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Ingram S, Jansen S, Schenk HJ. Lipid-Coated Nanobubbles in Plants. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:nano13111776. [PMID: 37299679 DOI: 10.3390/nano13111776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 05/26/2023] [Accepted: 05/28/2023] [Indexed: 06/12/2023]
Abstract
One of the more surprising occurrences of bulk nanobubbles is in the sap inside the vascular transport system of flowering plants, the xylem. In plants, nanobubbles are subjected to negative pressure in the water and to large pressure fluctuations, sometimes encompassing pressure changes of several MPa over the course of a single day, as well as wide temperature fluctuations. Here, we review the evidence for nanobubbles in plants and for polar lipids that coat them, allowing nanobubbles to persist in this dynamic environment. The review addresses how the dynamic surface tension of polar lipid monolayers allows nanobubbles to avoid dissolution or unstable expansion under negative liquid pressure. In addition, we discuss theoretical considerations about the formation of lipid-coated nanobubbles in plants from gas-filled spaces in the xylem and the role of mesoporous fibrous pit membranes between xylem conduits in creating the bubbles, driven by the pressure gradient between the gas and liquid phase. We discuss the role of surface charges in preventing nanobubble coalescence, and conclude by addressing a number of open questions about nanobubbles in plants.
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Affiliation(s)
- Stephen Ingram
- Institute for Atmospheric and Earth System Research/Physics, University of Helsinki, 00560 Helsinki, Finland
| | - Steven Jansen
- Institute of Botany, Ulm University, 89081 Ulm, Germany
| | - H Jochen Schenk
- Department of Biological Science, California State University Fullerton, Fullerton, CA 92831-3599, USA
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2
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Guan X, Schenk HJ, Roth MR, Welti R, Werner J, Kaack L, Trabi CL, Jansen S. Nanoparticles are linked to polar lipids in xylem sap of temperate angiosperm species. TREE PHYSIOLOGY 2022; 42:2003-2019. [PMID: 35552762 DOI: 10.1093/treephys/tpac054] [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: 12/08/2021] [Accepted: 05/09/2022] [Indexed: 06/15/2023]
Abstract
In previous research, xylem sap of angiosperms has been found to include low concentrations of nanoparticles and polar lipids. A major goal of this study was to test predictions arising from the hypothesis that the nanoparticles consist largely of polar lipids from the original cell content of vessel elements. These predictions included that polar lipid and nanoparticle concentrations would be correlated, that they both do not pass through pit membranes and that they do not vary seasonally because they originate from living vessel element cells. We collected xylem sap of six temperate angiosperm species over the whole year to consider seasonal variation. Concentrations of nanoparticles and lipids in xylem sap and contamination control samples were measured with a NanoSight device and mass spectrometry. We found that the concentration of nanoparticles and polar lipids was (i) diluted when an increasing amount of sap was extracted, (ii) significantly correlated to each other for three species, (iii) affected by vessel anatomy, (iv) very low and largely different in chemical composition from contamination controls and (v) hardly variable among seasons. Moreover, there was a minor freezing-thawing effect with respect to nanoparticle amount and size. Xylem sap lipids included polar galactolipids and phospholipids in all species and neutral triacylglycerols in two species. These findings support the predictions and, by implication, the underlying hypothesis that nanoparticles in xylem sap consist of polar lipids from the original cell content of living vessel element cells. Further research is needed to examine the formation and stability of nanoparticles concerning lipid composition and multiphase interactions among gas, liquid and solid phases in xylem conduits of living plants.
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Affiliation(s)
- Xinyi Guan
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - H Jochen Schenk
- Department of Biological Science, California State University Fullerton, 800 N. State College Boulevard, Fullerton, CA 92831, USA
| | - Mary R Roth
- Kansas Lipidomics Research Center, Division of Biology, Kansas State University, Manhattan, KS 66506, USA
| | - Ruth Welti
- Kansas Lipidomics Research Center, Division of Biology, Kansas State University, Manhattan, KS 66506, USA
| | - Julia Werner
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Lucian Kaack
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Christophe L Trabi
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
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3
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Perré P, Nguyen DM, Almeida G. A macroscopic Washburn approach of liquid imbibition in wood derived from X-ray tomography observations. Sci Rep 2022; 12:1750. [PMID: 35110606 PMCID: PMC8811000 DOI: 10.1038/s41598-022-05508-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 11/23/2021] [Indexed: 01/25/2023] Open
Abstract
Imbibition of water and silicone oil in poplar and spruce is investigated at the anatomical level by X-ray tomography observations and at the macroscopic level by imbibition kinetics. Imbibition mechanisms depend on both liquid and species. In poplar, oil penetrates vessels with a small contact angle, consistent with the value measured on solid wood (ca. \documentclass[12pt]{minimal}
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\begin{document}$$20^{\circ }$$\end{document}20∘). Surprisingly, no direct penetration of water was observed in vessels. The large contact angle for water blocks the capillary rise at the scars between vessel cells. In spruce, oil and water penetrate primarily in latewood, where bordered pits remain open. Subsequently, water slowly invades the rest of the growth ring, while transversal migration is quasi-absent for oil. These 3D observations were quantified to feed a simple imbibition model that satisfactorily simulates macroscopic imbibition kinetics. A 1D approach is sufficient for oil imbibition while a 2D approach is required for water, revealing dual scale effects.
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Affiliation(s)
- Patrick Perré
- CentraleSupélec, Laboratoire de Génie des Procédés et Matériaux, SFR Condorcet FR CNRS 3417, Centre Européen de Biotechnologie et de Bioéconomie (CEBB), Université Paris-Saclay, 3 Rue des Rouges Terres, 51110, Pomacle, France.
