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Serrão CP, Ortega JCG, Rodrigues PC, de Souza CRB. Bacillus species as tools for biocontrol of plant diseases: A meta-analysis of twenty-two years of research, 2000-2021. World J Microbiol Biotechnol 2024; 40:110. [PMID: 38411743 DOI: 10.1007/s11274-024-03935-x] [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] [Received: 11/21/2023] [Accepted: 02/21/2024] [Indexed: 02/28/2024]
Abstract
The traditional way of dealing with plant diseases has been the use of chemical products, but these harm the environment and are incompatible with the global effort for sustainable development. The use of Bacillus and related species in the biological control of plant diseases is a trend in green agriculture. Many studies report the positive effect of these bacteria, but a synthesis is still necessary. So, the objective of this work is to perform a meta-analysis of Bacillus biocontrol potential and identify factors that drive its efficacy. Data were compiled from articles published in journals listed in two of the main scientific databases between 2000 and 2021. Among 6159 articles retrieved, 399 research papers met the inclusion criteria for a systematic review. Overall, Bacilli biocontrol agents reduced disease by 60% compared to control groups. Furthermore, experimental tests with higher concentrations show a strong protective effect, unlike low and single concentration essays. Biocontrol efficacy also increased when used as a protective inoculation rather than therapeutic inoculation. Inoculation directly in the fruit has a greater effect than soil drenching. The size of the effect of Bacillus-based commercial products is lower than the newly tested strains. The findings presented in this study confirm the power of Bacillus-based bioinoculants and provide valuable guidance for practitioners, researchers, and policymakers seeking effective and sustainable solutions in plant disease management.
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Affiliation(s)
- Cleyson Pantoja Serrão
- Instituto de Ciências Biológicas, Universidade Federal do Pará (UFPA), Belém, CEP 66075-110, PA, Brazil
- Programa de Pós-Graduação em Genética e Biologia Molecular, UFPA, Belém, CEP 66075-110, PA, Brazil
| | | | - Paulo Canas Rodrigues
- Departamento de Estatística, Universidade Federal da Bahia (UFBA), Salvador, CEP 40170-110, BA, Brazil
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Kulhánek M, Asrade DA, Suran P, Sedlář O, Černý J, Balík J. Plant Nutrition-New Methods Based on the Lessons of History: A Review. PLANTS (BASEL, SWITZERLAND) 2023; 12:4150. [PMID: 38140480 PMCID: PMC10747035 DOI: 10.3390/plants12244150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 12/08/2023] [Accepted: 12/10/2023] [Indexed: 12/24/2023]
Abstract
As with new technologies, plant nutrition has taken a big step forward in the last two decades. The main objective of this review is to briefly summarise the main pathways in modern plant nutrition and attract potential researchers and publishers to this area. First, this review highlights the importance of long-term field experiments, which provide us with valuable information about the effects of different applied strategies. The second part is dedicated to the new analytical technologies (tomography, spectrometry, and chromatography), intensively studied environments (rhizosphere, soil microbial communities, and enzymatic activity), nutrient relationship indexes, and the general importance of proper data evaluation. The third section is dedicated to the strategies of plant nutrition, i.e., (i) plant breeding, (ii) precision farming, (iii) fertiliser placement, (iv) biostimulants, (v) waste materials as a source of nutrients, and (vi) nanotechnologies. Finally, the increasing environmental risks related to plant nutrition, including biotic and abiotic stress, mainly the threat of soil salinity, are mentioned. In the 21st century, fertiliser application trends should be shifted to local application, precise farming, and nanotechnology; amended with ecofriendly organic fertilisers to ensure sustainable agricultural practices; and supported by new, highly effective crop varieties. To optimise agriculture, only the combination of the mentioned modern strategies supported by a proper analysis based on long-term observations seems to be a suitable pathway.
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Affiliation(s)
- Martin Kulhánek
- Department of Agro-Environmental Chemistry and Plant Nutrition, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, 165 00 Prague, Czech Republic; (D.A.A.); (P.S.); (O.S.); (J.Č.); (J.B.)
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Ujvári G, Capo L, Grassi A, Cristani C, Pagliarani I, Turrini A, Blandino M, Giovannetti M, Agnolucci M. Agronomic strategies to enhance the early vigor and yield of maize. Part I: the role of seed applied biostimulant, hybrid and starter fertilization on rhizosphere bacteria profile and diversity. FRONTIERS IN PLANT SCIENCE 2023; 14:1240310. [PMID: 38023909 PMCID: PMC10651756 DOI: 10.3389/fpls.2023.1240310] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 10/18/2023] [Indexed: 12/01/2023]
Abstract
The sustainable intensification of maize-based systems may reduce greenhouse-gas emissions and the excessive use of non-renewable inputs. Considering the key role that the microbiological fertility has on crop growth and resilience, it is worth of interest studying the role of cropping system on the rhizosphere bacterial communities, that affect soil health and biological soil fertility. In this work we monitored and characterized the diversity and composition of native rhizosphere bacterial communities during the early growth phases of two maize genotypes of different early vigor, using a nitrogen (N)-phosphorus (P) starter fertilization and a biostimulant seed treatment, in a growth chamber experiment, by polymerase chain reaction-denaturing gradient gel electrophoresis of partial 16S rRNA gene and amplicon sequencing. Cluster analyses showed that the biostimulant treatment affected the rhizosphere bacterial microbiota of the ordinary hybrid more than that of the early vigor, both at plant emergence and at the 5-leaf stage. Moreover, the diversity indices calculated from the community profiles, revealed significant effects of NP fertilization on richness and the estimated effective number of species (H2) in both maize genotypes, while the biostimulant had a positive effect on plant growth promoting community of the ordinary hybrid, both at the plant emergence and at the fifth leaf stage. Our data showed that maize genotype was the major factor shaping rhizosphere bacterial community composition suggesting that the root system of the two maize hybrids recruited a different microbiota. Moreover, for the first time, we identified at the species and genus level the predominant native bacteria associated with two maize hybrids differing for vigor. These results pave the way for further studies to be performed on the effects of cropping system and specific crop practices, considering also the application of biostimulants, on beneficial rhizosphere microorganisms.
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Affiliation(s)
- Gergely Ujvári
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - Luca Capo
- Department of Agriculture, Forest and Food Sciences, University of Turin, Grugliasco, Italy
| | - Arianna Grassi
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - Caterina Cristani
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - Irene Pagliarani
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - Alessandra Turrini
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - Massimo Blandino
- Department of Agriculture, Forest and Food Sciences, University of Turin, Grugliasco, Italy
| | - Manuela Giovannetti
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - Monica Agnolucci
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
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Pagliarini E, Gaggìa F, Quartieri M, Toselli M, Di Gioia D. Yield and Nutraceutical Value of Lettuce and Basil Improved by a Microbial Inoculum in Greenhouse Experiments. PLANTS (BASEL, SWITZERLAND) 2023; 12:1700. [PMID: 37111923 PMCID: PMC10145599 DOI: 10.3390/plants12081700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/30/2023] [Accepted: 02/13/2023] [Indexed: 06/19/2023]
Abstract
Members of Bacillus spp. have been widely used to enrich the soil/root interface to provide plant growth promoting activities. A new isolate, namely to Bacillus sp. VWC18, has been tested under greenhouse conditions in lettuce (Lactuca sativa L.) pots at different concentrations (103, 105, 107, and 109 CFU·mL-1) and application time (single inoculum at transplant and multiple inoculum every ten days) to evaluate the best application dose and frequency. Analysis of foliar yield, main nutrients, and minerals evidenced a significant response for all applications. The lowest (103 CFU·mL-1) and the highest doses (109 CFU·mL-1), applied every ten days until harvest, had the greatest efficacy; the nutrient yield (N, K, P, Na, Ca, Fe, Mg, Mn, Cu, and B) increased more than twice. A new randomized block design with three replicates was then performed in lettuce and basil (Ocinum basilicum L.), with the two best performing concentrations applied every ten days. In addition to previous analysis, root weight, chlorophyll, and carotenoids were also examined. Both experiments confirmed the previous results: inoculation of the substrate with Bacillus sp. VWC18 promoted plant growth, chlorophyll, and mineral uptake in both crop species. Root weight duplicated or triplicated compared to control plants, and chlorophyll concentration reached even higher values. Both parameters had a dose-dependent increase.
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Canfora L, Tartanus M, Manfredini A, Tkaczuk C, Majchrowska-Safaryan A, Malusà E. The impact of Beauveria species bioinocula on the soil microbial community structure in organic strawberry plantations. Front Microbiol 2023; 13:1073386. [PMID: 36713158 PMCID: PMC9874679 DOI: 10.3389/fmicb.2022.1073386] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 12/19/2022] [Indexed: 01/13/2023] Open
Abstract
Introduction The multifunctionality of microorganisms, including entomopathogenic fungi, represents a feature that could be exploited to support the development, marketing, and application of microbial-based products for plant protection. However, it is likely that this feature could affect the composition and dynamics of the resident soil microorganisms, possibly over a longer period. Therefore, the methodology utilized to evaluate such impact is critical for a reliable assessment. The present study was performed to evaluate the impact of strains of Beauveria brongniartii and Beauveria bassiana on soil bacterial and fungal communities using an approach based on the terminal restriction fragment polymorphism (T-RFLP) analysis. Materials and methods Soil samples in the vicinity of the root system were collected during a 3-year period, before and after the bioinocula application, in two organic strawberry plantations. Specific primers were used for the amplification of the bacterial 16S rRNA gene and the fungal ITS region of the ribosome. Results and discussion Data of the profile analysis from T-RFLP analysis were used to compare the operational taxonomic unit (OTU) occurrence and intensity in the inoculated soil with the uninoculated control. With regard to the impact on the bacterial community, both Beauveria species were not fully consistently affecting their composition across the seasons and fields tested. Nevertheless, some common patterns were pointed out in each field and, sometimes, also among them when considering the time elapsed from the bioinoculum application. The impact was even more inconsistent when analyzing the fungal community. It is thus concluded that the application of the bioinocula induced only a transient and limited effect on the soil microbial community, even though some changes in the structure dynamic and frequency of soil bacterial and fungal OTUs emerged.
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Affiliation(s)
- Loredana Canfora
- Centre for Agriculture and Environment (CREA-AA), Council for Agricultural Research and Economics, Rome, Italy,*Correspondence: Loredana Canfora,
| | - Małgorzata Tartanus
- Centre for Agriculture and Environment (CREA-AA), Council for Agricultural Research and Economics, Rome, Italy,Department of Plant Protection, National Institute of Horticultural Research, Skierniewice, Poland
| | - Andrea Manfredini
- Centre for Agriculture and Environment (CREA-AA), Council for Agricultural Research and Economics, Rome, Italy
| | - Cezary Tkaczuk
- Institute of Agriculture and Horticulture, Siedlce University of Natural Sciences and Humanities, Siedlce, Poland
| | - Anna Majchrowska-Safaryan
- Institute of Agriculture and Horticulture, Siedlce University of Natural Sciences and Humanities, Siedlce, Poland
| | - Eligio Malusà
- Department of Plant Protection, National Institute of Horticultural Research, Skierniewice, Poland,Eligio Malusà,
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Morcillo RJL, Baroja-Fernández E, López-Serrano L, Leal-López J, Muñoz FJ, Bahaji A, Férez-Gómez A, Pozueta-Romero J. Cell-free microbial culture filtrates as candidate biostimulants to enhance plant growth and yield and activate soil- and plant-associated beneficial microbiota. FRONTIERS IN PLANT SCIENCE 2022; 13:1040515. [PMID: 36618653 PMCID: PMC9816334 DOI: 10.3389/fpls.2022.1040515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 12/05/2022] [Indexed: 06/12/2023]
Abstract
In this work we compiled information on current and emerging microbial-based fertilization practices, especially the use of cell-free microbial culture filtrates (CFs), to promote plant growth, yield and stress tolerance, and their effects on plant-associated beneficial microbiota. In addition, we identified limitations to bring microbial CFs to the market as biostimulants. In nature, plants act as metaorganisms, hosting microorganisms that communicate with the plants by exchanging semiochemicals through the phytosphere. Such symbiotic interactions are of high importance not only for plant yield and quality, but also for functioning of the soil microbiota. One environmentally sustainable practice to increasing crop productivity and/or protecting plants from (a)biotic stresses while reducing the excessive and inappropriate application of agrochemicals is based on the use of inoculants of beneficial microorganisms. However, this technology has a number of limitations, including inconsistencies in the field, specific growth requirements and host compatibility. Beneficial microorganisms release diffusible substances that promote plant growth and enhance yield and stress tolerance. Recently, evidence has been provided that this capacity also extends to phytopathogens. Consistently, soil application of microbial cell-free culture filtrates (CFs) has been found to promote growth and enhance the yield of horticultural crops. Recent studies have shown that the response of plants to soil application of microbial CFs is associated with strong proliferation of the resident beneficial soil microbiota. Therefore, the use of microbial CFs to enhance both crop yield and stress tolerance, and to activate beneficial soil microbiota could be a safe, efficient and environmentally friendly approach to minimize shortfalls related to the technology of microbial inoculation. In this review, we compile information on microbial CFs and the main constituents (especially volatile compounds) that promote plant growth, yield and stress tolerance, and their effects on plant-associated beneficial microbiota. In addition, we identify challenges and limitations for their use as biostimulants to bring them to the market and we propose remedial actions and give suggestions for future work.
