砷胁迫对桉树抗氧化酶活性的影响  

Effects of Arsenic Stress on Activities of Antioxidant Enzymes of Eucalyptus

作　　者：蒙敏[1] 黄雪芬[1] 李磊[1] 罗宇晨 王维生[1] 

机构地区：[1]广西大学环境学院,南宁530004

出　　处：《基因组学与应用生物学》2017年第12期5289-5295,共7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：通过水培实验,研究了砷胁迫对桉树根和叶的生物量,对砷、叶绿素和丙二醛(MDA)含量,以及对超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活性的影响,讨论了桉树抗氧化酶系统在砷胁迫造成的氧化损伤中的作用。实验结果表明桉树叶的砷含量随砷胁迫浓度的增加而增加,根的砷含量高于叶。在低浓度砷(5 mg/L和10 mg/L)胁迫时,生物量及根和叶中MDA含量较对照无显著性差异,根中SOD、CAT和POD的活性增加,过氧化物的积累减缓。在高浓度砷(20 mg/L和30 mg/L)胁迫时,生物量和叶绿素的含量减少,SOD、CAT和POD活性降低,MDA含量显著性增加,桉树遭受较强的氧化损伤。结果表明,在低浓度砷胁迫时,抗氧化酶系统对砷胁迫造成的氧化损伤有较好的缓解作用;在高浓度砷胁迫时,大量过氧化物积累,抗氧化酶系统对氧化损伤的缓解作用大大降低。The effects of arsenic（As） stress on the biomass of roots and leaves of Eucalyptus, on the contents of As,chlorophyll and malondialdehyde（MDA）, and on the activities of superoxide dismutase（SOD）, catalase（CAT） and peroxidase（POD） were studied by hydroponic experiment, the role of antioxidant enzyme system of Eucalyptus in the oxidative damage caused by As stress was discussed. The experimental results showed that the contents of As in the leaves of Eucalyptus increased with the increasing concentrations of As stress, the contents of As in roots were higher than those in leaves. At low concentrations of As stress（5 mg/L and 10 mg/L）, the biomass and the contents of MDA in roots and leaves had insignificant differences compared to the controls, the activities of SOD, CAT and POD in roots increased, the accumulation of hyperoxide alleviated. At high concentrations of As stress（20 mg/L and30 mg/L）, the biomass and the contents of chlorophyll decreased, the activities of SOD, CAT and POD declined, the contents of MDA significantly increased, Eucalyptus strongly sufferd from the oxidative damage. The results showed that at low concentrations of As stress, the antioxidant enzyme system had good alleviating effects on the oxidative damage caused by As stress, and at high concentrations of As stress, much hyperoxide was accumulated, the alleviating effects of the antioxidant enzyme system on the oxidative damage were deeply reduced.

关 键 词：砷 桉树 叶绿素 丙二醛 抗氧化酶 

分 类 号：S792.39[农业科学—林木遗传育种]