| | - Dang Mao Nguyen
- CentraleSupélec, Laboratoire de Génie des Procédés et Matériaux, SFR Condorcet FR CNRS 3417, Centre Européen de Biotechnologie et de Bioéconomie (CEBB), Université Paris-Saclay, 3 Rue des Rouges Terres, 51110, Pomacle, France
| | - Giana Almeida
- INRAE, AgroParisTech, UMR SayFood, Université Paris-Saclay, 91300, Massy, France
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4
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Guan X, Pereira L, McAdam SAM, Cao KF, Jansen S. No gas source, no problem: Proximity to pre-existing embolism and segmentation affect embolism spreading in angiosperm xylem by gas diffusion. PLANT, CELL & ENVIRONMENT 2021; 44:1329-1345. [PMID: 33529382 DOI: 10.1111/pce.14016] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 01/16/2021] [Accepted: 01/17/2021] [Indexed: 05/12/2023]
Abstract
Embolism spreading in dehydrating angiosperm xylem is driven by gas movement between embolized and sap-filled conduits. Here we examine how the proximity to pre-existing embolism and hydraulic segmentation affect embolism propagation. Based on the optical method, we compare xylem embolism resistance between detached leaves and leaves attached to branches, and between intact leaves and leaves with cut minor veins, for six species. Embolism resistance of detached leaves was significantly lower than that of leaves attached to stems, except for two species, with all vessels ending in their petioles. Cutting of minor veins showed limited embolism spreading in minor veins near the cuts prior to major veins. Moreover, despite strong agreement in the overall embolism resistance of detached leaves between the optical and pneumatic method, minor differences were observed during early stages of embolism formation. We conclude that embolism resistance may represent a relative trait due to an open-xylem artefact, with embolism spreading possibly affected by the proximity and connectivity to pre-existing embolism as a gas source, while hydraulic segmentation prevents such artefact. Since embolism formation may not rely on a certain pressure difference threshold between functional and embolized conduits, we speculate that embolism is facilitated by pressure-driven gas diffusion across pit membranes.
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Affiliation(s)
- Xinyi Guan
- Institute of Systematic Botany and Ecology, Ulm University, Ulm, Germany
| | - Luciano Pereira
- Institute of Systematic Botany and Ecology, Ulm University, Ulm, Germany
- Laboratory of Plant Physiology "Coaracy M. Franco", Center R&D in Ecophysiology and Biophysics, Agronomic Institute (IAC), Campinas, Brazil
- Laboratory of Crop Physiology, Department of Plant Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Scott A M McAdam
- Purdue Center for Plant Biology, Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana, USA
| | - Kun-Fang Cao
- Plant Ecophysiology and Evolution Group, State Key Laboratory for Conservation and Utilisation of Subtropical Agro-Bioresources, Guangxi University, Nanning, China
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, China
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Ulm, Germany
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5
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Schenk HJ, Michaud JM, Mocko K, Espino S, Melendres T, Roth MR, Welti R, Kaack L, Jansen S. Lipids in xylem sap of woody plants across the angiosperm phylogeny. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 105:1477-1494. [PMID: 33295003 DOI: 10.1111/tpj.15125] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 11/13/2020] [Indexed: 06/12/2023]
Abstract
Lipids have been observed attached to lumen-facing surfaces of mature xylem conduits of several plant species, but there has been little research on their functions or effects on water transport, and only one lipidomic study of the xylem apoplast. Therefore, we conducted lipidomic analyses of xylem sap from woody stems of seven plants representing six major angiosperm clades, including basal magnoliids, monocots and eudicots, to characterize and quantify phospholipids, galactolipids and sulfolipids in sap using mass spectrometry. Locations of lipids in vessels of Laurus nobilis were imaged using transmission electron microscopy and confocal microscopy. Xylem sap contained the galactolipids di- and monogalactosyldiacylglycerol, as well as all common plant phospholipids, but only traces of sulfolipids, with total lipid concentrations in extracted sap ranging from 0.18 to 0.63 nmol ml-1 across all seven species. Contamination of extracted sap from lipids in cut living cells was found to be negligible. Lipid composition of sap was compared with wood in two species and was largely similar, suggesting that sap lipids, including galactolipids, originate from cell content of living vessels. Seasonal changes in lipid composition of sap were observed for one species. Lipid layers coated all lumen-facing vessel surfaces of L. nobilis, and lipids were highly concentrated in inter-vessel pits. The findings suggest that apoplastic, amphiphilic xylem lipids are a universal feature of angiosperms. The findings require a reinterpretation of the cohesion-tension theory of water transport to account for the effects of apoplastic lipids on dynamic surface tension and hydraulic conductance in xylem.
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Affiliation(s)
- H Jochen Schenk
- Department of Biological Science, California State University Fullerton, 800 N. State College Boulevard, Fullerton, CA, 92831, USA
| | - Joseph M Michaud
- Department of Biological Science, California State University Fullerton, 800 N. State College Boulevard, Fullerton, CA, 92831, USA
| | - Kerri Mocko
- Department of Biological Science, California State University Fullerton, 800 N. State College Boulevard, Fullerton, CA, 92831, USA
| | - Susana Espino
- Department of Biological Science, California State University Fullerton, 800 N. State College Boulevard, Fullerton, CA, 92831, USA
| | - Tatiana Melendres
- Department of Biological Science, California State University Fullerton, 800 N. State College Boulevard, Fullerton, CA, 92831, USA
| | - Mary R Roth
- Kansas Lipidomics Research Center, Division of Biology, Kansas State University, Manhattan, KS, 66506, USA
| | - Ruth Welti
- Kansas Lipidomics Research Center, Division of Biology, Kansas State University, Manhattan, KS, 66506, USA
| | - Lucian Kaack
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, Ulm, D-89081, Germany
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, Ulm, D-89081, Germany
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6
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Jansen S, Guan X, Kaack L, Trabi C, Miranda M, Ribeiro R, Pereira L. The Pneumatron estimates xylem embolism resistance in angiosperms based on gas diffusion kinetics: a mini-review. ACTA ACUST UNITED AC 2020. [DOI: 10.17660/actahortic.2020.1300.25] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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7
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Cavitation in lipid bilayers poses strict negative pressure stability limit in biological liquids. Proc Natl Acad Sci U S A 2020; 117:10733-10739. [PMID: 32358185 DOI: 10.1073/pnas.1917195117] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Biological and technological processes that involve liquids under negative pressure are vulnerable to the formation of cavities. Maximal negative pressures found in plants are around -100 bar, even though cavitation in pure bulk water only occurs at much more negative pressures on the relevant timescales. Here, we investigate the influence of small solutes and lipid bilayers, both constituents of all biological liquids, on the formation of cavities under negative pressures. By combining molecular dynamics simulations with kinetic modeling, we quantify cavitation rates on biologically relevant length scales and timescales. We find that lipid bilayers, in contrast to small solutes, increase the rate of cavitation, which remains unproblematically low at the pressures found in most plants. Only when the negative pressures approach -100 bar does cavitation occur on biologically relevant timescales. Our results suggest that bilayer-based cavitation is what generally limits the magnitude of negative pressures in liquids that contain lipid bilayers.
