NEW DISEASE REPORT Blackwell Publishing Ltd Plant Pathology (2007) 56, 356 Doi: 10.1111/j.1365-3059.2007.01523.x First report of sugar beet crown wart disease caused by Urophlyctis leproides in Egypt M. I. Goudaa and A. A. Emeranb* a Plant Pathology Research, Institute Agriculture Research Center, Giza; and bPlant Pathology Branch, Department of Agricultural Botany, Faculty of Agriculture, University of Kafr El-Sheikh, 33516-Kafr El-Sheikh, Egypt Leaf and crown wart, marbled or beet root tumour are some of the common names given to a disease of sugar beet (Beta vulgaris) caused by Urophlyctis leproides (formerly Physoderma leproides). It was first reported in Algeria in 1894 (Trabut, 1894). Since then, the disease has been recorded in Argentina, Italy, Spain, United Kingdom, Palestine and the USA (Whitney, 1971). In Egypt, the disease was observed during harvest (2003, 2004, 2005) at three locations in the Nile Delta (Behira, Gharbia and Kafr El-Sheikh) on a range of sugar beet cultivars (Gloria, Kawmera, Oscar poly, Othus poly and Pleno). Disease incidence (DI) was less than 1% in 2003, 1–2% in 2004 and 3% in 2005. Although the DI is currently low, if the trend observed over the last few years continues, the disease could reach epidemic levels in the near future. The disease exhibited typical symptoms on root crowns and occasionally on petioles and leaf blades. Galls on leaf blades and petioles are greenish brown and have a rough appearance. Affected leaves are malformed. On the crown, galls range in size from 1 cm to (most commonly) 8–10 cm. These galls are spherical, rough and are attached to the host by a narrow base. Gall colour was variable, ranging from shades of green through yellow to brown depending on the age of plant cultivar. Galls occurred singly or coalesced to form complexes. Sections made through a crown gall revealed cavities filled with thick-walled sporangia (resting spores) surrounded by thickened wall. Sporangia were light brown, spherical to ovoid or concave (25 ± 5 × 40 ± 5 µm) in diameter (Ruppel, 1995). As the gall decomposes, resting sporangia are released into the soil. Soil surveys were carried out in the affected areas and detected resting sporangia. Twenty seedlings of B. vulgaris cv. Gloria were inoculated with 105 resting spores mL−1 and incubated 22 ± 2°C in continuous fluorescent light for 48 h, followed by 14 h light and 10 h dark. Uninoculated plants were used as a control. Symptoms appeared on the test plants after 11 days and sporangia were reisolated from the mature gall tissues (Mahmoody et al., 1997). No symptoms were observed on uninoculated controls. This is the first report of sugar beet crown wart disease (U. leproides) affecting B. vulgaris in Egypt. Acknowledgements The authors would like to thank Dr El-Sayed Belal for his valuable opinion and Mr Fath for his technical assistance. References Mahmoody B, Munassian V, Kashani A, 1997. Occurrence of leaf and crown wart disease, caused by Urophlyctis leproides, its importance and effects on sugar beet yield quality in Khuzestan. Iranian Journal Plant Pathology 33, 22–3. Ruppel EG, 1995. Beet tumor of crown wart. In: Withney ED, Duffus JE, eds. Compendium of Beet Diseases and Insects. St. Paul, MN, USA: APS Press, 16–17. Trabut L, 1894. Sur une Ustilaginée parasite de la Betterave (Entyloma leproideum). Comptes Rendus Des Séances De L’Académie Des Sciences Paris 118, 1288–9. Whitney ED, 1971. The first confirmable occurrence of Urophlyctis leproides on sugar beet in North America. Plant Disease Reporter 55, 30–2. *E-mail: emeranaa@yahoo.com. Accepted 22 June 2006 at www.bspp.org.uk/ndr where figures relating to this paper can be viewed. Plant