Genetic Analysis of Protein Quality Traits in Quality Protein Maize (Zea mays L.)

Abstract

Quality Protein Maize (QPM) possesses enhanced nutritional quality due to increased lysine and tryptophan content. The present study aimed to investigate the inheritance pattern and genetic variability of protein-related traits in QPM using diallel analysis. Eight QPM inbred lines and their hybrids including reciprocals were evaluated across three growing seasons. Significant variation among genotypes, seasons, and genotype × environment interactions was observed for protein content and associated kernel quality traits. Graphical analysis revealed predominance of over-dominance and non-additive gene action for several quality traits. The dominance variance components were generally higher than additive variance for protein content. Significant reciprocal effects were also observed for certain traits, indicating maternal influence. The study suggested that exploitation of heterosis and careful parental selection could effectively improve nutritional quality in QPM. The identified promising inbreds and hybrids may serve as valuable genetic resources for future QPM breeding programmes.