利用叶蝉评价转基因玉米对非靶标生物的风险

An Evaluation of Methods for Assessing the Impacts of Bt-maize on Non-target Organisms with Leafhoppers

转基因抗虫作物应用是替代杀虫剂的重要途径。但转基因作物可能存负面效应,特别是对非靶标生物的影响及害虫产生抗性。采用直接和陷阱调查结合方法,连续多年对转Cry1Ac抗虫基因玉米实验田叶蝉和主要节肢动物数量动态跟踪调查,结果发现叶蝉是玉米田优势非靶标生物种群之一,中期发生比例占刺吸式害虫的28.9%~43.1%,且种群动态与主要非靶标节肢动物群落动态基本一致。又鉴于叶蝉直接刺吸接触到Bt杀虫蛋白,可直接反映转基因作物对非靶标生物的安全性,因此可利用叶蝉作为转基因抗虫玉米安全性评价指示生物来评价转基因玉米对非靶标生物群落风险,田间测试结果证明此方法是可行的。

The application of transgenic insect-resistant crops has been an important way to replace insecticides. But transgenic insect-resistant crops have potential negative effects, especially the effect on the non-target organisms and resistance to GM. Visual assessment and yellow traps were used for investigating the dynamic of leafhoppers and main arthropods in CrylAc transgenic insect-resistant corn field for two years. The study showed that planthoppers and leafhoppers were highly abundant and diverse in maize fields, their mid- term occurrence was 28.9%-43.1% of sucking pest insects, and the population dynamic had no significant difference between Bt-maize and the untreated near-isogenic maize. Leafhoppers were directly exposed to these entomotoxic proteins and could also serve as a source of Cry protein exposure to predatory arthropods. Therefore, it was reasonable to use Auchenorrhyncha in the risk assessment of GM corn. So the risk of Bt corn on non-target organisms could be evaluated using leafhoppers as an indicator species. The results in field tests showed that this method was feasible.