Sublethal effects of flufenoxuron on Spodoptera mauritia Bosid. (Lepidoptera: Noctuidae) testicular biochemical...

Flufenoxuron, a widely used chitin synthesis inhibitor, is effective against several insect and mite pests. This study evaluated the reproductive toxicity in male sixth-instar larvae of Spodoptera mauritia, a sporadic lepidopteran pest of rice crops. Larvae were topically treated with sublethal concentrations of flufenoxuron (ED₂₅-0.00068 μg and ED₅₀-0.00015 μg), and biochemical responses were assessed at 48, 96, and 144 h post-treatment. Significant reductions in lipid, protein, and carbohydrate levels were observed in the haemolymph and testes of treated larvae, indicating a potential impairment of reproductive physiology. The electrophoretic profiling showed significant alterations in testicular and haemolymph proteins, particularly in the range of 65 kDa to 79 kDa and 61 kDa to 77 kDa, respectively. Histopathological analysis of the testes revealed spermatogenesis disruptions, including germ and somatic cell alterations. Flufenoxuron affected the organization, distribution, and development of male germ cell cysts, particularly during spermiogenesis. These findings highlight flufenoxuron's toxicity in S. mauritia male reproductive development and provide a basis for further studies on its reproductive effects in other insect species.