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Abstract Following disturbances such as wildfires, oak seedlings must form a symbiotic association with mycorrhizal fungi to survive. Wildfires, however, reduce available mycorrhizal fungal propagules in the soil. Ectomycorrhizal (ECM) fungi on oak seedlings sampled in severely burned (7 sites), moderately burned (7 sites), and unburned areas (8 sites) in the Great Smoky Mountains National Park were evaluated 21 months after the 2016 Chimney Tops 2 Wildfire by Sanger sequencing of the nuclear ribosomal DNA internal transcribed spacer region (nrITS; fungal barcode). Sequences were aligned and grouped into Operational Taxonomic Units (OTUs) based on well-supported phylogenetic clades and 98–100% nrITS sequence homology with sequences in GenBank. One hundred seventy-nine root-associated fungi comprising 124 OTUs were recovered after removing duplicates (the same fungus on two or more roots of the same plant). The ECM genusRussulawas the most diverse genus (25 OTUs), followed by theThelephora/Tomentellaclade (18 OTUs),Lactifluus(8 OTUs),Lactarius(4 OTUs), and Laccariaaff.laccata(2 OTUs).RussulaOTUs were identified more frequently on oak roots from burned areas and in burned soils, suggesting that someRussulataxa may have a selective advantage in burned areas. High alpha diversity occurred within each of the burn categories, but little overlap of taxa occurred between burn categories (high beta diversity). Approximately half of the recovered OTUs (100/179 total root-associated fungi = 55.9%) were found on a single plant. Oak seedlings growing in moderately and severely burned areas 21 months after a fire were capable of forming root associations with available fungi. In contrast to the expectation that root-associated fungal diversity would be reduced after a wildfire, diversity 1 year after the Chimney Tops 2 Fire was high with ectomycorrhizalLaccaria,Russulaceae, andThelephoraceaedominating. This study suggests that the availability of ECM fungi post-fire is not a barrier to oak re-establishment.
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Suillus : an emerging model for the study of ectomycorrhizal ecology and evolution
Summary Research on mycorrhizal symbiosis has been slowed by a lack of established study systems. To address this challenge, we have been developingSuillus, a widespread ecologically and economically relevant fungal genus primarily associated with the plant family Pinaceae, into a model system for studying ectomycorrhizal (ECM) associations. Over the last decade, we have compiled extensive genomic resources, culture libraries, a phenotype database, and protocols for manipulatingSuillusfungi with and without their tree partners. Our efforts have already resulted in a large number of publicly available genomes, transcriptomes, and respective annotations, as well as advances in our understanding of mycorrhizal partner specificity and host communication, fungal and plant nutrition, environmental adaptation, soil nutrient cycling, interspecific competition, and biological invasions. Here, we highlight the most significant recent findings enabled bySuillus, present a suite of protocols for working with the genus, and discuss howSuillusis emerging as an important model to elucidate the ecology and evolution of ECM interactions.
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- Award ID(s):
- 2029168
- PAR ID:
- 10499199
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 242
- Issue:
- 4
- ISSN:
- 0028-646X
- Format(s):
- Medium: X Size: p. 1448-1475
- Size(s):
- p. 1448-1475
- Sponsoring Org:
- National Science Foundation
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