1
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F K, L B, M EM, M R B, N F, R B, F B, A DS, C D, M N F, G G, M J G, M L, A L, W L M, A N, A S, G S, E I V, K V, L V, B Z, L A, D D, M B. "Ectomycorrhizal exploration type" could be a functional trait explaining the spatial distribution of tree symbiotic fungi as a function of forest humus forms. MYCORRHIZA 2024; 34:203-216. [PMID: 38700516 DOI: 10.1007/s00572-024-01146-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 04/15/2024] [Indexed: 06/12/2024]
Abstract
In European forests, most tree species form symbioses with ectomycorrhizal (EM) and arbuscular mycorrhizal (AM) fungi. The EM fungi are classified into different morphological types based on the development and structure of their extraradical mycelium. These structures could be root extensions that help trees to acquire nutrients. However, the relationship between these morphological traits and functions involved in soil nutrient foraging is still under debate.We described the composition of mycorrhizal fungal communities under 23 tree species in a wide range of climates and humus forms in Europe and investigated the exploratory types of EM fungi. We assessed the response of this tree extended phenotype to humus forms, as an indicator of the functioning and quality of forest soils. We found a significant relationship between the relative proportion of the two broad categories of EM exploration types (short- or long-distance) and the humus form, showing a greater proportion of long-distance types in the least dynamic soils. As past land-use and host tree species are significant factors structuring fungal communities, we showed this relationship was modulated by host trait (gymnosperms versus angiosperms), soil depth and past land use (farmland or forest).We propose that this potential functional trait of EM fungi be used in future studies to improve predictive models of forest soil functioning and tree adaptation to environmental nutrient conditions.
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Affiliation(s)
- Khalfallah F
- Université de Lorraine, INRAE, IAM, Nancy, F-54000, France
- INRAE, BEF, Nancy, F-54000, France
| | - Bon L
- INRAE, ISPA, Bordeaux Sciences Agro, Villenave d'Ornon, F-33140, France
| | - El Mazlouzi M
- INRAE, ISPA, Bordeaux Sciences Agro, Villenave d'Ornon, F-33140, France
- IEES, Université Paris Est Créteil, CNRS, INRAE, IRD, Créteil, 94010, 94010, France
| | - Bakker M R
- INRAE, ISPA, Bordeaux Sciences Agro, Villenave d'Ornon, F-33140, France
| | - Fanin N
- INRAE, ISPA, Bordeaux Sciences Agro, Villenave d'Ornon, F-33140, France
| | - Bellanger R
- INRAE, Site de la Villa Thuret, Antibes, 1353 UEVT, 06600, France
| | - Bernier F
- INRAE, Domaine de l'Hermitage, Cestas Pierroton, 0570 UEFP, 33610, France
| | - De Schrijver A
- Departement Biowetenschappen en Industriële Technologie, AgroFoodNature HOGENT, Melle, 9090, Belgium
| | - Ducatillon C
- INRAE, Site de la Villa Thuret, Antibes, 1353 UEVT, 06600, France
| | - Fotelli M N
- Forest Research Institute Hellenic Agricultural Organization Dimitra, Vassilika, Thessaloniki, 57006, Greece
| | - Gateble G
- INRAE, Site de la Villa Thuret, Antibes, 1353 UEVT, 06600, France
| | - Gundale M J
- Department of Forest Ecology and Management, Swedish Univ. of Agricultural Sciences, Umeå, 901-83, Sweden
| | - Larsson M
- Department of Forest Ecology and Management, Swedish Univ. of Agricultural Sciences, Umeå, 901-83, Sweden
| | - Legout A
- INRAE, BEF, Nancy, F-54000, France
| | - Mason W L
- Forest Research, Northern Research Station, Roslin, Midlothian, EH25 9SY, Scotland, UK
| | - Nordin A
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Centre (UPSC), Swedish University of Agricultural Sciences, Umeå, 901-83, Sweden
| | - Smolander A
- Natural Resources Institute Finland (Luke), Latokartanonkaari 9, Helsinki, 00790, Finland
| | - Spyroglou G
- Forest Research Institute Hellenic Agricultural Organization Dimitra, Vassilika, Thessaloniki, 57006, Greece
| | - Vanguelova E I
- Forest Research, Alice Holt, Alice Holt Lodge, Farnham, GU10 4LH, UK
| | - Verheyen K
- Forest & Nature Lab, Ghent University, Gontrode, Melle, 9090, Belgium
| | - Vesterdal L
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg C, 1958, Denmark
| | - Zeller B
- INRAE, BEF, Nancy, F-54000, France
| | - Augusto L
- INRAE, ISPA, Bordeaux Sciences Agro, Villenave d'Ornon, F-33140, France.
| | | | - Buée M
- Université de Lorraine, INRAE, IAM, Nancy, F-54000, France.
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2
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Michaud TJ, Cline LC, Hobbie EA, Gutknecht JLM, Kennedy PG. Herbarium specimens reveal that mycorrhizal type does not mediate declining temperate tree nitrogen status over a century of environmental change. THE NEW PHYTOLOGIST 2024; 242:1717-1724. [PMID: 38073143 DOI: 10.1111/nph.19452] [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: 10/06/2023] [Accepted: 10/27/2023] [Indexed: 04/26/2024]
Abstract
Rising atmospheric carbon dioxide concentrations (CO2) and atmospheric nitrogen (N) deposition have contrasting effects on ectomycorrhizal (EM) and arbuscular mycorrhizal (AM) symbioses, potentially mediating forest responses to environmental change. In this study, we evaluated the cumulative effects of historical environmental change on N concentrations and δ15N values in AM plants, EM plants, EM fungi, and saprotrophic fungi using herbarium specimens collected in Minnesota, USA from 1871 to 2016. To better understand mycorrhizal mediation of foliar δ15N, we also analyzed a subset of previously published foliar δ15N values from across the United States to parse the effects of N deposition and CO2 rise. Over the last century in Minnesota, N concentrations declined among all groups except saprotrophic fungi. δ15N also declined among all groups of plants and fungi; however, foliar δ15N declined less in EM plants than in AM plants. In the analysis of previously published foliar δ15N values, this slope difference between EM and AM plants was better explained by nitrogen deposition than by CO2 rise. Mycorrhizal type did not explain trajectories of plant N concentrations. Instead, plants and EM fungi exhibited similar declines in N concentrations, consistent with declining forest N status despite moderate levels of N deposition.
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Affiliation(s)
- Talia J Michaud
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, 55108, USA
| | | | - Erik A Hobbie
- Earth Systems Research Center, University of New Hampshire, Durham, NH, 03824, USA
| | - Jessica L M Gutknecht
- Department of Soil, Water, and Climate, University of Minnesota, St Paul, MN, 55108, USA
| | - Peter G Kennedy
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, 55108, USA
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3
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Hupperts SF, Islam KS, Gundale MJ, Kardol P, Sundqvist MK. Warming influences carbon and nitrogen assimilation between a widespread Ericaceous shrub and root-associated fungi. THE NEW PHYTOLOGIST 2024; 241:1062-1073. [PMID: 37950517 DOI: 10.1111/nph.19384] [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: 09/07/2023] [Accepted: 10/19/2023] [Indexed: 11/12/2023]
Abstract
High-latitude ecosystems are warming faster than other biomes and are often dominated by a ground layer of Ericaceous shrubs, which can respond positively to warming. The carbon-for-nitrogen (C-for-N) exchange between Ericaceous shrubs and root-associated fungi may underlie shrub responses to warming, but has been understudied. In a glasshouse setting, we examined the effects of warming on the C-for-N exchange between the Ericaceous shrub Empetrum nigrum ssp. hermaphroditum and its root-associated fungi. We applied different 13 C and 15 N isotope labels, including a simple organic N form (glycine) and a complex organic N form (moss litter) and quantified their assimilation into soil, plant biomass, and root fungal biomass pools. We found that warming lowered the amount of 13 C partitioned to root-associated fungi per unit of glycine 15 N assimilated by E. nigrum, but only in the short term. By contrast, warming increased the amount of 13 C partitioned to root-associated fungi per unit of moss 15 N assimilated by E. nigrum. Our study suggests that climate warming affects the short-term exchange of C and N between a widespread Ericaceous shrub and root-associated fungi. Furthermore, while most isotope tracing studies use labile N sources, we demonstrate that a ubiquitous recalcitrant N source may produce contrasting results.
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Affiliation(s)
- Stefan F Hupperts
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, 901 83, Sweden
| | - Kazi Samiul Islam
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, 901 83, Sweden
| | - Michael J Gundale
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, 901 83, Sweden
| | - Paul Kardol
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, 901 83, Sweden
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences (SLU), Uppsala, 750 07, Sweden
| | - Maja K Sundqvist
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, 901 83, Sweden
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Liu B, Fan X, Meng D, Liu Z, Gao D, Chang Q, Bai E. Ectomycorrhizal trees rely on nitrogen resorption less than arbuscular mycorrhizal trees globally. Ecol Lett 2024; 27:e14346. [PMID: 38009408 DOI: 10.1111/ele.14346] [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: 04/11/2023] [Revised: 10/31/2023] [Accepted: 11/04/2023] [Indexed: 11/28/2023]
Abstract
Nitrogen (N) resorption is an important pathway of N conservation, contributing to an important proportion of plant N requirement. However, whether the ratio of N resorption to N requirement may be affected by environmental factors, mycorrhizal types or atmospheric CO2 concentration remains unclear. Here, we conducted a meta-analysis on the impacts of environmental factors and mycorrhizal types on this ratio. We found this ratio in ectomycorrhizal (EM) trees decreased with mean annual precipitation, mean annual temperature, soil total N content and atmospheric CO2 concentration and was significantly lower than that in arbuscular mycorrhizal (AM) trees. An in situ 15 N tracing experiment further confirmed that AM trees have a stronger reliance on N resorption than EM trees. Our study suggests that AM and EM trees potentially have different strategies for alleviation of progressive N limitation, highlighting the necessity of incorporating plant mycorrhizal types into Earth System Models.
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Affiliation(s)
- Bai Liu
- Key Laboratory of Geographical Processes and Ecological Security of Changbai Mountains, Ministry of Education; School of Geographical Sciences, Northeast Normal University, Changchun, China
| | - Xianlei Fan
- Key Laboratory of Geographical Processes and Ecological Security of Changbai Mountains, Ministry of Education; School of Geographical Sciences, Northeast Normal University, Changchun, China
| | - Di Meng
- Key Laboratory of Geographical Processes and Ecological Security of Changbai Mountains, Ministry of Education; School of Geographical Sciences, Northeast Normal University, Changchun, China
| | - Ziping Liu
- Key Laboratory of Geographical Processes and Ecological Security of Changbai Mountains, Ministry of Education; School of Geographical Sciences, Northeast Normal University, Changchun, China
- Key Laboratory of Vegetation Ecology, Ministry of Education, Northeast Normal University, Changchun, China
| | - Decai Gao
- Key Laboratory of Geographical Processes and Ecological Security of Changbai Mountains, Ministry of Education; School of Geographical Sciences, Northeast Normal University, Changchun, China
- Key Laboratory of Vegetation Ecology, Ministry of Education, Northeast Normal University, Changchun, China
| | - Qing Chang
- Key Laboratory of Geographical Processes and Ecological Security of Changbai Mountains, Ministry of Education; School of Geographical Sciences, Northeast Normal University, Changchun, China
- Key Laboratory of Vegetation Ecology, Ministry of Education, Northeast Normal University, Changchun, China
| | - Edith Bai
- Key Laboratory of Geographical Processes and Ecological Security of Changbai Mountains, Ministry of Education; School of Geographical Sciences, Northeast Normal University, Changchun, China
- Key Laboratory of Vegetation Ecology, Ministry of Education, Northeast Normal University, Changchun, China
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5
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Xia A, Wu Y, Xiang J, Yin H, Ming J, Qin Z. Quantification of Glucose Metabolism and Nitrogen Utilization in Two Brassicaceae Species under Bicarbonate and Variable Ammonium Soil Conditions. PLANTS (BASEL, SWITZERLAND) 2023; 12:3095. [PMID: 37687342 PMCID: PMC10489622 DOI: 10.3390/plants12173095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Revised: 08/15/2023] [Accepted: 08/25/2023] [Indexed: 09/10/2023]
Abstract
In karst habitats under drought conditions, high bicarbonate (high pH), and an abundant nitrate soil environment, bicarbonate regulates the glycolysis (EMP) and pentose phosphate pathways (PPP), which distribute ATP and NADPH, affecting nitrate (NO3-) and ammonium (NH4+) utilization in plants. However, the relationship between EMP PPP and NO3-, and NH4+ utilization and their responses to bicarbonate and variable ammonium still remains elusive. In this study, we used Brassica napus (Bn, a non-karst-adaptable plant) and Orychophragmus violaceus (Ov, a karst-adaptable plant) as plant materials, employed a bidirectional nitrogen-isotope-tracing method, and performed the quantification of the contribution of EMP and PPP. We found that bicarbonate and ammonium inhibited glucose metabolism and nitrogen utilization in Bn under simulated karst habitats. On the other hand, it resulted in a shift from EMP to PPP to promote ammonium utilization in Ov under high ammonium stress in karst habitats. Compared with Bn, bicarbonate promoted glucose metabolism and nitrogen utilization in Ov at low ammonium levels, leading to an increase in photosynthesis, the PPP, carbon and nitrogen metabolizing enzyme activities, nitrate/ammonium utilization, and total inorganic nitrogen assimilation capacity. Moreover, bicarbonate significantly reduced the growth inhibition of Ov by high ammonium, resulting in an improved PPP, RCRUBP, and ammonium utilization to maintain growth. Quantifying the relationships between EMP, PPP, NO3-, and NH4+ utilization can aid the accurate analysis of carbon and nitrogen use efficiency changes in plant species. Therefore, it provides a new prospect to optimize the nitrate/ammonium utilization in plants and further reveals the differential responses of inorganic carbon and nitrogen (C-N) metabolism to bicarbonate and variable ammonium in karst habitats.
