Evaluation of Tolerance to Drought Stress in Some Bread Wheat Genotypes

In order to evaluate of some breed wheat drought tolerant genotypes, 14 different genotypes based on a randomized complete block design (RCBD) with 3 replications were evaluated under non-stress and drought stress conditions in 2010-2011 growing season. For detection genotype tolerance in grain yield in drought stress (Ys) and non-stress (Yp) conditions were used some drought tolerance indices such as stress Tolerance (TOL), Mean Productivity (MP), Stress Susceptibility Index (SSI), Geometric Mean Productivity (GMP), Stress Tolerance Index (STI), Harmonic Mean (HAM) and Yield Stability Index (YSI). Drawing bi-plot according to two principle components was shown that the genotypes No. 13, 3 and 8 were placed in near to MP, GMP, HARM and STI vectors. Based on drought resistance indices genotypes No. 13, 3 and 8 with high grain yield in two conditions and high amount of STI were proposed as drought tolerant genotypes. Based on cluster analysis the above genotypes were placed in one group