Differentiation of intersterility groups and geographic provenances among isolates of Heterobasidion annosum detected by random amplified polymorphic DNA assays.

Random amplified polymorphic DNAs were correlated with the intersterility group and the geographic provenance of 36 isolates of Heterobasidion annosum from North America and Europe and of one herbarium collection of basidiocarps from California. This technique is very precise and yields higher resolution than previous studies implementing techniques such as isozyme electrophoresis and restriction fragment length polymorphisms. Random amplified polymorphic DNAs revealed differentiation among the following geographic groups and intersterility groups: western North American P, eastern North American P, European P, North American S, Scandinavian S, Italian S, and Italian F. This is the first report on differentiation between eastern and western North American P isolates as well as between northern and southern European S isolates. Successful amplification of one dry basidiocarp suggests that random amplified polymorphic DNAs may be used to improve epidemiological and population studies of this pathogen.