine the repellent 

activity of semiochemicals farnesol and methyl eugenol against these species. Circular barriers of beeswax 

containing different concentration of the semiochemicals (0.03%, 0.06%, 0.12%, 0.24%, 0.48%, 0.96%, 2%, 

3% and 5%) were used. The number of ants crossing these barriers during 2 minutes in four samples each was 

recorded. A non-choice test field bioassay was conducted to qualitatively determine the acceptability of some 

toxicants formulated in 25% sucrose. Toxicants used were: pyriproxyfen, boric acid, spinosad, imidacloprid, 

and abamectin. The obtained results are presented and discussed. 

S16P17 

Taxonomic studies for classical biological control of Delottococcus aberiae (Hemiptera: 

Pseudococcidae). 

Beltrà A. 1 , Navarro-Campos C. 1 , Garcia-Marí F. 1 , Malausa T. 2 , Giliomee J.H. 3 , Addison P. 4 , and Soto A. 1 

1 Universitat Politècnica de València (UPV), Instituto Agroforestal Mediterráneo, Spain; 2 Institut National de la Recherche Agronomique 

(INRA), Biologie des Populations Introduites, France; 3 University of Stellenbosch (US), Department of Botany and Zoology, South 

Africa; and 4 University of Stellenbosch (US), Department of Conservation Ecology and Entomology, South Africa. albeliv@etsia.upv.es 

Delottococcus aberiae Brain (Hemiptera: Pseudococcidae) is a mealybug of Afrotropical origin that has been 

recently introduced in eastern Spain. The absence of efficient natural enemies has led to population outbreaks 

in some citrus orchards reducing fruit quality and production. This species was described as a minor pest of 

citrus in South Africa and shows small morphological differences with the Spanish strain. Mealybugs are 

typical invasive pests and classical biological control programs have been traditionally applied against them. 

However, the misidentification of the mealybug species and their natural enemies has led to the failure of 

some parasitoid introductions. In this work we carried out a survey of Delottococcus mealybugs and their 

parasitoids in different orchards and natural ecosystems in South Africa as a first step towards a classical 

biological control program. We provide a multi-criterion characterization of mealybugs and parasitoids 

combining morphological and genetic techniques. DNA was amplified from five different loci in mealybugs 

and four loci in parasitoids. Genetic analysis revealed significant differences among Spanish and South 

African mealybug populations. Moreover, new parasitoid species were recorded and their DNA sequences 

are provided. The potential use of these parasitoids in biological control of D. aberiae in Eastern Spain is 

discussed. 

S16P18 

Canibalism and intraguild predation in citrus mealybug natural enemies. 

Gkounti V.T. 1 , Savvopoulou-Soultani M. 1 , Kontodimas D.C. 2 , and Milonas P.G. 2 

1 Aristotle University Thessaloniki (AUTH), Phytopathology, Greece; and 2 Benaki Phytopathological Institute (BPI), Entomology and 

Agricultural Zoology, Greece. vgkounti@agro.auth.gr 

Cannibalism and interspecific interactions among insect natural enemies are common, yet these behaviors 

are frequently omitted from predatory-prey theory and empirical studies. These interactions may disrupt, 

facilitate or augment biological pest control.- In the present study intra- and interspecific interactions 


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among three natural enemies of the citrus mealybug Planococcus citri (Hemiptera: Pseudococcidae) were 

empirically investigated. The natural enemies’ guild consisted of the predatory coccinellids Nephus includens 

and Cryptolaemus montrouzieri and the endoparasitoid Anagyrus pseudococci. Cannibalism and intraguild 

predation between the two predators have been studied in presence and absence of prey. It has been 

showed that N. includens adults readily consume conspecific eggs despite the availability of prey. However, 

as prey availability increases their tendency to cannibalism decreases. They also consume C. montrouzieri 

eggs in the absence of prey, while avoid them when alternative prey is offered. C.montrouzieri preys on 

eggs of N. includens, regardless of prey presence. We also investigated predation risks for immature stages 

of A. pseudococci by N. includens adults. Our results showed that larvae of A. pseudococci face increased 

intraguild predation at early developmental stages, before mummification of the host. After mummification 

N. includens does not prey upon it. The strength of these interactions is discussed in relation to sustainable 

biological control. 

S16P19 

Biological control of the citrus mealybug: dispersion pattern of the parasitoid Anagyrus sp. Near 

pseudococci, during augmentative releases. 

Franco J.C. 1 , Zina V. 1 , Silva E.B. 1 , Steinberg S. 2 , Belda J.E. 3 , Branco M. 1 , Suma P. 4 , and Mendel Z. 5 

1 Instituto Superior de Agronomia, Universidade Técnica de Lisboa (ISA/UTL), Centro de Estudos Florestais, Portugal; 2 BioBee Sde 

Eliyahu Ltd. (BioBee), Research & Development, Israel; 3 Koppert Espana SL (Koppert), R&D Dept, Spain; 4 Università degli Studi di 

Catania (DGSAA/UniCT), Dipartimento di Gestione dei Sistemi Agroalimentari e Ambientali - Sez. Entomologia Agraria, Italy; and 

5 Agriculture Research Organization, Volcani Center (ARO), Dep. Entomology, Israel. verazina@isa.utl.pt 

Anagyrus sp. near pseudococci (Hym.: Encyrtidae) is the major parasitoid of the Citrus Mealybug (CM), 

Planococcus citri and the Vine Mealybug (VM), Planococcus ficus (Hemip.: Pseudococcidae). The wasp is 

commercially available to be used in augmentative releases to control both mealybug species. The effectiveness 

of this biological control tactic is dependent, among other factors, on the release rate and distribution pattern 

of the wasps within the target area. Therefore, knowledge on the dispersion of the parasitoid is of importance 

to optimize the protocols of the augmentative release. Recently, we showed that the sex pheromone of the 

VM attracts females of A. sp. near pseudococci and increases parasitization levels of CM by the wasp. In the 

present study, we employed VM pheromone baits to study the spatial and temporal dispersion pattern of A. 

sp. near pseudococci in augmentative releases. The experiment was set up in a 5 ha maritime pine stand, ca. 

20 Km south of Lisbon. The absence of a local population of the parasitoid was verified by activation of traps 

baited with VM pheromone before the release. Sticky plate traps baited with 50 µg of VM pheromone were 

suspended up to 100 m away from the wasp release point along six different transects and six distances (10, 

20, 40, 60, 80 and 100 m), in a circular layout. At the release point, we installed 18 commercial containers 

of A. sp. near pseudococci (CITRIPAR), each with 500 mummies. Daily monitoring of wasp captures showed 

that the parasitoid was able to disperse up to 100 m within first two days after release. The mean number of 

wasps captured within six days in pheromone traps decreased exponentially in function of distance from the 

release point. Mean captures at 100 m-correspond to-ca. 11% of-those at 10 m. Our results suggest that 3-4 

release points per hectare are sufficient for a good cover of a target area by the parasitoid in augmentative 

release schemes. 

S16P20 

Study on biological control and trap techniques of Thrips flavidulus (Thysanoptera: Thripidae) in 

citrus orchards 

Yao H., Yu F., and Zhang H. 

Huazhong Agricultural University (HZAU), College of Plant Science and Technology, China. hongyu.zhang@mail.hzau.edu.cn 

Thrips flavidulus has caused great damages to citrus orchards in China. In this study, the functional and 

numerical responses for the adults of the predatory mites Neoseiulus cucumeris, Neoseiulus barkeri and 

Euseius nicholsi on T. flavidulus first-instar larvae were studied to evaluate their predation ability on T. 

flavidulus. The results showed that the functional response of adult N. cucumeris, N. barkeri and E. nicholsi 


could be described by the Holling II functional response type. The results suggested that predation ability of N. 

cucumeris was strongest to T. flavidulus among three predatory mites and prey density significantly influence 

reproductive ability of N. cucumeris and E. nicholsi, but not N. barkeri. Among 10 types of colors sticky cards 

i.e., yellow, blue, deep-blue, white, red, green, purple, gray and pink in citrus orchards, T. flavidulus had the 

strongest preference to the blue and deep blue sticky cards. The thrip numbers on those cards were significant 

different from those on the other eight colors sticky cards. The trapping techniques of blue sticky cards were 

discussed. Effect of 16 different plant volatile compounds on the behavior of adult female T. flavidulus thrips 

was tested with a Y-tube olfactometer. The results showed that T. flavidulus were attracted by the compound 

of benzenoids and monoterpenes isoprenoids. The compound A and E have the significant attraction to thrips 

at concentration 10% and 1%. 

This work is supported by the earmarked fund for Modern Agro-industry Technology Research System of 

China (No. CARS-27), and Special Fund for Agro-scientific Research in the Public Interest (no. 200903032). 

S16P21 

Thysanoptera occurring in clementine mandarin under three ground cover management 

strategies: species composition, abundance and distribution. 

Aguilar-Fenollosa E., and Jacas J.A. 

Universitat Jaume I (UJI), Ciències Agràries i del Medi Natural, Spain. aguilare@uji.es 

There is a complex of Thysanoptera species inhabiting citrus and some of them are considered pests. 

This study was aimed at studying the effect of ground cover management on thrips species composition, 

abundance and distribution in commercial clementine mandarin orchards. Three ground cover management 

systems were compared: resident vegetation cover, Festuca arundinacea Schreber (Poales: Poaceae) cover, 

and bare soil. The ground cover influenced the abundance of some thrips species in the cover. Among 

the main species causing fruit damage in citrus, we found Frankliniella occidentalis (Pergande) and Thrips 

tabaci Lindeman. The F. arundinacea cover strongly depressed the abundance of these thrips species in 

ground cover vegetation. The resident vegetation cover could provide a range of suitable hosts supporting 

populations of potential thrips pest species out of the main citrus peak blooming period. Apart from that, 

the F. arundinacea cover, which hosted Poaceae-specific thrips species, could provide alternative food 

enhancing populations of predatory phytoseiid mites which could reduce populations of potential citrus 

pests below economic injury level. Our results confirm the suitability of F. arundinacea as a cover crop for 

clementine mandarins. 

S16P22 

Effect of biotic and abiotic factors on the insurgence of fruit scars in Italian orange orchards. 

Siscaro G. 1 , Zappalà L. 1 , Biondi A. 1 , Conti F. 2 , and Fisicaro R. 2 

1 University of Catania (DiGeSA), Department of Agri-food and Environmental Systems Management, Italy; and 2 Sicilian Region - 

Assessorship of Agricultural and Food Resources (SFR - OMP), Regional Plant Health Service, Italy. fconti@regione.sicilia.it 

Citrus fruit rind scars are corky tissue formations, the structure, shape and distribution of which may be very 

variable on the fruit surface. Such phenomena have been increasingly recorded during the last few years 

on lemon and orange fruits, as confirmed by surveys carried out in several Italian packing houses. They are 

referred to fruit scars induced by various biotic factors such as thrips feeding and physical damage, mainly 

caused by brunch rubbing due to wind or spraying equipments. In 2011, a field survey was conducted in a 

Sicilian organic orange orchard, to evaluate possible correlation between thrips infestation, brunch rubbing 

and fruit scars. Two plots were evaluated; one planted with the variety Navelina and the other with Tarocco 

Scirè. No insecticides were applied during the observation period. Thrips infestation was monitored weekly 

from the flowering to fruit-set, and type, incidence and severity of fruit scars were assessed by field direct 

observations at fruit-set and harvest. In addition, a survey was carried out in 7 packing houses located in 

the same production area to assess the rate of downgrading due to fruit scars. Although very few flowers 

and young fruits were found infested by thrips (mainly Pezothrips kellyanus and Frankliniella occidentalis), 


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a high incidence of damaged fruits (up to 40%) was observed in both varieties, with scars apparently due to 

mechanical damage. The same trend, both in terms of type and incidence, was observed during the packing 

houses survey with an average of 35% of scared fruits (min 20-max 50%). The results showed that few scars 

are attributable to thrips infestation, while physical factors, notably wind and spraying equipment, play the 

key role. This finding also stresses the urgent need to carefully discriminate the origin of fruit scars in order to 

avoid unnecessary insecticide applications in citrus. 

S16P23 

Thrips population dynamics, composition and first survey of ground-dwelling predatory mites in 

lemon orchards in Italy. 

Biondi A. 1 , Zappalà L. 1 , Tropea Garzia G. 1 , Perrotta G. 2 , and Siscaro G. 1 

1University of Catania (UNICT), Department of Agri-food and Environmental Systems Management, Italy; and 2Assessorato regionale 

delle Risorse agricole e alimentari, Regione Siciliana (U.P.A.), Dipartimento Regionale Azienda Foreste Demaniali, Italy. 

antonio.biondi@unict.it 

Several thrips species are known to infest citrus orchards worldwide. Flowers are usually preferential feeding 

sites, but developing fruits are also attacked. Pezothrips kellyanus has emerged as a key thrips pest on citrus 

in Italy, and knowledge on its biology and natural enemies are still largely insufficient. We conducted a survey 

in two Sicilian lemon orchards, aimed at assessing the thrips species composition and population dynamics 

on lemon flowers, young fruits and weed flowers. Thrips ecology was also studied placing double-sided sticky 

traps under the tree canopy. Ground-dwelling predatory mites were collected in the soil samples from below 

the canopy using a Berlese apparatus. Kelly’s thrips was the most abundant species (88.6-91.2%) infesting 

lemon and its presence was well correlated to blooming. On the 23 weed species sampled, the commonest 

thrips were Frankliniella occidentalis and Megalurothrip ssp., while P. kellyanus was observed only on 6 

species, mainly Asteracee. The data obtained confirmed a significant soil phase of the pest, since in the up 

and bottom trap sides there were two peaks of nymphs and adults, respectively. Of sampled mites, 20% were 

predaceous Laelapidae, Macrochelidae and Phytoseiidae. This study is the first step towards establishing a 

scientific basis for an effective soil and weed management system aimed at reducing thrips infestation in 

Italian lemon orchards. 

S16P24 

Pollen availability in the cover crop may affect the biological control of Tetranychus urticae in 

citrus. 

Pina T. 1 , Argolo P.S. 2 , Urbaneja A. 2 , and Jacas J.A. 1 

1Universitat Jaume I (UJI); Unitat Associada d’Entomologia UJI-IVIA, Departament de Ciències Agràries i del Medi Natural, Spain; and 

2Instituto Valenciano de Investigaciones Agrarias (IVIA); Unidad Asociada de Entomología UJI-IVIA, Departamento de Entomología, 

Spain. pina@uji.es 

Tetranychus urticae Koch (Acari: Tetranychidae) populations in citrus can be regulated through the management 

of the cover crop. A mono-specific cover of the grass Festuca arundinacea Schreber (Poaceae) enhanced the 

diversity and abundance of Phytoseiidae mites compared with a multifloral cover. This increase resulted in a 

better control of T. urticae. Pollen availability and quality could be behind this result. Whereas multifloral cover 

offers a long-term source of a wide variety of pollen, F. arundinacea offers one single type of pollen in spring 

only. As a consequence, the generalist pollen feeder Euseius stipulatus (Athias-Henriot), which exerts direct 

and indirect negative effects on specific predators as Neoseiulus californicus (McGregor), is highly favored in 

multifloral covers. To determine the role of pollen quality on the biological control of T. urticae by phytoseiid 

mites, the effect of two types of pollen on the efficacy of E. stipulatus and N. californicus to regulate T. urticae 

populations was studied under semi-field conditions. Results suggest that pollen provision does not enhance 

the ability of these phytoseiids to control T. urticae. However, pollen quality directly affected the numbers 

of E. stipulatus. Therefore, poor quality pollen may prevent pollen feeders from reaching high numbers and 

indirectly benefit T. urticae control by specialist phytoseiids. 


S16P25 

Assessment of trophic interactions among citrus mites by DNA-based gut content analysis. 

Pérez-Sayas C., Pina T., Gómez-Martínez M.A., Jacas J.A., and Hurtado M.A. 

Universitat Jaume I de Castelló (UJI), Ciencias Agrarias y del Medio Natural, Spain. mhurtado@uji.es 

Tetranychus urticae Koch and Panonychus citri (McGregor) (Acari: Tetranychidae) are the most important 

tetranychid mites affecting citrus orchards in the Region of Valencia (Eastern Spain). Their main natural 

enemies are different phytoseiid mites. These predators can prey on both tetranychid mite species but their 

actual effect in the field remains unknown. The analysis of the phytoseiid’s gut content using molecular 

techniques can provide a new tool to quantify predation. These techniques can reveal the real prey spectrum 

of a polyphagous predator, and the range of predators feeding on a particular species. Squash-capture and 

tissue-print of field-collected phytoseiid mites followed by Multiplex PCR has revealed to be a valid alternative 

to classic taxonomy for mite identification. Furthermore, it has allowed establishing prey preferences and 

mite trophic interactions under real field conditions. In the citrus agroecosystem, the specialist Phytoseiulus 

persimilis Athias-Henriot clearly prefers T. urticae even when this prey is scarce, whereas the generalist 

pollen-feeder Euseius stipulatus (Athias-Henriot) behaves as an omnivorous species that does not seem to 

prey preferentially on T. urticae even when this species is highly abundant. 

S16P26 

Effectiveness and economics of a novel proactive approach for managing the Citrus Rust Mite in 

Texas. 

Setamou M., and Sekula D. 

Texas A&M University-Kingsville Citrus Center (TAMUK-CC), Agriculture, Agribusiness and Environmental Sciences, USA. 

mamoudou.setamou@tamuk.edu 

The Citrus Rust Mite (CRM), Phyllocoptruta oleivora (Ashmead) (Acari: Eriophyidae), is considered the most 

economically important pest affecting citrus production in Texas citrus because the majority of citrus produced 

is destined for fresh fruit market. Feeding damage of the pest causes conspicuous injury to fruit leading to 

blemish and discoloration of the rind. In light of the absence of any effective alternative CRM control method, 

the use of chemical miticides is the only management strategy used by growers. Traditionally, growers scout 

for mite population on fruit and once a certain population level is reached starting from April-May, they 

decide to begin spraying. This traditional approach provides temporary control of CRM in citrus orchards. 

Since CRM also reproduces on leaves and citrus trees have evergreen vegetation, effective control will require 

targeting CRM when its populations are at their lowest during the dormant period. Thus, pre-bloom proactive 

spray initiation dates were compared to the traditional post-bloom date. Significant and long term reduction 

of CRM densities were observed with the proactive spray programs. The gross returns were 1.1 to 1.3-fold 

higher with the proactive spray. This novel approach also preserves predatory mite populations which would 

provide additional control to various mites. Although this novel approach did not reduce chemical input and 

associated costs of control, the better CRM control achieved made its adoption an effective alternative both 

ecologically and economically. 

S16P27 

Spider mite response in citrus rootstocks is mediated by the oxylipin pathway. 

Agut B. 1 , Hurtado M.A. 1 , Jacas J.A. 1 , and Flors V. 2 

1 Universitat Jaume I (UJI), Unitat Associada d’Entomologia IVIA-UJI, Spain; and 2 Universitat Jaume I (UJI), Metabolic Integration and 

Cell Signaling Group, Spain. bagut@uji.es 

Citrus rootstock selection has been traditionally based on their resistance to pathogens and tolerance to 

abiotic stresses. However, the resistance to arthropod pests has been consistently neglected. Recently, 

it has been shown that citrus rootstocks can influence the life history of the phytophagous spider mite 

Tetranychus urticae Koch (Acari: Tetranychidae). To compare the usefulness of pathogen resistance-based 

rootstock selection with arthropod tolerance/resistance, we have performed comparative experiments of 


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spider mite performance on citrange Carrizo (Citrus tristeza virus, CTV, tolerant), Cleopatra mandarin (CTV 

and salt tolerant) and Sour orange (CTV sensitive and limestone tolerant). Sour orange showed reduced 

leaf damage symptoms and supported lower mite populations. Taking together the genetic analysis of 

defense pathways and the phenotype, results suggest a relevant role of the oxylipin pathway in the 

plant defense against T. urticae. Nevertheless the SA-related responses cannot be neglected, since the 

most resistant rootstock, Sour orange, still displayed enhanced levels of this hormone and PR5 marker 

gene expression upon spider mite infestation. Because the LOX inhibitor Phenidone totally abolished the 

enhanced response of Sour orange, oxylipins are probably essential signals controlling citrus defense 

responses against arthropod infestations. 

S16P28 

Impact of three ant species on pest populations in Mediterranean citrus orchards. 

Calabuig A. 1 , Pekas A. 2 , and García Marí F. 1 

1Instituto Agroforestal Mediterráneo (IAM), Entomología, Spain; and 2Biobest Belgium NV (Biobest), R&D, Belgium. 

alteakova@hotmail.com 

We studied the influence of three ant species, the native to the Mediterranean Pheidole pallidula (Nylander) 

and Lasius grandis (Forel) and the invasive Linepithema humile (Mayr), on the population densities of 

three citrus pests: the honeydew producer woolly whitefly Aleurothrixus floccosus (Maskell) and the 

non-honeydew producers, California Red Scale (CRS) Aonidiella aurantii (Maskell) and Citrus leafminer 

Phyllocnistis citrella (Stainton). From April to November 2011 we monitored ant activity, CRS densities 

on fruits and twigs as well as whitefly and citrus leafminer population densities in ant-allowed and antexcluded 

trees in three citrus orchards each one dominated by one ant species. The most active ant species 

was L. humile (average for the observation period 64.5 ants/minute climbing up or down the tree trunk) 

followed by P. pallidula (4.5 ants/minute) and L. grandis (2.2 ants/minute). On fruits, A. aurantii densities 

in the ant-excluded trees were on average 31% lower for the three ant species studied than in the antallowed 

trees.- On twigs no differences in A. aurantii densities were detected between treatments. In the 

case of A. floccosus results varied depending on the ant species; in the presence of L. humile, whitefly 

population densities increased by 66%. Likewise, for P. citrella we found significant differences in densities 

between treatments only for L. humile (increase of 15% when ants were present). These results show that 

ant activity may have an effect on the abundance of honeydew and non-honeydew producing pests, yet 

this effect depends on the ant species involved. 

S16P29 

Ant nests distribution in citrus groves under different ground cover management strategies in 

Spain. 

Martinez-Ferrer M.T., Campos Rivela J.M., Fibla J.M., and Pla M. 

Institut de Recerca i Tecnologia Agroalimetàries (IRTA), Sustainable Plant Protection Entomology, Spain. teresa.martinez@irta.cat 

Ants represent a large proportion of the arthropods present in citrus ecosystem. Their activity may have a 

striking impact on the abundance of the rest of the arthropods, pests and natural enemies. The structure 

of ant communities may change as a result of changes in habitat, differences in growth or in the physical 

structure. Ground cover management can modify the inter-specific competition between ant species. The 

ant nests spatial distribution, diversity and abundance were studied in eight citrus groves in northeastern 

Spain (Tarragona) under different ground cover management: a) resident wild cover, b) sown cover of Festuca 

arundinacea and Poa annua, and c) bare soil. The area covered by 60 trees -ten trees per six contiguous 

rows- and the corresponding transects among the rows was monitored in spring, summer and autumn. The 

number of active nests of each species and the position of the nests were recorded. Ant nests distribution was 

obtained by the distance to the nearest neighbor method. The intra-annual nest permanence and the nest 

renovation indexes were determined for the most abundant ant species. The results obtained are presented 

and discussed. 


S16P30 

Composition and flight activity of Staphylinidae (Coleoptera) in citrus orchards 

Adorno A. 1 , Biondi A. 2 , Zappalà L. 2 , Siscaro G. 2 , and Sabella G. 1 

1 University of Catania (UNICT), Department of Biological, Geological and Environmental Sciences, section of Animal Biology “M. La 

Greca”, Italy; and 2 University of Catania (UNICT), Department of Agri-food and Environmental Systems Management, Italy. 

antonio.biondi@unict.it 

Staphylinid beetles are among the most important epigeic polyphagous arthropods living in various agroecosystems 

and represent an important component of functional biodiversity. Their flight activity in citrus 

orchards is still poorly investigated and, since most of them are insect predators, many species may play 

important roles in pest control. The aim of this study was to gain knowledge of the flying staphylinid fauna and 

its temporal distribution in citrus orchards. A survey was carried out, from December 2009 to August 2011, 

in a 70ha citrus farm located in the typical orange production area of Sicily. Two types of flight interception 

trap techniques were used: (i) 12 window traps maintained over one year and the trap content was serviced 

fortnightly, and (ii) 21 samplings carried using a net-car trap. The sampled Staphylinidae belong to 150 

species, with 30 representing more than 90% of the whole sampled material. The most abundant, presented 

in decreasing order of collected number of specimens, were: Megarthrus bellevoyei, Anotylus nitidulus, 

Gabronthus maritimus, Paraphloeostiba gayndahensis, Scopaeus debilis, A. speculifrons, Cordalia obscura, 

Amarochara umbrosa, Proteinus atomarius, Carpelimus corticinus, Philonthus concinnus, Heterothops 

minutus, S. mitratus, Tachyporus nitidulus, Aloconota gregaria, Atheta palustris. Peak of flight activity for 

most species was typically in spring or spring-autumn, while species with strictly summer and winter peaks 

were a minority. Only some of the sampled species have been reported as potential biocontrol agents of 

citrus pests and further investigation is needed to assess the ecological services that they can provide in an 

integrated pest management framework. The results proved that several predatory staphylinid species do 

fly actively within a citrus orchard, suggesting the importance of increased knowledge on the dynamics of 

movement from neighboring ecological infrastructures to citrus cultivations. 

S16P31 

Entomo-pathogenic nematodes to combat -infestations at ticofrut 

Camacho H. 1 , Yglesias G. 2 , and Faerron P. 2 

1Tico Frut Company. University of Costa Rica - Fabio Baudrit Agricultural Research Station, Costa Rica; and 2TicoFrut, Agricultural 

Department, Costa Rica. hcamachov@hotmail.com 

Tico Frut´s 15,000 hectares of orange groves in Costa Rica undergo frequent infestations of Phyllophaga 

spp. beetle larvae (Coleoptera: Scarabedidae) and Nasutitermes spp. termites (Ispotera: Termitidae) both 

of which cause major losses. In order to eliminate these pests by means of environmentally low-impact 

strategies, a program was implemented to apply the nematode Heterorhabdites bacteriophora (Nematoda: 

Heterorhabditidae). The nematodes are raised en masse in the larvae of Galleria mellonella. Each moth 

produces an average of 517 eggs during its life cycle, and lays them on wax paper in jars. 0.5 grams of eggs 

(approximately 1,100 ova) are placed on 100 grams of artificial food, where eclosion then occurs. Once they 

hatch, the larvae develop on a simple diet, with a density of 11 larvae per gram of food, during 15 days. 50% 

of the larvae survive. To complete their growth, the larvae are put into larger containers holding with 14,000 

larvae apiece for 15 days. The Galleria larvae are then parasitized by the nematodes in containers: in each one 

200 Galleria larvae are placed along with 100 infectious nematode. After thirteen days, the infectious juveniles 

are collected in white traps. For this year´s planting of 500,000 orange tree seedlings, 1000 nematodes were 

put into five liters of water per tree; this approach was needed due to the fact that the replanting had to be 

carried out during the period prior to the start of the rainy season, when the soil was very dry. In order to 

apply the nematodes to the termite mounds, an opening was made in the middle section of each one, and it 

was then sprayed with the nematode-water solution with a backpack pump unit. Both the beetle larvae and 

the termites were infected with the bacteria transmitted by the nematodes, and they died within a 24 to 28 

hour period. This control method does not pollute the environment; it works quickly without damaging water 

sources or harming humans, and is highly effective. 


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S16P32 

Monitoring and Management of Naupactus (= Asynonychus) cervinus in citrus orchards in Chile. 

Luppichini P., and Olivares N. 

Instituto de Investigaciones Agropecuarias (INIA), CRI, La Cruz, Chile. pluppich@inia.cl 

Naupactus cervinus (Boheman) (Coleoptera: Curculionidae) is a pest rarely treated in Chilean citrus orchards. 

However, the detection of several egg masses under orange and lemon fruit calix has been reported as a 

refusal cause of the exported Chilean fruit. In order to improve-N.-cervinus control and to reduce its incidence 

in Citrus orchards, this study raises the hypothesis that an optimal pest management requires the design of an 

integrated monitoring system. Integrated pest management (IPM) assays were conducted in citrus orchards 

(orange and lemon) within the Valparaíso Region. Commercial N. cervinus pesticides and a toxic barrier were 

used as treatments. Prior to the application of the treatments, N. cervinus adult stage presence was monitored 

in tree canopies by shaking the branches and collecting the fallen insects in a plastic sheet placed underneath 

the trees. The pesticides (azinphosmetil, indoxacarb and methidathion) were applied to the tree’s canopy at 

manufacturer’s recommended dose. The toxic barrier (a.i. azinphosmetil) was physically placed around the 

trunk of the trees. Adults were collected from tree leaves every 15 days, 90 days after the application of the 

treatments, for evaluation. Foliar applications of azinphosmetil and indoxacarb display an effective control 

in orange and lemon orchards. However, the toxic barrier showed superior control performance compared 

to the sprayed pesticide treatments. Therefore, we conclude that the toxic barrier is an alternative for N. 

cervinus control in IPM. 

S16P33 

Population dynamics of citrus blackfly in Tahiti lime in the state of São Paulo, Brazil. 

Felippe N. 1 , and Raga A. 2 

1Pontificia Universidade Católica de Campinas, Brazil; and 2Instituto Biológico, Brazil. adalton@biologico.sp.gov.br 

Field investigations on the seasonal population dynamics of the Citrus Blackfly (CBF) Aleurocanthus 

woglumi Ashby (Hemiptera: Aleyrodidae) in Tahiti lime (Citrus latifolia) orchard were conducted at 

Artur Nogueira municipality, São Paulo State, Brazil, from August 2011 to June 2012. Twenty leaves per 

mature tree were collected at fortnightly intervals from ten previously marked trees. Under stereoscopic 

microscope we evaluated the spiralling oviposition and nymphal population. CBF showed the highest peak 

of oviposition during August 2011, reaching 52.9 eggs/leaf. From overall collections we obtained 23.0 eggs/ 

oviposition, ranging from a minimum of 7 eggs and a maximum of 53 eggs/oviposition. Approximately 

92% of the ovipositional masses had between 12 and 39 eggs. CBF egg-laying is confined to the lower 

leaf surface (abaxial). The highest nymphal population occurred during early April 2012, with average of 

13.0 nymphs/leaf. CBF immature population declined during the wetter season (October to March). The 

entomopathogenic fungus Aschersonia aleyrodis and Aegerita webberi occurred all year long and during 

the rainy season. 

S16P34 

Integrated strategies to monitor and control Citrus Flower Moth, Prays citri Mill. (Lepidoptera: 

Yponomeutidae) on nursery trees of the Mediterranean area 

Conti F., and Fisicaro R. 

Sicilian Region. Assessorship of Agricultural and Food Resources (SFR - OMP), Regional Plant Health Service, Italy. 

fconti@regione.sicilia.it 

Prays citri Mill. (Lepidoptera: Yponomeutidae), the Citrus Flower Moth (CFM), is regarded as a key pest of 

nursery trees in Sicily. Larvae damage flowers and new shoots. Furthermore, young larvae can penetrate 

small fruits. Growers may spray several times per year mainly with organophosphate insecticides. During the 

last 5 years, a new IPM approach has been evaluated. Different pesticides were assayed and the possibility 

to predict infestation by means of monitoring male flights with pheromone traps was assessed. In 2007, 


2010 and 2011, the efficacy of spray applications of fosmet, flufenoxuron and Bacillus thuringiensis was 

evaluated on 2-yr old lemon trees. Spray applications were carried out weekly from May to June, for a total of 

6 treatments per year. Results suggest that OPs could be substituted, or at least alternated, with IGRs and BT. 

Starting from 2006, pheromone traps (Z-7 tetradecenale) were placed in lemon plots and the infestation level 

on flower, young fruits and new shoots was recorded. All set of data produced a robust correlation (r 2 = 0.82) 

between male captures and infestation percentage. Depending on the economic target chosen, a maximum 

level of 120 captures/trap per week could be set as the action threshold. 

S16P35 

Biology of Citrus Fruit Borer, Citripestis sagittiferella Moore and its control. 

Srijuntra S., Manusmunkong B., Sahaya S., Jumroenma K., and Srikachar S. 

Plant Protection Research and Development Office), Department of Agriculture, Thailand. nutaa2000@yahoo.com 

Studies on the biology of the citrus fruit borer, Citripestis sagittiferella Moore were carried out at the 

laboratory of Entomology and Zoology Research Group, Plant Protection Research and Development 

Office, Bangkok, and pummelo orchards at Trat and Chumphon province during October 2005 to April 

2007. Results showed that females lay eggs in clusters (2-29 eggs) on the fruit at night. The egg is round in 

shape and white in color. The incubation period is 5.30±0.87 days. The larvae of C. sagittiferella molt four 

times and total larval stages last 14.60±0.52 days. The growth increment of larvae based on the width of 

head capsules assumed a geometric progression with a ratio of 1.61. The final instar larva pupates in the 

soil and requires 6.77 ± 1.88 and 5.83±1.54 days for male and female, respectively, to reach adulthood. 

The longevity of adult male and female are 5.72±1.18 and 5.88±1.24 days, respectively. The survey of C. 

sagittiferella natural enemies yielded one species, Trichogrammatoidea sp., an egg parasitoid. Damaged 

and fallen fruit should be removed from orchards to control this moth. Infested areas should be sprayed 

with insecticides four times on a weekly basis after fruit setting. Then fruit should be wrapped to prevent 

infestation by C. sagittiferella. 

S16P36 

Spirotetramat (Movento®): a new tool for Aonidiella aurantii Maskell management in Spain. 

Izquierdo J., and Fullana J. 

Bayer CropScience, Spain. josep.izquierdo@bayer.com 

Spirotetramat (Movento®) is a new insecticide (full translocation in xylem and phloem) which has been 

developed for worldwide use in numerous crops. Spirotetramat is listed in Group 23 of the IRAC (Insecticide 

Resistance Action Committee) mode-of-action classification scheme as an inhibitor of lipid biosynthesis in 

targeted pest species. It displays a completely new mode of action for control of several sucking insect pests 

which are known to seriously damage agricultural crops. California red scale (CRS), Aonidiella aurantii Maskell 

(Hemiptera: Diaspididae), is a key pest of citrus in the Mediterranean basin where it is widely distributed. 

Despite the few available insecticides, chemical control is still the commonest method used against this pest. 

Herein, we show the efficacy of spirotetramat against CRS in citrus and enhance some of its advantages for 

the practice. Spirotetramat showed high levels of efficacy against CRS in the numerous field trials carried 

out in Spain since 2002. Several characteristics of spirotetramat explain these results. The foliar penetration 

is of utmost importance to allow the transport of the product in the plant vascular system and to exploit its 

full biological potential. The phloem-mobile molecule like spirotetramat, acting mainly via ingestion, favours 

the control of hidden targets as CRS in comparison to contact products. Spirotetramat affected all immature 

stages of CRS offering an interesting flexibility in the application periods according to the specific targets and 

needs of the growers. 

Finally, the low impact of spirotetramat on key natural enemies in citrus allows the inclusion of this product 

in IPM programs where biological control is promoted and improves the results by the integration of 

methods. 


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S16P37 

Carbendazim, mancozeb and pyraclostrobin residues resulting from the chemical control of black 

spot (Guignardia citricarpa) in Valencia oranges in NE 

Kulczycki Waskowicz C. 1 , Sosa A. 1 , Becerra V. 2 , Navarro R. 2 , Burdyn L. 1 , Garran S.M. 1 , and Mousqués J. 1 

1 National Institute of Agricultural Technology, Concordia Agricultural Experiment Station (INTA, EEA Concordia), Pesticides Residues 

Plant Protection, Argentina; and 2 National Institute of Agricultural Technology, Mendoza Agricultural Experiment Station INTA (INTA, 

EEA Mendoza), Phytopharmacy Study Center, Argentina. ckulczycki@correo.inta.gov.ar 

Black Spot, a severe disease caused by the fungus Guignardia citricarpa Kiely affects citrus orchards decreasing 

both yield and fruit quality. Chemical control using different fungicides is the most effective control method. 

However, legal and food safety requirements make imperative to know actual level of pesticide residues at 

harvest. The objective of this study was to determine fungicide residue levels on ripe orange fruit resulting 

from different chemical control programs. Trials were conducted on a commercial orchard of Valencia 

oranges, using a randomized four blocks design where four different fungicide treatments besides the control 

were tested. The fungicides mancozeb, pyraclostrobin, and carbendazim, were applied at different times, 

from October 2009 to April 2010. Once fruit reached commercial maturity as required, in October 2010, fruit 

samples were collected and immediately processed. Pyraclostrobin and carbendazim residues were analyzed 

using liquid chromatography (detection limits of 0.03 mg/kg and 0.02 mg/kg, respectively). Mancozeb was 

analyzed by a colorimetric method based on a process of spectrometric quantification of CS2 (detection limit 

0.1 mg/kg). In all cases, residues were below detection limits. 

S16P38 

Evaluation of a novel insecticide, DPX-HGW86 10% OD (Benevia) and DPX-HGW86 20% SC 

(Verimark), for Diaphorina citri (Hemiptera: Psyllidae) control. 

Miranda M.P., Felippe M.R., Garcia R.B., Caldeira R.E., and Noronha Jr N.C. 

Fundecitrus (Fundecitrus), Scientific Department, Brazil. mpmiranda@fundecitrus.com.br 

Diaphorina citri is the vector of huanglongbing in Brazil and elsewhere. Insecticidal control is the primary 

tactic against this insect. Rotation of insecticidal modes of action is important to avoid psyllid resistance and 

therefore new chemistry is for management of this pest. Thus, this research was carried out to evaluate the 

efficacy of DPX-HGW86 formulated either as a 10%OD (Benevia) or a 20%SC (Verimark). These products 

represent a novel diamide chemical class of insecticide for D. citri control either as a foliar spray or drench 

application respectively. For the foliar spray trial, citrus nursery trees with fully expanded leaves were treated 

with the following products and doses (ml commercial product/100L water): Benevia at 50, 75, 100 and 

125ml; imidacloprid 20%SC at 20ml and Lambda-cyhalothrin 5%CS at15ml. For the drench application trial, 

nursery trees with new shoots were treated with Verimark at 1.75, 3.5, 7ml commercial product/plant and 

imidacloprid 20%SC 1.75ml c.p./plant. Both experiments were conducted in a greenhouse. Mortality was 

assessed every week up to 50 days after application (DAA) for spray treatments, and for drench treatments up 

to 104 DAA. Both applications resulted in good efficacy (mortality≥80%) against D. citri adults, similar to the 

standard treatments. The systemici activity observed with Verimark is important because presently, only 

the neonicotinoid class is available with this feature for adult psyllid control. Therefore, both Benevia and 

Verimark will be useful for insecticide resistance management. 

S16P39 

Effects of foliar applications of pyrethroid and neonicotinoid insecticides on the populations of 

Panonychus citri (McGregor, 1916) (Acari: Tetranychidae) in laboratory. 

Zanardi O.Z., Rugno G.R., Bordini G.P., Beloti V.H., and Yamamoto P.T. 

Escola Superior de Agricultura Luiz de Queiroz (ESALQ), Entomologia e Acarologia, Brasil. gabrielrugno@hotmail.com 

Overuse of pyrethroids and neonicotinoid insecticides could be one a cause of outbreaks of Panonychus citri 

(McGregor, 1916) in citrus orchards. This work investigated the effect of foliar application of these insecticides 

on intrinsic rate of increase (r i ) of P. citri in the laboratory. Treatments and doses (g a.i./100 L) evaluated 


were: esfenvalerate (0.25); deltamethrin (0.75); lambda-cyhalothrin (1.0); imidacloprid (4.0); thiamethoxam 

(2.5) and control (distilled water). Citrus seedlings 30 cm in height with eight fully-developed leaves where 

sprayed. After residues dried, two newly emerged P. citri females were placed on each leaf. The plants were 

placed in a room with controlled temperature at 25±2°C, RH 70±15% and photophase of 14h. The design was 

completely randomized with five treatments and three replications. Results were evaluated 28 days after 

application by counting all living individuals. Intrinsic rate of increase was determined by the equation r i = [ln 

(N f / N 0 )/Δt], where: N f = final number of individuals, N 0 = initial number of individuals and Δt = duration of 

experiment. The r i ranged from 0.014 to 0.054, not significantly different among treatments. These results 

suggest that the insecticides evaluated did not affect the mite population, being, therefore, one of the causes 

for the outbreak population of P. citri. 

S16P40 

Side effects of some pesticides under field conditions on important parasitoids and predators in 

citrus ecosystem 

Simsek V.M. 1 , Uygun N. 2 , and Satar S. 2 

1 Bayer CropsScience (BCS), Bayer CropsScience, Adana-Turkey; and 2 Çukurova University (ÇU), Department of Plant Protection, Adana 

- Turkey. hserhat@cu.edu.tr 

Side effects of pyriproxyfen, buprofezin, chlorpyrifos-ethyl, spirotetramat, mineral oil and paraffinic mineral oil 

on some predators and parasitoid were investigated in a 12 years old orange orchard infested with Panonychus 

citri (McGregor) (Acari: Tetranychidae) and a 16 years old lemon orchard infested with Aonidiella aurantii 

(Maskell) (Hemiptera: Diaspididae). Trials were carried out under field conditions in 2008 and 2009 for P. citri 

and 2007 and 2008 for A. aurantii. All treatments were replicated four times in a randomized block design. 

After insecticide treatment, predators were collected with Steiner funnel and parasitoids for A. aurantii were 

obtained by collecting plant materials at -1st, 7th, 14th and 21st days for both years. Effects of pesticides were 

classified according to IOBC standards. Chilocorus bipustulatus (L.) (Coleoptera: Coccinellidae) (74.31%) and 

Aphytis melinus DeBach (Hymenoptera: Aphelinidae) (>90%) for A. aurantii infested orchard, and Stethorus 

gilvifrons (Mulsant) (Coleoptera: Coccinellidae) (85.06%) for P. citri infested orchard were recorded as main 

predators and parasitoid in 2007 and 2008. The side effects of the pesticides on predators of P. citri were 

found statistically significant for both years, but they were found moderately harmful (51-75%) for IOBC 

field evaluation. Similar results were also obtained from A. aurantii infested orchards, as predators were 

affected from pesticide at statistically different level. The lowest populations reduction was calculated for 

spirotetramat (45.8% for 2007, 55.1% for 2008) and paraffinic mineral oil (45.8% for 2007, 54.3% for 2008), 

while the highest level of reduction in predators populations were observed in chlorpyrifos-ethyl (91.7% for 

2007, 87.9% for 2008) and pyriproxyfen (91.7% for 2007, 85.6% for 2008). Although effect of pesticides on A. 

melinus were statistically different from each other, all pesticides were grouped as moderately harmful (51- 

75%) or harmful (>75). 

S16P41 

Side effects of some pesticides under laboratory conditions on important parasitoids and 

predators in citrus ecosystem. 

