Effect of drought stress on some agronomic traits in ten barley (Hordeum vulgar) cultivars

The performance of ten barley (Hordeum vulgar) cultivars was studied under drought stress. Two separate experiments were undertaken at the individual field, Guyom, Shiraz, Iran in a randomized complete block design with three replications. Every one of the experiments was in the same condition and the only existing difference among them was stopping the irrigation in one of the experiments at blooming stage till complete maturity stage. Plant height, spike length, awn length, biological yield, seeds number spike-1, spikles number plant-1, harvest index, 1000-grain weight and grain yield traits were studied. Analysis of variance showed that, there were significant differences between genotypes for plant height, biological yield, spikles number plant-1 and grain yield in non-stress condition, indicating presence of genetic diversity among them for these traits. Genotype effects were significant for awn length, biological yield, seeds number spike-1, spikles number plant-1 and grain yield in stress condition. Combined analysis of variance across environments revealed that stress effects were significant for all traits. Genotypes differed significantly for all traits except harvest index and 1000-grain weight. Grain yield had the highest decrease percent of traits under drought stress condition (35.39) that it was probably due to reduce biological yield, seeds number spike-1 and spikles number plant-1 under drought stress. Stress × genotype interaction effect was only significant for seeds number spike-1, indicating that genotypes did not respond to the environments similarly. Based on the results of simple and combined analysis of variance of the studied traits, Gorgan, Kavir, Makoii and Zarjou cultivars were suitable genotypes under drought stress and non-stress conditions and Nosrat cultivar was the worst genotype under stress and non-stress conditions.