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Jacobsen AL, Venturas MD, Hacke UG, Pratt RB. Sap flow through partially embolized xylem vessel networks. PLANT, CELL & ENVIRONMENT 2024; 47:3375-3392. [PMID: 38826042 DOI: 10.1111/pce.14990] [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: 11/14/2023] [Revised: 05/16/2024] [Accepted: 05/18/2024] [Indexed: 06/04/2024]
Abstract
Sap is transported through numerous conduits in the xylem of woody plants along the path from the soil to the leaves. When all conduits are functional, vessel lumen diameter is a strong predictor of hydraulic conductivity. As vessels become embolized, sap movement becomes increasingly affected by factors operating at scales beyond individual conduits, creating resistances that result in hydraulic conductivity diverging from diameter-based estimates. These effects include pit resistances, connectivity, path length, network topology, and vessel or sector isolation. The impact of these factors varies with the level and distribution of emboli within the network, and manifest as alterations in the relationship between the number and diameter of embolized vessels with measured declines in hydraulic conductivity across vulnerability to embolism curves. Divergences between measured conductivity and diameter-based estimates reveal functional differences that arise because of species- and tissue-specific vessel network structures. Such divergences are not uniform, and xylem tissues may diverge in different ways and to differing degrees. Plants regularly operate under nonoptimal conditions and contain numerous embolized conduits. Understanding the hydraulic implications of emboli within a network and the function of partially embolized networks are critical gaps in our understanding of plants occurring within natural environments.
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Affiliation(s)
- Anna L Jacobsen
- Department of Biology, California State University, Bakersfield, California, USA
| | - Martin D Venturas
- Departamento de Sistemas y Recursos Naturales, Universidad Politécnica de Madrid, Madrid, Spain
| | - Uwe G Hacke
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada
| | - Robert Brandon Pratt
- Department of Biology, California State University, Bakersfield, California, USA
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2
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Tang W, Liu X, Liang X, Liu H, Yu K, He P, McAdam S, Zhao H, Ye Q. Hydraulic vulnerability difference between branches and roots increases with environmental aridity. Oecologia 2024; 205:177-190. [PMID: 38772916 DOI: 10.1007/s00442-024-05562-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 05/01/2024] [Indexed: 05/23/2024]
Abstract
The vulnerability of plant xylem to embolism can be described as the water potential at which xylem conductivity is lost by 50% (P50). According to the traditional hypothesis of hydraulic vulnerability segmentation, the difference in vulnerability to embolism between branches and roots is positive (P50 root-branch > 0). It is not clear whether this occurs broadly across species or how segmentation might vary across aridity gradients. We compiled hydraulic and anatomical datasets from branches and roots across 104 woody species (including new measurements from 10 species) in four biomes to investigate the relationships between P50 root-branch and environmental factors associated with aridity. We found a positive P50 root-branch relationship across species, and evidence that P50 root-branch increases with aridity. Branch xylem hydraulic conductivity transitioned from more efficient (e.g., wider conduit, higher hydraulic conductivity) to safer (e.g., narrower conduit, more negative P50) in response to the increase of aridity, while root xylem hydraulic conductivity remained unchanged across aridity gradients. Our results demonstrate that the hydraulic vulnerability difference between branches and roots is more positive in species from arid regions, largely driven by modifications to branch traits.
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Affiliation(s)
- Weize Tang
- Guangdong Provincial Key Laboratory of Applied Botany and Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, South China Botanical Garden, Chinese Academy of Sciences, No. 723, Xingke Road, Tianhe District, Guangzhou, 510650, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiaorong Liu
- Sichuan University of Arts and Science, Tashi Road 519, Dazhou, 635000, China
| | - Xingyun Liang
- Guangdong Provincial Key Laboratory of Applied Botany and Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, South China Botanical Garden, Chinese Academy of Sciences, No. 723, Xingke Road, Tianhe District, Guangzhou, 510650, China
| | - Hui Liu
- Guangdong Provincial Key Laboratory of Applied Botany and Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, South China Botanical Garden, Chinese Academy of Sciences, No. 723, Xingke Road, Tianhe District, Guangzhou, 510650, China
| | - Kailiang Yu
- High Meadows Environmental Institute, Princeton University, Princeton, NJ, USA
| | - Pengcheng He
- Guangdong Provincial Key Laboratory of Applied Botany and Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, South China Botanical Garden, Chinese Academy of Sciences, No. 723, Xingke Road, Tianhe District, Guangzhou, 510650, China
| | - Scott McAdam
- Purdue Center for Plant Biology, Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, USA
| | - Han Zhao
- Guangdong Provincial Key Laboratory of Applied Botany and Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, South China Botanical Garden, Chinese Academy of Sciences, No. 723, Xingke Road, Tianhe District, Guangzhou, 510650, China
| | - Qing Ye
- Guangdong Provincial Key Laboratory of Applied Botany and Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, South China Botanical Garden, Chinese Academy of Sciences, No. 723, Xingke Road, Tianhe District, Guangzhou, 510650, China.
- College of Life Sciences, Gannan Normal University, Ganzhou, 341000, China.
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3
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Fickle JC, Pratt RB, Jacobsen AL. Xylem structure and hydraulic function in roots and stems of chaparral shrub species from high and low elevation in the Sierra Nevada, California. PHYSIOLOGIA PLANTARUM 2023; 175:e13970. [PMID: 37401910 DOI: 10.1111/ppl.13970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 06/16/2023] [Accepted: 06/25/2023] [Indexed: 07/05/2023]
Abstract
Xylem structure and hydraulics were compared between individuals at lower and upper elevation distribution limits for five chaparral shrub species along a steep transect in the southern Sierra Nevada, California, USA. Higher-elevation plants experienced frequent winter freeze-thaw events and increased precipitation. We hypothesized that environmental differences would lead to xylem trait differences between high and low elevations, but predictions were complicated because both water stress (low elevation) and freeze-thaw events (high elevation) may select for similar traits, such as narrow vessel diameter. We found significant changes in the ratio of stem xylem area to leaf area (Huber value) between elevations, with more xylem area required to support leaves at low elevations. Co-occurring species significantly differed in their xylem traits, suggesting diverse strategies to cope with the highly seasonal environment of this Mediterranean-type climate region. Roots were more hydraulically efficient and more vulnerable to embolism relative to stems, potentially due to roots being buffered from freeze-thaw stress, which allows them to maintain wider diameter vessels. Knowledge of the structure and function of both roots and stems is likely important in understanding whole-plant response to environmental gradients.
