德国小蠊的抗性监测及乙酰胆碱酯酶活性研究

目的明确南昌市德国小蠊对几种常用杀虫剂的抗性现状及乙酰胆碱酯酶(AChE)在抗性中的作用,为建立一种快速、灵敏的生化检测方法和蟑螂的化学药剂控制提供科学依据。方法采用药膜法测定德国小蠊对5种常用杀虫剂的抗性水平,酶活性的测定参照Ellman(1961)的方法。结果德国小蠊对残杀威、溴氰菊酯、高效氯氰菊酯、右旋反式丙炔菊酯和敌敌畏的抗性指数分别为1.091 6、1.364 7、4.991 5、5.251 9、>122.261 8倍。对德国小蠊抗性和敏感品系AChE活力比较结果表明,抗性品系AChE比活力相对于敏感品系明显降低,差异达极显著水平(P<0.01),而且抗性品系的Km值也显著升高(P<0.01),说明AChE发生了质变,导致酶和底物的结合能力显著降低,敏感度显著降低。结论德国小蠊野外品系除对残杀威和溴氰菊酯较敏感外,对敌敌畏产生了高度抗性,对高效氯氰菊酯和右旋反式丙炔菊酯也都产生了一定程度的抗性,两者的抗性水平相当。对AChE的活性及动力学研究结果表明AChE敏感度降低与德国小蠊对有机磷、氨基甲酸酯和菊酯类杀虫剂产生的抗性密切相关。

Resistance detection and acetylcholinesterase activity on Blattella germanica

Objective To understand the resistance level of 5 conventional insecticides against Blattella germanica and the role of acetylcholinesterase(AChE) in resistance.Methods Medicine film method was used to determine the resistance level of B.germanica,while AChE activity and its kinetic parameters were determined according to the method of Ellman et al.(1961).Results The resistance factor values of 5 insecticides against B.germanica were 1.091 6(propoxur),1.364 7(deltamethrin),4.991 5(high effect cypermethrin),5.251 9(prallethrin) and>122.261 8(dichlorvos) fold,respectively.The specific activity of resistant strain was decreased significantly(P< 0.01),and Km value was obviously higher than that of susceptible strain(P< 0.01).The results suggested that the structure of AChE changed.Therefore,the sensitivity on insecticides was reduced.Conclusion In addition to propoxur and deltamethrin,the field strain of B.germanica had developed high resistance to dichlorvos,high effect cypermethrin and prallethrin in some degree.The biochemistry results indicated that decreased AChE sensitivity was closely correlated to the resistance development of B.germanica.