[Objective]Drought is one of the most important constraints resulting in large yield losses and limiting the average yield increase of wheat in China. The aim of this study is to develop and select stable TaSUT1A transgenic wheat lines with resistance to drought.[Method]The open-reading-frame sequence of TaSUT1A was synthesized and used to construct the gene transformation vector pUBI::cas-TaSUT1A, in which TaSUT1A gene was driven by maize ubiquitin promoter and should be highly expressed in monocot plants. Particle bombardment method was used to introduce TaSUT1A into wheat cultivar Kenong 199. After bialaphos screening, DNA PCR and RT-PCR methods were used to detect the presence and transcript levels of TaSUT1A in the transgenic wheat plants of T0-T4 generations. Subsequently, the resistance to water stress of transgenic wheat plants and non-transgenic wheat Kenong 199 at young seedling-stage was evaluated. Further, their determination of physiologic index related to abiotic stress was finished and the potential of improving abiotic stress tolerance in plant was elucidated. [Result]The results indicated that the introduced TaSUT1A gene was stably inherited, and 220%PEG treatment could significantly induce the expression of TaSUT1A in root and leaf tissues of three transgenic wheat lines. The average germination rate of transgenic wheat lines was 85.53%, which was more higher than those of non-transgenic controls, and the average celoeptile and primary root length significantly higher than the non-transgenic plants. The results showed that the transgenic wheat significantly enhanced seed germination in 20%PEG treatment, as indicated by enhancement of the growth of celoeptile and primary root. Further, three pure lines with higher TaSUT1A expression were selected to elucidate physiologic index related to abiotic stress. In detail, in 20% PEG treatment, the transgenic lines overexpressing TaSUT1A increased sucrose and total soluble sugar content in leaf and root, with the average increase value of 42.95% and 36.56% in leaf, and 58.01% and 43.01% in root respectively, which was significantly higher than the non-transgenic plants. After treatment under water stress condition, the MDA content of transgenic plants only increased by 6.12 nmol·g-1FW, however, the MAD content of the non-transgenic plants increased by 19.05 nmol·g-1FW. Meanwhile, the transgenic plant showed better SOD activity, with the average increase value of 44.7 U·g-1FW, which was significantly higher than the non-transgenic plants.[Conclusion]It was concluded that TaSUT1A plays an important role in response to drought stress in plants, overexpression of TaSUT1A can improve significantly tolerance to drought stress in transgenic wheat plants.%【目的】创制过量表达TaSUT1A的转基因小麦，分析TaSUT1A在转基因小麦中的遗传及其对干旱胁迫的应答反应，选育抗旱的转基因小麦新种质。【方法】采用基因重组技术构建了TaSUT1A表达载体，利用基因枪介导法将该载体转入小麦品种科农199，通过Bialaphos筛选、转化植株基因组DNA PCR验证获得转基因T0植株；利用RT-PCR检测TaSUT1A在转基因T3植株中的表达情况，在此基础上，对3个转基因系的T4转基因植株进行抗旱性鉴定和抗旱相关生理指标分析，验证其抗旱能力。【结果】经PCR检测和RT-PCR验证，获得了转TaSUT1A小麦阳性植株，与非转基因对照相比，20%PEG胁迫处理显著诱导了转基因株系根叶组织中目标基因TaSUT1A的上调表达。抗旱鉴定和抗性生理分析显示，在20%PEG 胁迫处理下，转基因株系的萌发率比非转基因对照平均提高了32.8%，显著高于非转基因对照，并促进初生根的萌发和生长，初生根长和胚芽鞘长比非转基因对照平均增加了81.72%和170.77%；在20%PEG胁迫处理下，转基因植株叶组织中的蔗糖和可溶性糖平均提高了42.95%和36.56%，根中蔗糖和可溶性糖平均提高了58.01%和43.01%，均显著高于非转基因对照植株；与未胁迫处理相比，20%PEG胁迫处理后非转基因植株叶中的SOD活性由105.4 U·g-1FW升高到139.1 U·g-1FW，而转基因植株的活性由107.7—115.3 U·g-1FW提高到168.2—211.6 U·g-1FW，显著高于非转基因对照，同时，转基因小麦株系的MDA的产生较非转基因对照平均降低了37.47%，显著减少了MDA的产生。【结论】TaSUT1A在参与植物的逆境应答反应机制中具有重要作用，促进逆境胁迫中小麦的萌发和生长，超量表达TaSUT1A可显著提高转基因小麦的耐旱能力。
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