Influence of weather conditions on the variability of physiological leaf parameters in pear cultivars

Abstract

The results of the study of the adaptation potential of perennial fruit crops depending on climatic changes are presented. The physiological state of some pear varieties during summer periods in 2021, 2022 in the fruit plantations of the Krasnodar Territory were evaluated. Two Russian varieties (Flamenko, Luberskaya) and two European varieties (Conference, Williams) were studied. An experiment on artificially drying freshly harvested pear leaves at constant room temperature was conducted to amplify the negative effects of summer stressors. The relative water content of leaves and electrolyte leakage were determined before and after the stress according to generally accepted methods. It was found that relative humidity is an important factor for normal leaf development, and the change in its values in the summer months correlated with the variability of values of the stress parameter of pear leaves - electrolyte leakage. It was found that the widespread European variety Conference was the most susceptible to the effects of artificial stress. After a short drying period, this variety was characterized by a sharp increase in the electrolyte leakage to ~36 % on the background of a significant decrease in the relative water content in the leaves (71–73 %), due to the development of oxidative processes, leading to a violation of the integrity of cell membranes. Russian varieties Flamenko and Luberskaya, as well as the European variety Williams, on the contrary, by the studied physiological parameters had no strong differences (the change of physiological parameters was from 1.1 to 1.3 times), which allowed them to be identified as more resistant varieties to this type of stress exposure.