Estimation of heterosis for grain yield and its related traits inwheat (Triticum aestivum L.) under leaf rust conditions

Eight bread wheat (Triticum aestivum L.) cultivars were crossedin a diallel fashion and evaluated for heterosis in F1 generation forgrain yield and other economic traits under leaf rust conditions.Highly significant differences were found among genotypes for allthe traits studied. Significant positive heterosis and Heterobeltiosiswas observed for grain yield per plant in almost all crosses.Estimates for positive significant heterosis over mid and betterparents for plant height were 68 and 32% of total crosses where as44 and 35 crosses gave significant positive increased tillers perplant over their mid and better parents, respectively. Positive andsignificant heterotic effects were measured as 11.61, 61.90, 30.67, 2.3,51.89, 126.64, 111.71 and 45.91 % from crosses SA42 x Nacozari, MH 97x Crow, Parula x Chenab70, Crow x Nacozari, Crow x Chenab70, SA42x Nacozari, MH97 x SA42 and Nacozari x Chenab for plant height,tillers per plant, grains per spike, spikelets per spike, grain weight,grain yield, biological yield per plant and harvest index,respectively.