Occurrence and Molecular Characterization of Some Important Potato Viruses in Tokat, Turkey

Abstract Background Potato production is affected by various abiotic and biotic factors such as viruses, fungi, and bacteria. Viruses are considered the main limiting factor in potato production areas.Methods and Results Leaf samples were collected from potato plants showing signs of viral diseases in five districts of Tokat province in Turkey. To detect the presence of potato viruses, 418 leaf samples were subjected to an RT-PCR test using virus-specific primers. One or more viruses were detected in 220 (52.63%) leaf samples tested. PVY was the most prevalent (47.12%), followed by PVS (16.74%), PVX (5.98%), and PLRV (5.26%). The PVX and PLRV infections were found to be few. The most common multiple infections were PVY+PVS with 6.9% rates. Phylogenetic analysis based on sequence analysis of some positive isolates revealed that all Turkish PVS isolates were grouped with the PVSO cluster. Two PVY isolates were clustered with Group PVYN-WI, and one isolates clustered with PVYNNTN isolates in the phylogenetic tree. Regarding nucleotide sequence similarity of the CP region, PVX isolates were divided into two major groups (Group I and Group II). Turkish PVX isolates were grouped within Group I that including isolates referred to as type X. According to phylogenetic analysis of PLRV isolates, Turkish isolates were clustered into two major groups. Six PLRV isolates belong to Group 1 and one isolate was clustered Group 2. Conclusion The results indicate that these viruses were detected at different rates in potato fields. This is the first report about the molecular characterization of PVX and PVS based on CP sequences in Turkey. These reports will provide a base for further research on the phylogenetic features of the above-mentioned viruses, including the effect.