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Khan AL. The phytomicrobiome: solving plant stress tolerance under climate change. Front Plant Sci 2023; 14:1219366. [PMID: 37746004 PMCID: PMC10513501 DOI: 10.3389/fpls.2023.1219366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 08/14/2023] [Indexed: 09/26/2023]
Abstract
With extraordinary global climate changes, increased episodes of extreme conditions result in continuous but complex interaction of environmental variables with plant life. Exploring natural phytomicrobiome species can provide a crucial resource of beneficial microbes that can improve plant growth and productivity through nutrient uptake, secondary metabolite production, and resistance against pathogenicity and abiotic stresses. The phytomicrobiome composition, diversity, and function strongly depend on the plant's genotype and climatic conditions. Currently, most studies have focused on elucidating microbial community abundance and diversity in the phytomicrobiome, covering bacterial communities. However, least is known about understanding the holistic phytomicrobiome composition and how they interact and function in stress conditions. This review identifies several gaps and essential questions that could enhance understanding of the complex interaction of microbiome, plant, and climate change. Utilizing eco-friendly approaches of naturally occurring synthetic microbial communities that enhance plant stress tolerance and leave fewer carbon-foot prints has been emphasized. However, understanding the mechanisms involved in stress signaling and responses by phytomicrobiome species under spatial and temporal climate changes is extremely important. Furthermore, the bacterial and fungal biome have been studied extensively, but the holistic interactome with archaea, viruses, oomycetes, protozoa, algae, and nematodes has seldom been studied. The inter-kingdom diversity, function, and potential role in improving environmental stress responses of plants are considerably important. In addition, much remains to be understood across organismal and ecosystem-level responses under dynamic and complex climate change conditions.
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Affiliation(s)
- Abdul Latif Khan
- Department of Engineering Technology, University of Houston, Houston, TX, United States
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2
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Chen W, Modi D, Picot A. Soil and Phytomicrobiome for Plant Disease Suppression and Management under Climate Change: A Review. Plants (Basel) 2023; 12:2736. [PMID: 37514350 PMCID: PMC10384710 DOI: 10.3390/plants12142736] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 07/17/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023]
Abstract
The phytomicrobiome plays a crucial role in soil and ecosystem health, encompassing both beneficial members providing critical ecosystem goods and services and pathogens threatening food safety and security. The potential benefits of harnessing the power of the phytomicrobiome for plant disease suppression and management are indisputable and of interest in agriculture but also in forestry and landscaping. Indeed, plant diseases can be mitigated by in situ manipulations of resident microorganisms through agronomic practices (such as minimum tillage, crop rotation, cover cropping, organic mulching, etc.) as well as by applying microbial inoculants. However, numerous challenges, such as the lack of standardized methods for microbiome analysis and the difficulty in translating research findings into practical applications are at stake. Moreover, climate change is affecting the distribution, abundance, and virulence of many plant pathogens, while also altering the phytomicrobiome functioning, further compounding disease management strategies. Here, we will first review literature demonstrating how agricultural practices have been found effective in promoting soil health and enhancing disease suppressiveness and mitigation through a shift of the phytomicrobiome. Challenges and barriers to the identification and use of the phytomicrobiome for plant disease management will then be discussed before focusing on the potential impacts of climate change on the phytomicrobiome functioning and disease outcome.
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Affiliation(s)
- Wen Chen
- Ottawa Research and Development Centre, Science and Technology Branch, Agriculture and Agri-Food Canada, Ottawa, ON K1A 0C6, Canada
- Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Dixi Modi
- Ottawa Research and Development Centre, Science and Technology Branch, Agriculture and Agri-Food Canada, Ottawa, ON K1A 0C6, Canada
| | - Adeline Picot
- Univ Brest, INRAE, Laboratoire Universitaire de Biodiversité et Écologie Microbienne, F-29280 Plouzané, France
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3
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Omotayo OP, Babalola OO. Fusarium verticillioides of maize plant: Potentials of propitious phytomicrobiome as biocontrol agents. Front Fungal Biol 2023; 4:1095765. [PMID: 37746120 PMCID: PMC10512380 DOI: 10.3389/ffunb.2023.1095765] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 01/26/2023] [Indexed: 09/26/2023]
Abstract
Disease outbreaks have been recorded due to exposure to Fusarium verticillioides and fumonisin, a mycotoxin produced by this fungus. F. verticillioides is a fungal pathogen of maize that causes infections, such as wilting and rotting, while contact with its fumonisin derivative manifests in the form of mild to severe illnesses in humans and animals. Maize infection by F. verticillioides causes loss or reduction in expected crop yield, thereby influencing households and nations' economies. While several efforts have been made to control the pathogenic fungus and its occurrence in the environment, it remains a challenge in agriculture, particularly in maize production. Several microorganisms which are plant-associated, especially those associated with the rhizosphere niche have been noted to possess antagonistic effects against F. verticillioides. They can inhibit the pathogen and tackle its debilitating effects on plants. Hence this study reviews the use of rhizosphere-associated biocontrol agents, such as Bacillus spp., Pseudomonas, Enterobacter, and Microbacterium oleivorans which forms part of the phytomicrobiome in other to prevent and control this toxicogenic fungus. These microorganisms were found to not only be effective in controlling its occurrence on maize plants but are environmentally safe and promote crop yield.
