ارزیابی ژنوتیپ های گندم دوروم در شرایط آبیاری و تنش خشکی

The use of high yielding and resistant to drought stress cultivars in crops is one of the proper way to incorporation other water deficit management methods. This study in order to evaluate grain yield and morphological traits, an experiment was conducted with 100 genotypes of durum wheat which were planted based on lattice design with three replications under normal and drought stress conditions at the Agricultural Research Station in Varamin. The results showed that total dry matter have a highest positive direct effect on grain yield, whereas, grain yield filling period had the lowest effect and grain yield filling period via harvest index had the positive indirect effect on yield. Under stress condition, peduncle length had the highest positive direct effect on grain yield whereas, spike number, plant length, total dry matter, and date from germination to maturity had negative and direct effect. Factor analysis explained 80.5 and 83.3 of the total variation under normal and drought conditions, respectively. To estimate better grain yield, drought tolerance indices were determined and genotypes 3, 45 and 21 were identified with the lowest value of the indices MP, GMP and STI that were for drought condition while genotypes 45, 21, 71, 34, 78 had the highest value of the mentioned indices and were suitable for both conditions. Cluster analysis grouped genotypes into four clusters in both conditions which confirmed the results of stepwise regression as well as path analysis that could separate genotypes with high grain yield from others as well as traits affecting yield compared to other traits.