406 Plant Diversity Influences Effectiveness of Associated Arbuscular–Mycorrhizal Fungi

Growing a plant host in association with other plant species (i.e., increasing diversity) changes the composition of the associated arbuscular–mycorrhizal (AM) fungal community. We tested whether this alteration in the fungal community causes significant differences in the growth of Schizachyrium scoparium L. (Little Bluestem, a C4 grass) or Lespedeza capitata L. (Bush clover, a legume). Seedlings were transplanted into pasteurized soil inoculated with soil from monoculture plots of Schizachyrium or Lespedeza, respectively, vs. plots containing one, seven, or 15 additional plant species. Soil washes from a composite of the plots were added to all pots, including non-inoculated controls, to reduce differences in the non-AM microbial communities. Spore counts of the inoculum from Lespedeza plots showed increasing numbers of AM fungal spores and species richness with increasing plant diversity; this was not true with the Schizachyrium plots, possibly because Schizachyrium may be a better host to more species of AM fungi than Lespedeza. Both Schizachyrium and Lespedeza responded to inoculation with increased growth compared to non-inoculated controls. Tissue analyses of both species showed that inoculation increased the percentage of Cu, and lowered the percentage of Mn compared to control plants. Schizachyrium showed no significant differences in growth due to inoculum source (1-, 2-, 8-, or 16-species plots); while Lespedeza showed increases in root and shoot weights with increasing source-plot diversity.

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Synergistic community responses of plants and arbuscular mycorrhizal fungi to extreme droughts in a cold-temperate grassland

10.22541/au.160635429.93596387/v1 ◽

2020 ◽

Author(s):

Wei Fu ◽

Baodong Chen ◽

Matthias Rillig ◽

Wang Ma ◽

Chong Xu ◽

...

Keyword(s):

Fungal Community ◽

Mycorrhizal Fungi ◽

Community Dynamics ◽

Environmental Changes ◽

Environmental Filtering ◽

Climate Extremes ◽

Arbuscular Mycorrhizal ◽

Am Fungi ◽

Temperate Grassland ◽

Community Responses

Mutualistic associations between plants and arbuscular mycorrhizal (AM) fungi may have profound influences on their response to climate changes. Existing theories evaluate the effects of interdependency and environmental filtering on plant-AM fungal community dynamics separately; however, abrupt environmental changes such as climate extremes can provoke duo-impacts on the metacommunity simultaneously. Here, we experimentally tested the relevance of plant and AM fungal community responses to extreme drought (chronic or intense) in a cold temperate grassland. Irrespective of drought intensities, plant species richness and productivity responses were significantly and positively correlated with AM fungal richness and also served as best predictors of AM fungal community shifts. Notably, the robustness of this community synergism increased with drought intensity, likely reflecting increased community interdependence. Network analysis showed a key role of Glomerales in AM fungal interaction with plants, suggesting specific plant-AM fungal pairing. Thus, community interdependence may underpin climate change impact on plant-AM fungal diversity patterns in grasslands.

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Stable C and N isotope natural abundances of intraradical hyphae of arbuscular mycorrhizal fungi

Mycorrhiza ◽

10.1007/s00572-020-00981-9 ◽

2020 ◽

Vol 30 (6) ◽

pp. 773-780

Author(s):

Saskia Klink ◽

Philipp Giesemann ◽

Timo Hubmann ◽

Johanna Pausch

Keyword(s):

