Hyperaccumulation of Cd by Rorippa globosa (Turcz.) Thell. from soil enriched with different Cd compounds, and impact of soil amendment with glutathione (GSH) on the hyperaccumulation efficiency.

Rorippa globosa (Turcz.) Thell. is known as Cd hyperaccumulator, however neither hyperaccumulation nature, nor affecting factors like the effect of Cd compounds entering soil from different sources, or of specific soil amendments, are not yet satisfactorily clarified. In the pot culture experiment, Cd accumulation by R. globosa from soils spiked with 3 and 9 mg Cd kg ^-1 in the form of Cd(NO ₃ ) ₂ , CdCl ₂ , CdBr ₂ , CdI ₂ , CdSO ₄ , CdF ₂ , Cd(OH) ₂ , CdCO ₃ , Cd ₃ (PO ₄ ) ₂ , CdS and effect of soil amendment with glutathione (GSH) were investigated. Accumulation capacity of R. globosa for Cd appeared to reflect its extractability in soils and was about two-fold bigger for high soluble compounds than for low-soluble ones. At that, the differences between the accumulation of Cd originating from high soluble compound group did not exceed 20%, while the differences within the low soluble compound group were insignificant (p < 0.05). The analysis of Cd uptake, uptake factor (UF), enrichment factor (EF) and translocation factor (TF) patterns revealed that Cd hyperaccumulating properties of R. globosa are based on the high water/nutrients demand and strong tolerance to Cd, although weak protection against Cd uptake by root system was also observed. Amendment with GSH enhanced Cd availability to plant and its uptake from soil, but exerted no effect on Cd translocation in plants. In the light of the results, the use of R. globosa for phytoremediation of moderately polluted agricultural lands as forecrop or aftercrop, and the GSH-assisted phytoremediation of highly polluted post-industrial sites seem to be viable options.
(Copyright © 2019 Elsevier Ltd. All rights reserved.)