Phytoextraction potential of six plant species grown in multimetal contaminated soil

A pot experiment was conducted to compare the phytoextraction potential of six plant species (Arabidopsis thaliana, Brassica juncea, Crotalaria juncea, Cynodon dactylon, Parthenium integrifolium and Phragmitis communis) for Zn, Ni, Cr and Cd removal by growing on multimetal contaminated soil. The results revealed that metal accumulation was plant specific. A. thaliana accumulated maximum Zn and Cd, whereas B. juncea and C. dactylon accumulated Ni and Cr in their shoots, respectively. B. juncea exceeded the Ni hyperaccumulation limit and accumulated 3916 mgkg-1 dry wt. The remediation factor for Zn and Cd was higher in A. thaliana, B. juncea and C. juncea, whereas it was higher for Ni in B. juncea. A. thaliana exhibited the maximum bioconcentration factor (BCF) for Zn and Cd whereas B. juncea showed for Ni and C. dactylon for Cr. The value of the translocation factor (TF) was1 for all metals in all plant species, except C. dactylon for Zn. The maximum TF value for Cd and Zn was recorded in B. juncea, for Ni in A. thaliana and for Cr in C. dactylon. Relatively higher metal content was observed in a CaCl2 extract than a natural soil solution. However, the available metal content in the soil solution tended to decrease at successive suction times.