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8
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Yang J, M Michaud J, Jansen S, Schenk HJ, Zuo YY. Dynamic surface tension of xylem sap lipids. TREE PHYSIOLOGY 2020; 40:433-444. [PMID: 32031666 DOI: 10.1093/treephys/tpaa006] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 11/01/2019] [Accepted: 01/13/2020] [Indexed: 06/10/2023]
Abstract
The surface tension of xylem sap has been traditionally assumed to be close to that of the pure water because decreasing surface tension is thought to increase vulnerability to air seeding and embolism. However, xylem sap contains insoluble lipid-based surfactants, which also coat vessel and pit membrane surfaces, where gas bubbles can enter xylem under negative pressure in the process known as air seeding. Because of the insolubility of amphiphilic lipids, the surface tension influencing air seeding in pit pores is not the equilibrium surface tension of extracted bulk sap but the local surface tension at gas-liquid interfaces, which depends dynamically on the local concentration of lipids per surface area. To estimate the dynamic surface tension in lipid layers that line surfaces in the xylem apoplast, we studied the time-dependent and surface area-regulated surface tensions of apoplastic lipids extracted from xylem sap of four woody angiosperm plants using constrained drop surfactometry. Xylem lipids were found to demonstrate potent surface activity, with surface tensions reaching an equilibrium at ~25 mN m-1 and varying between a minimum of 19 mN m-1 and a maximum of 68 mN m-1 when changing the surface area between 50 and 160% around the equilibrium surface area. It is concluded that xylem lipid films in natural conditions most likely range from nonequilibrium metastable conditions of a supersaturated compression state to an undersaturated expansion state, depending on the local surface areas of gas-liquid interfaces. Together with findings that maximum pore constrictions in angiosperm pit membranes are much smaller than previously assumed, low dynamic surface tension in xylem turns out to be entirely compatible with the cohesion-tension and air-seeding theories, as well as with the existence of lipid-coated nanobubbles in xylem sap, and with the range of vulnerabilities to embolism observed in plants.
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Affiliation(s)
- Jinlong Yang
- Department of Mechanical Engineering, University of Hawaii at Manoa, 2540 Dole Street, Holmes Hall 302, Honolulu, HI 96822, USA
| | - Joseph M Michaud
- Department of Biological Science, California State University, 800 N. State College Blvd., Fullerton, CA 92831, USA
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, Ulm D-89081, Germany
| | - H Jochen Schenk
- Department of Biological Science, California State University, 800 N. State College Blvd., Fullerton, CA 92831, USA
| | - Yi Y Zuo
- Department of Mechanical Engineering, University of Hawaii at Manoa, 2540 Dole Street, Holmes Hall 302, Honolulu, HI 96822, USA
- Department of Pediatrics, John A. Burns School of Medicine, University of Hawaii, 1319 Punahou Street, Honolulu, HI 96826, USA
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9
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Li S, Wang J, Yin Y, Li X, Deng L, Jiang X, Chen Z, Li Y. Investigating Effects of Bordered Pit Membrane Morphology and Properties on Plant Xylem Hydraulic Functions-A Case Study from 3D Reconstruction and Microflow Modelling of Pit Membranes in Angiosperm Xylem. PLANTS (BASEL, SWITZERLAND) 2020; 9:E231. [PMID: 32054100 PMCID: PMC7076482 DOI: 10.3390/plants9020231] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 01/18/2020] [Accepted: 02/08/2020] [Indexed: 01/12/2023]
Abstract
Pit membranes in between neighboring conduits of xylem play a crucial role in plant water transport. In this review, the morphological characteristics, chemical composition and mechanical properties of bordered pit membranes were summarized and linked with their functional roles in xylem hydraulics. The trade-off between xylem hydraulic efficiency and safety was closely related with morphology and properties of pit membranes, and xylem embolism resistance was also determined by the pit membrane morphology and properties. Besides, to further investigate the effects of bordered pit membranes morphology and properties on plant xylem hydraulic functions, here we modelled three-dimensional structure of bordered pit membranes by applying a deposition technique. Based on reconstructed 3D pit membrane structures, a virtual fibril network was generated to model the microflow pattern across inter-vessel pit membranes. Moreover, the mechanical behavior of intervessel pit membranes was estimated from a single microfibril's mechanical property. Pit membranes morphology varied among different angiosperm and gymnosperm species. Our modelling work suggested that larger pores of pit membranes do not necessarily contribute to major flow rate across pit membranes; instead, the obstructed degree of flow pathway across the pit membranes plays a more important role. Our work provides useful information for studying the mechanism of microfluid flow transport across pit membranes and also sheds light on investigating the response of pit membranes both at normal and stressed conditions, thus improving our understanding on functional roles of pit membranes in xylem hydraulic function. Further work could be done to study the morphological and mechanical response of bordered pit membranes under different dehydrated conditions, as well as the related microflow behavior, based on our constructed model.
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Affiliation(s)
- Shan Li
- Department of Wood Anatomy and Utilization, Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, China; (S.L.); (J.W.); (Y.Y.); (L.D.); (X.J.)
- Wood Collections (WOODPEDIA), Chinese Academy of Forestry, Beijing 100091, China
| | - Jie Wang
- Department of Wood Anatomy and Utilization, Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, China; (S.L.); (J.W.); (Y.Y.); (L.D.); (X.J.)
- Wood Collections (WOODPEDIA), Chinese Academy of Forestry, Beijing 100091, China
| | - Yafang Yin
- Department of Wood Anatomy and Utilization, Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, China; (S.L.); (J.W.); (Y.Y.); (L.D.); (X.J.)
- Wood Collections (WOODPEDIA), Chinese Academy of Forestry, Beijing 100091, China
| | - Xin Li
- College of Forestry, Beijing Forestry University, Beijing 100083, China;
| | - Liping Deng
- Department of Wood Anatomy and Utilization, Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, China; (S.L.); (J.W.); (Y.Y.); (L.D.); (X.J.)
- International Center for Bamboo and Rattan, Beijing 100102, China
| | - Xiaomei Jiang
- Department of Wood Anatomy and Utilization, Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, China; (S.L.); (J.W.); (Y.Y.); (L.D.); (X.J.)
