Genetic deciphering of various morphological and agronomic traits under DSR conditions in Rice (Oryza sativa L.)

Water scarcity, labor shortages, and climate variability threaten the sustainability of conventional transplanted rice cultivation, necessitating the adoption of alternative establishment methods such as dry direct seeded rice (DDSR). The success of DDSR depends largely on the availability of rice genotypes possessing traits that ensure early crop establishment and stable yield performance under aerobic soil conditions. The present study aimed to assess genetic variability and identify key yield-contributing traits among rice genotypes suitable for DDSR environments. Thirty rice genotypes comprising varieties and advanced cultures of PJTAU, Telangana, were evaluated during Kharif, 2021 at Agricultural Research Station, Kampasagar, using a randomized block design with three replications. Observations were recorded for nine quantitative traits, and estimates of phenotypic and genotypic coefficients of variation, heritability, and genetic advance were computed using standard statistical procedures. Analysis of variance revealed significant differences among genotypes for all traits studied, indicating substantial genetic variability. Phenotypic coefficient of variation exceeded genotypic coefficient of variation for all characters, reflecting environmental influence on trait expression. High variability was observed for seed vigour index, number of grains per panicle, and test weight. High heritability coupled with high genetic advance as percent of mean was recorded for seed vigour index, grains per panicle, test weight, and number of effective tillers per square meter, suggesting the predominance of additive gene action and effectiveness of selection. The results indicate that these traits can serve as reliable selection criteria for improving grain yield under dry direct seeded rice conditions.