VIR potato collection as a source of improvement of economic-valuable traits and resistance to pathogens “black leg” and “ring rot”

There is a worldwide problem caused by pre- and post-harvest potato losses due to bacterial diseases. Annual yield losses due to them are 10-15% and can exceed 50% in epiphytotic years. Currently, none of the commercial potato varieties are highly resistant to bacteriosis, as this trait was previously insufficient in most existing breeding programs. In recent years, potato losses due to black leg and ring rot have increased significantly in all countries of the world, including Russia, which increases the demand for bacteriosis-resistant potato varieties as well as effective methods of identification of affected potato samples during storage. The aim of the study is to monitor potatoes from the collection of N.I. Vavilov All-Russian Institute of Plant Industry Genetic Resources (VIR) for the presence of pathogens of Pectobacterium and Dickeya species, strains of which cause the disease “black leg”, and the bacterium Clavibacter michiganensis subsp. sepedonicus (Cms), which causes the disease “ring rot”, and to evaluate a number of economic-valuable traits of potatoes in the isolated resistant samples. We carried out visual evaluation of tubers for the presence of lesions caused by the suspected pathogens. Differential diagnosis by real-time PCR for the presence of the studied diseases was performed on the selected material. As a result of the study, most of the samples of the collection showed resistance to these pathogens, but weakly resistant forms were also found, showing the presence of complex infection. The research results can be used in future breeding programs on plant resistance to various diseases.