First report of Phytophthora citricola on Mangifera indica in Spain

Abstract

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 µ m) 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.

<I>Phytophthora multivora</I> sp. nov., a new species recovered from declining <I>Eucalyptus</I>, <I>Banksia</I>, <I>Agonis</I> and other plant species in Western Australia

“…In GenBank, 11 ITS sequences, designated as P. citricola , are identical to P. multivora . Seven are from unpublished studies in Hungary, Canada, Switzerland, Korea and Japan, and two sequences are from isolates of Moralejo et al (2008) from ornamental nurseries in Spain, an isolate from Mangifera indica in Spain ( Zea-Bonilla et al 2007 ). In addition, an isolate designated as P. sojae in a study from Japan also has identical sequence ( Villa et al 2006 ).…”

Global invasion history of the emerging plant pathogen Phytophthora multivora

“…The species has since been reported on five continents, usually associated with diseases of woody plants. Reports from natural ecosystems [ 12 , 25 , 26 ], production orchards [ 27 – 30 ] and restoration sites [ 31 , 32 ] are from Mediterranean climates, whereas reports from ornamentals and the nursery trade extend into temperate regions of Europe [ 19 ], North America [ 33 ] and Japan [ 34 , 35 ]. The global distribution of P. multivora brings into doubt the assumption that it is native to Western Australia.…”