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Creek D, Lamarque LJ, Torres-Ruiz JM, Parise C, Burlett R, Tissue DT, Delzon S. Xylem embolism in leaves does not occur with open stomata: evidence from direct observations using the optical visualization technique. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:1151-1159. [PMID: 31641746 DOI: 10.1093/jxb/erz474] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Accepted: 10/11/2019] [Indexed: 06/10/2023]
Abstract
Drought represents a major abiotic constraint to plant growth and survival. On the one hand, plants keep stomata open for efficient carbon assimilation while, on the other hand, they close them to prevent permanent hydraulic impairment from xylem embolism. The order of occurrence of these two processes (stomatal closure and the onset of leaf embolism) during plant dehydration has remained controversial, largely due to methodological limitations. However, the newly developed optical visualization method now allows concurrent monitoring of stomatal behaviour and leaf embolism formation in intact plants. We used this new approach directly by dehydrating intact saplings of three contrasting tree species and indirectly by conducting a literature survey across a greater range of plant taxa. Our results indicate that increasing water stress generates the onset of leaf embolism consistently after stomatal closure, and that the lag time between these processes (i.e. the safety margin) rises with increasing embolism resistance. This suggests that during water stress, embolism-mediated declines in leaf hydraulic conductivity are unlikely to act as a signal for stomatal down-regulation. Instead, these species converge towards a strategy of closing stomata early to prevent water loss and delay catastrophic xylem dysfunction.
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Affiliation(s)
- Danielle Creek
- Université Clermont-Auvergne, INRA, PIAF, Clermont-Ferrand, France
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | | | | | | | - Regis Burlett
- BIOGECO, INRA, Université de Bordeaux, Pessac, France
| | - David T Tissue
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
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Szejner P, Belmecheri S, Ehleringer JR, Monson RK. Recent increases in drought frequency cause observed multi-year drought legacies in the tree rings of semi-arid forests. Oecologia 2019; 192:241-259. [DOI: 10.1007/s00442-019-04550-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 10/29/2019] [Indexed: 01/07/2023]
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53
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Buckley TN. How do stomata respond to water status? THE NEW PHYTOLOGIST 2019; 224:21-36. [PMID: 31069803 DOI: 10.1111/nph.15899] [Citation(s) in RCA: 195] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 04/25/2019] [Indexed: 05/20/2023]
Abstract
Stomatal responses to humidity, soil moisture and other factors that influence plant water status are critical drivers of photosynthesis, productivity, water yield, ecohydrology and climate forcing, yet we still lack a thorough mechanistic understanding of these responses. Here I review historical and recent advances in stomatal water relations. Clear evidence now implicates a metabolically mediated response to leaf water status ('hydroactive feedback') in stomatal responses to evaporative demand and soil drought, possibly involving abscisic acid production in leaves. Other hypothetical mechanisms involving vapor and heat transport within leaves may contribute to humidity, light and temperature responses, but require further theoretical clarification and experimental validation. Variation and dynamics in hydraulic conductance, particularly within leaves, may contribute to water status responses. Continuing research to fully resolve mechanisms of stomatal responses to water status should focus on several areas: validating and quantifying the mechanism of leaf-based hydroactive feedback, identifying where in leaves water status is actively sensed, clarifying the role of leaf vapor and energy transport in humidity and temperature responses, and verifying foundational but minimally replicated results of stomatal hydromechanics across species. Clarity on these matters promises to deliver modelers with a tractable and reliable mechanistic model of stomatal responses to water status.
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Affiliation(s)
- Thomas N Buckley
- Department of Plant Sciences, University of California, Davis, One Shields Ave, Davis, CA, 95616, USA
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Berry ZC, Espejel X, Williams-Linera G, Asbjornsen H. Linking coordinated hydraulic traits to drought and recovery responses in a tropical montane cloud forest. AMERICAN JOURNAL OF BOTANY 2019; 106:1316-1326. [PMID: 31518000 DOI: 10.1002/ajb2.1356] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 07/25/2019] [Indexed: 06/10/2023]
Abstract
PREMISE Understanding plant hydraulic functioning and water balance during drought has become key in predicting species survival and recovery. However, there are few insightful studies that couple physiological and morphological attributes for many ecosystems, such as the vulnerable Tropical Montane Cloud Forests (TMCF). In this study, we evaluated drought resistance and recovery for saplings for five tree species spanning deciduous to evergreen habits from a Mexican TMCF. METHODS In drought simulations, water was withheld until plants reached species-specific P50 or P88 values (pressures required to induce a 50 or 88% loss in hydraulic conductivity), then they were rewatered. Drought resistance was considered within the isohydric-anisohydric framework and compared to leaf gas exchange, water status, pressure-volume curves, specific leaf area, and stomatal density. RESULTS The TMCF species closed stomata well before significant losses in hydraulic conductivity (isohydric). Yet, despite the coordination of these traits, the traits were not useful for predicting the time needed for the species to reach critical hydraulic thresholds. Instead, maximum photosynthetic rates explained these times, reinforcing the linkage between hydraulic and carbon dynamics. Despite their varying hydraulic conductivities, stomatal responses, and times to hydraulic thresholds, 58 of the 60 study plants recovered after the rewatering. The recovery of photosynthesis and stomatal conductance can be explained by the P50 values and isohydry. CONCLUSIONS This study raises new questions surrounding drought management strategies, recovery processes, and how lethal thresholds are defined. Further studies need to consider the role of water and carbon balance in allowing for both survival and recovery from drought.
