Arbuscular Mycorrhizal Fungal Communities in Organic and Conventional Onion Crops in the Columbia Basin of the Pacific Northwest United States

Onions are highly responsive to arbuscular mycorrhizal fungi (AMF), but little is known about AMF communities in onion crops (∼10,000 ha) in the semiarid, irrigated region of the Columbia Basin of Washington and Oregon. AMF communities and root colonization were compared in organic and conventional onion fields, and between paired conventional fields that were fumigated or not with metam sodium. AMF were detected in all fields at all sampling times, with no differences in root colonization of onions used to bait soil from organic versus conventional and fumigated versus nonfumigated fields. However, AMF colonization of roots of onion plants sampled midsummer was greater in organic versus conventional fields (67 versus 51%) and less in fumigated versus nonfumigated conventional fields (45 versus 67%). Pyrosequencing identified four AMF genera (Glomus, Claroideoglomus, Paraglomus, and Diversispora) and four dominant operational taxonomic units (OTUs) (Glomus mosseae (Funneliformis mosseae), Glomus Whitfield type 17, Claroideoglomus lamellosum, and Glomus MO_G17). AMF community structure in roots of onion plants collected from crops midsummer was different in organic versus conventional crops, with greater AMF diversity and richness in organic than conventional crops. There was no effect of organic versus conventional crops on dominant OTUs, but several low-abundance OTUs in organic fields were not detected in conventional fields. There was no consistent effect of metam sodium chemigation on AMF communities in onion crops. Overall, cropping practices in organic versus conventional onion production, and the use of metam sodium soil fumigation by center-pivot chemigation do not appear to be major drivers of AMF communities.

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Dynamics of arbuscular mycorrhizal fungi in relation to root colonization, spore density, and soil properties among different spreading stages of the exotic plant threeflower beggarweed (Desmodium triflorum) in a Zoysia tenuifolia lawn

Weed Science ◽

10.1017/wsc.2019.50 ◽

2019 ◽

Vol 67 (6) ◽

pp. 689-701

Author(s):

Xiaoge Han ◽

Changchao Xu ◽

Yutao Wang ◽

Dan Huang ◽

Qiang Fan ◽

...

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Soil Properties ◽

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Spore Density ◽

Invasive Weed ◽

Weed Invasion ◽

Operational Taxonomic Units ◽

Amf Communities ◽

Spore Densities

AbstractWeed invasion is a prevailing problem in modestly managed lawns. Less attention has been given to the exploration of the role of arbuscular mycorrhizal fungi (AMF) under different invasion pressures from lawn weeds. We conducted a four-season investigation into a Zoysia tenuifolia Willd. ex Thiele (native turfgrass)–threeflower beggarweed [Desmodium triflorum (L.) DC.] (invasive weed) co-occurring lawn. The root mycorrhizal colonizations of the two plants, the soil AM fungal communities and the spore densities under five different coverage levels of D. triflorum were investigated. Desmodium triflorum showed significantly higher root hyphal and vesicular colonizations than those of Z. tenuifolia, while the root colonizations of both species varied significantly among seasons. The increased coverage of D. triflorum resulted in the following effects: (1) the spore density initially correlated with mycorrhizal colonizations of Z. tenuifolia but gradually correlated with those of D. triflorum. (2) Correlations among soil properties, spore densities, and mycorrhizal colonizations were more pronounced in the higher coverage levels. (3) Soil AMF community compositions and relative abundances of AMF operational taxonomic units changed markedly in response to the increased invasion pressure. The results provide strong evidence that D. triflorum possessed a more intense AMF infection than Z. tenuifolia, thus giving rise to the altered host contributions to sporulation, soil AMF communities, relations of soil properties, spore densities, and root colonizations of the two plants, all of which are pivotal for the successful invasion of D. triflorum in lawns.

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Optimised nitrogen fertiliser management achieved higher diversity of arbuscular mycorrhiza fungi and high-yielding maize (Zea mays L.)

Crop and Pasture Science ◽

10.1071/cp14160 ◽

2015 ◽

Vol 66 (7) ◽

pp. 706 ◽

Cited By ~ 7

Author(s):

Xiaojing Wang ◽

Xinxin Wang ◽

Gu Feng

Keyword(s):