Simsek V.M. 1 , Uygun N. 2 , and Satar S. 2 

1 Bayer CropsScience (BCS), Bayer CropsScience, Adana-Turkey; and 2 Çukurova University (ÇU), Department of Plant Protection, Adana - 

Turkey. mehmet.simsek@bayer.com 

The laboratory tests were conducted to evaluate side effect of insecticides pyriproxyfen, buprofezin, 

chlorpyrifos-ethyl, spirotetramat, mineral oil, paraffinic mineral oil and spinosad on Aphytis melinus DeBach 

(Hymenoptera: Aphelinidae), Leptomastix dactylopii Howard (Hymenoptera: Encyrtidae), Cryptolaemus 

montrouzieri Mulsant (Coleoptera: Coccinellidae) and Sympherobius pygmaeus (Rambur) (Neuroptera: 

Hemerobiidae). Contact toxicities of insecticides on beneficials and their progenies were monitored under 

guidelines of IOBC. According to IOBC classification, pyriproxyfen was harmless on A. melinus, L. dactylopii 

and C. montrouzieri adults and harmful on C. montrouzieri and S. pygmaeus larvae; buprofezin showed similar 


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result except S. pygmaeus larvae; chlorpyrifos-ethyl was harmful on all parasitoids and predators except C. 

montrouzieri larvae and adult; spirotetramat was harmless on parasitoids and predators except A. melinus, it 

slight harmful on it; mineral oil was harmless on L. dactylopii and C. montrouzieri adults, slightly harmful on 

A. melinus adult, C. montrouzieri and S. pygmaeus larvae; paraffinic mineral oil was harmless on A. melinus, 

L. dactylopii and C. montrouzieri larvae-adults, and slightly harmful on S. pygmaeus larvae; Spinosad was 

harmless on C. montrouzieri larvae-adults and S. pygmaeus larvae, moderately harmful on L. dactylopii and 

harmful on A. melinus. The progeny production of each surviving beneficial treated with spirotetramat at adult 

and larval stages were not affected by treatment and similar results were also observed pyriproxyfen and 

buprofezin except larval stage of predators, meanwhile spinosad has slightly effect on fertility of predators. 

The adult or larval stages of C. montrouzieri have slightly reduced number of progeny after chlorpyrifos-ethyl 

treatment. 

S16P42 

New book on citrus pests: “Citrus pests. Integrated pest management in countries of 

Mediterranean climate” (Plagas de los cítricos. Gestión integrada en países de clima 

mediterráneo). 


Universitat Politècnica de València (UPV), Instituto Agroforestal Mediterráneo, Spain. fgarciam@eaf.upv.es 

This book, in Spanish and appearing in October 2012, includes published information on citrus pests 

throughout the world in general, and particularly from Mediterranean countries. It gathers and synthesizes 

in a descriptive way the up to date knowledge on pest identity, morphology, biology, seasonal cycle and 

management methods, including sampling methods, treatment thresholds and the main natural enemies, 

as well as chemical and biological control. The book includes 180 color plates, with more than 1,200 

pictures, to help recognize the most important phytophagous arthropods which affect the crop, their 

symptoms and damage, and their most relevant natural enemies. On the other hand, the book includes 

an analytical study, from a demographic point of view, of the pest situation in citrus crops in the east of 

the Iberian Peninsula, discussing the main factors which influence the structure and development of pest 

populations and determine its abundance and evolution. For this purpose, many experimental data from 

samplings and trials are presented in more than 60 tables and near 200 figures. The observations carried 

out have allowed the development of this book which reflects accurately the current situation of arthropod 

pests in citrus crops. 

S16P43 

Impact of pesticides used in citrus orchards on the beneficial insects Cryptolaemus montrouzieri 

Mulsant 

Rahmouni R., and Chermiti B. 

High Agronomic Intitute of Chott-Mariem (ISACM), Laboratory of Entomology and Biological Control, Tunisia. 

chermiti54@yahoo.fr 

Adults and larvae of Cryptolaemus montrouzieri Mulsant, a predator of the mealybug Planococcus citri 

Risso, were exposed to direct sprays and to leaf discs treated with Malathion, Acetamiprid, Cyhexatin, 

Tetradifon, Methidathion, and Spinosad. Active substances were very toxic when directly sprayed on larvae 

with mortality rates around 80.0% except for Spinosad, which was less toxic (39.0% mortality). Direct spray 

of adults caused mortality rates of 100% for Acetamiprid and 18.8% for Spinosad. On treated leaf discs, 

larval mortality rates varied between 73.0 and 84.0% except for Spinosad that showed 48.0% mortality 

only. In relation to adults, only Acetamipride and Methidathion were very toxic with mortality rates higher 

than 70.0%, whereas Malathion, Cyhexatin Tetradifon and Spinosad caused mortalities of 47.5, 31.0 and 

18.8%, respectively. 


S16P44 

Preliminary survey of the Green Lacewings (Neuroptera, Chrysopidae) in citrus orchards in 

Northern east of Tunisia (Cap Bon). 

Limem Sellami E., and Chermiti B. 

Higher Agronomic Institute of Chott-Mariem (ISACM), Laboratory of Enomology and Biological Control, Tunisia. 

chermiti54@yahoo.fr 

Aphids are one of the key pests affecting citrus in Tunisia. Nowadays, their control is mostly chemical. 

However, because of the need for a more sustainable citrus industry, other biologically-based control 

methods are under study. One of them involves the biological control by means of natural enemies. As a 

first step, increased knowledge on the actual diversity of-natural enemies in this citrus system is needed. 

Because lacewings (Neuroptera: Chysopidae) are one of the most important group natural enemies of aphids, 

a survey of lacewings occurring in citrus orchards in NE Tunisia (Cap Bon) was conducted. 3 organic-and 

4 conventional citrus orchards were compared during two consecutive years (2010, 2011). Adults were 

collected with avacuum aspirator; whereas pre-imaginal instars were collected from aphid infested shoots. 

Six green lacewing species were identified: Chrysoperla lucasina, C. carnea, C. affinis, Dichochrysa flavifrons, 

Dichochrysa prasina and Chrysopaformosa. C. lucasina-was the dominant species (53%) in all orchards. 

Adults of the complex C. carnea were recorded-from February to December and showed two peaks-in May- 

June and in September. The occurrence of pre-imaginal instars is related to aphid activity. Diversity of green 

lacewing is generally low (H’= 1.27). However, Shannon index was highest in organic orchards. Dominance 

and equitability index (respectively 0.8 and 0.2) showed a dominance of the C. carnea complex in all orchards. 

This species could be managed for the biological control of aphids in citrus orchards. 

S16P45 

Mating disruption technique as a control method for California red scale: a review of doses, 

efficacy and date of application 

Navarro-Llopis, V., Alfaro C., Vacas S., and Primo Millo J. 

Instituto Agroforestal del Mediterráneo (CEQA). Universitat Politècncia de València. vinallo@ceqa.upv.es 

California red scale, Aonidiella aurantii Maskell, is a key pest for citrus fresh market around the world. 

Chemical control with organophosphates, insect growth regulators or oils has been widely used, although the 

increasing resistance to organophosphates, the effect of IGR over non-target organisms and the difficulties in 

applying oils suggest the development of other IPM control methods. In the present work, the use of mating 

disruption is proposed as a new control method which can be applied alone or combined with other methods. 

The pheromone dose, the number of release points per surface and the date of application have been studied 

for an efficient application of the mating disruption technique. The importance of emitting the pheromone 

with zero order kinetics is well known in mating disruption. For this purpose, we designed a new mesoporous 

dispenser that releases the pheromone in an efficient way during more than 150 days. After 6 years of studies, 

results suggest a minimum dose of 35 g of pheromone ha-1, a minimum density of 450 dispenser ha-1 and 

the application of dispensers just before the second male’s flight. In these conditions, an efficacy of at least 

90% was obtained in field trials, taking special importance to the reduction in the percentage of fruit with 

more than 5 scales. The effect of this method over A. aurantii parasitoids was also studied suggesting a total 

compatibility of augmentative releases and mating disruption. 

S16P46 

Physiological selectivity of insecticides used for control of Diaphorina citri (Kuwayama, 1908) on 

larvae of Ceraeochrysa cubana (Hagen, 1861). 

Rugno G.R., Zanardi O.Z., Beloti V.H., Cunha R.A., Barbosa V.G., Parra J.R.P., and Yamamoto P.T. 

Escola Superior de Agricultura Luiz de Queiroz (ESALQ), Entomologia e Acarologia, Brasil. gabrielrugno@hotmail.com 

This study investigated the effect of 11 insecticides used for control of Diaphorina citri (Kuwayama) on the 

larval survival of Ceraeochrysa cubana (Hagen). First instar lacewing larvae 48 h old were sprayed using 


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a Potter spray tower (spray deposit 1.9 mg /cm 2 ). After application, larvae were placed in flat-bottomed 

glass tubes and held at 25±2°C, 70±15% RH and 14 h photophase and fed eggs of Anagasta kuehniella 

(Zeller). Experimental design was completely randomized with four replicates and 10 larvae/replicate. Larval 

survival was assessed 24 h after application and categorized according to the IOBC/WPRS classification. The 

insecticides azadirachtin (AzaMax ® ), imidacloprid (Evidence 700 WG ® ) and phosmet (Imidan 500 WP ® ) were 

classified as innocuous to C. cubana (Class I, 99%). 

S16P47 

Distribution of the Asian citrus psyllid, Diaphorina citri (Hemiptera: Psyllidae) in Iran 

Parsi F. 1 , Manzari S. 2 , Askari M. 3 , Amin G. 4 , Ranjbar S. 5 , and Naseri M. 6 

1 Iranian Research Institute of Plant Protection (IRIPP), Agricultural Entomology, Iran; 2 Iranian Research Institute of Plant Protection 

(IRIPP), Insect Taxonomy, Iran; 3 Agricultural and Natural Resources Research Center of Hormozgan, Agricultural Entomology, Iran; 

4 Agricultural and Natural Resources Research Center of Fars, Agricultural Entomology, Iran; 5 Agricultural and Natural Resources 

Research Center of Jiroft and Kahnouj, Agricultural Entomology, Iran; and 6 Agricultural and Natural Resources Research Center of 

Kerman, Agricultural Entomology, Iran. farparsi@yahoo.com 

The Asian Citrus Psyllid Diaphorina citri Kuwayama, is one of the most important pests of citrus orchards 

in Iran. The insect transmits the pathogen that causes citrus greening disease. It was firstly discovered in 

Balouchestan province by Bove in 1999. In order to manage and conduct a programme to control Greening 

disease, it is necessary to have distribution information on D. citri. Hence, its different populations were 

monitored in 8 provinces in the north and south Iran from 2010 t0 2011. Over 2,300 records have been 

established by GPS and data mapped in ArcGIS9.3.1. A distribution map based on two samplings per year 

is presented. The ACP was found in Kerman, Balouchestan, Fars and Hormozgan provinces but not in Gilan, 

Mazandaran, Khozestan and Boushehr. In 2010, D. citri was discovered in Fars province and one year later the 

population was found to be expanded significantly. 


Session 17 

VARIETIES 

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S17O01 

New citrus variety evaluation in Australia 2005-2012 

Sanderson G. 1 , Creek A. 2 , Lacey K. 3 , and Wallace M. 4 

1Dareton Primary Industries Institute (DPII), NSW Department of Primary Industries, Australia; 2Centre for Irrigated Agriculture, 

Griffith (CIA), NSW Department of Primary Industries, Australia; 3Intensive Plant Research Branch (IPR), West Australian Department 

of Food and Agriculture, Australia; and 4Orchard Monitoring Services (OMS), Citricare, Australia. graeme.sanderson@dpi.nsw.gov.au 

Evaluating new citrus varieties is a national project in Australia led by the New South Wales Department 

of Primary Industries (NSW DPI) and is a continuance of the Australian Citrus Improvement Program. This 

long term program is an industry driven initiative aimed at maintaining productivity and profitability. A 

cooperative agreement was developed between NSW DPI, Horticulture Australia Ltd (HAL), Auscitrus and 

local variety managers of Plant Breeders Rights (PBR) varieties to undertake independent evaluation from 

2005 to the present. Thirty one new varieties were included in the evaluation and their performance 

assessed in the major citrus growing regions of Australia. The varieties are predominantly mandarin and 

mandarin hybrids and 20 of the 31 have PBR protection. Varieties have been progressively released from 

Australian Post Entry Plant Quarantine with the final variety being field established in November 2011. 

Evaluation activities include standard fruit quality and yield determination as well as providing larger 

volumes of fruit from topworked trees to approved agents for test marketing. Evaluation site visits to view 

PBR varieties are organised in conjunction with variety managers and fruit displays provided in the major 

citrus regions of Australia. New variety managers are encouraged to become part of the program and seven 

new varieties were included in 2011. The Australian Citrus Industry’s ‘Strategic Research and Development 

Plan 2012-2017’ recognises the need for continued evaluation of new citrus introductions and on-going 

funding will be sort from Horticulture Australia Ltd to continue the program. 

S17O02 

‘Sweet Sicily’ and ‘Early Sicily’, two new triploids from the program of CRA-ACM, Centro di- Ricerca 

per l’Agrumicoltura e le Colture Mediterranee, Acireale, Italy 

Russo G., Reforgiato Recupero G., Recupero S., and Pietro Paolo D. 

Centro di Ricerca per l’Agrumicoltura e le Colture Mediterranee (CRA-ACM), Italy. giuseppe.russo@entecra.it 

The development of triploid hybrids by crossing a monoembryonic 2x female parent with a 4x male parent 

has been the successful breeding strategy carried out by the CRA-ACM since 1978. Through this strategy 

hybrids issued in the past allowed the obtainment of seedless fruits, in some cases pigmented, of good 

size, mature in different periods. In 2011 other two promising hybrids, ‘Sweet Sicily’ and ‘Early Sicily’, due 

to their positive characteristics, were released. The former was obtained by the cross ‘Comune´ clementine 

X 4x ‘Tarocco’ sweet orange, the latter by the cross ‘Oroval’ clementine X 4x ‘Tarocco’ sweet orange. The 

fruits of these hybrids, very early in ripening time (mid-November) showed a fresh market suitable fruit size, 

excellent organoleptic properties and a typical taste intermediate between the clementine and ‘Tarocco’ 

orange. 

S17O03 

Comparison of performance of different late-maturing navel selections around the world. 

Rabe E. 1 , Turner P. 2 , and Chavarria J. 3 

1BiogoldUSA and Paramount Citrus, California, USA; 2Biogold International, South Africa; and 3BiogoldEM, Spain. 

erabe@paramountcitrus.com 

During the late 1980’s and early 1990’s, a number of late navel selections of Australian origin were 

commercialized around the world. In addition to the earlier-discovered and distributed ‘Lane Late’ 

selection, the newer Australian selections included: ‘Barnfield’, ‘Powell’, ‘Autumn Gold’, ‘Chislett’ and a 

host of other’s, most originating from the ‘Lane Late’. Data including acreage levels, yield, internal quality, 

pick dates and general industry perspectives from various production regions will be presented. Regions 


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included represent California, South Africa, Spain, Australia and Chile. In general, yields have been suboptimal 

in certain regions due to late picking, especially in California, fruit sizes have been too large, 

granulation prevalent and general profitability not desirable. Lately, a number of new late-maturing 

selections have been found in South Africa. These include ‘Cambria’ (commercialization have commenced 

already), ‘Witkrans’, ‘Glen Ora’, and ‘Karninka’. Initial internal quality and maturity data will be presented. 

Although, in South Africa, these selections have not been picked as late relative to what the practice is in 

California, the characteristics claimed include better return crops, smoother rinds and even later hanging 

ability, as compared to the Australian selections under similar conditions. In California, late navels are 

expected to hang into May and June, past the next season bloom period, ie up to 14 months after flowering 

and set. There is thus a distinct commercial gap for late selections with better cropping behavior, a smaller 

size manifest, retaining juice levels, less granulation and smoother rinds. The new South African late navel 

selections are seen as possibly meeting some of these requirements. 

S17O04 

Three new varieties of clementine: ‘Clemenverd’, ‘Nero’ and ‘Iviaman1957’ 

López-García A., Terol J., Tadeo F.R., Herrero A., Ibáñez V., and Talón M. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Genómica, Spain. talon_man@gva.es 

The Genomics Center (Instituto Valenciano de Investigaciones Agrarias) has generated in recent 

years various collections of citrus varieties. One objective of these collections is the selection of 

genotypes of commercial interests. In the present communication we described 3 lines derived from 

clementine mandarin (Citrus clementina) through physical mutagenesis, called ‘Clemenverd’, ‘Nero’ and 

‘Iviaman1957’. These lines that show enhanced agronomic traits as related to the parental genotype have 

already been registered. Thus, ‘Clemenverd’ shows a delayed striking external maturation. ‘Nero’ is an 

early variety of seedless clementine that maintains the excellence proper to clementine. On the other 

hand, ‘Iviaman19571’ shows well into February, commercial organoleptic qualities similar to the parental 

‘Clemenules’. ‘Iviaman19571’ also has excellent perdurability in the tree, making it an ideal option to 

extend the supply of clementines during winter. These 3 varieties have good production and post-harvest 

conditions and do not develop spines. 

S17O05 

Relationship between sensory and physico-chemical quality parameters of ‘Lane Late’ with 

Protected Geographical Indication 

Duarte A. 1 , Mendes S. 2 , Nunes S. 2 , Sustelo V. 2 , and Gomes C. 3 

1Institute of Mediterranean Agricultural and Environmental Sciences, University of Algarve (ICAAM/UAlg), Faculty of Sciences and 

Technology, Portugal; 2University of Algarve (UAlg), Faculty of Sciences and Technology, Portugal; and 3Direção Regional de Agricultura 

e Pescas do Algarve (DRAPALG), Portugal. aduarte@ualg.pt 

The determination of the optimal harvest time is extremely important in order to obtain a product of high 

quality, highly valued by the market. This is particularly important when the production is covered by a 

certification system. This paper establishes a relationship between physico-chemical quality parameters 

(soluble solids content, titratable acidity, maturity index, and others) and the acceptance of the fruits by 

a panel of consumers. The study was conducted over three months in two orchards of ‘Lane Late’ sweet 

orange with different climatic conditions. The assessment by consumers is related to the evolution of the 

maturity index. However, consumer preferences may be very different. Fruits with the same maturity 

index can be regarded as too acid for some consumers, while others consider them too sweet. On the 

other hand it was concluded that some consumers have a high requirement level for fruit tagged with 

Protected Geographical Indication “Citrus of Algarve.” In some cases we found that although the fruits 

presented a high quality does not correspond to what consumers consider should be required for a 

“Citrus of Algarve”. 


S17O06 

New promising citrus hybrids for the ornamental use 

Recupero S., Russo G., and Reforgiato Recupero G. 

CRA- Centro di Ricerca per l’Agrumicoltura e le Colture Mediterranee (CRA-ACM), Italy. giuseppe.reforgiato@entecra.it 

In Italy for the production of ornamental citrus lemon (Citrus limon), ‘Oval’ kumquat (Fortunella margarita), 

‘Calamondin’ (C. madurensis) and ‘Small leaf’ chinotto (C. myrtifolia) represent the most utilized species. 

Considering that the market offer is increasing also in others competitor’s countries, there is the risk of a 

surplus of production. So is very important for revitalizing the market the availability of new genotypes. In 

2002 the CRA-ACM started a breeding program with the intent to produce new genotypes with favourable 

and variable ornamental traits. Two new genotypes showing interesting ornamental characteristics recently 

released are reported. The former is a hybrid obtained by cross of ‘Meyer’ lemon and a blood orange, showing 

original striped fruits as an apparent form of orange-over-red periclinal chimera. In 2012 this genotype was 

proposed for the Italian patent. The latter is a chance seedling of ‘Oval’ kumquat, showing small, rounded, 

yellow and very fragrant fruits. Due to its late blooming fruits persist on the trees until the late summer, when 

other genotypes are not able to maintain fruits on the tree. 

S17O07 

‘Meirav’ seedless, a new promising Israeli mandarin: effects of rootstocks and growth regulators 

on yield and fruit quality 

Kanonich Y.K., Holsman S.H., Oren Y.O., Kaplan I., Tagari E., Fainzack M., and Giladi B. 

Ministry of Agriculture Extension Service, Israel. shukan@shaham.moag.gov.il 

‘Meirav’ seedless mandarins naturally ripen from December till late January. The fruit are entirely seedless, 

have an attractive orange/red color, and are very tasty and easy to peel. The variety was tested during 4 

consecutive growth seasons for yield, fruit size and quality on 4 different rootstocks: ‘812’, sour orange, ‘C-35’ 

and ‘Volkameriana’ in two different climates in the desert and coastal areas. The rootstocks ‘812’ and sour 

orange were most preferred regarding their effects on fruit quality. In the desert area, TSS and acid levels on 

‘812’ and sour orange rootstocks were ~12.0% and ~0.85%, respectively, and the annual average yield was 39 

ton/ha. ‘Volkameriana’ rootstock provided a higher average yield of 58 ton/ha, but fruit internal quality was 

poor, and TSS and acid levels were just 10.9% and 0.7%, respectively. In the coastal area, ‘812’, sour orange 

and ‘C-35’ rootstocks had more or less similar effects on yield (3.8-4.1 ton/ha), TSS (13.6-13.7%) and acidity 

levels (0.94-1.08%). However, the ‘C-35’ rootstock caused severe scion-rootstock incompatibility observed 

already after 7 years. Double sprays with Naphthalene acetic acid (NAA, 300 mg/L) combined with ‘Bonus- 

NPK’ fertilizer (4%) on medium size fruitlets (16 and 20.5 mm in diameter), did not affect fruit thinning, but 

significantly increased fruit size and consequently total yield. Overall, our data suggest that ‘812’ and sour 

orange are the preferable rootstocks for ‘Meirav’ seedless mandarin due to their positive effects on yield and 

fruit quality. NAA treatments further increased fruit size and yield. 

S17O08 

How many seeds are acceptable in commercial citrus varieties derived from irradiation? 

Williams T.E. 

University of California Riverside (UCR), Botany and Plant Sciences, United States. timwill@ucr.edu 

Mutation breeding, specifically through the use of irradiation directed at reducing seed numbers in normally 

high-seeded varieties, has resulted in the production and release of a number of new varieties from various 

citrus breeding programs. The goal of these breeding efforts, quite obviously, has been to achieve zero seeds 

under all conditions of cross pollination in the irradiated selection. But is this necessary for commercial 

success in new varieties developed from irradiation, or can low seed counts, in the 1-3 mean seed/fruit range, 

fulfill commercial expectations for specific varieties?. This presentation will explore current experiences with 

commercially released varieties developed using irradiation, explore the importance of seed count in relation 

to other specific fruit quality characteristics and suggest some useful breeder guidelines for future selections. 


S17

S17 

S17P01 

Plant growth, initial fruit production and yield efficiency of twelve early maturing sweet orange 

cultivars in São Paulo State, Brazil 

Caputo M.M. 1 , Mourão Filho F.A.A. 1 , Silva S.R. 1 , Stuchi E.S. 2 , and Bremer Neto H. 1 

1 Universidade de São Paulo (USP), Produção Vegetal, Brazil; and 2 Embrapa Mandioca e Fruticultura (EMBRAPA), Estação Experimental 

de Citricultura de Bebedouro, Brasil. marinamaittocaputo@hotmail.com 

One alternative to minimize the effects of highly destructive diseases on sweet oranges used for industrial 

processing is the establishment of new plantings in regions of less incidence, such as the Southwestern São 

Paulo State, Brazil. However, the different sweet orange cultivars have distinct vigor which can influence tree 

growth and development and, consequently, affect production. The objective of this study was to evaluate 

the plant growth, initial fruit production and yield efficiency of twelve early maturing sweet orange cultivars 

(Citrus sinensis) grafted on ‘Sunki’ mandarin (C. sunki) and identify those superior to ‘Hamlin’, the main early 

maturing cultivar planted in São Paulo State. The sweet orange cultivars evaluated were ‘Hamlin’, ‘Westin’, 

‘Pineapple’, ‘Ruby’, ‘Seleta Vermelha’, ‘Mayorca’, ‘Valencia 2’, ‘Olivelands’, ‘Kawatta’, ‘IAPAR 73’, ‘Salustiana’ 

and ‘Valencia Americana’. The experimental design was completely randomized with four replications, 

consisting of three plants of each cultivar per plot. Data of plant growth (plant height, canopy diameter and 

volume), fruit production and yield efficiency collected on 2010 and 2011 harvest seasons were obtained 

and analyzed by Dunnett test (P

to 1980. These genotypes were examined for 22 pomological and four plant characteristics. Fruits were 

harvested at optimal maturation stage and yield/tree rates were calculated individually. Selections of 20 

nucellar oranges, which were named as ‘Hamlin (14-17)’, ‘Hamlin (14-15)’, ‘Magnum Bonum’, ‘Trovita (A- 

35)’, ‘Parson Brown’, ‘Portakal (P-24)’, ‘Portakal (P-28)’, ‘Shamouti WN’, ‘Yafa (14-4)’, ‘Yafa (A-21)’, ‘Balady’, 

‘Madame Vinous’, ‘Dörtyol Yerli’, ‘Pineapple’, ‘Barile’, ‘Kozan Yerli’, ‘Biondo’, ‘Biondo Ricco’, ‘Paperrind’ 

and ‘Valencia’ were evaluated in terms of their yield and fruit quality characteristics. Nucellar plants are 

very important because they have the same genetic characteristics of their mother plants and are free of 

most viruses. Among the results generated, it was found that ‘Hamlin (14-15)’, ‘Balady’, ‘Madame Vinous’, 

‘Trovita (A-35)’ and ‘Valencia’ were very promising. 

S17P04 

Yield and fruit quality of two early maturing orange cultivars, ‘Navelina’ and ‘Fukumoto’, in 

Andalusia (Spain) 


Instituto de Investigación y Formación Agraria y Pesquera (IFAPA), Cítricos, Spain. carlos.merino.luna.ext@juntadeandalucia.es 

Spain has positioned itself as the sixth largest producer of citrus fruit and the number one exporter worldwide. 

However the profitability of Spanish citrus orchards is threatened by the globalization of markets which has 

led to Spanish citrus growers to be interested in new citrus cultivars in order to obtain greater profits and 

to be more competitive by improving some aspects of the crop and marketing such as productivity and fruit 

quality, and avoiding the concentration of the supply. This study was carried out to evaluate the yield and fruit 

quality of ‘Navelina’ and ‘Fukumoto’, two early ripening sweet orange cultivars, in Andalusia (Spain). During 

the 2010/2011 season, yield and fruit quality: size, weight, shape and external fruit colour, juice content, 

total soluble solids concentration, total acids concentration and soluble solids/acid ratio were evaluated in a 

experimental field, located in western Andalusia (Huelva), planted in June, 2006, in a radomized block design, 

with ‘Carrizo’ citrange as rootstock and ‘Valencia Late Frost’ as interstock, thus being a double-budded 

plantation. The results showed significant difference between ‘Navelina’ and ‘Fukumoto’ in fruit quality. Thus 

‘Fukumoto’ induced more attractive fruit colour, while ‘Navelina’ had more rounded fruits, as a result of a 

bigger height. Finally ‘Navelina’ and ‘Fukumoto’ had similar yields. 

S17P05 

Phenological growth stages of oranges and mandarins in Entre Ríos province (Argentina) 

Rivadeneira M. F. 

Instituto Nacional de Tecnología Agropecuaria. Estación Experimental Agropecuaria Concordia (INTA EEA Concordia), Entre Ríos, 

Argentina. frivadeneira@correo.inta.gov.ar 

The objective of this research was to evaluate flowering growth stages and ripening time of commercial 

oranges and mandarins varieties in Entre Ríos, Argentina. The study was carried out in Concordia in a 

plot located at the Estación Experimental Agropecuaria Concordia Instituto Nacional de Tecnología 

Agropecuaria. The observations were made in four trees from 2005 to 2011 growing seasons and flower 

phenology was recorded every two weeks in oranges (‘Newhall’, ‘Lane Late’, ‘Valencia Late’ and ‘Salustiana’), 

mandarins (‘Okitsu’ satsuma and ‘Clemenules’ clementine), and hybrids (‘Ellendale’ and ‘Nova’) grafted 

on trifoliate orange (Poncirus trifoliata) rootstock. Fruit quality was determined at commercial harvest. 

Dates were standardized for ANOVA analysis and means compared with LSD Fisher. Date of full bloom 

was year dependent (p

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S17P06 

Fruit characteristics of some late maturing commercial mandarin cultivars in Spain 

Simón-Grao S. 1 , Simón I. 2 , Lidón V. 3 , Nieves M. 4 , Carbonel A.A. 5 , Manera J. 2 , Hernández F. 3 , and García-Sánchez F. 1 

1 Centro de Edafología y Biología Aplicada del Segura (CEBAS), Plant Nutrition, Spain; 2 Escuela Politécnica Superior de Orihuela 

(EPSO), Física y ATC, Spain; 3 Escuela Politécnica Superior de Orihuela (EPSO), Producción Vegetal, Spain; 4 Escuela Politécnica Superior 

de Orihuela (EPSO), Agroquímica y Medio Ambiente, Spain; and 5 Escuela Politécnica Superior de Orihuela (EPSO), Tecnología 

Agroalimentaria, Spain. fgs@cebas.csic.es 

Spanish’s annual mandarin production is about 2 million tons, of which over the last twenty years the major 

group has been clementines and ‘Clemenules’ in particular. Currently a largely new clementine and other 

varieties are flooding the fruit markets and nurseries. For a citrus grower to choose the right mandarin cultivar 

for a given region or market, it is very important to know the characteristics of that cultivar particularly in 

terms of the development of its internal as well as external quality attributes. In this study we characterized 

the chemical and physical aspect of some late maturing commercial mandarins in the Spanish southeast. 

We analyzed the fruits of the clementine cultivars: ‘Fina’, ‘Clemenules’, ‘Hernandina’; the tangor cultivars: 

‘Ortanique’, ‘Nadorcott’, ‘Mor’ and ‘Ellendale’; and the hybrids cultivars: ‘Fortune’, ‘Kara’, ‘Nova’ and ‘Yosemite’. 

These mandarin cultivars were analyzed for their physical and chemical characteristics. ‘Ellendale’ and ‘Kara’ 

provided the biggest fruit size; on the other hand, ‘Hernandina’ produced the smallest fruits. ‘Ellendale’ also 

showed the highest amount of juice expressed as relative percentage to fruit weight. However, this cultivar 

had the highest number of seed with 9 per fruit, while ‘Nova’ was the mandarin which had not seeds. Relative 

to the juice characteristic, ‘Nova’ and ‘Fina’ clementine enhances by their high SST and low titratable acidity. 

Also ‘Nova’ showed the highest concentration of total phenols. The highest mineral content was observed 

in potassium, with a high concentration in ‘Fina’ clementine. Profile of organic acids, sugars and aromatic 

compounds are also reported. 

S17P07 

Evaluations of early satsuma selections for California 

Kahn T., and Siebert T. 

1 University of California-Riverside (UCR), Botany and Plant Sciences, USA. tracy.kahn@ucr.edu 

The global mandarin market continues to expand as consumers increasingly favor sweet, seedless, and 

easy-peeling varieties. According to the United States Department of Agriculture, acreage of mandarins 

in California has increased from 8,600 acres in 1998-1999 to 33,000 acres in 2010-2011. Satsumas are 

the earliest maturing of all mandarins, but competition in the marketplace with clementine mandarins 

has left growers seeking even earlier maturing satsuma selections. Our research program provides initial 

tree and fruit quality trait evaluations of citrus cultivars introduced into CA from other parts of the world 

to determine which early maturing selections should be considered for further multi-location trials to 

evaluate yield and commercial potential. This study summarizes the results of our fruit quality evaluations 

of 21 satsuma selections introduced into California including ‘Owari’ and ‘Okitsu Wase’ commercial 

standards between 2005 and 2011 sampled from two locations in California three to four times per 

season. Differences among selections were most pronounced for three of the fruit quality characteristics: 

solids: acid ratio, percentage of acidity based citric acid and rind color which are important measures of 

early maturity. 

S17P08 

Yield and fruit quality of two satsuma cultivars, ‘Okitsu’ and ‘Iwasaki’, in Andalusia (Spain) in 

2010/11 season 


Instituto de Investigación y Formación Agraria y Pesquera (IFAPA), Cítricos, Spain. carlos.merino.luna.ext@juntadeandalucia.es 

New citrus cultivars in Andalusia need to be evaluated in experimental fields under local conditions before 

been planted in a large scale as there isn’t a citrus genetics and breeding programme in this region of Spain, 


thus being most new plant material brought from other countries or other parts of Spain, with different 

climate and soil conditions. This experiment has been carried out to evaluate the horticultural performance 

of two early ripening mandarin cultivars, ‘Okitsu’ and ‘Iwasaki’, during the 2010/2011 season, the study 

being focused on both yield and fruit quality components: size, weight, shape and external fruit colour, juice 

content, total soluble solids concentration, total acids concentration and soluble solids/acid ratio. The results 

showed significant differences between ‘Iwasaki’ and ‘Okitsu’. Regarding fruit ripening, ‘Iwasaki’ is about two 

weeks earlier. This cultivar had also greater fruit size, rind thickness and external colour. 

S17P09 

Behaviour of ‘Parana’ grapefruit in the Southeastern region of Paraguay 

Wlosek Stañgret C.R. 1 , and Canteros B.I. 2 

1 Facultad de Ciencias Agrarias de la Universidad Nacional de Asunción, sede Santa Rosa (FCA UNA), Misiones, Paraguay; and 2 Instituto 

Nacional de Tecnología Agropecuaria, Estación Experimental Agropecuaria Bella Vista, (INTA), Corrientes, Argentina. 

fruticultura@trociuk.com 

Citrus cultivation in Southeastern Paraguay had increased in the last years. The region is located between 

25° and 27°S, mean temperature 21°C, records of -2°C and 39°C, annual rainfall 1700 mm, 150-300 m over 

sea level. The weather is favorable to Canker disease that is endemic and limit the growth of grapefruit. The 

objective of this work was to study the adaptation and behaviour of the ‘Parana’ grapefruit, which is highly 

resistant to Citrus Canker. This poorly described variety is planted in the region since 2004. It is registered in 

Paraguay in SENAVE (Servicio Nacional de Calidad y Sanidad Vegetal y de Semillas) under Resolution 857-2011 

in the National Registry of Commercial Cultivars (RNNC) as a grapefruit (Citrus paradisi) variety. More than 

1,500 ha are cultivated and it is a good opportunity to small farmers due to the rusticity, productivity, and 

Canker resistance. The main use is for concentrated juice. The trees are medium size, smaller than ‘Duncan’. 

The main rootstocks are ‘Volkamer’ lemon, ‘Rough’ lemon, ‘Swingle’ citrumelo, and ‘Troyer’ citrange. On 

‘Rough’ lemon the production is 20 kg/tree at the third year and 140 kg/tree after sixth years. On other 

rootstocks the production is 30% less but the quality and quantity of juice is best. The variety is easy managed 

in nursery and orchard, few thorns, some resistance to frost damage, and precocity of fruit production, 

without alternative bearing. The harvest is from March to July, fruits are 8.0 to 8.5 cm in diameter, 280 g per 

fruit, mean of 40 seeds, juice yield of 40%, and high ratio (7.5 to 11.5) at harvest. 

S17P10 

Characterization of grapefruit varieties produced in Argentina and Paraguay 

Sgroppo S.C. 1 , Pereyra M.V. 1 , Wlosek Stañgret C.R. 2 , and Canteros B.I. 3 

1 Facultad de Ciencias Exactas y Naturales y Agrimensura. Universidad Nacional del Nordeste (FCENA UNNE), Corrientes, Argentina; 

2 Facultad de Ciencias Agrarias de la Universidad Nacional de Asunción, sede Santa Rosa (FCA UNA), Misiones, Paraguay; and 3 Instituto 

Nacional de Tecnología Agropecuaria (INTA EEA Bella Vista), Corrientes, Argentina. fruticultura@trociuk.com 

Grapefruit (Citrus paradisi) is an important source of biactive compounds, largely due to the presence of 

flavonoids (naringin, rutin, narigenin, hesperidin and hesperedine), as well as ascorbic acid, carotenoids, etc. 

The naringin is the main flavonoid in grapefruit and is used as a marker of juices. This study has been addressed 

on ‘Dalan dan’ grafted on ‘Troyer’ (CT) and ‘Carrizo’ (CC) citranges and on ‘Duncan’ and ‘Paraná’ varieties. 

The first three plantations were from EEA INTA Bella Vista, Corrientes (Argentina); grapefruit ‘Paraná’ were 

produced in Paraguay. Values of pH were in the range of 3.41 to 4.15; acidity titratable higher than 1042mg/g 

tissue; total sugars between 71.65 to 99.70 mg glu/100mL (57% were sucrose) and ash between 0.279 and 

0.993%. Naringin levels rose from 1.76 to 7.61 mg/100 mL, neohesperidin from 1.07 to 0.20 mg/100 mL for 

‘Dalan dan’ (CT) and ‘Duncan’ respectively. Hesperidin was not detected in the grapefruits ‘Dalan dan’ (CC) 

and ‘Duncan’, but trace amounts were determined in the other 2 varieties. It was noted that the grapefruit 

‘Duncan’ has more than twice of the naringin content and lower neohesperidin and sucrose content than 

other fruits analyzed. No significant differences were found between parameters of fruits ‘Dalan dan’ and 

‘Paraná’. On the other hand, the results of sensory evaluation showed that the fruits of ´Dalan dan´ are 

sweeter and with a flavor similar to ´Parana´, while ´Duncan´ fruits have the higher acidity. 


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S17P11 

Evaluation of Lemon Selections for the Deserts of the United States 

Wright G.C. 1 , and Kahn T. 2 

1 University of Arizona (Univ of AZ), Yuma Agriculture Center, USA; and 2 University of California Riverside, Department of Botany and 

Plant Sciences, USA. gwright@ag.arizona.edu 

New lemon selections suitable for the US desert climate are needed to diversify production. Desert lemons 

occupy an early-season market niche and are a source of fruit for packinghouses located in the region and 

in cooler areas. This project was designed to evaluate 12 lemon selections under desert conditions. The 

objectives are to provide the lemon industry with information on tree growth, yield, packout, and fruit 

quality characteristics for selections. These include: ‘Allen Eureka’, ‘Variegated Pink-Fleshed Eureka’, ‘Corona 

Foothills’ (a bud sport of ‘Villafranca’), ‘Limoneira 8A’ Lisbon’, ‘Walker Lisbon’, ‘Femminello Santa Teresa’, 

‘Interdonato’, ‘Limonero Fino 49’, Limonero Fino 95’, ‘Messina’, ‘Seedless’ lemon and ‘Yen Ben’. ‘Corona 

Foothills’, ‘Limonero Fino 49’, ‘Walker Lisbon’ and ‘Femminello Santa Teresa’ have heretofore had the greatest 

yields, while ‘Messina’, and ‘Variegated Pink-Fleshed Eureka’ have had the least yield. ‘Yen Ben’ had adequate 

yields, but had later maturing fruit than most of the other selections. With regards to fruit packout, ‘Messina’ 

had the largest size, followed by ‘Corona Foothills’, ‘Interdonato’, ‘Limonero Fino 49’ and ‘Limonero Fino 

95’. ‘Variegated Pink-Fleshed Eureka’ and ‘Yen Ben’ had the smallest sized fruit. There was little effect of 

selection upon fruit exterior quality. ‘Variegated Pink Eureka’, ‘Yen Ben’, ‘Messina’ and ‘Seedless’ had the least 

number of seeds per fruit, while ‘Interdonato’ had the most, followed by ‘Walker Lisbon’, ‘Corona Foothills’, 

‘Femminello Santa Teresa’ and ‘Limonero Fino 49’. ‘Interdonato’, ‘Yen Ben’, ‘Messina’ and ‘Seedless’ had the 

smoothest peel, while ‘Variegated Pink Eureka’ had the roughest. There were significant differences between 

the selections as to % juice, juice pH, acidity levels and peel thickness. 

S17P12 

Selection and field evaluation of three new cultivars of lemon in the South-east of Spain 

Porras I., Pérez-Pérez J. G., García-Lidón A., Sánchez-Baños M., and Pérez-Tornero O. 

Murcian Institute of Agriculture and Food Research and Development (IMIDA), Department of Citriculture, Spain. 

ignacio.porras@carm.es 

South-east of Spain is the major exporter of lemon for fresh market, being ‘Fino’ the main group of lemon 

varieties with more than 80% of the total production. To continue leading the international lemon market it is 

necessary to incorporate new varieties which improve fruit quality and diversify supply. Three new selections 

of lemon have been evaluated in a citrus breeding program at IMIDA: ‘Finolate’, ‘Fino Callosa’, and ‘Garpo’, 

and were compared with ‘Fino 49’, the most widespread lemon variety in this region. These varieties were 

originated by spontaneous mutation. Morphological determination were carried out both in leaves and 

fruits, including leaf size and area, number stomata, petiole length, fruit weight, number of seeds and others. 

Fruit quality parameters from the three varieties were similar to ‘Fino 49’, except in rind colour of ‘Garpo’. 

‘Fino Callosa’ had the highest yield due to higher number of fruits per tree. ‘Finolate’ was classified as a late 

ripening cultivar and their fruits can be easily stored in tree. 

S17P13 

Preselection of promising triploid mandarin varieties in Corsica 

Bouffin J. 1 , Froelicher Y. 1 , Luro F. 2 , and Ollitrault P. 1 

1 Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), Bios / Agap, France; and 2 Institut 

National de la Recherche Agronomique (INRA), Gap, France. jean.bouffin@orange.fr 

The selection of seedless mandarin varieties adapted to the European market is one of the main objectives 

of the CIRAD breeding program. Triploid hybrid creation is the method selected to develop seedless varieties. 

More than one thousand triploid progenies are currently evaluated at the San Giuliano Research Station in 

Corsica. There were created by 2x X 2x hybridization exploiting spontaneous 2n gametes. The objective of a 

first set of crosses with clementine as female parent was to select clementine-like varieties, in order to extend 


the production period of this crop in Corsica. Seven hybrids were preselected at the end of the first level of 

evaluation according to the visual and organoleptic fruit characteristics, the period of production and the 

yield. There are currently under the second level of evaluation to analyse their agronomic behaviour. One 

of this hybrids is under D.U.S. examination for the grant of Community plant variety rights. The objective of 

a more recent second set of crosses is to develop late mandarin varieties. Several progenies, with different 

mandarins as female parent, present interesting fruit characteristics. One of them, with short juvenile period 

and very high yield, is preselected for the second stage of evaluation. 

S17P14 

Two new IVIA triploid hybrids of mandarin, ‘IVIA-592’ and ‘IVIA-599’ 

Cuenca J., Aleza P., Juárez J., Pina J.A., and Navarro L. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain. jjuarez@ivia.es 

In citrus there are two clearly differentiated markets: the fresh fruit and the processed juice. In the 

Mediterranean area, citrus fruits are primarily produced for the fresh fruit market and Spain is the principal 

producer of the area. Seedlessness is one of the most important characteristics for mandarin fresh fruit. 

Triploid hybrids allow implementing this trait in commercial varieties. In this work we described ‘IVIA-592’ 

and ‘IVIA-599’, two new triploid hybrids originated from the IVIA triploid breeding program that will be 

released to growers in 2013. IVIA-592 was obtained from an open pollinated ‘Fortune’ mandarin. Fruits reach 

optimum maturity at the beginning of January, although they can be harvested from December until the end 

of January. Fruits are easy-to-peel with a diameter between 55-60 mm and fruit rind is deep orange red in 

color. IVIA-599 was obtained from a cross between ‘Fortune’ and ‘Kara’ mandarins. Fruits reach optimum 

maturity at the beginning of February, although they can be harvested from January until second half of 

February. Fruits are easy-to-peel with a diameter between 60-70 mm and fruit rind is orange red in color. This 

variety has the same origin as ‘Safor’, a previously released triploid hybrid. The fruits of the two varieties are 

somewhat similar, but ‘IVIA-599’ matures one month earlier. With these two varieties it will be possible to 

supply similar fruits to the market from January to the end of March. 

