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Fortune JA, Bingol E, Qi A, Baker D, Ritchie F, Karandeni Dewage CS, Fitt BDL, Huang YJ. Leptosphaeria biglobosa inhibits the production of sirodesmin PL by L. maculans. PEST MANAGEMENT SCIENCE 2024; 80:2416-2425. [PMID: 36327145 DOI: 10.1002/ps.7275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 10/31/2022] [Accepted: 11/03/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND Phoma stem canker is caused by two coexisting pathogens, Leptosphaeria maculans and L. biglobosa. They coexist because of their temporal and spatial separations, which are associated with the differences in timing of their ascospore release. L. maculans produces sirodesmin PL, while L. biglobosa does not. However, their interaction/coexistence in terms of secondary metabolite production is not understood. RESULTS Secondary metabolites were extracted from liquid cultures, L. maculans only (Lm only), L. biglobosa only (Lb only), L. maculans and L. biglobosa simultaneously (Lm&Lb) or sequentially 7 days later (Lm+Lb). Sirodesmin PL or its precursors were identified in extracts from 'Lm only' and 'Lm+Lb', but not from 'Lm&Lb'. Metabolites from 'Lb only', 'Lm&Lb' or 'Lm+Lb' caused significant reductions in L. maculans colony area. However, only the metabolites containing sirodesmin PL caused a significant reduction to L. biglobosa colony area. When oilseed rape cotyledons were inoculated with conidia of 'Lm only', 'Lb only' or 'Lm&Lb', 'Lm only' produced large gray lesions, while 'Lm&Lb' produced small dark lesions similar to lesions caused by 'Lb only'. Sirodesmin PL was found only in the plant extracts from 'Lm only'. These results suggest that L. biglobosa prevents the production of sirodesmin PL and its precursors by L. maculans when they grow simultaneously in vitro or in planta. CONCLUSION For the first time, L. biglobosa has been shown to inhibit the production of sirodesmin PL by L. maculans when interacting simultaneously with L. maculans either in vitro or in planta. This antagonistic effect of interspecific interaction may affect their coexistence and subsequent disease progression and management. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- James A Fortune
- Centre for Agriculture, Food and Environmental Management Research, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK
- Disease and Pest Management, ADAS Boxworth, Cambridge, UK
| | - Evren Bingol
- Centre for Agriculture, Food and Environmental Management Research, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK
| | - Aiming Qi
- Centre for Agriculture, Food and Environmental Management Research, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK
| | - Daniel Baker
- Centre for Topical Drug Delivery and Toxicology, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK
| | - Faye Ritchie
- Disease and Pest Management, ADAS Boxworth, Cambridge, UK
| | - Chinthani S Karandeni Dewage
- Centre for Agriculture, Food and Environmental Management Research, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK
| | - Bruce D L Fitt
- Centre for Agriculture, Food and Environmental Management Research, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK
| | - Yong-Ju Huang
- Centre for Agriculture, Food and Environmental Management Research, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK
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2
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Bogar LM. Modified source-sink dynamics govern resource exchange in ectomycorrhizal symbiosis. THE NEW PHYTOLOGIST 2024; 242:1523-1528. [PMID: 37691279 DOI: 10.1111/nph.19259] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 08/16/2023] [Indexed: 09/12/2023]
Abstract
Ectomycorrhizal symbiosis between roots and fungi is founded on the movement of carbon from plants to fungi, and of soil resources from fungi to plants. Framing this movement as a trade can facilitate an understanding of how this mutualism has developed over evolutionary time, but fails to explain experimental observations of carbon and nutrient movement. Here, I propose that source-sink dynamics are an essential basic model to explain the movement of plant and fungal resources, which may be modified by plant immune response, variability in fungal molecular repertoires, and competition in the soil. Source-sink dynamics provide testable hypotheses to illuminate mechanisms of ectomycorrhizal resource movement and its consequences for mutualism stability and forest function under climate change.
