DIFFERENTIATION AND GROUPING OF ISOLATES OF THE GANODERMA-LUCIDUM COMPLEX BY RANDOM AMPLIFIED POLYMORPHIC DNA-PCR COMPARED WITH GROUPING ONTHE BASIS OF INTERNAL TRANSCRIBED SPACER SEQUENCES

Laccate polypores of the Ganoderma lucidum species complex are widespr ead white rot fungi of economic importance, but isolates cannot be ide ntified by traditional taxonomic methods. Parsimony analysis of nucleo tide sequences from the internal transcribed spacers (ITS) of the ribo somal gene (rDNA) distinguished six lineages in this species complex. Each ITS lineage may represent one or more putative species. While som e isolates have identical ITS sequences, all of them could be clearly differentiated by genetic fingerprinting using random amplified polymo rphic DNA (RAPD). To investigate the suitability of RAPD markers for t axonomic identification and grouping of isolates of the G. lucidum com plex, RAPD fragments (RAPDs) were used as phenotypic characters in num erical and parsimony analyses, Results show that data from RAPDs do no t distinguish the same clades as ITS data do. Groupings based on analy sis of RAPD data were very sensitive to the choice of the grouping met hod used, and no consistent grouping of isolates could be proposed. Ho wever, analysis dth RAPDs did resolve several robust terminal clades c ontaining putatively conspecific isolates, suggesting that RAPDs might . be helpful for systematics at the lower taxonomic levels that are un resolved by ITS sequence data. The limitations of RAPDs for systematic s are briefly discussed. The conclusion of this study is that ITS sequ ences can be used to identify isolates of the G. lucidum complex, wher eas RAPDs can be used to differentiate between isolates having identic al ITS sequences. The practical implications of these results are brie fly illustrated.