Ezatollah Farshadfar and Hooshmand Safari
To locate the genes controlling drought resistance and screening quantitative indices of drought tolerance, wheat substitution lines of Cheyenne (Donor) into the genetic background of Chinese Spring (Recipient) were tested in a complete randomized block design with three replications under two different water regimes (irrigated and rainfed). The results of analysis of variance exhibited significant differences between the lines for yield potential (Yp), mean productivity (MP), stress tolerance index (STI), geometric mean productivity (GMP), abiotic tolerance index (ATI), stress yield (Ys), tolerance index (TOL), yield index (YI) and stress susceptibility percentage index (SSPI) indicating the presence of genetic variation and possible chromosomal localization of the genes controlling drought tolerance. Screening drought tolerance indicators using correlation analysis displayed that the most suitable drought tolerance criteria for screening substitution lines were MP, GMP and STI. Mean comparison revealed that most of the genes controlling yield and drought tolerance are located on chromosomes 2A, 2B, 4B, 5B, 7B and 1D. Principal component analysis justified 96.10% of total variation in the data matrix. Ward’s hierarchical clustering of genotypes and biplot analysis of the first two principal components showed that most of t 2A, 2B, 4B, 5B, 7B and 1D.