Genetic variability, heritability and correlation studies in half sib recurrent families of CIMMYT maize population CZP-132011

摘要

Recurrent selection is a vital selection method for improving the traits of interest in maize crop. This research was carried out to estimate genetic variability, heritability, index of variation and genotypic and phenotypic correlations among half sib recurrent families for various traits. Sixty four half sib recurrent families were evaluated in 8×8 lattice square design with two replications at Cereal Crops Research Institute CCRI, Pirsabak during 2017. Results showed highly significant differences among the half sib families for all the studied traits. High heritability (h2 0.60) were recorded for all traits except plant height and ear height which exhibited moderate heritability. High index of variation (I.V 1) was observed for all traits. After completion of one cycle of recurrent selection in half sib families, the percent gain cycle-1 was recorded negative for physio-morphic traits, while for grain yield the percent gain cycle-1 was positive. All physiological traits showed non significant negative genotypic and phenotypic correlation with grain yield except days to 50% silking. The magnitude of genotypic correlations were higher than phenotypic correlations for studied traits, which means that selection for these traits will improve grain yield. The study also observed that correlations as well as heritability were suitable as models for yield improvement and selection for best families. Traits that had higher heritability and positive correlation with grain yield may be considered as important traits in selection programme aiming to maize yield improvement and the breeder may consider these traits as main selection criteria.