The study of viral diseases in georgian vine grafted nurseries

Grapevine infections are one of the most viral diseases affecting grapevines throughout the world. The impact on vine health, crop yield and quality is difficult to assess due to a high number of variables, but significant economic losses are consistently reported over the lifespan of a vineyard if intervention strategies are not implemented. Georgia is one of the oldest wine producing regions. The main goal of the research was to study the spreading of grapevine viral diseases for further selection of virus-free material in Georgia. Survey for the detection of viral agents was conducted from grapevine varieties: Rkatsiteli, Rkatsiteli Pink and Qisi located in vineyards grafted nurseries in the east part of Georgia region of Mtskheta in Jighaura and Mukhrani. Grapevine cultivars were tested for 6 types of viruses: Grapevine Fanleaf Virus(GFLV), Grapevine Fleck Virus (GFkV), Grapevine  Leaf Roll Virus-1 (GLRaV-1), Grapevine  Leaf Roll Virus-2 (GLRaV-2),  Grapevine  Leaf Roll Virus-3 (GLRaV-3) and Grapevine Virus A (GVA) by means of Triple and Double Antibody Sandwich-Enzyme linked Immunosorbent Assay (DAS-ELISA, TAS –ELISA) using monoclonal and polyclonal antibodies. The results showed that different types of viral infections were accumulated in 36.09% of tested samples.  Among viral pathogens tested GLRV-2 (0.50%), GLRaV-3 (1.21%) and GVA (3.66%) were in minority. GLRaV-1, GFLV and GFkV virus presence, respectively: 8.04%, 12.68% and 19.26% in collected samples was relatively high comparing to others. It should be noted that in the same samples were found mixed infections (2 or 3 types of viruses), particularly 9.8% of patterns were containing GFLV and GFkV viruses. Regular sampling and testing of all vines has provided virus free propagation material in Jighaura and Mukhrani grafted nurseries in Georgia.