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Kumar A, Solanki MK, Wang Z, Solanki AC, Singh VK, Divvela PK. Revealing the seed microbiome: Navigating sequencing tools, microbial assembly, and functions to amplify plant fitness. Microbiol Res 2024; 279:127549. [PMID: 38056172 DOI: 10.1016/j.micres.2023.127549] [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: 09/03/2023] [Revised: 11/10/2023] [Accepted: 11/12/2023] [Indexed: 12/08/2023]
Abstract
Microbial communities within seeds play a vital role in transmitting themselves to the next generation of plants. These microorganisms significantly impact seed vigor and early seedling growth, for successful crop establishment. Previous studies reported on seed-associated microbial communities and their influence on processes like dormancy release, germination, and disease protection. Modern sequencing and conventional methods reveal microbial community structures and environmental impacts, these information helps in microbial selection and manipulation. These studies form the foundation for using seed microbiomes to enhance crop resilience and productivity. While existing research has primarily focused on characterizing microbiota in dried mature seeds, a significant gap exists in understanding how these microbial communities assemble during seed development. The review also discusses applying seed-associated microorganisms to improve crops in the context of climate change. However, limited knowledge is available about the microbial assembly pattern on seeds, and their impact on plant growth. The review provides insight into microbial composition, functions, and significance for plant health, particularly regarding growth promotion and pest control.
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Affiliation(s)
- Ajay Kumar
- Amity Institute of Biotechnology, Amity University, Sector-125, Noida, Uttar Pradesh 201313, India
| | - Manoj Kumar Solanki
- Department of Life Sciences and Biological Sciences, IES University, Bhopal, Madhya Pradesh, India; Plant Cytogenetics and Molecular Biology Group, Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia in Katowice, Katowice, Poland.
| | - Zhen Wang
- Guangxi Key Laboratory of Agricultural Resources Chemistry and Biotechnology, Agricultural College, Yulin Normal University, Yulin 537000, China
| | - Anjali Chandrol Solanki
- Department of Agriculture, Mansarover Global University, Bhopal, Madhya Pradesh 462042, India
| | - Vipin Kumar Singh
- Department of Botany, K.S. Saket P.G. College, Ayodhya 224123, Uttar Pradesh, India
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Liu X, Zhu X, Dong Y, Chen Y, Li M, Li C. Limited Impact of Soil Microorganisms on the Endophytic Bacteria of Tartary Buckwheat ( Fagopyrum tataricum). Microorganisms 2023; 11:2085. [PMID: 37630645 PMCID: PMC10458046 DOI: 10.3390/microorganisms11082085] [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: 07/08/2023] [Revised: 08/04/2023] [Accepted: 08/11/2023] [Indexed: 08/27/2023] Open
Abstract
Soil has been considered the main microbial reservoir for plants, but the robustness of the plant microbiome when the soil resource is removed has not been greatly considered. In the present study, we tested the robustness of the microbiota recruited by Tartary buckwheat (Fagopyrum tataricum Gaertn.), grown on sterile humus soil and irrigated with sterile water. Our results showed that the microbiomes of the leaf, stem, root and next-generation seeds were comparable between treated (grown in sterile soil) and control plants (grown in non-sterile soil), indicating that the plants had alternative robust ways to shape their microbiome. Seed microbiota contributed greatly to endophyte communities in the phyllosphere, rhizosphere and next-generation seeds. The microbiome originated from the seeds conferred clear benefits to seedling growth because seedling height and the number of leaves were significantly increased when grown in sterilized soil. The overall microbiome of the plant was affected very little by the removal of the soil microbial resource. The microbial co-occurrence network exhibited more interactions, and Proteobacteria was enriched in the root of Tartary buckwheat planted in sterilized soil. Our research broadens the understanding of the general principles governing microbiome assembly and is widely applicable to both microbiome modeling and sustainable agriculture.
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Affiliation(s)
- Xuyan Liu
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China; (X.L.); (X.Z.); (Y.C.); (M.L.)
- College of Plant Protection, Yunnan Agricultural University, Kunming 650201, China
| | - Xishen Zhu
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China; (X.L.); (X.Z.); (Y.C.); (M.L.)
- College of Plant Protection, Yunnan Agricultural University, Kunming 650201, China
| | - Yumei Dong
- Yunnan-Taiwan Engineering Research Center for Characteristic Agriculture Industrialization of Yunnan Province, Yunnan Agricultural University, Kunming 650201, China;
| | - Yan Chen
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China; (X.L.); (X.Z.); (Y.C.); (M.L.)
- College of Plant Protection, Yunnan Agricultural University, Kunming 650201, China
| | - Meifang Li
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China; (X.L.); (X.Z.); (Y.C.); (M.L.)
- College of Plant Protection, Yunnan Agricultural University, Kunming 650201, China
| | - Chengyun Li
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China; (X.L.); (X.Z.); (Y.C.); (M.L.)
