The influence of duckweed species diversity on ecophysiological tolerance to copper exposure.

摘要: Abstract In excess, copper is toxic to plants. the plants, Landoltia punctata and Lemna minor grown in mixed monoculture, effects of exposure varying concentrations (0.01, 0.1, 0.5 1 mg L−1 Cu) for seven days were assessed by measuring changes chlorophyll, protein malondialdehyde (MDA) content, catalase (CAT), superoxide dismutase (SOD) ascorbate peroxidase (APX) activity. According results, Cu levels plants increased with increasing concentration. The level photosynthetic pigments crude proteins decreased only upon high concentrations. However, starch content increased. These results suggested a stress alleviation that was possibly result antioxidants such as CAT SOD, activities which levels. APX activity L. punctata, but minor, under monoculture or culture conditions. addition, duckweed exhibited antioxidant enzyme provide resistance moderate As concentration increased, limited uptake avoid toxicity.