Trophic interactions as determinants of the arbuscular mycorrhizal fungal community with cascading plant-promoting consequences

Abstract Background The soil mycobiome is composed of a complex and diverse fungal community, which includes functionally diverse species ranging from plant pathogens to mutualists. Among the latter are arbuscular mycorrhizal fungi (AMF) that provide phosphorous (P) to plants. While plant hosts and abiotic parameters are known to structure AMF communities, it remains largely unknown how higher trophic level organisms, including protists and nematodes, affect AMF abundance and community composition. Results Here, we explored the connections between AMF, fungivorous protists and nematodes that could partly reflect trophic interactions, and linked those to rhizosphere P dynamics and plant performance in a long-term manure application setting. Our results revealed that manure addition increased AMF biomass and the density of fungivorous nematodes, and tailored the community structures of AMF, fungivorous protists, and nematodes. We detected a higher abundance of AMF digested by the dominant fungivorous nematodes Aphelenchoides and Aphelenchus in high manure treatments compared to no manure and low manure treatments. Structural equation modeling combined with network analysis suggested that predation by fungivorous protists and nematodes stimulated AMF biomass and modified the AMF community composition. The mycorrhizal-fungivore interactions catalyzed AMF colonization and expression levels of the P transporter gene ZMPht1;6 in maize roots, which resulted in enhanced plant productivity. Conclusions Our study highlights the importance of predation as a key element in shaping the composition and enhancing the biomass of AMF, leading to increased plant performance. As such, we clarify novel biological mechanism of the complex interactions between AMF, fungivorous protists, and nematodes in driving P absorption and plant performance.

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Temporal dynamics of mycorrhizal fungal communities and co-associations with grassland plant communities following experimental manipulation of rainfall

10.32942/osf.io/t82ug ◽

2019 ◽

Cited By ~ 1

Author(s):

Coline Deveautour ◽

Sally Power ◽

Kirk Barnett ◽

Raul Ochoa-Hueso ◽

Suzanne Donn ◽

...

Keyword(s):

Community Composition ◽

Plant Community ◽

Plant Communities ◽

Fungal Community ◽

Mycorrhizal Fungi ◽

Temporal Dynamics ◽

Arbuscular Mycorrhizal ◽

Fungal Communities ◽

Plant Responses ◽

Rainfall Regimes

Climate models project overall a reduction in rainfall amounts and shifts in the timing of rainfall events in mid-latitudes and sub-tropical dry regions, which threatens the productivity and diversity of grasslands. Arbuscular mycorrhizal fungi may help plants to cope with expected changes but may also be impacted by changing rainfall, either via the direct effects of low soil moisture on survival and function or indirectly via changes in the plant community. In an Australian mesic grassland (former pasture) system, we characterised plant and arbuscular mycorrhizal (AM) fungal communities every six months for nearly four years to two altered rainfall regimes: i) ambient, ii) rainfall reduced by 50% relative to ambient over the entire year and iii) total summer rainfall exclusion. Using Illumina sequencing, we assessed the response of AM fungal communities sampled from contrasting rainfall treatments and evaluated whether variation in AM fungal communities was associated with variation in plant community richness and composition. We found that rainfall reduction influenced the fungal communities, with the nature of the response depending on the type of manipulation, but that consistent results were only observed after more than two years of rainfall manipulation. We observed significant co-associations between plant and AM fungal communities on multiple dates. Predictive co-correspondence analyses indicated more support for the hypothesis that fungal community composition influenced plant community composition than vice versa. However, we found no evidence that altered rainfall regimes were leading to distinct co-associations between plants and AM fungi. Overall, our results provide evidence that grassland plant communities are intricately tied to variation in AM fungal communities. However, in this system, plant responses to climate change may not be directly related to impacts of altered rainfall regimes on AM fungal communities. Our study shows that AM fungal communities respond to changes in rainfall but that this effect was not immediate. The AM fungal community may influence the composition of the plant community. However, our results suggest that plant responses to altered rainfall regimes at our site may not be resulting via changes in the AM fungal communities.

