In-situ cadmium phytoremediation using Solanum nigrum L.: the bio-accumulation characteristics trail.

In this study, Solanum nigrum L. was used in-situ for Cdphytoremediation in Cd polluted soil on Shenyang Zhangshi Irrigation area (SZIA) in 2008. The performance of the plant over the whole growth stage was assessed. Results showed, during the whole experimental stage, the aboveground biomass of single Solanum nigrum L. grew by a factor of 190, from 1.6 +/- 0.4 g to 300.3 +/- 30.2 g with 141.2 times extracted Cd increase from 0.025 +/- 0.001 to 3.53 +/- 0.16 mg. Both the distribution of biomass and amount of extracted Cd in the above-ground part of the plant changed according to the growth of the plant. Particularly, the percentage of biomass and extracted Cd in the stem increased from 20% to 80% and from 11% to 69%, respectively. The bioconcentration factor and transfer factor both varied significantly during the growth of the plant and the lowest values were measured at the flowering stage (0.94 +/- 0.31 and 3.48 +/- 1.14 respectively). The results in this paper provide reference values for the future research on the application of Solanum nigrum L. in phytoremediation and on chemical or/and agricultural strategies for phytoextraction efficiency enhancement.