1
|
Wang J, Yao H, Zhang X. The effect of the 13C abundance of soil microbial DNA on identifying labelled fractions after ultracentrifugation. Appl Microbiol Biotechnol 2024; 108:318. [PMID: 38700733 PMCID: PMC11068677 DOI: 10.1007/s00253-024-13151-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 01/17/2024] [Accepted: 04/16/2024] [Indexed: 05/06/2024]
Abstract
DNA-based stable isotope probing (DNA-SIP) technology has been widely employed to trace microbes assimilating target substrates. However, the fractions with labelled universal genes are sometimes difficult to distinguish when detected by quantitative real-time PCR. In this experiment, three paddy soils (AQ, CZ, and NB) were amended with 0.1% glucose containing 13C at six levels, and DNA was then extracted after a 7-day incubation and subjected to isopycnic gradient centrifugation. The results showed that the amount of labelled DNA was notably related to the 13C-glucose percentage, while the separation spans of 18S rRNA and 16S rRNA genes between labelled and unlabelled treatments became notably clearer when the δ13C values of the total DNA were 90.9, 61.6, and 38.9‰ and 256.2, 104.5 and 126.1‰ in the AQ, CZ, and NB soils, respectively. Moreover, fractionated DNA was also labelled by determining the δ13C values while adding only 5 atom% 13C-glucose to the soil. The results suggest that the optimal labelling fractions were not always those fractions with the maximal gene abundance, and detecting the δ13C values of the total and fractionated DNA was beneficial in estimating the results of DNA-SIP. KEY POINTS: • Appropriate 13C-DNA amount was needed for DNA-SIP. • Detecting the 13C ratio of fractionated DNA directly was an assistant method for identifying the labelled fractions. • Fractions with the maximal 18S or 16S rRNA gene abundance always were not labelled.
Collapse
Affiliation(s)
- Juan Wang
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China
- Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control, CAS Haixi Industrial Technology Innovation Center in Beilun, Ningbo, China
| | - Huaiying Yao
- Research Center for Environmental Ecology and Engineering, School of Environmental Ecology and Biological Engineering, Wuhan Institute of Technology, Wuhan, China.
| | - Xian Zhang
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China
| |
Collapse
|
2
|
Lu M, Huang L, Wang Q, Cao X, Lin Q, He Z, Feng Y, Yang X. Soil properties drive the bacterial community to cadmium contamination in the rhizosphere of two contrasting wheat (Triticum aestivum L.) genotypes. J Environ Sci (China) 2023; 128:117-128. [PMID: 36801027 DOI: 10.1016/j.jes.2022.07.028] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 07/17/2022] [Accepted: 07/17/2022] [Indexed: 06/18/2023]
Abstract
Cadmium (Cd) bioavailability in the rhizosphere makes an important difference in grain Cd accumulation in wheat. Here, pot experiments combined with 16S rRNA gene sequencing were conducted to compare the Cd bioavailability and bacterial community in the rhizosphere of two wheat (Triticum aestivum L.) genotypes, a low-Cd-accumulating genotype in grains (LT) and a high-Cd-accumulating genotype in grains (HT), grown on four different soils with Cd contamination. Results showed that there was non-significant difference in total Cd concentration among four soils. However, except for black soil, DTPA-Cd concentrations in HT rhizospheres were higher than those of LT in fluvisol, paddy soil and purple soil. Results of 16S rRNA gene sequencing showed that soil type (52.7%) was the strongest determinant of root-associated community, while there were still some differences in rhizosphere bacterial community composition between two wheat genotypes. Taxa specifically colonized in HT rhizosphere (Acidobacteria, Gemmatimonadetes, Bacteroidetes and Deltaproteobacteria) could participate in metal activation, whereas LT rhizosphere was highly enriched by plant growth-promoting taxa. In addition, PICRUSt2 analysis also predicted high relative abundances of imputed functional profiles related to membrane transport and amino acid metabolism in HT rhizosphere. These results revealed that the rhizosphere bacterial community may be an important factor regulating Cd uptake and accumulation in wheat and indicated that the high Cd-accumulating cultivar might improve Cd bioavailability in the rhizosphere by recruiting taxa related to Cd activation, thus promoting Cd uptake and accumulation.
Collapse
Affiliation(s)
- Min Lu
- Key Laboratory of Environmental Remediation and Ecosystem Health, Ministry of Education (MOE), College of Environmental and Resources Sciences, Zhejiang University, Hangzhou 310058, China; Tea Research Institute, Shandong Academy of Agricultural Sciences, Jinan 250100, China
| | - Lukuan Huang
- Key Laboratory of Environmental Remediation and Ecosystem Health, Ministry of Education (MOE), College of Environmental and Resources Sciences, Zhejiang University, Hangzhou 310058, China
| | - Qiong Wang
- College of Ecology, Taiyuan University of Technology, Taiyuan 030024, China
| | - Xuerui Cao
- Zhejiang Institute of Landscape Plants and Flowers, Hangzhou 311251, China
| | - Qiang Lin
- Key Laboratory of Environmental Remediation and Ecosystem Health, Ministry of Education (MOE), College of Environmental and Resources Sciences, Zhejiang University, Hangzhou 310058, China
| | - Zhenli He
- University of Florida, Institute of Food and Agricultural Sciences, Indian River Research and Education Center, Fort Pierce, FL 34945, USA
| | - Ying Feng
- Key Laboratory of Environmental Remediation and Ecosystem Health, Ministry of Education (MOE), College of Environmental and Resources Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xiaoe Yang
- Key Laboratory of Environmental Remediation and Ecosystem Health, Ministry of Education (MOE), College of Environmental and Resources Sciences, Zhejiang University, Hangzhou 310058, China.
| |
Collapse
|
3
|
Poupin MJ, Ledger T, Roselló-Móra R, González B. The Arabidopsis holobiont: a (re)source of insights to understand the amazing world of plant-microbe interactions. ENVIRONMENTAL MICROBIOME 2023; 18:9. [PMID: 36803555 PMCID: PMC9938593 DOI: 10.1186/s40793-023-00466-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Accepted: 01/19/2023] [Indexed: 06/18/2023]
Abstract
As holobiont, a plant is intrinsically connected to its microbiomes. However, some characteristics of these microbiomes, such as their taxonomic composition, biological and evolutionary role, and especially the drivers that shape them, are not entirely elucidated. Reports on the microbiota of Arabidopsis thaliana first appeared more than ten years ago. However, there is still a lack of a comprehensive understanding of the vast amount of information that has been generated using this holobiont. The main goal of this review was to perform an in-depth, exhaustive, and systematic analysis of the literature regarding the Arabidopsis-microbiome interaction. A core microbiota was identified as composed of a few bacterial and non-bacterial taxa. The soil (and, to a lesser degree, air) were detected as primary microorganism sources. From the plant perspective, the species, ecotype, circadian cycle, developmental stage, environmental responses, and the exudation of metabolites were crucial factors shaping the plant-microbe interaction. From the microbial perspective, the microbe-microbe interactions, the type of microorganisms belonging to the microbiota (i.e., beneficial or detrimental), and the microbial metabolic responses were also key drivers. The underlying mechanisms are just beginning to be unveiled, but relevant future research needs were identified. Thus, this review provides valuable information and novel analyses that will shed light to deepen our understanding of this plant holobiont and its interaction with the environment.
Collapse
Affiliation(s)
- M J Poupin
- Laboratorio de Bioingeniería, Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, 7941169, Santiago, Chile
- Center of Applied Ecology and Sustainability (CAPES), Santiago, Chile
- Millennium Nucleus for the Development of Super Adaptable Plants (MN-SAP), Santiago, Chile
| | - T Ledger
- Laboratorio de Bioingeniería, Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, 7941169, Santiago, Chile
- Center of Applied Ecology and Sustainability (CAPES), Santiago, Chile
- Millennium Nucleus for the Development of Super Adaptable Plants (MN-SAP), Santiago, Chile
| | - R Roselló-Móra
- Marine Microbiology Group, Department of Animal and Microbial Biodiversity, Mediterranean Institute for Advanced Studies (IMEDEA UIB-CSIC), Illes Balears, Majorca, Spain
| | - B González
- Laboratorio de Bioingeniería, Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, 7941169, Santiago, Chile.
- Center of Applied Ecology and Sustainability (CAPES), Santiago, Chile.
- Millennium Nucleus for the Development of Super Adaptable Plants (MN-SAP), Santiago, Chile.
| |
Collapse
|
4
|
Xu Y, Ding H, Zhang G, Li Z, Guo Q, Feng H, Qin F, Dai L, Zhang Z. Green manure increases peanut production by shaping the rhizosphere bacterial community and regulating soil metabolites under continuous peanut production systems. BMC PLANT BIOLOGY 2023; 23:69. [PMID: 36726076 PMCID: PMC9890850 DOI: 10.1186/s12870-023-04079-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 01/20/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND Green manure (GM) is a crop commonly grown during fallow periods, which has been applied in agriculture as a strategy to regulate nutrient cycling, improve organic matter, and enhance soil microbial biodiversity, but to date, few studies have examined the effects of GM treatments on rhizosphere soil bacterial community and soil metabolites from continuous cropping peanut field. RESULTS In this study, we found that the abundances of several functionally significant bacterial groups containing Actinobacteria, Acidobacteria, and genus Sphingomonas, which are associated with nitrogen cycling, were dramatically increased in GM-applied soils. Consistent with the bacterial community results, metabolomics analysis revealed a strong perturbation of nitrogen- or carbon-related metabolisms in GM-applied soils. The substantially up-regulated beneficial metabolites including sucrose, adenine, lysophosphatidylcholine (LPC), malic acid, and betaines in GM-applied soils may contribute to overcome continuous cropping obstacle. In contrast to peanut continuous cropping, planting winter wheat and oilseed rape in winter fallow period under continuous spring peanut production systems evidently improved the soil quality, concomitantly with raised peanut pod yield by 32.93% and 25.20%, in the 2020 season, respectively. CONCLUSIONS GMs application is an effective strategy to overcome continuous cropping obstacle under continuous peanut production systems by improving nutrient cycling, soil metabolites, and rhizobacterial properties.
Collapse
Affiliation(s)
- Yang Xu
- Shandong Peanut Research Institute, Shandong Academy of Agricultural Sciences, Qingdao, Shandong, China
| | - Hong Ding
- Shandong Peanut Research Institute, Shandong Academy of Agricultural Sciences, Qingdao, Shandong, China
| | - Guanchu Zhang
- Shandong Peanut Research Institute, Shandong Academy of Agricultural Sciences, Qingdao, Shandong, China
| | - Zelun Li
- Shandong Peanut Research Institute, Shandong Academy of Agricultural Sciences, Qingdao, Shandong, China
| | - Qing Guo
- Shandong Peanut Research Institute, Shandong Academy of Agricultural Sciences, Qingdao, Shandong, China
| | - Hao Feng
- Shandong Peanut Research Institute, Shandong Academy of Agricultural Sciences, Qingdao, Shandong, China
| | - Feifei Qin
- Shandong Peanut Research Institute, Shandong Academy of Agricultural Sciences, Qingdao, Shandong, China
| | - Liangxiang Dai
- Shandong Peanut Research Institute, Shandong Academy of Agricultural Sciences, Qingdao, Shandong, China.
| | - Zhimeng Zhang
- Shandong Peanut Research Institute, Shandong Academy of Agricultural Sciences, Qingdao, Shandong, China.
| |
Collapse
|
5
|
Jameson E, Taubert M, Angel R, Coyotzi S, Chen Y, Eyice Ö, Schäfer H, Murrell JC, Neufeld JD, Dumont MG. DNA-, RNA-, and Protein-Based Stable-Isotope Probing for High-Throughput Biomarker Analysis of Active Microorganisms. Methods Mol Biol 2023; 2555:261-282. [PMID: 36306091 DOI: 10.1007/978-1-0716-2795-2_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Stable-isotope probing (SIP) enables researchers to target active populations within complex microbial communities, which is achieved by providing growth substrates enriched in heavy isotopes, usually in the form of 13C, 18O, or 15N. After growth on the substrate and subsequent extraction of microbial biomarkers, typically nucleic acids or proteins, the SIP technique is used for the recovery and analysis of isotope-labelled biomarkers from active microbial populations. In the years following the initial development of DNA- and RNA-based SIP, it was common practice to characterize labelled populations by targeted gene analysis. Such approaches usually involved fingerprint-based analyses or sequencing clone libraries containing 16S rRNA genes or functional marker gene amplicons. Although molecular fingerprinting remains a valuable approach for rapid confirmation of isotope labelling, recent advances in sequencing technology mean that it is possible to obtain affordable and comprehensive amplicon profiles, or even metagenomes and metatranscriptomes from SIP experiments. Not only can the abundance of microbial groups be inferred from metagenomes, but researchers can bin, assemble, and explore individual genomes to build hypotheses about the metabolic capabilities of labelled microorganisms. Analysis of labelled mRNA is a more recent advance that can provide independent metatranscriptome-based analysis of active microorganisms. The power of metatranscriptomics is that mRNA abundance often correlates closely with the corresponding activity of encoded enzymes, thus providing insight into microbial metabolism at the time of sampling. Together, these advances have improved the sensitivity of SIP methods and allowed using labelled substrates at environmentally relevant concentrations. Particularly as methods improve and costs continue to drop, we expect that the integration of SIP with multiple omics-based methods will become prevalent components of microbial ecology studies, leading to further breakthroughs in our understanding of novel microbial populations and elucidation of the metabolic function of complex microbial communities. In this chapter, we provide protocols for obtaining labelled DNA, RNA, and proteins that can be used for downstream omics-based analyses.
