Response of some wheat genotypes to drought stress by indices of drought resistance

In order to identify the effective traits of performance and the best index of drought resistance on bread wheat in cold regions of Ardabil province, an experiment was conducted on 10 wheat crop in a randomized complete block design with three replications at the research station of Islamic Azad University of Ardabil in 2011. Genotypes were cultured in the form of separate design with normal irrigation and drought in last season. The common irrigation was cut off by the end of the season and the other irrigation from the pollination stage in one of the parts. The variance analysis results showed that stress reduced most of traits and was observed the highest reduction in yield. The study of the index of drought resistance, drought tolerance (STI), the geometric mean of productivity (GMP) and the productivity mean (MP) had highly correlation with potential yield (YP) and yield in stress condition (YS), they were recognized the most resistant genotype as the best index and genotypes C-78-14 and Marvdasht with the highest yield. Two main components justified 97.7% of the variations with principal components analysis on tolerance indices to drought. Gascogne was identified as the weakest cultivar in both stress and normal conditions.