- Yunnan-CABI Joint Laboratory for Integrated Prevention and Control of Transboundary Pests, Yunnan Agricultural University, Kunming 650201, China
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Gola U, Kour S, Kaur T, Perveen K, Bukhari NA, Alsulami JA, Maithani D, Dasila H, Singh M, Suyal DC. Prokaryotic diversity and community structure in the rhizosphere of Lantana weed ( Lantana camara L.). FRONTIERS IN PLANT SCIENCE 2023; 14:1174859. [PMID: 37152122 PMCID: PMC10160613 DOI: 10.3389/fpls.2023.1174859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 04/03/2023] [Indexed: 05/09/2023]
Abstract
Lantana weed (Lantana camara L.) is among the most noxious weeds in the world. Keeping in mind its invasive behavior and great ecological tolerance, it becomes imperative to analyze the structure and function of associated microbiome. In this perspective, Illumina-based metagenome sequencing was performed to gain a better understanding of prokaryotic diversity and community structure in the rhizosphere soil of L. camara L. The organic carbon, nitrogen, phosphorus, and potassium contents in the rhizosphere soil were 0.91% (± 0.21%); 280 Kg ha-1 (± 4.02 Kg ha-1), 54.5 Kg ha-1 (± 3.12 Kg ha-1), and 189 Kg ha-1 (± 6.11 Kg ha-1), respectively. The metagenome analysis revealed the existence of 41 bacterial and 2 archaeal phyla, with only 12 showing ≥1% abundances. Pseudomonadota was the dominant phylum with 31.3% abundance, followed by Actinomycetota (20.9%). Further, 54 different genera were identified with the highest abundance of Devosia (2.8%). The PICRUSt analysis predicted various functional traits in the soil metagenome, with general cellular functions dominating, followed by stress tolerance. Moreover, 10% of the functions were associated with nitrogen fixation, phosphate solubilization, and potassium mobilization. In conclusion, the present study revealed the existence of diverse prokaryotic communities in the rhizosphere of the L. camara L. which was primarily associated with stress response and plant growth promotion. To the best of our knowledge, this study documents for the first time the L. camara L. microbiome. Furthermore, the identified genera can be explored for agricultural needs in future.
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Affiliation(s)
- Upasana Gola
- Department of Microbiology, Akal College of Basic Sciences, Eternal University, Baru Sahib, India
| | - Shilippreet Kour
- Department of Microbiology, Akal College of Basic Sciences, Eternal University, Baru Sahib, India
| | - Tanvir Kaur
- Department of Genetics, Plant Breeding and Biotechnology, Dr. Khem Singh Gill Akal College of Agriculture, Eternal University, Baru Sahib, India
| | - Kahkashan Perveen
- Department of Botany & Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Najat A. Bukhari
- Department of Botany & Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | | | | | - Hemant Dasila
- Department of Microbiology, Akal College of Basic Sciences, Eternal University, Baru Sahib, India
| | - Manali Singh
- Department of Biotechnology, Invertis University, Bareilly- Lucknow National Highway, Bareilly, India
| | - Deep Chandra Suyal
- Department of Microbiology, Akal College of Basic Sciences, Eternal University, Baru Sahib, India
- Vidyadayini Institute of Science, Management and Technology, Sajjan Singh Nagar, Bhopal, Madhya Pradesh, India
- *Correspondence: Deep Chandra Suyal,
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Das S, Verma S, Choudhary P, Singh R, Saxena AK. Deciphering the genetic and functional diversity of cultivable bacteria from chasmophytic pigweed ( Chenopodium album) from Tsomoriri, Ladakh, India. 3 Biotech 2022; 12:242. [PMID: 36032512 PMCID: PMC9399335 DOI: 10.1007/s13205-022-03278-0] [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: 12/08/2021] [Accepted: 07/26/2022] [Indexed: 11/01/2022] Open
Abstract
Chasmophytes are a group of diverse plants growing on cracks and crevices of rocks. They survive under nutrient and water-limited conditions. Microorganisms associated with chasmophytes may play a critical role in their survival. In the present study, 263 bacterial isolates were obtained from chasmophytic wild Chenopodium collected from Tsomoriri, Ladakh. Members of Enterobacter, Pseudomonas, Pantoea, and Alcaligenes comprised ~ 90% of the Gram-negative bacteria, while among Gram-positive, Bacillus, Solibacillus, Fictibacillus, Microbacterium, and Micrococcus were most abundant. When evaluated for various plant growth-promoting traits, 36 bacteria could solubilize insoluble phosphate, 10 bacteria could release potassium from silicate minerals, and 25 bacteria could solubilize ZnO, while 124 bacteria produced siderophores. ACC deaminase activity was present in 31 isolates, while 46 bacteria could produce IAA (10.40-232.0 μg/mL). Furthermore, more than 64% of the isolates could grow at 50 °C, while ~ 60% could grow at 4 °C. Similarly, ~ 50% isolates were able to grow with > 1.7 M NaCl and ~ 70% could grow under high osmolarity (~ 67 mOsmol/L). The ability of these microorganisms to grow under such a wide range of temperature, salinity, and osmolarity offers adaptive advantage to colonize plants surviving under harsh environmental conditions. A large number (30-49%) of these isolates could produce acids from various sugars and sugar alcohols which is crucial to release mineral nutrients trapped in the rocks. The results indicated that genetically and functionally diverse microflora associated with wild Chenopodium might be helping these plants to effectively mine nutrients and water under extreme conditions. Supplementary Information The online version contains supplementary material available at 10.1007/s13205-022-03278-0.