Collapse
Affiliation(s)
- Eleanor Jameson
- School of Life Sciences, University of Warwick, Coventry, UK
| | - Martin Taubert
- Aquatic Geochemistry, Institute of Biodiversity, Friedrich Schiller University, Jena, Germany
| | - Roey Angel
- Soil & Water Research Infrastructure and Institute of Soil Biology, Biology Centre CAS, České Budějovice, Czechia
| | - Sara Coyotzi
- Department of Biology, University of Waterloo, Waterloo, Canada
| | - Yin Chen
- School of Life Sciences, University of Warwick, Coventry, UK
| | - Özge Eyice
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK
| | - Hendrik Schäfer
- School of Life Sciences, University of Warwick, Coventry, UK
| | - J Colin Murrell
- School of Environmental Sciences, University of East Anglia, Norwich, UK
| | - Josh D Neufeld
- Department of Biology, University of Waterloo, Waterloo, Canada
| | - Marc G Dumont
- School of Biological Sciences, University of Southampton, Southampton, UK.
| |
Collapse
|
6
|
Ye L, Wang X, Wei S, Zhu Q, He S, Zhou L. Dynamic analysis of the microbial communities and metabolome of healthy banana rhizosphere soil during one growth cycle. PeerJ 2022; 10:e14404. [PMID: 36420134 PMCID: PMC9677880 DOI: 10.7717/peerj.14404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 10/26/2022] [Indexed: 11/21/2022] Open
Abstract
Background The banana-growing rhizosphere soil ecosystem is very complex and consists of an entangled network of interactions between banana plants, microbes and soil, so identifying key components in banana production is difficult. Most of the previous studies on these interactions ignore the role of the banana plant. At present, there is no research on the the micro-ecological environment of the banana planting growth cycle. Methods Based on high-throughput sequencing technology and metabolomics technology, this study analyzed the rhizosphere soil microbial community and metabolic dynamics of healthy banana plants during one growth cycle. Results Assessing the microbial community composition of healthy banana rhizosphere soil, we found that the bacteria with the highest levels were Proteobacteria, Chloroflexi, and Acidobacteria, and the dominant fungi were Ascomycota, Basidiomycota, and Mortierellomycota. The metabolite profile of healthy banana rhizosphere soil showed that sugars, lipids and organic acids were the most abundant, accounting for about 50% of the total metabolites. The correlation network between fungi and metabolites was more complex than that of bacteria and metabolites. In a soil environment with acidic pH, bacterial genera showed a significant negative correlation with pH value, while fungal genera showed no significant negative correlation with pH value. The network interactions between bacteria, between fungi, and between bacteria and fungi were all positively correlated. Conclusions Healthy banana rhizosphere soil not only has a stable micro-ecology, but also has stable metabolic characteristics. The microorganisms in healthy banana rhizosphere soil have mutually beneficial rather than competitive relationships.
Collapse
Affiliation(s)
- Liujian Ye
- Guangxi Biological Science and Technology Research Center, Guangxi Academy of Sciences, Nanning, China,State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Nanning, China,National Engineering Research Center for Non-Food Biorefinery, Guangxi Academy of Sciences, Nanning, China
| | - Xiaohu Wang
- Guangxi Biological Science and Technology Research Center, Guangxi Academy of Sciences, Nanning, China,State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Nanning, China,National Engineering Research Center for Non-Food Biorefinery, Guangxi Academy of Sciences, Nanning, China
| | - Shengbo Wei
- Guangxi Biological Science and Technology Research Center, Guangxi Academy of Sciences, Nanning, China,State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Nanning, China,National Engineering Research Center for Non-Food Biorefinery, Guangxi Academy of Sciences, Nanning, China
| | - Qixia Zhu
- Guangxi Biological Science and Technology Research Center, Guangxi Academy of Sciences, Nanning, China,State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Nanning, China,National Engineering Research Center for Non-Food Biorefinery, Guangxi Academy of Sciences, Nanning, China
| | - Shuang He
- Guangxi Biological Science and Technology Research Center, Guangxi Academy of Sciences, Nanning, China,State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Nanning, China,National Engineering Research Center for Non-Food Biorefinery, Guangxi Academy of Sciences, Nanning, China
| | - Liqin Zhou
- Guangxi Biological Science and Technology Research Center, Guangxi Academy of Sciences, Nanning, China,State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Nanning, China,National Engineering Research Center for Non-Food Biorefinery, Guangxi Academy of Sciences, Nanning, China
| |
Collapse
|
7
|
Aslam MM, Karanja JK, Dodd IC, Waseem M, Weifeng X. Rhizosheath: An adaptive root trait to improve plant tolerance to phosphorus and water deficits? PLANT, CELL & ENVIRONMENT 2022; 45:2861-2874. [PMID: 35822342 PMCID: PMC9544408 DOI: 10.1111/pce.14395] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 07/07/2022] [Accepted: 07/11/2022] [Indexed: 06/09/2023]
Abstract
Drought and nutrient limitations adversely affect crop yields, with below-ground traits enhancing crop production in these resource-poor environments. This review explores the interacting biological, chemical and physical factors that determine rhizosheath (soil adhering to the root system) development, and its influence on plant water uptake and phosphorus acquisition in dry soils. Identification of quantitative trait loci for rhizosheath development indicate it is genetically determined, but the microbial community also directly (polysaccharide exudation) and indirectly (altered root hair development) affect its extent. Plants with longer and denser root hairs had greater rhizosheath development and increased P uptake efficiency. Moreover, enhanced rhizosheath formation maintains contact at the root-soil interface thereby assisting water uptake from drying soil, consequently improving plant survival in droughted environments. Nevertheless, it can be difficult to determine if rhizosheath development is a cause or consequence of improved plant adaptation to dry and nutrient-depleted soils. Does rhizosheath development directly enhance plant water and phosphorus use, or do other tolerance mechanisms allow plants to invest more resources in rhizosheath development? Much more work is required on the interacting genetic, physical, biochemical and microbial mechanisms that determine rhizosheath development, to demonstrate that selection for rhizosheath development is a viable crop improvement strategy.
Collapse
Affiliation(s)
- Mehtab Muhammad Aslam
- Center for Plant Water‐Use and Nutrition Regulation, College of Resource and EnvironmentFujian Agriculture and Forestry UniversityFuzhouFujianChina
- College of AgricultureYangzhou UniversityYangzhouJiangsuChina
- State Key Laboratory of Agrobiotechnology, School of Life SciencesThe Chinese University of Hong KongShatinHong Kong
| | - Joseph K. Karanja
- Center for Plant Water‐Use and Nutrition Regulation, College of Resource and EnvironmentFujian Agriculture and Forestry UniversityFuzhouFujianChina
| | - Ian C. Dodd
- The Lancaster Environment CentreLancaster UniversityLancasterUK
| | | | - Xu Weifeng
- Center for Plant Water‐Use and Nutrition Regulation, College of Resource and EnvironmentFujian Agriculture and Forestry UniversityFuzhouFujianChina
- College of AgricultureYangzhou UniversityYangzhouJiangsuChina
| |
Collapse
|
8
|
Luo J, Gu S, Guo X, Liu Y, Tao Q, Zhao HP, Liang Y, Banerjee S, Li T. Core Microbiota in the Rhizosphere of Heavy Metal Accumulators and Its Contribution to Plant Performance. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:12975-12987. [PMID: 36067360 DOI: 10.1021/acs.est.1c08832] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Persistent microbial symbioses can confer greater fitness to their host under unfavorable conditions, but manipulating such beneficial interactions necessitates a mechanistic understanding of the consistently important microbiomes for the plant. Here, we examined the phylogenetic profiles and plant-beneficial traits of the core microbiota that consistently inhabits the rhizosphere of four divergent Cd hyperaccumulators and an accumulator. We evidenced the existence of a conserved core rhizosphere microbiota in each plant distinct from that in the non-hyperaccumulating plant. Members of Burkholderiaceae and Sphingomonas were the shared cores across hyperaccumulators and accumulators. Several keystone taxa in the rhizosphere networks were part of the core microbiota, the abundance of which was an important predictor of plant Cd accumulation. Furthermore, an inoculation experiment with synthetic communities comprising isolates belonging to the shared cores indicated that core microorganisms could facilitate plant growth and metal tolerance. Using RNA-based stable isotope probing, we discovered that abundant core taxa overlapped with active rhizobacteria utilizing root exudates, implying that the core rhizosphere microbiota assimilating plant-derived carbon may provide benefits to plant growth and host phenotype such as Cd accumulation. Our study suggests common principles underpinning hyperaccumulator-microbiome interactions, where plants consistently interact with a core set of microbes contributing to host fitness and plant performance. These findings lay the foundation for harnessing the persistent root microbiomes to accelerate the restoration of metal-disturbed soils.
Collapse
Affiliation(s)
- Jipeng Luo
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Shaohua Gu
- Center for Quantitative Biology and Peking-Tsinghua Center for Life Sciences, Peking University, 100091 Beijing, China
| | - Xinyu Guo
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yuankun Liu
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Qi Tao
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - He-Ping Zhao
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yongchao Liang
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Samiran Banerjee
- Department of Microbiological Sciences, North Dakota State University, Fargo, North Dakota 58108-6050, United States
| | - Tingqiang Li
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| |
Collapse
|
9
|
Laveilhé A, Fochesato S, Lalaouna D, Heulin T, Achouak W. Phytobeneficial traits of rhizobacteria under the control of multiple molecular dialogues. Microb Biotechnol 2022; 15:2083-2096. [PMID: 35502577 PMCID: PMC9249325 DOI: 10.1111/1751-7915.14023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 02/14/2022] [Accepted: 02/14/2022] [Indexed: 11/29/2022] Open
Abstract
Pseudomonads play crucial roles in plant growth promotion and control of plant diseases. However, under natural conditions, other microorganisms competing for the same nutrient resources in the rhizosphere may exert negative control over their phytobeneficial characteristics. We assessed the expression of phytobeneficial genes involved in biocontrol, biostimulation and iron regulation such as, phlD, hcnA, acdS, and iron‐small regulatory RNAs prrF1 and prrF2 in Pseudomonas brassicacearum co‐cultivated with three phytopathogenic fungi, and two rhizobacteria in the presence or absence of Brassica napus, and in relation to iron availability. We found that the antifungal activity of P. brassicacearum depends mostly on the production of DAPG and not on HCN whose production is suppressed by fungi. We have also shown that the two‐competing bacterial strains modulate the plant growth promotion activity of P. brassicacearum by modifying the expression of phlD, hcnA and acdS according to iron availability. Overall, it allows us to better understand the complexity of the multiple molecular dialogues that take place underground between microorganisms and between plants and its rhizosphere microbiota and to show that synergy in favour of phytobeneficial gene expression may exist between different bacterial species. We assessed the expression of phytobeneficial genes, phlD, hcnA and acdS, and iron‐small regulatory RNAs prrF1 and prrF2 in Pseudomonas brassicacearum co‐cultivated with three phytopathogenic fungi, and two rhizobacteria in the presence or absence of Brassica napus, and in relation to iron availability. Our study illustrates that interkingdom and interspecies interactions in addition to external factors may affect the success of introduced beneficial microorganisms by modulating the expression of phytobeneficial genes.
Collapse
Affiliation(s)
- Arnaud Laveilhé
- Lab Microbial Ecology of the Rhizosphere (LEMiRE), CEA, CNRS, BIAM, Aix Marseille Univ, Saint-Paul-Lez-Durance, F-13108, France
| | - Sylvain Fochesato
- Lab Microbial Ecology of the Rhizosphere (LEMiRE), CEA, CNRS, BIAM, Aix Marseille Univ, Saint-Paul-Lez-Durance, F-13108, France
| | - David Lalaouna
- ARN UPR 9002, Université de Strasbourg, CNRS, Strasbourg, F-67000, France
| | - Thierry Heulin
- Lab Microbial Ecology of the Rhizosphere (LEMiRE), CEA, CNRS, BIAM, Aix Marseille Univ, Saint-Paul-Lez-Durance, F-13108, France
| | - Wafa Achouak
- Lab Microbial Ecology of the Rhizosphere (LEMiRE), CEA, CNRS, BIAM, Aix Marseille Univ, Saint-Paul-Lez-Durance, F-13108, France
| |
Collapse
|
10
|
Franzino T, Boubakri H, Cernava T, Abrouk D, Achouak W, Reverchon S, Nasser W, Haichar FEZ. Implications of carbon catabolite repression for plant-microbe interactions. PLANT COMMUNICATIONS 2022; 3:100272. [PMID: 35529946 PMCID: PMC9073323 DOI: 10.1016/j.xplc.2021.100272] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 11/17/2021] [Accepted: 12/27/2021] [Indexed: 06/14/2023]
Abstract
Carbon catabolite repression (CCR) plays a key role in many physiological and adaptive responses in a broad range of microorganisms that are commonly associated with eukaryotic hosts. When a mixture of different carbon sources is available, CCR, a global regulatory mechanism, inhibits the expression and activity of cellular processes associated with utilization of secondary carbon sources in the presence of the preferred carbon source. CCR is known to be executed by completely different mechanisms in different bacteria, yeast, and fungi. In addition to regulating catabolic genes, CCR also appears to play a key role in the expression of genes involved in plant-microbe interactions. Here, we present a detailed overview of CCR mechanisms in various bacteria. We highlight the role of CCR in beneficial as well as deleterious plant-microbe interactions based on the available literature. In addition, we explore the global distribution of known regulatory mechanisms within bacterial genomes retrieved from public repositories and within metatranscriptomes obtained from different plant rhizospheres. By integrating the available literature and performing targeted meta-analyses, we argue that CCR-regulated substrate use preferences of microorganisms should be considered an important trait involved in prevailing plant-microbe interactions.
