氯化镧对玉米幼苗抗盐性的影响

Effect of Lanthanum Chloride on Salt Tolerance of Maize Seedlings

采用溶液培养法研究氯化镧对盐胁迫下新单29幼苗根和叶抗氧化特性、渗透调节物质和单株生物量的影响。结果表明,10μmol/L LaCl3显著增加盐胁迫下叶片抗坏血酸过氧化物酶（APX）、谷胱甘肽还原酶（GR）活性、还原型抗坏血酸（AsA）质量摩尔浓度及根系过氧化氢酶（CAT）、GR和脱氢抗坏血酸还原酶（DHAR）活性及AsA质量摩尔浓度;30μmol/L LaCl3显著增加盐胁迫下叶片超氧化物歧化酶（SOD）、CAT、APX和GR活性、AsA质量摩尔浓度、脯氨酸质量分数及根系GR、DHAR活性、AsA质量摩尔浓度与可溶性糖质量分数;60μmol/L LaCl3显著增加盐胁迫下叶片SOD、CAT、APX和GR活性、AsA质量摩尔浓度、脯氨酸质量分数及根系DHAR活性和AsA质量摩尔浓度;90μmol/L LaCl3仅造成盐胁迫下叶片脯氨酸质量分数、根系DHAR活性及根叶AsA质量摩尔浓度显著增加。10-60μmol/L LaCl3均显著降低盐胁迫下根系和叶片丙二醛（MDA）质量摩尔浓度,从而显著增加单株生物量。90μmol/L LaCl3却显著增加盐胁迫下根系MDA质量摩尔浓度,使单株生物量下降。说明,外源施加低浓度的氯化镧可显著增强新单29幼苗的抗盐性,高浓度则不利于抗盐性的提高。

For providing basis for application of lanthanum chloride in production of maize,the effect of lanthanum chloride on antioxidant properties,osmoregulation substances of the leaves and roots and the biomass per plant of Xindan29 seedling were investigated under salt stress.The results showed that 10μmol/L LaCl3 could increase the activities of ascorbate peroxidase（APX）,glutathione reductase（GR）and reduced ascorbate（AsA）molalities in leaves and the activities of catalase（CAT）,GR and dehydroascorbate reductase（DHAR）and AsA molalities in roots under salt stress.30μmol/L LaCl3 could increase activities of superoxide dismutase（SOD）,CAT,APX and GR,AsA molalities and the mass fraction of proline in leaves,as well as the activities of GR and DHAR,AsA molalities and mass fraction of soluble sugar in root.60μmol/L LaCl3 could increase the activities of SOD,CAT,APX and GR,AsA molalities and the mass fraction of proline in leaves,and DHAR activity and AsA molalities in root.90μmol/L LaCl3 could increase the mass fraction of proline in leaves,DHAR activity in roots and AsA molalities in leaves and root.10-60μmol/L LaCl3 significantlyreduced the malondialdehyde（MDA）molalities in leaves and roots,and significantly increased biomass per plant.However,90μmol/L LaCl3 significantly increased MDA molalities in roots and reduced the biomass per plant.In conclusion,low concentration of lanthanum chloride can enhance salt tolerance,and high concentration of lanthanum chloride is not good for increasing salt tolerance of Xindan29.