Establishment of in vitro plants selected from heavy metal contaminated soils for further phytoremediation use

Plant tissue culture techniques are a useful tool to obtain large amounts of biomass suitable for phytoremediation and repopulation of areas degraded by the presence of heavy metals. Phytoremediation implies the use of plants and associated soil microbes to reduce concentration or toxic effects of contaminants in the environment. Several abandoned mining areas are present around the Mediterranean basin, giving the opportunity to investigate the ability of selected plants to be used for phytoremediation and repopulation of dismissed mining areas. The aim of this study is the evaluation of two native Mediterranean plants (Dittrichia viscosa (L.) Greuter and Cistus monspeliensis L.), collected in a dismissed cave on Elba Island, for phytoremediation purpose. The selected species were micropropagated on different media to find optimal growth conditions. Different nutrient compositions were tested to mimic the original soil (extremely acidic pH and presence of heavy metals). Explants of both species grew under the stressed conditions, even if at different extent, demonstrating a tolerance similar to that of other plant species already utilized in phytoremediation. The results showed that the adaptation of plants derived from the polluted soils is kept in their micropropagated plant material, indicating that these shoots could be utilized for the repopulation in the considered polluted areas.