Studies on combining ability for grain yield and harvest index over environments in breadwheat

Combining ability studies on grain yield per plant and its important component of harvest index from an 10 x 10 half-diallel cross of wheat over three environments each at two locations indicated that both goa and soa variances were important for controlling the traits. Additiw gene effect in F₂ and non-additiw gene effect in F₁ was of greater importance in the genetic control of traits. gea x E and sea x E interactions exhibited greater importance of environment in influencing the variances. Raj 1482 and HD 2204 were good general combiners for both grain yield and harvest index. The most consistent cross for high sea effect was Kharchia 65 x Chiroca which showed high sea under all the situations for the traits studied. The best crosses for grain yield were the combinations of Indian x exotic types and all these crosses also exhibited high harvest index. Diallel selectiw mating system, which exploit both additive and non-additiw gene effects, simultaneously, could be useful in the genetic improwment of the characters studied.