Grape varieties drought resistance in the Krasnodar region conditions

The purpose of research is to evaluate grape varieties of various ecological and geographical groups in terms of adaptation to drought according to physiological and biochemical parameters, to identify varieties with high adaptive resistance for cultivation in the conditions of the Anapo-Taman zone of the Krasnodar Region and use in breeding. The studies were carried out in 2018-2021 at the sites of the ampelographic collection of the Anapa Zonal Experimental Station of Viticulture and Winemaking (AZOSViV) - a branch of the Federal State Budgetary Scientific Institution SKFNTSSVV (Anapa). The objects of research are grape varieties (interspecific hybrids): European-American origin - Dostoyny, Krasnostop AZOS, Vostorg; Western European - Aligote; Eastern European - Zarif. The control was the Crystal variety of Euro-Amur-American origin. The indicators of the water regime were determined by the weight method, the anatomical and morphological structure of the leaf was determined by the method of light microscopy. The content of photosynthetic pigments was found by spectrophotometric method in 85 % acetone extract. During the summer, the varieties Kristall, Krasnostop AZOS, Vostorg, Zarif had the highest values of the ratio of bound water to free water (3.8-4.1), in contrast to other studied varieties (2.0-2.2), due to an increase in bound drought tolerance water forms. Due to the increase in the proportion of carotenoids that perform a photoprotective function in the varieties Kristall, Krasnostop AZOS, Vostorg, Zarif, the lowest values of the chlorophylls/carotenoids ratio (2.1-2.9) were found, in contrast to the varieties Dostoyny, Aligote (3.4). Evidence of the high adaptability of leaf tissues to drought in the varieties Kristall, Krasnostop AZOS, Vostorg, Zarif is the revealed signs of xeromorphic leaf structure. Varieties Crystal, Krasnostop AZOS, Vostorg, Zarif in terms of physiological, biochemical and anatomical and morphological parameters proved to be more drought-resistant in comparison with varieties Dostoiny, Aligote and are recommended for cultivation in the conditions of the Anapo-Taman zone of the Krasnodar Region and use in breeding.