POLYAMINE SUPPLEMENTS TO THE DIET ENHANCE LARVAL AND SILK GLAND CHARACTERISTICS IN TASAR SILKWORM Antheraea mylitta D

Polyamines (PAs) are polycationic, biosynthetic intermediate metabolites of amino acids and regulate many metabolic processes inside cells i.e., organization of DNA, RNA, transcription and translation etc., which contribute to promoting growth and development in animals. The DABA bivoltine (2 crops/year) ecorace of Tasar silkworm, Antheraea mylitta is reared by tribal populations in Indian forest ecosystems mainly for livelihood. Due to its rearing in natural wild conditions, the abiotic and biotic environmental stress led to 60-70% crop loss in every rearing. Silk yarn is used in textile industries while raw and fabricated products possess export value. Recent investigations revealed that silk proteins viz., fibroin and Sericin tend to have high potential biomaterial for tissue engineering. Hence, there is a need to select high-yielding and disease-resistant varieties for sustainable crop improvement. As silk production relies on the fifth instar larval and silk gland development, which in turn is determined by quality food intake and molecular mechanism contributed by nutritive supplements, the present work is taken up which was not explored to date. The fifth instar larvae of A. mylitta D (Daba TV) were allowed to feed on the Terminalia arjuna leaves treated with polyamines (Spermidine, Spermine and Putrescine) in 50 µM, 100 µM and 150 µMconcentrations. The larval behaviour was studied; larval characteristics, silk gland development, silkworm Body Mass Index (BMI), mortality and Effective Rearing Rate (ERR) were estimated statistically and interpreted. The study revealed significant enhancement in larval, silk gland weight and disease resistance in certain specified concentrations of PAs.