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Affiliation(s)
- Laura M Bogar
- Department of Plant Biology, University of California, Davis, 605 Hutchison Dr., Davis, CA, 95616, USA
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3
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Wei H, Zhong Z, Li Z, Zhang Y, Stukenbrock EH, Tang B, Yang N, Baroncelli R, Peng L, Liu Z, He X, Yang Y, Yuan Z. Loss of the accessory chromosome converts a pathogenic tree-root fungus into a mutualistic endophyte. PLANT COMMUNICATIONS 2024; 5:100672. [PMID: 37563834 PMCID: PMC10811371 DOI: 10.1016/j.xplc.2023.100672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 06/01/2023] [Accepted: 08/04/2023] [Indexed: 08/12/2023]
Abstract
Some fungal accessory chromosomes (ACs) may contribute to virulence in plants. However, the mechanisms by which ACs determine specific traits associated with lifestyle transitions along a symbiotic continuum are not clear. Here we delineated the genetic divergence in two sympatric but considerably variable isolates (16B and 16W) of the poplar-associated fungus Stagonosporopsis rhizophilae. We identified a ∼0.6-Mb horizontally acquired AC in 16W that resulted in a mildly parasitic lifestyle in plants. Complete deletion of the AC (Δ16W) significantly altered the fungal phenotype. Specifically, Δ16W was morphologically more similar to 16B, showed enhanced melanization, and established beneficial interactions with poplar plants, thereby acting as a dark septate endophyte. RNA sequencing (RNA-seq) analysis showed that AC loss induced the upregulation of genes related to root colonization and biosynthesis of indole acetic acid and melanin. We observed that the AC maintained a more open status of chromatin across the genome, indicating an impressive remodeling of cis-regulatory elements upon AC loss, which potentially enhanced symbiotic effectiveness. We demonstrated that the symbiotic capacities were non-host-specific through comparable experiments on Triticum- and Arabidopsis-fungus associations. Furthermore, the three isolates generated symbiotic interactions with a nonvascular liverwort. In summary, our study suggests that the AC is a suppressor of symbiosis and provides insights into the underlying mechanisms of mutualism with vascular plants in the absence of traits encoded by the AC. We speculate that AC-situated effectors and other potential secreted molecules may have evolved to specifically target vascular plants and promote mild virulence.
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Affiliation(s)
- Huanshen Wei
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing 100091, China; Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China
| | - Zhenhui Zhong
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Zhongfeng Li
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing 100091, China; Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China
| | - Yuwei Zhang
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing 100091, China; Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China
| | - Eva H Stukenbrock
- Environmental Genomics, Christian-Albrechts University, 24118 Kiel, Germany; Max Planck Fellow Group Environmental Genomics, Max Planck Institute for Evolutionary Biology, 24306 Plön, Germany.
| | - Boping Tang
- Jiangsu Key Laboratory for Bioresources of Saline Soils, School of Wetlands, Yancheng Teachers University, Yancheng 224002, China
| | - Ningning Yang
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing 100091, China; Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China
| | - Riccardo Baroncelli
- Department of Agricultural and Food Sciences (DISTAL), University of Bologna, 40127 Bologna, Italy
| | - Long Peng
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing 100091, China; Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China
| | - Zhuo Liu
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing 100091, China; Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China
| | - Xinghua He
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing 100091, China; Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China
| | - Yuzhan Yang
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing 100091, China; Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China
| | - Zhilin Yuan
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing 100091, China; Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China.
