Evaluation of morphophysiological traits and drought tolerance indices in some advanced durum wheat (Triticum durum L.) lines under supplementary irrigation and irrigation conditions

The development of food conversion industries has revealed the necessity of increasing the production of durum wheat in the country and, on the other hand, environmental stresses are responsible for decreasing the yield of crops. In order to compare 12 advanced durum wheat lines in drought tolerance, a randomized complete blocks design with four replications in two conditions (without irrigation and supplemental irrigation) in the crop year 1393-94 at Gachsaran dryland research station were conducted and morpho-physiological traits such as plant height, spike length, peduncle length, grain filling period, number of plants per square meter, 1000 seed weight and grain yield were evaluated. Results showed that all assessed traits in genotypes (except peduncle length) showed a different reaction to supplementary and without irrigation conditions, which indicates high genetic diversity among studied genotypes. Regarding most traits, Ter line was the most susceptible genotype to drought in both supplementary and without irrigation conditions. Regarding to GMP and STI indices, Ter, Icajihan and Aghrass lines were the most susceptible genotypes. Cluster analysis in both supplementary and without irrigation conditions classified lines into four groups, but tolerated lines did not get together. In general, according to yield and tolerance indices, Icajihan line was the most suitable genotype for cultivation in non-irrigated conditions.