Peroxidase activity (POX) changes specifically in the case of heat compared to drought or optimal conditions. At the same time, it was found that, in the case of heat, the descendants from the TAV or TMV infected plants (except Rufina) indicated significantly higher values for POX-up to 2.2 times more than the control for the TAV variants and 1.33 times for TMV. The TAV variants, also expressing significantly higher values compared to TMV. In the case of the variants exposed to drought, significant differences were established for the TMV variant - the values of the POX indices represented 0.84-1.5 from the value of the control under similar conditions and for VAT 0.68 -1.67. Three-factor Anova analysis established the significant influence of Genotype, Stress and Virus factors, as well as their interaction on POX variation. The specificity of the reaction of genotypes to heat compared to Drought or optimal conditions, in particular in the case of offspring from virus-infected plants was also confirmed by cluster analysis.