Collapse
Affiliation(s)
- Theophile Franzino
- INSA-Lyon, Université Claude Bernard Lyon 1, CNRS, UMR5240, Microbiologie, Adaptation, Pathogénie, Université Lyon, 10 rue Raphaël Dubois, 69622 Villeurbanne, France
| | - Hasna Boubakri
- Université Lyon, Université Claude Bernard Lyon 1, CNRS, INRAE, VetAgro Sup, UMR Écologie Microbienne, 69622 Villeurbanne, France
| | - Tomislav Cernava
- Institute of Environmental Biotechnology, Graz University of Technology, Petersgasse 12/I, Graz 8010, Austria
| | - Danis Abrouk
- Université Lyon, Université Claude Bernard Lyon 1, CNRS, INRAE, VetAgro Sup, UMR Écologie Microbienne, 69622 Villeurbanne, France
| | - Wafa Achouak
- Aix Marseille Université, CEA, CNRS, BIAM, Lab Microbial Ecology of the Rhizosphere (LEMiRE), 13108 Saint-Paul-Lez-Durance, France
| | - Sylvie Reverchon
- INSA-Lyon, Université Claude Bernard Lyon 1, CNRS, UMR5240, Microbiologie, Adaptation, Pathogénie, Université Lyon, 10 rue Raphaël Dubois, 69622 Villeurbanne, France
| | - William Nasser
- INSA-Lyon, Université Claude Bernard Lyon 1, CNRS, UMR5240, Microbiologie, Adaptation, Pathogénie, Université Lyon, 10 rue Raphaël Dubois, 69622 Villeurbanne, France
| | - Feth el Zahar Haichar
- INSA-Lyon, Université Claude Bernard Lyon 1, CNRS, UMR5240, Microbiologie, Adaptation, Pathogénie, Université Lyon, 10 rue Raphaël Dubois, 69622 Villeurbanne, France
| |
Collapse
|
11
|
Stable-Isotope-Informed, Genome-Resolved Metagenomics Uncovers Potential Cross-Kingdom Interactions in Rhizosphere Soil. mSphere 2021; 6:e0008521. [PMID: 34468166 PMCID: PMC8550312 DOI: 10.1128/msphere.00085-21] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The functioning, health, and productivity of soil are intimately tied to a complex network of interactions, particularly in plant root-associated rhizosphere soil. We conducted a stable-isotope-informed, genome-resolved metagenomic study to trace carbon from Avena fatua grown in a 13CO2 atmosphere into soil. We collected paired rhizosphere and nonrhizosphere soil at 6 and 9 weeks of plant growth and extracted DNA that was then separated by density using ultracentrifugation. Thirty-two fractions from each of five samples were grouped by density, sequenced, assembled, and binned to generate 55 unique bacterial genomes that were ≥70% complete. We also identified complete 18S rRNA sequences of several 13C-enriched microeukaryotic bacterivores and fungi. We generated 10 circularized bacteriophage (phage) genomes, some of which were the most labeled entities in the rhizosphere, suggesting that phage may be important agents of turnover of plant-derived C in soil. CRISPR locus targeting connected one of these phage to a Burkholderiales host predicted to be a plant pathogen. Another highly labeled phage is predicted to replicate in a Catenulispora sp., a possible plant growth-promoting bacterium. We searched the genome bins for traits known to be used in interactions involving bacteria, microeukaryotes, and plant roots and found DNA from heavily 13C-labeled bacterial genes thought to be involved in modulating plant signaling hormones, plant pathogenicity, and defense against microeukaryote grazing. Stable-isotope-informed, genome-resolved metagenomics indicated that phage can be important agents of turnover of plant-derived carbon in soil. IMPORTANCE Plants grow in intimate association with soil microbial communities; these microbes can facilitate the availability of essential resources to plants. Thus, plant productivity commonly depends on interactions with rhizosphere bacteria, viruses, and eukaryotes. Our work is significant because we identified the organisms that took up plant-derived organic C in rhizosphere soil and determined that many of the active bacteria are plant pathogens or can impact plant growth via hormone modulation. Further, by showing that bacteriophage accumulate CO2-derived carbon, we demonstrated their vital roles in redistribution of plant-derived C into the soil environment through bacterial cell lysis. The use of stable-isotope probing (SIP) to identify consumption (or lack thereof) of root-derived C by key microbial community members within highly complex microbial communities opens the way for assessing manipulations of bacteria and phage with potentially beneficial and detrimental traits, ultimately providing a path to improved plant health and soil carbon storage.
Collapse
|
12
|
Huang L, Wang X, Chi Y, Huang L, Li WC, Ye Z. Rhizosphere bacterial community composition affects cadmium and arsenic accumulation in rice (Oryza sativa L.). ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 222:112474. [PMID: 34214770 DOI: 10.1016/j.ecoenv.2021.112474] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 06/25/2021] [Accepted: 06/27/2021] [Indexed: 06/13/2023]
Abstract
Cadmium (Cd) and arsenic (As) contamination in paddy soils poses serious health risks to humans. The accumulation of Cd and As in rice (Oryza sativa L.) depends on their bioavailability, which is affected by soil physicochemical properties and soil microbial activities. However, little is known about the intricate interplay between rice plants and their rhizosphere microbes during the uptake of Cd and As. In this study, different bacterial communities were established by sterilizing paddy soils with γ-radiation. A pot experiment using two paddy soils with different levels of contamination was conducted to explore how the bacterial community composition affects Cd and As accumulation in rice plants. The results showed that the sterilization treatment substantially changed the bacterial composition in the rhizosphere, and significantly increased the grain yield (by 33.5-38.3%). The sterilization treatment resulted in significantly decreased concentrations of Cd (by 18.2-38.7%) and As (by 20.3-36.7%) in the grain, straw, and root of rice plants. The accumulation of Cd and As in rice plants was negatively correlated with the relative abundance of sulfate-reducing bacteria and iron-oxidizing bacteria in the rhizosphere. Other specific taxa associated with the accumulation of Cd and As in rice plants were also identified. Our results suggest that regulating the composition of the rhizosphere bacterial community could simultaneously reduce Cd and As accumulation in rice grain and increase the grain yield. These results would be useful for developing strategies to cultivate safe rice crops in areas contaminated with Cd and As.
Collapse
Affiliation(s)
- Lu Huang
- School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China.
| | - Xun Wang
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China.
| | - Yihan Chi
- School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China.
| | - Linan Huang
- School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China.
| | - Wai Chin Li
- Department of Science and Environmental Studies, The Education University of Hong Kong, Hong Kong, China.
| | - Zhihong Ye
- School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China.
| |
Collapse
|
13
|
Worsley SF, Macey MC, Prudence SMM, Wilkinson B, Murrell JC, Hutchings MI. Investigating the Role of Root Exudates in Recruiting Streptomyces Bacteria to the Arabidopsis thaliana Microbiome. Front Mol Biosci 2021; 8:686110. [PMID: 34222338 PMCID: PMC8241931 DOI: 10.3389/fmolb.2021.686110] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 05/27/2021] [Indexed: 02/01/2023] Open
Abstract
Streptomyces species are saprophytic soil bacteria that produce a diverse array of specialized metabolites, including half of all known antibiotics. They are also rhizobacteria and plant endophytes that can promote plant growth and protect against disease. Several studies have shown that streptomycetes are enriched in the rhizosphere and endosphere of the model plant Arabidopsis thaliana. Here, we set out to test the hypothesis that they are attracted to plant roots by root exudates, and specifically by the plant phytohormone salicylate, which they might use as a nutrient source. We confirmed a previously published report that salicylate over-producing cpr5 plants are colonized more readily by streptomycetes but found that salicylate-deficient sid2-2 and pad4 plants had the same levels of root colonization by Streptomyces bacteria as the wild-type plants. We then tested eight genome sequenced Streptomyces endophyte strains in vitro and found that none were attracted to or could grow on salicylate as a sole carbon source. We next used 13CO2 DNA stable isotope probing to test whether Streptomyces species can feed off a wider range of plant metabolites but found that Streptomyces bacteria were outcompeted by faster growing proteobacteria and did not incorporate photosynthetically fixed carbon into their DNA. We conclude that, given their saprotrophic nature and under conditions of high competition, streptomycetes most likely feed on more complex organic material shed by growing plant roots. Understanding the factors that impact the competitiveness of strains in the plant root microbiome could have consequences for the effective application of biocontrol strains.
Collapse
Affiliation(s)
- Sarah F Worsley
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, United Kingdom
| | - Michael C Macey
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, United Kingdom
| | - Samuel M M Prudence
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, United Kingdom.,Department of Molecular Microbiology, John Innes Centre, Norwich Research Park, Norwich, United Kingdom
| | - Barrie Wilkinson
- Department of Molecular Microbiology, John Innes Centre, Norwich Research Park, Norwich, United Kingdom
| | - J Colin Murrell
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, United Kingdom
| | - Matthew I Hutchings
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, United Kingdom.,Department of Molecular Microbiology, John Innes Centre, Norwich Research Park, Norwich, United Kingdom
| |
Collapse
|
14
|
Pande A, Mun BG, Lee DS, Khan M, Lee GM, Hussain A, Yun BW. NO Network for Plant-Microbe Communication Underground: A Review. FRONTIERS IN PLANT SCIENCE 2021; 12:658679. [PMID: 33815456 PMCID: PMC8010196 DOI: 10.3389/fpls.2021.658679] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 02/24/2021] [Indexed: 05/30/2023]
Abstract
Mechanisms governing plant-microbe interaction in the rhizosphere attracted a lot of investigative attention in the last decade. The rhizosphere is not simply a source of nutrients and support for the plants; it is rather an ecosystem teeming with diverse flora and fauna including different groups of microbes that are useful as well as harmful for the plants. Plant-microbe interaction occurs via a highly complex communication network that involves sophisticated machinery for the recognition of friend and foe at both sides. On the other hand, nitric oxide (NO) is a key, signaling molecule involved in plant development and defense. Studies on legume-rhizobia symbiosis suggest the involvement of NO during recognition, root hair curling, development of infection threads, nodule development, and nodule senescence. A similar role of NO is also suggested in the case of plant interaction with the mycorrhizal fungi. Another, insight into the plant-microbe interaction in the rhizosphere comes from the recognition of pathogen-associated molecular patterns (PAMPs)/microbe-associated molecular patterns (MAMPs) by the host plant and thereby NO-mediated activation of the defense signaling cascade. Thus, NO plays a major role in mediating the communication between plants and microbes in the rhizosphere. Interestingly, reports suggesting the role of silicon in increasing the number of nodules, enhancing nitrogen fixation, and also the combined effect of silicon and NO may indicate a possibility of their interaction in mediating microbial communication underground. However, the exact role of NO in mediating plant-microbe interaction remains elusive. Therefore, understanding the role of NO in underground plant physiology is very important, especially in relation to the plant's interaction with the rhizospheric microbiome. This will help devise new strategies for protection against phytopathogens and enhancing plant productivity by promoting symbiotic interaction. This review focuses on the role of NO in plant-microbe communication underground.
Collapse
Affiliation(s)
- Anjali Pande
- Laboratory of Plant Molecular Pathology and Functional Genomics, Department of Plant Biosciences, School of Applied Biosciences, College of Agriculture and Life Science, Kyungpook National University, Daegu, South Korea
| | - Bong-Gyu Mun
- Laboratory of Plant Molecular Pathology and Functional Genomics, Department of Plant Biosciences, School of Applied Biosciences, College of Agriculture and Life Science, Kyungpook National University, Daegu, South Korea
| | - Da-Sol Lee
- Laboratory of Plant Molecular Pathology and Functional Genomics, Department of Plant Biosciences, School of Applied Biosciences, College of Agriculture and Life Science, Kyungpook National University, Daegu, South Korea
| | - Murtaza Khan
- Laboratory of Plant Molecular Pathology and Functional Genomics, Department of Plant Biosciences, School of Applied Biosciences, College of Agriculture and Life Science, Kyungpook National University, Daegu, South Korea
| | - Geun-Mo Lee
- Laboratory of Plant Molecular Pathology and Functional Genomics, Department of Plant Biosciences, School of Applied Biosciences, College of Agriculture and Life Science, Kyungpook National University, Daegu, South Korea
| | - Adil Hussain
- Department of Entomology, Abdul Wali Khan University, Mardan, Pakistan
| | - Byung-Wook Yun
- Laboratory of Plant Molecular Pathology and Functional Genomics, Department of Plant Biosciences, School of Applied Biosciences, College of Agriculture and Life Science, Kyungpook National University, Daegu, South Korea
| |
Collapse
|
15
|
Vishwakarma K, Kumar N, Shandilya C, Mohapatra S, Bhayana S, Varma A. Revisiting Plant-Microbe Interactions and Microbial Consortia Application for Enhancing Sustainable Agriculture: A Review. Front Microbiol 2020; 11:560406. [PMID: 33408698 PMCID: PMC7779480 DOI: 10.3389/fmicb.2020.560406] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 11/23/2020] [Indexed: 12/20/2022] Open
Abstract
The present scenario of agricultural sector is dependent hugely on the use of chemical-based fertilizers and pesticides that impact the nutritional quality, health status, and productivity of the crops. Moreover, continuous release of these chemical inputs causes toxic compounds such as metals to accumulate in the soil and move to the plants with prolonged exposure, which ultimately impact the human health. Hence, it becomes necessary to bring out the alternatives to chemical pesticides/fertilizers for improvement of agricultural outputs. The rhizosphere of plant is an important niche with abundant microorganisms residing in it. They possess the properties of plant growth promotion, disease suppression, removal of toxic compounds, and assimilating nutrients to plants. Utilizing such beneficial microbes for crop productivity presents an efficient way to modulate the crop yield and productivity by maintaining healthy status and quality of the plants through bioformulations. To understand these microbial formulation compositions, it becomes essential to understand the processes going on in the rhizosphere as well as their concrete identification for better utilization of the microbial diversity such as plant growth–promoting bacteria and arbuscular mycorrhizal fungi. Hence, with this background, the present review article highlights the plant microbiome aboveground and belowground, importance of microbial inoculants in various plant species, and their subsequent interactive mechanisms for sustainable agriculture.
