Composition of Rhizosphere Microbial Communities Associated With Healthy and Verticillium Wilt Diseased Cotton Plants

Rhizosphere microbial communities are known to be related to plant health; using such an association for crop management requires a better understanding of this relationship. We investigated rhizosphere microbiomes associated with Verticillium wilt symptoms in two cotton cultivars. Microbial communities were profiled by amplicon sequencing, with the total bacterial and fungal DNA quantified by quantitative polymerase chain reaction based on the respective 16S and internal transcribed spacer primers. Although the level of V. dahliae inoculum was higher in the rhizosphere of diseased plants than in the healthy plants, such a difference explained only a small proportion of variation in wilt severities. Compared to healthy plants, the diseased plants had much higher total fungal/bacterial biomass ratio, as represented by quantified total fungal or bacterial DNA. The variability in the fungal/bacterial biomass ratio was much smaller than variability in either fungal or bacterial total biomass among samples within diseased or healthy plants. Diseased plants generally had lower bacterial alpha diversity in their rhizosphere, but such differences in the fungal alpha diversity depended on cultivars. There were large differences in both fungal and bacterial communities between diseased and healthy plants. Many rhizosphere microbial groups differed in their abundance between healthy and diseased plants. There was a decrease in arbuscular mycorrhizal fungi and an increase in several plant pathogen and saprophyte guilds in diseased plants. These findings suggested that V. dahliae infection of roots led to considerable changes in rhizosphere microbial communities, with large increases in saprophytic fungi and reduction in bacterial community.

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Novel Approach to Study the Diversity of Soil Microbial Communities in Qatar

University of the Future: Re-Imagining Research and Higher Education ◽

10.29117/quarfe.2020.0025 ◽

2020 ◽

Author(s):

Jane Oja ◽

Sakeenah Adenan ◽

Abdel-Fattah Talaat ◽

Juha Alatalo

Keyword(s):

Microbial Communities ◽

High Throughput ◽

Mycorrhizal Fungi ◽

High Throughput Sequencing ◽

Soil Microbial Communities ◽

Arbuscular Mycorrhizal ◽

Soil Microbial ◽

Fungal Abundance ◽

Novel Approach ◽

Soil Climate

A broad diversity of microorganisms can be found in soil, where they are essential for nutrient cycling and energy transfer. Recent high-throughput sequencing methods have greatly advanced our knowledge about how soil, climate and vegetation variables structure the composition of microbial communities in many world regions. However, we are lacking information from several regions in the world, e.g. Middle-East. We have collected soil from 19 different habitat types for studying the diversity and composition of soil microbial communities (both fungi and bacteria) in Qatar and determining which edaphic parameters exert the strongest influences on these communities. Preliminary results indicate that in overall bacteria are more abundant in soil than fungi and few sites have notably higher abundance of these microbes. In addition, we have detected some soil patameters, which tend to have reduced the overall fungal abundance and enhanced the presence of arbuscular mycorrhizal fungi and N-fixing bacteria. More detailed information on the diversity and composition of soil microbial communities is expected from the high-throughput sequenced data.

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Effects of earthworms and arbuscular mycorrhizal fungi on improvement of fertility and microbial communities of soils heavily polluted by cadmium

Chemosphere ◽

10.1016/j.chemosphere.2021.131567 ◽

2021 ◽

pp. 131567

Author(s):

Gen Wang ◽

Li Wang ◽

Fang Ma

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Microbial Communities ◽

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal

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Meta-Analysis of Microbial Communities in Hot Springs: Recurrent Taxa and Complex Shaping Factors beyond pH and Temperature

Microorganisms ◽

10.3390/microorganisms8060906 ◽

2020 ◽

Vol 8 (6) ◽

pp. 906 ◽

Cited By ~ 2

Author(s):

Francisco L. Massello ◽

Chia Sing Chan ◽

Kok-Gan Chan ◽

Kian Mau Goh ◽

Edgardo Donati ◽

...

