Effect of Cd-Se interference on cadmium and selenium bioaccumulation in pea seedlings

Effect of three cadmium compounds (CdSeO4, CdSeO3 and Cd(NCSe)2(nia)2) containing Se in different oxidation states were used for experiments. Pea seedlings (cv. Felix) cultivated in hydroponic solutions under control conditions were treated with the above-mentioned compounds for two weeks (c = 3÷120 μmol dm). Then root and shoot dry mass was estimated and the concentrations of Cd and Se in plant organs were determined using AAS. Bioaccumulation factors related to both investigated elements (Cd, Se) as well as translocation factors were evaluated. Higher compound concentrations were toxic and desiccation of the shoots was observed. Cd concentration in the roots reached higher levels than in the shoots and accumulated Cd amount in plant organs increased with increasing Cd concentration. Whereas treatment with CdSeO3 and Cd(NCSe)2(nia)2 resulted in expressively higher Se concentration in roots, for CdSeO4 treatment Se concentration in shoots exceeded Se concentration in the roots. Therefore treatment with CdSeO4 resulted in much higher mobility of Cd and Se within the plants than the treatment with CdSeO3 and Cd(NCSe)2(nia)2.