PDF(Pubmed)
Abstract：
The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), is one of the most important insect pests affecting corn crops worldwide. Although planting transgenic corn expressing Bacillus thuringiensis (Bt) toxins has been approved as being effective against FAW, its populations\' resistance to Bt crops has emerged in different locations around the world. Therefore, it is important to understand the interaction between different Bt proteins, thereby delaying the development of resistance. In this study, we performed diet-overlay bioassays to evaluate the toxicity of Cry1Ab, Cry1Ac, Cry1B, Cry1Ca, Cry1F, Cry2Aa, Cry2Ab, Vip3Aa11, Vip3Aa19, and Vip3Aa20, as well as the interaction between Cry1Ab-, Cry1F-, Cry2Ab-, and Vip3Aa-class proteins against FAW. According to our results, the LC50 values of Bt proteins varied from 12.62 ng/cm2 to >9000 ng/cm2 (protein/diet), among which the Vip3Aa class had the best insecticidal effect. The combination of Cry1Ab and Vip3Aa11 exhibited additive effects at a 5:1 ratio. Cry1F and Vip3Aa11 combinations exhibited additive effects at 1:1, 1:2, and 5:1 ratios. The combination of Cry1F and Vip3Aa19 showed an antagonistic effect when the ratio was 1:1 and an additive effect when the ratio was 1:2, 2:1, 1:5, and 5:1. Additionally, the combinations of Cry1F and Vip3Aa20 showed antagonistic effects at 1:2 and 5:1 ratios and additive effects at 1:1 and 2:1 ratios. In addition to the above combinations, which had additive or antagonistic effects, other combinations exhibited synergistic effects, with variations in synergistic factors (SFs). These results can be applied to the establishment of new pyramided transgenic crops with suitable candidates, providing a basis for FAW control and resistance management strategies.
摘要：
秋季粘虫（一汽），Spodopterafrugiperda（J.E.Smith），是影响全球玉米作物的最重要害虫之一。尽管种植表达苏云金芽孢杆菌（Bt）毒素的转基因玉米已被批准对FAW有效，它的人口对Bt作物的抗性已经在世界各地出现。因此,了解不同Bt蛋白之间的相互作用是很重要的,从而延缓抗性的发展。在这项研究中,我们进行了饮食覆盖生物测定来评估Cry1Ab的毒性，Cry1Ac,Cry1B,Cry1Ca,Cry1F,Cry2Aa,Cry2Ab,Vip3Aa11，Vip3Aa19和Vip3Aa20，以及Cry1Ab-之间的相互作用，Cry1F-,Cry2Ab-,和针对一汽的Vip3Aa类蛋白。根据我们的结果,Bt蛋白的LC50值从12.62ng/cm2到>9000ng/cm2（蛋白质/饮食），其中Vip3Aa类杀虫效果最好。Cry1Ab和Vip3Aa11的组合以5:1的比例表现出累加效应。Cry1F和Vip3Aa11组合在1:1、1:2和5:1的比率下表现出加性效应。Cry1F和Vip3Aa19的组合在比例为1:1时显示拮抗作用,在比例为1:2、2:1、1:5和5:1时显示累加作用。此外,Cry1F和Vip3Aa20的组合在1:2和5:1比例下显示拮抗作用,在1:1和2:1比例下显示加性效应。除了上述组合，具有累加或拮抗作用，其他组合表现出协同作用，协同因子(SFs)的变化。这些结果可用于建立具有合适候选物的新的金字塔转基因作物，为一汽控制和阻力管理策略提供依据。
