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Nadal M, Peguero‐Pina JJ, Sancho‐Knapik D, Gil‐Pelegrín E. Comparison of different methods to evaluate tissue damage in response to leaf dehydration in Quercus ilex L. and Q. faginea Lam. PHYSIOLOGIA PLANTARUM 2025; 177:e70178. [PMID: 40128144 PMCID: PMC11932967 DOI: 10.1111/ppl.70178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2024] [Revised: 02/25/2025] [Accepted: 03/04/2025] [Indexed: 03/26/2025]
Abstract
Determination of the point of critical damage in plant organs is crucial to elucidate the causes of plant mortality, but the different methodologies to quantify such damage have not been previously compared under the same experimental conditions. Here, we tested different indicators to evaluate damage in leaves of Quercus faginea and Q. ilex; in the latter case, 1- and 2-year-old leaves were included. The damage indicators were relative electrolyte leakage (REL), rehydration capacity (evaluated as the percentage loss of rehydration capacity; PLRC), chlorophyll fluorescence (maximum quantum yield of PSII; Fv/Fm), and the viability marker triphenyltetrazolium chloride (TTC). These damage indicators were evaluated in different sets of detached leaves for each species and leaf age dehydrated on the lab bench. Electrolyte leakage and PLRC showed a gradual response to decreasing relative water content, whereas Fv/Fm and TTC showed a threshold-like response, especially in the case of Q. faginea. Electrolyte leakage and TTC did not show differences between species and/or leaf ages. Measurement of Fv/Fm in dehydrating leaves proved to be the most straightforward, rapid and precise method for damage quantification, allowing for the differentiation in dehydration tolerance between Q. ilex and Q. faginea.
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Affiliation(s)
- Miquel Nadal
- Université de Lorraine, AgroParisTech, INRAE, UMR SilvaNancyFrance
- Departamento de Sistemas Agrícolas, Forestales y Medio AmbienteCentro de Investigación y Tecnología Agroalimentaria de Aragón (CITA)ZaragozaSpain
| | - José Javier Peguero‐Pina
- Departamento de Sistemas Agrícolas, Forestales y Medio AmbienteCentro de Investigación y Tecnología Agroalimentaria de Aragón (CITA)ZaragozaSpain
- Instituto Agroalimentario de Aragón ‐IA2‐ (CITA‐Universidad de Zaragoza)ZaragozaSpain
| | - Domingo Sancho‐Knapik
- Departamento de Sistemas Agrícolas, Forestales y Medio AmbienteCentro de Investigación y Tecnología Agroalimentaria de Aragón (CITA)ZaragozaSpain
- Instituto Agroalimentario de Aragón ‐IA2‐ (CITA‐Universidad de Zaragoza)ZaragozaSpain
| | - Eustaquio Gil‐Pelegrín
- Estación Experimental de Aula Dei (EEAD)Consejo Superior de Investigaciones Científicas (CSIC)ZaragozaSpain
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2
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Liu J, Huang J, Peng S, Xiong D. Rewatering after drought: Unravelling the drought thresholds and function recovery-limiting factors in maize leaves. PLANT, CELL & ENVIRONMENT 2024; 47:5457-5469. [PMID: 39205650 DOI: 10.1111/pce.15080] [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: 02/06/2024] [Revised: 07/05/2024] [Accepted: 07/30/2024] [Indexed: 09/04/2024]
Abstract
Drought and subsequent rewatering are common in agriculture, where recovery from mild droughts is easier than from severe ones. The specific drought threshold and factors limiting recovery are under-researched. This study subjected maize plants to varying drought degrees before rewatering, and measuring plant water status, gas exchange, hydraulic conductance, hormone levels, and cellular damage throughout. We discovered that stomatal reopening in plants was inhibited with leaf water potentials below about -1.7 MPa, hindering postdrought photosynthetic recovery. Neither hydraulic loss nor abscisic acid (ABA) content was the factor inhibited stomatal reopening on the second day following moderate drought stress and rewatering. But stomatal reopening was significantly correlated to the interaction between hydraulic signals and ABA content under severe drought. Extended drought led to leaf death at about -2.8 MPa or 57% relative water content, influenced by reduced rehydration capacity, not hydraulic failure. The lethal threshold remained relatively constant across leaf stages, but the recoverable safety margin (RSM), that is, the water potential difference between stomatal closure and recovery capacity loss, significantly decreased with leaf aging due to delayed stomatal closure during drought. Our findings indicate hydraulic failure alone does not cause maize leaf death, highlighting the importance of RSM in future research.
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Affiliation(s)
- Junzhou Liu
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, MARA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Jianliang Huang
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, MARA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Shaobing Peng
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, MARA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Dongliang Xiong
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, MARA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Huazhong Agricultural University, Wuhan, Hubei, China
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3
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Alon A, Cohen S, Burlett R, Eselson E, Riov J, Delzon S, David-Schwartz R. Leaf membrane leakage and xylem hydraulic failure define the point of no return in drought-induced tree mortality in Cupressus sempervirens. PHYSIOLOGIA PLANTARUM 2024; 176:e14467. [PMID: 39140130 DOI: 10.1111/ppl.14467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 07/03/2024] [Accepted: 07/08/2024] [Indexed: 08/15/2024]
Abstract
Measurements of resistance to embolism suggest that Cupressus sempervirens has a stem xylem that resists embolism at very negative water potentials, with 50% embolism (P50) at water potentials of approximately -10 MPa. However, field observations in a semi-arid region suggest tree mortality occurs before 10% embolism. To explore the interplay between embolism and plant mortality, we conducted a controlled drought experiment involving two types of CS seedlings: a local seed source (S-type) and a drought-resistant clone propagated from a semi-arid forest (C-type). We measured resistance to embolism, leaf relative water content (RWC), water potential, photosynthesis, electrolyte leakage (EL), plant water loss, leaf hydraulic conductivity, and leaf non-structural carbohydrate (NSC) content during plant dehydration and before rewatering. All measured individuals were monitored for survival or mortality. While the S- and C-types differed in P50, transpiration, and mortality rates, both displayed seedling mortality corresponding to threshold values of 52-55% leaf RWC, 55% and 18.5% percent loss of conductivity (PLC) in the xylem, which corresponds to 48% and 37% average EL values for S and C types, respectively. Although C-type C. sempervirens NSC content increased in response to drought, no differences were observed in NSC content between live and dead seedlings of both types. Our findings do not fully explain tree mortality in the field but they do indicate that loss of membrane integrity occurs before or at xylem water potential, leading to hydraulic failure.
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Affiliation(s)
- Asaf Alon
- Institute of Plant Sciences, Volcani Center, Agricultural Research Organization, Rishon LeZion, Israel
- Institute of Soil, Water and Environmental Sciences, Volcani Center, Agricultural Research Organization, Rishon LeZion, Israel
- Institute of Plant Sciences and Genetics in Agriculture, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Shabtai Cohen
- Institute of Soil, Water and Environmental Sciences, Volcani Center, Agricultural Research Organization, Rishon LeZion, Israel
| | | | - Elena Eselson
- Institute of Plant Sciences, Volcani Center, Agricultural Research Organization, Rishon LeZion, Israel
| | - Joseph Riov
- Institute of Plant Sciences and Genetics in Agriculture, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | | | - Rakefet David-Schwartz
- Institute of Plant Sciences, Volcani Center, Agricultural Research Organization, Rishon LeZion, Israel
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Paligi SS, Lichter J, Kotowska M, Schwutke RL, Audisio M, Mrak K, Penanhoat A, Schuldt B, Hertel D, Leuschner C. Water status dynamics and drought tolerance of juvenile European beech, Douglas fir and Norway spruce trees as dependent on neighborhood and nitrogen supply. TREE PHYSIOLOGY 2024; 44:tpae044. [PMID: 38662576 DOI: 10.1093/treephys/tpae044] [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: 10/09/2023] [Accepted: 04/14/2024] [Indexed: 05/31/2024]
Abstract
To increase the resilience of forests to drought and other hazards, foresters are increasingly planting mixed stands. This requires knowledge about the drought response of tree species in pure and mixed-culture neighborhoods. In addition, drought frequently interacts with continued atmospheric nitrogen (N) deposition. To disentangle these factors for European beech, Norway spruce and Douglas fir, we conducted a replicated 3-factorial sapling growth experiment with three moisture levels, (high, medium, and low), two N levels (high and ambient), and pure and mixed-culture neighborhoods. We measured biomass, stomatal conductance (GS), shoot water potential (at predawn: ΨPD, midday, and turgor loss point: ΨTLP), branch xylem embolism resistance (Ψ50) and minimum epidermal conductance (Gmin). The three species differed most with respect to Gmin (10-fold higher in beech than in the conifers), hydroscape area (larger in beech), and the time elapsed to reach stomatal closure (TΨGS90) and ΨTLP (TTLP; shorter in beech), while Ψ50 and ΨTLP were remarkably similar. Neighborhood (pure vs mixed-culture) influenced biomass production, water status and hydraulic traits, notably GS (higher in Douglas fir, but lower in spruce and beech, in mixtures than pure culture), hydraulic safety margin (smaller for beech in mixtures), and TΨGS90 and TTLP (shorter for spruce in mixture). High N generally increased GS, but no consistent N effects on leaf water status and hydraulic traits were detected, suggesting that neighbor identity had a larger effect on plant water relations than N availability. We conclude that both tree neighborhood and N availability modulate the drought response of beech, spruce, and Douglas fir. Species mixing can alleviate the drought stress of some species, but often by disadvantaging other species. Thus, our study suggests that stabilizing and building resilience of production forests against a drier and warmer climate may depend primarily on the right species choice; species mixing can support the agenda.