S17P15 

Selection of new ‘Ponkan’ like mandarins 

Bastianel M., Cristofani-Yaly M., Schinor E.H., Simonetti L.M., Manente K.K.M., de Negri J.D., Azevedo F.A., and Machado 

M.A. 

Centro de Citricultura Sylvio Moreira, Instituto Agronômico, Brasil. mbastianel@centrodecitricultura.br 

Although the citriculture is one of the most important economic activities in Brazil, it is based on a small 

number of varieties. To increase the number of varieties/genotypes with potential for commercial growing, 

either for the industry or fresh market, has been one of the main objectives of citrus breeding programs. 

There are few available commercial varieties of mandarins being the ‘Rio’ and ‘Montenegrin’ (Citrus 

deliciosa), the most produced in the South and Northeast regions of the country, and ‘Ponkan’ (C. reticulata) 

and ‘Murcott’ tangor are the most produced in the Southeast region. ‘Ponkan’ mandarin is preferred by 

the local market, mainly for easy-peeling greatly appreciated by the consumer. However, besides having 

a restricted period of harvest, it is susceptible to Alternaria Brown Spot (Alternaria alternata) which has 

hindered its maintenance in the orchards. Aiming to offer a larger number of commercial varieties with 

different harvest periods, more than 200 accessions of mandarins present in the Germoplasm Bank, and 

more than 200 hybrids generated in the breeding program are being evaluated. We selected about 50 

mandarins accessions and two hybrids (‘Ponkan’ x ‘Murcott’) that have physical characteristics similar 

to ‘Ponkan’ fruits. These materials were evaluated for maturation curves and other characteristics of 

commercial interest (fruit size, skin color, number of seeds and disease resistance). Differences were 

observed among tested materials, as fruit characteristics and in vitro resistance to Alternaria. Promising 

materials will be established in regional trials for evaluation of production. 


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S17P16 

New tangors for Brazilian citriculture 

Schinor E.H., Pacheco C.A., Bastianel M., Azevedo F.A., and Cristofani-Yaly M. 

Centro APTA Citrus Sylvio Moreira/IAC, Brazil. evandro@centrodecitricultura.br 

Obtaining of hybrids is an important strategy for the improvement of citrus. Since 1997, the Centro de 

Citricultura Sylvio Moreira – Instituto Agronômico, has been conducting an extensive program of citrus 

breeding via hybridization, to explore sources of disease resistance. Among the hybrids obtained from crosses 

between ‘Murcot’t tangor (TM) and ‘Pera’ sweet orange (LP), two of them were visually selected as potential 

cultivars. The aim of this study was to characterize horticulturally these materials. The plants of the hybrid 

‘TMxLP 281’ are medium-sized, with high production. The fruits had early harvest season between April and 

June, the fruits are flattened and they have intense orange color of the skin and pulp, with average weight of 

145 g, 42.0% of juice content, º Brix of 12.4%, acidity of 1.02% and ratio of 12.1, indicating its potential for 

fresh fruit market. The plants of the hybrid ‘TMxLP 16’ are high, with good production. The ‘TMxLP 16’ showed 

fruit early ripening, with a harvest season between April and June, with fruits have a rounded shape, intense 

orange color of the skin and pulp, with average weight of 202 g, 56.9% of juice yield, 12.9% ºBrix, acidity 

1.06% and ratio of 12.2, with the potential for fresh market and juice industry. The analysis of acceptability 

showed 67 and 71% of fruit approval and 96 and 98% of intent to purchase by the analysts, for hybrids ‘TMxLP 

281’ and ‘TMxLP 16’, respectively. To the juice of the hybrid ‘TMxLP 16’ the acceptability and purchase intent 

were 83 and 94%, respectively. Financial support: FAPESP, CNPq, INCT-Citrus. 

S17P17 

Three new easy peeler varieties bred by the Agricultural Research Council released world wise. 

van Rensburg P.J. 1 , Sippel A.D. 2 , Combrink N.K. 2 , Maritz J.G.J. 2 , and Bijzet Z. 2 

1 LGS Exports (Sa), Po Box 12484, Stellenbosch, 7613, South Africa; and 2 Agricultural Research Council – Institute for Tropical and 

Subtropical Crops, Private Bag X11208, Nelspruit, 1200, South Africa (ARC/ ITSC), South Africa. pietvrensburg@worldonline.co.za 

A brief description of the ‘ARCCIT1614’, ‘ARCCIT1519’ and ‘Sonet’, bred by researchers at the Institute for 

Tropical and Subtropial Crops (ITSC) of the Agricultural Research Council (ARC), will be provided, as well 

as performance data on these varieties. Both the ‘ARCCIT1614’ and ‘ARCCIT1519’ are ‘Ellendale’ x ‘Robin’ 

hybrids made by hand pollinations in 1982 by Dr H de Lange. Seeds were irradiated prior to planting (0.1 kgy 

gama radiation) in an attempt to induce seedlessness. Both these varieties have high internal quality and are 

high yielding mid season easy peeler varieties, maturing in June in South Africa. The ‘Sonet’ originated from 

seed from an open pollinated ‘Miho Wase’ satsuma tree, growing adjacent to ‘Nova’, ‘Ellendale’ and ‘Novelty’ 

pollen sources. The seed was harvested in 1996 from the ‘Miho Wase’ satsuma fruit. The ‘Sonet’ is a high 

yielding easy peeler variety, maturing at the end of March in South Africa. The IP management of these three 

varieties has been licensed to LGS Exports (SA) of South Africa for the EU, USA, Morocco and most of South 

America. 

S17P18 

A new potential elite citrus hybrid 

Cheng C.F., Wei Z.X. 1 Hong L., Wu C.Q., and Qi J.R. 

Chongqing Academy of Agricultural Sciences (CAAS), Fruit Research Institute, China. chengchf@hotmail.com 

A new elite citrus type was generated which resulted from a hybrid progeny from crosses of ‘Licheng’ sweet 

orange and ‘Chandler’ red pummelo in 2004. The hybrid seedling was grafted on a three year old satsuma 

mandarin in the next year. In 2010, the grafted hybrid bloomed, and the tree had 49.5% flower branch with 

leaves, 50.5% without leaves, meanwhile it showed well fruit set. The smooth fruit, whose fruit shape index 

was 0.83, is aromatic, with a circular trace at the blossom end. The total soluble solid of the fruit was 14.0%, 

which contained 9.95% of total sugar. The content of vitamin C in fruit reached 46.45 mg/100 ml, and the 

total titrated acid was lower, only 0.79 g/100 mL, so TSS/TA ratio became higher and got to 17.6. Interestingly, 

only 1.2 monoembryonic seeds were found per fruit. So, this is a promising new citrus hybrid type. 


S17P19 

Acceptability of ‘Fremont’ mandarin in Brazil: a variety with agronomic performance and 

resistance to Alternaria Brown Spot. 

Pacheco C.A., Schinor E.H., Moretti M.R., Bastianel M., Machado M.A., and Azevedo F.A. 

Centro APTA Citros Sylvio Moreira/IAC, Brasil. camilla_andrade@yahoo.com.br 

Evaluated the pattern of consumption of mandarin and acceptability of a new variety of this group, the 

‘Fremont’ mandarin (Citrus clementina x C. reticulata), opposite the Brazilian population, represented by 

the inhabitants of Cordeirópolis, São Paulo state and region. Questionnaires were administered to a group of 

50 subjects to evaluate the frequency and the consumption habits such fruit as well as the acceptability of 

the new variety under study, taking into consideration age, sex and street addresses of the participants. The 

consumer acceptance test was conducted in a laboratory with untrained, where samples of juice and fruit 

were served in disposable cups and plates, respectively, at room temperature in the presence of drinking 

water to rinse the palate between tasting and another sample. A nine-point hedonic scale to evaluate the 

external and internal characteristics of the fruit and the juice, as well as a five-point hedonic scale to analyze 

consumer purchase intent were used. Such evaluations have found that only 8% of the panelists consume 

mandarins every day, while 40% of the panelists reported consuming fruit at least 1-3 times per month. On 

the issue of acceptance, samples processed (juice) and fresh (fruit) were 79% and 69% approval, respectively, 

showing good acceptance by the judges. However, purchase intent among consumers was excellent, and 84% 

of the tasters would buy the juice and 70% buy the fruit of ‘Fremont’ mandarin. 

S17P20 

Scion and rootstock combinations for ornamental citrus in containers 

Fadini M. 1 , Girardi E.A. 2 , Santos M.G. 2 , Gesteira A.S. 2 , Passos O.S. 2 , Souza F.V.D. 2 , and Soares Filho W.S. 2 

1 Universidade Federal do Recôncavo da Bahia (UFRB), Centro de Ciências Agrárias, Ambientais e Biológicas - CCAAB, Brasil; and 

2 Centro Nacional de Pesquisa de Mandioca e Fruticultura - Embrapa Mandioca e Fruticultura (CNPMF - Embrapa), Núcleo de Recursos 

Genéticos e Desenvolvimento de Variedades - NUGENE, Brasil. wsoares@cnpmf.embrapa.br 

The selection of ornamental citrus genotypes has been carried out in Cruz das Almas, Bahia, Brazil, by the 

Citrus Breeding Program of Embrapa Cassava & Fruits in order to introduce this activity. Herein, we report 

results from two experiments evaluating the performance of scion and rootstock combinations for ornamental 

purposes. In the first trial the hybrid ‘Rangpur’ lime x Microcitrus ‘Sydney Hybrid-004’ (‘LCR x MCSH-004’) was 

budded and cleft grafted onto ‘HTR-051’ and ‘HTR-010’ dwarfing rootstocks in containers for home gardens. 

In the second trial Severinia buxifolia, Triphasia trifolia, Fortunella japonica, ‘Variegated’ calamondin, Citrus 

amblycarpa, ‘Variegated Cara-Cara’ sweet orange and ‘LCR x MCSH-004’ were budded onto 12 rootstocks 

in containers for landscaping. Budding is recommended for ‘LCR x MCSH-004’ propagation, and initial plant 

growth and branching were higher on ‘HTR-051’. Budtake of T. trifolia was not successful on any rootstock. 

All scion varieties performed well in containers except to C. amblycarpa which was too vigorous. ‘Flying 

Dragon’ trifoliate orange and ‘HTR-051 ‘rootstocks led to lower canopies, with ‘San Diego’ citrandarin, ‘HTR- 

051’, ‘HTR-053’, ‘HTR-069’ and ‘TSKC x (LCR x TR)-059’ inducing higher flower and fruit set. The hybrid ‘LCR 

x MCSH-004’ showed high potential for ornamental use. An adequate scion and rootstock combination is 

critical for ornamental citrus cultivation in containers to improve size control and other traits such as budtake 

and flowering. 

S17P21 

Current situation of the Chilean citrus industry 

Castro M., Besoain X., Herrera V., and Cautin R. 

Pontificia Universidad Catolica De Valparaiso (Pucv), Facultad De Agronomia, Chile. mcastro@ucv.c 

Traditionally the Chilean citrus industry had been oriented to the local market; however, it has significantly 

changed to the fresh fruit export over the last years. The opening of the Japanese market for lemons and the 

opening of the US mandarin & orange market has had a mayor influence in this situation. The main citrus- 


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growing areas are from Coquimbo Region (29°SL) to O’Higgins Region (34.45° SL) where the dry summer 

and Mediterranean climate prevails. Presently 18,934 ha are planted in total, distributed in oranges (41.4%), 

lemons (37.5%), mandarins and clementines (19.1%), grapefruits (1.52%), limes (0.3%) and tangelos (0.2%). 

Regarding exports, a total 134.7 million dollars were exported, which included oranges (39.6%), lemons 

(27.2%), clementines (22%), mandarins (10.5%), and grapefruits (0.7%). Rootstocks have a strong influence 

on the variety grafted on citrus. The most used ones in the last four years are: ‘C-35’ (oranges, mandarins, 

grapefruit and lime), Citrus macrophylla (lemons and limes), ‘Rubidoux’ (oranges and grapefruits) and 

‘Carrizo’ (oranges, mandarins, grapefruit and limes). With regard to varieties, the most used in lemons are: 

‘Fino 49’, ‘Eureka’, and ‘Messina’; in oranges, ‘Fukumoto’, ‘Parent Washington’ and ‘Lane Late’; in mandarins, 

‘W. Murcott’, ‘Orogrande’ and ‘Clemenules’; and in grapefruit, ‘Star Ruby’. Over the last years, the Chilean 

industry has been interested in introducing protected varieties into the varieties offered. 

S17P22 

Influence of gamma irradiation on seedless citrus production: pollen germination and fruit quality 

Bermejo A., Pardo J., and Zaragoza S. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Citricultura y Producción Vegetal, España. bermejo_alm@gva.es 

Gamma irradiation is widely used to obtain seedless citrus fruits. Herein, different new clones obtained 

by bud irradiation of several seedy citrus cultivars grown in the Mediterranean climate were studied to 

assess seedlessness, pollen germination, fruit characteristics and quality attributes. Findings indicate that 

irradiation altered aspects other than seedlessness, such as pollen germination, and some of the clones 

presented different size, acidity and maturity index. Fruit quality and nutritional bio-components also were 

affected. Our results indicated high contents in natural antioxidants as vitamin C, carotenoids and phenolic 

compounds in these citrus varieties, and provide a qualitative and quantitative survey of the fruit taste and 

organoleptic quality. High-performance liquid chromatographic methods were used to identify and quantify 

of these bioactive compounds. These aspects are necessary for the consumer that demands the prevention 

of health problems through nutrition and certain fruit quality traits including fruit size, internal quality, good 

rind colour and easy peeling. All irradiated clones examined presented lower seed numbers and reduced 

pollen germination compared to the corresponding controls, and some of these clones, which ripen late in 

the season and whose fruit quality is maintained or improved, are in the process of registration. In conclusion, 

budwood irradiation is a suitable technique to improve cultivars, produce seedless cultivars, adjust ripening 

time or raise the content of health-promoting compounds. 

S17P23 

Identification of new volatile compounds in a citrus hybrid mandarinquat ‘Indio’ (Citrus japonica 

× Citrus reticulata) 

Delort E., Decorzant E., Casilli A., and Jaquier A. 

Firmenich SA, Analytical Innovation, Switzerland. estelle.delort@firmenich.com 

The volatile composition of mandarinquat peel extract was investigated for the first time. At first sight, 

GC/MS chromatograms appeared to be very complex, due to the probable addition of the traits of both 

parents. Consequently, many peaks could not be identified due to co-elutions. Further investigation based 

on more sophisticated processing procedure (deconvolution software) and advanced chromatographic 

techniques (two-dimension GC/MS) have been carried out. Compared to deconvolution software, the use 

of a two-dimension GC/MS allowed elucidating most of the co-elutions. Finally, our study showed that, 

even if the hybrid contained many of the compounds found in one or both parents, some compounds were 

lower-expressed; some others were even absent in the hybrid. Surprisingly, a few compounds, which have 

never been identified in any of the parents, were identified. The identification of new volatile compounds in 

hybrids may result from the interaction between the two genomes during hybridization, which may cause the 

activation of some genes by the other genome which are otherwise silent in the parent genome. 


S17P24 

Molecular characterization of ‘Tahiti’ lime selections by RAPD analysis 

Bremer Neto H. 1 , Mourão Filho F.A.A. 1 , Stuchi E.S. 2 , Soriano L. 3 , Miyata L. 1 , and Camargo L.E.A. 4 

1 Universidade de São Paulo (USP), Crop Science, Brazil; 2 Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA), Centro Nacional de 

Pesquisa de Mandioca e Fruticultura, Brazil; 3 Universidade de São Paulo (USP), Centro de Energia Nuclear na Agricultura, Brazil; and 

4 Universidade de São Paulo (USP), Plant Pathology and Nemathology, Brazil. horstbn@gmail.com 

Genetic diversity of ‘Tahiti’ lime is restricted, and in Brazil most of the commercial orchards are predominantly 

based on only two selections. New ‘Tahiti’ lime selections were obtained and their horticultural performance 

was evaluated in the State of São Paulo, Brazil, during seven years. Anatomical, physiological, and biometric 

analyses indicated differences between the ‘IAC 5’, ‘IAC 5-1’, ‘CNPMF/EECB’, ‘CNPMF 2000’ and ‘CNPMF 2001’ 

selections, especially between ‘CNPMF 2000’ and ‘CNPMF 2001’, which showed lower drought tolerance 

and reduced fruit yield. RAPD markers were used to evaluate the genetic similarity of these selections. PCR 

reactions with primers A7, A10 and AA7 resulted in 23 fragments of which only four were polymorphic. Specific 

markers were found for ‘CNPMF 2000’ which had the lowest genetic similarity related to the other ‘Tahiti’ 

lime selections. Morphological analyses corroborated this result, since plants of ‘CNPMF 2000’ selection had 

distinct morphological and anatomical characteristics, such as longer thorns and higher number of stomatas. 

S17P25 

A natural mutant cultivar ‘Zigui Shatian’ pummelo (Citrus grandis) showing self-sterility due to 

abnormal post-zygotic embryo development not self-incompatibility 

Chai L.J., Ge X.X., Biswas M.K., Xu Q., and Deng X.X. 


xxdeng@mail.hzau.edu.cn 

‘Shatian’ pummelo (Citrus grandis), a widespread citrus cultivar in China, was reported to be self-incompatible, 

and its pollen tube was believed to be arrested in style after self-pollination. Herein, we characterized one 

‘Shatian’ pummelo mutant, called ‘Zigui Shatian’ pummelo. It showed similar morphology (leaf shape, stoma 

size and density, pollen shape and size), the same development progress of female and stamen organ, and same 

DNA ploidy level as the common ‘Shatian’ pummelo. However, in contrast with the common ‘Shatian’ pummelo, 

pollen tubes of self-pollinated ‘Zigui Shatian’ could grow normally in the stigma, style and ovary, and finally enter 

into the embryo sac resulting in successful fertilization. Further histological analyses verified that post-zygotic 

development was abnormal which caused the seed abortion in self-pollination. Simple sequence repeats (SSR) 

analysis revealed that one of the 120 primers showed polymorphism; it indicated that ‘Zigui Shatian’ pummelo 

and ‘Shatian’ pummelo were different at DNA level. All these data suggested that there is another way to block 

the self-pollination in ‘Shatian’ pummelo, not only in the style. Our research provided valuable information and 

material for the future in-depth study self-incompatibility mechanism in pummelo and other citrus species. 

S17P26 

Relation between temperature and the colour coordinate “a” during the development of the 

external colour of lemon fruits 

Conesa A. 1 , Manera J. 2 , Brotons J. 3 , and Porras I. 4 

1 Miguel Hernandez University (UMH), Department of Vegetable Production and Microbiology, Spain; 2 Miguel Hernandez University 

(UMH), Department of Physics and Architecture of Computers, Spain; 3 Miguel Hernandez University (Department of Economic and 

Financial Studies), UMH, Spain; and 4 Murcian Institute of Agriculture and Food Research and Development (IMIDA), Department of 

Citriculture, Spain. agustin.conesa@umh.es 

This study describes the evolution of the colour coordinate “a” in the peel of the lemon varieties ‘Eureka 

Frost’, ‘Lisbon Frost’ and the clone ‘Fino 49’, all on Citrus macrophylla rootstock, to ascertain the influence 

of temperature on the same. The study covered six campaigns (2003/04 and 2005/06 to 2009/10) with 

measurements of the colour coordinate “a”, being made every week or fortnight. The results point to greater 

correlation between the colour coordinate “a” in peel and low temperatures than medium temperatures. 

The coordination between the colour coordinate “a” and low temperatures is greatest for the mean value 


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recorded during the previous 21 days. The correlation between the loss of greenness in lemon peel and 

temperature increases if the mean of the minimum temperatures is considered, rather than the average 

of the means. The negative values of the colour coordinate “a” decrease (decreased greenness of the peel) 

with temperatures below 15-17 ºC, increasing as the minimum temperatures fall until they reach zero. The 

colour coordinate “a” and the mean minimum temperature for the 21 days preceding the measurement 

provides excellent adjustments. The good values of R2 for the varieties ‘Eureka’, ‘Fino’ and ‘Lisbon’ show that 

the synthesis of the many carotenoids in the peel varies as a function of temperature. The model present a 

higher correlation considering not only temperatures but colour coordinate a in a previous observation. For 

this purpose we are going to use a fixed type model. 

S17P27 

Determination of the geographical origin of navel orange by near infrared spectroscopy 

Su X.S. 1 , Zhang X.Y. 2 , Jiao B.N. 2 , and Cao W.Q. 1 

1 College of Chemistry and Chemical Engineering, Southwest University, China; and 2 Citrus Research Institute, Chinese Academy of 

Agricultural Sciences/Citrus Research Institute, Southwest University, China. suxuesu@163.com 

The capacity to identify the geographical origins of navel orange samples obtained from Jiangxi, Chongqing 

and Hunan provinces, was studied by near infrared reflectance spectroscopy (NIRS). Three models of navel 

orange traceability were developed using the first derivative (9 points smoothing) of spectra at 1140-1170 

nm combined with Soft Independent Modeling of Class Analogy (SIMCA). The three models were considered 

optimized when principal components were 2. Under the 5% significance level, the identification rates 

of the three models for sample calibration was all 100%, and the rejection rates were 85.7%, 83.3% and 

100%, respectively; while the identification rates for sample validation were all 100%, and the rejection 

rates were 100%, 89.5% and 100%, respectively. Giving values 0, 1, -1 for Jiangxi, Chongqing and Hunan 

classes as category variable, partial least squares-discrimination analysis models(PLS-DA) were established to 

determine geographical origins of navel oranges. The best models were developed using raw spectra at 950- 

1650 nm when principal components were 13. The results showed that the correlation between the predicted 

category variable and the measured category variable was significant with high correlation coefficient (R2, 

0.973), low root mean square error of calibration (RMSEC, 0.109) and root mean square error of prediction 

(RMSEP, 0.159). The identification rates of PLS-DA model for calibration and validation samples were both 

100%. These results indicated that NIRS coupled with SIMCA and PLS-DA methods can be used for quickly and 

accurately discriminating geographical origin of navel orange samples. 

S17P28 

A new lemon genotype for ornamental use obtained by gamma irradiation 

Uzun A. 1 , Gulsen O. 1 , Kafa G. 2 , and Seday U. 2 

1 Erciyes University, Department of Horticulture, Turkey; and 2 Alata Horticultural Research Station, Genetics and Breeding, Turkey. 

aydinuzun@erciyes.edu.tr 

Some citrus species and cultivars with attractive appearance of fruits and leaves are used for ornamental 

purposes. Some of them have small fruit and plant size and mixed color of leaves or fruits. We report here a new 

lemon genotype with potential use for ornamental purposes. This genotype was obtained exposing budwood 

of the ‘Kutdiken’ lemon cultivar to gamma irradiation. This variety is widely grown in Turkey because of its high 

yield and good quality fruits. Fruits of the new genotype have attractive appearance with vertical brown lines 

and brown point heaps. Differences of fruit rind of this genotype have originated from mutation/mutations 

caused by gamma irradiation. This genotype has a good potential for ornamental use indoors or in gardens. 

S17P29 

New mandarin triploid hybrids Àya´ and `Hana´ selected in Morocco 

Handaji N. 1 , Benyahia H. 1 , Benaouda H. 1 , Arsalane N. 1 , and Srairi I. 2 

1 Institut National de la Recherche Agronomique (INRA), Morocco; and 2 Domaine Kabbage, Morocco. citrusinra@yahoo.fr 

Triploidy has played important role in development of new seedless mandarin cultivars for fresh fruit market 

and have received increasing attention for the consumers. Many series of diploid x diploid crosses were 


assessed. Fruits were collected when ripe. Small embryos isolated from undeveloped seeds were cultured on 

Murashige and Skoog culture media supplemented with 1mg/L of gibberillic acid. Triploid plantlets selected 

by flow cytometry were grafted onto `Troyer´ citrange at INRA domain with spacing 6 x 3 meters. Two triploid 

mandarins, Àya´ and `Hana´, were identified as the best triploid hybrids showing commercial interest. These 

clones were described and registered in the official catalogue as new mandarins cultivars. 

S17P30 

Mutation breeding for seedless cultivars in Argentina 

Garavello M. 1 , Anderson C. 1 , Prina A. 2 , and Martinez A. 2 

1 Instituto Nacional de Tecnologia Agropecuaria (INTA), Concordia, Entre Ríos, Argentina; and 2 instituto de Genética “Edwald A. Favret” 

(IGEAF - INTA), Castelar, Buenos Aires, Argentina. mgaravello79@gmail.com 

For many years the application of irradiation techniques on citrus buds has been used in producing lowseeded 

selections from existing high quality citrus cultivars. An irradiating program began in 2008 at 

Concordia Experiment Station using X-rays for the elimination of seeds in commercially important cultivars. 

The irradiations were carried out at the Institute of Genetics belonging to the National Agricultural Research 

Center of INTA in Castelar, BsAs. The first step was to adjust the dose and exposure time on material of 

different species of citrus. Doses of 2 and 4 kr on grapefruit hybrids, and doses of 2, 4, 6, 8 and 10 kr on 

`Bonelli´ lemon (Citrus limon), `Roble´ sweet orange (C. sinensis) and `Willow leaf´ mandarin (C. deliciosa) 

were used. The irradiated material was top-worked on sweet orange trees in a high density plot. The 

doses were 2 kr for mandarins, and 4 kr for lemons, grapefruits and oranges. There were two subsequent 

treatments on the varieties, one in November of 2008 and another in March of 2009. The selections 

obtained were: two of sweet orange (0-1 seed/fruit), two of lemon (2-3 seeds/fruit) and one of grapefruit 

(5 seeds/fruit). These selections were budded in a nursery to assess their stability, production and other 

characteristics of interest. 


S17

Session 18 

ROOTSTOCKS 

S18

S18O01 

Reflections on a career in citrus rootstock evaluation and commercialization 

Castle W.S. 

University of Florida, Institute of Food & Agricultural Sciences (UF/IFAS), Citrus Research and Education Center, U.S.A. 

bcastle@ufl.edu 

The author undertook a 35-year career involved in the development and evaluation of new citrus rootstocks 

and commercialization of the most promising candidates. It was apparent at the close of that journey 

that rootstocks remained critical to successful citriculture, but improvements were still needed. Insights 

were gained along the way about the process starting with creating new rootstocks and ending with their 

adoption by growers. Many of the traditional objectives in creating new rootstocks remain in place, but new 

objectives related to tree size and disease have emerged. Thus, the history of rootstock development, use 

and importance in relation to other fruit crops is considered along with a particular interest of the author: 

the social component of rootstock research and commercialization and its consequences regarding the time 

course of evaluation and adoption of new rootstocks. Eventually, new rootstocks are released and the next 

step is commercialization. Evaluation of research data and the grower selection process are the ultimate 

human experience in the realm of rootstocks. Thus, because choosing rootstocks is a human endeavor, it is 

influenced by many factors. Among the selection criteria is the expected use of a new rootstock. Lastly, our 

reliance in Florida on cooperative research is emphasized. 

S18O02 

Citrus rootstocks in Morocco: Present situation and future prospects 

El Guilli M. 1 , Belmahdi I. 2 and Zemzami M. 3 

1 Institut National de la Recherche Agronomique (INRA), Phytopathology, Morroco; 2 Office National de la Sécurité Sanitaire des 

Produits Alimentaires (ONSSA), Phytopathology, Morroco; and 3 Domaines Agricoles (DA), Virology, Morroco. mguilli@yahoo.com 

Until the last decade, the Moroccan citrus industry has relied exclusively on sour orange as a rootstock. 

However, rootstock trials were initiated in the 1960’s at the experimental farms of INRA. The major selection 

traits targeted at that time included yield and fruit quality, compatibility with clementine varieties and 

tolerance to Phytophthora Gummosis, salt and limestone soils. In spite of the outstanding results of some 

rootstocks revealed by these trials, sour orange continued to be the main rootstock of choice of citrus farmers. 

Not until year 2000, after a long and intense debate among citrus industry stockholders, was a real action 

initiated to diversify citrus rootstocks in new plantings. While sour orange remained in use, trifoliate hybrids 

(‘Carrizo’, ‘Troyer’, ‘C-35’), Citrus volkameriana, and Citrus macrophylla started to increase in percentage, 

especially in large nurseries. In 2008, during a sanitary survey in the Loukous region in the North of Morocco, 

CTV was detected at high incidence in many orchards. A big effort is actually being done to promote the use 

of CTV tolerant rootstocks. Figures of how each of these rootstocks has developed during the last 6 years are 

presented. A preliminary assessment of the impact of the rootstock shift on yield, quality and market reaction 

is discussed. 

S18O03 

Seven hybrid citrus rootstocks released by USDA: comparison of characteristics and use 

Bowman K.D. and Albrecht U. 

United States Department of Agriculture, Agricultural Research Service (USDA, ARS), United States Horticultural Research Laboratory, 

USA. kim.bowman@ars.usda.gov 

The USDA-ARS has supported a long-term citrus rootstock breeding program in Florida, and in the past two 

decades the Florida citrus industry has also provided strong financial support for USDA rootstock development. 

The result of this effort has been the development and release of seven hybrid citrus rootstocks that, to 

varying degrees, have achieved commercial success in Florida and in other citrus production areas around 

the world. During the 2010 propagation cycle, about 62 percent of all Florida nursery trees, or 1,855,798 

trees, were propagated on the seven USDA rootstocks in Florida. These rootstocks, ‘Carrizo’ citrange (Citrus 


S18

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sinensis × Poncirus trifoliata), ‘Swingle’ citrumelo (Citrus paradisi × P. trifoliata), ‘US-852’ (Citrus reticulata 

‘Changsha’ × P. trifoliata ‘English Large’), ‘US-812’ (C. reticulata ‘Sunki’ × P. trifoliata ‘Benecke’), ‘US-897’ (C. 

reticulata ‘Cleopatra’ × P. trifoliata ‘Flying Dragon’), ‘US-802’ (Citrus grandis ‘Siamese’ × P. trifoliata), and 

‘US-942’ (C. reticulata ‘Sunki’ × P. trifoliata ‘Flying Dragon’), each have some strong attributes that prompted 

their release and commercial interest, including outstanding performance in field trials with commercial scion 

cultivars. Although information about each rootstock was provided during release, in many cases only limited 

information was available comparing the seven rootstocks because they were developed in different eras 

or tested in different trial locations. In this study, we compare the nursery characteristics, susceptibilities to 

disease, and performance of the seven rootstocks under a range of different field conditions. Although all 

seven rootstocks induce good scion fruit productivity under some conditions, the large differences in effect 

on scion vigor and tolerance of biotic and abiotic stresses, result in each rootstock having a different ideal 

niche for commercial use. 

S18O04 

The evaluation of Chinese rootstock for tree growth, yield and quality of ‘Lane Late’ oranges 

grown in Australia 

Khurshid T. 1 , Sanderson G. 2 and Donovan N. 3 

1 Dareton Primary Industries Institute (DPII), New South Wales Department of Primary Industries, Australia; 2 Dareton Primary Industries 

Institute (DPII), New South Wales, Department of Primary Industries, Australia; and 3 Elizabeth McArthur Agricultural Institute (EMAI), 

Biosecurity Research, Australia. tahir.khurshid@dpi.nsw.gov.au 

This paper reports on the short term performance of a range of new rootstocks imported from China. 

The experimental program was conducted at the Dareton Primary Industries Institute, New South Wales 

Department of Primary Industries beginning in 1997. A detailed data is presented from a ‘Lane Late’ trial 

which was propagated on to a range of rootstock treatments including Citrus reticulata, Poncirus trifoliata, 

P. trifoliata hybrid, Citrus junos, Citrus erythrosa, Citrus aurantium hybrid, P. trifoliata (‘Tri22’ Australian 

strain), Citrus sinensis and (C. sinensis x P. trifoliata). The Australian standard ‘Tri22’ was used for comparison 

purposes. This trial was established in October 1999 to evaluate the horticultural performance of new 

rootstocks established from single-node cuttings with a ‘Lane Late’ scion. Six years of data (2002-2007) 

were collected on tree growth, fruit yield and quality to identify superior rootstocks for the next phase of 

semi commercial plantings. Chinese P. trifoliata type, ‘Houpi’ and ‘Zao Yang’ resulted in higher cumulative 

yields of 127 kg/tree and 115 kg/tree, respectively compared to 81 kg/tree for the control (‘Tri22’), and 

yield efficiencies of 2.4 and 3.2 kg/cm2, respectively compared to 2.5 kg/cm2 were produced. ‘Houpi’ had a 

large trunk circumference of 26 cm compared to ‘Tri22’ while ‘Zao Yang’ had a similar trunk circumference 

of 20 cm compared to ‘Tri22’. Data on tree growth, fruit quality and fruit size distribution are presented for 

all other rootstocks. 

S18O05 

Dwarfing rootstocks for ‘Valencia’ sweet orange 

Ramos Y.C. 1 , Stuchi E.S. 2 , Girardi E.A. 2 , Leão H.C. 3 , Gesteira A.S. 2 , Passos O.S. 2 and Soares Filho W.S. 2 

1 Escola Superior de Agricultura “Luiz de Queiroz” - Universidade de São Paulo (ESALQ - USP), Departamento de Produção Vegetal, 

Brasil; 2 Centro Nacional de Pesquisa de Mandioca e Fruticultura - Embrapa Mandioca e Fruticultura (CNPMF - Embrapa), Núcleo de 

Recursos Genéticos e Desenvolvimento de Variedades - NUGENE, Brasil; and 3 Fischer S/A - Comércio, Indústria e Agricultura (Grupo 

Fischer), Departamento Técnico da Citrosuco, Brasil. wsoares@cnpmf.embrapa.br 

The Brazilian and other citrus industries will likely require, among other technologies, the use of rootstocks 

that are suitable for higher planting densities with high production efficiency of high quality fruits and tolerant 

to abiotic and biotic stresses. Considering this approach, hybrid rootstocks have been obtained by the Citrus 

Breeding Program of Embrapa Cassava & Fruits, in Cruz das Almas, Bahia State, Brazil. One experiment 

evaluating the first three commercial crops of ‘Valencia’ sweet orange budded on several genotypes in 

Colômbia, São Paulo State, Brazil, indicated that the hybrids ‘TSKC (‘Sunki’ mandarin) x [LCR (‘Rangpur’ lime) 

x TR (trifoliate orange)] – 059’, ‘TSKC x CTSW (‘Swingle’ citrumelo) – 033’, ‘TSKC x CTSW – 041’, ‘LCR x TR – 

001’, ‘HTR (trifoliate hybrid) – 051’, ‘HTR – 053’ and ‘HTR – 069’ allowed planting densities higher than those 


attained with the use of the traditional rootstocks ‘Rangpur’ lime and ‘Sunki’ mandarin. They also induced 

higher production efficiency of fruits with higher or equivalent quality in comparison to fruits on ‘Rangpur’ 

lime, which is the usual rootstock in Brazil. Additionally, ‘TSKC x (LCR x TR) – 059’ and ‘LCR x TR – 001’ induced 

higher tolerance to drought, with results similar to ‘Rangpur’ lime, and the first hybrid also anticipated fruit 

bearing of the scion variety. In spite of not being dwarfing rootstocks, the hybrids ‘TSKC x CTTR (‘Troyer’ 

citrange) – 002’ and ‘TSKC x CTSW – 028’, as well as ‘Rangpur’ lime selection ‘CNPMF-03’, ‘Sunki Tropical’ 

mandarin and ‘Indio’ and ‘San Diego’ citrandarins performed well. 

S18O06 

The development of improved tetraploid citrus rootstocks to facilitate advanced production 

systems and sustainable citriculture in Florida 

Grosser J.W., Barthe G.A., Gmitter Jr. F.G., and Castle W.S. 

University of Florida, Citrus Research and Education Center (CREC), Horticultural Sciences, USA. jgrosser@ufl.edu 

The 10 billion dollar/year Florida citrus industry is now under siege by an insect vectored bacterial disease 

Citrus Greening, also known as Huanglongbing (HLB). Genetic resistance to HLB is not present in commercial 

scion or rootstock cultivars. A possible mid-term solution to this problem is to shorten the grove rotation 

and time to profitability by adapting open hydroponics systems (OHS) or other similar evolving production 

systems to Florida conditions. Such systems that feature high density plantings being developed will require 

improved tree-size controlling rootstocks that bear early and produce good yields of fruit with juice of high 

quality. We have been exploring somatic hybridization of complementary diploid rootstocks via protoplast 

fusion to generate allotetraploid rootstock candidates, and more recently we have been conducting rootstock 

breeding at the tetraploid level by crossing superior somatic hybrids. Preliminary testing suggests that 

tetraploid rootstock candidates from both of these sources have potential to facilitate the success of new 

production systems, as selected allotetraploid rootstocks generally exhibit good soil adaptation, disease 

resistance, nursery and young tree growth, and also a strong tendency to reduce tree size. A major rootstock 

trial is underway that features high planting densities and a production system that mimics the principles of 

OHS, with a goal of identifying superior rootstocks for use in advanced production systems. This trial includes 

selected somatic hybrids, tetrazygs, diploid hybrids and controls, with trees being grown using slow release 

fertilizer and daily short-duration microjet irrigation. Yield and fruit quality data from this and other trials 

will be presented, as there are significant rootstock affects on both parameters. The best somatic hybrid 

and ‘tetrazyg’ rootstocks will be highlighted. The unexpected reduced impact of HLB in the trial will also be 

discussed. 

S18O07 

Citrus macrophylla rootstock improves the performance of ‘Mexican’ lime trees on citrus 

interstocks in calcareous soils 

Medina-Urrutia V.M. 1 , Robles-González M.M. 2 , Virgen-Calleros G. 1 and Manzanilla-Ramírez M.A. 2 

1 Universidad de Guadalajara (CUCBA-UDG), Centro Universitario de Ciencias Biologicas y Agropecuarias, Mexico; and 2 Instituto 

Nacional de Investigaciones Forestales Agricolas y Pecuarias (INIFAP-Colima), CIRPAC, Mexico. vmmedinau@gmail.com 

Most lime orchards are planted using Mexican lime (ML) (Citrus aurantifolia) trees budded on ‘Alemow’ (ALE) 

(Citrus macrophylla) vigorous rootstocks on calcareous soils in México. Citrus tree size can be reduced using 

Poncirus trifoliata and hybrid rootstocks which are not well adapted to calcareous soils. The effect of different 

citrus rootstocks used as interstocks on growth and yield of ML trees was determined during 10 years in 

Tecomán, Col., México. The purpose was to reduce the tree size of ML/ALE combinations to increase the 

plant densities on calcareous soils to mitigate the impact of HLB disease. Twenty one different interstocks 

between ML scion and ALE rootstock and the control (ML/ALE) were evaluated. Sixteen trifoliate genotypes, 

four mandarins types and Severinia buxifolia (SB) were included as interstocks. ML trees on FDT and ‘Hiryu’ 

trifoliate orange interstocks reduced by over 40% the canopy volume compared to the control. Also FDT and 

‘Hiryu’ showed the greatest interstock tree trunk, followed by many citranges. Average ML yield during the 

first five years ranged from 80.8-117.1 kg/tree/year. SB and ‘Morton’ citrange as interstocks obtained the 


S18

S18 

lower and higher ML yields/tree, respectively. Most interstocks produced similar yields to the control ML/ALE 

(108.1 kg/tree/year). ‘Hiryu’ and FDT interstocks that significantly reduced the tree size of limes produced 

100 kg/tree. In the second period of five years, ML yields ranged from 96.8- to 184.7 kg/tree/year. ‘Hiryu’ and 

‘C-35’ citrange interstocks produced the lower and higher yields, respectively. Seven trifoliate yield higher 

than control. Estimated tree density using dwarfing combinations was around 600 trees/ha, which produced 

more than 60 t/ha-1 under HLB-free conditions. 

S18O08 

Performance of ‘Valencia Late’ orange on 14 rootstocks in the Gharb region in Morocco 

Benyahia H. 1 , Benazzouz A. 1 , Talha A. 1 , Beniken L. 1 , Omari F.E. 1 , Handaji N. 1 , Jacquemend E. 2 and Srairi I. 3 

1National Institut for Agricultural Research (INRA), Department of Plant Breeding and Phytogenetic Ressources Conservation, 

Laboratory of Citrus Breeding, Kenitra, Morocco, BP 257; 2Agricultural Research Station of San Giuliano (INRA/CIRAD), Corse, F-20230, 

France; and 3Domaines Abbès El Kabbage (DAK), Agadir, Morocco. hamidbenyahia2002@yahoo.fr 

Citrus is a major and valuable crop in Morocco and it is by far one of the most important export crops. 

The most important orange variety grown commercially in Morocco is the ‘Valencia Late Nucellar’ and, as 

for all other citrus cultivars, the main rootstock used is sour orange. This study was conducted in order to 

evaluate the effect of various rootstocks on yield, yield efficiency, tree size and fruit quality of the ‘Valencia 

Late’ orange in the Gharb region in Morocco and to identify rootstocks that may replace sour orange. Total 

cumulative yield over 5 years of production was the highest on ‘Swingle’ citrumelo and Poncirus trifoliata 

‘B6Z13’. In terms of productivity, ‘Swingle’ citrumelo, Citrus volkameriana, the hybrid ‘Sunki’ mandarin x P. 

trifoliata, Citrus macrophylla and the hybrid ‘Sunki’ mandarin x P. trifoliata 16 seem far rootstocks promoters. 

This study revealed that some rootstocks have made a significant improvement in the rate of juice of ‘Valencia 

Late’ variety. These rootstocks are: C. volkameriana, ‘PT 6 B CZ 24’, ‘PT 6 B CZ 13’, ‘Cleopatra’ mandarin 

x ‘Carrizo’ citrange, ‘Swingle’ citrumelo and citrumelo ‘1452’. In terms of acidity and Brix, this study has 

identified rootstocks that have made a significant improvement in both parameters of fruit quality. These 

rootstocks are ‘Carrizo’ citrange, ‘Sunki’ mandarin, P. trifoliata, Citrumelo ‘1452’, ‘Swingle’ citrumelo and 

‘Sunki’ mandarin x P. trifoliata 16. 

S18O09 

Results from a three years field trial planted at Concordia, Argentina using transgenic rootstocks 

potentially resistant to Citrus Tristeza 

Anderson C. 1 , Plata M.I. 1 , Garavello M. 1 , Costa N1 and Peña L. 2 

1Estacion Experimental Agropecuaria Concordia, Instituto Nacional de Tecnología Agropecuaria (EEA INTA), Concordia, Entre Rios, 

Argentina; and 2Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, 

Valencia, España. anderson.citrus@gmail.com 

Citrus Tristeza Virus (CTV) causes one of the most devastating diseases of citrus worldwide. It induces the 

death of sweet orange, mandarin, lime and grapefruit trees budded on sour orange, which has determined 

its replacement by other CTV-tolerant rootstocks. The availability of a CTV-resistant rootstock with the sour 

orange attributes of productivity, fruit quality and tolerance to abiotic stresses would be a major benefit 

to the citrus industry worldwide. The objective of the field trial was to evaluate the response to CTV of 10 

sour orange (Citrus aurantium) transgenic lines carrying CTV-derived sequences. They were obtained in the 

laboratories of IVIA, Spain and planted at INTA Experiment Station in Concordia, Argentina, where CTV is 

endemic and efficiently transmitted by the Brown Citrus Aphid (Toxoptera citricida). Trees were obtained by 

budding rooted cuttings of transgenic sour orange lines with non-transgenic and virus-free ‘Valencia Late’ 

sweet orange (Citrus sinensis). ‘Valencia’ trees budded on tolerant rootstocks as well as non-transgenic sour 

orange were planted as controls. Trees were planted in a complete randomized design with two trees per plot 

and 5 replications. Every six months imprints were taken to determine the progress of CTV infection in each 

tree. Three and half years after planting, 47.3 % of the trees are CTV infected, showing stunting growth and 

yellowing of foliage. 


