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Title: Nutrient exchange within common mycorrhizal networks is altered in a multispecies environment
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.  more » « less
Award ID(s):
2145142
PAR ID:
10579266
Author(s) / Creator(s):
; ;
Publisher / Repository:
British Ecological Society
Date Published:
Journal Name:
Functional Ecology
Volume:
39
Issue:
2
ISSN:
0269-8463
Page Range / eLocation ID:
418 to 431
Subject(s) / Keyword(s):
13C labelling 16:1ω5 arbuscular mycorrhiza below-ground interactions interspecific plant competition invasive plant species mycorrhizal carbon cost symbiotic 33P benefits
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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