Mycorrhizal Fungi ◽

Isotope Composition ◽

Fungal Spores ◽

Arbuscular Mycorrhizal ◽

Am Fungi ◽

Mineral Nutrient ◽

Carbohydrate Source ◽

Lipid Source ◽

Am Fungus ◽

C And N

Abstract Data for stable C and N isotope natural abundances of arbuscular mycorrhizal (AM) fungi are currently sparse, as fungal material is difficult to access for analysis. So far, isotope analyses have been limited to lipid compounds associated with fungal membranes or storage structures (biomarkers), fungal spores and soil hyphae. However, it remains unclear whether any of these components are an ideal substitute for intraradical AM hyphae as the functional nutrient trading organ. Thus, we isolated intraradical hyphae of the AM fungus Rhizophagus irregularis from roots of the grass Festuca ovina and the legume Medicago sativa via an enzymatic and a mechanical approach. In addition, extraradical hyphae were isolated from a sand-soil mix associated with each plant. All three approaches revealed comparable isotope signatures of R. irregularis hyphae. The hyphae were 13C- and 15N-enriched relative to leaves and roots irrespective of the plant partner, while they were enriched only in 15N compared with soil. The 13C enrichment of AM hyphae implies a plant carbohydrate source, whereby the enrichment was likely reduced by an additional plant lipid source. The 15N enrichment indicates the potential of AM fungi to gain nitrogen from an organic source. Our isotope signatures of the investigated AM fungus support recent findings for mycoheterotrophic plants which are suggested to mirror the associated AM fungi isotope composition. Stable isotope natural abundances of intraradical AM hyphae as the functional trading organ for bi-directional carbon-for-mineral nutrient exchanges complement data on spores and membrane biomarkers.

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Trait-based aerial dispersal of arbuscular mycorrhizal fungi

10.1101/2020.02.12.943878 ◽

2020 ◽

Author(s):

V. Bala Chaudhary ◽

Sarah Nolimal ◽

Moisés A. Sosa-Hernández ◽

Cameron Egan ◽

Jude Kastens

Keyword(s):

Community Structure ◽

Mycorrhizal Fungi ◽

High Throughput Sequencing ◽

Fungal Spores ◽

Arbuscular Mycorrhizal ◽

Am Fungi ◽

Global Scale ◽

Arbuscular Mycorrhizas ◽

List Type ◽

Aerial Dispersal

SUMMARYDispersal is a key process driving local-scale community assembly and global-scale biogeography of plant symbiotic arbuscular mycorrhizal (AM) fungal communities. A trait-based approach could improve predictions regarding how AM fungal aerial dispersal varies by species.We conducted month-long collections of aerial AM fungi for 12 consecutive months in an urban mesic environment at heights of 20 m. We measured functional traits of all collected spores and assessed aerial AM fungal community structure both morphologically and with high-throughput sequencing.Large numbers of AM fungal spores were present in the air over the course of one year and these spores were more likely to exhibit traits that facilitate dispersal. Aerial spores were smaller than average for Glomeromycotinan fungi. Trait-based predictions indicate that nearly 1/3 of described species from diverse genera demonstrate the potential for aerial dispersal. Diversity of aerial AM fungi was relatively high (20 spore species and 17 virtual taxa) and both spore abundance and community structure shifted temporally.The prevalence of aerial dispersal in arbuscular mycorrhizas is perhaps greater than previously indicated and a hypothesized model of AM fungal dispersal mechanisms is presented. Anthropogenic soil impacts may initiate the dispersal of disturbance-tolerating AM fungal species and facilitate community homogenization.

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Ecological interaction of little bluestem and vesicular–arbuscular mycorrhizal fungi

Canadian Journal of Botany ◽

10.1139/b84-309 ◽

1984 ◽

Vol 62 (11) ◽

pp. 2272-2277 ◽

Cited By ~ 29

Author(s):

Laura A. Dickman ◽

Anthony E. Liberta ◽

Roger C. Anderson

Keyword(s):

