棉铃虫抗药性基因频率的测定(英文)

本文介绍了用单个棉铃虫测定杀虫药剂抗性基因频率的灵敏方法。该技术是基于比较三个相等量单个棉铃虫的乙酰胆碱酯酶的活性，每个棉铃虫要用微量滴定板同时做3个试验（也可用Enppen－dorf管）（No．1－3）：1）不加抑制剂（No．1）；2）不加酶源（No．2）；3）加一定浓度的残杀威以抑制编码敏感AceS等位基因的乙酰胆碱酯酶，但不能抑制编码抗性AceR等位基因的乙酰胆碱酯酶。如果No．1和No．3的强度一样强，说明残杀威对乙酰胆碱酯酶的活性没有影响，那么基因型应是纯合抗性（AceRR，No3＝No．1）。No．2和地．3的强度一样弱时，说明残杀威完全抑制了乙酰碱酯酶的活性，那么基因型应是纯合敏感（AceSS，No．3＝No．2）。No．3的强度介于No．1（强）和No．2（弱）之间显示出残杀威部分地抑制了乙酰胆碱酯酶的活性；基因型是杂合型（AceSR，No．2＜No.3＜No．1）。作者用该方法测定了1995，1996两年从河北省邯郸和固安县棉田采集的棉铃虫，在邯郸棉铃虫抗药性高发地区，其抗性基因频率AceRR分别是68．3％和65．3％；但在棉铃虫抗药性低发区的固安县其抗性基因频率分别是23．9％和29．4％。

SINGLE-HELICOVERPA ARMIGERA TEST TO DETERMINE INSECTICIDE RESISTANCE GENOTYPE FREQUENCY

A sensitive technique for identifying insecticide resistance genotype frequency of the Ace gene existing in natural populations of Helicoverpa armigera in China is described. The technique is based on the comparlson of acetylcholinesterase (AChE) activity in 3 equal aliquots , which are taken from the homogenate of a single H. armigera: 1) in absence of inhibitor (well No. 1); 2) in absence of enzyme precursor (well No. 2); and 3) in presence of a concentration of propoxur inhlbltlng the AChE coded by the AceS allele hut not by the AceR allele (well No. 3). An intensity of same strength in wells No. 1 and No. 3 indicates that propoxur has no effect on AChE activity, and the genotype should be Ace',(when well No. 3 =well No. 1 ). A same weak intensity in well No. 2 and No. 3 (and a strong intensity in well No. 1 ), indicates that propoxur completely inhibited AChE activity; and the genotype should be AceSS(when well No. 3=well No. 2). Well No. 3 displaying an lnterrnediate in- tensity between well No. 1 (strong intensity) and well No. 2 (weak intensity) indicates that AchE activity was partially inhihited by the propoxur concentratlon and genotype should he Ace,, (when well No. 2