Аннотация:Using the line x tester analysis (Sing and Choudhary, 1979), we studied the combining ability, gene effects and mode of inheritance of grain weight per spike and harvest index, using 5 females, 3 testers and 15 hybrids of durum wheat. The results of the study show that non-additive genes play the more important role than additive in the inheritance of grain weight per spike and harvest index. The mode of inheritance of characters under study depended on the cross combination and the year of growing. In most cases the mode of inheritance was dominant. The estimates of general combining ability (GCA) pointed out that none of the genotypes in the first year of research had the significant GCA for grain weight per spike, while in the second year the best combiner was Kunduru. For the harvest index the best general combiner, in the first year, was Monodur, while in the second year the best combiner was Mexicali 75. In majority of the cases positive specific combining ability (SCA) effect were usually associated with crosses of two genetically divergent parents having at least one parent as a good general combiner.