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Affiliation(s)
- Z Carter Berry
- Schmid College of Science and Technology, Chapman University, Orange, CA, 92866, USA
| | - Ximena Espejel
- Instituto de Ecología, A.C., Carretera Antigua a Coatepec 351, Xalapa, Veracruz, 91070, México
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55
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Brodribb TJ, Cochard H, Dominguez CR. Measuring the pulse of trees; using the vascular system to predict tree mortality in the 21st century. CONSERVATION PHYSIOLOGY 2019; 7:coz046. [PMID: 31423313 PMCID: PMC6691484 DOI: 10.1093/conphys/coz046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 06/10/2019] [Accepted: 06/18/2019] [Indexed: 06/01/2023]
Abstract
Tree mortality during hot and dry conditions presents a stark reminder of the vulnerability of plant species to climatic extremes. The current global warming trend makes predicting the impacts of hot/dry events on species survival an urgent task; yet, the standard tools for this purpose lack a physiological basis. This review examines a diversity of recent evidence demonstrating how physiological attributes of plant vascular systems can explain not only why trees die during drought, but also their distributional limits according to rainfall. These important advances in the science of plant water transport physiology provide the basis for new hydraulic models that can provide credible predictions of not only how but when, where and which species will be impacted by changes in rainfall and temperature in the future. Applying a recently developed hydraulic model using realistic parameters, we show that even apparently safe mesic forest in central France is predicted to experience major forest mortality before the end of the century.
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Affiliation(s)
- Timothy J Brodribb
- School of Natural Sciences, University of Tasmania, Bag 55 ,Hobart, Tasmania, Australia
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56
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Ruehr NK, Grote R, Mayr S, Arneth A. Beyond the extreme: recovery of carbon and water relations in woody plants following heat and drought stress. TREE PHYSIOLOGY 2019; 39:1285-1299. [PMID: 30924906 PMCID: PMC6703153 DOI: 10.1093/treephys/tpz032] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 01/08/2019] [Accepted: 03/13/2019] [Indexed: 05/19/2023]
Abstract
Plant responses to drought and heat stress have been extensively studied, whereas post-stress recovery, which is fundamental to understanding stress resilience, has received much less attention. Here, we present a conceptual stress-recovery framework with respect to hydraulic and metabolic functioning in woody plants. We further synthesize results from controlled experimental studies following heat or drought events and highlight underlying mechanisms that drive post-stress recovery. We find that the pace of recovery differs among physiological processes. Leaf water potential and abscisic acid concentration typically recover within few days upon rewetting, while leaf gas exchange-related variables lag behind. Under increased drought severity as indicated by a loss in xylem hydraulic conductance, the time for stomatal conductance recovery increases markedly. Following heat stress release, a similar delay in leaf gas exchange recovery has been observed, but the reasons are most likely a slow reversal of photosynthetic impairment and other temperature-related leaf damages, which typically manifest at temperatures above 40 °C. Based thereon, we suggest that recovery of gas exchange is fast following mild stress, while recovery is slow and reliant on the efficiency of repair and regrowth when stress results in functional impairment and damage to critical plant processes. We further propose that increasing stress severity, particular after critical stress levels have been reached, increases the carbon cost involved in reestablishing functionality. This concept can guide future experimental research and provides a base for modeling post-stress recovery of carbon and water relations in trees.
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Affiliation(s)
- Nadine K Ruehr
- Karlsruhe Institute of Technology, Institute of Meteorology and Climate Research—Atmospheric Environmental Research (KIT/IMK-IFU), Garmisch-Partenkirchen, Germany
| | - Rüdiger Grote
- Karlsruhe Institute of Technology, Institute of Meteorology and Climate Research—Atmospheric Environmental Research (KIT/IMK-IFU), Garmisch-Partenkirchen, Germany
| | - Stefan Mayr
- Department of Botany, University of Innsbruck, Innsbruck, Austria
| | - Almut Arneth
- Karlsruhe Institute of Technology, Institute of Meteorology and Climate Research—Atmospheric Environmental Research (KIT/IMK-IFU), Garmisch-Partenkirchen, Germany
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57
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Skelton RP, Anderegg LDL, Papper P, Reich E, Dawson TE, Kling M, Thompson SE, Diaz J, Ackerly DD. No local adaptation in leaf or stem xylem vulnerability to embolism, but consistent vulnerability segmentation in a North American oak. THE NEW PHYTOLOGIST 2019; 223:1296-1306. [PMID: 31059125 DOI: 10.1111/nph.15886] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 04/21/2019] [Indexed: 05/23/2023]
Abstract
Vulnerability to embolism varies between con-generic species distributed along aridity gradients, yet little is known about intraspecific variation and its drivers. Even less is known about intraspecific variation in tissues other than stems, despite results suggesting that roots, stems and leaves can differ in vulnerability. We hypothesized that intraspecific variation in vulnerability in leaves and stems is adaptive and driven by aridity. We quantified leaf and stem vulnerability of Quercus douglasii using the optical technique. To assess contributions of genetic variation and phenotypic plasticity to within-species variation, we quantified the vulnerability of individuals growing in a common garden, but originating from populations along an aridity gradient, as well as individuals from the same wild populations. Intraspecific variation in water potential at which 50% of total embolism in a tissue is observed (P50 ) was explained mostly by differences between individuals (>66% of total variance) and tissues (16%). There was little between-population variation in leaf/stem P50 in the garden, which was not related to site of origin aridity. Unexpectedly, we observed a positive relationship between wild individual stem P50 and aridity. Although there is no local adaptation and only minor phenotypic plasticity in leaf/stem vulnerability in Q. douglasii, high levels of potentially heritable variation within populations or strong environmental selection could contribute to adaptive responses under future climate change.