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Affiliation(s)
- Jaycie C Fickle
- Department of Biology, California State University, Bakersfield, California, USA
- University of Utah, Salt Lake City, Utah, USA
| | - R Brandon Pratt
- Department of Biology, California State University, Bakersfield, California, USA
| | - Anna L Jacobsen
- Department of Biology, California State University, Bakersfield, California, USA
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4
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Isasa E, Link RM, Jansen S, Tezeh FR, Kaack L, Sarmento Cabral J, Schuldt B. Addressing controversies in the xylem embolism resistance-vessel diameter relationship. THE NEW PHYTOLOGIST 2023; 238:283-296. [PMID: 36636783 DOI: 10.1111/nph.18731] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 12/06/2022] [Indexed: 06/17/2023]
Abstract
Although xylem embolism is a key process during drought-induced tree mortality, its relationship to wood anatomy remains debated. While the functional link between bordered pits and embolism resistance is known, there is no direct, mechanistic explanation for the traditional assumption that wider vessels are more vulnerable than narrow ones. We used data from 20 temperate broad-leaved tree species to study the inter- and intraspecific relationship of water potential at 50% loss of conductivity (P50 ) with hydraulically weighted vessel diameter (Dh ) and tested its link to pit membrane thickness (TPM ) and specific conductivity (Ks ) on species level. Embolism-resistant species had thick pit membranes and narrow vessels. While Dh was weakly associated with TPM , the P50 -Dh relationship remained highly significant after accounting for TPM . The interspecific pattern between P50 and Dh was mirrored by a link between P50 and Ks , but there was no evidence for an intraspecific relationship. Our results provide robust evidence for an interspecific P50 -Dh relationship across our species. As a potential cause for the inconsistencies in published P50 -Dh relationships, our analysis suggests differences in the range of trait values covered, and the level of data aggregation (species, tree or sample level) studied.
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Affiliation(s)
- Emilie Isasa
- Ecophysiology and Vegetation Ecology, Julius-von-Sachs-Institute of Biological Sciences, University of Würzburg, Julius-von-Sachs-Platz 3, 97082, Würzburg, Germany
| | - Roman Mathias Link
- Ecophysiology and Vegetation Ecology, Julius-von-Sachs-Institute of Biological Sciences, University of Würzburg, Julius-von-Sachs-Platz 3, 97082, Würzburg, Germany
- Chair of Forest Botany, Institute of Forest Botany and Forest Zoology, Technical University of Dresden, Pienner Str. 7, 01737, Tharandt, Germany
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Fon Robinson Tezeh
- Ecophysiology and Vegetation Ecology, Julius-von-Sachs-Institute of Biological Sciences, University of Würzburg, Julius-von-Sachs-Platz 3, 97082, Würzburg, Germany
| | - Lucian Kaack
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Juliano Sarmento Cabral
- Ecosystem Modeling Group, Center for Computational and Theoretical Biology, University of Würzburg, Klara-Oppenheimer-Weg 32, 97074, Würzburg, Germany
- Biodiversity Modelling and Environmental Change, School of Biosciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Bernhard Schuldt
- Ecophysiology and Vegetation Ecology, Julius-von-Sachs-Institute of Biological Sciences, University of Würzburg, Julius-von-Sachs-Platz 3, 97082, Würzburg, Germany
- Chair of Forest Botany, Institute of Forest Botany and Forest Zoology, Technical University of Dresden, Pienner Str. 7, 01737, Tharandt, Germany
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5
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Lens F, Gleason SM, Bortolami G, Brodersen C, Delzon S, Jansen S. Functional xylem characteristics associated with drought-induced embolism in angiosperms. THE NEW PHYTOLOGIST 2022; 236:2019-2036. [PMID: 36039697 DOI: 10.1111/nph.18447] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 08/03/2022] [Indexed: 06/15/2023]
Abstract
Hydraulic failure resulting from drought-induced embolism in the xylem of plants is a key determinant of reduced productivity and mortality. Methods to assess this vulnerability are difficult to achieve at scale, leading to alternative metrics and correlations with more easily measured traits. These efforts have led to the longstanding and pervasive assumed mechanistic link between vessel diameter and vulnerability in angiosperms. However, there are at least two problems with this assumption that requires critical re-evaluation: (1) our current understanding of drought-induced embolism does not provide a mechanistic explanation why increased vessel width should lead to greater vulnerability, and (2) the most recent advancements in nanoscale embolism processes suggest that vessel diameter is not a direct driver. Here, we review data from physiological and comparative wood anatomy studies, highlighting the potential anatomical and physicochemical drivers of embolism formation and spread. We then put forward key knowledge gaps, emphasising what is known, unknown and speculation. A meaningful evaluation of the diameter-vulnerability link will require a better mechanistic understanding of the biophysical processes at the nanoscale level that determine embolism formation and spread, which will in turn lead to more accurate predictions of how water transport in plants is affected by drought.