Collapse
Affiliation(s)
| | - Nitin Kumar
- Department of Biotechnology, Periyar Maniammai Institute of Science and Technology, Thanjavur, India
| | | | - Swati Mohapatra
- Amity Institute of Microbial Technology, Amity University, Noida, India
| | - Sahil Bhayana
- Amity Institute of Microbial Technology, Amity University, Noida, India
| | - Ajit Varma
- Amity Institute of Microbial Technology, Amity University, Noida, India
| |
Collapse
|
16
|
Wang R, Hou D, Chen J, Li J, Fu Y, Wang S, Zheng W, Lu L, Tian S. Distinct rhizobacterial functional assemblies assist two Sedum alfredii ecotypes to adopt different survival strategies under lead stress. ENVIRONMENT INTERNATIONAL 2020; 143:105912. [PMID: 32650147 DOI: 10.1016/j.envint.2020.105912] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 06/10/2020] [Accepted: 06/11/2020] [Indexed: 06/11/2023]
Abstract
Lead (Pb) contamination presents a widespread environmental plague. Sedum alfredii is widely used for soil phytoremediation owing to its capacity to extract heavy metals, such as Pb. Although efficient Pb extraction is mediated by complex interactions between the roots and rhizospheric bacteria, the mechanism by which S. alfredii recruits microorganisms under Pb stress remains unclear. The Pb-accumulating ecotype (AE) and non-accumulating ecotype (NAE) of S. alfredii recruited different rhizobacterial communities. Under Pb stress, AE rhizosphere-enriched bacteria assembled into stable-connected clusters with higher phylogenetic and functional diversity. These microbes, e.g., Flavobacterium, could release indoleacetic acid to promote plant growth and siderophores, thereby increasing Pb availability. The NAE rhizosphere-enriched functional bacteria "desperately" assembled into highly specialized functional clusters with extremely low phylogenetic diversity. These bacteria, e.g., Pseudomonas, could enhance phosphorus solubilization and Pb precipitation, thereby reducing Pb stress and plant Pb accumulation. High niche overlap level of the rhizo-enriched species raised challenges in soil resource utilization, whereas the NAE community assembly was markedly constrained by environmental "selection effect" than that of AE rhizobacterial community. These results indicate that different ecotypes of S. alfredii recruit distinct bacterial functional assemblies to drive specific plant-soil feedbacks for different survival in Pb-contaminated soils. To cope with heavy metal stress, NAE formed a highly functional and specialized but vulnerable community and efficiently blocked heavy metal absorption by plants. However, the AE community adopted a more stable and elegant strategy to promote plant growth and the accumulation of dry matter via multiple evolutionary strategies that ensured a high yield of heavy metal phytoextraction. This for the first time provides new insights into the roles of rhizosphere microbes in plant adaptations to abiotic stresses.
Collapse
Affiliation(s)
- Runze Wang
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Dandi Hou
- School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Jiuzhou Chen
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jiahao Li
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yingyi Fu
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Sen Wang
- College of Resources and Environment, Northwest A&F University, Yangling 712100, China
| | - Wei Zheng
- College of Resources and Environment, Northwest A&F University, Yangling 712100, China
| | - Lingli Lu
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Shengke Tian
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
| |
Collapse
|
17
|
Ali A, Shaheen SM, Guo D, Li Y, Xiao R, Wahid F, Azeem M, Sohail K, Zhang T, Rinklebe J, Li R, Zhang Z. Apricot shell- and apple tree-derived biochar affect the fractionation and bioavailability of Zn and Cd as well as the microbial activity in smelter contaminated soil. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 264:114773. [PMID: 32438238 DOI: 10.1016/j.envpol.2020.114773] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 05/06/2020] [Accepted: 05/07/2020] [Indexed: 06/11/2023]
Abstract
The aim of this study was to elucidate the effects of apricot shell-derived biochar (ASB) and apple tree-derived biochar (ATB) on soil properties, plant growth, microbial communities, enzymatic activities, and Zn and Cd fractionation and phytoavailability in mining soils. Smelter soil contaminated by Zn (1860.0 mg kg-1) and Cd (39.9 mg kg-1) was collected from Fengxian, China, treated with different doses (0 (control), 1, 2.5, 5, and 10% w/w) of both biochars and cultivated by Brassica juncea in a greenhouse pot experiment. The acid-soluble, reducible, oxidizable, and residual fraction and plant tissue concentrations of Zn and Cd were determined. Biochar addition improved plant growth (22.6-29.4%), soil pH (up to 0.94 units), and soil organic matter (up to 4-fold) compared to the control. The ASB and ATB, particularly ATB, reduced the acid-soluble (21-26% for Zn and 15-35% for Cd) and the reducible (9-36% for Zn and 11-19% for Cd) fractions of Zn and Cd and altered these fractions in the organic and residual fractions. Therefore, the biochars decreased the metal concentrations in the roots (36-41% for Zn and 33-37% for Cd) and shoots (25-31% for Zn and 20-29% for Cd), which might be due to the increase in pH, biochar liming effects, and metal sorption by the biochar. The biochars impact on the bacterial community composition was selective. The ASB and ATB decreased the activities of soil β-glucosidase, dehydrogenase, and alkaline phosphatase while increasing the urease activity. The biochars, particularly ATB, can be considered as effective soil amendments for reducing the phytotoxicity of Zn and Cd in contaminated soils, improving plant growth, enhancing the abundance of specific bacterial groups and increasing urease activity; however, more attention should be paid to their negative effects on the activities of β-glucosidase, dehydrogenase, and alkaline phosphatase.
Collapse
Affiliation(s)
- Amjad Ali
- College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, China
| | - Sabry M Shaheen
- University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water- and Waste-Management, Laboratory of Soil-and Groundwater-Management, Pauluskirchstraße 7, 42285, Wuppertal, Germany; King Abdulaziz University, Faculty of Meteorology, Environment, and Arid Land Agriculture, Department of Arid Land Agriculture, Jeddah, 21589, Saudi Arabia; University of Kafrelsheikh, Faculty of Agriculture, Department of Soil and Water Sciences, Kafr El-Sheikh, 33516, Egypt
| | - Di Guo
- College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, China
| | - Yiman Li
- College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, China
| | - Ran Xiao
- College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, China
| | - Fazli Wahid
- Department of Agriculture, University of Swabi, Swabi, 23340, Pakistan
| | - Muhammad Azeem
- College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, China
| | - Kamran Sohail
- Key Laboratory of Plant Protection Resources and Pest Management of the Ministry of Education, Entomological Museum, Northwest A&F University, Yangling, 712100, China; Department of Entomology, The University of Agriculture, Peshawar, 25130, Pakistan
| | - Tao Zhang
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, Key Laboratory of Plant-Soil Interactions of Ministry of Education, Biomass Engineering Center, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China; National Institute for Green Agriculture Development, China Agricultural University, Beijing, 100193, China
| | - Jörg Rinklebe
- University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water- and Waste-Management, Laboratory of Soil-and Groundwater-Management, Pauluskirchstraße 7, 42285, Wuppertal, Germany; Department of Environment, Energy and Geoinformatics, Sejong University, Seoul, 05006, Republic of Korea
| | - Ronghua Li
- College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, China
| | - Zengqiang Zhang
- College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, China.
| |
Collapse
|
18
|
Álvarez-López V, Zappelini C, Durand A, Chalot M. Pioneer trees of Betula pendula at a red gypsum landfill harbour specific structure and composition of root-associated microbial communities. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 726:138530. [PMID: 32315851 DOI: 10.1016/j.scitotenv.2020.138530] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 04/02/2020] [Accepted: 04/05/2020] [Indexed: 06/11/2023]
Abstract
The study of root-associated microbial communities is important to understand the natural processes involved in plant recolonisation at degraded areas. Root associated bacterial and fungal communities of woody species colonising a red gypsum landfill (a metal-enriched environment) were characterised through metabarcoding. Among trees naturally growing on the landfill, Betula pendula is the only tree species in the centre of the area, whereas companion tree species such as Populus nigra, P. tremula and Salix purpurea were present on the edges. The bacterial community was dominated by Proteobacteria (38%), Actinobacteria (35%) and Bacteroidetes (20%) and the most abundant bacterial OTU belonged to the family Streptomycetaceae. The fungal community was dominated by Ascomycota (60%) and Basidiomycota (30%) and the most abundant family was Pyronemataceae. Analysis of similarities, heatmap and hierarchical cluster analysis showed that B. pendula grown in the centre of the landfill harboured a specific microbial community, which was unique and different, not only from other tree species (Populus or Salix spp.), but also from other B. pendula growing at the edges. Our findings on relevant indicator OTUs associated to the birches located in the centre of the landfill (such as Otu00716 Catellatospora sp. (family Micromonosporaceae, phylum Actinobacteria) or Otu4_35502 Russula sp. (family Russulaceae, phylum Basidiomycota)) may have important implications for the successful revegetation of these harsh environments using microbial-based phytostabilisation approaches.
Collapse
Affiliation(s)
- Vanessa Álvarez-López
- Université de Bourgogne Franche-Comté, UMR CNRS Laboratoire Chrono-environnement, Montbéliard, France.
| | - Cyril Zappelini
- Université de Bourgogne Franche-Comté, UMR CNRS Laboratoire Chrono-environnement, Montbéliard, France
| | - Alexis Durand
- Université de Bourgogne Franche-Comté, UMR CNRS Laboratoire Chrono-environnement, Montbéliard, France
| | - Michel Chalot
- Université de Bourgogne Franche-Comté, UMR CNRS Laboratoire Chrono-environnement, Montbéliard, France; Université de Lorraine, F-54000 Nancy, France
| |
Collapse
|
19
|
Wang J, Zhang X, Yao H. Optimizing ultracentrifugation conditions for DNA-based stable isotope probing (DNA-SIP). J Microbiol Methods 2020; 173:105938. [PMID: 32360380 DOI: 10.1016/j.mimet.2020.105938] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 04/24/2020] [Accepted: 04/24/2020] [Indexed: 10/24/2022]
Abstract
DNA-SIP (DNA-based stable isotope probing) is increasingly being employed in soil microbial ecology to identify those microbes assimilating the 13C/15N labelled substrate. Isopycnic gradient centrifugation is the primary experimental process for conducting DNA-SIP. However, diverse centrifugal conditions have been used in various recent studies. In order to get the optimum conditions of centrifugation for DNA-SIP, centrifugation time (36, 42, 48, 60 h), speed (45,000, 55,000 rpm) and the initial buoyant density (1.69, 1.71, 1.725 g ml-1), as were used extensively in related studies, were tested in this experiment with the Vti 65.2 rotor. DNA with either 13C-labelling or unlabelled was extracted from a paddy soil pre-incubated with either 13C-labelled or natural abundance glucose. After ultracentrifugation, the gene abundance of bacterial 16S rRNA, fungal 18S rRNA, bacterial and archaeal amoA within the fractioned DNA was detected. The results showed that centrifugation for 48 h was enough for the DNA to reach stabilization in the CsCl solution. The initial density of the mixed solution was best adjusted to 1.71 g ml-1 to ensure that most of the genes were concentrated on the middle fractions of the density gradient. Increasing the centrifugation speed would increase the density gradient of fractions; therefore, 45,000 rpm (184,000 g) was recommended so as to obtain the more widespread pattern of DNA in the centrifugal tube. We hope these findings will assist future researchers to conduct optimum ultracentrifugation for DNA-SIP.
Collapse
Affiliation(s)
- Juan Wang
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China; Key Laboratory of Urban Environmental Processes and Pollution Control, Ningbo Urban Environment Observation and Research Station, Chinese Academy of Sciences, Ningbo, China
| | - Xian Zhang
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China
| | - Huaiying Yao
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China; Key Laboratory of Urban Environmental Processes and Pollution Control, Ningbo Urban Environment Observation and Research Station, Chinese Academy of Sciences, Ningbo, China; Research Center for Environmental Ecology and Engineering, School of Environmental Ecology and Biological Engineering, Wuhan Institute of Technology, Wuhan, China.
| |
Collapse
|
20
|
Bukhat S, Imran A, Javaid S, Shahid M, Majeed A, Naqqash T. Communication of plants with microbial world: Exploring the regulatory networks for PGPR mediated defense signaling. Microbiol Res 2020; 238:126486. [PMID: 32464574 DOI: 10.1016/j.micres.2020.126486] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 03/20/2020] [Accepted: 03/28/2020] [Indexed: 02/01/2023]
Abstract
Agricultural manipulation of potentially beneficial rhizosphere microbes is increasing rapidly due to their multi-functional plant-protective and growth related benefits. Plant growth promoting rhizobacteria (PGPR) are mostly non-pathogenic microbes which exert direct benefits on plants while there are rhizosphere bacteria which indirectly help plant by ameliorating the biotic and/or abiotic stress or induction of defense response in plant. Regulation of these direct or indirect effect takes place via highly specialized communication system induced at multiple levels of interaction i.e., inter-species, intra-species, and inter-kingdom. Studies have provided insights into the functioning of signaling molecules involved in communication and induction of defense responses. Activation of host immune responses upon bacterial infection or rhizobacteria perception requires comprehensive and precise gene expression reprogramming and communication between hosts and microbes. Majority of studies have focused on signaling of host pattern recognition receptors (PRR) and nod-like receptor (NLR) and microbial effector proteins under mining the role of other components such as mitogen activated protein kinase (MAPK), microRNA, histone deacytylases. The later ones are important regulators of gene expression reprogramming in plant immune responses, pathogen virulence and communications in plant-microbe interactions. During the past decade, inoculation of PGPR has emerged as potential strategy to induce biotic and abiotic stress tolerance in plants; hence, it is imperative to expose the basis of these interactions. This review discusses microbes and plants derived signaling molecules for their communication, regulatory and signaling networks of PGPR and their different products that are involved in inducing resistance and tolerance in plants against environmental stresses and the effect of defense signaling on root microbiome. We expect that it will lead to the development and exploitation of beneficial microbes as source of crop biofertilizers in climate changing scenario enabling more sustainable agriculture.