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Affiliation(s)
- Sharath S Paligi
- Plant Ecology and Ecosystems Research, Albrecht von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, 37073 Goettingen, Germany
| | - Jens Lichter
- Chair of Statistics, University of Goettingen, Humboldtallee 3, 37073 Goettingen, Germany
| | - Martyna Kotowska
- Plant Ecology and Ecosystems Research, Albrecht von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, 37073 Goettingen, Germany
- School of Natural Sciences, Wallumattagal Campus, Macquarie University, 4-6 Eastern Road Macquarie Park NSW 2109, Sydney, Australia
| | - Rebecca L Schwutke
- Plant Ecology and Ecosystems Research, Albrecht von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, 37073 Goettingen, Germany
| | - Michela Audisio
- Forest Botany and Tree Physiology, University of Goettingen, Büsgenweg 2, D-37077 Goettingen, Germany
| | - Klara Mrak
- Soil Science of Temperate Ecosystems, University of Goettingen, Büsgenweg 2, D-37077 Göttingen, Germany
| | - Alice Penanhoat
- Department of Spatial Structures and Digitization of Forests, University of Goettingen, Büsgenweg 1, 37077 Goettingen, Germany
| | - Bernhard Schuldt
- Chair of Forest Botany, Institute of Forest Botany and Forest Zoology, Technical University of Dresden, Pienner Street 7, 01737 Tharandt, Germany
| | - Dietrich Hertel
- Plant Ecology and Ecosystems Research, Albrecht von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, 37073 Goettingen, Germany
| | - Christoph Leuschner
- Plant Ecology and Ecosystems Research, Albrecht von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, 37073 Goettingen, Germany
- Centre for Biodiversity and Sustainable Land Use (CBL), University of Goettingen, 37075 Goettingen, Germany
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5
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Castillo-Argaez R, Sapes G, Mallen N, Lippert A, John GP, Zare A, Hammond WM. Spectral ecophysiology: hyperspectral pressure-volume curves to estimate leaf turgor loss. THE NEW PHYTOLOGIST 2024; 242:935-946. [PMID: 38482720 DOI: 10.1111/nph.19669] [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: 11/28/2023] [Accepted: 02/19/2024] [Indexed: 04/12/2024]
Abstract
Turgor loss point (TLP) is an important proxy for plant drought tolerance, species habitat suitability, and drought-induced plant mortality risk. Thus, TLP serves as a critical tool for evaluating climate change impacts on plants, making it imperative to develop high-throughput and in situ methods to measure TLP. We developed hyperspectral pressure-volume curves (PV curves) to estimate TLP using leaf spectral reflectance. We used partial least square regression models to estimate water potential (Ψ) and relative water content (RWC) for two species, Frangula caroliniana and Magnolia grandiflora. RWC and Ψ's model for each species had R2 ≥ 0.7 and %RMSE = 7-10. We constructed PV curves with model estimates and compared the accuracy of directly measured and spectra-predicted TLP. Our findings indicate that leaf spectral measurements are an alternative method for estimating TLP. F. caroliniana TLP's values were -1.62 ± 0.15 (means ± SD) and -1.62 ± 0.34 MPa for observed and reflectance predicted, respectively (P > 0.05), while M. grandiflora were -1.78 ± 0.34 and -1.66 ± 0.41 MPa (P > 0.05). The estimation of TLP through leaf reflectance-based PV curves opens a broad range of possibilities for future research aimed at understanding and monitoring plant water relations on a large scale with spectral ecophysiology.
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Affiliation(s)
| | - Gerard Sapes
- Agronomy Department, University of Florida, Gainesville, FL, 32611, USA
| | - Nicole Mallen
- Agronomy Department, University of Florida, Gainesville, FL, 32611, USA
| | - Alston Lippert
- Agronomy Department, University of Florida, Gainesville, FL, 32611, USA
| | - Grace P John
- Department of Biology, University of Florida, Gainesville, FL, 32611, USA
| | - Alina Zare
- Department of Electrical and Computer Engineering, University of Florida, Gainesville, FL, 32611, USA
| | - William M Hammond
- Agronomy Department, University of Florida, Gainesville, FL, 32611, USA
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6
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Andriantelomanana T, Améglio T, Delzon S, Cochard H, Herbette S. Unpacking the point of no return under drought in poplar: insight from stem diameter variation. THE NEW PHYTOLOGIST 2024; 242:466-478. [PMID: 38406847 DOI: 10.1111/nph.19615] [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: 11/15/2023] [Accepted: 02/02/2024] [Indexed: 02/27/2024]
Abstract
A specific, robust threshold for drought-induced tree mortality is needed to improve the prediction of forest dieback. Here, we tested the relevance of continuous measurements of stem diameter variations for identifying such a threshold, their relationship with hydraulic and cellular damage mechanisms, and the influence of growth conditions on these relationships. Poplar saplings were grown under well-watered, water-limited, or light-limited conditions and then submitted to a drought followed by rewatering. Stem diameter was continuously measured to investigate two parameters: the percentage loss of diameter (PLD) and the percentage of diameter recovery (DR) following rewatering. Water potentials, stomatal conductance, embolism, and electrolyte leakage were also measured, and light microscopy allowed investigating cell collapse induced by drought. The water release observed through loss of diameter occurred throughout the drought, regardless of growth conditions. Poplars did not recover from drought when PLD reached a threshold and this differed according to growth conditions but remained linked to cell resistance to damage and collapse. Our findings shed new light on the mechanisms of drought-induced tree mortality and indicate that PLD could be a relevant indicator of drought-induced tree mortality, regardless of the growth conditions.
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Affiliation(s)
| | - Thierry Améglio
- Université Clermont Auvergne, INRAE, PIAF, Clermont-Ferrand, 63000, France
| | - Sylvain Delzon
- Université Bordeaux, INRAE, BIOGECO, Pessac, 33615, France
| | - Hervé Cochard
- Université Clermont Auvergne, INRAE, PIAF, Clermont-Ferrand, 63000, France
| | - Stephane Herbette
- Université Clermont Auvergne, INRAE, PIAF, Clermont-Ferrand, 63000, France
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7
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Sapes G, Schroeder L, Scott A, Clark I, Juzwik J, Montgomery RA, Guzmán Q JA, Cavender-Bares J. Mechanistic links between physiology and spectral reflectance enable previsual detection of oak wilt and drought stress. Proc Natl Acad Sci U S A 2024; 121:e2316164121. [PMID: 38315867 PMCID: PMC10873599 DOI: 10.1073/pnas.2316164121] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Accepted: 12/11/2023] [Indexed: 02/07/2024] Open
Abstract
Tree mortality due to global change-including range expansion of invasive pests and pathogens-is a paramount threat to forest ecosystems. Oak forests are among the most prevalent and valuable ecosystems both ecologically and economically in the United States. There is increasing interest in monitoring oak decline and death due to both drought and the oak wilt pathogen (Bretziella fagacearum). We combined anatomical and ecophysiological measurements with spectroscopy at leaf, canopy, and airborne levels to enable differentiation of oak wilt and drought, and detection prior to visible symptom appearance. We performed an outdoor potted experiment with Quercus rubra saplings subjected to drought stress and/or artificially inoculated with the pathogen. Models developed from spectral reflectance accurately predicted ecophysiological indicators of oak wilt and drought decline in both potted and field experiments with naturally grown saplings. Both oak wilt and drought resulted in blocked water transport through xylem conduits. However, oak wilt impaired conduits in localized regions of the xylem due to formation of tyloses instead of emboli. The localized tylose formation resulted in more variable canopy photosynthesis and water content in diseased trees than drought-stressed ones. Reflectance signatures of plant photosynthesis, water content, and cellular damage detected oak wilt and drought 12 d before visual symptoms appeared. Our results show that leaf spectral reflectance models predict ecophysiological processes relevant to detection and differentiation of disease and drought. Coupling spectral models that detect physiological change with spatial information enhances capacity to differentiate plant stress types such as oak wilt and drought.
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Affiliation(s)
- Gerard Sapes
- Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, MN55108
- Agronomy Department, University of Florida, Gainesville, FL32611
| | - Lucy Schroeder
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, MN55108
| | - Allison Scott
- Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, MN55108
| | - Isaiah Clark
- Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, MN55108
| | - Jennifer Juzwik
- Northern Research Station, United States Department of Agriculture Forest Service, St. Paul, MN55108
| | | | - J. Antonio Guzmán Q
- Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, MN55108
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Torres-Ruiz JM, Cochard H, Delzon S, Boivin T, Burlett R, Cailleret M, Corso D, Delmas CEL, De Caceres M, Diaz-Espejo A, Fernández-Conradi P, Guillemot J, Lamarque LJ, Limousin JM, Mantova M, Mencuccini M, Morin X, Pimont F, De Dios VR, Ruffault J, Trueba S, Martin-StPaul NK. Plant hydraulics at the heart of plant, crops and ecosystem functions in the face of climate change. THE NEW PHYTOLOGIST 2024; 241:984-999. [PMID: 38098153 DOI: 10.1111/nph.19463] [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: 07/04/2023] [Accepted: 11/05/2023] [Indexed: 01/12/2024]
Abstract
Plant hydraulics is crucial for assessing the plants' capacity to extract and transport water from the soil up to their aerial organs. Along with their capacity to exchange water between plant compartments and regulate evaporation, hydraulic properties determine plant water relations, water status and susceptibility to pathogen attacks. Consequently, any variation in the hydraulic characteristics of plants is likely to significantly impact various mechanisms and processes related to plant growth, survival and production, as well as the risk of biotic attacks and forest fire behaviour. However, the integration of hydraulic traits into disciplines such as plant pathology, entomology, fire ecology or agriculture can be significantly improved. This review examines how plant hydraulics can provide new insights into our understanding of these processes, including modelling processes of vegetation dynamics, illuminating numerous perspectives for assessing the consequences of climate change on forest and agronomic systems, and addressing unanswered questions across multiple areas of knowledge.
