Combining ability and reciprocal effects for physico-chemical grain quality characteristics in maize

The gene action involved in the inheritance of four physico-chemical grain characteristics, i.e. starch content, gel spread, gelatinization time and temperature, in maize (Zea mays) was studied in a six-parent diallel cross. The experimental material consisted of parents, Fls and reciprocals. Additive and non-additive gene actions were observed to significantly influence the variation of starch content and gel spread with the additive gene action being more pronounced, implicating the effectiveness of selection for increased starch yield through a recurrent selection procedure. The reciprocal effects were equally significant for grain starch content, an indication of the importance of cytoplasmic effects. Variability of specific combining ability was more pronounced for time of gelatinization, whereas reciprocal effect accounted for greater variability in differences due to temperature of gelatinization. Parents BC 63 C2 and TZB-SR-SE expressed more favourable genes for increased grain starch content, limited gel spread and quicker gelatinization.