First report of Clavibacter michiganensis subsp. michiganensis infecting potato in Russia.
Yellow-pigmented clavibacteria were isolated from diseased potato plants and tubers from 5 regions of Russia, between 2011 and 2017. Severe outbreaks of the disease were recorded in the central and northwest parts of the Russian Federation. Plants exhibited yellowing and necrosis of the leaf and wilting of whole leaves and plants, and brown veins around potato tuber eyes were visible on cross sections. The causal pathogen was isolated and identified as Clavibacter michiganensis subsp. michiganensis (Cmm) based on physiological, biochemical, molecular and pathogenicity analyses. The obtained 16S rRNA sequences were deposited in GenBank (accession nos. MH035728.1 to MH035762.1). This is thought to be the first report of Cmm affecting potato in Russia.