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Affiliation(s)
- José M Torres-Ruiz
- Université Clermont-Auvergne, INRAE, PIAF, 63000, Clermont-Ferrand, France
| | - Hervé Cochard
- Université Clermont-Auvergne, INRAE, PIAF, 63000, Clermont-Ferrand, France
| | - Sylvain Delzon
- University of Bordeaux, INRAE, UMR BIOGECO, Pessac, 33615, France
| | | | - Regis Burlett
- University of Bordeaux, INRAE, UMR BIOGECO, Pessac, 33615, France
| | - Maxime Cailleret
- INRAE, Aix-Marseille Université, UMR RECOVER, Aix-en-Provence, 13100, France
| | - Déborah Corso
- University of Bordeaux, INRAE, UMR BIOGECO, Pessac, 33615, France
| | - Chloé E L Delmas
- INRAE, Bordeaux Sciences Agro, ISVV, SAVE, F-33140, Villenave d'Ornon, France
| | | | - Antonio Diaz-Espejo
- Instituto de Recursos Naturales y Agrobiología (IRNAS), Consejo Superior de Investigaciones Científicas (CSIC), Seville, 41012, Spain
| | | | - Joannes Guillemot
- CIRAD, UMR Eco&Sols, Montpellier, 34394, France
- Eco&Sols, Univ. Montpellier, CIRAD, INRAe, Institut Agro, IRD, Montpellier, 34394, France
- Department of Forest Sciences, ESALQ, University of São Paulo, Piracicaba, 05508-060, São Paulo, Brazil
| | - Laurent J Lamarque
- Département des sciences de l'environnement, Université du Québec à Trois-Rivières, Trois-Rivières, G9A 5H7, Québec, Canada
| | | | - Marylou Mantova
- Agronomy Department, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, 32611, USA
| | - Maurizio Mencuccini
- CREAF, Bellaterra (Cerdanyola del Vallès), Catalonia, E08193, Spain
- ICREA, Barcelona, 08010, Spain
| | - Xavier Morin
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, 34394, France
| | | | - Victor Resco De Dios
- Department of Forest and Agricultural Science and Engineering, University of Lleida, Lleida, 25198, Spain
- JRU CTFC-AGROTECNIO-CERCA Center, Lleida, 25198, Spain
| | | | - Santiago Trueba
- University of Bordeaux, INRAE, UMR BIOGECO, Pessac, 33615, France
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Li X, Ma Z, Song Y, Shen W, Yue Q, Khan A, Tahir MM, Wang X, Malnoy M, Ma F, Bus V, Zhou S, Guan Q. Insights into the molecular mechanisms underlying responses of apple trees to abiotic stresses. HORTICULTURE RESEARCH 2023; 10:uhad144. [PMID: 37575656 PMCID: PMC10421731 DOI: 10.1093/hr/uhad144] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 07/13/2023] [Indexed: 08/15/2023]
Abstract
Apple (Malus[Formula: see text]domestica) is a popular temperate fruit crop worldwide. However, its growth, productivity, and quality are often adversely affected by abiotic stresses such as drought, extreme temperature, and high salinity. Due to the long juvenile phase and highly heterozygous genome, the conventional breeding approaches for stress-tolerant cultivars are time-consuming and resource-intensive. These issues may be resolved by feasible molecular breeding techniques for apples, such as gene editing and marker-assisted selection. Therefore, it is necessary to acquire a more comprehensive comprehension of the molecular mechanisms underpinning apples' response to abiotic stress. In this review, we summarize the latest research progress in the molecular response of apples to abiotic stressors, including the gene expression regulation, protein modifications, and epigenetic modifications. We also provide updates on new approaches for improving apple abiotic stress tolerance, while discussing current challenges and future perspectives for apple molecular breeding.
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Affiliation(s)
- Xuewei Li
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Ziqing Ma
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yi Song
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Wenyun Shen
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Qianyu Yue
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Abid Khan
- Department of Horticulture, The University of Haripur, Haripur 22620, Pakistan
| | - Muhammad Mobeen Tahir
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xiaofei Wang
- State Key Laboratory of Crop Biology, Shandong Collaborative Innovation Center for Fruit and Vegetable Production with High Quality and Efficiency, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271000, China
| | - Mickael Malnoy
- Research and Innovation Centre, Fondazione Edmund Mach, San Michele all’Adige 38098, Italy
| | - Fengwang Ma
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Vincent Bus
- The New Zealand Institute for Plant and Food Research Limited, Havelock North 4157, New Zealand
| | - Shuangxi Zhou
- Department of Biological Sciences, Macquarie University, North Ryde, NSW 2109, Australia
| | - Qingmei Guan
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
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10
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Peters RL, Steppe K, Pappas C, Zweifel R, Babst F, Dietrich L, von Arx G, Poyatos R, Fonti M, Fonti P, Grossiord C, Gharun M, Buchmann N, Steger DN, Kahmen A. Daytime stomatal regulation in mature temperate trees prioritizes stem rehydration at night. THE NEW PHYTOLOGIST 2023. [PMID: 37235688 DOI: 10.1111/nph.18964] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 04/16/2023] [Indexed: 05/28/2023]
Abstract
Trees remain sufficiently hydrated during drought by closing stomata and reducing canopy conductance (Gc ) in response to variations in atmospheric water demand and soil water availability. Thresholds that control the reduction of Gc are proposed to optimize hydraulic safety against carbon assimilation efficiency. However, the link between Gc and the ability of stem tissues to rehydrate at night remains unclear. We investigated whether species-specific Gc responses aim to prevent branch embolisms, or enable night-time stem rehydration, which is critical for turgor-dependent growth. For this, we used a unique combination of concurrent dendrometer, sap flow and leaf water potential measurements and collected branch-vulnerability curves of six common European tree species. Species-specific Gc reduction was weakly related to the water potentials at which 50% of branch xylem conductivity is lost (P50 ). Instead, we found a stronger relationship with stem rehydration. Species with a stronger Gc control were less effective at refilling stem-water storage as the soil dries, which appeared related to their xylem architecture. Our findings highlight the importance of stem rehydration for water-use regulation in mature trees, which likely relates to the maintenance of adequate stem turgor. We thus conclude that stem rehydration must complement the widely accepted safety-efficiency stomatal control paradigm.
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Affiliation(s)
- Richard L Peters
- Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, B-9000, Ghent, Belgium
- Forest Dynamics, Swiss Federal Research Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, CH-8903, Birmensdorf, Switzerland
- Forest is Life, TERRA Teaching and Research Centre, Gembloux Agro Bio-Tech, University of Liège, Passage des Déportés 2, 5030, Gembloux, Belgium
| | - Kathy Steppe
- Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, B-9000, Ghent, Belgium
| | - Christoforos Pappas
- Department of Civil Engineering, University of Patras, Rio, Patras, 26504, Greece
| | - Roman Zweifel
- Forest Dynamics, Swiss Federal Research Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, CH-8903, Birmensdorf, Switzerland
| | - Flurin Babst
- School of Natural Resources and the Environment, University of Arizona, East Lowell Street 1064, Tucson, AZ, 85721, USA
- Laboratory of Tree-Ring Research, University of Arizona, East Lowell Street 1215, Tucson, AZ, 857121, USA
| | - Lars Dietrich
- Department of Environmental Sciences - Botany, University of Basel, Schönbeinstrasse 6, CH-4056, Basel, Switzerland
| | - Georg von Arx
- Forest Dynamics, Swiss Federal Research Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, CH-8903, Birmensdorf, Switzerland
- Oeschger Centre for Climate Change Research, University of Bern, 3012, Bern, Switzerland
| | - Rafael Poyatos
- CREAF, E08193 Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
- Universitat Autònoma de Barcelona, E08193 Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
| | - Marina Fonti
- Forest Dynamics, Swiss Federal Research Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, CH-8903, Birmensdorf, Switzerland
| | - Patrick Fonti
- Forest Dynamics, Swiss Federal Research Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, CH-8903, Birmensdorf, Switzerland
| | - Charlotte Grossiord
- Plant Ecology Research Laboratory PERL, School for Architecture, Civil and Environmental Engineering, EPFL, CH-1015, Lausanna, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape WSL, CH-1015, Lausanne, Switzerland
| | - Mana Gharun
- Department of Environmental Systems Science, ETH Zurich, Universitatstrasse 2, CH-8092, Zurich, Switzerland
- Department of Geosciences, University of Münster, Heisenbergstrasse 2, 48149, Münster, Germany
| | - Nina Buchmann
- Department of Environmental Systems Science, ETH Zurich, Universitatstrasse 2, CH-8092, Zurich, Switzerland
| | - David N Steger
- Department of Environmental Sciences - Botany, University of Basel, Schönbeinstrasse 6, CH-4056, Basel, Switzerland
| | - Ansgar Kahmen
- Department of Environmental Sciences - Botany, University of Basel, Schönbeinstrasse 6, CH-4056, Basel, Switzerland
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11
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Barkaoui K, Volaire F. Drought survival and recovery in grasses: Stress intensity and plant-plant interactions impact plant dehydration tolerance. PLANT, CELL & ENVIRONMENT 2023; 46:1489-1503. [PMID: 36655754 DOI: 10.1111/pce.14543] [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: 07/22/2022] [Revised: 01/07/2023] [Accepted: 01/16/2023] [Indexed: 06/17/2023]
Abstract
Plant dehydration tolerance confers drought survival in grasses, but the mortality thresholds according to soil water content (SWC), vapour pressure deficit (VPD) and plant-plant interactions are little explored. We compared the dehydration dynamics of leaf meristems, which are the key surviving organs, plant mortality, and recovery of Mediterranean and temperate populations of two perennial grass species, Dactylis glomerata and Festuca arundinacea, grown in monocultures and mixtures under a low-VPD (1.5 kPa) versus a high-VPD drought (2.2 kPa). The lethal drought index (LD50 ), that is, SWC associated with 50% plant mortality, ranged from 2.87% (ψs = -1.68 MPa) to 2.19% (ψs = -4.47 MPa) and reached the lowest values under the low-VPD drought. Populations of D. glomerata were more dehydration-tolerant (lower LD50 ), survived and recovered better than F. arundinacea populations. Plant-plant interactions modified dehydration tolerance and improved post-drought recovery in mixtures compared with monocultures. Water content as low as 20.7%-36.1% in leaf meristems allowed 50% of plants to survive. We conclude that meristem dehydration causes plant mortality and that drought acclimation can increase dehydration tolerance. Genetic diversity, acclimation and plant-plant interactions are essential sources of dehydration tolerance variability to consider when predicting drought-induced mortality.
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Affiliation(s)
- Karim Barkaoui
- CIRAD, UMR ABSys, F-34398 Montpellier, France
- ABSys, Univ Montpellier, CIHEAM-IAMM, CIRAD, INRAE, Institut Agro, Montpellier, France
| | - Florence Volaire
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, INRAE, Montpellier, France
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12
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Potkay A, Feng X. Do stomata optimize turgor-driven growth? A new framework for integrating stomata response with whole-plant hydraulics and carbon balance. THE NEW PHYTOLOGIST 2023; 238:506-528. [PMID: 36377138 DOI: 10.1111/nph.18620] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 11/11/2022] [Indexed: 06/16/2023]
Abstract
Every existing optimal stomatal model uses photosynthetic carbon assimilation as a proxy for plant evolutionary fitness. However, assimilation and growth are often decoupled, making assimilation less ideal for representing fitness when optimizing stomatal conductance to water vapor and carbon dioxide. Instead, growth should be considered a closer proxy for fitness. We hypothesize stomata have evolved to maximize turgor-driven growth, instead of assimilation, over entire plants' lifetimes, improving their abilities to compete and reproduce. We develop a stomata model that dynamically maximizes whole-stem growth following principles from turgor-driven growth models. Stomata open to assimilate carbohydrates that supply growth and osmotically generate turgor, while stomata close to prevent losses of turgor and growth due to negative water potentials. In steady state, the growth optimization model captures realistic stomatal, growth, and carbohydrate responses to environmental cues, reconciles conflicting interpretations within existing stomatal optimization theories, and explains patterns of carbohydrate storage and xylem conductance observed during and after drought. Our growth optimization hypothesis introduces a new paradigm for stomatal optimization models, elevates the role of whole-plant carbon use and carbon storage in stomatal functioning, and has the potential to simultaneously predict gross productivity, net productivity, and plant mortality through a single, consistent modeling framework.