S18O10 

‘Forner-Alcaide 5’: a citrus rootstock released in Spain 

Forner-Giner M.A., and Forner J.B. 

Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Citricultura y Producción Vegetal, Spain. forner_maginer@gva.es 

‘Forner-Alcaide 5’ is an interspecific hybrid rootstock between ‘Cleopatra’ mandarin (Citrus reshni) and Poncirus 

trifoliata obtained in a program for breeding citrus rootstocks at the Instituto Valenciano de Investigaciones 

Agrarias (IVIA). This rootstock is commercial in Spain since 2005. ‘Forner-Alcaide 5’ is resistant to Citrus Tristeza 

Virus (CTV) and citrus nematode (Tylenchulus semipenetrans). ‘Carrizo’ citrange (Citrus sinensis x P. trifoliata), 

the most used rootstock in Spain, frequently shows iron chlorosis and salinity problems. ‘Forner-Alcaide 5’ 

shows a high resistance to salinity, similar to ‘Cleopatra’ mandarin and it is more tolerant to iron chlorosis 

than ‘Carrizo’ citrange. The behavior of this rootstock in water stress and flooding screening tests is good, as 

well as its Phytophthora spp. tolerance. Agricultural performance of ‘Forner-Alcaide 5’ has been evaluated 

with navel oranges, satsumas and clementines, compared to the traditional rootstocks used in Spain. This 

rootstock always shows a higher productivity than ‘Carrizo’ citrange, a good fruit size and fruit quality. 

S18P01 

Rootstocks affect fruit yield and some fruit quality traits of ‘Star Ruby’ grapefruit in Adana, Turkey 

Yeşiloğlu T., İncesu M., Yılmaz B., Çimen B. and Tuzcu Ö. 

University of Cukurova (CU), Horticulture, Turkey. turgutyesiloglu@gmail.com 

In this study, the effects of local sour orange (Citrus aurantium), ‘Taiwanica’ (Citrus taiwanica), ‘Yuzu’ (Citrus 

junos), ‘Troyer’ and ‘Carrizo’ citranges (Citrus sinensis x Poncirus trifoliata), ‘Cleopatra’ mandarin (Citrus reshni) 

and also Citrus ampullacea, ‘Kinkôji’ (Citrus obovoidea) and ‘Sanbôkan’ (Citrus sulcata) on some pomological 

characteristics of ‘Star Ruby’ grapefruit were evaluated under Adana ecological conditions. Fruit yield (kg), fruit 

weight (g), height (mm), diameter (mm), index, juice quantity (%), rind thickness (mm), total soluble solids (TSS, 

%), total acid content (TA, %), TSS/TA ratio, fruit peel and juice colour (hueo) were evaluated. Yield was the highest 

on C. sulcata followed by that on ‘Cleopatra’ and sour orange. The largest fruit size was obtained from the trees 

on ‘Carrizo’ citrange, followed by ‘Troyer’. The thickest fruit rind was showed by fruits from the trees on ‘Carrizo’ 

and the thinnest on ‘Taiwanica’ and sour orange. However, trees on the other rootstocks produced similar rind 

thickness and did not showed significant difference from each other. There were significant differences between 

rootstocks as regards TSS/TA ratio. It was the highest for fruits from the trees on ‘Carrizo’. According to the hueo 

data, red colour in both peel and juice were the highest in the fruits on ‘Carrizo’ and ‘Troyer’ citranges. 

S18P02 

Rootstock effects on photosynthetic performance of young ‘Valencia’ orange trees 

Yeşiloğlu T., Çimen B., İncesu M. and Yılmaz B. 

University of Cukurova (CU), Department of Horticulture, Turkey. bcimen@cu.edu.tr 

Iron deficiency is a major problem for many fruit crops grown on calcareous soils. Citrus production in the 

Mediterranean region is often made in high pH calcareous soils, therefore, nutrient imbalances regarding iron 

deficiency often occur. In this study, ‘Valencia’ orange budded on five rootstocks (‘Carrizo’ citrange, ‘Swingle’ 

citrumelo, ‘Rangpur’ lime, ‘Antalya Cleopatra’ mandarin, ‘Tuzcu 31-31’ sour orange) were evaluated in terms 

of their photosynthetic performances in calcareous soil. Thus leaf chlorophyll concentration, chlorophyll 

fluorescence parameters in light-adapted (FT: Continuous fluorescence yield, QY: FV’ /FM’: Photosystem 

II quantum yield) and leaf gas exchange parameters (photosynthesis rate, transpiration rate, stomatal 

conductance and leaf water use efficiency) were measured. Scions which were grown on the rootstocks 

‘Rangpur’ lime and ‘Antalya Cleopatra’ mandarin had the highest chlorophyll contents while ‘Swingle’ 

citrumelo had the lowest. However, leaves of scions did not differ in terms of transpiration rate, leaves of 

shoots on ‘Swingle’ citrumelo displayed a significant reduction in photosynthetic rate, stomatal conductance 

and quantum yield of photosystem II. The highest photosynthetic rate and leaf water use efficiency were 

obtained from the leaves of scions grafted on sour orange. 


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S18P03 

Effect of the rootstock on some agronomic traits of ‘Nules’ and ‘Nour’ clementines in the Souss 

valey in south Morocco 

Benyahia H. 1 , Benazzouz A. 1 , Beniken L. 1 , Handaji N. 1 , Kabbaj T. 2 , Essajid A. 2 , Chahidi B. 2 , Jacquemend E. 3 and Srairi I. 1 

1 National Institut for Agricultural Research (INRA), Department of Plant Breeding and Phytogenetic Ressources Conservation, 

Laboratory of Citrus Breeding, Kenitra, Morocco; 2 Domaines Abbès El Kabbage (DAK), Agadir, Morocco; and 3 Agricultural Research 

Station of San Giuliano (INRA/CIRAD), Corse, France. hamidbenyahia2002@yahoo.fr 

In Morocco, citrus cover about 105,000 ha. Clementine, a species concentrated in Souss and Moulouya 

regions, accounts for 24% of citrus. Sour orange, the dominant rootstock in Morocco citrus groves, is 

sensitive to Tristeza disease. Recently, many interesting rootstocks have been introduced from abroad. An 

experimental trial was initiated in 1997 in the Souss Valley in South Morocco. It was aimed at evaluating 

vegetative development, production and fruit quality of two clementine varieties (‘Nour and ‘Nules) grafted 

on 22 different rootstocks. The trial was set on and soil composed of sand/loam with a moderate pH (8,5) 

at a planting density of 6x3m. Plants grafted on Citrus macrophylla and Citrus volkameriana had the highest 

canopy volume and exceeded significantly all the other combinations. These two rootstocks had also the 

best yields over a period of 10 years. ‘Troyer’ citrange ranked third for ‘Nules’ and an even lower production 

for ‘Nour’. For ‘Nour’, the second and third productive rootstock was ‘Cleopatra’ mandarin. Some hybrids 

of Poncirus trifoliata improved significantly fruit quality (% of juice, Brix and acidity) in comparison to sour 

orange. Fruits size was more improved by C. macrophylla and C. volkameriana especially for ‘Nour’. The most 

efficient production was obtained with a dwarfing hybrid (‘Sunki’ mandarin x P. trifoliata), C. volkameriana for 

‘Nules’, followed by ‘Nour’. We conclude that there are some advantages conferred by some new rootstocks 

in comparison to sour orange. They permit a high productivity, earliness in fruit set and improved fruit quality. 

S18P04 

Behavior of ‘Navelina ISA 315’ on 15 rootstocks in Metaponto area, Basilicata, Italy 

Mennone C. 1 , Ippolito A. 2 and Reforgiato Recupero G. 3 

1 Azienda Agricola Sperimentale Dimostrativa Pantanello, Italy; 2 Università degli Studi “Aldo Moro”, Bari, Dipartimento di Scienze del 

Suolo, della Pianta e degli Alimenti, Italy; and 3 CRA- Centro di Ricerca per l’Agrumicoltura e le Colture Mediterranee (CRA-ACM), Italy. 

giuseppe.reforgiato@entecra.it 

With the epidemic spread of Citrus Tristeza Virus (CTV) in Italian citriculture, sour orange, the most used 

rootstock, has been almost completely abandoned, because of its susceptibility to the disease. Even if a 

number of alternative rootstocks tolerant to CTV are available, their adaptability in specific conditions needs 

to be tested. At the Pantanello research Station, Metaponto, Basilicata Region, Italy, Citrus tachibana, trifoliate 

oranges ‘Yamaguchi’, ‘Argentina’, ‘Roubidoux’ and ‘Flying Dragon’, tangelo ‘Orlando’, sour oranges ‘S. Marina’ 

and ‘Platania’, Citrus macrophylla, ‘Ichang’ pummelo, citranges ‘Troyer’ and ‘Carrizo’, citrumelo ‘Swingle’, 

‘Siamelo’, and ‘Poorman’s’ orange have been planted using as scion ‘Navelina ISA 315’ sweet orange. Since 

1983 fruit production and quality were evaluated. In each combination ten trees were arranged in a complete 

randomized block design. Among the tested rootstocks, interesting results in relation to fruit production 

and quality were obtained with citranges, showing a vigour comparable to sour orange. Some plants grafted 

on ‘Swingle’, showing a severe symptom of iron chlorosis, died. Trifoliate orange selections, mainly ‘Flying 

Dragon’, induced a reduced canopy and low production. 

S18P05 

Influence of rootstock on the characteristics of clementine in the plain of Sibari, Italy 

Russo G. 1 , Reforgiato Recupero G. 1 , Recupero S. 1 , Pietro Paolo D. 1 , Di Leo A. 2 and Filippelli S. 2 

1 Centro di Ricerca per l’Agrumicoltura e le Colture Mediterranee (CRA-ACM), Italy; and 2 Centro Sperimentale Dimostrativo (ARSSA), 

Mirto Crosia Italy. giuseppe.russo@entecra.it 

In May of 2002, a trial was started in the plain of Sibari, a typical area for clementine in Italy, using four 

varieties of clementines grafted on five rootstocks (sour orange, ‘Carrizo’ citrange, ‘Swingle’ citrumelo, 

‘Flying Dragon’ trifoliate orange and ‘Alemow’). The clementine varieties were two early maturing 


selections (‘Caffin’ and ‘Spinoso VCR’), a medium (‘SRA 63’) and a late (‘Rubinio VCR’). The trial was 

conducted in a sandy soil with pH 8.26 (Total lime 6%, active lime 1.6 %). The planting distance was 5x4 m 

using a randomized complete-block design. The four selections of clementine on ‘Alemow’ showed over 

the years 2006-2011 the highest cumulative yield, followed by ‘Carrizo’ and ‘Swingle’. Sour orange induced 

a reduction of 50% on cumulative production than ‘Carrizo’. The most productive variety was clementine 

‘SRA 63’ followed by ‘Spinoso’. In terms of qualitative characteristics, ‘Alemow’ induced a reduction of 

total soluble solids concentration, and ‘Flying Dragon’ induced the highest content. Based on the induced 

production characteristics and tolerance to tristeza, ‘Carrizo’ and ‘Swingle’ are confirmed as subjects able 

to replace the sour orange. Even if clementine ‘SRA 63’ was the most productive variety, is problematic 

the evaluation of a variety within the clementines, without taking into account the ripening period, for the 

enormous influence of this factor on crop profitability. 

S18P06 

Is there a relationship between ferric-chelate reductase activity in roots of Poncirus trifoliata and 

leaf chlorophyll contents? 

Correia P.J., Lopes D., Duarte A., Gama F., Saavedra T. and Pestana M. 

Institute of Mediterranean Agricultural and Environmental Sciences - University of Algarve (ICAAM/UAlg), Faculty of Sciences and 

Technology, Portugal. aduarte@ualg.pt 

Poncirus trifoliata is a citrus rootstock very sensitive to Fe deficiency which is very common in crops grown in 

calcareous soils due to the detrimental effect of bicarbonate ion. Higher plants have distinct behaviors when 

faced with bicarbonate-induced Fe chlorosis, and several mechanisms may be activated under Fe shortage. 

The aim of this study was to investigate the activity of ferric-chelate reductase (FC-R), a key enzyme in Fe 

uptake, and to establish relationships with leaf chlorophyll. Plants were grown in nutrient solutions without 

Fe (0 µM Fe), with 1 µM Fe, with 120 µM Fe and with 120 µM Fe plus CaCO3 (1 g L-1). Total leaf chlorophyll 

in young and mature leaves was determined using a calibration model based on a relationship between SPAD 

readings and concentration of chlorophyll (r2=0.95; P

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S18P08 

Agronomic performance of ‘Nules’ clementine and ‘Navelate’ orange on citrus rootstocks ‘F-A 5’, 

‘F-A 13’ and ‘F-A 418’ in Northeastern Spain 

Fibla J.M. 1 , Pastor J. 1 , Martinez-Ferrer M.T. 1 , Campos Rivela J.M. 1 , Forner-Giner M.A. 2 and Forner J.B. 2 

1 Institut de Recerca i Tecnologia Agroalimentàries (IRTA), Fruit Production, Spain; and 2 Instituto Valenciano de Investigaciones Agrarias 

(IVIA), Centro de Citricultura y Producción Vegetal, Spain. teresa.martinez@irta.cat 

The agronomic performance in northeastern Spain (Tarragona) of three new rootstocks reducing canopy 

volume ‘Forner Alcaide 5’ (F-A 5), ‘Forner Alcaide 13’ (F-A 13) [hybrids of ‘Cleopatra’ mandarin (Citrus reshni) 

and Poncirus trifoliata] and ‘Forner Alcaide 418’ (F-A 418) [hybrid of ‘Troyer’ citrange (Citrus sinensis X P. 

trifoliata) x common mandarin (Citrus deliciosa] was studied. In May 2000, trees were planted including 

‘Carrizo’ citrange as a standard. Rootstocks were grafted with ‘Nules’ clementine (Citrus clementina) and 

‘Navelate’ orange (C. sinensis). Vegetative growth, yield and fruit quality was determined from 2004 until 

2012. In ‘Nules’ clementine, F-A 5 rootstock did not reduce tree growth. Yield and canopy volume were 

higher than with the other rootstocks. Trees on F-A 13 had a similar growth and yield than ‘Carrizo’ citrange, 

and F-A 418 induced a dwarfing effect and both growth and yield were lower than in the other rootstocks. 

F-A 5 showed a ‘Navelate’ growth and yield performance similar to ‘Carrizo’ citrange, and both were higher 

than the other two rootstocks tested. ‘Navelate’ trees on F-A 13 showed an intermediate response between 

F-A 5 and F-A 418. The latter induced a significant reduction in size and deficient vegetation. At harvest, no 

significant differences on fruit quality were found between rootstocks. However in trees on ‘Carrizo’ citrange 

rootstocks, a delay in the peel-colour index was found respect to F-A 5. 

S18P09 

New rootstocks for the high density plantings in citrus 

Bordas M. 1 , Torrents J. 1 and Forner-Giner M.A. 2 

1 Agromillora Research S.L. El Rebato s/n. 08739 Subirats (Barcelona)-Spain; and 2 Instituto Valenciano de Investigaciones Agrarias 

(IVIA), Centro de Citricultura y Producción Vegetal, Spain. mbordas@agromillora.com 

The general trend in fruit crops is the use of dwarfing/semi-dwarfing rootstocks to control vigour, allowing 

higher planting densities, enabling earlier production and increasing productivity per unit land area. The future 

development of the citrus industry is betting on the incorporation of dwarfing rootstocks, which offer alternative 

systems of production. In 2006, Agromillora and IVIA began a cooperative program with the aim to reduce size 

and to find suitable candidates for higher density system plantings. All the rootstocks included in this program 

are monoembryonic or seedless. Thus, micropropagation allows new options to produce new rootstocks that 

are difficult or impossible to propagate by traditional techniques, and to make plants available quickly. 35 hybrids 

between different parental species are being evaluated. We are testing for the tolerance/resistance to CTV, iron 

chlorosis, salinity, water stress and flooding. As a result of this research and preliminary field results, we selected 

4 dwarfing/ semidwarfing rootstocks, three hybrids ‘Cleopatra’ mandarin x Poncirus trifoliata (‘CIVAC03013’, 

‘CIVAC03014’, ‘CIVAC030119’) and one hybrid ‘King’ mandarin x P. trifoliata (‘CIVAC050122’), all tolerant to 

CTV. ‘CIVAC03014’ stands out for its high resistance to salinity and water stress tolerance; ‘CIVAC050122’ for 

resistance to iron chlorosis. These materials are being micropropagated for the establishment of experimental 

plots. It is intended to test their adaptation to a higher density production system and determine the most 

appropriate management for total mechanization using commercial scion varieties for the citrus industry. 

S18P10 

Performance of ‘Nules’ clementine grafted on twelve rootstocks in ANECOOP 

del Pino A. 1 , Martínez M. 1 and Forner-Giner M.A. 2 

1 ANECOOP, Spain; and 2 Instituto Valenciano de Investigaciones Agrarias (IVIA), Departamento de Citricultura y Producción Vegetal, 

Spain. adelpino@anecoop.com 

The aim of this trial was to study the performance of ‘Clemenules’ mandarin (Citrus clementina) on twelve 

rootstocks: ‘Carrizo’ and ‘C-35’ citranges [Citrus sinensis x Poncirus trifoliata], ‘Cleopatra’ mandarin (Citrus 


eshni), Citrus volkameriana, Citrus macrophylla, ‘Swingle’ citrumelo [Citrus paradisi x P. trifoliata], and six 

new hybrids obtained at the Instituto Valenciano de Investigaciones Agrarias (IVIA): ‘Forner-Alcaide 5’, ‘Forner- 

Alcaide 13’, ‘Forner-Alcaide 41’ and ‘Forner-Alcaide 31’ are hybrids of ‘Cleopatra’ mandarin and P. trifoliata, 

‘Forner-Alcaide V17’ is a hybrid of C. volkameriana and P. trifoliata, and ‘Forner-Alcaide 2324’ is a hybrid of 

‘Troyer’ citrange and ‘Cleopatra’ mandarin. The plot is located in the Experimental Field of ANECOOP, the 

“Masia del Doctor”, sited ten km north of Valencia (Spain). The trial was planted in 2004 and yield has been 

weighed during the first five harvests. In the first yield recorded, ‘Forner-Alcaide 5’ was the rootstock which 

produced more (80% higher than ‘Carrizo’ citrange), and after five years, it has the highest cumulative yield 

of all the rootstocks tested. ‘Carrizo’, ‘Forner-Alcaide V17’ and ‘Forner-Alcaide 13’ showed a high productivity 

and ‘C-35’, ‘Cleopatra’ mandarin, ‘Swingle’ citrumelo and C. volkameriana had the lowest. Fruit quality was 

analysed in the last two harvests. Rootstock significantly affected fruit quality variables. ‘Forner-Alcaide 5’, 

‘Former-Alcaide 13’ and ‘Forner-Alcaide V17’ would appear to induce higher fruit size, juice content and fruit 

quality. 

S18P11 

Influence of rootstock hydraulic conductance in the response to water stress and its relationship 

to aquaporin expression in citrus 

Rodríguez-Gamir J. 1 , Ancillo G. 2 , Bordas M. 3 , Primo-Millo E. 1 and Forner-Giner M.A. 1 

1 Instituto Valenciano e Investigaciones Agrarias (IVIA), Centro de Citricultura y Producción Vegetal, Spain; 2 Instituto Valenciano e 

Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; and 3 Agromillora Research S.L, Spain. 

forner_margin@gva.es 

Recent climate projections by the International Panel for Climate Change (IPCC, 2007) predict that water 

scarcity will increase in the near future in many regions of the globe. Therefore, climate change poses an 

acute problem to the citrus crops because the sector is expected to maintain its yield/quality standards under 

more adverse climate conditions. Agronomic strategies such as the use of new rootstocks better adapted 

to dryer conditions are needed. Plant water relations may be affected by drought stress and root hydraulic 

conductance determines the ability of the rootstock to supply water and nutrients to the plant. This ability 

could be the main factor influencing plant tolerance to abiotic stresses. Aquaporins are involved in regulating 

root hydraulic conductance by mediating water flow through the cell membranes. Hypothesizing that 

aquaporins could play a role in citrus response to water stress, responsiveness of photosynthetic parameters 

and water balance to moderate water stress in different citrus rootstocks was evaluated. The plant materials 

used were the rootstocks Poncirus trifoliata, ‘Cleopatra’ mandarin (Citrus reshni and ‘030115’ (a hybrid of 

the two former rootstocks), all grafted with the citrus variety ‘Valencia Late’ (Citrus sinensis). Results showed 

that down-regulation at transcriptional level results in decreased root hydraulic conductance. This facilitates 

water maintenance in the cells and adequate levels of leaf water potential and photosynthesis in plants under 

water stress. Thus, the decrease of aquaporin expression could be a water stress tolerance mechanism in 

citrus. 

S18P12 

Micropropagation for evaluation of new citrus somatic hybrid rootstocks 

Bordas M. 1 , Torrents J. 1 and Navarro L. 2 

1 Agromillora Research, S.L, Spain; and 2 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y 

Biotecnología, Spain. mbordas@agromillora.com 

In citrus, virtually no rootstocks have tolerance or resistance to all the main biotic and abiotic stresses present 

in a given growing area of the world and at the same time induce high yields and fruit quality. Although 

several breeding programs are currently active to produce such rootstocks, propagation and evaluation of new 

hybrids continues to be an important component of the development process. The development of somatic 

hybridization by protoplast fusion in citrus has helped reach improvement goals that seemed unattainable 

by conventional methods. It is possible to add the genomes of the parents in the hybrids without or with 

very little recombination. At IVIA, a collection of somatic hybrids between ‘Carrizo’ citrange (Citrus sinensis 

x Poncirus trifoliata) and Citrus macrophylla and Citrus taiwanica have been obtained. These hybrids are 


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potentially very interesting for the Spanish citrus industry, but they are juvenile and do not produce seeds for 

conventional evaluation. In 2011, a collaboration between Agromillora and IVIA began for the multiplication 

and evaluation of new citrus somatic hybrid rootstocks. We will present the development of a protocol for 

the micropropagation of three allotetraploid somatic hybrids. We have determined the conditions for the in 

vitro introduction and the establishment of lines in the laboratory, obtaining highly efficient multiplications 

rates. The environmental conditions in the greenhouse for the successful acclimatization and growth have 

also been set. Finally, we have accomplished the large-scale adaptation for efficient commercial propagation. 

This is allowing a very quick process to start evaluation at large scale. 

S18P13 

Performance of ‘Forner-Alcaide 5’ and ‘Forner-Alcaide 517’ with ‘Loretina’ clementine. 

Molina-Nadal M.D. 1 , De Miguel A. 1 , Valero J.L. 1 , Ripoll F. 2 and Forner-Giner M.A. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Citricultura y Producción Vegetal, Spain; and 2 Cooperativa de 

Algemesí (COOPAL), Spain. molina_marnad@gva.es 

The influence of two citrus rootstocks, ‘Forner-Alcaide 5’ [Citrus reshni x Poncirus trifoliata] and ‘Forner- 

Alcaide 517’ [‘King’ mandarin (Citrus nobilis) x P. trifoliata] a semidwarfing rootstock, on growth, yield and 

fruit quality on ‘Loretina’ clementine (Citrus clementina) has been analysed. Trees were grown in a plot in 

Algemesi, near Valencia (Spain) and had been planted in 2000. Yield was weighed during five harvest, and 

fruit quality and tree size determined in 2011. Tree size of plants grafted on ‘Forner-Alcaide 517’ grow 40% 

less than ‘Forner-Alcaide 5’. Yield efficiency (kg/m3) in 2011 between rootstocks has no differences. Fruit size 

is smaller in ‘Forner-Alcaide 517’ than in ‘Forner-Alcaide 5’, but sugar content and acidity is higher in ‘Forner- 

Alcaide 517’ than in ‘Forner-Alcaide 5’. 

S18P14 

Performance of three rootstocks with ‘Clemenrubi’ and ‘Orogros’ clementines cultivated under 

screen. 

Molina-Nadal M.D 1 , de Miguel A. 1 , Bonafé C. 1 , Valero J.L. 1 , Ripoll F. 2 and Forner-Giner M.A. 3 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Servivio de transferencia de tecnología de Carcaixent, Spain; 2 Cooperativa 

Agraria de Algemesí (COOPAL), Spain; and 3 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Citricultura y Producción 

Vegetal, Spain. molina_marnad@gva.es 

In a screenhouse trial planted in 2004 and grafted in 2005 with two precocious clementines, ‘Clemenrubi’ and 

‘Orogros’ (Citrus clementina), three citrus rootstocks: ‘Carrizo’ and ‘C-35’ citranges [Citrus sinensis x Poncirus 

trifoliata] and ‘Forner-Alcaide 5’ [Citrus reshni x P. trifoliata] were evaluated in an orchard near Valencia. Yield, 

fruit size and fruit quality were evaluated for the last four years. Tree size has been evaluated the last year. 

In the last yield, ‘Forner-Alcaide 5’ and ‘C-35’ showed no differences, but ‘C-35’ is the rootstock that showed 

higher cumulative yield of the three rootstocks involved in the experiment. Citrange ‘Carrizo’ presented 

smaller fruit size, juice content in both varieties, than the other rootstocks, but higher peel thickness. Fruits 

on ‘Forner-Alcaide 5’ had higher maturity index. All the plants in the experiment showed multiple shooting 

alterations in the truck of the variety. For this reason, 30% of fruits of ‘Clemenrubi’ and 7% on ‘Orogros’ 

grafted on ‘Carrizo’ citrange had dry juice sacs. ‘Forner-Alcaide 5’ presented only 1% of fruits affected and 

‘C-35’ 3%, in both cultivars. 

S18P15 

Rootstock influence on the incidence of fruit splitting in navel oranges 

Mesejo C., Reig C., Martínez-Fuentes A. and Agustí M. 

Instituto Agroforestal Mediterraneo. Universitat Politècnica de València (IAM-UPV), España. carmeco@upv.es 

This study aimed to determine the influence of four rootstocks, ‘Cleopatra’ mandarin (Citrus reshni), ‘Carrizo’ 

and ‘C-35’ citranges [Citrus sinensis X Poncirus trifoliata], and ‘FA-5’ [C. reshni X P. trifoliata], on the incidence 

of fruit splitting in ‘Chislett’ and ‘Lane-late‘ navel oranges (C. sinensis). ‘Carrizo’ and ‘C-35’ citranges showed 


higher proportion of split fruits (15%) than ‘Cleopatra’ mandarin and ‘FA-5’ (5%). On the other hand, ‘Chislett’ 

orange showed higher proportion of split fruits (10%) than ‘Lane-late’ orange (< 2%). Peel resistance to 

puncturing was not significantly modified by the rootstock. However, fruits from trees budded onto ‘Carrizo’ 

and ‘C-35’ citranges presented a thinner peel. On the other hand, cryo-scanning electron microscopy (SEM) 

of fruit peduncles showed that average area of xylem vessel were larger in fruits from trees budded onto 

‘Carrizo’ and ‘C-35’ citranges. 

S18P16 

Rootstocks for ‘Lane Late’ orange in Valencia 

del Pino A. 1 , Martínez M. 1 and Forner-Giner M.A. 2 

1 ANECOOP, Spain; and 2 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Citricultura y Producción Vegetal, Spain. 

adelpino@anecoop.com 

The performance of ‘Lane Late’ orange on twelve rootstocks has been evaluated: ‘Carrizo’ and ‘C-35’ 

citranges [Citrus sinensis x Poncirus trifoliata], ‘Cleopatra’ mandarin (Citrus reshni), Citrus volkameriana, 

Citrus macrophylla, ‘Swingle’ citrumelo [Citrus paradisi x P. trifoliata], and six new hybrids obtained at 

the Instituto Valenciano de Investigaciones Agrarias (IVIA): ‘Forner-Alcaide 5’, ‘Forner-Alcaide 13’, ‘Forner- 

Alcaide 41’ and ‘Forner-Alcaide 31’ which are hybrids of ‘Cleopatra’ mandarin and P. trifoliata, ‘Forner- 

Alcaide V17’ that is a hybrid of C. volkameriana and P. trifoliata and ‘Forner-Alcaide 2324’ that is a hybrid of 

‘Troyer’ citrange and ‘Cleopatra’ mandarin. The plot is located in the Experimental Field of ANECOOP, the 

“Masia del Doctor”, sited ten km north of Valencia (Spain) and planted in 2005. Five first yields have been 

determined and fruit quality has been analysed. Regarding to the yield, C. volkameriana is the rootstock 

that showed higher cumulative yield, followed by ‘Forner-Alcaide 5’, ‘Forner-Alcaide 13’ and ‘Carrizo’ 

citrange. The lowest yield was in ‘Lane Late’ orange grafted in ‘Forner-Alcaide V17’ and ‘Forner-Alcaide 

2324’. Differences in fruit quality have been found. 

S18P17 

Citrus rootstock trials on calcareous soils in California 

Roose M. L., Kupper R.S. and Federici C.T. 

University of California (UCR), Botany and Plant Sciences, Riverside, CA 9252 U.S.A. mikeal.roose@ucr.edu 

Calcareous soils are challenging for citrus production because relatively few rootstocks are well-adapted to 

such soils and also tolerant to Citrus Tristeza Virus and common soil pathogens. Many rootstocks derive 

disease resistance from trifoliate orange which is very susceptible to iron chlorosis and poor growth on 

calcareous soils. We report results of four rootstock trials on calcareous soils in California that were planted in 

1997 and 2001 with 26 to 32 experimental and standard rootstocks budded with navel orange, ‘Moro’ blood 

orange, and ‘Lisbon’ lemon. Data on tree size, health, and chlorosis were collected several times from 1997 

to 2011. Tree survival varied among sites and rootstocks but was nearly 100% for ‘Carrizo’, a fairly susceptible 

standard rootstock. Trees on trifoliate orange had moderate or high chlorosis and poor growth at all sites. 

Rootstocks with low chlorosis overall included ‘ASRT’ (‘African shaddock’ x ’Rubidoux’ trifoliate), ‘Bitters 

(C22)’, and several unreleased hybrids. At some sites, tree size was not correlated to chlorosis suggesting that 

other factors limited tree performance. 

S18P18 

Potential of ‘Tahiti’ acid lime and ‘Flame’ grapefruit in the Brazilian semiarid 

Bastos D.C. 1 , Passos O.S. 2 , Nascimento F.S.S. 1 and Nascimento S.S. 1 

1 Embrapa Semiarido (Embrapa CPATSA), Fruticultura - Fitotecnia, Brasisl; and 2 Embrapa Mandioca e Fruticultura Tropical (Embrapa 

CNPMF), Fruticultura - Fitotecnia, Brasil. debora@cpatsa.embrapa.br 

The citrus industry of the Brazilian notheastern region is concentrated mainly in the states of Bahia and 

Sergipe, accounting for 10% of the national citrus production. This region has peculiar characteristics 


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favorable for the citrus industry expansion. The climate is very hot and semiarid. The rainfall is less than 

600 mm and the average annual temperature is 26.2º C, relative humidity of 67% and solar radiation 

around 3,000h/year, constituting a comparative advantage with regard to biomass production and crops, 

especially fruits such as acid lime, lemon and grapefruit, supplemented by water via irrigation. This 

work was planned in order to evaluate the behavior of acid lime ‘Tahiti’ and ‘Flame’ grapefruit grafted 

on different rootstocks in the semiarid northeast. The experiments were conducted at the Experimental 

Station of Embrapa Semiarid in Juazeiro, Bahia, with ‘Tahiti’ and ‘Flame’ scions on twenty rootstocks 

mostly hybrids of Poncirus trifoliata. The rootstocks ‘Cleopatra mandarin x ‘Swingle trifoliate-288’, ‘Rusk’ 

citrange, ‘English trifoliate x Sunki mandarin-26 and 256’, ‘Cleopatra mandarin x Swingle trifoliate-294’, 

‘Swingle trifoliate x Sunki mandarin-314’ proved to be most promising rootstocks for ‘Flame’ and ‘Rusk’ 

citrange, ‘Volkameriana’ lemon, citrange ‘C35’, ‘English trifoliate x Sunki mandarin-264 and 256’, citrange 

‘Troyer’ and ‘Swingle trifoliate x Sunki mandarin-314’ for ‘Tahiti’, both in production and productivity 

under semiarid conditions. 

S18P19 

Selection of new citrandarins for citrus rootstocks 

Cristofani-Yaly M. 1 , Schinor E.H. 1 , Bastianel M. 1 , Nascimento A.L. 1 , Stuchi E.S. 2 and Machado M.A. 1 

1Centro de Citricultura, Instituto Agronômico (IAC), Brazil; and 2Embrapa Mandioca e Fruticultura and Estação Experimental de 

Citricultura de Bebedouro (Embrapa and EECB), Brazil. mariangela@centrodecitricultura.br 

In the 1990s, the Centro de Citricultura Sylvio Moreira / IAC launched a wide program of genetic breeding 

of citrus rootstocks through controlled crosses. From the hybridizations using several rootstocks varieties, 

we selected to evaluate 73 citrandarins (hybrids from ‘Sunki’ mandarin x Poncirus trifoliata ‘Rubidoux’). The 

hybrids were grafted with ‘Pera’ sweet orange and the trials were established in two regions of the São 

Paulo State. The experimental design was a randomized complete-block with three replications and one plant 

per plot without irrigation. Our results, in 5-yr-old plants, showed that the citrandarins influenced various 

horticultural traits of the scion as harvest season, yield, juice quality, and drought tolerance. The ºBrix ranged 

from 8 to 17, the canopy volume ranged from 3.51 to 11.30 m3 and the yield efficiency varied from 3.47 

to 18.94 kg/m3. Graft incompability with ‘Pera’ sweet orange was observed in six hybrids among the 73 

evaluated. Among the tested hybrids, 19 induced dwarfing into the scion variety. Financial support: FAPESP, 

CNPq, INCT-Citrus. 

S18P20 

Initial production of ‘Valencia’ sweet orange on 40 rootstocks in Northern São Paulo State, Brazil. 

Fadel A.L. 1 , Mourão Filho F.A.A. 1 , Stuchi E.S. 2 and Ramos Y.C. 1 

1Universidade de São Paulo (USP), Departamento de Produção Vegetal, Brazil; and 2Empresa Brasileira de Pesquisa Agropecuária 

(EMBRAPA), Estação Experimental de Citricultura de Bebedouro, Brazil. afadel@usp.br 

Due to increasing demand for diversification of rootstocks in Brazilian citrus industry, a research work was 

installed in March 2007 to evaluate 40 different rootstocks for ‘Valencia’ sweet orange (Citrus sinensis), in 

the Northern region of São Paulo State, Brazil. The experiment has a randomized block design with three 

replications and five plants per plot. The data regarding accumulated fruit production in 2010 and 2011 were 

submitted to variance analysis and the means were compared by Scott-Knott test (P

S18P21 

Crop production of ‘Okitsu’ satsuma mandarin on nine rootstocks in Southern Brazil 

Tazima Z.H. 1 , Neves C.S.V.J. 2 , Yada I.F.U. 3 and Leite Junior R.P. 4 

1 Instituto Agronômico do Paraná (IAPAR), Ecofisiologia, Brazil; 2 Universidade Estadual de Londrina (UEL), Agronomia, Brazil; 3 Instituto 

Agronômico do Paraná (IAPAR), Biometria, Brazil; and 4 Instituto Agronômico do Paraná (IAPAR), Proteção de Plantas, Brazil. 

zuleide@iapar.br 

This study reports the performance of ‘Okitsu’ satsuma mandarin (Citrus unshiu) trees grafted on nine 

different rootstocks and evaluated for nine harvests, in Southern Brazil. The field plot was established in the 

Experimental Station of Instituto Agronômico do Paraná (IAPAR), located in the municipality of Londrina, 

State of Paraná, Brazil, and planted in July 2000. The experimental design was randomized blocks with nine 

treatments, six replications, and two trees per plot. Trees on ‘Swingle’ citrumelo had the highest yield in all 

the nine years of evaluation. In contrast, trees on ‘Volkamer’ lemon had the lowest yield in seven of nine 

years of harvest. ‘Swingle’ rootstock induced both, the highest cumulative yield (1.568.7 kg/tree) and the 

highest average yield per tree. According to the relative yield, ‘Swingle’ citrumelo induced a production index 

of 58% higher than trees on ‘Rangpur’ lime, the most important citrus rootstock in Brazil. Furthermore, trees 

on ‘Rangpur’ lime had a performance similar to the ones on Trifoliate orange, in regard to crop production. 

In relation to yield efficiency, the trees on ‘Swingle’ were similar to the ones on Trifoliate orange, ‘C-13’, and 

‘Rangpur’ lime. No alternate bearing was observed for the ‘Okitsu’ satsuma mandarin trees in any of the nine 

different rootstocks studied. The highest yield efficiency was presented by trees on Trifoliate orange. Financial 

support: Instituto Agronômico do Paraná and Fundação Araucária 

S18P22 

Effect of rootstock on yield of ‘Okitsu’ satsuma mandarin on sandy soils in Southern Brazil 

Tazima Z.H. 1 , Neves, C.S.V.J. 2 , Yada I.F.U. 3 , Stenzel N.M.C. 4 and Leite Junior R.P. 5 

1 Instituto Agronômico do Paraná (IAPAR), Ecofisiologia, Brazil; 2 Universidade Estadual de Londrina (UEL), Agronomia, Brazil; 

3 Instituto Agronômico do Paraná (IAPAR), Biometria, Brazil; 4 Instituto Agronômico do Paraná (IAPAR), Fitotecnia, Brazil; and 5 Instituto 

Agronômico do Paraná (IAPAR), Proteção de plantas, Brazil. nstenzel@iapar.br 

Trees of ‘Okitsu’ satsuma mandarin grafted on nine different rootstocks were evaluated for eight harvests, 

in Southern Brazil. The field plot was established on Oxisol (Typic Haplorthox) at the Experimental Station of 

the Instituto Agronômico do Paraná (IAPAR), located in the Paranavaí municipality, State of Paraná, Brazil, 

in January 2001. The experimental design was randomized blocks with nine treatments, three replications, 

and two trees per plot. In regard to annual crop production, no statistical differences between treatments 

were observed in five of the eight years of harvest. The highest cumulative fruit yield and average yield per 

trees of ‘Okitsu’ satsuma mandarin were determined for the trees on ‘Volkamer’ lemon, ‘Rangpur’ lime, 

‘Caipira DAC’ sweet orange, ‘Cleopatra’ mandarin and ‘Carrizo’ citrange, while trees on ‘Sunki’ mandarin, ‘C 

13’ citrange, ‘Swingle’ citrumelo and trifoliate orange showed the lowest yield. Trees on ‘Volkamer’ lemon 

presented similar relative yield to the ones on ‘Rangpur’ lime, the main rootstock used in Brazil. Financial 

support: Instituto Agronômico do Paraná and Fundação Araucária. 

S18P23 

Scion rooting and its discriminance in ‘Shiranuhi’ mandarin hybrid in plastic film house in Korea 

Moon Y.E. 1 , Kang S.B. 2 , Kim Y.H. 2 and Han S.G. 2 

1 Agricultural Research Center for Climate Change, NIHHS, RDA, Republic of Korea; and 2 Citrus Research Station, NIHHS, RDA, Republic 

of Korea. yimoon@korea.kr 

Citrus is usually propagated by grafting onto rootstock. In Korea, as trifoliate orange (Poncirus trifoliata) 

has dwarf and strong cold hardness, it is widely used as the rootstock of satsuma mandarin. ‘Shiranuhi’ 

[(Citrus unshiu × Citrus sinensis) × Citrus reticulata)], a kind of citrus, also, generally grafted onto trifoliate 

orange, and most of farmers have recognized that ‘Shiranuhi’ root is trifoliate orange naturally. Meanwhile, 

reduction of flowering in ‘Shiranuhi’ orchards has been issued among farmers and researchers over the 

past few years, and they guessed that it was occurred by severe prunning, oversupply of fertilization, 


S18

S18 

overfruiting and temperature during growth periods. However, few researchers strongly assumed that it 

was caused by scion rooting of ‘Shiranuhi’. So, this study was carried out to find out relationships between 

reduction of flower and scion rooting, discriminance methods and the ecology of scion root of ‘Shiranuhi’ 

in Korea. From our results, when we conducted the DNA analysis, fourteen trees in less bloomed twenty 

trees was proved as tree with the scion rooting of ‘Shiranuhi’ and this results was firstly identified in Korea. 

Scion root of ‘Shiranuhi’ is tended to be 30% thicker and more vigorous in root growth than in the case 

of trifoliate orange. Scion root of ‘Shiranuhi’ was usually observed in a deeply planted tree, and xylem of 

‘Shiranuhi’ root indicated more white color than a case of trifoliata orange. ‘Shiranuhi’ tree by scion rooting 

was more vigorous but less flowering than trees grafted onto trifoliata orange. When we used F2/R15, F4/ 

R15 and F5/R15 primer for discriminance of ‘Shiranuhi’ root and trifoliate root, it was possible for us to 

discriminate scion roots of ‘Shiranuhi’. 

S18P24 

Effects of scion root on flowering, fruit quality and yield of ‘Shiranuhi’ mandarin hybrid in plastic 

film house in Korea 

Moon Y.E 1 , Kang S.B. 2 , Han S.G. 2 , Ko S.W. 2 , Chae C.W. 2 , Lee D.H. 3 and Choi Y.H. 2 

1 Agricultural Research Center for Climate Change, National Institute of Horticultural & Herbal Science. R.D.A., Korea, Republic of KR; 

2 Citrus Research Station, National Institute of Horticultural & Herbal Science. R.D.A., Korea, Republic of, KR; and 3 Planning Coordination 

Division, National Institute of Horticultural & Herbal Science. R.D.A., Korea, Republic of, KR. yimoon@korea.kr 

Most of citrus is usually propagated by grafting, and trifoliate orange (Poncirus trifoliata) is widely used as 

rootstock of satsuma mandarin since it has dwarf and cold hardness in Korea. ‘Shiranuhi’ mandarin [(Citrus 

unshiu × Citrus sinensis) × Citrus reticulata)] mainly needs trifoliate orange (P. trifoliata) as its rootstock. 

However, recently, scion root was observed in ‘Shiranuhi’ mandarin trees grafted onto the trifoliate orange. 

This study was carried out to find out effects of outbreak of scion root on the fruit quality, flowering and 

yield of ‘Shiranuhi’ mandarin in Korea. For the experiment, we selected three farmers who have outbreak 

of scion root in their ‘Shiranuhi’ mandarin orchards and surveyed the difference of growth and fruit quality 

of ‘Shiranuhi’ mandarin between scion root and rootstock root (trifoliate orange root). In our experiment, 

fruit size and weight of scion root of ‘Shiranuhi’ mandarin were smaller than rootstock root. Flesh ratio, 

also, showed decrease in scion root of ‘Shiranuhi’. Moreover, flowering was severely decreased in scion 

root trees than normal trees. Among survey of 174 ‘Shiranuhi’ mandarin trees, 160 trees were proved to be 

scion root, and they had less flowering. Yields of scion root (18.2 kg) decreased 30% compared to rootstock 

root (25.9 kg). However, there was no difference on the TSS, acidity and soluble solid-acid ratio between 

scion root tree and rootstock root tree. From the results, we concluded that scion root had negative 

influence on flowering, fruit size and the yields of ‘Shrinanuhi’ mandarin. Therefore, we suggest finding 

a solution to improve flowering, fruit size and fruit quality in ‘Shiranuhi’ mandarin which has outbreak of 

scion root. 