Zea Mays ◽

Mycorrhizal Fungi ◽

Zea Mays L ◽

Crop Yields ◽

Arbuscular Mycorrhizal ◽

Agricultural Landscapes ◽

High Rate ◽

Amf Diversity ◽

Intensively Managed ◽

Amf Communities

The integrated soil–crop system management (ISSM) approach can potentially mitigate the loss of biodiversity in agricultural landscapes, ensuring crop yield with lower nitrogen (N) fertiliser input and minimised environmental pollution. The aim of this study was to test the hypotheses that overuse of N fertiliser could reduce the biodiversity of arbuscular mycorrhizal fungi (AMF) and that ISSM could help to maintain higher AMF biodiversity than the conventionally managed system in maize (Zea mays L.). The AMF community composition under three different treatments (conventionally managed, N-optimised and non-N-fertilised fields) was assessed by using both spore-based morphological taxonomy and DNA-based T-RFLP fingerprinting approaches. Maize roots in intensively managed fields formed functioning mycorrhizal symbioses even when a high rate of N fertiliser was applied. AMF diversity was higher under optimised N input, whereas AMF richness decreased when more N fertiliser was used. The N-optimised farms had AMF communities similar to those in the conventionally managed fields. The ISSM approach is recommended for sustaining crop yields without incurring continuing environmental costs and for maintaining AMF communities in intensively managed agro-ecosystems, especially in rapidly developing countries.

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Inoculation with highly-related mycorrhizal fungal siblings, and their interaction with plant genoptypes, strongly shapes tropical mycorrhizal fungal community structure

10.1101/2020.07.31.230490 ◽

2020 ◽

Author(s):

Yuli Marcela Ordoñez ◽

Lucas Villard ◽

Isabel Ceballos ◽

Frédéric G Masclaux ◽

Alia Rodriguez ◽

...

Keyword(s):

Community Structure ◽

Mycorrhizal Fungi ◽

Crop Yields ◽

Arbuscular Mycorrhizal ◽

Tropical Soils ◽

Mycorrhizal Symbiosis ◽

Fungal Community Structure ◽

Amf Diversity ◽

Amf Communities ◽

The Impact

Arbuscular mycorrhizal fungi (AMF) have the potential to increase crop yields and all globally important crops form the mycorrhizal symbiosis. Only a few studies have investigated the impact of introduced AMF on local AMF communities and most studies have only investigated effects of one isolate. We studied the impact on AMF community structure of inoculating roots of the globally important crop cassava with highly genetically-related clonal siblings of two genetically different Rhizophagus irregularis isolates. We hypothesized that inoculation with R. irregularis siblings differentially influences the structure and the diversity of the pre-existing AMF community colonizing cassava. Alpha and beta taxonomic and phylogenetic AMF diversity were strongly and significantly altered differentially following inoculation with sibling AMF progeny. In most cases, the effects were also cassava-genotype specific. Although biomass production and AMF colonization were also both differentially affected by inoculation with sibling R. irregularis progeny these variables were not correlated with changes in the AMF community structure. The results highlight that investigations on the impact of an introduced AMF species, that use only one isolate, are unlikely to be representative of the overall effects of that AMF species and that the genetic identity of the host must be considered. The amount of inoculum added was very small and effects were observed 12 months following inoculation. That such a small amount of almost genetically identical fungal inoculum can strongly differentially influence AMF community structure 12 months following inoculation, indicates that AMF communities in tropical soils are not very resistant to perturbation.

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Succession of endophytic fungi and arbuscular mycorrhizal fungi associated with the growth of plant and their correlation with secondary metabolites in the roots of plants

BMC Plant Biology ◽

10.1186/s12870-021-02942-6 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Hanli Dang ◽

Tao Zhang ◽

Zhongke Wang ◽

Guifang Li ◽

Wenqin Zhao ◽

...

Keyword(s):

Secondary Metabolites ◽

Arbuscular Mycorrhizal Fungi ◽

Endophytic Fungi ◽

Relative Abundance ◽

Mycorrhizal Fungi ◽

Growth Period ◽

Arbuscular Mycorrhizal ◽

Amf Diversity ◽

Metabolite Accumulation ◽

Amf Communities

Abstract Background To decipher the root and microbial interaction, secondary metabolite accumulation in roots and the microbial community’s succession model during the plant’s growth period demands an in-depth investigation. However, till now, no comprehensive study is available on the succession of endophytic fungi and arbuscular mycorrhizal fungi (AMF) with roots of medicinal licorice plants and the effects of endophytic fungi and AMF on the secondary metabolite accumulation in licorice plant’s root. Results In the current study, interaction between root and microbes in 1–3 years old medicinal licorice plant’s root and rhizospheric soil was investigated. Secondary metabolites content in licorice root was determined using high-performance liquid chromatography (HPLC). The composition and diversity of endophytic and AMF in the root and soil were deciphered using high-throughput sequencing technology. During the plant’s growth period, as compared to AMF, time and species significantly affected the diversity and richness of endophytic fungi, such as Ascomycota, Basidiomycota, Fusarium, Cladosporium, Sarocladium. The growth period also influenced the AMF diversity, evident by the significant increase in the relative abundance of Glomus and the significant decrease in the relative abundance of Diversispora. It indicated a different succession pattern between the endophytic fungal and AMF communities. Meanwhile, distance-based redundancy analysis and Mantel tests revealed root’s water content and secondary metabolites (glycyrrhizic acid, liquiritin, and total flavonoids), which conferred endophytic fungi and AMF diversity. Additionally, plant growth significantly altered soil’s physicochemical properties, which influenced the distribution of endophytic fungal and AMF communities. Conclusions This study indicated a different succession pattern between the endophytic fungal and AMF communities. During the plant’s growth period, the contents of three secondary metabolites in roots increased per year, which contributed to the overall differences in composition and distribution of endophytic fungal and AMF communities. The endophytic fungal communities were more sensitive to secondary metabolites than AMF communities. The current study provides novel insights into the interaction between rhizospheric microbes and root exudates.

