Reichman Jay R, Watrud Lidia S, Lee E Henry, Burdick Connie A, Bollman Mike A, Storm Marjorie J, King George A, Mallory-Smith Carol
Western Ecology Division, US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Corvallis, OR 97333, USA.
Mol Ecol. 2006 Nov;15(13):4243-55. doi: 10.1111/j.1365-294X.2006.03072.x.
Concerns about genetically modified (GM) crops include transgene flow to compatible wild species and unintended ecological consequences of potential transgene introgression. However, there has been little empirical documentation of establishment and distribution of transgenic plants in wild populations. We present herein the first evidence for escape of transgenes into wild plant populations within the USA; glyphosate-resistant creeping bentgrass (Agrostis stolonifera L.) plants expressing CP4 EPSPS transgenes were found outside of cultivation area in central Oregon. Resident populations of three compatible Agrostis species were sampled in nonagronomic habitats outside the Oregon Department of Agriculture control area designated for test production of glyphosate-resistant creeping bentgrass. CP4 EPSPS protein and the corresponding transgene were found in nine A. stolonifera plants screened from 20,400 samples (0.04 +/- 0.01% SE). CP4 EPSPS-positive plants were located predominantly in mesic habitats downwind and up to 3.8 km beyond the control area perimeter; two plants were found within the USDA Crooked River National Grassland. Spatial distribution and parentage of transgenic plants (as confirmed by analyses of nuclear ITS and chloroplast matK gene trees) suggest that establishment resulted from both pollen-mediated intraspecific hybridizations and from crop seed dispersal. These results demonstrate that transgene flow from short-term production can result in establishment of transgenic plants at multi-kilometre distances from GM source fields or plants. Selective pressure from direct application or drift of glyphosate herbicide could enhance introgression of CP4 EPSPS transgenes and additional establishment. Obligatory outcrossing and vegetative spread could further contribute to persistence of CP4 EPSPS transgenes in wild Agrostis populations, both in the presence or absence of herbicide selection.
对转基因作物的担忧包括转基因向可杂交野生种的漂移以及潜在转基因渗入带来的意外生态后果。然而，关于转基因植物在野生种群中的定殖和分布，几乎没有实证记录。我们在此展示了美国境内转基因逃逸到野生植物种群中的首个证据；在俄勒冈州中部的种植区域外发现了表达CP4 EPSPS转基因的抗草甘膦匍匐翦股颖（Agrostis stolonifera L.）植株。在俄勒冈州农业部指定用于抗草甘膦匍匐翦股颖试验生产的控制区域之外的非农业生境中，对三种可杂交翦股颖属物种的本地种群进行了采样。在从20400个样本中筛选出的9株匍匐翦股颖植株中发现了CP4 EPSPS蛋白和相应的转基因（0.04±0.01%标准误）。CP4 EPSPS阳性植株主要位于控制区域边界顺风方向且距离边界最远达3.8公里的湿润生境中；在美国农业部弯曲河国家草原内发现了两株。转基因植物的空间分布和谱系（通过对核ITS和叶绿体matK基因树的分析得以确认）表明，定殖是由花粉介导的种内杂交以及作物种子传播共同导致的。这些结果表明，短期生产中的转基因漂移可导致转基因植物在距离转基因源田或植株数公里远的地方定殖。草甘膦除草剂直接施用或漂移产生的选择压力可能会增强CP4 EPSPS转基因的渗入及更多植株的定殖。无论有无除草剂选择， obligatory异交和营养繁殖可能会进一步促使CP4 EPSPS转基因在野生翦股颖种群中持续存在。 （注：“Obligatory”此处可能有误，推测可能是“Obligate”，但按要求未做修改）