Keyword(s):

Microbial Communities ◽

Metabolic Profile ◽

Hot Springs ◽

Meta Analysis ◽

Extreme Environments ◽

Alpha Diversity ◽

Amplicon Sequencing ◽

Phylogenetic Distance ◽

Microbial Profile ◽

The World

The study of microbial communities from extreme environments is a fascinating topic. With every study, biologists and ecologists reveal interesting facts and questions that dispel the old belief that these are inhospitable environments. In this work, we assess the microbial diversity of three hot springs from Neuquén, Argentina, using high-throughput amplicon sequencing. We predicted a distinct metabolic profile in the acidic and the circumneutral samples, with the first ones being dominated by chemolithotrophs and the second ones by chemoheterotrophs. Then, we collected data of the microbial communities of hot springs around the world in an effort to comprehend the roles of pH and temperature as shaping factors. Interestingly, there was a covariation between both parameters and the phylogenetic distance between communities; however, neither of them could explain much of the microbial profile in an ordination model. Moreover, there was no correlation between alpha diversity and these parameters. Therefore, the microbial communities’ profile seemed to have complex shaping factors beyond pH and temperature. Lastly, we looked for taxa associated with different environmental conditions. Several such taxa were found. For example, Hydrogenobaculum was frequently present in acidic springs, as was the Sulfolobaceae family; on the other hand, Candidatus Hydrothermae phylum was strongly associated with circumneutral conditions. Interestingly, some singularities related to sites featuring certain taxa were also observed.

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Deciphering the Influence of Multiple Anthropogenic Inputs on Taxonomic and Functional Profiles of the Microbial Communities in Yitong River, Northeast China

10.21203/rs.3.rs-729563/v1 ◽

2021 ◽

Author(s):

Ying Zhang ◽

Yang Huo ◽

Zhiruo Zhang ◽

Suiyi Zhu ◽

Wei Fan ◽

...

Keyword(s):

Microbial Communities ◽

Northeast China ◽

Environmental Changes ◽

Quantitative Polymerase Chain Reaction ◽

Amplicon Sequencing ◽

Fecal Indicator ◽

16S Rrna Amplicon Sequencing ◽

Anthropogenic Inputs ◽

Wwtp Effluent ◽

The Impact

Abstract We conducted physicochemical parameters analysis, 16S rRNA amplicon sequencing and real-time quantitative polymerase chain reaction to explore the impact of human inputs on the bacterioplankton communities within a tributary of the largest river flowing through a megacity in northeast China. Agriculture largely accounted for the alteration of diversity and functions of the microbial communities. Furthermore, nutrients were significantly declined at the reservoir outlet, and WWTP effluent discharge caused changes in the river microbial community. NH3-N and NO3--N were the main environmental factors that drive the shift of the bacteria community, and rare taxa played a more important role in the response to environmental changes compared with the abundant ones. The occurrence of the human-specific fecal indicator was mostly derived from agriculture, and its increase in relative abundance was observed in the effluent. Thus, our study provides guidance for ecological assessment and management of rivers by revealing the response pattern of river bacterioplankton to multiple types of anthropogenic stressors.

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Differential responses of arbuscular mycorrhizal fungal communities to long-term fertilization in the wheat rhizosphere and root endosphere

Applied and Environmental Microbiology ◽

10.1128/aem.00349-21 ◽

2021 ◽

Author(s):

Yuying Ma ◽

Huanchao Zhang ◽

Daozhong Wang ◽

Xisheng Guo ◽

Teng Yang ◽

...

