Pepper vein mottling virus (PVMV) – a new virus for tobacco in Bulgaria

The aim of the present study is to trace the emergence and development of TEV and PVMV, new viruses for tobacco in Bulgaria, in the three varietal groups of Burley, Virginia and Basmi tobacco grown in the central part of southern Bulgaria. During the period 2017-2019, immunological studies were carried out to prove new viruses for tobacco in Bulgaria from the group of potyviruses PVMV and TEV. A kit for serological identification of the French company SEDIAG S.A.S. was used to prove the viruses. To detect TEV, TAS-ELISA was performed with IgG dilution of 1:100 and DAS-ELISA - to detect PVMV with IgG dilution of 1:100. In Virginia and Basmi tobacco variety groups, the potyvirus PVMV was serologically proven, and the virus was identified for the first time in tobacco in Bulgaria. PVMV was demonstrated in monoinfection and in complex with TEV in isolates from the cultivar group Virginia and Basmi. TEV and PVMV were not detected in isolates from the Burley cultivar group. In tobacco, the two potyviruses cannot be distinguished based on symptoms alone. Accurate diagnosis is possible by applying an ELISA or PCR test