Soil Moisture ◽

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Schizachyrium Scoparium ◽

Sample Collection ◽

Little Bluestem ◽

Acaulospora Laevis ◽

Vesicular Arbuscular ◽

Vam Colonization ◽

Hill Prairie

The percentage of vesicular–arbuscular mycorrhizal (VAM) colonization of little bluestem (Schizachyrium scoparium) (Michx.) Nash.) and VAM spore populations in the rhizosphere of little bluestem from four prairie areas in Illinois were studied. At Goose Lake Prairie, a significant positive correlation (r = 0.77, p < 0.01) was found between soil moisture and density of VAM spores, but soil moisture and percent VAM colonization were not significantly correlated at any of its sites. Percentage of VAM colonization tended to be higher at study areas where little bluestem was a dominant species. However, spore numbers and abundance of little bluestem tended to be inversely related. Colonization decreased from May to July at all areas and this trend frequently continued into September. Month of sample collection had no significant effect on spore numbers except at Reavis Hill Prairie. The endophyte isolated at all areas was Glomus fasciculatum (Thaxter sensu Gerd.) Gerd. & Trappe. Other species, such as Gigaspora heterogama (Nicol. & Gerd.) Gerd. & Trappe and Acaulospora laevis Gerd. & Trappe, were more restricted in their distribution.

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Arbuscular Mycorrhizal Fungi Enhance Plant Diversity, Density and Productivity of Spring Ephemeral Community in Desert Ecosystem

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha45110766 ◽

2017 ◽

Vol 45 (1) ◽

pp. 301-307 ◽

Cited By ~ 1

Author(s):

Zhaoyong SHI ◽

Yongming WANG ◽

Shouxia XU ◽

Zhijian LAN ◽

Bede S. MICKAN ◽

...

Keyword(s):

Species Diversity ◽

Plant Diversity ◽

Mycorrhizal Fungi ◽

Plant Density ◽

Arbuscular Mycorrhizal ◽

Am Fungi ◽

Desert Ecosystem ◽

Spore Density ◽

Functional Study ◽

Soil Cores

Arbuscular mycorrhizal (AM) fungi form intimate associations with the roots of about 85% of all terrestrial plants, and can greatly increase a plant’s uptake of soil nutrients and have been shown to influence plant diversity in several ecosystems. A lot of studies have reported the effect of arbuscular mycorrhizas on plant density, species diversity, richness and productivity in desert herbland in Gurbantonggut desert, China. Here, we conduct a mycorrhizal functional study by suppressing AM fungi by applying the fungicide benomyl as a soil drench in soil cores and field in-situ experiment. The mycorrhiza-responsiveness of the dominant species Erodium oxyrrhynchum is assessed in intact soil cores containing the indigenous AM fungi. The soil-cores experiment displayed E. oxyrrhynchum to have a significant positive shoot and root growth response, and this is in response to the abundance of the indigenous AM fungal colonisation. The field experiment indicates the total aboveground dry biomass is negatively influenced by the suppression of AM fungi, though, no significant effect produced in the dominant and common plant species. The fungal suppression also affected density, species diversity and richness. The density of non-mycorrhizal plant Alyssum linifolium increases significantly in the treatment of suppressed AM fungi. The spore density decreases significantly in benomyl-treated plots. Our results showed that AM fungi were very important in desert ecosystem for the maintaining of plant biodiversity, richness and productivity.

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Arbuscular Mycorrhizal Fungi from Argentinean Highland Puna Soils Unveiled by Propagule Multiplication

Plants ◽

10.3390/plants10091803 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1803

Author(s):

Fernanda Covacevich ◽

Keren Hernández Guijarro ◽

Esteban M. Crespo ◽

Erica Lumini ◽

María Soledad Rivero Mega ◽

...

Keyword(s):

