The distribution and genetic variability of potato viruses in Russian regions

Viral diseases represent an increasingly serious threat for potato production all around the world, including in the Russian Federation, which leads to a significant decrease in potato crop yield, quality, and shelf life. In this study, we carried out screening of potato leaf and tuber samples collected from commercial potato fields to determine the spread of potato viruses in 16 regions of the European part, and two regions in the Ural Federal District, of the Russian Federation. The samples were sequenced, and full-length viral genomes were subsequently assembled de novo. A phylogenetic analysis of the identified virus variants was performed to assess their genetic diversity and possible origin. It has been shown that the most dangerous and economically important potato virus Y (PVY) is widespread and is represented by recombinant variants, NTNa, NTNb, and N-Wi being the most common ones. The second most common virus was potato virus M (PVM), which was frequently encountered in conjunction with potato virus S (PVS). The presence of potato leafroll virus (PLRV), which is recognized as an economically detrimental potato pathogen, along with PVY, has been found in two Russian regions. Mixed infections were detected in at least half of the studied samples, many containing both PVY and PVM (about one-third of all the samples). The data on the evolutionary variability of virus populations lay the groundwork for developing innovative strategies meant to contain a broad range of viruses and their strains using specifically designed double-stranded RNA (dsRNA).