Abstract

The nature and magnitude of genetic divergence and character association were estimated in identified 225 core rice germplasm accessions (landraces) received from National Bureau of Plant Genetic Resources (NBPGR), New Delhi. A total of 11 quantitative traits were measured at suitable stage of rice germplasm. Core rice germplasm accessions were grouped into 15 clusters. The utmost inter-cluster distance varied from 6.654 to 1.810. The highest inter-cluster distance was observed between clusters XIII and VIII (6.653) suggesting maximum variability among them. Cluster I (3.51) showed highest mean value for 100-seed weight. Cluster XV had highest mean value for panicle length (28.65), effective tillers/plant (7.06) and L/B ratio of 3.32. The better genotype can be selected for most of the characters on the basis of mean performance in the clusters. The cluster XV showed highest grain yield/plant and effective tillers/plant (9 tillers/plant). This indicated that these clusters could be utilized in the hybridization programme for obtaining desirable transgressive segregants. The correlation coefficient of grain yield had positive and significant (P<0.01) correlation with leaf length (r=0.3443), days to 50% flowering (r=0.557), plant height (r=0.666), panicle length (r=0.3120), number of effective tillers/plant (r=0.3377), plant height (r=0.666) and panicle length (r=0.3120), had positive and significant (P<0.01) correlation with leaf width (r=0.2581), leaf length (r=0.4805), days to 50% flowering and plant height, while leaf width had positive (P=0.05) correlation with plant height. The hybridization regarding genotypes belonged to these clusters and correlation was expected to give desirable segregants in rice breeding programmes. On the basis of yield and by considering all desirable traits, germplasm accessions were identified viz., IC 460174X, IC 460313X, IC 460308, IC 860289, IC 115710, IC 1333418, IC 133376, IC 134515 and IC 124377.