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Affiliation(s)
- Robert P Skelton
- Department of Integrative Biology, University of California, Berkeley, CA, 94720, USA
| | - Leander D L Anderegg
- Department of Integrative Biology, University of California, Berkeley, CA, 94720, USA
- Carnegie Science, Stanford University, Stanford, CA, 94305, USA
| | - Prahlad Papper
- Department of Integrative Biology, University of California, Berkeley, CA, 94720, USA
| | - Emma Reich
- Department of Integrative Biology, University of California, Berkeley, CA, 94720, USA
| | - Todd E Dawson
- Department of Integrative Biology, University of California, Berkeley, CA, 94720, USA
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, 94720, USA
| | - Matthew Kling
- Department of Integrative Biology, University of California, Berkeley, CA, 94720, USA
| | - Sally E Thompson
- Department of Civil and Environmental Engineering, University of California, Berkeley, CA, 94720, USA
- School of Civil, Environmental and Mining Engineering, University of Western Australia, Perth, 6907, Australia
| | - Jessica Diaz
- Department of Integrative Biology, University of California, Berkeley, CA, 94720, USA
| | - David D Ackerly
- Department of Integrative Biology, University of California, Berkeley, CA, 94720, USA
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, 94720, USA
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58
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Gavinet J, Ourcival JM, Limousin JM. Rainfall exclusion and thinning can alter the relationships between forest functioning and drought. THE NEW PHYTOLOGIST 2019; 223:1267-1279. [PMID: 31006128 DOI: 10.1111/nph.15860] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 04/12/2019] [Indexed: 06/09/2023]
Abstract
Increasing drought caused by the ongoing climate change, and forest management by thinning that aims at mitigating its impact, may modify the current relationships between forest functions and drought intensity and preclude our ability to forecast future ecosystem responses. We used 15 yr of data from an experimental rainfall exclusion (-27% of rainfall) combined with thinning (-30% stand basal area) to investigate differences in the drought-function relationships for each component of above-ground net primary productivity (ANPP) and stand transpiration in a Mediterranean Quercus ilex stand. Rainfall exclusion reduced stand ANPP by 10%, mainly because of lowered leaf and acorn production, whereas wood production remained unaffected. These responses were consistent with the temporal sensitivity to drought among tree organs but revealed an increased allocation to wood. Thinning increased wood and acorn production and reduced the sensitivity of standing wood biomass change to drought. Rainfall exclusion and thinning lowered the intercept of the transpiration-drought relationship as a result of the structural constraints exerted by lower leaf and sapwood area. The results suggest that historical drought-function relationships can be used to infer future drought impacts on stand ANPP but not on water fluxes. Thinning can mitigate drought effects and reduce forest sensitivity to drought.
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Affiliation(s)
- Jordane Gavinet
- CEFE CNRS, 1919 route de Mende, 34293, Montpellier, Cedex 5, France
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59
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Trueba S, Pan R, Scoffoni C, John GP, Davis SD, Sack L. Thresholds for leaf damage due to dehydration: declines of hydraulic function, stomatal conductance and cellular integrity precede those for photochemistry. THE NEW PHYTOLOGIST 2019; 223:134-149. [PMID: 30843202 DOI: 10.1111/nph.15779] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Accepted: 02/18/2019] [Indexed: 05/04/2023]
Abstract
Given increasing water deficits across numerous ecosystems world-wide, it is urgent to understand the sequence of failure of leaf function during dehydration. We assessed dehydration-induced losses of rehydration capacity and maximum quantum yield of the photosystem II (Fv /Fm ) in the leaves of 10 diverse angiosperm species, and tested when these occurred relative to turgor loss, declines of stomatal conductance gs , and hydraulic conductance Kleaf , including xylem and outside xylem pathways for the same study plants. We resolved the sequences of relative water content and leaf water potential Ψleaf thresholds of functional impairment. On average, losses of leaf rehydration capacity occurred at dehydration beyond 50% declines of gs , Kleaf and turgor loss point. Losses of Fv /Fm occurred after much stronger dehydration and were not recovered with leaf rehydration. Across species, tissue dehydration thresholds were intercorrelated, suggesting trait co-selection. Thresholds for each type of functional decline were much less variable across species in terms of relative water content than Ψleaf . The stomatal and leaf hydraulic systems show early functional declines before cell integrity is lost. Substantial damage to the photochemical apparatus occurs at extreme dehydration, after complete stomatal closure, and seems to be irreversible.
