VARIATION IN THE CLADONIA-CHLOROPHAEA COMPLEX-II - RIBOSOMAL DNA VARIATION IN A SOUTHERN APPALACHIAN POPULATION

A Southern Appalachian population of the Cladonia chlorophaea complex from Mt. Rogers, Virginia, containing individuals of four sympatric chemotypes, shows extensive variation in ribosomal DNA (rDNA). Variation was detected by 1) Southern hybridization of total genomic DNA with an rDNA probe; and 2) restriction-site digests of a variable region of the rDNA gene amplified by the polymerase chain reaction (PCR). At least 24 restriction-fragment patterns were identified that produced PCR products of four lengths and nine restriction-fragment patterns. Three of the chemotypes, each represented by more than one individual, had multiple rDNA restriction-fragment patterns, and two patterns were shared among chemotypes. The large number of restriction-fragment patterns suggests that some are polymorphic within interbreeding groups, and the sharing of patterns among chemotypes suggests that some chemotypes may be polymorphisms of a single species.