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Affiliation(s)
- Sudipta Das
- ICAR-National Bureau of Agriculturally Important Microorganisms (NBAIM), Mau, Uttar Pradesh India
- Amity Institute of Microbial Technology, Amity University, Noida, Uttar Pradesh India
| | - Shaloo Verma
- ICAR-National Bureau of Agriculturally Important Microorganisms (NBAIM), Mau, Uttar Pradesh India
| | - Prassan Choudhary
- ICAR-National Bureau of Agriculturally Important Microorganisms (NBAIM), Mau, Uttar Pradesh India
| | - Rajni Singh
- Amity Institute of Microbial Technology, Amity University, Noida, Uttar Pradesh India
| | - Anil Kumar Saxena
- ICAR-National Bureau of Agriculturally Important Microorganisms (NBAIM), Mau, Uttar Pradesh India
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Dumigan CR, Deyholos MK. Cannabis Seedlings Inherit Seed-Borne Bioactive and Anti-Fungal Endophytic Bacilli. PLANTS (BASEL, SWITZERLAND) 2022; 11:2127. [PMID: 36015430 PMCID: PMC9415172 DOI: 10.3390/plants11162127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 08/09/2022] [Accepted: 08/11/2022] [Indexed: 06/15/2023]
Abstract
Throughout the hundreds of millions of years of co-evolution, plants and microorganisms have established intricate symbiotic and pathogenic relationships. Microbial communities associated with plants are in constant flux and can ultimately determine whether a plant will successfully reproduce or be destroyed by their environment. Inheritance of beneficial microorganisms is an adaptation plants can use to protect germinating seeds against biotic and abiotic stresses as seedlings develop. The interest in Cannabis as a modern crop requires research into effective biocontrol of common fungal pathogens, an area that has seen little research. This study examines the seed-borne endophytes present across 15 accessions of Cannabis grown to seed across Western Canada. Both hemp and marijuana seedlings inherited a closely related group of bioactive endophytic Bacilli. All Cannabis accessions possessed seed-inherited Paenibacillus mobilis with the capacity to solubilize mineral phosphate. Additionally, seeds were found to carry genera of fungal isolates known to be Cannabis pathogens and post-harvest molds: Alternaria, Penicillium, Cladosporium, Chaetomium, Aspergillus, Rhizopus, and Fusarium. Thirteen seed-borne endophytes showed antibiotic activity against Alternaria, Aspergillus, Penicillium, and Fusarium. This study suggests both fungal pathogens and bacterial endophytes that antagonize them are vectored across generations in Cannabis as they compete over this shared niche.
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Culturable Seed Microbiota of Populus trichocarpa. Pathogens 2021; 10:pathogens10060653. [PMID: 34074042 PMCID: PMC8225106 DOI: 10.3390/pathogens10060653] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/09/2021] [Accepted: 05/17/2021] [Indexed: 11/29/2022] Open
Abstract
Plants harbor a diverse community of microbes, whose interactions with their host and each other can influence plant health and fitness. While microbiota in plant vegetative tissues has been extensively studied, less is known about members of the seed microbiota. We used culture-based surveys to identify bacteria and fungi found in the seeds of the model tree, Populus trichocarpa, collected from different sites. We found that individual P. trichocarpa seeds typically contained zero or one microbe, with common taxa including species of Cladosporium, Aureobasidium, Diaporthe, Alternaria, and Pseudomonas, a bacterium. Pseudomonas isolates were associated with seed mortality and were negatively associated with the occurrence of fungal isolates within Epicoccum, Alternaria, and Aureobasidium from the same seed. Next, we conducted an inoculation experiment with one of the isolated seed microbes, Pseudomonas syringae pv. syringae, and found that it reduced seed germination and increased seedling mortality for P. trichocarpa. Our findings highlight common fungi and bacteria in the seeds of P. trichocarpa, prompting further study of their functional consequences. Moreover, our study confirms that P. syringae pv. syringae is a seed pathogen of P. trichocarpa and is the first report that P. syringae pv. syringae is a lethal seedling pathogen of P. trichocarpa, allowing for future work on the pathogenicity of this bacterium in seedlings and potential antagonism with other seed microbes.
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Saad MM, Eida AA, Hirt H. Tailoring plant-associated microbial inoculants in agriculture: a roadmap for successful application. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:3878-3901. [PMID: 32157287 PMCID: PMC7450670 DOI: 10.1093/jxb/eraa111] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 03/09/2020] [Indexed: 05/05/2023]
Abstract
Plants are now recognized as metaorganisms which are composed of a host plant associated with a multitude of microbes that provide the host plant with a variety of essential functions to adapt to the local environment. Recent research showed the remarkable importance and range of microbial partners for enhancing the growth and health of plants. However, plant-microbe holobionts are influenced by many different factors, generating complex interactive systems. In this review, we summarize insights from this emerging field, highlighting the factors that contribute to the recruitment, selection, enrichment, and dynamic interactions of plant-associated microbiota. We then propose a roadmap for synthetic community application with the aim of establishing sustainable agricultural systems that use microbial communities to enhance the productivity and health of plants independently of chemical fertilizers and pesticides. Considering global warming and climate change, we suggest that desert plants can serve as a suitable pool of potentially beneficial microbes to maintain plant growth under abiotic stress conditions. Finally, we propose a framework for advancing the application of microbial inoculants in agriculture.
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Affiliation(s)
- Maged M Saad
- DARWIN21, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Abdul Aziz Eida
- DARWIN21, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Heribert Hirt
- DARWIN21, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Institute of Plant Sciences Paris-Saclay (IPS2), Gif-sur-Yvette Cedex, France
- Max F. Perutz Laboratories, University of Vienna, Vienna, Austria
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Kavamura VN, Robinson RJ, Hayat R, Clark IM, Hughes D, Rossmann M, Hirsch PR, Mendes R, Mauchline TH. Land Management and Microbial Seed Load Effect on Rhizosphere and Endosphere Bacterial Community Assembly in Wheat. Front Microbiol 2019; 10:2625. [PMID: 31803160 PMCID: PMC6873152 DOI: 10.3389/fmicb.2019.02625] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 10/29/2019] [Indexed: 11/13/2022] Open
Abstract
Microbial community ecology studies have traditionally utilized culture-based methodologies, though the advent of next-generation amplicon sequencing has facilitated superior resolution analyses of complex microbial communities. Here, we used culture-dependent and -independent approaches to explore the influence of land use as well as microbial seed load on bacterial community structure of the wheat rhizosphere and root endosphere. It was found that niche was an important factor in shaping the microbiome when using both methodological approaches, and that land use was also a discriminatory factor for the culture-independent-based method. Although culture-independent methods provide a higher resolution of analysis, it was found that in the rhizosphere, particular operational taxonomic units (OTUs) in the culture-dependent fraction were absent from the culture-independent fraction, indicating that deeper sequence analysis is required for this approach to be exhaustive. We also found that the microbial seed load defined the endosphere, but not rhizosphere, community structure for plants grown in soil which was not wheat adapted. Together, these findings increase our understanding of the importance of land management and microbial seed load in shaping the root microbiome of wheat and this knowledge will facilitate the exploitation of plant-microbe interactions for the development of novel microbial inoculants.
