耐亚磷酸盐除草剂转基因油菜的创建和抗性评价OA北大核心CSTPCD

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 herbi-cide-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,result-ing in plant growth inhibition.Previously,a ptxD gene isolated from Ralstonia sp.4506,and the mutant protein ptxDQ at position 139,which had tyrosine mutation to glutamine(Y139Q),significantly improved the conversion activity of Phi to Pi.To evaluate the efficacy of ptxDQ/Phi-based weed control system in Brassica napus,we generated transgenic B.napus plants with a codon-optimized ptxD(Y139Q,ptxDQ)gene.Ectopic expression of ptxDQ 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 ptxDQ transgenic lines by supplying Phi,indicating that ptxDQ can transform Phi into Pi in rapeseed.In addition,ptxDQ transgenic Bras-sica napus had a greater competitive growth advantage over wild-type Brassica napus and monocotyledonous weeds(Setaria glauca).In conclusion,the ptxDQ/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.