GENETIC VARIABILITY, HERITABILITY AND GENETIC ADVANCE ESTIMATES IN MAIZE (ZEA MAYS L.) GENOTYPES IN NEPAL

Eleven early maize and ten winter maize genotypes were evaluated in randomized complete block design (RCBD) with three replications at the research field of Regional Agricultural Research Station (RARS), Lumle, Kaski and National Maize Research Program (NMRP), Rampur, Chitwan, Nepal respectively to assess the magnitude of genetic variability, heritability and genetic advance for yield and yield contributing traits during summer (Kharif) and winter (rabi) seasons of 2016-2017. Analysis of variance revealed significant differences for 10 characters studied among the genotypes. The phenotypic coefficient of variation (PCV) is higher than genotypic coefficient of variation (GCV) recorded for all traits. High GCV and PCV was recorded for grain yield, thousand kernel weight and ear height. Heritability was moderate to high except thousand kernel weight in Kharif whereas number of kernel per ear showed lowest heritability in winter season. Genetic gain as percentage of mean (GAM) was greater for grain yield, thousand kernel weight, plant height and ear height. As grain yield had higher genetic advance along with high heritability in both the seasons that indicated the presence of large proportion of additive gene action for deciding this trait