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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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Diversity of Arbuscular Mycorrhizal Fungi in Agroforestry, Conventional Plantations and Native Forests in Roraima State, Northern Brazil

Journal of Agricultural Science ◽

10.5539/jas.v11n14p282 ◽

2019 ◽

Vol 11 (14) ◽

pp. 282 ◽

Cited By ~ 1

Author(s):

Tharles Mesquita Araújo ◽

Krisle da Silva ◽

Gilmara Maria Duarte Pereira ◽

Alexandre Curcino ◽

Sidney Luiz Stürmer ◽

...

Keyword(s):

Species Richness ◽

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Terrestrial Ecosystems ◽

Agroforestry System ◽

Native Forest ◽

Amf Diversity ◽

Amf Communities ◽

Land Use And Management

Arbuscular mycorrhizal fungi (AMF) are important components of the soil microbiota in terrestrial ecosystems, under the influence of various factors such as soil use and management, and can be adapted to a structure and diversity of fungal communities. The aim of this survey was to evaluate the influence of different systems of land use and management on AMF diversity in the Roraima State, Brazil. We collected soil samples in agroforestry, conventional soybean planting, conventional corn and native forest. After 150 days of incubation in a greenhouse, we extracted the spores in order to evaluate AMF, volume and to determine taxonomic identification. We found 16 species of AMF and the genus Acaulospora was the most frequent, followed by Glomus. Soil under agroforestry system had the highest species richness and the native forest, the lowest. On the other hand, soybean and corn areas presented greater density values than agroforestry system and native forest. In the agroforestry system, SOM attributes, Al3+ and H + Al had influence in AMF species richness. Thus, agroforestry constitute sustainable alternative influencing AMF communities in these ecosystems.

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The herbaceous landlord: integrating the effects of symbiont consortia within a single host

PeerJ ◽

10.7717/peerj.1379 ◽

2015 ◽

Vol 3 ◽

pp. e1379 ◽

Cited By ~ 12

Author(s):

Roo Vandegrift ◽

Bitty A. Roy ◽

Laurel Pfeifer-Meister ◽

Bart R. Johnson ◽

Scott D. Bridgham

Keyword(s):

Pacific Northwest ◽

Mycorrhizal Fungi ◽

Systems Approach ◽

Arbuscular Mycorrhizal ◽

Climatic Conditions ◽

The Pacific ◽

Single Host ◽

Fungal Associates ◽

The Individual ◽

Climate Manipulation

Plants are typically infected by a consortium of internal fungal associates, including endophytes in their leaves, as well as arbuscular mycorrhizal fungi (AMF) and dark septate endophytes (DSE) in their roots. It is logical that these organisms will interact with each other and the abiotic environment in addition to their host, but there has been little work to date examining the interactions of multiple symbionts within single plant hosts, or how the relationships among symbionts and their host change across environmental conditions. We examined the grassAgrostis capillarisin the context of a climate manipulation experiment in prairies in the Pacific Northwest, USA. Each plant was tested for presence of foliar endophytes in the genusEpichloë, and we measured percent root length colonized (PRLC) by AMF and DSE. We hypothesized that the symbionts in our system would be in competition for host resources, that the outcome of that competition could be driven by the benefit to the host, and that the host plants would be able to allocate carbon to the symbionts in such a way as to maximize fitness benefit within a particular environmental context. We found a correlation between DSE and AMF PRLC across climatic conditions; we also found a fitness cost to increasing DSE colonization, which was negated by presence ofEpichloëendophytes. These results suggest that selective pressure on the host is likely to favor host/symbiont relationships that structure the community of symbionts in the most beneficial way possible for the host, not necessarily favoring the individual symbiont that is most beneficial to the host in isolation. These results highlight the need for a more integrative, systems approach to the study of host/symbiont consortia.

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Subsoil arbuscular mycorrhizal fungal communities in arable soil differ from those in topsoil

10.1101/212597 ◽

2017 ◽

Author(s):

Moisés A. Sosa-Hernández ◽

Julien Roy ◽

Stefan Hempel ◽

Timo Kautz ◽

Ulrich Köpke ◽

...