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Affiliation(s)
- Rafael Jorge León Morcillo
- Institute for Mediterranean and Subtropical Horticulture “La Mayora” (IHSM), Consejo Superior de Investigaciones Científicas-Universidad de Málaga, Málaga, Spain
| | - Edurne Baroja-Fernández
- Instituto de Agrobiotecnología (IdAB), Consejo Superior de Investigaciones Científicas-Gobierno de Navarra, Nafarroa, Spain
| | - Lidia López-Serrano
- Institute for Mediterranean and Subtropical Horticulture “La Mayora” (IHSM), Consejo Superior de Investigaciones Científicas-Universidad de Málaga, Málaga, Spain
| | - Jesús Leal-López
- Institute for Mediterranean and Subtropical Horticulture “La Mayora” (IHSM), Consejo Superior de Investigaciones Científicas-Universidad de Málaga, Málaga, Spain
| | - Francisco José Muñoz
- Instituto de Agrobiotecnología (IdAB), Consejo Superior de Investigaciones Científicas-Gobierno de Navarra, Nafarroa, Spain
| | - Abdellatif Bahaji
- Instituto de Agrobiotecnología (IdAB), Consejo Superior de Investigaciones Científicas-Gobierno de Navarra, Nafarroa, Spain
| | - Alberto Férez-Gómez
- Institute for Mediterranean and Subtropical Horticulture “La Mayora” (IHSM), Consejo Superior de Investigaciones Científicas-Universidad de Málaga, Málaga, Spain
| | - Javier Pozueta-Romero
- Institute for Mediterranean and Subtropical Horticulture “La Mayora” (IHSM), Consejo Superior de Investigaciones Científicas-Universidad de Málaga, Málaga, Spain
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Becker R, Ulrich K, Behrendt U, Schneck V, Ulrich A. Genomic Characterization of Aureimonas altamirensis C2P003-A Specific Member of the Microbiome of Fraxinus excelsior Trees Tolerant to Ash Dieback. PLANTS (BASEL, SWITZERLAND) 2022; 11:3487. [PMID: 36559599 PMCID: PMC9781493 DOI: 10.3390/plants11243487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/07/2022] [Accepted: 12/09/2022] [Indexed: 06/17/2023]
Abstract
Some European ash trees show tolerance towards dieback caused by the invasive pathogen Hymenoscyphus fraxineus. The microbiome of these trees harbours a range of specific bacterial groups. One of these groups belonging to the species Aureimonas altamirensis was studied in detail by genome analysis and a plant inoculation trial. The strain group was shown to be phylogenetically distinct from clinical isolates by 16S rRNA analysis and phylogenomics. Genome analysis of a representative strain C2P003 resulted in a large number of unique gene sequences in comparison to other well-studied strains of the species. A functional analysis of the genome revealed features associated with the synthesis of exopolysaccharides, protein secretion and biofilm production as well as genes for stress adaptation, suggesting the ability of C2P003 to effectively colonize ash leaves. The inoculation of ash seedlings with C2P003 showed a significant positive effect on the plant health of the seedlings that were exposed to H. fraxineus infection. This effect was maintained over a period of three years and was accompanied by a significant shift in the bacterial microbiome composition one year after inoculation. Overall, the results indicate that C2P003 may suppress H. fraxineus in or on ash leaves via colonization resistance or indirectly by affecting the microbiome.
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Affiliation(s)
- Regina Becker
- Microbial Biogeochemistry, Research Area Landscape Functioning, Leibniz Centre for Agricultural Landscape Research (ZALF), 15374 Müncheberg, Germany
| | - Kristina Ulrich
- Institute of Forest Genetics, Johann Heinrich von Thünen Institute, 15377 Waldsieversdorf, Germany
| | - Undine Behrendt
- Microbial Biogeochemistry, Research Area Landscape Functioning, Leibniz Centre for Agricultural Landscape Research (ZALF), 15374 Müncheberg, Germany
| | - Volker Schneck
- Institute of Forest Genetics, Johann Heinrich von Thünen Institute, 15377 Waldsieversdorf, Germany
| | - Andreas Ulrich
- Microbial Biogeochemistry, Research Area Landscape Functioning, Leibniz Centre for Agricultural Landscape Research (ZALF), 15374 Müncheberg, Germany
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Klimasmith IM, Kent AD. Micromanaging the nitrogen cycle in agroecosystems. Trends Microbiol 2022; 30:1045-1055. [PMID: 35618540 DOI: 10.1016/j.tim.2022.04.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 03/29/2022] [Accepted: 04/29/2022] [Indexed: 01/13/2023]
Abstract
While large inputs of synthetic nitrogen fertilizers enable our current rate of crop production and feed a growing global population, these fertilizers come at a heavy environmental cost. Driven by microbial processes, excess applied nitrogen is lost from agroecosystems as nitrate and nitrous oxide (N2O) contaminating aquatic ecosystems and contributing to climate change. Interest in nitrogen-fixing microorganisms as an alternative to synthetic fertilizers is rapidly accelerating. Microbial inoculants offer the promise of a sustainable and affordable source of nitrogen, but the impact of inoculants on nitrogen dynamics at an ecosystem level is not fully understood. This review synthesizes recent studies on microbial inoculants as tools for nutrient management and considers the ramifications of inoculants for nitrogen transformations beyond fixation.
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Affiliation(s)
- Isaac M Klimasmith
- Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Angela D Kent
- Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
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Karpouzas DG, Vryzas Z, Martin-Laurent F. Pesticide soil microbial toxicity: setting the scene for a new pesticide risk assessment for soil microorganisms (IUPAC Technical Report). PURE APPL CHEM 2022. [DOI: 10.1515/pac-2022-0201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Pesticides constitute an integral part of modern agriculture. However, there are still concerns about their effects on non-target organisms. To address this the European Commission has imposed a stringent regulatory scheme for new pesticide compounds. Assessment of the aquatic toxicity of pesticides is based on a range of advanced tests. This does not apply to terrestrial ecosystems, where the toxicity of pesticides on soil microorganisms, is based on an outdated and crude test (N mineralization). This regulatory gap is reinforced by the recent methodological and standardization advances in soil microbial ecology. The inclusion of such standardized tools in a revised risk assessment scheme will enable the accurate estimation of the toxicity of pesticides on soil microorganisms and on associated ecosystem services. In this review we (i) summarize recent work in the assessment of the soil microbial toxicity of pesticides and point to ammonia-oxidizing microorganisms (AOM) and arbuscular mycorrhizal fungi (AMF) as most relevant bioindicator groups (ii) identify limitations in the experimental approaches used and propose mitigation solutions, (iii) identify scientific gaps and (iv) propose a new risk assessment procedure to assess the effects of pesticides on soil microorganisms.
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Affiliation(s)
- Dimitrios G. Karpouzas
- Department of Biochemistry and Biotechnology , Laboratory of Plant and Environmental Biotechnology, University of Thessaly , Viopolis 41500 , Larissa , Greece
| | - Zisis Vryzas
- Department of Agricultural Development , Democritus University of Thrace , Orestiada , Greece
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Mawarda PC, Mallon CA, Le Roux X, van Elsas JD, Salles JF. Interactions between Bacterial Inoculants and Native Soil Bacterial Community: the Case of Spore-forming Bacillus spp. FEMS Microbiol Ecol 2022; 98:6776013. [PMID: 36302145 PMCID: PMC9681130 DOI: 10.1093/femsec/fiac127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 07/21/2022] [Accepted: 10/25/2022] [Indexed: 01/21/2023] Open
Abstract
Microbial diversity can restrict the invasion and impact of alien microbes into soils via resource competition. However, this theory has not been tested on various microbial invaders with different ecological traits, particularly spore-forming bacteria. Here we investigated the survival capacity of two introduced spore-forming bacteria, Bacillus mycoides (BM) and B. pumillus (BP) and their impact on the soil microbiome niches with low and high diversity. We hypothesized that higher soil bacterial diversity would better restrict Bacillus survival via resource competition, and the invasion would alter the resident bacterial communities' niches only if inoculants do not escape competition with the soil community (e.g. through sporulation). Our findings showed that BP could not survive as viable propagules and transiently impacted the bacterial communities' niche structure. This may be linked to its poor resource usage and low growth rate. Having better resource use capacities, BM better survived in soil, though its survival was weakly related to the remaining resources left for them by the soil community. BM strongly affected the community niche structure, ultimately in less diverse communities. These findings show that the inverse diversity-invasibility relationship can be valid for some spore-forming bacteria, but only when they have sufficient resource use capacity.
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Affiliation(s)
| | - Cyrus A Mallon
- Microbial Community Ecology Cluster, expertise group GREEN, Groningen Institute of Evolutionary Life Sciences (GELIFES), University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - Xavier Le Roux
- INRAE, CNRS, Université Lyon 1, Université de Lyon, VetAgroSup, Laboratoire d'Ecologie Microbienne LEM, UMR 1418 INRAE, UMR 5557 CNRS, 69622 Villeurbanne Cedex, France
| | - Jan Dirk van Elsas
- Microbial Community Ecology Cluster, expertise group GREEN, Groningen Institute of Evolutionary Life Sciences (GELIFES), University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - Joana Falcão Salles
- Microbial Community Ecology Cluster, expertise group GREEN, Groningen Institute of Evolutionary Life Sciences (GELIFES), University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
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Alukumbura AS, Bigi A, Sarrocco S, Fernando WGD, Vannacci G, Mazzoncini M, Bakker MG. Minimal impacts on the wheat microbiome when Trichoderma gamsii T6085 is applied as a biocontrol agent to manage fusarium head blight disease. Front Microbiol 2022; 13:972016. [PMID: 36212885 PMCID: PMC9539683 DOI: 10.3389/fmicb.2022.972016] [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: 06/17/2022] [Accepted: 08/18/2022] [Indexed: 11/24/2022] Open
Abstract
Fusarium head blight (FHB) is a major fungal disease that causes severe yield and quality loss in wheat. Biological control can be integrated with other management strategies to control FHB. For this purpose, Trichoderma gamsii strain T6085 is a potential biocontrol agent to limit the infection of F. graminearum and F. culmorum in wheat. However, the possible impacts of T. gamsii T6085 on the broader microbiome associated with the wheat plant are not currently understood. Therefore, we identified bacteria and fungi associated with different wheat tissues, including assessment of their relative abundances and dynamics in response to the application of T6085 and over time, using amplicon sequencing. Residues of the prior year’s wheat crop and the current year’s wheat spikes were collected at multiple time points, and kernel samples were collected at harvest. DNA was extracted from the collected wheat tissues, and amplicon sequencing was performed to profile microbiomes using 16S v4 rRNA amplicons for bacteria and ITS2 amplicons for fungi. Quantitative PCR was performed to evaluate the absolute abundances of F. graminearum and T. gamsii in different wheat tissues. Disease progression was tracked visually during the growing season, revealing that FHB severity and incidence were significantly reduced when T6085 was applied to wheat spikes at anthesis. However, treatment with T6085 did not lessen the F. graminearum abundance in wheat spikes or kernels. There were substantial changes in F. graminearum abundance over time; in crop residue, pathogen abundance was highest at the initial time point and declined over time, while in wheat spikes, pathogen abundance increased significantly over time. The predominant bacterial taxa in wheat spikes and kernels were Pseudomonas, Enterobacter, and Pantoea, while Alternaria and Fusarium were the dominant fungal groups. Although the microbiome structure changed substantially over time, there were no community-scale rearrangements due to the T6085 treatment. The work suggests several other taxa that could be explored as potential biocontrol agents to integrate with T6085 treatment. However, the timing and the type of T6085 application need to be improved to give more advantages for T6085 to colonize and reduce the F. graminearum inoculum in the field.
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Affiliation(s)
| | - Alessandro Bigi
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - Sabrina Sarrocco
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
- *Correspondence: Sabrina Sarrocco,
| | - W. G. Dilantha Fernando
- Department of Plant Science, University of Manitoba, Winnipeg, MB, Canada
- W. G. Dilantha Fernando,
| | - Giovanni Vannacci
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - Marco Mazzoncini
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
- Center of Agro-Environmental Research “Enrico Avanzi,” University of Pisa, Pisa, Italy
| | - Matthew G. Bakker
- Department of Microbiology, University of Manitoba, Winnipeg, MB, Canada
- Matthew G. Bakker,
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Bacterial inoculants as effective agents in minimizing the non-target impact of azadirachtin pesticide and promoting plant growth of Vigna radiata. Arch Microbiol 2022; 204:555. [PMID: 35962834 DOI: 10.1007/s00203-022-03162-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 07/25/2022] [Accepted: 07/29/2022] [Indexed: 11/02/2022]
Abstract
Microbes regulate soil health by negating ecological disturbances, and improve plant productivity in a sustainable manner. Indiscriminate application of pesticides creates a detrimental impact on the rhizospheric microbiota, thereby affecting soil health. Azadirachtin, earlier believed to be an environment-friendly alternative to chemical pesticides, exhibits a non-target impact on microbial communities. This study aimed to employ potent bacteria to promote the growth of mungbean plant (Vigna radiata), and mitigate the non-target impact of azadirachtin. Bacterial strains were isolated by enrichment from mungbean rhizosphere. A plant growth experiment was performed with mungbean, amended with azadirachtin to assess the impact of bacterial bioinoculants on the rhizospheric microbiota. The impact of azadirachtin on rhizospheric bacterial community was analyzed qualitatively and quantitatively by 16S rRNA PCR-DGGE and qPCR of various markers, respectively. Residual concentration of azadirachtin in the soil was estimated by HPLC. The bacterial inoculants used in combination significantly promoted plant growth and enhanced the diversity and abundance of total bacterial community in the presence of azadirachtin. Further, the abundance of specific bacterial groups (α-Proteobacteria, β-Proteobacteria, Actinobacteria, Acidobacteria, and Firmicutes) were significantly boosted. Compared to the control, the isolates significantly facilitated the reduction in residual concentration of azadirachtin in the mungbean rhizosphere. Bacterial inoculants can serve a tripartite role in reducing the stress imparted by botanical pesticides, together with promoting plant growth and enriching the rhizospheric bacterial community structure.
