GROWTH AND ANTIOXIDATIVE RESPONSES TO EXCESS CADMIUM IN KENAF (Hibiscus cannabinus L)

In order to study the mechanisms responsible for cadmium (Cd) detoxification in Kenaf (Hibiscus cannabinus L), the growth and antioxidative responses of the plant grown on a Cd polluted soil were investigated. Kenaf seeds were grown in artificially contaminated soils containing increasing concentrations of Cd as CdCl sub(2) (0, 150, 300, 450 and 600 mg Cd kg super(-1)) for 14 weeks in a screenhouse. Growth parameters (plant height and stem girth), Cd concentration, oxidative lipid peroxidation, glutathione (GSH) content, activity of antioxidant enzymes, superoxide dis-mutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) were measured using established techniques. Cd inhibits growth as shown by decrease in plant height and stem girth at all concentrations used compared with control. Plant Cd concentrations increased with soil Cd concentrations, with maximum Cd uptake being 73.37 plus or minus 8.82 mg kg super(-1) dry weight at 600 mg Cd kg super(-1). The content of malondialdehyde (indication of lipid peroxidation) showed a significant (p