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Affiliation(s)
| | | | - Rifat Hayat
- Department of Soil Science and Soil and Water Conservation, Pir Mehr Ali Shah Arid Agriculture University, Rawalpindi, Pakistan
| | - Ian M. Clark
- Sustainable Agriculture Sciences, Rothamsted Research, Harpenden, United Kingdom
| | - David Hughes
- Computational and Analytical Sciences, Rothamsted Research, Harpenden, United Kingdom
| | - Maike Rossmann
- Laboratory of Environmental Microbiology, Embrapa Meio Ambiente, Jaguariúna, Brazil
| | - Penny R. Hirsch
- Sustainable Agriculture Sciences, Rothamsted Research, Harpenden, United Kingdom
| | - Rodrigo Mendes
- Laboratory of Environmental Microbiology, Embrapa Meio Ambiente, Jaguariúna, Brazil
| | - Tim H. Mauchline
- Sustainable Agriculture Sciences, Rothamsted Research, Harpenden, United Kingdom
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Shade A, Jacques MA, Barret M. Ecological patterns of seed microbiome diversity, transmission, and assembly. Curr Opin Microbiol 2017; 37:15-22. [PMID: 28437661 DOI: 10.1016/j.mib.2017.03.010] [Citation(s) in RCA: 164] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Accepted: 03/22/2017] [Indexed: 01/08/2023]
Abstract
Seeds are involved in the transmission of microorganisms from one plant generation to another and consequently act as the initial inoculum for the plant microbiota. The purpose of this mini-review is to provide an overview of current knowledge on the diversity, structure and role of the seed microbiota. The relative importance of the mode of transmission (vertical vs horizontal) of the microbial entities composing the seed microbiota as well as the potential connections existing between seed and other plant habitats such as the anthosphere and the spermosphere is discussed. Finally the governing processes (niche vs neutral) involved in the assembly and the dynamics of the seed microbiota are examined.
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Affiliation(s)
- Ashley Shade
- Department of Microbiology and Molecular Genetics, Program in Ecology, Evolutionary Biology, and Behavior, The DOE Great Lakes Bioenergy Research Center, The Plant Resilience Institute, Michigan State University, East Lansing MI 48824, United States
| | - Marie-Agnès Jacques
- INRA, UMR1345 Institut de Recherches en Horticulture et Semences, SFR4207 QUASAV, F-49071, Beaucouzé, France
| | - Matthieu Barret
- INRA, UMR1345 Institut de Recherches en Horticulture et Semences, SFR4207 QUASAV, F-49071, Beaucouzé, France.
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Trognitz F, Hackl E, Widhalm S, Sessitsch A. The role of plant-microbiome interactions in weed establishment and control. FEMS Microbiol Ecol 2016; 92:fiw138. [PMID: 27387910 DOI: 10.1093/femsec/fiw138] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/10/2016] [Indexed: 12/21/2022] Open
Abstract
The soil microbiome plays an important role in the establishment of weeds and invasive plants. They associate with microorganisms supporting their growth and health. Weed management strategies, like tillage and herbicide treatments, to control weeds generally alter soil structure going alongside with changes in the microbial community. Once a weed population establishes in the field, the plants build up a close relationship with the available microorganisms. Seeds or vegetative organs overwinter in soil and select early in the season their own microbiome before crop plants start to vegetate. Weed and crop plants compete for light, nutrition and water, but may differently interact with soil microorganisms. The development of new sequencing technologies for analyzing soil microbiomes has opened up the possibility for in depth analysis of the interaction between 'undesired' plants and crop plants under different management systems. These findings will help us to understand the functions of microorganisms involved in crop productivity and plant health, weed establishment and weed prevention. Exploitation of the knowledge offers the possibility to search for new biocontrol methods against weeds based on soil and plant-associated microorganisms. This review discusses the recent advances in understanding the functions of microbial communities for weed/invasive plant establishment and shows new ways to use plant-associated microorganisms to control weeds and invasive plants in different land management systems.
