POLYMORPHISMS IN THE LARGE INTERGENIC SPACER OF THE NUCLEAR RIBOSOMALREPEAT IDENTIFY LACCARIA-PROXIMA STRAINS

A simple method for identifying strains of Laccaria proxima is present ed which uses the polymerase chain reaction (PCR) to amplify the large intergenic spacer region of the nuclear ribosomal repeat The large in tergenic spacer region of L. proxima is approximately 4000 base pairs long and is variable enough to permit clear identification of individu al strains after digestion with restriction endonucleases. This has on ly been partially possible with other published PCR-based identificati on methods which use conserved primers. The method has the potential t o be adapted for use in identifying isolates directly from roots and a voids the use of labeled probes needed for identifying Laccaria strain s with techniques which are not PCR-based.