Phytoremediation potential of Cd and Zn by wetland plants, Colocasia esculenta L Schott, Cyperus malaccensis Lam., and Typha angustifolia L grown in hydroponics

Cadmium and zinc phytoremediation potential of wetland plants, Colocasia esculenta, Cyperus malaccensis, and Typha angustifolia, was investigated. Plants were grown for 15 days in nutrient solutions containing various concentrations of Cd (0, 5, 10, 20, 50 mg l^-1) and Zn (0, 10, 20, 50, 100 mg I^-1). T. angustifolia was tolerant to both metals as indicated by high RGR when grown in 50 mg I^-1 Cd and 100 mg I^-1 Zn solutions. All these plants accumulated more metals in their underground parts and > 100 mg kg^-1 in their aboveground with TF values < 1. Only C. esculenta could be considered a Zn hyperaccumulator because it could concentrate > 10,000 mg kg^-1 in its aboveground parts with TF > 1. T angustifolia exhibited highest biomass production and highest Cd and Zn uptake, confirming that this plant is a suitable candidate for treating of Cd contaminated soil/sediments.