Evaluation of the toxic effects and midgut biological changes induced by low concentrations of cyantraniliprole in Bombyx mori.

Abstract

Cyantraniliprole (Cya), a diamide insecticide, is widely utilised for the management of Lepidoptera pests owing to its potent insecticidal efficacy and broad spectrum of activity. The extensive use and prolonged environmental persistence of this insecticide pose a significant threat to the sustainable development of sericulture. This study firstly assessed the lethal toxicity of cyantraniliprole to the 5th instar larvae of Bombyx mori. Exposure to cyantraniliprole (LC₅, LC₁₀ and LC₂₀) resulted in a concentration-dependent reduction in larval weight, pupal weight and survival rate and a prolongation of larval development time. Moreover, cyantraniliprole LC₁₀ resulted in substantial structural damage to the epithelial cells, suppressed the mRNA levels of oxidative phosphorylation genes, perturbed ATP synthesis and led to an imbalance of intracellular reactive oxygen species. Meanwhile, the starvation treatment suggested that the impacts of cyantraniliprole on silkworms cannot be solely ascribed to nutritional deficiencies. Additionally, the results revealed that cytochrome P450s might serve as a pivotal factor in the detoxification metabolism of cyantraniliprole in the midgut of silkworms. The findings of this study offer evidence for the ecological risk posed by environmental residues of cyantraniliprole to non-target organisms and are also of great significance for sericulture production.