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Chen C, Wang M, Zhu J, Tang Y, Zhang H, Zhao Q, Jing M, Chen Y, Xu X, Jiang J, Shen Z. Long-term effect of epigenetic modification in plant-microbe interactions: modification of DNA methylation induced by plant growth-promoting bacteria mediates promotion process. MICROBIOME 2022; 10:36. [PMID: 35209943 PMCID: PMC8876431 DOI: 10.1186/s40168-022-01236-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Accepted: 01/23/2022] [Indexed: 05/15/2023]
Abstract
BACKGROUND Soil microbiomes are considered a cornerstone of the next green revolution, and plant growth-promoting bacteria (PGPB) are critical for microbiome engineering. However, taking plant-beneficial microorganisms from discovery to agricultural application remains challenging, as the mechanisms underlying the interactions between beneficial strains and plants in native soils are still largely unknown. Increasing numbers of studies have indicated that strains introduced to manipulate microbiomes are usually eliminated in soils, while others have reported that application of PGPB as inocula significantly improves plant growth. This contradiction suggests the need for a deeper understanding of the mechanisms underlying microbe-induced growth promotion. RESULTS We showed PGPB-induced long-term plant growth promotion after elimination of the PGPB inoculum in soils and explored the three-way interactions among the exogenous inoculum, indigenous microbiome, and plant, which were key elements of the plant growth-promoting process. We found the rhizosphere microbiome assembly was mainly driven by plant development and root recruitments greatly attenuated the influence of inocula on the rhizosphere microbiome. Neither changes in the rhizosphere microbiome nor colonization of inocula in roots was necessary for plant growth promotion. In roots, modification of DNA methylation in response to inoculation affects gene expression related to PGPB-induced growth promotion, and disruptions of the inoculation-induced DNA methylation patterns greatly weakened the plant growth promotion. Together, our results showed PGPB-induced DNA methylation modifications in roots mediated the promotion process and these modifications remained functional after elimination of the inoculum from the microbiome. CONCLUSION This study suggests a new mechanism in which PGPB affect DNA methylation in roots to promote plant growth, which provides important insights into microbiome-plant interactions and offers new strategies for plant microbiome engineering beyond the perspective of maintaining inoculum persistence in soils. Video abstract.
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Affiliation(s)
- Chen Chen
- College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China
- Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Miao Wang
- College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Jingzhi Zhu
- College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Yongwei Tang
- College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Hanchao Zhang
- College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Qiming Zhao
- College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Minyu Jing
- College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Yahua Chen
- College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China
- Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Xihui Xu
- College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
| | - Jiandong Jiang
- College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
| | - Zhenguo Shen
- College of Life Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China.
- Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China.
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Renoud S, Vacheron J, Abrouk D, Prigent-Combaret C, Legendre L, Muller D, Moënne-Loccoz Y. Field Site-Specific Effects of an Azospirillum Seed Inoculant on Key Microbial Functional Groups in the Rhizosphere. Front Microbiol 2022; 12:760512. [PMID: 35154023 PMCID: PMC8825484 DOI: 10.3389/fmicb.2021.760512] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 12/03/2021] [Indexed: 01/05/2023] Open
Abstract
The beneficial effects of plant growth–promoting Rhizobacteria (PGPR) entail several interaction mechanisms with the plant or with other root-associated microorganisms. These microbial functions are carried out by multiple taxa within functional groups and contribute to rhizosphere functioning. It is likely that the inoculation of additional PGPR cells will modify the ecology of these functional groups. We also hypothesized that the inoculation effects on functional groups are site specific, similarly as the PGPR phytostimulation effects themselves. To test this, we assessed in the rhizosphere of field-grown maize the effect of seed inoculation with the phytostimulatory PGPR Azospirillum lipoferum CRT1 on the size and/or diversity of selected microbial functional groups important for plant growth, using quantitative polymerase chain reaction and/or Illumina MiSeq metabarcoding. The functional groups included bacteria able to fix nitrogen (a key nutrient for plant growth), producers of 1-aminocyclopropane-1-carboxylate (ACC) deaminase (which modulate ethylene metabolism in plant and stimulate root growth), and producers of 2,4-diacetylphloroglucinol (an auxinic signal enhancing root branching). To test the hypothesis that such ecological effects were site-specific, the functional groups were monitored at three different field sites, with four sampling times over two consecutive years. Despite poor inoculant survival, inoculation enhanced maize growth. It also increased the size of functional groups in the three field sites, at the maize six-leaf and flowering stages for diazotrophs and only at flowering stage for ACC deaminase and 2,4-diacetylphloroglucinol producers. Sequencing done in the second year revealed that inoculation modified the composition of diazotrophs (and of the total bacterial community) and to a lesser extent of ACC deaminase producers. This study revealed an ecological impact that was field specific (even though a few taxa were impacted in all fields) and of unexpected magnitude with the phytostimulatory Azospirillum inoculant, when considering microbial functional groups. Further methodological developments are needed to monitor additional functional groups important for soil functioning and plant growth under optimal or stress conditions.
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Affiliation(s)
- Sébastien Renoud
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, INRAe, VetAgro Sup, UMR 5557 Ecologie Microbienne, Villeurbanne, France
| | - Jordan Vacheron
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, INRAe, VetAgro Sup, UMR 5557 Ecologie Microbienne, Villeurbanne, France
| | - Danis Abrouk
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, INRAe, VetAgro Sup, UMR 5557 Ecologie Microbienne, Villeurbanne, France
| | - Claire Prigent-Combaret
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, INRAe, VetAgro Sup, UMR 5557 Ecologie Microbienne, Villeurbanne, France
| | - Laurent Legendre
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, INRAe, VetAgro Sup, UMR 5557 Ecologie Microbienne, Villeurbanne, France.,Univ Lyon, Université de St Etienne, St Etienne, France
| | - Daniel Muller
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, INRAe, VetAgro Sup, UMR 5557 Ecologie Microbienne, Villeurbanne, France
| | - Yvan Moënne-Loccoz
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, INRAe, VetAgro Sup, UMR 5557 Ecologie Microbienne, Villeurbanne, France
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Uwaremwe C, Yue L, Wang Y, Tian Y, Zhao X, Liu Y, Zhou Q, Zhang Y, Wang R. An Endophytic Strain of Bacillus amyloliquefaciens Suppresses Fusarium oxysporum Infection of Chinese Wolfberry by Altering Its Rhizosphere Bacterial Community. Front Microbiol 2022; 12:782523. [PMID: 35069484 PMCID: PMC8767019 DOI: 10.3389/fmicb.2021.782523] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 11/25/2021] [Indexed: 11/13/2022] Open
Abstract
Root rot disease is a serious infection leading to production loss of Chinese wolfberry (Lycium barbarum). This study tested the potential for two bacterial biological control agents, Bacillus amyloliquefaciens HSB1 and FZB42, against five fungal pathogens that frequently cause root rot in Chinese wolfberry. Both HSB1 and FZB42 were found to inhibit fungal mycelial growth, in vitro and in planta, as well as to promote the growth of wolfberry seedlings. In fact, a biocontrol experiment showed efficiency of 100% with at least one treatment involving each biocontrol strain against Fusarium oxysporum. Metagenomic sequencing was used to assess bacterial community shifts in the wolfberry rhizosphere upon introduction of each biocontrol strain. Results showed that HSB1 and FZB42 differentially altered the abundances of different taxa present and positively influenced various functions of inherent wolfberry rhizosphere bacteria. This study highlights the application of biocontrol method in the suppression of fungal pathogens that cause root rot disease in wolfberry, which is useful for agricultural extension agents and commercial growers.
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Affiliation(s)
- Constantine Uwaremwe
- Gaolan Station of Agricultural and Ecological Experiment, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou, China.,CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences (CAS), Mengla, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Liang Yue
- Gaolan Station of Agricultural and Ecological Experiment, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yun Wang
- Gaolan Station of Agricultural and Ecological Experiment, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou, China.,University of Chinese Academy of Sciences, Beijing, China.,Key Laboratory of Desert and Desertification, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou, China
| | - Yuan Tian
- Gaolan Station of Agricultural and Ecological Experiment, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Xia Zhao
- Gaolan Station of Agricultural and Ecological Experiment, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yang Liu
- Gaolan Station of Agricultural and Ecological Experiment, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Qin Zhou
- Gaolan Station of Agricultural and Ecological Experiment, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yubao Zhang
- Gaolan Station of Agricultural and Ecological Experiment, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Ruoyu Wang
- Gaolan Station of Agricultural and Ecological Experiment, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou, China.,University of Chinese Academy of Sciences, Beijing, China
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Dimopoulou A, Theologidis I, Varympopi A, Papafotis D, Mermigka G, Tzima A, Panopoulos NJ, Skandalis N. Shifting Perspectives of Translational Research in Bio-Bactericides: Reviewing the Bacillus amyloliquefaciens Paradigm. BIOLOGY 2021; 10:biology10111202. [PMID: 34827195 PMCID: PMC8614995 DOI: 10.3390/biology10111202] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 11/11/2021] [Accepted: 11/15/2021] [Indexed: 11/16/2022]
Abstract
Simple Summary The continuous reduction of approved conventional microbicides, due to health concerns and the development of plant-pathogen resistance, has been urged for the use of safe alternatives in crop protection. Several beneficial bacterial species, termed biological control agents, are currently used in lieu of chemical pesticides. The approach to select such bacterial species and manufacture commercial products has been based on their biocontrol effect under optimal growth conditions, which is far from the real nutrient-limited field conditions of plant niches. It’s important to determine the complex interactions that occur among BCAs, plant host and niche microbiome to fully understand and exploit the potential of biological control agents. Furthermore, it’s crucial to acknowledge the environmental impact of their long-term use. Abstract Bacterial biological control agents (BCAs) have been increasingly used against plant diseases. The traditional approach to manufacturing such commercial products was based on the selection of bacterial species able to produce secondary metabolites that inhibit mainly fungal growth in optimal media. Such species are required to be massively produced and sustain long-term self-storage. The endpoint of this pipeline is large-scale field tests in which BCAs are handled as any other pesticide. Despite recent knowledge of the importance of BCA-host-microbiome interactions to trigger plant defenses and allow colonization, holistic approaches to maximize their potential are still in their infancy. There is a gap in scientific knowledge between experiments in controlled conditions for optimal BCA and pathogen growth and the nutrient-limited field conditions in which they face niche microbiota competition. Moreover, BCAs are considered to be safe by competent authorities and the public, with no side effects to the environment; the OneHealth impact of their application is understudied. This review summarizes the state of the art in BCA research and how current knowledge and new biotechnological tools have impacted BCA development and application. Future challenges, such as their combinational use and ability to ameliorate plant stress are also discussed. Addressing such challenges would establish their long-term use as centerfold agricultural pesticides and plant growth promoters.
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Affiliation(s)
- Anastasia Dimopoulou
- Institute of Molecular Biology and Biotechnology, FORTH, 70013 Heraklion, Greece; (A.D.); (G.M.)
| | - Ioannis Theologidis
- Laboratory of Pesticides’ Toxicology, Benaki Phytopathological Institute, 14561 Athens, Greece;
| | - Adamantia Varympopi
- Enzyme and Microbial Biotechnology Unit, Department of Biology, National and Kapodistrian University of Athens, 15784 Athens, Greece; (A.V.); (D.P.)
| | - Dimitris Papafotis
- Enzyme and Microbial Biotechnology Unit, Department of Biology, National and Kapodistrian University of Athens, 15784 Athens, Greece; (A.V.); (D.P.)
| | - Glykeria Mermigka
- Institute of Molecular Biology and Biotechnology, FORTH, 70013 Heraklion, Greece; (A.D.); (G.M.)
| | - Aliki Tzima
- Laboratory of Plant Pathology, Department of Crop Production, School of Agricultural Production Infrastructure and Environment, Faculty of Crop Science, Agricultural University of Athens, 11855 Athens, Greece;
| | - Nick J. Panopoulos
- Department of Environmental Science, Policy and Management, University of California, Berkeley, CA 94720, USA;
| | - Nicholas Skandalis
- Health Sciences Campus, Keck School of Medicine, University of Southern California, 1441 Eastlake Ave, Los Angeles, CA 90033, USA
- Correspondence:
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17
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Baroja-Fernández E, Almagro G, Sánchez-López ÁM, Bahaji A, Gámez-Arcas S, De Diego N, Dolezal K, Muñoz FJ, Climent Sanz E, Pozueta-Romero J. Enhanced Yield of Pepper Plants Promoted by Soil Application of Volatiles From Cell-Free Fungal Culture Filtrates Is Associated With Activation of the Beneficial Soil Microbiota. FRONTIERS IN PLANT SCIENCE 2021; 12:752653. [PMID: 34745186 PMCID: PMC8566893 DOI: 10.3389/fpls.2021.752653] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 09/30/2021] [Indexed: 06/12/2023]
Abstract
Plants communicate with microorganisms by exchanging chemical signals throughout the phytosphere. Such interactions are important not only for plant productivity and fitness, but also for terrestrial ecosystem functioning. It is known that beneficial microorganisms emit diffusible substances including volatile organic compounds (VOCs) that promote growth. Consistently, soil application of cell-free culture filtrates (CF) of beneficial soil and plant-associated microorganisms enhances plant growth and yield. However, how this treatment acts in plants and whether it alters the resident soil microbiota, are largely unknown. In this work we characterized the responses of pepper (Capsicum annuum L.) plants cultured under both greenhouse and open field conditions and of soil microbiota to soil application of CFs of beneficial and phytopathogenic fungi. To evaluate the contribution of VOCs occurring in the CFs to these responses, we characterized the responses of plants and of soil microbiota to application of distillates (DE) of the fungal CFs. CFs and their respective DEs contained the same potentially biogenic VOCs, and application of these extracts enhanced root growth and fruit yield, and altered the nutritional characteristics of fruits. High-throughput amplicon sequencing of bacterial 16S and fungal ITS rRNA genes of the soil microbiota revealed that the CF and DE treatments altered the microbial community compositions, and led to strong enrichment of the populations of the same beneficial bacterial and fungal taxa. Our findings show that CFs of both beneficial and phytopathogenic fungi can be used as biostimulants, and provide evidence that VOCs occurring in the fungal CFs act as mediators of the plants' responses to soil application of fungal CFs through stimulation of the beneficial soil microbiota.
