Imbalanced carbon-for-phosphorus exchange between European arbuscular mycorrhizal fungi and non-native Panicum grasses-A case of dysfunctional symbiosis

0482851 - MBÚ 2018 RIV DE eng J - Journal Article
Řezáčová, Veronika - Slavíková, Renata - Konvalinková, Tereza - Hujslová, Martina - Gryndlerová, Hana - Gryndler, Milan - Püschel, David - Jansa, Jan
Imbalanced carbon-for-phosphorus exchange between European arbuscular mycorrhizal fungi and non-native Panicum grasses-A case of dysfunctional symbiosis.
Pedobiologia. Roč. 62, May 2017 (2017), s. 48-55. ISSN 0031-4056. E-ISSN 1873-1511
R&D Projects: GA MŠMT(CZ) LK11224; GA ČR(CZ) GA14-19191S; GA AV ČR(CZ) Fellowship J. E. Purkyně
Grant - others:AV ČR(CZ) Fellowship J. E. Purkyně
Program: Fellowship J. E. Purkyně
Institutional support: RVO:61388971
Keywords : Arbuscular mycorrhiza * Panicum * Plant biomass
OECD category: Microbiology
Impact factor: 2.288, year: 2017

Arbuscular mycorrhizal fungi (AMF) are globally widespread root symbionts of the majority of terrestrial plant species, they are present in almost all soils, and show particularly low levels of partner specificity. Usually, they benefit their plant hosts through increased nutrients (especially phosphorus, P) supply, improved growth, stress tolerance and fitness as compared to the non-mycorrhizal plants. In exchange for the symbiotic benefits, plant supplies the fungal partner with carbon (C), constituting symbiotic costs for the plant. Here we tested the effect of four soil treatments, combining removal of indigenous AMF communities and/or supplementation with mineral P to restore plant P nutrition, on plant growth and C fluxes from plant to soil as well as on mineral nutrition of a C-3 and a congeneric C-4 grass species. Contrary to all expectations, both plant species showed lower P and nitrogen contents, and grew smaller, though allocated more C belowground, when supplied with AMF-containing full soil inoculum as compared to AMF-free inoculum. Our results indicate possible incompatibility of symbiotic partners of different geographic origin (European AMF and tropical/subtropical grasses from Africa/Asia), leading to apparent parasitism of the plants by the AMF communities in terms of both growth and nutritional responses. Most likely, downregulation of the direct (root) P uptake pathway by the plants in response to mycorrhiza formation over-compensated the symbiotic (indirect) P acquisition via mycorrhizal hyphae. The observed effects could also have been caused (or contributed to) by the relatively young age of the experimental plants, and different composition of microbial communities in the two inoculant (containing or not the AMF).
Permanent Link: http://hdl.handle.net/11104/0278243