Appraisal of genetic variability, heritability and genetic advance for quantitative traits in maize (Zea mays L.)

Maize is a staple food crop globally, contributing significantly to food security. However, low productivity due to limited genetic understanding and inadequate exploitation of variability in genotypes remains a major challenge. This study aimed to assess genetic variability, heritability and genetic advance for kernel yield and related traits to identify potential genotypes for future breeding programs. The experiment was conducted using a randomized complete block design with three replications, involving 238 diverse maize genotypes. Data on fourteen yield and yield-contributing traits were subjected to statistical analyses. Significant variation among genotypes was observed for all traits, indicating genetic diversity. The phenotypic coefficient of variation (PCV) exceeded the genotypic coefficient of variation (GCV) for most traits, highlighting environmental influence. High GCV and PCV were recorded for kernels per row, cob weight and kernel yield per plant indicating substantial variability. Broad-sense heritability was highest for cobs per plant followed by kernel yield per plant, ear height and cob weight suggesting strong genetic control. Traits such as plant height, ear height and kernel yield per plant exhibited high heritability and genetic advance, indicating the predominance of additive gene action and suitability for selection. Genotypes IGI-19-26, IL-12-11, IL-14-39, NAI-105-5, IL-17-61, IL-14-80 and IGI-19-47 demonstrated superior yield performance, making them promising candidates for maize improvement programs. These findings provide critical insights for developing high-yielding maize varieties through targeted breeding strategies.