METAL-ION ADSORPTION BY PSEUDOSCLEROTIAL PLATES OF PHELLINUS-WEIRII

Melanized pseudosclerotial plates, commonly referred to as zone lines, form at colony boundaries of Phellinus weirii and other white-rot fun gi in response to various stimuli. Pseudosclerotial plates of P. weiri i produced in the laboratory can sequester metal ions from contact wit h soil in concentrations up to fifteen times greater than found in the soil. Phellinus weirii accumulated greater ion concentrations for 11 of 13 elements assayed than did Fomitopsis pinicola, a brown rot fungu s that produces thick mycelial mats but does not produce melanized pse udosclerotial plates. Ion concentrations for 10 of 13 elements were si gnificantly greater in soil-treated pseudosclerotial plates of P. weir ii than in controls. Aluminum and iron concentrations for soil-treated pseudosclerotial plates of P. weirii were 152 and 117 times greater, respectively, than that of controls. Ion concentration for untreated m ats of P. weirii and F. pinicola were not significantly different in 1 2 of 13 elements assayed. The metal ion-rich outer layer of the pseudo sclerotial plates of P. weirii may help in protecting the fungus from combative antagonistic organisms and enhance long-term saprophytic sur vival of this fungus.