Collapse
Affiliation(s)
- Sherien Bukhat
- Institute of Molecular Biology and Biotechnology, Bahauddin Zakariya University, 60800 Multan, Pakistan.
| | - Asma Imran
- National Institute for Biotechnology and Genetic Engineering (NIBGE), P.O. Box 577, Jhang Road, Faisalabad, Pakistan.
| | - Shaista Javaid
- Institute of Molecular Biology and Biotechnology, University of Lahore Main Campus, Defense road, Lahore, Pakistan.
| | - Muhammad Shahid
- Department of Bioinformatics and Biotechnology, Government College University Faisalabad 38000, Pakistan.
| | - Afshan Majeed
- Department of Soil and Environmental Sciences, The University of Poonch, Rawalakot, Azad Jammu and Kashmir, Pakistan.
| | - Tahir Naqqash
- Institute of Molecular Biology and Biotechnology, Bahauddin Zakariya University, 60800 Multan, Pakistan.
| |
Collapse
|
21
|
Tang L, Hamid Y, Zehra A, Sahito ZA, He Z, Khan MB, Feng Y, Yang X. Mechanisms of water regime effects on uptake of cadmium and nitrate by two ecotypes of water spinach (Ipomoea aquatica Forsk.) in contaminated soil. CHEMOSPHERE 2020; 246:125798. [PMID: 31927376 DOI: 10.1016/j.chemosphere.2019.125798] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 12/20/2019] [Accepted: 12/29/2019] [Indexed: 06/10/2023]
Abstract
Availability of cadmium (Cd) and nitrate and their transfer to green leafy vegetables is highly dependent on physical, chemical and biochemical conditions of the soil. The phenotypic characteristics, accumulation of hazardous materials and rhizosphere properties of two ecotypes of water spinach in response to water stress were investigated. Flooding significantly enhanced plant growth and decreased Cd and nitrate concentrations in the shoot and root of both ecotypes of water spinach. Flooding extensively changed the physicochemical properties and biological processes in the rhizosphere, including increased pH and activities of urease and acid phosphatase, and decreased availability of Cd and nitrate and activity of nitrate reductase. Furthermore, flooding increased rhizosphere bacteria community diversity (including richness and evenness) and changed their community structure. Denitrifying bacteria (Clostridiales, Azoarcus and Pseudomonas), toxic metal resistant microorganisms (Rhodosporillaceae, Rhizobiales and Geobacter) were enriched in the rhizosphere under flooding conditions, and the plant growth-promoting taxa (Sphingomonadaceae) were preferentially colonized in the high accumulator (HA) rhizosphere region. These results indicated that flooding treatments result in biochemical and microbiological changes in soil, especially in the rhizosphere and reduced the availability of Cd and nitrate to plants, thus decreasing their uptake by water spinach. It is, therefore, possible to promote crop growth and reduce the accumulation of hazardous materials in vegetable crops like water spinach by controlling soil moisture conditions.
Collapse
Affiliation(s)
- Lin Tang
- Ministry of Education Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, PR China
| | - Yasir Hamid
- Ministry of Education Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, PR China
| | - Afsheen Zehra
- Ministry of Education Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, PR China; Department of Botany, Federal Urdu University of Arts, Science and Technology, Karachi, Pakistan
| | - Zulfiqar Ali Sahito
- Ministry of Education Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, PR China
| | - Zhenli He
- University of Florida, Institute of Food and Agricultural Sciences, Indian River Research and Education Center, Fort Pierce, Florida, 34945, United States
| | - Muhammad Bilal Khan
- Ministry of Education Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, PR China
| | - Ying Feng
- Ministry of Education Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, PR China
| | - Xiaoe Yang
- Ministry of Education Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, PR China.
| |
Collapse
|
22
|
Wang R, Wei S, Jia P, Liu T, Hou D, Xie R, Lin Z, Ge J, Qiao Y, Chang X, Lu L, Tian S. Biochar significantly alters rhizobacterial communities and reduces Cd concentration in rice grains grown on Cd-contaminated soils. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 676:627-638. [PMID: 31051368 DOI: 10.1016/j.scitotenv.2019.04.133] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 04/07/2019] [Accepted: 04/09/2019] [Indexed: 05/27/2023]
Abstract
Cadmium (Cd) contamination poses a serious problem in paddy soils. Biochar is frequently reported to deactivate Cd in soils and reduce Cd accumulation in rice plants, but few studies have addressed whether and how biochar affected the microbial communities in rice rhizosphere, which was an important factor determining the metal bioavailability and plant growth. In this study, biochar was pyrolyzed from bamboo (Phyllostachys heterocycla) chips at 350 °C. By using ICP-MS analysis and 16S rRNA gene sequencing, the impact of the biochar on Cd uptake by rice and on rhizospheric bacterial communities was investigated in both high-accumulating (HA) and low-accumulating (LA) rice cultivars grown in soils artificially contaminated with different Cd levels. Applied biochar significantly reduced Cd contents in rice plants of both cultivars, with substantially lower grain Cd contents for LA grown in highly contaminated soil. Soil pH was slightly increased by the applied biochar. Cd bioavailability was somehow reduced in soils, but not as significant as the reduction of Cd contents in rice plants. More interestingly, biochar application significantly altered the rhizobacterial community: it stimulated growth-promoting bacteria, such as Kaistobacter, Sphingobium (order Sphingomonadales), and Rhizobiaceae (order Rhizobiales); improved natural barrier formation and the transformation of metal mobilization around the rhizosphere mediated by, e.g., Rhodocyclaceae (class Betaproteobacteria) and Geobacter (class Deltaproteobacteria); and enhanced colonization of the LA rhizosphere possibly by taxa involved in Cd immobilization (Desulfovibrionales and Desulfobacterales). These results indicate that biochar application significantly reduces Cd uptake and accumulation by altering the rhizosphere bacterial community in rice grown on Cd-contaminated soils. The baseline data generated in this study provide insights that pave the way toward safer rice production.
Collapse
Affiliation(s)
- Runze Wang
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Shuai Wei
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Peihan Jia
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Ting Liu
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Dandi Hou
- School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Ruohan Xie
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Zhi Lin
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jun Ge
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yabei Qiao
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xiaoyan Chang
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Lingli Lu
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Shengke Tian
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
| |
Collapse
|
23
|
Newitt JT, Prudence SMM, Hutchings MI, Worsley SF. Biocontrol of Cereal Crop Diseases Using Streptomycetes. Pathogens 2019; 8:pathogens8020078. [PMID: 31200493 PMCID: PMC6630304 DOI: 10.3390/pathogens8020078] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/05/2019] [Accepted: 06/09/2019] [Indexed: 12/12/2022] Open
Abstract
A growing world population and an increasing demand for greater food production requires that crop losses caused by pests and diseases are dramatically reduced. Concurrently, sustainability targets mean that alternatives to chemical pesticides are becoming increasingly desirable. Bacteria in the plant root microbiome can protect their plant host against pests and pathogenic infection. In particular, Streptomyces species are well-known to produce a range of secondary metabolites that can inhibit the growth of phytopathogens. Streptomyces are abundant in soils and are also enriched in the root microbiomes of many different plant species, including those grown as economically and nutritionally valuable cereal crops. In this review we discuss the potential of Streptomyces to protect against some of the most damaging cereal crop diseases, particularly those caused by fungal pathogens. We also explore factors that may improve the efficacy of these strains as biocontrol agents in situ, as well as the possibility of exploiting plant mechanisms, such as root exudation, that enable the recruitment of microbial species from the soil to the root microbiome. We argue that a greater understanding of these mechanisms may enable the development of protective plant root microbiomes with a greater abundance of beneficial bacteria, such as Streptomyces species.
Collapse
Affiliation(s)
- Jake T Newitt
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, Norfolk NR4 7TJ, UK.
| | - Samuel M M Prudence
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, Norfolk NR4 7TJ, UK.
| | - Matthew I Hutchings
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, Norfolk NR4 7TJ, UK.
| | - Sarah F Worsley
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, Norfolk NR4 7TJ, UK.
| |
Collapse
|
24
|
Simon L, Haichar FEZ. Determination of Root Exudate Concentration in the Rhizosphere Using 13C Labeling. Bio Protoc 2019; 9:e3228. [PMID: 33655014 PMCID: PMC7854189 DOI: 10.21769/bioprotoc.3228] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 04/11/2019] [Accepted: 04/22/2019] [Indexed: 11/02/2022] Open
Abstract
One of the most remarkable metabolic features of plant roots is their ability to secrete a wide range of compounds into the rhizosphere, defined as the volume of soil around living roots. Around 5%-21% of total photosynthetically fixed carbon is transferred into the rhizosphere through root exudates. Until recently, studies on the quantity and quality of root exudates were conducted mostly under axenic or monoxenic in vitro conditions. Today, in situ assays are required to provide a better understanding of root exudates dynamics and role in plant-microbe interactions. By incubating plants with 13CO2 in situ for one week and quantifying 13C enrichment from the root-adhering soil using mass spectrometry, we were able to determine root exudate levels. Indeed, labeled substrate 13CO2 is converted into organic carbon via plant photosynthesis and transferred into the soil through root exudation. We assume that all 13C increases above natural abundance are mainly derived from exudates produced by 13C-labeled plants.
Collapse
Affiliation(s)
- Laurent Simon
- UMR5023 LEHNA, Université Lyon 1, CNRS, ENTPE, Univ Lyon, Université Claude Bernard Lyon 1, University of Lyon, Villeurbanne Cedex, France
| | - Feth el Zahar Haichar
- UMR CNR 5557, Laboratoire d’Ecologie Microbienne, UMR INRA 1418, Univ Lyon, Université Claude Bernard Lyon 1, University of Lyon, Villeurbanne Cedex, France
| |
Collapse
|
25
|
Achouak W, Abrouk D, Guyonnet J, Barakat M, Ortet P, Simon L, Lerondelle C, Heulin T, Haichar FEZ. Plant hosts control microbial denitrification activity. FEMS Microbiol Ecol 2019; 95:5307930. [DOI: 10.1093/femsec/fiz021] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Accepted: 02/05/2019] [Indexed: 11/13/2022] Open
Affiliation(s)
- Wafa Achouak
- Aix Marseille Univ, CEA, CNRS, Laboratory for Microbial Ecology and Extreme Environment (LEMiRE), UMR7265 BVME, F-13108 Saint-Paul-lez-Durance, France
- Aix Marseille Univ, CNRS, FR 3098 ECCOREV, F-13545 Aix-en-Provence, France
| | - Danis Abrouk
- Université de Lyon, Université Lyon1, CNRS, UMR5557, INRA 1418, Ecologie Microbienne, Villeurbanne F-69622, France
| | - Julien Guyonnet
- Université de Lyon, Université Lyon1, CNRS, UMR5557, INRA 1418, Ecologie Microbienne, Villeurbanne F-69622, France
| | - Mohamed Barakat
- Aix Marseille Univ, CEA, CNRS, Laboratory for Microbial Ecology and Extreme Environment (LEMiRE), UMR7265 BVME, F-13108 Saint-Paul-lez-Durance, France
- Aix Marseille Univ, CNRS, FR 3098 ECCOREV, F-13545 Aix-en-Provence, France
| | - Philippe Ortet
- Aix Marseille Univ, CEA, CNRS, Laboratory for Microbial Ecology and Extreme Environment (LEMiRE), UMR7265 BVME, F-13108 Saint-Paul-lez-Durance, France
- Aix Marseille Univ, CNRS, FR 3098 ECCOREV, F-13545 Aix-en-Provence, France
| | - Laurent Simon
- Université de Lyon, Université Lyon 1, UMR5023 LEHNA, CNRS, ENTPE, F‐69622 Villeurbanne Cedex, France
| | - Catherine Lerondelle
- Université de Lyon, Université Lyon1, CNRS, UMR5557, INRA 1418, Ecologie Microbienne, Villeurbanne F-69622, France
| | - Thierry Heulin
- Aix Marseille Univ, CEA, CNRS, Laboratory for Microbial Ecology and Extreme Environment (LEMiRE), UMR7265 BVME, F-13108 Saint-Paul-lez-Durance, France
- Aix Marseille Univ, CNRS, FR 3098 ECCOREV, F-13545 Aix-en-Provence, France
| | - Feth el Zahar Haichar
- Université de Lyon, Université Lyon1, CNRS, UMR5557, INRA 1418, Ecologie Microbienne, Villeurbanne F-69622, France
| |
Collapse
|
26
|
Abstract
Stable isotope probing of microbial nucleic acids applied in the rhizosphere enables (a) the identification of the active microbial community involved in root exudate assimilation and those involved in soil organic matter degradation, and (b) the study of the impact of plants via root exudates on the in situ expression of microbial functions. By incubating plants under 13CO2, fresh carbon exuded by the plant will be labeled and hence the microbial community assimilating 13C-root exudates will incorporate 13C into their cellular macromolecules. Labeled DNA, RNA, and proteins can be used to identify microorganisms that assimilated the root exudates. We provide a step-by-step protocol on how to apply stable isotope probing of DNA and RNA in the plant rhizosphere to identify the active microbial communities and analyze their gene expression.