S18P25 

Evaluation on drought resistance traits of citrus rootstock seedlings based on multivariate statistics 

Xu X.B., Yang Y.L., Gu Q.Q., Huang C.H. and Qu X.Y. 

College of Agronomy,Jiangxi Agricultural University (JAU), P.R.China. xiaobiaoxu@hotmail.com 

The drought resistance of nine citrus rootstocks was comprehensively evaluated by determining the 

physiological indexes such as relative water content (RWC), the activity of superoxide dismutase (SOD), 

catalase (CAT), peroxidase (POD), malondialdehyde (MDA), proline (Pro) and soluble sugar content (SSC) 

under artificial controlling water condition by taking the seedlings of nine citrus rootstocks from the local 

citrus rootstock resources of Jiangxi province in China, named ‘Sanhu Red’ tangerine (Citrus reticulata), 

‘Choupi’ mandarin (Citrus aurantium), ‘Sanhu’ hybrid mandarin (C. reticulata × C. aurantium), ‘Chongyi’ wild 

tangerine (C. reticulata), ‘Citrumelo’ (Citrus grandis × Poncirus trifoliata), ‘Trifoliate orange’ (P. trifoliata), 

‘Goutou’ orange (C. aurantium), ‘Carrizo’ citrange (Citrus sinensis x P. trifoliata), ‘Sour’ pummelo (C. grandis) 

as tested materials through the analysis of principal components and subordinate function values. The results 


were found that the order of drought resistance was as follow: ‘Sanhu Red’ tangerine > ‘Goutou’ orange 

> ‘Carrizo’ citrange > ‘Choupi’ mandarin > ‘Trifoliate’ orange > ‘Citrumelo’ > ‘Chongyi’ mandarin > ‘Sanhu’ 

hybrid mandarin > ‘Sour’ pummelo. Furthermore, the ‘Sanhu Red’ tangerine is the local citrus variety of 

Jiangxi province and it has stronger drought resistance among the nine citrus rootstocks, which could provide 

a solid basis for exploiting rootstock resources of drought resistance. The result of the study could provide 

theoretical foundation for germplasm improving and reference for reasonable development of germplasm 

resource in citrus rootstocks. 

S18P26 

Performance of three sweet orange varieties grafted on different rootstocks 

Yan S.T. 1 , Cheng C.Z. 2 , Ma Y.Y. 2 , Wang X. 2 and Zhong G.Y. 3 

1Citrus Research Institute, Southwest University, China; 2Southwest University, College of Horticulture and Landscape Architecture, 

China; and 3Fruit Tree Research Institute, Guangdong Academy of Agricultural Sciences, China. shutangyan@sina.com 

The performance of three sweet orange (Citrus sinensis) varieties ‘Hamlin’, ‘Tongshui 72-1 Jincheng’ and 

‘Troivita’, were studied on 11 rootstock varieties ‘Rangpur’ lime (Citrus limonia) (RL), ‘Volkamer’ lemon 

(Citrus volkameriana) (VL), ‘Carrizo’ citrange (C. sinensis × Poncirus trifoliata) (CC), ‘Smooth Flat Seville’ 

(Citrus aurantium hybrid) (SFS), ‘Goutoucheng’ Sour Orange (C. aurantium) (GSO), ‘Sunchusha’ tangerine 

(Citrus reticulata) (ST), ‘Rich 16-6’ trifoliate orange (P. trifoliata) (R16-6), ‘Rubidoux’ trifoliate (P. trifoliata) 

(RT), ‘Pomeroy’ trifoliate (P. trifoliata) (PT), citrange (C. sinensis ‘Ruby’ × P. trifoliata) (C-35), and ‘Cleopatra’ 

mandarin (C. reticulata) (CM) in Chongqing, China during 2007-2009. Tree vigor, yield and quality were 

investigated and compared for three consecutive years. The experiment was arranged in randomized 

block design, three replications and five trees per plot. The scion cultivars ‘Hamlin’ orange, ‘Tongshui 72-1 

Jincheng’, and ‘Trovita’ orange grafted on ‘R 16-6’ all showed excellent performance as did ‘Tongshui 72-1 

Jincheng’ and ‘Trovita’ orange on ‘Rangpur’ Lime (RL), with strong or medium tree growth vigor, highest 

yield, yield efficiency, and best fruit quality. ‘Hamlin’ orange and ‘Tongshui 72-1 Jincheng’ on ‘Pomeroy’ 

trifoliate (PT) and ‘Volkamer’ lemon (VL) also showed good productivity and fruit quality with a smaller 

tree canopy, and could be planted more densely. ‘Rich 16-6’ trifoliate, PT, VL, and RL are the most suitable 

rootstocks for ‘Hamlin’, ‘Tongshui 72-1 Jincheng’ and ‘Trovita’ orange. Additionally, PT and VL can be used 

for high-density cultivation. 

S18P27 

Effects of six rootstocks on tree growth, fruit quality and N, P, K content of lemon 

Hong L., and Xie Y.H. 

Chongqing Academy of Agricultural Sciences (CAAS), Fruit Research Institute, China. cqxieyh@hotmail.com 

The present experiment was carried out to screen proper rootstock for ‘Fino 47’ lemon. We had analysed 

tree growth, fruit quality and annual dynamic changes of N, P, K content of leaves using ‘Fino 47’ lemon 

grafted with six different rootstocks. Differences were found in both the vegetative and reproductive 

growth of different treatments. The trees on ‘Carrizo’ citrange had the highest tree height and crown 

diameter. Whilst, growth of new branches on ‘Carrizo’ citrange and ‘Swingle’ citrumelo became more 

than other treatments. The trees on ‘Volkamer’ had largest number of terminal branches. In addition, 

the flowering behavior of different treatments was not the same. Spring blossom of three-year-old trees 

on ‘Swingle’ citrumelo was highest of all, however ‘Junos’ with highest autumn blossom. In the aspect of 

fruit quality, the largest fruit weight was gotten from trees on ‘Swingle’ citrumelo. The largest content of 

total acids and soluble solids were gotten from trees on ‘Volkamer’. The pericarp was thinner and oil cells 

smaller using ‘Trifoliate’ and ‘Junos’ as rootstocks. Fruit on ‘Junos’ had highest juice content, while lowest 

on ‘Red’ tangerine. The rootstocks did not influence the annual dynamic changes of N, P and K in leaves, 

only influenced the contents of mineral nutrient in leaves at different stages. We came to the conclusion 

primarily that ‘Volkamer’ and ‘Swingle’ citrumelo were suitable rootstocks for ‘Fino 47’ lemon, therefore 

may be extended for demonstration and production. 


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S18 

S18P28 

Tree performance and fruit quality evaluation of ‘Shatangju’ mandarin grafted on four rootstocks 

in South China 

Liu X. 1 , Huang M. 1 , Li J. 2 , Chen J. 1 and He Y. 1 

1 College of Horticulture, South China Agricultural University, China; and 2 Zhongkai University of Agriculture and Engineering, China. 

willderliu@gmail.com 

‘Shatangju’ (Citrus reticulata), a delicious fresh fruit variety of citrus, is native to South China. Its fruit is 

orange red, thin skin and easy peeling, and now it’s one of the largest economic benefit fruits in South China. 

But very few studies have been conducted on rootstocks for ‘Shatangju’ in China. So, a field experiment 

with ‘Shatangju’ grafted onto 4 rootstocks was carried out in Guangdong Province, to compare rootstock 

performance and to make its comprehensive evaluation by principal component analysis (PCA). The evaluated 

rootstocks were: ‘Trifoliate’ orange (Poncirus trifoliata), ‘Canton’ lemon (Citrus limonia), ‘Red’ tangerine (C. 

reticulata) and ‘Sour’ tangerine (C. reticulata). The trees, planted in 2002, were arranged in a randomized 

block design, with five replicates and one plant per plot. After 2 successive years of evaluation, results showed 

that trees grafted on ‘Trifoliate’ orange and ‘Canton’ lemon were dwarfing and the others were vigorous. 

Fruits from ‘Canton’ lemon rootstock were largest and had lowest edible rate, while fruits on ‘Trifoliate’ 

orange were smallest but had the reddest color. The effects on fruit internal quality were irregular. The results 

from PCA by SPSS showed that the score of ‘Canton’ lemon rootstock was highest in both years. PCA proved 

to be a very effective procedure to obtain a synthetic judgment of rootstocks. 

S18P29 

Influence of different rootstock type on chlorophyll content and mineral elements concentration 

in scion of ‘Kinnow’ mandarin 

Hosseini Farahi M. 1 , Aboutalebi Jahromi A. 2 and Hasanzada H. 3 

1 Young Researcherch Club, Yasouj Branch, Islamic Azad University, Yasouj, Iran; 2 Department of Horticulture Science, Jahrom Branch, 

Islamic Azad University, Jahrom, Iran; and 3 M.Sc in Horticulture and Specialist of Minab Agricultural Research Station, Iran . 

m.hosseini.farahi@gmail.com 

The aim of this work was evaluated the effect of the 4 citrus rootstocks: sour orange (Citrus aurantium), 

‘Bakraei’ (Citrus reticulata × C. aurantium), ‘Mexican’ lime (Citrus aurantifolia) and ‘Volkamer’ lemon (Citrus 

volkameriana) on chlorophyll content and mineral elements (N, P, K, Ca, Mg, Na, Fe, Zn, Cu, Mn, Cl and B) 

in scion’s leaf of ‘Kinnow’ mandarin (C. reticulata) grown in pot containing calcareous soil in greenhouse as 

completely randomized design with 4 replications. Results showed that rootstocks had significant effects 

on leaf chlorophyll content. The greatest chlorophyll content obtained on ‘Volkamer’ lemon rootstock. The 

rootstock types had significant effect on leaf mineral concentrations except of Cl, P, Cu, Mn and Zn. Leaf N and 

Mn concentration was lower than optimum range on all rootstocks, K on ‘Mexican’ lime rootstock and Ca on 

all rootstocks except ‘Mexican’ lime. The scions on sour orange had the highest Cl. Na concentrations was the 

highest on ‘Mexican’ lime rootstock. 

S18P30 

Preliminary studies on high density planting of some citrus cultivars to obtain a more rapid 

recovery of investment capital 

Bassal M.A. 

Suez Canal University, Faculty of Agriculture, Horticulture Department, Egypt. magdy_bassal@yahoo.com 

‘Clemenules’, ‘Hernandina’ and ‘Nova’ mandarins budded on sour orange rootstock were planted at two 

planting spacing of 2x5 m and 5x5 m to obtain economic yields earlier in the lifespan of the orchard. 

Annual fruit production plus cumulative and average yield per tree and per acre were estimated during five 

production seasons, from 3rd to 7th years after planting (YAP). In addition, tree height, canopy diameter and 

circumference, tree volume, and trunk girth were determined in the 6th and 7th YAP. Trees planted at 2x5 m 

were significantly taller than those planted at 5x5 m, but the canopy volume of trees planted at 5x5 m was 


larger, while trunk girth was not affected by tree spacing in the 6th and 7th YAP. On the other hand, trees of 

‘Nova’ mandarin had the smallest canopy diameter and circumference compared to those of ‘Hernandina’ 

and ‘Clemenules’ clementine, while ‘Clemenules’ trees had the greatest height and volume. The yield per 

acre from trees planted at 2x5 m was consistently higher than those planted at 5x5 m. Yields from the higher 

density planting were about 454%, 221%, 137%, 76% and 90% greater than those from the lower density, 

in the 3rd to 7th YAP, respectively. Cumulative yield (over 5 years) per acre from closely planted trees was 

40 tons (117%) more than that from widely spaced trees. This means that growers can obtain about 117% 

more economic return from the same land area with approximately the same cost of production. Cumulative 

and average annual yield per tree indicated that ‘Hernandina’ and ‘Nova’ cultivars were significantly more 

productive than ‘Clemenules’ under the conditions of this study. 


S18

Session 20 

CITRUS AND HEALTH 

S20

S20O01 

Flavanones are involved in the cardiovascular protective effects of citrus fruits 

Morand C. 

Human Nutrition Unit, UNH-UMR 1019, INRA, Centre de Recherche Clermont/Theix, France. christine.morand@clermont.inra.fr 

Although it is widely known that consuming fruits rich in polyphenols has a beneficial effect on health, 

it is more difficult to attribute a protective effect to a particular compound. As suggested by several 

epidemiological studies citrus fruits could be largely involved in the beneficial effect of fruits consumption on 

cardiovascular health. Citrus fruits provide vitamin C, carotenoids and they are also exclusive and abundant 

sources of flavanones, a particular class of dietary polyphenols. Until recently the role of these bioactive 

compounds in vascular protection was still far from being elucidated. By performing clinical trials, preclinical 

studies and in vitro experiments, we have examined the specific effects of the major flavanones in orange 

(hesperidin) and grapefruit (naringin) on vascular protection. In healthy overweight men, we showed that 

a 4 week consumption of orange juice or hesperidin significantly reduced diastolic blood pressure and 

both significantly improved postprandial vascular reactivity. Both also significantly affected leukocyte gene 

expression with over 1.000 genes up-regulated by both orange juice and hesperidin, involved in chemotaxis, 

adhesion, infiltration and lipid accumulation, processes involved in atherosclerosis development. In mice, 

naringin consumption protected from diet-induced atherosclerosis with a marked reduction of lipid deposit 

and modulated expression of genes in aorta implicated in cell adhesion and transendothelial migration. In 

vitro, flavanone metabolites significantly attenuated monocytes adhesion to TNFα-activated endothelial cells 

and decreased the expression of some atherogenic genes, like cell adhesion molecules or chemokines. In 

conclusion, taken together, these results suggest a beneficial impact of citrus flavanones on vascular health 

that could be highly mediated through genomic effects. 

S20O02 

Health benefits of citrus: recent advances and future outlook 

Patil B.S., Jayaprakasha G.K., and Uckoo R.M. 

Texas A&M University (TAMU), Vegetable and Fruit Improvement Center, Department of Horticultural Sciences, USA. 

b-patil@tamu.edu 

Citrus fruits have a multitude of health promoting properties and in the past few decades, research has 

made significant contributions in connecting specific health benefits to a group of secondary metabolites 

called bioactive compounds. These compounds have been isolated and investigated for their potential roles 

in improving human health, such as in reducing the risk of chronic diseases including cancer, cardiovascular 

diseases and osteoporosis. Also, in recent years, a worldwide surge in the consumer demand for these 

delicious and healthy fruits has led to increased production. However, different production systems and postharvest 

factors may affect citrus bioactives, thus altering the healthfulness of the fruit. Here, the influence of 

specific pre-and post-harvest factors on the levels of bioactives and their relevant biological activities will be 

discussed. Research at the Vegetable and Fruit Improvement Center on “farm to consumer” aspects of citrus, 

specifically in grapefruit, will be presented, including varying production systems, testing biological activities 

using cell culture and animal models and conducting human intervention studies. -The present research report 

is based upon work supported by USDA-NIFA #2010-34402-20875 “Designing Foods for Health” through the 

Vegetable & Fruit Improvement Center. 

S20O03 

Orange and grapefruit bioactive compounds, citrus consumption and health benefits 

Cancalon P., and King D. 

Florida Department of Citrus (FDOC), Scientific Research, USA. dking@citrus.state.fl.us 

Some of the health benefits of citrus fruits may be attributed to specific bioactive compounds. Citrus are 

rich in flavonoids, the two more prominent being hesperidin in oranges and naringin in grapefruit. The citrus 

phytochemical matrix also contains other potentially bioactive compounds such as carotenoids, limonoids 


S20

S20 

and ascorbic acid, acting individually or in concert. Recent human clinical studies suggest that citrus bioactives 

provide most of their beneficial effects via processes targeting one or more steps of chronic inflammation 

processes. Long term inflammation is considered to be a key element in the development of many chronic 

diseases: cardiovascular diseases, metabolic syndrome, osteoporosis, dementia and some forms of cancer. 

Citrus phytochemicals appear to act through their metabolites by modulating complex biochemical pathways, 

signalling pathways, or differential expression of specific disease-related genes. The establishment of healthbeneficial 

‘causes and effects’ associated with consumption of citrus fruit and juice products has been the 

focus of a significant number of recent clinical studies. A review of human clinical studies, and relevant 

supportive evidence, will be reported. 

S20O04 

Effects of a long-term grapefruit juice consumption on vascular protection and bone metabolism: 

a controlled randomized cross-over study in post-menopausal women to determine the specific 

role of naringin 

Habauzit V1 , Verny M.A. 2 , Milenkovic D. 2 , Pickering G. 1 , Duale C. 1 , Bayle D. 2 , Thien S. 2 , Rambeau M. 2 , Mazur A. 2 , Horcajada 

M.N. 2 , Dubray C. 1 , and Morand C. 2 

1Centre Investigation Clinique, CIC-CPC INSERM 501, Centre Hospitalier Universitaire, Clermont-Ferrand, France; and 2INRA, UMR 

1019, Unité de Nutrition Humaine, France. christine.morand@clermont.inra.fr 

The consumption of some specific polyphenol-rich foods (cocoa, green tea or soya products) has been 

associated with improvement in several intermediate markers of risk related to cardiovascular disease (CVD) 

and osteoporosis. Citrus fruits also constitute dietary polyphenol-rich sources; however clinical evidence of 

the role of polyphenols in citrus health effects is less consistent. 

We aimed at 1) characterizing the effect of a long-term consumption of grapefruit juice on both vascular 

and bone protections in humans and 2) assessing the specific role of its main bioactive phenolic (naringin) 

in the observed effects. Fifty-two healthy post-menopausal women (non-smoking, aged 50-65 years, 3-10 

years since menopause, waist size > 88 cm) were enrolled in a randomized, controlled cross-over trial. For 

two periods of 6 months, subjects consumed 340 ml/d of either a grapefruit juice (providing 100 mg naringin 

per serving) or a control beverage mimicking the composition of juice but without naringin. Beyond the 

monitoring of the effect of treatments on conventional risk factors for CVD, the main outcomes were the 

evaluation of endothelium-dependent vasoreactivity, in both macro- and microcirculation (brachial FMD 

and PAT signal), and arterial stiffness (carotid-femoral PWV). Regarding bone metabolism, the main outcome 

measured was impact on bone mineral density at multiple sites. The statistical analyses of the obtained data 

are currently going on. 

S20O05 

Effect of technological treatments on the bioavailability of flavanones from orange 

Vallejo F. 1 , Tomás-Navarro M. 1 , Carbonell J.V. 2 , Navarro J.L. 2 , and Tomás-Barberán F.A. 1 

1Centro de Edafología y Biología Aplicada del Segura (CEBAS-CSIC), Ciencia y Tecnología de Alimentos, España; and 2Instituto de 

Agroquímica y Tecnología de Alimentos (IATA-CSIC), Ciencia de los Alimentos, España. fvallejo@cebas.csic.es 

The effect of solubility and concentration of citrus juice flavanones on their bioavailability was evaluated. 

Fresh squeezed orange juice (FS) and orange juice produced by two different technological processes (High 

Pressure Homogenization (HPH) and Pasteurization (P)) were compared. Dissimilar flavanone precipitations 

among treatments were observed. Thus, HPH treatment kept in suspension through soluble part higher 

amount of flavanones increasing therefore their bioavailability. The cultivars studied were ‘Ortanique’ and 

‘Lane Late’. The study was carried out in healthy volunteers (n=18) following the administration of 400 mL of 

orange juices and 24-h urine collection. The determination of the total amount of flavanones present in the 

supernatant and pellet of juices was measured by HPLC-ESI-MSn. The total excretion of Phase II metabolites 

in all volunteers was quantified by UPLC-QqQ using the relevant standard metabolites produced by organic 

synthesis (glucuronidated and sulfonated flavanone metabolites). 


S20O06 

Evaluation of the anticancer activity on prostate cancer by low molecular weight citrus pectin 

Lu S. 1 , Chen J. 1 , Yin Y. 2 , Xia Q. 1 , Zhang J. 1 , and Yang Y. 1 

1 Zhejiang Academy of Agricultural Sciences (ZAAS), Institute of Food Science, China; and 2 Zhejiang Normal University (ZNU), College 

of Chemistry and Life Science, China. lushengmin@hotmail.com 

Low molecular weight citrus pectin (LMCP) was prepared by treating commercial citrus pectin (CP) 

at 121ºC for 30 min and then lyophilized. The molecular properties including weight, galacturonic acid 

content and degree of esterification (DE) of LMCP and CP were determined, and their resistance capacity 

on hormone-independent prostate cancer PC3 cells in vitro was investigated as well. Galatin-3 levels in 

PC3 cells were detected using Northern blotting. The results indicated that the average molecular weight 

(Mp), galacturonic acid content and DE of LMCP were 6685u, 78% and 38% respective in LMCP compared 

to 55,654 u, 64% and 59% respectively in CP. Both CP and LMCP had inhibitive activities to PC3 vitality in a 

dose-dependent manner, however, LMCP had stronger inhibition capacity against PC3 cells. The inhibition 

of LMCP in middle dose (2.5 mg/mL) to PC3 cell viability was 38%, and the inhibition rate increased to 80% 

~90% when treated with LMCP in high dose (5-10 mg/mL). The IC50 for inhibiting PC3 cells proliferation was 

3.55±0.44 mg/mL. Galactin-3 level in PC3 cells treated with 10 mg/mL LMCP had no significant difference 

with that in the control cells, which indicated that the anticancer activity of LMCP on PC3 cells might have 

no relation with galactin-3 levels. 

S20O07 

A molecular approach to characterize the accumulation of ascorbic acid in citrus fruits 

Alós E, Legaz P., Rodrigo M.J, and Zacarías L. 

Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Food Science, Spain. ealos@iata.csic.es 

Citrus fruits are widely recognized by their concentration of vitamin C and therefore as one of the major 

sources of ascorbic acid (AsA) for human nutrition and health. Moreover, AsA is the most abundant 

antioxidant present in plant cells and plays important roles in many developmental and stress processes. The 

biosynthesis of AsA in higher plants has been elucidated recently and to date four, somehow interlinked, AsA 

biosynthetic pathways have been proposed; namely the L-Galactose, the L-Gulose, the Myo-inositol and the 

D-Galacturonic acid pathways. Despite the relevance of AsA in citrus fruits, the biochemical and molecular 

bases of its synthesis and accumulation are almost unknown. Therefore, the objective of the present work 

has been to initiate a molecular characterization of the metabolic pathways involved in the synthesis and 

accumulation of AsA in citrus fruits in order to understand its regulation and to identify potential key steps of 

the pathway. Nine genes belonging to the four biosynthetic pathways and also to the degradation and recycling 

of AsA have been selected and their expression characterized in peel and pulp of fruit during development 

and maturation. Results in fruits of selected citrus varieties indicate that changes in AsA content appear to be 

regulated not only by de novo biosynthesis of AsA but also by degradation, recycling and transport, and that 

different mechanisms may operate in peel and pulp. 

S20P01 

Protective effect of grapefruit naringin on atherosclerosis development and identification of the 

underlying mechanisms 

Milenkovic D. 1 , Chanet A. 1 , Habauzit V. 2 , Bennetau-Pelissero C. 3 , Berard A.M. 4 , Mazur A. 1 , and Morand C. 1 

1 INRA, UMR1019, Unité Nutrition Humaine, France; 2 Centre Investigation Clinique, CIC-CPC INSERM 501, Centre Hospitalier 

Universitaire, Clermont-Ferrand, France; 3 Université de Bordeaux, ENITA Bordeaux 1, France; and 4 ERU « Facteurs de risque vasculaires 

», CHU-Université de Bordeaux, France. christine.morand@clermont.inra.fr 

The aim of this study was to investigate the anti-atherogenic effect of naringin in a mouse model of 

hypercholesterolemia (mice fed a high-fat/high-cholesterol diet) and decipher its molecular targets in aorta 

using nutrigenomic approach. Dietary naringin supplementation (0.02% wt/wt) for 18 weeks reduced plaque 

progression by 41% compared to controls as well the concentrations of several biomarkers of endothelial 


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dysfunction. Microarray studies performed on aortas demonstrated differentially expressed genes encoding 

proteins involved in cell adhesion, actin cytoskeleton organization or focal adhesion. Expression profile of 

these genes suggested limited immune cell adhesion to endothelial cells (ECs) and infiltration in the intima 

of vascular wall. This hypothesis was strengthened by in-vitro experiments on ECs using naringin metabolites 

at physiologically relevant concentrations. These metabolites significantly reduced monocyte adhesion to 

TNFα-activated ECs. Exposure of both monocytes and ECs to naringin metabolites potentiated their inhibitory 

effect on monocyte adhesion, suggesting that monocytes may also be targets for naringenin metabolites. In 

conclusion, this study revealed that the atheroprotective effect of dietary naringin could be linked to its effect 

on gene networks and cell functions related to leukocyte adhesion and transendothelial migration, processes 

highly involved in the early steps of atherosclerosis development. 

S20P02 

Effect of membrane processing on the radical scavenging activity of juice from IGP product Citrus 

limon from “Rocca imperiale” (south Italy) 

Loizzo M.R. 1 , Tundis R1 , Bonesi M. 1 , Pugliese A. 1 , Di Sanzo G. 2 , Balducchi R. 2 , Verardi A. 3 , and Calabro V. 3 

1University of Calabria (UNICAL), Department of Pharmacy, Health Sciences and Nutrition, Italy; 2ENEA C.R. Trisaia (ENEA), Laboratorio 

Biotecnologie (UTTRI-BIOTEC), Italy; and 3University of Calabria (UNICAL), Department of Engineering Modeling, Italy. 

vincenza.calabro@unical.it 

Citrus limon from “Rocca imperiale” was awarded the IGP (Protected Geographical Indication) denomination 

in 2012. The juice is characterized by yellow colour and a sweet taste. Juice obtained by manual pressure of 

C. limon was firstly centrifuged and then concentrated with ultrafiltration process (carried out on Osmonics® 

module, by using a polysulphone membrane, cut off 150 kDa, under d transmembrane membrane pressure 

ranging from 0.5 to 2 bar) with the aim to concentrate and separate the antioxidants. Samples of permeate 

and retentate were continuously collected and analysed in order to measure the amount of antioxidant in 

each flow stream. Considering that antioxidant compounds may act in vivo through different mechanisms of 

action, no single method can fully evaluate the antioxidant capacity of food since levels of single antioxidant 

in food do not necessarily reflect their antioxidant activity. For this reason permeate and retentate juices 

were evaluated for their radical scavenging activity through DPPH and ABTS assay. Permeate samples showed 

a percentage of inhibition of ABTS∙ from 35.97 to 54.27 using pure products while retentate samples exhibited 

a percentage of inhibition 22.67 to 43.66 using pure products. In DPPH assay IC50 values v/v -ranging from 

3.46.64 to 10.64 for permeate and from 7.64 to 8.70 for retentate, respectively. 

S20P03 

The effect of time and refrigeration on bioavailability of flavanones in healthy volunteers after 

fresh squeezed orange juice consumption 

Tomas-Navarro M., Vallejo F., and Tomás-Barberán F.A. 

Centro de Edafología y Biología Aplicada del Segura (CEBAS-CSIC), Ciencia y Tecnología de los Alimentos, Spain. 

mtomas@cebas.csic.es 

The effect of both temperature and time is unclear yet on flavanones bioavailability. A comparison between 

ingestion of freshly squeezed orange ‘Lane Late’ juice and the same juice after a 24h refrigeration period 

(8 ºC) in the fridge was carried out. This study was developed in healthy volunteers (n=7) following the 

administration of 400 mL of freshly squeezed orange juice (FS) and 24 h urine collection. The same operation 

was done with the refrigerated one (FR). The determination of the total amount of flavanones present in the 

supernatant and pellet of both juices was measured by HPLC-MS. Significant differences were observed in 

flavanones precipitation (pellet) after 24 h refrigeration (FR) compared to the freshly squeezed one (FS). The 

total excretion of flavanone metabolites in all volunteers decreased between 2 and 5-fold after storage for 24 

h at 8 ºC (FR). The results show that research on technological and biotechnological methods to preserve the 

bioavailability of the freshly squeezed juice are necessary in order to obtain processed juice with the highest 

bioavailability. 


S20P04 

The leaves of Mediterranean mandarin could be used as an important source of hesperidin, 

nobiletin and tangeretin. 

Durand M.V.S. 1 , Fanciullino A-L. 2 , Jay-Allemand C. 3 , Ollitrault P. 1 , Froelicher Y. 1 , and Bidel L.P.R. 4 

1 UMR AGAP, CIRAD, F-20230 San Giuliano, France.; 2UR 1103 GEQA, INRA, F-20230 San Giuliano, France; 3 UMR DIADE, Université 

Montpellier II, F-34095 Montpellier, France.; and 4UMR DIADE, INRA, F-34060 Montpellier, France. durand@corse.inra.fr 

Citrus are rich in flavonoids such as flavones and flavanones. Recent studies have shown that these 

phytonutrients play a beneficial role for human health. Citrus plants can contain high levels of hesperidin, a 

flavanone which is effective in the treatment of chronic venous insufficiency. Nobiletin and tangeretin are two 

polymethoxylated flavones. Nobiletin has been shown to increase hepatic insulin sensitivity and decrease 

atherosclerosis. Tangeretin may have antiproliferative and anticarcinogenic effects by blocking MAPKs 

activation and ROS generation. Studies on flavonoids from citrus are generally focussed on ripe fruits and on 

one group of metabolites. The aim of this study is to quantify accurately all groups of flavonoid from leaves 

of mandarin (Citrus deliciosa). Flavones and flavanones analysis was carried out by liquid chromatography 

and mass spectrometry (LC-MS) using a new generation column. Moreover, a specific gradient was designed 

to evaluate both flavanones and methoxylated flavones. This method was applied to leaves from mandarin 

tree. All leaves were fully-expanded, and were about one-year-old from the spring flush of the previous 

season. They were of similar height above the ground, had the same east orientation and experienced similar 

exposure to light. Comparison of metabolite levels revealed that mandarin leaves were rich in hesperidin, 

nobiletin and tangeretin. Interestingly, nobiletin and tangeretin also accumulated in high level. 

S20P05 

Comparative study of fruit flavonoids in ten citrus hybrids 

Ran Y. 1 , Zhao Q. Y. 2 , Su X. S. 3 , Chen W. J. 2 , Jiang D. 2 , and Jiao B. N. 1 

1 Citrus Research Institute, Southwest University; College of Food Science, Southwest University, China; 2 Citrus Research Institute, 

Southwest University, China; and 3 School of Chemistry and Chemical Engineering, Southwest University, China. bljiao@tom.com 

Citrus species are a rich source of flavonoids. Numerous epidemiological, clinical, and preclinical studies 

have shown that citrus flavonoids have an anti-inflammatory, anti-cancer, anti-atherosclerosis, antioxidant 

and anti-bacterial activities. Many relevant research reports about citrus flavonoids were focused on the 

determination of flavonoids in different orange and mandarin varieties, and a little about citrus hybrids. In 

this study, 10 citrus hybrids cultivated in Chongqing city, China, were analyzed for 8 flavanone glycosides (FGs) 

and 3 polymethoxylated flavones (PMFs) by the ultra performance liquid chromatography (UPLC). The results 

showed that the total flavonoids in juice are much lower than those in peel. Of all the samples, the total 

flavonoids in ‘Kiyomi’ tangor fruit was the highest, followed by ‘Wanmi No.3’ and ‘Wanmi No.1’. The range of 

the total flavonoid concentration in all juice was from 0.13 to 0.42 mg/g, and from 4.8 to 20.0 mg/g in peel. 

The most abundant flavonoids in 10 citrus hybrids were hesperidin, narirutin, didymin and polymethoxylates 

flavones. The largest amount of narirutin was found in peel of ‘Kiyomi’ tangor, which was 3.87 mg/g; while 

the largest amount of hesperidin and didymin were found in peel of ‘Wanmi No.3’, with the concentration of 

16.07 mg/g and 1.89 mg/g, respectively. Furthermore, neohesperidin was only found in ‘Niushen’ hybrid; the 

content in Niushen’s peel was 4.88 mg/g. The content of total polymethoxylated flavones in ‘Jucheng 1-1232’ 

was the highest of the 10 analysed citrus hybrids, which was 0.94 mg/g. 

S20P06 

Over-consumption of satsuma mandarins is associated with “Shang huo” reaction: results from 

case-control studies 

Ma Z.C. 1 , and Deng X.X. 2 

1 Huazhong Agricultural University (Hzau), College of Horticulture and Forestry Sciences, China; and 2 Key Laboratory of Horticultural 

Plant Biology of Ministry of Education, Huazhong Agricultural University, China. mzhaocheng@gmail.com 

Satsuma mandarin accounted for a large proportion of citrus varieties. It is rich in carotenoids, limonoids and 

some other important functional components, potantially benefitial for human health. Over-consumption 


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of satsuma, however, (even some people just eat one) induces “Shang huo”. This reaction is an itching or 

burning sensation in the lips, mouth, ear canal, and/or pharynx. Sometimes other reactions can be triggered 

in the eyes, nose, and skin. “Shang huo” make people afraid of eating satsuma and have negative impact on 

the citrus planting efficiency. Litchi and longan fruit also produce this kind of effect. This study was focused 

on the analysis of the mechanism of “Shang huo” by a case-control study. 200 volunteers participated in 

the project. In the first night, from 7 pm to 9 pm, male volunteers ate more than 1.5 Kg satsuma at a time, 

and female volunteers ate 1 Kg. This consumption was 2-3 times above normal consumption. Individual 

reactions were carefully observed and recorded for continuous 3 days. Statistically significant differences 

were found. 

S20P07 

Dissipation curves of cypermethrin in whole fruit and mandarin pulp in Argentina 

Kulczycki Waskowicz C. 1 , Sosa A. 1 , Beldoménico H. 2 , García S. 2 , and Repetti M.R. 2 

1National Institute of Agricultural Technology, Concordia Agricultural Experiment Station (INTA, EEA Concordia), Pesticides Residues 

Plant Protection, Argentina; and 2 School of Chemical Engineering, Santa Fe (UNL), Central Laboratory, Pesticide Division, Argentina. 

ckulczycki@correo.inta.gov.ar 

Cypermethrin is a pyrethroid insecticide used for pest control in several crops. The objective was to determine 

a degradation curve of cypermethrin in whole fruit and mandarin pulp. The assay was performed in a plot 

of satsuma mandarin located at INTA’s Agricultural Experiment Station in Concordia during summer 2011. 

The treatment used 25% of cypermethrin at a dose of 60 cm3/hl commercial formulation. The treatment 

was performed with a high volume spray under Good Agricultural Practice. Volume applied was 2916 l/ 

ha. Pesticide degradation in fruit was studied for a 61-day period since insecticide application and included 

periodic samplings. The residue determinations were performed by gas chromatography with ECD detector. 

The quantification limit was 6 µg/kg and the detection limit 3 µg/kg. Fruit diameter and internal quality was 

also determined: juice percentage and maturity rate (ºBrix, % titratable acidity). The first elimination phase 

was fast, from an initial deposit of 0.51 mg/kg to 0.15 mg/kg after 21 days. The second elimination phase was 

slower reaching at the end of the experiment levels of 0.06 mg/kg. No residues were detected in pulp. Fruit 

diameter remained constant throughout the assay; therefore, the dilution factor due to growth of plant tissue 

was not considered. In whole fruit, even though residue levels of cypermethrin were low, presence at the end 

of the assay showed great persistence. 

S20P08 

Dissipation and residue of forchlorfenuron in citrus fruits 

Chen W. J. 1 , Su X. S. 2 , Zhao Q. Y. 1 , and Jiao B. N. 1 

1Citrus Research Institute, Chinese Academy of Agricultural Sciences, China; and 2Chemistry and Chemical Engineering, Southwest 

University, China. suxuesu@163.com 

The dissipation and residue of forchlorfenuron in citrus fruits under field conditions were studied. The 

field trial was conducted in Guangzhou, Zhejiang and Hainan provinces, China. An analytical method using 

QuEChERS cleanup and ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/ 

MS) was successfully applied to analyze forchlorfenuron in citrus fruits. The recoveries of forchlorfenuron 

were found in the range of 82.8%-95.5% at three spike levels, with relative standard deviations of 2.1-%- 

8.0-%. The results showed that the degradation rate of forchlorfenuron in citrus fruits followed the firstorder 

kinetics equation C=A∙eBt.The half-live of forchlorfenuron were 15.8-23.0 days. The degradation rate 

of forchlorfenuron in citrus at 42 days (2010) and 52 days (2011) were 82.4-86.4% and 80.6-88.3%. The 

results of final residual trial revealed that when the citrus plants were sprayed at 1-2 times successively at the 

concentration of 20 mg ai/L and 30 mg ai/L, the residues in pulp of citrus fruits were lower than 0.003 mg/kg 

and most of the residues were concentrated in the peel. The results could give a reference for MRL setting of 

forchlorfenuron in citrus fruits in China. 


S20P09 

Dissipation and residue of 2,4-D in citrus fruits 

Chen W. J. 1 , Su X. S. 2 , Zhao Q. Y. 1 , and Jiao B. N. 1 

1 Citrus Research Institute, Chinese Academy of Agricultural Sciences, China; and 2 School of Chemistry and Chemical Engineering, 

Southwest University, China. bljiao@tom.com 

The dissipation and residue of 2,4-D in citrus fruits under field conditions were studied. The field trial was 

conducted in three provinces of China. An analytical method using QuEChERS cleanup and ultra performance 

liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was successfully applied to analyze 2,4-D 

in citrus fruits. The recoveries were in the range of 85.0-%-107.8-% at three spike levels with relative standard 

deviations of 1.0-%-4.6-%. The results showed that the dissipation kinetics of 2,4-D in citrus fruits did not 

follow with the first-degree reaction pattern. The degradation rate of 2,4-D in citrus at 65 days (2010) and 75 

days (2011) were 42.7-77.3% and 31.2-59.1%. The terminal residues in pulp peel and whole fruits were all 

bellow the maximum residue limit (MRL) value set by European Union (EU) (1 mg/kg). Two supervised trials 

on the post-harvest use of 2,4-D on orange and ‘Ponkan’ mandarin were also conducted. The residues of 2,4- 

D at day 0 in orange samples treated with the 200 mg ai/L 2,4-D solution and in ‘Ponkan’ samples treated with 

the 250 mg ai/L 2,4-D solution were 0.122 mg/kg and 0.265 mg/kg, respectively, both bellow the MRL set 

by EU. The degradation rate of 2,4-D in orange and ‘Ponkan’ fruit after 96 days and 93 days were 55.6% and 

76.5%. Hence it was safe for the use of 2,4-D and the results could give a reference for MRL setting of 2,4-D 

in citrus fruits in China. 

S20P10 

Effect of pesticide spray volumes and doses on the production of marketable lemons in Tucumán, 

Argentina 

Salas López H. 1 , Mansilla C. 2 , Figueroa D. 1 , Carrizo B. 1 , Rojas A. 1 , Campos A. 1 , and Goane L. 1 

1 Estación Experimental Agroindustrial Obispo Colombres (EEAOC), Fruticultura, Argentina; and 2 CITRUSVIL, Argentina. 

hsalas@eeaoc.org.ar 

Current management of lemon trees includes different pesticide volumes and doses. Field trials were 

conducted in lemon orchards located in two climatically and ecologically different regions throughout 

three years to evaluate the impact of three spray volumes (10000, 5000 and 2000 L/ha) and three doses of 

pesticides (high, medium and low) on lemon fruit health. The highest pesticide dose consisted of 15 kg/ha 

of a commercial product of copper hydroxide (53.8%), 100 L/ha of mineral oil and 2 L/ha of a commercial 

product of abamectin (1.8%); medium and lowest doses had the same components, but different quantities: 

the medium 7.5 kg, 50 L and 1 L, respectively, and the lowest 3 kg, 20 L and 0.4 L per hectare respectively. 

Trials were conducted in a randomized complete block design with four replicates. Healthy fruit percentage 

was estimated at harvest from approximately 2.000 fruits per plot. Damaged fruits were separately analyzed 

to discriminate the main cause for rejection: wind, pests or diseases. Independently of doses, healthy fruit 

proportion was significantly higher in plots sprayed with high and medium pesticide volume. Such treatments 

were more efficient for controlling pests (mealybugs, mites and thrips) mainly, although they resulted in a 

higher proportion of fruit damaged by wind. The study demonstrated that a reduction of pesticide spray 

volume (to 5000 L/ha) and doses is possible without affecting fruit quality. 


S20

Session 21 

POSTHARVEST AND JUICE 

PROCESSING TECHNOLOGY 

S21

S21O01 

Biochemical and molecular mechanisms involved in mandarin flavor deterioration after harvest 

Tietel Z., and Porat R. 

ARO (The Volcani Center), Dept. of Postharvest Science, Israel. rporat@volcani.agri.gov.il 

The sensory preference of mandarins declines during storage and transport mainly due to a decrease in 

perception of acidity and typical mandarin aroma and accumulation of off-flavors. Aroma profiling analysis of 

homogenized segments of Or and Mor mandarins conducted by gas chromatography mass spectrometry (GC- 

MS) revealed that the contents of some aroma volatiles, mainly aldehydes and terpenes, somewhat decreased 

during storage, whereas contents of other volatiles, especially the ethanol fermentation metabolites ethanol 

and acetaldehyde, and various ethyl esters which are fatty acid and amino acid catabolism products significantly 

increased during storage. These biochemical observations were further supported by complimentary 

genome-wide transcript profiling analysis studies conducted using the Affymetrix Citrus Genome Array, which 

revealed correlative increases in gene expression patterns related to ethanol fermentation metabolism and 

lipid and amino acid catabolism. Overall, we propose that simultaneous induction of ethanol fermentation 

metabolism and lipid and amino acid catabolism, most probably for energy production means, are involved in 

causing off-flavors in mandarin fruit after harvest. Furthermore, we propose that high levels of ethanol serve 

as substrates for subsequent downstream esterification reactions with acyl-CoA’s derived from fatty acid and 

amino acid catabolism; a reaction catalyzed by alcohol acyl transferases (AAT’s), which results in accumulation 

of various ethyl esters volatiles imparting undesired off-flavor odors. 

S21O02 

Traceability of citrus fruit using isotopic and chemical markers 

Fabroni S., Amenta M., and Rapisarda P. 

CRA Centro di Ricerca per l’Agrumicoltura e le Colture Mediterranee (CRA ACM), Italy. simona.fabroni@entecra.it 

Sicilian citriculture is currently involved in a marked crisis mainly related to the lack of a commercial strategy 

along the whole chain of production. This crisis can be overcome focusing on typical citrus productions, 

which have been awarded PGI (Protected Geographical Indication) status by the European Commission. Thus 

it comes the need of a system of traceability to verify the authenticity of these productions. The aim of 

this research was to classify, by a chemical and chemometric approach, Sicilian typical citrus productions 

(Arancia Rossa di Sicilia and Limone di Siracusa) whose geographical origin was authenticated by samplings 

made in PGI or not-PGI areas. The joint use of chemical (quality parameters), spectral (NIR spectral patterns) 

and isotopic (13C/12C, 18O/16O, 2H/1H) markers has revealed that a representative database of each 

geographical area can be used for the development of a traceability system of such typical productions. 

