Insect resistance to Bt crops: lessons from the first billion acres

  title={Insect resistance to Bt crops: lessons from the first billion acres},
  author={Bruce E. Tabashnik and Thierry Br{\'e}vault and Yves Carri{\`e}re},
  journal={Nature Biotechnology},
Evolution of resistance in pests can reduce the effectiveness of insecticidal proteins from Bacillus thuringiensis (Bt) produced by transgenic crops. We analyzed results of 77 studies from five continents reporting field monitoring data for resistance to Bt crops, empirical evaluation of factors affecting resistance or both. Although most pest populations remained susceptible, reduced efficacy of Bt crops caused by field-evolved resistance has been reported now for some populations of 5 of 13… 

Surge in insect resistance to transgenic crops and prospects for sustainability

Global monitoring data reported during the first two decades of transgenic crops was analyzed, with each case representing the responses of one pest species in one country to one insecticidal protein from Bacillus thuringiensis (Bt).

Successes and failures of transgenic bt crops: Global patterns of field-evolved resistance

This work reviews data monitoring resistance to seven Bt proteins in 13 major pest species targeting Bt maize and Bt cotton on six continents and encourages collaboration between growers and scientists in industry, academia and government to implement large refuges of non-Bt host plants to maximize the benefi ts of Bt crops.

Resistance to Bt Crops; Influence, mechanisms and management strategies

Understanding the Bt resistance mechanisms, including the molecular basis of resistance is important for well-resistance control in Bt crops.

Advances in Managing Pest Resistance to Bt Crops: Pyramids and Seed Mixtures

It is suggested that an effective refuge percentage of at least 20 % is required to substantially delay pest resistance, even when pyramids, seed mixtures, or both are used.

Global Patterns of Resistance to Bt Crops Highlighting Pink Bollworm in the United States, China, and India

The global monitoring data reviewed here reveal 19 cases of practical resistance to Bt crops, which is field-evolved resistance that reduces Bt crop efficacy and has practical consequences for pest control.

Dominance and fitness costs of insect resistance to genetically modified Bacillus thuringiensis crops

The quantitative analysis of the global data documents that the prevalence of non-recessive resistance has played an essential role in the widespread evolution of resistance to Bt crops, while the lack of fitness costs is apparently not as critical as the non- recessive resistance.

Pest control and resistance management through release of insects carrying a male-selecting transgene

It is concluded that MS insects offer an effective and versatile control option against P. xylostella and potentially other pests, and may reduce reliance on and protect insecticide-based approaches, including Bt crops.

Hybridizing transgenic Bt cotton with non-Bt cotton counters resistance in pink bollworm

A strategy for combating resistance by crossing transgenic Bt plants with conventional non-Bt plants and then sowing the second-generation seeds yields a random mixture within fields of three-quarters of plants that produce Bt toxin and one-quarter that does not, which implies that this strategy countered evolution of resistance.

Fitness costs associated with Cry1F resistance in the European corn borer

Fitness costs associated with Cry1F resistance in O. nubilalis when insects were reared on three maize lines are examined to contribute to the maintenance of Cry1f susceptibility in field populations more than a decade afterCry1F maize was commercialized.



Insect resistance to Bt crops: evidence versus theory

Analysis of more than a decade of global monitoring data reveals that the frequency of resistance alleles has increased substantially in some field populations of Helicoverpa zea, but not in five other major pests in Australia, China, Spain and the United States.

Evolutionary ecology of insect adaptation to Bt crops

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.

Field-Evolved Insect Resistance to Bt Crops: Definition, Theory, and Data

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.

Delayed resistance to transgenic cotton in pink bollworm

A synthesis of experimental and modeling results suggests that this delay in resistance to pink bollworm can be explained by refuges of cotton without Bt toxin, recessive inheritance of resistance, incomplete resistance, and fitness costs associated with resistance.

Suppressing resistance to Bt cotton with sterile insect releases

Computer simulations show that this approach works in principle against pests with recessive or dominant inheritance of resistance, and during a large-scale, four-year field deployment of this strategy in Arizona, resistance of pink bollworm to Bt cotton did not increase.

Early Warning of Cotton Bollworm Resistance Associated with Intensive Planting of Bt Cotton in China

Responsibility to Cry1Ac was significantly lower in 13 field populations from northern China, where Bt cotton has been planted intensively, than in two populations from sites in northwestern China where exposure to Bt Cotton has been limited, implying that resistance toCry1Ac in northern China is a specific adaptation caused by exposure to this toxin in Btotton.

Delaying evolution of insect resistance to transgenic crops by decreasing dominance and heritability

The refuge strategy is used widely for delaying evolution of insect resistance to transgenic crops that produce Bacillus thuringiensis (Bt) toxins. Farmers grow refuges of host plants that do not

Sustained susceptibility of pink bollworm to Bt cotton in the United States.

Sustained susceptibility of pink bollworm to Bt cotton in Arizona has provided a cornerstone for the pink bollsworm eradication program and for integrated pest management in cotton, and it is encouraged to combine Bt crops with other tactics in integrated pestmanagement programs.

Fitness costs of insect resistance to Bacillus thuringiensis.

Modeling results show that fitness costs can delay resistance by selecting against Bt-resistant genotypes in refuges where insects are not exposed to Bt toxins, andRefuges designed to increase the dominance or magnitude of fitness costs could be especially useful for delaying pest resistance.

Potential shortfall of pyramided transgenic cotton for insect resistance management

Analysis of results from 21 selection experiments with eight species of lepidopteran pests indicates that some cross-resistance typically occurs between Cry1A and Cry2A toxins, and incorporation of empirical data into simulation models shows that the observed deviations from ideal conditions could greatly reduce the benefits of the pyramid strategy.