Pest Management Science (2016) 72, 190-198

Jennifer Deitloff, Mike W. Dunbar, David A. Ingber, Bruce E. Hibbard and Aaron J. Gassmann (2016)
Effects of refuges on the evolution of resistance to transgenic corn by the western corn rootworm, Diabrotica virgifera virgifera LeConte
Pest Management Science 72 (1), 190-198
Abstract:
BACKGROUND
Diabrotica virgifera virgifera LeConte is a major pest of corn and causes over a billion dollars of economic loss annually through yield reductions and management costs. Corn producing toxins derived from Bacillus thuringiensis (Bt) has been developed to help manage D. v. virgifera. However, previous studies have demonstrated the ability of this species to evolve resistance to Bt toxins in both laboratory and field settings.
RESULTS
We used an experimental evolution approach to test the refuge strategies for delaying resistance of D. v. virgifera to corn producing Bt toxin Cry34/35Ab1. In the absence of refuges, D. v. virgifera developed resistance to Bt corn after three generations of selection. In some cases, non-Bt refuges reduced the level of resistance compared with the strain selected in the absence of refuges, but refuge strains did show reduced susceptibility to Bt corn compared with the unselected strain.
CONCLUSIONS
In this study, non-Bt refuges delayed resistance to Bt corn by D. v. virgifera in some cases but not others. Combining the refuge strategy with pyramids of multiple Bt toxins and applying other pest management strategies will likely be necessary to delay resistance of D. v. virgifera to Bt corn.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Bruce E. Hibbard, Aaron J. Gassmann

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
resistance/tolerance/defence of host

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Diabrotica virgifera	Maize/corn (Zea mays)
Bacillus thuringiensis Cry34A/Cry35A-toxin (entomopathogen)	Diabrotica virgifera	Maize/corn (Zea mays)