Study on the Tolerance and Enrichment Characteristics of Cadmium of Sedum alfredii Hance under Solution Culture

[Objective]The research aimed to study the differences between the tolerance and enrichment characteristics of cadmium of different ecotype Sedum alfredii Hance.[Method]Taken two contrasting ecotypes(non-mined ecotype and mined ecotype) of S.alfredii Hance as materials,and the characteristics of plant growth and uptake of cadmium(Cd) were studied by hydroponic experiments.[Result]The results showed that the critical concentrations of external Cd for non-mined ecotype S.alfredii Hance and mined ecotype S.alfredii Hance were 100 and 400 μmol/L,respectively.The concentrations of Cd in non-mined ecotype S.alfredii Hance and mined ecotype S.alfredii Hance increased with the external Cd supply,and the maximum values were 493 mg/kg(DW) in leaf and 934 mg/kg(DW) in stem respectively for non-mined ecotype S.alfredii Hance,while the maximum Cd concentration in leaf and stem reached at 4 933 and 3 874 mg/kg(DW) for mined ecotype S.alfredii Hance.At the same level of Cd supply,Cd concentrations among various parts within each ecotype plants,the order rootstemleaf was recorded in non-mined ecotype S.alfredii Hance,whereas leaf stemroot was observed in mined ecotype S.alfredii Hance.[Conclusion]It is concluded that mined ecotype S.alfredii Hance has better ability to tolerate,uptake and transport Cd than non-mined ecotype S.alfredii Hance.