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Affiliation(s)
- Aaron Potkay
- Department of Civil, Environmental, and Geo-Engineering, University of Minnesota, Twin Cities, Minneapolis, MN, 55455, USA
- Saint Anthony Falls Laboratory, University of Minnesota, Twin Cities, Minneapolis, MN, 55455, USA
| | - Xue Feng
- Department of Civil, Environmental, and Geo-Engineering, University of Minnesota, Twin Cities, Minneapolis, MN, 55455, USA
- Saint Anthony Falls Laboratory, University of Minnesota, Twin Cities, Minneapolis, MN, 55455, USA
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13
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Barotto AJ, Martínez-Meier A, Segura V, Monteoliva S, Charpentier JP, Gyenge J, Sergent AS, Millier F, Rozenberg P, Fernández ME. Use of near-infrared spectroscopy to estimate physical, anatomical and hydraulic properties of Eucalyptus wood. TREE PHYSIOLOGY 2023; 43:501-514. [PMID: 36383394 DOI: 10.1093/treephys/tpac132] [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: 05/12/2022] [Revised: 09/26/2022] [Accepted: 11/11/2022] [Indexed: 05/03/2023]
Abstract
Tree breeding programs and wood industries require simple, time- and cost-effective techniques to process large volumes of samples. In recent decades, near-infrared spectroscopy (NIRS) has been acknowledged as one of the most powerful techniques for wood analysis, making it the most used tool for high-throughput phenotyping. Previous studies have shown that a significant number of anatomical, physical, chemical and mechanical wood properties can be estimated through NIRS, both for angiosperm and gymnosperm species. However, the ability of this technique to predict functional traits related to drought resistance has been poorly explored, especially in angiosperm species. This is particularly relevant since determining xylem hydraulic properties by conventional techniques is complex and time-consuming, clearly limiting its use in studies and applications that demand large amounts of samples. In this study, we measured several wood anatomical and hydraulic traits and collected NIR spectra in branches of two Eucalyptus L'Hér species. We developed NIRS calibration models and discussed their ability to accurately predict the studied traits. The models generated allowed us to adequately calibrate the reference traits, with high R2 (≥0.75) for traits such as P12, P88, the slope of the vulnerability curves to xylem embolism or the fiber wall fraction, and with lower R2 (0.39-0.52) for P50, maximum hydraulic conductivity or frequency of ray parenchyma. We found that certain wavenumbers improve models' calibration, with those in the range of 4000-5500 cm-1 predicting the highest number of both anatomical and functional traits. We concluded that the use of NIRS allows calibrating models with potential predictive value not only for wood structural and chemical variables but also for anatomical and functional traits related to drought resistance in wood types with complex structure as eucalypts. These results are promising in light of the required knowledge about species and genotypes adaptability to global climatic change.
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Affiliation(s)
- Antonio José Barotto
- Cátedra de Dendrología, Facultad de Ciencias Agrarias y Forestales, Universidad Nacional de La Plata, CC 31 (1900) La Plata, Argentina
| | - Alejandro Martínez-Meier
- INTA EEA Bariloche, Grupo de Ecología Forestal, UEDD IFAB INTA-CONICET - Laboratorio de Ecología, Ecofisiología y Madera (LEEMA), Modesta Victoria 4450 (8400), Río Negro, Argentina
- Laboratorio Internacional Asociado LIA-Forestia (INTA - INRAE - UNAH)
| | - Vincent Segura
- UMR AGAP Institut, Univ Montpellier, CIRAD, INRAE, Institut Agro, F-34398 Montpellier, France
| | | | - Jean-Paul Charpentier
- UMR 0588 BioForA, INRAE, ONF, Orléans, France, 2163 Avenue de la Pomme de Pin, CS 40001 Ardon, 45075 Orléans Cedex 2, France
| | - Javier Gyenge
- Laboratorio Internacional Asociado LIA-Forestia (INTA - INRAE - UNAH)
- Grupo Forestal, UEDD IPADS INTA-CONICET-Oficina Tandil, Rodríguez 370 (7000), Tandil, Argentina
| | - Anne Sophie Sergent
- Laboratorio Internacional Asociado LIA-Forestia (INTA - INRAE - UNAH)
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina UEDD IFAB INTA-CONICET - Laboratorio de Ecología, Ecofisiología y Madera (LEEMA), Modesta Victoria 4450 (8400), RíoNegro, Argentina
| | - Frédéric Millier
- UMR 0588 BioForA, INRAE, ONF, Orléans, France, 2163 Avenue de la Pomme de Pin, CS 40001 Ardon, 45075 Orléans Cedex 2, France
| | - Philippe Rozenberg
- Laboratorio Internacional Asociado LIA-Forestia (INTA - INRAE - UNAH)
- UMR 0588 BioForA, INRAE, ONF, Orléans, France, 2163 Avenue de la Pomme de Pin, CS 40001 Ardon, 45075 Orléans Cedex 2, France
| | - María Elena Fernández
- Laboratorio Internacional Asociado LIA-Forestia (INTA - INRAE - UNAH)
- Grupo Forestal, UEDD IPADS INTA-CONICET-Oficina Tandil, Rodríguez 370 (7000), Tandil, Argentina
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14
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Volaire F, Barkaoui K, Grémillet D, Charrier G, Dangles O, Lamarque LJ, Martin-StPaul N, Chuine I. Is a seasonally reduced growth potential a convergent strategy to survive drought and frost in plants? ANNALS OF BOTANY 2023; 131:245-254. [PMID: 36567631 PMCID: PMC9992932 DOI: 10.1093/aob/mcac153] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 12/14/2022] [Indexed: 06/17/2023]
Abstract
BACKGROUND Plants have adapted to survive seasonal life-threatening frost and drought. However, the timing and frequency of such events are impacted by climate change, jeopardizing plant survival. Understanding better the strategies of survival to dehydration stress is therefore timely and can be enhanced by the cross-fertilization of research between disciplines (ecology, physiology), models (woody, herbaceous species) and types of stress (drought, frost). SCOPE We build upon the 'growth-stress survival' trade-off, which underpins the identification of global plant strategies across environments along a 'fast-slow' economics spectrum. Although phenological adaptations such as dormancy are crucial to survive stress, plant global strategies along the fast-slow economic spectrum rarely integrate growth variations across seasons. We argue that the growth-stress survival trade-off can be a useful framework to identify convergent plant ecophysiological strategies to survive both frost and drought. We review evidence that reduced physiological activity, embolism resistance and dehydration tolerance of meristematic tissues are interdependent strategies that determine thresholds of mortality among plants under severe frost and drought. We show that complete dormancy, i.e. programmed growth cessation, before stress occurrence, minimizes water flows and maximizes dehydration tolerance during seasonal life-threatening stresses. We propose that incomplete dormancy, i.e. the programmed reduction of growth potential during the harshest seasons, could be an overlooked but major adaptation across plants. Quantifying stress survival in a range of non-dormant versus winter- or summer-dormant plants, should reveal to what extent incomplete to complete dormancy could represent a proxy for dehydration tolerance and stress survival. CONCLUSIONS Our review of the strategies involved in dehydration stress survival suggests that winter and summer dormancy are insufficiently acknowledged as plant ecological strategies. Incorporating a seasonal fast-slow economics spectrum into global plant strategies improves our understanding of plant resilience to seasonal stress and refines our prevision of plant adaptation to extreme climatic events.
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Affiliation(s)
- Florence Volaire
- CEFE, Université Montpellier, INRAE, CNRS, EPHE, IRD, F-34090 Montpellier, France
| | - Karim Barkaoui
- CIRAD, UMR ABSys, F-34398 Montpellier, France
- ABSys, Université F-34060 Montpellier, CIHEAM-IAMM, CIRAD, INRAE, Institut Agro, Montpellier, France
| | - David Grémillet
- CEFE, Université Montpellier, CNRS, EPHE, IRD, F-34090 Montpellier, France
- Percy FitzPatrick Institute of African Ornithology, University of Cape Town, Rondebosch, South Africa
| | - Guillaume Charrier
- Université Clermont Auvergne, INRAE, PIAF, F-63000 Clermont Ferrand, France
| | - Olivier Dangles
- CEFE, Université Montpellier, CNRS, EPHE, IRD, F-34090 Montpellier, France
| | - Laurent J Lamarque
- Département des Sciences de l’Environnement, Université du Québec à Trois-Rivières, Trois-Rivières, QC, G9A 5H7, Canada
| | - Nicolas Martin-StPaul
- INRAE, URFM, Domaine Saint Paul, Centre de recherche PACA, 228 route de l’Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, France
| | - Isabelle Chuine
- CEFE, Université Montpellier, CNRS, EPHE, IRD, F-34090 Montpellier, France
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15
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Responses to Drought Stress in Poplar: What Do We Know and What Can We Learn? Life (Basel) 2023; 13:life13020533. [PMID: 36836891 PMCID: PMC9962866 DOI: 10.3390/life13020533] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 02/09/2023] [Accepted: 02/11/2023] [Indexed: 02/17/2023] Open
Abstract
Poplar (Populus spp.) is a high-value crop for wood and biomass production and a model organism for tree physiology and genomics. The early release, in 2006, of the complete genome sequence of P. trichocarpa was followed by a wealth of studies that significantly enriched our knowledge of complex pathways inherent to woody plants, such as lignin biosynthesis and secondary cell wall deposition. Recently, in the attempt to cope with the challenges posed by ongoing climate change, fundamental studies and breeding programs with poplar have gradually shifted their focus to address the responses to abiotic stresses, particularly drought. Taking advantage from a set of modern genomic and phenotyping tools, these studies are now shedding light on important processes, including embolism formation (the entry and expansion of air bubbles in the xylem) and repair, the impact of drought stress on biomass yield and quality, and the long-term effects of drought events. In this review, we summarize the status of the research on the molecular bases of the responses to drought in poplar. We highlight how this knowledge can be exploited to select more tolerant genotypes and how it can be translated to other tree species to improve our understanding of forest dynamics under rapidly changing environmental conditions.