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Clary Sage Cultivation and Mycorrhizal Inoculation Influence the Rhizosphere Fungal Community of an Aged Trace-Element Polluted Soil

Microorganisms ◽

10.3390/microorganisms9061333 ◽

2021 ◽

Vol 9 (6) ◽

pp. 1333

Author(s):

Robin Raveau ◽

Anissa Lounès-Hadj Sahraoui ◽

Mohamed Hijri ◽

Joël Fontaine

Keyword(s):

Trace Element ◽

Community Composition ◽

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Illumina Miseq ◽

Amplicon Sequencing ◽

Fungal Communities ◽

Rhizospheric Soil ◽

Lead Smelter ◽

Amf Communities

Soil fungal communities play a central role in natural systems and agroecosystems. As such, they have attracted significant research interest. However, the fungal microbiota of aromatic plants, such as clary sage (Salvia sclarea L.), remain unexplored. This is especially the case in trace element (TE)-polluted conditions and within the framework of phytomanagement approaches. The presence of high concentrations of TEs in soils can negatively affect not only microbial diversity and community composition but also plant establishment and growth. Hence, the objective of this study is to investigate the soil fungal and arbuscular mycorrhizal fungi (AMF) community composition and their changes over time in TE-polluted soils in the vicinity of a former lead smelter and under the cultivation of clary sage. We used Illumina MiSeq amplicon sequencing to evaluate the effects of in situ clary sage cultivation over two successive years, combined or not with exogenous AMF inoculation, on the rhizospheric soil and root fungal communities. We obtained 1239 and 569 fungal amplicon sequence variants (ASV), respectively, in the rhizospheric soil and roots of S. sclarea under TE-polluted conditions. Remarkably, 69 AMF species were detected at our experimental site, belonging to 12 AMF genera. Furthermore, the inoculation treatment significantly shaped the fungal communities in soil and increased the number of AMF ASVs in clary sage roots. In addition, clary sage cultivation over successive years could be one of the explanatory parameters for the inter-annual variation in both fungal and AMF communities in the soil and root biotopes. Our data provide new insights on fungal and AMF communities in the rhizospheric soil and roots of an aromatic plant, clary sage, grown in TE-polluted agricultural soil.

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Nonlegumes, Legumes, and Root Nodules Harbor Different Arbuscular Mycorrhizal Fungal Communities

Applied and Environmental Microbiology ◽

10.1128/aem.70.10.6240-6246.2004 ◽

2004 ◽

Vol 70 (10) ◽

pp. 6240-6246 ◽

Cited By ~ 186

Author(s):

Tanja R. Scheublin ◽

Karyn P. Ridgway ◽

J. Peter W. Young ◽

Marcel G. A. van der Heijden

Keyword(s):

Community Composition ◽

Plant Species ◽

Mycorrhizal Fungi ◽

Direct Sequencing ◽

Root Nodules ◽

Arbuscular Mycorrhizal ◽

Small Subunit ◽

Sequence Type ◽

Plant Functional Groups ◽

Amf Communities

ABSTRACT Legumes are an important plant functional group since they can form a tripartite symbiosis with nitrogen-fixing Rhizobium bacteria and phosphorus-acquiring arbuscular mycorrhizal fungi (AMF). However, not much is known about AMF community composition in legumes and their root nodules. In this study, we analyzed the AMF community composition in the roots of three nonlegumes and in the roots and root nodules of three legumes growing in a natural dune grassland. We amplified a portion of the small-subunit ribosomal DNA and analyzed it by using restriction fragment length polymorphism and direct sequencing. We found differences in AMF communities between legumes and nonlegumes and between legume roots and root nodules. Different plant species also contained different AMF communities, with different AMF diversity. One AMF sequence type was much more abundant in legumes than in nonlegumes (39 and 13%, respectively). Root nodules contained characteristic AMF communities that were different from those in legume roots, even though the communities were similar in nodules from different legume species. One AMF sequence type was found almost exclusively in root nodules. Legumes and root nodules have relatively high nitrogen concentrations and high phosphorus demands. Accordingly, the presence of legume- and nodule-related AMF can be explained by the specific nutritional requirements of legumes or by host-specific interactions among legumes, root nodules, and AMF. In summary, we found that AMF communities vary between plant functional groups (legumes and nonlegumes), between plant species, and between parts of a root system (roots and root nodules).

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Precipitation shapes communities of arbuscular mycorrhizal fungi in Tibetan alpine steppe

Scientific Reports ◽

10.1038/srep23488 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 30

Author(s):

Jing Zhang ◽

Fang Wang ◽

Rongxiao Che ◽

Ping Wang ◽

Hanke Liu ◽

...