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Affiliation(s)
- Frederic Lens
- Naturalis Biodiversity Center, PO Box 9517, 2300 RA, Leiden, the Netherlands
- Leiden University, Institute of Biology Leiden, Plant Sciences, Sylviusweg 72, 2333 BE, Leiden, the Netherlands
| | - Sean M Gleason
- Water Management and Systems Research Unit, United States Department of Agriculture, Agricultural Research Service, Fort Collins, CO, 80526, USA
| | - Giovanni Bortolami
- Naturalis Biodiversity Center, PO Box 9517, 2300 RA, Leiden, the Netherlands
| | - Craig Brodersen
- School of the Environment, Yale University, New Haven, CT, 06511, USA
| | - Sylvain Delzon
- University of Bordeaux, INRAE, BIOGECO, 33615, Pessac, France
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, D-89081, Ulm, Germany
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Lübbe T, Lamarque LJ, Delzon S, Torres Ruiz JM, Burlett R, Leuschner C, Schuldt B. High variation in hydraulic efficiency but not xylem safety between roots and branches in four temperate broad‐leaved tree species. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13975] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Torben Lübbe
- Plant Ecology Albrecht von Haller Institute for Plant Sciences University of Goettingen Goettingen Germany
| | - Laurent J. Lamarque
- Département des Sciences de l'environnement Université du Québec à Trois‐Rivières Trois‐Rivières QC Canada
- University of Bordeaux INRAE BIOGECO Pessac France
| | | | | | | | - Christoph Leuschner
- Plant Ecology Albrecht von Haller Institute for Plant Sciences University of Goettingen Goettingen Germany
| | - Bernhard Schuldt
- Plant Ecology Albrecht von Haller Institute for Plant Sciences University of Goettingen Goettingen Germany
- Julius‐von‐Sachs‐Institute of Biological Sciences, Ecophysiology and Vegetation Ecology University of Würzburg Würzburg Germany
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7
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Pratt RB, Tobin MF, Jacobsen AL, Traugh CA, De Guzman ME, Hayes CC, Toschi HS, MacKinnon ED, Percolla MI, Clem ME, Smith PT. Starch storage capacity of sapwood is related to dehydration avoidance during drought. AMERICAN JOURNAL OF BOTANY 2021; 108:91-101. [PMID: 33349932 DOI: 10.1002/ajb2.1586] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 09/22/2020] [Indexed: 05/26/2023]
Abstract
PREMISE The xylem tissue of plants performs three principal functions: transport of water, support of the plant body, and nutrient storage. Tradeoffs may arise because different structural requirements are associated with different functions or because suites of traits are under selection that relate to resource acquisition, use, and turnover. The structural and functional basis of xylem storage is not well established. We hypothesized that greater starch storage would be associated with greater sapwood parenchyma and reduced fibers, which would compromise resistance to xylem tensions during dehydration. METHODS We measured cavitation resistance, minimum water potential, starch content, and sapwood parenchyma and fiber area in 30 species of southern California chaparral shrubs (evergreen and deciduous). RESULTS We found that species storing greater starch within their xylem tended to avoid dehydration and were less cavitation resistant, and this was supported by phylogenetic independent contrasts. Greater sapwood starch was associated with greater parenchyma area and reduced fiber area. For species without living fibers, the associations with parenchyma were stronger, suggesting that living fibers may expand starch storage capacity while also contributing to the support function of the vascular tissue. Drought-deciduous species were associated with greater dehydration avoidance than evergreens. CONCLUSIONS Evolutionary forces have led to an association between starch storage and dehydration resistance as part of an adaptive suite of traits. We found evidence for a tradeoff between tissue mechanical traits and starch storage; moreover, the evolution of novel strategies, such as starch-storing living fibers, may mitigate the strength of this tradeoff.
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Affiliation(s)
- R Brandon Pratt
- California State University, Bakersfield, Department of Biology, Bakersfield, California, 93311, USA
| | - Michael F Tobin
- University of Houston-Downtown, Department of Natural Sciences, One Main Street, Houston, Texas, 77002, USA
| | - Anna L Jacobsen
- California State University, Bakersfield, Department of Biology, Bakersfield, California, 93311, USA
| | - Courtney A Traugh
- California State University, Bakersfield, Department of Biology, Bakersfield, California, 93311, USA
| | - Mark E De Guzman
- California State University, Bakersfield, Department of Biology, Bakersfield, California, 93311, USA
| | - Christine C Hayes
- California State University, Bakersfield, Department of Biology, Bakersfield, California, 93311, USA
| | - Hayden S Toschi
- California State University, Bakersfield, Department of Biology, Bakersfield, California, 93311, USA
| | - Evan D MacKinnon
- California State University, Bakersfield, Department of Biology, Bakersfield, California, 93311, USA
| | - Marta I Percolla
- California State University, Bakersfield, Department of Biology, Bakersfield, California, 93311, USA
| | - Michael E Clem
- California State University, Bakersfield, Department of Biology, Bakersfield, California, 93311, USA
| | - Paul T Smith
- California State University, Bakersfield, Department of Biology, Bakersfield, California, 93311, USA
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8
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Peters JMR, Gauthey A, Lopez R, Carins-Murphy MR, Brodribb TJ, Choat B. Non-invasive imaging reveals convergence in root and stem vulnerability to cavitation across five tree species. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:6623-6637. [PMID: 32822502 PMCID: PMC7586747 DOI: 10.1093/jxb/eraa381] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 08/18/2020] [Indexed: 05/08/2023]
Abstract
Root vulnerability to cavitation is challenging to measure and under-represented in current datasets. This gap limits the precision of models used to predict plant responses to drought because roots comprise the critical interface between plant and soil. In this study, we measured vulnerability to drought-induced cavitation in woody roots and stems of five tree species (Acacia aneura, Cedrus deodara, Eucalyptus crebra, Eucalytus saligna, and Quercus palustris) with a wide range of xylem anatomies. X-ray microtomography was used to visualize the accumulation of xylem embolism in stems and roots of intact plants that were naturally dehydrated to varying levels of water stress. Vulnerability to cavitation, defined as the water potential causing a 50% loss of hydraulic function (P50), varied broadly among the species (-4.51 MPa to -11.93 MPa in stems and -3.13 MPa to -9.64 MPa in roots). The P50 of roots and stems was significantly related across species, with species that had more vulnerable stems also having more vulnerable roots. While there was strong convergence in root and stem vulnerability to cavitation, the P50 of roots was significantly higher than the P50 of stems in three species. However, the difference in root and stem vulnerability for these species was small; between 1% and 31% of stem P50. Thus, while some differences existed between organs, roots were not dramatically more vulnerable to embolism than stems, and the differences observed were less than those reported in previous studies. Further study is required to evaluate the vulnerability across root orders and to extend these conclusions to a greater number of species and xylem functional types.
