以哌虫啶和吡蚜酮为参照药剂，评价了环氧虫啶对灰飞虱若虫的毒性，及其在亚致死剂量下对灰飞虱种群增长的影响；同时测定了环氧虫啶在对灰飞虱若虫LC90剂量下喷雾处理后，拟水狼蛛对灰飞虱的捕食功能反应变化。结果表明：环氧虫啶对灰飞虱若虫的毒力依次大于哌虫啶和吡蚜酮。3种杀虫剂在亚致死剂量下对灰飞虱种群增长都有不同程度的抑制作用，其中环氧虫啶的抑制作用最大，表现在处理后的种群趋势指数和相对适合度等参数均极显著低于对照。捕食功能试验表明，3种药剂处理后拟水狼蛛对灰飞虱的捕食仍符合HollingⅡ模型，但出现了猎物的处置时间延长、捕食速率和寻找效应下降，其中环氧虫啶对拟水狼蛛捕食功能的负面影响小于吡蚜酮和哌虫啶。%The toxicity of cycloxaprid to nymphs of Laodelphax striatellus (Fallé n),the effects of cycloxaprid at a sublethal dose on the population growth of L. striatellus,and the change of predatory capacity of Pirata subpi-raticus(Boes. et Str.)after treatment with cycloxaprid at the dose of LC90 to L. striatellus,were investigated,in comparison with paichongding and pymetrozine. Our results showed that the toxicity of cycloxaprid to L. striatel-lus nymphs was greater than that of paichongding and pymetrozine in turn. Inhibited population growth to differ-ent degrees of L. striatellus treated with these three insecticides were observed,among which cycloxaprid caused the most inhibitory effect indicated by very significant reduced parameters of population growth,e.g. index of population trend and relative fitness. The functional response tests revealed that the predatory models of P. sub-piraticus on L. striatellus all conformed to Holling’s type Ⅱ curve when pretreated with lethal doses of these three insecticides. However,the model parameters changed when compared with the control,such as prolonged handling time and reduced searching efficiency. The negative effect of cycloxaprid on predation function of P. subpiraticus was less than that of paichongding and pymetrozine.
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