- Wood Collections (WOODPEDIA), Chinese Academy of Forestry, Beijing 100091, China
| | - Zhicheng Chen
- Institute of New Forestry Technology, Chinese Academy of Forestry, Beijing 100083, China;
| | - Yujun Li
- School of Mechanical Engineering, Northwestern Polytechnical University, Xi’an 710072, China
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10
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Zhang Y, Carmesin C, Kaack L, Klepsch MM, Kotowska M, Matei T, Schenk HJ, Weber M, Walther P, Schmidt V, Jansen S. High porosity with tiny pore constrictions and unbending pathways characterize the 3D structure of intervessel pit membranes in angiosperm xylem. PLANT, CELL & ENVIRONMENT 2020; 43:116-130. [PMID: 31595539 DOI: 10.1111/pce.13654] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 09/10/2019] [Accepted: 09/10/2019] [Indexed: 05/29/2023]
Abstract
Pit membranes between xylem vessels play a major role in angiosperm water transport. Yet, their three-dimensional (3D) structure as fibrous porous media remains unknown, largely due to technical challenges and sample preparation artefacts. Here, we applied a modelling approach based on thickness measurements of fresh and fully shrunken pit membranes of seven species. Pore constrictions were also investigated visually by perfusing fresh material with colloidal gold particles of known sizes. Based on a shrinkage model, fresh pit membranes showed tiny pore constrictions of ca. 20 nm, but a very high porosity (i.e. pore volume fraction) of on average 0.81. Perfusion experiments showed similar pore constrictions in fresh samples, well below 50 nm based on transmission electron microscopy. Drying caused a 50% shrinkage of pit membranes, resulting in much smaller pore constrictions. These findings suggest that pit membranes represent a mesoporous medium, with the pore space characterized by multiple constrictions. Constrictions are much smaller than previously assumed, but the pore volume is large and highly interconnected. Pores do not form highly tortuous, bent, or zigzagging pathways. These insights provide a novel view on pit membranes, which is essential to develop a mechanistic, 3D understanding of air-seeding through this porous medium.
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Affiliation(s)
- Ya Zhang
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
- College of Life Sciences, Anhui Normal University, Beijingdong Road 1, 241000, Wuhu, Anhui, China
| | - Cora Carmesin
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Lucian Kaack
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Matthias M Klepsch
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Martyna Kotowska
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
- Albrecht-von-Haller Institute for Plant Sciences, University of Göttingen, Untere Karspüle 2, 37073, Göttingen, Germany
| | - Tabea Matei
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - H Jochen Schenk
- Department of Biological Science, California State University Fullerton, 800 N. State College Blvd, CA, 92831-3599, Fullerton, USA
| | - Matthias Weber
- Institute of Stochastics, Ulm University, Helmholtzstraße 18, 89069, Ulm, Germany
| | - Paul Walther
- Central Facility for Electron Microscopy, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Volker Schmidt
- Institute of Stochastics, Ulm University, Helmholtzstraße 18, 89069, Ulm, Germany
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
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11
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Pits with aspiration explain life expectancy of a conifer species. Proc Natl Acad Sci U S A 2019; 116:14794-14796. [PMID: 31289227 DOI: 10.1073/pnas.1909866116] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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12
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Yin P, Meng F, Liu Q, An R, Cai J, Du G. A comparison of two centrifuge techniques for constructing vulnerability curves: insight into the 'open-vessel' artifact. PHYSIOLOGIA PLANTARUM 2019; 165:701-710. [PMID: 29602179 DOI: 10.1111/ppl.12738] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 03/16/2018] [Accepted: 03/25/2018] [Indexed: 06/08/2023]
Abstract
A vulnerability curve (VC) describes the extent of xylem cavitation resistance. Centrifuges have been used to generate VCs for decades via static- and flow-centrifuge methods. Recently, the validity of the centrifuge techniques has been questioned. Researchers have hypothesized that the centrifuge techniques might yield unreliable VCs due to the open-vessel artifact. However, other researchers reject this hypothesis. The focus of the dispute is centered on whether exponential VCs are more reliable when the static-centrifuge method is used rather than the flow-centrifuge method. To further test the reliability of the centrifuge technique, two centrifuges were manufactured to simulate the static- and flow-centrifuge methods. VCs of three species with open vessels of known lengths were constructed using the two centrifuges. The results showed that both centrifuge techniques produced invalid VCs for Robinia because the water flow through stems under mild tension in centrifuges led to an increasing loss of water conductivity. In addition, the injection of water in the flow-centrifuge exacerbated the loss of water conductivity. However, both centrifuge techniques yielded reliable VCs for Prunus, regardless of the presence of open vessels in the tested samples. We conclude that centrifuge techniques can be used in species with open vessels only when the centrifuge produces a VC that matches the bench-dehydration VC.
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Affiliation(s)
- Pengxian Yin
- College of Forestry, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Feng Meng
- College of Science, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Qing Liu
- College of Forestry, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Rui An
- College of Science, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Jing Cai
- College of Forestry, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Guangyuan Du
- College of Science, Northwest A&F University, Yangling, Shaanxi 712100, China
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13
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Beikircher B, Losso A, Gemassmer M, Jansen S, Mayr S. Does fertilization explain the extraordinary hydraulic behaviour of apple trees? JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:1915-1925. [PMID: 30793193 PMCID: PMC6436149 DOI: 10.1093/jxb/erz070] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 02/07/2019] [Indexed: 05/13/2023]
Abstract
Fertilization of woody plants plays a central role in agriculture and forestry, but little is known about how plant water relations are thereby affected. Here we investigated the impact of fertilization on tree hydraulics, and xylem and pit anatomy in the high-yield apple cultivars Golden and Red Delicious. In fertilized trees of Golden Delicious, specific hydraulic conductivity of branch xylem, hydraulic conductance of the root system, and maximum stomatal conductance increased considerably. In Red Delicious, differences between fertilized and control trees were less pronounced. In both cultivars, xylem embolism resistance of fertilized trees was significantly lower and stomatal closure occurred at lower water potentials. Furthermore, water potential at turgor loss point and osmotic potential at full saturation were higher and cell wall elasticity was lower in fertilized plants, suggesting reduced drought tolerance of leaves. Anatomical differences were observed regarding conduit diameters, cell wall reinforcement, pit membrane thickness, pit chamber depth, and stomatal pore length, with more pronounced differences in Golden Delicious. The findings reveal altered hydraulic behaviour in both apple cultivars upon fertilization. The increased vulnerability to hydraulic failure might pose a considerable risk for apple productivity under a changing climate, which should be considered for future cultivation and management practices.
