Isolated finding of Xylophilus ampelinus in Slovenia
In Slovenia, the presence of Xylophilus ampelinus (EPPO A2 list) was suspected on the basis of visual observation of symptoms in the 1960s. The disease was only observed in a limited coastal area, but some very sensitive local cultivars (e.g. cvs ‘Rebula’ and ‘Pinela’) were temporarily abandoned in this infected area. However, one vineyard of cv. ‘Rebula’ remained till today. Since 2002, symptoms of bacterial blight have been observed again in this vineyard. Samples were collected and tested by several methods (biochemical tests, fatty acid profiling, IF, nested-PCR, pathogenicity tests) and isolation of the bacterium on agar media was attempted. Results of laboratory tests confirmed the presence of X. ampelinus in this vineyard in Slovenia. In 2002, disease symptoms (angular lesions on leaves) were conspicuous and X. ampelinus was identified. In 2003 and 2004, symptom expression was faint. In 2003, no positive sample could be found, but X. ampelinus was again isolated and identified (colony morphology and RT-PCR) in 2004. It is concluded that symptoms observed in the 1960s were probably caused by X. ampelinus, and that at present the pathogen is still confined to this single vineyard as no symptoms have been observed in surrounding vineyards. This failure to spread is most probably related to the absence of vectors.
The situation of Xylophilus ampelinus in Slovenia can be described as follows: Present, first observed in the 1960s and confirmed in 2005 in a very limited area (1 vineyard).
Sources
Dreo T, Seljak G, Janse JD, van der Beld I, Tjou-Tam-Sin L, Gorkink-Smits P, Ravnikar M (2005) First laboratory confirmation of Xylophilus ampelinus in Slovenia. Bulletin OEPP/EPPO Bulletin 35(1), 149-155.