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Rodriguez PA, Rothballer M, Chowdhury SP, Nussbaumer T, Gutjahr C, Falter-Braun P. Systems Biology of Plant-Microbiome Interactions. MOLECULAR PLANT 2019; 12:804-821. [PMID: 31128275 DOI: 10.1016/j.molp.2019.05.006] [Citation(s) in RCA: 192] [Impact Index Per Article: 38.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 05/07/2019] [Accepted: 05/15/2019] [Indexed: 05/02/2023]
Abstract
In natural environments, plants are exposed to diverse microbiota that they interact with in complex ways. While plant-pathogen interactions have been intensely studied to understand defense mechanisms in plants, many microbes and microbial communities can have substantial beneficial effects on their plant host. Such beneficial effects include improved acquisition of nutrients, accelerated growth, resilience against pathogens, and improved resistance against abiotic stress conditions such as heat, drought, and salinity. However, the beneficial effects of bacterial strains or consortia on their host are often cultivar and species specific, posing an obstacle to their general application. Remarkably, many of the signals that trigger plant immune responses are molecularly highly similar and often identical in pathogenic and beneficial microbes. Thus, it is unclear what determines the outcome of a particular microbe-host interaction and which factors enable plants to distinguish beneficials from pathogens. To unravel the complex network of genetic, microbial, and metabolic interactions, including the signaling events mediating microbe-host interactions, comprehensive quantitative systems biology approaches will be needed.
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Affiliation(s)
- Patricia A Rodriguez
- Institute of Network Biology (INET), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich, Germany
| | - Michael Rothballer
- Institute of Network Biology (INET), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich, Germany
| | - Soumitra Paul Chowdhury
- Institute of Network Biology (INET), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich, Germany
| | - Thomas Nussbaumer
- Institute of Network Biology (INET), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich, Germany; Institute of Environmental Medicine (IEM), UNIKA-T, Technical University of Munich, Augsburg, Germany
| | - Caroline Gutjahr
- Plant Genetics, TUM School of Life Science Weihenstephan, Technical University of Munich (TUM), Freising, Germany
| | - Pascal Falter-Braun
- Institute of Network Biology (INET), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich, Germany; Microbe-Host Interactions, Faculty of Biology, Ludwig-Maximilians-Universität (LMU) München, Munich, Germany.
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Tian L, Chang C, Ma L, Nasir F, Zhang J, Li W, Tran LSP, Tian C. Comparative study of the mycorrhizal root transcriptomes of wild and cultivated rice in response to the pathogen Magnaporthe oryzae. RICE (NEW YORK, N.Y.) 2019; 12:35. [PMID: 31076886 PMCID: PMC6510786 DOI: 10.1186/s12284-019-0287-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 04/09/2019] [Indexed: 05/21/2023]
Abstract
BACKGROUND Rice, which serves as a staple food for more than half of the world's population, is very susceptible to the pathogenic fungus, Magnaporthe oryzae. However, common wild rice (Oryza rufipogon), which is the ancestor of Asian cultivated rice (O. sativa), has significant potential as a genetic source of resistance to M. oryzae. Recent studies have shown that the domestication of rice has altered its relationship to symbiotic arbuscular mycorrhizae. A comparative response of wild and domestic rice inhabited by mycorrhizae to infection by M. oryzae has not been documented. RESULTS In the current study, roots of wild and cultivated rice colonized with the arbuscular mycorrhizal (AM) fungus (AMF) Rhizoglomus intraradices were used to compare the transcriptomic responses of the two species to infection by M. oryzae. Phenotypic analysis indicated that the colonization of wild and cultivated rice with R. intraradices improved the resistance of both genotypes to M. oryzae. Wild AM rice, however, was more resistant to M. oryzae than the cultivated AM rice, as well as nonmycorrhizal roots of wild rice. Transcriptome analysis indicated that the mechanisms regulating the responses of wild and cultivated AM rice to M. oryzae invasion were significantly different. The expression of a greater number of genes was changed in wild AM rice than in cultivated AM rice in response to the pathogen. Both wild and cultivated AM rice exhibited a shared response to M. oryzae which included genes related to the auxin and salicylic acid pathways; all of these play important roles in pathogenesis-related protein synthesis. In wild AM rice, secondary metabolic and biotic stress-related analyses indicated that the jasmonic acid synthesis-related α-linolenic acid pathway, the phenolic and terpenoid pathways, as well as the phenolic and terpenoid syntheses-related mevalonate (MVA) pathway were more affected by the pathogen. Genes related to these pathways were more significantly enriched in wild AM rice than in cultivated AM rice in response to M. oryzae. On the other hand, genes associated with the 'brassinosteroid biosynthesis' were more enriched in cultivated AM rice. CONCLUSIONS The AMF R. intraradices-colonized rice plants exhibited greater resistance to M. oryzae than non-AMF-colonized plants. The findings of the current study demonstrate the potential effects of crop domestication on the benefits received by the host via root colonization with AMF(s), and provide new information on the underlying molecular mechanisms. In addition, results of this study can also help develop guidelines for the applications of AMF(s) when planting rice.
