Genetic enhancement and association study of early generation pre-breeding restoration CBSN 25 / WRM 21-24 in hybrid rice

Rice, the present investigation was carried out to study the genetic variability, correlation, and path analysis between yield and yield contributing traits for six agronomic and three physiological traits in 32 families of the F ₃ population of cross CBSN25/WRM21-24. High PCV, GCV, heritability and GAM were recorded for a number of productive tillers, panicle length, leaf area, dry matter production and single plant yield, which indicates that these traits are highly amenable to selection. The pedigree method of selection may be utilised for further improvement of these traits. The traits viz ., number of productive tillers, panicle length, leaf area, dry matter production and spikelet fertility expressed significant associations with grain yield. All the studied traits had a direct effect on single plant yield except days to 50% flowering, spikelet fertility and chlorophyll index. At the intra family level, eight families namely 92, 95, 103, 106, 107, 113, 154 and 182 showed high values of PCV, GCV, heritability and genetic advance as percent of mean for days to 50% flowering, plant height, panicle length, number of productive tillers, spikelet fertility, chlorophyll index, leaf area, dry matter production and single plant yield. The families 4, 5, 7, 24, 53, 115 and 154 (88 plants) of CBSN 25 /WRM 21–24 showed amplification for both R f 4 and R f 3 genes, indicating their potential as restorers for the hybrid rice breeding programme.