First report of European stone fruit yellows phytoplasma in Slovenia
The NPPO of Slovenia has recently informed the EPPO Secretariat of the situation of European stone fruit yellows phytoplasma (EU Annex I/A2, as Apricot chlorotic leafroll phytoplasma) in Slovenia. In 1999, severe symptoms of leptonecrosis were observed in peach and apricot trees in the submediterranean region in the western part of Slovenia (Nova Gorica). In 2000, a European stone fruit yellows caused by phytoplasmas belonging to apple proliferation group (16SrX) was confirmed by laboratory testing using polymerase chain reaction (PCR), nested PCR and restriction fragment length polymorphism (RFLP) analyses. These sensitive and specific molecular methods were introduced for the routine detection of European stone fruit yellows at the official testing laboratory.
At the same time, the presence of a vector, Cacopsylla pruni, was observed in the ESFY-infected areas. This vector was tested in the laboratory and found positive for European stone fruit yellows. Recently, a progression of European stone fruit yellows in Slovenia was reported, based on visual assessments of symptoms. The disease can spread by infested Cacopsylla pruni and infected plants for planting, especially where sensitive cultivars of stone fruit are grown. The presence of European stone fruit yellows phytoplasma was confirmed by laboratory testing of apricot, peach and plum trees from different regions in Slovenia (Primorska, Kras, Maribor). European stone fruit yellows is listed as Apricot chlorotic leafroll phytoplasma on the A2 quarantine list, and infected areas are subject to official control. A systematic delimiting survey is planned in 2003. Visual inspections of stone fruit growing areas will be combined with laboratory testing and followed by the destruction of infected trees, spraying of vectors and avoiding of planting of sensitive stone fruit cultivars. Control of nursery stock material and imported material by visual inspection and laboratory testing is part of official control. The situation of European stone fruit yellows phytoplasma in Slovenia can be described as follows: Present: confirmed in some parts of Slovenia where host crops are grown.
Sources
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NPPO of Slovenia, 2002-09
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