Effects of Thallus Damage on Interactions of Lichens with Non-Lichenized Fungi Under Natural and Laboratory Conditions

Abstract

Abstract The response of corticolous lichens to artificially induced chemical damage was compared to symptoms found on damaged lichens in the field. Experimental thalli were damaged and observed (1) in situ in a relatively pristine area, and (2) in a growth chamber either hydrated continuously or periodically. Lichenicolous fungi encountered included Cornutispora lichenicola, Lichenoconium erodens, Phoma cytospora, Vouauxiomyces truncatus, Hobsonia christiansenii, Pronectria oligospora, Nectria rubefaciens and its anamorph, Acremonium rhabdosporum , and a variety of hyphomycetes. The results support the idea that both thallus necrosis and moist conditions are necessary to produce the full suite of symptoms observed on ailing lichens in the field.