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Affiliation(s)
| | - Olubukola Oluranti Babalola
- Food Security and Safety Focus Area, Faculty of Natural and Agricultural Science, North-West University, Mmabatho, South Africa
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Khanna K, Kohli SK, Sharma N, Kour J, Devi K, Bhardwaj T, Dhiman S, Singh AD, Sharma N, Sharma A, Ohri P, Bhardwaj R, Ahmad P, Alam P, Albalawi TH. Phytomicrobiome communications: Novel implications for stress resistance in plants. Front Microbiol 2022; 13:912701. [PMID: 36274695 PMCID: PMC9583171 DOI: 10.3389/fmicb.2022.912701] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 07/15/2022] [Indexed: 11/13/2022] Open
Abstract
The agricultural sector is a foremost contributing factor in supplying food at the global scale. There are plethora of biotic as well as abiotic stressors that act as major constraints for the agricultural sector in terms of global food demand, quality, and security. Stresses affect rhizosphere and their communities, root growth, plant health, and productivity. They also alter numerous plant physiological and metabolic processes. Moreover, they impact transcriptomic and metabolomic changes, causing alteration in root exudates and affecting microbial communities. Since the evolution of hazardous pesticides and fertilizers, productivity has experienced elevation but at the cost of impeding soil fertility thereby causing environmental pollution. Therefore, it is crucial to develop sustainable and safe means for crop production. The emergence of various pieces of evidence depicting the alterations and abundance of microbes under stressed conditions proved to be beneficial and outstanding for maintaining plant legacy and stimulating their survival. Beneficial microbes offer a great potential for plant growth during stresses in an economical manner. Moreover, they promote plant growth with regulating phytohormones, nutrient acquisition, siderophore synthesis, and induce antioxidant system. Besides, acquired or induced systemic resistance also counteracts biotic stresses. The phytomicrobiome exploration is crucial to determine the growth-promoting traits, colonization, and protection of plants from adversities caused by stresses. Further, the intercommunications among rhizosphere through a direct/indirect manner facilitate growth and form complex network. The phytomicrobiome communications are essential for promoting sustainable agriculture where microbes act as ecological engineers for environment. In this review, we have reviewed our building knowledge about the role of microbes in plant defense and stress-mediated alterations within the phytomicrobiomes. We have depicted the defense biome concept that infers the design of phytomicrobiome communities and their fundamental knowledge about plant-microbe interactions for developing plant probiotics.
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Affiliation(s)
- Kanika Khanna
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, India
- Department of Microbiology, DAV University, Jalandhar, India
| | - Sukhmeen Kaur Kohli
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, India
| | - Nandni Sharma
- Department of Zoology, Guru Nanak Dev University, Amritsar, India
| | - Jaspreet Kour
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, India
| | - Kamini Devi
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, India
| | - Tamanna Bhardwaj
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, India
| | - Shalini Dhiman
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, India
| | - Arun Dev Singh
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, India
| | - Neerja Sharma
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, India
| | - Anket Sharma
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, China
| | - Puja Ohri
- Department of Zoology, Guru Nanak Dev University, Amritsar, India
| | - Renu Bhardwaj
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, India
| | - Parvaiz Ahmad
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia
- Department of Botany, S.P. College Srinagar, Jammu and Kashmir, India
| | - Pravej Alam
- Department of Biology, College of Science and Humanities, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia
| | - Thamer H. Albalawi
- Department of Biology, College of Science and Humanities, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia
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Malmstrom CM, Martin MD, Gagnevin L. Exploring the Emergence and Evolution of Plant Pathogenic Microbes Using Historical and Paleontological Sources. Annu Rev Phytopathol 2022; 60:187-209. [PMID: 35483672 DOI: 10.1146/annurev-phyto-021021-041830] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Biotechnological advances now permit broad exploration of past microbial communities preserved in diverse substrates. Despite biomolecular degradation, high-throughput sequencing of preserved materials can yield invaluable genomic and metagenomic data from the past. This line of research has expanded from its initial human- and animal-centric foci to include plant-associated microbes (viruses, archaea, bacteria, fungi, and oomycetes), for which historical, archaeological, and paleontological data illuminate past epidemics and evolutionary history. Genetic mechanisms underlying the acquisition of microbial pathogenicity, including hybridization, polyploidization, and horizontal gene transfer, can now be reconstructed, as can gene-for-gene coevolution with plant hosts. Epidemiological parameters, such as geographic origin and range expansion, can also be assessed. Building on published case studies with individual phytomicrobial taxa, the stage is now set for broader, community-wide studies of preserved plant microbiomes to strengthen mechanistic understanding of microbial interactions and plant disease emergence.
