Genetic diversity and principal component analysis in cultivated rice (Oryza sativa) varieties of Assam

Abstract

Rice (Oryza sativa L.) is the pre-eminent cereal crop of Assam in term of production and cultivable area. The measurement of genetic diversity is crucial to pick up the appropriate genotypes in a crop improvement programme. Identification of traits contributing towards genetic diversity in a given population can help in formulating effective selection criteria. This study was carried out in 64 indigenous rice genotypes collected from North Bank Plains and Upper Brahmaputra valley zones of Assam during rainy (kharif) seasons of 2021 and 2022. Based on the yield attributing characters, the cultivars were categorized into 8 clusters. Cluster evaluation showed that cluster II and V had farthest distance from cluster V (431.18), followed by cluster I and II (377.62). The study on the Principal component analysis showed the traits, days to 50% flowering (DF), days to maturity (DM), filled grains per panicle (FG), biological yield (BY) and harvest index (HI) had maximum contribution towards the total variability. The genotypes from the diverse clusters having desirable per se performance could be selected for inclusion as parents in hybridization programme. Identification of component traits through the principal component analysis will help in formulating efficient selection criteria for further genetic improvement of rice.