Keyword(s):

Community Structure ◽

Mycorrhizal Fungi ◽

Potential Role ◽

Arbuscular Mycorrhizal ◽

Fungal Communities ◽

Operational Taxonomic Units ◽

Family Level ◽

Amf Communities ◽

Arbuscular Mycorrhizal Fungal

AbstractArbuscular mycorrhizal fungi are recognized as important drivers of plant health and productivity in agriculture but very often existing knowledge is limited to the topsoil. With growing interest in the role of subsoil in sustainable agriculture, we used high-throughput Illumina sequencing on a set of samples encompassing drilosphere, rhizosphere and bulk soil, in both top- and subsoil. Our results show subsoil AMF communities harbor unique Operational Taxonomic Units (OTUs) and that both soil depths differ in community structure both at the OTU and family level. Our results emphasize the distinctness of subsoil AMF communities and the potential role of subsoil as a biodiversity reservoir.

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The composition and diversity of arbuscular mycorrhizal fungi in karst soils and roots collected from mulberry of different ages

Ciência Rural ◽

10.1590/0103-8478cr20180361 ◽

2018 ◽

Vol 48 (10) ◽

Cited By ~ 1

Author(s):

Dan Xing ◽

Zhenhong Wang ◽

Jiujun Xiao ◽

Shiyu Han ◽

Chaobin Luo ◽

...

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Critical Role ◽

454 Sequencing ◽

Arbuscular Mycorrhizal ◽

Soil Environment ◽

Environment Change ◽

Amf Diversity ◽

Root Sample ◽

Amf Communities

ABSTRACT: Arbuscular mycorrhizal fungi (AMF) have been attracted more scientific attentions due to its critical role in enhancement of drought tolerance of plants for growth and vegetation restoration in karst fragile ecosystem. However, scientists know little about the AMF composition and diversity occurring in root systems of mulberry (Morus sp.), and in karst habitats which return land use from mulberry forestry, as well as the effects of soil environment change on the diversity of the AMF communities. To understand: (1) the AMF community composition and diversity at different stage of returning cropland to forest; and (2) the effects of soil environment change on the diversity of the AMF communities, soil and mulberry root samples were collected from Bijie and Libo sites, China, which experienced one and ten years, respectively, after returning croplands to forest. With the high throughput 454-sequencing technology, 8 known genera including 83 virtual species were distinguished and the genera Glomus, Paraglomus, Archaeospora and Diversispora were found to be dominant in soil and root sample. Compared to the samples in Libo, the genera Glomus, Paraglomus, Acaulospora and Claroideoglomus in root samples at Bijie site had a relatively abundance of species indicating that the returning cropland to forest is benefit to the AMF diversity and abundance, which was attribute to the variation of soil physiochemical properties. This conclusion is of great significance for guiding the return of farmland to forests.

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Impact of Phosphorus Fertilization on Tomato Growth and Arbuscular Mycorrhizal Fungal Communities

Microorganisms ◽

10.3390/microorganisms8020178 ◽

2020 ◽

Vol 8 (2) ◽

pp. 178 ◽

Cited By ~ 4

Author(s):

Masao Higo ◽

Mirai Azuma ◽

Yusuke Kamiyoshihara ◽

Akari Kanda ◽

Yuya Tatewaki ◽

...

Keyword(s):

Mycorrhizal Fungi ◽

Root Colonization ◽

Plant Biomass ◽

Arbuscular Mycorrhizal ◽

Phosphorus Fertilization ◽

P Fertilization ◽

Tomato Plants ◽

P Fertilizer ◽

Amf Communities ◽

The Impact

Understanding the impact of phosphorus (P) addition on arbuscular mycorrhizal fungi (AMF) is crucial to understanding tomato (Solanum lycopersicum L.) P nutrition. However, it remains unknown how P fertilization is associated with the structure of AMF communities on tomato plants. Thus, we investigated whether levels of P fertilizer interacted with the colonization and structure of AMF in tomato roots in a field trial. In this study, we established three different amounts of P fertilizer treatments (0 kg ha−1, 50 kg ha−1, and 100 kg ha−1). We investigated AMF root colonization and community structure, as well as plant growth in tomatoes at seven weeks following transplantation. The structure of the AMF communities in the roots of tomato were determined by MiSeq amplicon sequencing. As expected, P fertilizer input enhanced the P uptake and plant biomass. In contrast, the P fertilizer level did not affect the AMF root colonization and diversity or the structure of the AMF communities in the tomato. However, we found a negative correlation between AMF colonization and richness in the roots of the tomato plants. Therefore, we need to investigate whether and how AMF communities and P fertilization develop more effective P management for tomato plants.

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