杀虫药剂混用对棉铃虫乙酰胆碱酯酶和羧酸酯酶的联合抑制作用研究

选用辛硫磷、对硫磷、敌敌畏和氧乐果4种有机磷类杀虫剂以及灭多威和甲萘威两种氨基甲酸酯类杀虫剂分别以1∶1、1∶3和3∶1的比例混用,以棉铃虫Helicoverpa armigera为试虫,分别测得单剂和混剂对其乙酰胆碱酯酶(AChE)和羧酸酯酶(CarE)的抑制中浓度(I50),以联合抑制系数作为增效作用的参考指标进行了比较。研究发现,两种药剂不同配比的混剂对同种酯酶的联合抑制作用也往往不同。对AChE和CarE同时具有抑制作用的只有其中的对硫磷＋甲萘威(1∶3)、辛硫磷+对硫磷(1∶3)和灭多威+氧乐果(1∶3),而甲萘威+敌敌畏(1∶3)、甲萘威＋氧乐果(1∶1)、辛硫磷+甲萘威(1∶1)、对硫磷+氧乐果(1∶1)、对硫磷+氧乐果(1∶3)、敌敌畏+氧乐果(1∶3)、灭多威+对硫磷(1∶1) 7种混剂对AChE和CarE都具有拮抗作用。

Study on Joint-inhibition of Insecticide Mixtures on AChE and CarE in Cotton Bollworm Helicoverpa armigera

Methomyl, carbaryl, phoxim,parathion, dichlorvos and omethoate were mixed each other by the ratio of 1∶1, 1∶3 and 3∶1. Inhibited median concentrations (I50) of these insecticides and their mixtures on acetylcholinesterase (AChE) and carboxylesterase (CarE) in cotton bollworm, Helicoverpa armigera, were tested. The synergism of the mixtures were analyzed by Joint-inhibition coefficient. It was concluded that the JIC of the mixtures to AChE were different from that to CarE, and the JIC of these mixtures varied greatly according to the proportion of the mixture. Parathion +carbaryl(1∶3), phoxim +parathion (1∶3) and methomyl + omethoate(1∶3) were synergistic to AChE and CarE, while carbaryl +dichlorvos(1∶3),carbaryl +omethoate(1∶1),phoxim +carbaryl(1∶1), parathion +omethoate(1∶1), parathion +omethoate(1∶3), dichlorvos + omethoate(1∶3)and methomyl + parathion(1∶1) were antagonistic to AChE and CarE.