Effects of drought stress on some morphophysiological traits of some Iranian and foreign commercial grape varieties

Drought is the most important abiotic stress limiting the agricultural crops growth and productivity. Grapevine (Vitis vinifera. L) tolerance to drought is higher than that of most of other trees, but there are many differences between grape varieties for drought tolerance. This study was carried out as a completelty randomized design to evaluate the tolerance of some commercial grapevine cultivars imported from the other countries and several native grapes of West Azarbaijan province. One year old seedlings of studied cultivars (Rasha, Mam Braima, Yaghooti, Askari, Khalili sefid, Fakhri, Sayani, Rish baba, At ouzum, Black seedless, Superior, Flame seedless, Thompson seedless, Fiesta and Perlette were cultivated in pots and subjected to drought treatments (35, 55 and 75 %). After a drought stress for three months, the morphological traits, such as stem fresh weight, root fresh weight, stem and root dry weight, leaf area and physiological characteristics such as chlorophyll content, RWC, leaf temperature were measured. The results of this study showed that there was a significant difference between the traits of studied grape cultivars under stress conditions. Fiesta and Block Seedless were very sensitive to drought condition, while the Khalili, Rasha, and Yaghooti cultivars were able to withstand the stress conditions. Among the imported cultivars, Perlette and Flame seedlesss showed a relatively good tolerance to drought stress.