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Affiliation(s)
- Carolyn M Malmstrom
- Department of Plant Biology and Program in Ecology, Evolution, and Behavior, Michigan State University, East Lansing, Michigan, USA
| | - Michael D Martin
- Department of Natural History, University Museum, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Lionel Gagnevin
- Plant Health Institute of Montpellier, CIRAD, Montpellier, France;
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Lyu D, Msimbira LA, Nazari M, Antar M, Pagé A, Shah A, Monjezi N, Zajonc J, Tanney CAS, Backer R, Smith DL. The Coevolution of Plants and Microbes Underpins Sustainable Agriculture. Microorganisms 2021; 9:1036. [PMID: 34065848 DOI: 10.3390/microorganisms9051036] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 05/01/2021] [Accepted: 05/07/2021] [Indexed: 12/20/2022] Open
Abstract
Terrestrial plants evolution occurred in the presence of microbes, the phytomicrobiome. The rhizosphere microbial community is the most abundant and diverse subset of the phytomicrobiome and can include both beneficial and parasitic/pathogenic microbes. Prokaryotes of the phytomicrobiome have evolved relationships with plants that range from non-dependent interactions to dependent endosymbionts. The most extreme endosymbiotic examples are the chloroplasts and mitochondria, which have become organelles and integral parts of the plant, leading to some similarity in DNA sequence between plant tissues and cyanobacteria, the prokaryotic symbiont of ancestral plants. Microbes were associated with the precursors of land plants, green algae, and helped algae transition from aquatic to terrestrial environments. In the terrestrial setting the phytomicrobiome contributes to plant growth and development by (1) establishing symbiotic relationships between plant growth-promoting microbes, including rhizobacteria and mycorrhizal fungi, (2) conferring biotic stress resistance by producing antibiotic compounds, and (3) secreting microbe-to-plant signal compounds, such as phytohormones or their analogues, that regulate aspects of plant physiology, including stress resistance. As plants have evolved, they recruited microbes to assist in the adaptation to available growing environments. Microbes serve themselves by promoting plant growth, which in turn provides microbes with nutrition (root exudates, a source of reduced carbon) and a desirable habitat (the rhizosphere or within plant tissues). The outcome of this coevolution is the diverse and metabolically rich microbial community that now exists in the rhizosphere of terrestrial plants. The holobiont, the unit made up of the phytomicrobiome and the plant host, results from this wide range of coevolved relationships. We are just beginning to appreciate the many ways in which this complex and subtle coevolution acts in agricultural systems.
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Lyu D, Zajonc J, Pagé A, Tanney CAS, Shah A, Monjezi N, Msimbira LA, Antar M, Nazari M, Backer R, Smith DL. Plant Holobiont Theory: The Phytomicrobiome Plays a Central Role in Evolution and Success. Microorganisms 2021; 9:675. [PMID: 33805166 PMCID: PMC8064057 DOI: 10.3390/microorganisms9040675] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 03/20/2021] [Accepted: 03/23/2021] [Indexed: 12/15/2022] Open
Abstract
Under natural conditions, plants are always associated with a well-orchestrated community of microbes-the phytomicrobiome. The nature and degree of microbial effect on the plant host can be positive, neutral, or negative, and depends largely on the environment. The phytomicrobiome is integral for plant growth and function; microbes play a key role in plant nutrient acquisition, biotic and abiotic stress management, physiology regulation through microbe-to-plant signals, and growth regulation via the production of phytohormones. Relationships between the plant and phytomicrobiome members vary in intimacy, ranging from casual associations between roots and the rhizosphere microbial community, to endophytes that live between plant cells, to the endosymbiosis of microbes by the plant cell resulting in mitochondria and chloroplasts. If we consider these key organelles to also be members of the phytomicrobiome, how do we distinguish between the two? If we accept the mitochondria and chloroplasts as both members of the phytomicrobiome and the plant (entrained microbes), the influence of microbes on the evolution of plants becomes so profound that without microbes, the concept of the "plant" is not viable. This paper argues that the holobiont concept should take greater precedence in the plant sciences when referring to a host and its associated microbial community. The inclusivity of this concept accounts for the ambiguous nature of the entrained microbes and the wide range of functions played by the phytomicrobiome in plant holobiont homeostasis.
