Genetics of quality and agronomic traits in hard endosperm maize

Abstract

SUMMARYHard endosperm maize (Zea mays L.) is useful for industry and for human consumption. The objective of the present work was to study the inheritance of quality traits in hard endosperm maize. Three flint and three dent inbreds, F1 of their diallel crosses, F2s and backcrosses to each parent were evaluated for grain yield and quality traits (flotation test, flour-milling test, grain damage (GD) index and grain density). Genotypes and genotype×environment interactions were significant for most traits. A genetic model including additive, dominance and epistatic effects explained most of the genetic variation for the traits. Additive effect mean squares were larger than those due to dominance effects, except for grain yield and GD. Partition of the dominance variance into average, general, and specific dominance components revealed that the average dominance related to heterosis was the most important. Additive×additive epistatic variation was smaller than additive and dominance variation for quality traits. Some inbreds displayed sufficient potential to be used in hard endosperm maize breeding programmes. The average dominance effect was favourable for most of the quality and agronomic traits. Breeding programmes for improving quality in hard endosperm maize would be most efficient if both additive and dominant effects are capitalized on.