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Affiliation(s)
- Antong Xia
- Enshi Tujia & Miao Autonomous Prefecture Academy of Agricultural Sciences, Enshi 445000, China; (A.X.)
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Yanyou Wu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Jiqian Xiang
- Enshi Tujia & Miao Autonomous Prefecture Academy of Agricultural Sciences, Enshi 445000, China; (A.X.)
| | - Hongqing Yin
- Enshi Tujia & Miao Autonomous Prefecture Academy of Agricultural Sciences, Enshi 445000, China; (A.X.)
| | - Jiajia Ming
- Enshi Tujia & Miao Autonomous Prefecture Academy of Agricultural Sciences, Enshi 445000, China; (A.X.)
| | - Zhanghui Qin
- Enshi Tujia & Miao Autonomous Prefecture Academy of Agricultural Sciences, Enshi 445000, China; (A.X.)
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6
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Chen C, Wang G, Li J, Jia Y, Chen Z. Examination of the negative correlation between leaf δ 15N and the N:P ratio across a northeast-southwest transect in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 885:163843. [PMID: 37137362 DOI: 10.1016/j.scitotenv.2023.163843] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 04/23/2023] [Accepted: 04/26/2023] [Indexed: 05/05/2023]
Abstract
Nitrogen (N) and phosphorus (P) are two crucial limiting mineral elements for terrestrial plants. Although the leaf N:P ratio is extensively used to indicate plant nutrient limitations, the critical N:P ratios cannot be universally applied. Some investigations have suggested that leaf nitrogen isotopes (δ15N) can provide another proxy for nutrient limitations along with the N:P ratio, but the negative relationships between N:P and δ15N were mainly limited to fertilization experiments. It will obviously benefit the study of the nature of nutrient limitations if the relationship could be explained more generally. We analyzed leaf δ15N, N, and P contents across a northeast-southwest transect in China. Leaf δ15N was weakly negatively correlated with leaf N:P ratios for all plants, while there was no correlation between them for various plant groups, including different growth forms, genera, and species across the entire N:P range. This suggests that the use of leaf δ15N in indicating the shift of nutrient limitations across the whole N:P range still requires more validated field investigations. Notably, negative relationships between δ15N and N:P hold for plants with N:P ratios between 10 and 20 but not for plants with N:P ratios lower than 10 or higher than 20. That is, changes in leaf δ15N along with the N:P ratio of plants that are co-limited by N and P can exhibit variations in plant nutrient limitations, whereas plants that are strictly limited by N and P cannot. Moreover, these relationships are not altered by vegetation type, soil type, MAP, or MAT, indicating that the use of leaf δ15N in reflecting shifts in nutrient limitations, depending on the plant nutrient limitation range, is general. We examined the relationships between leaf δ15N and the N:P ratio across an extensive transect, providing references for the widespread use of leaf δ15N in reflecting shifts in nutrient limitation.
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Affiliation(s)
- Chongjuan Chen
- School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Guoan Wang
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, Department of Environmental Sciences and Engineering, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Jiazhu Li
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing 100091, China; Institute of Ecological Conservation and Restoration, Chinese Academy of Forestry, Beijing 100091, China.
| | - Yufu Jia
- Center for Soil Protection and Landscape Design, Chinese Academy of Environmental Planning, Beijing 100012, China
| | - Zixun Chen
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, Department of Environmental Sciences and Engineering, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
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7
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Dudney J, Latimer AM, van Mantgem P, Zald H, Willing CE, Nesmith JCB, Cribbs J, Milano E. The energy-water limitation threshold explains divergent drought responses in tree growth, needle length, and stable isotope ratios. GLOBAL CHANGE BIOLOGY 2023; 29:4368-4382. [PMID: 37089078 DOI: 10.1111/gcb.16740] [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: 09/08/2022] [Revised: 02/08/2023] [Accepted: 03/16/2023] [Indexed: 05/03/2023]
Abstract
Predicted increases in extreme droughts will likely cause major shifts in carbon sequestration and forest composition. Although growth declines during drought are widely documented, an increasing number of studies have reported both positive and negative responses to the same drought. These divergent growth patterns may reflect thresholds (i.e., nonlinear responses) promoted by changes in the dominant climatic constraints on tree growth. Here we tested whether stemwood growth exhibited linear or nonlinear responses to temperature and precipitation and whether stemwood growth thresholds co-occurred with multiple thresholds in source and sink processes that limit tree growth. We extracted 772 tree cores, 1398 needle length records, and 1075 stable isotope samples from 27 sites across whitebark pine's (Pinus albicaulis Engelm.) climatic niche in the Sierra Nevada. Our results indicated that a temperature threshold in stemwood growth occurred at 8.4°C (7.12-9.51°C; estimated using fall-spring maximum temperature). This threshold was significantly correlated with thresholds in foliar growth, as well as carbon (δ13 C) and nitrogen (δ15 N) stable isotope ratios, that emerged during drought. These co-occurring thresholds reflected the transition between energy- and water-limited tree growth (i.e., the E-W limitation threshold). This transition likely mediated carbon and nutrient cycling, as well as important differences in growth-defense trade-offs and drought adaptations. Furthermore, whitebark pine growing in energy-limited regions may continue to experience elevated growth in response to climate change. The positive effect of warming, however, may be offset by growth declines in water-limited regions, threatening the long-term sustainability of the recently listed whitebark pine species in the Sierra Nevada.
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Affiliation(s)
- Joan Dudney
- Environmental Studies Program, Santa Barbara, California, USA
- Bren School of Environmental Science & Management, UC Santa Barbara, Santa Barbara, California, USA
| | - Andrew M Latimer
- Department of Plant Sciences, University of California, Davis, California, USA
| | - Phillip van Mantgem
- U.S. Geological Survey, Western Ecological Research Center, Sacramento, California, USA
| | - Harold Zald
- USDA Forest Service, Pacific Northwest Research Station, Corvallis, Oregon, USA
| | - Claire E Willing
- Department of Biology, Stanford University, Stanford, California, USA
- School of Environmental and Forest Sciences, University of Washington, Seattle, Washington, USA
| | | | - Jennifer Cribbs
- Department of Plant Sciences, University of California, Davis, California, USA
| | - Elizabeth Milano
- U.S. Geological Survey, Western Ecological Research Center, Sacramento, California, USA
- USDA Forest Service, Rocky Mountain Research Station, Moscow, Idaho, USA
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8
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Scartazza A, Sbrana C, D'Andrea E, Matteucci G, Rezaie N, Lauteri M. Above- and belowground interplay: Canopy CO 2 uptake, carbon and nitrogen allocation and isotope fractionation along the plant-ectomycorrhiza continuum. PLANT, CELL & ENVIRONMENT 2023; 46:889-900. [PMID: 36541420 DOI: 10.1111/pce.14519] [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: 07/15/2022] [Revised: 12/02/2022] [Accepted: 12/17/2022] [Indexed: 06/17/2023]
Abstract
In forests, mycorrhizal fungi regulate carbon (C) and nitrogen (N) dynamics. We evaluated the interplay among ectomycorrhizas (ECM), ecosystem C fluxes, tree productivity, C and N exchange and isotopic fractionation along the soil-ECM-plant continuum in a Mediterranean beech forest. From bud break to leaf shedding, we monitored: net ecosystem exchange (NEE, a measure of the net exchange of C between an ecosystem and the atmosphere), leaf area index, stem growth, N concentration, δ13 C and δ15 N in rhizosphere soil, ectomycorrhizal fine root tips (ERT), ECM-free fine root portions (NCR) and leaves. Seasonal changes in ERT relative biomass were strictly related to NEE and mimicked those detected in the radial growth. The analysis of δ13 C in ERT, leaves and NCR highlighted the impact of canopy photosynthesis on ERT development and an asynchronous seasonal C allocation strategy between ERT and NCR at the root tips level. Concerning N, δ15 N of leaves was negatively related to that of ERT and dependent on seasonal 15 N differences between ERT and NCR. Our results unravel a synchronous C allocation towards ERT and tree stem driven by the increasing NEE in spring-early summer. Moreover, they highlighted a phenology-dependent 15 N fractionation during N transfer from ECM to their hosts. This evidence, obtained in mature beech trees under natural conditions, may improve the knowledge of Mediterranean forests functionality.
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Affiliation(s)
- Andrea Scartazza
- Research Institute on Terrestrial Ecosystems, National Research Council of Italy (CNR-IRET), Pisa, Italy
- National Biodiversity Future Center (NBFC), Palermo, Italy
| | - Cristiana Sbrana
- Institute of Agricultural Biology and Biotechnology, National Research Council of Italy (CNR-IBBA), Pisa, Italy
| | - Ettore D'Andrea
- National Biodiversity Future Center (NBFC), Palermo, Italy
- Research Institute on Terrestrial Ecosystems, National Research Council of Italy (CNR-IRET), Porano, Italy
| | - Giorgio Matteucci
- National Biodiversity Future Center (NBFC), Palermo, Italy
- Institute for BioEconomy, National Research Council of Italy (CNR-IBE), Sesto Fiorentino, Italy
| | - Negar Rezaie
- Research Institute on Terrestrial Ecosystems, National Research Council of Italy (CNR-IRET), Napoli, Italy
| | - Marco Lauteri
- Research Institute on Terrestrial Ecosystems, National Research Council of Italy (CNR-IRET), Porano, Italy
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9
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Serk H, Nilsson MB, Figueira J, Krüger JP, Leifeld J, Alewell C, Schleucher J. Organochemical Characterization of Peat Reveals Decomposition of Specific Hemicellulose Structures as the Main Cause of Organic Matter Loss in the Acrotelm. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:17410-17419. [PMID: 36399683 PMCID: PMC9730845 DOI: 10.1021/acs.est.2c03513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 10/30/2022] [Accepted: 11/01/2022] [Indexed: 06/16/2023]
Abstract
Peatlands store carbon in the form of dead organic residues. Climate change and human impact impose risks on the sustainability of the peatlands carbon balance due to increased peat decomposition. Here, we investigated molecular changes in the upper peat layers (0-40 cm), inferred from high-resolution vertical depth profiles, from a boreal peatland using two-dimensional 1H-13C nuclear magnetic resonance (NMR) spectroscopy, and comparison to δ13C, δ15N, and carbon and nitrogen content. Effects of hydrological conditions were investigated at respective sites: natural moist, drainage ditch, and natural dry. The molecular characterization revealed preferential degradation of specific side-chain linkages of xylan-type hemicelluloses within 0-14 cm at all sites, indicating organic matter losses up to 25%. In contrast, the xylan backbone, galactomannan-type hemicelluloses, and cellulose were more resistant to degradation and accumulated at the natural moist and drainage site. δ13C, δ15N, and carbon and nitrogen content did not correlate with specific hemicellulose structures but reflected changes in total carbohydrates. Our analysis provides novel insights into peat carbohydrate decomposition and indicates substantial organic matter losses in the acrotelm due to the degradation of specific hemicellulose structures. This suggests that variations in hemicellulose content and structure influence peat stability, which may have important implications with respect to climate change.
