Genetic structure of Fennoscandian populations of the threatened wood-decay fungus Fomitopsis rosea (Basidiomycota).
The genetic structure of five Fennoscandian populations of the threatened wood-decay fungus Fomitopsis rosea (Basidiomycota) was investigated using codominant PCR-RFLP, allele specific amplification (ASA) markers, inter simple sequence repeat (ISSR) markers and mating studies. Sequence analyses of a subset of single spore isolates revealed sequence variation in four target sequences; internal transcribed spacer (ITS) and intergenic spacer (IGS1) of the nuclear ribosomal DNA, the translation elongation factor 1 alpha (efa) gene and the super oxide dismutase (sod) gene. No sequence variation was found in amplified portions of the mitochondrial large and small rRNA genes. Genotype distributions were mostly (90%) in accordance with Hardy-Weinberg expectations, and the nrDNA markers (ITS/IGS1), efa and sod were in most cases (87%) in linkage equilibrium, indicating an outcrossing reproductive mode, panmictic conditions and large population sizes of the fungus. Mating tests confirmed that F. rosea exhibits an outcrossing bipolar heterothallic mating system. Mating allele richness was high in two investigated populations. Phylogenetic analyses of ITS and IGS1 sequences from the five geographic populations revealed some geographic sub-structuring of the ITS sequences, but no sub-structuring of IGS1. The nrDNA (ITS/IGS1), efa and sod markers gave a low overall FST (0.013). The ISSR markers gave no clustering of the populations in UPGMA, and the between-population variance component was very low in AMOVA (0.4%), indicating a high level of gene flow.
Department of Biology, Division of Botany and Plant Physiology, University of Oslo, P.O. Box 1045, Blindern, N-0316 Oslo, Norway. haavarka@bio.uio.no
Håvard
H
Kauserud
Trond
T
Schumacher
D000483:Alleles; D001483:Base Sequence; D001487:Basidiomycota / Q000145:classification* / Q000235:genetics* / Q000502:physiology; D001673:Biodegradation, Environmental; D003247:Conservation of Natural Resources; D004271:DNA, Fungal / Q000032:analysis; D004275:DNA, Ribosomal / Q000032:analysis; D017753:Ecosystem; D005787:Gene Frequency; D005819:Genetic Markers; D014644:Genetic Variation; D018895:Microsatellite Repeats; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D017422:Sequence Analysis, DNA; D014197:Trees; D014934:Wood
D004271:DNA, Fungal; D004275:DNA, Ribosomal; D005819:Genetic Markers