California Pest Rating for

Pratylenchus coffeae (Zimmermann) Filipjev & Schuurmans-Stekhoven

Pest Rating: B

PEST RATING PROFILE

Initiating Event:

None. The risk of introduction and establishment of Pratylenchus coffeae is evaluated and the current rating is reviewed.

History & Status:

Background: For long, Pratylenchus coffeae has been considered a complex group of several morphologically indistinguishable species sharing a wide range of morphological variability within the group and within a single species or populations of a single species. Historically, this has resulted in a loss of the true identity of the species, and the creation of several new species based on questionable differences. Consequently, the morphological identification of P. coffeae has been based on the species complex with its high variability and identified as P. coffeae sensu lato (latin: ‘in the broad/general sense’). Numerous studies have been reported on the taxonomy of P. coffeae to clarify its identity. Molecular and phylogenetic analyses of the species complex group have now enabled the distinction of P. coffeae sensu stricto (latin: ‘in the strict/true sense’) from other distinguished representatives of the group through the development of species-specific molecular diagnostic tests. Nevertheless, most reports on biology, ecology, geographical distribution, hosts, crop loss, and regulatory actions of the species are based on the species complex group of P. coffeae. This is also true for P. coffeae detected within California.

The true status of P. coffeae (sensu stricto) in California is not known and early records, based solely on morphological analysis of the species, may be dubious. Siddiqui et al. (1973) reported the detection of P. coffeae, from 1952-1972, in residential and nursery greenhouse environments in several northern and southern coastal counties and few northern and southern valley counties, and 1 commercial site in Los Angeles County. Much of their information was from University of California nematode distribution records, nematode detection records of certain County Agricultural Commissioner offices, and the CDFA Nematology Laboratory. Then, according to CDFA Nematode Detection Records, during the 1970s, P. coffee was infrequently detected in commercial soils in Glenn, Sonoma, and Merced counties. However, there is a paucity of information on these detections and their related sites that would allow confirmation. During the 1980s, P. coffeae was detected nine times in fruit tree nursery stock root samples submitted to CDFA for analysis and certification, and once in a plant root sample from a private residence in Riverside County. The species was detected in several incoming shipments of ornamental plants imported to California nurseries under the External Quarantine Burrowing and Reniform Nematode Program. From 1990-2016, the species was detected only three times, and again in fruit tree nursery stock, while several detections were made in imported nursery ornamental plants that were intercepted in California. Except for those few nursery stock detections, it is important to note that over the past 20 years or more, P. coffeae has not been found in California soils analyzed through CDFA’s nematode detection programs and surveys of agricultural production sites, nor has its in-state presence been reported from other sources.

Pratylenchus coffeae, the banana root nematode, is a migratory endoparasite of plant roots. Depending on the host infected, P. coffeae has a life cycle of 21-28 days at 25-30°C. The nematode is able to spend its entire life cycle within root tissue and all developmental stages, adult females, and males are found within roots and rhizosphere soils of host plants. Subsequently, infested plant root stock and associated soils are potential pathways for the transportation, introduction, and spread of this species. Also, in local situations, contaminated irrigation and run-off surface water from infested fields can help spread the species to non-infested areas. The species produces lesions on feeder roots and other underground plant parts as a result of its feeding. Damage caused by the nematode results in significant yield loss and reduction for several host plants. It is likely that P. coffeae originated in the Pacific Rim/Southeast Asia region (Burke et al., 2015) and was first discovered infesting coffee roots and damaging production. It is now distributed worldwide.

Hosts: Pratylenchus coffeae attacks a wide variety of plants of over 250 plant species belonging to almost all plant families. Hosts include Citrus spp., banana, plantain, coconut, coffee, cucurbits, fig, ginger, turmeric, cardamom, potato, maize, yams, caladium, vegetables, ornamentals, and weeds.

Damage Potential: Pratylenchus coffeae infects roots, tubers, corms, and rhizomes of host plants causing damage to the cortical tissue which results in development of lesions, weakened root systems, rot, stunting, death of plant, reduction in crop production and yield loss. Root lesions become avenues for secondary infections of fungi and bacteria. Crop losses up to 80% in Musa sp. (banana) are reported from South Africa (Sarah, 1989) and 60% production loss of plantains in Ghana (Burke, et al., 2015). In the United States, growth of citrus rootstock was reduced by 49-80% due to P. coffeae and fruit yields on rough lemon and sour orange rootstocks were reported 143% and 231% higher respectively, than trees infected with P. coffeae in the first bearing year, and 220% and 271% more in the second year (O’Bannon & Tomerlin, 1973).

Worldwide Distribution: Banana root nematode was originally discovered in Java, Indonesia. It is found worldwide, although distributed primarily in tropical and subtropical regions. Most reports record the occurrence of the species complex Pratylenchus coffeae sensu lato from Asia: Afghanistan, Bangladesh, Bhutan, Brunei Darussalam, China, India, Indonesia, Iran, Japan, Korea, Malaysia, Oman, Pakistan, Philippines, Sri Lanka, Papua New Guinea, Taiwan, Thailand, Turkey, Vietnam; Africa: Cameroon, Côte d’Ivoire, Ghana, Kenya, Madagascar, Malawi, Mauritius, Mozambique, Nigeria, Seychelles, South Africa, Swaziland, Tanzania, Uganda, Zambia, Zimbabwe; North America: Canada, Mexico, USA; Central America and Caribbean: Belize, Costa Rica, Cuba, Dominica, Dominican Republic, El Salvador, Grenada, Guadeloupe, Guatemala, Honduras, Jamaica, Martinique, Nicaragua, Panama, Puerto Rico, Trinidad and Tobago; Europe: Austria, Bulgaria, Italy, Slovenia, Spain; South America: Brazil, Chile, Colombia, Ecuador, French Guiana, Suriname, Venezuela; Oceania: Australia, Cook Island, Fiji, Kiribati, Niue, Palau, Papua New Guinea(CABI, 2014; Castillo & Vovlas, 2007; EPPO, 2014).

In the USA, Pratylenchus coffeae has been reported in Arkansas, California, Florida, Hawaii, North Carolina, and South Carolina (CABI, 2014; Castillo & Vovlas, 2007; EPPO, 2014).

Official Control: Pratylenchus coffeae is a phytosanitary risk in all tropical and subtropical countries (CABI, 2016). Currently, P. coffeae is a C-rated pathogen in California. The nematode species is on the ‘Harmful Organism Lists” for Argentina, Canada, Chile, French Polynesia, Indonesia, Madagascar, Morocco, New Caledonia, Timor-Leste, and Uruguay (USDA-PCIT, 2016).

California Distribution: The true presence and distribution of Pratylenchus coffeae in California is not known as identification was based primarily on the species complex group (see “Background”). However, from 1996 to May, 2016, P. coffeae was detected three times in CDFA’s Nursery Stock Nematode Certification Program: once in Los Angeles County (2002), once in Riverside County (1997), and once in Santa Barbara County (1998).

California Interceptions: Pratylenchus coffeae has been detected in several incoming shipments of ornamental plants imported to California nurseries under the External Quarantine Burrowing and Reniform Nematode Program.

This risk banana root nematode, Pratylenchus coffeae would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

Risk is Medium (2): Pratylenchus coffeae is likely to establish wherever its infected host is able to establish within California. However, even with this capability, and since the early 1970s, P. coffeae has not been reported from California’s agricultural crop production sites, nor is it known to be established widely within California. Therefore, a ‘medium’ risk is assessed for this category.

2) Known Pest Host Range: Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

Risk is High (3): Pratylenchus coffeae attacks a wide variety of plants of over 250 plant species belonging to almost all plant families. Citrus, fruit trees, and ornamentals are some of the main susceptible hosts of concern for California.

3) Pest Dispersal Potential: Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

Risk is High (3): Pratylenchus coffeae is spread over long distances primarily through infested plant root stock and associated soils. Short-distance spread is through run-off irrigation water, infested and planting root stock, and movement of contaminated soil.

4) Economic Impact: Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

Risk is Medium (2): Pratylenchus coffeae infects roots, tubers, corms, and rhizomes of host plants causing reduction in crop yield and possible loss of markets.

5) Environmental Impact: Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

Risk is Medium (2): Pratylenchus coffeae could significantly impact cultural practices, home/urban gardening or ornamental plantings.

**Consequences of Introduction to California for Pratylenchus coffeae:**

Add up the total score and include it here. (Score)

-Low = 5-8 points

–Medium = 9-12 points

-High = 13-15 points

Total points obtained on evaluation of consequences of introduction to California = 12 (Medium).

6) Post Entry Distribution and Survey Information: Evaluate the known distribution in California. Only official records identified by a taxonomic expert and supported by voucher specimens deposited in natural history collections should be considered. Pest incursions that have been eradicated, are under eradication, or have been delimited with no further detections should not be included. (Score)

-Not established (0) Pest never detected in California, or known only from incursions.

-Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

-High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Evaluation is Medium (-2): The true presence and distribution of Pratylenchus coffeae in California is not known, however, from 1996 to May, 2016, P. coffeae was detected three times in CDFA’s Nursery Stock Nematode Certification Program: once in Los Angeles County (2002), once in Riverside County (1997), and once in Santa Barbara County (1998).

Final Score:

7) The final score is the consequences of introduction score minus the post entry distribution and survey information score: (Score)

Final Score: Score of Consequences of Introduction – Score of Post Entry Distribution and Survey Information = 10 (Medium).

Uncertainty:

The status of Pratylenchus coffeae in California’s natural environment is not known. Also, not known is the true identity of members of the species complex in California.

Conclusion and Rating Justification:

Based on the evidence provided above the proposed rating for banana root nematode, Pratylenchus coffeae is B.

References:

Burke, M., E. H. Scholl, D. Mck. Bird, J. E. Schaff, S. Coleman, R. Crowell, S. Diener, O. Gordon, S. Graham, X. Wang, E. Windham, G. M. Wright, and C. H. Opperman. 2015. The plant parasite Pratylenchus coffeae carries a minimal nematode genome. Nematology 17:621-637. http://dx.doi.org/10.1163/15685411-00002901.

CABI. 2014. Pratylenchus coffeae (banana root nematode) basic datasheet. http://www.cabi.org/cpc/datasheet/43903.

Castillo, P. and N. Vovlas. 2007. Pratylenchus (Nematoda: Pratylenchidae): diagnosis, biology, pathogenicity and management. Hunt, D. J., and R. N. Perry (Series Eds).Nematology monographs and perspectives. Brill Leiden-Boston. 529 p.

O‘Bannon, J. H., and A. T. Tomerlin. 1973. Citrus tree decline caused by Pratylenchus coffeae. Journal of Nematology, 5(4):311-316.

Sarah, J. L. 1989. Banana nematodes and their control in Africa. Nematropica, 19:199-215.

Siddiqui, I. A., S. A. Sher, and A. M. French. 1973. Distribution of plant parasitic nematodes in California. State of California Department of Food and Agriculture Division of Plant Industry. 324 p.

USDA-PCIT. 2016. United States Department of Agriculture, Phytosanitary Certificate Issuance & Tracking System (PCIT). https://pcit.aphis.usda.gov/PExD/faces/ViewPExD.jsp .

Responsible Party:

John J. Chitambar, Primary Plant Pathologist/Nematologist, California Department of Food and Agriculture, 3294 Meadowview Road, Sacramento, CA 95832. Phone: (916) 262-1110, plant.health[@]cdfa.ca.gov.

Comment Period: CLOSED

The 45-day comment period opened on Jun 29, 2016 and closed on Aug 13, 2016.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: B

Posted by ls

Hemiptera, Insects, Mites & Earthworms

Aonidiella orientalis (Newstead): Oriental Scale

June 24, 2016 Jason Leathers

California Pest Rating for

Aonidiella orientalis (Newstead): Oriental Scale

Hemiptera: Diaspididae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

Aonidiella orientalis is frequently intercepted by CDFA. A pest rating proposal is required to support its pest rating.

