Study of genetic variability based on yield and its attributing traits in Maize (Zea mays L.)

Abstract

Genetic variability, heritability, and genetic advance as percentage of mean (GAM) are crucial parameters in crop improvement. Hence, to estimate these parameters, this study evaluated 147 maize inbreds for grain yield and its attributing traits during the rabi seasons of 2015-16 and 2016-17 at RMR&SPC, Begusarai, Bihar. The analysis of variance revealed highly significant differences (P<0.01) among inbred lines for all traits studied. Traits exhibited varying levels of variability, heritability, and GAM among the inbred lines, with phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) ranging from low to moderate. The PCV was marginally higher than GCV values for majority of the traits. Anthesis silking interval (ASI) and ear height exhibited the highest GCV and PCV values, indicating their higher genetic control and high potential for selection. High heritability coupled with high GAM was recorded for grain yield, 100-kernel weight, plant height, grain filling duration (GFD), ear height, kernel per row, kernel rows, ear length, and ASI, indicating their higher additive gene effects, aiding to improved selection efficiency. Significant positive correlations of GFD with flowering traits suggest the opportunity for their simultaneous improvement. Path analysis revealed high positive direct effects of days to maturity, 100-kernel weight, ear length, and kernels per row on grain yield. Cluster analysis grouped inbred lines into three major clusters, revealing enormous diversity among them. Such diverse inbred lines can be utilized as parents for development of superior maize hybrids.