Zwittermicin A对Cry1Ac杀虫活性的增效作用  

Zwittermicin A Enhances the Toxicity of Bt Cry1Ac to Spodoptera exigua Hübner

作　　者：李晶[1] 刘建密[1] 郭巍[1] 张霞[1] 申建茹[1] 

机构地区：[1]河北农业大学河北省农作物病虫害生物防治工程技术中心,河北保定071001

出　　处：《华北农学报》2008年第5期136-141,共6页Acta Agriculturae Boreali-Sinica

基　　金：国家"973"计划项目(2003CB114201);河北农业大学引进人才启动项目

摘　　要：Zwittermicin A(ZwA)能够增加苏云金杆菌(Bacillus thuringienesis,Bt)Cry1Ac蛋白的杀虫活性。生物测定使用生长在人工饲料上的甜菜夜蛾幼虫。用Cry1Ac蛋白单独处理甜菜夜蛾初孵幼虫,体重抑制活性明显,杀虫活性较低;单独用ZwA处理时无杀虫活性。当ZwA浓度为0.1 mg/mL、Cry1Ac浓度为1 mg/mL时,48 h校正死亡率达90%。对甜菜夜蛾5龄幼虫进行生物测定,当用25μg ZwA和5μg Cry1Ac分别饲喂试虫时,无杀虫活性;用25μg ZwA和5μgCry1Ac同时饲喂试虫时,84 h试虫全部死亡。对甜菜夜蛾5龄幼虫中肠组织切片分析发现,口服25μg ZwA和5μgCry1Ac的幼虫12 h,中肠变细小,中肠壁变厚,围食膜无法正常形成;36 h后中肠壁逐渐恢复正常,围食膜重新形成。Zwittermicin A （ZwA）enhanced the insecticidal activity of Bacillus thuringienesis （Bt） Cry1Ac protein. The mortality was 90% at 48 h after S. exigua larvae were treated with Cry1Ac in the presence of ZwA,which was higher than that without ZwA.All the 5th-instar larvae were dead at 84 h after fed with 5 μg of Cry1Ac plus 25 μg of ZwA（per larvae）. Microscopical observation of dissected midgut showed that at 12 h post feeding with Cry1Ac and ZwA no PM were present in the treated larvae, in contrast to the presence of a fully formed PM in the midgut of control larvae. But ＇after 36 h, the midgut displayed normal and PM formed again.

关 键 词：ZwittermicinA CRY1AC 生物活性测定 中肠 围食膜 

分 类 号：S476.1[农业科学—农业昆虫与害虫防治]