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Affiliation(s)
- Friederike Trognitz
- Department of Health and Environment, AIT Austrian Institute of Technology GmbH, 3430 Tulln, Austria
| | - Evelyn Hackl
- Department of Health and Environment, AIT Austrian Institute of Technology GmbH, 3430 Tulln, Austria
| | - Siegrid Widhalm
- Department of Health and Environment, AIT Austrian Institute of Technology GmbH, 3430 Tulln, Austria
| | - Angela Sessitsch
- Department of Health and Environment, AIT Austrian Institute of Technology GmbH, 3430 Tulln, Austria
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Rezki S, Campion C, Iacomi-Vasilescu B, Preveaux A, Toualbia Y, Bonneau S, Briand M, Laurent E, Hunault G, Simoneau P, Jacques MA, Barret M. Differences in stability of seed-associated microbial assemblages in response to invasion by phytopathogenic microorganisms. PeerJ 2016; 4:e1923. [PMID: 27077013 PMCID: PMC4830237 DOI: 10.7717/peerj.1923] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 03/21/2016] [Indexed: 11/20/2022] Open
Abstract
Seeds are involved in the vertical transmission of microorganisms from one plant generation to another and consequently act as reservoirs for the plant microbiota. However, little is known about the structure of seed-associated microbial assemblages and the regulators of assemblage structure. In this work, we have assessed the response of seed-associated microbial assemblages of Raphanus sativus to invading phytopathogenic agents, the bacterial strain Xanthomonas campestris pv. campestris (Xcc) 8004 and the fungal strain Alternaria brassicicola Abra43. According to the indicators of bacterial (16S rRNA gene and gyrB sequences) and fungal (ITS1) diversity employed in this study, seed transmission of the bacterial strain Xcc 8004 did not change the overall composition of resident microbial assemblages. In contrast seed transmission of Abra43 strongly modified the richness and structure of fungal assemblages without affecting bacterial assemblages. The sensitivity of seed-associated fungal assemblage to Abra43 is mostly related to changes in relative abundance of closely related fungal species that belong to the Alternaria genus. Variation in stability of the seed microbiota in response to Xcc and Abra43 invasions could be explained by differences in seed transmission pathways employed by these micro-organisms, which ultimately results in divergence in spatio-temporal colonization of the seed habitat.
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Affiliation(s)
- Samir Rezki
- Institut de Recherche en Horticulture et Semences, Institut National de la Recherche Agronomique , Beaucouzé , France
| | - Claire Campion
- Institut de Recherche en Horticulture et Semences, Université d'Angers , Beaucouzé , France
| | | | - Anne Preveaux
- Institut de Recherche en Horticulture et Semences, Institut National de la Recherche Agronomique , Beaucouzé , France
| | - Youness Toualbia
- Institut de Recherche en Horticulture et Semences, Université d'Angers , Beaucouzé , France
| | - Sophie Bonneau
- Institut de Recherche en Horticulture et Semences, Institut National de la Recherche Agronomique , Beaucouzé , France
| | - Martial Briand
- Institut de Recherche en Horticulture et Semences, Institut National de la Recherche Agronomique , Beaucouzé , France
| | - Emmanuelle Laurent
- Federation Nationale des Agriculteurs Multiplicateurs de Semences , Brain sur l'Authion , France
| | - Gilles Hunault
- Laboratoire d'Hémodynamique, Interaction Fibrose et Invasivité tumorale Hépatique, Université d'Angers , Angers , France
| | - Philippe Simoneau
- Institut de Recherche en Horticulture et Semences, Université d'Angers , Beaucouzé , France
| | - Marie-Agnès Jacques
- Institut de Recherche en Horticulture et Semences, Institut National de la Recherche Agronomique , Beaucouzé , France
| | - Matthieu Barret
- Institut de Recherche en Horticulture et Semences, Institut National de la Recherche Agronomique , Beaucouzé , France
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12
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van Overbeek LS, Saikkonen K. Impact of Bacterial-Fungal Interactions on the Colonization of the Endosphere. TRENDS IN PLANT SCIENCE 2016; 21:230-242. [PMID: 26821607 DOI: 10.1016/j.tplants.2016.01.003] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 12/15/2015] [Accepted: 01/04/2016] [Indexed: 06/05/2023]
Abstract
Research on different endophyte taxa and the related scientific disciplines have largely developed separately, and comprehensive community-level studies on bacterial and fungal interactions and their importance are lacking. Here, we discuss the transmission modes of bacteria and fungi and the nature of their interactions in the endosphere at both the molecular and physiological level. Mixed-community biofilms in the endosphere may have a role in protecting endophytes against encountered stresses, such as from plant defense systems. However, transmission from static (in biofilms) to free-living (planktonic) forms may be crucial for the exploration of new habitable spaces in plants. Important features previously recognized as plant-microbe interactions or antagonism in endophyte genomes and metagenomes are proposed to have essential roles in the modulation of endophyte communities.
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Affiliation(s)
- Leonard S van Overbeek
- Wageningen University and Research Centre, Droevendaalsesteeg 1, PO Box 16, 6700AA, Wageningen, The Netherlands.
| | - Kari Saikkonen
- Natural Resources Institute Finland (Luke), Management and Production of Renewable Resources, Itäinen Pitkäkatu 3, 20520 Turku, Finland.
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Aschenbrenner IA, Cernava T, Berg G, Grube M. Understanding Microbial Multi-Species Symbioses. Front Microbiol 2016; 7:180. [PMID: 26925047 PMCID: PMC4757690 DOI: 10.3389/fmicb.2016.00180] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 02/02/2016] [Indexed: 11/13/2022] Open
Abstract
Lichens are commonly recognized as a symbiotic association of a fungus and a chlorophyll containing partner, either green algae or cyanobacteria, or both. The fungus provides a suitable habitat for the partner, which provides photosynthetically fixed carbon as energy source for the system. The evolutionary result of the self-sustaining partnership is a unique joint structure, the lichen thallus, which is indispensable for fungal sexual reproduction. The classical view of a dual symbiosis has been challenged by recent microbiome research, which revealed host-specific bacterial microbiomes. The recent results about bacterial associations with lichens symbioses corroborate their notion as a multi-species symbiosis. Multi-omics approaches have provided evidence for functional contribution by the bacterial microbiome to the entire lichen meta-organism while various abiotic and biotic factors can additionally influence the bacterial community structure. Results of current research also suggest that neighboring ecological niches influence the composition of the lichen bacterial microbiome. Specificity and functions are here reviewed based on these recent findings, converging to a holistic view of bacterial roles in lichens. Finally we propose that the lichen thallus has also evolved to function as a smart harvester of bacterial symbionts. We suggest that lichens represent an ideal model to study multi-species symbiosis, using the recently available omics tools and other cutting edge methods.
