薇甘菊和飞机草抗氧化物和膜脂过氧化物对光照和土壤水分的响应  

EFFECTS OF IRRADIANCE AND SOIL MOISTURE ON ANTIOXIDANTS AND MEMBRANE LIPID PEROXIDATION PRODUCTS IN MIKANIA MICRANTHA AND CHROMOLAENA ODORATUM

作　　者：张玲玲[1] 孙芳芳[1,2] 温达志[1] 

机构地区：[1]中国科学院华南植物园,广州510650 [2]中国科学院研究生院,北京100049

出　　处：《植物生态学报》2009年第5期974-983,共10页Chinese Journal of Plant Ecology

基　　金：国家自然科学基金重点项目专题(30630015);华南植物园珠江三角洲城市生态与环境定位研究平台建设项目(200603)

摘　　要：田间温室控制条件下研究入侵杂草薇甘菊(Mikania micrantha)和飞机草(Chromolaena odoratum)在不同光照(高、中、低光照)和土壤水分(高、中、低水分含量)交互作用下,叶片超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性,脯氨酸(Pro)、谷胱甘肽(GSH)以及膜脂过氧化物丙二醛(MDA)含量的变化,探讨两种杂草对不同光照和土壤水分交互作用的生理适应性。结果表明:高光下低水处理的两种杂草MDA含量均显著高于全水处理,表现出明显的胁迫。此胁迫条件下薇甘菊通过迅速提高SOD和CAT活性,提高Pro和GSH含量来清除活性氧,维持代谢平衡,但不能在干旱条件下维持较长时间;飞机草的SOD活性、Pro和GSH含量也迅速提高,在高光缺水的适应性响应中起了重要作用,CAT则未能发挥保护作用。相对于其他光照,低光显著降低了薇甘菊的SOD、CAT活性和MDA含量,而对飞机草上述指标的影响较小,说明低光降低了两种杂草尤其是薇甘菊的抗氧化物代谢水平。Aims Our objective was to better understand physiological acclimation to varying light and soil water conditions by established seedlings of Mikania micrantha and Chromolaena odoratum to provide insight into the control of these invasive species. Methods Seedlings were grown under optimum light and water conditions for plant stability and then treated by three light （full,medium and low irradiance） and three soil water （full,medium and low water content） conditions in field glasshouses. We measured superoxide dismutase （SOD） and catalase （CAT） activities and proline （Pro）, glutathione （GSH） and malondialdehyde （MDA） contents in leaves and compared the two species. Important findings Under full irradiance, the MDA content of both species in the low soil water treatment was always significantly higher than in the full soil water treatment （p〈0.01）, indicating that drought stressed both species under high light. Both species developed mechanisms to scavenge the active oxygen. M. micrantha improved the SOD, CAT activities and the Pro and GSH contents, though the antioxidants could not sustain for a long time; C. odoratum showed similar trends in the measured anti- oxidants, except CAT was less responsive and Pro and GSH played important roles in acclimation to high light and drought. Relative to other irradiances, low light significantly reduced SOD and CAT activities and MDA contents in M. micrantha, but had less effect on those variables in C. odoratum, implying that low light reduced the antioxidants metabolism of both species, especially M. micrantha.

关 键 词：薇甘菊 飞机草 抗氧化物 SOD活性 MDA含量 

分 类 号：S451[农业科学—植物保护]