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Affiliation(s)
- Dongmei Lyu
- Department of Plant Science, Macdonald Campus, McGill University, Montréal, QC H9X 3V9, Canada; (D.L.); (J.Z.); (A.P.); (C.A.S.T.); (A.S.); (N.M.); (L.A.M.); (M.A.); (M.N.); (R.B.)
| | - Jonathan Zajonc
- Department of Plant Science, Macdonald Campus, McGill University, Montréal, QC H9X 3V9, Canada; (D.L.); (J.Z.); (A.P.); (C.A.S.T.); (A.S.); (N.M.); (L.A.M.); (M.A.); (M.N.); (R.B.)
| | - Antoine Pagé
- Department of Plant Science, Macdonald Campus, McGill University, Montréal, QC H9X 3V9, Canada; (D.L.); (J.Z.); (A.P.); (C.A.S.T.); (A.S.); (N.M.); (L.A.M.); (M.A.); (M.N.); (R.B.)
- National Research Council Canada, Aquatic and Crop Resource Development (ACRD), Montréal, QC H4P 2R2, Canada
| | - Cailun A. S. Tanney
- Department of Plant Science, Macdonald Campus, McGill University, Montréal, QC H9X 3V9, Canada; (D.L.); (J.Z.); (A.P.); (C.A.S.T.); (A.S.); (N.M.); (L.A.M.); (M.A.); (M.N.); (R.B.)
| | - Ateeq Shah
- Department of Plant Science, Macdonald Campus, McGill University, Montréal, QC H9X 3V9, Canada; (D.L.); (J.Z.); (A.P.); (C.A.S.T.); (A.S.); (N.M.); (L.A.M.); (M.A.); (M.N.); (R.B.)
| | - Nadia Monjezi
- Department of Plant Science, Macdonald Campus, McGill University, Montréal, QC H9X 3V9, Canada; (D.L.); (J.Z.); (A.P.); (C.A.S.T.); (A.S.); (N.M.); (L.A.M.); (M.A.); (M.N.); (R.B.)
| | - Levini A. Msimbira
- Department of Plant Science, Macdonald Campus, McGill University, Montréal, QC H9X 3V9, Canada; (D.L.); (J.Z.); (A.P.); (C.A.S.T.); (A.S.); (N.M.); (L.A.M.); (M.A.); (M.N.); (R.B.)
| | - Mohammed Antar
- Department of Plant Science, Macdonald Campus, McGill University, Montréal, QC H9X 3V9, Canada; (D.L.); (J.Z.); (A.P.); (C.A.S.T.); (A.S.); (N.M.); (L.A.M.); (M.A.); (M.N.); (R.B.)
| | - Mahtab Nazari
- Department of Plant Science, Macdonald Campus, McGill University, Montréal, QC H9X 3V9, Canada; (D.L.); (J.Z.); (A.P.); (C.A.S.T.); (A.S.); (N.M.); (L.A.M.); (M.A.); (M.N.); (R.B.)
| | - Rachel Backer
- Department of Plant Science, Macdonald Campus, McGill University, Montréal, QC H9X 3V9, Canada; (D.L.); (J.Z.); (A.P.); (C.A.S.T.); (A.S.); (N.M.); (L.A.M.); (M.A.); (M.N.); (R.B.)
| | - Donald L. Smith
- Department of Plant Science, Macdonald Campus, McGill University, Montréal, QC H9X 3V9, Canada; (D.L.); (J.Z.); (A.P.); (C.A.S.T.); (A.S.); (N.M.); (L.A.M.); (M.A.); (M.N.); (R.B.)
