五种杀虫剂对圆果大赤螨毒力及其对假眼小绿叶蝉捕食作用的影响

测定了印楝素、吡虫啉、赛丹、天王星和敌敌畏5种杀虫剂对圆果大赤螨的毒力,及其对茶假眼小绿叶蝉捕食作用的影响。结果表明,印楝素和吡虫啉对圆果大赤螨的毒性和捕食功能影响较小,其它3种农药影响较大;亚致死剂量杀虫剂对圆果大赤螨功能反应模型的基本结构没有改变,但影响到了模型的各项参数,药剂处理后圆果大赤螨最大日捕食量降低,处理猎物的时间延长,捕食速率和寻找效应减弱,说明亚致死剂量杀虫剂对天敌圆果大赤螨的捕食作用存在着不良影响。

Toxicity of Five Insecticides on Predatory Mite(Anystis baccarum L.) and Their Effects on Predation to Tea Leafhopper (Empoasca vitis G(o)the)

The toxicity of five insecticides, azadirachtin, imidacloprid, endosulfan, biphenthrin and DDVP, on predatory mite (Anystis baccarum L), and effects on the functional response of A. baccarum mite in preying the tea leafhopper (Empoasca vitis (G?the)) were investigated. Results revealed that, in contrast to other kinds of insecticide, azadirachtin, imidacloprid showed a rather weak toxicity and less influence on the predation function of A. baccarum mite; the functional response model of A. baccarum mite preying on tea leafhopper were all conformed to Holling’s type II curve in spite of pretreated with sublethal doses of these insecticides. However, there were some changes in the parameters of the model, e.g., the maximal predatory capacities of A. baccarum mite that pretreated with sublethal dose of insecticides were reduced, the handling time was prolonged, the predatory rates were declined, and the searching capability were weakened than that of control. These findings suggested that insecticides at sublethal level had harmful influence on the predation of A. baccarum mite.