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Community Composition ◽

Plant Species ◽

Mycorrhizal Fungi ◽

Environmental Changes ◽

Regional Scale ◽

Arbuscular Mycorrhizal ◽

Future Climate Change ◽

Alpine Steppe ◽

Amf Communities

Abstract Tibetan Plateau is one of the largest and most unique habitats for organisms including arbuscular mycorrhizal fungi (AMF). However, it remains unclear how AMF communities respond to key environmental changes in this harsh environment. To test if precipitation could be a driving force in shaping AMF community structures at regional scale, we examined AMF communities associated with dominant plant species along a precipitation gradient in Tibetan alpine steppe. Rhizosphere soils were collected from five sites with annual precipitation decreasing from 400 to 50 mm. A total of 31 AMF operational taxonomic units (OTUs) were identified. AMF community composition varied significantly among sites, whereas AMF community composition did not vary among plant species. Path analysis revealed that precipitation directly affected AMF hyphal length density, and indirectly influenced AMF species richness likely through the mediation of plant coverage. Our results suggested that water availability could drive the changes of AMF communities at regional scale. Given the important roles AMF could play in the dynamics of plant communities, exploring the changes of AMF communities along key environmental gradients would help us better predict the ecosystem level responses of the Tibetan vegetation to future climate change.

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Diverse and abundant arbuscular mycorrhizal fungi in ecological floating beds used to treat eutrophic water

10.21203/rs.3.rs-281997/v1 ◽

2021 ◽

Author(s):

Zhouying Xu ◽

Yichao Lv ◽

Yinghe Jiang ◽

Xiaodong Luo ◽

Xuelin Gui ◽

...

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Community Composition ◽

Plant Species ◽

Mycorrhizal Fungi ◽

Aquatic Ecosystems ◽

Species Abundance ◽

Arbuscular Mycorrhizal ◽

Eutrophic Lakes ◽

Amf Diversity ◽

Amf Communities

Abstract An increasing number of investigations have demonstrated the universal existence of arbuscular mycorrhizal fungi (AMF) in aquatic ecosystems. However, little is known about the accurate distribution and functions of AMF inhabiting aquatic ecosystems, especially ecological floating bed (EFB) which was constructed for the remediation of polluted waterbodies.In this study, we collected root samples of Canna generalis, Cyperus alternifolius and Eichhornia crassipes from three EFBs floating on two eutrophic lakes in Wuhan, China, to investigate the resources and distribution of AMF in EFBs using Illumina Mi-seq technology. A total of 229 operational taxonomic units (OTUs) and 21 taxon from 348,799 Glomeromycota sequences were detected. Glomus was the most dominant AMF in the three EFBs while the second dominant AMF was related to Acaulospora. Different aquatic plant species exhibited varying degrees of AMF colonization (3.83%~71%), diversity (6~103 OTUs, 3~15 virtual taxa) and abundance (14~57551 sequences). Low AMF abundance but relatively high AMF diversity were found in C. alternifolius which is usually considered as non-mycorrhizal, demonstrating the high accuracy of Illumina sequencing. In addition, results from this study suggested a lognormal species abundance distribution was observed across AMF taxa in the three plant species, and the AMF community composition was closely related to pH, nitrogen and phosphorus.Overall, our data demonstrated that diverse and abundant AMF communities were living in EFBs, and the AMF community composition was closely related to the water quality of eutrophic lakes treated by EFBs, providing potential possibility for the applications of AMF in plant-based bioremediation of wastewater.

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Disentangling nematode and arbuscular mycorrhizal fungal community effect on the growth of range-expanding Centaurea stoebe in original and new range soil

Plant and Soil ◽

10.1007/s11104-021-05020-w ◽

2021 ◽

Author(s):

Kadri Koorem ◽

Rutger A. Wilschut ◽

Carolin Weser ◽

Wim H. van der Putten

Keyword(s):

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Plant Performance ◽

Native Plant ◽

Soil Organisms ◽

Centaurea Stoebe ◽

Native Plant Species ◽

Soil Communities ◽

Plant Soil ◽

Amf Communities

Abstract Aims Numerous organisms show range expansions in response to current climate change. Differences in expansion rates, such as between plants and soil biota, may lead to altered interactions in the new compared to the original range. While plant-soil interactions influence plant performance and stress tolerance, the roles of specific soil organisms driving these responses remain unknown. Methods We manipulated the abundances of nematodes and arbuscular mycorrhizal fungi (AMF), collected from original and new range soils, and examined their effects on the biomass of range-expanding Centaurea stoebe and native Centaurea jacea. In the first approach, nematode and AMF communities were extracted from field soils, and inoculated to sterilized soil. In the second approach, the abundance of soil organisms in soil inocula was reduced by wet sieving; at first, plants were grown to condition the soil, and then plant-soil feedback was determined under ambient and drought conditions. Results The origin of soil communities did not influence the biomass production of range-expanding or native plant species, neither by addition nor by (partial) removal. However, after conditioning and under drought, range expanding C. stoebe produced more biomass with soil communities from the original range while C. jacea, native to both ranges, produced more biomass with new range soil communities. Conclusions We show that nematode and AMF communities from original and new range have similar effect on the growth of range expanding C. stoebe. Our results highlight that the effect of soil communities on plant growth increases after soil conditioning and under drought stress.