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Affiliation(s)
- Henrik Serk
- Department
of Medical Biochemistry and Biophysics, Umeå University, SE-90187 Umeå, Sweden
- Department
of Forest Ecology and Management, Swedish
University of Agricultural Sciences, SE-90183 Umeå, Sweden
| | - Mats B. Nilsson
- Department
of Forest Ecology and Management, Swedish
University of Agricultural Sciences, SE-90183 Umeå, Sweden
| | - João Figueira
- Department
of Chemistry, SciLife Lab, Umeå University, SE-90187 Umeå, Sweden
| | - Jan Paul Krüger
- UDATA
GmbH − Umwelt und Bildung, Hindenburgstrasse 1, 67433 Neustadt an der Weinstraße, Germany
- Departement
Umweltgeowissenschaften, Universität
Basel, Bernoullistrasse
30, CH-4056 Basel, Switzerland
| | - Jens Leifeld
- Departement
Umweltgeowissenschaften, Universität
Basel, Bernoullistrasse
30, CH-4056 Basel, Switzerland
- Agroscope,
Climate and Agriculture Group, Reckenholzstrasse 191, CH-8046 Zurich, Switzerland
| | - Christine Alewell
- Departement
Umweltgeowissenschaften, Universität
Basel, Bernoullistrasse
30, CH-4056 Basel, Switzerland
| | - Jürgen Schleucher
- Department
of Medical Biochemistry and Biophysics, Umeå University, SE-90187 Umeå, Sweden
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10
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Sillo F, Brunetti C, Marroni F, Vita F, Dos Santos Nascimento LB, Vizzini A, Mello A, Balestrini R. Systemic effects of Tuber melanosporum inoculation in two Corylus avellana genotypes. TREE PHYSIOLOGY 2022; 42:1463-1480. [PMID: 35137225 DOI: 10.1093/treephys/tpac012] [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: 09/26/2021] [Accepted: 01/28/2022] [Indexed: 06/14/2023]
Abstract
Roots of the European hazelnut (Corylus avellana L.), i.e., one of the most economically important nut species, form symbiosis with ectomycorrhizal (ECM) fungi, including truffles. Although physical interactions only occur in roots, the presence of mycorrhizal fungi can lead to metabolic changes at a systemic level, i.e., in leaves. However, how root colonization by ECM fungi modifies these processes in the host plant has so far not been widely studied. This work aimed to investigate the response in two C. avellana genotypes, focusing on leaves from plants inoculated with the black truffle Tuber melanosporum Vittad. Transcriptomic profiles of leaves of colonized plants were compared with those of non-colonized plants, as well as sugar and polyphenolic content. Results suggested that T. melanosporum has the potential to support plants in stressed conditions, leading to the systemic regulation of several genes involved in signaling and defense responses. Although further confirmation is needed, our results open new perspectives for future research aimed to highlight novel aspects in ECM symbiosis.
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Affiliation(s)
- Fabiano Sillo
- National Research Council - Institute for Sustainable Plant Protection (CNR-IPSP), Strada della Cacce 73, 10135 Torino, Italy
| | - Cecilia Brunetti
- National Research Council - Institute for Sustainable Plant Protection (CNR-IPSP), Via Madonna del Piano 10, 50019 Firenze, Italy
| | - Fabio Marroni
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Via delle Scienze 206, 33100 Udine, Italy
| | - Federico Vita
- Department of Biology, University of Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy
| | | | - Alfredo Vizzini
- Department of Life Sciences and Systems Biology, University of Torino, Viale P.A. Mattioli 25, 10125 Torino, Italy
- National Research Council - Institute for Sustainable Plant Protection (CNR-IPSP), Viale Mattioli 25, 10125 Torino, Italy
| | - Antonietta Mello
- National Research Council - Institute for Sustainable Plant Protection (CNR-IPSP), Viale Mattioli 25, 10125 Torino, Italy
| | - Raffaella Balestrini
- National Research Council - Institute for Sustainable Plant Protection (CNR-IPSP), Strada della Cacce 73, 10135 Torino, Italy
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11
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Hewitt RE, Alexander HD, Izbicki B, Loranty MM, Natali SM, Walker XJ, Mack MC. Increasing tree density accelerates stand‐level nitrogen cycling at the taiga–tundra ecotone in northeastern Siberia. Ecosphere 2022. [DOI: 10.1002/ecs2.4175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Rebecca E. Hewitt
- Center for Ecosystem Science and Society, Department of Biological Sciences Northern Arizona University Flagstaff Arizona USA
- Department of Environmental Studies Amherst College Amherst Massachusetts USA
| | | | - Brian Izbicki
- Center for Ecosystem Science and Society, Department of Biological Sciences Northern Arizona University Flagstaff Arizona USA
| | | | | | - Xanthe J. Walker
- Center for Ecosystem Science and Society, Department of Biological Sciences Northern Arizona University Flagstaff Arizona USA
| | - Michelle C. Mack
- Center for Ecosystem Science and Society, Department of Biological Sciences Northern Arizona University Flagstaff Arizona USA
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12
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Jespersen RG, Leffler AJ, Väisänen M, Welker JM. Resistance and change in a High Arctic ecosystem, NW Greenland: Differential sensitivity of ecosystem metrics to 15 years of experimental warming and wetting. GLOBAL CHANGE BIOLOGY 2022; 28:1853-1869. [PMID: 34870887 DOI: 10.1111/gcb.16027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 09/23/2021] [Accepted: 11/11/2021] [Indexed: 06/13/2023]
Abstract
Dramatic increases in air temperature and precipitation are occurring in the High Arctic (>70°N), yet few studies have characterized the long-term responses of High Arctic ecosystems to the interactive effects of experimental warming and increased rain. Beginning in 2003, we applied a factorial summer warming and wetting experiment to a polar semidesert in northwest Greenland. In summer 2018, we assessed several metrics of ecosystem structure and function, including plant cover, greenness, ecosystem CO2 exchange, aboveground (leaf, stem) and belowground (litter, root, soil) carbon (C) and nitrogen (N) concentrations (%) and pools, as well as leaf and soil stable isotopes (δ13 C and δ15 N). Wetting induced the most pronounced changes in ecosystem structure, accelerating the expansion of Salix arctica cover by 370% and increasing aboveground C, N, and biomass pools by 94%-101% and root C, N, and biomass pools by 60%-122%, increases which coincided with enhanced net ecosystem CO2 uptake. Further, wetting combined with warming enhanced plot-level greenness, whereas in isolation neither wetting nor warming had an effect. At the plant level, the effects of warming and wetting differed among species and included warming-linked decreases in leaf N and δ15 N in S. arctica, whereas leaf N and δ15 N in Dryas integrifolia did not respond to the climate treatments. Finally, neither plant- nor plot-level C and N allocation patterns nor soil C, N, δ13 C, or δ15 N concentrations changed in response to our manipulations, indicating that these ecosystem metrics may resist climate change, even in the longer term. In sum, our results highlight the importance of summer precipitation in regulating ecosystem structure and function in arid parts of the High Arctic, but they do not completely refute previous findings of resistance in some High Arctic ecosystem properties to climate change.
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Affiliation(s)
- Robert Gus Jespersen
- Department of Biological Sciences, University of Alaska-Anchorage, Anchorage, Alaska, USA
| | - Alan Joshua Leffler
- Department of Natural Resource Management, South Dakota State University, Brookings, South Dakota, USA
| | - Maria Väisänen
- Ecology and Genetics Research Unit, University of Oulu, Oulu, Finland
- Arctic Centre, University of Lapland, Rovaniemi, Finland
| | - Jeffrey M Welker
- UArctic Research Chair, Department of Arctic Ecology & Biogeochemistry, University of Oulu, Oulu, Finland
- University of Alaska-Anchorage, Anchorage, Alaska, USA
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13
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Csilléry K, Buchmann N, Brendel O, Gessler A, Glauser A, Doris Kupferschmid A. Recovery of silver fir (Abies alba Mill.) seedlings from ungulate browsing mirrors soil nitrogen availability. TREE PHYSIOLOGY 2022; 42:273-288. [PMID: 34528673 DOI: 10.1093/treephys/tpab105] [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: 03/21/2021] [Accepted: 08/05/2021] [Indexed: 06/13/2023]
Abstract
Abies alba (Mill.) has a high potential for mitigating climate change in European mountain forests; yet, its natural regeneration is severely limited by ungulate browsing. Here, we simulated browsing in a common garden experiment to study growth and physiological traits, measured from bulk needles, using a randomized block design with two levels of browsing severity and seedlings originating from 19 populations across Switzerland. Genetic factors explained most variation in growth (on average, 51.5%) and physiological traits (10.2%) under control conditions, while heavy browsing considerably reduced the genetic effects on growth (to 30%), but doubled those on physiological traits related to carbon storage. While browsing reduced seedling height, it also lowered seedling water-use efficiency (decreased $\delta ^{13}$C) and increased their $\delta ^{15}$N. Different populations reacted differently to browsing stress, and for seedling height, starch concentration and $\delta ^{15}$N, population differences appeared to be the result of natural selection. First, we found that populations originating from the warmest regions recovered the fastest from browsing stress, and they did so by mobilizing starch from their needles, which suggests a genetic underpinning for a growth-storage trade-off across populations. Second, we found that seedlings originating from mountain populations growing on steep slopes had a higher $\delta ^{15}$N in the common garden than those originating from flat areas, indicating that they have been selected to grow on N-poor, potentially drained, soils. This finding was corroborated by the fact that nitrogen concentration in adult needles was lower on steep slopes than on flat ground, strongly indicating that steep slopes are the most N-poor environments. These results suggest that adaptation to climate and soil nitrogen availability, as well as ungulate browsing pressure, co-determine the regeneration and range limit of silver fir.
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Affiliation(s)
- Katalin Csilléry
- Land Change Science, Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
- Biodiversity and Conservation Biology, Swiss Federal Research Institute WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Nina Buchmann
- Institute of Agricultural Sciences, ETH Zurich, Zurich, Switzerland
| | - Oliver Brendel
- UMR Silva, INRAE, AgroParisTech, Université de Lorraine, Nancy, France
| | - Arthur Gessler
- Forest Dynamics, Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
- Institute of Terrestrial Ecosystems, ETH Zurich, Zurich, Switzerland
| | - Alexandra Glauser
- Forest Resources and Management, Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
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14
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Vesala R, Kiheri H, Hobbie EA, van Dijk N, Dise N, Larmola T. Atmospheric nitrogen enrichment changes nutrient stoichiometry and reduces fungal N supply to peatland ericoid mycorrhizal shrubs. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 794:148737. [PMID: 34323746 DOI: 10.1016/j.scitotenv.2021.148737] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 05/30/2021] [Accepted: 06/25/2021] [Indexed: 06/13/2023]
Abstract
Peatlands store one third of global soil carbon (C) and up to 15% of global soil nitrogen (N) but often have low plant nutrient availability owing to slow organic matter decomposition under acidic and waterlogged conditions. In rainwater-fed ombrotrophic peatlands, elevated atmospheric N deposition has increased N availability with potential consequences to ecosystem nutrient cycling. Here, we studied how 14 years of continuous N addition with either nitrate or ammonium had affected ericoid mycorrhizal (ERM) shrubs at Whim Bog, Scotland. We examined whether enrichment has influenced foliar nutrient stoichiometry and assessed using N stable isotopes whether potential changes in plant nutrient constraints are linked with plant N uptake through ERM fungi versus direct plant uptake. High doses of ammonium alleviated N deficiency in Calluna vulgaris and Erica tetralix, whereas low doses of ammonium and nitrate improved plant phosphorus (P) nutrition, indicated by the lowered foliar N:P ratios. Root acid phosphatase activities correlated positively with foliar N:P ratios, suggesting enhanced P uptake as a result of improved N nutrition. Elevated foliar δ15N of fertilized shrubs suggested that ERM fungi were less important for N supply with N fertilization. Increases in N availability in peat porewater and in direct nonmycorrhizal N uptake likely have reduced plant nitrogen uptake via mycorrhizal pathways. As the mycorrhizal N uptake correlates with the reciprocal C supply from host plants to the soil, such reduction in ERM activity may affect peat microbial communities and even accelerate C loss via decreased ERM activity and enhanced saprotrophic activity. Our results thus introduce a previously unrecognized mechanism for how anthropogenic N pollution may affect nutrient and carbon cycling within peatland ecosystems.
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Affiliation(s)
- Risto Vesala
- Natural Resources Institute Finland (Luke), Finland.
| | - Heikki Kiheri
- Natural Resources Institute Finland (Luke), Finland; Department of Microbiology, Faculty of Agriculture and Forestry, University of Helsinki, Finland
| | - Erik A Hobbie
- Earth Systems Research Center, University of New Hampshire, United States
| | - Netty van Dijk
- UK Centre for Ecology & Hydrology (UKCEH), Edinburgh, UK
| | - Nancy Dise
- UK Centre for Ecology & Hydrology (UKCEH), Edinburgh, UK
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15
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Delevich CA, Koch RA, Aime MC, Henkel TW. Ectomycorrhizal fungal community assembly on seedlings of a Neotropical monodominant tree. Biotropica 2021. [DOI: 10.1111/btp.12989] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Rachel A. Koch
- Department of Botany and Plant Pathology Purdue University West Lafayette IN USA
| | - M. Catherine Aime
- Department of Botany and Plant Pathology Purdue University West Lafayette IN USA
| | - Terry W. Henkel
- Department of Biological Sciences Humboldt State University Arcata CA USA
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16
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Väisänen M, Tuomi M, Bailey H, Welker JM. Plant and soil nitrogen in oligotrophic boreal forest habitats with varying moss depths: does exclusion of large grazers matter? Oecologia 2021; 196:839-849. [PMID: 34080051 PMCID: PMC8292301 DOI: 10.1007/s00442-021-04957-0] [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: 09/26/2020] [Accepted: 05/28/2021] [Indexed: 11/25/2022]
Abstract
The boreal forest consists of drier sunlit and moister-shaded habitats with varying moss abundance. Mosses control vascular plant-soil interactions, yet they all can also be altered by grazers. We determined how 2 decades of reindeer (Rangifer tarandus) exclusion affect feather moss (Pleurozium schreberi) depth, and the accompanying soil N dynamics (total and dissolvable inorganic N, δ15N), plant foliar N, and stable isotopes (δ15N, δ13C) in two contrasting habitats of an oligotrophic Scots pine forest. The study species were pine seedling (Pinus sylvestris L.), bilberry (Vaccinium myrtillus L.), lingonberry (V. vitis-idaea L.), and feather moss. Moss carpet was deeper in shaded than sunlit habitats and increased with grazer exclusion. Humus N content increased in the shade as did humus δ15N, which also increased due to exclusion in the sunlit habitats. Exclusion increased inorganic N concentration in the mineral soil. These soil responses were correlated with moss depth. Foliar chemistry varied due to habitat depending on species identity. Pine seedlings showed higher foliar N content and lower foliar δ15N in the shaded than in the sunlit habitats, while bilberry had both higher foliar N and δ15N in the shade. Thus, foliar δ15N values of co-existing species diverged in the shade indicating enhanced N partitioning. We conclude that despite strong grazing-induced shifts in mosses and subtler shifts in soil N, the N dynamics of vascular vegetation remain unchanged. These indicate that plant-soil interactions are resistant to shifts in grazing intensity, a pattern that appears to be common across boreal oligotrophic forests.