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Rhizosphere Soil ◽

Organic Amendments ◽

Alpha Diversity ◽

Arbuscular Mycorrhizal ◽

Mineral Fertilization ◽

Amf Communities ◽

Arbuscular Mycorrhizal Fungal

Arbuscular mycorrhizal fungi (AMF) provide essential nutrients to crops and are critically impacted by fertilization in agricultural ecosystems. Understanding shifts in AMF communities in and around crop roots under different fertilization regimes can provide important lessons for improving agricultural production and sustainability. Here, we compared the responses of AMF communities in the rhizosphere (RS) and root endosphere (ES) of wheat ( Triticum aestivum ) to different fertilization treatments: Non-fertilization (Control), mineral fertilization only (NPK), mineral fertilization plus wheat straw (NPKS), and mineral fertilization plus cow manure (NPKM). We employed high-throughput amplicon sequencing and investigated the diversity, community composition, and network structure of AMF communities to assess their responses to fertilization. Our results elucidated that AMF communities in the RS and ES respond differently to fertilization schemes. Long-term NPK application decreased the RS AMF alpha diversity significantly, whereas additional organic amendments (straw or manure) had no effect. Contrastingly, NPK fertilization increased the ES AMF alpha diversity significantly, while additional organic amendments decreased it significantly. The effect of different fertilization schemes on AMF network complexity in the RS and ES were similar to their effects on alpha diversity. Changes to AMF communities in the RS and ES correlated mainly with the pH and phosphorus level of the rhizosphere soil under long-term inorganic and organic fertilization regimes. We suggest that the AMF community in the roots should be given more consideration when studying the effects of fertilization regimes on AMF in agroecosystems. Importance Arbuscular mycorrhizal fungi are an integral component of rhizospheres, bridging the soil and plant systems and are highly sensitive to fertilization. However, surprisingly little is known about how the response differs between the roots and the surrounding soil. Decreasing arbuscular mycorrhizal fungal diversity under fertilization has been reported, implying a potential reduction in the mutualism between plants and arbuscular mycorrhizal fungi. However, we found opposing responses to long-term fertilization managements of arbuscular mycorrhizal fungi in the wheat roots and rhizosphere soil. These results suggested that changes in the arbuscular mycorrhizal fungal community in soils do not reflect those in the roots, highlighting that the root arbuscular mycorrhizal fungal community is pertinent to understand arbuscular mycorrhizal fungi and their crop hosts’ responses to anthropogenic influences.

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Nitrogen Addition and Arbuscular Mycorrhizal Fungi Beta Diversity: Patterns and Mechanisms

Frontiers in Environmental Science ◽

10.3389/fenvs.2021.701653 ◽

2021 ◽

Vol 9 ◽

Author(s):

Yawen Lu ◽

Xiang Liu ◽

Shurong Zhou

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Beta Diversity ◽

Alpine Meadow ◽

Alpha Diversity ◽

Arbuscular Mycorrhizal ◽

Nitrogen Addition ◽

Tibet Plateau ◽

Community Dissimilarity ◽

Qinghai Tibet Plateau

Global nitrogen eutrophication, which is disrupting the intimate plant–arbuscular mycorrhizal fungi (AMF) symbiosis, can alter the diversity and physiological functions of soil AMF greatly. However, shifts of beta diversity and the intrinsic patterns of AMF community dissimilarities in response to nitrogen addition remain unclear. Based on a 7-year nitrogen addition experiment in a Qinghai–Tibet Plateau alpine meadow, we detected the changes in soil AMF alpha diversity (richness and genus abundance) and the community composition beta diversity by partitioning the two components of Simpson and nestedness dissimilarities along (turnover) and within (variation) nitrogen addition treatments, and fitted with environmental factor dissimilarities. We found that nitrogen addition decreased AMF richness by decreasing the most dominant AMF genus of Glomus but increasing the abundance of the rare genera. The turnover of the AMF community overall beta diversity along the nitrogen addition gradients was induced by the increased nestedness dissimilarity, while the variation within treatments was explained by both increased Simpson and nestedness dissimilarities, which was significantly correlated with soil pH. Our study found both Simpson and nestedness dissimilarities worked on the AMF community dissimilarity after nitrogen addition and the significant variation within the same treatment, which would be important in the future for predicting global AMF or microbial diversity changes in response to nitrogen eutrophication.

