evaluation of bread wheat genotypes for drought tolerance

for identifying drought tolerance genotypes 29 wheat genotypes as cultivar factor and irrigation and non irrigation treatments as an irrigation factor in a split block design with 3 blocks were planted at a research filed of college of agriculture, tehran university, iran. there was a low and non significant correlation (r=0.35) between yield at non irrigating (ys) and yield at irrigating (yp) condition. the low correlation implies the independence of yield at two conditions. for identifying tolerant genotypes the indexes of sti, tol, ssi, mp, harm, ti and gmp were used. the first two components explained 97% of variation. based on the coefficients of components the first and second components were considering tolerance and sensitivity respectively. using the biplot analysis genotypes roushan, inia, kavir, alvand, ws-82-6, ghods, ws-82-9 and back cross of roushan were identified as tolerant and omid, ghafghaz, marvdasht, navid and tajan were detected as sensitive to drought.