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Affiliation(s)
- Maria Väisänen
- Ecology and Genetics Research Unit, University of Oulu, Oulu, Finland. .,Arctic Centre, University of Lapland, Rovaniemi, Finland.
| | - Maria Tuomi
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway
| | - Hannah Bailey
- Ecology and Genetics Research Unit, University of Oulu, Oulu, Finland
| | - Jeffrey M Welker
- Ecology and Genetics Research Unit, University of Oulu, Oulu, Finland.,Department of Biological Science, University of Alaska Anchorage, Anchorage, AK, USA.,UArctic, Rovaniemi, Finland
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17
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Pellitier PT, Zak DR, Argiroff WA, Upchurch RA. Coupled Shifts in Ectomycorrhizal Communities and Plant Uptake of Organic Nitrogen Along a Soil Gradient: An Isotopic Perspective. Ecosystems 2021. [DOI: 10.1007/s10021-021-00628-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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18
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Pb Stress and Ectomycorrhizas: Strong Protective Proteomic Responses in Poplar Roots Inoculated with Paxillus involutus Isolate and Characterized by Low Root Colonization Intensity. Int J Mol Sci 2021; 22:ijms22094300. [PMID: 33919023 PMCID: PMC8122328 DOI: 10.3390/ijms22094300] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 04/16/2021] [Accepted: 04/18/2021] [Indexed: 01/11/2023] Open
Abstract
The commonly observed increased heavy metal tolerance of ectomycorrhized plants is usually linked with the protective role of the fungal hyphae covering colonized plant root tips. However, the molecular tolerance mechanisms in heavy metal stressed low-colonized ectormyocrrhizal plants characterized by an ectomycorrhiza-triggered increases in growth are unknown. Here, we examined Populus × canescens microcuttings inoculated with the Paxillus involutus isolate, which triggered an increase in poplar growth despite successful colonization of only 1.9% ± 0.8 of root tips. The analyzed plants, lacking a mantle—a protective fungal biofilter—were grown for 6 weeks in agar medium enriched with 0.75 mM Pb(NO3)2. In minimally colonized ‘bare’ roots, the proteome response to Pb was similar to that in noninoculated plants (e.g., higher abundances of PM- and V-type H+ ATPases and lower abundance of ribosomal proteins). However, the more intensive activation of molecular processes leading to Pb sequestration or redirection of the root metabolic flux into amino acid and Pb chelate (phenolics and citrate) biosynthesis coexisted with lower Pb uptake compared to that in controls. The molecular Pb response of inoculated roots was more intense and effective than that of noninoculated roots in poplars.
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19
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Getman‐Pickering ZL, Stack GM, Thaler JS. Fertilizer quantity and type alter mycorrhizae‐conferred growth and resistance to herbivores. J Appl Ecol 2021. [DOI: 10.1111/1365-2664.13833] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
| | - George M. Stack
- Section of Plant Breeding and Genetics Cornell University Ithaca NY USA
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20
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Chen C, Wu Y, Wang S, Liu Z, Wang G. Relationships between leaf δ 15 N and leaf metallic nutrients. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2021; 35:e8970. [PMID: 33047410 DOI: 10.1002/rcm.8970] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 10/05/2020] [Accepted: 10/06/2020] [Indexed: 06/11/2023]
Abstract
RATIONALE Nitrogen (N) isotopic ratios (δ15 N values) of plants are primarily determined by the δ15 N values of their N sources. Metallic nutrients affect plant N uptake. However, there is little knowledge of the relationships between leaf δ15 N values and leaf metallic nutrients. The δ15 N values are often lower in soil nitrate (NO3 - ) than in ammonium (NH4 + ) due to large isotopic fractionation during nitrification. Plants acquire more NO3 - than NH4 + when accumulating high potassium (K), calcium (Ca) and magnesium (Mg) to maintain charge balance. In addition, plants that absorb more NO3 - than NH4 + increase the soil pH and decrease the availability of iron (Fe), manganese (Mn) and zinc (Zn). We therefore hypothesized that leaf δ15 N values correlate negatively with K, Ca and Mg contents, while positively with Fe, Mn and Zn contents. METHODS Leaves of non-N-fixing plants were sampled across an approx. 6000 km transect in China and their δ15 N values and metallic nutrient content were determined using elemental analyzer/isotope ratio mass spectrometry. RESULTS Inconsistent with the hypothesis, leaf δ15 N values correlated positively with leaf K, Ca and Mg, indicating higher δ15 N values of soil NO3 - than NH4 + . Higher δ15 N values of soil NO3 - revealed stronger denitrification than nitrification in the study regions because isotopic fractionation occurs during both processes. Leaf δ15 N values correlated negatively with Fe, relating to decreases in soil Fe availability, which might be attributed to oxidation of Fe2+ to Fe3+ supplying electrons for denitrification, while greater uptake of NO3 - than NH4 + of plants increases soil pH. Leaf δ15 N values correlated positively with Zn and did not correlate with Mn. These observed relationships between leaf δ15 N values and metallic nutrients, except Mn, were independent of vegetation or soil types. CONCLUSIONS This study has enriched our knowledge of associations between metallic nutrients and N cycling in plant-soil systems, especially for the roles of Fe in soil N transformations and K, Ca and Mg in plant N uptake.
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Affiliation(s)
- Chongjuan Chen
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, Department of Environmental Sciences and Engineering, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Yingjie Wu
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, Department of Environmental Sciences and Engineering, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Shuhan Wang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Zhaotong Liu
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, Department of Environmental Sciences and Engineering, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Guoan Wang
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, Department of Environmental Sciences and Engineering, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
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21
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Tatsumi C, Hyodo F, Taniguchi T, Shi W, Koba K, Fukushima K, Du S, Yamanaka N, Templer P, Tateno R. Arbuscular Mycorrhizal Community in Roots and Nitrogen Uptake Patterns of Understory Trees Beneath Ectomycorrhizal and Non-ectomycorrhizal Overstory Trees. FRONTIERS IN PLANT SCIENCE 2021; 11:583585. [PMID: 33519844 PMCID: PMC7840530 DOI: 10.3389/fpls.2020.583585] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 12/07/2020] [Indexed: 06/12/2023]
Abstract
Nitrogen (N) is an essential plant nutrient, and plants can take up N from several sources, including via mycorrhizal fungal associations. The N uptake patterns of understory plants may vary beneath different types of overstory trees, especially through the difference in their type of mycorrhizal association (arbuscular mycorrhizal, AM; or ectomycorrhizal, ECM), because soil mycorrhizal community and N availability differ beneath AM (non-ECM) and ECM overstory trees (e.g., relatively low nitrate content beneath ECM overstory trees). To test this hypothesis, we examined six co-existing AM-symbiotic understory tree species common beneath both AM-symbiotic black locust (non-ECM) and ECM-symbiotic oak trees of dryland forests in China. We measured AM fungal community composition of roots and natural abundance stable isotopic composition of N (δ15N) in plant leaves, roots, and soils. The root mycorrhizal community composition of understory trees did not significantly differ between beneath non-ECM and ECM overstory trees, although some OTUs more frequently appeared beneath non-ECM trees. Understory trees beneath non-ECM overstory trees had similar δ15N values in leaves and soil nitrate, suggesting that they took up most of their nitrogen as nitrate. Beneath ECM overstory trees, understory trees had consistently lower leaf than root δ15N, suggesting they depended on mycorrhizal fungi for N acquisition since mycorrhizal fungi transfer isotopically light N to host plants. Additionally, leaf N concentrations in the understory trees were lower beneath ECM than the non-ECM overstory trees. Our results show that, without large differences in root mycorrhizal community, the N uptake patterns of understory trees vary between beneath different overstory trees.
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Affiliation(s)
- Chikae Tatsumi
- Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
- Graduate School of Agriculture, Kyoto University, Kyoto, Japan
- Department of Biology, Boston University, Boston, MA, United States
| | - Fujio Hyodo
- Research Core for Interdisciplinary Sciences, Okayama University, Okayama, Japan
| | | | - Weiyu Shi
- School of Geographical Sciences, Southwest University, Chongqing, China
| | - Keisuke Koba
- Center for Ecological Research, Kyoto University, Shiga, Japan
| | | | - Sheng Du
- State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences, Beijing, China
| | | | - Pamela Templer
- Department of Biology, Boston University, Boston, MA, United States
| | - Ryunosuke Tateno
- Field Science Education and Research Center, Kyoto University, Kyoto, Japan
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22
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Szuba A, Marczak Ł, Ratajczak I. Metabolome adjustments in ectomycorrhizal Populus × canescens associated with strong promotion of plant growth by Paxillus involutus despite a very low root colonization rate. TREE PHYSIOLOGY 2020; 40:1726-1743. [PMID: 32761190 DOI: 10.1093/treephys/tpaa100] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 07/13/2020] [Accepted: 08/02/2020] [Indexed: 06/11/2023]
Abstract
It is believed that resource exchange, which is responsible for intensified growth of ectomycorrhizal plants, occurs in the fungus-plant interface. However, increasing evidence indicates that such intensified plant growth, especially root growth promotion, may be independent of root colonization. Nevertheless, the molecular adjustments in low-colonized plants remain poorly understood. Here, we analysed the metabolome of Populus × canescens microcuttings characterized by significantly increased growth triggered by inoculation with Paxillus involutus, which successfully colonized only 2.1 ± 0.3% of root tips. High-throughput metabolomic analyses of leaves, stems and roots of Populus × canescens microcuttings supplemented with leaf proteome data were performed to determine ectomycorrhiza-triggered changes in N-, P- and C-compounds. The molecular adjustments were relatively low in low-colonized (M) plants. Nevertheless, the levels of foliar phenolic compounds were significantly increased in M plants. Increases of total soluble carbohydrates, starch as well as P concentrations were also observed in M leaves along with the increased abundance of the majority of glycerophosphocholines detected in M roots. However, compared with the leaves of the non-inoculated controls, M leaves presented lower concentrations of both N and most photosynthesis-related proteins and all individual mono- and disaccharides. In M stems, only a few compounds with different abundances were detected, including a decrease in carbohydrates, which was also detected in M roots. Thus, these results suggest that the growth improvement of low-colonized poplar trees is independent of an increased photosynthesis rate, massively increased resource (C:N) exchange and delivery of most nutrients to leaves. The mechanism responsible for poplar growth promotion remains unknown but may be related to increased P uptake, subtle leaf pigment changes, the abundance of certain photosynthetic proteins, slight increases in stem and root amino acid levels and the increase in flavonoids (increasing the antioxidant capacity in poplar), all of which improve the fitness of low-colonized poplars.
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Affiliation(s)
- Agnieszka Szuba
- Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, PL-62035 Kórnik, Poland
| | - Łukasz Marczak
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Z. Noskowskiego 12/14 PL-61704 Poznań, Poland
| | - Izabela Ratajczak
- Department of Chemistry, Poznań University of Life Sciences, Wojska Polskiego 75, PL-60625 Poznan, Poland
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23
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Acuña-Rodríguez IS, Galán A, Torres-Díaz C, Atala C, Molina-Montenegro MA. Fungal Symbionts Enhance N-Uptake for Antarctic Plants Even in Non-N Limited Soils. Front Microbiol 2020; 11:575563. [PMID: 33193189 PMCID: PMC7645117 DOI: 10.3389/fmicb.2020.575563] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 10/05/2020] [Indexed: 11/25/2022] Open
Abstract
Plant-fungi interactions have been identified as fundamental drivers of the plant host performance, particularly in cold environments where organic matter degradation rates are slow, precisely for the capacity of the fungal symbiont to enhance the availability of labile nitrogen (N) in the plant rhizosphere. Nevertheless, these positive effects appear to be modulated by the composition and amount of the N pool in the soil, being greater when plant hosts are growing where N is scarce as is the case of Antarctic soils. Nevertheless, in some coastal areas of this continent, seabirds and marine mammal colonies exert, through their accumulated feces and urine a strong influence on the edaphic N content surrounding their aggregation points. To evaluate if the fungal symbionts (root endophytes), associated to the only two Antarctic vascular plants Colobanthus quitensis and Deschampsia antarctica, act as N-uptake enhancers, even in such N-rich conditions as those found around animal influence, we assessed, under controlled conditions, the process of N mineralization in soil by the accumulation of NH4 + in the rizhosphere and the biomass accumulation of plants with (E+) and without (E-) fungal symbionts. Complementarily, taking advantage of the isotopic N-fractionation that root-fungal symbionts exert on organic N molecules during its acquisition process, we also determined if endophytes actively participate in the Antarctic plants N-uptake, when inorganic N is not a limiting factor, by estimating the δ15N isotopic signatures in leaves. Overall, symbiotic interaction increased the availability of NH4 + in the rhizosphere of both species. As expected, the enhanced availability of inorganic N resulted in a higher final biomass in E + compared with E- plants of both species. In addition, we found that the positive role of fungal symbionts was also actively linked to the process of N-uptake in both species, evidenced by the contrasting δ15N signatures present in E+ (-0.4 to -2.3‰) relative to E- plants (2.7-3.1‰). In conclusion, despite being grown under rich N soils, the two Antarctic vascular plants showed that the presence of root-fungal endophytes, furthermore enhanced the availability of inorganic N sources in the rhizosphere, has a positive impact in their biomass, remarking the active participation of these endophytes in the N-uptake process for plants inhabiting the Antarctic continent.