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16
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Mantova M, Cochard H, Burlett R, Delzon S, King A, Rodriguez-Dominguez CM, Ahmed MA, Trueba S, Torres-Ruiz JM. On the path from xylem hydraulic failure to downstream cell death. THE NEW PHYTOLOGIST 2023; 237:793-806. [PMID: 36305207 DOI: 10.1111/nph.18578] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 10/17/2022] [Indexed: 06/16/2023]
Abstract
Xylem hydraulic failure (HF) has been identified as a ubiquitous factor in triggering drought-induced tree mortality through the damage induced by the progressive dehydration of plant living cells. However, fundamental evidence of the mechanistic link connecting xylem HF to cell death has not been identified yet. The main aim of this study was to evaluate, at the leaf level, the relationship between loss of hydraulic function due to cavitation and cell death under drought conditions and discern how this relationship varied across species with contrasting resistances to cavitation. Drought was induced by withholding water from potted seedlings, and their leaves were sampled to measure their relative water content (RWC) and cell mortality. Vulnerability curves to cavitation at the leaf level were constructed for each species. An increment in cavitation events occurrence precedes the onset of cell mortality. A variation in cells tolerance to dehydration was observed along with the resistance to cavitation. Overall, our results indicate that the onset of cellular mortality occurs at lower RWC than the one for cavitation indicating the role of cavitation in triggering cellular death. They also evidenced a critical RWC for cellular death varying across species with different cavitation resistance.
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Affiliation(s)
- Marylou Mantova
- Université Clermont Auvergne, INRAE, PIAF, 63000, Clermont-Ferrand, France
| | - Hervé Cochard
- Université Clermont Auvergne, INRAE, PIAF, 63000, Clermont-Ferrand, France
| | - Régis Burlett
- Université Bordeaux, INRAE, BIOGECO, 33615, Pessac, France
| | - Sylvain Delzon
- Université Bordeaux, INRAE, BIOGECO, 33615, Pessac, France
| | - Andrew King
- Synchrotron SOLEIL, L'Orme des Merisiers, 91190, Gif-sur-Yvette cedex, France
| | - Celia M Rodriguez-Dominguez
- Irrigation and Crop Ecophysiology Group, Instituto de Recursos Naturales y Agrobiologia de Sevilla (IRNAS, CSIC), Avenida Reina Mercedes, 10, 41012, Sevilla, Spain
| | - Mutez A Ahmed
- Chair of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, 95440, Bayreuth, Germany
- Department of Land, Air and Water Resources, University of California Davis, Davis, CA, 95616, USA
| | | | - José M Torres-Ruiz
- Université Clermont Auvergne, INRAE, PIAF, 63000, Clermont-Ferrand, France
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17
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Trifilò P, Abate E, Petruzzellis F, Azzarà M, Nardini A. Critical water contents at leaf, stem and root level leading to irreversible drought-induced damage in two woody and one herbaceous species. PLANT, CELL & ENVIRONMENT 2023; 46:119-132. [PMID: 36266962 DOI: 10.1111/pce.14469] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 10/11/2022] [Accepted: 10/16/2022] [Indexed: 06/16/2023]
Abstract
Plant water content is a simple and promising parameter for monitoring drought-driven plant mortality risk. However, critical water content thresholds leading to cell damage and plant failure are still unknown. Moreover, it is unclear whether whole-plant or a specific organ water content is the most reliable indicator of mortality risk. We assessed differences in dehydration thresholds in leaf, stem and root samples, hampering the organ-specific rehydration capacity and increasing the mortality risk. We also tested eventual differences between a fast experimental dehydration of uprooted plants, compared to long-term water stress induced by withholding irrigation in potted plants. We investigated three species with different growth forms and leaf habits i.e., Helianthus annuus (herbaceous), Populus nigra (deciduous tree) and Quercus ilex (evergreen tree). Results obtained by the two dehydration treatments largely overlapped, thus validating bench dehydration as a fast but reliable method to assess species-specific critical water content thresholds. Regardless of the organ considered, a relative water content value of 60% induced significant cell membrane damage and loss of rehydration capacity, thus leading to irreversible plant failure and death.
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Affiliation(s)
- Patrizia Trifilò
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università di Messina, Messina, Italy
| | - Elisa Abate
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università di Messina, Messina, Italy
| | | | - Maria Azzarà
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università di Messina, Messina, Italy
| | - Andrea Nardini
- Dipartimento di Scienze della Vita, Università di Trieste, Trieste, Italy
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18
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Petruzzellis F, Tordoni E, Di Bonaventura A, Tomasella M, Natale S, Panepinto F, Bacaro G, Nardini A. Turgor loss point and vulnerability to xylem embolism predict species-specific risk of drought-induced decline of urban trees. PLANT BIOLOGY (STUTTGART, GERMANY) 2022; 24:1198-1207. [PMID: 34704333 PMCID: PMC10078640 DOI: 10.1111/plb.13355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 09/27/2021] [Indexed: 06/13/2023]
Abstract
Increasing frequency and severity of drought events is posing risks to trees' health, including those planted in urban settlements. Drought-induced decline of urban trees negatively affects ecosystem services of urban green spaces and implies cost for maintenance and removal of plants. We aimed at identifying physiological traits that can explain and predict the species-specific vulnerability to climate change in urban habitats. We assessed the relationships between long-term risk of decline of different tree species in a medium-sized town and their key indicators of drought stress tolerance, i.e. turgor loss point (TLP) and vulnerability to xylem embolism (P50 ). Starting from 2012, the study area experienced several summer seasons with positive anomalies of temperature and negative anomalies of precipitation. This trend was coupled with increasing percentages of urban trees showing signs of crown die-back and mortality. The species-specific risk of decline was higher for species with less negative TLP and P50 values. The relationship between species-specific risk of climate change-induced decline of urban trees and key physiological indicators of drought tolerance confirms findings obtained in natural forests and highlights that TLP and P50 are useful indicators for species selection for tree plantation in towns, to mitigate negative impacts of climate change.
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Affiliation(s)
- F. Petruzzellis
- Dipartimento di Scienze della VitaUniversità di TriesteTriesteItalia
- Dipartimento di Scienze agroalimentari, ambientali e animaliUniversità di UdineUdineItalia
| | - E. Tordoni
- Dipartimento di Scienze della VitaUniversità di TriesteTriesteItalia
- Institute of Ecology and Earth ScienceUniversity of TartuTartuEstonia
| | - A. Di Bonaventura
- Dipartimento di Scienze della VitaUniversità di TriesteTriesteItalia
| | - M. Tomasella
- Dipartimento di Scienze della VitaUniversità di TriesteTriesteItalia
| | - S. Natale
- Dipartimento di Scienze della VitaUniversità di TriesteTriesteItalia
| | - F. Panepinto
- Unità Tecnica Alberature e ParchiServizio Strade e Verde PubblicoComune di TriesteTriesteItalia
| | - G. Bacaro
- Dipartimento di Scienze della VitaUniversità di TriesteTriesteItalia
| | - A. Nardini
- Dipartimento di Scienze della VitaUniversità di TriesteTriesteItalia
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19
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Knüver T, Bär A, Ganthaler A, Gebhardt T, Grams TEE, Häberle K, Hesse BD, Losso A, Tomedi I, Mayr S, Beikircher B. Recovery after long-term summer drought: Hydraulic measurements reveal legacy effects in trunks of Picea abies but not in Fagus sylvatica. PLANT BIOLOGY (STUTTGART, GERMANY) 2022; 24:1240-1253. [PMID: 35611757 PMCID: PMC10084041 DOI: 10.1111/plb.13444] [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: 10/29/2021] [Accepted: 05/09/2022] [Indexed: 06/15/2023]
Abstract
Climate change is expected to increase the frequency and intensity of summer droughts. Sufficient drought resistance, the ability to acclimate to and/or recover after drought, is thus crucial for forest tree species. However, studies on the hydraulics of mature trees during and after drought in natura are scarce. In this study, we analysed trunk water content (electrical resistivity: ER) and further hydraulic (water potential, sap flow density, specific hydraulic conductivity, vulnerability to embolism) as well as wood anatomical traits (tree ring width, conduit diameter, conduit wall reinforcement) of drought-stressed (artificially induced summer drought via throughfall-exclusion) and unstressed Picea abies and Fagus sylvatica trees. In P. abies, ER indicated a strong reduction in trunk water content after 5 years of summer drought, corresponding to significantly lower pre-dawn leaf water potential and xylem sap flow density. Vulnerability to embolism tended to be higher in drought-stressed trees. In F. sylvatica, only small differences between drought-stressed and control trees were observed. Re-watering led to a rapid increase in water potentials and xylem sap flow of both drought-stressed trees, and to increased growth rates in the next growing season. ER analyses revealed lower trunk water content in P. abies trees growing on throughfall-exclusion plots even 1 year after re-watering, indicating a limited capacity to restore internal water reserves. Results demonstrated that P. abies is more susceptible to recurrent summer drought than F. sylvatica, and can exhibit long-lasting and pronounced legacy effects in trunk water reserves.
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Affiliation(s)
- T. Knüver
- Department of BotanyUniversity of InnsbruckInnsbruckAustria
| | - A. Bär
- Department of BotanyUniversity of InnsbruckInnsbruckAustria
| | - A. Ganthaler
- Department of BotanyUniversity of InnsbruckInnsbruckAustria
| | - T. Gebhardt
- Technical University of MunichSchool of Life SciencesProfessorship for Land Surface‐Atmosphere Interactions AG Ecophysiology of PlantsFreisingGermany
| | - T. E. E. Grams
- Technical University of MunichSchool of Life SciencesProfessorship for Land Surface‐Atmosphere Interactions AG Ecophysiology of PlantsFreisingGermany
| | - K.‐H. Häberle
- Technical University of MunichSchool of Life SciencesChair of Restoration EcologyFreisingGermany
| | - B. D. Hesse
- Technical University of MunichSchool of Life SciencesProfessorship for Land Surface‐Atmosphere Interactions AG Ecophysiology of PlantsFreisingGermany
| | - A. Losso
- Department of BotanyUniversity of InnsbruckInnsbruckAustria
- Hawkesbury Institute for the EnvironmentWestern Sydney UniversityRichmondAustralia
| | - I. Tomedi
- Department of BotanyUniversity of InnsbruckInnsbruckAustria
| | - S. Mayr
- Department of BotanyUniversity of InnsbruckInnsbruckAustria
| | - B. Beikircher
- Department of BotanyUniversity of InnsbruckInnsbruckAustria
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20
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Oliveira LA, Cardoso AA, Andrade MT, Pereira TS, Araújo WL, Santos GA, Damatta FM, Martins SCV. Exploring leaf hydraulic traits to predict drought tolerance of Eucalyptus clones. TREE PHYSIOLOGY 2022; 42:1750-1761. [PMID: 35388901 DOI: 10.1093/treephys/tpac040] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 04/04/2022] [Indexed: 06/14/2023]
Abstract
Ongoing changes in climate, and the consequent mortality of natural and cultivated forests across the globe, highlight the urgent need to understand the plant traits associated with greater tolerance to drought. Here, we aimed at assessing key foliar traits, with a focus on the hydraulic component, that could confer a differential ability to tolerate drought in three commercial hybrids of the most important Eucalyptus species utilized in tropical silviculture: E. urophyla, E. grandis and E. camaldulensis. All genotypes exhibited similar water potential when the 90% stomatal closure (Ψgs90) occurs with Ψgs90 always preceding the start of embolism events. The drought-tolerant hybrid showed a higher leaf resistance to embolism, but the leaf hydraulic efficiency was similar among all genotypes. Other traits presented by the drought-tolerant hybrid were a higher cell wall reinforcement, lower value of osmotic potential at full turgor and greater bulk modulus of elasticity. We also identified that the leaf capacitance after the turgor loss, the ratio between cell wall thickness (t) and lumen breadth (b) ratio (t/b)3, and the minimal conductance might be good proxies for screening drought-tolerant Eucalyptus genotypes. Our findings suggest that xylem resistance to embolism can be an important component of drought tolerance in Eucalyptus in addition to other traits aimed at delaying the development of high tensions in the xylem. Highlight Drought tolerance in tropical Eucalyptus hybrids encompasses a high leaf resistance to embolism and a suite of traits aimed at delaying the development of high tensions in the xylem.
