Exploring genetic variability and association in QPM maize (Zea mays) inbred lines

Variability and association studies help to assess the variation among the genotypes and interactions between grain yield and its component traits for enhancing the usefulness of selection. In view of this, the present experiment was conducted at Maize research farm TCA, Dholi, DRPCAU, Pusa, Samastipur, Bihar using 25 inbred lines of maize for various traits to determine the extent of variability and association between these lines for different characteristics. Traits including plant height, ear height, ear length, ear girth, number of kernels per row, harvest index, tryptophan content and lysine content, exhibited high heritability and genetic advance as percentage of the mean. Grain yield showed significant positive associations with ear length, ear girth, number of kernel rows per ear, number of kernels per row and harvest index while it exhibited negative association with plant height, ear height, days to 75% brown husk, protein, lysine, and tryptophan content. Furthermore, certain traits, such as ear length, ear girth, number of kernel rows per ear, number of kernels per row, harvest index, days to 50% silking, and ear height, had a direct positive effect on grain yield. Therefore, selecting these traits directly would be desirable for future hybridization endeavors.