Besides, a growth potential for the Sicilian citriculture is the conversion to organic production. Thus, the 

question of the authenticity of foods labeled as organic becomes an imperative requirement. Our recent 

researches, aimed at identifying new markers by monitoring the δ15N and other components derived from 

primary and/or secondary metabolism in citrus fruits from organic and conventional commercial farms and 

experimental fields, have shown that δ15N analysis may contribute to the differentiation between organic 

and conventional fruit. Moreover, in case of supply of organic fertilizers in conventional regime, a model of 

multivariate analysis, including δ15N and other quality parameters (TSS, TA, ascorbic acid, total polyphenols, 

ORAC units), can contribute to a reliable discrimination between organic and conventional fruit. 

S21O03 

Fluctuation of limonin and nomilin content in different tissues during fruit development of three 

sweet orange varieties 

Wu Houjiu, Tan Anqun, Wang Hua, Ma Yaqing, Sun Zhigao, Huang Xuegen, and Guo Li 

National Research Center for Citrus Engineering Technology Citrus Reseach Institute, Southwest University (NRCCET), China. 

wuhoujiu@126.com 

In this study, limonin and nomilin content in different tissues of fruit at different developmental stages of 

three sweet orange varieties (Citrus sinensis), ‘Xuegan’ ‘No 7 Zhongyu Jincheng’ and ‘Fengqi’ navel were 


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determined by HPLC. Results indicated that the limonin level in the peel of the three sweet oranges at 

different developmental stages was lower than that of nomilin, but limonin levels in sacs were higher than 

that of nomilin. The nomilin content was three folds that of limonin in seeds of ‘Xuegan’. The limonin content 

in the ‘Xuegan’ peel gradually decreased with the fruit development. The nomilin content dropped from 

2.090 mg.g-1 in August to 0.326 mg.g-1 in December. Over the same period of time, the limonin content 

declined from 3.288 mg.g-1 to 0.894 mg.g-1. The trend of limonin and nomilin levels in peels of the other two 

orange varieties were the same as in ‘Xuegan’. Following fruit development, limonin and nomilin contents in 

sacs of the three sweet oranges showed a downward trend, but the limonin content was much higher than 

the nomilin content. The contents of the two limonoids in ‘No 7 Zhongyu Jincheng’ were the lowest among 

all the varieties. The limonin content in sacs of ‘Fengqi’ navel was the highest, and remained 0.211 mg.g-1 in 

November when close to harvesting, which gave a more bitter taste 42 times than the threshold (0.005 mg.g- 

1). The results suggested that the limonin was transferred to the sacs during fruit development in ‘Fengqi’ 

navel fruit, but accumulated in the seeds in ‘Xuegan’. 

S21O04 

Post-harvest management of citrus fruit in South Asian countries 

Ladaniya M. 

National Research Centre for Citrus (NRCC), ICAR, India. msladaniya@gmail.com 

South Asian countries including: India, Pakistan, Bangladesh, Nepal, Bhutan and Sri Lanka produce about 

11.10 million tons of citrus fruits, contributing to roughly 11.0% of world output. Citrus is among the top three 

fruits in the region. With a population of 1604 million, the per capita /annum citrus fruit availability is 6.90 kg. 

Mandarin and sweet orange are major citrus fruits constituting 84%, followed by acid lime, lemon and other 

citrus (16%). Postharvest management is mostly on conventional lines. In North-west India and Pakistan, 

‘Kinnow’ is sorted, washed, waxed and packed in modern packing houses. Harvesting is done by clippers for 

‘Kinnow’, by snapping for ‘Nagpur’ mandarin and by bamboo harvesters for ‘Khasi’ mandarin. Total losses 

from farm to retail level in the region are 25-35% and vary with season and commodity. Acid lime losses 

increase with onset of monsoon. Wooden boxes are used for mandarins. Oranges and acid limes are packed 

in jute bags. Bamboo container ‘doko’ is used in Nepal, Bhutan and NEH region of India for ‘Khasi’ mandarin. 

Transportation of loose fruit in trucks is common. Refrigerated storages and modern packinghouses are being 

established. Citrus fruits are being sold in supermarkets. Modified atmosphere packaging increased shelf life 

of mandarins up to 3 weeks. Evaporative cool chamber (1.5 -8 tons capacity and very low energy consumption) 

extended storage life of ‘Nagpur’ mandarin, ‘Mosambi’ orange, acid lime, ‘Kinnow’ and grapefruit up to 21, 

40, 30, 60 and 77 days as against 10,14, 5, 14, and 27 days at ambient condition, respectively. Cellar stores are 

used in Nepal and Bhutan. Export of ‘Kinnow’ from Pakistan is increasing. India exported nearly 30000 tons 

of citrus fruits in 2008-09.This paper discusses value chain and post-harvest overview in south Asia including 

postharvest research, conventional and innovative handling, storage structures, modern infrastructure and 

future challenges and prospects. 

S21O05 

A technological platform for the valorization and recovery of outsize and defective PGI citrus 

fruits from South Italy. 

Mazzuca S. 1 , Spadafora A. 1 , Serra I.A. 1 , Bernardo L. 1 , Balducchi R. 2 , Di Sanzo G. 2 , Maccioni O. 2 , Verardi A. 3 , and Calabro V. 3 . 

1University of Calabria (UNICAL), Department of Ecology, ITALY; 2ENEA C.R. Trisaia (ENEA), Laboratorio Biotecnologie (UTTRI-BIOTEC), 

Italy; and 3University of Calabria (UNICAL), Department of Engineering Modeling, Italy. vincenza.calabro@unical.it 

Clementine represents a special kind of citrus fruit, mainly grown in the south of Italy and characterized 

by sweetness, flavour and agreeable taste. The Ionian area of Calabria (Italy), offers a perfect climate for 

lemon crops, like the PGI (Protected Geographical Indication) Lemon of Rocca Imperiale. Selected genotypes 

‘Femminello’ have given well adapted ecotypes and their fruits have excellent fragrance, the finest essential 

oil and sweet juice. Marketing and commercialization of organic fruit present specific and restrictive rules, 

in relation to size, color and taste of the fruit. Usually more than 20% of the organic fruit produced cannot 


e directly commercialized and represents a waste for producers, despite their high quality and richness 

in health benefits. A valid alternative is represented by the processing of outsize and defective fruits to 

produce juices as well as to extract high value active compounds from various parts of the fruits. In this 

paper the authors suggest a technological platform devoted to the recovery and valorization of PGI citrus 

fruits from the South of Italy in order to obtain high added value products that can be distributed and 

commercialized in the organic market and health industry. The technological platform could operate with 

the production of fresh and pasteurized citrus juice from less quality citrus fruits. The authors put their 

attention to the process and technology required to guarantee high quality, taste and stability of juices. 

They studied also the methodologies that could be used for the extraction of active compounds in mild 

conditions, as i.e. membrane processes or supercritical extraction, in order to recovery active substances 

(proteins, antioxidant, terpens) for food, pharmaceutical and chemical industries. The platform will also be 

used for the characterization of fruit anatomy, structure, texture and physiology features, in order to well 

predict the quality of fruit. 

S21O06 

Industrial orange juice (var. ‘Salustiana’) debittering: effects on sensory properties 

Fernández-Vázquez R. 1 , Stinco C.M. 1 , Hernanz D. 2 , Heredia F.J. 1 , and Vicario I.M. 1 

1 Food Colour & Quality Laboratory (FCQL), Department Nutrition & Food Science. Universidad de Sevilla, Spain; and 2 , Department 

Analytical Chemistry. Universidad de Sevilla, Spain. rociofernandezv@us.es 

Debittering is an industrial process that removes bitter taste compounds in juices, which are 

mainly limonoids. This process can be done by physical adsorption on a resin, which can also remove other 

interesting compounds related to the sensory properties. This study was aimed to analyse this effect in orange 

juice (OJ) of ‘Salustiana’ (Citrus sinensis). Samples (n = 9) of the industrial squeezed OJ and corresponding OJ 

after the debittering process (DOJ) were taken in an orange juice factory. Acidity, pH and total soluble solids 

were measured according to AOAC methods. No significant difference between OJs and DOJs were found. 

Colour was evaluated by image analysis (DigiEye System). Hue and lightness were lower (more reddish and 

darker) after debittering (p

S21 

flowers of different cultivars of citron and lemon were analyzed by HPLC/MS-MS. The dominant pigments in 

fruits were cyanidin-3-glucoside and cyanidin-3-(6” malonil-glucoside) while in young leaves and flowers a 

different pattern was observed. This is the first report of patterns of anthocyanins in the different organs of a 

large number of genotypes of citrus. 

S21P02 

Organic acids metabolism in postharvest citrus fruit 

Cheng Y.J., Sun X.H., Zhu A.D., Xu J., and Deng X.X. 

Huazhong Agricultural University (H), Key Laboratory of Horticultural Plant Biology, Ministry of Education, China. 

yjcheng@mail.hzau.edu.cn 

Organic acids in citrus fruits play critical roles in their edible quality and sensibility to storage environments. 

However, very limited information on postharvest acid metabolism in citrus fruit is available yet. In the 

present study, organic acids metabolism in the pulp of 3 main pummelo cultivars (Citrus grandis), widely 

planted in China, including ‘Guanximiyou’, ‘Shatianyou’, and ‘Hirado Bontan’, were systematically analyzed 

in 3 successive growing seasons. Capillary electrophoreses, high performance liquid chromatography and 

gas chromatography mass spectrometry were used for physiological and metabolic analyses. Moreover, an 

8×15K mitochondrial microarray, composing of 1569 functional gene probes was designed. Based upon the 

acid metabolic profiles, RNA was extracted from four key stages for the microarray assaying. Meanwhile, the 

damage of mitochondrial membranes, as well as the contents of reactivate oxygen species was examined. Our 

results demonstrated that during citrus fruit postharvest storage phase: 1) The metabolic profiles of organic 

acid differed among cultivars; 2) Fluctuations of acid contents were inherent properties of in all sound citrus 

fruits; 3) The dynamic equilibrium of organic acid content was determined by the status of acid synthesis, 

degradation, transportation and storage, which were resulted from the synergistic actions of mitochondria, 

vacuoles and peroxisomes; 4) Except tricarboxylic acid cycle (TCA), glutamine and γ-aminobutyric acid (GABA) 

pathway, which linked the primary and secondary metabolisms, also played significant role in citrus fruit acid 

regulation. 

S21P03 

Ethylene degreening treatment under commercial conditions does not cause loss of nutritional 

and aroma quality of citrus fruit. 

Sdiri S., Navarro P., and Salvador A. 

Instituto Valenciano de Investigaciones Agrarias (I.V.I.A.), Centro de Tecnología Postcosecha, Spain. salvador_ale@gva.es 

A significant volume of Spanish citrus fruit production is commonly submitted to degreening with ethylene 

exposure prior to be exported to overseas countries under cold quarantine conditions. Many studies 

have reported the effect of postharvest application of ethylene on internal quality fruit. Nevertheless, 

information about the effect of degreening and quarantine treatments on the nutritional and aroma 

volatile compositions in citrus fruit is scarce. This study aimed to evaluate the effect of degreening with 

and without ethylene exposure followed by cold quarantine treatment on vitamin C, hesperidin, narirutin, 

didymin, sinensetin, nobiletin, tangeretin content as well as antioxidant activity of ‘Navelina’ sweet orange 

and ‘Clemenules’ and ‘Oronules’ mandarins. The levels of the most important aroma active compound in 

citrus fruit (ethanol, acetaldehyde, ethyl butanoate, hexanal, α-pinene, myrcene, ethyl hexanoate, octanal, 

limonene, linalool, nonanal and decanal) were also determined. The response to degreening process and 

the posterior quarantine treatment depended on the variety. Although some changes were observed 

in individual flavonoids compounds of ‘Clemenules’ mandarins and ‘Navelina’ oranges, the degreening 

treatments followed by cold quarantine storage did not induce dramatic changes in nutritional and aroma 

compounds. Nevertheless, ‘Oronules’ mandarins exhibited the highest response to ethylene exposure and 

quarantine treatment with an increase in the level of flavonoids components as well as the level of some 

volatile compounds. 


S21P04 

Change in nonvolatile flavours of blood and common orange fruits during cold storage 

Fabroni S. 1 , Amenta M. 1 , Todaro A. 2 , and Rapisarda P. 1 

1 CRA-Centro di Ricerca per l’Agrumicoltura e le Colture Mediterranee (CRA ACM), Italy; and 2 Università degli studi di Palermo (UNIPA), 

Dipartimento dei Sistemi Agro-Ambientali, Italy. paolo.rapisarda@entecra.it 

Prolonged cold storage may cause relevant changes in volatile and non-volatile components of orange 

fruit [Citrus sinensis], probably associated with the decrement of characteristic fruit flavour and sensory 

acceptability. The aim of this work was to evaluate the changes of nonvolatile components of two blood 

varieties (‘Tarocco’ and ‘Moro’) and a common variety (‘Washington navel’) of orange fruits stored at 6 ± 1 °C 

and 90-95 % RH for 60 days. Taste components such as total and individual sugars (TSS, glucose, fructose and 

sucrose) and acids (titratable acidity, ascorbic acid) were determined during fruit storage. In addition, other 

compounds influencing the sensory characteristics of the fruit such as total anthocyanins, putrescine and 

limonin were evaluated. Sensory assessments were performed by a trained sensory panel at 15 days intervals. 

TSS and TA did not show significant variations during storage in all varieties. Such a trend was confirmed 

by evaluating glucose, fructose and sucrose. Total anthocyanins significantly increased during storage while 

ascorbic acid content remained almost unchanged in all varieties. Limonin significantly decreased in all 

varieties, reaching the lowest values at the end of cold storage. A consistent and significant raise of putrescine 

occurred during storage in the fruit of the blood varieties, while in the common orange variety no significant 

difference was observed. These results are in accordance to those obtained by the sensory evaluation that 

has shown an increase of the descriptor “off-flavour” in the last period of storage only for blood orange fruits. 

S21P05 

Antioxidant capacity and total phenolic contents of bergamot (Citrus bergamia) 

Yilmaz K.U. 1 , Uzun A. 1 , Ercisli S. 2 , Sengul M. 2 , Yildiz H. 2 , and Uysal O. 3 

1 Horticulture Department of Agriculture Faculty of Erciyes University, Kayseri, Horticulture Department, Turkey; 2 Horticulture 

Department of Agriculture Faculty of Ataturk University, Erzurum, Turkey; and 3 Alata Horticultural Research Station Erdemli- Mersin, 

Genetic and breeding, Turkey. onuruysal33@gmail.com 

Bergamot grown in East Mediterranean Region of Turkey is cultivated mostly for its essential oil produced 

from its peel. Except the oil used in fragrant tea (earl grey) making and pharmaceutical industry, bergamot 

peel is also used in jam making. Usually only calcium citrate and citric acid are obtained from bergamot 

juice. With this study, some of the biochemical contents of bergamot juice were determined and its usage 

ways (patterns) were discussed. Two methods, namely β-carotene bleaching and DPPH (α,α-diphenyl-βpycrylhydrazyl) 

assay were used to determine total antioxidant capacity, while Folin–Ciocalteu reagent was 

used to determine total phenols. Bergamot had high total phenolic (80.06 µg GAE/mg DW) and also high 

total anthocyanin content with β-carotene bleaching (60.12%) and with DPPH (180.07 mg/100ml). The study 

demonstrates the potential of bergamot juice for nutritional value through other fruit juices. 

S21P06 

Simulation of cold treatment during a cargo shipment of citrus fruits 

Tauriello A. 1 , Di Renzo G.C. 1 , Altieri G. 1 , Strano M.C. 2 , Genovese F. 1 , and Calandra M. 2 

1 Università degli Studi della Basilicata (UNIBAS), Scuola di Scienze Agrarie, Forestali, Alimentari ed Ambientali, Italy; and 2 Centro di 

ricerca per l’agrumicoltura e le colture mediterranee (CRA ACIREALE), Italy. antonella.tauriello@unibas.it 

Commercial agreements for citrus shipment outside EU countries (Canada and USA) require both the respect of 

the fruit quality and the restriction of parasites spread (Medfly larvas). Both of these requirements are satisfied 

with the correct use of cold treatment during the shipment. This paper reports the results of a simulated 

refrigerated transport of citrus fruits in a 40ft container. Fruit temperature distribution in a refrigerated container 

(MSC 40ft) has been monitored in order to verify the temperature distribution in different positions of the load. 

A refrigerated container placed in the Oranfrizer s.r.l (Scordia-CT Italy) packing house, was loaded in 2 hours, 

starting with pallets placed in the end side of the reefer. For temperature measurements (in the air, in the 


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pallet and in the fruits) 40 digital probes were used. In order to optimize air circulation across fruits boxes, an 

innovative package (with a new designed vented surface) was compared to the standard boxes. Results show 

that the mean temperature difference between the probes placed in the head space was less than 0,5°C. Graphic 

peaks showed the on/off cycle of the automatic defrosting system. The probes placed on the container floor 

demonstrated a good result in terms of temperature homogeneity, but the temperature reached a minimum 

level of about -0,8°C which could be considered too low for citrus fruits storage. The innovative vented boxes 

allowed a more rapid cooling and a more accurate temperature control. 

S21P07 

Application of 3,5,6-TPA under commercial conditions to control calyx senescence associated to 

degreening treatment 

Tormo D. 1 , Conesa E. 1 , Sdiri S. 2 , Navarro P. 2 , and Salvador A. 2 

1 Fomesa Fruitech (FOMESA), Technical Department, Spain; and 2 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de 

Tecnología Postcosecha, Spain. econesa.fruitech@fomesa.net 

Postharvest degreening treatment with exogenous ethylene application is widely used in Mediterranean 

growth area to improve the external coloration of the early-season citrus varieties in which internal maturity 

is achieved when the peel is still green. Nevertheless this treatment can induce physiological disorders overall 

related to calyx senescence. In previous studies has been reported that the application of 3,5,6-trichloro-2pyridyloxyacetic 

acid (TPA) reduces calyx senescence associated to ethylene exposure. However it is important 

to know the effect of this auxin under commercial industrial conditions. 

The purpose of this study was to evaluate the effect of postharvest application of TPA on reduction disorders 

associated to degreening in clementines (‘Clemenpons’ and ‘Clemenules’) in different commercial postharvest 

applications (in drencher and on-line). The application of TPA in drencher very significantly reduces the 

disorders of calyx senescence associated to degreening treatment in clementines, recommending 40 ppm 

of TPA as the most effective dose. The application of TPA ‘on-line’ treatments were effective on reduction 

of calyx disorders, obtaining the best results with 100 ppm of TPA; nevertheless in the trials carried out 

clementines exhibited low susceptibility to calyx disorders after degreening process. The results suggest that 

this auxin could be a good option to control disorders of citrus fruit during degreening treatment. 

S21P08 

Postharvest behavior of new mandarins cultivars obtained at the IVIA 

Sdiri S. 1 , Navarro P. 1 , Cuenca J. 2 , Pardo J. 3 , and Salvador A. 1 

1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Tecnología Postcosecha, Spain; 2 Instituto Valenciano de 

Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; 3 Instituto Valenciano de Investigaciones Agrarias 

(IVIA), Centro de Citricultura y Producción Vegetal, Spain. salvador_ale@gva.es 

A triploid breeding program has been carried out in Plant Protection and Biotechnology Center in the Instituto 

Valenciano de Investigaciones Agrarias (IVIA) based on sexual hybridization, embryo rescue and ploidy analysis 

by flow cytometry in order to obtain new mandarin varieties with late harvest. ‘Safor’ and ‘Garbí’ mandarins 

are new triploid hybrids recently released characterized by their high quality and seedless fruits. In the Citrus 

Center of Citriculture and Vegetable Production (IVIA) other breeding program based on budwood irradiation 

is being conducted in search of new seedless cultivars. At this moment two clones obtained from irradiated 

budwood of the seedy ‘Moncada’ mandarin (‘Moncalina-6S17’ and ‘Manrad-2L09’) are in process of being 

registered and exhibit excellent fruit quality. This study aimed to test the postharvest behavior of these four 

new cultivars. After harvest the fruit were waxed and stored up to 30 days at 1ºC, 5ºC, or 9ºC in order to 

evaluate the sensibility to chilling injury and the changes in quality parameters that occur during the cold 

storage. ‘Safor’ mandarins did not show chilling injury symptoms during 30 days at any temperature studied. 

In contrast, ‘Garbí’ mandarins exhibited susceptibility to chilling injury after 15 days of storage at 1ºC and 5ºC; 

during this period this cultivar showed disorders related with peel dehydration that were aggravated when 

the fruit were late harvested. ‘Moncalina’ and ‘Manrad’ did not show relevant symptoms related to coldinduced 

damage or dehydration at 1ºC, 5ºC or 9ºC for 30 days of storage. For all mandarin cultivars assayed, 

the storage at low temperature was not a limitation for the changes observed in fruit quality parameters. 


S21P09 

Characterization of fruits of four different lemon cultivars, collected in the Northern coast of 

Sicily 

Cupane M. 1 , Guarrasi V. 2 , Palazzolo E. 3 , San Biagio P. L. 2 , and Germanà M. A. 1 

1 Dip. DEMETRA, Università degli Studi di Palermo, Facoltà di Agraria, Italy; 2 Istituto di BioFisica, Consiglio Nazionale delle Ricerche, 

Italy; and 3 Dip. Sistemi Agro–Ambientali, Università degli Studi di Palermo, Facoltà di Agraria, Italy. valeria.guarrasi@pa.ibf.cnr.it 

The present work investigates the properties of the fruits of four main lemon (Citrus limon) varieties 

cultivated in Sicily: ‘Monachello’, ‘Zagara Bianca’, ‘Femminello Santa Teresa’, and ‘Femminello Comune’. 

Physical and chemical properties as well as aroma compounds were analyzed as discriminate factors. Also 

the effect of the storage conditions was verified. Standard experimental techniques were used to determine: 

weight, longitudinal and transverse diameter, pH, titratable acidity, total soluble solids, juice percentage, total 

polyphenols and color index. The volatile components were analyzed by i) gas chromatography with a mass 

spectrometer detector and ii) an electronic olfactory system (“e-nose”) equipped with an array of six MOS 

sensors. Moreover, the composition of peel essential oils was examined. The results suggest that most of the 

analyzed factors allow a good discrimination among cultivars particularly regarding total polyphenols content. 

Also, all the cultivars, especially the ‘Femminello Comune’, maintain the fruit quality, even when stored at 

room temperature, a finding of potential industrial relevance. The present work shows the feasibility of a 

storage protocol with minimal impact allowing energy saving without compromising the physical or chemical 

properties and the aroma characteristics. 

S21P10 

Postharvest green mold control by hot water dips in kumquats 

Vázquez D., Cocco M., Bello F., Panozzo M., and Meier G. 

Instituto Nacional de Tecnología Agropecuaria (INTA), Argentina. fbello@correo.inta.gov.ar 

Kumquats are eaten as a fresh fruit, pulp and peel together. Therefore, non-synthetic products for decay 

control should be applied. This study was conducted to evaluate postharvest green mold (Penicillium 

digitatum) control by alternative methods other than chemicals like application of hot water treatments 

with sodium bicarbonate. Fruit were harvested in Entre Ríos, Argentina, in August 2011. Kumquats were 

wound-inoculated (0.8 mm long, 0.11 mm in diameter) with a conidia suspension (106 spores/ml) and 

dipped in hot water (45ºC, 50ºC, 53°C) or water at room temperature (20°C) for 2 min, with or without 

the addition of 2% sodium bicarbonate and stored at 20°C, 85-90% RH. The counting of rotted fruit was 

performed after 5 and 12 days. Non-inoculated fruit were waxed after water treatments and stored at 5°C, 

34 days (transport simulation) and then at 20°C, 4 days (marketing conditions). Weight loss, firmness and 

physiological disorders were evaluated. In hot water dips at 50 –53ºC, 85% green mold control was observed. 

The addition of 2% sodium bicarbonate to the water showed no significant effect in controlling green mold. 

Weight loss increased with the addition of bicarbonate to the bath and water temperature. However, no 

differences were detected in firmness after the trial. No damage in fruit was observed by hot water dips. The 

use of heat treatments such as hot water dips enables control of green mold in kumquats without altering 

the quality of the fruit. 

S21P11 

Fate of foodborne pathogens in minimal processed orange and reduction of their growth using 

UV-C illumination 

Lourenço A. 1 , Salazar M. 2 , Graça A. 2 , Quintas C. 3 , and Nunes C. 2 

1 Universidade do Algarve. (UAlg), FCT, Portugal; 2 Instituto de Ciências Agrárias e Ambientais Mediterrânicas (ICAAM), Universidade do 

Algarve. FCT, Portugal; and 3 Universidade do Algarve (UAlg), CIQA.IST, Portugal. miguel.salazar@agro-on.pt 

The consumption of minimally processed products increased in recent years and with it the concern of the 

occurrence of outbreaks due to foodborne pathogens. Chlorine is the most commonly used disinfectant, 

however there are concerns about the formation of carcinogenic chlorinated compounds and the limited 


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S21 

effectiveness or completely ineffectiveness of chlorine solutions. The aim of this work was to study the survival 

and growth of Escherichia coli-O157: H7, Salmonella spp. and Listeria innocua and to evaluate the effects of 

two doses of UV-C illumination on reducing their populations in minimally processed ‘Valencia late’ oranges. 

The results indicate that minimally processed oranges were a good substrate for the growth of foodborne 

pathogens. The three pathogens were able to grow in oranges when stored at temperatures of 10 ºC or higher. 

When stored at 5 °C the population remained constant over time, indicating the importance of maintaining a 

cold chain and avoiding contamination. Concerning the use of UV-C as an eco-innovative disinfection system, 

the results showed that the efficacy of UV-C at 3.0 and 7.5 kJ.m -2 and sodium hypochlorite at 100 ppm is low 

for this type of product. The most effective treatment, 30 minutes after application, was (in general) sodium 

hypochlorite and after 6 days the best result was obtained with UV-C at 7.5 kJ.m -2 , indicating the importance 

of good manufacturing practices in processing. 

S21P12 

Evaluation of the effect of ultrasonic variables at locally ultrasonic field on extraction of 

hesperidin from ‘Penggan’ mandarin (Citrus reticulata) peels 

Ma Y.Q 1 , Wu H.J 1 , Ye X.Q 2 , Wang H 1 , and Sun Zh.G. 1 

1 Southwest University, Chinese Academy of Agricultural Sciences (CRI), Citrus Research Institute, China; and 2 Zhejiang University 

(ZJU), Department of Food Science and Nutrition, China. myaya211@163.com 

Ultrasonic power is an important parameter among ultrasonic variables. However, our previous study showed 

that ultrasonic power has a little effect on the yields of hesperidin from ‘Penggan’ peels. Moreover, it has been 

reported that the maximum ultrasonic power depended on the distance of ultrasonic irradiation surface. 

Therefore, to confirm this point, an experiment in ultrasound-assisted extraction (UAE) of hesperidin from 

‘Penggan’ peels at locally ultrasonic field was performed by response surface methodology (RSM). A threelevel 

three-factor Box–Behnken design was applied to evaluate the effects of three independent variables 

(ultrasonic power, time and temperature) on the yields of hesperidin at high and low ultrasonic irradiation 

surface. The results showed that the coefficients of two mathematical-regression models obtained at high and 

low ultrasonic irradiation surface was 0.9742 and 0.9745, respectively, indicating that quadratic polynomial 

model could be used to estimate the ultrasound-assisted extraction of hesperidin. From response surface 

plots, increases of the yields of hesperidin could be significantly dependent on increase of ultrasonic power 

at near ultrasonic irradiation surface. Such properties of ultrasonic power will require further exploration and 

study of highly efficient effects, which can be important for industrial use. 

S21P13 

Industrial orange (var. ‘Salustiana’) juice debittering: effects on the color and bioactive 

compounds 

Stinco C.M. 1 , Fernández-Vázquez R. 1 , Hernanz D. 2 , Heredia F.J. 1 , Meléndez-Martínez A.J. 1 , and Vicario I.M. 1 

1 Food Colour & Quality Laboratory (FCQL), Department Nutrition & Food Science. Universidad de Sevilla, Spain; and 2 , Department 

Analytical Chemistry. Universidad de Sevilla., Spain. rociofernandezv@us.es 

Debittering is a usual practice in the citrus industry worldwide. This process is aimed to remove the bitter 

taste compounds in the juices that are mainly the “limonoids” (limonin, and nomilin). However, the resin 

used for this purpose can also adsorb other interesting compounds from the nutritional and sensory point 

of view. This study was aimed at assessing the influence of industrial debittering process on the colour and 

bioactive compounds of orange juice (Citrus sinensis, var. ‘Salustiana’). Samples (n = 9) of the industrial 

squeezed orange juice (FOJ) and corresponding orange juice after the debittering process (DOJ) were taken 

in an orange juice factory. Carotenoids and vitamin C were analyzed by HPLC and total phenols by the Folin- 

Cicalteu method. Antioxidant activity was determined by TEAC method (Trolox Equivalent Antioxidant Capacity 

Assay for lipophilic and hydrophilic fractions). Results showed that the debittering process had a significant 

effect (p

have any effect on the content of pro-vitamin A carotenoids, nor on the total carotenoid content. Accordingly, 

the total color difference (ΔE*ab) between FOJ and DOJ was 3.28 ± 1.64 CIELAB units, thus slightly appreciable 

(visual discrimination threshold ΔE*ab >3). 

S21P14 

The effect of fermentation on antioxidant content (ascorbic acid, carotenoids and flavonoids) 

and antioxidant activity (abts and dpph values) of orange juice 

Escudero B. 1 , Cerrillo I. 1 , Hornero-Méndez D. 2 , Herrero-Martín G. 1 , Berná G. 1 , Martín F. 1 , and Fernández-Pachón M.S. 1 

1 Universidad Pablo de Olavide (UPO), Biología Molecular e Ingeniería Bioquímica. Área de Nutrición y Bromatología, Spain; and 

2 Instituto de la Grasa (CSIC), Biotecnología de Alimentos, Spain. icergar@upo.es 

Numerous epidemiological and intervention studies have shown an inverse association between consumption 

of fruits and vegetables and mortality from cardiovascular diseases and Cancer. Antioxidant compounds in these 

foods are responsible for these beneficial effects on health. Orange juice is known to be rich source vitamin C, 

carotenoids and flavonoids. On the other hand, numerous studies have shown the direct relationship between 

moderate alcohol consumption and a decrease in the risk of coronary heart diseases. Both effects could join in a 

novel drink created by alcoholic fermentation of orange juice. The objective of the present study is to analyze the 

effect of fermentation process on antioxidant content of orange juice. The new orange drink is produced from 

commercial orange juice by a controlled alcoholic fermentation process (20 ºC–15 days). Collection of samples 

was made daily during the fermentation. Samples were processed to determine total flavonoids content, 

ascorbic acid content, total carotenoids content and antioxidant activity using ABTS and DPPH assays. The 

results show that total flavonoids content significantly increase with the fermentation process (day 0 versus day 

15). Ascorbic acid and total carotenoids content did not undergo significant variations throughout this process. 

ABTS and DPPH values on day 15 of fermentation are similar to those of the orange juice (day 0). The alcoholic 

fermentation of the orange juice produces a drink with similar ascorbic acid, total carotenoids content and 

antioxidant activity to the substrate. However, a significant increase in total flavonoids content was observed. 

They are necessary intervention studies to evaluate the potential healthy effect of the new orange drink. 

S21P15 

Study on microwave sterilization characteristics of NFC orange juice 

Wang H., Ma Y.Q., and Wu H.J . 

Citrus Research Institute, SouthWest University, Chinese Academy of Agricultural Sciences (CRI), Citrus Research Institute, China. 

wanghua40@126.com;myaya211@163.com 

The effects of microwave sterilization on total number of colonies, yeast, mold and Escherichia coli in orange 

juice were investigated. The optimum conditions of microwave sterilization by the orthogonal test were 

determined as: sterilization time of 50 s, microwave power of 800W and orange juice volume of 50 mL. The 

results of the analysis of variance showed that the effects of sterilization time, microwave power and orange 

juice volume on sterilization rate are significant (p

S21 

of Agriculture for agricultural technology research system, we are carrying out research and development of 

automated, labor-saving and comprehensive utilization machinery to solve problem in Chinese citrus canned 

industry. The machinery includes automated peeling, segment defect detector, segment filling machine, cyst 

lossless pump systems, peel layer separator and low bubble filling equipment for citrus thick drinks. 

S21P17 

Extension of the project for obtaining bioethanol from citrus waste 

Conesa C., Fito P., and Fito P.J. 

Instituto Universitario de Ingeniería de Alimentos para el Desarrollo (IuIAD), Universidad Politécnica de Valencia (UPV), Spain. 

clcodo@etsia.upv.es 

The production of citrus fruit in Spain generates more than 0.5 million tons of waste. This is mainly due 

to rejects when packing fresh fruit, withdrawing fruit under agricultural policies and the waste generated 

by processing industries. That is the reason why an important challenge for the citrus sector is the use of 

this waste to unlock its economic value and eliminate the environmental problems that it may generate. 

The Instituto de Ingeniería de Alimentos para el Desarrollo (IIAD) at the Universidad Politécnica de Valencia 

(UPV) has developed a system for reusing waste from citrus production and processing to make bioethanol 

and high value-added niche products such as essential oils. The purpose of this study was to find the best 

sites for obtaining bioethanol from citrus waste. This meant beginning with the world’s largest citrus fruit 

producers and then calculating the waste produced by rejects, withdrawals and processing industry waste. 

The fermentable sugar content of the waste was determined and the countries where it would be feasible to 

introduce technology similar to that developed by the IIAD in Spain were identified. The candidate countries 

were Brazil, the USA, China, Mexico and Italy. 

S21P18 

Sensory analysis as an instrument for colour measurement in satsuma and ‘Nova’ mandarin fruits 

Bello F., Vázquez D., Almirón N., Meier G., and Cocco M. 

Instituto Nacional de Tecnología Agropecuaria (I.N.T.A.), Argentina. fbello@correo.inta.gov.ar 

Colour index (CI) of early maturing citrus fruits is a parameter for correct fruit degreenig process. For this 

reason the objective of this study was to develop a colour card for satsuma and ‘Nova’ mandarins fruits and 

analyze the relationship of sensory panel assesses with the measuring instrument. Fruits of both varieties 

were classified and selected to take pictures with different colour indexes using the range of -24 to 7 for 

satsuma and -21 to 10 for ‘Nova’. Charts were developed with 25 cm 2 and 100 cm 2 size photos for satsuma 

and ‘Nova’ respectively. The IC was determined as the average of 4 measurements in the middle of 25 fruits 

per variety with Minolta CR 300. Mandarins were then presented to 12 judges to indicate the IC using the 

charts. Correlation analysis was used for the relationship between values indicated by the judges and the 

colorimeter measurements. Satsuma card was r = 0.982 and r = 0.978 for ‘Nova’. The high correlation between 

colour index values measured by instrumental and sensory analysis indicates that these cards are useful and 

accurate for measuring colour in satsuma and ‘Nova’ mandarin fruits. 

S21P19 

Discrimination of three Citrus paradisi cultivars by electronic nose. 

Guarrasi V. 1 , Bernik D. 2 , Bulone D. 3 , San Biagio P. L. 3 , Germanà M. A. 1 , and Negri R. M. 2 

1 Dip. DEMETRA, Università degli Studi di Palermo, Facoltà di Agraria, Viale delle Scienze 11, 90128, Palermo, Italy; 2 Departamento 

de Quı́mica Inorgánica, Analı́tica y Quı́mica Fı́sica, Facultad de Ciencias Exactas y Naturales, Instituto de Quı́mica Fı́sica de Materiales, 

Ambiente y Energıá, Universidad de Buenos Aires, Ciudad Universitaria (INQUIMAE), Buenos Aires, Argentina; and 3 Istituto di BioFisica, 

Consiglio Nazionale delle Ricerche, Via La Malfa 153, 90146, Palermo, Italy. valeria.guarrasi@pa.ibf.cnr.it 

In this work the aromatic pattern of grapefruit (Citrus paradisi) juices has been evaluated by an electronic 

nose (e-nose) device, developed at the University of Buenos Aires. The core of this device is an array of 

11 nonspecific metal oxide semiconductor (MOS) sensors, capable of changing their electrical conductivity 


when exposed to the aroma. A non-supervised multivariate data analysis, the principal component analysis 

(PCA), was applied to data derived from sensor’s responses. The fresh hand-squeezed juices of three different 

grapefruit cultivars grown in Argentina have been analyzed (two white pulp grapefruit cultivars: ‘Marsh 

Seedless’ and ‘Thompson’, and a pigmented pulp cultivar: ‘Star Ruby’). The effect of the storage time on the 

aroma has been also taken into account by storing the fruits at room temperature for 10 days. The results 

show the capability of the e-nose to distinguish the aroma of juices of different grapefruit cultivars and, also, 

to detect the differences of juice aroma extracted from fruits stored for many days. The characteristics of 

grapefruit juice as flavor and smell are extremely important in conferring value to the product. It is possible to 

conclude that the e-nose can be successfully used both in the storage industries to monitor the fruits shelf-life 

and in the processing industries to control the product quality. 

S21P20 

Effect of several clay content in chitosan-clay nanocomposite coating on chemical and 

mechanical properties of orange fruit comparison with conventional coating during storage 

Torabi A.R. 1 , Hashemi S.J 1 , and Hashemi Z.S. 2 

1 Sari Agricultural Sciences & Natural Resources University, Biosystem and Agricultural Machinery Eng, Iran; and 2 Khouzestan 

Agriculture & Natural Resources University, Agricultural Engineering Faculty, Iran. fatemeh_hashemi48@yahoo.com 

Water loss and respiration of citrus fruits can be reduced using Nano-composite coatings in combination 

with nano-clay and natural biopolymer during storage. To determine the effect of these coatings on the 

quality of orange fruits during storage, a study was conducted in the Ramsar county of Iran in 2012 using 

a factorial complete randomized design with 8 and 4 replications for chemical and mechanical properties, 

respectively. Coating conditions were: without coating, conventional coating and nanocomposit coating with 

1, 2 or 3 percent of clay content. Storage periods were: first day, 40, 80 and 120 days. Results showed that 

differences of the weight loss, peel moisture, TA, TSS, TSS/TA and pH of fruits were in the range of 3.98% 

12.02%, 70.43-77.66, 1.01-1.51, 9.54-11.54, 6.35-11.13, 3.06-3.42 and 2-2.34 per treatment, respectively The 

mechanical properties, namely bioyield point, firmness, cutting force and fruits punch were in the range of 

153.75-240.56, 47.55-52.73, 21.25-69.44 and 13.46-20.23, respectively. Values were found to be significant 

for different coatings and storage days. These findings suggest that the chitosan-clay nanocomposite coatings 

displays a good potential for use in citrus coating intended for preserving the natural qualities of fresh and 

maintaining the marketability of the fruits during storage. 

S21P21 

Reducing decay and physiological disorders in oranges stored at suboptimal temperature by 

combined treatments 

Artes Calero F., Velázquez P., and Artés Hernández F. 

Universidad Politécnica de Cartagena (UPCT), Postharvest and Refrigeration Group, Spain. fr.artes@upct.es 

The consumer’s concern for chemical residues is raising the option of physical methods to control decay and 

physiological disorders in citrus. Middle-late season ‘Navelate’ oranges were stored for 7 weeks at 2ºC and 90- 

95 % RH plus 1 week at 20 ºC as shelf-life. Before storage fruit were subjected to several treatments, combined 

or not with 1 g/L of thiabendazole (TBZ): conditioning in air for 3 days at 36ºC, dipping for 2 min in water at 

53ºC (HW) or individually wrapping in polyvinyl chloride. Also an intermittent fruit warming for 1 day at 20 ºC 

after every week at 2ºC (IW) was applied. No detrimental effect on quality attributes was detected. After of 

cold storage slight weight losses were reached, whereas neither decay nor cracking occurred. All treatments 

were very effective in reducing chilling injuries (CI) during storage (particularly HW TBZ wrapping, and IW). 

After shelf-life, weight losses and CI increased while decay and cracking developed. In control 27.62% decayed 

and 25.1% suffered CI (pitting and rind scald). Curing in air was the only treatment that increased cracking 

(5.5%) and decay (5.5%). Despite the low dose, TBZ prevented decay (1.36%) and reduced CI (12.53%). HW 

alone strongly reduced CI (5.5%) and when combined with TBZ or wrapping a synergistic effect was found. 

TBZ IW avoided decay and CI. After shelf-life no differences in total losses (between 3.94 and 5.39%) among 

TBZ wrapping, HW TBZ, HW TBZ wrapping, and IW TBZ were found. 


S21

Session 22 

CITRUS ECONOMICS AND TRADE 

S22

S22O01 

The development of citrus industry in China during the last decade 

Deng X.X. 


xxdeng@mail.hzau.edu.cn 

Citrus industry developed very quickly during the last decade in China. The total production increased from 

8.78 MMT (million metric tons) in 2000 to 26.45 MMT in 2010; during the same period, the import and export 

volume reached 105.2 and 931.6 thousand tons respectively. The distribution and the variety structure 

also changed. The scattering citrus production over the southern provinces has been concentrated to the 

advantageous areas and formed 4 dominant belts. More sweet oranges are grown and their proportion 

increased quickly even though mandarin still accounts for two thirds of total citrus acreage. Among the 

new plantation of sweet oranges, navel oranges are the main types for the newly developed orchards. It 

is remarkable that the exploring of late harvest mandarin of local varieties including ‘Shatangju’, ‘Nianju’, 

etc., has extended the fresh market supply. The promotion of late varieties, coupling with the extension of 

late harvest technology in the areas without frost in the winter, has efficiently improved the fresh market. 

More packinghouse and packing lines have been invested, especially in the navel orange producing areas. 

Unfortunately, the orange juice production in China is still a short leg. Huanglongbing, an old disease in 

south part of China, has been a problem for Chinese citrus industry. However, there are also areas with 

good control of this disease since the integrating protocol has been adopted efficiently. Chinese citrus 

industry is encountering the challenge of quickly increasing labor cost and the lack of young workforce. 

A national system for citrus under the CARS (China Agricultural Research System) project sponsored by 

the central government was set up in 2008. A total of 24 scientists have been stably financial-sported and 

26 stations in the main producing areas have been set up by the CARS, aiming at germplasm exploring, 

new variety development, cultural practices, post-harvest and processing, mechanization and economy of 

citrus. 

S22O02 

Risk assessment of citrus yield based on yield minus deviate index and risk probability 

Huang S. 

Citrus Research Institute of Chinese Academy of Agricultural Science and School of Economics & Management of Southwest University; 

(CRIC), China. huangsen01@sina.com 

Using the citrus yield minus deviate index and citrus risk probability, the citrus yield risk of the whole nation 

of China, Zhejiang province, Jiangxi province, Hunan province and Chongqing municipality were evaluated. 

The citrus yield minus deviate index showed the deviate trend on citrus yield, caused by harmful environment 

conditions, such as bad climate and diseases, etc. The citrus risk probabilities represent the frequency of the 

citrus yield minus deviate trend. The results demonstrated that the order of citrus yield minus deviate index, 

from high to low were Zhejiang, Hunan, Jiangxi, Chongqing and the whole nation of China. The study also 

indicated that citrus risk probability of Hunan was the highest and Chongqing was the lowest. 

S22O03 

Recent trends of the citrus industry in Chile 

Ortúzar J.E., and Valenzuela M. 

