Identification of sensitive and tolerant wheat genotypes to drought stress based on some physiological and phenological traits

Breeding for drought tolerance can prevent from loss of production under drought conditions. Physiological parameters can be utilized as tool for selection of genotypes with high adaption to drought stress. In this experiment, 30 bread wheat genotypes were compared in field in a randomized complete block design by measuring physiological and phenological parameters. Also, osmotic adjustment was evaluated at seedling stage for the same genotypes. According to results, water stress led to reduced leaf relative water content of the wheat genotypes. Also osmotic potential was more negative under stress condition compared with normal condition. During water stress, prematurity was observed for all genotypes. In Vierynak, Fong, Frontana, Tajan, Shiroodi and WS-82-9 the maturity date was sooner than other genotypes. Reduction in leaf relative water content in Sardari was 4.5 fold more than tolerant genotype (Vierynak). Vierynak, WS-82-9 and Frontana employed the mechanisms of escape and avoidance under drought stress. Highest yield under stress condition was belonged to Sardari, Roshan and Tous with 6, 5.46 and 5.37 t/ha, respectively. Therefore, these genotypes had more tolerance to drought stress and can be suggested to cultivate under water deficit conditions.