Genetic diversity of medium duration rice genotypes (Oryza sativa L.) under irrigated condition

Abstract

An experiment was conducted during kharif season of 2023, at BTC college of Agriculture and Research Station, Bilaspur, Indira Gandhi Krishi Vishwavidyalaya, Raipur, Chhattisgarh. In this experiment, fifteen medium duration rice genotypes were used. The research was conducted in randomized block design (RBD) with three replications. The major objective of research conducted was evaluation of genetic variability parameters among genotypes, estimation of correlation coefficient analysis for yield and among yield attributing characters, path coefficient analysis and estimation of genetic divergence among medium duration rice genotypes. The analysis of variance reported the presence of ample amounts of variability among all genotypes for all traits studied. High to moderate estimates of GCV and PCV were observed for traits like yield per plot (q/ha) followed by, L/B ratio, 1000 grain weight (g), panicles per plant and tillers per plant indicating the importance of selection for improving the grain yield. Further, high heritability coupled with high genetic advance as per cent of mean was also observed for 1000 grain weight (g), yield per plot (q/ha) and L/B ratio. These characters are assumed to be regulated by additive gene action and selection for these traits can be rewarding. Analysis of correlation coefficient indicated high positive and significant correlation of yield per plot (q/ha) with spikelet fertility, panicle length, panicle per plants, 1000 grain weight (g) and tillers per plant. Hence, these characters are helpful to determine the higher grain yield and can be used as selection criteria. Path analysis reveal that the traits like days to maturity, spikelet fertility (%), tillers per plant and L/B ratio showed positive direct effect on yield per plot (q/ha). Thus, these characters can be used for improvement of grain yield in medium duration rice genotypes. For genetic diversity analysis 15 rice genotypes were grouped in six clusters. Cluster I was the largest cluster. Cluster V and VI had maximum inter cluster distances. The maximum inter cluster distance revealed that using parents from these clusters in a hybridization programme will result in a higher frequency of better segregants or desired pairings, which is important for the generation of valuable varieties. The contribution of traits to divergence was greatest for yield per plot (q/ha), 1000 grain weight (g) and plant height. Genotypes HRI-209, RRX-338, PHI-20106, HRI-211 and NDR-359 were found to be the top five promising genotypes for yield and yield contributing traits. Hence, these genotypes can be utilized for further selection process.