USDA-ARS, Beneficial Insects Introduction Research Unit, , Newark, DE 19713, USA.
Biol Lett. 2010 Feb 23;6(1):74-7. doi: 10.1098/rsbl.2009.0612. Epub 2009 Sep 9.
The tiered approach to assessing ecological risk of insect-resistant transgenic crops assumes that lower tier laboratory studies, which expose surrogate non-target organisms to high doses of insecticidal proteins, can detect harmful effects that might be manifested in the field. To test this assumption, we performed meta-analyses comparing results for non-target invertebrates exposed to Bacillus thuringiensis (Bt) Cry proteins in laboratory studies with results derived from independent field studies examining effects on the abundance of non-target invertebrates. For Lepidopteran-active Cry proteins, laboratory studies correctly predicted the reduced field abundance of non-target Lepidoptera. However, laboratory studies incorporating tri-trophic interactions of Bt plants, herbivores and parasitoids were better correlated with the decreased field abundance of parasitoids than were direct-exposure assays. For predators, laboratory tri-trophic studies predicted reduced abundances that were not realized in field studies and thus overestimated ecological risk. Exposure to Coleopteran-active Cry proteins did not significantly reduce the laboratory survival or field abundance of any functional group examined. Our findings support the assumption that laboratory studies of transgenic insecticidal crops show effects that are either consistent with, or more conservative than, those found in field studies, with the important caveat that laboratory studies should explore all ecologically relevant routes of exposure.
抗虫转基因作物生态风险评估的分层方法假设，较低层次的实验室研究，即暴露替代非靶标生物于高剂量的杀虫蛋白，可以检测到可能在田间表现出来的有害影响。为了验证这一假设，我们进行了元分析，比较了在实验室研究中暴露于苏云金芽孢杆菌（Bt）Cry 蛋白的非靶标无脊椎动物的结果与独立的田间研究中检查对非靶标无脊椎动物丰度影响的结果。对于鳞翅目活性的 Cry 蛋白，实验室研究正确预测了非靶标鳞翅目在田间的减少丰度。然而，包含 Bt 植物、食草动物和寄生蜂三重营养相互作用的实验室研究与寄生蜂减少的田间丰度相关性更好，而不是直接暴露于杀虫剂的研究。对于捕食者，实验室三重营养研究预测的减少丰度并未在田间研究中实现，因此高估了生态风险。接触鞘翅目活性的 Cry 蛋白并没有显著降低任何功能组的实验室存活率或田间丰度。我们的研究结果支持这样的假设，即转基因杀虫作物的实验室研究显示的影响与田间研究一致，或者更保守，一个重要的警告是，实验室研究应该探索所有生态相关的暴露途径。
