苋菜活性氧代谢对铅胁迫的响应  

Effects of Lead Stress on Active Oxygen Metabolism in Amaranth

作　　者：杨敏文[1] 柯世省[1] 

机构地区：[1]台州学院,浙江临海317000

出　　处：《安徽农业科学》2008年第30期13029-13031,13035,共4页Journal of Anhui Agricultural Sciences

基　　金：浙江省自然科学基金资助项目(Y504256)

摘　　要：[目的]了解铅对植物生长的抑制作用。[方法]以苋菜品种一点红为试材,采用盆栽试验,以醋酸铅配制土壤铅含量分别为0.1、0.2、0.4、0.8和1.6 mmol/kg干土,不加铅为对照,研究铅处理对苋菜生长、铅积累和活性氧代谢的影响。[结果]播种45 d后,铅胁迫(>0.4 mmol/kg)下苋菜的生长受到明显抑制,其中根受到的抑制程度最高。铅胁迫明显增加了苋菜器官中铅的含量,并主要积累在根部。随着铅处理浓度的增加,成熟叶超氧阴离子产生速率加快,过氧化氢含量、SOD和POD活性增加,CAT和APX活性降低,氧阴离子产生速率、过氧化氢含量、MDA含量和细胞电解质渗漏增加。[结论]铅胁迫引起苋菜活性氧代谢失衡,过氧化作用加剧,导致植物生长受阻。[Objective] The aim was to study the inhibition effects of lead （Pb） on plant growth. [Method] In the pot experiment,with amaranth variety Yiping-red as test material, Pb in the form of Pb（CH3COO）2 was added to the soil for a series of soil Pb levels of 0.1,0.2,0.4,0.8 and 1.6 mmol/kg soil （dry weight）, and treatment without adding Pb was regarded as control. The effects of lead treatment on the growth, lead accumulation and active oxygen metabolis,n of amaranth were studied. [Result] Forty-five days after amaranth seeds being sown,excess Pb （ 〉 0.4mmol/kg） significantly reduced the dry weight of leaves, stews and roots of amaranth with the maxhnum depression in the roots, and significantly promoted Pb accumulation in amaranth organs. Moreover Pb was sequestered primarily in the roots. Along with Pb levels increased,supemxide dismutase （SOD） and pemxidase （POD） activities in the mature leaves increased significantly, while catalase （CAT） and ascorbate pemxidase （APX） activities decreased, accompanied by the increase in the contents of hydrogen peroxide （ H2O2 ）, supemxide anion （ O2·^- ）, malondiadehyde （MDA）, and electrolyte leakage. [ Conclusion ] As a result of unbalance of active oxygen metabolism under Pb stress, pemxidization was aggravated. Finally, the growth of amaranth was significantly inhibited.

关 键 词：铅胁迫 生长分析 活性氧 抗氧化酶活性 苋菜 

分 类 号：S311[农业科学—作物栽培与耕作技术]