Differential metal-specific tolerance and accumulation patterns among Thlaspi caerulescens populations originating from different soil types

Here, Thlaspi caerulescens populations from contrasting soil types (serpentine, calamine and nonmetalliferous) were characterized with regard to tolerance, uptake and translocation of zinc (Zn), cadmium (Cd) and nickel (Ni) in hydroponic culture. Results showed that high-level tolerances were apparently metal-specific and confined to the metals that were enriched at toxic levels in the soil at the population site. With regard to metal accumulation, results suggested that, unlike Zn hyperaccumulation, Cd and Ni hyperaccumulation were not constitutive at the species level in T. caerulescens . In general, the populations under study exhibited a pronounced uncorrelated and metal-specific variation in uptake, root to shoot translocation, and tolerance of Zn, Cd and Ni. The distinct intraspecific variation of these characters provides excellent opportunities for further genetic and physiological dissection of the hyperaccumulation trait.