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Affiliation(s)
- Santiago Trueba
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
| | - Ruihua Pan
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
- School of Ecology and Environment, Inner Mongolia University, 235 University West Road, Hohhot, Inner Mongolia, 010021, China
| | - Christine Scoffoni
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
- Department of Biological Sciences, California State University Los Angeles, 5151 State University Drive, Los Angeles, CA, 90032, USA
| | - Grace P John
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
- Department of Integrative Biology, University of Texas at Austin, 2415 Speedway, Austin, TX, 78712, USA
| | - Stephen D Davis
- Natural Science Division, Pepperdine University, Malibu, CA, 90263-4321, USA
| | - Lawren Sack
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
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60
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Kannenberg SA, Novick KA, Phillips RP. Anisohydric behavior linked to persistent hydraulic damage and delayed drought recovery across seven North American tree species. THE NEW PHYTOLOGIST 2019; 222:1862-1872. [PMID: 30664253 DOI: 10.1111/nph.15699] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 01/15/2019] [Indexed: 05/08/2023]
Abstract
The isohydry-anisohydry spectrum has become a popular way to characterize plant drought responses and recovery processes. Despite the proven utility of this framework for understanding the interconnected physiological changes plants undergo in response to water stress, new challenges have arisen pertaining to the traits and tradeoffs that underlie this concept. To test the utility of this framework for understanding hydraulic traits, drought physiology and recovery, we applied a 6 wk experimental soil moisture reduction to seven tree species followed by a 6 wk recovery period. Throughout, we measured hydraulic traits and monitored changes in gas exchange, leaf water potential, and hydraulic conductivity. Species' hydraulic traits were not coordinated, as some anisohydric species had surprisingly low resistance to embolism (P50 ) and negative safety margins. In addition to widespread hydraulic damage, these species also experienced reductions in photosynthesis and stem water potential during water stress, and delayed recovery time. Given that we observed no benefit of being anisohydric either during or after drought, our results indicate the need to reconsider the traits and tradeoffs that underlie anisohydric behavior, and to consider the environmental, biological and edaphic processes that could allow this strategy to flourish in forests.
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Affiliation(s)
- Steven A Kannenberg
- School of Biological Sciences, University of Utah, Salt Lake City, UT, 84112, USA
- Department of Biology, Indiana University, Bloomington, IN, 47405, USA
| | - Kimberly A Novick
- School of Public and Environmental Affairs, Indiana University, Bloomington, IN, 47405, USA
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61
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Choat B, Nolf M, Lopez R, Peters JMR, Carins-Murphy MR, Creek D, Brodribb TJ. Non-invasive imaging shows no evidence of embolism repair after drought in tree species of two genera. TREE PHYSIOLOGY 2019; 39:113-121. [PMID: 30137594 DOI: 10.1093/treephys/tpy093] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Accepted: 07/29/2018] [Indexed: 06/08/2023]
Abstract
Drought stress can result in significant impairment of the plant hydraulic system via blockage of xylem conduits by gas emboli. Recovery after drought stress is an essential component of plant survival but is still a poorly understood process. In this study, we examined the capacity of woody species from two genera (Eucalyptus and Quercus) to refill embolized xylem vessels during a cycle of drought and recovery. Observations were made on intact plants of Eucalyptus calmudulensis, E. grandis, E. saligna and Quercus palustris using X-ray microtomography. We found no evidence of an effective xylem refilling mechanism in any of the plant species. Despite rehydration and recovery of plant water potential to near pre-drought levels, embolized vessels were not refilled up to 72 h after rewatering. In E. saligna, water droplets accumulated in previously air-filled vessels for a very small percentage of vessels. However, no instances of complete refilling that would restore embolized vessels to hydraulic function were observed. Our observations suggest that rapid refilling of embolized vessels after drought may not be a wide spread mechanism in woody plants and that embolism formed during drought represents long term cost to the plant hydraulic system.
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Affiliation(s)
- Brendan Choat
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, Australia
| | - Markus Nolf
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, Australia
| | - Rosana Lopez
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, Australia
- PIAF, Institut National dela Recherche Agronomique, UCA, Clermont-Ferrand, France
| | - Jennifer M R Peters
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, Australia
| | | | - Danielle Creek
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, Australia
| | - Timothy J Brodribb
- School of Biological Sciences, University of Tasmania, Hobart, TAS, Australia
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62
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Creek D, Blackman CJ, Brodribb TJ, Choat B, Tissue DT. Coordination between leaf, stem, and root hydraulics and gas exchange in three arid-zone angiosperms during severe drought and recovery. PLANT, CELL & ENVIRONMENT 2018; 41:2869-2881. [PMID: 30106477 DOI: 10.1111/pce.13418] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Accepted: 07/30/2018] [Indexed: 05/13/2023]
Abstract
The ability to resist hydraulic dysfunction in leaves, stems, and roots strongly influences whether plants survive and recover from drought. However, the coordination of hydraulic function among different organs within species and their links to gas exchange during drought and recovery remains understudied. Here, we examine the interaction between gas exchange and hydraulic function in the leaves, stems, and roots of three semiarid evergreen species exposed to a cycle of severe water stress (associated with substantial cavitation) and recovery. In all species, stomatal closure occurred at water potentials well before 50% loss of stem hydraulic conductance, while in two species, leaves and/or roots were more vulnerable than stems. Following soil rewetting, leaf-level photosynthesis (Anet ) returned to prestress levels within 2-4 weeks, whereas stomatal conductance and canopy transpiration were slower to recover. The recovery of Anet was decoupled from the recovery of leaf, stem, and root hydraulics, which remained impaired throughout the recovery period. Our results suggest that in addition to high embolism resistance, early stomatal closure and hydraulic vulnerability segmentation confers drought tolerance in these arid zone species. The lack of substantial embolism refilling within all major organs suggests that vulnerability of the vascular system to drought-induced dysfunction is a defining trait for predicting postdrought recovery.