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Affiliation(s)
| | - Goizeder Almagro
- Instituto de Agrobiotecnología (CSIC/Gobierno de Navarra), Nafarroa, Spain
| | | | - Abdellatif Bahaji
- Instituto de Agrobiotecnología (CSIC/Gobierno de Navarra), Nafarroa, Spain
| | - Samuel Gámez-Arcas
- Instituto de Agrobiotecnología (CSIC/Gobierno de Navarra), Nafarroa, Spain
| | - Nuria De Diego
- Centre of the Region Haná for Biotechnological and Agricultural Research, Czech Advanced Technology and Research Institute, Olomouc, Czechia
| | - Karel Dolezal
- Department of Chemical Biology, Faculty of Science, Palacký University Olomouc, Olomouc, Czechia
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences, Faculty of Science, Palacký University Olomouc, Olomouc, Czechia
| | | | | | - Javier Pozueta-Romero
- Instituto de Agrobiotecnología (CSIC/Gobierno de Navarra), Nafarroa, Spain
- Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora” (IHSM-UMA-CSIC) Campus de Teatinos, Málaga, Spain
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Abstract
Bacteriophage predation is an important factor in bacterial community dynamics and evolution. Phage-bacterium interaction has mainly been studied in lab cultures, while dynamics in natural habitats, and especially in the plant root niche, are underexplored. To better understand this process, we characterized infection of the soil bacterium Bacillus subtilis NCBI 3610 by the lytic phage SPO1 during growth in LB medium and compared it to root colonization. Resistance in vitro was primarily through modification of the phage receptor. However, this type of resistance reduced the ability to colonize the root. From a line that survived phage infection while retaining the ability to colonize the root, we identified a new phage resistance mechanism involving potassium (K+) ion influx modulation and enhanced biofilm formation. Furthermore, we show that potassium serves as a stimulator of root colonization among diverse growth-promoting bacilli species, with implications for plant health.
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19
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Gao C, Wang B, Ma GC, Zeng H. Green Fluorescent Protein-Tagged Bacillus axarquiensis TUBP1 Reduced Cotton Verticillium Wilt Incidence by Altering Soil Rhizosphere Microbial Communities. Curr Microbiol 2021; 78:3562-3576. [PMID: 34347145 DOI: 10.1007/s00284-021-02618-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 07/21/2021] [Indexed: 10/20/2022]
Abstract
Verticillium wilt is a major disease of cotton that considerably decreases yield and crop quality. Soil microbial communities play an important role in plant health. Therefore, biocontrol bacteria that regulate microbial communities in rhizosphere soil can improve plant resistance to pathogens. Previously, the antagonistic strain Bacillus axarquiensis TUBP1 was screened and found to act against Verticillium dahliae with 43% biocontrol effect in cotton fields. We studied the effect of Bacillus axarquiensis TUBP1 with a green fluorescent protein (GFP) gene marker on the microbial community structure of cotton rhizosphere soil and cotton yield and quality. Cotton Verticillium wilt incidence, soil biochemical properties, and soil bacterial and fungal communities were analyzed. Results showed that bacterial and fungal abundance in cotton rhizosphere soil was temporarily changed after applying B. axarquiensis TUBP-315GFP. However, Bacillus significantly increased, whereas V. dahliae significantly decreased. The incidence of cotton Verticillium wilt after treatment with B. axarquiensis TUBP-315GFP was significantly lower and cotton production increased by 40.6%. Our findings indicated that the application of B. axarquiensis TUBP-315GFP can change microbial community structure of cotton rhizosphere soil, leading to a reduction in the incidence of cotton Verticillium wilt and increasing cotton yield.
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Affiliation(s)
- Chang Gao
- Xinjiang Production and Construction Corps Key Laboratory of Protection and Utilization of Biological Resources in Tarim Basin, College of Life Science, Tarim University, Alar, 843300, Xinjiang, People's Republic of China
| | - Bo Wang
- Xinjiang Production and Construction Corps Key Laboratory of Protection and Utilization of Biological Resources in Tarim Basin, College of Life Science, Tarim University, Alar, 843300, Xinjiang, People's Republic of China
| | - Guo-Cai Ma
- Xinjiang Production and Construction Corps Key Laboratory of Protection and Utilization of Biological Resources in Tarim Basin, College of Life Science, Tarim University, Alar, 843300, Xinjiang, People's Republic of China
| | - Hong Zeng
- Xinjiang Production and Construction Corps Key Laboratory of Protection and Utilization of Biological Resources in Tarim Basin, College of Life Science, Tarim University, Alar, 843300, Xinjiang, People's Republic of China.
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20
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Bacillus amyloliquefaciens FH-1 significantly affects cucumber seedlings and the rhizosphere bacterial community but not soil. Sci Rep 2021; 11:12055. [PMID: 34103586 PMCID: PMC8187646 DOI: 10.1038/s41598-021-91399-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 05/21/2021] [Indexed: 11/16/2022] Open
Abstract
Plant growth-promoting bacteria (PGPB) inoculants have been applied worldwide. However, the ecological roles of PGPB under different soil conditions are still not well understood. The present study aimed to explore the ecological roles of Bacillus amyloliquefaciens FH-1 (FH) on cucumber seedlings, rhizosphere soil properties, and the bacterial community in pot experiments. The results showed that FH had significant effects on cucumber seedlings and the rhizosphere bacterial community but not on soil properties. The FH promoted cucumber seedlings growth, reduced the rhizosphere bacterial diversity, increased Proteobacteria, and decreased Acidobacteria. Linear discriminant analysis (LDA) effect size (LEfSe) revealed that FH enriched two taxa (GKS2_174 and Nannocystaceae) and inhibited 18 taxa (mainly Acidobacteria, Actinobacteria, BRC1, Chloroflexi, Plantctomycetes, and Verrucomicrobia). Co-occurrence network analysis demonstrated that FH increased bacteria-bacteria interactions and that Bacillus (genus of FH) had few interactions with the enriched and inhibited taxa. This might indicate that FH does not directly affect the enriched and inhibited taxa. Correlation analysis results displayed that cucumber seedlings’ weight and height/length (except root length) were significantly correlated with the 18 inhibited taxa and the enriched taxa Nannocystaceae. It was speculated that FH might promote cucumber seedling growth by indirectly enriching Nannocystaceae and inhibiting some taxa from Acidobacteria, Actinobacteria, BRC1, Chloroflexi, Plantctomycetes, and Verrucomicrobia.
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21
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Succession of the Resident Soil Microbial Community in Response to Periodic Inoculations. Appl Environ Microbiol 2021; 87:AEM.00046-21. [PMID: 33637572 PMCID: PMC8091015 DOI: 10.1128/aem.00046-21] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 02/11/2021] [Indexed: 12/03/2022] Open
Abstract
Introducing beneficial microbes to the plant-soil system is an environmentally friendly approach to improve the crop yield and soil environment. Numerous studies have attempted to reveal the impacts of inoculation on the rhizosphere microbiome. To maintain the beneficial effects of microbial inoculants on plants and soil, repeated inoculation represents a promising option. Until now, the impacts of one-off inoculation on the native microbiome have been explored, but it remains unclear how long and to what extent the periodic inoculations would affect the succession of the resident microbiome in bulk soil. Here, we examined the dynamic responses of plant growth, soil functions, and the resident bacterial community in the bulk soil to periodic inoculations of phosphate-solubilizing and N2-fixing bacteria alone or in combination. Compared to single-strain inoculation, coinoculation better stimulated plant growth and soil nutrients. However, the benefits from inoculants did not increase with repeated inoculations and were not maintained after transplantation to a different site. In response to microbial inoculants, three patterns of shifts in the bacterial composition were observed: fold increase, fold decrease, and resilience. The periodic inoculations impacted the succession course of resident bacterial communities in bulk soil, mainly driven by changes in soil pH and nitrate, resulting in the development of three main cluster types throughout the investigation. The single and mixed inoculants transiently modulated the variation in the resident community in association with soil pH and the C/N ratio, but finally, the community established and showed resilience to subsequent inoculations. Consequently, the necessity of repeated inoculations should be reconsidered, and while the different microbial inoculants showed distinct impacts on resident microbiome succession, the communities ultimately exhibited resilience. IMPORTANCE Introducing beneficial microbes to the plant-soil system is an environmentally friendly approach to improve the crop yield and soil environment. Numerous studies have attempted to reveal the impacts of inoculation on the rhizosphere microbiome. However, little is known about the effectiveness of periodic inoculations on soil functioning. In addition, the long-term impact of repeated inoculations on the native community remains unclear. Here, we track the succession traits of the resident microbiome in the bulk soil across a growing season and identify the taxon clusters that respond differently to periodic inoculation. Crucially, we compare the development of the resident community composition with and without inoculation, thus providing new insight into the interactions between resident microbes and intruders. Finally, we conclude that initial inoculation plays a more important role in influencing the whole system, and the native microbial community exhibits traits of resilience, but no resistance, to the subsequent inoculations.
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22
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Berg G, Kusstatscher P, Abdelfattah A, Cernava T, Smalla K. Microbiome Modulation-Toward a Better Understanding of Plant Microbiome Response to Microbial Inoculants. Front Microbiol 2021; 12:650610. [PMID: 33897663 PMCID: PMC8060476 DOI: 10.3389/fmicb.2021.650610] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 03/19/2021] [Indexed: 12/31/2022] Open
Abstract
Plant-associated microorganisms are involved in important functions related to growth, performance and health of their hosts. Understanding their modes of action is important for the design of promising microbial inoculants for sustainable agriculture. Plant-associated microorganisms are able to interact with their hosts and often exert specific functions toward potential pathogens; the underlying in vitro interactions are well studied. In contrast, in situ effects of inoculants, and especially their impact on the plant indigenous microbiome was mostly neglected so far. Recently, microbiome research has revolutionized our understanding of plants as coevolved holobionts but also of indigenous microbiome-inoculant interactions. Here we disentangle the effects of microbial inoculants on the indigenous plant microbiome and point out the following types of plant microbiome modulations: (i) transient microbiome shifts, (ii) stabilization or increase of microbial diversity, (iii) stabilization or increase of plant microbiome evenness, (iv) restoration of a dysbiosis/compensation or reduction of a pathogen-induced shift, (v) targeted shifts toward plant beneficial members of the indigenous microbiota, and (vi) suppression of potential pathogens. Therefore, we suggest microbiome modulations as novel and efficient mode of action for microbial inoculants that can also be mediated via the plant.
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Affiliation(s)
- Gabriele Berg
- Institute of Environmental Biotechnology, Graz University of Technology, Graz, Austria
| | - Peter Kusstatscher
- Institute of Environmental Biotechnology, Graz University of Technology, Graz, Austria
| | - Ahmed Abdelfattah
- Institute of Environmental Biotechnology, Graz University of Technology, Graz, Austria
| | - Tomislav Cernava
- Institute of Environmental Biotechnology, Graz University of Technology, Graz, Austria
| | - Kornelia Smalla
- Julius Kühn Institute (JKI) Federal Research Centre for Cultivated Plants, Institute for Epidemiology and Pathogen Diagnostics, Braunschweig, Germany
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Identification of Beneficial Microbial Consortia and Bioactive Compounds with Potential as Plant Biostimulants for a Sustainable Agriculture. Microorganisms 2021; 9:microorganisms9020426. [PMID: 33669534 PMCID: PMC7922931 DOI: 10.3390/microorganisms9020426] [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] [Received: 01/01/2021] [Revised: 02/07/2021] [Accepted: 02/08/2021] [Indexed: 01/28/2023] Open
Abstract
A growing body of evidence demonstrates the potential of various microbes to enhance plant productivity in cropping systems although their successful field application may be impaired by several biotic and abiotic constraints. In the present work, we aimed at developing multifunctional synthetic microbial consortia to be used in combination with suitable bioactive compounds for improving crop yield and quality. Plant growth-promoting microorganisms (PGPMs) with different functional attributes were identified by a bottom-up approach. A comprehensive literature survey on PGPMs associated with maize, wheat, potato and tomato, and on commercial formulations, was conducted by examining peer-reviewed scientific publications and results from relevant European projects. Metagenome fragment recruitments on genomes of potential PGPMs represented in databases were also performed to help identify plant growth-promoting (PGP) strains. Following evidence of their ability to coexist, isolated PGPMs were synthetically assembled into three different microbial consortia. Additionally, the effects of bioactive compounds on the growth of individually PGPMs were tested in starvation conditions. The different combination products based on microbial and non-microbial biostimulants (BS) appear worth considering for greenhouse and open field trials to select those potentially adoptable in sustainable agriculture.
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Genome mining and UHPLC-QTOF-MS/MS to identify the potential antimicrobial compounds and determine the specificity of biosynthetic gene clusters in Bacillus subtilis NCD-2. BMC Genomics 2020; 21:767. [PMID: 33153447 PMCID: PMC7643408 DOI: 10.1186/s12864-020-07160-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 10/19/2020] [Indexed: 11/24/2022] Open
Abstract
Background Bacillus subtilis strain NCD-2 is an excellent biocontrol agent against plant soil-borne diseases and shows broad-spectrum antifungal activities. This study aimed to explore some secondary metabolite biosynthetic gene clusters and related antimicrobial compounds in strain NCD-2. An integrative approach combining genome mining and structural identification technologies using ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight tandem mass spectrometry (UHPLC-MS/MS), was adopted to interpret the chemical origins of metabolites with significant biological activities. Results Genome mining revealed nine gene clusters encoding secondary metabolites with predicted functions, including fengycin, surfactin, bacillaene, subtilosin, bacillibactin, bacilysin and three unknown products. Fengycin, surfactin, bacillaene and bacillibactin were successfully detected from the fermentation broth of strain NCD-2 by UHPLC-QTOF-MS/MS. The biosynthetic gene clusters of bacillaene, subtilosin, bacillibactin, and bacilysin showed 100% amino acid sequence identities with those in B. velezensis strain FZB42, whereas the identities of the surfactin and fengycin gene clusters were only 83 and 92%, respectively. Further comparison revealed that strain NCD-2 had lost the fenC and fenD genes in the fengycin biosynthetic operon. The biosynthetic enzyme-related gene srfAB for surfactin was divided into two parts. Bioinformatics analysis suggested that FenE in strain NCD-2 had a similar function to FenE and FenC in strain FZB42, and that FenA in strain NCD-2 had a similar function to FenA and FenD in strain FZB42. Five different kinds of fengycins, with 26 homologs, and surfactin, with 4 homologs, were detected from strain NCD-2. To the best of our knowledge, this is the first report of a non-typical gene cluster related to fengycin synthesis. Conclusions Our study revealed a number of gene clusters encoding antimicrobial compounds in the genome of strain NCD-2, including a fengycin synthetic gene cluster that might be unique by using genome mining and UHPLC–QTOF–MS/MS. The production of fengycin, surfactin, bacillaene and bacillibactin might explain the biological activities of strain NCD-2. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-020-07160-2.