History & Status:

Background: Aonidiella orientalis is a highly polyphagous armored scale insect. It feeds on the leaves of a wide variety of plants and is regarded as an economic pest of citrus, tea, dates, palms, papaya, mango, and ornamentals¹. Known hosts include: Acanthaceae: Adhatoda vasica¹, Barleria cristata¹, Thunbergia grandiflora¹; Amaranthaceae: Bassia latifolia¹; Anacardiaceae: Mangifera indica¹, Pistacia integerrima¹, Spondias cytherea¹; Annonaceae: Annona squamosa¹, Annona glabra¹, Annona¹, Polyalthia korihthi¹, Polyathia¹, Rollinia emarginata¹; Apocynaceae: Alstonia scholaris¹, Alstonia¹, Calotropis¹, Calotropis procera¹, Carissa carandas¹, Carissa¹, Nerium¹, Nerium oleander¹, Plumeria¹, Tabernaemontana coronaria¹, Tabernaemontana¹; Araliaceae: Hedera¹; Arecaceae: Cocos nucifera¹, Cocos¹, Inodes neglecta¹, Loroma amethystiora¹, Phoenix¹, Phoenix dactylifera¹, Phoenix¹, Roystonea regia¹; Aristolochiaceae: Aristolochia¹; Asparagaceae: Agave variegata¹, Agave sisalana¹, Agave americana¹, Agave¹; Bignoniaceae: Bignonia vinusta¹, Bignonia radicans¹, Kigelia pinnata¹, Oroxylum indicum¹, Tecoma australis¹, Tecoma undulata¹, Tecoma stans¹; Boraginaceae: Cordia rothii¹, Cordia myxa¹, Cordia¹, Cordia obliqua¹, Ehretia serrata¹; Burseraceae: Boswellia serrata¹, Bursera serrata¹; Buxaceae: Buxus sempervirens¹; Cactaceae: Cactus¹, Opuntia¹; Cannaceae: Canna indica¹; Capparaceae: Crataeva religiosa¹; Caprifoliaceae: Lonicera chinensis¹, Sambucus javanica¹; Caricaceae: Carica papaya¹, Carica papaya¹; Celastraceae: Catha edulis¹, Celastrus paniculata¹; Combretaceae: Quisqualis indica¹, Terminalia belerica¹, Terminalia arjuna¹; Convolvulaceae: Calonyction roxburghii¹, Ipomoea¹, Porana paniculata¹; Cunoniaceae: Weinmannia¹; Cycadaceae: Cycas revoluta¹, Cycas¹; Ebenaceae: Diospyros¹, Diospyros montana¹, Diospyros embryopteris¹; Elaeagnaceae: Elaeagnus pungens¹; Euphorbiaceae: Acalypha¹, Bischofia javanica¹, Croton tiglium¹, Mallotus philippinensis¹, Phyllanthus myrtifolius¹, Poinsettia¹, Putranjiva roxburghii¹, Ricinus¹, Ricinus communis¹, Sapium sebiferum¹; Fabaceae: Acacia cyanophila¹, Albizia lebbek¹, Albizia¹, Atylosia¹, Atylosia candollii¹, Bauhinia variegata¹, Bauhinia¹, Bauhinia purpurea¹, Bauhinia alba¹, Bauhinia vahlii¹, Bauhinia racemosa¹, Butea frondosa¹, Caesalpinia bonducella¹, Cassia¹, Cassia auriculata¹, Cassia fistula¹, Ceratonia siliqua¹, Dalbergia¹, Dalbergia lanceolaria¹, Dalbergia sissoo¹, Erythrina crista¹, Inga dulcis¹, Poinciana regia¹, Pongamia glabra¹, Saraca indica¹, Tamarindus¹, Tamarindus indica¹, Tephrosia¹; Heliconiaceae: Heliconia¹; Liliaceae: Aloe vera¹, Asparagus sprengeri¹, Asparagus¹; Lythraceae: Lagerstroemia indica¹, Lawsonia inermis¹, Punica granatum¹; Magnoliaceae: Magnolia grandiflora¹; Malpighiaceae: Hiptage madablota¹; Malvaceae: Adansonia¹, Bombax malabaricum¹, Eriodendron anfractuosum¹, Grewia asiatica¹, Hibiscus¹, Pterospermum acerifolium¹, Sterculia¹, Sterculia alata¹; Melastomataceae: Osbeckia¹, Wrightia coccinea¹, Meliaceae: Azedarach indica¹, Cedrela toona¹, Melia volkensii¹, Melia¹, Melia indica¹, Melia composita¹, Melia azadirachta¹, Swietenia mahagoni¹; Menispermaceae: Cocculus laurifolius¹; Moraceae: Broussonetia papyrifera¹, Ficus benghalensis¹, Ficus salicifolia¹, Ficus glomerata¹, Ficus infectoria¹, Ficus nitida¹, Ficus orbicularis¹, Ficus palmata¹, Ficus religiosa¹, Ficus carica¹, Ficus retusa¹, Ficus roxburghii¹, Ficus¹, Ficus elastica¹, Maclura aurantiaca¹, Morus¹, Morus alba¹, Morus laevigata¹; Moringaceae: Moringa pterygosperma¹; Musaceae: Musa¹, Musa sapientum¹; Myrtaceae: Callistemon rigidus¹, Eucalyptus¹, Eugenia jambolana¹, Eugenia¹, Myrrhinium rubriflorum¹, Myrtus communis¹, Psidium guajava¹; Nyctaginaceae: Bougainvillea¹, Mirabilis jalapa¹, Nyctaginia¹; Ochnaceae: Ochna squarrosa¹; Oleaceae: Jasminum¹, Olea europaea¹; Orchidaceae:¹; Oxalidaceae: Averrhoa carambola¹; Poaceae: Panicum¹; Podocarpaceae: Podocarpus neriifolius¹, Podocarpus lamberti¹; Polygonaceae: Antigonon leptopus¹; Proteaceae: Grevillea robusta¹; Ranunculaceae: Clematis paniculatus¹; Rhamnaceae: Rhamnus persicus¹, Ziziphus oenoplia¹, Ziziphus¹, Ziziphus jujuba¹; Rhizophoraceae: Bruguiera sexangulata¹, Rhizophora mucronata¹; Rosaceae: Eriobotrya japonica¹, Prunus armeniaca¹, Pyrus sinensis¹, Rosa¹; Rubiaceae: Stephegyne parviflora¹; Rutaceae: Aegle marmelos¹, Aegle¹, Casimiroa¹, Chloroxylon swietenia¹, Citrus trifoliata¹, Citrus limon¹, Citrus aurantium¹, Citrus¹, Feronia elephantum¹, Limonia¹, Murraya exotica¹, Murraya exotica¹; Salicaceae: Populus alba¹, Populus euphratica¹, Salix tetrasperma¹; Santalaceae: Santalum album¹; Sapindaceae: Acer pictum¹, Acer oblongum¹, Dodonaea viscosa¹, Litchi chinensis¹, Nephelium litchi¹, Sapindus detergens¹; Sapotaceae: Mimusops elengi¹, Mimusops kauki¹; Simaroubaceae: Ailanthus aladulosa¹; Solanaceae: Solanum melongena¹, Solanum arundo¹; Theaceae: Camellia¹, Thea¹; Ulmaceae: Celtis¹, Celtis australis¹, Ulmus integrifolia¹, Ulmus¹; Verbenaceae: Callicarpa macrophyla¹, Citharexylum subserratum¹, Clerodendrum phlomoides¹, Duranta ellisi¹, Duranta plumieri¹, Gmelina arborea¹, Nyctanthes arbor-tristis¹, Vitex negundo¹; Vitaceae: Vitis vinifera¹, Zamiaceae: Zamia¹; Zingiberaceae: Alpinia nutans¹. Aonidiella orientalis may be transported long distances when infested plants or fresh plant parts are moved.

Worldwide Distribution: Aonidiella orientalis is presumably native to Asia and has spread through much of the Neotropical, Afrotropical, Palearctic, and Oceanic regions. In North America it is only known to be established in Florida¹.

Official Control: Aonidiella orientalis is listed as a harmful organism by Chile, Colombia, Costa Rica, Honduras, Japan, and the Republic of Korea².

California Distribution: Aonidiella orientalis has never been found in California.

California Interceptions: From 1987 through 2015 Aonidiella orientalis was intercepted 225 times by CDFA’s high risk programs, dog teams, and border stations. Many of these interceptions have been on coconut, papaya, and mango from Florida, Brazil, and Mexico.

The risk Aonidiella orientalis (Oriental scale) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Due to its highly polyphagous nature and known distribution across a range of climates Aonidiella orientalis can be expected to establish a widespread distribution in California. It receives a High (3) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Aonidiella orientalis is known to feed on hundreds of species in at least 67 plant families. It receives a High (3) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Dispersal Potential: Scale insects are capable of rapid reproduction and can be transported long distances when infested plants or fresh plant parts are moved. They may also disperse locally by crawling, wind, or by hitchhiking on clothing, equipment, or animals. Aonidiella orientalis receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: Aonidiella orientalis is considered an economic pest of several crops that are grown in California and may be expected to lower crop yields and increase crop production costs. Oriental scale is listed as a harmful organism by several of California’s trading partners. If the scale were to enter the state it may disrupt markets for fresh fruit and nursery stock. Aonidiella orientalis receives a High (3) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Aonidiella orientalis is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. It may feed on endangered and threatened species such as small-leaved rose (Rosa minutifolia). Oriental scale is not expected to disrupt critical habitats. It may trigger additional official or private treatment programs in orchards, the nursery industry, and by residents who find infested plants unacceptable. Aonidiella orientalis may also significantly impact cultural practices, home/urban gardening, and ornamental plantings. It receives a High (3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

**Consequences of Introduction to California for Aonidiella orientalis (Oriental Scale): High (15)**

Add up the total score and include it here.

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Aonidiella orientalis has never been found in California and receives a Not established (0) in this category.

Evaluate the known distribution in California. Only official records identified by a taxonomic expert and supported by voucher specimens deposited in natural history collections should be considered. Pest incursions that have been eradicated, are under eradication, or have been delimited with no further detections should not be included.

–Not established (0) Pest never detected in California, or known only from incursions.

–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score

The final score is the consequences of introduction score minus the post entry distribution and survey information score: High (15)

Uncertainty:

There have not been any recent surveys for oriental scale in California. It is possible that it could be established in some localities.

Conclusion and Rating Justification:

Aonidiella orientalis has never been found in California and is likely to have significant economic and environmental impacts if it were to enter the state. An “A” rating is justified.

References:

¹ Miller, Dug, Yair Ben-Dov, Gary Gibson, and Nate Hardy. ScaleNet.

http://scalenet.info/catalogue/Aonidiella%20orientalis/

http://scalenet.info/validname/Aonidiella/orientalis/

² USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: A

Posted by ls

Hemiptera, Insects, Mites & Earthworms

Clavaspis herculeana (Common Name): Herculeana Scale

June 24, 2016 Jason Leathers

California Pest Rating for

Clavaspis herculeana (Common Name): Herculeana Scale

Hemiptera: Diaspididae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

Clavaspis herculeana is commonly intercepted by CDFA. A pest rating proposal is required to support its pest rating.

History & Status:

Background: Clavaspis herculeana is a polyphagous armored scale insect. It burrows beneath the surface of twigs and branches and feeds by sucking juices from plants while concealed beneath the epidermis of its host-plants^1,2. Known hosts include: Anacardiaceae: mango (Mangifera indica^1,2), Mangifera cambodiana^1,2, Mangifera spp.^1,2; Florida poisontree (Metopium toxiferum^1,2), ambarella (Spondias dulcis^1,2), jocote (Spondias purpurea^1,2), Spondias cytherea^1,2; Annonaceae: sugar apple (Annona squamosa^1,2), soursop (Annona muricata^1,2), Annona spp.^1,2; Apocynaceae: Plumeria rubra, Plumeria sp. (numerous CDFA interceptions); Bignoniaceae: pink trumpet tree (Tabebuia heterophylla^1,2); Bixaceae: buttercup tree (Cochlospermum vitifolium^1,2); Caricaceae: papaya (Carica papaya^1,2); Euphorbiaceae: tung-oil tree (Aleurites fordii^1,2), Aleurites spp.^1,2; Fabaceae: sweet acacia (Acacia farnesiana^1,2), Acacia flexicaulis^1,2, golden shower tree (Cassia fistula^1,2), royal Poinciana (Delonix regia^1,2), coast coral tree (Erythrina caffra^1,2), coral tree (Erythrina indica^1,2), Erythrina spp.^1,2, Lonchocarpus spp.^1,2, Lonchocarpus latifolius^1,2, sensitive plant (Mimosa pudica^1,2), monkey-pod (Pithecellobium saman^1,2); Lauraceae: Cinnamomum sp.^1,2, true cinnamon tree (Cinnamomum zeylanicum^1,2); Magnoliaceae: southern magnolia (Magnolia grandiflora^1,2); Malvaceae: Eriodendron anfractuosum^1,2, Eriodendron spp.^1,2, Gossypium spp.^1,2; Meliaceae: Cedrela toona^1,2; Moraceae: common fig (Ficus carica^1,2), Ficus spp.^1,2, Roxburgh fig (Ficus roxburgii^1,2), sacred fig (Ficus religiosa^1,2), Ficus capensis^1,2, old fustic (Maclura tinctoria^1,2), white mulberry (Morus alba^1,2); Myristicaceae: Myristica hypargyraea^1,2; Myrtaceae: Eugenia spp.^1,2; Polygonaceae: Muehlenbeckia sagittiformis^1,2; Proteaceae: southern silky oak (Grevillea robusta^1,2); Rhizophoraceae: Rhizophora spp.^1,2; Rosaceae: loquat (Eriobotrya japonica^1,2), pear (Pyrus spp.^1,2), rose (Rosa spp.^1,2); Rubiaceae: buttonbush (Cephalanthus occidentalis^1,2); Rutaceae: Citrus spp.^1,2; Salicaceae: poplar (Populus spp.^1,2), Xylosma venosum^1,2; Santalaceae: Phoradendron randiae^1,2; Styracaceae: Halesia spp.^1,2; Verbenaceae: Avicennia nitida^1,2. Clavaspis herculeana may be transported long distances when infested plants or fresh plant parts are moved.

