Photosynthesis and growth responses of giant reed ( Arundo donax L.) to the heavy metals Cd and Ni

Giant reed ( Arundo donax L.) was grown on surface soil and irrigated with mixed heavy metal solutions of Cd(II) and Ni(II) to study the impact of these heavy metals on its growth and photosynthesis. The tested concentrations were 5, 50, and 100 ppm for each heavy metal against the control and resulted in high cadmium and nickel (DTPA extractable) concentrations in the top zone of the pot soil. The examined parameters, namely, stem height and diameter, number of nodes, fresh and dry weight of leaves, and net photosynthesis (Pn) were not affected, indicating that plants tolerate the high concentrations of Cd and Ni. As giant reed plants are very promising energy plants, they can be cultivated in contaminated soils to provide biomass for energy production purposes.