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BTEX biodegradation by Bacillus amyloliquefaciens subsp. plantarum W1 and its proposed BTEX biodegradation pathways. Sci Rep 2020; 10:17408. [PMID: 33060819 PMCID: PMC7562720 DOI: 10.1038/s41598-020-74570-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 08/10/2020] [Indexed: 12/04/2022] Open
Abstract
Benzene, toluene, ethylbenzene and (p-, m- and o-) xylene (BTEX) are classified as main pollutants by several environmental protection agencies. In this study, a non-pathogenic, Gram-positive rod-shape bacterium with an ability to degrade all six BTEX compounds, employed as an individual substrate or as a mixture, was isolated. The bacterial isolate was identified as Bacillus amyloliquefaciens subsp. plantarum strain W1. An overall BTEX biodegradation (as individual substrates) by strain W1 could be ranked as: toluene > benzene, ethylbenzene, p-xylene > m-xylene > o-xylene. When presented in a BTEX mixture, m-xylene and o-xylene biodegradation was slightly improved suggesting an induction effect by other BTEX components. BTEX biodegradation pathways of strain W1 were proposed based on analyses of its metabolic intermediates identified by LC–MS/MS. Detected activity of several putative monooxygenases and dioxygenases suggested the versatility of strain W1. Thus far, this is the first report of biodegradation pathways for all of the six BTEX compounds by a unique bacterium of the genus Bacillus. Moreover, B. amyloliquefaciens subsp. plantarum W1 could be a good candidate for an in situ bioremediation considering its Generally Recognized as Safe (GRAS) status and a possibility to serve as a plant growth-promoting rhizobacterium (PGPR).
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Jiménez JA, Novinscak A, Filion M. Inoculation With the Plant-Growth-Promoting Rhizobacterium Pseudomonas fluorescens LBUM677 Impacts the Rhizosphere Microbiome of Three Oilseed Crops. Front Microbiol 2020; 11:569366. [PMID: 33162951 PMCID: PMC7581686 DOI: 10.3389/fmicb.2020.569366] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 09/22/2020] [Indexed: 12/13/2022] Open
Abstract
The bacterial communities inhabiting the rhizosphere play an important role in plant development and health. Here we studied the effect of inoculation with Pseudomonas fluorescens LBUM677, a plant growth promoting rhizobacterium that promotes seed oil accumulation, on the rhizosphere microbiome of three oilseed crops (Brassica napus, Buglossoides arvensis, and Glycine max) over time. Next-Generation high-throughput sequencing targeting the V4 region of 16S rDNA was used to characterize the microbial communities associated with the three different crops, inoculated or not with LBUM677, over a time period of up to 90 days post-inoculation. A total of 1,627,231 amplicon sequence variants were obtained and were taxonomically grouped into 39 different phyla. LBUM677 inoculation and sampling date were found to significantly influence the rhizosphere microbiome of the three oil-producing crops under study. Specifically, inoculation with LBUM677 and sampling date, but not the plant species, were found to significantly alter the alpha- and the beta-diversity of the rhizosphere microbial communities. Differential abundance analyses found that 29 taxonomical bacterial groups were significantly more abundant in the LBUM677 treatments while 30 were significantly more abundant in the control treatments. Predicted functions of the microorganisms were also enriched, including 47 enzymatic pathways in LBUM677 treatments. These non-targeted effects on rhizosphere bacterial communities are discussed in the context of oilseed crops.
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Affiliation(s)
- Jesús A Jiménez
- Biology Department, Université de Moncton, Moncton, NB, Canada
| | - Amy Novinscak
- Biology Department, Université de Moncton, Moncton, NB, Canada
| | - Martin Filion
- Agriculture and Agri-Food Canada, Saint-Jean-sur-Richelieu Research and Development Center, Saint-Jean-sur-Richelieu, QC, Canada
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Tienda S, Vida C, Lagendijk E, de Weert S, Linares I, González-Fernández J, Guirado E, de Vicente A, Cazorla FM. Soil Application of a Formulated Biocontrol Rhizobacterium, Pseudomonas chlororaphis PCL1606, Induces Soil Suppressiveness by Impacting Specific Microbial Communities. Front Microbiol 2020; 11:1874. [PMID: 32849458 PMCID: PMC7426498 DOI: 10.3389/fmicb.2020.01874] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 07/16/2020] [Indexed: 12/14/2022] Open
Abstract
Biocontrol bacteria can be used for plant protection against some plant diseases. Pseudomonas chlororaphis PCL1606 (PcPCL1606) is a model bacterium isolated from the avocado rhizosphere with strong antifungal antagonism mediated by the production of 2-hexyl, 5-propil resorcinol (HPR). Additionally, PcPCL1606 has biological control against different soil-borne fungal pathogens, including the causal agent of the white root rot of many woody crops and avocado in the Mediterranean area, Rosellinia necatrix. The objective of this study was to assess whether the semicommercial application of PcPCL1606 to soil can potentially affect avocado soil and rhizosphere microbial communities and their activities in natural conditions and under R. necatrix infection. To test the putative effects of PcPCL1606 on soil eukaryotic and prokaryotic communities, a formulated PcPCL1606 was prepared and applied to the soil of avocado plants growing in mesocosm experiments, and the communities were analyzed by using 16S/ITS metagenomics. PcPCL1606 survived until the end of the experiments. The effect of PcPCL1606 application on prokaryotic communities in soil and rhizosphere samples from natural soil was not detectable, and very minor changes were observed in eukaryotic communities. In the infested soils, the presence of R. necatrix strongly impacted the soil and rhizosphere microbial communities. However, after PcPCL1606 was applied to soil infested with R. necatrix, the prokaryotic community reacted by increasing the relative abundance of few families with protective features against fungal soilborne pathogens and organic matter decomposition (Chitinophagaceae, Cytophagaceae), but no new prokaryotic families were detected. The treatment of PcPCL1606 impacted the fungal profile, which strongly reduced the presence of R. necatrix in avocado soil and rhizosphere, minimizing its effect on the rest of the microbial communities. The bacterial treatment of formulated PcPCL1606 on avocado soils infested with R. necatrix resulted in biological control of the pathogen. This suppressiveness phenotype was analyzed, and PcPCL1606 has a key role in suppressiveness induction; in addition, this phenotype was strongly dependent on the production of HPR.
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Affiliation(s)
- Sandra Tienda
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain
- Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, IHSM-UMA-CSIC, Málaga, Spain
| | - Carmen Vida
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain
- Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, IHSM-UMA-CSIC, Málaga, Spain
| | - Ellen Lagendijk
- Koppert Biological Systems, Berkel en Rodenrijs, Netherlands
| | - Sandra de Weert
- Koppert Biological Systems, Berkel en Rodenrijs, Netherlands
| | - Irene Linares
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain
- Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, IHSM-UMA-CSIC, Málaga, Spain
| | - Jorge González-Fernández
- Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, IHSM-UMA-CSIC, Estación Experimental “La Mayora”, Algarrobo, Spain
| | - Emilio Guirado
- Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, IHSM-UMA-CSIC, Estación Experimental “La Mayora”, Algarrobo, Spain
| | - Antonio de Vicente
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain
- Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, IHSM-UMA-CSIC, Málaga, Spain
| | - Francisco M. Cazorla
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain
- Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, IHSM-UMA-CSIC, Málaga, Spain
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Andrić S, Meyer T, Ongena M. Bacillus Responses to Plant-Associated Fungal and Bacterial Communities. Front Microbiol 2020; 11:1350. [PMID: 32655531 PMCID: PMC7324712 DOI: 10.3389/fmicb.2020.01350] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 05/26/2020] [Indexed: 12/22/2022] Open
Abstract
Some members of root-associated Bacillus species have been developed as biocontrol agents due to their contribution to plant protection by directly interfering with the growth of pathogens or by stimulating systemic resistance in their host. As rhizosphere-dwelling bacteria, these bacilli are surrounded and constantly interacting with other microbes via different types of communications. With this review, we provide an updated vision of the molecular and phenotypic responses of Bacillus upon sensing other rhizosphere microorganisms and/or their metabolites. We illustrate how Bacillus spp. may react by modulating the production of secondary metabolites, such as cyclic lipopeptides or polyketides. On the other hand, some developmental processes, such as biofilm formation, motility, and sporulation may also be modified upon interaction, reflecting the adaptation of Bacillus multicellular communities to microbial competitors for preserving their ecological persistence. This review also points out the limited data available and a global lack of knowledge indicating that more research is needed in order to, not only better understand the ecology of bacilli in their natural soil niche, but also to better assess and improve their promising biocontrol potential.
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Affiliation(s)
- Sofija Andrić
- Microbial Processes and Interactions Laboratory, Terra Teaching and Research Center, Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium
| | - Thibault Meyer
- Microbial Processes and Interactions Laboratory, Terra Teaching and Research Center, Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium
| | - Marc Ongena
- Microbial Processes and Interactions Laboratory, Terra Teaching and Research Center, Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium
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Wang C, Zhao D, Qi G, Mao Z, Hu X, Du B, Liu K, Ding Y. Effects of Bacillus velezensis FKM10 for Promoting the Growth of Malus hupehensis Rehd. and Inhibiting Fusarium verticillioides. Front Microbiol 2020; 10:2889. [PMID: 31998247 PMCID: PMC6965166 DOI: 10.3389/fmicb.2019.02889] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 12/02/2019] [Indexed: 11/26/2022] Open
Abstract
Bacillus velezensis is a novel species of Bacillus that has been widely investigated and used because of its direct or indirect growth improvement effect for many plants. B. velezensis FKM10 was previously isolated from rhizosphere soil of apple trees and shows potential as a plant growth-promoting and biocontrol bacterium. In this study, strain FKM10 was verified to inhibit some fungal pathogens of soil-borne plant diseases, produce siderophores to absorb ferric iron for plants, and degrade proteins. Pot experiments showed that the application of strain FKM10 could directly promote the growth of Malus hupehensis Rehd. by increasing biomass, promoting the absorption of nutrients, improving soil fertility, changing the soil microbial community structure, and reducing fungal diversity. The results of this study provided a basis for using strain FKM10 to improve crop yield and overcome diseases of plants. The mechanism of strain FKM10 to control the phytopathogenic fungus Fusarium verticillioides was studied by interoperation with RNA sequencing. Strain FKM10 can destroy the cell wall and cell membrane of F. verticillioides. The secretion of glucosidases, such as β-glucanase, might be one of the causes of the destruction of the fungal cell wall. The regulation of amino acid metabolism might also play an important role in the antibacterial process of strain FKM10. During the antibacterial process, strain FKM10 attacks F. verticillioides and strain FKM10 itself is also affected: the expression of spores is increased, the number of viable cells is decreased, and the ribonucleoprotein complex and flagellar assembly-related genes are downregulated. The results of this study indicate that both strain FKM10 and F. verticillioides have mutually inhibitory activities in a liquid environment. Comparative genome analysis of B. velezensis FKM10 reveals that the general features of their genomes are similar overall and contain the core genome for this species. The results of this study further reveal that B. velezensis can also serve as a basis for developing new biocontrol agents or microbial fertilizers.
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Affiliation(s)
- Chengqiang Wang
- Shandong Engineering Research Center of Plant-Microbial Restoration for Saline-Alkali Land, College of Life Sciences, Shandong Agricultural University, Tai'an, China
| | - Dongying Zhao
- Shandong Engineering Research Center of Plant-Microbial Restoration for Saline-Alkali Land, College of Life Sciences, Shandong Agricultural University, Tai'an, China
| | - Guozhen Qi
- Shandong Engineering Research Center of Plant-Microbial Restoration for Saline-Alkali Land, College of Life Sciences, Shandong Agricultural University, Tai'an, China
| | - Zhiquan Mao
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, China
| | - Xiuna Hu
- Shandong Engineering Research Center of Plant-Microbial Restoration for Saline-Alkali Land, College of Life Sciences, Shandong Agricultural University, Tai'an, China
| | - Binghai Du
- Shandong Engineering Research Center of Plant-Microbial Restoration for Saline-Alkali Land, College of Life Sciences, Shandong Agricultural University, Tai'an, China
| | - Kai Liu
- Shandong Engineering Research Center of Plant-Microbial Restoration for Saline-Alkali Land, College of Life Sciences, Shandong Agricultural University, Tai'an, China
| | - Yanqin Ding
- Shandong Engineering Research Center of Plant-Microbial Restoration for Saline-Alkali Land, College of Life Sciences, Shandong Agricultural University, Tai'an, China
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Fan B, Wang C, Ding X, Zhu B, Song X, Borriss R. AmyloWiki: an integrated database for Bacillus velezensis FZB42, the model strain for plant growth-promoting Bacilli. DATABASE-THE JOURNAL OF BIOLOGICAL DATABASES AND CURATION 2020; 2019:5520604. [PMID: 31219564 PMCID: PMC6585148 DOI: 10.1093/database/baz071] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 04/27/2019] [Accepted: 05/07/2019] [Indexed: 12/23/2022]
Abstract
Since its isolation 20 years ago, many studies have been devoted to Bacillus velezensis FZB42 (former name Bacillus amyloliquefaciens subsp. plantarum FZB42), which has been gradually accepted as a model organism for Gram-positive rhizobacteria. FZB42 is different from another widely studied bacterial strain, Bacillus subtilis 168, in its many features that are closely associated with plants. FZB42 represents a large group of Bacillus isolates that are beneficial to plants and of great importance in agriculture. In this work a database for FZB42 named 'AmyloWiki' is built to integrate all information of FZB42 available to date. The information includes the genomic, transcriptomic, proteomic, post-translational data as well as FZB42 unique genes, protein regulators, mutant availability, publications and etc. The website is built up with PHP and MySQL with a function of keyword searching, browsing, data-downloading and other functions.
