Transgenic insecticidal crops and natural enemies: a detailed review of laboratory studies

Environ Entomol. 2009 Apr;38(2):293-306. doi: 10.1603/022.038.0201.

Abstract

This review uses a data-driven, quantitative method to summarize the published, peer-reviewed literature about the impact of genetically modified (GM) plants on arthropod natural enemies in laboratory experiments. The method is similar to meta-analysis, and, in contrast to a simple author-vote counting method used by several earlier reviews, gives an objective, data-driven summary of existing knowledge about these effects. Significantly more non-neutral responses were observed than expected at random in 75% of the comparisons of natural enemy groups and response classes. These observations indicate that Cry toxins and proteinase inhibitors often have non-neutral effects on natural enemies. This synthesis identifies a continued bias toward studies on a few predator species, especially the green lacewing, Chrysoperla carnea Stephens, which may be more sensitive to GM insecticidal plants (16.8% of the quantified parameter responses were significantly negative) than predators in general (10.9% significantly negative effects without C. carnea). Parasitoids were more susceptible than predators to the effects of both Cry toxins and proteinase inhibitors, with fewer positive effects (18.0%, significant and nonsignificant positive effects combined) than negative ones (66.1%, significant and nonsignificant negative effects combined). GM plants can have a positive effect on natural enemies (4.8% of responses were significantly positive), although significant negative (21.2%) effects were more common. Although there are data on 48 natural enemy species, the database is still far from adequate to predict the effect of a Bt toxin or proteinase inhibitor on natural enemies.

Publication types

  • Review

MeSH terms

  • Animals
  • Arthropods* / growth & development
  • Bacterial Proteins / genetics*
  • Crops, Agricultural / genetics*
  • Databases, Factual
  • Endotoxins / genetics*
  • Hemolysin Proteins / genetics*
  • Insect Control / methods*
  • Insecticides*
  • Larva
  • Plants, Genetically Modified*
  • Species Specificity

Substances

  • Bacterial Proteins
  • Endotoxins
  • Hemolysin Proteins
  • Insecticides
  • insecticidal crystal protein, Bacillus Thuringiensis