Collapse
|
27
|
Guyonnet JP, Guillemet M, Dubost A, Simon L, Ortet P, Barakat M, Heulin T, Achouak W, Haichar FEZ. Plant Nutrient Resource Use Strategies Shape Active Rhizosphere Microbiota Through Root Exudation. FRONTIERS IN PLANT SCIENCE 2018; 9:1662. [PMID: 30559748 PMCID: PMC6265440 DOI: 10.3389/fpls.2018.01662] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 10/26/2018] [Indexed: 05/20/2023]
Abstract
Plant strategies for soil nutrient uptake have the potential to strongly influence plant-microbiota interactions, due to the competition between plants and microorganisms for soil nutrient acquisition and/or conservation. In the present study, we investigate whether these plant strategies could influence rhizosphere microbial activities via root exudation, and contribute to the microbiota diversification of active bacterial communities colonizing the root-adhering soil (RAS) and inhabiting the root tissues. We applied a DNA-based stable isotope probing (DNA-SIP) approach to six grass species distributed along a gradient of plant nutrient resource strategies, from conservative species, characterized by low nitrogen (N) uptake, a long lifespans and low root exudation level, to exploitative species, characterized by high rates of photosynthesis, rapid rates of N uptake and high root exudation level. We analyzed their (i) associated microbiota composition involved in root exudate assimilation and soil organic matter (SOM) degradation by 16S-rRNA-based metabarcoding. (ii) We determine the impact of root exudation level on microbial activities (denitrification and respiration) by gas chromatography. Measurement of microbial activities revealed an increase in denitrification and respiration activities for microbial communities colonizing the RAS of exploitative species. This increase of microbial activities results probably from a higher exudation rate and more diverse metabolites by exploitative plant species. Furthermore, our results demonstrate that plant nutrient resource strategies have a role in shaping active microbiota. We present evidence demonstrating that plant nutrient use strategies shape active microbiota involved in root exudate assimilation and SOM degradation via root exudation.
Collapse
Affiliation(s)
- Julien P. Guyonnet
- Laboratoire d’Ecologie Microbienne, UMR CNRS 5557, Univ Lyon, Université Claude Bernard Lyon 1, UMR INRA 1418, Villeurbanne, France
| | - Martin Guillemet
- Laboratoire d’Ecologie Microbienne, UMR CNRS 5557, Univ Lyon, Université Claude Bernard Lyon 1, UMR INRA 1418, Villeurbanne, France
- Master de Biologie, École Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, Université de Lyon, Lyon, France
| | - Audrey Dubost
- Laboratoire d’Ecologie Microbienne, UMR CNRS 5557, Univ Lyon, Université Claude Bernard Lyon 1, UMR INRA 1418, Villeurbanne, France
| | - Laurent Simon
- CNRS, UMR 5023 LEHNA, Univ Lyon, Université Claude Bernard Lyon 1, Université Lyon 1, ENTPE, Villeurbanne, France
| | - Philippe Ortet
- CNRS, Laboratory for Microbial Ecology of the Rhizosphere and Extreme Environment, UMR 7265 BIAM, CEA, Aix Marseille Univ, Saint-Paul-lès-Durance, France
- CNRS, FR3098 ECCOREV, Aix Marseille Univ, Aix-en-Provence, France
| | - Mohamed Barakat
- CNRS, Laboratory for Microbial Ecology of the Rhizosphere and Extreme Environment, UMR 7265 BIAM, CEA, Aix Marseille Univ, Saint-Paul-lès-Durance, France
- CNRS, FR3098 ECCOREV, Aix Marseille Univ, Aix-en-Provence, France
| | - Thierry Heulin
- CNRS, Laboratory for Microbial Ecology of the Rhizosphere and Extreme Environment, UMR 7265 BIAM, CEA, Aix Marseille Univ, Saint-Paul-lès-Durance, France
- CNRS, FR3098 ECCOREV, Aix Marseille Univ, Aix-en-Provence, France
| | - Wafa Achouak
- CNRS, Laboratory for Microbial Ecology of the Rhizosphere and Extreme Environment, UMR 7265 BIAM, CEA, Aix Marseille Univ, Saint-Paul-lès-Durance, France
| | - Feth el Zahar Haichar
- Laboratoire d’Ecologie Microbienne, UMR CNRS 5557, Univ Lyon, Université Claude Bernard Lyon 1, UMR INRA 1418, Villeurbanne, France
| |
Collapse
|
28
|
Bradford LM, Vestergaard G, Táncsics A, Zhu B, Schloter M, Lueders T. Transcriptome-Stable Isotope Probing Provides Targeted Functional and Taxonomic Insights Into Microaerobic Pollutant-Degrading Aquifer Microbiota. Front Microbiol 2018; 9:2696. [PMID: 30483229 PMCID: PMC6243674 DOI: 10.3389/fmicb.2018.02696] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 10/23/2018] [Indexed: 12/21/2022] Open
Abstract
While most studies using RNA-stable isotope probing (SIP) to date have focused on ribosomal RNA, the detection of 13C-labeled mRNA has rarely been demonstrated. This approach could alleviate some of the major caveats of current non-target environmental “omics.” Here, we demonstrate the feasibility of total RNA-SIP in an experiment where hydrocarbon-degrading microbes from a BTEX-contaminated aquifer were studied in microcosms with 13C-labeled toluene under microoxic conditions. From the total sequencing reads (∼30 mio. reads per density-resolved RNA fraction), an average of 1.2% of reads per sample were identified as non-rRNA, including mRNA. Members of the Rhodocyclaceae (including those related to Quatrionicoccus spp.) were most abundant and enriched in 13C-rRNA, while well-known aerobic degraders such as Pseudomonas spp. remained unlabeled. Transcripts related to cell motility, secondary metabolite formation and xenobiotics degradation were highly labeled with 13C. mRNA of phenol hydroxylase genes were highly labeled and abundant, while other transcripts of toluene-activation were not detected. Clear labeling of catechol 2,3-dioxygenase transcripts supported previous findings that some of these extradiol dioxygenases were adapted to low oxygen concentrations. We introduce a novel combination of total RNA-SIP with calculation of transcript-specific enrichment factors (EFs) in 13C-RNA, enabling a targeted approach to process-relevant gene expression in complex microbiomes.
Collapse
Affiliation(s)
- Lauren M Bradford
- Institute of Groundwater Ecology, Helmholtz Zentrum München, Neuherberg, Germany
| | - Gisle Vestergaard
- Section of Microbiology, University of Copenhagen, Copenhagen, Denmark.,Research Unit Comparative Microbiome Analysis, Helmholtz Zentrum München, Neuherberg, Germany
| | - András Táncsics
- Regional University Center of Excellence in Environmental Industry, Szent István University, Gödöllö, Hungary
| | - Baoli Zhu
- Institute of Groundwater Ecology, Helmholtz Zentrum München, Neuherberg, Germany
| | - Michael Schloter
- Regional University Center of Excellence in Environmental Industry, Szent István University, Gödöllö, Hungary
| | - Tillmann Lueders
- Institute of Groundwater Ecology, Helmholtz Zentrum München, Neuherberg, Germany
| |
Collapse
|
29
|
Mhlongo MI, Piater LA, Madala NE, Labuschagne N, Dubery IA. The Chemistry of Plant-Microbe Interactions in the Rhizosphere and the Potential for Metabolomics to Reveal Signaling Related to Defense Priming and Induced Systemic Resistance. FRONTIERS IN PLANT SCIENCE 2018; 9:112. [PMID: 29479360 PMCID: PMC5811519 DOI: 10.3389/fpls.2018.00112] [Citation(s) in RCA: 169] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 01/22/2018] [Indexed: 05/21/2023]
Abstract
Plant roots communicate with microbes in a sophisticated manner through chemical communication within the rhizosphere, thereby leading to biofilm formation of beneficial microbes and, in the case of plant growth-promoting rhizomicrobes/-bacteria (PGPR), resulting in priming of defense, or induced resistance in the plant host. The knowledge of plant-plant and plant-microbe interactions have been greatly extended over recent years; however, the chemical communication leading to priming is far from being well understood. Furthermore, linkage between below- and above-ground plant physiological processes adds to the complexity. In metabolomics studies, the main aim is to profile and annotate all exo- and endo-metabolites in a biological system that drive and participate in physiological processes. Recent advances in this field has enabled researchers to analyze 100s of compounds in one sample over a short time period. Here, from a metabolomics viewpoint, we review the interactions within the rhizosphere and subsequent above-ground 'signalomics', and emphasize the contributions that mass spectrometric-based metabolomic approaches can bring to the study of plant-beneficial - and priming events.
Collapse
Affiliation(s)
- Msizi I. Mhlongo
- Department of Biochemistry, University of Johannesburg, Johannesburg, South Africa
| | - Lizelle A. Piater
- Department of Biochemistry, University of Johannesburg, Johannesburg, South Africa
| | - Ntakadzeni E. Madala
- Department of Biochemistry, University of Johannesburg, Johannesburg, South Africa
| | - Nico Labuschagne
- Department of Plant and Soil Sciences, University of Pretoria, Pretoria, South Africa
| | - Ian A. Dubery
- Department of Biochemistry, University of Johannesburg, Johannesburg, South Africa
| |
Collapse
|
30
|
Martin BC, Gleeson D, Statton J, Siebers AR, Grierson P, Ryan MH, Kendrick GA. Low Light Availability Alters Root Exudation and Reduces Putative Beneficial Microorganisms in Seagrass Roots. Front Microbiol 2018; 8:2667. [PMID: 29375529 PMCID: PMC5768916 DOI: 10.3389/fmicb.2017.02667] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 12/21/2017] [Indexed: 01/05/2023] Open
Abstract
Seagrass roots host a diverse microbiome that is critical for plant growth and health. Composition of microbial communities can be regulated in part by root exudates, but the specifics of these interactions in seagrass rhizospheres are still largely unknown. As light availability controls primary productivity, reduced light may impact root exudation and consequently the composition of the root microbiome. Hence, we analyzed the influence of light availability on root exudation and community structure of the root microbiome of three co-occurring seagrass species, Halophila ovalis, Halodule uninervis and Cymodocea serrulata. Plants were grown under four light treatments in mesocosms for 2 weeks; control (100% surface irradiance (SI), medium (40% SI), low (20% SI) and fluctuating light (10 days 20% and 4 days 100%). 16S rDNA amplicon sequencing revealed that microbial diversity, composition and predicted function were strongly influenced by the presence of seagrass roots, such that root microbiomes were unique to each seagrass species. Reduced light availability altered seagrass root exudation, as characterized using fluorescence spectroscopy, and altered the composition of seagrass root microbiomes with a reduction in abundance of potentially beneficial microorganisms. Overall, this study highlights the potential for above-ground light reduction to invoke a cascade of changes from alterations in root exudation to a reduction in putative beneficial microorganisms and, ultimately, confirms the importance of the seagrass root environment - a critical, but often overlooked space.
Collapse
Affiliation(s)
- Belinda C. Martin
- School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
- UWA Oceans Institute, The University of Western Australia, Crawley, WA, Australia
| | - Deirdre Gleeson
- School of Agriculture and Environment, The University of Western Australia, Crawley, WA, Australia
| | - John Statton
- School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
- UWA Oceans Institute, The University of Western Australia, Crawley, WA, Australia
- Western Australian Marine Science Institution, Perth, WA, Australia
| | - Andre R. Siebers
- School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
| | - Pauline Grierson
- School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
- West Australian Biogeochemistry Centre, School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
| | - Megan H. Ryan
- School of Agriculture and Environment, The University of Western Australia, Crawley, WA, Australia
| | - Gary A. Kendrick
- School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
- UWA Oceans Institute, The University of Western Australia, Crawley, WA, Australia
- Western Australian Marine Science Institution, Perth, WA, Australia
| |
Collapse
|
31
|
Uksa M, Buegger F, Gschwendtner S, Lueders T, Kublik S, Kautz T, Athmann M, Köpke U, Munch JC, Schloter M, Fischer D. Bacteria utilizing plant-derived carbon in the rhizosphere of Triticum aestivum change in different depths of an arable soil. ENVIRONMENTAL MICROBIOLOGY REPORTS 2017; 9:729-741. [PMID: 28892269 DOI: 10.1111/1758-2229.12588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Root exudates shape microbial communities at the plant-soil interface. Here we compared bacterial communities that utilize plant-derived carbon in the rhizosphere of wheat in different soil depths, including topsoil, as well as two subsoil layers up to 1 m depth. The experiment was performed in a greenhouse using soil monoliths with intact soil structure taken from an agricultural field. To identify bacteria utilizing plant-derived carbon, 13 C-CO2 labelling of plants was performed for two weeks at the EC50 stage, followed by isopycnic density gradient centrifugation of extracted DNA from the rhizosphere combined with 16S rRNA gene-based amplicon sequencing. Our findings suggest substantially different bacterial key players and interaction mechanisms between plants and bacteria utilizing plant-derived carbon in the rhizosphere of subsoils and topsoil. Among the three soil depths, clear differences were found in 13 C enrichment pattern across abundant operational taxonomic units (OTUs). Whereas, OTUs linked to Proteobacteria were enriched in 13 C mainly in the topsoil, in both subsoil layers OTUs related to Cohnella, Paenibacillus, Flavobacterium showed a clear 13 C signal, indicating an important, so far overseen role of Firmicutes and Bacteriodetes in the subsoil rhizosphere.
