Evaluation of Triflumuron, a benzoylphenylurea derivative, on Tenebrio molitor pupae (Col., Tenebrionidae): effects on cuticle.

Triflumuron (TFM), a benzoylphenylurea (BPU) derivative, exhibited insecticidal activity when injected to newly ecdysed pupae of Tenebrio molitor. Mortality occurs by defect in adult ecdysis. Treatment resulted in a significant increase in the duration of pupal stage and caused a reduction in both cuticle thickness and incorporation of ¹⁴C-labelled precursor into chitin compared to controls. Moreover, TFM reduced the amount of cuticle chitin without any significant effect on protein level. Thus, TFM acts by preventing the chitin biosynthesis confirming the primary mode of action of the BPU insecticides. [ABSTRACT FROM AUTHOR]