Genetic analysis of yield and its attributing traits in advanced breeding lines of rice (oryza sativa l.) under aerobic condition

To select improved rice lines under aerobic conditions according to a selection index, degree of association between grain yield and yield attributing characters and their direct, indirect effects on grain yield, a field experiment was conducted using forty advanced breeding lines of rice during kharif season of 2024 at field of All India Coordinated Research Project, Nagpur. The examination used a Randomized Complete Block Design with two replications. All the traits exhibited highly significant differences, indicating the existence of genetic variability among the progenies. The findings revealed that traits like grain yield plant-1 exhibited highest value of genotypic and phenotypic coefficient of variability along with high heritability and genetic advance percentage of mean however, number of spikelet’s panicle-1, panicle length and 1000 grain weight displayed moderate genotypic and phenotypic coefficient of variability along with high heritability and genetic advance percentage of mean. Correlation studies revealed that grain yield plant-1 showed a significant positive correlation with plant height, number of panicles plant-1, panicle length, number of spikelet’s panicle-1, spikelet fertility and 1000 grain weight, while number of spikelet’s panicle-1 had the strongest direct positive impact on grain yield plant-1 followed by panicle length, number of panicles plant-1. The selection index based on the combination of plant height, panicle length, number of panicles plant-1, number of spikelets panicle-1 and grain yield plant-1 has the highest genetic advance and relative efficiency percentage. This indicated that indirect selection via., these traits would be more efficient than direct selection using grain yield alone. The selection index based on the combination ofGrain yield plant-1 + Plant height, No. of panicles plant-1 + Panicle length + No. of spikelet panicle-1 has the highest genetic advance and relative efficiency. This indicated that indirect selection via these traits would be more efficient than direct selection using yield alone. Therefore, the progenies SKL-19-01-120-44-32-60, SKL-19-02-77-221-98-83 and SKL-19-02-77-221-98-94 could be selected based on multiple traits selection under aerobic condition for further evaluation.