Mechanism of adult emergence in Xanthopimpla pedator (Fabricius)- a major pupal parasitoid of Tasar silkworm

Abstract

Aim: The study was conducted to elucidate the mechanism involved in adult emergence behavior of Xanthopimpla pedator a pupal parasitoid of tasar silkworm. Methodology: Behavioral observations were made to study the mechanical approaches used during emergence and SDS-PAGE analysis was carried to know the possibility of proteases in the digestive secretions. Results: The findings of the study suggest that X. pedator uses physical and chemical to achieve safe passage from the host pupae and cocoons. It was observed that during the process of emergence, X. pedator breaks host pupae by means of mandibular action (by biting the pupal shell). Further, it was noticed that to make emergence hole on host cocoon X. pedator found to employ digestive secretion to soften and disintegrate the silken shell, besides it also deploys mandibles to spread out the secretion on intended place of exit hole. SDS-PAGE analysis showed the presence of series of enzymes, possibly involved in cocoon softening. Interpretation: Findings of this study forms the basis that X. pedator, a major pupal parasitoid of tasar silkworm, uses both physical and chemical approaches to achieve safe passage from the host pupae and protective silken cocoon. Key words: Digestive secretion, Mandibular action, Parasitization, Xanthopimpla pedator