Evaluation of biochemical parameters of tolerance to drought stress in rootstocks and cultivars of plum and prune (Prunus spp.)

Drought is one of the most threats in agricultural production worldwide, and climate change exacerbates this threat. Introducing drought tolerant cultivars and stocks is a fundamental solution. In order to evaluate the tolerance to drought of some economical rootstocks and varieties of Prunus spp., a factorial experiment was conducted in a completely randomized block design with three replications at the Horticultural Research Institute, Kamalshahr, Karaj, Iran, in 2021–2022. The first factor included vegetative rootstocks of Myrobalan C29, Penta, Tetra, St. Julien, Mariana 2624, GF677 and GN15, along with seed rootstocks of plum as a control; the second factor was varieties of Japanese plum (Simka and NO16), European plum (Zuchelo) and Greengag Prunus and the third factor was drought stress (with interruption of irrigation for 14 days) and control (without interruption of irrigation). Evaluated biochemical traits included the activity of the antioxidant enzymes catalase, peroxidase and polyphenol oxidase, proline content, soluble protein, total antioxidant, ionic leakage and relative water content. The results showed that the activity of antioxidant enzymes under drought stress conditions in Zuchelo on GN15 rootstock, were increased compared to the control. The highest proline content was observed in the NO16 variety and GF677 rootstock. According to the results, in terms of the studied traits, Zuchelo, NO16, GF677, and GN15 were introduced as drought tolerant varieties and rootstocks.