Seasonal variation in the commercial and economic characters of Eri Silkworm, Samia ricini (Donovan)

Abstract :

Eri culture is mostly confined to the Brahmaputra valley of Assam and in few districts of the neighbouring states mainly Meghalaya, Nagaland, Manipur and Arunachal Pradesh. Eri culture is also spreading in different non-traditional states like, Andhra Pradesh, Tamil Nadu, Karnataka, Gujarat, Jharkhand, Chhattishgarh etc. The eri silkworm, Samia ricini (Donovan) is multivoltine and polyphagous in nature feeding on a number of food plants namely castor, Ricinus communis, Kesseru, Heteropanax fragrans, Tapioca, Manihot utilissima, Payam, Evodia flaxinifolia and Barpat, Ailanthus grandis and several others. Eri silkworm is reared indoor conditions for production of cocoons. Though eri silkworm can be reared throughout the year still there is a variation in some commercial characters in different seasons. To observe its seasonal variations in commercial characters a study was undertaken using a promising eri silkworm, Borduar eco-race feeding with castor. The highest larval weight (7.32 g), average fecundity (580 Nos.) and ERR (94.7%) was recorded during October-November. The highest single cocoon weight (4.01 g) was observed during August-September. Hence, it has been illustrated that autumn is the best season for eri silkworm rearing to improve productivity of eri silk

Keyword :

Eri silkworm, season, cocoon character

Author(s) : Sarmah, M. C., Ahmed, S. A., Sarkar, B. N., Debaraj, Y., Singh, L. S.
Downloads : 2136
Published Issue : 2012 Vol. 7 Number 2

2012 Vol. 7 Number 2