基因工程树的现状、生态风险与对策

Genetically Engineered Forest Trees: Recent Progress, Ecological Risks and Management Strategies

应用基因工程技术改良树种 ,具有巨大的经济潜力和社会效益。林业生物工程将可能是继农业生物工程之后又一个热潮。目前 ,无论是阔叶树种还是针叶树种的转基因都已获得成功 ,已有几十种转基因树在北美、欧亚大陆、澳洲和非洲释放到野外进行田间试验。尽管当前转基因树木尚未大面积推广种植 ,人们却已对其生态安全性展开了广泛的争论。这是因为转基因树木可能是迄今所有转基因生物中最具生态风险的种类。其主要的生态风险表现在对周围环境中野生树种可能造成基因污染以及转基因树种作为一类新的外来种入侵 ,威胁现今已十分脆弱的地球森林生态系统。一些研究转基因树木的主要国家和实验室已开始注意到应从基因水平上采取防范对策 ,趋利避害 ,以防止或减少转基因树木对自然环境造成不可逆转的污染和破坏。

The biotechnology of forest tree is being developed at a beginning period. It is expected to have the enormous benefits both for economy and society. The introduction and expression of foreign genes were obtained successfully either for hardwoods or conifers. However, the risks of the environmental release of transgenic trees have been concerned and debated widely. The potential impacts of the widespread cultivation of genetically engineered trees exhibit on the possibilities that the natural population in forest ecosystem may occur genetic contamination due to gene flow from transgenic trees and that the genetically engineered trees may become the alien invasive species to threat native biological communities. The basic strategies suggested to avoid the vertical gene transfer between transgenic and natural tree species are the establishment of biological (mainly reproductive sterility) and/or physical barriers.