ULTRASTRUCTURAL RESPONSE OF CABBAGE OUTER LEAF MESOPHYLL CELLS (BRASSICA OLERACEA L.) TO EXCESS OF NICKEL

摘要

Changes in the structure and in the ultrastructure of cabbage outer leaf mesophyll cells [Brassica oleracea L.] cv. Slawa from Enkhouizen were examined by means of light and electron microscopy. The examined plants were grown on the basic Murashige and Skoog medium with addition of excessive concentrations of nickel (added as NiSO_4 x 7H_2O), i.e. Ni 5 Ni 10 And Ni 20 mg/dm~3 In Ni 5 mg samples mainly adaptation changes to the conditions of stress were observed. These changes Were manifested by the increase of cytoplasm content and by cytoplasm vacuolization, by the increase of nucleus and unc- Leous volume, nucleolus vacuolization, the increase of plasmalemma invaginations and of the amount of rough ER, by the Central arrangement of smooth ER and of the thylakoids of chloroplasts; it was also shown by the growth of the number of Mitochondria and of peroxisomes in the cell.