Genetic Analysis of a Recombinant Inbred Line Population Derived from Salt-Tolerant Rice Landrace Korgut under Coastal Ecology

Abstract

Rice is an important food crop in the coastal regions of India, wherein its cultivation is challenged by various abiotic stresses such as salinity, submergence, stagnant flooding, coastal storms, and cyclones. Overcoming these challenges is vital for sustaining rice cultivation in these areas. The present study aims to assess the genetic variability and to identify transgressive segregants for grain yield and associated traits in a recombinant inbred line (RIL) population derived from the cross between parents, Jaya and Goa Dhan 2. Analysis of variance revealed significant genetic variability among RILs for all the eight studied quantitative traits. Grain yield exhibited the highest PCV and GCV values (47.83, 44.85%), followed by grains per panicle (28.78, 26.4%) and productive tillers per hill (23.93, 17.65%). In contrast, panicle length (9.35, 8.99%), days to maturity (11.57, 11.32%), and percent fertility (11.22, 7.62%) exhibited relatively lower variation. High heritability combined with substantial genetic advance was observed for days to 50% flowering, days to maturity, plant height, grains per panicle, and grain yield, indicating potential for selection. Grains per panicle (r = 0.327), productive tillers per hill (r = 0.171), and percent fertility (r = 0.165) exhibited significant positive correlations with grain yield. In contrast, days to maturity (r = 0.147) and days to 50% flowering (r = 0.122) showed weaker positive correlations. Conversely, plant height negatively correlated with grain yield (r = − 0.236). The majority of traits exhibited positive skewness, with the number of transgressive segregants ranging from 39 for plant height to 246 for productive tillers per hill. This study revealed significant genetic variability among RILs, with a notable presence of transgressive segregants across the examined traits.