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Li Y, Hoch G. The sensitivity of root water uptake to cold root temperature follows species-specific upper elevational distribution limits of temperate tree species. PLANT, CELL & ENVIRONMENT 2024; 47:2192-2205. [PMID: 38481108 DOI: 10.1111/pce.14874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 02/21/2024] [Accepted: 02/24/2024] [Indexed: 04/30/2024]
Abstract
Physiological water stress induced by low root temperatures might contribute to species-specific climatic limits of tree distribution. We investigated the low temperature sensitivity of root water uptake and transport in seedlings of 16 European tree species which reach their natural upper elevation distribution limits at different distances to the alpine treeline. We used 2H-H2O pulse-labelling to quantify the water uptake and transport velocity from roots to leaves in seedlings exposed to constant 15°C, 7°C or 2°C root temperature, but identical aboveground temperatures between 20°C and 25°C. In all species, low root temperatures reduced the water transport rate, accompanied by reduced stem water potentials and stomatal conductance. At 7°C root temperature, the relative water uptake rates among species correlated positively with the species-specific upper elevation limits, indicating an increasingly higher sensitivity to lower root zone temperatures, the lower a species' natural elevational distribution limit. Conversely, 2°C root temperature severely inhibited water uptake in all species, irrespective of the species' thermal elevational limits. We conclude that low temperature-induced hydraulic constraints contribute to the cold distribution limits of temperate tree species and are a potential physiological cause behind the low temperature limits of plant growth in general.
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Affiliation(s)
- Yating Li
- Department of Environmental Sciences-Botany, University of Basel, Basel, Switzerland
| | - Günter Hoch
- Department of Environmental Sciences-Botany, University of Basel, Basel, Switzerland
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2
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Voothuluru P, Wu Y, Sharp RE. Not so hidden anymore: Advances and challenges in understanding root growth under water deficits. THE PLANT CELL 2024; 36:1377-1409. [PMID: 38382086 PMCID: PMC11062450 DOI: 10.1093/plcell/koae055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 02/09/2024] [Accepted: 02/15/2024] [Indexed: 02/23/2024]
Abstract
Limited water availability is a major environmental factor constraining plant development and crop yields. One of the prominent adaptations of plants to water deficits is the maintenance of root growth that enables sustained access to soil water. Despite early recognition of the adaptive significance of root growth maintenance under water deficits, progress in understanding has been hampered by the inherent complexity of root systems and their interactions with the soil environment. We highlight selected milestones in the understanding of root growth responses to water deficits, with emphasis on founding studies that have shaped current knowledge and set the stage for further investigation. We revisit the concept of integrated biophysical and metabolic regulation of plant growth and use this framework to review central growth-regulatory processes occurring within root growth zones under water stress at subcellular to organ scales. Key topics include the primary processes of modifications of cell wall-yielding properties and osmotic adjustment, as well as regulatory roles of abscisic acid and its interactions with other hormones. We include consideration of long-recognized responses for which detailed mechanistic understanding has been elusive until recently, for example hydrotropism, and identify gaps in knowledge, ongoing challenges, and opportunities for future research.
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Affiliation(s)
- Priya Voothuluru
- Division of Plant Science and Technology, University of Missouri, Columbia, MO 65211, USA
- Interdisciplinary Plant Group, University of Missouri, Columbia, MO 65211, USA
| | - Yajun Wu
- Department of Biology and Microbiology, South Dakota State University, Brookings, SD 57007, USA
| | - Robert E Sharp
- Division of Plant Science and Technology, University of Missouri, Columbia, MO 65211, USA
- Interdisciplinary Plant Group, University of Missouri, Columbia, MO 65211, USA
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3
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Sportes A, Hériché M, Mounier A, Durney C, van Tuinen D, Trouvelot S, Wipf D, Courty PE. Comparative RNA sequencing-based transcriptome profiling of ten grapevine rootstocks: shared and specific sets of genes respond to mycorrhizal symbiosis. MYCORRHIZA 2023; 33:369-385. [PMID: 37561219 DOI: 10.1007/s00572-023-01119-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 06/23/2023] [Indexed: 08/11/2023]
Abstract
Arbuscular mycorrhizal symbiosis improves water and nutrient uptake by plants and provides them other ecosystem services. Grapevine is one of the major crops in the world. Vitis vinifera scions generally are grafted onto a variety of rootstocks that confer different levels of resistance against different pests, tolerance to environmental stress, and influence the physiology of the scions. Arbuscular mycorrhizal fungi are involved in the root architecture and in the immune response to soil-borne pathogens. However, the fine-tuned regulation and the transcriptomic plasticity of rootstocks in response to mycorrhization are still unknown. We compared the responses of 10 different grapevine rootstocks to arbuscular mycorrhizal symbiosis (AMS) formed with Rhizophagus irregularis DAOM197198 using RNA sequencing-based transcriptome profiling. We have highlighted a few shared regulation mechanisms, but also specific rootstock responses to R. irregularis colonization. A set of 353 genes was regulated by AMS in all ten rootstocks. We also compared the expression level of this set of genes to more than 2000 transcriptome profiles from various grapevine varieties and tissues to identify a class of transcripts related to mycorrhizal associations in these 10 rootstocks. Then, we compared the response of the 351 genes upregulated by mycorrhiza in grapevine to their Medicago truncatula homologs in response to mycorrhizal colonization based on available transcriptomic studies. More than 97% of the 351 M. truncatula-homologous grapevine genes were expressed in at least one mycorrhizal transcriptomic study, and 64% in every single RNAseq dataset. At the intra-specific level, we described, for the first time, shared and specific grapevine rootstock genes in response to R. irregularis symbiosis. At the inter-specific level, we defined a shared subset of mycorrhiza-responsive genes.
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Affiliation(s)
- Antoine Sportes
- Agroécologie, INRAE, Institut Agro, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Mathilde Hériché
- Agroécologie, INRAE, Institut Agro, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Arnaud Mounier
- Agroécologie, INRAE, Institut Agro, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Célien Durney
- Agroécologie, INRAE, Institut Agro, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Diederik van Tuinen
- Agroécologie, INRAE, Institut Agro, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Sophie Trouvelot
- Agroécologie, INRAE, Institut Agro, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Daniel Wipf
- Agroécologie, INRAE, Institut Agro, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Pierre Emmanuel Courty
- Agroécologie, INRAE, Institut Agro, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France.
