3种农药对北方毛胸材小蠹成虫毒力及酶活性的影响OA

To investigate the toxicity of thiamethoxam,nitenpyram,and flonicamid against adults of Anis-andrus dispar and their effects on the activities of detoxifying enzymes and protective enzymes,the indoor tox-icity of 3 pesticides against A.dispar was determined using the immersion method.Adults were treated with sub-lethal concentrations(LC50),and dynamic changes in the activities of glutathione S-transferase(GST),carboxylesterase(CarE),multifunctional oxidase(MFO),superoxide dismutase(SOD),peroxidase(POD),and catalase(CAT)were analyzed.The results showed that thiamethoxam had the best lethal effect(72 h LC50=2.638 mg/L),followed by nitenpyram(72 h LC50=24.769 mg/L),and flonicamid was the worst(72 h LC50=486.482 mg/L).Among the detoxification enzymes,thiamethoxam and nitenpyram significantly induced stepwise increases in GST and CarE activities but inhibited MFO activity.Flonicamid continued to inhibit GST and MFO activities and initially increased CarE activity,then decreased it.Among the protective enzymes,thia-methoxam significantly increased POD and CAT activities,whereas flonicamid exhibited a phase-dependent in-hibitory effect on SOD and CAT activities.