锌胁迫对桉树巯基物质含量及抗氧化酶活性的影响  

Effects of Zinc Stress on the Contents of Sulfhydryl Compounds and the Activities of Antioxidant Enzymes in Eucalyptus

作　　者：李磊 罗浚凤 谭琳山 王维生 Li Lei;Luo Junfeng;Tan Linshan;Wang Weisheng(College of Resources,Environment and Materials,Guangxi University,Nanning,530004)

机构地区：[1]广西大学资源环境与材料学院,南宁530004

出　　处：《基因组学与应用生物学》2020年第2期693-698,共6页Genomics and Applied Biology

基　　金：国家自然科学基金项目(41263007);广西自然科学基金项目(2012GXNSFDA053023)共同资助。

摘　　要：通过桉树的水培实验,测定了不同浓度Zn胁迫下桉树的生物量,根和叶中Zn、巯基物质(非蛋白巯基,谷胱甘肽和植物络合素)和丙二醛(MDA)的含量,以及根中抗氧化酶的活性。从巯基物质含量和抗氧化酶活性的角度,探讨了桉树抵御Zn胁迫造成氧化性伤害的机制。实验结果表明,Zn浓度较低(20 mg/L和40 mg/L)时,根中MDA含量非显著性增加,抗氧化酶超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的活性上升,叶中巯基物质含量非显著性增加。Zn浓度较高(120 mg/L和140 mg/L)时,根中MDA含量显著性增加,SOD、POD和CAT的活性下降,叶中巯基物质含量显著性增加。因此,低浓度Zn胁迫时,桉树中巯基物质和抗氧化酶系统对氧化性伤害有较好的缓解作用;高浓度Zn胁迫时,大量过氧化物积累,桉树中巯基物质和抗氧化酶系统对氧化损伤的缓解作用降低。Through hydroponic experiments of eucalyptus,the biomass of eucalyptus,the contents of Zn,sulfhydryl compounds(non-protein thiol peptides,glutathion and phytochelatins)and malondialdehyde(MDA)in the roots and leaves of eucalyptus,and the activities of antioxidant enzymes in the roots of eucalyptus were determined at different concentrations of As stress.The mechanism of eucalyptus resistance to the oxidative damage caused by Zn stress was discussed from the perspectives of the contents of sulfhydryl compounds and the activities of antioxidant enzymes.The experimental results showed that at low concentration of Zn(20 mg/L and40 mg/L)the content of MDA in root insignificantly increased,the activities of antioxidant enzymes superoxide dismutase(SOD),peroxidase(POD)and catalase(CAT)increased,and the contents of sulfhydryl compounds in leaves insignificantly increased.At high concentration of Zn(120 mg/L and 140 mg/L)the content of MDA in root significantly increased,the activities of SOD,POD and CAT decreased and the contents of sulfhydryl compounds in leaves significantly increased.Therefore,at low concentration of Zn stress,the sulfhydryl compounds and the antioxidant enzyme systems in eucalyptus had better alleviating effects on the oxidative damage.And at high concentration of Zn stress,much hyperoxides were accumulated,the alleviating effects of the sulfhydryl compounds and the antioxidant enzyme systems on the oxidative damage were reduced.

关 键 词：桉树 锌 巯基物质 抗氧化酶 

分 类 号：S792.39[农业科学—林木遗传育种]