Biology of silkworm reared on Mikania micrantha and Ricinus communis

Among the commercially exploited non-mulberry Silkworm species Eri Silk worm Samia ricini Donovan is the only species domesticated completely and reared all through the year depending upon the availability of the host plant. Castor (Ricinus Communis Linn) is considered to be the major food plant.. According to the information provided by rearers Japanese weed Mikania micrantha kunth ex H.B.K. a widely available weed all over is used by a sizable rearers in Karbi Anglong District of Assam for want of host plants particularly at the latter larval stages. They use to feed the leaves of Mikania micrantha sometimes alone or sometimes along with Castor leaves to the V instar larva with a hope of good quality yarn. But the literature of Mikania micrantha in this regard is totally absent and no earlier investigation was done on it. The present investigations have indicated that foliar constituents have a strong bearing on growth development cocoon production and grainage parameters in eri silkworm thus offer a great scope in feeding of Mikania micrantha a widely available weed all over for rearing the worms for both cocoon and seed production purpose.