Sensitivity Wheat Genotypes for Grain Yield and Quality Traits to Drought Stress

Drought stress influences both yield and quality traits of wheat genotypes. This study evaluated the grain yield, its components and quality traits to drought stress with comparison normal condition. Ten-spring wheat genotypes were planted at season of 2002-3 in Agricultural Research Center of Western Azerbaijan Province, North Western of Iran. To determine the effects of drought stress on grain yield and its components, protein percent, flag leaf area, relative water content, hardness index and water absorption by flour, which were arranged in two randomized complete block designs with five separate replications under normal and drought stress. Analysis of variance showed that, all traits were significant differences at minimum probability level (P = 0.05) in two conditions. Drought stress induced reduction in grain yield due to reduction spike per m2 and 1000KW. In addition, gluten index was decreased. Drought sensitivity indexes (DSI) for grain yield and gluten index were accounted. Genotype of Khazar was the lowest DSI for grain yield and high value for gluten index. In opposite, Mahuti, Falat and Kavir were the lowest and highest DSI for grain yield and gluten index, respectively. Genotypes of Roshan and Bafghi were the genotypes with low grain yield potential and high values of gluten index. It seems that Roshan and Bafghi were tolerant genotypes with high quality traits. Except of Arvand that was softer grain, other genotypes were harder. Damaged starch in hard grains is more and therefore flour, which comes from hard grains, has more water absorption capacity. Correlation coefficient between grain yield and other traits showed that there was a positively correlation with flag leaf area under drought stress (r = 0.81, p =0.01), but in normal conditions didn’t significant. Therefore, this trait may be a useful criterion for indirect selection genotypes for drought tolerance.