Phytoremediation of Heavy Metals via Transgenic Plants——Mechanisms and Applications

Phytoremediation of contaminated environments has the advantages of low cost and does not cause secondary pollutions. Finding hyperaccumulating plants from wild habitats has proven to be difficult and is limited by low biomass, short growth season and geographical distribution of the plants. It is very promising to use transgenic plants for phytoremediation and has recently made great progress in this area. High level expression of transgenes in plants stimulates absorption, translocation and degradation of contaminated substances, thus increases the remediation efficiency. In addition, transgenic plants have been used as model systems to study the mechanisms of phytoremediation. This paper outlines the mechanisms, status and problems of phytoremediation via transgenic plants, with heavy metal detoxification and tolerance of As, Hg and Pb as examples. The ways to increase phytoremediation efficiency with other remediation methods are also discussed.