Early Detection and Mitigation of Resistance to Bt Maize by Western Corn Rootworm (Coleoptera: Chrysomelidae)

Authors

David A. Andow, University of MinnesotaFollow
Steven G. Pueppke, Michigan State UniversityFollow
Arthur W. Schaafsma, University of Guelph, CanadaFollow
Aaron J. Gassmann, Iowa State UniversityFollow
Thomas W. Sappington, USDA-ARS, Corn Insects and Crop Genetics Research UnitFollow
Lance Meinke, University of Nebraska--LincolnFollow
Paul D. Mitchell, University of WisconsinFollow
Terrance M. Hurley, University of MinnesotaFollow
Richard L. Hellmich, Iowa State UniversityFollow
R. Pat Porter, Texas A&M University, LubbockFollow

Document Type

Article

Date of this Version

2015

Citation

J. Econ. Entomol. 1–14 (2015); DOI: 10.1093/jee/tov238

Comments

This work is written by US Government employees and is in the public domain in the US.

Abstract

Transgenic Bt maize that produces less than a high-dose has been widely adopted and presents considerable insect resistance management (IRM) challenges.Western corn rootworm, Diabrotica virgifera virgifera LeConte, has rapidly evolved resistance to Bt maize in the field, leading to local loss of efficacy for some corn rootworm Bt maize events. Documenting and responding to this resistance has been complicated by a lack of rapid diagnostic bioassays and by regulatory triggers that hinder timely and effective management responses. These failures are of great concern to the scientific and agricultural community. Specific challenges posed by western corn rootworm resistance to Bt maize, and more general concerns around Bt crops that produce less than a high-dose of Bt toxin, have caused uncertainty around current IRM protocols. More than 15 years of experience with IRM has shown that high-dose and refuge-based IRM is not applicable to Bt crops that produce less than a high-dose. Adaptive IRM approaches and pro-active, integrated IRM-pest management strategies are needed and should be in place before release of new technologies that produce less than a high-dose.We suggest changes in IRM strategies to preserve the utility of corn rootworm Bt maize by 1) targeting local resistance management earlier in the sequence of responses to resistance and 2) developing area-wide criteria to address widespread economic losses. We also favor consideration of policies and programs to counteract economic forces that are contributing to rapid resistance evolution.