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Affiliation(s)
- Ines A. Aschenbrenner
- Institute of Environmental Biotechnology, Graz University of TechnologyPetersgasse, Graz, Austria
- Institute of Plant Sciences, University of GrazGraz, Austria
| | - Tomislav Cernava
- Institute of Environmental Biotechnology, Graz University of TechnologyPetersgasse, Graz, Austria
- Austrian Centre of Industrial Biotechnology – Gesellschaft mit beschränkter HaftungGraz, Austria
| | - Gabriele Berg
- Institute of Environmental Biotechnology, Graz University of TechnologyPetersgasse, Graz, Austria
| | - Martin Grube
- Institute of Plant Sciences, University of GrazGraz, Austria
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Hardoim PR, van Overbeek LS, Berg G, Pirttilä AM, Compant S, Campisano A, Döring M, Sessitsch A. The Hidden World within Plants: Ecological and Evolutionary Considerations for Defining Functioning of Microbial Endophytes. Microbiol Mol Biol Rev 2015; 79:293-320. [PMID: 26136581 PMCID: PMC4488371 DOI: 10.1128/mmbr.00050-14] [Citation(s) in RCA: 1036] [Impact Index Per Article: 115.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
All plants are inhabited internally by diverse microbial communities comprising bacterial, archaeal, fungal, and protistic taxa. These microorganisms showing endophytic lifestyles play crucial roles in plant development, growth, fitness, and diversification. The increasing awareness of and information on endophytes provide insight into the complexity of the plant microbiome. The nature of plant-endophyte interactions ranges from mutualism to pathogenicity. This depends on a set of abiotic and biotic factors, including the genotypes of plants and microbes, environmental conditions, and the dynamic network of interactions within the plant biome. In this review, we address the concept of endophytism, considering the latest insights into evolution, plant ecosystem functioning, and multipartite interactions.
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Affiliation(s)
- Pablo R. Hardoim
- Centre of Marine Sciences, University of Algarve, Faro, Portugal
| | | | - Gabriele Berg
- Institute for Environmental Biotechnology, Graz University of Technology, Graz, Austria
| | | | - Stéphane Compant
- Department of Health and Environment, Bioresources Unit, Austrian Institute of Technology GmbH, Tulln, Austria
| | - Andrea Campisano
- Sustainable Agro-Ecosystems and Bioresources Department, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige, TN, Italy
| | | | - Angela Sessitsch
- Department of Health and Environment, Bioresources Unit, Austrian Institute of Technology GmbH, Tulln, Austria
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15
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Klaedtke S, Jacques MA, Raggi L, Préveaux A, Bonneau S, Negri V, Chable V, Barret M. Terroir is a key driver of seed-associated microbial assemblages. Environ Microbiol 2015; 18:1792-804. [PMID: 26171841 DOI: 10.1111/1462-2920.12977] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 07/01/2015] [Indexed: 12/20/2022]
Abstract
Seeds have evolved in association with diverse microbial assemblages that may influence plant growth and health. However, little is known about the composition of seed-associated microbial assemblages and the ecological processes shaping their structures. In this work, we monitored the relative influence of the host genotypes and terroir on the structure of the seed microbiota through metabarcoding analysis of different microbial assemblages associated to five different bean cultivars harvested in two distinct farms. Overall, few bacterial and fungal operational taxonomic units (OTUs) were conserved across all seed samples. The lack of shared OTUs between samples is explained by a significant effect of the farm site on the structure of microbial assemblage, which explained 12.2% and 39.7% of variance in bacterial and fungal diversity across samples. This site-specific effect is reflected by the significant enrichment of 70 OTUs in Brittany and 88 OTUs in Luxembourg that lead to differences in co-occurrence patterns. In contrast, variance in microbial assemblage structure was not explained by host genotype. Altogether, these results suggest that seed-associated microbial assemblage is determined by niche-based processes and that the terroir is a key driver of these selective forces.
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Affiliation(s)
| | - Marie-Agnès Jacques
- UMR1345 Institut de Recherches en Horticulture et Semences, INRA, SFR4207 QUASAV, F-49071, Beaucouzé, France
| | - Lorenzo Raggi
- Dipartimento di Scienze Agrarie, Alimentari e Ambientali, Università degli Studi di Perugia, Borgo XX Giugno 74, 06121, Perugia, Italy
| | - Anne Préveaux
- UMR1345 Institut de Recherches en Horticulture et Semences, INRA, SFR4207 QUASAV, F-49071, Beaucouzé, France
| | - Sophie Bonneau
- UMR1345 Institut de Recherches en Horticulture et Semences, INRA, SFR4207 QUASAV, F-49071, Beaucouzé, France
| | - Valeria Negri
- Dipartimento di Scienze Agrarie, Alimentari e Ambientali, Università degli Studi di Perugia, Borgo XX Giugno 74, 06121, Perugia, Italy
| | - Véronique Chable
- UR980, INRA SAD, 65 Rue de St. Brieuc, CS 84215, 35042, Rennes, France
| | - Matthieu Barret
- UMR1345 Institut de Recherches en Horticulture et Semences, INRA, SFR4207 QUASAV, F-49071, Beaucouzé, France
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16
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The Hidden World within Plants: Ecological and Evolutionary Considerations for Defining Functioning of Microbial Endophytes. Microbiol Mol Biol Rev 2015. [PMID: 26136581 DOI: 10.1128/mmbr.00050-14.] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
All plants are inhabited internally by diverse microbial communities comprising bacterial, archaeal, fungal, and protistic taxa. These microorganisms showing endophytic lifestyles play crucial roles in plant development, growth, fitness, and diversification. The increasing awareness of and information on endophytes provide insight into the complexity of the plant microbiome. The nature of plant-endophyte interactions ranges from mutualism to pathogenicity. This depends on a set of abiotic and biotic factors, including the genotypes of plants and microbes, environmental conditions, and the dynamic network of interactions within the plant biome. In this review, we address the concept of endophytism, considering the latest insights into evolution, plant ecosystem functioning, and multipartite interactions.
