ارزیابی عملکرد و اجزای عملکرد لاین‌های پیشرفته گندم تحت شرایط تنش خشکی

This study was conducted to evaluate the effects of drought stress on the yield and yield components of 169 recombinant inbred lines (RILs) in wheat (Triticum aestivum L.), using two separate lattice design (drought stress and control). Two moisture regimes normal and low irrigation (16% and 20% moisture by weight of soil, respectively) were used. Results of analysis of variance revealed significant differences among lines for all studied traits under normal conditions with the exception of number of grains per spike, grain weight in the spike. Under moisture stress conditions, the lines significantly differed for the studied traits with the exception of number of grains per spike and 1000-grain weight. Drought stress reduced the number of spike m2, number of grains per spike, grain weight in the spike, 1000-grain weight, biological yield, grain yield and harvest index. Under water non-stress compared to stress conditions, the narrow-sense heritability of harvest index was lower. In normal humidity conditions, the highest narrow-sense heritability, belonged to the number of spike per m² (77%), while under water stress condition, belonged to the grain yield (84%). Stepwise regression analysis showed that in water stress, number of spike per m² was the first variable entered into the model that explained own, 65 percent of yield variation.