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Jiao X, Takishita Y, Zhou G, Smith DL. Plant Associated Rhizobacteria for Biocontrol and Plant Growth Enhancement. Front Plant Sci 2021; 12:634796. [PMID: 33815442 PMCID: PMC8009966 DOI: 10.3389/fpls.2021.634796] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 02/23/2021] [Indexed: 05/20/2023]
Abstract
Crop disease remains a major problem to global food production. Excess use of pesticides through chemical disease control measures is a serious problem for sustainable agriculture as we struggle for higher crop productivity. The use of plant growth promoting rhizobacteria (PGPR) is a proven environment friendly way of controlling plant disease and increasing crop yield. PGPR suppress diseases by directly synthesizing pathogen-antagonizing compounds, as well as by triggering plant immune responses. It is possible to identify and develop PGPR that both suppress plant disease and more directly stimulate plant growth, bringing dual benefit. A number of PGPR have been registered for commercial use under greenhouse and field conditions and a large number of strains have been identified and proved as effective biocontrol agents (BCAs) under environmentally controlled conditions. However, there are still a number of challenges before registration, large-scale application, and adoption of PGPR for the pest and disease management. Successful BCAs provide strong theoretical and practical support for application of PGPR in greenhouse production, which ensures the feasibility and efficacy of PGPR for commercial horticulture production. This could be pave the way for widespread use of BCAs in agriculture, including under field conditions, to assist with both disease management and climate change conditions.
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Affiliation(s)
- Xiurong Jiao
- Institute of Agricultural Science and Technology Development of Yangzhou University, Yangzhou, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, China
- Department of Plant Science, Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, QC, Canada
| | - Yoko Takishita
- Department of Plant Science, Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, QC, Canada
| | - Guisheng Zhou
- Institute of Agricultural Science and Technology Development of Yangzhou University, Yangzhou, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, China
| | - Donald L. Smith
- Department of Plant Science, Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, QC, Canada
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Naamala J, Smith DL. Microbial Derived Compounds, a Step Toward Enhancing Microbial Inoculants Technology for Sustainable Agriculture. Front Microbiol 2021; 12:634807. [PMID: 33679668 PMCID: PMC7930237 DOI: 10.3389/fmicb.2021.634807] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Accepted: 01/29/2021] [Indexed: 11/16/2022] Open
Abstract
Sustainable agriculture remains a focus for many researchers, in an effort to minimize environmental degradation and climate change. The use of plant growth promoting microorganisms (PGPM) is a hopeful approach for enhancing plant growth and yield. However, the technology faces a number of challenges, especially inconsistencies in the field. The discovery, that microbial derived compounds can independently enhance plant growth, could be a step toward minimizing shortfalls related to PGPM technology. This has led many researchers to engage in research activities involving such compounds. So far, the findings are promising as compounds have been reported to enhance plant growth under stressed and non-stressed conditions in a wide range of plant species. This review compiles current knowledge on microbial derived compounds, taking a reader through a summarized protocol of their isolation and identification, their relevance in present agricultural trends, current use and limitations, with a view to giving the reader a picture of where the technology has come from, and an insight into where it could head, with some suggestions regarding the probable best ways forward.
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Affiliation(s)
- Judith Naamala
- Smith Laboratory, Department of Plant Science, McGill University, Quebec, QC, Canada
| | - Donald L Smith
- Smith Laboratory, Department of Plant Science, McGill University, Quebec, QC, Canada
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Bolaji AJ, Wan JC, Manchur CL, Lawley Y, de Kievit TR, Fernando WGD, Belmonte MF. Microbial Community Dynamics of Soybean ( Glycine max) Is Affected by Cropping Sequence. Front Microbiol 2021; 12:632280. [PMID: 33643263 PMCID: PMC7904696 DOI: 10.3389/fmicb.2021.632280] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Accepted: 01/22/2021] [Indexed: 12/28/2022] Open
Abstract
The microbial composition of the rhizosphere soil could be an important determinant of crop yield, pathogen resistance, and other beneficial attributes in plants. However, little is known about the impact of cropping sequences on microbial community dynamics, especially in economically important species like soybean. Using 2-year crop sequences of corn-soybean, canola-soybean, and soybean-soybean, we investigated how crops from the previous growing season influenced the structure of the microbiome in both the bulk soil and soybean rhizosphere. A combination of marker-based Illumina sequencing and bioinformatics analyses was used to show that bacterial species richness and evenness in the soybean rhizosphere soil were similar following canola and soybean compared to a previous corn sequence. However, fungal species richness and evenness remained unaffected by crop sequence. In addition, bacterial and fungal species diversity in both the bulk and soybean rhizosphere soil were not influenced by crop sequence. Lastly, the corn-soybean sequence significantly differed in the relative abundance of certain bacterial and fungal classes in both the soybean rhizosphere and bulk soil. While canola-soybean and a continuous soybean sequence did not, suggesting that a preceding corn sequence may reduce the occurrence of overall bacterial and fungal community members. For the present study, crop sequence impacts bacterial diversity and richness in both the bulk soil and soybean rhizosphere soil whereas fungal diversity and richness are resilient to crop sequence practices. Together, these findings could help drive decision making for annual crop and soil management practices.
