Variability, heritability and genetic divergence in rice genotypes under saline condition

Rice is staple food for Asian people and there is urgent need to produce more rice per unit area, which can be enhanced by possibly utilizing the unexplored germplasm for adverse climatic and soil conditions. Among the stress, salinity is profound and gaining prime importance in upcoming years; only possible way is breeding for salt tolerance by utilizing available genetic resources. Sixty genotypes of rice were evaluated under natural saline conditions during 2013-2014 for eleven characters viz., days to first flower, plant height, number of tillers plant-1, number of panicles plant-1, panicle length, number of grains panicle-1, thousand grain weight, grain length, grain breadth, grain L/B ratio and grain yield plant-1. The analysis of variance revealed the presence of significant differences among all the genotypes studied. Heritability in broad sense was observed high for all the characters studied except number of tillers per plant. Except number of tillers per plant, panicle length and grain breadth, for all other traits were having high genetic advance as per cent of mean coupled with high heritability. The genetic divergence among the genotypes was estimated through Mahalanobis D2 statistics. The sixty genotypes were grouped into 6 clusters. Grain yield plant-1 (22.14 %) contributed maximum towards total genetic divergence followed by number of grains panicle-1 (17.34%) and plant height (16.44 %).