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Affiliation(s)
- Jennifer M R Peters
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, Australia
- Oak Ridge National Laboratory, Climate Change Science Institute & Environmental Science Division, Oak Ridge, TN, USA
| | - Alice Gauthey
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, Australia
| | - Rosana Lopez
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, Australia
- Departamento de Sistemas y Recursos Naturales. Universidad Politécnica de Madrid, Ciudad Universitaria, Madrid, Spain
| | | | - Timothy J Brodribb
- School of Biological Sciences, University of Tasmania, Hobart, TAS, Australia
| | - Brendan Choat
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, Australia
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9
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Brunetti C, Savi T, Nardini A, Loreto F, Gori A, Centritto M. Changes in abscisic acid content during and after drought are related to carbohydrate mobilization and hydraulic recovery in poplar stems. TREE PHYSIOLOGY 2020; 40:1043-1057. [PMID: 32186735 DOI: 10.1093/treephys/tpaa032] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Revised: 02/26/2020] [Accepted: 03/13/2020] [Indexed: 06/10/2023]
Abstract
Drought compromises plant's ability to replace transpired water vapor with water absorbed from the soil, leading to extensive xylem dysfunction and causing plant desiccation and death. Short-term plant responses to drought rely on stomatal closure, and on the plant's ability to recover hydraulic functioning after drought relief. We hypothesize a key role for abscisic acid (ABA) not only in the control of stomatal aperture, but also in hydraulic recovery. Young plants of Populus nigra L. were used to investigate possible relationships among ABA, non-structural carbohydrates (NSC) and xylem hydraulic function under drought and after re-watering. In Populus nigra L. plants subjected to drought, water transport efficiency and hydraulic recovery after re-watering were monitored by measuring the percentage loss of hydraulic conductivity (PLC) and stem specific hydraulic conductivity (Kstem). In the same plants ABA and NSC were quantified in wood and bark. Drought severely reduced stomatal conductance (gL) and markedly increased the PLC. Leaf and stem water potential, and stem hydraulic efficiency fully recovered within 24 h after re-watering, but gL values remained low. After re-watering, we found significant correlations between changes in ABA content and hexoses concentration both in wood and bark. Our findings suggest a role for ABA in the regulation of stem carbohydrate metabolism and starch mobilization upon drought relief, possibly promoting the restoration of xylem transport capacity.
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Affiliation(s)
- Cecilia Brunetti
- National Research Council of Italy, Institute for Sustainable Plant Protection, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Florence), Italy
| | - Tadeja Savi
- University of Natural Resources and Life Sciences, Institute of Botany, Department of Integrative Biology and Biodiversity Research, BOKU, Gregor-Mendel-Straße 33, 1190, Vienna, Austria Austria
| | - Andrea Nardini
- Dipartimento di Scienze della Vita, Università di Trieste, Via L. Giorgieri 10, 34127 Trieste, Italy
| | - Francesco Loreto
- National Research Council of Italy, Department of Biology, Agriculture and Food Sciences, Piazzale Aldo Moro 7, 00185 Roma, Italy
| | - Antonella Gori
- Department of Agri-Food Production and Environmental Sciences, University of Florence, Viale delle Idee 30, 50019 Sesto Fiorentino (Florence), Italy
| | - Mauro Centritto
- National Research Council of Italy, Institute for Sustainable Plant Protection, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Florence), Italy
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10
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Halis Y, Benhaddya ML, Bensaha H, Senoussi MM. How do newly matured vessels start conducting water? The significance of lateral pathways for connecting newly matured vessels to the transpiration stream. TREE PHYSIOLOGY 2019; 39:641-649. [PMID: 30597081 DOI: 10.1093/treephys/tpy127] [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: 08/13/2018] [Revised: 10/15/2018] [Accepted: 10/30/2018] [Indexed: 06/09/2023]
Abstract
Despite the long history of research on xylem structure and function, there are no reports in the literature explaining how xylem vessel elements began conducting water just after their maturation. This study was conducted to demonstrate the anatomical arrangement of newly matured vessels, looking specifically for the first pathways connecting newly matured vessels to the transpiration stream. Using the developing stems of Paraserianthes lophantha (Willd.) I.C.Nielsen as the experimental system, the course of vessel differentiation and maturation along the developing bundles was followed by using the dye-pressure method. Water pathways from newly matured vessels to other functioning vessels were directly visualized by the technique of single-vessel dye injection. Some isolated newly matured vessels from the transpiration stream were detected using two apoplastic tracers. The results of this study converge to support the hypothesis that the movement of water in the newly matured vessels depends completely on lateral contacts with other functioning vessels via vessel-to-vessel paths or vessel relays. In cases where the lateral pathways were absent, the flow within the newly matured vessels was substantially blocked resulting in a significant hydraulic isolation of the newly matured vessels. These results might contribute to a better understanding of the pattern of water movement within the developing xylem systems, and underscore that xylem vessels start conducting water through lateral transport, although their primary function is the axial transport.