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Affiliation(s)
- Leonardo A Oliveira
- Departmento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Amanda A Cardoso
- Departmento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695, USA
| | - Moab T Andrade
- Departmento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Talitha S Pereira
- Departmento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Wagner L Araújo
- Departmento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Gleison A Santos
- Departmento de Engenharia Florestal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Fábio M Damatta
- Departmento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Samuel C V Martins
- Departmento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
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21
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Morcillo L, Muñoz-Rengifo JC, Torres-Ruiz JM, Delzon S, Moutahir H, Vilagrosa A. Post-drought conditions and hydraulic dysfunction determine tree resilience and mortality across Mediterranean Aleppo pine (Pinus halepensis) populations after an extreme drought event. TREE PHYSIOLOGY 2022; 42:1364-1376. [PMID: 35038335 DOI: 10.1093/treephys/tpac001] [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: 01/12/2021] [Accepted: 01/11/2022] [Indexed: 06/14/2023]
Abstract
Drought-related tree mortality is a global phenomenon that currently affects a wide range of forests. Key functional variables on plant hydraulics, carbon economy, growth and allocation have been identified and play a role in tree drought responses. However, tree mortality thresholds based on such variables are difficult to identify, especially under field conditions. We studied several Aleppo pine populations differently affected by an extreme drought event in 2014, with mortality rates ranging from no mortality to 90% in the most severely affected population. We hypothesized that mortality is linked with high levels of xylem embolism, i.e., hydraulic dysfunction, which would also lead to lower tree resistance to drought in subsequent years. Despite not finding any differences among populations in the vulnerability curves to xylem embolism, there were large differences in the hydraulic safety margin (HSM) and the hydraulic dysfunction level. High mortality rates were associated with a negative HSM when xylem embolism reached values over 60%. We also found forest weakening and post-drought mortality related to a low hydraulic water transport capacity, reduced plant growth, low carbohydrate contents and high pest infestation rates. Our results highlight the importance of drought severity and the hydraulic dysfunction level on pine mortality, as well as post-drought conditions during recovery processes.
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Affiliation(s)
- L Morcillo
- Mediterranean Center for Environmental Studies (CEAM Foundation), Joint Research Unit University of Alicante-CEAM, University of Alicante, Alicante 03690, Spain
| | - J C Muñoz-Rengifo
- Department of Ecology, University of Alicante, Alicante 03690, Spain
- Department of Earth Science, Universidad Estatal Amazónica, Pastaza 160150, Ecuador
| | - J M Torres-Ruiz
- Université Clermont-Auvergne, INRAE, PIAF, Clermont-Ferrand 63000, France
| | - S Delzon
- Université Bordeaux, INRAE, BIOGECO, Pessac 33615, France
| | - H Moutahir
- Mediterranean Center for Environmental Studies (CEAM Foundation), Joint Research Unit University of Alicante-CEAM, University of Alicante, Alicante 03690, Spain
| | - A Vilagrosa
- Mediterranean Center for Environmental Studies (CEAM Foundation), Joint Research Unit University of Alicante-CEAM, University of Alicante, Alicante 03690, Spain
- Department of Ecology, University of Alicante, Alicante 03690, Spain
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22
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Li S, Li X, Wang J, Chen Z, Lu S, Wan X, Sun H, Wang L, Delzon S, Cochard H, Jiang X, Shu J, Zheng J, Yin Y. Hydraulic traits are coupled with plant anatomical traits under drought-rewatering cycles in Ginkgo biloba L. TREE PHYSIOLOGY 2022; 42:1216-1227. [PMID: 34962276 DOI: 10.1093/treephys/tpab174] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 12/22/2021] [Indexed: 06/14/2023]
Abstract
Investigating the responses of plant anatomical traits of trees to drought-rewatering cycles helps us to understand their responses to climate change; however, such work has not been adequately reported. In this study, Ginkgo biloba L. saplings were subjected to moderate, severe, extreme and lethal drought conditions by withholding water according to the percentage loss of hydraulic conductivity (PLC) and rewatering on a regular basis. Samples of phloem, cambium and xylem were collected to quantify their cellular properties including cambium and phloem cell vitality, xylem growth ring width, pit aspiration rates and pit membrane thickness using light microscopy and transmission microscopy. The results showed that the mortality rate of G. biloba saplings reached 90% at approximately P88 (xylem water potential inducing 88% loss of hydraulic conductivity). The onset of cambium and phloem cell mortality might be in accordance with that of xylem embolism. Close negative correlations between xylem water potential and PLC and between xylem water potential and cambium and phloem mortality suggested that xylem hydraulic traits are coupled with anatomical traits under declining xylem water potential. Cambium and phloem cell vitality as well as xylem growth ring width decreased significantly with increasing drought conditions. However, xylem pit membrane thickness, cambial zone width and cambial cell geometry were not affected by the drought-rewatering cycles. The tracheid radial diameter, intertracheid cell wall thickness and tracheid density decreased significantly during both drought conditions and rewatering conditions. In addition to hydraulic traits, cambium and phloem cell vitality can be used as anatomical traits to evaluate the mortality of G. biloba under drought. Future work is proposed to observe the dynamics of pit aspiration rates under drought-rewatering cycles in situ to deepen our understanding of the essential role of bordered pits in the 'air-seeding' mechanism.
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Affiliation(s)
- Shan Li
- Department of Wood Anatomy and Utilization, Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, P.R. China
- Wood Collections (WOODPEDIA), Chinese Academy of Forestry, Beijing 100091, P.R. China
- Department of Environmental Science and Ecology, School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an 710021, P.R. China
| | - Xin Li
- College of Forestry, Beijing Forestry University, Beijing 100083, P.R. China
| | - Jie Wang
- Department of Wood Anatomy and Utilization, Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, P.R. China
- Wood Collections (WOODPEDIA), Chinese Academy of Forestry, Beijing 100091, P.R. China
| | - Zhicheng Chen
- Key laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, P.R. China
| | - Sen Lu
- Department of Environmental Science and Ecology, School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an 710021, P.R. China
| | - Xianchong Wan
- Key laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, P.R. China
| | - Hongyan Sun
- Beijing Institute of Landscape Architecture, Beijing 100102, P.R. China
- Beijing Key Lab of Greening Plants Breeding, Beijing Institute of Landscape Architecture, Beijing 100102, P.R. China
| | - Li Wang
- Center for Biological Imaging, Institute of Biophysics, Chinese Academy of Science, Beijing 100101, P.R. China
| | - Sylvain Delzon
- INRAE, BIOGECO, University of Bordeaux, 33615 Pessac, France
| | - Herve Cochard
- INRAE, PIAF, Université Clermont Auvergne, 63000 Clermont-Ferrand, France
| | - Xiaomei Jiang
- Department of Wood Anatomy and Utilization, Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, P.R. China
- Wood Collections (WOODPEDIA), Chinese Academy of Forestry, Beijing 100091, P.R. China
| | - Jianhua Shu
- Beijing Institute of Landscape Architecture, Beijing 100102, P.R. China
- Beijing Key Lab of Greening Plants Breeding, Beijing Institute of Landscape Architecture, Beijing 100102, P.R. China
| | - Jingming Zheng
- College of Forestry, Beijing Forestry University, Beijing 100083, P.R. China
| | - Yafang Yin
- Department of Wood Anatomy and Utilization, Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, P.R. China
- Wood Collections (WOODPEDIA), Chinese Academy of Forestry, Beijing 100091, P.R. China
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23
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Hajek P, Link RM, Nock CA, Bauhus J, Gebauer T, Gessler A, Kovach K, Messier C, Paquette A, Saurer M, Scherer-Lorenzen M, Rose L, Schuldt B. Mutually inclusive mechanisms of drought-induced tree mortality. GLOBAL CHANGE BIOLOGY 2022; 28:3365-3378. [PMID: 35246895 DOI: 10.1111/gcb.16146] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 12/16/2021] [Indexed: 06/14/2023]
Abstract
Unprecedented tree dieback across Central Europe caused by recent global change-type drought events highlights the need for a better mechanistic understanding of drought-induced tree mortality. Although numerous physiological risk factors have been identified, the importance of two principal mechanisms, hydraulic failure and carbon starvation, is still debated. It further remains largely unresolved how the local neighborhood composition affects individual mortality risk. We studied 9435 young trees of 12 temperate species planted in a diversity experiment in 2013 to assess how hydraulic traits, carbon dynamics, pest infestation, tree height and neighborhood competition influence individual mortality risk. Following the most extreme global change-type drought since record in 2018, one third of these trees died. Across species, hydraulic safety margins (HSMs) were negatively and a shift towards a higher sugar fraction in the non-structural carbohydrate (NSC) pool positively associated with mortality risk. Moreover, trees infested by bark beetles had a higher mortality risk, and taller trees a lower mortality risk. Most neighborhood interactions were beneficial, although neighborhood effects were highly species-specific. Species that suffered more from drought, especially Larix spp. and Betula spp., tended to increase the survival probability of their neighbors and vice versa. While severe tissue dehydration marks the final stage of drought-induced tree mortality, we show that hydraulic failure is interrelated with a series of other, mutually inclusive processes. These include shifts in NSC pools driven by osmotic adjustment and/or starch depletion as well as pest infestation and are modulated by the size and species identity of a tree and its neighbors. A more holistic view that accounts for multiple causes of drought-induced tree mortality is required to improve predictions of trends in global forest dynamics and to identify mutually beneficial species combinations.
