抗Bt杀虫蛋白棉铃虫种群的相对适合度

Relative Fitness of Bt ICP-resistant Population of Helicoverpa armigera Hübner

在室内条件下 ,比较了对苏云金杆菌 (Bacillus thuringiensis,Bt)杀虫蛋白 (ICP)有 2 0倍抗性的棉铃虫 (H elicoverpa armigera Hübner)种群 (R种群 )与同源对照种群 (S种群 )之间的相对适合度。结果表明 ,与 S种群相比 ,R种群的产卵量、卵孵化率和化蛹率明显降低 ,幼虫历期和蛹历期明显延长 ,R种群相对于 S种群的适合度为 0 .6 5。杂交 F1代 RS种群相对于 S种群的适合度为 1.6 ,显示出杂交优势。正反交 F1代种群对 Bt ICP敏感性的差异不显著 ,表明棉铃虫对 Bt ICP的抗性遗传不存在性连锁 ,为常染色体遗传。

Relative fitness of the R, the homologous control population(S), and the F1 hybrids(RS) were tested.The results showed that there were significantly fewer eggs per female, lower egg hatchability and pupation rate, and significantly longer duration of larva and pupa in R population compared with that in S population.Relative fitness of R population is only 0.65 based on comparing R 0 of R population with R 0 of S population, but the value is 1.6 in RS population. The results indicated that there are some reproductive disadvantages in R population. No significant difference of toxicity of Cry1Ac to the two reciprocal cross populations between R and S populations was observed. This indicated that the resistance to Bt ICP was inherited as antosomal factor.