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Affiliation(s)
- Danielle Creek
- Hawkesbury Institute for the Environment, University of Western Sydney, Penrith, New South Wales, Australia
| | - Chris J Blackman
- Hawkesbury Institute for the Environment, University of Western Sydney, Penrith, New South Wales, Australia
| | - Timothy J Brodribb
- School of Biological Science, University of Tasmania, Hobart, Tasmania, Australia
| | - Brendan Choat
- Hawkesbury Institute for the Environment, University of Western Sydney, Penrith, New South Wales, Australia
| | - David T Tissue
- Hawkesbury Institute for the Environment, University of Western Sydney, Penrith, New South Wales, Australia
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63
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John GP, Henry C, Sack L. Leaf rehydration capacity: Associations with other indices of drought tolerance and environment. PLANT, CELL & ENVIRONMENT 2018; 41:2638-2653. [PMID: 29978483 DOI: 10.1111/pce.13390] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Accepted: 06/19/2018] [Indexed: 06/08/2023]
Abstract
Clarifying the mechanisms of leaf and whole plant drought responses is critical to predict the impacts of ongoing climate change. The loss of rehydration capacity has been used for decades as a metric of leaf dehydration tolerance but has not been compared with other aspects of drought tolerance. We refined methods for quantifying the percent loss of rehydration capacity (PLRC), and for 18 Southern California woody species, we determined the relative water content and leaf water potential at PLRC of 10%, 25%, and 50%, and, additionally, the PLRC at important stages of dehydration including stomatal closure and turgor loss. On average, PLRC of 10% occurred below turgor loss point and at similar water status to 80% decline of stomatal conductance. As hypothesized, the sensitivity to loss of leaf rehydration capacity varied across species, leaf habits, and ecosystems and correlated with other drought tolerance traits, including the turgor loss point and structural traits including leaf mass per area. A new database of PLRC for 89 species from the global literature indicated greater leaf rehydration capacity in ecosystems with lower growing season moisture availability, indicating an adaptive role of leaf cell dehydration tolerance within the complex of drought tolerance traits.
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Affiliation(s)
- Grace P John
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, California, USA
- Department of Integrative Biology, University of Texas at Austin, Austin, Texas, USA
| | - Christian Henry
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, California, USA
| | - Lawren Sack
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, California, USA
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64
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Fontes CG, Dawson TE, Jardine K, McDowell N, Gimenez BO, Anderegg L, Negrón-Juárez R, Higuchi N, Fine PVA, Araújo AC, Chambers JQ. Dry and hot: the hydraulic consequences of a climate change-type drought for Amazonian trees. Philos Trans R Soc Lond B Biol Sci 2018; 373:20180209. [PMID: 30297481 PMCID: PMC6178441 DOI: 10.1098/rstb.2018.0209] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/17/2018] [Indexed: 11/12/2022] Open
Abstract
How plants respond physiologically to leaf warming and low water availability may determine how they will perform under future climate change. In 2015-2016, an unprecedented drought occurred across Amazonia with record-breaking high temperatures and low soil moisture, offering a unique opportunity to evaluate the performances of Amazonian trees to a severe climatic event. We quantified the responses of leaf water potential, sap velocity, whole-tree hydraulic conductance (Kwt), turgor loss and xylem embolism, during and after the 2015-2016 El Niño for five canopy-tree species. Leaf/xylem safety margins (SMs), sap velocity and Kwt showed a sharp drop during warm periods. SMs were negatively correlated with vapour pressure deficit, but had no significant relationship with soil water storage. Based on our calculations of canopy stomatal and xylem resistances, the decrease in sap velocity and Kwt was due to a combination of xylem cavitation and stomatal closure. Our results suggest that warm droughts greatly amplify the degree of trees' physiological stress and can lead to mortality. Given the extreme nature of the 2015-2016 El Niño and that temperatures are predicted to increase, this work can serve as a case study of the possible impact climate warming can have on tropical trees.This article is part of a discussion meeting issue 'The impact of the 2015/2016 El Niño on the terrestrial tropical carbon cycle: patterns, mechanisms and implications'.
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Affiliation(s)
- Clarissa G Fontes
- Department of Integrative Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Todd E Dawson
- Department of Integrative Biology, University of California at Berkeley, Berkeley, CA 94720, USA
- Ecosystem Science Division, Department of Science, Policy and Management, Environmental University of California Berkeley, Berkeley, CA, USA
| | - Kolby Jardine
- Climate Science Department, Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 74, Berkeley, CA 94720, USA
- Ciências de Florestas Tropicais, Instituto Nacional de Pesquisas da Amazônia (INPA), Manaus-AM 69067-375, Brazil
| | - Nate McDowell
- Pacific Northwest National Laboratory, Richland, WA, USA
| | - Bruno O Gimenez
- Ciências de Florestas Tropicais, Instituto Nacional de Pesquisas da Amazônia (INPA), Manaus-AM 69067-375, Brazil
| | - Leander Anderegg
- Department of Integrative Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Robinson Negrón-Juárez
- Climate Science Department, Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 74, Berkeley, CA 94720, USA
| | - Niro Higuchi
- Ciências de Florestas Tropicais, Instituto Nacional de Pesquisas da Amazônia (INPA), Manaus-AM 69067-375, Brazil
| | - Paul V A Fine
- Department of Integrative Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Alessandro C Araújo
- Department of Global Ecology, Carnegie Institution for Science, 260 Panama St., Stanford, CA 94305, USA
- Embrapa Amazônia Oriental, Trav. Dr. Enéas Pinheiro, Belém, Pará 66095-100, Brazil
| | - Jeffrey Q Chambers
- Climate Science Department, Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 74, Berkeley, CA 94720, USA
- Department of Geography, University of California Berkeley, 507 McCone Hall #4740, Berkeley, CA 94720, USA
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65
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Lemoine NP, Griffin-Nolan RJ, Lock AD, Knapp AK. Drought timing, not previous drought exposure, determines sensitivity of two shortgrass species to water stress. Oecologia 2018; 188:965-975. [PMID: 30269254 DOI: 10.1007/s00442-018-4265-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 09/25/2018] [Indexed: 11/26/2022]
Abstract
Climate change will alter global precipitation patterns, making it increasingly important that we understand how ecosystems will be impacted by more frequent and severe droughts. Yet most drought studies examine a single, within-season drought, and we know relatively little about the impacts of multiple droughts that occur within a single growing season. This distinction is important because many plant species are able to acclimate physiologically, such that the effects of multiple droughts on ecosystem function deviate significantly from the effects of cumulative, independent droughts. Unfortunately, we know relatively little about the ability of dominant species to acclimate to drought in drought-sensitive ecosystems like semi-arid grasslands. Here, we tested for physiological acclimation to multiple drought events in two dominant shortgrass steppe species: Bouteloua gracilis (C4) and Elymus elymoides (C3). Neither species exhibited physiological acclimation to drought; leaf water potential, stomatal conductance, and photosynthesis rates were all similarly affected by a single, late period drought and a second, late period drought. Biomass was lowest in plants exposed to two droughts, but this is likely due to the cumulative effects of both an early and late period drought. Our results suggest that late period droughts do exert weaker effects on biomass production of two dominant shortgrass species, but that the weaker effects are due to ontogenetic changes in plant physiology as opposed to physiological acclimation against multiple droughts. As a consequence, current ecosystem models that incorporate grass phenology and seasonal physiology should provide accurate predictions of primary production under future climates.