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Affiliation(s)
- Ayooluwa J Bolaji
- Department of Biological Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Joey C Wan
- Department of Biological Sciences, University of Manitoba, Winnipeg, MB, Canada
| | | | - Yvonne Lawley
- Department of Plant Science, University of Manitoba, Winnipeg, MB, Canada
| | - Teresa R de Kievit
- Department of Microbiology, University of Manitoba, Winnipeg, MB, Canada
| | | | - Mark F Belmonte
- Department of Biological Sciences, University of Manitoba, Winnipeg, MB, Canada
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Yang F, Zhang J, Zhang H, Ji G, Zeng L, Li Y, Yu C, Fernando WGD, Chen W. Bacterial Blight Induced Shifts in Endophytic Microbiome of Rice Leaves and the Enrichment of Specific Bacterial Strains With Pathogen Antagonism. Front Plant Sci 2020; 11:963. [PMID: 32793250 PMCID: PMC7390967 DOI: 10.3389/fpls.2020.00963] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 06/11/2020] [Indexed: 05/25/2023]
Abstract
The endophytic microbiome plays an important role in plant health and pathogenesis. However, little is known about its relationship with bacterial blight (BB) of rice caused by Xanthomonas oryzae pv. oryzae (Xoo). The current study compared the community compositional structure of the endophytic microbiota in healthy and BB symptomatic leaves of rice through a metabarcoding approach, which revealed BB induced a decrease in the alpha-diversity of the fungal communities and an increase in the bacterial communities. BB-diseased rice leaves were enriched with saprophytic fungi that are capable of decomposing plant cell walls (e.g. Khuskia spp. and Leptosphaerulina spp.), while healthy rice leaves were found to be significantly more abundant with plant pathogens or mycotoxin-producing fungi (e.g. Fusarium, Magnaporthe, and Aspergillus). The endophytic bacterial communities of BB-diseased leaves were significantly enriched with Pantoea, Pseudomonas, and Curtobacterium, strains. Pantoea sp. isolates from BB leaves are identified as promising candidates for the biocontrol of BB for their ability to inhibit in vitro growth of Xoo, suppress the development of rice BB disease, and possess multiple PGP characteristics. Our study revealed BB-induced complexed changes in the endophytic fungal and bacterial communities of rice leaves and demonstrated that BB-associated enrichment of some endophytic bacterial taxa, e.g. Pantoea sp. isolates, may play important roles in suppressing the development of BB disease in rice.
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Affiliation(s)
- Fenghuan Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jie Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Huaying Zhang
- Ottawa Research & Development Centre, Science & Technology Branch, Agriculture and Agri-Food Canada, Ottawa, ON, Canada
| | - Guanghai Ji
- College of Plant Protection, Yunnan Agricultural University, Kunming, China
| | - Liexian Zeng
- Plant Protection Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Yan Li
- Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing, China
| | - Chao Yu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | | | - Wen Chen
- Ottawa Research & Development Centre, Science & Technology Branch, Agriculture and Agri-Food Canada, Ottawa, ON, Canada
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Nazari M, Smith DL. A PGPR-Produced Bacteriocin for Sustainable Agriculture: A Review of Thuricin 17 Characteristics and Applications. Front Plant Sci 2020; 11:916. [PMID: 32733506 PMCID: PMC7358586 DOI: 10.3389/fpls.2020.00916] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 06/04/2020] [Indexed: 05/08/2023]
Abstract
A wide range of prokaryotes produce and excrete bacteriocins (proteins with antimicrobial activity) to reduce competition from closely related strains. Application of bacteriocins is of great importance in food industries, while little research has been focused on the agricultural potential of bacteriocins. A number of bacteriocin producing bacteria are members of the phytomicrobiome, and some strains are plant growth promoting rhizobacteria (PGPR). Thuricin 17 is a single small peptide with a molecular weight of 3.162 kDa, a subclass IId bacteriocin produced by Bacillus thuringiensis NEB17, isolated from soybean nodules. It is either cidal or static to a wide range of prokaryotes. In this way, it removes key competition from the niche space of the producer organism. B. thuringiensis NEB17 was isolated from soybean root nodules, and thus is a member of the phytomicrobiome. Interestingly, thuricin 17 is not active against a wide range of rhizobial strains involved in symbiotic nitrogen fixation with legumes or against other PGPR. In addition, it stimulates plant growth, particularly in the presence of abiotic stresses. The stresses it assists with include key ones associated with climate change (drought, high temperature, and soil salinity). Hence, in the presence of stress, it increases the size of the overall niche space, within plant roots, for B. thuringiensis NEB17. Through its anti-microbial activity, it could also enhance plant growth via control of specific plant pathogens. None of the isolated bacteriocins have been examined as broadly as thuricin 17 on plant growth promotion. Thus, this review focuses on the effect of thuricin 17 as a microbe to plant signal that assists crop plants in managing stress and making agricultural systems more climate change resilient.