Worldwide Distribution: Clavaspis herculeana is widespread in many parts of the Australasian, Afrotropical, Oriental, Palearctic, and Neotropical regions^1,2. It is present in Mexico, Texas, Florida, and Hawaii^1,2.

Official Control: Clavaspis herculeana is listed as a harmful organism by Japan and the Republic of Korea³.

California Distribution: Clavaspis herculeana has never been found in the environment of California.

California Interceptions: From 1988 through 2015 Clavaspis herculeana was intercepted 45 times by California’s high risk programs, dog teams, and border stations. Most of these interceptions have occurred on plants or fresh plant parts from Hawaii, primarily Plumeria rubra or Plumeria sp.

The risk Clavaspis herculeana (Herculeana scale) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Clavaspis herculeana is polyphagous on a wide variety of plants that are widely grown in California and is likely to establish wherever they are grown. It receives a High (3) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Clavaspis herculeana is known to feed on plants in at least 25 families. It receives a High (3) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Dispersal Potential: Scale insects are capable of rapid reproduction and can be transported long distances when infested plants or fresh plant parts are moved. They may also disperse locally by crawling, wind, or by hitchhiking on clothing, equipment, or animals. Its cryptic habits mean that herculeana scale may easily be dispersed by trade in infested plants without being detected. Clavaspis herculeana receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: Clavaspis herculeana has not been documented as lowering any crop yields. It may lower the value of nursery stock by disfiguring plants with its presence and increase fresh fruit production costs. Herculeana scale is listed as a harmful organism by several of California’s trading partners and its entry to the state may disrupt fresh fruit and nursery stock export markets. This scale is not expected to change cultural practices, vector other organisms, injure animals, or disrupt water supplies. Clavaspis herculeana receives a Medium (2) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Clavaspis herculeana is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. It is likely to feed on endangered or threatened species including small-leaved rose (Rosa minutifolia). Herculeana scale is not expected to disrupt critical habitats. It may trigger additional treatment programs in fresh fruit and nursery industries. It is not expected to significantly impact cultural practices, home/urban gardening, or ornamental plantings. Clavaspis herculeana receives a High (3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

**Consequences of Introduction to California for Clavaspis herculeana (Herculeana scale): High (14)**

Add up the total score and include it here.

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Clavaspis herculeana has never been found in California and receives a Not established (0) in this category.

–Not established (0) Pest never detected in California, or known only from incursions.

–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score

The final score is the consequences of introduction score minus the post entry distribution and survey information score: High (14)

Uncertainty:

Clavaspis herculeana is reported to be associated with the fungus Septobasidium saccardinum^1,2. This relationship is not clear.

Conclusion and Rating Justification:

Clavaspis herculeana has never been found in California and is expected to have significant economic impacts to California’s fresh fruit and nursery industries if it enters the state. It is also expected to have significant environmental impacts. An “A” rating is justified.

References:

¹ Miller, Dug, Yair Ben-Dov, Gary Gibson, and Nate Hardy. ScaleNet. http://scalenet.info/validname/Clavaspis/herculeana/

² SEL Catalog. http://www.sel.barc.usda.gov/catalogs/diaspidi/Clavaspisherculeana.htm

³ USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: A

Posted by ls

Hemiptera, Insects, Mites & Earthworms

Halticus bractatus (Say): Garden Fleahopper

June 24, 2016 Jason Leathers

California Pest Rating for

Halticus bractatus (Say): Garden Fleahopper

Hemiptera: Miridae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

Halticus bractatus was recently intercepted by one of CDFA’s border stations on outdoor plants from Florida. Although this insect is included on some old pest lists with a “C” rating, all PDRs for the species to date have been assigned a temporary rating of “Q”. A pest rating proposal is required to assign a permanent pest rating.

History & Status:

Background: Halticus bractatus is a polyphagous pest that feeds on a variety of crops including citrus¹. It prefers to feed on hosts in the family Fabaceae including alfalfa, beans, peas, and clovers but will readily feed on many other plants including barley, beets, cabbage, celery, corn, cotton, cucumber, eggplant, lettuce, oats, pepper, potato, pumpkin, squash, sweet potato, tomato, tobacco, and wheat^1,2. It also feeds on many weeds and occasionally other insects². Adult females insert eggs into the stems of vegetation². Nymphs and adults suck juices from the stems and surfaces of leaves². Feeding causes whitish or yellow speckling on the foliage, stunts plant growth, and may cause the death of seedlings². Nymphs and adults deposit black fecal material that reduces the marketability of vegetables². Halticus bractatus may be transported long distances when infested plants or fresh plant parts are moved.

Worldwide Distribution: Halticus bractatus is widespread in the eastern United States and Canada as far west as the Rocky Mountains^1,2. It is found throughout Central and South America^1,2. It is also present in Hawaii.

Official Control: Halticus bractatus is listed as a harmful organism by Guatemala, Mexico, Japan, and the Republic of Korea³.

California Distribution: Halticus bractatus has never been found in the environment of California.

California Interceptions: Halticus bractatus has been intercepted twice by CDFA on outdoor plants from Florida and Ocimum sp. from Hawaii. Unidentified species of Halticus have also been intercepted twice on plant cuttings and herbs from Hawaii.

The risk Halticus bractatus (garden fleahopper) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Halticus bractatus is widespread east of the Rockies from Canada to Argentina. It is likely capable of establishing a widespread distribution in California and receives a High (3) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Halticus bractatus is highly polyphagous and receives a High (3) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Dispersal Potential: Halticus bractatus has a high reproductive rate. Under favorable conditions it can complete a generation in 30 days and each female produces 80-100 eggs. Despite its polyphagous nature and widespread distribution in the eastern United States it has only been intercepted by CDFA a few times. This indicates it may not move often in commerce. Halticus bractatus receives a Medium (2) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: Halticus bractatus is not typically a pest of commercial agriculture because it is controlled by insecticides used against more damaging pests². If it were to establish in California it is not expected to lower crop yields. It may reduce the value of nursery stock and fresh vegetables by disfiguring these commodities. It is also listed as a harmful organism by several of California’s trading partners and therefore has the potential to disrupt markets. It is not expected to change cultural practices, vector other organisms, injure animals, or interfere with water supplies. Halticus bractatus receives a Medium (2) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: If Halticus bractatus were to establish in California it is not likely to lower biodiversity, disrupt natural communities, or change ecosystem processes. It may feed on threatened and endangered species such as showy indian clover (Trifolium amoenum), Pacific grove clover (Trifolium polyodon), and Monterey clover (Trifolium trichocalyx). It is not likely to disrupt critical habitats. It is not expected to trigger new treatment programs in commercial agriculture. However, in Florida it is a common early season pest in home gardens. Home/urban gardening may be significantly impacted by this pest and it may trigger new treatment programs in this environment. Halticus bractatus receives a High (3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

**Consequences of Introduction to California for Halticus bractatus (Garden Leafhopper): High (13)**

Add up the total score and include it here.

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Halticus bractatus has never been found in California and receives a Not established (0) in this category.

–Not established (0) Pest never detected in California, or known only from incursions.

–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score

The final score is the consequences of introduction score minus the post entry distribution and survey information score: High (13)

Uncertainty:

In the eastern United States Halticus bractatus is attacked by many other organisms including egg and nymph parasitoids, predatory mites, and nematodes². It is possible that the bug could be more damaging in California in the absence of these natural enemies.

Conclusion and Rating Justification:

Halticus bractatus has not been found in California and it is likely to have significant impacts if it were to establish in the state. An “A”-rating is justified.

References:

¹ Henry, Thomas J. 1983. The Garden Fleahopper Genus Halticus (Hemiptera: Miridae): Resurrection of an Old Name and Key to Species of the Western Hemisphere. Proc. Entomol. Soc. Wash. 85(3):607-611. https://research.amnh.org/pbi/library/0332.pdf

² Capinera, John L. 2014. Common name: garden fleahopper. University of Florida Featured Creatures. http://entnemdept.ufl.edu/creatures/veg/leaf/fleahopper.htm

³USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: A

Posted by ls

Hemiptera, Insects, Mites & Earthworms

Ceroplastes stellifer (Westwood): Stellate Scale

June 24, 2016 Jason Leathers

California Pest Rating for

Ceroplastes stellifer (Westwood): Stellate Scale

(synonym Vinsonia stellifera)

Hemiptera: Coccidae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

Ceroplastes stellifer is regularly intercepted by CDFA and is presently assigned a temporary rating of “Q”. A pest rating proposal is required to determine a permanent pest rating.

History & Status:

Background: Ceroplastes stellifer is a polyphagous soft scale insect that feeds on a variety of plants including many crops and ornamentals. Some of the known hosts include: Anacardiaceae: mango (Mangifera indica¹), Mangifera sp.¹; Apocynaceae: blackboard tree (Alstonia scholaris¹), Ervatamia orientalis¹, frangipani (Plumeria acutifolia¹); Araliaceae: Schefflera sp.¹; Arecaceae: coconut (Cocos nucifera¹), Cocos sp.¹; Aspleniaceae: Asplenium sp.¹; Clusiaceae: Clusia sp.¹, purple mangosteen (Garcinia mangostana¹), bitter garcinia (Garcinia spicata¹), kokum (Garcinia indica¹), Garcinia sp.¹; Ebenaceae: velvet apple (Diospyros discolor¹); Euphorbiaceae: bishop wood (Bischofia javanica¹); Lauraceae: camphor tree (Cinnamomum camphora¹), avocado (Persea americana¹); Liliaceae: asparagus fern (Asparagus sprengeri¹); Moraceae: Artocarpus integra¹, banyan (Ficus benghalensis¹), Ficus antimesma¹; Musaceae: Musa sp.¹; Myrtaceae: Eucalyptus sp.¹, jambos (Eugenia jambos¹), jambul (Eugenia jambolana¹), water apple (Eugenia aquea¹), Eugenia sp.¹, java plum (Syzygium cuminii¹); Orchidaceae: blood red broughtonia (Broughtonia sanguinea¹), Cattleya sp.¹, Cypripedium niveum¹, fringed star orchid (Epidendrum ciliare¹), Epidendrum sp.¹, Stanhopea sp.¹; Phyllanthaceae: Chinese-laurel (Antidesma bunius¹); Polypodiaceae: Adiantum sp.¹; Primulaceae: coralberry (Ardisia polycephala¹); Rutaceae: grapefruit (Citrus grandis¹), bitter orange (Citrus aurantium¹), Citrus sp.¹, orangeberry (Glycosmis pentaphylla¹), Jambolana sp.¹; Sapotaceae: sapodilla (Achras sapota¹), Lucuma caimito¹, Palaquium sp.¹; Strelitziaceae: traveller’s palm (Ravenala madagascariensis¹); Zingiberaceae: red ginger (Alpinia purpurata¹). The scale has also been found feeding on additional hosts^3,4. Ceroplastes stellifer may be transported long distances when infested plants or fresh plant parts are moved.

Worldwide Distribution: The native range of Ceroplastes stellifer is uncertain but early records are from the Caribbean¹. It is now widespread in parts of Australia, the Pacific, Africa, Asia, and South America¹. In the United States it is found in Florida, Alabama, and Georgia¹. Interceptions indicate that it may also be present in Hawaii.

Official Control: Ceroplastes stellifer is listed as a harmful organism by China, Japan, the Republic of Korea, and Mexico (see Vinsonia stellifera)².

California Distribution: Ceroplastes stellifer has never been found in the environment of California.

California Interceptions: From 1987 through 2015 Ceroplastes stellifer was intercepted 251 times by CDFA’s high risk programs and dog teams. Interceptions have occurred on plants and fresh plant parts from Hawaii, Costa Rica, Ecuador, Jamaica, and Florida.

