Viruses of grapevine in Kosovo

Abstract

Surveys for virus and virus-like diseases were carried out in commercial vineyards in the provinces of Rahovec and Suhareka of Kosovo. Samples were collected at random from 306 individual vines for laboratory testing. Leafroll and rugose wood symptoms were commonly observed in the field, whereas fanleaf symptoms were very rare. A total of 68% of ELISA-tested vines (208 out of 306) was infected by one (40.9%) or multiple (27.1%) viruses. The highest infection rate was found in Suhareka province (75%). Grapevine fleck virus (GFkV) was the most widespread (52.0%), followed by Grapevine leafroll-associated virus 3 (GLRaV-3, 18.3%), Grapevine leafroll-associated virus 1 (GLRaV-1, 15.7%), and Grapevine virus A (GVA, 11.1%). Other economically relevant viruses occurred rarely, i.e. Grapevine fanleaf virus (GFLV, 1.6%), Grapevine virus B (GVB, 1.0%) and Grapevine leafroll-associated virus 2 (GLRaV-2, 0.3%). Arabis mosaic virus (ArMV) was not found. Some of the most important grapevine varieties cultivated in Kosovo, i.e. Smederevka, Vranac, Prokupac, Italian Muskat, Muskat of Hamburg, and Italian Riesling, had average infection rates that ranged from 63% to 85%. In RT-PCR, Grapevine rupestris stem pitting associated virus (GRSPaV) was detected in 80.4% of the vines. Vein mosaic and vein necrosis symptoms were detected in graft-inoculated V. riparia and 110R indicators. At least one virus-tested candidate clone of 19 different grapevine varieties were identified, that could represent a potential primary source for a grapevine certification program in Kosovo.