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Pan X, Wang P, Wei X, Zhang J, Xu B, Chen Y, Wei G, Wang Z. Exploring root system architecture and anatomical variability in alfalfa (Medicago sativa L.) seedlings. BMC PLANT BIOLOGY 2023; 23:449. [PMID: 37743492 PMCID: PMC10519072 DOI: 10.1186/s12870-023-04469-4] [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: 04/27/2023] [Accepted: 09/16/2023] [Indexed: 09/26/2023]
Abstract
BACKGROUND The growth of alfalfa (Medicago sativa L.) is significantly hampered by drought and nutrient deficiencies. The identification of root architectural and anatomical characteristics holds paramount importance for the development of alfalfa genotypes with enhanced adaptation to adverse environmental conditions. In this study, we employed a visual rhizobox system to investigate the variability in root system architecture (including root depth, root length, root tips number, etc.), anatomical features (such as cortical traits, total stele area, number and area of vessel, etc.), as well as nitrogen and phosphorus uptake across 53 alfalfa genotypes during the seedling stage. RESULTS Out of the 42 traits measured, 21 root traits, along with nitrogen (N) and phosphorus (P) uptake, displayed higher coefficients of variation (CVs ≥ 0.25) among the tested genotypes. Local root morphological and anatomical traits exhibited more significant variation than global root traits. Twenty-three traits with CVs ≥ 0.25 constituted to six principal components (eigenvalues > 1), collectively accounting for 88.0% of the overall genotypic variation. Traits such as total root length, number of root tips, maximal root depth, and others exhibited positive correlations with shoot dry mass and root dry mass. Additionally, total stele area and xylem vessel area showed positive correlations with N and P uptake. CONCLUSIONS These root traits, which have demonstrated associations with biomass and nutrient uptake, may be considered for the breeding of alfalfa genotypes that possess efficient resource absorption and increased adaptability to abiotic stress, following validation during the entire growth period in the field.
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Affiliation(s)
- Xinya Pan
- College of Grassland Agriculture, Northwest A&F University, 3 Taicheng Road, Yangling, 712100, China
| | - Pengfei Wang
- College of Grassland Agriculture, Northwest A&F University, 3 Taicheng Road, Yangling, 712100, China
| | - Xianwei Wei
- College of Grassland Agriculture, Northwest A&F University, 3 Taicheng Road, Yangling, 712100, China
| | - Jinxin Zhang
- College of Grassland Agriculture, Northwest A&F University, 3 Taicheng Road, Yangling, 712100, China
| | - Bingcheng Xu
- College of Grassland Agriculture, Northwest A&F University, 3 Taicheng Road, Yangling, 712100, China
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, 26 Xinong Road, Yangling, 712100, China
| | - Yinglong Chen
- The UWA Institute of Agriculture, School of Agriculture and Environment, The University of Western Australia, Perth, WA, 6001, Australia
| | - Gehong Wei
- College of Life Sciences, Northwest A&F University, 22 Xinong Road, Yangling, 712100, China
| | - Zhi Wang
- College of Grassland Agriculture, Northwest A&F University, 3 Taicheng Road, Yangling, 712100, China.
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, 26 Xinong Road, Yangling, 712100, China.
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Grünhofer P, Heimerich I, Herzig L, Pohl S, Schreiber L. Apoplastic barriers of Populus × canescens roots in reaction to different cultivation conditions and abiotic stress treatments. STRESS BIOLOGY 2023; 3:24. [PMID: 37676401 PMCID: PMC10441858 DOI: 10.1007/s44154-023-00103-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 07/04/2023] [Indexed: 09/08/2023]
Abstract
Populus is an important tree genus frequently cultivated for economical purposes. However, the high sensitivity of poplars towards water deficit, drought, and salt accumulation significantly affects plant productivity and limits biomass yield. Various cultivation and abiotic stress conditions have been described to significantly induce the formation of apoplastic barriers (Casparian bands and suberin lamellae) in roots of different monocotyledonous crop species. Thus, this study aimed to investigate to which degree the roots of the dicotyledonous gray poplar (Populus × canescens) react to a set of selected cultivation conditions (hydroponics, aeroponics, or soil) and abiotic stress treatments (abscisic acid, oxygen deficiency) because a differing stress response could potentially help in explaining the observed higher stress susceptibility. The apoplastic barriers of poplar roots cultivated in different environments were analyzed by means of histochemistry and gas chromatography and compared to the available literature on monocotyledonous crop species. Overall, dicotyledonous poplar roots showed only a remarkably low induction or enhancement of apoplastic barriers in response to the different cultivation conditions and abiotic stress treatments. The genetic optimization (e.g., overexpression of biosynthesis key genes) of the apoplastic barrier development in poplar roots might result in more stress-tolerant cultivars in the future.
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Affiliation(s)
- Paul Grünhofer
- Department of Ecophysiology, Institute of Cellular and Molecular Botany, University of Bonn, Kirschallee 1, 53115, Bonn, Germany.
| | - Ines Heimerich
- Department of Ecophysiology, Institute of Cellular and Molecular Botany, University of Bonn, Kirschallee 1, 53115, Bonn, Germany
| | - Lena Herzig
- Department of Ecophysiology, Institute of Cellular and Molecular Botany, University of Bonn, Kirschallee 1, 53115, Bonn, Germany
| | - Svenja Pohl
- Department of Ecophysiology, Institute of Cellular and Molecular Botany, University of Bonn, Kirschallee 1, 53115, Bonn, Germany
| | - Lukas Schreiber
- Department of Ecophysiology, Institute of Cellular and Molecular Botany, University of Bonn, Kirschallee 1, 53115, Bonn, Germany
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Labarga D, Mairata A, Puelles M, Martín I, Albacete A, García-Escudero E, Pou A. The Rootstock Genotypes Determine Drought Tolerance by Regulating Aquaporin Expression at the Transcript Level and Phytohormone Balance. PLANTS (BASEL, SWITZERLAND) 2023; 12:718. [PMID: 36840066 PMCID: PMC9961603 DOI: 10.3390/plants12040718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 01/27/2023] [Accepted: 02/01/2023] [Indexed: 06/18/2023]
Abstract
Grapevine rootstocks may supply water to the scion according to the transpiration demand, thus modulating plant responses to water deficit, but the scion variety can alter these responses, as well. The rootstock genotypes' effect on the scion physiological response, aquaporin expression, and hormone concentrations in the xylem and the leaf was assessed under well watered (WW) and water stress (WS) conditions. Under WW, vines grafted onto 1103P and R110 rootstocks (the more vigorous and drought-tolerant) showed higher photosynthesis (AN), stomatal conductance (gs), and hydraulic conductance (Khplant) compared with the less vigorous and drought-sensitive rootstock (161-49C), while under WS, there were hardly any differences between vines depending on the rootstock grafted. Besides, stomatal traits were affected by drought, which was related to gs, but not by the rootstock. Under WS conditions, all VvPIP and VvTIP aquaporins were up-regulated in the vines grafted onto 1103P and down-regulated in the ones grafted onto 161-49C. The 1103P capability to tolerate drought was enhanced by the up-regulation of all VvPIP and VvTIP aquaporins, lower ABA synthesis, and higher ACC/ABA ratios in leaves during WS compared with 161-49C. It was concluded that, under WW conditions, transpiration and stomatal control were rootstock-dependent. However, under WS conditions, alterations in the molecular components of water transport and hormone concentration of the scion resulted in similar gas exchange values in the studied scions grafted onto different rootstocks.
