Comparative study of hyperaccumulation of nickel by alyssum murale s.l. populations from the ultramafics of serbia

Abstract

Ultramafic areas exist in large blocks or as small outcrops separated from other geological substrates in Serbia and host a certain number of facultative serpentinophytes. Among them is Alyssum murale Waldst & Kit. s.l., widespread species distributed in SE Europe and SW Asia and well known example of Ni hyperac-cumulators. The aims of the present study were to investigate the level of concentration of Ni (and some elements such as Fe, Mn, Zn, Cu, Ni, Cr, Pb, Co, and Cd) at several serpentine soils in Serbia and to determine the level of accumulation of these elements in roots, shoots, and leaves, with a focus on Ni. The maximum available concentrations of metals in soil dry matter (DM) were 950 mg·kg-1 Fe, 3,110 mg·kg-1 Ca, 4,600 mg·kg-1 Mg, 443 mg·kg-1 Ni, 803 mg·kg-1 Mn, 26 mg·kg-1 Zn, 4 mg·kg-1 Cu, 43 mg·kg-1 Cr, 82 mg·kg-1 Co, 1 mg·kg-1 Cd, and 17 mg·kg-1 Pb. The Ca/Mg ratio in serpentine soils varied from 0.08 to 6.22. In A. murale plants, the maximum concentrations of Ni were up to 2,926 mg·kg-1 in roots, 6,793 mg·kg-1 in shoots, and 13,160 mg·kg-1 in leaves. Ca/Mg ratio in plant tissues were up to 2.25 (roots), 9.25 (shoots), and 15.23 (leaves). Cu content in the roots and shoots was high (up to 1,044 mg·kg-1 Cu and 849 mg·kg-1 Cu). This survey suggests that some A. murale populations from serpentine soils of Serbia emerge as strong Ni hyperaccumulators and can be used for phytoextraction purposes.