In a two years experiment, 149 bread wheat recombinant inbred lines (RILs) derived from a cross between of US variety Yecora Rojo and Iranian local genotype NO.49 along with parental lines were grown under well-watered and water deficit stress conditions, imposed at panicle initiation stage. Eight drought tolerance indices including Stress Tolerance Index (STI), Mean Productivity (MP), Geometric Mean Productivity (GMP), Stress Tolerance (TOL), Stress Susceptibility Index (SSI), Yield Stability Index (YSI), Relative drought index (RDI), and Drought resistance index (DI) were used to identify high yielding and drought tolerant RILs. Significant and positive correlation was found between grain yield under stress condition (Ys) and STI, MP, GMP, SSI, YSI, RDI, as well as DI indicating the efficiency of these indices for screening drought tolerant genotypes. Grain yield under drought stress condition was associated with yield under well-watered condition (r = 0.66** and 0.84** in 2009 and 2010, respectively). Reduction in plant height due to water stress was negatively correlated with grain yield, biomass, spike length, grain number per spike, and 1000 grain weight in 2009 and yield reduction percentage in 2010. Among the drought tolerance indices, GMP showed higher correlation with grain yield (r = 0.94** and r = 0.97**), biomass (r = 0.73** and r = 0.81**), and harvest index (r = 0.7** and r = 0.76**) under stress condition in 2009 and 2010, respectively. The biplot based on components showed that the most appropriate indices to identify genotypes were GMP, MP, and STI.
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