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Am Fungi ◽

Single Strand Conformation Polymorphism ◽

Polymorphism Analysis ◽

Indigenous Species ◽

Plant Host ◽

Generalist Species ◽

Morphological Approach ◽

Almost All

Low arbuscular-mycorrhizal (AM) sporulation in arid field soils limits our knowledge of indigenous species when diversity studies are based only on spore morphology. Our aim was to use different approaches (i.e., spore morphological approach and PCR–SSCP (single-strand-conformation-polymorphism) analysis after trap plant multiplication strategies to improve the knowledge of the current richness of glomalean AM fungi (Glomerales; Glomeromycota) from the Argentine Puna. Indigenous propagules from two pristine sites at 3870 and 3370 m of elevation were multiplied using different host plants; propagation periods (2–6 months), and subculture cycles (1; 2; or 3) from 5 to 13 months. The propagule multiplication experiment allowed the detection of different glomoid taxa of Funneliformis spp. and Rhizoglomus spp., which were considered cryptic species since they had never been found in Puna soils before. On the other hand; almost all the generalist species previously described were recovered from cultures; except for Glomus ambisporum. Both plant host selection and culture times are critical for Glomerales multiplication. The SSCP analysis complemented the morphological approach and showed a high variability of Glomus at each site; revealing the presence of Funneliformis mosseae. This study demonstrates that AMF trap culture (TC) is a useful strategy for improving the analysis of AM fungal diversity/richness in the Argentinean highlands.

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Diversity of arbuscular mycorrhizal fungi in soil from the Pampa Ondulada, Argentina, assessed by pyrosequencing and morphological techniques

Canadian Journal of Microbiology ◽

10.1139/cjm-2014-0364 ◽

2014 ◽

Vol 60 (12) ◽

pp. 819-827 ◽

Cited By ~ 12

Author(s):

R.P. Colombo ◽

L. Fernández Bidondo ◽

V.A. Silvani ◽

M.B. Carbonetto ◽

N. Rascovan ◽

...

Keyword(s):

Fungal Community ◽

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Am Fungi ◽

Operational Taxonomic Units ◽

Agronomic Practices ◽

Β Diversity ◽

Agronomic Management ◽

Negative Effect ◽

Morphological Species

The aim of this study was to assess the effects of agronomic practices on the arbuscular mycorrhizal (AM) fungal community in soils from the Pampa Ondulada region (Argentina), and to compare conclusions reached when using pyrosequencing or a morphological approach. The AM fungal diversity of 3 agricultural exploitations located in the Pampa Ondulada region (Argentina) was assessed by using 454 amplicon pyrosequencing and morphological (based on spore traits) approaches. Two kinds of soil managements are found in these sites: agronomic and non-agronomic. A total of 188 molecular operational taxonomic units and 29 morphological species of AM fungi were identified. No effect of soil management on AM richness was detected. AM fungal communities were more diverse and equitable in the absence of agronomic management. In contrast, the results on β-diversity varied according to the methodology used. We concluded that agronomic management of soil has a negative effect on AM fungal community biodiversity in the Pampa Ondulada region. We also conclude that both methodologies complement each other in the study of AM fungal ecology. This study greatly improved the knowledge about AM fungi in South America where the molecular diversity of AM fungi was practically unknown.

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Differences in Arbuscular Mycorrhizal Fungi among Three Coffee Cultivars in Puerto Rico

ISRN Agronomy ◽

10.5402/2012/148042 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 4

Author(s):

Ligia Lebrón ◽

D. Jean Lodge ◽

Paul Bayman

Keyword(s):

Puerto Rico ◽

Mycorrhizal Fungi ◽

Fungal Spores ◽

Arbuscular Mycorrhizal ◽

Am Fungi ◽

Spore Density ◽

Mycorrhizal Symbiosis ◽

Hyphal Length ◽

P Content ◽

Mycorrhizal Interactions

Mycorrhizal symbiosis is important for growth of coffee (Coffea arabica), but differences among coffee cultivars in response to mycorrhizal interactions have not been studied. We compared arbuscular mycorrhizal (AM) extraradical hyphae in the soil and diversity of AM fungi among three coffee cultivars, Caturra, Pacas, and Borbón, at three farms in Puerto Rico. Caturra had significantly lower total extraradical AM hyphal length than Pacas and Borbón at all locations. P content did not differ among cultivars. Extraradical hyphal lengths differed significantly among locations. Although the same morphotypes of mycorrhizal fungal spores were present in the rhizosphere of the three cultivars and total spore density did not differ significantly, frequencies of spore morphotypes differed significantly among cultivars. Spore morphotypes were typical of Glomus and Sclerocystis. Levels of soil nutrients did not explain differences in AM colonzation among cultivars. The cultivar Caturra is a mutant of Borbón and has apparently lost Borbón’s capacity to support and benefit from an extensive network of AM hyphae in the soil. Widespread planting of Caturra, which matures earlier and has higher yield if fertilized, may increase dependence on fertilizers.