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4
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Smith AH, Bogar LM, Moeller HV. Fungal Fight Club: phylogeny and growth rate predict competitive outcomes among ectomycorrhizal fungi. FEMS Microbiol Ecol 2023; 99:fiad108. [PMID: 37697652 PMCID: PMC10516346 DOI: 10.1093/femsec/fiad108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 09/01/2023] [Accepted: 09/07/2023] [Indexed: 09/13/2023] Open
Abstract
Ectomycorrhizal fungi are among the most prevalent fungal partners of plants and can constitute up to one-third of forest microbial biomass. As mutualistic partners that supply nutrients, water, and pathogen defense, these fungi impact host plant health and biogeochemical cycling. Ectomycorrhizal fungi are also extremely diverse, and the community of fungal partners on a single plant host can consist of dozens of individuals. However, the factors that govern competition and coexistence within these communities are still poorly understood. In this study, we used in vitro competitive assays between five ectomycorrhizal fungal strains to examine how competition and pH affect fungal growth. We also tested the ability of evolutionary history to predict the outcomes of fungal competition. We found that the effects of pH and competition on fungal performance varied extensively, with changes in growth media pH sometimes reversing competitive outcomes. Furthermore, when comparing the use of phylogenetic distance and growth rate in predicting competitive outcomes, we found that both methods worked equally well. Our study further highlights the complexity of ectomycorrhizal fungal competition and the importance of considering phylogenetic distance, ecologically relevant traits, and environmental conditions in predicting the outcomes of these interactions.
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Affiliation(s)
- Alexander H Smith
- Department of Integrative Biology, University of Colorado, Denver Auraria Campus Science Building 1150 12th St, Denver CO 80204, USA
| | - Laura M Bogar
- Department of Plant Biology, University of California, Davis, 605 Hutchison Dr Green Hall rm 1002 Davis CA 95616-5720, USA
| | - Holly V Moeller
- Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara CA 93106-9620, USA
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5
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van 't Padje A, Klein M, Caldas V, Oyarte Galvez L, Broersma C, Hoebe N, Sanders IR, Shimizu T, Kiers ET. Decreasing relatedness among mycorrhizal fungi in a shared plant network increases fungal network size but not plant benefit. Ecol Lett 2021; 25:509-520. [PMID: 34971476 PMCID: PMC9305232 DOI: 10.1111/ele.13947] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/03/2021] [Accepted: 11/17/2021] [Indexed: 11/28/2022]
Abstract
Theory suggests that relatives will cooperate more, and compete less, because of an increased benefit for shared genes. In symbiotic partnerships, hosts may benefit from interacting with highly related symbionts because there is less conflict among the symbionts. This has been difficult to test empirically. We used the arbuscular mycorrhizal symbiosis to study the effects of fungal relatedness on host and fungal benefits, creating fungal networks varying in relatedness between two hosts, both in soil and in‐vitro. To determine how fungal relatedness affected overall transfer of nutrients, we fluorescently tagged phosphorus and quantified resource distribution between two root systems. We found that colonization by less‐related fungi was associated with increased fungal growth, lower transport of nutrients across the network, and lower plant benefit ‐ likely an outcome of increased fungal competition. More generally, we demonstrate how symbiont relatedness can mediate benefits of symbioses.
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Affiliation(s)
- Anouk van 't Padje
- Laboratory of Genetics, Wageningen University & Research, Wageningen, the Netherlands.,Department of Ecological Sciences, Faculty of Earth and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Malin Klein
- Laboratory of Genetics, Wageningen University & Research, Wageningen, the Netherlands
| | - Victor Caldas
- Department of Ecological Sciences, Faculty of Earth and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands.,AMOLF Institute, Amsterdam, the Netherlands
| | - Loreto Oyarte Galvez
- Department of Ecological Sciences, Faculty of Earth and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands.,AMOLF Institute, Amsterdam, the Netherlands
| | - Cathleen Broersma
- Department of Ecological Sciences, Faculty of Earth and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Nicky Hoebe
- Department of Ecological Sciences, Faculty of Earth and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Ian R Sanders
- Departent of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | | | - E Toby Kiers
- Department of Ecological Sciences, Faculty of Earth and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
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6
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Szymczak A, Ryo M, Roy J, Rillig MC. Diversity of Growth Responses of Soil Saprobic Fungi to Recurring Heat Events. Front Microbiol 2020; 11:1326. [PMID: 32636822 PMCID: PMC7316893 DOI: 10.3389/fmicb.2020.01326] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 05/25/2020] [Indexed: 01/04/2023] Open
Abstract
As a consequence of ongoing climate change, the frequency of extreme heat events is expected to increase. Recurring heat pulses may disrupt functions supported by soil microorganisms, thus affecting the entire ecosystem. However, most perturbation experiments only test effects of single heat events, and therefore it remains largely unknown how soil microorganisms react to repeated pulse events. Here we present data from a lab experiment exposing 32 filamentous fungi, originally isolated from the same soil, to sequential heat perturbations. Soil saprobic fungi isolates were exposed to one or two heat pulses: mild (35°C/2 h), strong (45°C/1 h), or both in sequence (35°C/2 h+45°C/1 h), and we assessed growth rate. Out of the 32 isolates 13 isolates showed an antagonistic response, 3 isolates a synergistic response and 16 isolates responded in an additive manner. Thus the 32 filamentous fungal isolates used here showed the full range of possible responses to an identical heat perturbation sequence. This diversity of responses could have consequences for soil-borne ecosystem services, highlighting the potential importance of fungal biodiversity in maintaining such services, particularly in the context of climate change.
