Intraspecific Antagonism in Natural Populations of Wood-decaying Basidiomycetes

Abstract

Wood undergoing decay by a variety of white-rotting Basidiomycetes often contains narrow, dark, relatively undecayed zones separating decayed regions. Isolates derived from either side of such zones, although often of the same fungal species, are frequently antagonistic. Methods are described for investigating the genetic basis and significance of such intraspecific antagonism in natural populations of decay fungi within individual stumps and logs. Results obtained for Coriolus versicolorshow that decaying wood occupied by this fungus often contains populations of individual mutually antagonistic dikaryons, the monokaryotic components of which are often completely interfertile. These and similar results for other fungi suggest a fundamental departure from the concept of the unit mycelium.