Dong Yufeng, Jin Xi, Tang Qiaoling, Zhang Xin, Yang Jiangtao, Liu Xiaojing, Cai Junfeng, Zhang Xiaobing, Wang Xujing, Wang Zhixing
Biotechnology Research Institute, Chinese Academy of Agricultural SciencesBeijing, China.
Department of Biochemistry, Baoding UniversityBaoding, China.
Front Plant Sci. 2017 May 30;8:885. doi: 10.3389/fpls.2017.00885. eCollection 2017.
Glyphosate is a widely used herbicide, due to its broad spectrum, low cost, low toxicity, high efficiency, and non-selective characteristics. Rice farmers rarely use glyphosate as a herbicide, because the crop is sensitive to this chemical. The development of transgenic glyphosate-tolerant rice could greatly improve the economics of rice production. Here, we transformed the G2 5-enolpyruvyl shikimate-3-phosphate synthase (EPSPS) gene which conferred tolerance to glyphosate herbicide into a widely used rice cultivar, Zhonghua 11 (ZH11), to develop two highly glyphosate-tolerant transgenic rice lines, G2-6 and G2-7, with one exogenous gene integration. Seed germination tests and glyphosate-tolerance assays of plants grown in a greenhouse showed that the two transgenic lines could greatly improve glyphosate-tolerance compared with the wild-type; The glyphosate-tolerance field test indicated that both transgenic lines could grow at concentrations of 20,000 ppm glyphosate, which is more than 20-times the recommended concentration in the field. Isolation of the flanking sequence of transgenic rice G2-6 indicated that the 5'-terminal of T-DNA was inserted into chromosome 8 of the rice genome. An event-specific PCR test system was established and the limit of detection of the primers reached five copies. Overall, the gene significantly improved glyphosate-tolerance in transgenic rice; furthermore, it is a useful candidate gene for the future development of commercial transgenic rice.
草甘膦是一种广泛使用的除草剂，因其具有广谱、低成本、低毒性、高效和非选择性的特点。水稻种植者很少使用草甘膦作为除草剂，因为水稻对这种化学物质敏感。转基因抗草甘膦水稻的开发可以极大地提高水稻生产的经济效益。在此，我们将赋予草甘膦除草剂耐受性的5-烯醇丙酮酰莽草酸-3-磷酸合酶（EPSPS）基因G2转入广泛使用的水稻品种中华11（ZH11）中，以培育出两个具有高草甘膦耐受性的转基因水稻品系G2-6和G2-7，每个品系整合了一个外源基因。种子发芽试验和温室种植植物的草甘膦耐受性测定表明，与野生型相比，这两个转基因品系的草甘膦耐受性有了极大提高；草甘膦耐受性田间试验表明，两个转基因品系在20000 ppm草甘膦浓度下都能生长，这是田间推荐浓度的20多倍。转基因水稻G2-6侧翼序列的分离表明，T-DNA的5'端插入到水稻基因组的第8号染色体中。建立了事件特异性PCR检测系统，引物的检测限达到5个拷贝。总体而言，该基因显著提高了转基因水稻的草甘膦耐受性；此外，它是未来商业化转基因水稻开发的一个有用候选基因。