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Affiliation(s)
- Peter Hajek
- Geobotany, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Roman M Link
- Chair of Ecophysiology and Vegetation Ecology, University of Würzburg, Julius-von-Sachs-Institute of Biological Sciences, Würzburg, Germany
| | - Charles A Nock
- Geobotany, Faculty of Biology, University of Freiburg, Freiburg, Germany
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada
| | - Jürgen Bauhus
- Chair of Silviculture, University of Freiburg, Freiburg, Germany
| | - Tobias Gebauer
- Geobotany, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Arthur Gessler
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf, Switzerland
- ETH Zurich, Institute of Terrestrial Ecosystems, Zurich, Switzerland
| | - Kyle Kovach
- Geobotany, Faculty of Biology, University of Freiburg, Freiburg, Germany
- Department of Forest and Wildlife Ecology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Christian Messier
- Center for Forest Research, Université du Québec à Montréal, Montréal, Quebec, Canada
- University of Quebec in Outaouais (UQO), Institut des Sciences de la Forêt Tempérée (ISFORT), Gatineau, Quebec, Canada
| | - Alain Paquette
- Center for Forest Research, Université du Québec à Montréal, Montréal, Quebec, Canada
| | - Matthias Saurer
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf, Switzerland
| | | | - Laura Rose
- Geobotany, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Bernhard Schuldt
- Chair of Ecophysiology and Vegetation Ecology, University of Würzburg, Julius-von-Sachs-Institute of Biological Sciences, Würzburg, Germany
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24
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Klein T, Torres-Ruiz JM, Albers JJ. Conifer desiccation in the 2021 NW heatwave confirms the role of hydraulic damage. TREE PHYSIOLOGY 2022; 42:722-726. [PMID: 35084498 DOI: 10.1093/treephys/tpac007] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 01/25/2022] [Indexed: 06/14/2023]
Abstract
The unprecedented heatwave which hit the Pacific northwest of North America in late June-early July 2021 impacted ecosystems and communities, yet evidence for and analysis of this impact are still missing. Here we bring a unique dataset quantifying the impact on conifer trees, which are keystone species of many northwest ecosystems. Moreover, we take advantage of this exceptional event as a broad, extreme, 'field experiment' to test a fundamental theory in plant physiology and prepare our forests for a harsher future. Overall, the data collected confirm the role of hydraulic vulnerability in drought-induced injury to trees.
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Affiliation(s)
- Tamir Klein
- Department of Plant & Environmental Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Jose M Torres-Ruiz
- Université Clermont-Auvergne, INRAE, PIAF, Clermont-Ferrand 63000, France
| | - John J Albers
- Albers Marcovina Vista Gardens, Bremerton, WA 98310-2150, USA
- Department of Medicine, University of Washington, Seattle, WA 98195, USA
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25
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Mantova M, Herbette S, Cochard H, Torres-Ruiz JM. Hydraulic failure and tree mortality: from correlation to causation. TRENDS IN PLANT SCIENCE 2022; 27:335-345. [PMID: 34772610 DOI: 10.1016/j.tplants.2021.10.003] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 09/27/2021] [Accepted: 10/15/2021] [Indexed: 06/13/2023]
Abstract
Xylem hydraulic failure has been recognized as a pervasive factor in the triggering of drought-induced tree mortality. However, foundational evidence of the mechanistic link connecting hydraulic failure with living cell damage and tree death has not been identified yet, compromising our ability to predict mortality events. Meristematic cells are involved in the recovery of trees from drought, and focusing on their vitality and functionality after a drought event could provide novel information on the mechanistic link between hydraulic failure and drought-induced tree mortality. In this Opinion, we focus on the cell's critical hydration status for tree recovery from drought and how it links with the membrane integrity of the meristems.
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Affiliation(s)
- Marylou Mantova
- Université Clermont Auvergne, INRAE, PIAF, 63000 Clermont-Ferrand, France
| | - Stéphane Herbette
- Université Clermont Auvergne, INRAE, PIAF, 63000 Clermont-Ferrand, France
| | - Hervé Cochard
- Université Clermont Auvergne, INRAE, PIAF, 63000 Clermont-Ferrand, France
| | - José M Torres-Ruiz
- Université Clermont Auvergne, INRAE, PIAF, 63000 Clermont-Ferrand, France.
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26
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Duan H, Resco de Dios V, Wang D, Zhao N, Huang G, Liu W, Wu J, Zhou S, Choat B, Tissue DT. Testing the limits of plant drought stress and subsequent recovery in four provenances of a widely distributed subtropical tree species. PLANT, CELL & ENVIRONMENT 2022; 45:1187-1203. [PMID: 34985807 DOI: 10.1111/pce.14254] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Revised: 12/05/2021] [Accepted: 12/06/2021] [Indexed: 06/14/2023]
Abstract
Drought-induced tree mortality may increase with ongoing climate change. Unraveling the links between stem hydraulics and mortality thresholds, and the effects of intraspecific variation, remain important unresolved issues. We conducted a water manipulation experiment in a rain-out shelter, using four provenances of Schima superba originating from a gradient of annual precipitation (1124-1796 mm) and temperature (16.4-22.4°C). Seedlings were droughted to three levels of percentage loss of hydraulic conductivity (i.e., P50 , P88 and P99) and subsequently rewatered to field capacity for 30 days; traits related to water and carbon relations were measured. The lethal water potential associated with incipient mortality was between P50 and P88 . Seedlings exhibited similar drought responses in xylem water potential, hydraulic conductivity and gas exchange. Upon rehydration, patterns of gas exchange differed among provenances but were not related to the climate at the origin. The four provenances exhibited a similar degree of stem hydraulic recovery, which was correlated with the magnitude of antecedent drought and stem soluble sugar at the end of the drought. Results suggest that there were intraspecific differences in the capacity of S. superba seedlings for carbon assimilation during recovery, indicating a decoupling between gas exchange recovery and stem hydraulics across provenances.
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Affiliation(s)
- Honglang Duan
- Institute for Forest Resources and Environment of Guizhou, Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou Province, College of Forestry, Guizhou University, Guiyang, China
- Jiangxi Provincial Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology, Nanchang Institute of Technology, Nanchang, China
| | - Víctor Resco de Dios
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, China
- Department of Crop and Forest Sciences, Unversitat de Lleida, Lleida, Spain
- Joint Research Unit CTFC-AGROTECNIO-CERCA Centre, Lleida, Spain
| | - Defu Wang
- Jiangxi Provincial Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology, Nanchang Institute of Technology, Nanchang, China
| | - Nan Zhao
- Jiangxi Provincial Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology, Nanchang Institute of Technology, Nanchang, China
| | - Guomin Huang
- Jiangxi Provincial Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology, Nanchang Institute of Technology, Nanchang, China
| | - Wenfei Liu
- Jiangxi Provincial Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology, Nanchang Institute of Technology, Nanchang, China
| | - Jianping Wu
- Laboratory of Ecology and Evolutionary Biology, Yunnan University, Kunming, China
| | - Shuangxi Zhou
- Department of Biological Sciences, Macquarie University, New South Wales, Australia
| | - Brendan Choat
- Hawkesbury Institute for the Environment, Western Sydney University, Hawkesbury Campus, Richmond, New South Wales, Australia
| | - David T Tissue
- Hawkesbury Institute for the Environment, Western Sydney University, Hawkesbury Campus, Richmond, New South Wales, Australia
- Global Centre for Land-based Innovation, Western Sydney University, Hawkesbury Campus, Richmond, New South Wales, Australia
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27
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Barigah TS, Gyenge JE, Barreto F, Rozenberg P, Fernández ME. Narrow vessels cavitate first during a simulated drought in Eucalyptus camaldulensis. PHYSIOLOGIA PLANTARUM 2021; 173:2081-2090. [PMID: 34523145 DOI: 10.1111/ppl.13556] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 09/06/2021] [Indexed: 06/13/2023]
Abstract
Establishing drying-limits for mortality of different tree species and understanding the anatomical and physiological traits involved is crucial to predict forests' responses to climate change. The xylem of Eucalyptus camaldulensis presents a complex of solitary vessels surrounded by different imperforate tracheary elements and parenchyma that influence, in a poorly known way, its hydraulic functioning. We aimed at describing the dynamics of embolism propagation in this type of xylem, seeking any vessel-size pattern, and unraveling the threshold of xylem embolism leading to nonrecovery after drought in E. camaldulensis. We assigned potted saplings to a protracted water-stress for 70 days. We relied on colorimetric and hydraulic methods to test for links between xylem anatomy and embolism propagation in the main stem. On average, the occurrence of embolism was randomly distributed in the stem xylem, but the probability of embolized vessels was higher than predicted by chance in the narrowest vessels of individuals that experienced low to moderate water-stress. The saplings could recover from severe water-stress if their percentage loss of conductance (PLC) was <77%, but not when the PLC was ˃ 85%. We concluded that, contrary to results reported for most species, the narrowest vessels are the most vulnerable to cavitation in E. camaldulensis, suggesting a lack of tradeoff between xylem efficiency and safety (in response to drought) at the tissue level. These results challenge the well-established paradigm of the effect of vessel size on cavitation, which states that the widest conduits are the most vulnerable to both freeze-thaw and drought-induced cavitation.