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Uroz S, Courty PE, Oger P. Plant Symbionts Are Engineers of the Plant-Associated Microbiome. Trends Plant Sci 2019; 24:905-916. [PMID: 31288964 DOI: 10.1016/j.tplants.2019.06.008] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 06/03/2019] [Accepted: 06/07/2019] [Indexed: 05/09/2023]
Abstract
Plants interact throughout their lives with environmental microorganisms. These interactions determine plant development, nutrition, and fitness in a dynamic and stressful environment, forming the basis for the holobiont concept in which plants and plant-associated microbes are not considered as independent entities but as a single evolutionary unit. A primary open question concerns whether holobiont structure is shaped by its microbial members or solely by the plant. Current knowledge of plant-microbe interactions argues that the establishment of symbiosis directly and indirectly conditions the plant-associated microbiome. We propose to define the impact of the symbiont on the plant microbiome as the 'symbiosis cascade effect', in which the symbionts and their plant host jointly shape the plant microbiome.
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Affiliation(s)
- Stephane Uroz
- Institut National de la Recherche Agronomique (INRA) Unité Mixte de Recherche (UMR) 1136, Interactions Arbres-Microorganismes, F-54280, Champenoux, France; Université de Lorraine, UMR 1136, Interactions Arbres-Microorganismes, F-54500 Vandoeuvre-lès-, Nancy, France; INRA Unité de Recherche (UR) 1138, Biogéochimie des Écosystèmes Forestiers, F-54280, Champenoux, France.
| | - Pierre Emmanuel Courty
- Agroécologie, Institut National de la Recherche, Agronomique (INRA), AgroSup Dijon, Centre, National de la Recherche Scientifique (CNRS), Université de Bourgogne, INRA, Université de Bourgogne Franche-Comté, F-21000 Dijon, France
| | - Phil Oger
- Université de Lyon, Institut National des Sciences Appliquées (INSA) de Lyon, CNRS UMR, 5240, Villeurbanne, France
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Backer R, Rokem JS, Ilangumaran G, Lamont J, Praslickova D, Ricci E, Subramanian S, Smith DL. Plant Growth-Promoting Rhizobacteria: Context, Mechanisms of Action, and Roadmap to Commercialization of Biostimulants for Sustainable Agriculture. Front Plant Sci 2018; 9:1473. [PMID: 30405652 PMCID: PMC6206271 DOI: 10.3389/fpls.2018.01473] [Citation(s) in RCA: 543] [Impact Index Per Article: 90.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 09/20/2018] [Indexed: 05/02/2023]
Abstract
Microbes of the phytomicrobiome are associated with every plant tissue and, in combination with the plant form the holobiont. Plants regulate the composition and activity of their associated bacterial community carefully. These microbes provide a wide range of services and benefits to the plant; in return, the plant provides the microbial community with reduced carbon and other metabolites. Soils are generally a moist environment, rich in reduced carbon which supports extensive soil microbial communities. The rhizomicrobiome is of great importance to agriculture owing to the rich diversity of root exudates and plant cell debris that attract diverse and unique patterns of microbial colonization. Microbes of the rhizomicrobiome play key roles in nutrient acquisition and assimilation, improved soil texture, secreting, and modulating extracellular molecules such as hormones, secondary metabolites, antibiotics, and various signal compounds, all leading to enhancement of plant growth. The microbes and compounds they secrete constitute valuable biostimulants and play pivotal roles in modulating plant stress responses. Research has demonstrated that inoculating plants with plant-growth promoting rhizobacteria (PGPR) or treating plants with microbe-to-plant signal compounds can be an effective strategy to stimulate crop growth. Furthermore, these strategies can improve crop tolerance for the abiotic stresses (e.g., drought, heat, and salinity) likely to become more frequent as climate change conditions continue to develop. This discovery has resulted in multifunctional PGPR-based formulations for commercial agriculture, to minimize the use of synthetic fertilizers and agrochemicals. This review is an update about the role of PGPR in agriculture, from their collection to commercialization as low-cost commercial agricultural inputs. First, we introduce the concept and role of the phytomicrobiome and the agricultural context underlying food security in the 21st century. Next, mechanisms of plant growth promotion by PGPR are discussed, including signal exchange between plant roots and PGPR and how these relationships modulate plant abiotic stress responses via induced systemic resistance. On the application side, strategies are discussed to improve rhizosphere colonization by PGPR inoculants. The final sections of the paper describe the applications of PGPR in 21st century agriculture and the roadmap to commercialization of a PGPR-based technology.
