Physiological and biochemical features of adaptation of the genus Vitis (Tournef) L. species to winter stress factors on the changing climate background

The purpose of the study is to identify the features of adaptation of plants of species of the genus Vitis (Tournef) L. to stressors that manifest themselves in the winter period in the conditions of the Anapo-Taman zone and are associated with climate change. The resistance of grape varieties: Crystal of Euro-Amur-American origin, Dostoyny and Krasnostop AZOS - Euro-American, Vostorg - Amur-American, Zarif of Eastern European, Aligote - of Western European origin - to climate change in the winter period 2021-2022 was studied in the conditions of the Anapo-Taman zone. In the shoots of the studied grape varieties, the total water content, the content of free, bound water were determined by the gravimetric method, protein was determined by the spectral method on a LEKISS 1207 spectrophotometer, abscisic acid, sucrose, and the amino acid proline were determined by capillary electrophoresis, the starch content in shoots was determined histochemically using an Olympus microscope. During the analyzed period, the minimum temperatures in winter increased by 6-10 °C, the temperature drop in December decreased by 10 °C, in Ja¬nuary by 12 °C, and in February by 3 °C. It has been established that after freezing in the grape shoots, the content of the bound form of water increases, protein breakdown is activated in all grape varieties under study. Varieties Crystal, Worthy, Vostorg, Zarif are characterized by a high content of the bound form of water; varieties Crystal, Krasnostop AZOS, Aligote - proline; cultivars Kristall, Vostorg, Aligote and Zarif are sucrose, which suggests different mechanisms of water-retaining capacity. It was established by the method of artificial freezing that the varieties Dostoyny, Kristall, Krasnostop AZOS are highly frost-resistant, the variety Vostorg is frost-resistant, the varieties Aligote and Zarif Vostorg are moderately frost-resistant. The low temperatures of December and February 2022 (-3, -5 °C) did not have a significant impact on the overwintering of the studied grape varieties in the Anapo-Taman zone.