Chin J Plan Ecolo ›› 2009, Vol. 33 ›› Issue (5): 974-983.DOI: 10.3773/j.issn.1005-264x.2009.05.017

• Research Articles • Previous Articles     Next Articles

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

ZHANG Ling-Ling1; SUN Fang-Fang1, 2;WEN Da-Zhi1*   

  1. 1South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China;2Graduate University of the Chinese Academy of Sciences, Beijing 100049, China
  • Online:2009-09-30 Published:2009-09-30
  • Contact: WEN Da-Zhi

Abstract: 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 ac-tivities 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.