GENETIC VARIABILITY AND HERITABILITY IN GLADIOLUS (GLADIOLUS GRANDIFLORA L.) FOR YIELD TRAITS

Variability within a crop species is crucial for effective selection, as it forms the basis for identifying traits that can be improved through breeding.In the present study, forty gladiolus (Gladiolus grandiflora L.) genotypes were evaluated for thiry-one key traits to estimate genetic variability, genetic parameters and trait associations.The results indicated that the phenotypic coefficient of variation (PCV) was generally higher than the genotypic coefficient of variation (GCV), suggesting the influence of environment on trait expression.Traits such as number of spikes per plant (GCV: 38.06), number of corms per clump (GCV: 33.48), days for floret opening (GCV: 29.88) and vase life (GCV: 29.63) exhibited high GCV values, demonstrating substantial genetic variability.Heritability estimates were notably high for spike length (99.95%), plant height (99.86%), and days to first floret opening (99.77%).The highest genetic advance as percent of the mean was observed for number of spikes per plant (75.23%) and number of corms per clump (61.64%), indicating presence of additive gene action.Genetic advance values were also significant in traits like number of spikes per plant showing a high genetic advance of 1.11 and number of corms per clump displaying a genetic advance of 1.09 further supporting potential for improvement through selection.Genotypic coefficients variation were higher than phenotypic coefficients variation, suggesting that trait associations were mainly governed by genetic factors.Days to first floret opening had most significant positive direct effect on number of spikes per plant, highlighting this trait, along with the number of spikes per plant, as key targets for yield improvement through selection.