Potato is the world's fourth widespread food crop, following maize, wheat, and rice. Tubers play an important role in the spread of virus diseases in different seed production regions in Bulgaria. The most important viruses in potatoes in Bulgaria include Potato virus Y (PVY), Potato leaf roll virus (PLRV), Potato virus X (PVX), Potato virus S (PVS), Potato virus M (PVM), and the Tobacco rattle virus (TRV). Most of the viruses in potatoes have no symptoms on the tubers and the fact plays an important role for their easy dissemination by the growers. In that way, after planting the tubers, the quality and yield of the production are severely reduced. The use of virus-free tubers by growers is very important for the disease control and reduction of the production loss.
Distribution and economic impact of plant viruses in potatoes for seed production in Kyustendil region