Heavy metal stress in coincubation system -: Chlamydomonas reinhardtii/Pisum sativum

It was compared the potential of algae culture and extracted supernatant to modulate Pisum sativum stress response to heavy metals (copper and cadmium) treatment. The following experimental scheme was used: pea plants grown alone in water supplemented with 10, 20 and 30 mg/l CuSO4 or CdCl2 (experimental system I); pea plants grown in algal supernatant additionally supplemented with CuSO4 or CdCl2 (experimental system II), and pea plants grown in algal suspension supplemented with CuSO4 or CdCl2 (experimental system III). Pea plants growth was strongly inhibited after Cu-treatment in experimental system I, while it was almost unaffected in II and III experimental systems. It was found a strong decrease of chlorophyll a+b content in experimental system I after Cu treatment. A slight effect was observed in Cu-treated pea plants of experimental systems II and III. The highest concentrations of malone dialdehyde and hydrogen peroxide were measured in experimental system I after Cu- and Cd-treatment, whereas in experimental system II and III their contents were only slightly increased. Heavy metals were accumulated mainly in pea roots in all experimental systems. The highest accumulation of Cu and Cd was measured in the dry biomass of Chlamydonionas reinhardtii from experimental system III.