ASSESSMENT OF GENETIC VARIABILITY AND ASSOCIATIONS FOR GRAIN YIELD IMPROVEMENT IN AUTUMN MAIZE (ZEA MAYS L.) HYBRIDS

Abstract

Maize (Zea mays L.) is a vital crop particularly in developing countries, where it plays a critical role in ensuring food security. Current research was conducted at Maize Research Station, Ayub Agricultural Research Institute, Faisalabad during Kharif 2023. Sixteen maize hybrids were evaluated for grains yield and associated traits using a randomized complete block design with three replications. The objective was to assess genetic variability, heritability, genetic advance and trait correlations analysis. The results indicated statistically significant values (p < 0.01) among the sixteen hybrids for all twelve traits. Traits such as ear height (17.19%, 13.89%), grain yield (15.68%,12.78%) and grains/row (14.65%, 14.14%) exhibited a high value of phenotypic coefficient of variation (PCV %) and genotypic coefficient of variation (GCV %). High heritability percentages were recorded for cob length (99%), shelling percent (99%), 1000 grain weight (98%), grain length (97%) and grain width (97%) indicating negligible environmental influence and implying their suitability for selection in breeding programs. A significant positive correlation was observed between cob length and 1000-grain weight (0.74*), indicating increase in cob length can enhance the grain weight and ultimately grain yield. Grain yield showed nonsignificant association with all traits suggesting indirect selection of traits might contribute to grain yield improvement. Negative correlation between cob girth and grain thickness (-0.62*) suggested that only one trait at one time can be improved. Among hybrids, FH-1731 and FH- 1400 demonstrated superior grain yield and could be used for enhancing maize productivity.