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Affiliation(s)
- Lei Tian
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102 China
| | - Chunling Chang
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Lina Ma
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Fahad Nasir
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102 China
- School of Life Sciences, Northeast Normal University, Changchun City, Jilin China
| | - Jianfeng Zhang
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102 China
- College of Life Science, Jilin Agricultural University, Changchun, Jilin China
| | - Weiqiang Li
- Stress Adaptation Research Unit, RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi, Yokohama, 230-0045 Japan
| | - Lam-Son Phan Tran
- Stress Adaptation Research Unit, RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi, Yokohama, 230-0045 Japan
- Institute of Research and Development, Duy Tan University, 03 Quang Trung, Da Nang, 550000 Vietnam
| | - Chunjie Tian
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102 China
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Ruiz Gómez FJ, Navarro-Cerrillo RM, Pérez-de-Luque A, Oβwald W, Vannini A, Morales-Rodríguez C. Assessment of functional and structural changes of soil fungal and oomycete communities in holm oak declined dehesas through metabarcoding analysis. Sci Rep 2019; 9:5315. [PMID: 30926869 PMCID: PMC6441054 DOI: 10.1038/s41598-019-41804-y] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 03/15/2019] [Indexed: 12/12/2022] Open
Abstract
Forest decline is nowadays a major challenge for ecosystem sustainability. Dehesas, which consists of savannah-like mediterranean ecosystems, are threatened by the holm oak decline in the south-west of Iberian Peninsula. Phytophthora cinnamomi is considered the main agent of holm oak root rot, but little is known about the relationship between diversity of soilborne microbial community and the decline syndrome of holm oak. It would be hypothesized that the changes in the structure and functionality of the soil microbiome might influence tree health status through changes in richness and diversity of beneficial organisms such as mycorrhizal species, or fungal plant pathogens such as Fusarium spp. or Alternaria spp. Total DNA of soil samples from declined oak dehesas was extracted and analyzed through metabarcoding techniques, to evaluate the specific composition and diversity of the fungal and oomycete communities and their relationship with the disease symptoms. The fungal community included a wide range of pathogens and abundance of ectomycorrhizal key taxa related with low defoliation degree. Phytophthora cinnamomi and Pythium spiculum did not appear among the most abundant oomycetes, nor were they related directly to defoliation levels. Moreover, a particular taxon belonging to the genus Trichoderma was strongly correlated with the scarcity of pathogenic Phytophthora spp. The diversity and composition of fungal and oomycete communities were related to the severity of the decline symptoms. The metabarcoding study of microbiome represents a powerful tool to develop biocontrol strategies for the management of the holm oak root rot.
