Diagnostics of plum resistance to the combined effects of drought and hyperthermia

The article considers the possibility of diagnosing the stability of fruit crops under the combined action of hyperthermia and drought. The objects of the study were isolated leaves of Prúnus doméstica L. of FSBSI VNIISPK breeding varieties. The purpose of the work was to assess the resistance of plum varieties to the combined effects of drought and hyperthermia on the basis of physiological and biochemical resistance markers. The products of peroxidation of membrane lipids, free proline, hydrogen peroxide and catalase activity were determined. It is shown that after the action of the stresses used in the varieties Nezhenka and Orlovsky souvenir, the accumulation of malondialdehyde and lipid hydroperoxides was significantly lower by 23.0…24.6% and 15.6…16.3% than in the varieties Skoroplodnaya and Krasa Orlovschiny by 42.1…52.3% and 36.6…41.2%, respectively. It was shown that against the background of the action of stressors, the varieties Nezhenka and Skoroplodnaya were characterized by a high degree of intensification of the antioxidant enzyme catalase and a moderate increase in hydrogen peroxide in the leaves. Thus, a slight increase in the intensity of lipid peroxidation in the Nezhenka and Orlovsky souvenir varieties in comparison with the Krasa Orlovschiny and Skoroplodnaya indicates the presence of physiological and biochemical resistance to the action of the stress factors used.