Insect resistance to Bt crops: evidence versus theory

@article{Tabashnik2008InsectRT,
  title={Insect resistance to Bt crops: evidence versus theory},
  author={Bruce E. Tabashnik and Aaron J Gassmann and David W. Crowder and Yves Carri{\`e}re},
  journal={Nature Biotechnology},
  year={2008},
  volume={26},
  pages={199-202}
}
Evolution of insect resistance threatens the continued success of transgenic crops producing Bacillus thuringiensis (Bt) toxins that kill pests. The approach used most widely to delay insect resistance to Bt crops is the refuge strategy, which requires refuges of host plants without Bt toxins near Bt crops to promote survival of susceptible pests. However, large-scale tests of the refuge strategy have been problematic. Analysis of more than a decade of global monitoring data reveals that the… 
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A suite of models for pyramid Bt crops is analyzed to illustrate factors that should be considered when implementing the high dose-refuge strategy for resistance management; this strategy involves the high expression of toxins in Bt plants and use of non-Bt plants as refuges.
Field-Evolved Insect Resistance to Bt Crops: Definition, Theory, and Data
TLDR
Field outcomes are consistent with predictions from theory, suggesting that factors delaying resistance include recessive inheritance of resistance, abundant refuges of non-Bt host plants, and two-toxin Bt crops deployed separately from one-t toxin BT crops.
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Detailed monitoring data for H. zea and five other pests are consistent with expectations arising from the theory underlying the refuge strategy, suggesting that non-Bt crop refuges help delay insect resistance to Bt crops.
Evolutionary ecology of insect adaptation to Bt crops
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Field‐evolved resistance to Bt crops in only five pests during the last 14 years suggests that the refuge strategy has successfully delayed resistance, but the accumulation of resistant pests could accelerate.
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