Effects of copper pollution on the ultrastructure of Lessonia spp.

Plants of Lessonia trabeculata and L. nigrescens were studied by transmissi on electron microscopy in order to evaluate ultrastructural level changes i n response to copper exposure. Samples of fronds, stipes, and holdfasts wer e collected from areas with and without copper mining discharges. Changes i n cell ultrastructure observed in Lessonia trabeculata were related to copp er concentrations in seawater, seaweeds and extracted alginates. The result s strongly suggest that tolerance or adaptation of Lessonia to high concent rations of copper is the capacity of different plant tissues to accumulate copper as precipitates, primarily at two levels: the cell wall and periplas malemmal space, with the vacuolar system being a third site.