TOXIC ELEMENT FILTERING IN RHIZOPOGON ROSEOLUS PINUS-SYLVESTRIS MYCORRHIZAS COLLECTED FROM CALAMINE DUMPS

Rhizopogon roseoilus/Pinus sylvestris mycorrhizas collected from calam ine dumps (rich in Cd, Zn and Pb) were analysed by electron energy los s spectroscopy (EELS) connected to a transmission electron microscope. The distribution of potentially toxic elements within selected mycorr hizas was shown. Complementary data were obtained by cytochemical test s revealing the distribution of polysaccharides (PATAg) and cysteine-r ich proteins (Gomori-Swift reaction). The mycorrhizas investigated wer e characterized by the accumulation of Cd and Al in the fungal mantle and a gradual decrease of these elements was observed along the Hartig net towards the inside of the root, suggesting a filtering effect. Bo th of these elements were detected in the electron-opaque deposition i n the vacuoles, in periplasmic spaces as well as in the extracellular material. A comparatively high level of these elements was found in th e phenolic material of dead cortical cells. This was probably an addit ional source of toxic elements for the mycelium which was colonizing t he tannin cells.