Inheritance of the grain number per spike in diallel cross of 5x5 bread wheat cultivars

Abstract

This study examined the mode of inheritance and the influence of genes on the grain number per spike in F1 generations, in 5x5 half diallel crosses of wheat cultivars. The results of the combining ability analysis did not indicate significant differences among the parents for general combining ability (GCA) and crosses for specific combining ability (SCA) for the grain number per spike. The GCA/SCA ratio tilted in favour of the SCA in this trait, which indicated the preponderance of non-additive gene, i.e. dominant effects in the genetic control of grain number per spike. Components data of genetic variance and regression analysis indicated a greater role of the dominant component in the grain number per spike inheritance. The regression line intercepts the Wr axis below the origin in F1, indicating over-dominance over an average of all arrays.\rKeywords: combining ability, components of genetic variance, gene effects, genetic inheritance, grain number per spike, regression analysis, wheat