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Affiliation(s)
- Ian S. Acuña-Rodríguez
- Laboratorio de Biología Vegetal, Instituto de Ciencias Biológicas, Universidad de Talca, Talca, Chile
| | - Alexander Galán
- Centro de Investigación en Estudios Avanzados del Maule (CIEAM), Vicerrectoría de Investigación y Postgrado, Universidad Católica del Maule, Talca, Chile
- Departamento de Obras Civiles, Facultad de Ciencias de la Ingeniería, Universidad Católica del Maule, Talca, Chile
- Centro Regional de Estudios Ambientales (CREA), Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - Cristian Torres-Díaz
- Laboratorio de Genómica y Biodiversidad (LGB), Departamento de Ciencias Naturales, Universidad del Bío-Bío, Chillán, Chile
| | - Cristian Atala
- Laboratorio de Anatomía y Ecología Funcional de Plantas (AEF), Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Campus Curauma, Valparaíso, Chile
| | - Marco A. Molina-Montenegro
- Laboratorio de Biología Vegetal, Instituto de Ciencias Biológicas, Universidad de Talca, Talca, Chile
- Centro de Investigación en Estudios Avanzados del Maule (CIEAM), Vicerrectoría de Investigación y Postgrado, Universidad Católica del Maule, Talca, Chile
- Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Facultad de Ciencias del Mar, Universidad Católica del Norte, Coquimbo, Chile
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Weemstra M, Peay KG, Davies SJ, Mohamad M, Itoh A, Tan S, Russo SE. Lithological constraints on resource economies shape the mycorrhizal composition of a Bornean rain forest. THE NEW PHYTOLOGIST 2020; 228:253-268. [PMID: 32436227 DOI: 10.1111/nph.16672] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 05/11/2020] [Indexed: 06/11/2023]
Abstract
Arbuscular mycorrhizal fungi (AMF) and ectomycorrhizal fungi (EMF) produce contrasting plant-soil feedbacks, but how these feedbacks are constrained by lithology is poorly understood. We investigated the hypothesis that lithological drivers of soil fertility filter plant resource economic strategies in ways that influence the relative fitness of trees with AMF or EMF symbioses in a Bornean rain forest containing species with both mycorrhizal strategies. Using forest inventory data on 1245 tree species, we found that although AMF-hosting trees had greater relative dominance on all soil types, with declining lithological soil fertility EMF-hosting trees became more dominant. Data on 13 leaf traits and wood density for a total of 150 species showed that variation was almost always associated with soil type, whereas for six leaf traits (structural properties; carbon, nitrogen, phosphorus ratios, nitrogen isotopes), variation was also associated with mycorrhizal strategy. EMF-hosting species had slower leaf economics than AMF-hosts, demonstrating the central role of mycorrhizal symbiosis in plant resource economies. At the global scale, climate has been shown to shape forest mycorrhizal composition, but here we show that in communities it depends on soil lithology, suggesting scale-dependent abiotic factors influence feedbacks underlying the relative fitness of different mycorrhizal strategies.
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Affiliation(s)
- Monique Weemstra
- Centre d'Ecologie Fonctionnelle et Evolutive, UMR 5175 (CNRS - Université de Montpellier - Université Paul-Valéry, Montpellier), 1919 route de Mende, Montpellier, 34293, France
- School of Biological Sciences, University of Nebraska - Lincoln, Lincoln, NE, 68588-0118, USA
| | - Kabir G Peay
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
| | - Stuart J Davies
- Forest Global Earth Observatory, Smithsonian Tropical Research Institute, PO Box 37012, Washington, DC, 20013, USA
| | - Mohizah Mohamad
- Forest Department Sarawak, Wisma Sumber Alam, Petra Jaya, Kuching, Sarawak, 93660, Malaysia
| | - Akira Itoh
- Graduate School of Science, Osaka City University, Osaka, 558-8585, Japan
| | - Sylvester Tan
- Smithsonian ForestGEO, Lambir Hills National Park, Km32 Miri-Bintulu Road, Miri, Sarawak, 9800, Malaysia
| | - Sabrina E Russo
- School of Biological Sciences, University of Nebraska - Lincoln, Lincoln, NE, 68588-0118, USA
- Center for Plant Science Innovation, University of Nebraska - Lincoln, Lincoln, NE, 68588-0660, USA
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Sun K, Zhang W, Yuan J, Song SL, Wu H, Tang MJ, Xu FJ, Xie XG, Dai CC. Nitrogen fertilizer-regulated plant-fungi interaction is related to root invertase-induced hexose generation. FEMS Microbiol Ecol 2020; 96:5869223. [PMID: 32643762 DOI: 10.1093/femsec/fiaa139] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 07/08/2020] [Indexed: 11/13/2022] Open
Abstract
The mechanisms underlying nitrogen (N)-regulated plant-fungi interactions are not well understood. N application modulates plant carbohydrate (C) sinks and is involved in the overall plant-fungal association. We hypothesized that N regulates plant-fungi interactions by influencing the carbohydrate metabolism. The mutualistic fungus Phomopsis liquidambaris was found to prioritize host hexose resources through in vitro culture assays and in planta inoculation. Rice-Ph. liquidambaris systems were exposed to N gradients ranging from N-deficient to N-abundant conditions to study whether and how the sugar composition was involved in the dynamics of N-mediated fungal colonization. We found that root soluble acid invertases were activated, resulting in increased hexose fluxes in inoculated roots. These fluxes positively influenced fungal colonization, especially under N-deficient conditions. Further experiments manipulating the carbohydrate composition and root invertase activity through sugar feeding, chemical treatments and the use of different soil types revealed that the external disturbance of root invertase could reduce endophytic colonization and eliminate endophyte-induced host benefits under N-deficient conditions. Collectively, these results suggest that the activation of root invertase is related to N deficiency-enhanced endophytic colonization via increased hexose generation. Certain combinations of farmland ecosystems with suitable N inputs could be implemented to maximize the benefits of plant-fungi associations.
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Affiliation(s)
- Kai Sun
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Jiangsu Province, China
| | - Wei Zhang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Jiangsu Province, China
| | - Jie Yuan
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Jiangsu Province, China
| | - Shi-Li Song
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Jiangsu Province, China
| | - Hao Wu
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Jiangsu Province, China
| | - Meng-Jun Tang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Jiangsu Province, China
| | - Fang-Ji Xu
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Jiangsu Province, China
| | - Xing-Guang Xie
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Jiangsu Province, China
| | - Chuan-Chao Dai
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Jiangsu Province, China
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Hewitt RE, Chapin FS, Hollingsworth TN, Mack MC, Rocha AV, Taylor DL. Limited overall impacts of ectomycorrhizal inoculation on recruitment of boreal trees into Arctic tundra following wildfire belie species-specific responses. PLoS One 2020; 15:e0235932. [PMID: 32645087 PMCID: PMC7347221 DOI: 10.1371/journal.pone.0235932] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 06/24/2020] [Indexed: 01/16/2023] Open
Abstract
We tested whether post-fire seedling establishment of common boreal tree and expanding shrub species at treeline and in Arctic tundra is facilitated by co-migration of boreal forest mycorrhizal fungi. Wildfires are anticipated to facilitate biome shifts at the forest-tundra ecotone by improving seedbed conditions for recruiting boreal species; at the same time fire alters the composition and availability of mycorrhizal fungi critical to seedling performance. To determine the role of root-associated fungi (RAF) in post-fire seedling recruitment and future biome shifts, we outplanted four dominant boreal tree and shrub species inoculated with one of three treatments at treeline and in tundra: burned boreal forest, unburned boreal forest, or a control treatment of sterilized inoculum. We compared survivorship, growth, and physiological performance of the seedlings in relation to mycorrhizal inoculum treatment and among host species, characterized the RAF communities based on ITS-rDNA sequencing of individual root tips sampled from surviving seedlings, and tested for correlations between RAF composition and the inoculation treatments, host species, and duration of the experiment. We explored correlations between RAF composition and seedling metrics. Both live and sterile autoclaved inoculation treatments had similar effects on seedling survivorship and growth for all species. RAF composition did not vary by treatment, suggesting that most colonization was due to local fungi. However, seedling traits and growth were correlated with RAF species composition, colonization, and the relative abundance of specific RAF taxa. Picea sp. performance in particular showed strong co-variation with RAF metrics. Our results suggest that mycorrhizal co-migration is not a primary limiting factor to boreal seedling recruitment because the experimental provision of inoculum did not affect seedling recruitment; yet, RAF did influence seedling performance, particularly resident RAF at treeline and in tundra, suggesting that mycorrhizal fungi are important to vegetation processes at the treeline-tundra ecotone.
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Affiliation(s)
- Rebecca E. Hewitt
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, United States of America
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, United States of America
| | - F. Stuart Chapin
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, United States of America
| | - Teresa N. Hollingsworth
- US Forest Service, Pacific Northwest Research Station, Boreal Ecology Cooperative Research Unit, Fairbanks, Alaska, United States of America
| | - Michelle C. Mack
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, United States of America
| | - Adrian V. Rocha
- Department of Biological Sciences and the Environmental Change Initiative, University of Notre Dame, Notre Dame, Indiana, United States of America
| | - D. Lee Taylor
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, United States of America
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, United States of America
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Szuba A, Marczak Ł, Ratajczak I, Kasprowicz-Maluśki A, Mucha J. Integrated proteomic and metabolomic analyses revealed molecular adjustments in Populus × canescens colonized with the ectomycorrhizal fungus Paxillus involutus, which limited plant host growth. Environ Microbiol 2020; 22:3754-3771. [PMID: 32608104 DOI: 10.1111/1462-2920.15146] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 06/24/2020] [Accepted: 06/28/2020] [Indexed: 11/27/2022]
Abstract
Ectomycorrhizae (ECMs) are a highly context-dependent interactions that are not always beneficial for the plant host, sometimes leading to a decrease in plant growth. However, the molecular status of these plants remains unknown. We studied Populus × canescens microcuttings characterized by impaired growth in response to colonization by a Paxillus involutus strain via integrative proteomics-metabolomics analyses. The analysed strain was characterized by low compatibility and formed only mantles, not a Hartig net, in the majority of root tips. The increased abundance of photosynthetic proteins and foliar carbohydrates co-occurred with signals of intensified resource exchange via the stems of colonized plants. In the roots, intensified C metabolism resulted in the biosynthesis of secondary C compounds unavailable to the fungal partner but also C skeletons necessary to increase insufficient N uptake from the hyphae. The stress response was also detected in colonized plants but was similar to that reported previously during mutualistic ECM interactions. In colonized poplar plants, mechanisms to prevent imbalanced C/N trade-offs were activated. Root metabolism strongly depended on features of the whole plant, especially the foliar C/N budget. However, despite ECM-triggered growth impairment and the foliar nutrient status, the fungal partner was recognized to be a symbiotic partner.
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Affiliation(s)
- Agnieszka Szuba
- Polish Academy of Sciences, Institute of Dendrology, Parkowa 5, Kórnik, PL-62035, Poland
| | - Łukasz Marczak
- Polish Academy of Sciences, Institute of Bioorganic Chemistry, Noskowskiego 12/14, Poznań, PL-61704, Poland
| | - Izabela Ratajczak
- Department of Chemistry, Poznań University of Life Sciences, Wojska Polskiego 75, Poznań, PL-60625, Poland
| | | | - Joanna Mucha
- Polish Academy of Sciences, Institute of Dendrology, Parkowa 5, Kórnik, PL-62035, Poland
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Smith JM, Whiteside MD, Jones MD. Rapid nitrogen loss from ectomycorrhizal pine germinants signaled by their fungal symbiont. MYCORRHIZA 2020; 30:407-417. [PMID: 32363468 PMCID: PMC7314718 DOI: 10.1007/s00572-020-00959-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 04/17/2020] [Indexed: 06/11/2023]
Abstract
Ectomycorrhizal fungi supply their plant partners with nitrogen but can also retain substantial amounts. The concentration of nitrogen in the soil and the amount of carbon supplied from the host seem to influence the proportion of N retained by the fungus. In an experiment designed to determine whether differential supply of nitrogen to two plants influenced nitrogen transfer from fungus to plant within a mycorrhizal network, we observed rapid, substantial loss of nitrogen from pine seedlings. The loss occurred when the mycorrhizal fungus experienced a sudden increase in nitrogen supply. We grew Pinus contorta seedlings in association with Suillus tomentosus in low-nitrogen microcosms where some nitrogen was accessible only by hyphae. After 70 days, foliage of some seedlings was treated with nitrogen. Three days later, hyphal nutrient media were replaced with water or a solution containing nitrogen. Foliar treatment did not affect nitrogen transfer by the fungus to shoots, but by day 75, seedling nitrogen contents had dropped by 60% in microcosms where nitrogen had been added to the hyphal compartments. Those seedlings retained only 55% of the nitrogen originally present in the seed. Loss of nitrogen did not occur if water was added or the hyphae were severed. Because of the severing effect, we concluded that S. tomentosus triggered the loss of seedling nitrogen. Nitrogen may have been lost through increased root exudation or transfer to the fungus. Access to nitrogen from nutrient-rich germinants would benefit rhizosphere microorganisms, including ectomycorrhizal fungi colonizing pine from spores after wildfire.
