Fungal endophytes in a 400-million-yr-old land plant: infection pathways, spatial distribution, and host responses.
The Early Devonian Rhynie chert has been critical in documenting early land plant-fungal interactions. However, complex associations involving several fungi that enter into qualitatively different relationships with a single host plant and even interact with one another have not yet been detailed. Here, we studied petrographic thin sections of the Rhynie chert plant Nothia aphylla. Three fungal endophytes (co)occur in prostrate axes of this plant: narrow hyphae producing clusters of small spores; large spherical spores/zoosporangia; and wide aseptate hyphae that form intercellular vesicles in the cortex. Host responses on attack include bulging of infected rhizoids, formation of encasement layers around intracellular hyphae, and separation of infected from uninfected tissues by secondarily thickened cell walls. A complex simultaneous interaction of N. aphylla with three endophytic fungi was discovered. The host responses indicate that some of the mechanisms causing host responses in extant plants were in place 400 million yr ago. Anatomical and life history features of N. aphylla suggest that this plant may have been particularly susceptible to colonization by fungi.
Krings
Michael
M
Bayerische Staatssammlung für Paläontologie und Geologie und GeoBio-CenterLMU, Richard-Wagner-Straße 10, D-80333 Munich, Germany.|Department of Ecology and Evolutionary Biology, and Natural History Museum and Biodiversity Research Center, University of Kansas, Lawrence, KS 66045-7534, USA.
Taylor
Thomas N
TN
Department of Ecology and Evolutionary Biology, and Natural History Museum and Biodiversity Research Center, University of Kansas, Lawrence, KS 66045-7534, USA.
Hass
Hagen
H
Forschungsstelle für Paläobotanik am Geologisch-Paläontologischen Institut, Westfälische Wilhelms-Universität Münster, Hindenburgplatz 57, D-48143 Münster, Germany.
Kerp
Hans
H
Forschungsstelle für Paläobotanik am Geologisch-Paläontologischen Institut, Westfälische Wilhelms-Universität Münster, Hindenburgplatz 57, D-48143 Münster, Germany.
Dotzler
Nora
N
Bayerische Staatssammlung für Paläontologie und Geologie und GeoBio-CenterLMU, Richard-Wagner-Straße 10, D-80333 Munich, Germany.
Hermsen
Elizabeth J
EJ
Department of Ecology and Evolutionary Biology, and Natural History Museum and Biodiversity Research Center, University of Kansas, Lawrence, KS 66045-7534, USA.
D017753:Ecosystem; D005580:Fossils; D005658:Fungi / Q000145:classification / Q000502:physiology*; D010802:Phylogeny; D059828:Plant Cells; D018521:Plant Physiological Phenomena; D010944:Plants / Q000145:classification / Q000382:microbiology*