Abstract:

【Objective】 Amaranth (Amaranthus mangostanus L.) is widely distributed in China and China has abundant varieties, it can be served as a candidate of cadmium hyperaccumulators for phytoremediation by screening of amaranth cultivars which is tolerant to cadmium. 【Method】 To obtain cadmium hyper-accumulator, Cd uptake in 23 amaranth cultivars from different ecological regions was investigated under hydroponic culture condition. Meanwhile, a pot experiment was established to probe phytoremediation potentiality of Cd contaminated soil by amaranth. Three treatments (Cd 5, 10 and 25 mg?kg-1) were conducted using to red soil, yellow brown soil and vegetable soil. 【Result】 The results showed that under hydroponic culture with Cd 3 mg?L-1, the cadmium concentration in the shoots of the cultivar Tianxingmi reached 260 mg?kg-1, and its total cadmium uptake was the highest among various cultivars. In the treatment of Cd 25 mg?kg-1, the cadmium concentration in the shoots of the cultivar Tianxingmi reached 212 mg?kg-1, while the bioaccumulation factor and shoot purification rate reached 8.50 and 3.8%, respectively. Further, the total biomass and shoot biomass were not decreased significantly in all Cd treatments. 【Conclusion】 These results suggested that cultivar Tianxingmi is a typical Cd hyperaccumulator, and can be used in phytoremediation of Cd contaminated soil.

Key words: amaranth, cadmium, hyperaccumulation, phytoremediation