Abstract: Cadmium (Cd) is one of the main pollution elements in China’s heavy metal contaminated soil. As a research focus and frontier field in remediation of environmental contamination, phytoremediation is a green technology which has various advantages and is incomparable to other traditional soil contamination remediation methods. In this study, taking Solanum nigrum L. as the hyperaccumulator, pilot scale Cd phytoremediation was conducted in a Cdcontaminated crop field, Shenyang for two years. Analysis of Cd content in soil before and after phytoremediation showed that Cd removal was obvious. The average reductions in Cd level in the surface soil were 6.3% in the preliminary trial (PT) in the first year and 16.8% in the repeated trial (RT) in the second year, respectively. In PT and RT, the removal rates of Cd were 50.6% and 49.5% in the 20-40 cm layer, and 73.5% and 53.9% in the 40-60 cm layer, and 80.7% or not detected in the 60-80 cm layer, respectively. Data suggested that the biomass of the S. nigrum correlated significantly with the total Cd content accumulated in plants. The result from these trials showed that suitable soil condition in the field promoted the production of plant biomass to improve the ability of hyperaccumulator S. nigrum for Cd uptake and transporting from soil. Our study indicated that it is suitable to remediate the Cd contamination in Cd mildlytomoderately polluted soil and realize the optimum cycle of agricultural production by phytoremediation technique.

Key words: shading, yellowing, tea plant, Huangjinya