桐花树幼苗叶片生理生态指标对气态汞胁迫的响应  

Physiological Response of Aegiceras corniculatum Leaves to Hg^0 Stress

作　　者：袁俊[1] 丁振华[1] 

机构地区：[1]厦门大学环境与生态学院,厦门361100

出　　处：《生态毒理学报》2016年第2期216-222,共7页Asian Journal of Ecotoxicology

基　　金：国家自然科学基金(No.41176090)

摘　　要：桐花树是我国主要的广布种红树植物,具有泌盐性。通过胁迫实验,研究桐花树幼苗叶片生理生态指标对气态单质汞(Hg0)胁迫的响应,以期了解红树植物吸收和富集气态汞的机制。结果表明:气态汞胁迫造成桐花树叶片可溶性糖含量、过氧化物酶(POD)活性下降;而丙二醛(MDA)、脯氨酸、超氧化物歧化酶(SOD)等指标上升;叶绿素含量、过氧化氢酶(CAT)活性出现先升高后降低的趋势,还原型谷胱甘肽(GSH)含量则先降低后升高。总之,虽然Hg0胁迫可增加桐花树幼苗叶的膜质过氧化程度,影响其生理代谢活动,但其叶片可通过调节抗氧化酶活性及还原型谷胱甘肽含量来提高自身抗氧化能力,进而提高对Hg0的抗性。As one of the main widespread mangrove plants in China, Aegiceras corniculatum can tolerate salt by excreting salt. Mangroves are facing more and more serious heavy metal pollution, especially the mercury contamination. To investigate the mechanism of mercury absorption and tolerance of mangrove, stress experiments were conducted with Aegiceras corniculatum seedlings under Hg0 stress. In this experiment, physiological characteristics such as the contents of chlorophyll, soluble sugars, malondialdehyde（ MDA）, proline（ Pro）, and reduced glutathione（GSH）, activities of superoxide dismutase（SOD）, peroxidase（POD） and catalase（CAT） of Aegiceras corniculatum seedlings＇ leaves were measured. Results showed as follows： the content of soluble sugars and the activity of POD gradually decreased under Hg0stress; while MDA content,Pro content and SOD activity significantly increased; the chlorophyll content and CAT activity increased firstly and then decreased, and on the contrary, the content of GSH decreased initially and then increased. The findings from above study demonstrate that although Hg0 tress can lead to damage of metabolism by causing membrane lipid peroxidation in seedlings ＇leaves, but the seedlings could change activities of the antioxidative enzymes and the content of GSH to enhance the antioxidant abilities, and then strengthenorganism resistance to mercury.

关 键 词：气态单质汞 桐花树 生理指标 抗性 

分 类 号：X171.5[环境科学与工程—环境科学]