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Affiliation(s)
- Ben Fan
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing 210037, China
| | - Cong Wang
- Department of Biomedical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
| | - Xiaolei Ding
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing 210037, China
| | - Bingyao Zhu
- Department of General Microbiology, Institute of Microbiology and Genetics, Georg-August University Göttingen, Grisebachstr. 8, D-37077 Göttingen, Germany
| | - Xiaofeng Song
- Department of Biomedical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
| | - Rainer Borriss
- Institut für Biologie, Humboldt Universität Berlin, 10115 Berlin, Germany, and Nord Reet UG, Marienstr. 27a, 17489 Greifswald, Germany
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Romano I, Ventorino V, Pepe O. Effectiveness of Plant Beneficial Microbes: Overview of the Methodological Approaches for the Assessment of Root Colonization and Persistence. FRONTIERS IN PLANT SCIENCE 2020; 11:6. [PMID: 32076431 PMCID: PMC7006617 DOI: 10.3389/fpls.2020.00006] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 01/06/2020] [Indexed: 05/22/2023]
Abstract
Issues concerning the use of harmful chemical fertilizers and pesticides that have large negative impacts on environmental and human health have generated increasing interest in the use of beneficial microorganisms for the development of sustainable agri-food systems. A successful microbial inoculant has to colonize the root system, establish a positive interaction and persist in the environment in competition with native microorganisms living in the soil through rhizocompetence traits. Currently, several approaches based on culture-dependent, microscopic and molecular methods have been developed to follow bioinoculants in the soil and plant surface over time. Although culture-dependent methods are commonly used to estimate the persistence of bioinoculants, it is difficult to differentiate inoculated organisms from native populations based on morphological characteristics. Therefore, these methods should be used complementary to culture-independent approaches. Microscopy-based techniques (bright-field, electron and fluorescence microscopy) allow to obtain a picture of microbial colonization outside and inside plant tissues also at high resolution, but it is not possible to always distinguish living cells from dead cells by direct observation as well as distinguish bioinoculants from indigenous microbial populations living in soils. In addition, the development of metagenomic techniques, including the use of DNA probes, PCR-based methods, next-generation sequencing, whole-genome sequencing and pangenome methods, provides a complementary approach useful to understand plant-soil-microbe interactions. However, to ensure good results in microbiological analysis, the first fundamental prerequisite is correct soil sampling and sample preparation for the different methodological approaches that will be assayed. Here, we provide an overview of the advantages and limitations of the currently used methods and new methodological approaches that could be developed to assess the presence, plant colonization and soil persistence of bioinoculants in the rhizosphere. We further discuss the possibility of integrating multidisciplinary approaches to examine the variations in microbial communities after inoculation and to track the inoculated microbial strains.
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Affiliation(s)
- Ida Romano
- Department of Agricultural Sciences, University of Naples Federico II, Naples, Italy
| | - Valeria Ventorino
- Department of Agricultural Sciences, University of Naples Federico II, Naples, Italy
- Task Force on Microbiome Studies, University of Naples Federico II, Naples, Italy
- *Correspondence: Valeria Ventorino,
| | - Olimpia Pepe
- Department of Agricultural Sciences, University of Naples Federico II, Naples, Italy
- Task Force on Microbiome Studies, University of Naples Federico II, Naples, Italy
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Eckshtain-Levi N, Harris SL, Roscios RQ, Shank EA. Bacterial Community Members Increase Bacillus subtilis Maintenance on the Roots of Arabidopsis thaliana. PHYTOBIOMES JOURNAL 2020; 4:303-313. [PMID: 34661038 PMCID: PMC8519414 DOI: 10.1094/pbiomes-02-20-0019-r] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Plant-growth-promoting bacteria (PGPB) are used to improve plant health and promote crop production. However, because some PGPB (including Bacillus subtilis) do not maintain substantial colonization on plant roots over time, it is unclear how effective PGPB are throughout the plant growing cycle. A better understanding of the dynamics of plant root community assembly is needed to develop and harness the potential of PGPB. Although B. subtilis is often a member of the root microbiome, it does not efficiently monoassociate with plant roots. We hypothesized that B. subtilis may require other primary colonizers to efficiently associate with plant roots. We utilized a previously designed hydroponic system to add bacteria to Arabidopsis thaliana roots and monitor their attachment over time. We inoculated seedlings with B. subtilis and individual bacterial isolates from the native A. thaliana root microbiome either alone or together. We then measured how the coinoculum affected the ability of B. subtilis to colonize and maintain on A. thaliana roots. We screened 96 fully genome-sequenced strains and identified five bacterial strains that were able to significantly improve the maintenance of B. subtilis. Three of these rhizobacteria also increased the maintenance of two strains of B. amyloliquefaciens commonly used in commercially available bioadditives. These results not only illustrate the utility of this model system to address questions about plant-microbe interactions and how other bacteria affect the ability of PGPB to maintain their relationships with plant roots but also may help inform future agricultural interventions to increase crop yields.
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Affiliation(s)
- Noam Eckshtain-Levi
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, U.S.A
| | - Susanna Leigh Harris
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, U.S.A
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, U.S.A
| | - Reizo Quilat Roscios
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, U.S.A
| | - Elizabeth Anne Shank
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, U.S.A
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, U.S.A
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, MA 01605, U.S.A
- Corresponding author: E. A. Shank;
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Deng S, Wipf HML, Pierroz G, Raab TK, Khanna R, Coleman-Derr D. A Plant Growth-Promoting Microbial Soil Amendment Dynamically Alters the Strawberry Root Bacterial Microbiome. Sci Rep 2019; 9:17677. [PMID: 31776356 PMCID: PMC6881409 DOI: 10.1038/s41598-019-53623-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 11/01/2019] [Indexed: 12/22/2022] Open
Abstract
Despite growing interest in utilizing microbial-based methods for improving crop growth, much work still remains in elucidating how beneficial plant-microbe associations are established, and what role soil amendments play in shaping these interactions. Here, we describe a set of experiments that test the effect of a commercially available soil amendment, VESTA, on the soil and strawberry (Fragaria x ananassa Monterey) root bacterial microbiome. The bacterial communities of the soil, rhizosphere, and root from amendment-treated and untreated fields were profiled at four time points across the strawberry growing season using 16S rRNA gene amplicon sequencing on the Illumina MiSeq platform. In all sample types, bacterial community composition and relative abundance were significantly altered with amendment application. Importantly, time point effects on composition are more pronounced in the root and rhizosphere, suggesting an interaction between plant development and treatment effect. Surprisingly, there was slight overlap between the taxa within the amendment and those enriched in plant and soil following treatment, suggesting that VESTA may act to rewire existing networks of organisms through an, as of yet, uncharacterized mechanism. These findings demonstrate that a commercial microbial soil amendment can impact the bacterial community structure of both roots and the surrounding environment.
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Affiliation(s)
- Siwen Deng
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA.,Plant Gene Expression Center, USDA-ARS, Albany, CA, USA
| | - Heidi M-L Wipf
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA.,Plant Gene Expression Center, USDA-ARS, Albany, CA, USA
| | - Grady Pierroz
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA.,Plant Gene Expression Center, USDA-ARS, Albany, CA, USA
| | - Ted K Raab
- Carnegie Institution for Science, Department of Plant Biology, Stanford, CA, USA
| | - Rajnish Khanna
- i-Cultiver, Inc., 404 Clipper Cove Way, San Francisco, CA, USA
| | - Devin Coleman-Derr
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA. .,Plant Gene Expression Center, USDA-ARS, Albany, CA, USA.
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Kandasamy S, Liu EYR, Patterson G, Saldias S, Ali S, Lazarovits G. Introducing key microbes from high productive soil transforms native soil microbial community of low productive soil. Microbiologyopen 2019; 8:e895. [PMID: 31250991 PMCID: PMC6813456 DOI: 10.1002/mbo3.895] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 05/27/2019] [Accepted: 06/03/2019] [Indexed: 11/11/2022] Open
Abstract
This study aimed to understand the changes in rhizosphere microbial structure and diversity of an average corn yielding field site soil with the introduced microbial candidates from a high‐yielding site. Soils used in this study were from two growers’ fields located in Dunnville, Ontario, Canada, where one of the farms has an exceptional high corn yield (G‐site soil; ca 20 tons/acre) and the other yields an average crop (H‐site soil; 12 tons/acre) (8 years of unpublished A & L data). In growth room experiments using wheat as the indicator crop, calcium alginate beads with microbes composed of Azospirillum lipoferum, Rhizobium leguminosarum, Burkholderia ambifaria, Burkholderia graminis, Burkholderia vietnamiensis, Pseudomonas lurida, Exiguobacterium acetylicum, Kosakonia cowanii, and Paenibacillus polymyxa was introduced into the soil at planting to the average‐yielding soil. These bacteria had been isolated from the high‐yielding farm soil. Among the nine microbial candidates tested, three (P. polymyxa, E. acetylicum and K. cowanii) significantly impacted the plant health and biometrics in addition to microbial richness and diversity, where the microbial profile became very similar to the high productive G‐site soil. One hundred and forty‐two bacterial terminal restriction fragments (TRFs) were involved in the community shift and 48 of them showed significant correlation to several interacting soil factors. This study indicates the potential of shifting microbial profiles of average‐yielding soils by introducing key candidates from highly productive soils to increase biological soil health.
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Affiliation(s)
- Saveetha Kandasamy
- A&L Biologicals, Agroecological Research Services Centre, London, Canada
| | - Elaine Yi Ran Liu
- A&L Biologicals, Agroecological Research Services Centre, London, Canada.,Department of Microbiology and Immunology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Canada
| | - Greg Patterson
- A&L Biologicals, Agroecological Research Services Centre, London, Canada
| | - Soledad Saldias
- A&L Biologicals, Agroecological Research Services Centre, London, Canada
| | - Shimaila Ali
- A&L Biologicals, Agroecological Research Services Centre, London, Canada
| | - George Lazarovits
- A&L Biologicals, Agroecological Research Services Centre, London, Canada
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Mahnert A, Haratani M, Schmuck M, Berg G. Enriching Beneficial Microbial Diversity of Indoor Plants and Their Surrounding Built Environment With Biostimulants. Front Microbiol 2018; 9:2985. [PMID: 30568641 PMCID: PMC6290261 DOI: 10.3389/fmicb.2018.02985] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 11/19/2018] [Indexed: 11/13/2022] Open
Abstract
Microbial diversity is suggested as the key for plant and human health. However, how microbial diversity can be enriched is largely unknown but of great interest for health issues. Biostimulants offer the way to directly augment our main living areas by the healthy microbiome of indoor plants. Here, we investigated shifts of the microbiome on leaves of spider plants (Chlorophytum comosum) and its surrounding abiotic surfaces in the built environment after irrigation with a vermicompost-based biostimulant for 12 weeks. The biostimulant could not only promote plant growth, but changed the composition of the microbiome and abundance of intact microbial cells on plant leaves and even stronger on abiotic surfaces in close vicinity under constant conditions of the microclimate. Biostimulant treatments stabilized microbial diversity and resulted in an increase of Bacteroidetes and a surprising transient emerge of new phyla, e.g., Verrucomicrobia, Acidobacteria, and Thaumarchaeota. The proportion of potentially beneficial microorganisms like Brevibacillus, Actinoallomurus, Paenibacillus, Sphaerisporangium increased relatively; microbial diversity was stabilized, and the built environment became more plant-like. Detected metabolites like indole-3-acetic acid in the biostimulant were potentially contributed by species of Pseudomonas. Overall, effects of the biostimulant on the composition of the microbiome could be predicted with an accuracy of 87%. This study shows the potential of biostimulants not only for the plant itself, but also for other living holobionts like humans in the surrounding environment.
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Affiliation(s)
- Alexander Mahnert
- Institute of Environmental Biotechnology, Graz University of Technology, Graz, Austria
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36
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Fan B, Wang C, Song X, Ding X, Wu L, Wu H, Gao X, Borriss R. Bacillus velezensis FZB42 in 2018: The Gram-Positive Model Strain for Plant Growth Promotion and Biocontrol. Front Microbiol 2018; 9:2491. [PMID: 30386322 PMCID: PMC6198173 DOI: 10.3389/fmicb.2018.02491] [Citation(s) in RCA: 165] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 09/28/2018] [Indexed: 12/31/2022] Open
Abstract
Bacillus velezensis FZB42, the model strain for Gram-positive plant-growth-promoting and biocontrol rhizobacteria, has been isolated in 1998 and sequenced in 2007. In order to celebrate these anniversaries, we summarize here the recent knowledge about FZB42. In last 20 years, more than 140 articles devoted to FZB42 have been published. At first, research was mainly focused on antimicrobial compounds, apparently responsible for biocontrol effects against plant pathogens, recent research is increasingly directed to expression of genes involved in bacteria–plant interaction, regulatory small RNAs (sRNAs), and on modification of enzymes involved in synthesis of antimicrobial compounds by processes such as acetylation and malonylation. Till now, 13 gene clusters involved in non-ribosomal and ribosomal synthesis of secondary metabolites with putative antimicrobial action have been identified within the genome of FZB42. These gene clusters cover around 10% of the whole genome. Antimicrobial compounds suppress not only growth of plant pathogenic bacteria and fungi, but could also stimulate induced systemic resistance (ISR) in plants. It has been found that besides secondary metabolites also volatile organic compounds are involved in the biocontrol effect exerted by FZB42 under biotic (plant pathogens) and abiotic stress conditions. In order to facilitate easy access to the genomic data, we have established an integrating data bank ‘AmyloWiki’ containing accumulated information about the genes present in FZB42, available mutant strains, and other aspects of FZB42 research, which is structured similar as the famous SubtiWiki data bank.
