中文摘要：

胆碱单加氧酶（choline monooxygenase,CMO）是植物甜菜碱合成过程中重要的限速酶。为探讨转北美海蓬子（Salicornia bigelovii）cmo基因烟草（Nicotiana tabacum）在耐盐基因工程中的应用,利用基础质粒p CAMBIA1300UR构建p CAMBIA1300UR-cmo植物表达载体,通过电击法将重组质粒导入农杆菌（Agrobacterium tumefaciens）EHA105中,并采用农杆菌介导的叶盘转化法转入烟草,经抗生素筛选、PCR和q RT-PCR检测后,对阳性烟草植株进行耐盐性鉴定。结果表明,北美海蓬子cmo基因在烟草中具有80%的转化效率,在200 mmol/L盐胁迫下,转基因植株的超氧化物歧化酶（superoxide dismutase,SOD）、过氧化物酶（peroxidase,POD）、过氧化氢酶（catalase,CAT）及脯氨酸（proline,PRO）含量明显高于非转基因的烟草植株,而丙二醛（malondialdehyde,MDA）含量和过氧化氢（hydrogen peroxide,H2O2）含量则低于非转基因组。结果表明,cmo基因的转化提高了烟草的耐盐性,为进一步阐明cmo基因在植物体内的甜菜碱合成代谢途径、抗逆调控机制及培育耐盐植物新品种提供基因资源库和理论参考。

英文摘要：

Choline monooxygenase（CMO） is an important rate-limiting enzyme in the biosynthesis of betaine.To investigate the application that transform cmo gene in Salicornia bigelovii to the Nicotiana tabacum,basic plasmid p CAMBIA1300 UR was used to construct the expression vector p CAMBIA1300UR-cmo.Then the reconstructed expression vector was mediated into agrobacterium EHA105 by electric shock.So that the recombinant vector were introduced into the tobacco genome by Agrobacterium tumefaciens mediated transformation.Antibiotics（kanamycin） screening,PCR and q RT-PCR were all used to confirm the success of transformation.After treated with different concentrative Na Cl for 10 d,the transgenic tobacco was searched for the evidence of salt tolerance.The results showed that the transformative efficiency of cmo were estimated up to 80%.When treated by the condition of 200 mmol/L of Na Cl,the activity of superoxide dismutase（SOD）,peroxidase（POD）,catalase（CAT） and proline（PRO） of transgenic tobacco were stronger obviously than that in the non-transgenic plants except the content of MDA and H2O2.So the cmo gene could improve thesalt tolerance in the tobacco plants.The study laid the foundation of finding and exploitation of resistant genes from stress-tolerant plants.