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Affiliation(s)
- Francisco J Ruiz Gómez
- Departamento de Ingeniería Forestal, Laboratorio de Ecofisiología de Sistemas Forestales ECSIFOR- ERSAF. Universidad de Córdoba. Campus de Rabanales, Crta. IV, km. 396, E-14071, Córdoba, Spain.
| | - Rafael M Navarro-Cerrillo
- Departamento de Ingeniería Forestal, Laboratorio de Ecofisiología de Sistemas Forestales ECSIFOR- ERSAF. Universidad de Córdoba. Campus de Rabanales, Crta. IV, km. 396, E-14071, Córdoba, Spain
| | - Alejandro Pérez-de-Luque
- Área de Genómica y Biotecnología, IFAPA, Centro Alameda del Obispo, Avda. Menéndez Pidal s/n, Apdo, 3092, 14080, Córdoba, Spain
| | - Wolfgang Oβwald
- Fachgebiet Pathologie der Waldbäume, Technische Universität München. Hans-Carl-von-Carlowitz-Platz 2, 85354, Freising, Germany
| | - Andrea Vannini
- Department for Innovation in Biological, Agro-food and Forest systems (DIBAF) -University of Tuscia, Via San Camillo de Lellis snc, Viterbo, 01100, Italy
| | - Carmen Morales-Rodríguez
- Fachgebiet Pathologie der Waldbäume, Technische Universität München. Hans-Carl-von-Carlowitz-Platz 2, 85354, Freising, Germany
- Department for Innovation in Biological, Agro-food and Forest systems (DIBAF) -University of Tuscia, Via San Camillo de Lellis snc, Viterbo, 01100, Italy
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Romera FJ, García MJ, Lucena C, Martínez-Medina A, Aparicio MA, Ramos J, Alcántara E, Angulo M, Pérez-Vicente R. Induced Systemic Resistance (ISR) and Fe Deficiency Responses in Dicot Plants. FRONTIERS IN PLANT SCIENCE 2019; 10:287. [PMID: 30915094 PMCID: PMC6421314 DOI: 10.3389/fpls.2019.00287] [Citation(s) in RCA: 98] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 02/21/2019] [Indexed: 05/03/2023]
Abstract
Plants develop responses to abiotic stresses, like Fe deficiency. Similarly, plants also develop responses to cope with biotic stresses provoked by biological agents, like pathogens and insects. Some of these responses are limited to the infested damaged organ, but other responses systemically spread far from the infested organ and affect the whole plant. These latter responses include the Systemic Acquired Resistance (SAR) and the Induced Systemic Resistance (ISR). SAR is induced by pathogens and insects while ISR is mediated by beneficial microbes living in the rhizosphere, like bacteria and fungi. These root-associated mutualistic microbes, besides impacting on plant nutrition and growth, can further boost plant defenses, rendering the entire plant more resistant to pathogens and pests. In the last years, it has been found that ISR-eliciting microbes can induce both physiological and morphological responses to Fe deficiency in dicot plants. These results suggest that the regulation of both ISR and Fe deficiency responses overlap, at least partially. Indeed, several hormones and signaling molecules, like ethylene (ET), auxin, and nitric oxide (NO), and the transcription factor MYB72, emerged as key regulators of both processes. This convergence between ISR and Fe deficiency responses opens the way to the use of ISR-eliciting microbes as Fe biofertilizers as well as biopesticides. This review summarizes the progress in the understanding of the molecular overlap in the regulation of ISR and Fe deficiency responses in dicot plants. Root-associated mutualistic microbes, rhizobacteria and rhizofungi species, known for their ability to induce morphological and/or physiological responses to Fe deficiency in dicot plant species are also reviewed herein.