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Affiliation(s)
| | - Javier Enrique Gyenge
- CONICET, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
- INTA, Instituto Nacional de Tecnología Agropecuaria, Ecología Forestal, UEDD INTA-CONICET IPADS, Tandil, Argentina
| | - Florencia Barreto
- CONICET, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | | | - María Elena Fernández
- CONICET, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
- INTA, Instituto Nacional de Tecnología Agropecuaria, Ecología Forestal, UEDD INTA-CONICET IPADS, Tandil, Argentina
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28
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Lemaire C, Blackman CJ, Cochard H, Menezes-Silva PE, Torres-Ruiz JM, Herbette S. Acclimation of hydraulic and morphological traits to water deficit delays hydraulic failure during simulated drought in poplar. TREE PHYSIOLOGY 2021; 41:2008-2021. [PMID: 34259313 DOI: 10.1093/treephys/tpab086] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 07/07/2021] [Indexed: 05/27/2023]
Abstract
The capacity of trees to tolerate and survive increasing drought conditions in situ will depend in part on their ability to acclimate (via phenotypic plasticity) key hydraulic and morphological traits that increase drought tolerance and delay the onset of drought-induced hydraulic failure. However, the effect of water-deficit acclimation in key traits that determine time to hydraulic failure (THF) during extreme drought remains largely untested. We measured key hydraulic and morphological traits in saplings of a hybrid poplar grown under well-watered and water-limited conditions. The time for plants to dry-down to critical levels of water stress (90% loss of stem hydraulic conductance), as well as the relative contribution of drought acclimation in each trait to THF, was simulated using a soil-plant hydraulic model (SurEau). Compared with controls, water-limited plants exhibited significantly lower stem hydraulic vulnerability (P50stem), stomatal conductance and total canopy leaf area (LA). Taken together, adjustments in these and other traits resulted in longer modelled THF in water-limited (~160 h) compared with well-watered plants (~50 h), representing an increase of more than 200%. Sensitivity analysis revealed that adjustment in P50stem and LA contributed the most to longer THF in water-limited plants. We observed a high degree of trait plasticity in poplar saplings in response to water-deficit growth conditions, with decreases in stem hydraulic vulnerability and leaf area playing a key role in delaying the onset of hydraulic failure during a simulated drought event. These findings suggest that understanding the capacity of plants to acclimate to antecedent growth conditions will enable better predictions of plant survivorship during future drought.
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Affiliation(s)
- Cédric Lemaire
- Université Clermont Auvergne, INRAE, PIAF, Clermont-Ferrand F-63000, France
| | - Chris J Blackman
- Université Clermont Auvergne, INRAE, PIAF, Clermont-Ferrand F-63000, France
| | - Hervé Cochard
- Université Clermont Auvergne, INRAE, PIAF, Clermont-Ferrand F-63000, France
| | - Paulo Eduardo Menezes-Silva
- Université Clermont Auvergne, INRAE, PIAF, Clermont-Ferrand F-63000, France
- Department of Biology, Goiano Federal Institute of Education, Science and Technology-IF Goiano, Rio Verde, Goiás, Brazil
| | - José M Torres-Ruiz
- Université Clermont Auvergne, INRAE, PIAF, Clermont-Ferrand F-63000, France
| | - Stéphane Herbette
- Université Clermont Auvergne, INRAE, PIAF, Clermont-Ferrand F-63000, France
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Nardini A. Can trees harden up to survive global change-type droughts? TREE PHYSIOLOGY 2021; 41:2004-2007. [PMID: 34542153 DOI: 10.1093/treephys/tpab128] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 09/16/2021] [Indexed: 06/13/2023]
Affiliation(s)
- Andrea Nardini
- Dipartimento di Scienze della Vita, Università di Trieste, Via L. Giorgieri 10, 34127 Trieste, Italy
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30
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Sapes G, Sala A. Relative water content consistently predicts drought mortality risk in seedling populations with different morphology, physiology and times to death. PLANT, CELL & ENVIRONMENT 2021; 44:3322-3335. [PMID: 34251033 DOI: 10.1111/pce.14149] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 07/08/2021] [Indexed: 05/14/2023]
Abstract
Predicted increases in forest drought mortality highlight the need for predictors of incipient drought-induced mortality (DIM) risk that enable proactive large-scale management. Such predictors should be consistent across plants with varying morphology and physiology. Because of their integrative nature, indicators of water status are promising candidates for real-time monitoring of DIM, particularly if they standardize morphological differences among plants. We assessed the extent to which differences in morphology and physiology between Pinus ponderosa populations influence time to mortality and the predictive power of key indicators of DIM risk. Time to incipient mortality differed between populations but occurred at the same relative water content (RWC) and water potential (WP). RWC and WP were accurate predictors of drought mortality risk. These results highlight that variables related to water status capture critical thresholds during DIM and the associated dehydration processes. Both WP and RWC are promising candidates for large-scale assessments of DIM risk. RWC is of special interest because it allows comparisons across different morphologies and can be remotely sensed. Our results offer promise for real-time landscape-level monitoring of DIM and its global impacts in the near term.
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Affiliation(s)
- Gerard Sapes
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
- Department of Ecology, Evolution, and Behavior, University of Minnesota, Saint Paul, Minnesota, USA
| | - Anna Sala
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
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31
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Abate E, Azzarà M, Trifilò P. When Water Availability Is Low, Two Mediterranean Salvia Species Rely on Root Hydraulics. PLANTS (BASEL, SWITZERLAND) 2021; 10:1888. [PMID: 34579421 PMCID: PMC8472023 DOI: 10.3390/plants10091888] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/31/2021] [Accepted: 09/08/2021] [Indexed: 11/16/2022]
Abstract
Increase in severity and frequency of drought events is altering plant community composition, exposing biomes to a higher risk of biodiversity losses. This is exacerbated in the most fragile areas as Mediterranean biome. Thus, identifying plant traits for forecasting species with a high risk of drought-driven mortality is particularly urgent. In the present study, we investigated the drought resistance strategy of two Mediterranean native species: Salvia ceratophylloides Ard. (Sc) and Salvia officinalis L. (So) by considering the impact of drought-driven water content decline on plant hydraulics. Well-watered samples of Sc displayed higher leaf and stemsaturated water content and lower shoot biomass than So samples, but similar root biomass. In response to drought, Sc showed a conservative water use strategy, as the prompt stomatal closure and leaves shedding suggested. A drought-tolerant mechanism was confirmed in So samples. Nevertheless, Sc and So showed similar drought-driven plant hydraulic conductance (Kplant) recover ability. Root hydraulic traits played a key role to reach this goal. Relative water content as well as loss of cell rehydration capability and membrane damages, especially of stem and root, were good proxies of drought-driven Kplant decline.
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Affiliation(s)
| | | | - Patrizia Trifilò
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università di Messina, Viale Ferdinando Stagno d’Alcontres 31, 98166 Messina, Italy; (E.A.); (M.A.)
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32
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Bryant C, Fuenzalida TI, Brothers N, Mencuccini M, Sack L, Binks O, Ball MC. Shifting access to pools of shoot water sustains gas exchange and increases stem hydraulic safety during seasonal atmospheric drought. PLANT, CELL & ENVIRONMENT 2021; 44:2898-2911. [PMID: 33974303 DOI: 10.1111/pce.14080] [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: 11/04/2020] [Revised: 04/30/2021] [Accepted: 05/01/2021] [Indexed: 05/25/2023]
Abstract
Understanding how plants acclimate to drought is crucial for predicting future vulnerability, yet seasonal acclimation of traits that improve drought tolerance in trees remains poorly resolved. We hypothesized that dry season acclimation of leaf and stem traits influencing shoot water storage and hydraulic capacitance would mitigate the drought-associated risks of reduced gas exchange and hydraulic failure in the mangrove Sonneratia alba. By late dry season, availability of stored water had shifted within leaves and between leaves and stems. While whole shoot capacitance remained stable, the symplastic fraction of leaf water increased 86%, leaf capacitance increased 104% and stem capacitance declined 80%. Despite declining plant water potentials, leaf and whole plant hydraulic conductance remained unchanged, and midday assimilation rates increased. Further, the available leaf water between the minimum water potential observed and that corresponding to 50% loss of stem conductance increased 111%. Shifting availability of pools of water, within and between organs, maintained leaf water available to buffer periods of increased photosynthesis and losses in stem hydraulic conductivity, mitigating risks of carbon depletion and hydraulic failure during atmospheric drought. Seasonal changes in access to tissue and organ water may have an important role in drought acclimation and avoidance.
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Affiliation(s)
- Callum Bryant
- Plant Science Division, Research School of Biology, Australian National University, Acton, Australia
| | - Tomas I Fuenzalida
- Plant Science Division, Research School of Biology, Australian National University, Acton, Australia
| | - Nigel Brothers
- Plant Science Division, Research School of Biology, Australian National University, Acton, Australia
| | - Maurizio Mencuccini
- Catalan Institution for Research and Advanced Studies, Barcelona, Spain
- Ecological and Forestry Applications Research Centre, Barcelona, Spain
| | - Lawren Sack
- Department of Ecology and Evolution, University of California Los Angeles, Los Angeles, California, USA
| | - Oliver Binks
- Plant Science Division, Research School of Biology, Australian National University, Acton, Australia
| | - Marilyn C Ball
- Plant Science Division, Research School of Biology, Australian National University, Acton, Australia
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Abate E, Nardini A, Petruzzellis F, Trifilò P. Too dry to survive: Leaf hydraulic failure in two Salvia species can be predicted on the basis of water content. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2021; 166:215-224. [PMID: 34119871 DOI: 10.1016/j.plaphy.2021.05.046] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 05/28/2021] [Indexed: 06/12/2023]
Abstract
Global warming is exposing plants to increased risks of drought-driven mortality. Recent advances suggest that hydraulic failure is a key process leading to plant death, and the identification of simple and reliable proxies of species-specific risk of irreversible hydraulic damage is urgently required. We assessed the predictive power of leaf water content and shrinkage for monitoring leaf hydraulic failure in two Mediterranean native species, Salvia ceratophylloides (Sc) and S. officinalis (So). The study species showed significant differences in relative water content (RWC) thresholds inducing loss of rehydration capacity, as well as leaf hydraulic conductance (KL) impairment. Sc turned out to be more resistant to drought than So. However, Sc and So showed different leaf saturated water content values, so that different RWC values actually corresponded to similar absolute leaf water content. Our findings suggest that absolute leaf water content and leaf water potential, but not RWC, are reliable parameters for predicting the risk of leaf hydraulic impairment of two Salvia species, and their potential risk of irreversible damage under severe drought. Moreover, the lack of any KL decline until the turgor loss point in Sc, coupled to consistent leaf shrinkage, rejects the hypothesis to use leaf shrinkage as a proxy to predict KL vulnerability, at least in species with high leaf capacitance. Robust linear correlations between KL decline and electrolyte leakage measurements suggested a role of membrane damage in driving leaf hydraulic collapse.
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Affiliation(s)
- Elisa Abate
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università di Messina, Viale Ferdinando Stagno d'Alcontres 31, 98166, Messina, Italy
| | - Andrea Nardini
- Dipartimento di Scienze della Vita, Università di Trieste, Via L. Giorgieri 10, 34127, Trieste, Italy
| | - Francesco Petruzzellis
- Dipartimento di Scienze AgroAlimentari, Ambientali e Animali, Università di Udine, Via delle Scienze 91, 33100, Udine, Italy
| | - Patrizia Trifilò
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università di Messina, Viale Ferdinando Stagno d'Alcontres 31, 98166, Messina, Italy.
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