The risk Ceroplastes stellifer (stellate scale) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: The known distribution of Ceroplastes stellifer is primarily tropical and subtropical. The scale is expected to be able to establish throughout the warmer parts of California and receives a Medium (2) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Ceroplastes stellifer is known to feed on a wide variety of plants in at least 21 families. It receives a High (3) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Dispersal Potential: Scale insects have high reproductive rates and may disperse long distances when infested plants or plant parts are moved. They may also be spread by wind or by hitchhiking on plants, animals, or equipment. Ceroplastes stellifer receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: Ceroplastes stellifer is not documented reducing crop yields. It might reduce the value of nursery stock by disfiguring plants with its presence and increase crop production costs in nurseries and orchards. It is not expected to change cultural practices, vector other organisms, injure animals, or disrupt water supplies. Stellate scale receives a Medium (2) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Ceroplastes stellifer is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. It is not expected to feed on any threatened or endangered species or disrupt critical habitats. It might trigger new chemical treatments in orchards and the nursery industry and by residents who find infested plants unsightly. Host plants of the scale are common as ornamentals and in home gardens and might be significantly affected by this pest. Stellate scale receives a High (3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

**Consequences of Introduction to California for Ceroplastes stellifer (Stellate Scale): High (13**)

Add up the total score and include it here.

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Ceroplastes stellifer has not been found in California and receives a Not established (0) in this category.

–Not established (0) Pest never detected in California, or known only from incursions.

–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score

The final score is the consequences of introduction score minus the post entry distribution and survey information score: High (13)

Uncertainty:

There have not been any recent surveys for stellate scale. It could be present in some localities.

Conclusion and Rating Justification:

Ceroplastes stellifer has never been found in California and is likely to have significant economic and environmental impacts if it were to establish in the state. An “A” rating is justified.

References:

¹ Miller, Dug, Yair Ben-Dov, Gary Gibson, and Nate Hardy. ScaleNet. http://www.sel.barc.usda.gov/catalogs/coccidae/Ceroplastesstellifer.htm

http://scalenet.info/validname/Vinsonia/stellifera/

² USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

³Scale Insect Fact Sheet: Ceroplastes stillifer (Westwood). http://idtools.org/id/scales/factsheet.php?name=6919

⁴ Hodgson, Chris J. and Ana L.B.G. Peronti. 2012. A revision of the wax scale insects (Hemiptera: Sternorrhyncha: Coccoidea: Ceroplastinae) of the Afrotropical region. Zootaxa 3372: 265pp. http://www.mapress.com/zootaxa/list/2012/3372.html

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: A

Posted by ls

Hemiptera, Insects, Mites & Earthworms

Dysmicoccus texensis (Tinsley): A Mealybug

June 22, 2016 Jason Leathers

California Pest Rating for

Dysmicoccus texensis (Tinsley): A Mealybug

Hemiptera: Pseudococcidae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

Dysmicoccus texensis is regularly intercepted by CDFA and presently has a temporary rating of “Q”. A pest rating proposal is required to assign a permanent pest rating.

History & Status:

Background: Dysmicoccus texensis is a mealybug that is often found feeding on plant roots, where large populations prevent water and nutrient absorption, weaken plants, and reduce crop yields³. It is considered a pest of great pest importance on coffee in Brasil³(Rubiaceae: Coffea sp.¹). It has also been observed feeding, sometimes on aerial plant parts, on other hosts including: Anacardiaceae: Mangifera indica¹; Araceae: Dieffenbachia sp.¹; Bromeliaceae: Vriesea macrostachya¹; Euphorbiaceae: Manihot esculenta¹; Fabaceae: Acacia cornigera¹, Acacia veracruzensis¹, Acacia sphaerocephala¹, Acacia farnesiana¹, Inga inga¹, Inga ruiziana¹, Inga punctata¹, Inga laurina¹, Trifolium sp.¹; Malvaceae: Theobroma cacao¹, Theobroma amplexicaule¹, Meliaceae: Guarea sp.¹; Musaceae: Musa textilis¹, Musa paradisiaca¹; Myrtaceae: Psidium guajava¹; Polygonaceae: Coccoloba sp.¹; Rutaceae: Citrus latifolia¹; Citrus aurantium¹; Solanaceae: Solanum sp.¹. Coffee root mealybug may be transported long distances through commerce in infested plants or plant parts.

Worldwide Distribution: Dysmicoccus texensis is native to the Neotropical region including southern Texas, Mexico, Central America, and South America¹. It is also found in the Bahamas, Jamaica, Puerto Rico, Trinidad, and the U.S. Virgin Islands¹.

Official Control: Dysmicoccus texensis is not known to be under official control in any other states or nations².

California Distribution: Dysmicoccus texensis has never been found in the environment in California.

California Interceptions: Dysmicoccus texensis was intercepted 44 times by CDFA’s border stations, dog teams, and high risk programs between January 1, 2000 and December 31, 2014. The mealybug was found on limes, grapefruit, bananas, bell peppers, sugar apple, and aerial parts of unidentified plants.

The risk Dysmicoccus texensis (coffee root mealybug) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Host plants of Dysmicoccus texensis are commonly grown in California as both crops and ornamentals. Dysmicoccus texensis is likely to establish wherever hosts are grown. It receives a High (3) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Dysmicoccus texensis is known to feed on at least 24 species of plants in 13 families. It receives a Medium (2) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Dispersal Potential: Mealybugs have high reproductive rates and may be dispersed long distances by the movement of infested plants or fresh plant parts. They may also be dispersed locally by wind or by hitchhiking on clothing, equipment, or animals. Dysmicoccus texensis receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: Although known hosts of Dysmicoccus texensis include economically important crops such as Citrus and Solanum, it is primarily considered a pest of coffee. Yields of other crops are not likely to be significantly reduced. However, the mealybug may increase production costs in the nursery industry. It has potential to lower the value of nursery stock by disfiguring plants with its presence. Although D. texensis is not known to be considered a quarantine pest, several of California’s trading partners are significant producers of coffee. Since the mealybug is well documented as a serious pest of coffee, it is reasonable to expect that its presence could trigger disruptions of fresh fruit exports. Dysmicoccus texensis receives a Medium (2) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Dysmicoccus texensis is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. Trifolium is a host of D. texensis and several species of Trifolium are listed as threatened or endangered plants in California. These potential hosts include showy Indian clover (Trifolium amoenum), Pacific Grove clover (Trifolium polyodon), and Monterey clover (Trifolium trichocalyx). Dysmicoccus texensis is not expected to disrupt critical habitats. The mealybug may trigger new chemical treatments in orchards and the nursery industry. It is not expected to have significant impacts on cultural practices, home/urban gardening, or ornamental plantings. Dysmicoccus texensis receives a High (3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

**Consequences of Introduction to California for Dysmicoccus texensis: High (13)**

Add up the total score and include it here.

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Dysmicoccus texensis has never been found in the environment of California. It receives a Not established (0) in this category.

–Not established (0) Pest never detected in California, or known only from incursions.

–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score

The final score is the consequences of introduction score minus the post entry distribution and survey information score: High (13)

Uncertainty:

There have not been any recent surveys for Dysmicoccus texensis. It is possible that it could be present in some parts of the state.

Conclusion and Rating Justification:

Dysmicoccus texensis has never been found in the environment California. Its entry to the state is likely to have significant economic and environmental impacts. An “A” rating is justified.

References:

¹ Miller, Dug, Yair Ben-Dov, Gary Gibson, and Nate Hardy. ScaleNet. Dysmicoccus texensis is the valid name. http://scalenet.info/validname/Dysmicoccus/texensis/

²USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

³Neves, Pedro Manuel Oliveira Janeiro, Lenira Viana Costa Santa-Cecília, Jair Campos de Moraes, Luís Cláudio Paterno Silveira, and Alcides Moino Junior. 2006. Coffee root mealybug biology control entomopathogenic nematodes. Universidade Federal de Lavras. http://www.openthesis.org/documents/Biologics-aspects-Dysmicoccus-texensis-Tinsley-331392.html

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: A

Posted by ls

Hemiptera, Insects, Mites & Earthworms

Aleurodicus dispersus Russell (Spiraling Whitefly)

June 22, 2016 Jason Leathers

California Pest Rating for

Aleurodicus dispersus Russell (Spiraling Whitefly)

Hemiptera: Aleyrodidae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

In October 2013, USDA released a DEEP report proposing to deregulate Aleurodicus dispersus (spiraling whitefly). The insect is currently “Q”-rated by CDFA, so a pest rating proposal is needed to determine future direction.

History & Status:

Background: Spiraling whitefly is highly polyphagous, feeding on plants in 49 different plant families. Known hosts include such economically important pests as avocado, citrus, eggplant, pepper, rose, Prunus spp., and palms. Interceptions indicate that the whitefly often moves long distances in the trade of plants and flowers.

Worldwide Distribution: The native range of spiraling whitefly is believed to be the tropical Americas. It was described from Florida in 1965 from specimens collected as early as 1950. Since then it has been found to have a widespread distribution including Hawaii, Puerto Rico, the U.S. Virgin Islands, Guam, American Samoa, and Mexico. Furthermore, it is reported in numerous nations in Central America, the Caribbean, South America, Europe and the Middle East, Africa, Asia, and Oceania.

Official Control: Arizona has a state quarantine against all citrus whiteflies. Aleurodicus dispersus is also listed as a harmful organism by Antigua and Barbuda, Chile, China, French Polynesia, Grenada, Guatemala, Honduras, Israel, Japan, Jordan, Korea, Mexico, Morocco, and New Zealand².

California Distribution: Spiraling whitefly has not been found in the environment of California.

California Interceptions: Spiraling whitefly is frequently intercepted on shipments of plants, leaves, and flowers from Hawaii and Florida. It has been intercepted more than 1300 times since 11/29/2000.

The risk spiraling whitefly would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Spiraling whitefly has been present in Florida for over 60 years but has not spread beyond the central portion of the state. Primarily a tropical species, it is reportedly limited by cold temperatures. In California the whitefly would likely be limited to southern and coastal areas. Spiraling whitefly receives a Medium (2) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Spiraling whitefly is a highly polyphagous insect that is known to feed on plants from 49 different plant families. The whitefly receives a High(3) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Dispersal Potential: Whiteflies reproduce rapidly and can be spread long distances by wind or through the movement of plants and flowers. Spiraling whitefly receives a High(3) in this category.

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: Spiraling whitefly was originally considered an economic pest in Hawaii when it was introduced. However, damage is now limited as a successful biological control agent was introduced. In the absence of this biological control agent in California, the whitefly may be expected to lower crop yield by both sucking juices from plants and reducing their photosynthetic capacity by contaminating leaf surfaces with sooty mold. They may also lower crop value by triggering treatment and/or disfiguring nursery stock with their presence and with sooty mold. Furthermore, Arizona maintains a quarantine against all citrus whiteflies and many of California’s trading partners list Aleurodicus dispersus as a harmful organism. This could lead to disruptions in markets for California citrus. Spiraling whitefly receives a High(3) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Rosa minutafolia (small-leaved rose) is listed as an endangered species in California and is a potential host for spiraling whitefly. The whitefly may also trigger additional chemical treatments. The whitefly receives a High(3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

**Consequences of Introduction to California for Aleurodicus dispersus (Spiraling Whitefly): High(14)**

Add up the total score and include it here.

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Spiraling whitefly has not been found in the environment of California. It receives a Not established(0) in this category.

–Not established (0) Pest never detected in California, or known only from incursions.

–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score

The final score is the consequences of introduction score minus the post entry distribution and survey information score: High(14)

Uncertainty:

Spiraling whitefly has been intercepted more than a thousand times in California. However, it has never been found in the environment. This may indicate that environmental conditions in the state are unfavorable for establishment of the species.

Conclusion and Rating Justification:

In the absence of a successful biological control program in California, spiraling whitefly is expected to have significant economic and environmental impacts. An “A”-rating is justified.

References:

¹Zlotina, Marina 2013. Deregulation Evaluation of Established Pests (DEEP); DEEP Report on Aleurodicus dispersus Russell: Spiralling Whitefly

² USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: A

Posted by ls

Gastropoda, Snails and Slugs

Chinese Slug | Meghimatium bilineatum (Benson)

June 21, 2016 Jason Leathers

California Pest Rating for

Chinese Slug | Meghimatium bilineatum (Benson)

Gastropoda: Philomycidae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

Meghimatium bilineatum has been intercepted by CDFA’s high risk programs, border stations, and dog teams and presently has a temporary rating of “Q”. A pest rating proposal is required to assign a permanent pest rating.

History & Status:

Background: Meghimatium bilineatum is a terrestrial slug that lives in humid environments beneath plants and emerges to forage after rainfall¹. It is also found on cultivated land, landscaped urban areas, smooth-barked live trees, rocks, and under dead logs². Like other slugs Meghimatium bilineatum is presumably polyphagous on a wide variety of living and decaying plants. The slug may be transported long distances on nursery stock.

Worldwide Distribution: Meghimatium bilineatum is native to the mid and lower Yangtse basin of China¹. From there it has spread to Taiwan, Japan, Hawaii, Java, and Russia². Interceptions by CDFA on consignments from Florida and Ecuador indicate that it could be more widespread.

Official Control: Meghimatium bilineatum is not known to be under official control in any other states or nations³.

California Distribution: Meghimatium bilineatum has never been found in the environment of California.