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Affiliation(s)
- Francisco J. Romera
- Department of Agronomy, Campus de Excelencia Internacional Agroalimentario CeiA3, Universidad de Córdoba, Córdoba, Spain
| | - María J. García
- Department of Botany, Ecology and Plant Physiology, Campus de Excelencia Internacional Agroalimentario CeiA3, Universidad de Córdoba, Córdoba, Spain
| | - Carlos Lucena
- Department of Botany, Ecology and Plant Physiology, Campus de Excelencia Internacional Agroalimentario CeiA3, Universidad de Córdoba, Córdoba, Spain
| | - Ainhoa Martínez-Medina
- Molecular Interaction Ecology, German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
| | - Miguel A. Aparicio
- Department of Microbiology, Campus de Excelencia Internacional Agroalimentario CeiA3, Universidad de Córdoba, Córdoba, Spain
| | - José Ramos
- Department of Microbiology, Campus de Excelencia Internacional Agroalimentario CeiA3, Universidad de Córdoba, Córdoba, Spain
| | - Esteban Alcántara
- Department of Agronomy, Campus de Excelencia Internacional Agroalimentario CeiA3, Universidad de Córdoba, Córdoba, Spain
| | - Macarena Angulo
- Department of Agronomy, Campus de Excelencia Internacional Agroalimentario CeiA3, Universidad de Córdoba, Córdoba, Spain
| | - Rafael Pérez-Vicente
- Department of Botany, Ecology and Plant Physiology, Campus de Excelencia Internacional Agroalimentario CeiA3, Universidad de Córdoba, Córdoba, Spain
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Majeed A, Muhammad Z, Ahmad H. Plant growth promoting bacteria: role in soil improvement, abiotic and biotic stress management of crops. PLANT CELL REPORTS 2018; 37:1599-1609. [PMID: 30178214 DOI: 10.1007/s00299-018-2341-2] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 08/29/2018] [Indexed: 06/08/2023]
Abstract
Agricultural production-a major contributing factor towards global food supply-is highly reliant on field crops which are under severe threats ranging from poor soil quality, biotic, abiotic stresses and changing climatic conditions. To overcome these challenges, larger exertions are required to boost production of agricultural crops in a defensible mode. Since the evolution of fertilizers and pesticides, global crop productivity has experienced an unprecedented elevation, but at the cost of environmental and ecological unsustainability. To enhance the agricultural outputs in a sustainable way, the novel and eco-friendly strategies must be employed in agriculture, which would lead to reduced use of hazardous chemicals. Thus, the utilization of our knowledge about natural growth stimulators can lead to decrease reliance on fertilizers and pesticide which are widely used for increasing crop productivity. Among beneficial microbes, plant growth promoting bacteria offers excellent opportunities for their wide utilization in agriculture to manage soil quality and other factors which correspond to limited growth and yield output of major field crops. The aim of this review is to examine the potential role of plant growth stimulating bacteria in soil fertility and enabling crops to cope with biotic and abiotic challenges.
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Affiliation(s)
- Abdul Majeed
- Department of Botany, Government Degree College Naguman Peshawar, Peshawar, Khyber Pakhtunkhwa, Pakistan.
| | - Zahir Muhammad
- Department of Botany, University of Peshawar, Peshawar, Khyber Pakhtunkhwa, Pakistan
| | - Habib Ahmad
- Islamia College University Peshawar, Peshawar, Khyber Pakhtunkhwa, Pakistan
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Pétriacq P, López A, Luna E. Fruit Decay to Diseases: Can Induced Resistance and Priming Help? PLANTS (BASEL, SWITZERLAND) 2018; 7:E77. [PMID: 30248893 PMCID: PMC6314081 DOI: 10.3390/plants7040077] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 09/18/2018] [Accepted: 09/20/2018] [Indexed: 11/16/2022]
Abstract
Humanity faces the challenge of having to increase food production to feed an exponentially growing world population, while crop diseases reduce yields to levels that we can no longer afford. Besides, a significant amount of waste is produced after fruit harvest. Fruit decay due to diseases at a post-harvest level can claim up to 50% of the total production worldwide. Currently, the most effective means of disease control is the use of pesticides. However, their use post-harvest is extremely limited due to toxicity. The last few decades have witnessed the development of safer methods of disease control post-harvest. They have all been included in programs with the aim of achieving integrated pest (and disease) management (IPM) to reduce pesticide use to a minimum. Unfortunately, these approaches have failed to provide robust solutions. Therefore, it is necessary to develop alternative strategies that would result in effective control. Exploiting the immune capacity of plants has been described as a plausible route to prevent diseases post-harvest. Post-harvest-induced resistance (IR) through the use of safer chemicals from biological origin, biocontrol, and physical means has also been reported. In this review, we summarize the successful activity of these different strategies and explore the mechanisms behind. We further explore the concept of priming, and how its long-lasting and broad-spectrum nature could contribute to fruit resistance.