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Affiliation(s)
- Ben Fan
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, China
| | - Cong Wang
- Department of Biomedical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China
| | - Xiaofeng Song
- Department of Biomedical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China
| | - Xiaolei Ding
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, China
| | - Liming Wu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Huijun Wu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Xuewen Gao
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Rainer Borriss
- Institut für Biologie, Humboldt Universität Berlin, Berlin, Germany.,Nord Reet UG, Greifswald, Germany
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Gadhave KR, Gange AC. Interactions Involving Rhizobacteria and Foliar-Feeding Insects. ACTA ACUST UNITED AC 2018. [DOI: 10.1007/978-3-319-91614-9_6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/15/2023]
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38
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Exploitation of new endophytic bacteria and their ability to promote sugarcane growth and nitrogen nutrition. Antonie van Leeuwenhoek 2018; 112:283-295. [DOI: 10.1007/s10482-018-1157-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 08/28/2018] [Indexed: 10/28/2022]
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39
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Wu L, Wang J, Wu H, Chen J, Xiao Z, Qin X, Zhang Z, Lin W. Comparative Metagenomic Analysis of Rhizosphere Microbial Community Composition and Functional Potentials under Rehmannia glutinosa Consecutive Monoculture. Int J Mol Sci 2018; 19:ijms19082394. [PMID: 30110928 PMCID: PMC6121535 DOI: 10.3390/ijms19082394] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Revised: 08/08/2018] [Accepted: 08/08/2018] [Indexed: 11/16/2022] Open
Abstract
Consecutive monoculture of Rehmannia glutinosa, highly valued in traditional Chinese medicine, leads to a severe decline in both quality and yield. Rhizosphere microbiome was reported to be closely associated with the soil health and plant performance. In this study, comparative metagenomics was applied to investigate the shifts in rhizosphere microbial structures and functional potentials under consecutive monoculture. The results showed R. glutinosa monoculture significantly decreased the relative abundances of Pseudomonadaceae and Burkholderiaceae, but significantly increased the relative abundances of Sphingomonadaceae and Streptomycetaceae. Moreover, the abundances of genera Pseudomonas, Azotobacter, Burkholderia, and Lysobacter, among others, were significantly lower in two-year monocultured soil than in one-year cultured soil. For potentially harmful/indicator microorganisms, the percentages of reads categorized to defense mechanisms (i.e., ATP-binding cassette (ABC) transporters, efflux transporter, antibiotic resistance) and biological metabolism (i.e., lipid transport and metabolism, secondary metabolites biosynthesis, transport and catabolism, nucleotide transport and metabolism, transcription) were significantly higher in two-year monocultured soil than in one-year cultured soil, but the opposite was true for potentially beneficial microorganisms, which might disrupt the equilibrium between beneficial and harmful microbes. Collectively, our results provide important insights into the shifts in genomic diversity and functional potentials of rhizosphere microbiome in response to R. glutinosa consecutive monoculture.
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Affiliation(s)
- Linkun Wu
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
- Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Juanying Wang
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
- Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Hongmiao Wu
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
- Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Jun Chen
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
- Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Zhigang Xiao
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
- Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Xianjin Qin
- Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
- Key Laboratory of Crop Ecology and Molecular Physiology (Fujian Agriculture and Forestry University), Fujian Province University, Fuzhou 350002, China.
| | - Zhongyi Zhang
- Key Laboratory of Crop Ecology and Molecular Physiology (Fujian Agriculture and Forestry University), Fujian Province University, Fuzhou 350002, China.
- College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Wenxiong Lin
- Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
- Key Laboratory of Crop Ecology and Molecular Physiology (Fujian Agriculture and Forestry University), Fujian Province University, Fuzhou 350002, China.
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40
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Sekar J, Raju K, Duraisamy P, Ramalingam Vaiyapuri P. Potential of Finger Millet Indigenous Rhizobacterium Pseudomonas sp. MSSRFD41 in Blast Disease Management-Growth Promotion and Compatibility With the Resident Rhizomicrobiome. Front Microbiol 2018; 9:1029. [PMID: 29875748 PMCID: PMC5974220 DOI: 10.3389/fmicb.2018.01029] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 05/01/2018] [Indexed: 01/05/2023] Open
Abstract
Finger millet [Eleusine coracona (L). Gaertner] "Ragi" is a nutri-cereal with potential health benefits, and is utilized solely for human consumption in semi-arid regions of Asia and Africa. It is highly vulnerable to blast disease caused by Pyricularia grisea, resulting in 50-100% yield loss. Chemical fungicides are used for the management of blast disease, but with great safety concern. Alternatively, bioinoculants are widely used in promoting seedling efficiency, plant biomass, and disease control. Little is known about the impact of introduced indigenous beneficial rhizobacteria on the rhizosphere microbiota and growth promotion in finger millet. Strain MSSRFD41 exhibited a 22.35 mm zone of inhibition against P. grisea, produces antifungal metabolites, siderophores, hydrolytic enzymes, and IAA, and solubilizes phosphate. Environmental SEM analysis indicated the potential of MSSRFD41 to inhibit the growth of P. grisea by affecting cellular functions, which caused deformation in fungal hyphae. Bioprimed finger millet seeds exhibited significantly higher levels of germination, seedling vigor index, and enhanced shoot and root length compared to control seeds. Cross streaking and RAPD analysis showed that MSSRFD41 is compatible with different groups of rhizobacteria and survived in the rhizosphere. In addition, PLFA analysis revealed no significant difference in microbial biomass between the treated and control rhizosphere samples. Field trials showed that MSSRFD41 treatment significantly reduced blast infestation and enhanced plant growth compared to other treatments. A liquid formulated MSSRFD41 product maintained shelf life at an average of 108 CFU ml-1 over 150 days of storage at 25°C. Overall, results from this study demonstrated that Pseudomonas sp. MSSRFD41, an indigenous rhizobacterial strain, is an alternative, effective, and sustainable resource for the management of P. grisea infestation and growth promotion of finger millet.
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Affiliation(s)
- Jegan Sekar
- Microbiology Lab, M.S. Swaminathan Research Foundation, Chennai, India
| | - Kathiravan Raju
- Microbiology Lab, M.S. Swaminathan Research Foundation, Chennai, India
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41
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Ye M, Tang X, Yang R, Zhang H, Li F, Tao F, Li F, Wang Z. Characteristics and Application of a Novel Species of Bacillus: Bacillus velezensis. ACS Chem Biol 2018; 13:500-505. [PMID: 29309732 DOI: 10.1021/acschembio.7b00874] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Bacillus velezensis has been investigated and applied more and more widely recently because it can inhibit fungi and bacteria and become a potential biocontrol agent. In order to provide more clear and comprehensive understanding of B. velezensis for researchers, we collected the recent relevant articles systematically and reviewed the discovery and taxonomy, secondary metabolites, characteristics and application, gene function, and molecular research of B. velezensis. This review will give some direction to the research and application of this strain for the future.
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Affiliation(s)
- Miao Ye
- College of Life Science, Anhui Agricultural University, Anhui Hefei 230036, Peoples’ Republic of China
| | - Xiangfang Tang
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Ru Yang
- College of Life Science, Anhui Agricultural University, Anhui Hefei 230036, Peoples’ Republic of China
| | - Hongfu Zhang
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Fangshu Li
- College of Life Science, Anhui Agricultural University, Anhui Hefei 230036, Peoples’ Republic of China
| | - Fangzheng Tao
- College of Life Science, Anhui Agricultural University, Anhui Hefei 230036, Peoples’ Republic of China
| | - Fei Li
- College of Life Science, Anhui Agricultural University, Anhui Hefei 230036, Peoples’ Republic of China
| | - Zaigui Wang
- College of Life Science, Anhui Agricultural University, Anhui Hefei 230036, Peoples’ Republic of China
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42
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Schreiter S, Babin D, Smalla K, Grosch R. Rhizosphere Competence and Biocontrol Effect of Pseudomonas sp. RU47 Independent from Plant Species and Soil Type at the Field Scale. Front Microbiol 2018; 9:97. [PMID: 29449832 PMCID: PMC5799239 DOI: 10.3389/fmicb.2018.00097] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 01/16/2018] [Indexed: 12/20/2022] Open
Abstract
Biocontrol inoculants often show inconsistency in their efficacy at field scale and the reason for this remains often unclear. A high rhizosphere competence of inoculant strains is assumed to be a key factor for successful biocontrol effects as the biocontrol strain has to compete with the indigenous microbial community in the rhizosphere. It is known that many factors, among them plant species and soil type shape the rhizosphere microbial community composition. However, microbial community composition in the rhizosphere can also be influenced by the presence of a pathogen. We hypothesized that plant species, soil type, and a pathogen affect the rhizosphere competence of a biocontrol strain and its biocontrol effect against a soil-borne pathogen. To test the hypothesis, we used an experimental plot system with three soil types (diluvial sand, alluvial loam, loess loam) kept under similar agricultural management at the same field site for 12 years. We investigate the rhizosphere competence of Pseudomonas sp. RU47 in two plant species (potato and lettuce) and its biocontrol effect against Rhizoctonia diseases. The colonization density of a rifampicin resistant mutant of RU47 in the rhizosphere of both crops was evaluated by plate counts. Bacterial community compositions were analyzed by denaturing gradient gel electrophoresis (DGGE) of 16S rRNA gene fragments amplified from total community DNA. The inoculant RU47 was able to colonize the rhizosphere of both model crops in a sufficient density and to reduce disease severity of black scurf on potato and bottom rot on lettuce in all three soils. DGGE indicated that RU47 affected the bacterial community composition stronger in the rhizosphere of lettuce than in the potato rhizosphere. In contrast, the effect of the pathogen Rhizoctonia solani on the bacterial community was much stronger in the rhizosphere of potato than in the lettuce rhizosphere. A significant effect of RU47 on the Pseudomonas-specific gacA fingerprints of the rhizosphere was only observed in lettuce in alluvial soil. The soil type and plant species independent biocontrol effects of RU47 and its minor influence on the indigenous bacterial community composition might be important criteria for the registration and use of RU47 as biocontrol strain.
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Affiliation(s)
- Susanne Schreiter
- Institute for Epidemiology and Pathogen Diagnostics, Federal Research Centre for Cultivated Plants, Julius Kühn-Institut (JKI), Braunschweig, Germany
| | - Doreen Babin
- Institute for Epidemiology and Pathogen Diagnostics, Federal Research Centre for Cultivated Plants, Julius Kühn-Institut (JKI), Braunschweig, Germany
| | - Kornelia Smalla
- Institute for Epidemiology and Pathogen Diagnostics, Federal Research Centre for Cultivated Plants, Julius Kühn-Institut (JKI), Braunschweig, Germany
| | - Rita Grosch
- Department Plant-Microbe Systems, Leibniz Institute of Vegetable and Ornamental Crops, Großbeeren, Germany
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43
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Qin Y, Shang Q, Zhang Y, Li P, Chai Y. Bacillus amyloliquefaciens L-S60 Reforms the Rhizosphere Bacterial Community and Improves Growth Conditions in Cucumber Plug Seedling. Front Microbiol 2017; 8:2620. [PMID: 29312278 PMCID: PMC5744474 DOI: 10.3389/fmicb.2017.02620] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 12/15/2017] [Indexed: 12/05/2022] Open
Abstract
Vegetable plug seedling has become the most important way to produce vegetable seedlings in China. This seedling method can significantly improve the quality and yield of vegetables compared to conventional methods. In the process of plug seedling, chemical fertilizers or pesticides are often used to improve the yield of the seedlings albeit with increasing concerns. Meanwhile, little is known about the impact of beneficial bacteria on the rhizosphere microbiota and the growth conditions of vegetables during plug seedling. In this study, we applied a culture-independent next-generation sequencing-based approach and investigated the impact of a plant beneficial bacterium, Bacillus amyloliquefaciens L-S60, on the composition and dynamics of rhizosphere microbiota and the growth conditions of cucumbers during plug seedling. Our results showed that application of L-S60 significantly altered the structure of the bacterial community associated with the cucumber seedling; presence of beneficial rhizosphere species such as Bacillus, Rhodanobacter, Paenibacillus, Pseudomonas, Nonomuraea, and Agrobacterium was higher upon L-S60 treatment than in the control group. We also measured the impact of L-S60 application on the physiological properties of the cucumber seedlings as well as the availability of main mineral elements in the seedling at different time points during the plug seedling. Results from those measurements indicated that L-S60 application promoted growth conditions of cucumber seedlings and that more available mineral elements were detected in the cucumber seedlings from the L-S60 treated group than from the control group. The findings in this study provided evidence for the beneficial effects of plant growth-promoting rhizosphere bacteria on the bacterial community composition and growth conditions of the vegetables during plug seedling.
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Affiliation(s)
- Yuxuan Qin
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, Key Laboratory of Functional Dairy, China Agricultural University, Beijing, China.,Department of Biology, Northeastern University, Boston, MA, United States
| | - Qingmao Shang
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Ying Zhang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, Key Laboratory of Functional Dairy, China Agricultural University, Beijing, China
| | - Pinglan Li
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, Key Laboratory of Functional Dairy, China Agricultural University, Beijing, China
| | - Yunrong Chai
- Department of Biology, Northeastern University, Boston, MA, United States
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44
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Mayerhofer J, Eckard S, Hartmann M, Grabenweger G, Widmer F, Leuchtmann A, Enkerli J. Assessing effects of the entomopathogenic fungus Metarhizium brunneum on soil microbial communities in Agriotes spp. biological pest control. FEMS Microbiol Ecol 2017; 93:4111146. [PMID: 28961941 PMCID: PMC5812499 DOI: 10.1093/femsec/fix117] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 09/08/2017] [Indexed: 12/15/2022] Open
Abstract
The release of large quantities of microorganisms to soil for purposes such as pest control or plant growth promotion may affect the indigenous soil microbial communities. In our study, we investigated potential effects of Metarhizium brunneum ART2825 on soil fungi and prokaryota in bulk soil using high-throughput sequencing of ribosomal markers. Different formulations of this strain, and combinations of the fungus with garlic as efficacy-enhancing agent, were tested over 4 months in a pot and a field experiment carried out for biological control of Agriotes spp. in potatoes. A biocontrol effect was observed only in the pot experiment, i.e. the application of FCBK resulted in 77% efficacy. Colony counts combined with genotyping and marker sequence abundance confirmed the successful establishment of the applied strain. Only the formulated applied strain caused small shifts in fungal communities in the pot experiment. Treatment effects were in the same range as the effects caused by barley kernels, the carrier of the FCBK formulation and temporal effects. Garlic treatments and time affected prokaryotic communities. In the field experiment, only spatial differences affected fungal and prokaryotic communities. Our findings suggest that M. brunneum may not adversely affect soil microbial communities.
