Studies on genetic diversity in Rice (Oryza sativa L.)

Abstract

The nature and magnitude of genetic divergence were estimated in 70 rice genotypes using Mahalanobis D – statistics by considering 13 quantitative characters. ANOVA revealed the presence of considerable amount of variability among the genotypes. High estimates of genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) were observed for grain yield per hill followed by tillers per hill and harvest index. High heritability coupled with high genetic advance was recorded for spikelets per panicle. Mahalanobis D analysis revealed considerable amount of diversity in the material. The genotypes were grouped into nine clusters. Cluster I and cluster III constituted maximum number of genotypes (12 each). The genotypes falling in cluster VII (2907) had the maximum divergence, which was closely followed by cluster V (2027) and cluster I (1762). The inter cluster distance was maximum between cluster VI and VII (18054) followed by cluster III and IX (12520), suggesting that the genotypes constituted in these clusters may be used as parents for future hybridization programme. Traits like spikelets per panicle; plant height and biological yield were the major contributors to genetic divergence.