Impact of feeding different mulberry varieties during chawki rearing on commercial characteristics of silkworm, Bombyx mori L.

Silkworm (Bombyx mori L.) being a monophagous insect feeds solely on mulberry leaves (Morus spp.).The insect undergoes five instars during its larval phase with four moults and its rearing is divided into two stages: chawki rearing (rearing of first two instars) and late-age rearing (rearing of subsequent three instars). Among many interlinked factors that decide the success of silkworm rearing, young age silkworm rearing (chawki rearing) technique is the most important one and has the closest bearing on the stabilization of cocoon crop as well as on productivity. The contribution of chawki rearing technology to the remarkable increase in the cocoon productivity cannot be neglected as more than 80 per cent of silkworm rearing, especially in Southern India depends on chawki reared worms. Since mulberry leaf is the only source of nourishment to silkworms, its quality plays an important role in improving the growth and development of the silkworm. In order to assess the performance of mulberry genotypes aimed at selection of superior varieties for rearing performance, a study was conducted to evaluate five different mulberry varieties viz., Ichinose, KNG, Goshoerami, Koksu-21 and Tr-10 when fed during chawki rearing on the commercial characteristics of silkworm. The study revealed that KNG outperformed other varieties in terms of enhancing silkworm growth and productivity with better mature larval weight (37.41g), shorter total larval duration (689hrs), cocoon yield per 10,000 larvae by number (9405) and weight (15.30kg), single cocoon weight (1.65g), shell weight (0.34g) and shell percentage (20.61).