Nickel and other metal uptake and accumulation by species of Alyssum (Brassicaceae) from the ultramafics of Iran

Some plants growing on serpentine (ultramafic) soils are able to hyperaccumulate nickel in their above-ground parts. The genus Alyssum L. contains the greatest number of Ni-hyperaccumulator plants so far reported. There are substantial areas of serpentine soils at many locations in Iran. This paper presents the analyses for Ni, Cr, Mn, Fe, Mg and Ca in soils and Alyssum species from the ultramafics of west and northwest Iran. Soil analysis for total elements in these areas indicates that typical concentrations of Ni, Cr, Mn, Fe, Mg and Ca are up to about 1240, 365, 800, 51,150, 152,390 and 11,790 μg g−1, respectively. During this study, seven Alyssum species were collected. Analysis of leaf dry matter shows that Alyssum bracteatum can contain up to 2300 μg Ni g−1, while the other species contain much lower concentrations of Ni and other elements. A. bracteatum is endemic to Iran and the first Ni hyperaccumulator reported from this species.