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Influence of Habitat and Climate Variables on Arbuscular Mycorrhizal Fungus Community Distribution, as Revealed by a Case Study of Facultative Plant Epiphytism under Semiarid Conditions

Applied and Environmental Microbiology ◽

10.1128/aem.02466-13 ◽

2013 ◽

Vol 79 (23) ◽

pp. 7203-7209 ◽

Cited By ~ 17

Author(s):

E. Torrecillas ◽

P. Torres ◽

M. M. Alguacil ◽

J. I. Querejeta ◽

A. Roldán

Keyword(s):

Community Composition ◽

Mycorrhizal Fungi ◽

Mycorrhizal Fungus ◽

Arbuscular Mycorrhizal ◽

Phoenix Dactylifera ◽

Mediterranean Ecosystems ◽

Climate Variables ◽

Content Type ◽

Fungal Propagules ◽

Amf Communities

ABSTRACTIn semiarid Mediterranean ecosystems, epiphytic plant species are practically absent, and only some species of palm trees can support epiphytes growing in their lower crown area, such asPhoenix dactyliferaL. (date palm). In this study, we focused onSonchus tenerrimusL. plants growing as facultative epiphytes inP. dactyliferaand its terrestrial forms growing in adjacent soils. Our aim was to determine the possible presence of arbuscular mycorrhizal fungi (AMF) in these peculiar habitats and to relate AMF communities with climatic variations. We investigated the AMF community composition of epiphytic and terrestrialS. tenerrimusplants along a temperature and precipitation gradient across 12 localities. Epiphytic roots were colonized by AMF, as determined by microscopic observation; all of the epiphytic and terrestrial samples analyzed showed AMF sequences from taxa belonging to the phylumGlomeromycota, which were grouped in 30 AMF operational taxonomic units. The AMF community composition was clearly different between epiphytic and terrestrial root samples, and this could be attributable to dispersal constraints and/or the contrasting environmental and ecophysiological conditions prevailing in each habitat. Across sites, the richness and diversity of terrestrial AMF communities was positively correlated with rainfall amount during the most recent growing season. In contrast, there was no significant correlation between climate variables and AMF richness and diversity for epiphytic AMF communities, which suggests that the composition of AMF communities in epiphytic habitats appears to be largely determined by the availability and dispersion of fungal propagules from adjacent terrestrial habitats.

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Possible role of arbuscular mycorrhizal fungi and associated bacteria in the recruitment of endophytic bacterial communities by plant roots

Mycorrhiza ◽

10.1007/s00572-021-01040-7 ◽

2021 ◽

Author(s):

Gergely Ujvári ◽

Alessandra Turrini ◽

Luciano Avio ◽

Monica Agnolucci

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Root System ◽

Bacterial Communities ◽

Mycorrhizal Fungi ◽

Plant Pathogens ◽

Plant Hormone ◽

Arbuscular Mycorrhizal ◽

Plant Performance ◽

Nutrient Mobilization ◽

Associated Bacteria

AbstractArbuscular mycorrhizal fungi (AMF) represent an important group of root symbionts, given the key role they play in the enhancement of plant nutrition, health, and product quality. The services provided by AMF often are facilitated by large and diverse beneficial bacterial communities, closely associated with spores, sporocarps, and extraradical mycelium, showing different functional activities, such as N2 fixation, nutrient mobilization, and plant hormone, antibiotic, and siderophore production and also mycorrhizal establishment promotion, leading to the enhancement of host plant performance. The potential functional complementarity of AMF and associated microbiota poses a key question as to whether members of AMF-associated bacterial communities can colonize the root system after establishment of mycorrhizas, thereby becoming endophytic. Root endophytic bacterial communities are currently studied for the benefits provided to host plants in the form of growth promotion, stress reduction, inhibition of plant pathogens, and plant hormone release. Their quantitative and qualitative composition is influenced by many factors, such as geographical location, soil type, host genotype, and cultivation practices. Recent data suggest that an additional factor affecting bacterial endophyte recruitment could be AMF and their associated bacteria, even though the mechanisms allowing members of AMF-associated bacterial communities to actually establish in the root system, becoming endophytic, remain to be determined. Given the diverse plant growth–promoting properties shown by AMF-associated bacteria, further studies are needed to understand whether AMF may represent suitable tools to introduce beneficial root endophytes in sustainable and organic agriculture where the functioning of such multipartite association may be crucial for crop production.