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Affiliation(s)
- Aleksandra Szymczak
- Institute of Biology, Freie Universität Berlin, Berlin, Germany
- Berlin-Brandenburg Institute of Advanced Biodiversity Research, Berlin, Germany
| | - Masahiro Ryo
- Institute of Biology, Freie Universität Berlin, Berlin, Germany
- Berlin-Brandenburg Institute of Advanced Biodiversity Research, Berlin, Germany
| | - Julien Roy
- Institute of Biology, Freie Universität Berlin, Berlin, Germany
- Berlin-Brandenburg Institute of Advanced Biodiversity Research, Berlin, Germany
| | - Matthias C. Rillig
- Institute of Biology, Freie Universität Berlin, Berlin, Germany
- Berlin-Brandenburg Institute of Advanced Biodiversity Research, Berlin, Germany
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7
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Bennett AE, Classen AT. Climate change influences mycorrhizal fungal-plant interactions, but conclusions are limited by geographical study bias. Ecology 2020; 101:e02978. [PMID: 31953955 DOI: 10.1002/ecy.2978] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 11/22/2019] [Accepted: 12/05/2019] [Indexed: 12/22/2022]
Abstract
Climate change is altering the interactions among plants and soil organisms in ways that will alter the structure and function of ecosystems. We reviewed the literature and developed a map of studies focused on how the three most common types of mycorrhizal fungi (arbuscular mycorrhizal [AM], ectomycorrhizal [EcM], and ericoid mycorrhizal [ErM] fungi) respond to elevated atmospheric carbon dioxide concentrations (eCO2 ), climatic warming, and changes in the distribution of precipitation. Broadly, we ask how do mycorrhizal fungi respond to climate change, how do these responses vary by fungal type, and how do mycorrhizal traits influence plant adaptation, movement, or extinction in response to climatic change? First, we found that 92% of studies were conducted in the northern hemisphere, and plant host, ecosystem type and study location were only correlated with each other in the northern hemisphere because studies across all mycorrhizal fungal types were only common in the northern hemisphere. Second, we show that temperature and rainfall variability had more variable effects than eCO2 on mycorrhizal fungal structures, but these effects were context dependent. Third, while mycorrhizal fungal types vary in their responses to climate change, it appears that warming leads to more variable responses in ectomycorrhizal than in arbuscular mycorrhizal fungi. Finally, we discuss common traits of mycorrhizal fungi that could aid in fungal and plant adaption to climate change. We posit that mycorrhizal fungi can buffer plant hosts against extinction risk, they can facilitate or retard the dispersal success of plants moving away from poor environments, and, by buffering host plants, they can enable host plant adaptation to new climates. All of these influences are, however, context dependent a finding that reflects the complex traits of mycorrhizal fungi as a group, the diversity of plant species they associate with and the variation in ecosystems in which they reside. Overall, while we point out many gaps in our understanding of the influence of climate changes on mycorrhizal fungi, we also highlight the large number of opportunities for researching plant and mycorrhizal fungal responses to and mitigation of climate changes.
