TY - JOUR ID - 10.1016/j.jes.2014.08.005 TI - Cadmium accumulation and tolerance of two castor cultivars in relation to antioxidant systems AU - Hanzhi Zhang AU - Qingjun Guo AU - Junxing Yang AU - Tongbin Chen AU - Guangxu Zhu AU - Marc Peters AU - Rongfei Wei AU - Liyan Tian AU - Chunyu Wang AU - Deyun Tan AU - Jie Ma AU - Gangming Wang and Yingxin Wan VL - 26 IS - 10 PB - SP - 2048 EP - 2055 PY - JF - Journal of Environmental Sciences JA - J. Environ. Sci. UR - http://www.jesc.ac.cn/jesc_en/ch/reader/view_abstract.aspx?file_no=2014261012&flag=1 KW - Cadmium;Castor;Antioxidant activity;Tolerance;Phytoremediation KW - Cadmium;Castor;Antioxidant activity;Tolerance;Phytoremediation AB - To investigate the effects of Cd on tolerance and antioxidant activities of castor, two different castor (Ricinus communis L.) cultivars (Zibo No. 5 and Zibo No. 8) were used for a hydroponic experiment (0, 1 and 2 mg/L Cd) and a pot experiment using Cd-contaminated soil (34 mg/kg) with the addition of ethylenedinitrilotetraacetic acid (EDTA). The results indicated that there were significant differences between the two cultivars with respect to Cd uptake in shoots (113-248 mg/kg for Zibo No. 5 and 130-288 mg/kg Zibo No. 8), biomass tolerance indexes (64.9%-74.6% for Zibo No. 5 and 80.1%-90.9% for Zibo No. 8) in the hydroponic experiment and survival rates (0% for Zibo No. 5 and 100% for Zibo No. 8) determined by the addition of EDTA in the pot experiment, suggesting that Zibo No. 8 has higher tolerance than Zibo No. 5. Moreover, the castor cultivars have low bioconcentration factors (4.80% for Zibo No. 5 and 5.43% for Zibo No. 8) and low translocation factors (<1%). Consequently, Zibo No. 8 can participate in Cd phytostabilization in highly Cd-polluted areas. The results indicated that glutathione (GSH) as a non-enzymatic antioxidant, and antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT) and guaiacol peroxidase (GPX), were cultivar- and dose-dependent. The higher tolerance of Zibo No. 8 compared with Zibo No. 5 can be attributed to the higher GSH levels in the root and higher GPX activity in the leaf. ER -