Cadmium accumulation characteristics and removal potentials of high cadmium accumulating rice line grown in cadmium-contaminated soils.

Abstract

Phytoextraction is a promising technique to remove cadmium (Cd) from contaminated soils. In this research, the two different Cd accumulation rice lines of Lu527-8 (the high Cd accumulating rice line) and Lu527-4 (the normal rice line) were grown in soils with different Cd treatments (0, 5, 10, and 20mgkg(-1) soil) to evaluate Cd accumulation characteristics and Cd removal potentials. When the concentration of Cd in soil increased, Lu527-8 showed less symptoms of phytotoxicity when compared to Lu527-4. Furthermore, Lu527-8 demonstrated greater shoot Cd accumulation (321.17-964.95mgplant(-1)) than Lu527-4 (50.37-201.66μgplant(-1)) at the jointing and filling stages. The soil available Cd content of Lu527-8 significantly decreased by 26.92-38.97 and 27.77-63.44% at the jointing and filling stages, respectively. Meanwhile, the total Cd content in soil also reduced by 11.64-46.75 and 21.41-54.11% at jointing and filling stages, respectively. When the Cd concentration in soil was 20mgkg(-1), the Cd extraction rate in shoots of Lu527-8 reached 2.12 and 2.85% which increased 10.60 and 6.48 times compared with that of Lu527-4 at the jointing and filling stages, respectively. In conclusion, this study demonstrates that Lu527-8 shows great abilities of Cd accumulation and Cd removal potential from contaminated soils with different Cd treatments and it is a promising species for phytoextraction of Cd-contaminated soils.