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Affiliation(s)
- Pierre Pétriacq
- UMR 1332 Biologie du Fruit et Pathologie, Université de Bordeaux et INRA de Bordeaux, F-33883 Villenave d'Ornon, France.
- Plateforme Métabolome Bordeaux-MetaboHUB, Centre de Génomique Fonctionnelle Bordeaux, IBVM, Centre INRA Bordeaux, F-33140 Villenave d'Ornon, France.
| | - Ana López
- Department of Plant Molecular Genetics, Spanish National Centre for Biotechnology, 28049 Madrid, Spain.
| | - Estrella Luna
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
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Li Q, Yan L, Ye L, Zhou J, Zhang B, Peng W, Zhang X, Li X. Chinese Black Truffle ( Tuber indicum) Alters the Ectomycorrhizosphere and Endoectomycosphere Microbiome and Metabolic Profiles of the Host Tree Quercus aliena. Front Microbiol 2018; 9:2202. [PMID: 30283422 PMCID: PMC6156548 DOI: 10.3389/fmicb.2018.02202] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 08/28/2018] [Indexed: 01/06/2023] Open
Abstract
Truffles are one group of the most famous ectomycorrhizal fungi in the world. There is little information on the ecological mechanisms of truffle ectomycorrhizal synthesis in vitro. In this study, we investigated the ecological effects of Tuber indicum – Quercus aliena ectomycorrhizal synthesis on microbial communities in the host plant roots and the surrounding soil using high-throughput sequencing and on the metabolic profiles of host plant roots using metabolomics approaches. We observed an increase in the diversity and richness of prokaryotic communities and a decrease in richness of fungal communities in the presence of T. indicum. The microbial community structures in the host roots and the surrounding soil were altered by ectomycorrhizal synthesis in the greenhouse. Bacterial genera Pedomicrobium, Variibacter, and Woodsholea and fungal genera Aspergillus, Phaeoacremonium, and Pochonia were significantly more abundant in ectomycorhizae and the ectomycorrhizosphere soil compared with the corresponding T. indicum-free controls (P < 0.05). Truffle-colonization reduced the abundance of some fungal genera surrounding the host tree, such as Acremonium, Aspergillus, and Penicillium. Putative prokaryotic metabolic functions and fungal functional groups (guilds) were also differentiated by ectomycorrhizal synthesis. The ectomycorrhizal synthesis had great impact on the measured soil physicochemical properties. Metabolic profiling analysis uncovered 55 named differentially abundant metabolites between the ectomycorhizae and the control roots, including 44 upregulated and 11 downregulated metabolites. Organic acids and carbohydrates were two major upregulated metabolites in ectomycorhizae, which were found formed dense interactions with other metabolites, suggesting their crucial roles in sustaining the metabolic functions in the truffle ectomycorrhization system. This study revealed the effects of truffle-colonization on the metabolites of ectomycorrhiza and illustrates an interactive network between truffles, the host plant, soil and associated microbial communities, shedding light on understanding the ecological effects of truffles.
