Department of Entomology, University of Arizona, Tucson, AZ, USA.
USDA ARS, U. S. Arid Land Agricultural Research Center, Maricopa, AZ, USA.
J Econ Entomol. 2023 Apr 24;116(2):297-309. doi: 10.1093/jee/toac183.
Crops genetically engineered to produce insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) have improved pest management and reduced reliance on insecticide sprays. However, evolution of practical resistance by some pests has reduced the efficacy of Bt crops. We analyzed global resistance monitoring data for 24 pest species based on the first 25 yr of cultivation of Bt crops including corn, cotton, soybean, and sugarcane. Each of the 73 cases examined represents the response of one pest species in one country to one Bt toxin produced by one or more Bt crops. The cases of practical resistance rose from 3 in 2005 to 26 in 2020. Practical resistance has been documented in some populations of 11 pest species (nine lepidopterans and two coleopterans), collectively affecting nine widely used crystalline (Cry) Bt toxins in seven countries. Conversely, 30 cases reflect no decrease in susceptibility to Bt crops in populations of 16 pest species in 10 countries. The remaining 17 cases provide early warnings of resistance, which entail genetically based decreases in susceptibility without evidence of reduced field efficacy. The early warnings involve four Cry toxins and the Bt vegetative insecticidal protein Vip3Aa. Factors expected to favor sustained susceptibility include abundant refuges of non-Bt host plants, recessive inheritance of resistance, low resistance allele frequency, fitness costs, incomplete resistance, and redundant killing by multi-toxin Bt crops. Also, sufficiently abundant refuges can overcome some unfavorable conditions for other factors. These insights may help to increase the sustainability of current and future transgenic insecticidal crops.
经过基因工程改造、能够生产苏云金芽孢杆菌（Bacillus thuringiensis，Bt）杀虫蛋白的作物，改善了虫害管理，减少了对杀虫剂喷雾的依赖。然而，一些害虫实际抗性的进化降低了 Bt 作物的功效。我们分析了基于 Bt 作物种植前 25 年的全球 24 种害虫抗性监测数据，包括玉米、棉花、大豆和甘蔗。每 73 个案例代表一个国家的一种害虫对一种或多种 Bt 作物产生的一种 Bt 毒素的反应。实际抗性的案例从 2005 年的 3 例增加到 2020 年的 26 例。在 11 种害虫（9 种鳞翅目和 2 种鞘翅目）的一些种群中已经记录到了实际抗性，这些害虫共同影响了 7 个国家的 7 种广泛使用的 Cry Bt 毒素。相反，在 10 个国家的 16 种害虫种群中，有 30 个案例反映了对 Bt 作物的敏感性没有降低。其余 17 个案例提供了抗性的早期预警，这些预警涉及敏感性的遗传基础降低，但没有田间功效降低的证据。早期预警涉及四种 Cry 毒素和 Bt 营养体杀虫蛋白 Vip3Aa。预计有利于持续敏感性的因素包括非 Bt 宿主植物丰富的避难所、抗性的隐性遗传、低抗性等位基因频率、适应成本、不完全抗性和多毒素 Bt 作物的冗余杀伤。此外，足够丰富的避难所可以克服其他因素的一些不利条件。这些见解可能有助于提高当前和未来转基因杀虫作物的可持续性。