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17
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Barret M, Briand M, Bonneau S, Préveaux A, Valière S, Bouchez O, Hunault G, Simoneau P, Jacques MA. Emergence shapes the structure of the seed microbiota. Appl Environ Microbiol 2015; 81:1257-66. [PMID: 25501471 PMCID: PMC4309697 DOI: 10.1128/aem.03722-14] [Citation(s) in RCA: 146] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 12/04/2014] [Indexed: 11/20/2022] Open
Abstract
Seeds carry complex microbial communities, which may exert beneficial or deleterious effects on plant growth and plant health. To date, the composition of microbial communities associated with seeds has been explored mainly through culture-based diversity studies and therefore remains largely unknown. In this work, we analyzed the structures of the seed microbiotas of different plants from the family Brassicaceae and their dynamics during germination and emergence through sequencing of three molecular markers: the ITS1 region of the fungal internal transcribed spacer, the V4 region of 16S rRNA gene, and a species-specific bacterial marker based on a fragment of gyrB. Sequence analyses revealed important variations in microbial community composition between seed samples. Moreover, we found that emergence strongly influences the structure of the microbiota, with a marked reduction of bacterial and fungal diversity. This shift in the microbial community composition is mostly due to an increase in the relative abundance of some bacterial and fungal taxa possessing fast-growing abilities. Altogether, our results provide an estimation of the role of the seed as a source of inoculum for the seedling, which is crucial for practical applications in developing new strategies of inoculation for disease prevention.
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Affiliation(s)
- Matthieu Barret
- INRA, UMR1345 Institut de Recherche en Horticulture et Semences, Beaucouzé, France
- Agrocampus Ouest, UMR1345 Institut de Recherche en Horticulture et Semences, Beaucouzé, France
- Université d'Angers, UMR1345 Institut de Recherche en Horticulture et Semences, SFR4207 QUASAV, Beaucouzé, France
| | - Martial Briand
- INRA, UMR1345 Institut de Recherche en Horticulture et Semences, Beaucouzé, France
- Agrocampus Ouest, UMR1345 Institut de Recherche en Horticulture et Semences, Beaucouzé, France
- Université d'Angers, UMR1345 Institut de Recherche en Horticulture et Semences, SFR4207 QUASAV, Beaucouzé, France
| | - Sophie Bonneau
- INRA, UMR1345 Institut de Recherche en Horticulture et Semences, Beaucouzé, France
- Agrocampus Ouest, UMR1345 Institut de Recherche en Horticulture et Semences, Beaucouzé, France
- Université d'Angers, UMR1345 Institut de Recherche en Horticulture et Semences, SFR4207 QUASAV, Beaucouzé, France
| | - Anne Préveaux
- INRA, UMR1345 Institut de Recherche en Horticulture et Semences, Beaucouzé, France
- Agrocampus Ouest, UMR1345 Institut de Recherche en Horticulture et Semences, Beaucouzé, France
- Université d'Angers, UMR1345 Institut de Recherche en Horticulture et Semences, SFR4207 QUASAV, Beaucouzé, France
| | - Sophie Valière
- GeT-PlaGe, Genotoul, INRA Auzeville, Castanet-Tolosan, France
- INRA, UAR1209, Département de Génétique Animale, INRA Auzeville, Castanet Tolosan, France
| | - Olivier Bouchez
- GeT-PlaGe, Genotoul, INRA Auzeville, Castanet-Tolosan, France
- UMR INRA/INPT ENSAT/INPT ENVT, Génétique, Physiologie et Systèmes d'Élevage, INRA Auzeville, Castanet Tolosan, France
| | - Gilles Hunault
- Université d'Angers, Laboratoire d'Hémodynamique, Interaction Fibrose et Invasivité Tumorale Hépatique, UPRES 3859, IFR 132, Angers, France
| | - Philippe Simoneau
- INRA, UMR1345 Institut de Recherche en Horticulture et Semences, Beaucouzé, France
- Agrocampus Ouest, UMR1345 Institut de Recherche en Horticulture et Semences, Beaucouzé, France
- Université d'Angers, UMR1345 Institut de Recherche en Horticulture et Semences, SFR4207 QUASAV, Beaucouzé, France
| | - Marie-Agnès Jacques
- INRA, UMR1345 Institut de Recherche en Horticulture et Semences, Beaucouzé, France
- Agrocampus Ouest, UMR1345 Institut de Recherche en Horticulture et Semences, Beaucouzé, France
- Université d'Angers, UMR1345 Institut de Recherche en Horticulture et Semences, SFR4207 QUASAV, Beaucouzé, France
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Lopez-Velasco G, Carder PA, Welbaum GE, Ponder MA. Diversity of the spinach (Spinacia oleracea) spermosphere and phyllosphere bacterial communities. FEMS Microbiol Lett 2013; 346:146-54. [PMID: 23859062 DOI: 10.1111/1574-6968.12216] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 07/03/2013] [Indexed: 11/27/2022] Open
Abstract
The bacterial diversity of seeds, transmission of bacteria from seed to phyllosphere, and fate of seed-transmitted bacteria on mature plants are poorly characterized. Understanding the dynamics of microbial communities is important for finding bio-control or mitigation strategies for human and plant pathogens. Bacterial populations colonizing spermosphere and phyllosphere of spinach (Spinacia oleracea) seedlings and plants were characterized using pyrosequencing of 16S rRNA gene amplicons. Spinach seed microbiota was composed of three bacterial phyla: Proteobacteria, Firmicutes and Actinobacteria, belonging to > 250 different operational taxonomic units (OTUs). Seed and cotyledon bacterial communities were similar in richness and diversity. Richness of 3-4 leaf-stage of development plants increased markedly to > 850 OTUs classified within 11 phyla. Although some bacterial OTUs were detected on seeds, cotyledons and plants, the breadth of new sequences indicates the importance of multiple sources outside the seed in shaping phyllosphere community. Most classified sequences were from previously undescribed taxa, highlighting the benefits of pyrosequencing in describing seed diversity and phyllosphere bacterial communities. Bacterial community richness increased from 250 different OTUs for spinach seeds and cotyledons, to 800 OTUs for seedlings. To our knowledge this is the first comprehensive characterization of the spinach microbiome, complementing previous culture-based and clone library studies.
