A BIOCHEMICAL APPROACH TO THE HEMIPARASITIC ACTION OF THE EPIPHYTIC LICHEN EVERNIA-PRUNASTRI ON BETULA-PENDULA

Evernia prunastri (L.) Ach., growing epiphytically on Betula pendula R oth, is able to penetrate into xylem vessels of its phytophore and to dissolve some lichen phenolics in the xylem sap. Evernic acid, the mai n phenolic of this lichen species, was characterized by HPLC (retentio n time 6.61 min) and IR spectrometry. It is acropetally translocated a nd, as a consequence, the apical zone of branches contains eight times as much evernic acid as the basal zone and the apical bud about 17 ti mes as much as the axillary buds. This lichen phenolic was been found in leaf tissues.