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Affiliation(s)
- Qiang Li
- Soil and Fertilizer Institute, Sichuan Academy of Agricultural Sciences, Chengdu, China.,Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - Lijuan Yan
- Aquatic Geomicrobiology, Institute of Biodiversity, Friedrich Schiller University Jena, Jena, Germany
| | - Lei Ye
- Soil and Fertilizer Institute, Sichuan Academy of Agricultural Sciences, Chengdu, China
| | - Jie Zhou
- Soil and Fertilizer Institute, Sichuan Academy of Agricultural Sciences, Chengdu, China
| | - Bo Zhang
- Soil and Fertilizer Institute, Sichuan Academy of Agricultural Sciences, Chengdu, China
| | - Weihong Peng
- Soil and Fertilizer Institute, Sichuan Academy of Agricultural Sciences, Chengdu, China
| | - Xiaoping Zhang
- Soil and Fertilizer Institute, Sichuan Academy of Agricultural Sciences, Chengdu, China
| | - Xiaolin Li
- Soil and Fertilizer Institute, Sichuan Academy of Agricultural Sciences, Chengdu, China
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Effects of Field Inoculation with VAM and Bacteria Consortia on Root Growth and Nutrients Uptake in Common Wheat. SUSTAINABILITY 2018. [DOI: 10.3390/su10093286] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
This study investigated the effects of a commercial biofertilizer containing the mycorrhizal fungus Rhizophagus irregularis and the diazotrophic N-fixing bacterium Azotobacter vinelandii on root and shoot growth, yield, and nutrient uptake in common wheat (Triticum aestivum L.) in order to improve the sustainable cultivation of this widespread crop. The trials were carried out in controlled conditions (rhizoboxes) and in open fields over two years to investigate the interaction between inoculation and three doses of nitrogen fertilization (160, 120 and 80 kg ha−1) in a silty-loam soil of the Po Plain (NE Italy). In rhizoboxes, efficient root colonization by R. irregularis was observed at 50 days after sowing with seed inoculation, together with improved root tip density and branching (+~30% vs. controls), while the effects of post-emergence inoculation by soil and foliar spraying were not observable at plant sampling. In the open, field spraying at end tillering significantly increased the volumetric root length density (RLD, +22% vs. controls) and root area density (+18%) after about two months (flowering stage) in both years under medium and high N fertilization doses, but not at the lowest N dose. In absence of inoculation, RLD progressively decreased with increased N doses. Inoculation had a negligible effect on grain yield and N uptake, which followed a typical N dose-response model, while straw Zn, P, and K concentrations were seldom improved. It is concluded that medium-high N fertilization doses are required to achieve the target yield and standards of quality (protein contents) in wheat cultivation, while the use of this mixed VAM-PGPR biofertilizer appears to be a sustainable mean for minimizing the adverse effects of chemical N fertilizers on root expansion and for improving the uptake of low-mobility nutrients, which has potentially relevant environmental benefits.
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Pepe A, Giovannetti M, Sbrana C. Lifespan and functionality of mycorrhizal fungal mycelium are uncoupled from host plant lifespan. Sci Rep 2018; 8:10235. [PMID: 29980700 PMCID: PMC6035242 DOI: 10.1038/s41598-018-28354-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 06/14/2018] [Indexed: 12/31/2022] Open
Abstract
Arbuscular mycorrhizal fungi (AMF) are obligate symbionts, living in associations with the roots of most land plants. AMF produce wide networks of extraradical mycelium (ERM) of indeterminate length, spreading from host roots into the surrounding soil and establishing belowground interconnections among plants belonging to the same or to different taxa. Whether their lifespan and functionality are limited by host plant viability or can be extended beyond this limit is unknown. To address this issue, we performed time-course studies to investigate viability and functionality of ERM produced in an in vivo whole-plant system by Funneliformis mosseae and Rhizoglomus irregulare, after shoot detachment. Our data revealed that viability and functionality of F. mosseae and R. irregulare extraradical hyphae were uncoupled from host plant lifespan. Indeed, ERM spreading from roots of intact or shootless plants showed comparable levels of viability, similar structural traits and ability to establish mycorrhizal symbioses with new plants, as long as five months after shoot removal. Our findings expand the current knowledge on AMF biology and life cycle, providing data on ERM long-term survival in the soil of two Glomeracean species, functional to the prompt establishment of mycorrhizal symbioses and to the maintenance of soil biological fertility.
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Affiliation(s)
- Alessandra Pepe
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, 56124, Italy
| | - Manuela Giovannetti
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, 56124, Italy
| | - Cristiana Sbrana
- CNR-Institute of Agricultural Biology and Biotechnology, UOS Pisa, Pisa, 56124, Italy.
