【作者】 徐彩平；

【导师】 陈颖；

【作者基本信息】 南京林业大学 ， 植物学， 2012， 硕士

【摘要】 本研究以美洲黑杨杂种优良无性系南林895杨(Populus×euramericana cv.Nanlin895)组培苗为研究对象，进行NaCl胁迫处理。通过调查组培苗的生长情况、测定膜透性、渗透调节物质的含量和相关酶的活性等，得到以下主要结论：1.南林895杨具有一定的耐盐性，但在100mmol/L NaCl处理下，组培苗的生长受到明显的抑制作用，株高和根长均下降，叶片的黄化和脱落现象加剧。叶片的相对电导率增加，光合色素含量下降。叶片受盐害现象比较严重，根受到的盐害症状较轻。2.随盐浓度的增加，南林895杨组培苗叶片和根中的脯氨酸含量增加。根中的可溶性糖含量持续上升，叶片中的可溶性糖含量下降。叶片和根中可溶性蛋白的含量均下降。无机盐离子Na+的含量持续上升，根中的变化小于叶片中的变化。无机盐离子K+在各部位中呈下降趋势。叶片主要是通过积累脯氨酸和无机盐离子Na+，根主要是通过积累脯氨酸和可溶性糖共同维持体内的渗透势。3.随盐浓度的增加，南林895杨组培苗叶片和根中超氧化物歧化酶(SOD)的活性是先升高后降低，100mmol/L NaCl处理的SOD活性低于对照活性。叶片和根中的过氧化物酶(POD)活性均上升。50mmol/L NaCl处理的叶片中的过氧化氢酶(CAT)活性高于对照水平，其他处理的叶片和根中的CAT活性均低于对照水平。根中的抗坏血酸过氧化物酶(APX)活性持续上升，叶片中的APX是先上升后下降。根中的谷胱甘肽还原酶(GR)活性持续上升，叶片中的GR活性持续下降。丙二醛(MDA)含量持续上升。SOD、POD、APX和GR在根中作用比较大，SOD、APX、POD和CAT在叶片作用比较大。但高盐下，一些酶的活性受到了影响，仅有叶片和根中POD、根中APX和GR的活性比较强。4.南林895杨组培苗叶片中的蛋白表达高于根中的蛋白表达。NaCl处理后，蛋白表达均上升，有新的特异蛋白的产生。高分子区域表现为48KD的蛋白条带，低分子区域主要是20KD和14KD，这些蛋白主要集中在pI4~7。更多还原

【Abstract】 In this study, Populus×euramericana cv.Nanlin895tissue culture plantlets are experimentmaterial. Growth condition, membrane permeability, the content of osmotic adjustmentsubstances and the activity of enzymes were tested after NaCl stress. The result showed asfollows:1.‘Nanlin895’ tissue culture plantlets could grow after100mmol/L NaCl stress, but thegrowth was significantly inhibited. Plant height and root length were decreased. Leaves wereseriously yellowing and shedding. The relative conductivity was increased and photosyntheticpigments content were decreased in leaves. Leaves were affected more seriously than roots.2. With the increasing of salt concentration, the proline content were increased in ‘Nanlin895’ tissue culture plantlets leaves and roots. The content of soluble sugar were increased inroots and decreased in leaves continuously. The soluble protein were both decreased in rootsand leaves. The content of Na+were continuously increased and the change in leaves wasgreater than roots. The content of K+were decreased in every organ. In short, leaves weremainly accumulate proline and Na+, and roots were accumulate proline and soluble sugar inmaintaining osmotic potential.3. With the increasing of salt concentration, the activity of superoxide dismutase(SOD)were increased firstly, and then decreased in plantlets leaves and roots. Under100mmol/L NaClstress, the activity of SOD were lower than control. The activity of peroxidase(POD) were bothincreased in leaves and roots. Under50mmol/L NaCl stress, the activity of catalase(CAT) werehigher than control in leaves. In other tests, the activity of CAT were lower than control inleaves and roots. The activity of acorbate peroxidase(APX) were continuously increased inroots. In leaves, they were increased firstly, and then decreased. The activity of glutathionereductase(GR) were increased in roots and decreased in leaves continuously. The content ofmalondiadehyde(MDA) were continuously increased. SOD、POD、APX and GR played moreroles in roots. SOD、APX、POD and CAT played more roles in leaves. But high salt stressdestroyed some enzymes’ activity. Only the activity of POD in leaves and roots, APX and GRin roots were still higher.4. The protein expression in leaves was higher than roots. After NaCl stress, the proteinexpression were all rose and some specific stress-up-regulate protein appeared. High molecularweight regions were48kilodalton (KD). Low molecular weight regions were mainly20KD and14KD. They were mainly focused on isoelectric point(pI)4~7.更多还原