GENETIC ANALYSIS FOR EARLINESS AND YIELD TRAITS IN MAIZE

Five white kernel maize inbred lines with distinct genetic make-up were crossed in a 5 x 5 complete diallel fashion during spring season 2011 at Cereal Crops Research Institute (CCRI), Pirsabak-Nowshera, Pakistan. The resulting 20 F-1 hybrids, their five inbred lines and two checks hybrids (OPV 'Jalal' and 'Pioneer hybrid 30K08') were further evaluated during subsequent summer season 2011 at four locations. Present research was designed to study the genetic mechanisms controlling various earliness and yield traits through Hayman's diallel approach. Genotypes, locations and genotype by environment interactions (GEI) showed significant (p <= 0.01) differences for all the traits studied. Significant genotypic differences for various traits justified to carryout the Hayman's genetic analysis. For adequacy, the additive-dominance model was adequate / partially adequate for various traits at all the locations. According to genetic analysis, the key components of genetic variances i.e., additive (D) and dominance components (H1, H2) and average degree of dominance revealed that dominance components were predominant and overdominance type of gene action played an important role in the inheritance of all the traits at different locations. Genetic analysis further revealed unequal proportion of positive (U) and negative (V) alleles in the loci (II2更多