Assessment of Genetic Variability, Heritability and Genetic Advance in Maize Genotypes (Zea mays L.)

Aim: The aim of the present research work was to estimate the genetic variability, broad sense heritability and genetic advance for various yield and its contributing characters of 39 maize genotypes. Methodology: 39 maize genotypes were sown in randomized block design and replicated thrice to evaluate various genetic parameters. The data was recorded on twelve quantitative traits including days to fifty percent tasseling, days to fifty percent silking, days to maturity, plant height, ear height, ear length, ear diameter, number of kernel rows/ear, number of kernels/row, 100kernels weight, shelling % and grain yield/plant. Results: The mean sum of squares due to genotypes for each of the 12 traits under study indicated significant differences in analysis of variance. High to moderate genotypic and phenotypic coefficients of variation as well as genetic advance were observed in the traits yield per plant, plant height, ear height, number of kernels per row, and 100-kernel weight. These findings suggest that the heritability of these traits is most likely the result of additive gene effects and that selection in early generations may be effective for these traits. On the other hand, the remaining characters days to 50% tasseling, days to 50% silking, number of kernel rows per ear, and shelling percentage were recorded with high heritability with low genotypic and phenotypic coefficient of variation and genetic advance suggesting non-additive gene action for control of these traits which provides limited scope for improvement by selection. Conclusion: Among the characters studied, grain yield, plant height, and ear height had high heritability and high values of genetic advance indicating that these characters were controlled by additive gene action and so phenotypic selection is effective for improvement of these traits.