An analysis of genetic variation and divergence in Indian tropical polyvoltine silkworm (Bombyx mori L.) genotypes


Central Sericultural Germplasm Resources Centre, Central Silk Board, Hosur 635 109, Tamil Nadu, India


The genetic variation and diversity among fifty-eight polyvoltine silkworm genotypes was estimated by using ten economic traits. The results revealed that the single shell weight showed higher genetic variation such as PCV% (17.20%), GCV% (12.93%), and heritability (56.5%) followed by single cocoon weight, shell ratio and matured larval weight. The D2 (Mahalonobis? distance) statistics revealed nine clusters with substantial inter and intra cluster distances. The genotypes included in different clusters varied from 1 to 16. The genotype Pure Mysore was included in isolated cluster indicates its longer adaptation. The genotypes included in cluster VIII and IX showed optimum genetic distance along with higher cluster mean emphasised for utilization in the silkworm breeding.