The inheritance of diastatic power and alpha-amylase contents in spring barley

In a diallel cross of 13 spring barley varieties, non-allelic interactions interfered with the analysis of diastatic power. Regression of W r on V r was less than unity both in the full experiment and in the sub-set of two-row varieties. The simple additive-dominance model was adequate for the analysis of alpha-amylase. Regression of W r on V r indicated directional dominance, increasing alphaamylase. For both characters non-additive variance was detected and the effects of directional dominance, asymmetry of gene distribution and SCA were evident. Significant GCA effects were also present. No serious obstacles to the improvement of either character in adapted two-row varieties were apparent.