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Hormonomic Changes Driving the Negative Impact of Broomrape on Plant Host Interactions with Arbuscular Mycorrhizal Fungi

International Journal of Molecular Sciences ◽

10.3390/ijms222413677 ◽

2021 ◽

Vol 22 (24) ◽

pp. 13677

Author(s):

Kiril Mishev ◽

Petre I. Dobrev ◽

Jozef Lacek ◽

Roberta Filepová ◽

Bistra Yuperlieva-Mateeva ◽

...

Keyword(s):

Host Plant ◽

Mycorrhizal Fungi ◽

Negative Impact ◽

Dominant Role ◽

Arbuscular Mycorrhizal ◽

Am Fungi ◽

Parasitic Plants ◽

Plant Roots ◽

Plant Host ◽

Mycorrhizal Roots

Belowground interactions of plants with other organisms in the rhizosphere rely on extensive small-molecule communication. Chemical signals released from host plant roots ensure the development of beneficial arbuscular mycorrhizal (AM) fungi which in turn modulate host plant growth and stress tolerance. However, parasitic plants have adopted the capacity to sense the same signaling molecules and to trigger their own seed germination in the immediate vicinity of host roots. The contribution of AM fungi and parasitic plants to the regulation of phytohormone levels in host plant roots and root exudates remains largely obscure. Here, we studied the hormonome in the model system comprising tobacco as a host plant, Phelipanche spp. as a holoparasitic plant, and the AM fungus Rhizophagus irregularis. Co-cultivation of tobacco with broomrape and AM fungi alone or in combination led to characteristic changes in the levels of endogenous and exuded abscisic acid, indole-3-acetic acid, cytokinins, salicylic acid, and orobanchol-type strigolactones. The hormonal content in exudates of broomrape-infested mycorrhizal roots resembled that in exudates of infested non-mycorrhizal roots and differed from that observed in exudates of non-infested mycorrhizal roots. Moreover, we observed a significant reduction in AM colonization of infested tobacco plants, pointing to a dominant role of the holoparasite within the tripartite system.

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Native soil amendments combined with commercial arbuscular mycorrhizal fungi increase biomass of Panicum amarum

Scientific Reports ◽

10.1038/s41598-021-97307-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Noah C. Luecke ◽

Austin J. Mejia ◽

Kerri M. Crawford

Keyword(s):

Mycorrhizal Fungi ◽

Soil Amendments ◽

Fungal Spores ◽

Arbuscular Mycorrhizal ◽

Am Fungi ◽

Plant Performance ◽

Ecosystem Functions ◽

Native Soil ◽

Panicum Amarum ◽

Native Soils

AbstractCoastal dune restorations often fail because of poorly performing plants. The addition of beneficial microbes can improve plant performance, though it is unclear if the source of microbes matters. Here, we tested how native soil amendments and commercially available arbuscular mycorrhizal (AM) fungi influenced performance of Panicum amarum, a dominant grass on Texas coastal dunes. In a greenhouse experiment, we manipulated the identity of native soil amendments (from P. amarum, Uniola paniculata, or unvegetated areas), the presence of soil microbes in the native soil amendments (live or sterile), and the presence of the commercial AM fungi (present or absent). Native soils from vegetated areas contained 149% more AM fungal spores than unvegetated areas. The commercial AM fungi, when combined with previously vegetated native soils, increased aboveground biomass of P. amarum by 26%. Effects on belowground biomass were weaker, although the addition of any microbes decreased the root:shoot ratio. The origin of native soil amendments can influence restoration outcomes. In this case soil from areas with vegetation outperformed soil from areas without vegetation. Combining native soils with commercial AM fungi may provide a strategy for increasing plant performance while also maintaining other ecosystem functions provided by native microbes.

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