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Affiliation(s)
- Youcef Halis
- Scientific and Technical Research Centre for Arid Areas (CRSTRA), Biophysical Station, Nezla, Touggourt, Algeria
| | - Mohammed L Benhaddya
- Scientific and Technical Research Centre for Arid Areas (CRSTRA), Biophysical Station, Nezla, Touggourt, Algeria
| | - Hocine Bensaha
- Unité de Recherche Appliquée en Énergies Renouvelables, URAER, Centre de Développement des Énergies Renouvelables, CDER, Ghardaïa, Algeria
| | - Mohamed M Senoussi
- Laboratory of Biomolecules and Plant Amelioration, Larbi Benmhidi University of Oum El Bouaghi, Constantine Road, Algeria
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11
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Qaderi MM, Martel AB, Dixon SL. Environmental Factors Influence Plant Vascular System and Water Regulation. PLANTS 2019; 8:plants8030065. [PMID: 30875945 PMCID: PMC6473727 DOI: 10.3390/plants8030065] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 02/28/2019] [Accepted: 03/11/2019] [Indexed: 11/16/2022]
Abstract
Developmental initiation of plant vascular tissue, including xylem and phloem, from the vascular cambium depends on environmental factors, such as temperature and precipitation. Proper formation of vascular tissue is critical for the transpiration stream, along with photosynthesis as a whole. While effects of individual environmental factors on the transpiration stream are well studied, interactive effects of multiple stress factors are underrepresented. As expected, climate change will result in plants experiencing multiple co-occurring environmental stress factors, which require further studies. Also, the effects of the main climate change components (carbon dioxide, temperature, and drought) on vascular cambium are not well understood. This review aims at synthesizing current knowledge regarding the effects of the main climate change components on the initiation and differentiation of vascular cambium, the transpiration stream, and photosynthesis. We predict that combined environmental factors will result in increased diameter and density of xylem vessels or tracheids in the absence of water stress. However, drought may decrease the density of xylem vessels or tracheids. All interactive combinations are expected to increase vascular cell wall thickness, and therefore increase carbon allocation to these tissues. A comprehensive study of the effects of multiple environmental factors on plant vascular tissue and water regulation should help us understand plant responses to climate change.
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Affiliation(s)
- Mirwais M Qaderi
- Department of Biology, Mount Saint Vincent University, 166 Bedford Highway, Halifax, NS B3M 2J6, Canada.
- Department of Biology, Saint Mary's University, 923 Robie Street, Halifax, NS B3H 3C3, Canada.
| | - Ashley B Martel
- Department of Biology, Saint Mary's University, 923 Robie Street, Halifax, NS B3H 3C3, Canada.
| | - Sage L Dixon
- Department of Biology, Mount Saint Vincent University, 166 Bedford Highway, Halifax, NS B3M 2J6, Canada.
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Wason JW, Anstreicher KS, Stephansky N, Huggett BA, Brodersen CR. Hydraulic safety margins and air-seeding thresholds in roots, trunks, branches and petioles of four northern hardwood trees. THE NEW PHYTOLOGIST 2018; 219:77-88. [PMID: 29663388 DOI: 10.1111/nph.15135] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 02/28/2018] [Indexed: 05/23/2023]
Abstract
During drought, xylem sap pressures can approach or exceed critical thresholds where gas embolisms form and propagate through the xylem network, leading to systemic hydraulic dysfunction. The vulnerability segmentation hypothesis (VSH) predicts that low-investment organs (e.g. leaf petioles) should be more vulnerable to embolism spread compared to high-investment, perennial organs (e.g. trunks, stems), as a means of mitigating embolism spread and excessive negative pressures in the perennial organs. We tested this hypothesis by measuring air-seeding thresholds using the single-vessel air-injection method and calculating hydraulic safety margins in four northern hardwood tree species of the northeastern United States, in both saplings and canopy height trees, and at five points along the soil-plant-atmosphere continuum. Acer rubrum was the most resistant to air-seeding and generally supported the VSH. However, Fagus grandifolia, Fraxinus americana and Quercus rubra showed little to no variation in air-seeding thresholds across organ types within each species. Leaf-petiole xylem operated at water potentials close to or exceeding their hydraulic safety margins in all species, whereas roots, trunks and stems of A. rubrum, F. grandifolia and Q. rubra operated within their safety margins, even during the third-driest summer in the last 100 yr.
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Affiliation(s)
- Jay W Wason
- School of Forestry & Environmental Studies, Yale University, New Haven, CT, 06511, USA
| | | | | | - Brett A Huggett
- Department of Biology, Bates College, Lewiston, ME, 04240, USA
| | - Craig R Brodersen
- School of Forestry & Environmental Studies, Yale University, New Haven, CT, 06511, USA
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13
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Cuneo IF, Knipfer T, Mandal P, Brodersen CR, McElrone AJ. Water uptake can occur through woody portions of roots and facilitates localized embolism repair in grapevine. THE NEW PHYTOLOGIST 2018; 218:506-516. [PMID: 29460963 DOI: 10.1111/nph.15032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 12/23/2017] [Indexed: 06/08/2023]
Abstract
Water acquisition is thought to be limited to the unsuberized surface located close to root tips. However, there are recurring periods when the unsuberized surfaces are limited in woody root systems, and radial water uptake across the bark of woody roots might play an important physiological role in hydraulic functioning. Using X-ray microcomputed tomography (microCT) and hydraulic conductivity measurements (Lpr ), we examined water uptake capacity of suberized woody roots in vivo and in excised samples. Bark hydration in grapevine woody roots occurred quickly upon exposure to water (c. 4 h). Lpr measurements through the bark of woody roots showed that it is permeable to water and becomes more so upon wetting. After bark hydration, microCT analysis showed that absorbed water was utilized to remove embolism locally, where c. 20% of root xylem vessels refilled completely within 15 h. Embolism removal did not occur in control roots without water. Water uptake through the bark of woody roots probably plays an important role when unsuberized tissue is scarce/absent, and would be particularly relevant following large irrigation events or in late winter when soils are saturated, re-establishing hydraulic functionality before bud break.
