沙冬青(Ammopiptanthus mongolicus)是亚洲中部荒漠地区唯一的常绿阔叶灌木,本课题组已将其在天津引种栽培成功。为进一步了解生长素和氯化钙对沙冬青在盐胁迫下的缓解作用,用水培方法培养沙冬青幼苗,测定其在1.3%NaCl胁迫下经不同浓度的生长素和氯化钙处理后抗氧化酶活性、PSII光化学效率以及其它与植物抗性有关的生理指标的变化。结果表明,一定浓度的IBA和CaCl2处理可以促进盐胁迫下沙冬青幼苗的生长、提高叶绿素的含量、增强保护酶的活性、降低丙二醛含量,缓解了盐胁迫。但是当IBA、CaCl2浓度分别达到5和20mmol.L-1时则对沙冬青幼苗产生伤害。综合各项生理指标说明,CaCl对沙冬青盐胁迫的缓减作用要优于IBA。
Ammopiptanthus mongolicus,an endangered evergreen leguminous shrub,which is endemic to the semi-arid desert region of central Asia was successfully introduced in Tianjin by our team.In order to understand the mitigative effect of IBA and CaCl2 of A.mongolicus seedlings under salt stress,the seedlings were treated with 1.3% NaCl and different concentrations of IBA and CaCl2 under water culture.Antioxidant enzyme activities,photochemical efficiency of PSII and other related physiological index are measured and analyzed.The results showed that several treatments improved the growth of A.mongolicus seedlings;they were also helpful to increase the content of chlorophyll,the activity of antioxidant enzyme.It was also found that the application of IBA and CaCl2 could decrease the accumulation of malondialdehyde(MDA).Therefore,the injuries induced by the salt stress were mitigated and salt resistance of A.mongolicus was raised by the low concentration of IBA and CaCl2.When the concentration of IBA and CaCl2 reached 5 and 20 mmol·L-1,respectively,the seedlings growth were inhibited.The application effect of CaCl2 is better than IBA.