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Berdeni D, Cotton TEA, Daniell TJ, Bidartondo MI, Cameron DD, Evans KL. The Effects of Arbuscular Mycorrhizal Fungal Colonisation on Nutrient Status, Growth, Productivity, and Canker Resistance of Apple ( Malus pumila). Front Microbiol 2018; 9:1461. [PMID: 30018611 PMCID: PMC6037770 DOI: 10.3389/fmicb.2018.01461] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 06/12/2018] [Indexed: 11/24/2022] Open
Abstract
We assess whether arbuscular mycorrhizal fungi (AMF) improve growth, nutritional status, phenology, flower and fruit production, and disease resistance in woody perennial crops using apple (Malus pumila) as a study system. In a fully factorial experiment, young trees were grown for 3 years with or without AMF (Funneliformis mosseae and Rhizophagus irregularis), and with industrial standard fertiliser applications or restricted fertiliser (10% of standard). We use two commercial scions (Dabinett and Michelin) and rootstocks (MM111 and MM106). Industrial standard fertiliser applications reduced AMF colonisation and root biomass, potentially increasing drought sensitivity. Mycorrhizal status was influenced by above ground genotypes (scion type) but not rootstocks, indicating strong interactions between above and below ground plant tissue. The AMF inoculation significantly increased resistance to Neonectria ditissima, a globally economically significant fungal pathogen of apple orchards, but did not consistently alter leaf nutrients, growth, phenology or fruit and flower production. This study significantly advances understanding of AMF benefits to woody perennial crops, especially increased disease resistance which we show is not due to improved tree nutrition or drought alleviation. Breeding programmes and standard management practises can limit the potential for these benefits.
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Affiliation(s)
- Despina Berdeni
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, United Kingdom
| | - T. E. A. Cotton
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, United Kingdom
| | - Tim J. Daniell
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, United Kingdom
- Ecological Sciences, The James Hutton Institute, Dundee, United Kingdom
| | - Martin I. Bidartondo
- Department of Life Sciences, Imperial College London, London, United Kingdom
- Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, Richmond, United Kingdom
| | - Duncan D. Cameron
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, United Kingdom
| | - Karl L. Evans
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, United Kingdom
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Adele NC, Ngwenya BT, Heal KV, Mosselmans JFW. Soil Bacteria Override Speciation Effects on Zinc Phytotoxicity in Zinc-Contaminated Soils. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:3412-3421. [PMID: 29466659 DOI: 10.1021/acs.est.7b05094] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The effects of zinc (Zn) speciation on plant growth in Zn-contaminated soil in the presence of bacteria are unknown but are critical to our understanding of metal biodynamics in the rhizosphere where bacteria are abundant. A 6-week pot experiment investigated the effects of two plant growth promoting bacteria (PGPB), Rhizobium leguminosarum and Pseudomonas brassicacearum, on Zn accumulation and speciation in Brassica juncea grown in soil amended with 600 mg kg-1 elemental Zn as three Zn species: soluble ZnSO4 and nanoparticles of ZnO and ZnS. Measures of plant growth were higher across all Zn treatments inoculated with PGPB compared to uninoculated controls, but Zn species effects were not significant. Transmission electron microscopy identified dense particles in the epidermis and intracellular spaces in roots, suggesting Zn uptake in both dissolved and particulate forms. X-ray absorption near-edge structure (XANES) analysis of roots revealed differences in Zn speciation between treatments. Uninoculated plants exposed to ZnSO4 contained Zn predominantly in the form of Zn phytate (35%) and Zn polygalacturonate (30%), whereas Zn cysteine (57%) and Zn polygalacturonate (37%) dominated in roots exposed to ZnO nanoparticles. Inoculation with PGPB increased (>50%) the proportion of Zn cysteine under all Zn treatments, suggesting Zn coordination with cysteine as the predominant mechanism of Zn toxicity reduction by PGPB. Using this approach, we show, for the first time, that although speciation is important, the presence of rhizospheric bacteria completely overrides speciation effects such that most of the Zn in plant tissue exists as complexes other than the original form.
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Affiliation(s)
- Nyekachi C Adele
- School of GeoSciences , University of Edinburgh , Edinburgh , U.K
| | - Bryne T Ngwenya
- School of GeoSciences , University of Edinburgh , Edinburgh , U.K
| | - Kate V Heal
- School of GeoSciences , University of Edinburgh , Edinburgh , U.K
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