重组增效蛋白对Bt和氯氰菊酯防治棉铃虫的增效作用

前期在大肠杆菌中表达得到具有显著生物活性的含粉纹夜蛾颗粒体病毒增效蛋白C端818个氨基酸的融合蛋白P96。以毒饲料法研究P96对苏云金芽孢杆菌和氯氰菊酯杀棉铃虫敏感、抗性品系的增效作用。结果表明：P96对Bt杀棉铃虫敏感、低抗、中抗品系的增效比分别为3．34、4．72和9．82；对氯氰菊酯杀棉铃虫敏感、低抗、中抗品系的增效比分别为2．53、3．38和6．24。随棉铃虫抗性升高，P96的增效作用愈为明显。单对汰选是快速选育棉铃虫抗Bt品系的有效方法。

Synergism of Recombinant Enhancin to Bacillus thuringiensis and Cypermethrin against the Larvae of Helicoverpa armigera

A recombinant enhancin from Trichoplusia ni granulovirus had been expressed successfully in Escherichia coli and named as P96 in the previous study.In this paper,a series bioassay was conducted to characterize the synergy of P96 to Bacillus thuringiensis(Bt) and cypermethrin against the larvae of Helicoverpa armigera. The results indicated that P96 increased the toxicity of Bt and cypermethrinmarkedly to their susceptible,low-resistant and mid-resistant strains of H.armigera, the synergy ratio were 3.34,4.72,9.82 for Bt and 2.53,3.38,6.24 for cypermethrin,respectively.With the increase of resistance ratio,the synergy ratio of P96 also increased.Single-pair selection is an effective approach to speed up insect resistance in laboratory.