Improved understanding of hyperaccumulation yields commercial phytoextraction and phytomining technologies
Rufus L Chaney1, J Scott Angle, C Leigh Broadhurst
1USDA-ARS-Environmental Management and By-Product Utilization Lab., Beltsville, MD 20705, USA. Rufus.Chaney@ars.usda.gov
Journal of Environmental Quality
|September 4, 2007
Summary
Phytoextraction uses hyperaccumulator plants to remove soil elements. Alyssum species show commercial success in nickel phytomining, while Thlaspi caerulescens is effective for cadmium removal.
Area of Science:
- Environmental Science
- Plant Biology
- Biotechnology
Background:
- Phytoextraction utilizes hyperaccumulator plants for soil remediation.
- Research has explored various elements and plant species, with mixed success.
- Commercial phytomining for nickel has been established using Alyssum species.
Purpose of the Study:
- Review progress in phytoextraction technologies.
- Highlight the role of hyperaccumulator plants.
- Discuss specific examples like nickel and cadmium phytoextraction.
Main Methods:
- Review of existing research on phytoextraction.
- Detailed examination of nickel phytoextraction by Alyssum species.
- Analysis of cadmium phytoextraction challenges and successful species.
Main Results:
- Nickel phytoextraction by Alyssum is a commercialized phytomining technology.
- Thlaspi caerulescens effectively phytoextracts cadmium from soils with high zinc levels.
- Transgenic plants show promise for mercury phytoextraction, but broader success is distant.
Conclusions:
- Hyperaccumulator plants are crucial for effective phytoextraction.
- Commercial viability can be achieved through phytomining and valuable biomass production.
- Further research is needed to clone genes for broad hyperaccumulation capabilities.
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