Search

This study was set up to investigate interactions between Zn and Cd accumulation, and the potential defensive role of antioxidative enzymes in polymetallic hyperaccumulator Arabis paniculata Franch. Plants were exposed to 100, 2000 pM Zn, or 10, 250 pM Cd or the co-exposure of Zn and Cd in hydroponics for 10 d. Results showed that A. paniculata exhibited distinguished high accumulation and tolerance to both of Zn and Cd without biomass reduction in all treatments compared to the control. The dose-dependent and organ-specific of Zn and Cd accumulation in plants indicated that there might be common transportation or metalspecific pathway in A. paniculata. Besides, H2O2 accumulation was kept at a relative consistent and tolerable level where plant growth was not inhibited under Zn and Cd stress. While superoxide dismutase (SOD), catalase (CAT) and guaiacol peroxidase (GPX) did not respond to H2O2 savaging in plants, ascorbate peroxidase (APX) made major contribution to maintain the H2O2 homeostasis in A. paniculata. [ABSTRACT FROM AUTHOR]