Biology of Antheraea frithi Moore (Lepidoptera: Saturniidae) on Sal (Shorea robusta) in South Kamrup District of Assam

Antheraea frithi Moore is a wild temperate tassar silk moth found abundantly in the North Eastern region of India. They primarily feed on Oak (Lithocarpus dealbata), but some wild isolated populations of this species found in the South Kamrup region of Assam have been reported to feed on Sal (Shorea robusta) and Melastoma malabathricum. The present investigation has been designed with a view to study the biology of Antheraea frithi on Shorea robusta. Various evaluation descriptors and seasonal study have revealed the influence of season, host plants and rearing conditions on the viability and other growth parameters. Growth parameters like larval weight, cocoon weight, shell weight, etc. varied from season to season with Autumn season showing the highest productivity followed by Summer and Spring. A visible few cocoons also showed a diapausal activity during the winters. Differences in larval size were also observed in different larval stages in different seasons. Average fifth instar larvae had a length of 7.04 0.04 cm and weight 9.634 0.30 g in Autumn season followed by Summer and Spring.