California Interceptions: CDFA has intercepted Meghimatium bilineatum 16 times on nursery stock and ti leaves from Hawaii, Ecuador, and Florida.

The risk Meghimatium bilineatum would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Meghimatium bilineatum is a polyphagous terrestrial slug and is likely able to establish anywhere suitable moisture is available in California. It receives a High (3) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Meghimatium bilineatum is presumably polyphagous on a wide variety of living and decaying plants. It receives a High (3) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Dispersal Potential: Females of Meghimatium bilineatum may live up to four years in the laboratory and produce an average of 932 eggs, indicating a high reproductive rate. The slugs may be transported long distances when infested nursery stock is moved. Meghimatium bilineatum receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: Meghimatium bilineatum does not appear to be documented as an agricultural pest and is therefore not expected to lower crop yields. However, slugs have the potential to significantly reduce the value of nursery stock by feeding on plants and contaminating them with their presence. The slugs are not expected to interfere with markets or change cultural practices. Meghimatium bilineatum has been documented as a vector of rat lungworm⁴. The slugs are not expected to injure animals or interfere with water supplies. Meghimatium bilineatum receives a Medium (2) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Meghimatium bilineatum is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. It is not expected to directly affect threatened or endangered species or disrupt critical habitats. It may trigger additional treatment programs in the nursery industry and by residents who find infested plants or garden unacceptable. It is not expected to significantly impact cultural practices, home/urban gardening, or ornamental plantings. Meghimatium bilineatum receives a Medium (2) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

Consequences of Introduction to California for Meghimatium bilineatum: High (13)

Add up the total score and include it here.

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Meghimatium bilineatum has never been found in California and receives a Not established (0) in this category.

–Not established (0) Pest never detected in California, or known only from incursions.

–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score

The final score is the consequences of introduction score minus the post entry distribution and survey information score: High (13)

Uncertainty:

There have not been any recent comprehensive slug surveys in California. It is possible that Meghimatium bilineatum could be present in some localities.

Conclusion and Rating Justification:

Meghimatium bilineatum has never been found in the environment of California and may have significant economic and environmental impacts if it were to establish here. An “A” rating is justified.

References:

¹ Wiktor, Andrzej, Chen De-Niu, and Wu Ming. 2000. Stylommatophoran Slugs of China (Gastropoda: Pulmonata) – Prodromus. Folia Malacologica 8(1): 3-35. http://agro.icm.edu.pl/agro/element/bwmeta1.element.agro-e16e8da9-fe23-46f1-9334-cd9a90234311/c/FM08_1__2_1_.pdf

² Paustian, Megan. Terrestrial Slugs Web. http://terrslugs.lifedesks.org/pages/31161

³ USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

⁴ Molet, T. 2014. CPHST Pest Datasheet for Meghimatium pictum. USDA-APHIS-PPQ-CPHST. https://caps.ceris.purdue.edu/webfm_send/2556

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

Pest Rating: A

Posted by ls

Hemiptera, Insects, Mites & Earthworms

Pseudaulacaspis cockerelli (Cooley): Magnolia White Scale

June 21, 2016 Jason Leathers

California Pest Rating for

Pseudaulacaspis cockerelli (Cooley): Magnolia White Scale

Hemiptera: Diaspididae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

Pseudaulacaspis cockerelli is frequently intercepted by CDFA and requires a pest rating proposal to support its pest rating.

History & Status:

Background: Pseudaulacaspis cockerelli is a highly polyphagous armored scale insect that is a pest of many ornamental plants in the nursery industry¹. The scales live on the upper and lower leaf surfaces and green stems of plants². Infestations can cause loss of vigor, spots on foliage, deformation of infested plant parts, loss of leaves, and may lead to death of plants². Known hosts include: Actinidiaceae: Actinidia spp.^3,4; Adoxaceae: Viburnum sp.^3,4; Agavaceae: Yucca sp.³; Amaryllidaceae: Agapanthus sp.^3,4, Eurycles sp.^3,4; Anacardiaceae: Anacardium occidentale^3,4, Campnosperma brevipetiolata^3,4, Mangifera indica^3,4, Mangifera sp.^3,4; Annonaceae: Annona squamosa^3,4, Artabotrys hexapetutus³, Canangium odoratum^3,4; Apocynaceae: Adenium sp.^3,4, Allamanda sp.^3,4, Alyxia olivaeformis^3,4, Calotropis gigantea⁴; Nerium indicum^3,4, Nerium oleander^3,4, Nerium sp.^3,4, Plumeria acuminata^3,4, Plumeria acutifolia^3,4, Plumeria sp.^3,4, Thevetia peruviana^3,4, Trachelospermum asiaticum^3,4, Trachelospermum jasminoides^3,4, Trachelospermum sp.^3,4, Willughbeia sp.^3,4; Aquifoliaceae: Ilex cinerea³, Ilex crenata^3,4, Ilex integra^3,4, Ilex latifolia^3,4, Ilex sp.^3,4, Ilex viridis³; Araceae: Acorus gramineus^3,4, Alocasia sp.^3,4, Philodendron sp.^3,4; Araliaceae: Fatsia japonica^3,4, Hedera canariensis^3,4, Hedera helix^3,4, Hedera rhombea^3,4; Arecaceae: Archontophoenix alexandrae^3,4, Areca catechu^3,4, Areca sp.^3,4, Arecastrum romanzoffianum^3,4, Arenga engleri^3,4, Butia capitata^3,4, Caryota sp.^3,4, Chamaerops humilis^3,4, Chrysalidocarpus dictyospermi^3,4, Chrysalidocarpus lutescens^3,4, Chrysalidocarpus sp.^3,4, Clinostigma savoryana^3,4, Clinostigma sp.^3,4, Cocos nucifera^3,4, Cocos sp.^3,4, Corypha elata^3,4, Elaeis sp.^3,4, Howeia sp.^3,4, Livistona sp.^3,4, Neodypsis baroni^3,4, Nipa fruticans^3,4, Phoenix roebelenii^3,4, Rhapis humilis^3,4, Sabal mexicana^3,4, Seaforthia sp.^3,4, Serenoa repens^3,4, Trachycarpus sp.^3,4; Asclepiadaceae: Calotropis gigantean³; Asparagaceae: Asparagus sp.^3,4, Dracena sp.⁴, Yucca sp.⁴; Asteraceae: Helianthus annuus^3,4, Helianthus sp.^3,4, Pyrrhopappus carolinianus^3,4; Berberidaceae: Nandina domestica^3,4; Bignoniaceae: Tabebuia pentaphylla^3,4; Bromeliaceae: Bromelia sp.^3,4, Vriesea sp.^3,4; Burseraceae: Canarium album³; Buxaceae: Buxus sp.^3,4; Cannaceae: Canna generalis^3,4; Caprifoliaceae: Viburnum arboricolum^3,4; Viburnum awabuki^3,4, Viburnum odoratissimum^3,4, Weigela sp.^3,4; Caricaceae: Carica papaya^3,4; Celastraceae: Euonymus sacrosancta^3,4, Schaefferia sp.^3,4; Clusiaceae: Calophyllum inophyllum^3,4; Combretaceae: Terminalia catappa^3,4; Cornaceae: Aucuba japonica^3,4, Cornus controversa^3,4, Cornus florida^3,4; Crassulaceae: Bryophyllum sp.^3,4; Cycadaceae: Cycas circinalis^3,4, Cycas revoluta^3,4, Cycas sp.^3,4, Zamia floridana^3,4, Zamia sp.^3,4; Daphniphyllaceae: Daphniphyllum sp.^3,4; Ebenaceae: Diospyros lotus^3,4, Diospyros sp.^3,4; Elaeocarpaceae: Elaeocarpus decipiens^3,4, Elaeocarpus photiniaefolius^3,4; Ericaceae: Chimaphila maculata^3,4, Rhododendron sp.^3,4; Euphorbiaceae: Aleurites moluccana^3,4, Aleurites sp.^3,4, Bischofia javanica^3,4, Daphniphyllum glaucescens^3,4, Daphniphyllum macropodum^3,4, Daphniphyllum teijsmanni^3,4, Euphorbia humistrata^3,4, Excoecaria orientalis^3,4, Hevea brasiliensis^3,4, Hevea sp.^3,4, Jatropha hastata^3,4, Sapium sebiferum^3,4; Fagaceae: Lithocarpus sp.^3,4; Garryaceae: Aucuba sp.^3,4; Gnetaceae: Gnetum luofuerise³; Hamamelidaceae: Liquidambar formosana^3,4; Heliconiaceae: Heliconia sp.^3,4; Hemerocallidaceae: Dianella sp.³; Hippocastanaceae: Aesculus turbinate³; Hydrangeaceae: Deutzia scabra crenata^3,4; Iridaceae: Iris sp.^3,4, Moraea bicolor^3,4; Lardizabalaceae: Akebia lobata^3,4, Akebia quinata^3,4, Akebia trifoliate^3,4; Lauraceae: Machilus kobu^3,4, Persea americana^3,4; Lecythidaceae: Barringtonia speciose^3,4; Liliaceae: Cordyline terminalis^3,4, Dianella ensifolia^3,4, Dianella montana^3,4, Dianella tasmanica^3,4, Liriope muscari^3,4, Nolina sp.^3,4, Phormium tenax^3,4, Sansevieria nilotica^3,4, Yucca gloriosa^3,4, Yucca recurvifolia^3,4; Loganiaceae: Fagraea berteriana^3,4; Loranthaceae: Dendrophthoe falcate³, Ettingsh sp.³; Magnoliaceae: Magnolia denudata^3,4, Magnolia grandiflora^3,4, Magnolia kobus^3,4, Magnolia officinalis^3,4, Magnolia soulangeana^3,4, Magnolia sp.^3,4, Magnolia virginiana^3,4, Michelia alba^3,4, Michelia champaca^3,4, Michelia compressa^3,4, Michelia figo^3,4, Michelia fuscata^3,4, Michelia sp.^3,4, Schizandra chinensis^3,4; Malvaceae: Hibiscus sp.^3,4; Marantaceae: Clinogyne virgata^3,4; Melastomaceae: Melastoma sp.^3,4; Meliaceae: Aglaia odorata^3,4; Moraceae: Ficus carica^3,4, Ficus microcarpa³, Ficus pumila^3,4, Ficus sp.^3,4, Ficus wightiana^3,4, Morus alba^3,4, Morus sp.^3,4; Musaceae: Musa paradisiaca^3,4, Musa sp.^3,4, Strelitzia nicolai^3,4, Strelitzia reginae^3,4; Myristicaceae: Myristica fragrans^3,4, Myristica laurifolia^3,4, Myristica moschata^3,4, Myristica sp.^3,4; Myrtaceae: Callistemon sp.^3,4, Eugenia^3,4, Pimenta officinalis^3,4, Syzigium eumini³; Oleaceae: Olea sp.^3,4, Osmanthus fragrans^3,4, Syringa amurensis^3,4; Pandanaceae: Pandanus odoratissimus^3,4; Phyllanthaceae: Bischofia sp.^3,4; Poaceae Bambusa sp.^3,4; Podocarpaceae: Podocarpus nagi^3,4; Polygonaceae: Polygonum spp.^3,4; Pteridophyta: Adiantum sp.^3,4; Rhizophoraceae: Rhizophora mangle^3,4, Rhizophora sp.^3,4; Rosaceae: Prunus padus^3,4; Rubiaceae: Adina rubella^3,4, Gardenia jasminoides^3,4, Gardenia sp.^3,4, Ixora coccinea³; Ruscaceae: Dracaena sp.³; Rutaceae: Calodendrum spp.^3,4, Citrus sp.^3,4; Sarraceniaceae: Sarracenia purpurea^3,4; Saxifragaceae: Deutzia sp.^3,4, Ribes sp.^3,4; Solanaceae: Capsicum annuum^3,4; Strelitziaceae: Ravenala madagascariensis^3,4, Strelitzia sp.^3,4; Symplocaceae: Symplocos ramosissima^3,4; Taxaceae: Taxus cuspidata^3,4, Taxus sp.^3,4, Torreya sp.^3,4; Theaceae: Camellia japonica^3,4, Camellia oleifera^3,4, Camellia sasanqua^3,4, Camellia sinensis^3,4, Camellia sp.^3,4, Eurya acuminata^3,4, Eurya crenatifolia^3,4, Eurya japonica^3,4, Eurya strigillosa^3,4, Thea sinensis^3,4; Trochodendraceae: Trochodendron aralioides^3,4; Ulmaceae: Aphananthe sp.^3,4; Verbenaceae: Stachytarpheta jamaicensis^3,4; Xanthorrhoeaceae: Dianella sp.⁴; Uncertain: Zorisma ovalifolia^3,4. Pseudalacaspis cockerelli may be transported long distances when infested plants or fresh plant parts are moved.