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Affiliation(s)
- David Labarga
- Departamento de Viticultura, Instituto de Ciencias de la Vid y del Vino (Gobierno de La Rioja, Universidad de La Rioja, CSIC), Finca La Grajera, Ctra. De Burgos km 6, 26007 Logroño, Spain
| | - Andreu Mairata
- Departamento de Viticultura, Instituto de Ciencias de la Vid y del Vino (Gobierno de La Rioja, Universidad de La Rioja, CSIC), Finca La Grajera, Ctra. De Burgos km 6, 26007 Logroño, Spain
| | - Miguel Puelles
- Departamento de Viticultura, Instituto de Ciencias de la Vid y del Vino (Gobierno de La Rioja, Universidad de La Rioja, CSIC), Finca La Grajera, Ctra. De Burgos km 6, 26007 Logroño, Spain
| | - Ignacio Martín
- Departamento de Viticultura, Instituto de Ciencias de la Vid y del Vino (Gobierno de La Rioja, Universidad de La Rioja, CSIC), Finca La Grajera, Ctra. De Burgos km 6, 26007 Logroño, Spain
| | - Alfonso Albacete
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura (CEBAS), Consejo Superior de Investigaciones Científicas (CSIC), Campus Universitario de Espinardo, Espinardo, 30100 Murcia, Spain
| | - Enrique García-Escudero
- Departamento de Viticultura, Instituto de Ciencias de la Vid y del Vino (Gobierno de La Rioja, Universidad de La Rioja, CSIC), Finca La Grajera, Ctra. De Burgos km 6, 26007 Logroño, Spain
| | - Alicia Pou
- Departamento de Viticultura, Instituto de Ciencias de la Vid y del Vino (Gobierno de La Rioja, Universidad de La Rioja, CSIC), Finca La Grajera, Ctra. De Burgos km 6, 26007 Logroño, Spain
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Israel D, Lee SH, Robson TM, Zwiazek JJ. Plasma membrane aquaporins of the PIP1 and PIP2 subfamilies facilitate hydrogen peroxide diffusion into plant roots. BMC PLANT BIOLOGY 2022; 22:566. [PMID: 36471241 PMCID: PMC9721007 DOI: 10.1186/s12870-022-03962-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 11/24/2022] [Indexed: 06/17/2023]
Abstract
BACKGROUND The permeability of plasma membrane aquaporins (PIPs) to small solutes other than water greatly diversifies their potential functions in plant development and metabolic processes. One such process is stress signalling in which hydrogen peroxide (H2O2) plays a major role. Based on transport assays carried out in yeast, there are differences in the degree to which PIPs of Arabidopsis thaliana, are permeable to H2O2 and thus they may differentially facilitate transmembrane diffusion. Here, we test whether specific PIPs aid in the transmembrane diffusion of H2O2 to such an extent that knocking-out PIPs affects plant phenotype. We examined changes in growth and morphology, including biomass accumulation, root system architecture and relative water content, as well as gas exchange, across two H2O2 treatments in knockout mutants of A. thaliana. RESULTS We could infer that PIP-type aquaporins are permeable to H2O2 in planta and that this permeability is physiologically relevant in a plant's response to oxidative stress. In particular, the lack of functional PIP2;3 confers resistance to exogenously applied H2O2 indicating that it facilitates H2O2 entry into root cells. Additionally, PIP1;1 and PIP2;6 were found to facilitate H2O2 diffusion, while PIP2;2 is required for proper root growth under controlled conditions. MAIN FINDINGS We conclude that PIPs are physiologically relevant conduits for H2O2 diffusion in the A. thaliana roots and participate in the regulation of stress responses.
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Affiliation(s)
- David Israel
- Organismal and Evolutionary Biology (OEB), Viikki Plant Science Centre (ViPS), University of Helsinki, PO Box 65, 00014 Helsinki, Finland
- Department of Renewable Resources, University of Alberta, 438 Earth Sciences Building, 11223 Saskatchewan Drive NW, Edmonton, AB T6G 2E3 Canada
| | - Seong Hee Lee
- Department of Renewable Resources, University of Alberta, 438 Earth Sciences Building, 11223 Saskatchewan Drive NW, Edmonton, AB T6G 2E3 Canada
| | - Thomas Matthew Robson
- Organismal and Evolutionary Biology (OEB), Viikki Plant Science Centre (ViPS), University of Helsinki, PO Box 65, 00014 Helsinki, Finland
- The National School of Forestry, University of Cumbria, Rydal Road, Ambleside, LA22 9BB UK
| | - Janusz Jerzy Zwiazek
- Department of Renewable Resources, University of Alberta, 438 Earth Sciences Building, 11223 Saskatchewan Drive NW, Edmonton, AB T6G 2E3 Canada
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Boursiac Y, Pradal C, Bauget F, Lucas M, Delivorias S, Godin C, Maurel C. Phenotyping and modeling of root hydraulic architecture reveal critical determinants of axial water transport. PLANT PHYSIOLOGY 2022; 190:1289-1306. [PMID: 35708646 PMCID: PMC9516777 DOI: 10.1093/plphys/kiac281] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 05/15/2022] [Indexed: 05/26/2023]
Abstract
Water uptake by roots is a key adaptation of plants to aerial life. Water uptake depends on root system architecture (RSA) and tissue hydraulic properties that, together, shape the root hydraulic architecture. This work investigates how the interplay between conductivities along radial (e.g. aquaporins) and axial (e.g. xylem vessels) pathways determines the water transport properties of highly branched RSAs as found in adult Arabidopsis (Arabidopsis thaliana) plants. A hydraulic model named HydroRoot was developed, based on multi-scale tree graph representations of RSAs. Root water flow was measured by the pressure chamber technique after successive cuts of a same root system from the tip toward the base. HydroRoot model inversion in corresponding RSAs allowed us to concomitantly determine radial and axial conductivities, providing evidence that the latter is often overestimated by classical evaluation based on the Hagen-Poiseuille law. Organizing principles of Arabidopsis primary and lateral root growth and branching were determined and used to apply the HydroRoot model to an extended set of simulated RSAs. Sensitivity analyses revealed that water transport can be co-limited by radial and axial conductances throughout the whole RSA. The number of roots that can be sectioned (intercepted) at a given distance from the base was defined as an accessible and informative indicator of RSA. The overall set of experimental and theoretical procedures was applied to plants mutated in ESKIMO1 and previously shown to have xylem collapse. This approach will be instrumental to dissect the root water transport phenotype of plants with intricate alterations in root growth or transport functions.
