RESPONSE OF Hypericum perforatum PLANTS TO SUPPLY OF CADMIUM COMPOUNDS CONTAINING DIFFERENT FORMS OF SELENIUM

The effect of cadmium compounds containing selenium in different oxidation states such as Se(IV), Se(VI), and Se(-II) on production characteristics, shoot water content and chlorophyll content in the leaves as well as Cd and Se accumulation in plant organs of Hypericum perforatum plants was investigated. Complexes with nicotinamide (nia) of the type Cd(NCX)(2)(nia)(2) where X = Se or S as well as CdSO4 were used to compare the effect of Se and S on the above-mentioned parameters. The studied compounds applied at concentrations 12, 24 and 60 mu mol . dm(-3) reduced dry mass of plant organs. In general, water content of shoots as well as chlorophyll content in the leaves decreased with increasing the compound concentrations. Se speciation significantly affected accumulated amount of Cd and Se [mg . g(-1) d.m.] in plant organs of H. perforatum plans what was reflected in the values of bioaccumulation factors (BAF), translocation factors (TF) as well as portion from the total metal amount accumulated by the plant occurring in the shoots. The comparison of the effect of CdSO4 and CdSeO4 as well as Cd(NCS)(2)(nia)(2) and Cd(NCSe)(2)(nia) showed that exchange of S for Se in the NCX- ligand led to decreased translocation of Cd into the shoots. The application of CdSeO4 resulted in intensive translocation of Cd as well as Se into the shoots. Portion of Cd allocated in shoots related to the total Cd amount accumulated by the plant was about 20% for treatment with CdSO4 and Cd(NCS)(2)(nia)(2), about 12.8, 10 and 6% for treatment with Cd(NCSe)(2)(nia)(2), CdSeO4 and CdSeO3. On the other hand, portion of Se allocated in shoots related to the total Se amount accumulated by H. perforatum plants achieved approx. 86, 48.6 and 45.9% after addition of CdSeO4, Cd(NCSe)(2)(nia)(2) and CdSeO3.