转基因抗虫植物对天敌昆虫的影响

The Impact of Insect Resistant Transgenic Crops on Natural Enemies

迄今对 1 6种捕食性和 7种寄生性天敌昆虫个体进行的毒性测定表明 ,转基因植物对天敌昆虫没有直接毒性 ;取食了转基因植物的猎物对大部分捕食性天敌昆虫个体无毒副作用。取食了转基因植物的寄主害虫如表现亚致死反应 ,则对寄生蜂个体无毒副作用 ,甚至对寄生蜂与抗虫作物间有增效作用 ;如寄主表现致死反应 ,则对寄生蜂个体有明显毒副作用。转Bt基因棉花、玉米和马铃薯田中主要广谱捕食性天敌种群数量等于或显著高于常规田 ,生测中对普通草蛉的副作用并未使其大田种群受到不良影响 ;寄生性天敌昆虫种群数量除在个别Bt棉田中明显减少外 ,在其他Bt作物田中均等于或高于常规田。除个别棉田外 ,未发现Bt作物田中天敌群落受到不良影响。部分研究发现Bt作物田中某些非靶标刺吸口器害虫上升为主要害虫 ,数量明显高于常规田。建议采用“三层次检测体系”

Literatures relating to the impact of transgenic crops on natural enemies are reviewed. Some of the general conclusions are summarized as follows. Transgenic crops were not toxic to natural enemies. No detrimental effect was observed on natural enemies feeding on insects of transgenic crops. The populations of general predators and parasitoids in transgenic cotton, maize or potato fields were equal to or higher than those in regular crop fields. In a few fields the population of parasitic insects was significantly decreased. The population of some non target sucking monthpart pests increased significantly to main pest level.