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Influence of introduced arbuscular mycorrhizal fungi and phosphorus sources on plant traits, soil properties, and rhizosphere microbial communities in organic legume-flax rotation

Plant and Soil ◽

10.1007/s11104-019-04213-8 ◽

2019 ◽

Vol 443 (1-2) ◽

pp. 87-106 ◽

Cited By ~ 1

Author(s):

Yunliang Li ◽

Yantai Gan ◽

Newton Lupwayi ◽

Chantal Hamel

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Soil Properties ◽

Microbial Communities ◽

Mycorrhizal Fungi ◽

Plant Traits ◽

Arbuscular Mycorrhizal ◽

Phosphorus Sources

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Mycorrhiza-released glomalin-related soil protein fractions contribute to soil total nitrogen in trifoliate orange

Plant Soil and Environment ◽

10.17221/100/2020-pse ◽

2020 ◽

Vol 66 (No. 4) ◽

pp. 183-189 ◽

Cited By ~ 1

Author(s):

Lu-Lu Meng ◽

Jia-Dong He ◽

Ying-Ning Zou ◽

Qiang-Sheng Wu ◽

Kamil Kuča

Keyword(s):

Mycorrhizal Fungi ◽

Soil Nutrient ◽

Arbuscular Mycorrhizal ◽

Total Biomass ◽

N Accumulation ◽

N Content ◽

Total N ◽

Root Box ◽

Area And Volume ◽

Soil Protein

Glomalin released from arbuscular mycorrhizal fungi (AMF) has important roles in soil nutrient cycles, whereas contributing to glomalin-related soil protein (GRSP) fractions to soil nitrogen (N) is unknown. In this study, a two-chambered root-box that was divided into root chamber (root and mycorrhizal fungi hypha) and hypha chamber (free of the root) was used, and three AMF species including Diversispora epigaea, Paraglomus occultum, and Rhizoglomus intraradices were separately inoculated into the root chamber. Plant growth, soil total N, N content of purified GRSP fractions, and its contribution to soil total N, and leaf and root N contents were analysed. After four months, total biomass and root total length, surface area, and volume were improved by all AMF inoculations. AMF inoculations dramatically increased soil total N content in two chambers. The N content of purified easily extractable GRSP (EE-GRSP) and difficultly extractable GRSP (DE-GRSP) was 0.10 ± 0.01 mg/g and 0.16 ± 0.02 mg/g, respectively, accounted for 15.6 ± 1.6% and 18.1 ± 1.8% of soil total N, respectively. AMF inoculations stimulated the N accumulation in EE-GRSP and DE-GRSP, especially in the hypha chamber. It concluded that GRSP, especially DE-GRSP, acts as a soil N pool accounting for 33.8 ± 1.9% of soil total N in orchards.

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DISTRIBUTION OF VESICULAR-ARBUSCULAR MYCORRHIZAL FUNGI IN SOILS POLLUTED WITH INDUSTRIAL AND SEWAGE EFFLUENTS

FLORA AND FAUNA ◽

10.33451/florafauna.v25i1pp69-72 ◽

2019 ◽

Vol 25 (1) ◽

Author(s):

N.K. SRIVASTAVA ◽

JAYRAJ PANDEY ◽

INDU SINGH

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Microbial Communities ◽

Mycorrhizal Fungi ◽

Industrial Effluent ◽

Arbuscular Mycorrhizal ◽

Fungal Species ◽

Vam Fungi ◽

Vesicular Arbuscular Mycorrhizal Fungi ◽

Sewage Effluents ◽

Vesicular Arbuscular

The microbial communities including VAM fungi get affected by the sewage and industrial effluent. About this there is not much information. Soil polluted with sewage effluents supported less VAM population than non-polluted. 44 VAM fungal species were collected and indentified.

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