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Affiliation(s)
- Barbara Beikircher
- University of Innsbruck, Institute of Botany, Sternwartestrasse, Innsbruck, Austria
| | - Adriano Losso
- University of Innsbruck, Institute of Botany, Sternwartestrasse, Innsbruck, Austria
| | - Marilena Gemassmer
- University of Innsbruck, Institute of Botany, Sternwartestrasse, Innsbruck, Austria
| | - Steven Jansen
- Ulm University, Institute of Systematic Botany and Ecology, Albert-Einstein-Allee, Ulm, Germany
| | - Stefan Mayr
- University of Innsbruck, Institute of Botany, Sternwartestrasse, Innsbruck, Austria
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14
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Mrad A, Domec JC, Huang CW, Lens F, Katul G. A network model links wood anatomy to xylem tissue hydraulic behaviour and vulnerability to cavitation. PLANT, CELL & ENVIRONMENT 2018; 41:2718-2730. [PMID: 30071137 DOI: 10.1111/pce.13415] [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: 05/30/2018] [Revised: 07/13/2018] [Accepted: 07/25/2018] [Indexed: 05/06/2023]
Abstract
Plant xylem response to drought is routinely represented by a vulnerability curve (VC). Despite the significance of VCs, the connection between anatomy and tissue-level hydraulic response to drought remains a subject of inquiry. We present a numerical model of water flow in flowering plant xylem that combines current knowledge on diffuse-porous anatomy and embolism spread to explore this connection. The model produces xylem networks and uses different parameterizations of intervessel connection vulnerability to embolism spread: the Young-Laplace equation and pit membrane stretching. Its purpose is upscaling processes occurring on the microscopic length scales, such as embolism propagation through pit membranes, to obtain tissue-scale hydraulics. The terminal branch VC of Acer glabrum was successfully reproduced relying only on real observations of xylem tissue anatomy. A sensitivity analysis shows that hydraulic performance and VC shape and location along the water tension axis are heavily dependent on anatomy. The main result is that the linkage between pit-scale and vessel-scale anatomical characters, along with xylem network topology, affects VCs significantly. This work underscores the importance of stepping up research related to the three-dimensional network structure of xylem tissues. The proposed model's versatility makes it an important tool to explore similar future questions.
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Affiliation(s)
- Assaad Mrad
- Nicholas School of the Environment, Duke University, Durham, NC, 27708, USA
| | - Jean-Christophe Domec
- Nicholas School of the Environment, Duke University, Durham, NC, 27708, USA
- Bordeaux Sciences Agro, UMR 1391 INRA-ISPA, 33175, Gradignan Cedex, France
| | - Cheng-Wei Huang
- Department of Biology, University of New Mexico, Albuquerque, NM, 87131-0001
| | - Frederic Lens
- Naturalis Biodiversity Center, Leiden University, P.O. Box 9517, 2300 RA Leiden, The Netherlands
| | - Gabriel Katul
- Nicholas School of the Environment, Duke University, Durham, NC, 27708, USA
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15
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Klepsch M, Zhang Y, Kotowska MM, Lamarque LJ, Nolf M, Schuldt B, Torres-Ruiz JM, Qin DW, Choat B, Delzon S, Scoffoni C, Cao KF, Jansen S. Is xylem of angiosperm leaves less resistant to embolism than branches? Insights from microCT, hydraulics, and anatomy. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:5611-5623. [PMID: 30184113 PMCID: PMC6255699 DOI: 10.1093/jxb/ery321] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 08/28/2018] [Indexed: 05/23/2023]
Abstract
According to the hydraulic vulnerability segmentation hypothesis, leaves are more vulnerable to decline of hydraulic conductivity than branches, but whether stem xylem is more embolism resistant than leaves remains unclear. Drought-induced embolism resistance of leaf xylem was investigated based on X-ray microcomputed tomography (microCT) for Betula pendula, Laurus nobilis, and Liriodendron tulipifera, excluding outside-xylem, and compared with hydraulic vulnerability curves for branch xylem. Moreover, bordered pit characters related to embolism resistance were investigated for both organs. Theoretical P50 values (i.e. the xylem pressure corresponding to 50% loss of hydraulic conductance) of leaves were generally within the same range as hydraulic P50 values of branches. P50 values of leaves were similar to branches for L. tulipifera (-2.01 versus -2.10 MPa, respectively), more negative for B. pendula (-2.87 versus -1.80 MPa), and less negative for L. nobilis (-6.4 versus -9.2 MPa). Despite more narrow conduits in leaves than branches, mean interconduit pit membrane thickness was similar in both organs, but significantly higher in leaves of B. pendula than in branches. This case study indicates that xylem shows a largely similar embolism resistance across leaves and branches, although differences both within and across organs may occur, suggesting interspecific variation with regard to the hydraulic vulnerability segmentation hypothesis.
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Affiliation(s)
- Matthias Klepsch
- Institute of Systematic Botany and Ecology, Albert-Einstein-Allee 11, Ulm University, Ulm, Germany
| | - Ya Zhang
- Institute of Systematic Botany and Ecology, Albert-Einstein-Allee 11, Ulm University, Ulm, Germany
| | - Martyna M Kotowska
- Department of Biological Sciences Faculty of Science, Macquarie University, NSW, Australia
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Untere Karspüle, Göttingen, Germany
| | - Laurent J Lamarque
- BIOGECO, INRA, University of Bordeaux, Pessac, France
- EGFV, INRA, University of Bordeaux, Villenave d’Ornon, France
| | - Markus Nolf
- Hawkesbury Institute for the Environment, University of Western Sydney, Richmond, New South Wales, Australia
| | - Bernhard Schuldt
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Untere Karspüle, Göttingen, Germany
| | - José M Torres-Ruiz
- BIOGECO, INRA, University of Bordeaux, Pessac, France
- Université Clermont-Auvergne, INRA, PIAF, Clermont-Ferrand, France
| | - De-Wen Qin
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Daxuedonglu, Nanning, Guangxi, PR China
| | - Brendan Choat
- Hawkesbury Institute for the Environment, University of Western Sydney, Richmond, New South Wales, Australia
| | | | - Christine Scoffoni
- Department of Biological Sciences, California State University, Los Angeles, State University Drive, Los Angeles, CA, USA
| | - Kun-Fang Cao
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Daxuedonglu, Nanning, Guangxi, PR China
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Albert-Einstein-Allee 11, Ulm University, Ulm, Germany
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16
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Jansen S, Klepsch M, Li S, Kotowska M, Schiele S, Zhang Y, Schenk H. Challenges in understanding air-seeding in angiosperm xylem. ACTA ACUST UNITED AC 2018. [DOI: 10.17660/actahortic.2018.1222.3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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17
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Schenk HJ, Espino S, Rich-Cavazos SM, Jansen S. From the sap's perspective: The nature of vessel surfaces in angiosperm xylem. AMERICAN JOURNAL OF BOTANY 2018; 105:172-185. [PMID: 29578294 DOI: 10.1002/ajb2.1034] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Accepted: 12/14/2017] [Indexed: 06/08/2023]
Abstract
PREMISE OF THE STUDY Xylem sap in angiosperms moves under negative pressure in conduits and cell wall pores that are nanometers to micrometers in diameter, so sap is always very close to surfaces. Surfaces matter for water transport because hydrophobic ones favor nucleation of bubbles, and surface chemistry can have strong effects on flow. Vessel walls contain cellulose, hemicellulose, lignin, pectins, proteins, and possibly lipids, but what is the nature of the inner, lumen-facing surface that is in contact with sap? METHODS Vessel lumen surfaces of five angiosperms from different lineages were examined via transmission electron microscopy and confocal and fluorescence microscopy, using fluorophores and autofluorescence to detect cell wall components. Elemental composition was studied by energy-dispersive X-ray spectroscopy, and treatments with phospholipase C (PLC) were used to test for phospholipids. KEY RESULTS Vessel surfaces consisted mainly of lignin, with strong cellulose signals confined to pit membranes. Proteins were found mainly in inter-vessel pits and pectins only on outer rims of pit membranes and in vessel-parenchyma pits. Continuous layers of lipids were detected on most vessel surfaces and on most pit membranes and were shown by PLC treatment to consist at least partly of phospholipids. CONCLUSIONS Vessel surfaces appear to be wettable because lignin is not strongly hydrophobic and a coating with amphiphilic lipids would render any surface hydrophilic. New questions arise about these lipids and their possible origins from living xylem cells, especially about their effects on surface tension, surface bubble nucleation, and pit membrane function.
