Research on the metabolic detoxification of trace chlorantraniliprole in Bombyx mori (Lepidoptera: Bombycidae) fed with artificial diet based on nutritional compensation

Abstract

Bombyx mori (Lepidoptera: Bombycidae) is an oligophagous lepidoptera insect that primarily feeds on mulberry leaves. The feeding performance of “artificial feed rearing of young silkworm combined with mulberry leaves rearing of grown silkworm” was significantly higher than that of silkworms reared on artificial diets across all instars. Following prolonged indoor domestication, B. mori exhibits heightened sensitivity to chemical pesticides. To investigate the metabolic detoxification response characteristics during nutritional compensation, mulberry leaves were treated with trace chlorantraniliprole (0.01 mg/L) for the 5^th instar larvae, which had been reared on artificial diet during the 1^st - 4^th instars. Upon transitioning from artificial diet to mulberry leaves, the growth rate was significantly increased, reaching 147.49 % within 24 h. Additionally, the activities of protease and lipase in digestive fluid were markedly enhanced. The triglyceride content increased by 18.15 % in hemolymph and by 27.26 % in the fat body at 72 h. Conversely, the levels of free amino acids in hemolymph and trehalose in the fat body significantly decreased. At 24 h, the expression levels of PI3K, AKT, and INR were up-regulated 3.682, 3.160, and 6.027 folds, as well as CYP4M5, CYP6AB4, GSTe3, and CarE2 were up-regulated 3.972, 2.816, 3.890, and 2.660 folds at 120 h, respectively. With trace chlorantraniliprole treatment, the upregulation of growth genes was prioritized. In contrast, the upregulation of detoxification genes was delayed, demonstrating a consistent trend in detoxification enzyme activity following gene expression. This study provides a momentous reference for elucidating the interaction between nutritional and detoxification metabolism in B. mori.