Non-steroidal ecdysone agonists: new tools for IPM and insect resistance management

The non-steroidal, bis-acylhydrazine agonists of the insect molting hormone, 20-hydroxyecdysone, were first discovered over ten years ago. An extensive structure–activity optimization program yielded one commercial insecticide, tebufenozide (RH-5992) and two additional candidate insecticides (methoxyfenozide and halofenozide) which are in development. Tebufenozide is highly selective for lepidopteran pest control and is thus useful for IPM and resistance management programs. Methoxyfenozide (RH-2485) is also lepidopteran-selective but significantly more potent than tebufenozide and offers control of a wider range of lepidopteran pests. Halofenozide (RH-0345) is generally less potent and selective than tebufenozide or methoxyfenozide. However, its physical and biological properties make it well suited for control of beetle grubs and caterpillars in the soil. Target pest selectivity, new and novel mode of action, ecotoxicological safety and safety to beneficial arthropods make these insecticides valuable tools for integrated pest and resistance management programs.