Dominant resistance to Bt cotton and minor cross-resistance to Bt toxin Cry2Ab in cotton bollworm from China
Dominant resistance to Bt cotton and minor cross-resistance to Bt toxin Cry2Ab in cotton bollworm from China
复制标题
中国棉铃虫对 Bt 棉花的显性抗性和对 Bt 毒素 Cry2Ab 的轻微交叉抗性
DOI：
10.1111/eva.12099
复制
发表时间：
2013-12-01
影响因子：
4.1
通讯作者：
Wu, Yidong
中科院分区：
文献类型：
--
作者：
Jin, Lin;Wei, Yiyun;Wu, Yidong
害虫抗性的进化威胁到从苏云金芽孢杆菌(Bt)产生杀虫蛋白的转基因作物的长期利益。以前的工作已经发现，来自中国北部的棉铃虫种群对Bt毒素Cry1Ac的抗性频率增加，那里是十几年来广泛种植转Bt基因棉花的地方。为了证实这一趋势，我们报告了2011年的证据显示，在来自中国北部不同省份的两个种群中，对诊断浓度Cry1Ac的抗性个体百分比(1.4%和2.3%)显著高于之前测试的敏感田间种群(0%)。我们分离出了两个抗药性菌株：从两个田间选择的种群中各分离到一个。与敏感品系相比，两个品系对Cry1Ac的抗性分别为460倍和1200倍。这两个菌株对饲料中诊断浓度的Cry1Ac和含有Cry1Ac的转Bt基因棉花叶片均具有显性抗性。两个菌株对Cry2Ab的交叉抗性都很低，分别为4.2倍和5.9倍，Cry2Ab被广泛用作双毒素Bt棉的第二毒素。与其他棉铃虫品系的抗药性相比，这里描述的两个品系的抗药性可能特别难以抑制。
Evolution of resistance by insect pests threatens the long-term benefits of transgenic crops that produce insecticidal proteins from Bacillus thuringiensis (Bt). Previous work has detected increases in the frequency of resistance to Bt toxin Cry1Ac in populations of cotton bollworm, Helicoverpa armigera, from northern China where Bt cotton producing Cry1Ac has been grown extensively for more than a decade. Confirming that trend, we report evidence from 2011 showing that the percentage of individuals resistant to a diagnostic concentration of Cry1Ac was significantly higher in two populations from different provinces of northern China (1.4% and 2.3%) compared with previously tested susceptible field populations (0%). We isolated two resistant strains: one from each of the two field-selected populations. Relative to a susceptible strain, the two strains had 460- and 1200-fold resistance to Cry1Ac, respectively. Both strains had dominant resistance to a diagnostic concentration of Cry1Ac in diet and to Bt cotton leaves containing Cry1Ac. Both strains had low, but significant cross-resistance to Cry2Ab(4.2- and 5.9-fold), which is used widely as the second toxin in two-toxin Bt cotton. Compared with resistance in other strains of H.armigera, the resistance in the two strains characterized here may be especially difficult to suppress.