Rapid Detection of European Heterobasidion annosum Intersterility Groups and Intergroup Gene Flow Using Taxon‐specific Competitive‐Priming PCR (TSCP‐PCR)

Using taxon-specific competitive-priming polymerase chain reaction (TSCP-PCR) the intersterility groups (ISGs) S and P of the root and butt rot pathogen Heterobasidion annosum were found in an active pine mortality center in the forest region Tharandter Wald (Saxonia, Germany). All isolates from spruce were typed as S, and all isolates from pine were P, except for two isolates which were identified as hybrid 'SP' genets. These results indicate the possibility of gene flow in nature between the two ISGs in Europe.