Using Elevated Carbon Dioxide to Enhance Copper Accumulation in Pteridium Revolutum, a Copper-Tolerant Plant, Under Experimental Conditions

Abstract

In our survey in the copper (Cu) mining area of China, a sun fern (Pteridium revolutum) was found to accumulate 30–567 mg Cu kg⁻¹ DW (33 samples) in its fronds with a large frond biomass. Cu translocation factors in the plants varied from 0.09 to 3.88. In a greenhouse pot experiment, the effect of an elevated CO₂ concentration (700 μL L⁻¹) on Cu accumulation in plants was studied using three fern species (P. revolutum, Pteridium aquilinum, and Pteris vittata) grown in the Cu-contaminated soil. P. revolutum showed a higher Cu tolerance but its Cu translocation factor was lower than 1. At the elevated CO₂ concentration, frond biomass of all species was significantly increased, as was the total Cu content in the fronds of P. revolutum and P. aquilinum. Our study suggests that P. revolutum could serve as a good candidate for phytoextraction of Cu-contaminated soils and that doubling the ambient CO₂ concentration will facilitate its use in phytoextraction.

KEY WORDS:

• accumulation
• copper (Cu)
• elevated CO₂
• Pteridium revolutum
• phytoextraction

ACKNOWLEDGEMENTS

This research work was financially supported by the National Natural Science Foundation of China under grants 20477035 and NKBRSFG 1999011808. The authors would like to thank Prof. Jay Gan, University of California Riverside, for reviewing this manuscript.