Pathology (2007) 56, 356 Doi: 10.1111/j.1365-3059.2007.01535.x First report of Phytophthora citricola on Mangifera indica in Spain T. Zea-Bonillaa, P. M. Martín-Sáncheza, J. M. Hermosob, M. P. Carmonac, E. Segundoc and R. M. Pérez-Jimenéza* a Instituto Andaluz de Investigación y Formación Agraria, Pesquera, Alimentaria y de la Producción Ecológica (IFAPA-CICE). CIFA Churriana. Cortijo de la cruz s/n, Churriana, 29140, Málaga; bEstación Experimental La Mayora (CSIC), 29750, Algarrobo-Costa, Málaga; and cIFAPA-CICE. CIFA La Mojonera, Autovía del Mediterraneo km 420, 04745 La Mojonera, Almería, Spain In the last three years, mango trees (Mangifera indica) located in a fifteenyear-old orchard in the sub-tropical fruit-producing area of Andalucia (southern Spain) have developed symptoms such as wilting, chlorosis, sparse leaf production, microphylly and bark cracking. In July 2004, a Phytophthora species was isolated at low frequency from surfacedisinfected necrotic roots using a Phytophthora-selective medium (Tsao & Ocana, 1969). Colonies on potato dextrose agar had dense white aerial hyphae with a stellate pattern. On V8 juice agar (V8A) they had sparse aerial hyphae with a radiate pattern. Sporangia obtained in axenic cultures (Chen & Zentmyer, 1970) were semi-papillate, obovoid and 51 (28–52) × 36 (22–37) µm. Paragynous antheridia, spherical oogonia and oospores of 28 (19–32) µm diameter, were homothallically produced on V8A. Ribosomal DNA (regions ITS1, 5·8S rDNA and ITS2) was amplified and sequenced (GenBank Accession No. AM235209) and compared with sequences of known Phytophthora species obtained from GenBank. The closest matches (99% identity) were with P. citricola which was supported by morphological characteristics. A pathogenicity test was conducted using 10 two-year-old mango plants (cv. Florida) growing in pots containing 15 L soil inoculated with sterile wheat seeds colonised by P. citricola (isolate CH455; Spanish Type Culture Collection, CECT 20567) from mango roots (25 g/L substrate). Ten non-inoculated plants were used as controls. No aerial symptoms were observed but 4 months after inoculation, P. citricola was recovered from necrotic roots of inoculated plants confirming its pathogenicity to mango. In addition, detached mango leaves and stems of mango seedlings (cv. Gomera 3) were inoculated with mycelial plugs of isolate CH 455. Lesions developed on leaves and seedlings and the pathogen was re-isolated. Phytophthora citricola causes root rot and trunk canker on many economically important plants, with reports of the disease on different hosts throughout Europe (Sawada, 1996), but this is the first report of P. citricola occurring on mango trees and the first time this pathogen has been reported in Spain. The presence of P. citricola in this sub-tropical area represents a risk, not only to mango, but also to avocado (Persea americana), which is another susceptible host (Coffey et al., 1988). References Chen D, Zentmyer GA, 1970. Production of sporangia by Phytophthora cinnamomi in axenic culture. Mycologia 62, 397– 402. Coffey M, Oudemans P, Ouimette D, 1988. Phytophthora citricola: another cause of avocado decline. California Avocado Society Yearbook 72, 127–31. Sawada K, 1996. Phytophthora citricola. In: Erwin DC, Ribeiro OK, Phytophthora Diseases Worldwide. St Paul, MN, USA: APS Press, 282–7. Tsao PH, Ocana G, 1969. Selective isolation of species of Phytophthora from natural soils on improved antibiotic medium. Nature 223, 636 – 8. *E-mail: patologia@olinet.es. Accepted 31 August 2006 at www.bspp.org.uk/ndr where figures relating to this paper can be viewed. 356 © 2007 The Authors Journal compilation © 2007 BSPP