马尾松毛虫抗阿维菌素种群的抗性机制及交互抗性

Cross-resistance and biochemical resistance mechanisms of avermectin resistant population of Dendrolimus punctatus

为探讨阿维菌素防治马尾松毛虫的抗性风险和抗性机制,本研究采用叶片浸药法测定了马尾松毛虫抗阿维菌素种群(AV)对多种杀虫剂的交互抗性及增效剂胡椒基丁醚(PBO)、磷酸三苯酯(TPP)和顺丁烯二酸二乙酯(DEM)对马尾松毛虫AV种群、秦岭接官亭种群(JGT)和敏感种群(S)的增效作用,并使用分光光度计测定了AV、JGT和S种群的羧酸酯酶(CarE)、谷胱甘肽转移酶(GST)和多功能氧化酶系(MFOs)活性。结果表明:马尾松毛虫AV种群与甲氨基阿维菌素苯甲酸盐(抗性倍数RR_(50)=25.0)、毒死蜱(RR_(50)=19.0)和高效氯氟氰菊酯(RR_(50)=15.4)存在中等水平交互抗性,与溴虫腈存在低水平交互抗性(RR_(50)=8.1),与乙基多杀菌素、多杀菌素和氯虫苯甲酰胺不存在交互抗性。增效剂PBO与TPP对马尾松毛虫AV、JGT和S种群均有显著增效作用,DEM对马尾松毛虫AV、JGT和S种群均无显著增效作用。马尾松毛虫AV种群MFOs中细胞色素P_(450)含量(3.5倍)、细胞色素b_(5)含量(3.1倍)、O-脱甲基酶活性(4.1倍)和CarE活性(2.2倍)均显著高于S种群,AV种群GST活性与S种群不存在显著性差异。MFOs及CarE活性增强是马尾松毛虫对阿维菌素产生抗性的重要生化机制,推荐乙基多杀菌素、多杀菌素和氯虫苯甲酰胺与阿维菌素轮换使用防治马尾松毛虫。

To identify the resistance risk and the resistance mechanism of avermectin against Dendrolimus punctatus,we examined the cross-resistance of avermectin resistance population(AV)to multiple tested insecticides and the synergism of piperonyl butoxide(PBO),triphenyl phosphate(TPP)and diethyl maleate(DEM)to AV,Qin-ling Jieguanting(JGT)and susceptible(S)popultions,by leaf dipping method.The activities of carboxylesterase(CarE),glutathione S-transferases(GST)and mixed-functional oxidases(MFOs)in AV,JGT and S populations of D.punctatus was measured with spectrophotometry.The results showed that the AV population of D.punctatus had medium level of cross-resistance to emamectin benzoate(resistance ratio,RR_(50)=25.0),chlorpyrifos(RR_(50)=19.0),and cyhalothrin(RR_(50)=15.4),and low level of cross-resistance to chlorfenapyr(RR_(50)=8.1),but no cross-resistance to spinetoram,spinosad and chlorantraniliprole.Both PBO and TPP had significant synergism of avermectin to AV,JGT,and S populations,while DEM had no synergism to all the three populations.Compared with the S population,the AV population had higher content of MFOs cytochromes P_(450)(3.5-fold)and b_(5)(3.1-fold)and the activities of O-demethylase(4.1-fold)and CarE(2.2-fold).There was no significant difference in the activities of GST between AV and S populations.The increasing mixed-functional oxidases and CarE played an important role in the resistance of D.punctatus to avermectin.Spinetoram,spinosad,chlorantraniliprole,and avermectin were recommended to control D.punctatus.