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Affiliation(s)
- H Jochen Schenk
- Department of Biological Science, California State University Fullerton, Fullerton, CA 92831, USA
| | - Susana Espino
- Department of Biological Science, California State University Fullerton, Fullerton, CA 92831, USA
| | - Sarah M Rich-Cavazos
- Department of Biological Science, California State University Fullerton, Fullerton, CA 92831, USA
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, D-89081, Ulm, Germany
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18
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Jochen Schenk H. Wood: Biology of a living tissue. AMERICAN JOURNAL OF BOTANY 2018; 105:139-141. [PMID: 29569710 DOI: 10.1002/ajb2.1039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 02/21/2018] [Indexed: 06/08/2023]
Affiliation(s)
- H Jochen Schenk
- Department of Biological Science, California State University Fullerton, 800 N. State College Boulevard, Fullerton, CA, 92831, USA
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19
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Morris H, Plavcová L, Gorai M, Klepsch MM, Kotowska M, Jochen Schenk H, Jansen S. Vessel-associated cells in angiosperm xylem: Highly specialized living cells at the symplast-apoplast boundary. AMERICAN JOURNAL OF BOTANY 2018; 105:151-160. [PMID: 29578292 DOI: 10.1002/ajb2.1030] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 11/13/2017] [Indexed: 05/13/2023]
Abstract
BACKGROUND Vessel-associated cells (VACs) are highly specialized, living parenchyma cells that are in direct contact with water-conducting, dead vessels. The contact may be sparse or in large tight groups of parenchyma that completely surrounds vessels. VACs differ from vessel distant parenchyma in physiology, anatomy, and function and have half-bordered pits at the vessel-parenchyma juncture. The distinct anatomy of VACs is related to the exchange of substances to and from the water-transport system, with the cells long thought to be involved in water transport in woody angiosperms, but where direct experimental evidence is lacking. SCOPE This review focuses on our current knowledge of VACs regarding anatomy and function, including hydraulic capacitance, storage of nonstructural carbohydrates, symplastic and apoplastic interactions, defense against pathogens and frost, osmoregulation, and the novel hypothesis of surfactant production. Based on microscopy, we visually represent how VACs vary in dimensions and general appearance between species, with special attention to the protoplast, amorphous layer, and the vessel-parenchyma pit membrane. CONCLUSIONS An understanding of the relationship between VACs and vessels is crucial to tackling questions related to how water is transported over long distances in xylem, as well as defense against pathogens. New avenues of research show how parenchyma-vessel contact is related to vessel diameter and a new hypothesis may explain how surfactants arising from VAC can allow water to travel under negative pressure. We also reinforce the message of connectivity between VAC and other cells between xylem and phloem.
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Affiliation(s)
- Hugh Morris
- Ulm University, Institute of Systematic Botany and Ecology, Albert-Einstein-Allee 11, 89081, Ulm, Germany
- Laboratory for Applied Wood Materials, Empa-Swiss Federal Laboratories for Materials Testing and Research, St. Gallen, Switzerland
| | - Lenka Plavcová
- University of Hradec Králové, Department of Biology, Faculty of Science, Rokitanského 62, 500 03, Hradec Králové, Czech Republic
| | - Mustapha Gorai
- University of Gabes, Higher Institute of Applied Biology of Medenine, Medenine, 4119, Tunisia
| | - Matthias M Klepsch
- Ulm University, Institute of Systematic Botany and Ecology, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Martyna Kotowska
- Ulm University, Institute of Systematic Botany and Ecology, Albert-Einstein-Allee 11, 89081, Ulm, Germany
- Macquarie University, Department of Biological Sciences, North Ryde, NSW, 2109, Australia
| | - H Jochen Schenk
- California State University Fullerton, Department of Biological Science, 800 N. State College Blvd., Fullerton, CA, 92831-3599, USA
| | - Steven Jansen
- Ulm University, Institute of Systematic Botany and Ecology, Albert-Einstein-Allee 11, 89081, Ulm, Germany
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20
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Morris H, Gillingham MAF, Plavcová L, Gleason SM, Olson ME, Coomes DA, Fichtler E, Klepsch MM, Martínez-Cabrera HI, McGlinn DJ, Wheeler EA, Zheng J, Ziemińska K, Jansen S. Vessel diameter is related to amount and spatial arrangement of axial parenchyma in woody angiosperms. PLANT, CELL & ENVIRONMENT 2018; 41:245-260. [PMID: 29047119 DOI: 10.1111/pce.13091] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 09/22/2017] [Accepted: 09/28/2017] [Indexed: 05/13/2023]
Abstract
Parenchyma represents a critically important living tissue in the sapwood of the secondary xylem of woody angiosperms. Considering various interactions between parenchyma and water transporting vessels, we hypothesize a structure-function relationship between both cell types. Through a generalized additive mixed model approach based on 2,332 woody angiosperm species derived from the literature, we explored the relationship between the proportion and spatial distribution of ray and axial parenchyma and vessel size, while controlling for maximum plant height and a range of climatic factors. When factoring in maximum plant height, we found that with increasing mean annual temperatures, mean vessel diameter showed a positive correlation with axial parenchyma proportion and arrangement, but not for ray parenchyma. Species with a high axial parenchyma tissue fraction tend to have wide vessels, with most of the parenchyma packed around vessels, whereas species with small diameter vessels show a reduced amount of axial parenchyma that is not directly connected to vessels. This finding provides evidence for independent functions of axial parenchyma and ray parenchyma in large vesselled species and further supports a strong role for axial parenchyma in long-distance xylem water transport.