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Affiliation(s)
- Rachel Backer
- Department of Plant Science, McGill University, Montreal, QC, Canada
| | - J. Stefan Rokem
- School of Medicine, Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, The Hebrew University of Jerusalem, Jerusalem, Israel
| | | | - John Lamont
- Department of Plant Science, McGill University, Montreal, QC, Canada
| | - Dana Praslickova
- Department of Plant Science, McGill University, Montreal, QC, Canada
| | - Emily Ricci
- Department of Plant Science, McGill University, Montreal, QC, Canada
| | | | - Donald L. Smith
- Department of Plant Science, McGill University, Montreal, QC, Canada
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Affiliation(s)
- Donald L. Smith
- Plant Science Department, McGill UniversitySte. Anne de Bellevue, QC, Canada
- *Correspondence: Donald L. Smith
| | - Valérie Gravel
- Plant Science Department, McGill UniversitySte. Anne de Bellevue, QC, Canada
| | - Etienne Yergeau
- Centre INRS-Institut Armand-Frappier, Institut National de la Recherche Scientifique, Université du QuébecLaval, QC, Canada
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Smith DL, Subramanian S, Lamont JR, Bywater-Ekegärd M. Signaling in the phytomicrobiome: breadth and potential. Front Plant Sci 2015; 6:709. [PMID: 26442023 PMCID: PMC4563166 DOI: 10.3389/fpls.2015.00709] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 08/24/2015] [Indexed: 05/18/2023]
Abstract
Higher plants have evolved intimate, complex, subtle, and relatively constant relationships with a suite of microbes, the phytomicrobiome. Over the last few decades we have learned that plants and microbes can use molecular signals to communicate. This is well-established for the legume-rhizobia nitrogen-fixing symbiosis, and reasonably elucidated for mycorrhizal associations. Bacteria within the phytomircobiome communicate among themselves through quorum sensing and other mechanisms. Plants also detect materials produced by potential pathogens and activate pathogen-response systems. This intercommunication dictates aspects of plant development, architecture, and productivity. Understanding this signaling via biochemical, genomics, proteomics, and metabolomic studies has added valuable knowledge regarding development of effective, low-cost, eco-friendly crop inputs that reduce fossil fuel intense inputs. This knowledge underpins phytomicrobiome engineering: manipulating the beneficial consortia that manufacture signals/products that improve the ability of the plant-phytomicrobiome community to deal with various soil and climatic conditions, leading to enhanced overall crop plant productivity.
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Affiliation(s)
- Donald L. Smith
- Plant Science Department, McGill University/Macdonald Campus, Sainte-Anne-de-Bellevue, QCCanada
| | | | - John R. Lamont
- Plant Science Department, McGill University/Macdonald Campus, Sainte-Anne-de-Bellevue, QCCanada
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Smith DL, Praslickova D, Ilangumaran G. Inter-organismal signaling and management of the phytomicrobiome. Front Plant Sci 2015; 6:722. [PMID: 26442036 PMCID: PMC4568390 DOI: 10.3389/fpls.2015.00722] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 08/28/2015] [Indexed: 05/18/2023]
Abstract
The organisms of the phytomicrobiome use signal compounds to regulate aspects of each other's behavior. Legumes use signals (flavonoids) to regulate rhizobial nod gene expression during establishment of the legume-rhizobia N2-fixation symbiosis. Lipochitooligosaccharides (LCOs) produced by rhizobia act as return signals to the host plant and are recognized by specific lysine motif receptor like kinases, which triggers a signal cascade leading to nodulation of legume roots. LCOs also enhance plant growth, particularly when plants are stressed. Chitooligosaccharides activate plant immune responses, providing enhanced resistance against diseases. Co-inoculation of rhizobia with other plant growth promoting rhizobacteria (PGPR) can improve nodulation and crop growth. PGPR also alleviate plant stress by secreting signal compounds including phytohormones and antibiotics. Thuricin 17, a small bacteriocin produced by a phytomicrobiome member promotes plant growth. Lumichrome synthesized by soil rhizobacteria function as stress-sensing cues. Inter-organismal signaling can be used to manage/engineer the phytomicrobiome to enhance crop productivity, particularly in the face of stress. Stressful conditions are likely to become more frequent and more severe because of climate change.
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Affiliation(s)
- Donald L. Smith
- *Correspondence: Donald L. Smith, Plant Science Department, McGill University/Macdonald Campus, 21,111 Lakeshore Road, Sainte Anne de Bellevue, QC H9X 3V9, Canada,
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