Abstract
Eri silkworm, Samia ricini (Donovan) is a domesticated multivoltine nonmulberry silkworm and one of the major component of wild (Vanya) silk of India. This insect has been exploited commercially for its silk since time immemorial. Brahmaputra river valley of Assam is considered as original home of cultivated eri silkmoth. There are two species of eri silkworms available in North - East India, viz., the domesticated Samia ricini and its wild progenitor Samia canningi (Hutton). The silk produced by eri silkworm is considered economically the third most important silk in the world after mulberry silk and Chinese Tasar. Northeastern region of India is rich in genetic resources of eri silkworm and numbers of eco-races are existing in nature. Out of 19 species of eri silkworm under genus Samia all over the world, S. ricini (cultivated), S. canningi (wild) and S. fulva (Jordan) are reported to be found exclusively in India. The present paper deals with maintenance of germplasm bank of 26 cultivated eri silkworm eco-races with one wild race of eri silkworm collected from different parts of N.E. India, listing of passport data, morphological characterization, evaluation and development of hybrid with better potentiality. Hybrid worms of wild eri ♀ (S. canningi)× cultivated eri ♂ (S. ricini) reared successfully four consecutive generations. The maximum fecundity (364.6±5.03) and hatching percentage (83 ±2.55) was recorded in F3 generation on Heteropanax fragrans and highest cocoon weight (3.40±0.11), pupal weight (2.98±0.12) and shell weight (0.41±0.02) were recorded in F2 generation on Heteropanax fragrans.