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Affiliation(s)
- Hugh Morris
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
- Laboratory for Applied Wood Materials, Empa-Swiss Federal Laboratories for Materials Testing and Research, St. Gallen, 9014, Switzerland
| | - Mark A F Gillingham
- Institute of Evolutionary Ecology and Conservation Genomics, Ulm University, Albert-Einstein-Allee 11, D-89069, Ulm, Germany
| | - Lenka Plavcová
- Department of Biology, Faculty of Science, University of Hradec Králové, Rokitanského 62, 500 03, Hradec Králové, Czech Republic
| | - Sean M Gleason
- USDA-ARS Water Management and Systems Research Unit, Fort Collins, CO, 80526, USA
| | - Mark E Olson
- Instituto de Biología, Universidad Nacional Autónoma de México, Tercer Circuito s/n de CU, Mexico, DF, 04510, Mexico
| | - David A Coomes
- Forest Ecology and Conservation Group, Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EA, UK
| | - Esther Fichtler
- Department of Crop Sciences, Tropical Plant Production and Agricultural Systems Modelling, Göttingen University, Grisebachstrasse 6, 37077, Göttingen, Germany
| | - Matthias M Klepsch
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | | | - Daniel J McGlinn
- Department of Biology, College of Charleston, Charleston, SC, 29424, USA
| | - Elisabeth A Wheeler
- Department of Forest Biomaterials, NC State University, Raleigh, NC, 27695-8005, USA
- North Carolina Museum of Natural Sciences, 11 West Jones St., Raleigh, NC, 27601, USA
| | - Jingming Zheng
- Zheng JingminG, College of Forestry, Beijing Forestry University, Beijing, 100083, China
| | - Kasia Ziemińska
- Arnold Arboretum of Harvard University, 1300 Centre St, Boston, MA, 02130, USA
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
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21
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Zhang Y, Klepsch M, Jansen S. Bordered pits in xylem of vesselless angiosperms and their possible misinterpretation as perforation plates. PLANT, CELL & ENVIRONMENT 2017; 40:2133-2146. [PMID: 28667823 DOI: 10.1111/pce.13014] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 06/27/2017] [Indexed: 06/07/2023]
Abstract
Vesselless wood represents a rare phenomenon within the angiosperms, characterizing Amborellaceae, Trochodendraceae and Winteraceae. Anatomical observations of bordered pits and their pit membranes based on light, scanning and transmission electron microscopy (SEM and TEM) are required to understand functional questions surrounding vesselless angiosperms and the potential occurrence of cryptic vessels. Interconduit pit membranes in 11 vesselless species showed a similar ultrastructure as mesophytic vessel-bearing angiosperms, with a mean thickness of 245 nm (± 53, SD; n = six species). Shrunken, damaged and aspirated pit membranes, which were 52% thinner than pit membranes in fresh samples (n = four species), occurred in all dried-and-rehydrated samples, and in fresh latewood of Tetracentron sinense and Trochodendron aralioides. SEM demonstrated that shrunken pit membranes showed artificially enlarged, > 100 nm wide pores. Moreover, perfusion experiments with stem segments of Drimys winteri showed that 20 and 50 nm colloidal gold particles only passed through 2 cm long dried-and-rehydrated segments, but not through similar sized fresh ones. These results indicate that pit membrane shrinkage is irreversible and associated with a considerable increase in pore size. Moreover, our findings suggest that pit membrane damage, which may occur in planta, could explain earlier records of vessels in vesselless angiosperms.
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Affiliation(s)
- Ya Zhang
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Matthias Klepsch
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
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22
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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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23
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Trueba S, Pouteau R, Lens F, Feild TS, Isnard S, Olson ME, Delzon S. Vulnerability to xylem embolism as a major correlate of the environmental distribution of rain forest species on a tropical island. PLANT, CELL & ENVIRONMENT 2017; 40:277-289. [PMID: 27862015 DOI: 10.1111/pce.12859] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 10/28/2016] [Accepted: 11/01/2016] [Indexed: 05/09/2023]
Abstract
Increases in drought-induced tree mortality are being observed in tropical rain forests worldwide and are also likely to affect the geographical distribution of tropical vegetation. However, the mechanisms underlying the drought vulnerability and environmental distribution of tropical species have been little studied. We measured vulnerability to xylem embolism (P50 ) of 13 woody species endemic to New Caledonia and with different xylem conduit morphologies. We examined the relation between P50 , along with other leaf and xylem functional traits, and a range of habitat variables. Selected species had P50 values ranging between -4.03 and -2.00 MPa with most species falling in a narrow range of resistance to embolism above -2.7 MPa. Embolism vulnerability was significantly correlated with elevation, mean annual temperature and percentage of species occurrences located in rain forest habitats. Xylem conduit type did not explain variation in P50 . Commonly used functional traits such as wood density and leaf traits were not related to embolism vulnerability. Xylem embolism vulnerability stands out among other commonly used functional traits as a major driver of species environmental distribution. Drought-induced xylem embolism vulnerability behaves as a physiological trait closely associated with the habitat occupation of rain forest woody species.
