二化螟对3种杀虫剂的抗性测定及增效作用研究

采用4龄幼虫点滴法测定了江苏省不同地区二化螟种群对杀虫单、甲胺磷和三唑磷的抗性水平，并以浙江慈溪种群为对象，进行了活体增效和药剂与增效作用研究，结果表明：1）江苏常熟二化螟种群对杀虫单已达极高抗水平（抗性倍数126．0），高淳种群为高抗水平（抗性倍数68．40），其它地区也表现为中等抗性，2）吴县、常熟、兴化和高淳4个种群对甲胺磷表现为中等抗性，其它种群抗性较低，3）高淳和宿豫种群对三唑磷为中等抗性，其它种群为敏感群体；（4）活性增效测定测定表明，磷酸三苯酯（TPP）和氧化胡椒基丁醚（PBO）对二化螟有较明显的增效作用，顺丁烯二酸二乙酯（EDM）的增效作用不明显。（5）敌百虫和三唑磷（5：1）、敌百虫和丙溴磷（4：1）、杀虫单和阿维维菌素（40：1：80：1）按质量比进行混配时，增效倍数分别为427、206、1028和210，表现出明显的增效作用。

Studies on resistant measurement to 3 insecticides and the synergisms of synergists and insecticide-mixtures in Chilo suppressalis

Resistant levels of Chilo suppressalis to monosultap,methamidophos and triazophos from 9 locations in Jiangsu Province were examined by useng topical application.The synergistic actions of synergists and insecticide-mixtures were also investigated.The results showed that:1)In Changshu,extreme high level had developed to monosultap( RR =126),Gaochun population was high resistant level to monosultap( RR =46.4),other populations had been middle resistant levels.2)Populations of Wuxian,Changshu,Xinhua and Gaochun have developed to median level resistance to methamidophos,other populations remained low level resistance.3)In Gaochun and Suyu,median level resistance have developed to triazophos,other populations keep susceptible.4)PBO and TPP had synergism to high level resistant populations to methamidophos,with the synergism ratios reached 3.7 and 2.4,while DEM exerted little synergistic.5)4 insecticide-mixtures,i.e. trichlorfon and triazophos (5~{!C~}1,a.i.),trichlorfon and profenophos (4~{!C~}1,a.i.),monosultap and abamectin (4~{!C~}1,80~{!C~}1,a.i.),exhibited significant synergism,with CTCs of 427,206,1?028 and 210,respectively.