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Affiliation(s)
- Italo F Cuneo
- Escuela de Agronomía, Pontificia Universidad Católica de Valparaíso, Quillota 2260000, Chile
| | - Thorsten Knipfer
- Department of Viticulture and Enology, University of California, Davis, CA 95618, USA
| | - Pratiti Mandal
- Advanced Light Source, Lawrence Berkeley Laboratory, Berkeley, CA 94720, USA
| | - Craig R Brodersen
- School of Forestry & Environmental Studies, Yale University, New Haven, CT 06511, USA
| | - Andrew J McElrone
- Department of Viticulture and Enology, University of California, Davis, CA 95618, USA
- Crops Pathology and Genetics Research Unit, USDA-ARS, Davis, CA 95618, USA
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14
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Wason JW, Huggett BA, Brodersen CR. MicroCT imaging as a tool to study vessel endings in situ. AMERICAN JOURNAL OF BOTANY 2017; 104:1424-1430. [PMID: 29885240 DOI: 10.3732/ajb.1700199] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 08/16/2017] [Indexed: 06/08/2023]
Abstract
PREMISE OF THE STUDY Despite the strong influence of the frequency and distribution of vessel endings on both hydraulic safety and efficiency, detailed anatomical descriptions or measurements of these structures are generally lacking. METHODS Here we used high-resolution x-ray microcomputed tomography (microCT) to identify and describe xylem vessel endings within Acer rubrum root segments (1.0-2.1 mm diameter, ∼2 mm long). We then compared vessel-lumen diameter, pit density, vessel element length, and perforation plate angle between non-ending vessels (those that traverse an entire segment) and those that end within a segment using three-dimensional image analysis. KEY RESULTS We found 214 vessel endings, 37 complete vessels, and 385 non-ending vessels within four A. rubrum root segments. Vessels that ended within the segments tended to have more acute perforation plate angles and had a smaller diameter than those that did not end within the segments. Most vessel diameters tapered within the last few vessel elements, but the perforation plate angle apparently changed over longer distances. Intervessel pit density and vessel element length did not differ between ending and non-ending vessels. CONCLUSIONS Vessel endings were surprisingly frequent in A. rubrum roots despite the common perception that root vessels are longer than vessels in other tissues. MicroCT proved to be a useful tool for studying the three-dimensional arrangement of vessel endings within xylem networks, and these data will be helpful in developing a better understanding of vessel ending microstructure and function.
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Affiliation(s)
- Jay W Wason
- School of Forestry and Environmental Studies, Yale University, 370 Prospect St., New Haven, Connecticut, 06511 USA
| | - Brett A Huggett
- Department of Biology, Bates College, 44 Campus Avenue, Lewiston, Maine 04240 USA
| | - Craig R Brodersen
- School of Forestry and Environmental Studies, Yale University, 370 Prospect St., New Haven, Connecticut, 06511 USA
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15
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Torres-Ruiz JM, Cochard H, Choat B, Jansen S, López R, Tomášková I, Padilla-Díaz CM, Badel E, Burlett R, King A, Lenoir N, Martin-StPaul NK, Delzon S. Xylem resistance to embolism: presenting a simple diagnostic test for the open vessel artefact. THE NEW PHYTOLOGIST 2017; 215:489-499. [PMID: 28467616 DOI: 10.1111/nph.14589] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Accepted: 03/28/2017] [Indexed: 05/21/2023]
Abstract
Xylem vulnerability to embolism represents an essential trait for the evaluation of the impact of hydraulics in plant function and ecology. The standard centrifuge technique is widely used for the construction of vulnerability curves, although its accuracy when applied to species with long vessels remains under debate. We developed a simple diagnostic test to determine whether the open-vessel artefact influences centrifuge estimates of embolism resistance. Xylem samples from three species with differing vessel lengths were exposed to less negative xylem pressures via centrifugation than the minimum pressure the sample had previously experienced. Additional calibration was obtained from non-invasive measurement of embolism on intact olive plants by X-ray microtomography. Results showed artefactual decreases in hydraulic conductance (k) for samples with open vessels when exposed to a less negative xylem pressure than the minimum pressure they had previously experienced. X-Ray microtomography indicated that most of the embolism formation in olive occurs at xylem pressures below -4.0 MPa, reaching 50% loss of hydraulic conductivity at -5.3 MPa. The artefactual reductions in k induced by centrifugation underestimate embolism resistance data of species with long vessels. A simple test is suggested to avoid this open vessel artefact and to ensure the reliability of this technique in future studies.
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Affiliation(s)
| | - Hervé Cochard
- PIAF, INRA, University of Clermont-Auvergne, 63100, Clermont-Ferrand, France
| | - Brendan Choat
- Western Sydney University, Hawkesbury Institute for the Environment, Richmond, NSW, 2753, Australia
| | - Steven Jansen
- Ulm University, Institute of Systematic Botany and Ecology, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Rosana López
- PIAF, INRA, University of Clermont-Auvergne, 63100, Clermont-Ferrand, France
- Western Sydney University, Hawkesbury Institute for the Environment, Richmond, NSW, 2753, Australia
| | - Ivana Tomášková
- Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Kamýcká 129, 165 00, Praha 6 - Suchdol, Czech Republic
| | - Carmen M Padilla-Díaz
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS, CSIC), Avenida Reina Mercedes, 10, 41012, Sevilla, Spain
| | - Eric Badel
- PIAF, INRA, University of Clermont-Auvergne, 63100, Clermont-Ferrand, France
| | - Regis Burlett
- BIOGECO, INRA, University of Bordeaux, 33615, Pessac, France
| | - Andrew King
- Synchrotron SOLEIL, L'Orme de Merisiers, 91190 Saint-Aubin - BP48, Gif-sur-Yvette Cedex, France
| | - Nicolas Lenoir
- CNRS, University of Bordeaux, UMS 3626 Placamat, F-33608, Pessac, France
| | | | - Sylvain Delzon
- BIOGECO, INRA, University of Bordeaux, 33615, Pessac, France
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16
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Venturas MD, Sperry JS, Hacke UG. Plant xylem hydraulics: What we understand, current research, and future challenges. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2017; 59:356-389. [PMID: 28296168 DOI: 10.1111/jipb.12534] [Citation(s) in RCA: 159] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 03/09/2017] [Indexed: 05/22/2023]
Abstract
Herein we review the current state-of-the-art of plant hydraulics in the context of plant physiology, ecology, and evolution, focusing on current and future research opportunities. We explain the physics of water transport in plants and the limits of this transport system, highlighting the relationships between xylem structure and function. We describe the great variety of techniques existing for evaluating xylem resistance to cavitation. We address several methodological issues and their connection with current debates on conduit refilling and exponentially shaped vulnerability curves. We analyze the trade-offs existing between water transport safety and efficiency. We also stress how little information is available on molecular biology of cavitation and the potential role of aquaporins in conduit refilling. Finally, we draw attention to how plant hydraulic traits can be used for modeling stomatal responses to environmental variables and climate change, including drought mortality.
