title: Sebacinales are associates of the leafy liverwort Lophozia excisa in the southern maritime Antarctic.
abstract: The leafy liverwort Lophozia excisa, which is colonised by basidiomycete fungi in other biomes and which evidence suggests may be colonised by mycorrhizal fungi in Antarctica, was sampled from Léonie Island in the southern maritime Antarctic (67 degrees 36' S, 68 degrees 21' W). Microscopic examination of plants indicated that fungal hyphae colonised 78% of the rhizoids of the liverwort, apparently by entering the tips of rhizoids prior to growing into their bases, where they formed hyphal coils. Extensive colonisation of stem medullary cells by hyphae was also observed. DNA was extracted from surface-sterilised liverwort tissues and sequenced following nested PCR, using the primer set ITS1F/TW14, followed by a second round of amplification using the ITSSeb3/TW13 primer set. Neighbour-joining analyses showed that the sequences obtained nested in Sebacinales clade B as a 100% supported sister group to Sebacinales sequences from the leafy liverworts Lophozia sudetica, L. incisa and Calypogeia muelleriana sampled from Europe. Direct PCR using the fungal specific primer set ITS1F/ITS4 similarly identified fungi belonging to Sebacinales clade B as the principal colonists of L. excisa tissues. These observations indicate the presence of a second mycothallus in Antarctica and support the previous suggestion that the Sebacinales has a wide geographical distribution.
authors.affiliation: British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET, UK. kne@bas.ac.uk
authors.forename: Kevin K
authors.initials: KK
authors.lastname: Newsham
authors.forename: Paul D
authors.initials: PD
authors.lastname: Bridge
mesh_terms: D000864:Antarctic Regions; D001487:Basidiomycota / Q000254:growth & development* / Q000302:isolation & purification*; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D035926:Hepatophyta / Q000254:growth & development* / Q000382:microbiology*; D025301:Hyphae / Q000254:growth & development; D008853:Microscopy; D008969:Molecular Sequence Data; D010802:Phylogeny; D018547:Plant Stems / Q000382:microbiology; D017422:Sequence Analysis, DNA
chemical_list: D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer