Grouping of lignin degrading corticioid fungi based on RFLP analysis of 18S rDNA and ITS regions

Twelve wood decaying species of Phlebia and Phanerochaete were analysed by RFLP (restriction fragment length polymorphism) analysis of an 18S rRNA gen e fragment and an ITS region. The data obtained by different restriction en donucleases were used to construct phenograms based on the UPGMA algorithm. PCR-RFLP within the 18S rRNA gene was sufficient to distinguish between Ph lebia species but did not show variation among Phanerochaete spp. ITS regio n amplified from Phlebia spp. varied in length from 570-745 bp. The smalles t ITS fragment was amplified from P. subcretacea and the longest from P, hy dnoides. The size of ITS fragments amplified from Phanerochaete spp. was un iform (635 bp), except for the ITS from two P, sanguinea strains (690 bp). RFLP analysis within ITS amplified from Phanerochaete spp. distinguished be tween them. Results from PCR-RFLP of 18S rRNA and ITS strongly suggest that Phiebia gigantea is closely related to Phanerochaete. Morphological charac teristics (lack of clamp connections in hymenium, well developed subiculum) further support this hypothesis.