Chilean Citrus Committee, Chile. jortuzar@agricom.cl 

The Chilean Citrus industry has undergone a major transformation over the last 15 years. A shift from a 

domestic to an export market oriented industry encouraged a wide renovation of plantings, a significant 

change of production and postharvest practices and a steady improvement of fruit quality. Total planted 

area, currently estimated at 19,000 ha, has not increased significantly. Orange is the main species with 

8,000 ha, followed by lemon with 7,090 ha and easy peelers with nearly 4,000 ha. Navel oranges and easy 

peelers exports grow steadily as new plantings come into bearing, while lemon plantings and exports have 


S22

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slowed down. USA is currently the main market, followed by Japan. Citrus exports in 2011 to all markets 

reached 155,000 T, valued at US$ 138 million FOB. Main varieties of orange are ‘Lane Late’, ‘Fukumoto’ and 

‘Washington’ Navel budded on ‘Swingle’, ‘C-35’, ‘Carrizo’ and ‘Rubidoux’ trifoliate rootstocks. Main mandarin 

varieties are ‘Clemenules’, ‘Orogrande’ and ‘W. Murcott’, mainly budded on ‘Carrizo’, ‘C-35’ and ‘Swingle’. 

Main lemons varieties are ‘Eureka’, ‘Fino 49’ and ‘Messina’, mostly budded on Citrus macrophylla. The export 

industry recently formed the Chilean Citrus Committee to address more decidedly market access, promotion 

and research efforts. Nonetheless the positive achievements, the industry faces several challenges due to 

increasing production costs caused by the strengthening of the Chilean peso, higher energy cost and labor 

shortage and by the impact of freezes and drought in some areas. 

S22O04 

A critical economic analysis of advanced citrus production systems (ACPS) 

Roka F.M. 

University of Florida (UF), Southwest Research and Education Center, USA. fmroka@ufl.edu 

Advanced citrus production systems (ACPS), as practiced by growers in Spain, South Africa, and Australia, 

combine higher density tree planting with intensive nutrient and water management. Many Florida citrus 

growers are looking carefully at these systems as a strategy to effectively deal with Huanglongbing (HLB), 

rising costs of fertilizer and crop protection materials, as well as increasing land prices arising from urban 

development pressures. This paper presents an ACPS enterprise budget for sweet oranges planted on the 

flatwood soils of Florida. Citrus planted on Florida flatwood soils require raised beds and swales to handle 

water drainage during the rainy season (June – September). The budget outlines irrigation requirements with 

and without freeze protection, additional equipment to handle computerized irrigation scheduling, costs to 

reconfigure the planting beds for higher density trees, as well as the increased number of trees planted per 

hectare. Available yield data from higher density plantings are compared against the economic thresholds of 

ACPS. 

S22O05 

Spanish citrus cooperatives: keys to success and challenges for the future 

Meliá Martí E., Server Izquierdo R.J., and Lajara-Camilleri N. 

Centro de Investigación en Gestión de Empresas (CEGEA), Universitat Politècnica de València, Spain. nalade@cegea.upv.es 

Cooperatives are one of the most significant elements in the production and marketing of food products 

in Spain, as in other European countries. Not surprisingly, according to data from 2008, in Spain there are 

currently 3,989 agricultural cooperatives that bring together 972,380 members and provide 94,156 direct 

jobs with total revenue of €18,889 million (CCAE, 2.010). Their role in the food value chain is indisputable 

and they have come to control most of the market share in many products such as tobacco industry (100%), 

grape must (80%), olive oil (75%), wine (70%), rice production (60%) and a 45% in citrus, milk and nuts. 

To a lesser extent they are present in the production of table olives, fruits, sheep and goat meat, cereals, 

oilseeds and cotton in which they account for 35% (CCAE, 2.010). Additionally cooperatives have emerged as 

the driving forces of the territory, allowing the adoption of technology, leading the internationalization and 

developing important management tasks. In recent decades, its role has been intensified by globalization, 

ongoing regulatory requirements and the need for diversification that has emerged in rural settings in order 

to keep the population. This paper develops a study of agrifood cooperatives in Spain and more specifically of 

citrus ones. Structural problems of holdings (small holdings in certain crops) have marked the need to group 

farmers in order to concentrate supply, internationalize, concentrate financial resources to promote joint 

R&D and ultimately to improve profitability. Through it, strengths of this kind of company are identified, as 

main responsible characteristics for the preponderant place that these entities have achieved in the sector. 

Moreover, the challenges that cooperatives are facing to ensure continuity in the current economic context 

are also discussed. 


S22O06 

Evolution of development models for Italian organic citrus growing: economic and 

environmental aspects 

Scuderi A., and D’Amico M. 

Department of Agri-food and environmental systems and management (DIGESA), Faculty of Agriculture, University of Catania, Italy. 

alessandro.scuderi@unict.it 

Italian organic farming has been experiencing an intense development phase in the last ten years, arising the 

interest at economic, political and social level for its general effects on the population. In order to design the 

development models and understand the current differences between organic and traditional growing, the 

present study chooses the comparative analysis of homogeneous models. Indeed, the studies concerning the 

technical-economic analysis have revealed the existence of different methodologies. Method references, in 

such a context, are those to the studies of Spugnoli (1985), Biondi (1987) and Pimentel (1980), who analyzed 

the traditional farming and outlined a detailed picture of the energetic analysis by defining the conversion 

values of the main factors involved in the production process. The complexity of such analysis grew directly 

proportional with that of the production process of each single company, and the variety of indicators of the 

energy demand of the two production methods according to a structure based on the main inputs introduced 

in the production process, by adopting Gigajoule (GJ)-measured data for surface units and Megajoule (MJ)measured 

data for product units. The analysis carried out in 2010 considered 80 organic farms above all 

Italian orange and lemon growing out of a sample of 20 organic farms and 20 traditional ones. Results showed 

interesting differences between organic and traditional methods. Such differences should become the starting 

point to exalt the plus of organic farming for consumers, politicians, business men, along the sector and in 

general within society, to offer a different role than today’s organic farming. 

S22O07 

The importance of Research and Technical services in the recent growth of the southern African 

citrus export industry 

Hattingh V. 

Citrus Research International (CRI), South Africa. vh@cri.co.za 

The southern African citrus industry’s production and export statistics for the past 10 years were reviewed as 

an indicator of the longer term strategic direction it has pursued. It was evident that the climatically diverse 

range of production regions within the industry, spanning South Africa, Swaziland and Zimbabwe, was 

advantageous in enabling production of a wide range of cultivars across a broad production window of time. 

The long distance from lucrative world markets was clearly a disadvantage in that the prolonged shipping 

made the supply chain expensive, requiring high quality standards and sales values to remain profitable. A 

long history of industry commitment to supporting Research and Technical support services was linked to 

the specific challenges that this posed to realising the value of the industry’s production advantages. This 

link was further evident in the industry’s active pursuit of access to new markets and the retention of access 

to existing markets, especially in light of an increase in attention to international Sanitary and Phytosanitary 

trade regulations. The success of the industry’s focus on Research and Technical support was reflected in the 

120% increase in export volumes over the past 15 years, with a 55% growth over the past 10 years and an 

increase in the gross export Rand returns of approximately 160% over the past 10 years. 

S22P01 

Trends in varietal composition in Spanish citrus-growing and underlying variables 

Caballero P. 1 , Fernandez-Zamudio M.A. 1 , Carmona B. 1 , Alcon F. 2 , and de Miguel Gomez M.D. 2 

1 Instituto Valenciano de Investigaciones Agrarias (Ivia), Economia y Sociologia Agrarias, Spain; and 2 Universidad Politecnica De 

Cartagena (UPCT), Economia De La Empresa, Spain. md.miguel@upct.es 

Citrus varieties as a whole must meet two basic conditions for fresh consumption: i) they should cover the 

widest possible commercial calendar, and ii) allow continuous adaptation to consumer preferences. For citrus 


S22

S22 

growers, this requires permanent technology up-dates and changes in variety grown, driven by income-risk 

criteria, as well as technical and commercial experience. The duration of an investment depends on the 

agronomic performance of the variety or its commercial life, which can sometimes be shortened due to 

lack of consumer acceptance. The survival of a variety depends on many variables: technical, quality, and 

competitiveness of the variety. Spanish citrus production falls into five main groups of varieties: lemons 

(13%), clementines (25%), mandarin hybrids (9.5%), navels (32%) and common sweet oranges (12%). The 

most productive varieties are: ‘Fino’, ‘Navelina’, ‘Clemenules’, ‘Lane Late’ and ‘Valencia’. Regarding changes 

in varietal composition of interest, the introduction of new varieties or clones of the ‘Clemenules’ groups 

(‘Orogrande’, ‘Nulessin’), Navel (‘Powell’, ‘Rohde’, ‘Barnfield’) and ‘Valencia’ (‘Barberina’, ‘Midknight’, ‘V. 

Late Frost’ and ‘Delta Seedless’) is noteworthy. There is constant pressure to supply new varieties of early 

clementines, whose survival is usually short. Currently, mandarin hybrids represent one group with potential 

to expand. 

S22P02 

Evolution of the international citrus trade in the Valencian region. 

Aznar Puente J.L., García Martínez G., Silvestre Esteve E., and Orea Vega G. 

Universitat Politécnica De València (UPV), Economics and Social Sciences, Spain. ensiles@esp.upv.es 

The citrus production in the Valencian Region, is clearly oriented to the final consumer and presents a 

consolidated export tradition. Spain has become for years the leader in the worldwide citrus market, and 

the Valencian Region represents the 75% of the total Spanish exports. Consumers are increasingly more 

concerned about environment issues. They constitute along with prices the two most important variables in 

their decision process. Citrus growing and especially its transportation produce relevant energy consumption 

and greenhouse gas emissions. Transportation is a factor that directly affects the price of the goods and could 

become critical for, in certain cases, penalizing the product. For citrus companies, the energy consumption in 

transport and the generation of greenhouse gas emissions will vary depending on the mode of transport used. 

Therefore, in order to preserve their competitiveness, not only it is necessary that companies know which 

transportation mode is more efficient, but also which one is less aggressive with the environment. According 

to the above, this paper develops a model that calculates the absorption / emission of CO 2 derived from the 

citrus cultivation and the citrus export by land transport modes. The objectives pursued are as the following: 

1) To identify the main export trade flows of Spain and the Valencian Region, and the transportation needs 

that they generate; 2) To determine the current transport mode framework in the citrus export, by defining 

the use of each type of transport mode towards the most significant country destinations; 3) To calculate the 

CO2 balance emission / absortion associated to the citrus crop growing procedures and the balance caused 

by the international transportation of the Valencian citrus products; and 4) To compare and calculate the 

economic costs linked to the land transportation modes to the main foreign markets, that the Valencian citrus 

export companies currently face. 

S22P03 

The citrus chain in Entre Rios: characterization and economic impact of some technologies to 

increase competitiveness and equity 

Vera L.M.V., Díaz Vélez R.D.V., Banfi G.B., Garrán S.M., and Gómez C.G. 

Instituto Nacional de Tecnología Agropecuaria (INTA), Experimental Concordia. Entre Ríos, Argentina. luismariavera@gmail.com 

Citrus chain in Entre Rios, include 42,000 ha of citrus, principally with orange and mandarin, and nearly 

1,800 growers. The average area per grower is nearly to 24 ha, but the incidence of the small fields, the 

modal area is between 15 and 20 ha. Then the technology may be able to resolve the trouble of this kind of 

productive structure. The high density plantation and the precision citriculture technology make an interesting 

contribution on this way. This work study the economic aspect of this technology proposal, related with the 

costs, income distribution, resumed in economics and financial indices, in comparation with the traditional 

density and management. The experience in the Experimental Concordia, indicate that the cost can be nearly 

to the traditional working form, but the productivity and quality can increase significantly. 


S22P04 

The experience of the Entre Ríos Citrus Board, and its contribution to the citrus industry. 

Vera L.M.V. 

Instituto Nacional de Tecnología Agropecuaria (I.N.T.A.), Experimental Concordia. Concordia City, Entre Ríos, Province, Argentina. 

luismariavera@gmail.com 

Concordia, in Entre Ríos province, became in ’60’ decade, the National Capital of Citrus in Argentina. That 

is because the important growth of citrus area and production in the north east of the province since 1945 

to this time, and became the principal citrus region of the country. The production was oriented to supply 

fresh fruit to the local market. But citrus industries for making juice, needed to regulate the quality and 

commerce of fresh fruit. In 1962 a juice factory was build, called Las Tejas in 1962. It was mixed (public – 

private) company thought for the small and medium growers. In 1965 and 1967, the hardest frosts, until then, 

took place. Las Tejas preserved the incomes of the small growers, but the sustainability of the system was not 

insured. That’s why, in 1967, the Entre Ríos Citrus Board (ECB) was created to complete the system. The board 

had two principal objectives, one was to improve all regional citrus industry, and the other to regulate and 

improve the commerce and the industrialization. The contributions in both directions were very important. 

But ECB was dissolved by the State in 1982, basically because of the implementation of a neoliberal vision. 

Similar process occurred in other citrus region. Now in 2012, the other hardest frozen has taken place, and 

other similar troubles are also associated, and organizations like ECB seem to be necessary. This work rescues 

the experience of ECB, in this sense. 

S22P05 

Overview of organic citrus production in the Algarve (Portugal) 

Reis D. 1 , Fernandes M.M. 2 , Marreiros A. 2 , Mourão I. 3 , and Duarte A. 4 

1 Instituto Politécnico de Viana do Castelo (IPVC), Escola Superior Agrária de Ponte de Lima, Portugal; 2 Direcção Regional de Agricultura 

e Pescas do Algarve (DRAPALG), Portugal; 3 Centro de Investigação de Montanha/Instituto Politécnico de Viana do Castelo (CIMO/ 

IPVC), Escola Superior Agrária de Ponte de Lima, Portugal; and 4 Institute of Mediterranean Agricultural and Environmental Sciences - 

University of Algarve (ICAAM/UAlg), Faculty of Sciences and Technology, Portugal. dhcreis@gmail.com 

The citrus industry in the Algarve holds a leading position in the overall national fruit production. However, only 

a few citrus producers certify their production as organic farming, which should be increased if we consider the 

advantages of organic production compared to the conventional systems. From a technical point of view, the 

regulations of organic citrus fruit production can be applied straightforwardly. Although the control of some 

pests could be difficult, particularly Ceratitis capitata and scale insects, usually they do not cause major problems 

when organic pest control methods are used. Moreover, yield can be close to that obtained in conventional 

agriculture. Nowadays, only few farms produce organic citrus fruits in the Algarve and the mean area of citrus 

orchards is very small (2.3 ha per farm). In addition, some organic farmers have neglected crop management 

in their citrus orchards. The basis of their low incentive is the relative low prices paid to citrus fruits, as well 

as the payment schedule, since payments often are performed six months after crop trade, namely through 

supermarket chains. This has led to a replacement of the citrus production in favour of other crops or to other 

more rewarding farm activities. If prices go up and / or payment terms become more favourable, Portuguese 

organic citrus production could increase significantly in a short period of time. 

S22P06 

Citrus and pomegranate cultivation: concurrence vs competition in eastern Spain 

Melian Navarro A. 1 , de Miguel Gomez M.D. 2 , and Fernandez-Zamudio M.A. 3 

1 Universidad Miguel Hernandez (UMH), Economia Agroambiental, Spain; 2 Universidad Politecnica de Cartagena (UPCT), Economia de 

la Empresa, Spain; and 3 Instituto Valenciano de Investigaciones Agrarias (IVIA), Horticultura, Spain. md.miguel@upct.es 

Citrus growing, traditionally associated with Spanish Mediterranean agriculture, is particularly sensitive to 

water allocation fluctuations. In this area the structural water resource deficits, as well as the gradual decline 

in citrus prices received by farmers, have promoted the co-plantation of other crops that are more resistant 

to water shortage, such as pomegranates, which have been grown in eastern Spain for decades. At present, 


S22

S22 

demand is growing due to knowledge of pomegranates’ nutritional benefits and functional food qualities. In 

this paper, we analyze the different techno-economic aspects of citrus and pomegranate growing, as they 

pose ever increasing competition to each other. Comparison of these two crops begins with an assessment, 

from the farm economy perspective, of the main results published in the scientific literature on regulated 

deficit irrigation, this being one of the most up-to-date techniques used to address water shortage not clear. 

Also, the study analyzes the trend in prices received by farmers for the ‘Lane Late’ orange, ‘Clemenules’ 

mandarin, and for the two main Spanish varieties of pomegranate. The economic outlook expected from 

these two crops is rounded off by an analysis of investments, which shows the profitability of individual farms. 

S22P07 

PDO and PGI citrus productions: state of the art and perspectives 

Scuderi A . , and Pecorino B. 

Faculty of Agriculture, University of Catania, (DIGESA), Department of agri-food and environmental systems and management, Italy. 

alessandro.scuderi@unict.it 

Within the field of agrifood and certified hortofruit productions, citrus fruits play a very important role, 

especially for Italy. In fact, 12 appellations out of the 19 ones worldwide recognized have Italian origin. In 

fact, they have become a significant and strategic sector of the national economy, in particular for the South, 

which, nevertheless, in the last times is experiencing a severe crisis, with growing loss of market shares and 

profitability for producers. Therefore, the need of an intervention is pressing now, at structural, economic and 

financial level, to overcome it. Besides, improving production efficacy and farmers’ profits, special attention is 

to be paid to the economic development of the entire production system, focusing on the concept of global 

quality. The new strategy of the modernization process of Italian citrus growing is to be based on two priority 

targets: food safety for consumer protection and enhancement of agrifood production quality. To this end this 

report analyzed, in a system perspective, the state of the art of quality productions by adopting SWOT analysis 

mode. Preferring the system approach implied an articulated group of specific targets aiming at obtaining the 

improvement of the conditions of the production phase and the market efficiency for citrus productions. 

S22P08 

Comparisons of fruits load estimation methods using geostatistical techniques 

Gimenez L.I., Cabrera Brunetti S.C., Avanza M.M., and Mazza S.M. 

Universidad Nacional del Nordeste (UNNE), Facultad de Ciencias Agrarias, Argentina. smmazza@gmail.com 

Anticipated knowledge of fruits harvest is useful to define management and marketing strategies. Prediction 

methods use objective field data by counting the fruit in the entire canopy of trees or in sections of them, 

with known volume, and then apply mathematic expressions for geometric bodies, to calculate the total 

volume. Variability in load of fruit trees occurs, in time, with alternation between years of high and low 

production, and in space, between areas of higher and lower productivity. Geostatistical techniques allow 

using spatial information for estimating variables distributed in space. This study aimed to compare methods 

for estimating fruit load in ‘Valencia late’ sweet orange quantifying the spatial dependence. Field data were 

obtained on a commercial orchard of ‘Valencia late’ sweet orange, located in Entre Rios, Argentina, during 

the seasons 2009/10 and 2010/11. Load was estimated 60 days before harvest on sample of the 6.5% of 

trees, by two methods: counting fruits in the entire canopy (TC) or into a frame of 0.5 m of side (0.125 m3) 

and applying the cone volume formula (FC); at harvest all fruit in the canopy was counted (RL). Using the 

residual sums of square as a selection criterion, mathematical models that quantify spatial dependence of 

harvested (RL) and estimated load (TC and FC) were determined. Real load adjusted to a spherical model, in 

both seasons, with ranges of spatial dependence of 20.58 m and 16.52 m and estimates of the total variance 

of 140.574 and 129.043 in seasons 2009/10 and 2010/11 respectively. In season 2009/10 predicted values 

by both methods fitted to an exponential model, with ranges of 20.82 m and 25.38 m and sills of 104.263 

and 86.022 respectively. In season 2010/11 predicted values by both methods fitted to a spherical model 

with ranges of 16.58 m and 14.62 m and sills of 69.887 and 100.426 respectively. Both methods characterize 

adequately the structure of spatial dependence but underestimate total variance. 


S22P09 

Price evolution of ‘Clemenules’ and ‘Navelina’ in Spain in the period 2007-2012 

Server Izquierdo R.J., García-Martínez G., Lajara-Camilleri N., and Orea-Vega G. 

Centro de Investigación en Gestión de Empresas (CEGEA), Universitat Politècnica de València, Spain. nalade@cegea.upv.es 

Citrus crop is strongly affected by cyclical swings in their productions. This fact, among others, is reflected in 

the evolution of prices that are received by farmers. This instability results in an uncertain income for farmers, 

being even not enough –in some cases- to cover the expenses incurred by the activity. This paper analyzes 

the evolution in the past five campaigns of the average price received by the farmer (“price in tree”) and by 

wholesalers in some of the most important citrus varieties cultivated in Spain: the clementine ‘Clemenules’ 

and the navel orange ‘Navelina’. Additionally, volumes are analyzed based on the available information on 

statistics agencies. The aim of the paper is to characterize the evolution of prices and highlight the differences 

between the agents considered, in order to be a first step in the study of supply and demand of fresh citrus 

fruit in Spain. 

S22P10 

São Francisco Valley as a new belt for the Brazilian citrus industry 

Passos O.S. 1 , Bastos D.C. 2 , Soares Filho W.S. 1 , Girardi E.A. 1 , and Leão H.C. 3 

1 Embrapa Cassava and Fruit Crops Center (Embrapa-CNPMF), NUGENE-Citros, Brazil; 2 Embrapa Semiarid Center (Embrapa-CPATSA), Fruit 

Crops, Brazil; and 3 Fischer S/A Com Ind. Agricultura (Citrosuco Fischer), Technical Department, Brazil. orlando@cnpmf.embrapa.br 

The citrus industry is one of the most relevant segments of the Brazilian agribusiness, being responsible 

for 40% of the sweet orange production and 60% of the juice processing in the World. Some factors for 

this hegemony are the adequate ecological conditions, which allow cultivation without irrigation, and huge 

land availability. Threats, however, exist especially at the core of national production, in the State of São 

Paulo. The most important bacterial and virus diseases appear with increasingly incidence and destructive 

power. The Northeast, the second national producing region seems to have the best conditions for the citrus 

industry expansion. Among potential areas, the São Francisco Valley appears as one the best options due 

to the semiarid climate, government support and tradition in the irrigated fruit production and export. The 

region, with 360,000 ha potentially irrigable, is located between 8º and 9º S and 40º to 42º W and altitude of 

300 m. The annual rainfall is less than 600 mm and the average temperature is 26.2º C, relative humidity of 

67% and solar radiation of 3,000 h/year, constituting a comparative advantage to species such as acid lime, 

lemon and grapefruit. Citrus scions and rootstocks trials have been carried out since the 90´s by Embrapa in 

cooperation with the private sector in the States of Bahia and Pernambuco, which data are presented in this 

paper, showing the potentiality of the São Francisco Valley as a new belt for the Brazilian citrus industry. 


S22

Author’s Index

A 

Abdel Fattah A. 249 

Abdelgallel A. 78 

Abe A. 111 

Aboutalebi Jahromi A. 338 

Abreu Jr. C.H. 167 

Acevedo Sánchez G. 199, 240 

Achachi A.A. 252 

Achor D.S. 201 

Acosta I. 217 

Addison P. 289 

Adediji A.O. 238 

Ademerval Garcia 5 

Adesemoye A.O. 268 

Adler C. 212 

Adorno A. 295 

Adragna V. 244 

Afechtal M. 233 

Agostini J.P. 255, 261 

Agüero J. 64,248 

Aguilar A. 281 

Aguilar-Fenollosa E. 282,291 

Aguilera-Cogley V. 266, 267 

Agustí J. 95 

Agustí M. 67, 68, 97, 

110, 332 

Agut B. 293 

Ahmad I. 184 

Ahmed Y. 268 

Ait Ben Aoumar A. 147, 148, 152 

Aka Kacar Y. 45, 47 

Akhlaghi Amiri N. 102, 103 

Aksenov A.A. 214 

Al Naasan Y. 243 

Al-Babili S. 75 

Al-Harthi S.A. 249 

Al-Sadi A.M. 214, 249 

Al-Said F.A. 214 

AL-Yahyai R.A. 214 

Alayón Luaces P. 171 

Alba L. 245, 246 

Albanese G. 237 

Albrecht U. 196, 323 

Albrigo L.G. 108, 113 

Alcayde E. 129, 160, 167 

Alcon F. 369 

Alessandro R. T. 279 

Aleza P. 14, 37, 42, 43, 

49, 63, 67, 88, 

90, 264, 313 

Alfaro C. 229, 301 

Alférez F. 137, 139, 142 

Ali W. 184 

Ali-Dinar H. 128 

Aljaleel A. 128 

Allegra M. 117, 160, 172 

Almenares G. 95, 114 

Almirón N. 362 

Alonso R. 61 

Alós E 75, 138, 345 

Alphey L. 224 

Alquézar B. 75, 76, 81 

Altieri G. 357 

Álvarez J.M. 184 

Alves G.R. 284 

Alves R.R. 181 

Aly R. 133 

Amato M. A. 200 

Ambrós S. 234, 238 

Amenta M. 353, 355, 357 

Amin G. 302 

Amin M. 152 

Amorim L. 261, 265, 266 

Amuedo S. 284 

Ancillo G. 27, 28, 31, 32, 

67, 331 

Anderson C. 185, 319, 326 

Andreazza C.S. 151 

Andujar S. 162 

Annaka A.H. 144 

Annandale J.G. 157 

Appezzato-da-Glória B. 266 

Aranguren M. 95, 114 

Arbona V. 118 

Arenas Arenas F.J. 183, 309, 310, 

329 

Arevalo H.A. 205 

Argamasilla R. 118 

Argiles R. 221 

Argolo P.S. 292 

Arimoto Y.A. 144 

Ariyoshi C. 78 

Arouri R. 222 

Arrieta M.P. 91, 92 

Arsalane N. 53, 318 

Artes Calero F. 363 

Artés Hernández F. 363 

Arzani K. 102 

Asad H.U. 152 

Asadi Kangarshahi A. 102, 103 

Asakura T. 185 

Asanzi N.M. 168 

Asíns M.J. 41 

Askari M. 302 

Askarne L. 147, 148, 152 

Aslan F. 47 

Asplanato G. 284 

Atiri G.I. 238 

Auler P.A.M. 169, 180 

Avalos Rodriguez Y. 226 

Avanza M.M. 263, 372 

Azevedo F.A. 262, 313, 314, 

315 

Aznar M. 287 

Aznar Puente J.L. 370 

Azpiazú I. 184 

B 

Baba A.B. 171 

Bachchu M.A.A. 83 

Bae H.J. 79 

Bagayogo S. 164 

Bagio T.Z. 83 

Bai X. 200 

Balal R.M. 128 

Balducchi R. 354, 346 

Balkılıç R. 57 

Ballester A.R. 133, 143, 145 

Bamouh A 170 

Banfi G.B. 370 

Bani Hashemian S.M. 234 

Bar-Joseph M. 233 

Barantin P. 51 

Barbagallo S. 157 

Barbosa J.C. 227 

Barbosa V.G. 301 

Barone F. 162 

Barreto T.P. 211 

Barry G.H. 42 

Barthe G.A. 196, 325 

Bassal M.A. 338 

Bassan M.M. 183 

Bassanezi R.B. 199, 235 

Bassi D. 33 

Bassimba D.D.M. 257, 264 

Bastianel M. 46, 52, 202, 

313, 314, 315, 

334 

Bastos D.C. 333, 373 

Bataglia O.C. 205 

Batista L. 217 

Battikhi A.M. 172 

Bayle D. 344 

Beattie A. 216 

Beattie G.A.C. 194, 279 

Becerra V. 298 


Beitia F. 228 

Belda J.E. 290 

Beldoménico H. 348 

Belkahla H. 243 

Bella P. 262 

Bellete B.S. 118 

Bello F. 359, 362 

Belmahdi I. 323 

Beloti V.H. 204, 298, 301 

Beltrà A. 289 

Beltrán Castillo A. 226 

Ben Jannet M. 228 

Ben Mimoun M. 101, 121, 124, 

251 

Ben Yahmed J. 121, 124 

Ben-Dor S. 107 

Benaouda H. 318 

Benazzouz A. 326, 328 

BenDayan C. 133, 146 

Bender G.S. 31 

Bender R.J. 48, 151 

Beniken L. 123, 124, 326, 

328 

Benismail M.C. 164, 173 

Benkirane R. 122, 123, 124 

Bennetau-Pelissero C. 345 

Bentancur O. 97 

Benyahia B.H. 122 

Benyahia H. 53, 123, 124, 

318, 326, 328 

Bérard A. 63 

Berard A.M. 345 

Beribe M.J. 187 

Bermejo A. 316 

Berná G. 361 

Bernabeu P. 287 

Bernardes L.A.S. 70 

Bernardo L 354 

Bernet G.P. 41 

Bernik D. 362 

Beroiz B. 222 

Berti L. 129 

Bertolami E. 244 

Bertolini E. 193, 234, 236, 

242, 248 

Bertomeu S. 287 

Besoain X. 270, 315 

Betancourt M. 95, 114 

Bhose Sumit 216 

Bianco C. 91 

Biasi L.A. 90 

Bidel L.P.R. 347 

Bijzet Z. 39, 41, 314 

Billot C. 63 

Biondi A. 291, 292, 295 

Birkett M.A. 287 

Biswas M.K. 317 

Bloch JR C. 211 

Boaretto A.E. 167 

Boaretto R.M. 159, 160, 167, 

168, 169 

Boava L.P. 202 

Boca R.T. 187 

Bohannon R. 200 

Boland A. 63 

Boman B. J. 172 

Bonafé C. 165, 332 

Bonato C.M. 212 

Bonatto D. 70, 117 

Boncuk M. 45, 47 

Bonesi M. 346 

Bonnart R. 27 

Bono G. 244 

Booyse M. 41 

Bordas M. 330, 331 

Bordini G.P. 298 

Borges M. 287 

Borges Soto M. 226 

Borovsky D. 279 

Borsani O. 113 

Boselli M. 146 

Botella P. 242 

Botía P. 121, 164 

Bouabid R 170 

Boubaker H. 147, 148, 152 

Boudyach E.H. 147, 148, 152 

Bouffin J. 37, 312 

Bouhlel R. 251 

Bourachde Y. 53 

Bové J.M. 13, 193 

Bowman K.D. 18, 196, 323 

Bozan O.B. 240 

Branco M. 290 

Brand G.D. 211 

Bremer Neto H. 183, 308, 317 

Bright D.B. 202 

Brito M.C.R. 143, 270 

Brito P.C.N. 143, 270 

Brlansky R.H. 201, 285 

Brodeur J. 10 

Brotons J. 317 

Brumós J. 121 

Brunel D. 63 

Bueno A.C.R. 110 

Bulone D. 362 

378 - VALENCIA CONFERENCE CENTER, 18th-23rd NOVEMBER 2012 

Burdyn L. 263, 269, 298 

Burgess L. 279 

Burns J.K. 137 

Butelli E. 75 

C 

Caballero P. 369 

Cabrera Brunetti S.C. 372 

Cação S.M.B. 78 

Cai L. 99 

Cailun J. 98, 99 

Caisley J. 177 

Calabro V. 346, 354 

Calabuig A. 294 

Calandra M. 357 

Caldeira R.E. 298 

Calderone G. 244 

Camacho H. 225, 295 

Camañes G. 122, 264 

Camargo L.E.A. 317 

Cambra M. 193, 236, 242, 

248 

Campolo O. 287 

Campos A. 349 

Campos L. 210 

Campos Rivela J.M. 289, 294, 330 

Campos-Herrera R. 277 

Camps R. 270 

Cancalon P. 40, 343 

Candresse T. 236 

Cannard M. 179 

Cano A. 242 

Cano D. 280 

Canteros B.I. 311 

Cantuarias-Avilés T. 183 

Cao H.B. 80 

Cao M.J. 236 

Cao W.Q. 318 

Caputo M.M. 308 

Carbajo M.S. 141, 148 

Carbó C. 248 

Carbonel A.A. 310 

Carbonell E.A. 41 

Carbonell J. 61 

Carbonell J.V. 344 

Cardeñosa V. 329 

Cardoso J.C. 78 

Carimi F. 89 

Carlos E.F. 78 

Carmi N. 40 

Carmona B. 369 

Carmona L. 75, 134

Carra A. 89 

Carrera R.R. 108 

Carrillo-Medrano S.H. 285 

Carrizo B. 349 

Carstens E. 259 

Carta Cerella D. 112, 244 

Caruso A. 244, 247 

Caruso M. 64, 70 

Carvalho S.A. 55, 203 

Casales F. 91 

Casilli A. 316 

Casín J.C. 217 

Castagnaro A.P. 208, 210, 212 

Castañera P. 221, 222 

Castillo M.C. 67 

Castle W.S. 39, 323, 325 

Castro L.M. 88 

Castro M. 270, 315 

Catara A. 233, 241, 244, 

262 

Catara V. 262 

Cautin R. 315 

Cavallaro A. 244 

Cavallaro G. 244 

Cave R. D. 279 

Cecon P.R. 182, 183 

Cen Y. 194, 286 

Cercós M. 95 

Cerrillo I. 361 

Cervera A. 222 

Cervera M. 76, 80 

Chabbal M.D. 171 

Chae C.W. 51, 56, 336 

Chahidi B. 50, 53, 328 

Chai L.J. 317 

Chanet A. 345 

Chauveau A. 63 

Chavarria J. 305 

Chen C. 40, 63, 200, 

201 

Chen C.L. 62 

Chen D.J. 62 

Chen G.Q. 256 

Chen H.M. 236, 249 

Chen J. 194, 286, 338, 

345 

Chen J.C. 207, 213 

Chen K.L. 51, 52, 180, 

182 

Chen L.L. 62 

Chen S.C. 79, 84 

Chen W. J. 347, 348, 349 

Chen Y.M. 198 

Cheng C.F. 80, 314 

Cheng C.Z. 337 

Cheng Y.J. 96, 139, 356 

Chermiti B. 228, 300, 301 

Chetto O. 122, 123 

Cheung W.H.K. 214 

Chiancone B. 78, 91 

Chica E.J. 113 

Chiera E. 287 

Chiesa M.A. 208, 210 

Choi I.S. 79 

Choi Y.H. 336 

Chomé P. 250 

Chun C. 99 

Chung S.J. 69 

Chunxian C. 42 

Cicala A. 95 

Cidade L.C. 65 

Cilli E.M. 211 

Çimen B. 120, 127, 327 

Cirelli G. 157 

Cocco M. 359, 362 

Cocuzza G. 233 

Coelho Filho M.A. 65, 117, 118 

Colás C. 229 

Coletta Filho H.D. 43, 202, 203, 

204 

Collado C. 242 

Collazo C. 271 

Colmenero J.M. 121 

Colmenero-Flores J.M. 61 

Colomer M. 193 

Combrink N.K. 39, 41, 314 

Conejero V. 210 

Conesa A. 61, 126, 317 

Conesa C. 362 

Conesa E. 136, 358 

Connolly K. 157, 179 

Consoli S. 157, 158 

Conti F. 244, 291,296 

Continella A. 158, 163 

Coqueiro D.S.O. 212 

Corazza M.J. 241 

Corno G. 244 

Correia P.J. 329 

Costa J. 32 

Costa M.G.C. 65, 117, 118 

Costa N. 185, 247, 326 

Costantino G. 31, 32, 50, 63, 

119, 124 

Coto O. 271 

Couso-Ferrer F. 222 

Creek A. 305 

Creste A. 205 

Cristofani-Yaly M. 45, 52, 202, 

313, 314, 334 

Croce Filho J. 46 

Cronje P.J.R. 136, 141 

Cubero J. 197, 209 

Cuenca J. 37, 42, 43, 49, 

63, 264, 313, 

358 

Cueto J.C. 164, 188 

Cunha R.A. 301 

Cunha T. 150 

Cunningham N.M. 135 

Cupane M. 359 

Curk F. 28, 31, 32, 44 

Cutuli A. 244 

D 

D’Amico M. 369 

D’Anna R. 244 

D’Onghia A.M. 89, 187, 233, 

241, 243, 249, 

268 

Daden M. 233, 244 

Dai S. 244 

Dai S.M. 65, 87, 198 

Dal B. 57, 141 

Dambier D. 37, 50, 51, 

122 

Dao H.T. 279 

Daraei A. 142 

Daraei-Garmakhany A. 140 

Davino S. 237, 244 

Davis C.E. 214 

de Bona C.M. 90 

de Cristobal R.E. 212 

de Francesco A. 247 

de la Fuente B. 133 

de Miguel A. 165, 332 

de Miguel Gomez M.D. 369, 371 

de Miranda M.P 205 

de Negri J.D. 313 

de Oliveira T.M. 65 

de Ollas C. 76, 118 

de Pardo R. 188 

de Ramón-Carbonell M. 133, 145 

de Souza A.A. 209 

Debreczeni D. 237 

Decorzant E. 316 

Defez R. 91 

Deidda B. 111 

del Campo R.d.C. 143, 151 


del Pino A. 330, 333 

Del Río J.A. 145 

Delledonne M. 117 

Delort E. 316 

Demirbas H. 288 

Deng X. 194, 286 

Deng X.L. 207 

Deng X.X. 62, 75, 78, 80, 

85, 96, 109, 

139, 317,347, 

356, 367 

Deng Z. 153, 244 

Deng Z.N. 65, 66, 77, 87, 

198 

Dessena L. 111 

Dewdney M.M. 255, 265, 270 

Dewi P.S. 48 

Di Leo A. 328 

Di Natale A. 244 

Di Renzo G.C. 357 

Di Sanzo G. 346, 354 

Díaz L. 145 

Díaz L.D. 143, 151 

Díaz P. 113 

Díaz Vélez R.D.V. 370 

Diaz-Candelas C.C. 137 

Ding F. 49 

Diniz A.J.F. 284 

Distefano G. 47, 64, 70, 95, 

138, 153 

Djelouah K. 89, 233, 241, 

243, 249 

do Carmo-Uehara A. 204 

Doddapaneni H. 213 

Domingo C. 95 

Dominguez M. 229 

Domínguez Monge S. 199, 240 

Dongiovanni C. 187 

Donmez D. 45 

Donovan N. 216, 324 

Dopazo J. 61 

Dorjee D. 216 

dos Santos L.C. 151 

dos Santos R.P. 48 

Drenth A. 263 

Drew R.A.I. 227 

Driggers R. 195 

Droby S. 133, 146 

Du Preez D. 281 

Duale C. 344 

Duan Y.P. 193, 195 

Duarte A. 185, 306, 329, 

371 

Dubray C. 344 

Dummel D.M. 255 

Duncan L.W. 277 

Durán G.D. 164 

Durán-Martínez C.M. 109 

Duran-Vila N. 234, 248, 251 

Durand M.V.S. 347 

Dutra-Souza J. 45 

Dutt M. 196 

Duval M.F. 33 

Ebert T.A. 278, 285 

E 

Ebrahimi Y. 130 

Economopoulos A. 224 

Egozi Y. 179 

Eisa A.M. 120 

Ekesi S. 223, 283 

El Guilli M. 170, 323 

El-Borai F.E. 277 

El-Fadl A. 164, 173 

El-Otmani M. 164, 173 

El-Shazly S. M. 120, 169, 170 

El-Shimy H. 268 

Ellstrand N. 30 

Endo T. 44, 85, 108 

Enrique R. 208 

Epifani R. 160 

Erasmus A. 148, 152 

Ercisli S. 357 

Ercişli S. 58 

Erkilic L.B. 288 

Eryılmaz Z. 57, 58 

Escalon A. 197 

Escudero B. 361 

Eskalen A. 268 

Espino M. 98 

Espinoza V. 119 

Espinoza-Núñez E. 183 

Essajid A. 328 

Estornell L.H. 95 

Eti S. 47 

Etxeberria E. 201 

Ezra D. 264 

F 

Fa X. 98, 99 

Faber B.A. 108 

Fabroni S. 353, 355, 357 

Fachini E. 162, 166 

Fadel A.L. 308, 334 

Fadini M. 315 


Fadli A. 122, 123, 124 

Faerron P. 295 

Fagoaga C. 77, 84, 234, 

235 

Fainzack M. 179, 307 

Falcao A.O. 211 

Falchetto M. 222 

Falivene S 157, 161, 179 

Fallanaj F. 136, 146 

Fan J. 201 

Fancelli M. 287 

Fanciullino A.L. 96, 347 

Farias M.F. 141, 148 

Farina V. 162 

Fascetto G.T. 244 

Fasiolo C. 97, 98 

Fassini C.G. 203 

Favaro M.A. 208 

Febres V.J. 82, 86 

Federici C.T. 63, 333 

Federico R. 244 

Felício M.S. 78 

Felipe R.T.A. 193 

Felippe M.R. 204, 205, 278, 

298 

Felippe N. 296 

Feng D. 28, 135 

Fereres A. 278 

Fernandes K.A. 52 

Fernandes M.M. 185, 371 

Fernández-Crespo E. 122, 264 

Fernández-Pachón M.S. 361 

Fernández-Vázquez R. 355, 360 

Fernandez-Zamudio 

M.A. 