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Affiliation(s)
- Martin D Venturas
- Department of Biology, University of Utah, 257 S 1400E, Salt Lake City, UT, 84112, USA
| | - John S Sperry
- Department of Biology, University of Utah, 257 S 1400E, Salt Lake City, UT, 84112, USA
| | - Uwe G Hacke
- Department of Renewable Resources, University of Alberta, Edmonton, AB, T6G 2E3, Canada
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17
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Nardini A, Savi T, Trifilò P, Lo Gullo MA. Drought Stress and the Recovery from Xylem Embolism in Woody Plants. PROGRESS IN BOTANY VOL. 79 2017. [DOI: 10.1007/124_2017_11] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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18
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Jacobsen AL, Tobin MF, Toschi HS, Percolla MI, Pratt RB. Structural determinants of increased susceptibility to dehydration-induced cavitation in post-fire resprouting chaparral shrubs. PLANT, CELL & ENVIRONMENT 2016; 39:2473-2485. [PMID: 27423060 DOI: 10.1111/pce.12802] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 07/06/2016] [Accepted: 07/11/2016] [Indexed: 06/06/2023]
Abstract
It is well established that transpiration and photosynthetic rates generally increase in resprouting shoots after fire in chaparral shrublands. By contrast, little is known about how plant hydraulic function varies during this same recovery period. We hypothesized that vascular traits, both functional and structural, would also shift in order to support this heightened level of gas exchange and growth. We examined stem xylem-specific hydraulic conductivity (Ks ) and resistance to cavitation (P50 ) for eight chaparral shrub species as well as several potential xylem structural determinants of hydraulic function and compared established unburned plants and co-occurring post-fire resprouting plants. Unburned plants were generally more resistant to cavitation than resprouting plants, but the two groups did not differ in Ks . Resprouting plants had altered vessel structure compared with unburned plants, with resprouting plants having both wider diameter vessels and higher inter-vessel pit density. For biomechanics, unburned plants had both stronger and denser stem xylem tissue than resprouting plants. Shifts in hydraulic structure and function resulted in resprouting plants being more vulnerable to dehydration. The interaction between time since disturbance (i.e. resprouting versus established stands) and drought may complicate attempts to predict mortality risk of resprouting plants.
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Affiliation(s)
- Anna L Jacobsen
- Department of Biology, California State University, Bakersfield, 9001 Stockdale Highway, Bakersfield, CA, 93311, USA.
| | - Michael F Tobin
- Department of Natural Sciences, University of Houston-Downtown, One Main Street, Houston, TX, 77002, USA
| | - Hayden S Toschi
- Department of Biology, California State University, Bakersfield, 9001 Stockdale Highway, Bakersfield, CA, 93311, USA
| | - Marta I Percolla
- Department of Biology, California State University, Bakersfield, 9001 Stockdale Highway, Bakersfield, CA, 93311, USA
| | - R Brandon Pratt
- Department of Biology, California State University, Bakersfield, 9001 Stockdale Highway, Bakersfield, CA, 93311, USA
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19
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Venturas MD, Rodriguez-Zaccaro FD, Percolla MI, Crous CJ, Jacobsen AL, Pratt RB. Single vessel air injection estimates of xylem resistance to cavitation are affected by vessel network characteristics and sample length. TREE PHYSIOLOGY 2016; 36:1247-1259. [PMID: 27358206 DOI: 10.1093/treephys/tpw055] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 05/30/2016] [Indexed: 06/06/2023]
Abstract
Xylem resistance to cavitation is an important trait that is related to the ecology and survival of plant species. Vessel network characteristics, such as vessel length and connectivity, could affect the spread of emboli from gas-filled vessels to functional ones, triggering their cavitation. We hypothesized that the cavitation resistance of xylem vessels is randomly distributed throughout the vessel network. We predicted that single vessel air injection (SVAI) vulnerability curves (VCs) would thus be affected by sample length. Longer stem samples were predicted to appear more resistant than shorter samples due to the sampled path including greater numbers of vessels. We evaluated the vessel network characteristics of grapevine (Vitis vinifera L.), English oak (Quercus robur L.) and black cottonwood (Populus trichocarpa Torr. & A. Gray), and constructed SVAI VCs for 5- and 20-cm-long segments. We also constructed VCs with a standard centrifuge method and used computer modelling to estimate the curve shift expected for pathways composed of different numbers of vessels. For all three species, the SVAI VCs for 5 cm segments rose exponentially and were more vulnerable than the 20 cm segments. The 5 cm curve shapes were exponential and were consistent with centrifuge VCs. Modelling data supported the observed SVAI VC shifts, which were related to path length and vessel network characteristics. These results suggest that exponential VCs represent the most realistic curve shape for individual vessel resistance distributions for these species. At the network level, the presence of some vessels with a higher resistance to cavitation may help avoid emboli spread during tissue dehydration.
