Influence of Bakuchiol, a JH analogue from Bemchi (Psoralea corylifolia) on Silk Production in Silkworm, Bombyx mori L. (Bombycidae: Lepidoptera)

The influence of a juvenile hormone analogue (JHA), bakuchiol on the silk yield of silkworm, Bombyx mori L. was studied involving two popular commercial hybrids, KA x NB4D2 (bivoltine x bivoltine) and PM x NB4D2 (multivoltine x bivoltine). The compound was administered topically to 5th instars at 24, 48, 72 and 96 h as a single dose. Three-concentration viz., 0.625, 1.25 and 2.5 ppm were tested. Economic characters of the larvae and the resultant cocoon traits were measured. The result showed that 1.25 ppm of bakuchiol applied to 48 h old 5th instars was the most favourable treatment for improvement of commercial traits. Cocoon and cocoon shell weight and filament length have increased significantly due to this treatment. The possible role of exogenous JH analogues in eliciting this response in silkworm is discussed @ JASE