Bioactive phytojuvenoid compounds influence protein contents in the larvae and pupae of Bombyx mori (Lepidoptera: Bombycidae)

Abstract

This study reports, the effect of bioactive phytojuvenoid compounds on the level of total protein contents in the silk gland, fat body and haemolymph of fifth instar larvae and fat body and haemolymph of pupae of multivoltine mulberry silkworm (Bombyx mori). The bioactive phytojuvenoid compounds were derived after soxhlet extraction from the leaves of the Azadirachta indica and needles of Pinus longifolia were used in 5%, 15%, 25% and 35% concentrations for single, double and triple treatment of third, fourth and fifth instars larvae of B. mori. Further rearing was performed at normal rearing conditions with control set of study. The level of total protein contents increased in the silk gland, fat body and haemolymph of fifth instar larvae and fat body and haemolymph of pupae with increase in concentrations of phytojuvenoid from 5 to 25% in case of single, double and triple treated larvae whereas, in 35% concentration, the level of total protein contents was increased slightly in case of single treated larvae and further gradually decreased for the double and triple treated larvae. Maximum level of total protein contents in the silk gland of fifth instar larvae (60.248 ± 2.142 μg/mg tissue), haemolymph of fifth instar larvae (78.124 ± 3.002 μg/ml tissue) and pupae (71.146 ± 3.245 μg/ml tissue) and fat body of fifth instar larvae (68.124 ± 3.002 μg/mg tissue) and pupae (66.146 ± 2.245 μg/mg tissue) were recorded in case of larvae triple treated with 25% concentration of phytojuvenoid derived from Pinus longifolia, while control study revealed minimum values. Thus, triple treatment of larvae with 25% concentration of phytojuvenoid derived from P. longifolia is most suitable to enhance the level of total protein contents in the tissues of B. mori. This study is important from academic as well as economic point of view and will further help to explore a new concept in this field.