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Affiliation(s)
- Martin D Venturas
- Department of Biology, California State University, Bakersfield, 9001 Stockdale Hwy, Bakersfield, CA 93311, USA
- Forest Genetics and Ecophysiology Research Group (GENFOR), School of Forest Engineering, Technical University of Madrid, 28040 Madrid, Spain
| | - F Daniela Rodriguez-Zaccaro
- Department of Biology, California State University, Bakersfield, 9001 Stockdale Hwy, Bakersfield, CA 93311, USA
| | - Marta I Percolla
- Department of Biology, California State University, Bakersfield, 9001 Stockdale Hwy, Bakersfield, CA 93311, USA
| | - Casparus J Crous
- Forestry and Agricultural Biotechnology Institute, University of Pretoria, Lynnwood Road & Roper Street, Hatfield, Pretoria 0002, South Africa
| | - Anna L Jacobsen
- Department of Biology, California State University, Bakersfield, 9001 Stockdale Hwy, Bakersfield, CA 93311, USA
| | - R Brandon Pratt
- Department of Biology, California State University, Bakersfield, 9001 Stockdale Hwy, Bakersfield, CA 93311, USA
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20
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Sack L, Ball MC, Brodersen C, Davis SD, Des Marais DL, Donovan LA, Givnish TJ, Hacke UG, Huxman T, Jansen S, Jacobsen AL, Johnson DM, Koch GW, Maurel C, McCulloh KA, McDowell NG, McElrone A, Meinzer FC, Melcher PJ, North G, Pellegrini M, Pockman WT, Pratt RB, Sala A, Santiago LS, Savage JA, Scoffoni C, Sevanto S, Sperry J, Tyerman SD, Way D, Holbrook NM. Plant hydraulics as a central hub integrating plant and ecosystem function: meeting report for 'Emerging Frontiers in Plant Hydraulics' (Washington, DC, May 2015). PLANT, CELL & ENVIRONMENT 2016; 39:2085-94. [PMID: 27037757 DOI: 10.1111/pce.12732] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 03/06/2016] [Indexed: 05/25/2023]
Abstract
Water plays a central role in plant biology and the efficiency of water transport throughout the plant affects both photosynthetic rate and growth, an influence that scales up deterministically to the productivity of terrestrial ecosystems. Moreover, hydraulic traits mediate the ways in which plants interact with their abiotic and biotic environment. At landscape to global scale, plant hydraulic traits are important in describing the function of ecological communities and ecosystems. Plant hydraulics is increasingly recognized as a central hub within a network by which plant biology is connected to palaeobiology, agronomy, climatology, forestry, community and ecosystem ecology and earth-system science. Such grand challenges as anticipating and mitigating the impacts of climate change, and improving the security and sustainability of our food supply rely on our fundamental knowledge of how water behaves in the cells, tissues, organs, bodies and diverse communities of plants. A workshop, 'Emerging Frontiers in Plant Hydraulics' supported by the National Science Foundation, was held in Washington DC, 2015 to promote open discussion of new ideas, controversies regarding measurements and analyses, and especially, the potential for expansion of up-scaled and down-scaled inter-disciplinary research, and the strengthening of connections between plant hydraulic research, allied fields and global modelling efforts.
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Affiliation(s)
- Lawren Sack
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
| | - Marilyn C Ball
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, 0200, Australia
| | - Craig Brodersen
- School of Forestry & Environmental Studies, Yale University, 195 Prospect Street, New Haven, CT, 06511, USA
| | - Stephen D Davis
- Natural Science Division, Pepperdine University, Malibu, CA, 90263, USA
| | - David L Des Marais
- Arnold Arboretum, Harvard University, Cambridge, MA, 02131, USA
- Department of Organismic and Evolutionary Biology, Harvard University, Boston, MA, 02138, USA
| | - Lisa A Donovan
- Department of Plant Biology, University of Georgia, Athens, GA, 30602, USA
| | - Thomas J Givnish
- Department of Botany, University of Wisconsin Madison, Madison, WI, 53706, USA
| | - Uwe G Hacke
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, T6G 2E3, Canada
| | - Travis Huxman
- Ecology and Evolutionary Biology & Center for Environmental Biology, University of California, Irvine, CA, 92697, USA
| | - Steven Jansen
- Ulm University, Institute of Systematic Botany and Ecology, Albert-Einstein-Allee 11, Ulm, 89081, Germany
| | - Anna L Jacobsen
- Department of Biology, California State University, Bakersfield, CA, 93311, USA
| | - Daniel M Johnson
- Department of Forest, Rangeland and Fire Sciences, University of Idaho, Moscow, ID, 83844, USA
| | - George W Koch
- Center for Ecosystem Science and Society, and Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Christophe Maurel
- Biochimie et Physiologie Moléculaire des Plantes, UMR 5004, INRA-CNRS-Sup Agro-Université de Montpellier, 2 Place Viala, Montpellier, F-34060, France
| | | | - Nate G McDowell
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Andrew McElrone
- Department of Viticulture and Enology, University of California, Davis, CA, 95616, USA
- USDA-Agricultural Research Service, Davis, CA, 95616, USA
| | - Frederick C Meinzer
- Pacific Northwest Research Station, USDA Forest Service, Corvallis, OR, 97331, USA
| | - Peter J Melcher
- Department of Biology, Ithaca College, Ithaca, NY, 14850, USA
| | - Gretchen North
- Department of Biology, Occidental College, Los Angeles, CA, 90041, USA
| | - Matteo Pellegrini
- Department of Molecular, Cell, and Developmental Biology, University of California Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
| | - William T Pockman
- Department of Biology, MSC03 2020, University of New Mexico, Albuquerque, NM, 87131, USA
| | - R Brandon Pratt
- Department of Biology, California State University, Bakersfield, CA, 93311, USA
| | - Anna Sala
- Division of Biological Sciences, University of Montana, Missoula, MT, 59812, USA
| | - Louis S Santiago
- Botany and Plant Sciences, University of California, Riverside, CA, 92521, USA
| | - Jessica A Savage
- Arnold Arboretum, Harvard University, Cambridge, MA, 02131, USA
- Department of Organismic and Evolutionary Biology, Harvard University, Boston, MA, 02138, USA
| | - Christine Scoffoni
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
| | - Sanna Sevanto
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - John Sperry
- Department of Biology, University of Utah, 257 South 1400 East, Salt Lake City, UT, 84112, USA
| | - Stephen D Tyerman
- ARC Centre of Excellence in Plant Energy Biology, School of Agriculture, Food and Wine, Waite Research Precinct, The University of Adelaide, PMB 1, Glen Osmond, South Australia, 5064, Australia
| | - Danielle Way
- Department of Biology, Western University, 1151 Richmond Street, London, Ontario, N6A 5B7, Canada
| | - N Michele Holbrook
- Department of Organismic and Evolutionary Biology, Harvard University, Boston, MA, 02138, USA
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