Worldwide Distribution: Pseudaulacaspis cockerelli is probably native to Asia². From there it has spread throughout much of the world^3,4. It was first found in Hawaii in 1898² and Florida in 1942¹. Within the continental United States it is now considered widespread in the Gulf States and Georgia¹.

Official Control: Pseudaulacaspis cockerelli is listed as a harmful organism by Chile, Costa Rica, Ecuador, Guatemala, Japan, Mexico, New Zealand, Panama, and Peru⁵.

California Distribution: Pseudaulacaspis cockerelli has not been found in the environment of California.

California Interceptions: Pseudaulacaspis cockerelli is regularly found by CDFA’s high risk inspections, border stations, dog teams, and nursery inspections. Between January 1, 2000 and December 31, 2014 the scale was intercepted 2,187 times, typically on nursery stock and fresh plant parts from Florida and Hawaii.

The risk Pseudaulacaspis cockerelli (magnolia white scale) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Pseudaulacaspis cockerelli is highly polyphagous and is likely to find suitable hosts throughout California and establish a widespread distribution in the state. It receives a High (3) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Pseudaulacaspis cockerelli feeds on hundreds of species of plants in at least 81 families. It receives a High (3) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Dispersal Potential: Scale insects are capable of rapid reproduction and can be transported long distances when infested plants or fresh plant parts are moved. They may also disperse locally by crawling, wind, or by hitchhiking on clothing, equipment, or animals. Pseudaulacaspis cockerelli receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: Pseudaulacaspis cockerelli is likely to reduce the value of nursery stock by disfiguring plants with its presence. It is also likely to increase production costs by triggering new management programs. The scale is also considered a quarantine pest by several of California’s trading partners. Its presence in the state may disrupt markets for nursery stock and fresh fruit. Pseudaulacaspis cockerelli receives a Medium (2) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Pseudaulacaspis cockerelli is likely to trigger additional treatment programs in the nursery industry and by residents who find infested plants unsightly. The scale insect is also likely to significantly affect many ornamental plantings. It receives a High (3) rating in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

Consequences of Introduction to California for Pseudaulacaspis cockerelli (Magnolia White Scale): High (14)

Add up the total score and include it here.

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Pseudaulacaspis cockerelli has not been found in the environment of California and receives a Not established (0) in this category.

–Not established (0) Pest never detected in California, or known only from incursions.

–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score

The final score is the consequences of introduction score minus the post entry distribution and survey information score: High (14)

Uncertainty:

Pseudaulacaspis cockerelli is frequently intercepted by CDFA. Presumably, it enters California at other times undetected. It is possible that it has been introduced and is established in some localities. Alternatively, it could be failing to establish.

Conclusion and Rating Justification:

Pseudaulacaspis cockerelli has not been found in California and is expected to have significant economic and environmental impacts if it were to establish in the state. An “A” rating is justified.

References:

¹ Hamon, Avas B. 2015. University of Florida Featured Creatures. Common name: false oleander scale. http://entnemdept.ufl.edu/creatures/orn/scales/false_oleander_scale.htm

² Tenbrink, Victoria L. and Arnold H. Hara. 1992. Hawaii Crop Knowledge Master: Pseudaulacaspis cockerelli (Cooley). http://www.extento.hawaii.edu/kbase/crop/Type/p_cocker.htm

³ SEL Catalog.

⁴ Miller, Dug, Yair Ben-Dov, Gary Gibson, and Nate Hardy. ScaleNet.

http://scalenet.info/catalogue/Pseudaulacaspis%20cockerelli/

http://scalenet.info/validname/Pseudaulacaspis/cockerelli/

⁵ USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

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Pest Rating: A

Posted by ls

Fungi, Plant Pathogens

Phytophthora quercina T. Jung 1999

June 21, 2016 Admin

California Pest Rating for

Phytophthora quercina T. Jung 1999

Pest Rating: B

PEST RATING PROFILE

Initiating Event:

On April 25, 2016, two soil samples with roots of valley oak (Quercus lobata) trees that showed symptoms of stunting in a restoration site in Santa Clara County, were collected by Santa Clara County Agricultural officials and sent to the CDFA Plant Pathology Laboratory, for diagnosis. DNA was extracted from soil baits and determined to be 100% similar to the pathogen, Phytophthora quercina, by Suzanne Rooney-Latham, CDFA plant pathologist. DNA samples were sent by CDFA to the USDA APHIS PPQ CPHST Laboratory in Beltsville, Maryland, and on June 10, 2016, USDA confirmed the identity of P. quercina. This detection marked the first confirmed presence and new record of the pathogen in the United States (USDA APHIS PPQ, 2016). Currently, P. quercina has a temporary ‘Q’ rating in California. The risk of introduction and establishment of this pathogen in California is assessed and a permanent rating is proposed herein.

History & Status:

Background: Oak decline is a serious and frequently recurring disease in Europe since the beginning of the twentieth century (Jung et al., 1999). During the early 1990s, several Phytophthora spp. including a newly described P. quercina were found to be associated with oak decline and root rot in central and southern Europe. In pathogenicity tests on oak, Quercus robur, P. quercina was found to be most pathogenic in comparison to the other associated Phytophthora species (Jung et al., 1999). Subsequent reports associated P. quercina with oak decline from Turkey, Austria, and Italy (Balcý & Halmschlager, 2002a, 2002b; Vettraino et al., 2002). Phytophthora quercina is an oomycete, and Cooke et al, (1999) provided molecular evidence that verified P. quercina as a distinct species.

Phytophthora quercina was recently detected in soil samples obtained from the root zone area of diseased valley oak trees grown at a California restoration site. The USDA marked this detection as the first known confirmation of the pathogen in the United States. Details are given above in “Initiating Event”. The species was reported in 2007 on being detected in a soil bait around a declining oak tree in Central Missouri (Schwingle et al., 2007), however, the identification was not confirmed by USDA APHIS and there have not been any further publications on the species in the USA (USDA APHIS PPQ, 2016).

Hosts: Quercus spp. (oak): Q. cerris, Q. hartwissiana, Q. frainetto, Q. ilex, Q. robur, Q. petraea, Q. pubescens, Q. suber, and Q. vulcanica (Balcý & Halmschlager, 2002a, 2002b; EPPO, 2016; Farr & Rossman, 2016; NPRG, 2010).

Symptoms: Phytophthora quercina, along with several other Phytophthora species, occur in oak decline stands in Europe (Balcý & Halmschlager, 2002; Jung et al., 2008). Above ground symptoms of oak decline include dieback of branches and parts of the crown, formation of epicormic shoots, high transparency of the crown, yellowing and wilting of leaves and tarry exudates from the bark. These symptoms are indicative of water stress and poor nutrition (Jung et al., 2008). Below ground symptoms in declining European oak species resulted in deterioration of oak fine roots, including a progressive destruction of the fine root system, dieback of long roots, and necrotic lesions on suberized and non-suberized roots. Although these symptoms occur in both healthy and declining oaks, the damage is generally more severe in declining oaks (Jung, et al., 2008). The pathogen also causes abnormal root branching, and produces elicitins, viz. toxic substances that induce wilting and yellowing and leaf necrosis in declining oaks (NPRG, 2010). In pathogenicity test, P. quercina-infected Quercus robur (oak) seedlings with severe root rot showed wilting and necrosis of leaves, root necrosis and dieback of the shoot. Under natural conditions, mature Q. robur trees showed reductions in fine root length (Jung et al., 1999).

Damage Potential: The extent of damage caused by Phytophthora quercina has not been reported. Several Phytophthora species including P. quercina are associated with oak decline disease. However, P. quercina has been shown to be pathogenic to some European Quercus species, such as Q. robur (Jung et al., 1999), and to be one of the most aggressive and most common species found in reported surveys in Europe (Jung et al., 1999, 2008; Balcý and Halmschlager 2002a, 2002b). In Italy, P. quercina was the only species significantly associated with declining oak trees (Vettraino et al., 2002).

Disease Cycle: Although present in roots and rhizosphere soil of oaks exhibiting symptoms of oak decline, the precise role of Phytophthora quercina in this disease is not known and very little is known about its biology. Jung et al. (2008), reported that at least two different complex diseases are referred to as ‘oak decline’. On sites with a mean soil pH 3.5 or greater and sandy-loam to clayey soil texture, Phytophthora species were commonly isolated from rhizosphere soil, and highly significant correlations existed between crown transparency and various root parameters. However, in sites with a mean soil pH less than 3.9 and sandy to sandy-loam soils, Phytophthora species were not found. Biotic and abiotic stress factors such as drought and frost, may often act synergistically and accelerate Phytophthora-mediated decline of oaks.

Generally, species of Phytophthora that cause root and stem rots survive cold winters or hot and dry summers as thick-walled, resting spores (oospores and chlamydospores) or mycelium in infected roots, stems or soil. During spring, the oospores and chlamydospores germinate to produce motile spores (zoospores) that swim around in soil water and roots of susceptible hosts. The pathogen infects the host at the soil line causing water soaking and darkening of the trunk bark. This infected area enlarges and may encircle the entire stem of small plants which wilt and eventually die. On large plants, the infected, necrotic area may be on one side of the stem and become a depressed canker below the level of the healthy bark. Collar rot canker may spread down the root system. Roots are invaded at the crown area or at ground level. Mycelium and zoospores grow in abundance in cool, wet weather causing damage where the soil is too wet for normal growth of susceptible plants and low temperatures (15-23°C) prevail (Agrios, 2005). Phytophthora quercina is homothallic. Optimum growth in culture is at 20°C and 25°C, however, it is able to grow at temperatures as high as 27.5°C (Jung et al., 1999; Barzanti et al., 2001).

Transmission: Like most Phytophthora species, P. quercina is soil-borne and water-borne and may be spread to non-infected sites through infected plants, nursery and planting stock, and seedlings, soil, run-off and splash irrigation and rain water, and contaminated cultivation equipment, tools, and boots.

Worldwide Distribution: Asia: Turkey; Europe: Austria, Belgium, France, Germany, Hungary, Italy, Luxemberg, Montenegro, Serbia, Spain, Sweden, Scotland, United Kingdom: North America: USA (California) (Balcý & Halmschlager, 2002a, 2002b; EPPO, 2016; Farr & Rossman, 2016; Jung et al., 1999; NPRG, 2010).

Official Control: Phytophthora quercina is listed as an exotic forest pathogen in USDA APHIS PPQ Federal New Pest Response Guidelines for Phytophthora species (NPRG, 2010). The species has been on the North American Plant Protection Organization (NAPPO) alert list since 2002. Currently, P. quercina has a temporary ‘Q’ rating in California.

California Distribution: Phytophthora quercina has been detected in a California native plant restoration site in a Santa Clara County.

California Interceptions: None.

The risk that Phytophthora quercina would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Evaluate and score the pest for suitability of hosts and climate to establish in California. Score:

– Low (1) not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

Risk is High (3) – Although Phytophthora quercina has been reported to be associated primarily with European oak species in Europe, its recent detection in valley oak rhizosphere soil extends the capability of this pathogen to be associated with California native oaks. Valley oak is endemic to California and present throughout the State. Thereby, making it likely for the pathogen to establish a widespread distribution in California. It is not yet known, but probable that other California native oaks may be affected by P. quercina.

2) Pest Host Range: Evaluate and score the pest as it pertains to host range. Score:

– Low (1) has a very limited host range

– Medium (2) has a moderate host range

– High (3) has a wide host range

Risk is Low (1) – Phytophthora quercina has a host range limited to Quercus spp. that includes Q. cerris, Q. hartwissiana, Q. frainetto, Q. ilex, Q. robur, Q. petraea, Q. pubescens, Q. suber, and Q. vulcanica. In California, it was found to be associated with Q. lobata.

3) Pest Dispersal Potential: Evaluate and score the pest for dispersal potential using these criteria. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

Risk is High (3) – Phytophthora quercina is soil-borne and water-borne and therefore, primarily spread artificially via infested soils, plants, nursery and planting stock, seedlings, run-off and splash irrigation water, cultivation equipment and tools, and boots that may spread contaminated soil and plant materials to non-infected sites.

4) Economic Impact: Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

Risk is Medium (2) – The extent of damage caused by Phytophthora quercina has not been reported. Several Phytophthora species including P. quercina are associated with oak decline disease. In Europe, P. quercina was most commonly associated with the disease than were other Phytophthora species. The pathogen could impact nursery-produced oaks thereby triggering possible loss of markets and requiring changes in normal cultural practices to avoid spread of the soil and water-borne pathogen.

