Maher Necib’s research while affiliated with Center of Biotechnogy of Borj Cédria and other places

Atriplex halimus L. is a promising xero-halophyte species for phytoremediation purposes but displays high levels of genetic variability. As an attempt to select uniform material suitable for phytomanagement, five clones were established by cuttings from three non-polluted sites (Tunis, Nabeul and Sfax), one moderately Pb-polluted site (Sousse) and a highly polymetallic polluted mining site (Gafsa). Cuttings were cultivated during 90 days under controlled conditions on soil issued from the most polluted area. The clone from Gafsa accumulated higher concentrations of metals in roots (Cr) and leaves (Cd, Sr, Zn and Cu) than other clones. Gafsa showed the highest absorption efficiency, translocation factor, bioconcentration factor and bioaccumulation coefficient compared to other clones but displayed the lowest relative growth rate (RGR) value while the highest RGR was found in the clone from Sousse. Heavy metal tolerance in Gafsa was not related to a more efficient management of oxidative stress or higher concentration of phytochelatins. Total amount of Sr and Zn removed from the substrate was the highest for Sousse while removal of Cd, Cu, Cr and Ni was the highest for Gafsa. It is concluded that cuttings allow to obtain uniform material for phytoremediation by Atriplex halimus and that combining different clones with complementary properties is an attractive option for phytomanagement of polymetallic polluted soils by this species.