烟田常用杀虫剂对烟蚜茧蜂的毒力及其保护酶的影响

为了筛选对烟蚜茧蜂安全性高的药剂并明确烟田常用杀虫剂对烟蚜茧蜂保护酶的影响,测定了3种烟田常用杀虫剂对烟蚜茧蜂成虫的毒力以及不同浓度的吡虫啉对烟蚜茧蜂成虫体内超氧化物歧化酶、过氧化物酶和过氧化氢酶活性的影响。结果表明,杀虫剂对烟蚜茧蜂成虫的毒力大小顺序为:啶虫脒 > 高效氯氟氰菊酯 > 吡虫啉;从不同浓度的吡虫啉对烟蚜茧蜂生命活动和防御机制的影响来看,除LC₁₀浓度吡虫啉促进烟蚜茧蜂成虫体内POD活性提高和3个浓度处理后12 h成虫CAT活性显著提高外,其余处理浓度和时间对3种酶的活性呈现抑制作用。此结果为探明烟蚜茧蜂对杀虫剂的防御机制提供了一定的理论依据。

Effects of Conventional Insecticides on Aphidius Gifuensis Ashmead and Its Protective Enzymes in Tobacco Fields

In order to screen for safer insecticides to Aphidius gifuensis Ashmead and know about the effects of conventional insecticides on protective enzymes of Aphidius gifuensis Ashmead in tobacco fields, toxicity of three conventional insecticides to Aphidius gifuensis Ashmead was determined via the residual film method. Effects of different concentrations of imidacloprid on SOD, POD and CAT activities of Aphidius gifuensis Ashmead was also determined. The results showed that the order from high toxicity to low toxicity was: acetamiprid >lambda-cyhalothrin >imidacloprid. In terms of the effects of different concentrations of imidacloprid on the life activities of Aphidius gifuensis Ashmead and their defense mechanisms, all the treatments showed inhibition on enzyme activities except that the LC₁₀ concentration of imidacloprid improved POD activities in adults and CAT activities increased significantly in adults after 12h treatment of three concentrations. This result provides theory basis for understanding the defense mechanisms of Aphidius gifuensis Ashmead against insecticides.