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Affiliation(s)
- Nathan P Lemoine
- Department of Biology, Colorado State University, Fort Collins, CO, USA.
- Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO, USA.
| | - Robert J Griffin-Nolan
- Department of Biology, Colorado State University, Fort Collins, CO, USA
- Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO, USA
| | - Abigail D Lock
- Department of Biology, Colorado State University, Fort Collins, CO, USA
| | - Alan K Knapp
- Department of Biology, Colorado State University, Fort Collins, CO, USA
- Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO, USA
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66
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Feng X, Ackerly DD, Dawson TE, Manzoni S, Skelton RP, Vico G, Thompson SE. The ecohydrological context of drought and classification of plant responses. Ecol Lett 2018; 21:1723-1736. [DOI: 10.1111/ele.13139] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 04/12/2018] [Accepted: 07/16/2018] [Indexed: 01/20/2023]
Affiliation(s)
- Xue Feng
- Department of Civil, Environmental, and Geo‐Engineering University of Minnesota Minneapolis MN USA
| | - David D. Ackerly
- Department of Integrative Biology University of California Berkeley CA USA
| | - Todd E. Dawson
- Department of Integrative Biology University of California Berkeley CA USA
- Department of Environmental Sciences, Policy, and Management University of California Berkeley CA USA
| | - Stefano Manzoni
- Department of Physical Geography Stockholm University Stockholm Sweden
- Bolin Centre for Climate Research Stockholm Sweden
| | - Rob P. Skelton
- Department of Integrative Biology University of California Berkeley CA USA
| | - Giulia Vico
- Department of Crop Production Ecology Swedish University of Agricultural Sciences (SLU) Uppsala Sweden
| | - Sally E. Thompson
- Department of Civil and Environmental Engineering University of California Berkeley CA USA
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67
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Ding L, Lu Z, Gao L, Guo S, Shen Q. Is Nitrogen a Key Determinant of Water Transport and Photosynthesis in Higher Plants Upon Drought Stress? FRONTIERS IN PLANT SCIENCE 2018; 9:1143. [PMID: 30186291 PMCID: PMC6113670 DOI: 10.3389/fpls.2018.01143] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 07/17/2018] [Indexed: 05/19/2023]
Abstract
Drought stress is a major global issue limiting agricultural productivity. Plants respond to drought stress through a series of physiological, cellular, and molecular changes for survival. The regulation of water transport and photosynthesis play crucial roles in improving plants' drought tolerance. Nitrogen (N, ammonium and nitrate) is an essential macronutrient for plants, and it can affect many aspects of plant growth and metabolic pathways, including water relations and photosynthesis. This review focuses on how drought stress affects water transport and photosynthesis, including the regulation of hydraulic conductance, aquaporin expression, and photosynthesis. It also discusses the cross talk between N, water transport, and drought stress in higher plants.
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Affiliation(s)
- Lei Ding
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, China
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Zhifeng Lu
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, China
| | - Limin Gao
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, China
| | - Shiwei Guo
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, China
| | - Qirong Shen
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, China
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68
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Li X, Blackman CJ, Rymer PD, Quintans D, Duursma RA, Choat B, Medlyn BE, Tissue DT. Xylem embolism measured retrospectively is linked to canopy dieback in natural populations of Eucalyptus piperita following drought. TREE PHYSIOLOGY 2018; 38:1193-1199. [PMID: 29757423 DOI: 10.1093/treephys/tpy052] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 04/18/2018] [Indexed: 06/08/2023]
Abstract
Manipulative experiments have suggested that embolism-induced hydraulic impairment underpins widespread tree mortality during extreme drought, yet in situ evidence is rare. One month after drought-induced leaf and branch dieback was observed in field populations of Eucalyptus piperita Sm. in the Blue Mountains (Australia), we measured the level of native stem embolism and characterized the extent of leaf death in co-occurring dieback and healthy (non-dieback) trees. We found that canopy dieback-affected trees showed significantly higher levels of native embolism (26%) in tertiary order branchlets than healthy trees (11%). Furthermore, there was a significant positive correlation (R2 = 0.51) between the level of leaf death and the level of native embolism recorded in branchlets from dieback-affected trees. This retrospective study suggests that hydraulic failure was the primary mechanism of leaf and branch dieback in response to a natural drought event in the field. It also suggests that post-drought embolism refilling is minimal or absent in this species of eucalypt.
