Hyperaccumulator

Hyperaccumulator species are able to accumulate higher metal concentrations in their shoots than surrounding nonaccumulator plants, even from soils containing nonphytotoxic background levels of metals [35-37].

Also, the progress of constructing ideal hyperaccumulators by using biological technologies is slow.

To date, over 400 species have been identified as hyperaccumulators, with this number increasing continuously as new species are identified (Baker et al., 2000).