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Cooccurring Gentiana verna and Gentiana acaulis and Their Neighboring Plants in Two Swiss Upper Montane Meadows Harbor Distinct Arbuscular Mycorrhizal Fungal Communities

Applied and Environmental Microbiology ◽

10.1128/aem.00987-07 ◽

2007 ◽

Vol 73 (17) ◽

pp. 5426-5434 ◽

Cited By ~ 74

Author(s):

Zuzana Sýkorová ◽

Andres Wiemken ◽

Dirk Redecker

Keyword(s):

Host Plant ◽

Community Composition ◽

Plant Species ◽

Mycorrhizal Fungi ◽

Host Preference ◽

Arbuscular Mycorrhizal ◽

Major Influence ◽

Host Plant Species ◽

Amf Communities ◽

The Impact

ABSTRACT The community composition of arbuscular mycorrhizal fungi (AMF) was analyzed in roots of Gentiana verna, Gentiana acaulis, and accompanying plant species from two species-rich Swiss alpine meadows located in the same area. The aim of the study was to elucidate the impact of host preference or host specificity on the AMF community in the roots. The roots were analyzed by nested PCR, restriction fragment length polymorphism screening, and sequencing of ribosomal DNA small-subunit and internal transcribed spacer regions. The AMF sequences were analyzed phylogenetically and used to define monophyletic sequence types. The AMF community composition was strongly influenced by the host plant species, but compositions did not significantly differ between the two sites. Detailed analyses of the two cooccurring gentian species G. verna and G. acaulis, as well as of neighboring Trifolium spp., revealed that their AMF communities differed significantly. All three host plant taxa harbored AMF communities comprising multiple phylotypes from different fungal lineages. A frequent fungal phylotype from Glomus group B was almost exclusively found in Trifolium spp., suggesting some degree of host preference for this fungus in this habitat. In conclusion, the results indicate that within a relatively small area with similar soil and climatic conditions, the host plant species can have a major influence on the AMF communities within the roots. No evidence was found for a narrowing of the mycosymbiont spectrum in the two green gentians, in contrast to previous findings with their achlorophyllous relatives.

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Can root-associated fungi mediate the impact of abiotic conditions on the growth of a High Arctic herb?

10.1101/2020.06.20.157099 ◽

2020 ◽

Author(s):

Magdalena Wutkowska ◽

Dorothee Ehrich ◽

Sunil Mundra ◽

Anna Vader ◽

Pernille B. Eidesen

Keyword(s):

Community Composition ◽

Fungal Community ◽

Environmental Conditions ◽

Structural Equation ◽

Reproductive Investment ◽

High Arctic ◽

Plant Performance ◽

Fungal Community Composition ◽

Whole Plants ◽

The Impact

ABSTRACTArctic plants are affected by many stressors. Root-associated fungi are thought to influence plant performance in stressful environmental conditions. However, the relationships are not transparent; do the number of fungal partners, their ecological functions and community composition mediate the impact of environmental conditions and/or influence host plant performance? To address these questions, we used a common arctic plant as a model system: Bistorta vivipara. Whole plants (including root system) were collected from nine locations in Spitsbergen (n=214). Morphometric features were measured as a proxy for performance and combined with metabarcoding datasets of their root-associated fungi (amplicon sequence variants, ASVs), edaphic and meteorological variables. Seven biological hypotheses regarding fungal influence on plant measures were tested using structural equation modelling. The best-fitting model revealed that local temperature affected plants both directly (negatively aboveground and positively below-ground) and indirectly - mediated by fungal richness and the ratio of symbio- and saprotrophic ASVs. Fungal community composition did not impact plant measurements and plant reproductive investment did not depend on any fungal parameters. The lack of impact of fungal community composition on plant performance suggests that the functional importance of fungi is more important than their identity. The influence of temperature on host plants is therefore complex and should be examined further.

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