采用携带pUbi-Ecppc质粒的3个根癌农杆菌菌株（LBA4404、EHA105和C58c1），对经过预培养10~12 d的春小麦品种扬麦158、Bobwhite和扬麦12的幼胚愈伤组织进行了遗传转化。对筛选中的抗生素浓度、菌液浓度、共培养温度和时间、受体基因型、菌株-质粒组合等影响转化的重要因素进行了研究。首次将单子叶野生C4植物稗草的磷酸烯醇式丙酮酸羧化酶基因（Ecppc）导入小麦受体基因型，并得到具有潮霉素（Hyg）抗性的转化植株。从816块共培养愈伤组织中转化得到34株抗性植株，其中14株PCR检测为阳性。扬麦158的转化效率达3.03%。Southern和RT-PCR分析表明外源基因已整合到小麦基因组并得到正确的转录。生理学检测显示，转基因小麦植株的光合速率和PEPC活性都有所提高。说明Ubiqintin基因启动子控制的稗草PEPC cDNA基因在小麦中可以正确表达和起到一定的生理作用。这些工作为进一步探讨PEPC对小麦光合作用及其他生理过程的影响奠定了基础。
It has long been postulated that the transfer of C4 traits to C3 plants could improve the photosynthetic performance of C3 plant species. Several attempts have been made to transfer C4 photosynthetic traits, with the emphasis on PEPC, to rice plants using genetic engineering techniques. The photosynthetic rates of transgenic rice plants over-expressed PEPC were comparable to those of the untransformed control plants. Recently, maize PEPC gene was first introduced into wheat and the same results were found. These results enlightened us to introduce PEPC into wheat to increase photosynthesis and yield. In this study, wheat calli derived from immature embryos of three cultivars of spring wheat (Yangmai 158, Bobwhite, and Yangmai 12) were cultured for 10 to 12 days and transformed with three strains of Agrobacterium tumefaciens (LBA4404, EHA105, and C58c1) harboring expression vector pUbi-Ecppc which carrying Gus, Hpt, Ecppc genes. Both Gus gene and Hpt gene are promoted by CaMV35S promoter, and Ecppc gene were promoted by maize Ubiquitin promoter. Factors that influence Agrobacterium-mediated wheat transformation, including concentration of antibiotics during selection, concentration of bacterium suspension, temperature and time of co-culture, receptor genotype and bacterium strains, were investigated. With the established wheat genetic transformation system, Ecppc from Echinochloa crusgalli was transferred into wheat firstly and hygomycin resistant plantlets were obtained, with a transformation efficiency of up to 3.03% in Yangmai 158. Fourteen PCR positive transgenic wheat plants from 816 co-cultured calli were obtained and the integration and transcription of transgene was confirmed by Southern blot and RT-PCR analysis. Physiological studies showed that the transformants displayed higher photosynthesis and PEPC activity.
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