5) Environmental Impact: Evaluate the environmental impact of the pest on California using the criteria below. Score:

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species

C. The pest could impact threatened or endangered species by disrupting critical habitats

D. The pest could trigger additional official or private treatment programs,

E. The pest could significantly impact cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact:

– Low (1) causes none of the above to occur

– Medium (2) causes one of the above to occur

– High (3) causes two or more of the above to occur

Risk is High (3) – Phytophthora quercina is listed as an exotic forest pathogen in USDA APHIS PPQ Federal New Pest Response Guidelines for Phytophthora species (NPRG, 2010). The species has been on the North American Plant Protection Organization (NAPPO) alert list since 2002. Although the extent of damage potentially caused by this pathogen is not yet known, its spread within California could cause serious impact on native oaks, disrupt critical habitats by killing critical species necessary for species diversity and soil stability, necessitate official or private treatment programs to preserve critical, rare, or endangered species, and significantly impact cultural practices, home/urban and/or ornamental plantings.

**Consequences of Introduction to California for Phytophthora quercina:**

Add up the total score and include it here

Low = 5-8 points

Medium = 9-12 points

High = 13-17 points

Total points obtained on evaluation of consequences of introduction of Phytophthora quercina to California = (12).

6) Post Entry Distribution and Survey Information: Evaluate the known distribution in California. Only official records identified by a taxonomic expert and supported by voucher specimens deposited in natural history collections should be considered. Pest incursions that have been eradicated, are under eradication, or have been delimited with no further detections should not be included. (Score)

-Not established (0) Pest never detected in California, or known only from incursions.

-Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

-Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

-High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Evaluation is Low (-1).

Final Score

The final score is the consequences of introduction score minus the post entry distribution and survey information score: (Score)

Final Score: Score of Consequences of Introduction – Score of Post Entry Distribution and Survey Information = 11.

Uncertainties:

The extent of economic damage caused by Phytophthora quercina is not known. Also not known is the exact role of the pathogen in oak decline disease, and details of the biology of the pathogen species.

Conclusion and Rating Justification:

Based on the evidence provided above the proposed rating for Phytophthora quercina is B.

References:

Agrios, G. N. 2005. Plant Pathology fifth edition. Elsevier Academic Press, Massachusetts, USA. 922 p.

Balcý, Y. and E. Halmschlager. 2002a. First confirmation of Phytophthora quercina on oaks in Asia. Plant Disease 86:442. http://dx.doi.org/10.1094/PDIS.2002.86.4.442C

Balcý, Y. and E. Halmschlager. 2002b. First report of Phytophthora quercina in Austria. New Disease Reports volume 6, August 2002-January 2003. http://www.bspp.org.uk/ndr/jan2003/2002-28.htm

Barzanti, G. P., P. Capretti, and A. Ragazzi. 2001. Characteristics of some Phytophthora

species isolated from oak forest soils in central and northern Italy.

Phytopathologia Mediterranea 40(2): 149-156.

Cooke, D.E.L., T. Jung, N. A. Williams, R. Schubert, G. Bahnweg, W. Oswald, and J. M. Duncan. 1999. Molecular evidence supports Phytophthora quercina as a distinct species. Mycological Research, 103:799-804.

EPPO. 2016. Phytophthora quercina (PHYTQU). New PQR database. Paris, France: European and Mediterranean Plant Protection Organization. http://newpqr.eppo.int

Farr, D.F., & A. Y. Rossman. Fungal Databases, Systematic Mycology and Microbiology Laboratory, ARS, USDA. Retrieved January 28, 2016, from http://nt.ars-grin.gov/fungaldatabases/

Jung, T., D. E. L. Cooke, H. Blaschke, J. M. Duncan, and W. Oswald. 1999. Phytophthora quercina sp. nov., causing root rot of European oaks. Mycol. Res. 103: 785-798.

Jung, T., H. Blaschke and W. Oßwald. 2008. Involvement of soilborne Phytophthora species in Central European oak decline and the effect of site factors on the disease. Plant Pathology, 49:706-718. DOI: 10.1046/j.1365-3059.2000.00521.x

Schwingle, B. W., J. Juzqik, J. Eggers, and B. Moltzan. 2007. Phytophthora species in soils associated with declining and nondeclining oaks in Missouri Forests. Plant Disease 91:633. http://apsjournals.apsnet.org/doi/abs/10.1094/PDIS-91-5-0633A

NPRG. 2010. New Pest Response Guidelines: Phytophthora species in the Environment and Nursery Settings. USDA MRP APHIS PPQ Cooperating State Departments of Agriculture, July 09 2010. 229 pages.

USDA APHIS PPQ. 2016. Email from J. H. Bowers, National Survey Coordinator National Policy Manager, Cooperative Agricultural Pest Survey, USDA, APHIS, PPQ, PHP, to Nick Condos, Director, CDFA, sent Friday, June 10, 2016, 11:56 am.

Vetrraino, A. M., G. P. Barzanti, M. C. Bianco, A. Ragazzi, P. Capretti, E. Paoletti, N. Luisi, N. Anselmi, and A. Vannini. 2002. Occurrence of Phytophthora species in oak stands in Italy and their association with declining oak trees. Forest Pathology, 32:19-28. DOI: 10.1046/j.1439-0329.2002.00264.x

Responsible Party:

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: B

Posted by ls

Nematodes

Pratylenchus thornei Sher & Allen, 1953

June 2, 2016 Admin

California Pest Rating for

Pratylenchus thornei Sher & Allen, 1953

Pest Rating: C

PEST RATING PROFILE

Initiating Event:

During the 1950-60s, several species of plant parasitic nematodes were given a ‘D’ rating as they were regarded as parasites, predators or organisms of little or no economic importance that did not require State enforced regulatory action. However, these nematode species were inaccurately assigned a D rating as most, if not all, are plant parasitic and therefore, capable of damaging plant production and causing significant economic losses especially at the county and local residential/grower level. Furthermore, the detection of plant parasitic nematodes in nursery stock may be an indication of contamination in violation of the State’s standard of pest cleanliness required for nurseries. Pratylenchus thornei was originally rated D and its risk of infestation and permanent rating are re-assessed here.

History & Status:

Background: The root lesion nematode, Pratylenchus thornei, was first reported from soil around the roots of grass at Berkeley, California (Sher & Allen, 1953). Since then, P. thornei has been found to be associated with a variety of plants in different geographic locations and is a serious parasite of wheat in Utah, Australia, Yugoslavia, India, Italy, and Mexico (Fortuner, 1977). The host status of associated plants is not always known. Pratylenchus thornei is one of the most widely distributed species of Pratylenchus and has been reported from every continent except Antarctica (Castillo & Vovlas, 2007). In California, P. thornei is widely distributed statewide, even though it is known to prefer temperate soils (CABI, 2016).

Pratylenchus thornei, is an obligate migratory endoparasite that first feeds externally then enters plant roots, feeds, reproduces and moves freely within the tissue while spending its entire life cycle there. The species can also be found in soil around roots. Within the roots, feeding is confined to the root cortex. Like other Pratylenchus species, P. thornei has six life stages: egg, four juvenile stages and adults. Reproduction is by parthenogenesis (without fertilization). First stage juveniles develop within the egg, followed by a first molt to the second stage juvenile that hatches from the egg. Each stage develops into the next via a molt of its cuticle (outer body covering). All juvenile and adult stages are worm-shaped (vermiform). All post-hatch stages are motile and can infect plants. The time to complete a life cycle is dependent on temperature and moisture. The life cycle of P. thornei was completed in about 25-35 days on carrot discs at 20-25°C (Castillo et al., 1995) and about 25-29°C on corn at 30°C (Siyanand et al., 1982). Pratylenchus thornei survives the winter in infected roots or soil as eggs, juveniles or adults. Under experimental conditions, survival of P. thornei in 200 g soil samples was reduced by drying to 5% moisture content and at 40°C was killed in less than 2 weeks, perhaps due to loss of moisture. The nematodes become inactive at freezing to – 5°C Fortuner, 1977). During spring, when plant growth is active, eggs hatch, nematodes are attracted to the plant roots and begin to feed and continue their life cycle within roots or in rhizosphere soil. Within the root, the nematode feeds on cortical tissue causing necrosis of cortical cells, cell breakdown, and formation of cavities. Necrosis is apparent as lesions which expand as the nematodes move lengthwise within the infected roots. Some nematodes may leave the root, enter soil and re-enter the root at a different site causing a new infection.

Hosts: Pratylenchus thornei is an important root parasite primarily of wheat and other cereals such as, barley and maize. The nematode species has been associated with different plants from several countries. The host status of associated plants is not always known. Nevertheless, hosts/associated plants include, cereals, wheat, durum wheat, barley, chickpea, corn, oats, sorghum, tobacco, carrot, celery, globe artichoke, asparagus, broccoli, cabbage, cauliflower, olive, onion, cotton, potato, strawberry, tomato, tea, ginger, strawberry clover, berseem clover, white clover, soybean, leguminous plants, sweet pea, lentil, alfalfa, pea, common bean, faba bean, lima bean, cowpea, papaya, red currant, apple, apricot, pear, peach, plum, cherry, walnut, almond, grapevine, blackberry, citrus, fig, sugarcane, groundnut, canola, watermelon, beetroot, various grasses, bent grass, safed musli (Chlorophytum borivillianum – medicinal plant), rose, candytuft, chrysanthemum, iris, lily, pine, oak, peppermint, spearmint (CABI, 2016; Castillo & Vovlas, 2007; Siddiqui et al., 1973; Smiley et al., 2014).

Symptoms: In general, root lesion infection results in plant exhibiting symptoms of chlorosis, wilting, and stunting. Infected roots show initial symptoms of small, water-soaked lesions that soon turn brown to black. Lesions are formed along the root axis and may coalesce laterally to girdle the roots which are killed. Affected root tissue may slough off leaving a severely reduced root system. Secondary infection by fungi and bacteria may further destroy the root system by causing sloughing off of the root tissues and rot. Plant yield is reduced and in severe infections plants may be killed.

Damage Potential: Pratylenchus thornei is capable to reducing root growth and function thereby, causing reduction in plant growth and yield of its associated host plants.

Spread: On its own, Pratylenchus species move can move 1-2 m from an infected root. The main mode of long and short distance spread is artificial. Infected roots, bare root propagative plant materials, soil debris, run-off and irrigation water, cultivation tools, equipment and human activity that can move soils from infested to non-infested sites.

Worldwide Distribution: Pratylenchus thornei has been reported worldwide in Asia: Afghanistan, Azerbaijan, India, Iran, Israel, Japan, Jordan, Republic of Korea, Pakistan, Saudi Arabia, Syria, Tajikistan, Turkey; Africa: Algeria, Egypt, Kenya, Libya, Malawi, Morocco, Nigeria, South Africa, Sudan, Tunisia; Europe: Belgium, Bulgaria, Croatia, Cyprus, Denmark, France, Germany, Italy, Netherland, Poland, Portugal, Romania, Russian Federation, Slovakia, Slovenia, Spain, United Kingdom, Yugoslavia; North America: USA, Canada, Mexico; South America: Argentina, Chile, Venezuela; Oceania: Australia: New South Wales, Queensland, South Australia, Tasmania, Victoria, Western Australia (CABI, 2014; Castillo & Vovlas, 2007; Fortuner, 1977).

In the USA, Pratylenchus thornei has been reported in California, and several other states including, Colorado, Idaho, Maryland, Nebraska, Ohio, Oregon, Utah, Virginia, and Washington (CABI, 2014; Castillo & Vovlas, 2007; Fortuner, 1977).

Official Control: Currently, Pratylenchus thornei is rated ‘D’ by CDFA. The following countries include the species on their Harmful Organism Lists: Brazil, Canada, Costa Rica, Honduras, Indonesia, Jordan, Panama, and Peru (USDA-PCIT, 2016).

California Distribution: Pratylenchus thornei is widely distributed in California.

California Interceptions: Pratylenchus thornei has been detected in several incoming shipments of plants and soil to California.

The risk Pratylenchus thornei would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

Risk is High (3) – Pratylenchus thornei is able to establish throughout the State.

2) Known Pest Host Range: Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

Risk is Medium (2) – Pratylenchus thornei is an important parasite of wheat and other cereals, but its diverse range of hosts are grown throughout the State and include, fruit trees, vegetable crops, and ornamentals.

3) Pest Dispersal Potential: Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

Risk is High (3) –Long and short distance spread is mainly infected roots, bare root propagative plant materials, soil debris, run-off and irrigation water, cultivation tools, equipment and human activity that can move soils from infested to non-infested sites.

4) Economic Impact: Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

Risk is Low (1) – At the local residential/grower level, Pratylenchus thornei infections could result in lowered crop yield.

5) Environmental Impact: Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

Risk is Medium (2) – The impact of Pratylenchus thornei on natural environments is most likely not significant as the species is already widespread without causing apparent detriment to ecological balances and processes, however, the infestations of this root lesion nematode could affect home/urban gardening.

Consequences of Introduction to California for Pratylenchus thornei:

Add up the total score and include it here. (Score)

-Low = 5-8 points

–Medium = 9-12 points

-High = 13-15 points

Total points obtained on evaluation of consequences of introduction of Pratylenchus thornei to California = (11).

