耐亚磷酸盐除草剂转基因油菜的创建和抗性评价  

Developing and resistance assessing of phosphite-tolerant herbicide transgenic Brassica napus L.

作　　者：钟元 朱天宇 戴成 马朝芝[1] ZHONG Yuan;ZHU Tian-Yu;DAI Cheng;MA Chao-Zhi(National Key Laboratory of Crop Genetic Improvement,Huazhong Agricultural University/National Engineering Research Center of Rapeseed/Hongshan Laboratory,Wuhan 430070,Hubei,China)

机构地区：[1]华中农业大学作物遗传改良全国重点实验室/国家油菜工程技术研究中心/洪山实验室,湖北武汉430070

出　　处：《作物学报》2024年第5期1158-1171,共14页Acta Agronomica Sinica

基　　金：国家自然科学基金项目(32072105)资助。

摘　　要：在油菜的生产过程中,大量伴生的杂草严重影响了其产量和品质。由于近年来田间抗除草剂杂草数量的增加,除草剂的选择正在迅速减少,这影响了未来农业的可持续发展。植物可以通过正磷酸盐(Pi)转运蛋白吸收亚磷酸盐(Phi),但Phi不能被代谢为作物的磷肥料,导致植物生长受到抑制。此前,从罗尔斯通菌属(Raltsonia sp.strain 4506)中分离出了ptxD(phosphite dehydrogenase)基因,其139位的酪氨酸突变为谷氨酰胺(Y139Q)的突变蛋白ptxD_(Q)催化Phi转化为Pi的活性显著提高。为了评价ptxD_(Q)/Phi系统对甘蓝型油菜杂草的防治效果,本研究获得了带有密码子优化的ptxD(Y139Q,ptxD_(Q))基因的转基因甘蓝型油菜。在以Phi为单一磷元素的条件下,ptxD_(Q)转基因油菜可以正常生长,体内Pi含量显著提高,且Pi饥饿响应基因(PT21和PT24等)的表达水平被显著抑制,说明ptxD_(Q)在油菜体内可以促使Phi转化为Pi。此外,ptxD_(Q)转基因油菜具有比野生型油菜和单子叶杂草(狗尾草)更强的生长竞争优势。综上所述,ptxD_(Q)/Phi是一种有效的油菜磷利用和杂草控制系统,既可以抑制杂草的生长,又可以为作物提供充足的Pi营养,从而提高了农业的可持续性。During the production of Brassica napus,the yield and quality of the crop are seriously affected by a large number of accompanying weeds.Herbicide control options are rapidly diminishing due to the recent increase in the number of herbicide-resistant weeds in fields,which affects the sustainable development of agriculture in the future.Plants can take up phosphite(Phi)via orthophosphate(Pi)transporters,but the Phi cannot be metabolized and used as a phosphorus fertilizer for crops,resulting in plant growth inhibition.Previously,a ptxD gene isolated from Ralstonia sp.4506,and the mutant protein ptxD_(Q) at position 139,which had tyrosine mutation to glutamine(Y139Q),significantly improved the conversion activity of Phi to Pi.To evaluate the efficacy of ptxD_(Q)/Phi-based weed control system in Brassica napus,we generated transgenic B.napus plants with a codon-optimized ptxD(Y139Q,ptxD_(Q))gene.Ectopic expression of ptxD_(Q) confered the ability to convert Phi to Pi,resulting in improving plant growth in the presence of Phi.Pi-starvation-induced genes(e.g.PT21 and PT24)were suppressed in the ptxD_(Q) transgenic lines by supplying Phi,indicating that ptxD_(Q) can transform Phi into Pi in rapeseed.In addition,ptxD_(Q) transgenic Brassica napus had a greater competitive growth advantage over wild-type Brassica napus and monocotyledonous weeds(Setaria glauca).In conclusion,the ptxD_(Q)/Phi system provided an effective alternative for suppressing the weed growth while providing adequate Pi nutrition to the crops,which in turn improved the sustainability of agriculture.

关 键 词：甘蓝型油菜 除草剂 亚磷酸盐 ptxD_(Q) 

分 类 号：S565.4[农业科学—作物学]