Character Association Studies for Grain Yield and Kernel Zinc in Maize Hybrids

Abstract

Maize plays an important role in global food and nutritional security. Exploring trait associations with grain yield and kernel zinc concentration supports breeding strategies aimed at combining productivity with improved micronutrient content. A total of 55 hybrids including checks were evaluated in two locations and two replications to understand the relationship among grain yield, and its components including kernel zinc using correlation and path analysis coefficient.  Significant genetic variation was observed for all traits, with heritability estimates ranging from moderate to moderately high (0.35–0.60), indicating substantial scope for selection. Grain yield (YD) exhibited strong and significant positive correlations with number of ears per plot (NE), number of plants per plot (NP), plant height (PH) and ear height (EH). Path analysis revealed that NE exerted the largest direct effect on grain yield, whereas NP, PH and EH influenced yield primarily through indirect pathways, highlighting their importance as selection criteria in yield improvement. Kernel zinc concentration showed no significant correlation with grain yield (r = –0.062) and had negligible direct effects (–0.0218), demonstrating that zinc accumulation is essentially independent of yield and its component traits. These findings confirm that zinc biofortification in maize can be pursued without compromising grain yield potential, enabling simultaneous improvement of both productivity and nutritional quality.