Comparison of bread wheat (Triticum aestivum) genotypes based on drought tolerance indices

In order to study yield variation of the most tolerate genotypes of bread wheat (Triticum aestivum) against drought stress an experiment was conducted using RCB design with three replications. That was done on rain fed and irrigated land in agricultural research field of Salehabad in Ilam province (2005-2006). The most common genotypes consist of five varieties; Chamran, Atrak, Zagros, Koohdasht and Chenab were studied. Considering yield in the stress and non–stress conditions drought tolerance indices including MP (mean of productivity), SSI (stress susceptibility Index), TOL (tolerance), GMP (geometric mean of productivity) and STI (stress tolerance index) were calculated. High significant positively correlated indices were determined as selection factors of high yield potential and resistant varieties. According to drought tolerance indices Zagross and Chamran variety were found as the most tolerate and Atrak and Chanab were the most susceptible varieties examined.