Determination of Genetic Diversity in Sesame (Sesamum indicum L.)

Abstract

Aim: To assess the degree of genetic divergence (D2 statistics) among sesame genotypes with respect to various traits. Study Design: The present experiment evaluated in the Randomized Block Design (RBD) with three replications. Place and Duration of Study: Experiment was carried out during Rabi, 2023 at Niger Research Station, NAU, Vanarasi. Methodology: To evaluate the genetic diversity among 30 sesame genotypes, Mahalanobis D² Statistics was utilized. The genotypes were classified into six distinct clusters using Tocher’s method, revealing substantial diversity. Results: Cluster I contained the largest 17 genotypes followed by Cluster II with 9 genotypes. Clusters III, IV, V, and VI each included only a single genotype. The highest inter-cluster distance was observed between Cluster I and Cluster IV (25.29) followed by Cluster I and Cluster V (24.07). The lowest inter-cluster distance was 10.00 noted between Cluster IV and Cluster V, suggesting that the genotypes within these clusters are closely related. Cluster III was noted for its high mean values in days to 50% flowering (44.67) and days to maturity (94.33), Cluster IV excelled in capsule width (9.32), Cluster V showed superior traits in plant height (128.78), capsule length (3.23), 1000-seed weight (3.92), harvest index (40.06) and seed yield/plant (9.57), while Cluster VI had the highest values for capsules/plant (39.75) and oil content (46.43). The analysis revealed that the greatest contributions to total divergence were made by 1000 seed weight (51.95%), followed by seed yield per plant (16.32%) and oil content (15.17%). In contrast, plant height and capsule length contributed minimum, each with 0.00%. Conclusion: These results indicate that Clusters III and IV, along with V and VI, exhibit the most significant divergence. This diversity highlights the potential for using these clusters as parent genotypes in breeding programs to achieve a wide range of variability and effective selection.