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Affiliation(s)
| | - Sonja Eckard
- Ecology of Noxious and Beneficial Organisms, Agroscope, CH-8046 Zurich, Switzerland
| | - Martin Hartmann
- Forest Soils and Biogeochemistry, Swiss Federal Research Institute WSL, CH-8903 Birmensdorf, Switzerland
| | - Giselher Grabenweger
- Ecology of Noxious and Beneficial Organisms, Agroscope, CH-8046 Zurich, Switzerland
| | - Franco Widmer
- Molecular Ecology, Agroscope, CH-8046 Zurich, Switzerland
| | - Adrian Leuchtmann
- Plant Ecological Genetics, Institute of Integrative Biology, ETH Zurich, CH-8092 Zurich, Switzerland
| | - Jürg Enkerli
- Molecular Ecology, Agroscope, CH-8046 Zurich, Switzerland
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45
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Finkel OM, Castrillo G, Herrera Paredes S, Salas González I, Dangl JL. Understanding and exploiting plant beneficial microbes. CURRENT OPINION IN PLANT BIOLOGY 2017; 38:155-163. [PMID: 28622659 PMCID: PMC5561662 DOI: 10.1016/j.pbi.2017.04.018] [Citation(s) in RCA: 275] [Impact Index Per Article: 39.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 04/25/2017] [Indexed: 05/18/2023]
Abstract
After a century of incremental research, technological advances, coupled with a need for sustainable crop yield increases, have reinvigorated the study of beneficial plant-microbe interactions with attention focused on how microbiomes alter plant phenotypes. We review recent advances in plant microbiome research, and describe potential applications for increasing crop productivity. The phylogenetic diversity of plant microbiomes is increasingly well characterized, and their functional diversity is becoming more accessible. Large culture collections are available for controlled experimentation, with more to come. Genetic resources are being brought to bear on questions of microbiome function. We expect that microbial amendments of varying complexities will expose rules governing beneficial plant-microbe interactions contributing to plant growth promotion and disease resistance, enabling more sustainable agriculture.
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Affiliation(s)
- Omri M Finkel
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599-3280, USA; Howard Hughes Medical Institute, University of North Carolina, Chapel Hill, NC 27599-3280, USA.
| | - Gabriel Castrillo
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599-3280, USA; Howard Hughes Medical Institute, University of North Carolina, Chapel Hill, NC 27599-3280, USA
| | - Sur Herrera Paredes
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599-3280, USA; Howard Hughes Medical Institute, University of North Carolina, Chapel Hill, NC 27599-3280, USA; Curriculum in Bioinformatics and Computational Biology, University of North Carolina, Chapel Hill, NC 27599-3280, USA
| | - Isai Salas González
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599-3280, USA; Howard Hughes Medical Institute, University of North Carolina, Chapel Hill, NC 27599-3280, USA; Curriculum in Bioinformatics and Computational Biology, University of North Carolina, Chapel Hill, NC 27599-3280, USA
| | - Jeffery L Dangl
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599-3280, USA; Howard Hughes Medical Institute, University of North Carolina, Chapel Hill, NC 27599-3280, USA; Curriculum in Bioinformatics and Computational Biology, University of North Carolina, Chapel Hill, NC 27599-3280, USA; Carolina Center for Genome Sciences, University of North Carolina, Chapel Hill, NC 27599-3280, USA; Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599-3280, USA; Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, NC 27599-3280, USA
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Qiao J, Yu X, Liang X, Liu Y, Borriss R, Liu Y. Addition of plant-growth-promoting Bacillus subtilis PTS-394 on tomato rhizosphere has no durable impact on composition of root microbiome. BMC Microbiol 2017; 17:131. [PMID: 28583081 PMCID: PMC5460418 DOI: 10.1186/s12866-017-1039-x] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 05/25/2017] [Indexed: 12/23/2022] Open
Abstract
Background Representatives of the genus Bacillus are increasingly used in agriculture to promote plant growth and to protect against plant pathogens. Unfortunately, hitherto the impact of Bacillus inoculants on the indigenous plant microbiota has been investigated exclusively for the species Bacillus amyloliquefaciens and was limited to prokaryotes, whilst eukaryotic member of this community, e.g. fungi, were not considered. Results The root-colonizing Bacillus subtilis PTS-394 supported growth of tomato plants and suppressed soil-borne diseases. Roche 454 pyrosequencing revealed that PTS-394 has only a transient impact on the microbiota community of the tomato rhizosphere. The impact on eukaryota could last up to 14 days, while that on bacterial communities lasted for 3 days only. Conclusions Ecological adaptation and microbial community-preserving capacity are important criteria when assessing suitability of bio-inoculants for commercial development. As shown here, B. subtilis PTS-394 is acting as an environmentally compatible plant protective agent without permanent effects on rhizosphere microbial community. Electronic supplementary material The online version of this article (doi:10.1186/s12866-017-1039-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Junqing Qiao
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu province, 210014, China
| | - Xiang Yu
- Suqian institute, Jiangsu Academy of Agricultural Sciences, Suqian, Jiangsu province, 223831, China
| | - Xuejie Liang
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu province, 210014, China
| | - Yongfeng Liu
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu province, 210014, China
| | - Rainer Borriss
- Institut für Agrarwissenschaften/Phytomedizin, Humboldt Universität zu Berlin, 14195, Berlin, Germany.,Nord Reet UG, 17489, Greifswald, Germany
| | - Youzhou Liu
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu province, 210014, China.
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47
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Sun W, Qian X, Gu J, Wang XJ, Li Y, Duan ML. Effects of inoculation with organic-phosphorus-mineralizing bacteria on soybean (Glycine max) growth and indigenous bacterial community diversity. Can J Microbiol 2017; 63:392-401. [PMID: 28177785 DOI: 10.1139/cjm-2016-0758] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
Three different organic-phosphorus-mineralizing bacteria (OPMB) strains were inoculated to soil planted with soybean (Glycine max), and their effects on soybean growth and indigenous bacterial community diversity were investigated. Inoculation with Pseudomonas fluorescens Z4-1 and Brevibacillus agri L7-1 increased organic phosphorus degradation by 22% and 30%, respectively, compared with the control at the mature stage. Strains P. fluorescens Z4-1 and B. agri L7-1 significantly improved the soil alkaline phosphatase activity, average well color development, and the soybean root activity. Terminal restriction fragment length polymorphism analysis demonstrated that P. fluorescens Z4-1 and B. agri L7-1 could persist in the soil at relative abundances of 2.0%-6.4% throughout soybean growth. Thus, P. fluorescens Z4-1 and B. agri L7-1 could potentially be used in organic-phosphorus-mineralizing biofertilizers. OPMB inoculation altered the genetic structure of the soil bacterial communities but had no apparent influence on the carbon source utilization profiles of the soil bacterial communities. Principal components analysis showed that the changes in the carbon source utilization profiles of bacterial community depended mainly on the plant growth stages rather than inoculation with OPMB. The results help to understand the evolution of the soil bacterial community after OPMB inoculation.
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Affiliation(s)
- Wei Sun
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Xun Qian
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Jie Gu
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Xiao-Juan Wang
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Yang Li
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Man-Li Duan
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
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48
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Pandin C, Le Coq D, Canette A, Aymerich S, Briandet R. Should the biofilm mode of life be taken into consideration for microbial biocontrol agents? Microb Biotechnol 2017; 10:719-734. [PMID: 28205337 PMCID: PMC5481536 DOI: 10.1111/1751-7915.12693] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 01/19/2017] [Accepted: 01/20/2017] [Indexed: 11/26/2022] Open
Abstract
Almost one‐third of crop yields are lost every year due to microbial alterations and diseases. The main control strategy to limit these losses is the use of an array of chemicals active against spoilage and unwanted pathogenic microorganisms. Their massive use has led to extensive environmental pollution, human poisoning and a variety of diseases. An emerging alternative to this chemical approach is the use of microbial biocontrol agents. Biopesticides have been used with success in several fields, but a better understanding of their mode of action is necessary to better control their activity and increase their use. Very few studies have considered that biofilms are the preferred mode of life of microorganisms in the target agricultural biotopes. Increasing evidence shows that the spatial organization of microbial communities on crop surfaces may drive important bioprotection mechanisms. The aim of this review is to summarize the evidence of biofilm formation by biocontrol agents on crops and discuss how this surface‐associated mode of life may influence their biology and interactions with other microorganisms and the host and, finally, their overall beneficial activity.
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Affiliation(s)
- Caroline Pandin
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Dominique Le Coq
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France.,Micalis Institute, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Alexis Canette
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Stéphane Aymerich
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Romain Briandet
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France
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Chen JN, Wei CW, Liu HC, Chen SY, Chen C, Juang YM, Lai CC, Yiang GT. Extracts containing CLPs of Bacillus amyloliquefaciens JN68 isolated from chicken intestines exert antimicrobial effects, particularly on methicillin-resistant Staphylococcus aureus and Listeria monocytogenes. Mol Med Rep 2016; 14:5155-5163. [PMID: 27840979 PMCID: PMC5355721 DOI: 10.3892/mmr.2016.5900] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Accepted: 10/11/2016] [Indexed: 11/06/2022] Open
Abstract
Bacillus amyloliquefaciens JN68, which has been discussed with regards to its antimicrobial activities, was successfully isolated from healthy chicken intestines in the present study. Using the spot-on-the-lawn antagonism method, the preliminary study indicated that a suspension culture of the B. amyloliquefaciens JN68 strain can inhibit the growth of Aspergillus niger and Penicillium pinophilum. Furthermore, the cyclic lipopeptides (CLPs) produced by the B. amyloliquefaciens JN68 strain were further purified through acid precipitation and Bond Elut®C18 chromatography, and their structures were identified using the liquid chromatography‑electrospray ionization‑mass spectrometry (MS)/MS method. Purified CLPs exerted broad spectrum antimicrobial activities on various pathogenic and foodborne bacteria and fungi, as determined using the agar well diffusion method. Listeria monocytogenes can induce listeriosis, which is associated with a high mortality rate. Methicillin‑resistant Staphylococcus aureus (MRSA) is a major pathogenic bacteria that causes nosocomial infections. Therefore, L. monocytogenes and MRSA are currently of great concern. The present study aimed to determine whether B. amyloliquefaciens JN68 extracts could inhibit L. monocytogenes and MRSA. The results indicated that extracts of B. amyloliquefaciens JN68 have CLP components, and can successfully inhibit the growth of L. monocytogenes and MRSA.
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Affiliation(s)
- Jen-Ni Chen
- Department of Nutrition, Master Program of Biomedical Nutrition, Hungkuang University, Taichung 433, Taiwan, R.O.C
| | - Chyou-Wei Wei
- Department of Nutrition, Master Program of Biomedical Nutrition, Hungkuang University, Taichung 433, Taiwan, R.O.C
| | - Hsiao-Chun Liu
- Department of Nutrition, Master Program of Biomedical Nutrition, Hungkuang University, Taichung 433, Taiwan, R.O.C
| | - Shu-Ying Chen
- Department of Nursing, Hungkuang University, Taichung 433, Taiwan, R.O.C
| | - Chinshuh Chen
- Department of Food Science and Biotechnology, National Chung Hsing University, Taichung 402, Taiwan, R.O.C
| | - Yu-Min Juang
- Institute of Molecular Biology, National Chung Hsing University, Taichung 402, Taiwan, R.O.C
| | - Chien-Chen Lai
- Institute of Molecular Biology, National Chung Hsing University, Taichung 402, Taiwan, R.O.C
| | - Giou-Teng Yiang
- Department of Emergency Medicine, School of Medicine, Tzu Chi University, Hualien 970, Taiwan, R.O.C
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50
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Parnell JJ, Berka R, Young HA, Sturino JM, Kang Y, Barnhart DM, DiLeo MV. From the Lab to the Farm: An Industrial Perspective of Plant Beneficial Microorganisms. FRONTIERS IN PLANT SCIENCE 2016; 7:1110. [PMID: 27540383 PMCID: PMC4973397 DOI: 10.3389/fpls.2016.01110] [Citation(s) in RCA: 143] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 07/12/2016] [Indexed: 05/18/2023]
Abstract
Any successful strategy aimed at enhancing crop productivity with microbial products ultimately relies on the ability to scale at regional to global levels. Microorganisms that show promise in the lab may lack key characteristics for widespread adoption in sustainable and productive agricultural systems. This paper provides an overview of critical considerations involved with taking a strain from discovery to the farmer's field. In addition, we review some of the most effective microbial products on the market today, explore the reasons for their success and outline some of the major challenges involved in industrial production and commercialization of beneficial strains for widespread agricultural application. General processes associated with commercializing viable microbial products are discussed in two broad categories, biofertility inoculants and biocontrol products. Specifically, we address what farmers desire in potential microbial products, how mode of action informs decisions on product applications, the influence of variation in laboratory and field study data, challenges with scaling for mass production, and the importance of consistent efficacy, product stability and quality. In order to make a significant impact on global sustainable agriculture, the implementation of plant beneficial microorganisms will require a more seamless transition between laboratory and farm application. Early attention to the challenges presented here will improve the likelihood of developing effective microbial products to improve crop yields, decrease disease severity, and help to feed an increasingly hungry planet.
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