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Affiliation(s)
| | | | | | | | - Stathis Delivorias
- Institute for Plant Sciences of Montpellier (IPSiM), Univ Montpellier, CNRS, INRAE, Institut Agro, Montpellier 34060, France
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9
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Clément C, Schneider HM, Dresbøll DB, Lynch JP, Thorup-Kristensen K. Root and xylem anatomy varies with root length, root order, soil depth and environment in intermediate wheatgrass (Kernza®) and alfalfa. ANNALS OF BOTANY 2022; 130:367-382. [PMID: 35468194 PMCID: PMC9486898 DOI: 10.1093/aob/mcac058] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 04/25/2022] [Indexed: 06/08/2023]
Abstract
BACKGROUND AND AIMS Deep roots (i.e. >1 m depth) are important for crops to access water when the topsoil is dry. Root anatomy and hydraulic conductance play important roles in the uptake of soil water, particularly water located deep in the soil. We investigated whether root and xylem anatomy vary as a function of root type, order and length, or with soil depth in roots of two deep-rooted perennial crops: intermediate wheatgrass [Thinopyrum intermedium (Kernza®)] and alfalfa (Medicago sativa). We linked the expression of these anatomical traits to the plants' capacity to take up water from deep soil layers. METHODS Using laser ablation tomography, we compared the roots of the two crops for cortical area, number and size of metaxylem vessels, and their estimated root axial hydraulic conductance (ERAHCe). The deepest roots investigated were located at soil depths of 2.25 and at 3.5 m in the field and in rhizoboxes, respectively. Anatomical differences were characterized along 1-m-long individual roots, among root types and orders, as well as between environmental conditions. KEY RESULTS For both crops, a decrease in the number and diameter, or both, of metaxylem vessels along individual root segments and with soil depth in the field resulted in a decrease in ERAHCe. Alfalfa, with a greater number of metaxylem vessels per root throughout the soil profile and, on average, a 4-fold greater ERAHCe, took up more water from the deep soil layers than intermediate wheatgrass. Root anatomical traits were significantly different across root types, classes and growth conditions. CONCLUSIONS Root anatomical traits are important tools for the selection of crops with enhanced exploitation of deep soil water. The development and breeding of perennial crops for improved subsoil exploitation will be aided by greater understanding of root phenotypes linked to deep root growth and activity.
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Affiliation(s)
| | - Hannah M Schneider
- Department of Plant Science, Pennsylvania State University, University Park, PA 16802, USA
| | - Dorte Bodin Dresbøll
- Department of Plant and Environmental Science, University of Copenhagen, 1871 Frederiksberg, Denmark
| | - Jonathan P Lynch
- Department of Plant Science, Pennsylvania State University, University Park, PA 16802, USA
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10
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Bourbia I, Lucani C, Brodribb TJ. Constant hydraulic supply enables optical monitoring of transpiration in a grass, a herb, and a conifer. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:5625-5633. [PMID: 35727898 PMCID: PMC9467656 DOI: 10.1093/jxb/erac241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Accepted: 05/26/2022] [Indexed: 06/15/2023]
Abstract
Plant transpiration is an inevitable consequence of photosynthesis and has a huge impact on the terrestrial carbon and water cycle, yet accurate and continuous monitoring of its dynamics is still challenging. Under well-watered conditions, canopy transpiration (Ec) could potentially be continuously calculated from stem water potential (Ψstem), but only if the root to stem hydraulic conductance (Kr-s) remains constant and plant capacitance is relatively small. We tested whether such an approach is viable by investigating whether Kr-s remains constant under a wide range of daytime transpiration rates in non-water-stressed plants. Optical dendrometers were used to continuously monitor tissue shrinkage, an accurate proxy of Ψstem, while Ec was manipulated in three species with contrasting morphological, anatomical, and phylogenetic identities: Tanacetum cinerariifolium, Zea mays, and Callitris rhomboidea. In all species, we found Kr-s to remain constant across a wide range of Ec, meaning that the dynamics of Ψstem could be used to monitor Ec. This was evidenced by the close agreement between measured Ec and that predicted from optically measured Ψstem. These results suggest that optical dendrometers enable both plant hydration and Ec to be monitored non-invasively and continuously in a range of woody and herbaceous species. This technique presents new opportunities to monitor transpiration under laboratory and field conditions in a diversity of woody, herbaceous, and grassy species.
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Affiliation(s)
- Ibrahim Bourbia
- School of Natural Sciences, University of Tasmania, Hobart, Tas, Australia
| | - Christopher Lucani
- School of Natural Sciences, University of Tasmania, Hobart, Tas, Australia
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11
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Li Z, Wang S, Wang W, Gu J, Wang Y. The Hierarchy of Protoxylem Groupings in Primary Root and Their Plasticity to Nitrogen Addition in Three Tree Species. FRONTIERS IN PLANT SCIENCE 2022; 13:903318. [PMID: 35812911 PMCID: PMC9260270 DOI: 10.3389/fpls.2022.903318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 06/01/2022] [Indexed: 06/15/2023]
Abstract
Protoxylem grouping (PG), a classification based on the number of protoxylem poles, is a crucial indicator related to other functional traits in fine roots, affecting growth and survival of individual root. However, within root system, less is known about the arrangement of PG. Moreover, the responses of PG to fertilization are still unclear. Here, we selected three common hardwood species in Northeast China, Juglans mandshurica, Fraxinus mandshurica, and Phellodendron amurense, conducted root pruning and nutrient addition. In this study, we analyzed the PG, morphology, and other anatomy traits of newly formed root branches. The results showed all root length, diameter, and stele, as well as hydraulic conductivity, were significantly positive related to the PG number, and the PG number generally decreased with ascending root developmental order; these patterns were independent of species and fertilization. Additionally, we also found the plasticity of PGs to environmental changes, in terms of the increased frequency of high PG roots after fertilization, significantly in J. mandshurica and F. mandshurica. Therefore, the heterogeneity, hierarchy, and plasticity of individual roots within root system may be widespread in woody plants, which is of great significance to deepen our understanding in root growth and development, as well as the belowground ecological process.
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Affiliation(s)
- Zhongyue Li
- Mountain Tai Forest Ecosystem Research Station of State Forestry and Grassland Administration, College of Forestry, Shandong Agricultural University, Tai’an, China
| | - Siyuan Wang
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin, China
| | - Wenna Wang
- Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Jiacun Gu
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin, China
| | - Yan Wang
- Mountain Tai Forest Ecosystem Research Station of State Forestry and Grassland Administration, College of Forestry, Shandong Agricultural University, Tai’an, China
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12
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Zhou M, Guo Y, Sheng J, Yuan Y, Zhang WH, Bai W. Using anatomical traits to understand root functions across root orders of herbaceous species in a temperate steppe. THE NEW PHYTOLOGIST 2022; 234:422-434. [PMID: 35048364 DOI: 10.1111/nph.17978] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Accepted: 01/03/2022] [Indexed: 06/14/2023]
Abstract
Root anatomical traits play crucial roles in understanding root functions and root form-function linkages. However, the root anatomy and form-function linkages of monocotyledonous and dicotyledonous herbs remain largely unknown. We measured order-based anatomical traits and mycorrhizal colonization rates of 32 perennial herbs of monocotyledons and dicotyledons in a temperate steppe. For monocots, relative constant proportion of cortex and mycorrhizal colonization rates, but increased cell-wall thickening of the endodermis and proportion of stele were observed across root orders, indicating a slight reduction in absorption capacity and improvement in transportation capacity across orders. For dicots, the cortex and mycorrhizal colonization disappeared in the fourth-order and/or fifth-order roots, whereas the secondary vascular tissue increased markedly, suggesting significant transition of root functions from absorption to transportation across root orders. The allometric relationships between stele and cortex differed across root orders and plant groups, suggesting different strategies to coordinate the absorption and transportation functions among plant groups. In summary, our results revealed different functional transition patterns across root orders and distinct strategies for coordinating the absorption and transportation of root system between monocots and dicots. These findings will contribute to our understanding of the root form and functions in herbaceous species.
