Inheritance of Protein and Yield of Grain and Stover in Maize1

Abstract

Ten flint and nine dent inbred lines of maize (Zea mays L.) comprised the parental material. Four flint and four dent lines were selected for high protein percentage in the grain and good general combining ability (GCA) for agronomic traits, whereas the remaining 11 lines were selected for good GCA for agronomic traits only. The resulting 90 flint ✕ dent hybrid combinations were evaluated at two locations. Data were recorded on percent protein and protein yield of grain and stover, grain and stover yield, percent dry matter in the ear, and 1,000‐kernel weight. In the materials under study, mean squares due to GCA and specific combining ability (SCA) were significant for all traits. Genotype ✕ environment interactions involving both GCA and SCA were generally significant. Percent protein in the grain showed the highest GCA/SCA ratios, indicating that additive gene action relative to non‐additive gene action was more important in its inheritance than for the other traits. Lowest GCA/SCA ratios were observed for grain yield and protein percentage in the stover. As a result of simultaneous selection for high protein percentage in the grain and GCA for agronomic traits, the inbred line that revealed the highest positive GCA effect for protein percentage in the grain was also a significantly good general combiner for grain yield. No association was observed between percent protein in the grain and grain yield.