Studies of upland rice (Oryza sativa L.) for yield potential and associated traits under Bastar plateau conditions

Abstract

The present study, evaluated 57 upland rice (Oryza sativa L.) genotypes under direct seeding conditions using a Randomized Complete Block Design. Genotypes R2748-1-1, IR18A1068, JDP-1212, R2735-56-1 and IR18A1073 recorded the highest grain yields, indicating potential for selection. High heritability and genetic advance were noted for number of effective tillers per plant, number of grains per panicle, grain yield and related traits, suggesting additive gene action. PCV values slightly exceeded GCV, indicating environmental influence. Moderate to high variability was found in key yield-contributing traits. Grain yield showed significant positive correlation with traits like days to 50% flowering, number of effective tillers, flag leaf length, flag leaf width, panicle length, number of grains per panicle, test weight, biological yield and harvest index. Path analysis revealed that biological yield followed by harvest index, number of grains per panicle, flag leaf length, flag leaf width, panicle length, number of effective tillers, test weight, days to 50% flowering, days to maturity, plant height, kernel breadth, grain L/B ratio, grain length and kernel length exhibited positive direct effect on grain yield. Cluster analysis grouped the genotypes into six clusters, with Cluster VI showing the best mean performance for grain yield and contributing traits. Grain L/B ratio, kernel L/B ratio and days to maturity were major contributors to genetic diversity.