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Affiliation(s)
- Joshua M Smith
- Biology Department and Okanagan Institute of Biodiversity Resilience and Ecosystem Services, University of British Columbia, Okanagan campus, Kelowna, British Columbia, V1V 1V7, Canada
- Xeriscape Endemic Nursery & Ecological Solutions, West Kelowna, British Columbia, V1Z 1Z9, Canada
| | - Matthew D Whiteside
- Biology Department and Okanagan Institute of Biodiversity Resilience and Ecosystem Services, University of British Columbia, Okanagan campus, Kelowna, British Columbia, V1V 1V7, Canada
| | - Melanie D Jones
- Biology Department and Okanagan Institute of Biodiversity Resilience and Ecosystem Services, University of British Columbia, Okanagan campus, Kelowna, British Columbia, V1V 1V7, Canada.
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29
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Jach-Smith LC, Jackson RD. Inorganic N addition replaces N supplied to switchgrass (Panicum virgatum) by arbuscular mycorrhizal fungi. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2020; 30:e02047. [PMID: 31758822 DOI: 10.1002/eap.2047] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 02/20/2019] [Accepted: 04/25/2019] [Indexed: 06/10/2023]
Abstract
Arbuscular mycorrhizal fungi (AMF) provide many benefits in agroecosystems including improved soil tilth, carbon sequestration, and water and nutrient transfer to plants. AMF are known to affect plant nitrogen (N) dynamics and transfer N to plants, but there have been few studies addressing whether the amount of N transferred to plants by AMF is agronomically relevant. We used δ15 N natural abundance methods and δ15 N mass balance equations to estimate the amount of plant N derived from AMF transfer in perennial grasses managed for bioenergy production under different N addition treatments (0, 56, and 196 kg N/ha). Differentiation of δ15 N among plant, soil N, and AMF pools was higher than anticipated leading to calculations of 34-55% of plant N transferred by AMF in the treatments receiving no N addition to 6-22% of plant N transferred to plants in high-N addition treatments. AMF extra-radical hyphae biomass was significantly reduced in the high-N (196 kg N/ha) addition treatments, which was negatively correlated to enriched plant δ15 N. Our results suggest that N addition decreases AMF N transfer to plants. When N was limiting to plant growth, AMF supplied agronomically significant amounts of plant N, and a higher proportion of overall plant N. Because differentiation between N pools was greater than expected, stable isotope measurements can be used to estimate N transfer to AMF plant hosts.
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Affiliation(s)
- Laura C Jach-Smith
- Nelson Institute for Environmental Studies, University of Wisconsin-Madison, 550 North Park Street, Madison, Wisconsin, 53706, USA
- DOE-Great Lakes Bioenergy Research Center, 1552 University Avenue, Madison, Wisconsin, 53726, USA
| | - Randall D Jackson
- Nelson Institute for Environmental Studies, University of Wisconsin-Madison, 550 North Park Street, Madison, Wisconsin, 53706, USA
- DOE-Great Lakes Bioenergy Research Center, 1552 University Avenue, Madison, Wisconsin, 53726, USA
- Department of Agronomy, University of Wisconsin-Madison, 1575 Linden Drive, Madison, Wisconsin, 53706, USA
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Stuart EK, Plett KL. Digging Deeper: In Search of the Mechanisms of Carbon and Nitrogen Exchange in Ectomycorrhizal Symbioses. FRONTIERS IN PLANT SCIENCE 2020; 10:1658. [PMID: 31993064 PMCID: PMC6971170 DOI: 10.3389/fpls.2019.01658] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 11/25/2019] [Indexed: 05/12/2023]
Abstract
Symbiosis with ectomycorrhizal (ECM) fungi is an advantageous partnership for trees in nutrient-limited environments. Ectomycorrhizal fungi colonize the roots of their hosts and improve their access to nutrients, usually nitrogen (N) and, in exchange, trees deliver a significant portion of their photosynthetic carbon (C) to the fungi. This nutrient exchange affects key soil processes and nutrient cycling, as well as plant health, and is therefore central to forest ecosystem functioning. Due to their ecological importance, there is a need to more accurately understand ECM fungal mediated C and N movement within forest ecosystems such that we can better model and predict their role in soil processes both now and under future climate scenarios. There are a number of hurdles that we must overcome, however, before this is achievable such as understanding how the evolutionary history of ECM fungi and their inter- and intra- species variability affect their function. Further, there is currently no generally accepted universal mechanism that appears to govern the flux of nutrients between fungal and plant partners. Here, we consider the current state of knowledge on N acquisition and transport by ECM fungi and how C and N exchange may be related or affected by environmental conditions such as N availability. We emphasize the role that modern genomic analysis, molecular biology techniques and more comprehensive and standardized experimental designs may have in bringing cohesion to the numerous ecological studies in this area and assist us in better understanding this important symbiosis. These approaches will help to build unified models of nutrient exchange and develop diagnostic tools to study these fungi at various scales and environments.
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Affiliation(s)
| | - Krista L. Plett
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, Australia
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Szuba A, Marczak Ł, Karliński L, Mucha J, Tomaszewski D. Regulation of the leaf proteome by inoculation of Populus × canescens with two Paxillus involutus isolates differing in root colonization rates. MYCORRHIZA 2019; 29:503-517. [PMID: 31456074 DOI: 10.1007/s00572-019-00910-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 08/09/2019] [Indexed: 06/10/2023]
Abstract
During ectomycorrhizal symbioses, up to 30% of the carbon produced in leaves may be translocated to the fungal partner. Given that the leaf response to root colonization is largely unknown, we performed a leaf proteome analysis of Populus × canescens inoculated in vitro with two isolates of Paxillus involutus significantly differing in root colonization rates (65 ± 7% vs 14 ± 7%), together with plant growth and leaf biochemistry analyses to determine the response of plant leaves to ectomycorrhizal root colonization. The isolate that more efficiently colonized roots (isolate H) affected 9.1% of the leaf proteome compared with control plants. Simultaneously, ectomycorrhiza in isolate H-inoculated plants led to improved plant growth and an increased abundance of leaf proteins involved in protein turnover, stress response, carbohydrate metabolism, and photosynthesis. The protein increment was also correlated with increases in chlorophyll, foliar carbon, and carbohydrate contents. Although inoculation of P. × canescens roots with the other P. involutus isolate (isolate L, characterized by a low root colonization ratio) affected 6.8% of the leaf proteome compared with control plants, most proteins were downregulated. The proteomic signals of increased carbohydrate biosynthesis were not detected, and carbohydrate, carbon, and leaf pigment levels and plant biomass did not differ from the noninoculated plants. Our results revealed that the upregulation of the photosynthetic protein abundance and levels of leaf carbohydrate are positively related to rates of root colonization. Upregulation of photosynthetic proteins, chlorophyll, and leaf carbohydrate levels in ectomycorrhizal plants was positively related to root colonization rates and resulted in increased carbon translocation and sequestration underground.
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Affiliation(s)
- Agnieszka Szuba
- Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035, Kórnik, Poland.
| | - Łukasz Marczak
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Z. Noskowskiego 12/14, 61-704, Poznań, Poland
| | - Leszek Karliński
- Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035, Kórnik, Poland
| | - Joanna Mucha
- Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035, Kórnik, Poland
| | - Dominik Tomaszewski
- Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035, Kórnik, Poland
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Accounting for Carbon Flux to Mycorrhizal Fungi May Resolve Discrepancies in Forest Carbon Budgets. Ecosystems 2019. [DOI: 10.1007/s10021-019-00440-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Buzzard V, Michaletz ST, Deng Y, He Z, Ning D, Shen L, Tu Q, Van Nostrand JD, Voordeckers JW, Wang J, Weiser MD, Kaspari M, Waide RB, Zhou J, Enquist BJ. Continental scale structuring of forest and soil diversity via functional traits. Nat Ecol Evol 2019; 3:1298-1308. [DOI: 10.1038/s41559-019-0954-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Accepted: 06/25/2019] [Indexed: 11/09/2022]
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Leaf and Soil δ15N Patterns Along Elevational Gradients at Both Treelines and Shrublines in Three Different Climate Zones. FORESTS 2019. [DOI: 10.3390/f10070557] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The natural abundance of stable nitrogen (N) isotope (δ15N) in plants and soils can reflect N cycling processes in ecosystems. However, we still do not fully understand patterns of plant and soil δ15N at alpine treelines and shrublines in different climate zones. We measured δ15N and N concentration in leaves of trees and shrubs and also in soils along elevational gradients from lower altitudes to the upper limits of treelines and shrublines in subtropical, dry- and wet-temperate regions in China. The patterns of leaf δ15N in trees and shrubs in response to altitude changes were consistent, with lower values occurring at higher altitude in all three climate zones, but such patterns did not exist for leaf Δδ15N and soil δ15N. Average δ15N values of leaves (−1.2‰) and soils (5.6‰) in the subtropical region were significantly higher than those in the two temperate regions (−3.4‰ and 3.2‰, respectively). Significant higher δ15N values in subtro4pical forest compared with temperate forests prove that N cycles are more open in warm regions. The different responses of leaf and soil δ15N to altitude indicate complex mechanisms of soil biogeochemical process and N sources uptake with environmental variations.
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Fertilization alters nitrogen isotopes and concentrations in ectomycorrhizal fungi and soil in pine forests. FUNGAL ECOL 2019. [DOI: 10.1016/j.funeco.2018.12.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Vaario LM, Sah SP, Norisada M, Narimatsu M, Matsushita N. Tricholoma matsutake may take more nitrogen in the organic form than other ectomycorrhizal fungi for its sporocarp development: the isotopic evidence. MYCORRHIZA 2019; 29:51-59. [PMID: 30406843 PMCID: PMC6311186 DOI: 10.1007/s00572-018-0870-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 10/16/2018] [Indexed: 05/26/2023]
Abstract
Tricholoma matsutake is an ectomycorrhizal (ECM) fungus capable of in vitro saprotrophic growth, but the sources of C and N used to generate sporocarps in vivo are not well understood. We examined natural abundance isotope data to investigate this phenomenon. For this purpose, C, N and their stable isotopes (13C, 15N) content of fungal sporocarps and their potential nutrient sources (i.e., foliage, litter, fine roots, wood, and soil) were investigated from two well-studied sites in Finland and Japan. Our results show that δ13C values of T. matsutake and other fungal groups are consistent with those of most studies, but a very high δ15N value (16.8‰ ± 2.3) is observed in T. matsutake. Such isotopic pattern of fungal δ15N suggests that matsutake has a greater proteolytic potential to digest chemically complex 15N-enriched organic matter and hydrophobic hyphae. This assumption is further supported by a significant and positive correlation between δ13Ccap-stipe and δ15Ncap-stipe exclusively in T. matsutake, which suggests common C and N sources (protein) possible for isotopically enriched cap. The 13C increase of caps relative to stipe presumably reflects greater contents of 13C-enriched protein than 13C-depleted chitin. We conclude that T. matsutake is a typical ECM fungus which obtains for its sporocarp development for both C and N from a common protein source (vs. photosynthetic carbon) present in soil organic matter.
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Affiliation(s)
- Lu-Min Vaario
- Department of Forest Sciences, University of Helsinki, PO Box 27, FI-00014, Helsinki, Finland.
- Asian Natural Environmental Science Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, Japan.
| | - Shambhu Prasad Sah
- Department of Forest Sciences, University of Helsinki, PO Box 27, FI-00014, Helsinki, Finland
| | - Mariko Norisada
- Asian Natural Environmental Science Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, Japan
| | - Maki Narimatsu
- Iwate Prefectural Forestry Technology Center, 560-11 Kemuyama, Yahaba, Iwate, Japan
| | - Norihisa Matsushita
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, Japan
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Hayashi M, Lopez Caceres ML, Nobori Y, Mijidsuren B, Boy J. Nitrogen isotope pattern in Mongolian larch stands at the southern Eurasian boreal forest boundary. ISOTOPES IN ENVIRONMENTAL AND HEALTH STUDIES 2018; 54:608-621. [PMID: 30156882 DOI: 10.1080/10256016.2018.1509073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 06/13/2018] [Indexed: 06/08/2023]
Abstract
In the last decades a drastic increase in air temperature but a stable precipitation regime in Mongolia has led to gradual drying conditions. Thus, we evaluated the effect of spatial and climatic characteristics on the soil-plant nitrogen dynamics in three representative larch stands (Larix sibirica) with different geographical and climatic conditions using stable nitrogen isotopes. The results showed significant differences in the soil inorganic N content among sites and consequently a different isotopic composition in the plant-soil system. Litter, bark and wood had the lowest δ15N values for all sites, slightly higher δ15N values for needles, while the highest δ15N values were observed for roots and soil. These differences could be the result of the larch stands age themselves, but were in agreement with the spatial and climatic characteristics of the sites. Based on the δ15N value a higher reliance on ectomycorrhizal fungi (ECMF) was observed in the warmest and driest site, while lower dependency was shown in the cooler northern site with higher soil inorganic N content. In both sites, the rate of air temperature increase has been similar in the last decades; however, their soil-plant N dynamics showed different characteristics.
