Shifts in Ectomycorrhizal Fungal Communities and Exploration Types Relate to the Environment and Fine-Root Traits Across Interior Douglas-Fir Forests of Western Canada

• Published in: Frontiers in plant science Vol. 10; p. 643
• Main Authors: Defrenne, Camille E, Philpott, Timothy J, Guichon, Shannon H A, Roach, W Jean, Pickles, Brian J, Simard, Suzanne W
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 22.05.2019
• Subjects: biogeographic gradient; ectomycorrhizal fungi; exploration type; fine-root traits; forest ecosystems; functional ecology; Plant Science; exploration type; biogeographic gradient; fine-root traits; functional ecology; Pseudostuga menziesii var. glauca; mycorrhizas; ectomycorrhizal fungi; forest ecosystems
• ISSN: 1664-462X; 1664-462X
• DOI: 10.3389/fpls.2019.00643

Large-scale studies that examine the responses of ectomycorrhizal fungi across biogeographic gradients are necessary to assess their role in mediating current and predicted future alterations in forest ecosystem processes. We assessed the extent of environmental filtering on interior Douglas-fir ( var. (Beissn.) Franco) ectomycorrhizal fungal communities across regional gradients in precipitation, temperature, and soil fertility in interior Douglas-fir dominated forests of western Canada. We also examined relationships between fine-root traits and mycorrhizal fungal exploration types by combining root and fungal trait measurements with next-generation sequencing. Temperature, precipitation, and soil C:N ratio affected fungal community dissimilarity and exploration type abundance but had no effect on α-diversity. Fungi with rhizomorphs (e.g., sp.) or proteolytic abilities (e.g., sp.) dominated communities in warmer and less fertile environments. Ascomycetes (e.g., ) or shorter distance explorers, which potentially cost the plant less C, were favored in colder/drier climates where soils were richer in total nitrogen. Environmental filtering of ectomycorrhizal fungal communities is potentially related to co-evolutionary history between Douglas-fir populations and fungal symbionts, suggesting success of interior Douglas-fir as climate changes may be dependent on maintaining strong associations with local communities of mycorrhizal fungi. No evidence for a link between root and fungal resource foraging strategies was found at the regional scale. This lack of evidence further supports the need for a mycorrhizal symbiosis framework that is independent of root trait frameworks, to aid in understanding belowground plant uptake strategies across environments.