Characterization of simple sequence repeat loci for Peltigera membranacea (lichenized Ascomycota) and its Nostoc photobiont

Abstract

To facilitate population-genetic studies, we developed simple sequence repeat (SSR) markers and a molecular species identification assay for Peltigera membranacea (Ascomycota, Peltigerales), a common ground-dwelling lichen of forest and tundra ecosystems. Additional markers were developed for its Nostoc photobiont. Twenty-one fungal markers for P. membranacea were found to be polymorphic, with the number of alleles ranging from 3-21. Nei's unbiased gene diversity ranged from 0.588 to 0.640 in four significantly structured (FST = 0.059) mycobiont populations. For the Nostoc photobiont, 14 polymorphic SSR were developed, yielding 4-14 alleles each, with gene diversity ranging from 0.062 to 0.771 in four populations showing substantial population structure (FST = 0.278). The new markers developed are suitable for population genetic studies of Peltigera membranacea and of its cyanobiont, and at the same time allowed us to distinguish 98.5% of P. membranacea specimens from morphologically similar species of Peltigera.