Mismatch between lab- generated and field- evolved resistance to transgenic Bt crops in Helicoverpa zea

• 成果类型: Article
• 署名作者: Legan, Andrew W.; Allan, Carson W.; Jensen, Zoe N.; Degain, Benjamin A.; Yang, Fei; Kerns, David L.; Benowitz, Kyle M.; Fabrick, Jeffrey A.; Li, Xianchun; Carriere, Yves; Matzkin, Luciano M.; Tabashnik, Bruce E.
• 署名单位: University of Arizona; University of Minnesota System; University of Minnesota Twin Cities; Texas A&M University System; Texas A&M University College Station; Arizona State University; United States Department of Agriculture (USDA); USDA Agricultural Research Service
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-9712
• DOI: 10.1073/pnas.2416091121
• 发表日期: 2024-11-19
• 关键词: bacillus-thuringiensis; insect resistance; toxin resistance; delta-endotoxin; armigera; midgut; cry1ac; proteins; genetics; binding

摘要

Transgenic crops producing crystalline (Cry) proteins from the bacterium Bacillus thuringiensis (Bt) have been used extensively to control some major crop pests. However, many populations of the noctuid moth Helicoverpa zea, one of the most important crop pests in the United States, have evolved practical resistance to several Cry proteins including Cry1Ac. Although mutations in single genes that confer resistance to Cry proteins have been identified in lab- selected and gene- edited strains of H. zea and other lepidopteran pests, the genetic basis of field- evolved resistance to Cry proteins in H. zea has remained elusive. We used a genomic approach to analyze the genetic basis of field- evolved resistance to Cry1Ac in 937 H. zea derived from 17 sites in seven states of the southern United States. We found evidence for extensive gene flow among all populations studied. Field- evolved resistance was not associated with mutations in 20 amplification occurred in a susceptible sample and not in all resistant samples, implying that this amplification does not always confer resistance and mutations in other genes and reflects challenges for managing this pest.