Effects of Cadmium and Copper on Growth Parameters of Hollyhock (Althea rosea L.)

Increasing levels of heavy metal compounds produced as the mining and industrial activities of human are the important source of environmental pollution. In urban areas, ornamental plants can be considered as a tool to remove these pollutants. However, the responses of this group of plants to high concentrations of these pollutants should be determined. This study was performed as a factorial experiment in a CRD. The treatments consisting of cadmium at four levels (0, 20, 40 or 80 mg kg-1 soil) and four doses of Cu (, 20, 40 or 80 mg kg-1 soil). One month after treating the soils inside the pots, hollyhock seedlings were transplanted. Plants were grown for a period of four months and then sampled for content of Cd, Cu, proline content, ion leakage, photosynthetic pigments and some growth parameters determination. The highest concentration of cadmium belonged to 20 and 4 mg kg-1 in the case of roots and to 80 mg kg-1 in the case of shoot parts. The highest values of Cu accumulation in both roots and shoot parts were obtained with application of the highest level of Cu. Increasing Cd and Cu levels, significantly increased proline content and ion leakage but decreased photosynthetic pigments. Generally, it can be suggested that hollyhock plant can be used as a phytoremediator to remove mild levels of Cd and Cu pollutions.