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Affiliation(s)
- Meng Zhou
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China
| | - Yumeng Guo
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jun Sheng
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yujia Yuan
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wen-Hao Zhang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wenming Bai
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China
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13
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Bartlett MK, Sinclair G, Fontanesi G, Knipfer T, Walker MA, McElrone AJ. Root pressure-volume curve traits capture rootstock drought tolerance. ANNALS OF BOTANY 2022; 129:389-402. [PMID: 34668965 PMCID: PMC8944712 DOI: 10.1093/aob/mcab132] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 10/18/2021] [Indexed: 06/01/2023]
Abstract
BACKGROUND AND AIMS Living root tissues significantly constrain plant water uptake under drought, but we lack functional traits to feasibly screen diverse plants for variation in the drought responses of these tissues. Water stress causes roots to lose volume and turgor, which are crucial to root structure, hydraulics and growth. Thus, we hypothesized that root pressure-volume (p-v) curve traits, which quantify the effects of water potential on bulk root turgor and volume, would capture differences in rootstock drought tolerance. METHODS We used a greenhouse experiment to evaluate relationships between root p-v curve traits and gas exchange, whole-plant hydraulic conductance and biomass under drought for eight grapevine rootstocks that varied widely in drought performance in field trials (101-14, 110R, 420A, 5C, 140-Ru, 1103P, Ramsey and Riparia Gloire), grafted to the same scion variety (Vitis vinifera 'Chardonnay'). KEY RESULTS The traits varied significantly across rootstocks, and droughted vines significantly reduced root turgor loss point (πtlp), osmotic potential at full hydration (πo) and capacitance (C), indicating that roots became less susceptible to turgor loss and volumetric shrinkage. Rootstocks that retained a greater root volume (i.e. a lower C) also maintained more gas exchange under drought. The rootstocks that previous field trials have classified as drought tolerant exhibited significantly lower πtlp, πo and C values in well-watered conditions, but significantly higher πo and πtlp values under water stress, than the varieties classified as drought sensitive. CONCLUSIONS These findings suggest that acclimation in root p-v curve traits improves gas exchange in persistently dry conditions, potentially through impacts on root hydraulics or root to shoot chemical signalling. However, retaining turgor and volume in previously unstressed roots, as these roots deplete wet soil to moderately negative water potentials, could be more important to drought performance in the deep, highly heterogenous rooting zones which grapevines develop under field conditions.
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Affiliation(s)
| | - G Sinclair
- Department of Viticulture & Enology, University of
California, Davis, CA, USA
| | - G Fontanesi
- Department of Viticulture & Enology, University of
California, Davis, CA, USA
| | - T Knipfer
- Department of Viticulture & Enology, University of
California, Davis, CA, USA
- Faculty of Land and Food Systems, The University of British
Columbia, Vancouver, British Columbia, Canada
| | - M A Walker
- Department of Viticulture & Enology, University of
California, Davis, CA, USA
| | - A J McElrone
- Department of Viticulture & Enology, University of
California, Davis, CA, USA
- USDA-ARS, Crops Pathology and Genetics Research Unit,
Davis, CA, USA
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14
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Boursiac Y, Protto V, Rishmawi L, Maurel C. Experimental and conceptual approaches to root water transport. PLANT AND SOIL 2022; 478:349-370. [PMID: 36277078 PMCID: PMC9579117 DOI: 10.1007/s11104-022-05427-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 04/03/2022] [Indexed: 05/05/2023]
Abstract
BACKGROUND Root water transport, which critically contributes to the plant water status and thereby plant productivity, has been the object of extensive experimental and theoretical studies. However, root systems represent an intricate assembly of cells in complex architectures, including many tissues at distinct developmental stages. Our comprehension of where and how molecular actors integrate their function in order to provide the root with its hydraulic properties is therefore still limited. SCOPE Based on current literature and prospective discussions, this review addresses how root water transport can be experimentally measured, what is known about the underlying molecular actors, and how elementary water transport processes are scaled up in numerical/mathematical models. CONCLUSIONS The theoretical framework and experimental procedures on root water transport that are in use today have been established a few decades ago. However, recent years have seen the appearance of new techniques and models with enhanced resolution, down to a portion of root or to the tissue level. These advances pave the way for a better comprehension of the dynamics of water uptake by roots in the soil.
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Affiliation(s)
- Yann Boursiac
- IPSiM, Univ Montpellier, CNRS, INRAE, Institut Agro, 34060 Montpellier, France
| | - Virginia Protto
- IPSiM, Univ Montpellier, CNRS, INRAE, Institut Agro, 34060 Montpellier, France
| | - Louai Rishmawi
- IPSiM, Univ Montpellier, CNRS, INRAE, Institut Agro, 34060 Montpellier, France
| | - Christophe Maurel
- IPSiM, Univ Montpellier, CNRS, INRAE, Institut Agro, 34060 Montpellier, France
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15
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Freschet GT, Pagès L, Iversen CM, Comas LH, Rewald B, Roumet C, Klimešová J, Zadworny M, Poorter H, Postma JA, Adams TS, Bagniewska‐Zadworna A, Bengough AG, Blancaflor EB, Brunner I, Cornelissen JHC, Garnier E, Gessler A, Hobbie SE, Meier IC, Mommer L, Picon‐Cochard C, Rose L, Ryser P, Scherer‐Lorenzen M, Soudzilovskaia NA, Stokes A, Sun T, Valverde‐Barrantes OJ, Weemstra M, Weigelt A, Wurzburger N, York LM, Batterman SA, Gomes de Moraes M, Janeček Š, Lambers H, Salmon V, Tharayil N, McCormack ML. A starting guide to root ecology: strengthening ecological concepts and standardising root classification, sampling, processing and trait measurements. THE NEW PHYTOLOGIST 2021; 232:973-1122. [PMID: 34608637 PMCID: PMC8518129 DOI: 10.1111/nph.17572] [Citation(s) in RCA: 99] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 03/22/2021] [Indexed: 05/17/2023]
Abstract
In the context of a recent massive increase in research on plant root functions and their impact on the environment, root ecologists currently face many important challenges to keep on generating cutting-edge, meaningful and integrated knowledge. Consideration of the below-ground components in plant and ecosystem studies has been consistently called for in recent decades, but methodology is disparate and sometimes inappropriate. This handbook, based on the collective effort of a large team of experts, will improve trait comparisons across studies and integration of information across databases by providing standardised methods and controlled vocabularies. It is meant to be used not only as starting point by students and scientists who desire working on below-ground ecosystems, but also by experts for consolidating and broadening their views on multiple aspects of root ecology. Beyond the classical compilation of measurement protocols, we have synthesised recommendations from the literature to provide key background knowledge useful for: (1) defining below-ground plant entities and giving keys for their meaningful dissection, classification and naming beyond the classical fine-root vs coarse-root approach; (2) considering the specificity of root research to produce sound laboratory and field data; (3) describing typical, but overlooked steps for studying roots (e.g. root handling, cleaning and storage); and (4) gathering metadata necessary for the interpretation of results and their reuse. Most importantly, all root traits have been introduced with some degree of ecological context that will be a foundation for understanding their ecological meaning, their typical use and uncertainties, and some methodological and conceptual perspectives for future research. Considering all of this, we urge readers not to solely extract protocol recommendations for trait measurements from this work, but to take a moment to read and reflect on the extensive information contained in this broader guide to root ecology, including sections I-VII and the many introductions to each section and root trait description. Finally, it is critical to understand that a major aim of this guide is to help break down barriers between the many subdisciplines of root ecology and ecophysiology, broaden researchers' views on the multiple aspects of root study and create favourable conditions for the inception of comprehensive experiments on the role of roots in plant and ecosystem functioning.