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Affiliation(s)
- Alison E Bennett
- Department of Evolution, Ecology and Organismal Biology, Ohio State University, Columbus, Ohio, 43210, USA
| | - Aimée T Classen
- Rubenstein School of Environment & Natural Resources, University of Vermont, Burlington, Vermont, 05405, USA.,The Gund Institute for Environment, University of Vermont, Burlington, Vermont, 05405, USA.,Center for Macroecology, Evolution and Climate, The Natural History Museum of Denmark, University of Copenhagen, Copenhagen Ø, DK-2100, Denmark
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8
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Mucha J, Peay KG, Smith DP, Reich PB, Stefański A, Hobbie SE. Effect of Simulated Climate Warming on the Ectomycorrhizal Fungal Community of Boreal and Temperate Host Species Growing Near Their Shared Ecotonal Range Limits. MICROBIAL ECOLOGY 2018; 75:348-363. [PMID: 28741266 PMCID: PMC5742605 DOI: 10.1007/s00248-017-1044-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 07/13/2017] [Indexed: 05/05/2023]
Abstract
Ectomycorrhizal (ECM) fungi can influence the establishment and performance of host species by increasing nutrient and water absorption. Therefore, understanding the response of ECM fungi to expected changes in the global climate is crucial for predicting potential changes in the composition and productivity of forests. While anthropogenic activity has, and will continue to, cause global temperature increases, few studies have investigated how increases in temperature will affect the community composition of ectomycorrhizal fungi. The effects of global warming are expected to be particularly strong at biome boundaries and in the northern latitudes. In the present study, we analyzed the effects of experimental manipulations of temperature and canopy structure (open vs. closed) on ectomycorrhizal fungi identified from roots of host seedlings through 454 pyrosequencing. The ecotonal boundary site selected for the study was between the southern boreal and temperate forests in northern Minnesota, USA, which is the southern limit range for Picea glauca and Betula papyrifera and the northern one for Pinus strobus and Quercus rubra. Manipulations that increased air and soil temperature by 1.7 and 3.4 °C above ambient temperatures, respectively, did not change ECM richness but did alter the composition of the ECM community in a manner dependent on host and canopy structure. The prediction that colonization of boreal tree species with ECM symbionts characteristic of temperate species would occur was not substantiated. Overall, only a small proportion of the ECM community appears to be strongly sensitive to warming.
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Affiliation(s)
- Joanna Mucha
- Institute of Dendrology, Polish Academy of Sciences, Kórnik, Poland.
| | - Kabir G Peay
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
| | - Dylan P Smith
- University of California, California Institute for Quantitative Biosciences, Berkeley, CA, USA
| | - Peter B Reich
- Department of Forest Resources, University of Minnesota, St. Paul, MN, USA
- Western Sydney University, Hawkesbury Institute for the Environment, Penrith, NSW, Australia
| | - Artur Stefański
- Department of Forest Resources, University of Minnesota, St. Paul, MN, USA
| | - Sarah E Hobbie
- Department of Ecology, Evolution and Behavior, University of Minnesota, St. Paul, MN, USA
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9
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Role of plant-fungal nutrient trading and host control in determining the competitive success of ectomycorrhizal fungi. ISME JOURNAL 2017; 11:2666-2676. [PMID: 28731478 DOI: 10.1038/ismej.2017.116] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 05/04/2017] [Accepted: 06/04/2017] [Indexed: 11/08/2022]
Abstract
Multiple ectomycorrhizal fungi (EMF) compete to colonise the roots of a host plant, but it is not known whether their success is under plant or fungal control, or a combination of both. We assessed whether plants control EMF colonisation by preferentially allocating more carbon to more beneficial partners in terms of nitrogen supply or if other factors drive competitive success. We combined stable isotope labelling and RNA-sequencing approaches to characterise nutrient exchange between the plant host Eucalyptus grandis and three Pisolithus isolates when growing alone and when competing either indirectly (with a physical barrier) or directly. Overall, we found that nitrogen provision to the plant does not explain the amount of carbon that an isolate receives nor the number of roots that it colonises. Differences in nutrient exchange among isolates were related to differences in expression of key fungal and plant nitrogen and carbon transporter genes. When given a choice of partners, the plant was able to limit colonisation by the least cooperative isolate. This was not explained by a reduction in allocated carbon. Instead, our results suggest that partner choice in EMF could operate through the upregulation of defence-related genes against those fungi providing fewer nutrients.
