【摘要】 <正> 根据拟除菊酯—杀虫脒合剂对棉铃虫等多种夜蛾科幼虫具有增效作用特性(7,14),我们通过室内触杀毒力试验和两个棉区一、二年田间药效试验,初步发现杀灭菊酯—杀虫脒盐酸盐(1:5—10)合剂对棉蚜也具有明显的增效效果。通过合剂的应用,杀灭菊酯高效控制棉蚜的经济施药剂量可较大幅度降低,这对促进棉花生产、降低进成本具有现实意义。现初步报导于下。更多还原

【Abstract】 Laboratory and two year’s field tests were conducted for syne- rgism studies with mixtures of fenvalerate plus chlordimeform-HCl against cotton aphids.We preliminarily discovered that the already high toxicity of fenvalerate to cotton aphids could be increased signi- ficantly when these two insecticides were combined(1:5→10).Through application of these mixtures,the highly effective dose of fenvalerate can be reduced very probably to ultra-low application dose level(～15 g a.i./ha)We also discovered that,through mixing with chlordimeform -HCl:very low fenvalerate dose(15→22.5 g a.i./ha)still provided superior residual protection of both seriously aphid-infested buds and leaves of cotton seedlings,whereas the ordinary aphicides provided only inferior proteive action on buds.These findings may prove to be of practical signigicance for enhancing economic benefits of fenvalerate appications in cotton production. The mechanism by which chlordimeform-HCl synergizes pyrethroids is not known.Based on the fact that chlordimeform was a good substr- ate for microsomal oxidases and the published data no the metabolism of pyrethroids in certain insects,and in addition,based on the fact that fenvalerate:triphenyl phosphate combination(TPP-a potent insect hydrolyzing esterase inhibitor)did not possess synergism against cot- ton aphids,we suggest that inhibition of oxidative detoxication in cotton aphids may probably be involved in the case of fenvalerate at lcast. The lack of published data on the complicated metabolism of fenval- erate by cotton aphids makes conclusions on the nature of this synergism more speculative. In view of the fact that investigations on synergism of pyrethroids by important insect target enzme inhibitors against economic cotton pests have both theoretical and practical significance,more work needs certainly to be conducted to elucidate the exact mechanisms responsible for the synergistic activity of these mixtures.更多还原