镧浸种对盐胁迫下小麦幼苗生长及其生理特征的影响

通过水培方式研究了0、25、50和100 mg/L硝酸镧浸种对盐胁迫条件下小麦品种临抗11和临优2069根系及幼苗生长的影响.结果表明:(1)与对照组相比,盐胁迫处理小麦幼苗植株矮,根系短,叶片叶绿素含量、根系活性吸收面积以及SOD和CAT活性明显降低,叶片MDA与Pro含量水平显著上升;在钠离子浓度相同的情况下,Na2CO3对小麦生长的影响大于NaCl.(2)适当浓度硝酸镧浸种处理增加了盐胁迫下小麦幼苗的株高、总根长、根系活性吸收面积及SOD和CAT活性,且各指标在盐胁迫下增加幅度高于正常水分处理.(3)2个小麦品种对镧处理的敏感程度存在差异,不同小麦品种及不同盐胁迫下最适的镧浸种浓度不同.研究发现,适当浓度镧浸种能有效缓解盐胁迫对小麦幼苗的伤害,具有显著促进小麦根系生长、培育壮苗的作用.

Effects of Lanthanum on the Growth and Physiological Characteristics of Wheat Seedling under Salt Stress

An experiment using NaCl and Na2CO3 to induce salt stresses was carried out to evaluate the effects of seed soaking with different concentration of lanthanum(0,25,50 and 100 mg/L) on the seedling and root growth of wheat(cv.Linkang No.11 and cv.Linyou No.2069).The result showed that:(1) comparing with the control group,the wheat seedling under different salt stress has short height and short root length.And chlorophyll content,root vigor,CAT(catalase) and SOD(superoxide dismutase) activities also decreased drastically.The MDA and Pro content of leaf increased significantly at the same time.The intensity of damage was promoted with the increasing of the salt concentrations.Although the growth of wheat could be inhibited by both NaCl and Na2CO3 stresses,the extent of inhibition resulted from Na2CO3 stresses was greater than that from NaCl stress.(2)Seed soaking with the optimum concentration of lanthanum increased the total root length,leaf area,root vigor and the activity of SOD and CAT,and this increase under salt stresses was remarkably higher than that under normal condition.Therefore,the detrimental effects resulting from the salt stress were decreased.(3)The response to soaking seeds with lanthanum was different between wheat varieties,and the optimum concentration of lanthanum was different among both cultivars and salts concentration.All in all,soaking seeds with optimum concentration of lanthanum could play an important role in raising healthy wheat seedlings.