Multigenerational sulfoxaflor selection induces tolerance but reduces fitness and predatory performance in the biological control agent Coccinella septempunctata

BACKGROUND Assessing the long‐term compatibility of insecticides with biological control agents is essential for sustainable integrated pest management (IPM). While the acute toxicity of sulfoxaflor to beneficial arthropods has been widely studied, its multigenerational effects on predator fitness and biological control performance remain poorly understood. Here, we investigated the consequences of continuous sublethal sulfoxaflor selection on the predatory ladybird Coccinella septempunctata over eight successive generations. We combined toxicity bioassays, age‐stage two‐sex life table analyses, functional response assays, detoxification enzyme measurements, and transcriptomic profiling to evaluate adaptive responses and associated ecological costs. RESULTS Continuous selection increased sulfoxaflor tolerance by 8.5‐fold, indicating that C. septempunctata can respond to prolonged insecticide pressure. However, this response was accompanied by significant fitness costs, including prolonged pre‐oviposition periods, reduced longevity, shortened oviposition period, lower egg hatchability, and a reduced net reproductive rate. Predatory capacity was also affected, with the selected strain exhibiting longer prey‐handling times and reduced prey consumption at high aphid densities, suggesting a diminished ability to suppress pest outbreaks under favorable prey conditions. Generation‐dependent increased activities of cytochrome P450 monooxygenases, glutathione S‐transferases, and carboxylesterases were associated with the selection process. Transcriptomic analyses revealed widespread changes in genes and pathways related to detoxification, metabolism, development, and physiological regulation. CONCLUSION Our results demonstrate that adaptation to chronic sulfoxaflor exposure in C. septempunctata is associated with demographic and ecological trade‐offs. These findings highlight the importance of incorporating multigenerational and sublethal endpoints into pesticide risk assessment and compatibility evaluations within IPM programs.