Genetic and agronomic evaluation of short-season Quality Protein Maize

Abstract

Development of early-maturing hybrid cultivars of Quality Protein Maize (QPM), a hard-endosperm high-lysine maize (Zea mays L.), could provide a balanced-protein alternative feed crop for northern temperate areas. A set of inbred lines derived from QPM germplasm was used as the base population for three experiments conducted in eastern Canada: an eight-parent one-half diallel analysis, an evaluation of inbred performance, and an evaluation of resistance to Fusarium ear rot. In the diallel analysis, general combining ability effects were significant for grain yield, moisture at harvest, and kernel opacity. Specific combining ability effects were also significant and accounted for 20 and 13% of the genotypic variability for grain yield and moisture at harvest, respectively. Some QPM hybrids yielded well, but they had relatively high levels of grain moisture at harvest, indicating a need to breed for improved adaptation. Within the base population of QPM inbreds, the variation and repeatability for most agronomic traits and for resistance to Fusarium ear rot appeared to be adequate to allow development of agronomically superior QPM inbreds and hybrids for northern temperate maize growing regions.Key words: Quality Protein Maize, opaque-2, repeatability, diallel, agronomic potential, Fusarium graminearum