-Not established (0) Pest never detected in California, or known only from incursions.

-Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

-Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Evaluation is High (-3). Pratylenchus thornei is widely spread in several contiguous and non-contiguous climate and host regions throughout the state.

Final Score:

7) The final score is the consequences of introduction score minus the post entry distribution and survey information score: (Score)

Final Score: Score of Consequences of Introduction – Score of Post Entry Distribution and Survey Information = 8

Uncertainty:

None.

Conclusion and Rating Justification:

Based on the evidence provided above the proposed rating for the lesion nematode, Pratylenchus thornei, is C.

References:

CABI. 2014. Pratylenchus thornei (nematode, California meadow) basic datasheet. http://www.cabi.org/cpc/datasheet/43903.

Castillo, P., R. M. Jiménez Díaz, A. Gomez-Barcina, and N. Vovlas. 1995. Parasitism of the root-lesion nematode Pratylenchus thornei on chickpea. Plant Pathology 44:728-733.

Fortuner, R. 1977. Pratylenchus thornei. Commonwealth Institute of Helminthology (C.I.H.) descriptions of plant-parasitic nematodes set 7, No. 93.

USDA-PCIT. 2016. United States Department of Agriculture, Phytosanitary Certificate Issuance & Tracking System (PCIT). https://pcit.aphis.usda.gov/PExD/faces/ViewPExD.jsp .

Sher, S. A. and M. W. Allen. 1953. Revision of the genus Pratylenchus (Nematoda: Tylenchidae). University of California Publications in Zoology 57:441-447.

Siyanand, A. R. Seshadri, and D. R. Dasgupta. 1982. Investigation on the life cycles of Tylenchorhynchus vulgaris, Pratylenchus thornei and Hoplolaimus indicus individually and in combined infestations in corn. Indian Journal of Nematology 12:272-276.

Siddiqui, I. A., S. A. Sher and A. M. French. 1973. Distribution of plant parasitic nematodes in California. State of California Department of Food and Agriculture, Division of Plant Industry. 324p.

Smiley, R.W., G. Yan, J. A. Gourlie. 2014. Selected Pacific Northwest rangeland and weed plants as hosts of Pratylenchus neglectus and P. thornei. Plant Disease 98: 1333-1340.

Responsible Party:

John J. Chitambar, Primary Plant Pathologist/Nematologist, California Department of Food and Agriculture, 3294 Meadowview Road, Sacramento, CA 95832. Phone: 916-262-1110, plant.health[@]cdfa.ca.gov.

Comment Period: CLOSED

The 45-day comment period opened on Jun 2, 2016 and closed on Jul 17, 2016.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: C

Posted by ls

Nematodes

Tylenchorhynchus spp. Cobb, 1913

June 2, 2016 2difficult

California Pest Rating for

Tylenchorhynchus spp. Cobb, 1913

Pest Rating: C

PEST RATING PROFILE

Initiating Event:

During the 1950-60s, several species of plant parasitic nematodes were given a ‘D’ rating as they were regarded as parasites, predators or organisms of little or no economic importance that did not require State enforced regulatory action. However, these nematode species were inaccurately assigned a D rating as most, if not all, are plant parasitic and therefore, capable of damaging plant production and causing significant economic losses especially at the county and local residential/grower level. Furthermore, the detection of plant parasitic nematodes in nursery stock may be an indication of contamination in violation of the State’s standard of pest cleanliness required for nurseries. Tylenchorhynchus spp. were originally rated D. The risk of infestation and permanent rating of this genus group are re-assessed here.

History & Status:

Background: Generally, pest risk assessments and assignment of pest ratings are conducted per individual pest species and not per genus group primarily due to differing pest biologies, geographical distributions, host ranges, damage potentials, and risk mitigating requirements. However, an exception to this rule is made here for the genus Tylenchorhynchus largely because of historical practice. Over the past several decades, the genus, Tylenchorhynchus, was seldom differentiated to species level by CDFA Nematologists mainly due to i) the common occurrence and wide distribution of member species within California, ii) no state enforced regulatory action required subsequent to their detection, and iii) greater demands of time involved in diagnosing high risk and other nematode species considered to be of greater economic importance than those belonging to Tylenchorhynchus.

Members of the genus, Tylenchorhynchus, are sometimes known as ‘stunt nematodes’. Species reproduce mainly by amphimixis (fertilization by female and male) producing eggs, three juvenile stages, and adults. These nematodes usually inhabit the soil-root region of plants and feed as obligate migratory ectoparasites of roots using a stylet (sword-like hollow tooth) to feed on epidermal cells. All motile juvenile and adult stages feed. (Mai et al., 1996; Maggenti, 1981).

Hosts: Tylenchorhynchus spp. are associated with the roots of a wide range of plants including tobacco, cotton, oats, and corn as well as other agricultural crops, fruit trees, ornamentals, nursery stock, forest trees and shrubs, desert shrubs, grasses, and weeds. The host status of associated plants is not always known.

Symptoms: General plant damage associated with Tylenchorhynchus spp. includes stunting of the root system which is expressed aboveground by yellowing of foliage, stunted top growth, and sometimes wilt and defoliation (Maggenti, 1981).

Damage Potential: Generally, Tylenchorhynchus spp. are considered mild pathogens of plants and are common associates of several plants (Norton, 1984). However, plant damage caused by high populations of stunt nematodes may be more significant in small-area plant productions and/or containerized crops in nursery, residential and local situations than in large acreages and environments such as, pastures, parks, and cultivated fields. Crop losses under field conditions are not reported, however, under experimental conditions, reductions in root and plant growth have been demonstrated by certain species, e.g., T. annulatus on sugarcane and Bermuda grass; T. dubius on beans (Bridge, 1974; Siddiqi, 1976). Tylenchorhynchus claytoni causes economic damage on tobacco (Mai et al., 1996). Crop damage under field conditions may be difficult to assess as Tylenchorhynchus spp. are often mixed with other genera and/or two or more stunt nematode species occurring together.

Spread: The main mode of long and short distance spread through artificial means: movement of nematode-contaminated soil, run-off and irrigation water, cultivation tools, equipment and any human activity that can move soils from infested to non-infested sites.

Worldwide Distribution: Tylenchorhynchus spp. are distributed worldwide.

Official Control: Currently, Tylenchorhynchus spp. are D rated pests in California (see ‘Initiating Event’). Tylenchorhynchus spp. are on the ‘Harmful Organism Lists” for Australia and the Republic of Nauru (USDA-PCIT, 2016).

California Distribution: Tylenchorhynchus spp. are distributed throughout California.

California Interceptions: For the past several decades, Tylenchorhynchus spp. have been detected in several imported plant and soil shipments intercepted in California.

The risk Tylenchorhynchus spp. would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

Risk is High (3) –Tylenchorhynchus spp. are able to establish throughout the State.

2) Known Pest Host Range: Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

Risk is High (3) –Tylenchorhynchus spp. are known to be associated with several diverse plant species, however, the host status of associated plants is not always known.

3) Pest Dispersal Potential: Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

Risk is High (3) – The main mode of long and short distance spread through artificial means: movement of contaminated soil, run-off and irrigation water, cultivation tools, equipment and any human activity that can move soils from infested to non-infested sites. Increase in reproduction rates depends on the plant species parasitized.

4) Economic Impact: Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

Risk is Low (1) –Generally, Tylenchorhynchus spp. are considered mild pathogens of plants. However, under high population levels in residential, nurseries and other small-area plantings, Tylenchorhynchus spp. infections could result in lowered crop yield.

5) Environmental Impact: Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

Risk is Medium (2) – The impact of Tylenchorhynchus spp. on natural environments is most likely not significant as the species is already widespread without causing apparent detriment to ecological balances and processes, however, heavy infestations of spiral nematodes could affect home/urban gardening.

**Consequences of Introduction to California for Tylenchorhynchus spp.:**

Add up the total score and include it here. (Score)

-Low = 5-8 points

–Medium = 9-12 points

-High = 13-15 points

Total points obtained on evaluation of consequences of introduction of Tylenchorhynchus spp. to California = (12).

-Not established (0) Pest never detected in California, or known only from incursions.

-Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

-Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Evaluation is High (-3). Tylenchorhynchus spp. are widely spread in several contiguous and non-contiguous climate and host regions throughout the state.

Final Score:

7) The final score is the consequences of introduction score minus the post entry distribution and survey information score: (Score)

Final Score: Score of Consequences of Introduction – Score of Post Entry Distribution and Survey Information = 9

Uncertainty:

None.

Conclusion and Rating Justification:

Based on the evidence provided above the proposed rating for the spiral nematodes, Tylenchorhynchus spp., is C.

References:

Bridge, J. 1974. Tylenchorhynchus dubius. Commonwealth Institute of Helminthology (C. I. H.) descriptions of plant-parasitic nematodes. Set 4, No. 51.

Mai, W. F., P. G. Mullin, H. H. Lyon, and K. Loeffler. 1996. Plant parasitic nematodes – a pictorial key to genera. Fifth Edition. Comstock Publishing Associates a division of Cornell University Press, Ithaca and London. 277 p.

Maggenti, A. 1981. General nematology. Springer-Verlag New York Heidelberg Berlin. 372 p.

Norton, D. C. 1984. Nematode parasites of corn. In Plant and Insect Nematodes, edited by W. R. Nickle. Marcel Dekker, Inc. New York and Basel. 61-94 pp.

Siddiqi, M. R. 1976. Tylenchorhynchus annulatus. Commonwealth Institute of Helminthology (C. I. H.) descriptions of plant-parasitic nematodes. Set 6, No. 85.

USDA-PCIT. 2016. United States Department of Agriculture, Phytosanitary Certificate Issuance & Tracking System (PCIT). https://pcit.aphis.usda.gov/PExD/faces/ViewPExD.jsp .

Responsible Party:

John J. Chitambar, Primary Plant Pathologist/Nematologist, California Department of Food and Agriculture, 3294 Meadowview Road, Sacramento, CA 95832. Phone: 916-262-1110, plant.health[@]cdfa.ca.gov.

Comment Period: CLOSED

The 45-day comment period opened on Jun 2, 2016 and closed on Jul 17, 2016.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: C

Posted by ls

The CDFA's Plant Health and Pest Prevention Services Division grants the public opportunities to comment on proposed pest ratings. The following type of proposals are available for comment:

California Pest Rating for

Pratylenchus coffeae (Zimmermann) Filipjev & Schuurmans-Stekhoven

Pest Rating: B

PEST RATING PROFILE

Initiating Event:

History & Status:

Consequences of Introduction to California for Pratylenchus coffeae:

Final Score:

Uncertainty:

Conclusion and Rating Justification:

References:

Responsible Party:

Comment Period: CLOSED

Comment Format:

Pest Rating: B

California Pest Rating for

Aonidiella orientalis (Newstead): Oriental Scale

Hemiptera: Diaspididae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

History & Status:

Consequences of Introduction:

Consequences of Introduction to California for Aonidiella orientalis (Oriental Scale): High (15)

Final Score

Uncertainty:

Conclusion and Rating Justification:

References:

Responsible Party:

Comment Format:

Pest Rating: A

California Pest Rating for

Clavaspis herculeana (Common Name): Herculeana Scale

Hemiptera: Diaspididae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

History & Status:

Consequences of Introduction:

Consequences of Introduction to California for Clavaspis herculeana (Herculeana scale): High (14)

Final Score

Uncertainty:

Conclusion and Rating Justification:

References:

Responsible Party:

Comment Format:

Pest Rating: A

California Pest Rating for

Halticus bractatus (Say): Garden Fleahopper

Hemiptera: Miridae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

History & Status:

Consequences of Introduction:

Consequences of Introduction to California for Halticus bractatus (Garden Leafhopper): High (13)

Final Score

Uncertainty:

Conclusion and Rating Justification:

References:

Responsible Party:

Comment Format:

Pest Rating: A

California Pest Rating for

Ceroplastes stellifer (Westwood): Stellate Scale

(synonym Vinsonia stellifera)

Hemiptera: Coccidae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

History & Status:

Consequences of Introduction:

Consequences of Introduction to California for Ceroplastes stellifer (Stellate Scale): High (13)

Final Score

Uncertainty:

Conclusion and Rating Justification:

References:

Responsible Party:

Comment Format:

Pest Rating: A

**Consequences of Introduction to California for Pratylenchus coffeae:**

**Consequences of Introduction to California for Aonidiella orientalis (Oriental Scale): High (15)**

**Consequences of Introduction to California for Clavaspis herculeana (Herculeana scale): High (14)**

**Consequences of Introduction to California for Halticus bractatus (Garden Leafhopper): High (13)**

**Consequences of Introduction to California for Ceroplastes stellifer (Stellate Scale): High (13**)

**Consequences of Introduction to California for Dysmicoccus texensis: High (13)**

**Consequences of Introduction to California for Aleurodicus dispersus (Spiraling Whitefly): High(14)**