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10
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Bauman D, Raspé O, Meerts P, Degreef J, Ilunga Muledi J, Drouet T. Multiscale assemblage of an ectomycorrhizal fungal community: the influence of host functional traits and soil properties in a 10-ha miombo forest. FEMS Microbiol Ecol 2016; 92:fiw151. [PMID: 27402715 DOI: 10.1093/femsec/fiw151] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/04/2016] [Indexed: 11/14/2022] Open
Abstract
Ectomycorrhizal fungi (EMF) are highly diversified and dominant in a number of forest ecosystems. Nevertheless, their scales of spatial distribution and the underlying ecological processes remain poorly understood. Although most EMF are considered to be generalists regarding host identity, a preference toward functional strategies of host trees has never been tested. Here, the EMF community was characterised by DNA sequencing in a 10-ha tropical dry season forest-referred to as miombo-an understudied ecosystem from a mycorrhizal perspective. We used 36 soil parameters and 21 host functional traits (FTs) as candidate explanatory variables in spatial constrained ordinations for explaining the EMF community assemblage. Results highlighted that the community variability was explained by host FTs related to the 'leaf economics spectrum' (adjusted R(2) = 11%; SLA, leaf area, foliar Mg content), and by soil parameters (adjusted R(2) = 17%), notably total forms of micronutrients or correlated available elements (Al, N, K, P). Both FTs and soil generated patterns in the community at scales ranging from 75 to 375 m. Our results indicate that soil is more important than previously thought for EMF in miombo woodlands, and show that FTs of host species can be better predictors of symbiont distribution than taxonomical identity.
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Affiliation(s)
- David Bauman
- Laboratoire d'Écologie Végétale et Biogéochimie, Université Libre de Bruxelles, 50 av. F. D. Roosevelt, CP 244, 1050 Brussels, Belgium
| | - Olivier Raspé
- Department of Bryophyta and Thallophyta, Botanic Garden Meise, 38 Nieuwlaan, B-1860 Meise, Belgium Fédération Wallonie-Bruxelles, Direction Générale de l'Enseignement non obligatoire et de la Recherche scientifique, Rue A. Lavallée 1, 1080 Brussels, Belgium
| | - Pierre Meerts
- Laboratoire d'Écologie Végétale et Biogéochimie, Université Libre de Bruxelles, 50 av. F. D. Roosevelt, CP 244, 1050 Brussels, Belgium
| | - Jérôme Degreef
- Department of Bryophyta and Thallophyta, Botanic Garden Meise, 38 Nieuwlaan, B-1860 Meise, Belgium Fédération Wallonie-Bruxelles, Direction Générale de l'Enseignement non obligatoire et de la Recherche scientifique, Rue A. Lavallée 1, 1080 Brussels, Belgium
| | - Jonathan Ilunga Muledi
- Faculté des Sciences agronomiques, Université de Lubumbashi, Route Kasapa, BP 1825 Lubumbashi, The Democratic Republic of the Congo
| | - Thomas Drouet
- Laboratoire d'Écologie Végétale et Biogéochimie, Université Libre de Bruxelles, 50 av. F. D. Roosevelt, CP 244, 1050 Brussels, Belgium
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