靶标害虫对Bt玉米的抗性发展和治理策略

Evolution of resistance to transgenic Bacillus thuringiensis maize in pest insects and a strategy for managing this

全生育期有效表达Bt杀虫蛋白的转基因抗虫玉米为靶标害虫的防治提供了新途径。但是,靶标害虫抗性种群的发展严重威胁了转基因抗虫玉米的可持续应用。截止到2018年,已经有13例报道表明靶标害虫对转基因抗虫玉米产生了田间抗性;5例监测结果表明靶标种群没有降低对Bt玉米的敏感性,其中包括转vip3Aa玉米。抗性治理策略成功的关键主要包括:Bt杀虫蛋白的高剂量表达、靶标害虫的隐性遗传、初始抗性等位基因频率较低、不完全抗性、适合度代价等。当抗性为非隐性遗传时,可以通过增加庇护所的种植面积达到延缓抗性发展的目的。

Transgenic Bacillus thuringiensis maize expressing Bt toxins is a new tool for controlling target pest insects.However, the evolution of resistance within target pest populations threatens the sustainable utilization of Bt maize. By 2018 about 13 cases of resistance to Bt maize have been reported. In 5 other cases there was no significant decrease in susceptibility to Bt maize, including transgenic maize that produces the Vip3 Aa protein. Factors that favor a successful resistance management strategy that can delay resistance include high-dosages, the recessive inheritance of resistance, low frequency of the alleles that confer resistance, incomplete resistance and fitness costs. When the inheritance of resistance is not recessive,increasing the size of refugia can still significantly delay the development of resistance.