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Affiliation(s)
- Grégoire T. Freschet
- CEFEUniv Montpellier, CNRS, EPHE, IRD1919 route de MendeMontpellier34293France
- Station d’Ecologie Théorique et ExpérimentaleCNRS2 route du CNRS09200MoulisFrance
| | - Loïc Pagès
- UR 1115 PSHCentre PACA, site AgroparcINRAE84914Avignon cedex 9France
| | - Colleen M. Iversen
- Environmental Sciences Division and Climate Change Science InstituteOak Ridge National LaboratoryOak RidgeTN37831USA
| | - Louise H. Comas
- USDA‐ARS Water Management Research Unit2150 Centre Avenue, Bldg D, Suite 320Fort CollinsCO80526USA
| | - Boris Rewald
- Department of Forest and Soil SciencesUniversity of Natural Resources and Life SciencesVienna1190Austria
| | - Catherine Roumet
- CEFEUniv Montpellier, CNRS, EPHE, IRD1919 route de MendeMontpellier34293France
| | - Jitka Klimešová
- Department of Functional EcologyInstitute of Botany CASDukelska 13537901TrebonCzech Republic
| | - Marcin Zadworny
- Institute of DendrologyPolish Academy of SciencesParkowa 562‐035KórnikPoland
| | - Hendrik Poorter
- Plant Sciences (IBG‐2)Forschungszentrum Jülich GmbHD‐52425JülichGermany
- Department of Biological SciencesMacquarie UniversityNorth RydeNSW2109Australia
| | | | - Thomas S. Adams
- Department of Plant SciencesThe Pennsylvania State UniversityUniversity ParkPA16802USA
| | - Agnieszka Bagniewska‐Zadworna
- Department of General BotanyInstitute of Experimental BiologyFaculty of BiologyAdam Mickiewicz UniversityUniwersytetu Poznańskiego 661-614PoznańPoland
| | - A. Glyn Bengough
- The James Hutton InstituteInvergowrie, Dundee,DD2 5DAUK
- School of Science and EngineeringUniversity of DundeeDundee,DD1 4HNUK
| | | | - Ivano Brunner
- Forest Soils and BiogeochemistrySwiss Federal Research Institute WSLZürcherstr. 1118903BirmensdorfSwitzerland
| | - Johannes H. C. Cornelissen
- Department of Ecological ScienceFaculty of ScienceVrije Universiteit AmsterdamDe Boelelaan 1085Amsterdam1081 HVthe Netherlands
| | - Eric Garnier
- CEFEUniv Montpellier, CNRS, EPHE, IRD1919 route de MendeMontpellier34293France
| | - Arthur Gessler
- Forest DynamicsSwiss Federal Research Institute WSLZürcherstr. 1118903BirmensdorfSwitzerland
- Institute of Terrestrial EcosystemsETH Zurich8092ZurichSwitzerland
| | - Sarah E. Hobbie
- Department of Ecology, Evolution and BehaviorUniversity of MinnesotaSt PaulMN55108USA
| | - Ina C. Meier
- Functional Forest EcologyUniversity of HamburgHaidkrugsweg 122885BarsbütelGermany
| | - Liesje Mommer
- Plant Ecology and Nature Conservation GroupDepartment of Environmental SciencesWageningen University and ResearchPO Box 476700 AAWageningenthe Netherlands
| | | | - Laura Rose
- Station d’Ecologie Théorique et ExpérimentaleCNRS2 route du CNRS09200MoulisFrance
- Senckenberg Biodiversity and Climate Research Centre (BiK-F)Senckenberganlage 2560325Frankfurt am MainGermany
| | - Peter Ryser
- Laurentian University935 Ramsey Lake RoadSudburyONP3E 2C6Canada
| | | | - Nadejda A. Soudzilovskaia
- Environmental Biology DepartmentInstitute of Environmental SciencesCMLLeiden UniversityLeiden2300 RAthe Netherlands
| | - Alexia Stokes
- INRAEAMAPCIRAD, IRDCNRSUniversity of MontpellierMontpellier34000France
| | - Tao Sun
- Institute of Applied EcologyChinese Academy of SciencesShenyang110016China
| | - Oscar J. Valverde‐Barrantes
- International Center for Tropical BotanyDepartment of Biological SciencesFlorida International UniversityMiamiFL33199USA
| | - Monique Weemstra
- CEFEUniv Montpellier, CNRS, EPHE, IRD1919 route de MendeMontpellier34293France
| | - Alexandra Weigelt
- Systematic Botany and Functional BiodiversityInstitute of BiologyLeipzig UniversityJohannisallee 21-23Leipzig04103Germany
| | - Nina Wurzburger
- Odum School of EcologyUniversity of Georgia140 E. Green StreetAthensGA30602USA
| | - Larry M. York
- Biosciences Division and Center for Bioenergy InnovationOak Ridge National LaboratoryOak RidgeTN37831USA
| | - Sarah A. Batterman
- School of Geography and Priestley International Centre for ClimateUniversity of LeedsLeedsLS2 9JTUK
- Cary Institute of Ecosystem StudiesMillbrookNY12545USA
| | - Moemy Gomes de Moraes
- Department of BotanyInstitute of Biological SciencesFederal University of Goiás1974690-900Goiânia, GoiásBrazil
| | - Štěpán Janeček
- School of Biological SciencesThe University of Western Australia35 Stirling HighwayCrawley (Perth)WA 6009Australia
| | - Hans Lambers
- School of Biological SciencesThe University of Western AustraliaCrawley (Perth)WAAustralia
| | - Verity Salmon
- Environmental Sciences Division and Climate Change Science InstituteOak Ridge National LaboratoryOak RidgeTN37831USA
| | - Nishanth Tharayil
- Department of Plant and Environmental SciencesClemson UniversityClemsonSC29634USA
| | - M. Luke McCormack
- Center for Tree ScienceMorton Arboretum, 4100 Illinois Rt. 53LisleIL60532USA
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16
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Freschet GT, Pagès L, Iversen CM, Comas LH, Rewald B, Roumet C, Klimešová J, Zadworny M, Poorter H, Postma JA, Adams TS, Bagniewska-Zadworna A, Bengough AG, Blancaflor EB, Brunner I, Cornelissen JHC, Garnier E, Gessler A, Hobbie SE, Meier IC, Mommer L, Picon-Cochard C, Rose L, Ryser P, Scherer-Lorenzen M, Soudzilovskaia NA, Stokes A, Sun T, Valverde-Barrantes OJ, Weemstra M, Weigelt A, Wurzburger N, York LM, Batterman SA, Gomes de Moraes M, Janeček Š, Lambers H, Salmon V, Tharayil N, McCormack ML. A starting guide to root ecology: strengthening ecological concepts and standardising root classification, sampling, processing and trait measurements. THE NEW PHYTOLOGIST 2021. [PMID: 34608637 DOI: 10.1111/nph.17572.hal-03379708] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
In the context of a recent massive increase in research on plant root functions and their impact on the environment, root ecologists currently face many important challenges to keep on generating cutting-edge, meaningful and integrated knowledge. Consideration of the below-ground components in plant and ecosystem studies has been consistently called for in recent decades, but methodology is disparate and sometimes inappropriate. This handbook, based on the collective effort of a large team of experts, will improve trait comparisons across studies and integration of information across databases by providing standardised methods and controlled vocabularies. It is meant to be used not only as starting point by students and scientists who desire working on below-ground ecosystems, but also by experts for consolidating and broadening their views on multiple aspects of root ecology. Beyond the classical compilation of measurement protocols, we have synthesised recommendations from the literature to provide key background knowledge useful for: (1) defining below-ground plant entities and giving keys for their meaningful dissection, classification and naming beyond the classical fine-root vs coarse-root