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Abstract Although it is known that arbuscular common mycorrhizal networks (CMNs) mediate below‐ground interactions between one or two species, little is understood about their role in mediating interactions among multiple, co‐occurring plant species.We investigated the CMN‐mediated interactions among two Central European species,Inula conyzaeandCrepis bienniswithin pots and the impact of a third plant, an invasiveEchinops sphaerocephalus, on these relationships. We examined changes in C‐to‐P exchange within a CMN formed byFunneliformis mosseaesourced from Central Europe by tracking plant C cost with13C signatures of 16:1ω5 and P acquisition to hosts with33P only accessible to CMNs.When only native plants were present, the C cost was consistent for both species, despite CMNs favouringC. bienniswith P uptake. In the presence ofE. sphaerocephalus, CMNs also favouredC. bienniswith P, but whileC. biennisandE. sphaerocephalusprovisioned similarly large portions of13C,I. conyzaeprovided less. Mycorrhizal P acquisition, therefore, was the costliest forE. sphaerocephalus, which likely mitigated someI. conyzae's C cost even though both received a low proportion of33P from CMNs.Echinops sphaerocephalusaltered mineral nutrient and C exchange proportions between native plants and their CMN, suggesting that this species alters below‐ground plant interactions and that not only specific characteristic of plant host and fungal partner but also the wider plant community mediates resource exchanges between CMNs and individual plants. Read the freePlain Language Summaryfor this article on the Journal blog.
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This content will become publicly available on October 1, 2025
Plant functional types and tissue stoichiometry explain nutrient transfer in common arbuscular mycorrhizal networks of temperate grasslands
Abstract Plants and mycorrhizal fungi form mutualistic relationships that affect how resources flow between organisms and within ecosystems. Common mycorrhizal networks (CMNs) could facilitate preferential transfer of carbon and limiting nutrients, but this remains difficult to predict. Do CMNs favour fungal resource acquisition at the expense of plant resource demands (a fungi‐centric view), or are they passive channels through which plants regulate resource fluxes (a plant‐centric view)?We used stable isotope tracers (13CO2and15NH3), plant traits, and mycorrhizal DNA to quantify above‐ and below‐ground carbon and nitrogen transfer between 18 plant species along a 520‐km latitudinal gradient in the Pacific Northwest, USA.Plant functional type and tissue stoichiometry were the most important predictors of interspecific resource transfer. Of ‘donor’ plants, 98% were13C‐enriched, but we detected transfer in only 2% of ‘receiver’ plants. However, all donors were15N‐enriched and we detected transfer in 81% of receivers. Nitrogen was preferentially transferred to annuals (0.26 ± 0.50 mg N per g leaf mass) compared with perennials (0.13 ± 0.30 mg N per g leaf mass). This corresponded with tissue stoichiometry differences.SynthesisOur findings suggest that plants and fungi that are located closer together in space and with stronger demand for resources over time are more likely to receive larger amounts of those limiting resources. Read the freePlain Language Summaryfor this article on the Journal blog.
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- Award ID(s):
- 2319597
- PAR ID:
- 10562084
- Publisher / Repository:
- Tamir Klein
- Date Published:
- Journal Name:
- Functional Ecology
- Volume:
- 38
- Issue:
- 10
- ISSN:
- 0269-8463
- Page Range / eLocation ID:
- 2184 to 2195
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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