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Affiliation(s)
- Gabriela Lopez-Velasco
- Department of Food Science and Technology, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
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Fürnkranz M, Lukesch B, Müller H, Huss H, Grube M, Berg G. Microbial diversity inside pumpkins: microhabitat-specific communities display a high antagonistic potential against phytopathogens. MICROBIAL ECOLOGY 2012; 63:418-28. [PMID: 21947430 DOI: 10.1007/s00248-011-9942-4] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Accepted: 09/05/2011] [Indexed: 05/05/2023]
Abstract
Recent and substantial yield losses of Styrian oil pumpkin (Cucurbita pepo L. subsp. pepo var. styriaca Greb.) are primarily caused by the ascomycetous fungus Didymella bryoniae but bacterial pathogens are frequently involved as well. The diversity of endophytic microbial communities from seeds (spermosphere), roots (endorhiza), flowers (anthosphere), and fruits (carposphere) of three different pumpkin cultivars was studied to develop a biocontrol strategy. A multiphasic approach combining molecular, microscopic, and cultivation techniques was applied to select a consortium of endophytes for biocontrol. Specific community structures for Pseudomonas and Bacillus, two important plant-associated genera, were found for each microenvironment by fingerprinting of 16S ribosomal RNA genes. All microenvironments were dominated by bacteria; fungi were less abundant. Of the 2,320 microbial isolates analyzed in dual culture assays, 165 (7%) were tested positively for in vitro antagonism against D. bryoniae. Out of these, 43 isolates inhibited the growth of bacterial pumpkin pathogens (Pectobacterium carotovorum, Pseudomonas viridiflava, Xanthomonas cucurbitae); here only bacteria were selected. Microenvironment-specific antagonists were found, and the spermosphere and anthosphere were revealed as underexplored reservoirs for antagonists. In the latter, a potential role of pollen grains as bacterial vectors between flowers was recognized. Six broad spectrum antagonists selected according to their activity, genotypic diversity, and occurrence were evaluated under greenhouse conditions. Disease severity on pumpkins of D. bryoniae was significantly reduced by Pseudomonas chlororaphis treatment and by a combined treatment of strains (Lysobacter gummosus, P. chlororaphis, Paenibacillus polymyxa, and Serratia plymuthica). This result provides a promising prospect to biologically control pumpkin diseases.
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Affiliation(s)
- Michael Fürnkranz
- Institute of Environmental Biotechnology, Graz University of Technology, Petersgasse 12, Graz, Austria
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Sphagnum mosses harbour highly specific bacterial diversity during their whole lifecycle. ISME JOURNAL 2011; 6:802-13. [PMID: 22094342 DOI: 10.1038/ismej.2011.151] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Knowledge about Sphagnum-associated microbial communities, their structure and their origin is important to understand and maintain climate-relevant Sphagnum-dominated bog ecosystems. We studied bacterial communities of two cosmopolitan Sphagnum species, which are well adapted to different abiotic parameters (Sphagnum magellanicum, which are strongly acidic and ombrotrophic, and Sphagnum fallax, which are weakly acidic and mesotrophic), in three Alpine bogs in Austria by a multifaceted approach. Great differences between bacterial fingerprints of both Sphagna were found independently from the site. This remarkable specificity was confirmed by a cloning and a deep sequencing approach. Besides the common Alphaproteobacteria, we found a discriminative spectrum of bacteria; although Gammaproteobacteria dominated S. magellanicum, S. fallax was mainly colonised by Verrucomicrobia and Planctomycetes. Using this information for fluorescent in situ hybridisation analyses, corresponding colonisation patterns for Alphaproteobacteria and Planctomycetes were detected. Bacterial colonies were found in high abundances inside the dead big hyalocytes, but they were always connected with the living chlorocytes. Using multivariate statistical analysis, the abiotic factors nutrient richness and pH were identified to modulate the composition of Sphagnum-specific bacterial communities. Interestingly, we found that the immense bacterial diversity was transferred via the sporophyte to the gametophyte, which can explain the high specificity of Sphagnum-associated bacteria over long distances. In contrast to higher plants, which acquire their bacteria mainly from the environment, mosses as the phylogenetically oldest land plants maintain their bacterial diversity within the whole lifecycle.
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