Tinatin Elbakidze
Laboratory of the Ministry of Agriculture, Georgia
Title: A survey for grapevine leafroll-associated virus-1 and -3 in Georgian vineyards
Biography
Biography: Tinatin Elbakidze
Abstract
Grapevine leafroll associated virus 1 (GLRaV-1) and -3 (GLRaV-3) are the most widespread and dangerous causal viral agents of severe grapevine viral disease - Grapevine leafroll disease (GLD). Georgian vineyards according to its importance as a wine-producing region is focused on increasing the quality of wines produced from indigenous grape varieties (whiteberried cultivar-Rkatsiteli and red-berried cultivar-Saperavi), making them in a clean international style. Main objectives of this study were to define which member of GLD is presented predominantly in Georgian vineyards also Application of serological approaches for the surveillance of serological types of GLRaV-s for a better diagnostic tool for the analysis of large number of samples. Survey for the detection of GLRaV-1 and GLRaV-3 viruses was conducted from widely distributed grapevine cultivars (Rkatsiteli and Saperavi) growing in vineyards located in traditional wine-producing region Kakheti, the east part of Georgia. A total of 600 samples (300- Rkatsiteli and 300 Saperavi) were collected and analyzed (Das Elisa kits, Bioreba, Switzerland) from ten vineyards during 2016 and 2017 growing seasons. The study determined the incidence of both virus serotypes (34.2%) as either single or mixed infections. Virus profiles were determined for individual vines. Analysis showed that GLRaV-3 virus was predominantly distributed in Saperavi cultivar (20.7%) while in case of Rkatsiteli both viruses were presented (GLRaV-1-18%, GLRaV-3- 17.7%) equally. The overall analysis showed that GLRaV-3 virus was the prevalent and contributed 19.2% of total samples while GLRaV-1 virus was presented in 15% cases respectively. Mixed infections were found in 3% of samples. Annually testing of vines used for further propagation in nurseries might be recommended in order to be sure in quality of new plant material. Diagnostic procedures should be comprehensive to define whether infected vine is removed from the vineyard or virus free rootstocks are used for establishing new vineyards.