With the seedling shoot tips of maize inbred line ‘Ye 478’ as explants, the SAMS gene was transferred into the maize by using Agrobacterium-mediated transformation. The transgenic maize were identified by PCR and RT-PCR, T1 transgenic maize and non-modified maize were treated with 18％ PEG-6000 to simulate drought stress conditions. The results prove that 453 transgenic plants were obtained after having transformed 518 shoot tips and 16 T0 positive transgenic plants were screened by PCR. The frequency of transformation reached 3.53％, 14 of them get seeds finally. 9 of T1 transgenic maize were transcription normally confirmed by RT-PCR. The study found that leaf relative water content,chlorophyll content,proline content and SOD activity of transgenic maize were higher than that of CK plants, while conductance and MDA content were lower under the same water stress time. When the time reached 60 h, leaf relative water content, chlorophyll content, proline content and SOD activity of transgenic maize were 8. 16％,20.02％, 32.21％, 22.77％ higher than the corresponding physiological indexes of CK, but conductance and MDA content were 14.38％,29.41％ lower than that in CK. We can conclude that genetically modified maize has improved the drought-resistance by introducing foreign SAMS genes.%以玉米自交系'掖478'的茎尖为受体,采用农杆菌介导法将小麦抗旱SAMS基因转入玉米中,用PCR和RT-PCR法对转化玉米进行检测,并以18%PEG-6000模拟水分胁迫对T1代转基因玉米和非转基因玉米进行抗旱性分析.结果显示:(1)共转化518个玉米芽,得到453株转化苗.获得T0代阳性植株16株,转化率为3.53%,有14株自交结实,经RT-PCR检测,T1代转基因玉米有9个株系为稳定遗传阳性株系.(2)在同一水分胁迫时间下,转基因玉米的叶片相对含水量、叶绿素含量、脯氨酸含量和SOD活性均高于非转基因玉米,而转基因玉米叶片的电导率、MDA含量均低于非转基因玉米.在60 h水分胁迫处理下,转基因玉米叶片相对含水量、叶绿素含量、脯氨酸含量和SOD活性比非转基因玉米上升8.16%、20.02%、32.21%、22.77%,而转基因玉米叶片的电导率、MDA含量比非转基因玉米下降14.38%、29.41%.研究表明,通过导入SAMS基因,可以提高玉米的抗旱性.
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