Genetic diversity, correlation and path co-efficient for yield and yield associated traits in rice (Oryza sativa)

The present investigation was conducted to assess the high grain yielding varieties and their related traits for evolving better genotypes for further breeding programme. Twenty-five rice genotypes were collected from different geographical regions of Tamil Nadu to discern the extent of divergence, variability and character association. The analysis of variance exposed the presence of significant differences among all the genotypes for eight characters studied and indicated the occurrence of considerable amount of deviation in the genotypes. In D2 analysis, 25 rice genotypes were grouped into six clusters. The maximum intra-cluster distance was registered in cluster III (31.88). The maximum inter-cluster distance was found between cluster II and cluster IV (144.96). IR 64, PMK 3 and CO 51 were the potential donors and could be used as a parent as they possessed high per se for yield and majority of its attributes. Number of grains/panicle, 1000-grain weight, plant height, days to 50% flowering and grain yield/plant were the major contributors towards the total genetic divergence among the traits studied. The genetic correlation revealed that number of tillers/plant and panicle length showed positive and significant association with respect to number of productive tillers/plant and number of grains/panicle at both genotypic and phenotypic levels. So, it may be inferred that selection and manoeuvring of anyone of the traits viz., number of productive tillers/plant and panicle length were likely to improve grain yield/plant. Path analysis indicated that number of productive tillers/plant, 1000-grain weight and number of grains/panicle exerted maximum positive direct and all identified genotypes with their resulted traits would be obliging to progress or deploy for further breeding programme.