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Phylogenetic relationships, host affinity, and geographic structure of boreal and arctic endophytes from three major plant lineages.
- Source :
-
Molecular phylogenetics and evolution [Mol Phylogenet Evol] 2007 Feb; Vol. 42 (2), pp. 543-55. Date of Electronic Publication: 2006 Jul 26. - Publication Year :
- 2007
-
Abstract
- Although associated with all plants, fungal endophytes (microfungi that live within healthy plant tissues) represent an unknown proportion of fungal diversity. While there is a growing appreciation of their ecological importance and human uses, little is known about their host specificity, geographic structure, or phylogenetic relationships. We surveyed endophytic Ascomycota from healthy photosynthetic tissues of three plant species (Huperzia selago, Picea mariana, and Dryas integrifolia, representing lycophytes, conifers, and angiosperms, respectively) in northern and southern boreal forest (Québec, Canada) and arctic tundra (Nunavut, Canada). Endophytes were recovered from all plant species surveyed, and were present in <1-41% of 2 mm2 tissue segments examined per host species. Sequence data from the nuclear ribosomal internal transcribed spacer region (ITS) were obtained for 280 of 558 isolates. Species-accumulation curves based on ITS genotypes remained non-asymptotic, and bootstrap analyses indicated that a large number of genotypes remain to be found. The majority of genotypes were recovered from only a single host species, and only 6% of genotypes were shared between boreal and arctic communities. Two independent Bayesian analyses and a neighbor-joining bootstrapping analysis of combined data from the nuclear large and small ribosomal subunits (LSUrDNA, SSUrDNA; 2.4 kb) showed that boreal and arctic endophytes represent Dothideomycetes, Sordariomycetes, Chaetothyriomycetidae, Leotiomycetes, and Pezizomycetes. Many well-supported phylotypes contained only endophytes despite exhaustive sampling of available sequences of Ascomycota. Together, these data demonstrate greater than expected diversity of endophytes at high-latitude sites and provide a framework for assessing the evolution of these poorly known but ubiquitous symbionts of living plants.
- Subjects :
- Ascomycota classification
Ascomycota growth & development
Canada
DNA, Fungal chemistry
DNA, Fungal genetics
DNA, Intergenic chemistry
DNA, Intergenic genetics
DNA, Ribosomal chemistry
DNA, Ribosomal genetics
Ecosystem
Huperzia microbiology
Molecular Sequence Data
Picea microbiology
Rosacea microbiology
Sequence Analysis, DNA
Ascomycota genetics
Phylogeny
Plants microbiology
Subjects
Details
- Language :
- English
- ISSN :
- 1055-7903
- Volume :
- 42
- Issue :
- 2
- Database :
- MEDLINE
- Journal :
- Molecular phylogenetics and evolution
- Publication Type :
- Academic Journal
- Accession number :
- 17005421
- Full Text :
- https://doi.org/10.1016/j.ympev.2006.07.012