转基因水稻外源基因的漂移研究

Study on Gene Flow of Transgenic Rice

转基因水稻基因漂移可能带来环境安全性问题。利用农杆菌介导,把hpt基因转化水稻品种,通过后代筛选,以稳定遗传的含单拷贝转化株系为转基因花粉供体材料,研究转基因水稻向非转基因水稻不育系和常规稻(花粉受体)的外源基因漂移频率。结果表明,相邻种植时转基因水稻向雄性不育系品种的漂移频率为31.74%。随距离的增加漂移频率明显下降,在26m处仍能够检测到含外源基因个体的存在,并且在距离4m处出现一个漂移频率的升高;转基因水稻向常规品种的漂移频率则明显低于不育系,一般在2.0%以下,随距离的增加也呈现下降的趋势,在18m处开始无法检测到含外源基因的个体。

Pollen-mediated gene flow from transgenic rice to non-transgenic rice is one of the major concerns in evaluating the environmental safety of transgenic rice varieties.In this study,Zhonghua 11,a Japonica rice cultivar,was transformed with hygromycin phosphotransferase gene（hpt）mediated by Agrobacterium tumefaciems.Stably inherited transgenic lines with single-copy hpt gene were obtained by selection in successive generations,and used as pollen donors.Two non-GM varies,including a male-sterile line and a conventional cultivar,were used as pollen recipients to evaluate the gene flow frequency.The Results obtained showed that the frequency of gene flow to sterile line reached to as high as 31.74%at 0 m,and then decreased dramatically with increasing distance.The seeds with hpt gene could still be detected at the distance of 26 m.Meanwhile,the frequency of gene flow to conventional cultivar was much lower than to sterile line,commonly lower than 2.0%and the decreasing trend was similar to that of sterile line.And the transgene could not be detected at the distance of 18 m.