Studies on mechanisms of insecticide resistance and the application of characteristics of insecticide resistance for the integrated pest management

1阐明抗药性产生的机制。乙酰胆碱酯酶对杀虫剂的敏感性降低，这是最重要的抗性因素之一。克隆了不同害虫的乙酰胆碱酯酶(AChE)基因，并对其氨基酸序列进行了分析.结果表明，抗药性不仅是由点突变引起的，而且是由后翻译引起的.通过测定AChE对杀虫剂的敏感性，筛选出与抗药性负相关的杀虫剂组合.在抗性家蝇中，雄性的谷胱甘肽-S-转移酶活性高于雌性。雄性发芽因子位于第2号染色体上，雄性的高GST活性是由于GST基因的扩增所致。结果1.对甜菜夜蛾细胞色素P450基因(CYP9A)进行了分析。根据抗药性昆虫的特点建立害虫综合治理体系。发展简便的抗药性监测方法是制定抗药性策略的重要内容之一。通过对稻纵卷叶蝉、家蝇、稻水象甲等与抗药性有关的昆虫个体的酯酶、乙酰胆碱酯酶、谷胱甘肽转移酶等酶活性的测定，发现了与抗药性有关的单虫。在不能应用生化监测方法的情况下，开发了简单的生物测定方法来防治小菜蛾、西花蓟马等，引入了与交叉抗药性呈负相关的杀虫剂组合，抗药性天敌，用选择性杀虫剂保护天敌，核多角体病毒等。也能有效地减轻杀虫剂的选择压力，并有助于延缓或延缓抗药性的发展。

1 Clarification of mechanisms of insecticide resistance. Reduced sensitivity of AChE to insecticides which is one of the most important resistance factor. AChE cDNA are cloned and their aminoacids sequences were clarified in various insect pests such as Nephotetix cincticeps, Cidex tntaeniomychus, etc. Results indicated that insecticide resistance was caxised not only by the point mutation but also by the post translation By assaying AChE sensitivity to insecticides, combination of insecticides which show negatively con-elated cross resistance were screened. In OP resistant house fly, glutahtion-S-transferase activity is higher in males than in females the male germinating factor is located on the 2^<nd> chromosome, high GST activity in males were caused by ihe amplification of GST gene. Cytochrome P450 gene (CYP9A) which is responsible for permethnn resistance in Spodptera exigua was analyzed.2. Establishment of the integrated pest management based oncharacteristics of insecticide resistant insects. Development of simple monitoring methods for insecticide resistance is one of the most important points for us establish a strategy for insecticide resistance. By assaying enzyme activities (esterase, AChE, GST) of individual insecte which an involved in insecticide resistance were developed (green rice leaf- and plant hoppers, house fly, rice water weevil, etc.). In case we could not apply biochemical monitoring methods, simple bioassay methods were developed against diamondback moth, western flower thrips, etc. Introduction of combination of insecticides which show negatively con-elated cross resistance, insecticide resistant natural enemies, conservation of natural enemies with selective insecticides, nucleopolyhedrovirus, ete. were also effective to reduce the selection pressure by insecticides and can contribute to delay or retard the development of insecticide resistance.