Drought resistance of grape varieties of various ecological and geografical origin

Abstract

The article presents the results of the study of drought resistance of various grape varieties in the parameters of water regime and content of pigments. The objects of research were the grape varieties (interspecific hybrids) of the following origin: European-American (Dostoynyi, Krasnostop AZOS, Vostorg), Western European (Aligote), Eastern European (Zarif), Euro Amuro-American (Krystall). The aim of research was the comparative evaluation of resistance of grape varieties of different ecological-geographical origin to elevated temperatures and low water availability in the conditions of Anapa-Taman area, and selecting the most valuable genotypes. It was established that by the end of summer, the water content of leaf tissues decreased to varying degrees in all grape varieties, depending on their biological peculiarities. In the Kristall, Dostoyny, Krasnostop AZOS varieties, the water content of the tissues decreased to a lesser extent (by 4.0 - 4.1%) in comparison with Zarif and Aligote varieties (by 6.8 and 7.2 %, respectively). Kristall, Dostoyny, Krasnostop AZOS varieties showed the highest rates of the ratio of bound and free forms of water during the summer (2.01-2.50) due to the increased content of bound water. Same varieties are marked by a stable amount of chlorophyll content (a+b) during the summer, with some tendency to increase by 1,07- 1.18 times in August, and the increase in the proportion of carotenoids in the pigment complex, indicating an active adaptation of these varieties to drought and high temperatures. These parameters can be used as diagnostic characteristics to assess adaptive capacity of grapes.