369, 371 

Ferragud E. 197 

Ferrándiz S. 91, 92 

Ferreira H.F. 209 

Feygenberg O. 133 

Fibla J.M. 289, 294, 330 

Fidalski J. 180 

Fidle L. 40 

Figorito B. 243 

Figueiredo J.A.G. 256 

Figueroa D. 210, 349 

Filiddani R. 244 

Filippelli S. 328 

Filippone M.P. 208, 210, 212 

Fink R.L. 214 

Fisicaro R. 244, 291, 296 

Fito P. 362 

Fito P.J. 362

Flores R. 77, 84, 235, 

237 

Flores Sanchez J.L. 199, 240 

Flors V. 293 

Folimonova S. 233, 240 

Fontana A. 237 

Fontanini D. 117 

Forner J.B. 327, 330 

Forner-Giner M.A. 158, 165, 327, 

329, 330, 331, 

332,333 

Foti S. 117 

Fourie P.H. 148, 152, 255, 

257, 259, 261 

Fraisse C.W. 270 

Francisco C.S. 43, 203, 204 

Franco J. 284 

Franco J.C. 290 

Franco S. 186 

Frasheri D. 89, 249 

Freitas-Astua J. 46, 211 

Froelicher Y. 32, 37, 49, 50, 

63, 312, 347 

Froneman I.J. 39 

Fuentes F. 242 

Fujii H. 44, 85 

Fujita K. 177 

Fujiwara Y. 48 

Fujiyama A. 62 

Fukamachi H. 97, 108 

Fullana J. 226, 297 

Furlani P.R. 205 

G 

Gabaldón T. 133, 143 

Gadea J. 76, 208,210 

Gagnevin L. 197 

Galbiatti J.A. 162, 166 

Galli-Terasawa L.V. 256, 260 

Galván J.J. 110, 111 

Gama F. 329 

Gambetta G. 97, 98 

Gandía M. 134, 139, 144 

Gao H.J. 75, 96, 139 

Gao J. 194 

Gao W. 194 

Garavello M. 319, 326 

Garbim L.F. 204 

Garcia A. 287 

García M.E. 95, 114 

Garcia M.L. 247 

García Marí F. 294 

García Martínez G. 370 

Garcia R.B. 298 

García S. 348 

García-Agustín P. 122, 264 

García-Lidón A. 145, 312 

García-Lor A. 27, 28, 31, 32, 

33, 44, 63 

Garcia-Mari F. 283, 287, 300, 

281, 289 

García-Mariscal K. 285 

García-Martínez G. 373 

García-Oller M.I. 164 

García-Sánchez F. 128, 181, 310 

Garozzo M. 244 

Garran S.M. 186, 187, 263, 

269, 298, 370 

Garrido-Jurado I. 225, 227 

Gasparoto M.C.G. 261, 266 

Gasperi G. 222 

Gatto J. 31 

Ge X.X. 317 

Genovés S. 76 

Genovese F. 357 

Gentile A. 64, 66, 95, 

138, 153 

Gerhardt N. 210 

Germanà M.A. 78, 91, 359, 

362 

Gesteira A.S. 65, 118, 125, 

315, 324 

Ghasemi S. 130 

Ghosh D.K. 216, 250 

Giacalone A. 244 

Giampetruzzi A. 237 

Giannettini J. 129 

Gil L.G. 169, 180 

Giladi B. 179, 307 

Giliomee J.H. 289 

Giménez L.I. 171, 372 

Gimeno V. 128, 181 

Girardi E.A. 65, 315, 324, 

373 

Girón J.A. 197 

Gkounti V.T. 289 

Glienke C. 82, 256, 259, 

260 

Gmitter Jr. F.G. 21, 39, 40, 42, 

61, 63, 201, 

208, 210, 325 

Goane L. 349 

Godoy W.A.C. 204 

Goes A. 257 

Goldschmidt E.E. 107 

Golmohammadi M. 209 

Gomes C. 306 

Gomes F.H.C. 184 

Gómez C. 112 

Gómez C.G. 370 

Gómez-Cadenas A. 76, 118, 119 

Gómez-Marco F. 280, 288 

Gómez-Martínez M.A. 282, 293 

Gómez-Pastor R. 122 

Gomulski L.M. 222 

Goncalves-Zuliani A. 46 

Gong G.-Z. 42 

Goñi Altuna C.T. 126 

González N. 76 

González-Candelas L. 133, 143, 145 

González-Fierro P. 150 

González-Mas M.C. 67, 68, 110 

Gordon J. 197 

Gorris M.T. 234, 242 

Gottwald T.R. 261 

Goulin E.H. 256, 259, 260 

Gowda S. 216 

Graça A. 359 

Grafton-Cardwell E. E. 275 

Graham J.H. 197, 202 

Grande S.B. 287 

Gravina A. 97, 98 

Greco G. 244 

Greenberg J. 179 

Greenblatt D.J. 40 

Griffin R.L. 22, 223 

Grosser J.W. 39, 78, 196, 

325 

Grout T.G. 275 

Gu Q.Q. 336 

Gualano S. 243 

Guan B. 51, 52, 180, 

182 

Guan L. 207 

Guardo M. 244, 247 

Guarrasi V. 359, 362 

Gübbük H. 57, 58 

Guérin F. 197 

Guerra D. 48 

Guerra M. 63 

Guerri J. 64, 236, 245, 

246, 248 

Gui-Xiang H. 28 

Gullotta S. 244 

Gulsen O. 53, 57, 318 

Gultzow D.L. 47, 263 

Guo F. 85 

Guo J. 194 

Guo Li 353 

Guo W.W. 78, 109 


Gush M.B. 157 

Guven B. 288 

Guzmán-Barney M.M. 239 

H 

Habauzit V. 344, 345 

Habu T. 97 

Hafsi A. 228 

Haigh A.M. 194 

Hamza A 170 

Han S.G. 101, 163, 335, 

336 

Han S.H. 100 

Han S.I. 69 

Handaji N. 53, 318, 326, 

328 

Handayani E. 39 

Handique P.J. 29, 89 

Hannweg K.F. 39 

Hao G.X. 193 

Happe G. 6 

Harakava R. 81, 82 

Harbi A. 228 

Hardy S. 216 

Harries E. 133, 134, 144 

Hasanzada H. 338 

Hashemi S.J 363 

Hashemi Z.S. 363 

Hasick N.J. 194 

Hattingh V. 369 

He J. 51, 52, 180, 

182 

He M. 96 

He X.-H. 49 

He Y. 338 

He Y.R. 79, 84 

Hedhly A. 95 

Hendrichs J. 221 

Hendricks K. 205 

Herbette S. 129 

Heredia F.J. 355, 360 

Hermosilla A. 242 

Hermoso de Mendoza A.242 

Hernandez D. 226 

Hernández F. 310 

Hernández L. 217 

Hernández-Crespo P. 222 

Hernanz D. 355, 360 

Herrera V. 315 

Herrero A. 61, 306 

Herrero M. 95 

Herrero-Martín G. 361 

Hershkovitz V. 133, 146 

Hervalejo A. 183, 309, 310, 

329 

Hincapie Caputo M. 255 

Hippler F.W.R. 167 

Hippolyte I. 63 

Hiraoka K. 161 

Hoffman M. 193 

Holeva M. 207 

Holford P. 194, 216, 279 

Holsman S.H. 307 

Homri N. 251 

Hong L. 80, 314, 337 

Hong Q.-B. 42 

Honsho C. 30 

Horcajada M.N. 344 

Hornero-Méndez D. 361 

Hoshino Y. 111 

Hosseini Farahi M. 338 

Hostachy B. 207 

Hu J. 255 

Hu W. 87 

Hu X. 27 

Huang C.H. 167, 336 

Huang F. 256, 263 

Huang G.H. 49 

Huang H. 200 

Huang J.Z. 56 

Huang M. 338 

Huang S. 367 

Huang X.S. 124 

Huang Xuegen 353 

Huertas-Rosales O. 222 

Hueso L. 61 

Huidrom S.D. 29, 89 

Hummer K. 21 

Hurtado M.A. 282, 293 

Hussain S. 119 

Hussain Z. 178 

Hwang R.Y. 258 

Hyun J.W. 258, 268 

I 

Ibáñez V. 61, 63, 306 

Ibarrola S. 186 

Iborra E. 42 

Iborra M. 16 

Ibriz M. 53, 252 

Ichinokiyama H.I. 113 

Ichinose K.I. 206 

Iglesias D.J. 63, 67, 68, 95, 

110 

Iida I.A. 144 


Ikoma Y. 44, 85, 97, 

100, 140 

İncesu M. 120, 127, 327 

Intrigliolo D.S. 158, 165 

Intrigliolo F. 117, 157, 160, 

172 

Inui-Kishi R.N. 209, 211 

Ioannou C.S. 222 

Ippolito A. 136, 146, 187, 

259, 268, 328 

Irey M. 196 

Iwasaki M. 108 

Izquierdo J. 297 

J 

Jacas J.A. 17, 221, 275, 

280, 282, 288, 

291, 292, 293 

Jacquemend E. 326, 328 

Jacquemoud-Collet J.C. 33 

Jaillon O. 61 

James R. Cranney Jr. 21 

Jamieson L.E. 276 

Jaquier A. 316 

Jaskani M.J. 184 

Jay-Allemand C. 347 

Jayaprakasha G.K. 343 

Jedidi E. 49 

Jensen S.P. 86 

Jeun Y.C. 267 

Jiang B. 45, 69 

Jiang D. 347 

Jiang J. 245 

Jiao B.N. 318, 347, 348, 

349 

Jie-Chun P. 28 

Jin S. 139 

Jin S.B. 69, 83 

Johnson E.G. 197, 202 

Jones M. 205 

Joshari H. 130 

Juan-Blasco M. 221 

Juárez J. 37, 49, 88, 

246, 248, 313 

Juliano Ayres A. 7 

Jumroenma K. 297 

Jung L.F. 260 

Junqueira Franco A.C.B. 162 

K 

Kabbaj T. 328 

Kacar Y. 63 

Kafa G. 53, 54, 57, 

318

Kahn T. 27, 29, 30, 

215, 310, 312 

Kaminuma E. 62 

Kamiri M. 49, 50 

Kamiya N. 148 

Kang S.B. 163, 335, 336 

Kang S.Y. 267 

Kanonich Y.K. 307 

Kaplan I. 179, 307 

Kararacoglu M. 281 

Karp D. 27, 215 

Kataoka K. 97 

Kava-Cordeiro V. 82, 256, 259, 

260 

Ke F.Z. 56, 90 

Khalid M.S. 152 

Khalid S. 152 

Khan I.A. 206, 217 

Khan M.A. 184 

Khefifi H. 101 

Khurshid T. 184, 324 

Kim J.H. 39, 69, 83 

Kim K.D. 278 

Kim S.B. 51, 102 

Kim Y.H. 101, 163, 335 

Kim Y.J. 268 

Kim Y.W. 69, 83 

King D. 343 

Kirkman W. 281 

Kishi L.T. 212 

Kita M. 28, 44, 70 

Kitajima A. 97 

Kitamura M. 177 

Ko S.W. 336 

Ko Y.J. 267 

Koh S.W. 51, 56 

Kontodimas D.C. 289 

Kornowski M.V. 261 

Koshita Y. 185 

Kotze C. 255, 258 

Koukidou M. 224 

Koutsioumari E.M. 64 

Krueger R.R. 27, 29, 31, 

178, 215 

Kudo S.A. 78 

Kulczycki Waskowicz C. 298, 348 

Kumar P.L. 238 

Kuniga T. 44 

Kunitake H. 111 

Kunta M. 194 

Kupper K.C. 150 

Kupper R.S. 333 

Kurita Y. 70 

Kuroki S. 30 

Kusaba S.K. 171 

Kutuk H. 281 

Kwon S.J. 240 

L 

La Malfa S. 47, 64, 70, 95, 

153 

La Rosa G. 95 

La Rosa R. 153, 262 

Laborda R. 287 

Labuschagne M.T. 41 

Labuschagne N. 258 

Lacey K. 305 

Lachheb N. 146 

Lacina M. 148 

Ladaniya M. 140, 354 

Lado-Lindner J. 141 

Lafuente M.T. 138, 142, 143 

Lain O. 78 

Lajara-Camilleri N. 368, 373 

Lami M.J. 212 

Langenhoven S. 259 

Lapeña L. 122, 264 

Lara-Viveros F.M. 150 

Laranjeira F.F. 217 

Larbi D. 243 

Larrechart L.L. 143 

Las Casas G. 95 

Laskowski L.L. 103 

Latado R.R. 52, 55 

Laumann R.A. 287 

Leão H.C. 324, 373 

Leduc C. 197 

Lee D.H. 336 

Lee R.F. 21, 27, 215, 

240 

Leftwich P.T. 224 

Legaz F. 158, 160, 167 

Legaz P. 345 

Lei T.G. 79 

Leite J.R.R.P. 83 

Leite Junior R.P. 335 

Leite R. 211 

Lennox C.L. 148 

Lesar K.H. 148 

Levy L. 258 

Lfadili R. 170 

Li C. 98, 99 

Li D.Z. 65, 77, 87, 

198 

Li F. 87, 198 

Li H.Y. 134, 135, 256, 

263 

Li J. 338 

Li J.H. 77 

Li N. 65, 66, 77 

Li R.H. 87 

Li S. 99 

Li X. 97 

Li Y. 87, 200 

Li Z.A. 199, 239, 241, 

245, 249 

Li Z.G. 201 

Liang G. 286 

Liang M.D. 207 

Liangzhi P. 99 

Liao C.X. 166 

Liao H. 200 

Liao H.L. 137 

Liarzi O. 264 

Licciardello C. 75, 117 

Licciardello G. 233, 244 

Lidón V. 181, 310 

Ligorio A. 146 

Lili L. 98, 99 

Lima A.A. 284 

Lima J.E.O. 177 

Lima J.E.P. 177 

Lima M.A.F. 165 

Limem Sellami E. 301 

Linde C.C. 259 

Ling P. 39 

Liquido N. J. 22, 223 

Liu J.H. 117, 124 

Liu J.J. 51, 52, 180, 

182 

Liu K.H. 245 

Liu L.P. 77 

Liu M.Y. 109 

Liu P. 139 

Liu S.Z. 139 

Liu X. 96, 338 

Liu X.F. 79, 84 

Liu Y.Z. 99 

Llauger R. 217, 271 

Llauger R.E. 95, 114 

Llop P. 209 

Llopis S. 76 

Llorens E. 122, 264 

Lo Bianco R. 162 

Lo Cicero L. 64, 86 

Lo Grasso F. 244 

Lo Piero A.R. 64, 70, 86 


Lo Presti P. 244 

Locali E.C. 204 

Loconsole G. 237 

Loeza Kuk E. 199, 240 

Loizzo M.R. 346 

Long G.Y. 66 

Lopes D. 329 

Lopes S. 193 

Lopes S.A. 203 

López A. 242 

López Arroyo J.I. 199 

López C. 84, 235 

López E. 270 

López J. 91, 92 

López M.M. 193, 209 

López N. 110, 111 

López-Climent M.F. 118 

López-García A. 61, 306 

Lotfy S. 63 

Lourenço A. 359 

Lourenço S.A. 261, 266 

Louzada E.S. 194 

Lovatt C.J. 108, 178 

Lovigu N. 33 

Lozano Leonel Junior F. 285 

Lozano-Tovar M.D. 227 

Lu S. 345, 361 

Lu X.P. 125, 167 

Luis M. 217 

Luiz F.Q.B.Q. 203 

Luo J.Q. 90 

Luo K. 66 

Luo T. 139 

Luppichini P. 296 

Luque-Williams M.J. 196 

Luro F. 27, 28, 31, 32, 

63, 101, 119, 

124, 129, 312 

M 

Ma P.Q. 55, 186 

Ma W.M. 213 

Ma X.J. 42 

Ma Y.Q 360, 361 

Ma Y.Y. 66, 337 

Ma Yaqing 353 

Ma Z.C. 347 

Mabberley D.J. 194 

Maccioni O. 354 

Machado D.L.M. 181 

Machado E.C. 110 

Machado M.A. 43, 45, 52, 61, 

65, 143, 198, 

202, 204, 209, 

211, 212, 313, 

315, 334 

Machado M.P. 90 

Machado R.S. 205, 207 

MacLeod A. 207 

Madesis P. 86 

Mafi Pashakolaei S. 230 

Magalhães de Oliveira T. 117, 125 

Magne M. 197 

Mahat K. 227 

Mahouachi J. 95 

Maia V.M. 184 

Maimone F. 244 

Makino M.H. 144 

Malacrida A.R. 222 

Malausa T. 289 

Maldonado Jr W. 227 

Malik A.U. 152 

Malik O.H. 152 

Mandel R. 178 

Manente K.K.M. 313 

Manera J. 126, 310, 317 

Manicom B.Q. 39 

Manni M. 222 

Mansilla C. 210, 349 

Mantegazza R. 33 

Manusmunkong B. 297 

Manzanilla-Ramírez 

M.A. 

285, 325 

Manzari S. 302 

Manzi M. 113 

Mara H.M. 143, 151 

Marais L.J. 269 

Marano G. 112, 244 

Marano M.R. 208, 210 

Marcet-Houben M. 133, 143 

Marcos J.F. 133, 134, 144 

Marcucci A. 160 

Marin D.R. 260, 265 

Maritz J.G.J. 39, 314 

Marnetto S. 186 

Marques A. 63 

Marques J.P.R. 266 

Marques R.N 278 

Marques V.V. 83 

Marreiros A. 185, 371 

Martelli I.B. 262 

Marti S. 229 

Martin C. 75 

Martín F. 361 


Martínez A. 110, 319 

Martínez G.C. 171 

Martínez J. 239 

Martínez M. 330, 333 

Martínez M.C. 236, 242, 248 

Martínez V. 128, 181 

Martínez-Alcántara B. 160, 167 

Martínez-Ferrer M.T. 289, 294, 330 

Martínez-Fuentes A. 97, 110, 332 

Martinez-Nicolas J. 126 

Martins C.P.S. 65 

Martins E.C. 203 

Martiz J. 38, 54 

Martorell P. 76 

Maserti E. 125 

Massenti R. 162, 163 

Massola-Junior N.S. 266 

Matallana E. 122 

Matsumoto H.M. 100, 140 

Mattos Jr. D. 159, 160, 167, 

168, 169 

Mazih A. 276 

Mazur A. 344, 345 

Mazza S.M. 171, 372 

Mazzuca S 354 

McCollum G. 42, 195 

McLeod A. 258, 259 

Meats A. 279 

Medina C.L. 205, 207 

Medina-Urrutia V.M. 109, 325 

Meier G. 359, 362 

Meléndez-Martínez A.J. 360 

Meliá Martí E. 368 

Melian Navarro A. 371 

Mendel Z. 290 

Mendes A.F.S. 65 

Mendes B.M.J. 81, 82, 88 

Mendes S. 63, 149, 306 

Meneguin L. 83 

Mennone C. 328 

Merelo P. 64, 95 

Merino C. 309, 310 

Mesejo C. 67, 68, 97, 

110, 332 

Mesquita G.L. 168 

Micheli F. 70, 125 

Micheli M. 91 

Michielin T.H.V. 52 

Mignani I. 33 

Mika R. 186, 187 

Milenkovic D. 344, 345 

Milera S. 186

Miles A.K. 263 

Miller A.M. 83 

Milonas P.G. 289 

Milone D.H. 269 

Mira J.L. 257 

Miranda M.P 278, 298 

Mirkov T.E. 63 

Misságlia J. 52 

Miyata L. 317 

Miyazaki R. 39 

Mohamadi-Shamlou M. 142 

Mohammadi-Shamloo M. 140 

Molina M.D. 165 

Molina-Nadal M.D. 332 

Moltó E. 20 

Mondal S.N. 255 

Montañola M.J. 38, 54 

Montero C.R.S. 48, 151 

Montesino L.H. 235 

Montesinos-Herrero C. 149 

Montoliu A. 119 

Monzó C. 283 

Moon Y.E 101, 163, 335, 

336 

Moore G.A. 82, 86 

Moore S.D. 281 

Mora Aguilera G. 199, 240 

Moraes A.P. 63 

Moraes J.P. 285 

Moraes M.C.B. 287 

Morales-Payán J.P. 137 

Morand C. 343, 344, 345 

Moreira J. 143, 270 

Moreno A 278 

Moreno J.M. 329 

Moreno P. 64, 77, 84, 

234, 235, 236, 

238, 245, 246, 

248 

Moretti M.R. 315 

Morgan M.R. 213 

Morgante M. 61 

Mori T. 39 

Morillon R. 31, 101, 117, 

119, 121, 124, 

125, 129 

Morte A. 122, 123 

Moschini R. 255 

Moscoso-Ramírez P.A. 149 

Motisi A. 158, 163 

Mouhib M. 53 

Moujahed R. 89 

Mourão F.A.A. 193 

Mourão Filho F. A.A. 81, 82, 88, 

183, 308, 317, 

334 

Mourão I. 185, 371 

Mousqués J. 298 

Msanda F. 147, 148 

Mu L. 63 

Muccilli V. 117 

Mulas M. 33, 111 

Müller G.W. 55, 241 

Muniz F.R. 82 

Muñoz C. 242 

Muñoz J.V. 61 

Muñoz-Fambuena N. 67, 68, 110 

Mustafa N.S. 169, 170 

N 

Nabi G. 184 

Nagasaki H. 62 

Najar A. 251 

Nakamura A.N. 171 

Nakamura Y. 62 

Nakano M. 85 

Nakazaki T. 97 

Narciso C. 201 

Nascimento A.L. 334 

Nascimento F.S.S. 333 

Nascimento L.M. 143, 270 

Nascimento S.S. 333 

Naseri M. 302 

Navarro A. 37, 85 

Navarro Acosta J.M. 157 

Navarro J.L. 344 

Navarro J.M. 122, 123, 161, 

162 

Navarro L. 3, 27, 28, 31, 

32, 33, 37, 42, 

43, 44, 49, 61, 

63, 64, 67, 77, 

84, 88, 90, 

125, 129, 235, 

236, 245, 246, 

248, 250, 264, 

313, 331 

Navarro P. 356, 358 

Navarro R. 298 

Navarro-Campos C. 281, 289 

Navarro-Llopis V. 229, 301 

Navarro-López J. 234, 238 

Negri R. M. 362 

Nesumi H. 70, 161 

Neves C.S.V.J. 335 

Neves D.M. 117, 118 

Newman T.K. 47, 263 

Nguyen C.H. 194 

Nguyen V.H.N. 206 

Nicolosi E. 33, 70 

Nie Q. 125, 167 

Nie Z.P. 90 

Nieto-Ángel D. 150 

Nieves M. 128, 310 

Nigro F. 146, 259 

Niñoles R. 67 

Nishikawa F. 108 

Nishiwaki A. 30 

Njombolwana N.S. 152 

Nocchi P.T.M. 46 

Nocchi P.T.R. 202, 212 

Noda K.N. 113 

Noga G. 128 

Nonaka K. 44 

Noriega C. 114 

Noronha Jr N.C. 298 

Novelli V.M. 46, 52, 235 

Nunes C. 149, 359 

Nunes M.A. 46 

Nunes S. 306 

Nunes W.M.C. 46, 202, 212, 

241 

Nuñez F.N. 143 

Núñez M. 95, 114 

Nurhadi N. 277, 286 

O 

Oh E.U. 51, 102 

Oh H.W. 102 

Ohta S. 28, 70 

Okuda H.O 113 

Oliva H. 114 

Olivares N. 282, 296 

Olivares-Fuster O. 90 

Oliveira A.C. 45 

Oliveira F.S. 184 

Oliveri C. 153 

Olivier V. 207 

Ollitrault F. 44, 63 

Ollitrault P. 27, 28, 31, 32, 

33, 37, 42, 43, 

44, 45, 49, 50, 

51, 61, 63, 70, 

85, 90, 119, 

121, 124, 125, 

129, 312, 347 

Olmos A. 236, 248 

Om N. 216 

Omari F.E. 124, 326 

Omura M. 44, 85 

Onelge N. 237 

Orbovic V. 196 


Orce I.G. 208 

Ordúz J. 239 

Orea Vega G. 370, 373 

Oren Y.O. 307 

Ornella L. 208 

Orozco-Santos M. 150, 285 

Ortega C. 37 

Ortega I.O. 188 

Ortega J. 158, 165 

Ortega V. 37 

Ortego F. 222 

Ortuño A. 145 

Ortúzar J.E. 367 

Otero A. 126 

Otero L. 188 

Ou Y. 166 

P 

Pacheco C.A. 262, 314, 315 

Pagliaccia P.D. 213 

Pailly O. 31, 129 

Palazzolo E. 359 

Palmeri V. 287 

Palou L. 149 

Pan J.C. 49 

Panozzo M. 359 

Paolini J. 32 

Papa R. 158 

Papachristos D.P. 222 

Papadopoulos N.T. 222 

Pardo A.P. 164 

Pardo J. 316, 358 

Parfitt S.C. 47, 263 

Parisi R. 157 

Park J.H. 51, 56 

Parra C.C. 194 

Parra J.P. 138 

Parra J.R.P. 284, 301 

Parsi F. 302 

Parsons L.R. 120 

Pasamontes A. 214 

Pascale D.P. 143 

Pasotti L. 158 

Passos O.S. 315, 324, 333, 

373 

Pastor J. 330 

Patil B.S. 343 

Patt J.M. 279 

Patti M.R. 244 

Pavan M.A. 169, 180 

Pecorino B. 372 

Pedraza J.R. 141 

Pedrosa A.M. 65 

Pedrosa-Harand A. 63 

Peirano D.J. 214 

Peiró E. 165 

Pekas A. 280, 281, 294 

Peltzer M. 91, 92 

Peña I. 217 

Peña L. 76, 77, 80, 81, 

82, 83, 84, 85, 

235, 256, 326 

Peña M. 271 

Peng A.H. 79, 84 

Peng L.Z. 98 

Peng S.A. 99 

Peng Z.C. 42 

Pensabene G. 90 

Pereira J.A. 46 

Pereira L.F.P. 83 

Pereira R. 221 

Pereira R.G. 260 

Pereira S.L.S. 65 

Pereira W.V. 266 

Perera N. 222 

Peres N.A. 255 

Pereyra M.V. 311 

Pérez A. 187 

Pérez Clemente R.M. 119 

Pérez M.C. 95, 114 

Pérez-Pérez J.G. 121, 164, 312 

Pérez-Sayas C. 293 

Perez-Tornero O. 55, 88, 123, 

312 

Peris J.E. 83 

Perrier X. 33 

Perrotta G. 292 

Pestana M. 329 

Petit F. 51 

Petters D.A.L. 256 

Peyrou M.P. 151 

Picchi S.C. 209, 211 

Píccoli A.B. 171 

Pickering G. 344 

Pickett J.A. 287 

Pietro Paolo D. 305, 328 

Pina J.A. 37, 64, 129, 

236, 245, 246, 

250, 313 

Pina T. 282, 292, 293 

Pinar H. 47 

Piñero J.P. 188 

Pino Delgado N. 208 

Pires R.C.M. 165 

Pirovani C.P. 117 


Pla M. 289, 294 

Plata M.I. 185, 326 

Plomer M. 77 

Ploper L.D. 208 

Poggi I. 96 

Poiroux-Gonord F. 96 

Polatöz S. 53, 54, 308 

Polydoro D.A. 262 

Pompeu Jr. J. 52 

Pompeu Jr. J. 43 

Pons E. 76, 81, 85 

Porat R. 353 

Porras I. 55, 88, 126, 

145, 312, 317 

Poullet T. 49, 50 

Powell C. A. 279 

Pozzan M. 211 

Pradas I. 329 

Pretorius M.C. 258 

Primo Millo J. 229, 301 

Primo-Millo E. 67, 68, 110, 

129, 331 

Prina A. 319 

Privitera S. 244 

Prudente D.A. 110 

Pruvost O. 197, 207 

Pugliese A. 346 

Punset C. 287 

Purbiati P. 286 

Pyle K.R. 100, 276 

Q 

Qi J.R. 80, 314 

Qiao Q. 245 

Qing L. 241, 247 

Qu X.Y. 336 

Quaggio J.A. 159, 160, 165, 

167, 168, 169 

Quattrocchi S. 244 

Quesada-Moraga E. 225, 227 

Quiñones A. 158, 160, 167 

Quintas C. 359 

Qureshi J.A. 205 

R 

Rabe E. 305 

Rafael G. 133, 146 

Raga A. 227, 296 

Raga V. 41 

Rahman A. 184 

Rahman H. 184 

Rahmouni R. 228, 300

Rajabi A. 130 

Rajaei H. 129 

Rambeau M. 344 

Ramón D. 76 

Ramos E. 226 

Ramos Y. C. 308, 324, 334 

Ran Y. 347 

Ranjbar S. 302 

Rapisarda P. 353, 355, 357 

Raveh E. 159 

Raza S.A. 152 

Rea E. 160, 172 

Recupero S. 305, 307, 328 

Redondo C. 197 

Reforgiato Recupero G. 61, 75, 117, 

305, 307, 328 

Reig C. 97, 110, 332 

Reis D. 185, 371 

Rempoulakis P. 224 

Rendon-Salcido L.A. 109 

Repetti M.R. 348 

Reyes C.A. 247 

Reyes J. 221 

Reza Ehsani 20 

Rezende J.A.M. 82 

Ribeiro R.V. 110, 165, 168 

Ricca G. 244 

Rikhotso V. 148 

Rinald D.A.M.F. 202 

Rinaldi S. 172 

Rinaldo D. 257 

Ripa R. 282 

Ripoll F. 332 

Ritenour M. 195 

Riu K.Z. 69, 83 

Rivadeneira M.F. 112, 309 

Rivas F. 98, 113 

Rizza G. 355 

Roberts P.D. 205 

Robles García P. 240 

Robles J.M. 164 

Robles-González M.M. 109, 285, 325 

Roccuzzo G. 157, 160, 172, 

187 

Rocha Latado R. 78 

Rodrigo M.J. 75, 76, 81, 

138, 141, 345 

Rodrigues C.M. 198, 212 

Rodrigues M.B.C. 266 

Rodrigues M.D.A. 227 

Rodríguez A. 76, 80, 81, 82, 

242 

Rodríguez Morán M. 122, 162 

Rodríguez P. 239 

Rodriguez Rubial M. 226 

Rodríguez V.A. 171 

Rodríguez-Gamir J. 331 

Rodríguez Morán M. 123 

Roeschlin R.A. 208, 210 

Rogers M.E. 278, 285 

Rojas A. 210, 349 

Roka F.M. 179, 205, 368 

Rokhsar D.S. 61 

Romañach R. 137 

Romero J. 234 

Romero P. 138, 139, 142 

Romolo F. 163 

Roose M.L. 8, 21, 42, 61, 

63, 333 

Rotolo M.C. 244 

Ruan T. 241 

Ruan X. 62 

Ruan Y. 62 

Rubio L. 237 

Rucker T.R. 240 

Rugno G.R. 204, 298, 301 

Ruíz M. 90, 129 

Ruiz Ruiz S. 234, 235, 238, 

248 

Russel P. 200 

Russo G. 305, 307, 328 

Russo M. 233, 244, 262 

Russo M.P. 244 

Ryuto K. 30 

S 

Saadi B. 147, 148 

Saavedra T. 329 

Sabater-Muñoz B. 221, 226, 228 

Sabella G. 295 

Saccini V.A.V. 207 

Sahaya S. 297 

Saitta R. 244 

Sakai K. 39, 48 

Sakaki H. 177 

Sakakibara Y. 111 

Sakamoto D. 185 

Sakata A. 30 

Sala I. 260 

Salas López H. 210, 349 

Salazar M. 149, 359 

Salazar O. 110 

Saldarelli P. 237 

Salerno M.G. 259 

Salguero A. 183, 309, 310, 

329 

Salles B.P.A. 184 

Salomão L.C.C. 181, 182, 183 

Salvador A. 356, 358 

San Biagio P. L. 359, 362 

Sanabam R.S. 89 

Sanches J.M. 143, 270 

Sanchez A. 287 

Sánchez-Baños M. 312 

Sánchez-Navarro J. 235 

Sánchez-Torres P. 133, 145 

Sanderson G. 216, 305, 324 

Santini J. 129 

Santoro F. 243 

Santos D. 182, 183 

Santos D.M.M. 207 

Santos E.M. 212 

Santos F.L 278 

Santos M.G. 315 

Sanzani S.M. 136, 146 

Saponari M. 237 

Saraceno F. 244 

Sarhan Z.H. 120 

Satar G. 281 

Satar S. 299 

Sato K.S. 97, 100 

Sato M. 39 

Sauer A.V. 202, 212 

Savaghebi Gh.R. 102 

Savi D.C. 259, 260 

Savvopoulou-Soultani 

M. 

289 

Scalschi L. 122 

Scapin M.S. 260 

Schillaci G. 244 

Schinor E.H. 52, 313, 314, 

315, 334 

Schubert T.S. 255 

Schuh R. 260 

Schumann A. 277 

Schutte G.C. 255, 257, 259, 

261 

Schwarz L.L. 151 

Schwarz S.F. 48 

Sciacca F. 117 

Scolari F. 222 

Scuderi A. 369, 372 

Sdiri S. 356, 358 

Seday S. 57 

Seday U. 47, 53, 54, 

318 

Seifi E. 140 

Seifie E. 142 

Sekula D. 293 


Sela I. 107 

Sela N. 133, 146, 264 

Sena M. 197 

Sendín L.N. 208 

Sengul M. 357 

Senkiv C.C. 256 

Sequeira R. 207 

Serfontein S. 261 

Serghini M.A. 147, 148 

Serra I.A. 354 

Serra P. 234, 248 

Server Izquierdo R.J. 368, 373 

Setamou M. 279, 293 

Severn-Ellis A.A. 39 

Sgroppo S.C. 311 

Shahid M.A. 181 

Sharifani M.M. 140, 142 

Shatters Jr. R. 195 

Shatters R. G. 279 

Shepherd A. 27 

Shi J.S. 213 

Shimada T. 44, 76, 85 

Shimizu P. 78 

Shimizu T. 19, 28, 62, 70 

Shu-Biao W. 70 

Shu-wei Z. 28 

Sicilia L. 244 

Siciliano M.F. 208 

Siciliano P. 222 

Siebert T. 29, 30, 215, 

310 

Silva A.J.M. 78 

Silva A.L.B.O. 165 

Silva E.B. 290 

Silva E.M.A. 70 

Silva F. 117 

Silva J. 207 

Silva Jr G.J. 256, 259 

Silva L.F.C. 55, 203 

Silva L.M. 78 

Silva M.F.G.F. 118 

Silva S.C. 63 

Silva S.D.R. 181 

Silva S.R. 183, 308 

Silva-Junior G.J. 260, 265 

Silva-Muller W. 112 

Silvestre Esteve E. 370 

Simón I. 128, 181, 310 

Simón-Grao S. 310 

Simonetti L.M. 52, 313 

Simsek O. 45, 47 

Simsek V.M. 299 

Sinatra V. 112, 244 

Singh S.R. 29 

Singh Z. 178 

Sippel A.D. 39, 41, 314 

Siqueira D.L. 181, 182, 183 

Siscaro G. 291, 292, 295 

Sistachs V. 114 

Slabber R. 259 

Slade G. 224 

Smith J. 207 

Smith M.W. 47, 263 

Snoussi H. 31, 32, 33 

Soares Filho W.S. 63, 65, 118, 

315, 324, 373 

Soares R.D.J. 285 

Sobolev I. 40 

Solari J.S. 143 

Soler N. 77, 84, 235 

Song J.Y. 66 

Song K.J. 102 

Song K.W. 51 

Song Z. 241, 245 

Soriano L. 317 

Sorrentino G. 244, 247 

Sosa A. 298, 348 

Soto A. 289 

Sousa M.C. 203 

Souza A.A. 198, 212 

Souza D.T. 118 

Souza F.V.D. 315 

Souza G.V. 78, 83 

Souza M.C.S. 203 

Souza T.R. 159, 160 

Spada A. 33 

Spadafora A. 244, 354 

Spooner-Hart R. 279 

Spósito M.B. 261, 265 

Srairi I. 50, 53, 318, 

326, 328 

Srijuntra S. 297 

Srikachar S. 297 

Stablum A. 186 

Stach-Machado D. 211 

Stagno F. 157 

Stansly P.A. 17, 205, 277, 

283 

Stegmayer G. 269 

Stein B. 210 

Steinberg S. 290 

Stenzel N.M.C. 335 

Stift M. 50 

Stinco C.M. 355, 360 


Stover E. 195 

Strano M.C. 357 

Stuchi E.S. 183, 308, 317, 

324, 334 

Su H.N. 199, 236 

Su X.S. 318, 347, 348, 

349 

Sugiura H. 185 

Sugiura T. 185 

Sugiyama A. 85 

Suiko M. 111 

Suma P. 290 

Sun H.J. 83 

Sun P.P. 124 

Sun X.C. 241, 247 

Sun X.H. 356 

Sun X.P. 135 

Sun Zh.G. 360 

Sun Zhigao 353 

Supriyanto A.S. 277, 286 

Sustelo V. 306 

Swart S.H. 261 

Syvertsen J.P. 126 

T 

Tadeo F.R. 61, 64, 95, 

306 

Tagari E. 179, 307 

Taha L. 133 

Tahir T. 184 

Takahara T. 177 

Takishita F. 161 

Takita M.A. 198, 209, 212 

Talha A. 123, 326 

Talha T.A. 122 

Talibi I. 147, 148, 152 

Tallón C.I. 55, 88 

Talón M. 44, 61, 63, 64, 

95, 121, 124, 

125, 306 

Tan Anqun 353 

Tanaka F.A.O. 266 

Tang K.Z. 199, 249 

Tang X.L. 55 

Tanimoto Y. 48 

Tárraga S. 68 

Tauriello A. 357 

Tavakoli A. 130 

Tavano E.C.R. 81 

Taverner P.D. 135 

Taylor N.J. 157, 168 

Tazima Z.H. 335 

Téliz-Ortiz D. 150

Tena A. 275, 280, 288 

Teresani G. 193 

Terol J. 44, 61, 63, 95, 

306 

Testolin R. 78 

Tetsumura T. 30 

Thien S. 344 

Thinlay T. 216 

Thomas C.T. 240 

Thuesen L.H. 214 

Tietel Z. 353 

Todaro A. 357 

Tolentino A. 111 

Tomás-Barberán F.A. 22, 344, 346 

Tomás-Navarro M. 344, 346 

Tomasello M. 262 

Tononi P. 117 

Torabi A.R. 363 

Tormo D. 358 

Torrents J. 330, 331 

Torres L.T. 188 

Torres P.S. 208, 210 

Torres W. 95, 114 

Torres-Leal G.J. 141, 148 

Torrisi B. 117, 160, 172 

Tosin E.S. 150 

Toyoda A. 62 

Trifiletti A. 244 

Trinchera A. 160, 172 

Tropea Garzia G. 292 

Truncali S. 244 

Tsaftaris A. 86 

Tsuruta K. 30 

Tufekli M. 281 

Tumminelli R. 112, 244 

Tuncay M. 57, 58 

Tundis R 346 

Tur C. 228 

Tur I. 32 

Turner P. 305 

Tuzcu Ö. 120, 127, 308, 

327 

Tzarfati R. 107 

U 

Ucci A.P.U. 209 

Uchida A. 111 

Uchida M. 161 

Uckoo R.M. 343 

Unlu M. 47 

Urban L. 96 

Urbaneja A. 17, 221, 275, 

280, 283, 288, 

292 

Uygun N. 299 

Uysal Kamiloğlu M. 120 

Uysal O. 53, 54, 357 

Uzun A. 47, 53, 57, 

318, 357 

V 

Vacas S. 229, 301 

Vahling-Armstrong C. 193 

Vahrmeijer J.T. 157, 168 

Valentini F. 89, 249 

Valenzuela M. 367 

Valero J.L. 165, 332 

Vallejo F. 344, 346 

Valverde-García P. 225 

Van der Walt R. 281 

Van Ekert E. 279 

van Rensburg P.J. 314 

Van Zyl J.G. 255, 257 

Vargas R. 282 

Varveri C. 236 

Vázquez D. 359, 362 

Vecchio S. 244 

Vega B. 265 

Velázquez K. 64, 236, 245, 

246, 248 

Velázquez P. 363 

Velazquez P.D. 141 

Velázquez-Monreal J.J. 285 

Venturini N. 32 

Vera L.M.V. 370, 371 

Verardi A. 346, 354 

Verdú M.J. 228 

Vernière C. 197 

Verny M.A. 344 

Verreynne J.S. 108 

Vicari M. 244 

Vicario I.M. 355, 360 

Vicent A. 42, 82, 83, 

257, 264, 266, 

267 

Vidalakis G. 213, 215, 240 

Vieira J.M. 284 

Vieira L.G.E. 78, 83 

Vieira M.L.C. 81 

Vijayakumari N. 92, 187 

Vincent P.A. 212 

Virgen-Calleros G. 109, 325 

Vital K. 197 

Vives M.C. 64, 236, 246, 

248, 250 

Vives-Peris V. 119 

Vojnov A.A. 208, 210 

Volk G.M. 27 

Voloudakis A.E. 64, 251 

Vontas J. 224 

W 

Wäckers F. 280 

Wakana A. 39, 48 

Wallace M. 305 

Wang H 360, 361 

Wang Hua 353 

Wang J. 124 

Wang J.W. 240 

Wang J.Y. 135 

Wang P. 90 

Wang X. 200, 213, 337 

Wang X.F. 199, 249 

Wang X.H. 256 

Wang Z. 96, 194 

Wangdi P. 216 

Weaver C.E. 278 

Wei Z.X. 80, 314 

Weissberg M. 40 

Wenwen Z. 99 

Weston P.H. 194 

Wi S.G. 79 

Williams T.E. 38, 307 

Williamson G. 4 

Wirtz K. 226 

Wisniewski M. 133, 146 

Wlosek Stañgret C.R. 311 

Wright G.C. 312 

Wu B. 69 

Wu C.Q. 80, 166, 314 

Wu F. 286 

Wu G. 61 

Wu H.J 360, 361 

Wu Houjiu 353 

Wu W. 186 

Wu X.M. 109 

Wulff N.A. 260 

X 

Xamani P. 287 

Xia Q. 345 

Xia Y. 194, 286 

Xia Y.L. 207 

Xiao C. 244 

Xiao S.X. 78 

Xiao Y.M. 167 

Xiaohuan M. 99 

Xie S.X. 125, 167 

Xie Y.H. 166, 337 


Xie Y.M. 87 

Xin-Hua H. 28 

Xingzheng F. 99 

Xiong Y. 241 

Xu J. 75, 80, 96, 

139, 356 

Xu J.D. 80 

Xu J.G. 56, 90 

Xu L.Z. 79, 84 

Xu M.R. 207 

Xu N. 200 

Xu Q. 62, 80, 85, 

109, 139, 317 

Xu X.B. 336 

Y 

Yada I.F.U. 335 

Yahiaoui D. 241 

Yalcin Mendi Y. 47 

Yamamoto P.T. 204, 205, 298, 

301 

Yamashita Y.K. 144 

Yan J.M. 87 

Yan J.W. 198 

Yan S.T. 337 

Yang C.Q. 99 

Yang F.Y. 236, 239, 247 

Yang L. 87, 200 

Yang R.T. 69 

Yang Y. 345 

Yang Y.L. 336 

Yaniv Y. 40 

Yano K. 70 

Yao H. 290 

Yao L.X. 79 

Yaqub M.S. 206, 217 

Yarpuzlu F. 281 

Yaseen T. 187, 268 

Ye J.L. 80 

Ye X.Q 360 

Yeşiloğlu T. 45, 47, 120, 

127, 327 

Yfran Elvira M.M. 171 

Yglesias G. 295 

Yi G.J. 45 

Yi P.H. 258, 268 

Yildirim B. 47 

Yildiz H. 357 

Yilmaz K.U. 357 

Yin Y. 345 

Yılmaz B. 120, 127, 327 

Yokomi R.K. 213, 237, 240 

Yonemori K. 97 

Yoshikawa K.Y. 171 

Yoshioka T. 28, 62, 70 

Youssef K. 146 

Yu F. 290 

Yuasa K.Y. 206 

Yun S.H. 51, 56, 69, 83, 

102, 258 

Yun Z. 80, 139 

Z 

Zacarías L. 75, 76, 81, 

138, 141, 345 

Zambrosi F.C.B. 159, 160, 169 

Zamora V. 271 

Zanardi O.Z. 298, 301 

Zandalinas S.I. 119 

Zani M.L. 165 

Zanutto C. 46 

Zanutto C.A. 202, 241 

Zappalà L. 291, 292, 295 

Zaragoza S. 316 

Zarza O. 246 

Zekri M. 177 

Zemzami M. 323 

Zeng J.W. 45, 69 


Zhang H. 224, 290 

Zhang H.Y. 75, 96 

Zhang J. 345, 361 

Zhang J.C. 80, 85 

Zhang L. 194 

Zhang L.Y. 66 

Zhang M.Q. 193 

Zhang S.W. 49 

Zhang T. 134 

Zhang W. 224 

Zhang X.Y. 318 

Zhang Y. 29 

Zhao Q.Y. 347, 348, 349 

Zhao X.L. 125, 167 

Zheng B.B. 78 

Zheng W. 224 

Zhong G.Y. 45, 66, 69, 

337 

Zhong Y. 45, 195 

Zhou C.Y. 199, 215, 236, 

239, 241, 245, 

247, 249 

Zhou L.J. 193 

Zhou W. 194 

Zhou W.J. 85 

Zhou X. 29 

Zhou Y. 239, 241, 249 

Zhu A.D. 62, 356 

Zhu S.P. 66 

Zina V. 290 

Zortea T. 270 

Zou H.S. 193 

Zou X.P. 84 

Zouahri A 170 

Zuhran Z. 286 

Zuliani-Gonçalves 

A.M.O. 

212 

Zurru R. 111

ORGANIzERS 

INSTITUTIONAL SPONSORS 

CONSELLERIA D’AGRICULTURA, 

PESCA, ALIMENTACIÓ I AIGUA 

CONSELLERIA D’EDUCACIÓ, 

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