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Affiliation(s)
| | - Robin Pouteau
- Institut Agronomique néo-Calédonien (IAC), Diversité biologique et fonctionnelle des écosystèmes terrestes, 98848, Noumea, New Caledonia
| | - Frederic Lens
- Naturalis Biodiversity Center, Leiden University, PO Box 9517, 2300RA, Leiden, The Netherlands
| | - Taylor S Feild
- Department of Ecology and Evolutionary Biology, Tulane University, New Orleans, LA, 70118, USA
| | | | - Mark E Olson
- Instituto de Biología, Universidad Nacional Autónoma de México, Tercer Circuito s/n de Ciudad Universitaria, México DF, 04510, Mexico
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24
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Scoffoni C, Albuquerque C, Brodersen CR, Townes SV, John GP, Cochard H, Buckley TN, McElrone AJ, Sack L. Leaf vein xylem conduit diameter influences susceptibility to embolism and hydraulic decline. THE NEW PHYTOLOGIST 2017; 213:1076-1092. [PMID: 27861926 DOI: 10.1111/nph.14256] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 09/10/2016] [Indexed: 05/24/2023]
Abstract
Ecosystems worldwide are facing increasingly severe and prolonged droughts during which hydraulic failure from drought-induced embolism can lead to organ or whole plant death. Understanding the determinants of xylem failure across species is especially critical in leaves, the engines of plant growth. If the vulnerability segmentation hypothesis holds within leaves, higher order veins that are most terminal in the plant hydraulic system should be more susceptible to embolism to protect the rest of the water transport system. Increased vulnerability in the higher order veins would also be consistent with these experiencing the greatest tensions in the plant xylem network. To test this hypothesis, we combined X-ray micro-computed tomography imaging, hydraulic experiments, cross-sectional anatomy and 3D physiological modelling to investigate how embolisms spread throughout petioles and vein orders during leaf dehydration in relation to conduit dimensions. Decline of leaf xylem hydraulic conductance (Kx ) during dehydration was driven by embolism initiating in petioles and midribs across all species, and Kx vulnerability was strongly correlated with petiole and midrib conduit dimensions. Our simulations showed no significant impact of conduit collapse on Kx decline. We found xylem conduit dimensions play a major role in determining the susceptibility of the leaf water transport system during strong leaf dehydration.
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Affiliation(s)
- 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 Biology, Utah State University, Logan, UT, 84322, USA
| | - Caetano Albuquerque
- Department of Viticulture and Enology, University of California, Davis, CA, 95616, USA
| | - Craig R Brodersen
- School of Forestry & Environmental Studies, Yale University, 195 Prospect Street, New Haven, CT, 06511, USA
| | - Shatara V Townes
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, 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
| | - Hervé Cochard
- PIAF, INRA, Univ. Clermont-Auvergne, Clermont-Ferrand, 63100, France
| | - Thomas N Buckley
- Plant Breeding Institute, Faculty of Agriculture and Environment, The University of Sydney, 12656 Newell Hwy, Narrabri, NSW, 2390, Australia
| | - Andrew J McElrone
- Department of Viticulture and Enology, University of California, Davis, CA, 95616, USA
- USDA-Agricultural Research Service, Davis, CA, 95616, 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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25
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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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Klepsch MM, Schmitt M, Paul Knox J, Jansen S. The chemical identity of intervessel pit membranes in Acer challenges hydrogel control of xylem hydraulic conductivity. AOB PLANTS 2016; 8:plw052. [PMID: 27354661 PMCID: PMC4975070 DOI: 10.1093/aobpla/plw052] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 06/10/2016] [Indexed: 05/03/2023]
Abstract
Ion-mediated enhancement of the hydraulic conductivity of xylem tissue (i.e. the ionic effect) has been reported for various angiosperm species. One explanation of the ionic effect is that it is caused by the swelling and shrinking of intervessel pit membranes due to the presence of pectins and/or other cell-wall matrix polymers such as heteroxylans or arabinogalactan-proteins (AGPs) that may contain acidic sugars. Here, we examined the ionic effect for six Acer species and their pit membrane chemistry using immunocytochemistry, including antibodies against glycoproteins. Moreover, anatomical features related to the bordered pit morphology and vessel dimensions were investigated using light and electron microscopy. The ionic effect varied from 18 % (± 9) to 32 % (± 13). Epitopes of homogalacturonan (LM18) and xylan (LM11) were not detected in intervessel pit membranes. Negative results were also obtained for glycoproteins (extensin: LM1, JIM20; AGP glycan: LM2), although AGP (JIM13)-related epitopes were detected in parenchyma cells. The mean vessel length was significantly correlated with the magnitude of the ionic effect, unlike other pit or vessel-related characteristics. Our results suggest that intervessel pit membranes of Acer are unlikely to contain pectic or other acidic polysaccharides. Therefore, alternative explanations should be tested to clarify the ionic effect.
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Affiliation(s)
- Matthias M Klepsch
- Institute for Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, D-89081 Ulm, Germany
| | - Marco Schmitt
- Institute for Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, D-89081 Ulm, Germany
| | - J Paul Knox
- Centre for Plant Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Steven Jansen
- Institute for Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, D-89081 Ulm, Germany
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27
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Schenk HJ, Espino S, Visser A, Esser BK. Dissolved atmospheric gas in xylem sap measured with membrane inlet mass spectrometry. PLANT, CELL & ENVIRONMENT 2016; 39:944-50. [PMID: 26868162 DOI: 10.1111/pce.12678] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 11/07/2015] [Indexed: 05/13/2023]
Abstract
A new method is described for measuring dissolved gas concentrations in small volumes of xylem sap using membrane inlet mass spectrometry. The technique can be used to determine concentrations of atmospheric gases, such as argon, as reported here, or for any dissolved gases and their isotopes for a variety of applications, such as rapid detection of trace gases from groundwater only hours after they were taken up by trees and rooting depth estimation. Atmospheric gas content in xylem sap directly affects the conditions and mechanisms that allow for gas removal from xylem embolisms, because gas can dissolve into saturated or supersaturated sap only under gas pressure that is above atmospheric pressure. The method was tested for red trumpet vine, Distictis buccinatoria (Bignoniaceae), by measuring atmospheric gas concentrations in sap collected at times of minimum and maximum daily temperature and during temperature increase and decline. Mean argon concentration in xylem sap did not differ significantly from saturation levels for the temperature and pressure conditions at any time of collection, but more than 40% of all samples were supersaturated, especially during the warm parts of day. There was no significant diurnal pattern, due to high variability between samples.
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Affiliation(s)
- H Jochen Schenk
- Department of Biological Science, California State University Fullerton, 800 N. State College Boulevard, Fullerton, CA, 92831, USA
| | - Susana Espino
- Department of Biological Science, California State University Fullerton, 800 N. State College Boulevard, Fullerton, CA, 92831, USA
| | - Ate Visser
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA, 94550, USA
| | - Bradley K Esser
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA, 94550, USA
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