Uptake and distribution of selenium in different fern species.

There has been an interest in using hyperaccumulating plants for the removal of heavy metals and metalloids. High selenium (Se) concentrations in the environment are detrimental to animals, humans, and sustainable agriculture, yet selenium is also an essential nutrient for humans. This experiment was conducted to screen fern plants for their potential to accumulate selenium. Eleven fern species, Pteris vittata, P. quadriaurita, P. dentata, P. ensiformis, P. cretica, Dryopteris erythrosora, Didymochlaena truncatula, Adiantum hispidulum, Actiniopteris radiata, Davallia griffithiana, and Cyrtomium fulcatum, were grown under hydroponic conditions for one week at 20 mg L(-1) selenate or selenite. Root Se concentrations reached 245-731 and 516-1082 mg kg(-1) when treated with selenate and selenite, respectively. The corresponding numbers in the fronds were 153-745 and 74-1,028 mg kg(-1) with no visible toxicity symptoms. Only three fern species were able to accumulate more Se in the fronds than the roots, which were D. griffithiana when treated with selenate, P. vittata when treated with selenite, and A. radiata regardless of the forms of Se. A. radiata was the best species overall for Se accumulation. More research is needed to further determine the potential of the fern species identified in this study for phytoremediation of the Se contaminated soils and water.