|1||Department of Evolutionary Botany, Botanical Institute, University of Copenhagen, Gothersgade 140, DK-1123 Copenhagen K, Denmark|
|2||3060 Valley Life Sciences Building, Integrative Biology, University of California, Berkeley, California 94720, USA|
|3||Department of Mycology, Botanical Institute, University of Copenhagen, Øster Farimagsgade 2D, DK-1353 Copenhagen K, Denmark|
|4||Danish Forest and Landscape Research Institute, Hørsholm Kongevej 11, DK-2970 Hørsholm, Denmark|
The mitochondrial ribosomal large subunit (Ls) DNA was used to identify the orchid mycorrhizal fungi found in roots of Dactylorhiza majalis. The gene was amplified using DNA extracted from single pelotons obtained from fresh and silica gel dried roots. Furthermore, sequencing a variety of well-characterized orchid isolates expanded the fungal database of the mitochondrial ribosomal LsDNA. Polymerase chain reaction product length variants present in D. majalis were sequenced and identified using the expanded database. These analyses revealed two different peloton-forming fungi in samples from D. majalis, which sometimes occurred together as a single two-taxa peloton within the same cortex cell. The first taxon belonged to the genus Tulasnella and the second taxon was distantly related to Laccaria.