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Affiliation(s)
- Ximeng Li
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, Australia
| | - Chris J Blackman
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, Australia
| | - Paul D Rymer
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, Australia
| | - Desi Quintans
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, Australia
| | - Remko A Duursma
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, Australia
| | - Brendan Choat
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, Australia
| | - Belinda E Medlyn
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, Australia
| | - David T Tissue
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, Australia
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69
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Guzmán-Delgado P, Mason Earles J, Zwieniecki MA. Insight into the physiological role of water absorption via the leaf surface from a rehydration kinetics perspective. PLANT, CELL & ENVIRONMENT 2018; 41:1886-1894. [PMID: 29740843 DOI: 10.1111/pce.13327] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 04/24/2018] [Indexed: 06/08/2023]
Abstract
Soil water transported via the petiole is a primary rehydration pathway for leaves of water-stressed plants. Leaves may also rehydrate by absorbing water via their epidermal surfaces. The mechanisms and physiological relevance of this water pathway, however, remain unclear, as the associated hydraulic properties are unknown. To gain insight into the foliar water absorption process, we compared rehydration kinetics via the petiole and surface of Prunus dulcis and Quercus lobata leaves. Petiole rehydration could be described by a double exponential function suggesting that 2 partly isolated water pools exist in leaves of both species. Surface rehydration could be described by a logistic function, suggesting that leaves behave as a single water pool. Whereas full leaf rehydration via the petiole required approximately 20 min, it took over 150 and 300 min via the surface of P. dulcis and Q. lobata, respectively. Such differences were attributed to the high resistance imposed by the leaf surface and especially the cuticle. The minimum resistance to surface rehydration was estimated to be 6.6 × 102 (P. dulcis) and 2.6 × 103 MPa·m2 ·s·g-1 (Q. lobata), which is remarkably higher than estimated for petiole rehydration. These results are discussed in a physiological context.
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Affiliation(s)
- Paula Guzmán-Delgado
- Department of Plant Sciences, University of California Davis, Davis, CA, 95616, USA
| | - J Mason Earles
- School of Forestry & Environmental Studies, Yale University, New Haven, CT, 06511, USA
| | - Maciej A Zwieniecki
- Department of Plant Sciences, University of California Davis, Davis, CA, 95616, USA
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70
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Flexas J, Carriquí M, Nadal M. Gas exchange and hydraulics during drought in crops: who drives whom? JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:3791-3795. [PMID: 30032258 PMCID: PMC6054177 DOI: 10.1093/jxb/ery235] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Affiliation(s)
- Jaume Flexas
- Research Group in Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears-Instituto de Agroecología y Economía del Agua (INAGEA), Palma, Illes Balears, Spain
| | - Marc Carriquí
- Research Group in Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears-Instituto de Agroecología y Economía del Agua (INAGEA), Palma, Illes Balears, Spain
| | - Miquel Nadal
- Research Group in Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears-Instituto de Agroecología y Economía del Agua (INAGEA), Palma, Illes Balears, Spain
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71
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Blackman CJ, Gleason SM, Cook AM, Chang Y, Laws CA, Westoby M. The links between leaf hydraulic vulnerability to drought and key aspects of leaf venation and xylem anatomy among 26 Australian woody angiosperms from contrasting climates. ANNALS OF BOTANY 2018; 122:59-67. [PMID: 29668853 PMCID: PMC6025239 DOI: 10.1093/aob/mcy051] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 03/18/2018] [Indexed: 05/13/2023]
Abstract
Background and Aims The structural properties of leaf venation and xylem anatomy strongly influence leaf hydraulics, including the ability of leaves to maintain hydraulic function during drought. Here we examined the strength of the links between different leaf venation traits and leaf hydraulic vulnerability to drought (expressed as P50leaf by rehydration kinetics) in a diverse group of 26 woody angiosperm species, representing a wide range of leaf vulnerabilities, from four low-nutrient sites with contrasting rainfall across eastern Australia. Methods For each species we measured key aspects of leaf venation design, xylem anatomy and leaf morphology. We also assessed for the first time the scaling relationships between hydraulically weighted vessel wall thickness (th) and lumen breadth (bh) across vein orders and habitats. Key Results Across species, variation in P50leaf was strongly correlated with the ratio of vessel wall thickness (th) to lumen breadth (bh) [(t/b)h; an index of conduit reinforcement] at each leaf vein order. Concomitantly, the scaling relationship between th and bh was similar across vein orders, with a log-log slope less than 1 indicating greater xylem reinforcement in smaller vessels. In contrast, P50leaf was not related to th and bh individually, to major vein density (Dvmajor) or to leaf size. Principal components analysis revealed two largely orthogonal trait groupings linked to variation in leaf size and drought tolerance. Conclusions Our results indicate that xylem conduit reinforcement occurs throughout leaf venation, and remains closely linked to leaf drought tolerance irrespective of leaf size.