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Affiliation(s)
- Mika Hayashi
- a Faculty of Agriculture , Yamagata University , Tsuruoka , Japan
| | | | - Yoshihiro Nobori
- a Faculty of Agriculture , Yamagata University , Tsuruoka , Japan
| | - Byambasuren Mijidsuren
- b Plant Protection Research Institute , Mongolian University of Life Sciences , Ulaanbaatar , Mongolia
| | - Jens Boy
- c Soil Institute , Leibniz Universität Hannover , Hannover , Germany
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Sterkenburg E, Clemmensen KE, Ekblad A, Finlay RD, Lindahl BD. Contrasting effects of ectomycorrhizal fungi on early and late stage decomposition in a boreal forest. THE ISME JOURNAL 2018; 12:2187-2197. [PMID: 29880913 PMCID: PMC6092328 DOI: 10.1038/s41396-018-0181-2] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 03/20/2018] [Accepted: 04/10/2018] [Indexed: 01/16/2023]
Abstract
Symbiotic ectomycorrhizal fungi have received increasing attention as regulators of below-ground organic matter storage. They are proposed to promote organic matter accumulation by suppressing saprotrophs, but have also been suggested to play an active role in decomposition themselves. Here we show that exclusion of tree roots and associated ectomycorrhizal fungi in a boreal forest increased decomposition of surface litter by 11% by alleviating nitrogen limitation of saprotrophs-a "Gadgil effect". At the same time, root exclusion decreased Mn-peroxidase activity in the deeper mor layer by 91%. Our results show that ectomycorrhizal fungi may hamper short-term litter decomposition, but also support a crucial role of ectomycorrhizal fungi in driving long-term organic matter oxidation. These observations stress the importance of ectomycorrhizal fungi in regulation of below-ground organic matter accumulation. By different mechanisms they may either hamper or stimulate decomposition, depending upon stage of decomposition and location in the soil profile.
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Affiliation(s)
- Erica Sterkenburg
- Swedish University of Agricultural Sciences, Uppsala BioCenter, Department of Forest Mycology and Plant Pathology, Box 7026, SE-750 07, Uppsala, Sweden
| | - Karina E Clemmensen
- Swedish University of Agricultural Sciences, Uppsala BioCenter, Department of Forest Mycology and Plant Pathology, Box 7026, SE-750 07, Uppsala, Sweden
| | - Alf Ekblad
- School of Science and Technology, Örebro University, SE-701 85, Örebro, Sweden
| | - Roger D Finlay
- Swedish University of Agricultural Sciences, Uppsala BioCenter, Department of Forest Mycology and Plant Pathology, Box 7026, SE-750 07, Uppsala, Sweden
| | - Björn D Lindahl
- Swedish University of Agricultural Sciences, Department of Soil and Environment, Box 7014, SE-750 07, Uppsala, Sweden.
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Valiela I, Pascual J, Giblin A, Barth-Jensen C, Martinetto P, Otter M, Stone T, Tucker J, Bartholomew M, Viana IG. External and local controls on land-sea coupling assessed by stable isotopic signatures of mangrove producers in estuaries of Pacific Panama. MARINE ENVIRONMENTAL RESEARCH 2018; 137:133-144. [PMID: 29555298 DOI: 10.1016/j.marenvres.2018.03.003] [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: 01/18/2018] [Revised: 03/05/2018] [Accepted: 03/08/2018] [Indexed: 06/08/2023]
Abstract
Foliar stable isotopic signatures of nitrogen, carbon, and sulfur in mangrove vegetation from the Pacific coast of Panama were insensitive to inputs from watersheds with different area of forest land cover, and to seasonal, inter-annual, and global-scale-driven contrasts in rainfall and upwelling. N, C, and S content of mangrove vegetation were not affected by inputs from watersheds with different degrees of deforestation, but showed some influence of down-estuary transformations. While there was substantial variation that remained un-explained, isotopic signatures and nutrient contents were largely determined by species-specific features, and showed substantial small-scale variation reflecting local differences, within-estuary plant-sediment links. The ability of mangrove estuaries to erase effects of deforestation points out that conservation of these wetland ecosystems is important, because, at least in the sites we studied, transformations within mangrove estuaries were strong enough to protect water quality in receiving coastal waters.
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Affiliation(s)
- Ivan Valiela
- The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA, 02534, United States
| | - Jesús Pascual
- Instituto de Investigaciones Marinas y Costeras, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional de Mar del Plata, CC573, Mar del Plata, Argentina
| | - Anne Giblin
- The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA, 02534, United States
| | - Coralie Barth-Jensen
- The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA, 02534, United States
| | - Paulina Martinetto
- Instituto de Investigaciones Marinas y Costeras, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional de Mar del Plata, CC573, Mar del Plata, Argentina
| | - Marshall Otter
- The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA, 02534, United States
| | - Thomas Stone
- Woods Hole Research Center, Falmouth, MA, 02540, United States
| | - Jane Tucker
- The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA, 02534, United States
| | - Megan Bartholomew
- The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA, 02534, United States
| | - Inés G Viana
- Department of Ecology and Animal Biology, University of Vigo, 36310 Vigo, Galicia, Spain; CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Matosinhos, Portugal.
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40
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Brown JK, Zinnert JC. Mechanisms of surviving burial: Dune grass interspecific differences drive resource allocation after sand deposition. Ecosphere 2018. [DOI: 10.1002/ecs2.2162] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Joseph K. Brown
- Department of Biology Virginia Commonwealth University Richmond Virginia 23284 USA
| | - Julie C. Zinnert
- Department of Biology Virginia Commonwealth University Richmond Virginia 23284 USA
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41
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Chen C, Li J, Wang G, Shi M. Accounting for the effect of temperature in clarifying the response of foliar nitrogen isotope ratios to atmospheric nitrogen deposition. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 609:1295-1302. [PMID: 28793398 DOI: 10.1016/j.scitotenv.2017.06.088] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Revised: 06/10/2017] [Accepted: 06/10/2017] [Indexed: 06/07/2023]
Abstract
Atmospheric nitrogen deposition affects nitrogen isotope composition (δ15N) in plants. However, both negative effect and positive effect have been reported. The effects of climate on plant δ15N have not been corrected for in previous studies, this has impeded discovery of a true effect of atmospheric N deposition on plant δ15N. To obtain a more reliable result, it is necessary to correct for the effects of climatic factors. Here, we measured δ15N and N contents of plants and soils in Baiwangshan and Mount Dongling, north China. Atmospheric N deposition in Baiwangshan was much higher than Mount Dongling. Generally, however, foliar N contents showed no difference between the two regions and foliar δ15N was significantly lower in Baiwangshan than Mount Dongling. The corrected foliar δ15N after accounting for a predicted value assumed to vary with temperature was obviously more negative in Baiwangshan than Mount Dongling. Thus, this suggested the necessity of temperature correction in revealing the effect of N deposition on foliar δ15N. Temperature, soil N sources and mycorrhizal fungi could not explain the difference in foliar δ15N between the two regions, this indicated that atmospheric N deposition had a negative effect on plant δ15N. Additionally, this study also showed that the corrected foliar δ15N of bulk data set increased with altitude above 1300m in Mount Dongling, this provided an another evidence for the conclusion that atmospheric N deposition could cause 15N-depletion in plants.
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Affiliation(s)
- Chongjuan Chen
- Beijing Key Laboratory of Farmland Soil Pollution Prevention-control and Remediation, Department of Environmental Sciences and Engineering, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Jiazhu Li
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing, 100091, China
| | - Guoan Wang
- Beijing Key Laboratory of Farmland Soil Pollution Prevention-control and Remediation, Department of Environmental Sciences and Engineering, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China.
| | - Minrui Shi
- Beijing Key Laboratory of Farmland Soil Pollution Prevention-control and Remediation, Department of Environmental Sciences and Engineering, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
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Barthelemy H, Stark S, Kytöviita M, Olofsson J. Grazing decreases N partitioning among coexisting plant species. Funct Ecol 2017. [DOI: 10.1111/1365-2435.12917] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hélène Barthelemy
- Department of Ecology and Environmental ScienceUmeå University Umeå Sweden
| | - Sari Stark
- Arctic CentreUniversity of Lapland Rovaniemi Finland
| | - Minna‐Maarit Kytöviita
- Department of Biological and Environmental ScienceUniversity of Jyväskylä Jyväskylä Finland
| | - Johan Olofsson
- Department of Ecology and Environmental ScienceUmeå University Umeå Sweden
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Hellmann C, Große-Stoltenberg A, Thiele J, Oldeland J, Werner C. Heterogeneous environments shape invader impacts: integrating environmental, structural and functional effects by isoscapes and remote sensing. Sci Rep 2017; 7:4118. [PMID: 28646189 PMCID: PMC5482842 DOI: 10.1038/s41598-017-04480-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 05/22/2017] [Indexed: 11/19/2022] Open
Abstract
Spatial heterogeneity of ecosystems crucially influences plant performance, while in return plant feedbacks on their environment may increase heterogeneous patterns. This is of particular relevance for exotic plant invaders that transform native ecosystems, yet, approaches integrating geospatial information of environmental heterogeneity and plant-plant interaction are lacking. Here, we combined remotely sensed information of site topography and vegetation cover with a functional tracer of the N cycle, δ15N. Based on the case study of the invasion of an N2-fixing acacia in a nutrient-poor dune ecosystem, we present the first model that can successfully predict (R 2 = 0.6) small-scale spatial variation of foliar δ15N in a non-fixing native species from observed geospatial data. Thereby, the generalized additive mixed model revealed modulating effects of heterogeneous environments on invader impacts. Hence, linking remote sensing techniques with tracers of biological processes will advance our understanding of the dynamics and functioning of spatially structured heterogeneous systems from small to large spatial scales.
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Affiliation(s)
- Christine Hellmann
- Ecosystem Physiology, University of Freiburg, Georges-Köhler-Allee 53/54, 79110, Freiburg, Germany
- Experimental and Systems Ecology, University of Bielefeld, Universitätsstraße 25, 33615, Bielefeld, Germany
| | - André Große-Stoltenberg
- Institute of Landscape Ecology, University of Münster, Heisenbergstraße 2, 48149, Münster, Germany
| | - Jan Thiele
- Institute of Landscape Ecology, University of Münster, Heisenbergstraße 2, 48149, Münster, Germany
| | - Jens Oldeland
- Biodiversity, Ecology and Evolution of Plants, Biocentre Klein Flottbek and Botanical Garden, University of Hamburg, Ohnhorststraße 18, 22609, Hamburg, Germany
| | - Christiane Werner
- Ecosystem Physiology, University of Freiburg, Georges-Köhler-Allee 53/54, 79110, Freiburg, Germany.
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44
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Dawes MA, Schleppi P, Hättenschwiler S, Rixen C, Hagedorn F. Soil warming opens the nitrogen cycle at the alpine treeline. GLOBAL CHANGE BIOLOGY 2017; 23:421-434. [PMID: 27207568 DOI: 10.1111/gcb.13365] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 05/02/2016] [Indexed: 06/05/2023]
Abstract
Climate warming may alter ecosystem nitrogen (N) cycling by accelerating N transformations in the soil, and changes may be especially pronounced in cold regions characterized by N-poor ecosystems. We investigated N dynamics across the plant-soil continuum during 6 years of experimental soil warming (2007-2012; +4 °C) at a Swiss high-elevation treeline site (Stillberg, Davos; 2180 m a.s.l.) featuring Larix decidua and Pinus uncinata. In the soil, we observed considerable increases in the NH4+ pool size in the first years of warming (by >50%), but this effect declined over time. In contrast, dissolved organic nitrogen (DON) concentrations in soil solutions from the organic layer increased under warming, especially in later years (maximum of +45% in 2012), suggesting enhanced DON leaching from the main rooting zone. Throughout the experimental period, foliar N concentrations showed species-specific but small warming effects, whereas δ15 N values showed a sustained increase in warmed plots that was consistent for all species analysed. The estimated total plant N pool size at the end of the study was greater (+17%) in warmed plots with Pinus but not in those containing Larix, with responses driven by trees. Irrespective of plot tree species identity, warming led to an enhanced N pool size of Vaccinium dwarf shrubs, no change in that of Empetrum hermaphroditum (dwarf shrub) and forbs, and a reduction in that of grasses, nonvascular plants, and fine roots. In combination, higher foliar δ15 N values and the transient response in soil inorganic N indicate a persistent increase in plant-available N and greater cumulative plant N uptake in warmer soils. Overall, greater N availability and increased DON concentrations suggest an opening of the N cycle with global warming, which might contribute to growth stimulation of some plant species while simultaneously leading to greater N losses from treeline ecosystems and possibly other cold biomes.
