Comparative Assessment of Oral Insecticide Toxicity in the Indian Honey Bee and a Stingless Bee

Pollinators, particularly honeybees are essential for agricultural productivity and ecological balance. However, the indiscriminate use of insecticides poses a significant threat to these vital species. This study evaluated the oral toxicity of commonly used insecticides, including neonicotinoids, pyrethroids and organophosphates, on two important pollinators, Apis cerana indica and Tetragonula iridipennis. Test insects were orally exposed to varying concentrations of thiamethoxam, carbosulfan, lambda-cyhalothrin, imidacloprid, profenofos, and chlorpyrifos through oral application. Mortality, behavioral changes, and physiological effects were recorded at 24 hours after treatment (HAT). All tested insecticides exhibited extreme toxicity, resulting in 80–100% mortality in both bee species within 24 HAT. In contrast, buprofezin, an insect growth regulator, exhibited significantly lower mortality, causing 25.28% mortality in A. cerana indica and 21.48% in T. iridipennis at 24 HAT. These findings underscore the urgent need to consider species-specific sensitivity when formulating pesticide regulations and promoting bee-safe agricultural practices. Integrated pest management (IPM) and the development of pollinator-friendly alternatives are essential for safeguarding pollinator populations and ensuring sustainable agriculture.