Abstract
Day to day changes in lipids and lipase activity were examined in the haemolymph of 5th instar silkworm Bombyx mori L during the progress of fungal pathogen Beauveria bassiana. The increased trend of lipid content was observed in haemolymph of control (31.44 mg/ml to 34.8 mg/ml), in contrast decreased trend of lipid content was noticed in experimental larvae (31.06 mg/ml to 27.39 mg/ml). In case of lipase activity, increased trend of lipase activity was observed in haemolymph of both inoculated (0.137 to 0.186 µ moles/ml) and control (0.137 to 0.178 µ moles/ml) up to the 5th day, then the enzyme activity was decreased on the 6th day of the 5th instar in treated (0.179 µ moles/ml) and control (0.169 µ moles/ml). Compared to control in inoculated lipase activity was increased. Depleted lipid content associated with an enhanced lipase activity during the progress of fungal pathogen infection. The patho-physiological studies of economically important insects such as silkworm during the progress of fungal pathogen will help to design diagnostic tools to control the disease in turn to enhance the quality parameters of cocoon crops.