Collapse
Affiliation(s)
- Marie Uksa
- Research Unit for Comparative Microbiome Analysis, Department of Environmental Science, Helmholtz Zentrum München, D-85758 Oberschleissheim, Germany
- Soil Biology, Institute of Soil Science and Land Evaluation, University of Hohenheim, D-70599 Stuttgart, Germany
| | - Franz Buegger
- Institute of Biochemical Plant Pathology, Department of Environmental Science, Helmholtz Zentrum München, D-85758 Oberschleissheim, Germany
| | - Silvia Gschwendtner
- Research Unit for Comparative Microbiome Analysis, Department of Environmental Science, Helmholtz Zentrum München, D-85758 Oberschleissheim, Germany
| | - Tillmann Lueders
- Institute for Groundwater Ecology, Department of Environmental Science, Helmholtz Zentrum München, D-85758 Oberschleissheim, Germany
| | - Susanne Kublik
- Research Unit for Comparative Microbiome Analysis, Department of Environmental Science, Helmholtz Zentrum München, D-85758 Oberschleissheim, Germany
| | - Timo Kautz
- Institute of Organic Agriculture, University of Bonn, D-53115 Bonn, Germany
| | - Miriam Athmann
- Institute of Organic Agriculture, University of Bonn, D-53115 Bonn, Germany
| | - Ulrich Köpke
- Institute of Organic Agriculture, University of Bonn, D-53115 Bonn, Germany
| | - Jean Charles Munch
- Soil Biology, Institute of Soil Science and Land Evaluation, University of Hohenheim, D-70599 Stuttgart, Germany
| | - Michael Schloter
- Research Unit for Comparative Microbiome Analysis, Department of Environmental Science, Helmholtz Zentrum München, D-85758 Oberschleissheim, Germany
- Chair for Soil Science, Research Department Ecology and Ecosystem Management, Technische Universität München, D-85350 Freising-Weihenstephan, Germany
| | - Doreen Fischer
- Research Unit for Comparative Microbiome Analysis, Department of Environmental Science, Helmholtz Zentrum München, D-85758 Oberschleissheim, Germany
| |
Collapse
|
32
|
Gkarmiri K, Mahmood S, Ekblad A, Alström S, Högberg N, Finlay R. Identifying the Active Microbiome Associated with Roots and Rhizosphere Soil of Oilseed Rape. Appl Environ Microbiol 2017; 83:e01938-17. [PMID: 28887416 PMCID: PMC5666129 DOI: 10.1128/aem.01938-17] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Accepted: 09/06/2017] [Indexed: 12/21/2022] Open
Abstract
RNA stable isotope probing and high-throughput sequencing were used to characterize the active microbiomes of bacteria and fungi colonizing the roots and rhizosphere soil of oilseed rape to identify taxa assimilating plant-derived carbon following 13CO2 labeling. Root- and rhizosphere soil-associated communities of both bacteria and fungi differed from each other, and there were highly significant differences between their DNA- and RNA-based community profiles. Verrucomicrobia, Proteobacteria, Planctomycetes, Acidobacteria, Gemmatimonadetes, Actinobacteria, and Chloroflexi were the most active bacterial phyla in the rhizosphere soil. Bacteroidetes were more active in roots. The most abundant bacterial genera were well represented in both the 13C- and 12C-RNA fractions, while the fungal taxa were more differentiated. Streptomyces, Rhizobium, and Flavobacterium were dominant in roots, whereas Rhodoplanes and Sphingomonas (Kaistobacter) were dominant in rhizosphere soil. "Candidatus Nitrososphaera" was enriched in 13C in rhizosphere soil. Olpidium and Dendryphion were abundant in the 12C-RNA fraction of roots; Clonostachys was abundant in both roots and rhizosphere soil and heavily 13C enriched. Cryptococcus was dominant in rhizosphere soil and less abundant, but was 13C enriched in roots. The patterns of colonization and C acquisition revealed in this study assist in identifying microbial taxa that may be superior competitors for plant-derived carbon in the rhizosphere of Brassica napusIMPORTANCE This microbiome study characterizes the active bacteria and fungi colonizing the roots and rhizosphere soil of Brassica napus using high-throughput sequencing and RNA-stable isotope probing. It identifies taxa assimilating plant-derived carbon following 13CO2 labeling and compares these with other less active groups not incorporating a plant assimilate. Brassica napus is an economically and globally important oilseed crop, cultivated for edible oil, biofuel production, and phytoextraction of heavy metals; however, it is susceptible to several diseases. The identification of the fungal and bacterial species successfully competing for plant-derived carbon, enabling them to colonize the roots and rhizosphere soil of this plant, should enable the identification of microorganisms that can be evaluated in more detailed functional studies and ultimately be used to improve plant health and productivity in sustainable agriculture.
Collapse
Affiliation(s)
- Konstantia Gkarmiri
- Department of Forest Mycology and Plant Pathology, Uppsala BioCenter, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Shahid Mahmood
- Department of Forest Mycology and Plant Pathology, Uppsala BioCenter, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Alf Ekblad
- School of Science and Technology, Örebro University, Örebro, Sweden
| | - Sadhna Alström
- Department of Forest Mycology and Plant Pathology, Uppsala BioCenter, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Nils Högberg
- Department of Forest Mycology and Plant Pathology, Uppsala BioCenter, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Roger Finlay
- Department of Forest Mycology and Plant Pathology, Uppsala BioCenter, Swedish University of Agricultural Sciences, Uppsala, Sweden
| |
Collapse
|
33
|
Guyonnet JP, Vautrin F, Meiffren G, Labois C, Cantarel AAM, Michalet S, Comte G, Haichar FEZ. The effects of plant nutritional strategy on soil microbial denitrification activity through rhizosphere primary metabolites. FEMS Microbiol Ecol 2017; 93:3003321. [PMID: 28334144 DOI: 10.1093/femsec/fix022] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 02/17/2017] [Indexed: 11/12/2022] Open
Abstract
The aim of this study was to determine (i) whether plant nutritional strategy affects the composition of primary metabolites exuded into the rhizosphere and (ii) the impact of exuded metabolites on denitrification activity in soil. We answered this question by analysing primary metabolite content extracted from the root-adhering soil (RAS) and the roots of three grasses representing different nutrient management strategies: conservative (Festuca paniculata), intermediate (Bromus erectus) and exploitative (Dactylis glomerata). We also investigated the impact of primary metabolites on soil microbial denitrification enzyme activity without carbon addition, comparing for each plant RAS and bulk soils. Our data show that plant nutritional strategy impacts on primary metabolite composition of root extracts or RAS. Further we show, for the first time, that RAS-extracted primary metabolites are probably better indicators to explain plant nutrient strategy than root-extracted ones. In addition, our results show that some primary metabolites present in the RAS were well correlated with soil microbial denitrification activity with positive relationships found between denitrification and the presence of some organic acids and negative ones with the presence of xylose. We demonstrated that the analysis of primary metabolites extracted from the RAS is probably more pertinent to evaluate the impact of plant on soil microbial community functioning.
Collapse
|
34
|
van der Meij A, Worsley SF, Hutchings MI, van Wezel GP. Chemical ecology of antibiotic production by actinomycetes. FEMS Microbiol Rev 2017; 41:392-416. [DOI: 10.1093/femsre/fux005] [Citation(s) in RCA: 220] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 02/02/2017] [Indexed: 12/13/2022] Open
|
35
|
Jameson E, Taubert M, Coyotzi S, Chen Y, Eyice Ö, Schäfer H, Murrell JC, Neufeld JD, Dumont MG. DNA-, RNA-, and Protein-Based Stable-Isotope Probing for High-Throughput Biomarker Analysis of Active Microorganisms. Methods Mol Biol 2017; 1539:57-74. [PMID: 27900684 DOI: 10.1007/978-1-4939-6691-2_5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Stable-isotope probing (SIP) enables researchers to target active populations within complex microbial communities, which is achieved by providing growth substrates enriched in heavy isotopes, usually in the form of 13C, 18O, or 15N. After growth on the substrate and subsequent extraction of microbial biomarkers, typically nucleic acids or proteins, the SIP technique is used for the recovery and analysis of isotope-labeled biomarkers from active microbial populations. In the years following the initial development of DNA- and RNA-based SIP, it was common practice to characterize labeled populations by targeted gene analysis. Such approaches usually involved fingerprint-based analyses or sequencing of clone libraries containing 16S rRNA genes or functional marker gene amplicons. Although molecular fingerprinting remains a valuable approach for rapid confirmation of isotope labeling, recent advances in sequencing technology mean that it is possible to obtain affordable and comprehensive amplicon profiles, metagenomes, or metatranscriptomes from SIP experiments. Not only can the abundance of microbial groups be inferred from metagenomes, but researchers can bin, assemble, and explore individual genomes to build hypotheses about the metabolic capabilities of labeled microorganisms. Analysis of labeled mRNA is a more recent advance that can provide independent metatranscriptome-based analysis of active microorganisms. The power of metatranscriptomics is that mRNA abundance often correlates closely with the corresponding activity of encoded enzymes, thus providing insight into microbial metabolism at the time of sampling. Together, these advances have improved the sensitivity of SIP methods and allow the use of labeled substrates at ecologically relevant concentrations. Particularly as methods improve and costs continue to drop, we expect that the integration of SIP with multiple omics-based methods will become prevalent components of microbial ecology studies, leading to further breakthroughs in our understanding of novel microbial populations and elucidation of the metabolic function of complex microbial communities. In this chapter we provide protocols for obtaining labeled DNA, RNA, and proteins that can be used for downstream omics-based analyses.
Collapse
Affiliation(s)
- Eleanor Jameson
- School of Life Sciences, University of Warwick, Coventry, UK
| | - Martin Taubert
- Institute of Ecology, Friedrich Schiller University Jena, Jena, Germany
| | - Sara Coyotzi
- Department of Biology, University of Waterloo, Waterloo, ON, Canada
| | - Yin Chen
- School of Life Sciences, University of Warwick, Coventry, UK
| | - Özge Eyice
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK
| | - Hendrik Schäfer
- School of Life Sciences, University of Warwick, Coventry, UK
| | - J Colin Murrell
- School of Environmental Sciences, University of East Anglia, Norwich, UK
| | - Josh D Neufeld
- Department of Biology, University of Waterloo, Waterloo, ON, Canada
| | - Marc G Dumont
- Centre for Biological Sciences, University of Southampton, Southampton, SO17 1BJ, UK.
| |
Collapse
|
36
|
Lueders T, Dumont MG, Bradford L, Manefield M. RNA-stable isotope probing: from carbon flow within key microbiota to targeted transcriptomes. Curr Opin Biotechnol 2016; 41:83-89. [PMID: 27269505 DOI: 10.1016/j.copbio.2016.05.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 04/27/2016] [Accepted: 05/05/2016] [Indexed: 10/21/2022]
Abstract
Stable isotope probing of RNA has enthused researchers right from its first introduction in 2002. The concept of a labelling-based detection of process-targeted microbes independent of cellular replication or growth has allowed for a much more direct handle on functionally relevant microbiota than by labelling of other biomarkers. This has led to a widespread application of the technology, and breakthroughs in our understanding of carbon flow in natural microbiomes, autotrophic and heterotrophic physiologies, microbial food webs, host-microbe interactions and environmental biotechnology. Recent studies detecting labelled mRNA demonstrate that RNA-SIP is not limited to the analysis of rRNA, but is currently developing towards an approach for accessing targeted transcriptomes. In combination with next-generation sequencing and other methodological advances, RNA-SIP will continue to deliver invaluable insights into the functioning of microbial communities.
Collapse
Affiliation(s)
- Tillmann Lueders
- Helmholtz Zentrum München - German Research Center for Environmental Health, Institute for Groundwater Ecology, Neuherberg, Germany.
| | - Marc G Dumont
- Centre for Biological Sciences (CfBS), University of Southampton, Southampton, United Kingdom
| | - Lauren Bradford
- Helmholtz Zentrum München - German Research Center for Environmental Health, Institute for Groundwater Ecology, Neuherberg, Germany
| | - Mike Manefield
- Centre for Marine Bioinnovation, School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia
| |
Collapse
|
37
|
Haichar FEZ, Heulin T, Guyonnet JP, Achouak W. Stable isotope probing of carbon flow in the plant holobiont. Curr Opin Biotechnol 2016; 41:9-13. [PMID: 27019410 DOI: 10.1016/j.copbio.2016.02.023] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2015] [Revised: 02/19/2016] [Accepted: 02/23/2016] [Indexed: 01/27/2023]
Abstract
Microbial communities associated with a plant host, constituting a holobiont, affect the physiology and growth of the plant via metabolites that are mainly derived from their photosynthates. The structure and function of active microbial communities that assimilate root exudates can be tracked by using stable isotope probing (SIP) approaches. This article reviews results from ongoing SIP research in plant-microbe interactions, with a specific focus on investigating the fate of fresh and recalcitrant carbon in the rhizosphere with 13C enriched-root exudates, in addition to identifying key players in carbon cycling. Finally, we discuss new SIP applications that have the potential to identify novel enzymes implicated in rhizoremediation or plant genes dedicated to root exudation by combining SIP approaches and genome wide associations studies.
Collapse
Affiliation(s)
- Feth El Zahar Haichar
- Université Lyon1, CNRS, UMR5557, INRA, USC1364, Ecologie Microbienne, 69622 Villeurbanne, France.
| | - Thierry Heulin
- Laboratory of Microbial Ecology of the Rhizosphere and Extreme Environments (LEMIRE), Aix-Marseille Université, CEA, CNRS, UMR 7265 Biosciences and biotechnology Institute of Aix-Marseille (BIAM), ECCOREV FR 3098, CEA/Cadarache, St-Paul-lez-Durance, France
| | - Julien P Guyonnet
- Université Lyon1, CNRS, UMR5557, INRA, USC1364, Ecologie Microbienne, 69622 Villeurbanne, France
| | - Wafa Achouak
- Laboratory of Microbial Ecology of the Rhizosphere and Extreme Environments (LEMIRE), Aix-Marseille Université, CEA, CNRS, UMR 7265 Biosciences and biotechnology Institute of Aix-Marseille (BIAM), ECCOREV FR 3098, CEA/Cadarache, St-Paul-lez-Durance, France
| |
Collapse
|
38
|
Oburger E, Schmidt H. New Methods To Unravel Rhizosphere Processes. TRENDS IN PLANT SCIENCE 2016; 21:243-255. [PMID: 26776474 DOI: 10.1016/j.tplants.2015.12.005] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 12/01/2015] [Accepted: 12/09/2015] [Indexed: 05/19/2023]
Abstract
Root-triggered processes (growth, uptake and release of solutes) vary in space and time, and interact with heterogeneous soil microenvironments that provide habitats for (micro)biota on various scales. Despite tremendous progress in method development in the past decades, finding a suitable experimental set-up to investigate processes occurring at the dynamic conjunction of biosphere, hydrosphere, and pedosphere in the close vicinity of active plant roots still represents a major challenge. We discuss recent methodological developments in rhizosphere research with a focus on imaging techniques. We further review established concepts that have been updated with novel techniques, highlighting the need for combinatorial approaches to disentangle rhizosphere processes on relevant scales.
