Assessment of Genetic Divergence and Character Association Studies on Germplasm Accessions of Rice (Oryza sativa L.)

Abstract

In this study, fifty-five rice germplasm accessions were used along with five checks, namely IR64, Swarna, Jaya, DRR Dhan 42 and MTU1010, for evaluating genetic variability, heritability and genetic advance during kharif 2023. The analysis of variance revealed extremely large genotype differences for each of the 16 traits under investigation. The highest heritability measures were found in number of filled grains per panicle followed by paddy breadth, paddy length:breadth ratio, brown rice length:breadth ratio, 100 seed weight, paddy length, plant height, brown rice breadth, number of effective tillers per plant, brown rice length, number of unfilled grains per panicle, grain yield per plant, panicle length, and harvest index. High heritability with high genetic advance shown by characters such as plant height, number of filled grains per panicle, paddy length and brown rice length this indicates that the heritability is due to additive gene action and is found least influenced by environment. Hence, the desirable characters with high heritability coupled with genetic advance can be used for selection. Grain yield per plant exhibits a positive and highly significant correlation with the days to 50% flowering (0.383), number of effective tillers per plant (0.315), number of filled grain per panicle (0.219) and paddy length (0.219). In terms of direct effect, paddy length (4.735) shows the highest impact, followed by brown rice length (1.183), number of filled grain per panicle (0.578), days to 50% flowering (0.347), panicle length (0.135), harvest index (0.082).