Rhizofiltration of Cadmium and Lead by Hairy Root Cultures of Brassica juncea L. and the Influence of the Metals on Antioxidative Enzymes

Plant hairy roots induced by Agrobacterium rhizogenes can be used as a model system to study the uptake of heavy metals and the influence of metals on the antioxidative enzymes. Hairy roots induced in Brassica juncea L. Czern and Coss. when used for remediation of cadmium and lead from solutions, 90% of Pb from solutions upto 1000?M and 60% of Cd from 1000?M solutions could be taken up within 2 hrs of treatment. Antioxidant enzymes are known to be important defence system of plants to metal stress and enhanced activity of catalase, superoxide dismutase and guiacol peroxidase enzymes was observed in hairy roots at high concentrations of Cd, while in the case of Pb, the increase in enzyme activity was seen only for catalase (CAT) and superoxide dismutase (SOD) and not for guiacol peroxidase.