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Affiliation(s)
- Chris J Blackman
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Sean M Gleason
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
- USDA-ARS, Water Management and Systems Research Unit, Fort Collins, CO, USA
| | - Alicia M Cook
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
| | - Yvonne Chang
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
| | - Claire A Laws
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
| | - Mark Westoby
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
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72
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Choat B, Brodribb TJ, Brodersen CR, Duursma RA, López R, Medlyn BE. Triggers of tree mortality under drought. Nature 2018; 558:531-539. [DOI: 10.1038/s41586-018-0240-x] [Citation(s) in RCA: 647] [Impact Index Per Article: 107.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 05/02/2018] [Indexed: 01/08/2023]
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73
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Rodriguez-Dominguez CM, Carins Murphy MR, Lucani C, Brodribb TJ. Mapping xylem failure in disparate organs of whole plants reveals extreme resistance in olive roots. THE NEW PHYTOLOGIST 2018; 218:1025-1035. [PMID: 29528498 DOI: 10.1111/nph.15079] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 02/04/2018] [Indexed: 05/25/2023]
Abstract
The capacity of plant species to resist xylem cavitation is an important determinant of resistance to drought, mortality thresholds, geographic distribution and productivity. Unravelling the role of xylem cavitation vulnerability in plant evolution and adaptation requires a clear understanding of how this key trait varies between the tissues of individuals and between individuals of species. Here, we examine questions of variation within individuals by measuring how cavitation moves between organs of individual plants. Using multiple cameras placed simultaneously on roots, stems and leaves, we were able to record systemic xylem cavitation during drying of individual olive plants. Unlike previous studies, we found a consistent pattern of root > stem > leaf in terms of xylem resistance to cavitation. The substantial variation in vulnerability to cavitation, evident among individuals, within individuals and within tissues of olive seedlings, was coordinated such that plants with more resistant roots also had more resistant leaves. Preservation of root integrity means that roots can continue to supply water for the regeneration of drought-damaged aerial tissues after post-drought rain. Furthermore, coordinated variation in vulnerability between leaf, stem and root in olive plants suggests a strong selective pressure to maintain a fixed order of cavitation during drought.
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Affiliation(s)
| | - Madeline R Carins Murphy
- School of Biological Sciences, University of Tasmania, Private Bag 55, Hobart, Tas., 7001, Australia
| | - Christopher Lucani
- School of Biological Sciences, University of Tasmania, Private Bag 55, Hobart, Tas., 7001, Australia
| | - Timothy J Brodribb
- School of Biological Sciences, University of Tasmania, Private Bag 55, Hobart, Tas., 7001, Australia
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74
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Anderegg WRL, Wolf A, Arango‐Velez A, Choat B, Chmura DJ, Jansen S, Kolb T, Li S, Meinzer FC, Pita P, Resco de Dios V, Sperry JS, Wolfe BT, Pacala S. Woody plants optimise stomatal behaviour relative to hydraulic risk. Ecol Lett 2018; 21:968-977. [DOI: 10.1111/ele.12962] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 02/25/2018] [Accepted: 03/13/2018] [Indexed: 01/06/2023]
Affiliation(s)
| | | | | | - Brendan Choat
- Hawkesbury Institute for the Environment Western Sydney University Penrith 2751 NSW Australia
| | - Daniel J. Chmura
- Institute of Dendrology Polish Academy of Sciences ul. Parkowa 5 62‐035 Kórnik Poland
| | - Steven Jansen
- Institute of Systematic Botany and Ecology Ulm University Albert‐Einstein‐Allee 11 89081 Ulm Germany
| | - Thomas Kolb
- School of Forestry Northern Arizona University Flagstaff AZ 86011 USA
| | - Shan Li
- Institute of Systematic Botany and Ecology Ulm University Albert‐Einstein‐Allee 11 89081 Ulm Germany
- Department of Wood Anatomy and Utilization Research Institute of Wood Industry Chinese Academy of Forestry Beijing 100091 China
| | | | - Pilar Pita
- Technical University of Madrid Madrid Spain
| | - Víctor Resco de Dios
- Department of Crop and Forest Sciences and Agrotecnio Center Universitat de Lleida Lleida 25198 Spain
| | - John S. Sperry
- Department of Biology University of Utah Salt Lake City UT84112 USA
| | | | - Stephen Pacala
- Department of Ecology and Evolutionary Biology Princeton University Princeton NJ 08544 USA
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75
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Karavani A, Boer MM, Baudena M, Colinas C, Díaz-Sierra R, Pemán J, de Luis M, Enríquez-de-Salamanca Á, Resco de Dios V. Fire-induced deforestation in drought-prone Mediterranean forests: drivers and unknowns from leaves to communities. ECOL MONOGR 2018. [DOI: 10.1002/ecm.1285] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Asaf Karavani
- Master Course Mediterranean Forestry and Natural Resources Management; Universitat de Lleida; E25198 Lleida Spain
| | - Matthias M. Boer
- Hawkesbury Institute for the Environment; Western Sydney University; Richmond New South Wales 2753 Australia
| | - Mara Baudena
- Copernicus Institute of Sustainable Development, Environmental Science Group; Utrecht University; P.O. Box 80115 3508 TC Utrecht The Netherlands
| | - Carlos Colinas
- Department of Crop and Forest Sciences-AGROTECNIO Center; Universitat de Lleida; E 25198 Lleida Spain
| | - Rubén Díaz-Sierra
- Mathematical and Fluid Physics Department; Faculty of Sciences; Universidad Nacional de Educación a Distancia; Madrid 28040 Spain
| | - Jesús Pemán
- Department of Crop and Forest Sciences-AGROTECNIO Center; Universitat de Lleida; E 25198 Lleida Spain
| | - Martín de Luis
- Department of Geography and Regional Planning; University of Zaragoza; 50009 Zaragoza Spain
| | - Álvaro Enríquez-de-Salamanca
- Mathematical and Fluid Physics Department; Faculty of Sciences; Universidad Nacional de Educación a Distancia; Madrid 28040 Spain
| | - Víctor Resco de Dios
- Department of Crop and Forest Sciences-AGROTECNIO Center; Universitat de Lleida; E 25198 Lleida Spain
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