Abstract: 【Aim】 This study aims to study the effects of cyromazine on the growth and development of the black soldier fly (Hermetia illucens) larvae in chicken manure and the detoxification of cyromazine by the added activated carbon. 【Methods】 The 3rd, 4th and 
5th instar larvae of H. illucens were reared in the chicken manure containing different concentrations (0, 0.1, 0.25, 0.5, 1, 2.5, 5, 10 and 15 mg/kg) of cyromazine, and the changes in the growth and development (body weight and mortality) of the larvae were measured. Reared in the chicken manure added with activated carbon at different concentrations (0, 10, 30, 50, 100, and 150 g/kg), the effects of activated carbon on the growth and development of the 3rd instar larvae of H. illucens and its detoxification 
effect on cyromazine were assayed. 【Results】 Reared in the chicken manure containing certain concentration of cyromazine, the 3rd, 4th and 5th instar larvae of H. illucens showed such symptoms as elongation of somites, cessation of feeding and even death. The medium lethal concentration (LC₅₀) values of cyromazine to the 3rd, 4th and 5th instar larvae of H. illucens were 0.18, 1.39 and 6.45 mg/kg, respectively. Activated carbon at the concentrations of 30-100 g/kg in chicken manure significantly promoted the growth and development of the 3rd instar larvae of H. illucens and detoxified the toxicity of cyromazine to the 3rd instar larvae with the 95% effective dose (ED₉₅) value of 51.83 g/kg. 【Conclusion】 The sensitivity of H. illucens larvae to cyromazine in chicken manure gradually decreases with larval instar. Activated carbon can be used to detoxify the toxicity of cyromazine in chicken manure to H. illucens larvae, providing a solution for application of H. illucens to process chicken manure containing cyromazine.

Key words: Hermetia illucens, cyromazine, activated carbon, chicken manure, detoxification