The toxicity of Cu on the seedlings of a mangrove (Kandelia candel) in the presence of NaCl

Abstract

For the growth of a mangrove, Kandelia candel, sodium chloride was shown to be physiologically necessary, and lack of NaCl and high dose of Cu were considered as stresses. On the other hand, chloride salinity promotes complex formation of Cu in nutrient solutions, which may dramatically affect metal activity and metal uptake. Hydroponic experiment was conducted to evaluate the effect of combination of Cu and NaCl on the growth of K candel. The effect of combination of non-salt and Cu exhibited slight to remarkable synergistic on the growth of K candel roots and leaves. While the concentration of Cu increased significantly in root with increasing Cu in culture media (especially in the treatment without NaCl), the concentration of Cu increased in leaves only in high doses. However, the increase of cations’ concentration in both root and leaves is not significantly correlated to total cations’ uptake. The salinity of sodium chloride acts not only the physiological requirement but also causes the interaction with Cu.