Suppression of arbuscular mycorrhizal fungal activity in a diverse collection of non-cultivated soils

TY - JOUR

T1 - Suppression of arbuscular mycorrhizal fungal activity in a diverse collection of non-cultivated soils

AU - Cruz Paredes, Carla

AU - Svenningsen, Nanna Bygvraa

AU - Nybroe, Ole

AU - Kjøller, Rasmus

AU - Frøslev, Tobias Guldberg

AU - Jakobsen, Iver

PY - 2019/3

Y1 - 2019/3

N2 - Most plants form symbiotic associations with arbuscular mycorrhizal fungi (AMF). AMF increase the uptake of plant nutrients by extending their extra-radical mycelium (ERM) in the soil where other groups of microorganisms may suppress the activity of the ERM. However, little is known about such suppression in natural soils. This work aimed to investigate the incidence of AMF suppression among soils sampled from highly variable natural ecosystems, and used 33 P uptake by the ERM to evaluate AMF activity. A second aim was to identify factors behind the observed AMF-suppression. We found that AMF-suppressiveness varied markedly among natural soils and occurred more frequently in low pH than in high pH soils. A previous study for cultivated soils revealed a strong biological component of suppressiveness against AMF, and in accordance we found that the composition of both fungal and bacterial communities differed significantly between AMF-suppressive and non-suppressive natural soils. Acidobacteria, Acidothermus, Xanthomonadaceae, Archaeorhizomyces sp., Mortierella humilis and some Mycena spp. were significantly more abundant in AMF-suppressive soils and may therefore be direct antagonists of AMF. This implies that the functioning of AMF in natural ecosystems is strongly modulated by specific soil microbes.

AB - Most plants form symbiotic associations with arbuscular mycorrhizal fungi (AMF). AMF increase the uptake of plant nutrients by extending their extra-radical mycelium (ERM) in the soil where other groups of microorganisms may suppress the activity of the ERM. However, little is known about such suppression in natural soils. This work aimed to investigate the incidence of AMF suppression among soils sampled from highly variable natural ecosystems, and used 33 P uptake by the ERM to evaluate AMF activity. A second aim was to identify factors behind the observed AMF-suppression. We found that AMF-suppressiveness varied markedly among natural soils and occurred more frequently in low pH than in high pH soils. A previous study for cultivated soils revealed a strong biological component of suppressiveness against AMF, and in accordance we found that the composition of both fungal and bacterial communities differed significantly between AMF-suppressive and non-suppressive natural soils. Acidobacteria, Acidothermus, Xanthomonadaceae, Archaeorhizomyces sp., Mortierella humilis and some Mycena spp. were significantly more abundant in AMF-suppressive soils and may therefore be direct antagonists of AMF. This implies that the functioning of AMF in natural ecosystems is strongly modulated by specific soil microbes.

KW - Arbuscular mycorrhizal fungi

KW - Interactions

KW - Microbiome

KW - Natural ecosystems

KW - Suppressive soil

U2 - 10.1093/femsec/fiz020

DO - 10.1093/femsec/fiz020

M3 - Journal article

C2 - 30715290

AN - SCOPUS:85063905185

SN - 0168-6496

VL - 95

SP - 1

EP - 10

JO - FEMS Microbiology Ecology

JF - FEMS Microbiology Ecology

IS - 3

M1 - fiz020

ER -