Genetic Divergence and Character Association Studies for Yield and Yield Attributing Traits in Aromatic Rice (Oryza sativa L.)

Abstract

Thirty-five aromatic rice (Oryza sativa L.) genotypes, including standard checks, were assessed in a randomized block design with three replications at CSAUAT, Kanpur, Uttar Pradesh, with the aim of investigating genetic variability, trait association, and divergence for yield and related attributes. Significant differences among genotypes were observed for all the traits studied which indicates the presence of adequate genetic variability. For most of the traits, the phenotypic coefficients of variation were higher than the genotypic coefficients of variation. High heritability along with high genetic advance was recorded for important yield components such as the number of panicles per meter square, productive tillers per plant, panicle length, and grain yield, indicating the effectiveness of selection. The correlation analysis showed that grain yield is strongly positively associated with panicle length, panicles per meter square, biological yield, and straw yield. From the path coefficient analysis, it was concluded that biological yield and harvest index have the largest direct positive effects on grain yield. Cluster analysis divided the genotypes into five distinct clusters; Clusters II and V showed maximum divergence and thus hold prospects for heterotic crosses. The genetic divergence analysis has identified RGL7040 (MTU RM 428-1-1-1), R-ASG-2019-36, Shobhini (NC), Ketkijoha (QC), and SRB-25-32-1-1 as promising parents for the breeding program aimed at improving yield and adaptability in the Kanpur region.