Physiochemical and Molecular Response of the Grafted ‘Bidaneh Ghermez’ Grape Cultivar on Native Rootstocks to Identify Tolerant Combination to Drought Stress in Vineyard Conditions

Drought stress is one of the most important limitations in the production of agricultural products and especially horticulture in different parts of the world and Iran. The climate changes that have happened in the last few years, it is possible to provide sustainable production of grapes in water stress conditions by examining and selecting cultivars that tolerate to drought stress. For this purpose, an experiment from 2018 to 2022 in the form of split plots in the form of randomized complete blocks with 3 replications in garden conditions to investigate the effect of changes in soil water potential on the morphological, physiological and biochemical characteristics of grafted cuttings on cultivar traits Tolerant to sensitive 7 grape ( Vitis vinifera L.) cultivars were carried out. The treatments included 7 selected grape varieties (‘Bidaneh Ghermez’, ‘Bidaneh Sefid’, ‘Rashe’, ‘Sahani’, ‘Kare Royeh’, ‘Moulai’, and ‘Chafte’) as the base and red quince cultivar as scion and three levels of drought stress including humidity. Agricultural (control), 75% (moderate stress) and 55% (severe stress) were based on agricultural moisture discharge. The results showed that with more severe water stress, the amount of proline, ABA, activity of catalase and peroxidase, the expression of CBF4 , NCED3 , and DHN1 genes increased, as well as the amount of total chlorophyll were decreased. In this experiment, the highest proline, abscisic acid, catalase, peroxidase, NCED3 , CBF4 and DHN1 gene expression were observed in this experiment under severe stress treatment. In general, ‘Bidaneh Ghermez’ cultivar grafted on the rootstocks of ‘Chafte’, ‘Moulai’ and ‘Kare Royeh’ had a higher potential for tolerance to drought stress than other grafted combinations tested in most of the traits.