Rose Robyn, Dively Galen P
Biotechnology Regulatory Services, USDA, Animal and Plant Health Inspection Service, Unit 147, 4700 River Rd., Riverdale, MD 20737, USA.
Environ Entomol. 2007 Oct;36(5):1254-68. doi: 10.1603/0046-225X(2007)36[1254:EOIALB]2.0.CO;2.
A field study was conducted over 2 yr to determine the effects of transgenic sweet corn containing a gene from the bacterium Bacillus thuringiensis (Bt) on the diversity and abundance of nontarget arthropods. The Bt hybrid (expressing Cry1Ab endotoxin for lepidopteran control) was compared with near-isogenic non-Bt and Bt hybrids treated with a foliar insecticide and with a near-isogenic non-Bt hybrid without insecticides. Plant inspections, sticky cards, and pitfall traps were used to sample a total of 573,672 arthropods, representing 128 taxonomic groups in 95 families and 18 orders. Overall biodiversity and community-level responses were not significantly affected by the transgenic hybrid. The Bt hybrid also had no significant adverse effects on population densities of specific nontarget herbivores, decomposers, and natural enemies enumerated at the family level during the crop cycle. As expected, the insecticide lambda-cyhalothrin had broad negative impacts on the abundance of many nontarget arthropods. One insecticide application in the Bt plots reduced the overall abundance of the natural enemy community by 21-48%. Five applications in the non-Bt plots reduced natural enemy communities by 33-70%. Nontarget communities affected in the insecticide-treated Bt plots exhibited some recovery, but communities exposed to five applications showed no trends toward recovery during the crop cycle. This study clearly showed that the nontarget effects of Bt transgenic sweet corn on natural enemies and other arthropods were minimal and far less than the community-level disruptions caused by lambda-cyhalothrin.
进行了一项为期两年的田间研究，以确定含有来自苏云金芽孢杆菌（Bt）基因的转基因甜玉米对非靶标节肢动物多样性和丰度的影响。将表达Cry1Ab内毒素用于防治鳞翅目害虫的Bt杂交种与近等基因非Bt杂交种、用叶面杀虫剂处理的Bt杂交种以及未使用杀虫剂的近等基因非Bt杂交种进行比较。通过植株检查、粘虫板和陷阱诱捕器共采集了573,672只节肢动物，代表95个科、18个目的128个分类群。转基因杂交种对整体生物多样性和群落水平的反应没有显著影响。Bt杂交种对作物生长周期内家庭层面列举的特定非靶标食草动物、分解者和天敌的种群密度也没有显著不利影响。正如预期的那样，高效氯氟氰菊酯杀虫剂对许多非靶标节肢动物的丰度有广泛的负面影响。在Bt地块施用一次杀虫剂使天敌群落的整体丰度降低了21%-48%。在非Bt地块施用五次杀虫剂使天敌群落减少了33%-70%。在施用杀虫剂的Bt地块中受到影响的非靶标群落表现出一定程度的恢复，但在作物生长周期内，接受五次施用的群落没有恢复趋势。这项研究清楚地表明，Bt转基因甜玉米对天敌和其他节肢动物的非靶标影响极小，远小于高效氯氟氰菊酯对群落水平的破坏。