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Affiliation(s)
- Melissa A Dawes
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, CH-8903, Birmensdorf, Switzerland
- WSL Institute for Snow and Avalanche Research - SLF, Flüelastrasse 11, CH-7260, Davos Dorf, Switzerland
| | - Patrick Schleppi
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, CH-8903, Birmensdorf, Switzerland
| | - Stephan Hättenschwiler
- Centre d'Ecologie Fonctionnelle & Evolutive (CEFE UMR 5175), CNRS - Université de Montpellier - Université Paul-Valéry Montpellier - EPHE, 1919 route de Mende, F-34293, Montpellier Cedex 5, France
| | - Christian Rixen
- WSL Institute for Snow and Avalanche Research - SLF, Flüelastrasse 11, CH-7260, Davos Dorf, Switzerland
| | - Frank Hagedorn
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, CH-8903, Birmensdorf, Switzerland
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45
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Chen J, Hofmockel KS, Hobbie EA. Isotopic Analysis of Sporocarp Protein and Structural Material Improves Resolution of Fungal Carbon Sources. Front Microbiol 2016; 7:1994. [PMID: 28082951 PMCID: PMC5183622 DOI: 10.3389/fmicb.2016.01994] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 11/28/2016] [Indexed: 11/13/2022] Open
Abstract
Fungal acquisition of resources is difficult to assess in the field. To determine whether fungi received carbon from recent plant photosynthate, litter or soil-derived organic (C:N bonded) nitrogen, we examined differences in δ13C among bulk tissue, structural carbon, and protein extracts of sporocarps of three fungal types: saprotrophic fungi, fungi with hydrophobic ectomycorrhizae, or fungi with hydrophilic ectomycorrhizae. Sporocarps were collected from experimental plots of the Duke Free-air CO2 enrichment experiment during and after CO2 enrichment. The differential 13C labeling of ecosystem pools in CO2 enrichment experiments was tracked into fungi and provided novel insights into organic nitrogen use. Specifically, sporocarp δ13C as well as δ15N of protein and structural material indicated that fungi with hydrophobic ectomycorrhizae used soil-derived organic nitrogen sources for protein carbon, fungi with hydrophilic ectomycorrhizae used recent plant photosynthates for protein carbon and both fungal groups used photosynthates for structural carbon. Saprotrophic fungi depended on litter produced during fumigation for both protein and structural material.
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Affiliation(s)
- Janet Chen
- Earth, Oceans and Space, Earth Systems Research Center, University of New HampshireDurham, NH, USA
- Soil and Water Management and Crop Nutrition Laboratory, FAO/IAEA Agriculture and Biotechnology LaboratoriesSeibersdorf, Austria
| | - Kirsten S. Hofmockel
- Department of Ecology, Evolution and Organismal Biology, Iowa State UniversityAmes, IA, USA
- Environmental Molecular Sciences Laboratory and Biological Sciences Division, Pacific Northwest National LaboratoryRichland, WA, USA
| | - Erik A. Hobbie
- Earth, Oceans and Space, Earth Systems Research Center, University of New HampshireDurham, NH, USA
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Ruiz-Navarro A, Barberá GG, Albaladejo J, Querejeta JI. Plant δ 15 N reflects the high landscape-scale heterogeneity of soil fertility and vegetation productivity in a Mediterranean semiarid ecosystem. THE NEW PHYTOLOGIST 2016; 212:1030-1043. [PMID: 27405992 DOI: 10.1111/nph.14091] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 06/05/2016] [Indexed: 06/06/2023]
Abstract
We investigated the magnitude and drivers of spatial variability in soil and plant δ15 N across the landscape in a topographically complex semiarid ecosystem. We hypothesized that large spatial heterogeneity in water availability, soil fertility and vegetation cover would be positively linked to high local-scale variability in δ15 N. We measured foliar δ15 N in three dominant plant species representing contrasting plant functional types (tree, shrub, grass) and mycorrhizal association types (ectomycorrhizal or arbuscular mycorrhizal). This allowed us to investigate whether δ15 N responds to landscape-scale environmental heterogeneity in a consistent way across species. Leaf δ15 N varied greatly within species across the landscape and was strongly spatially correlated among co-occurring individuals of the three species. Plant δ15 N correlated tightly with soil δ15 N and key measures of soil fertility, water availability and vegetation productivity, including soil nitrogen (N), organic carbon (C), plant-available phosphorus (P), water-holding capacity, topographic moisture indices and normalized difference vegetation index. Multiple regression models accounted for 62-83% of within-species variation in δ15 N across the landscape. The tight spatial coupling and interdependence of the water, N and C cycles in drylands may allow the use of leaf δ15 N as an integrative measure of variations in moisture availability, biogeochemical activity, soil fertility and vegetation productivity (or 'site quality') across the landscape.
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Affiliation(s)
- Antonio Ruiz-Navarro
- Department of Soil and Water Conservation, Spanish National Research Council (CEBAS-CSIC), PO Box 164, Campus Universitario de Espinardo, Espinardo, Murcia, E-30100, Spain
| | - Gonzalo G Barberá
- Department of Soil and Water Conservation, Spanish National Research Council (CEBAS-CSIC), PO Box 164, Campus Universitario de Espinardo, Espinardo, Murcia, E-30100, Spain
| | - Juan Albaladejo
- Department of Soil and Water Conservation, Spanish National Research Council (CEBAS-CSIC), PO Box 164, Campus Universitario de Espinardo, Espinardo, Murcia, E-30100, Spain
| | - José I Querejeta
- Department of Soil and Water Conservation, Spanish National Research Council (CEBAS-CSIC), PO Box 164, Campus Universitario de Espinardo, Espinardo, Murcia, E-30100, Spain
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47
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Schweiger PF. Nitrogen isotope fractionation during N uptake via arbuscular mycorrhizal and ectomycorrhizal fungi into grey alder. JOURNAL OF PLANT PHYSIOLOGY 2016; 205:84-92. [PMID: 27639038 DOI: 10.1016/j.jplph.2016.08.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 08/11/2016] [Accepted: 08/12/2016] [Indexed: 06/06/2023]
Abstract
Arbuscular mycorrhizal (AM) and ectomycorrhizal (ECM) fungi affect plant nitrogen (N) dynamics. Plant N isotope patterns have been used to characterise the contribution of ECM fungi to plant N uptake. By quantifying and comparing the effects of an AM and an ECM fungus on growth, N uptake and isotopic composition of one host plant grown at different relative N supply levels, the aim of this study was to improve the mechanistic understanding of natural 15N abundance patterns in mycorrhizal plants and their underlying causes. Grey alders were inoculated with one ECM fungus or one AM fungus or left non-mycorrhizal. Plants were grown under semi-hydroponic conditions and were supplied with three rates of relative N supply ranging from deficient to luxurious. Neither mycorrhizal fungus increased plant growth or N uptake. AM root colonisation had no effect on whole plant δ15N and decreased foliar δ 15N only under N deficiency. The roots of these plants were 15N-enriched. ECM root colonisation consistently decreased foliar and whole plant δ15N. It is concluded, that both mycorrhizal fungi contributed to plant N uptake into the shoot. Nitrogen isotope fractionation during N assimilation and transformations in fungal mycelia is suggested to have resulted in plants receiving 15N-depleted N via the mycorrhizal uptake pathways. Negative mycorrhizal growth effects are explained by symbiotic resource trade on carbon and N and decreased direct plant N uptake.
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Affiliation(s)
- Peter F Schweiger
- Department of Microbiology and Ecosystem Science, Division of Terrestrial Ecosystem Research, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria.
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48
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Thirkell TJ, Cameron DD, Hodge A. Resolving the 'nitrogen paradox' of arbuscular mycorrhizas: fertilization with organic matter brings considerable benefits for plant nutrition and growth. PLANT, CELL & ENVIRONMENT 2016; 39:1683-90. [PMID: 26510552 PMCID: PMC4982020 DOI: 10.1111/pce.12667] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 10/05/2015] [Indexed: 05/08/2023]
Abstract
Arbuscular mycorrhizal fungi (AMF) can transfer nitrogen (N) to host plants, but the ecological relevance is debated, as total plant N and biomass do not generally increase. The extent to which the symbiosis is mutually beneficial is thought to rely on the stoichiometry of N, phosphorus (P) and carbon (C) availability. While inorganic N fertilization has been shown to elicit strong mutualism, characterized by improved plant and fungal growth and mineral nutrition, similar responses following organic N addition are lacking. Using a compartmented microcosm experiment, we determined the significance to a mycorrhizal plant of placing a (15) N-labelled, nitrogen-rich patch of organic matter in a compartment to which only AMF hyphae had access. Control microcosms denied AMF hyphal access to the patch compartment. When permitted access to the patch compartment, the fungus proliferated extensively in the patch and transferred substantial quantities of N to the plant. Moreover, our data demonstrate that allowing hyphal access to an organic matter patch enhanced total plant N and P contents, with a simultaneous and substantial increase in plant biomass. Furthermore, we demonstrate that organic matter fertilization of arbuscular mycorrhizal plants can foster a mutually beneficial symbiosis based on nitrogen transfer, a phenomenon previously thought irrelevant.
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Affiliation(s)
- Tom J Thirkell
- Department of Biology, University of York, Wentworth Way, York, YO10 5DD, UK
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
| | - Duncan D Cameron
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
| | - Angela Hodge
- Department of Biology, University of York, Wentworth Way, York, YO10 5DD, UK
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Salmon VG, Soucy P, Mauritz M, Celis G, Natali SM, Mack MC, Schuur EAG. Nitrogen availability increases in a tundra ecosystem during five years of experimental permafrost thaw. GLOBAL CHANGE BIOLOGY 2016; 22:1927-1941. [PMID: 26718892 DOI: 10.1111/gcb.13204] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 11/19/2015] [Accepted: 12/01/2015] [Indexed: 06/05/2023]
Abstract
Perennially frozen soil in high latitude ecosystems (permafrost) currently stores 1330-1580 Pg of carbon (C). As these ecosystems warm, the thaw and decomposition of permafrost is expected to release large amounts of C to the atmosphere. Fortunately, losses from the permafrost C pool will be partially offset by increased plant productivity. The degree to which plants are able to sequester C, however, will be determined by changing nitrogen (N) availability in these thawing soil profiles. N availability currently limits plant productivity in tundra ecosystems but plant access to N is expected improve as decomposition increases in speed and extends to deeper soil horizons. To evaluate the relationship between permafrost thaw and N availability, we monitored N cycling during 5 years of experimentally induced permafrost thaw at the Carbon in Permafrost Experimental Heating Research (CiPEHR) project. Inorganic N availability increased significantly in response to deeper thaw and greater soil moisture induced by Soil warming. This treatment also prompted a 23% increase in aboveground biomass and a 49% increase in foliar N pools. The sedge Eriophorum vaginatum responded most strongly to warming: this species explained 91% of the change in aboveground biomass during the 5 year period. Air warming had little impact when applied alone, but when applied in combination with Soil warming, growing season soil inorganic N availability was significantly reduced. These results demonstrate that there is a strong positive relationship between the depth of permafrost thaw and N availability in tundra ecosystems but that this relationship can be diminished by interactions between increased thaw, warmer air temperatures, and higher levels of soil moisture. Within 5 years of permafrost thaw, plants actively incorporate newly available N into biomass but C storage in live vascular plant biomass is unlikely to be greater than losses from deep soil C pools.
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Affiliation(s)
- Verity G Salmon
- Biology Department, University of Florida, Gainesville, FL, 32611, USA
| | - Patrick Soucy
- Biology Department, University of Florida, Gainesville, FL, 32611, USA
| | - Marguerite Mauritz
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Gerardo Celis
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | | | - Michelle C Mack
- Biology Department, University of Florida, Gainesville, FL, 32611, USA
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Edward A G Schuur
- Biology Department, University of Florida, Gainesville, FL, 32611, USA
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, 86011, USA
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Corrales A, Mangan SA, Turner BL, Dalling JW. An ectomycorrhizal nitrogen economy facilitates monodominance in a neotropical forest. Ecol Lett 2016; 19:383-92. [DOI: 10.1111/ele.12570] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 10/16/2015] [Accepted: 12/14/2015] [Indexed: 11/28/2022]
Affiliation(s)
- Adriana Corrales
- Department of Plant Biology University of Illinois at Urbana‐Champaign Urbana‐Champaign IL 61801 USA
| | - Scott A. Mangan
- Department of Biology Washington University in St. Louis St. Louis MO 63130 USA
- Smithsonian Tropical Research Institute Apartado 0843–03092 Balboa Ancon Panama
| | - Benjamin L. Turner
- Smithsonian Tropical Research Institute Apartado 0843–03092 Balboa Ancon Panama
| | - James W. Dalling
- Department of Plant Biology University of Illinois at Urbana‐Champaign Urbana‐Champaign IL 61801 USA
- Smithsonian Tropical Research Institute Apartado 0843–03092 Balboa Ancon Panama
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