approach; (2) considering the specificity of root research to produce sound laboratory and field data; (3) describing typical, but overlooked steps for studying roots (e.g. root handling, cleaning and storage); and (4) gathering metadata necessary for the interpretation of results and their reuse. Most importantly, all root traits have been introduced with some degree of ecological context that will be a foundation for understanding their ecological meaning, their typical use and uncertainties, and some methodological and conceptual perspectives for future research. Considering all of this, we urge readers not to solely extract protocol recommendations for trait measurements from this work, but to take a moment to read and reflect on the extensive information contained in this broader guide to root ecology, including sections I-VII and the many introductions to each section and root trait description. Finally, it is critical to understand that a major aim of this guide is to help break down barriers between the many subdisciplines of root ecology and ecophysiology, broaden researchers' views on the multiple aspects of root study and create favourable conditions for the inception of comprehensive experiments on the role of roots in plant and ecosystem functioning.
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Affiliation(s)
- Grégoire T Freschet
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, 1919 route de Mende, Montpellier, 34293, France
- Station d'Ecologie Théorique et Expérimentale, CNRS, 2 route du CNRS, 09200, Moulis, France
| | - Loïc Pagès
- UR 1115 PSH, Centre PACA, site Agroparc, INRAE, 84914, Avignon cedex 9, France
| | - Colleen M Iversen
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Louise H Comas
- USDA-ARS Water Management Research Unit, 2150 Centre Avenue, Bldg D, Suite 320, Fort Collins, CO, 80526, USA
| | - Boris Rewald
- Department of Forest and Soil Sciences, University of Natural Resources and Life Sciences, Vienna, 1190, Austria
| | - Catherine Roumet
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, 1919 route de Mende, Montpellier, 34293, France
| | - Jitka Klimešová
- Department of Functional Ecology, Institute of Botany CAS, Dukelska 135, 37901, Trebon, Czech Republic
| | - Marcin Zadworny
- Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035, Kórnik, Poland
| | - Hendrik Poorter
- Plant Sciences (IBG-2), Forschungszentrum Jülich GmbH, D-52425, Jülich, Germany
- Department of Biological Sciences, Macquarie University, North Ryde, NSW, 2109, Australia
| | - Johannes A Postma
- Plant Sciences (IBG-2), Forschungszentrum Jülich GmbH, D-52425, Jülich, Germany
| | - Thomas S Adams
- Department of Plant Sciences, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Agnieszka Bagniewska-Zadworna
- Department of General Botany, Institute of Experimental Biology, Faculty of Biology, Adam Mickiewicz University, Uniwersytetu Poznańskiego 6, 61-614, Poznań, Poland
| | - A Glyn Bengough
- The James Hutton Institute, Invergowrie, Dundee,, DD2 5DA, UK
- School of Science and Engineering, University of Dundee, Dundee,, DD1 4HN, UK
| | - Elison B Blancaflor
- Noble Research Institute, LLC, 2510 Sam Noble Parkway, Ardmore, OK, 73401, USA
| | - Ivano Brunner
- Forest Soils and Biogeochemistry, Swiss Federal Research Institute WSL, Zürcherstr. 111, 8903, Birmensdorf, Switzerland
| | - Johannes H C Cornelissen
- Department of Ecological Science, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, Amsterdam, 1081 HV, the Netherlands
| | - Eric Garnier
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, 1919 route de Mende, Montpellier, 34293, France
| | - Arthur Gessler
- Forest Dynamics, Swiss Federal Research Institute WSL, Zürcherstr. 111, 8903, Birmensdorf, Switzerland
- Institute of Terrestrial Ecosystems, ETH Zurich, 8092, Zurich, Switzerland
| | - Sarah E Hobbie
- Department of Ecology, Evolution and Behavior, University of Minnesota, St Paul, MN, 55108, USA
| | - Ina C Meier
- Functional Forest Ecology, University of Hamburg, Haidkrugsweg 1, 22885, Barsbütel, Germany
| | - Liesje Mommer
- Plant Ecology and Nature Conservation Group, Department of Environmental Sciences, Wageningen University and Research, PO Box 47, 6700 AA, Wageningen, the Netherlands
| | | | - Laura Rose
- Station d'Ecologie Théorique et Expérimentale, CNRS, 2 route du CNRS, 09200, Moulis, France
- Senckenberg Biodiversity and Climate Research Centre (BiK-F), Senckenberganlage 25, 60325, Frankfurt am Main, Germany
| | - Peter Ryser
- Laurentian University, 935 Ramsey Lake Road, Sudbury, ON, P3E 2C6, Canada
| | | | - Nadejda A Soudzilovskaia
- Environmental Biology Department, Institute of Environmental Sciences, CML, Leiden University, Leiden, 2300 RA, the Netherlands
| | - Alexia Stokes
- INRAE, AMAP, CIRAD, IRD, CNRS, University of Montpellier, Montpellier, 34000, France
| | - Tao Sun
- Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China
| | - Oscar J Valverde-Barrantes
- International Center for Tropical Botany, Department of Biological Sciences, Florida International University, Miami, FL, 33199, USA
| | - Monique Weemstra
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, 1919 route de Mende, Montpellier, 34293, France
| | - Alexandra Weigelt
- Systematic Botany and Functional Biodiversity, Institute of Biology, Leipzig University, Johannisallee 21-23, Leipzig, 04103, Germany
| | - Nina Wurzburger
- Odum School of Ecology, University of Georgia, 140 E. Green Street, Athens, GA, 30602, USA
| | - Larry M York
- Biosciences Division and Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Sarah A Batterman
- School of Geography and Priestley International Centre for Climate, University of Leeds, Leeds, LS2 9JT, UK
- Cary Institute of Ecosystem Studies, Millbrook, NY, 12545, USA
| | - Moemy Gomes de Moraes
- Department of Botany, Institute of Biological Sciences, Federal University of Goiás, 19, 74690-900, Goiânia, Goiás, Brazil
| | - Štěpán Janeček
- School of Biological Sciences, The University of Western Australia, 35 Stirling Highway, Crawley (Perth), WA 6009, Australia
| | - Hans Lambers
- School of Biological Sciences, The University of Western Australia, Crawley (Perth), WA, Australia
| | - Verity Salmon
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Nishanth Tharayil
- Department of Plant and Environmental Sciences, Clemson University, Clemson, SC, 29634, USA
| | - M Luke McCormack
- Center for Tree Science, Morton Arboretum, 4100 Illinois Rt. 53, Lisle, IL, 60532, USA
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17
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Taneda H, Ikeda T. Hydraulic architecture with high root-resistance fraction contributes to efficient carbon gain of plants in temperate habitats. AMERICAN JOURNAL OF BOTANY 2021; 108:1932-1945. [PMID: 34658016 DOI: 10.1002/ajb2.1753] [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: 12/18/2020] [Revised: 06/30/2021] [Accepted: 07/02/2021] [Indexed: 06/13/2023]
