Expression of R1 and PR1 genes in leaves of belarusianbreeded potato (Solanum tuberosum L.) varieties with different resistance to late blight

The dynamics of R1 and PR1 gene expression in leaves of potato (Solanum tuberosum L.) highly resistant cultivar Vectar and susceptible to late blight cultivar Uladar under normal conditions and after 3-day infection with Phytophthora infestans (Mont.) de Bary was studied. In the absence of infection, the expression of R1 was detected in the leaves of the Vectar, which was slightly increased after infection of leaves with late blight. In the susceptible Uladar R1 expression was not detected in either healthy or infected leaves. PR1 expression in the Vectar was present in the cells of uninfected leaves and increased during infection. The Uladar was characterized by a significantly lower level of PR1 expression in uninfected and infected leaves as compared to Vectar, but activation of PR1 expression in response to the pathogen attack was more significant in the Uladar than in the Vectar. The exogenous ethylene donor ethephon has a stimulating effect on expression of R1 in the Vectar and expression of PR1 in both cultivars. Exogenous salicylic acid has a significant positive effect on the expression of R1 and PR1 in the Vectar, but inhibited the accumulation of PR1 transcripts in the Uladar. The synthetic brassinosteroid epin has an inhibitory effect on the transcription of R1 and PR1 in both cultivars. The obtained data reflect general and cultivar-specific patterns in defense responses at the level of relative expression of the studied genes. The obtained expression profiles of the R1 and PR1 genes in potato varieties sensitive and resistant to the action of phytopathogenic microflora, against the background of the simultaneous action of phytohormones, can become the basis for an early assessment of the sensitivity of breeding potato varieties to the action of the specified microflora.