Assessment of Genetic Diversity in Sesame (Sesamum indicum L.) Based on Agro-Morphological Traits

Abstract

Genetic divergence among parents is of paramount importance in selecting them for hybridization programme for crop improvement. Genetic divergence was assessed among 30 sesame genotypes which were evaluated in RBD with an objective to classify and understand the nature and magnitude of genetic diversity with regard to grain yield, yield components and quality traits using Mahalanobis D2 statistics. The genotypes differed significantly regarding the characters studied and displayed marked divergence and were grouped into four clusters following Tocher’s method. Cluster I had twenty-seven genotypes while the Cluster II, cluster III and cluster IV were monogenotypic comprised only one genotype each. The oil content exhibited maximum contribution towards divergence. The  maximum inter  cluster  distance  was  recorded  between  cluster  III  and  IV (2717.76) followed by cluster I and IV (1760.59), cluster II and III (991.96), cluster I and II (695.67), cluster I and III (637.32) and cluster II and IV (584.59) indicating the chances of getting high yielding recombinants would be better if the crosses are made among the genotypes of these groups under timely sown condition. The genotypes in cluster III and cluster IV, due to maximum inter cluster distance between them, exhibited high degree of genetic diversity and thus may be utilized under inter varietal hybridization programme (transgressive breeding) for getting high yielding recombinants. The analysis of divergence indicated significant differences among parental lines for all the agro-morphological characters. Based on results obtained in the present investigation, it is concluded that the allelic diversity can be used for future breeding program. The traits under study are largely associated with each other and should be taken into consideration either simultaneously or alone for selecting a high yielding sesame genotype.