Collapse
Affiliation(s)
- Eva Oburger
- University of Natural Resources and Life Sciences Vienna, Department of Forest and Soil Sciences, Institute of Soil Research, Konrad-Lorenz Strasse 24, 3430 Tulln, Austria.
| | - Hannes Schmidt
- University of Vienna, Research Network 'Chemistry meets Microbiology', Department of Microbiology and Ecosystem Science, Division of Microbial Ecology, Althanstrasse 14, 1090 Vienna, Austria.
| |
Collapse
|
39
|
Uksa M, Schloter M, Endesfelder D, Kublik S, Engel M, Kautz T, Köpke U, Fischer D. Prokaryotes in Subsoil-Evidence for a Strong Spatial Separation of Different Phyla by Analysing Co-occurrence Networks. Front Microbiol 2015; 6:1269. [PMID: 26635741 PMCID: PMC4649028 DOI: 10.3389/fmicb.2015.01269] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 10/30/2015] [Indexed: 02/03/2023] Open
Abstract
Microbial communities in soil provide a wide range of ecosystem services. On the small scale, nutrient rich hotspots in soil developed from the activities of animals or plants are important drivers for the composition of microbial communities and their functional patterns. However, in subsoil, the spatial heterogeneity of microbes with differing lifestyles has been rarely considered so far. In this study, the phylogenetic composition of the bacterial and archaeal microbiome based on 16S rRNA gene pyrosequencing was investigated in the soil compartments bulk soil, drilosphere, and rhizosphere in top- and in the subsoil of an agricultural field. With co-occurrence network analysis, the spatial separation of typically oligotrophic and copiotrophic microbes was assessed. Four bacterial clusters were identified and attributed to bulk topsoil, bulk subsoil, drilosphere, and rhizosphere. The bacterial phyla Proteobacteria and Bacteroidetes, representing mostly copiotrophic bacteria, were affiliated mainly to the rhizosphere and drilosphere—both in topsoil and subsoil. Acidobacteria, Actinobacteria, Gemmatimonadetes, Planctomycetes, and Verrucomicrobia, bacterial phyla which harbor many oligotrophic bacteria, were the most abundant groups in bulk subsoil. The bacterial core microbiome in this soil was estimated to cover 7.6% of the bacterial sequencing reads including both oligotrophic and copiotrophic bacteria. In contrast the archaeal core microbiome includes 56% of the overall archaeal diversity. Thus, the spatial variability of nutrient quality and quantity strongly shapes the bacterial community composition and their interaction in subsoil, whereas archaea build a stable backbone of the soil prokaryotes due to their low variability in the different soil compartments.
Collapse
Affiliation(s)
- Marie Uksa
- Research Unit Environmental Genomics, Department of Environmental Science, Helmholtz Zentrum München Oberschleissheim, Germany
| | - Michael Schloter
- Research Unit Environmental Genomics, Department of Environmental Science, Helmholtz Zentrum München Oberschleissheim, Germany
| | - David Endesfelder
- Scientific Computing Research Unit, Institute of Computational Biology, Helmholtz Zentrum München Oberschleissheim, Germany
| | - Susanne Kublik
- Research Unit Environmental Genomics, Department of Environmental Science, Helmholtz Zentrum München Oberschleissheim, Germany
| | - Marion Engel
- Scientific Computing Research Unit, Institute of Computational Biology, Helmholtz Zentrum München Oberschleissheim, Germany
| | - Timo Kautz
- Institute of Organic Agriculture, University of Bonn Bonn, Germany
| | - Ulrich Köpke
- Institute of Organic Agriculture, University of Bonn Bonn, Germany
| | - Doreen Fischer
- Research Unit Environmental Genomics, Department of Environmental Science, Helmholtz Zentrum München Oberschleissheim, Germany
| |
Collapse
|
40
|
Different bacterial populations associated with the roots and rhizosphere of rice incorporate plant-derived carbon. Appl Environ Microbiol 2015; 81:2244-53. [PMID: 25616793 DOI: 10.1128/aem.03209-14] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microorganisms associated with the roots of plants have an important function in plant growth and in soil carbon sequestration. Rice cultivation is the second largest anthropogenic source of atmospheric CH4, which is a significant greenhouse gas. Up to 60% of fixed carbon formed by photosynthesis in plants is transported below ground, much of it as root exudates that are consumed by microorganisms. A stable isotope probing (SIP) approach was used to identify microorganisms using plant carbon in association with the roots and rhizosphere of rice plants. Rice plants grown in Italian paddy soil were labeled with (13)CO2 for 10 days. RNA was extracted from root material and rhizosphere soil and subjected to cesium gradient centrifugation followed by 16S rRNA amplicon pyrosequencing to identify microorganisms enriched with (13)C. Thirty operational taxonomic units (OTUs) were labeled and mostly corresponded to Proteobacteria (13 OTUs) and Verrucomicrobia (8 OTUs). These OTUs were affiliated with the Alphaproteobacteria, Betaproteobacteria, and Deltaproteobacteria classes of Proteobacteria and the "Spartobacteria" and Opitutae classes of Verrucomicrobia. In general, different bacterial groups were labeled in the root and rhizosphere, reflecting different physicochemical characteristics of these locations. The labeled OTUs in the root compartment corresponded to a greater proportion of the 16S rRNA sequences (∼20%) than did those in the rhizosphere (∼4%), indicating that a proportion of the active microbial community on the roots greater than that in the rhizosphere incorporated plant-derived carbon within the time frame of the experiment.
Collapse
|
41
|
Haichar FEZ, Santaella C, Heulin T, Achouak W. Root exudates mediated interactions belowground. SOIL BIOLOGY AND BIOCHEMISTRY 2014; 77:69-80. [PMID: 0 DOI: 10.1016/j.soilbio.2014.06.017] [Citation(s) in RCA: 297] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
42
|
Gougoulias C, Clark JM, Shaw LJ. The role of soil microbes in the global carbon cycle: tracking the below-ground microbial processing of plant-derived carbon for manipulating carbon dynamics in agricultural systems. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2014; 94:2362-71. [PMID: 24425529 PMCID: PMC4283042 DOI: 10.1002/jsfa.6577] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 01/06/2014] [Accepted: 01/15/2014] [Indexed: 05/04/2023]
Abstract
It is well known that atmospheric concentrations of carbon dioxide (CO2) (and other greenhouse gases) have increased markedly as a result of human activity since the industrial revolution. It is perhaps less appreciated that natural and managed soils are an important source and sink for atmospheric CO2 and that, primarily as a result of the activities of soil microorganisms, there is a soil-derived respiratory flux of CO2 to the atmosphere that overshadows by tenfold the annual CO2 flux from fossil fuel emissions. Therefore small changes in the soil carbon cycle could have large impacts on atmospheric CO2 concentrations. Here we discuss the role of soil microbes in the global carbon cycle and review the main methods that have been used to identify the microorganisms responsible for the processing of plant photosynthetic carbon inputs to soil. We discuss whether application of these techniques can provide the information required to underpin the management of agro-ecosystems for carbon sequestration and increased agricultural sustainability. We conclude that, although crucial in enabling the identification of plant-derived carbon-utilising microbes, current technologies lack the high-throughput ability to quantitatively apportion carbon use by phylogentic groups and its use efficiency and destination within the microbial metabolome. It is this information that is required to inform rational manipulation of the plant-soil system to favour organisms or physiologies most important for promoting soil carbon storage in agricultural soil.
Collapse
Affiliation(s)
- Christos Gougoulias
- Soil Research Centre, Department of Geography and Environmental Science, School of Archaeology, Geography and Environmental Science, University of ReadingRG6 6DW, United Kingdom
| | - Joanna M Clark
- Soil Research Centre, Department of Geography and Environmental Science, School of Archaeology, Geography and Environmental Science, University of ReadingRG6 6DW, United Kingdom
| | - Liz J Shaw
- Soil Research Centre, Department of Geography and Environmental Science, School of Archaeology, Geography and Environmental Science, University of ReadingRG6 6DW, United Kingdom
| |
Collapse
|
43
|
Mao Y, Li X, Smyth EM, Yannarell AC, Mackie RI. Enrichment of specific bacterial and eukaryotic microbes in the rhizosphere of switchgrass (Panicum virgatum L.) through root exudates. ENVIRONMENTAL MICROBIOLOGY REPORTS 2014; 6:293-306. [PMID: 24983534 DOI: 10.1111/1758-2229.12152] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 01/30/2014] [Indexed: 05/09/2023]
Abstract
Identification of microbes that actively utilize root exudates is essential to understand plant-microbe interactions. To identify active root exudate-utilizing microorganisms associated with switchgrass - a potential bioenergy crop - plants were labelled in situ with (13) CO2 , and 16S and 18S rRNA genes in the (13) C-labelled rhizosphere DNA were pyrosequenced. Multi-pulse labelling for 5 days produced detectable (13) C-DNA, which was well separated from unlabelled DNA. Methylibium from the order Burkholderiales were the most heavily labelled bacteria. Pythium, Auricularia and Galerina were the most heavily labelled eukaryotic microbes. We also identified a Glomus intraradices-like species; Glomus members are arbuscular mycorrhizal fungi that are able to colonize the switchgrass root. All of these heavily labelled microorganisms were also among the most abundant species in the rhizosphere. Species belonging to Methylibium and Pythium were the most heavily labelled and the most abundant bacteria and eukaryotes in the rhizosphere of switchgrass. Our results revealed that nearly all of the dominant rhizosphere bacterial and eukaryotic microbes were able to utilize root exudates. The enrichment of microbial species in the rhizosphere is selective and mostly due to root exudation, which functions as a nutrition source, promoting the growth of these microbes.
Collapse
Affiliation(s)
- Yuejian Mao
- Energy Biosciences Institute, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA; Institute for Genomic Biology, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | | | | | | | | |
Collapse
|
44
|
Host Plant Specific Control of 2,4-Diacetylphloroglucinol Production in the Rhizosphere. AGRONOMY-BASEL 2013. [DOI: 10.3390/agronomy3040621] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
45
|
Dias ACF, Dini-Andreote F, Hannula SE, Andreote FD, Pereira e Silva MDC, Salles JF, de Boer W, van Veen J, van Elsas JD. Different selective effects on rhizosphere bacteria exerted by genetically modified versus conventional potato lines. PLoS One 2013; 8:e67948. [PMID: 23844136 PMCID: PMC3700926 DOI: 10.1371/journal.pone.0067948] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Accepted: 05/23/2013] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND In this study, we assessed the actively metabolizing bacteria in the rhizosphere of potato using two potato cultivars, i.e. the genetically-modified (GM) cultivar Modena (having tubers with altered starch content) and the near-isogenic non-GM cultivar Karnico. To achieve our aims, we pulse-labelled plants at EC90 stage with (13)C-CO2 and analysed their rhizosphere microbial communities 24 h, 5 and 12 days following the pulse. In the analyses, phospholipid fatty acid/stable isotope probing (PLFA-SIP) as well as RNA-SIP followed by reverse transcription and PCR-DGGE and clone library analysis, were used to determine the bacterial groups that actively respond to the root-released (13)C labelled carbonaceous compounds. METHODOLOGY/PRINCIPAL FINDINGS The PLFA-SIP data revealed major roles of bacteria in the uptake of root-released (13)C carbon, which grossly increased with time. Gram-negative bacteria, including members of the genera Pseudomonas and Burkholderia, were strong accumulators of the (13)C-labeled compounds at the two cultivars, whereas Gram-positive bacteria were lesser responders. PCR-DGGE analysis of cDNA produced from the two cultivar types showed that these had selected different bacterial, alpha- and betaproteobacterial communities at all time points. Moreover, an effect of time was observed, indicating dynamism in the structure of the active bacterial communities. PCR-DGGE as well as clone library analyses revealed that the main bacterial responders at cultivar Karnico were taxonomically affiliated with the genus Pseudomonas, next to Gluconacetobacter and Paracoccus. Cultivar Modena mainly attracted Burkholderia, next to Moraxella-like (Moraxellaceae family) and Sphingomonas types. CONCLUSIONS/SIGNIFICANCE Based on the use of Pseudomonas and Burkholderia as proxies for differentially-selected bacterial genera, we conclude that the selective forces exerted by potato cultivar Modena on the active bacterial populations differed from those exerted by cultivar Karnico.
Collapse
Affiliation(s)
- Armando Cavalcante Franco Dias
- Department of Microbial Ecology, Centre for Ecological and Evolutionary Studies (CEES), University of Groningen (RUG), Groningen, The Netherlands
- Department of Soil Science, ESALQ/USP, University of São Paulo, Piracicaba, Brazil
| | - Francisco Dini-Andreote
- Department of Microbial Ecology, Centre for Ecological and Evolutionary Studies (CEES), University of Groningen (RUG), Groningen, The Netherlands
- * E-mail:
| | - Silja Emilia Hannula
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands
| | | | - Michele de Cássia Pereira e Silva
- Department of Microbial Ecology, Centre for Ecological and Evolutionary Studies (CEES), University of Groningen (RUG), Groningen, The Netherlands
| | - Joana Falcão Salles
- Department of Microbial Ecology, Centre for Ecological and Evolutionary Studies (CEES), University of Groningen (RUG), Groningen, The Netherlands
| | - Wietse de Boer
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands
| | - Johannes van Veen
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands
| | - Jan Dirk van Elsas
- Department of Microbial Ecology, Centre for Ecological and Evolutionary Studies (CEES), University of Groningen (RUG), Groningen, The Netherlands
| |
Collapse
|