BIOLOGY OF RAILY WILD SILKMOTH (LEPIDOPTERA: SATURNIDAE)

A wild ecorace locally known as Raily is distributed in Bastar forest. The main food plant has been found to be Shorea robusta. The famous kosa silk is produced from these cocoons. Seri culturists not able to culture this variety owing to its very Wild nature and little is known about its biology. Hence a study was undertaken on the biology of Raily tasar silk moth of Antheraea my litta Drury in its wild condition. The raily silkworm passes through four distinct phases, viz egg, larva, pupa and moth during its life cycle. The egg is ellipsoidal and bilaterally symmetrical and is about 0.30 + 0.27mm length and 0.250 + 0.33mm in breadth. The average weight of each egg is 0.013 + ().0.073 gm. The newly hatched larve dark brownish in colour and acquired green body colour within 48 hours. The 5" instar measures 10.3 + 0.158 cm and 1.8 + 0.088 cm in length and breadth. The larva exhibits various kinds of body marking, body tubercles, tubercular setae and shining sports. The cocoon weight, shell weight and shell ratio were 13.005 it 1.130g. 2.630 + 0.810 g and 21.13%, respectively. The pupa is adecitious having well defined segmented body. dark brown colour and is spindle shaped. Average developmental period was season specific. Male moth weighed 2.138 + 0.242g and female was 5.973 + 1.610g. Wing span of adult male was 15.838 + 0.378 cm and female 17.333 + 0.418 cm. Single cocoon can produce 1232 meters of reeled yarn. Sustainable conservation measures in Wild can support tasar industry with 50 MT of tasar silk annually.