Abstract
PREMISE The hydraulic architecture in the leaves, stems and roots of plants constrains water transport and carbon gain through stomatal limitation to CO2 absorption. Because roots are the main bottleneck in water transport for a range of plant species, we assessed the ecophysiological mechanism and importance of a high fraction of root hydraulic resistance in woody and herbaceous species. METHODS Biomass partitioning and hydraulic conductance of leaves, stems, and roots of Japanese knotweed (Fallopia japonica, a perennial herb) and Japanese zelkova (Zelkova serrata, a deciduous tall tree) were measured. Theoretical analyses were used to examine whether the measured hydraulic architecture and biomass partitioning maximized the plant photosynthetic rate (the product of leaf area and photosynthetic rate per leaf area). RESULTS Root hydraulic resistance accounted for 83% and 68% of the total plant resistance for Japanese knotweed and Japanese zelkova, respectively. Comparisons of hydraulic and biomass partitioning revealed that high root-resistance fractions were attributable to low biomass partitioning to root organs rather than high mass-specific root conductance. The measured partitioning of hydraulic resistance closely corresponded to the predicted optimal partitioning, maximizing the plant photosynthetic rate for the two species. The high fraction of root resistance was predicted to be optimal with variations in air humidity and soil water potential. CONCLUSIONS These results suggest that the hydraulic architecture of plants growing in mesic and fertile habitats not only results in high root resistance due to small biomass partitioning to root organs, but contributes to efficient carbon gain.
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Affiliation(s)
- Haruhiko Taneda
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Bunkyo, Tokyo, 113-0033, Japan
| | - Takefumi Ikeda
- Department of Forest Science, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, 1-5 Shimogamohangi-cho, Sakyo, Kyoto, 606-8522, Japan
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18
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Bourbia I, Pritzkow C, Brodribb TJ. Herb and conifer roots show similar high sensitivity to water deficit. PLANT PHYSIOLOGY 2021; 186:1908-1918. [PMID: 34618104 PMCID: PMC8331161 DOI: 10.1093/plphys/kiab207] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 04/24/2021] [Indexed: 05/11/2023]
Abstract
Root systems play a major role in supplying the canopy with water, enabling photosynthesis and growth. Yet, much of the dynamic response of root hydraulics and its influence on gas exchange during soil drying and recovery remains uncertain. We examined the decline and recovery of the whole root hydraulic conductance (Kr) and canopy diffusive conductance (gc) during exposure to moderate water stress in two species with contrasting root systems: Tanacetum cinerariifolium (herbaceous Asteraceae) and Callitris rhomboidea (woody conifer). Optical dendrometers were used to record stem water potential at high temporal resolution and enabled non-invasive measurements of Kr calculated from the rapid relaxation kinetics of water potential in hydrating roots. We observed parallel declines in Kr and gc to <20% of unstressed levels during the early stages of water stress in both species. The recovery of Kr after rewatering differed between species. T. cinerariifolium recovered quickly, with 60% of Kr recovered within 2 h, while C. rhomboidea was much slower to return to its original Kr. Recovery of gc followed a similar trend to Kr in both species, with C. rhomboidea slower to recover. Our findings suggest that the pronounced sensitivity of Kr to drought is a common feature among different plant species, but recovery may vary depending on root type and water stress severity. Kr dynamics are proposed to modulate gc response during and following drought.
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Affiliation(s)
- Ibrahim Bourbia
- School of Natural Sciences, University of Tasmania, Hobart, TAS 7001, Australia
| | - Carola Pritzkow
- School of Natural Sciences, University of Tasmania, Hobart, TAS 7001, Australia
| | - Timothy J Brodribb
- School of Natural Sciences, University of Tasmania, Hobart, TAS 7001, Australia
- Author for communication:
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19
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Israel D, Khan S, Warren CR, Zwiazek JJ, Robson TM. The contribution of PIP2-type aquaporins to photosynthetic response to increased vapour pressure deficit. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:5066-5078. [PMID: 33928350 PMCID: PMC8219038 DOI: 10.1093/jxb/erab187] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 04/26/2021] [Indexed: 06/12/2023]
Abstract
The roles of different plasma membrane aquaporins (PIPs) in leaf-level gas exchange of Arabidopsis thaliana were examined using knockout mutants. Since multiple Arabidopsis PIPs are implicated in CO2 transport across cell membranes, we focused on identifying the effects of the knockout mutations on photosynthesis, and whether they are mediated through the control of stomatal conductance of water vapour (gs), mesophyll conductance of CO2 (gm), or both. We grew Arabidopsis plants in low and high humidity environments and found that the contribution of PIPs to gs was larger under low air humidity when the evaporative demand was high, whereas any effect of a lack of PIP function was minimal under higher humidity. The pip2;4 knockout mutant had 44% higher gs than wild-type plants under low humidity, which in turn resulted in an increased net photosynthetic rate (Anet). We also observed a 23% increase in whole-plant transpiration (E) for this knockout mutant. The lack of functional plasma membrane aquaporin AtPIP2;5 did not affect gs or E, but resulted in homeostasis of gm despite changes in humidity, indicating a possible role in regulating CO2 membrane permeability. CO2 transport measurements in yeast expressing AtPIP2;5 confirmed that this aquaporin is indeed permeable to CO2.
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Affiliation(s)
- David Israel
- Organismal and Evolutionary Biology (OEB), Viikki Plant Science Centre (ViPS), University of Helsinki, Finland
| | - Shanjida Khan
- Department of Renewable Resources, University of Alberta, Canada
| | - Charles R Warren
- School of Life and Environmental Sciences, University of Sydney, Australia
| | - Janusz J Zwiazek
- Department of Renewable Resources, University of Alberta, Canada
| | - T Matthew Robson
- Organismal and Evolutionary Biology (OEB), Viikki Plant Science Centre (ViPS), University of Helsinki, Finland
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20
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Sabir F, Zarrouk O, Noronha H, Loureiro-Dias MC, Soveral G, Gerós H, Prista C. Grapevine aquaporins: Diversity, cellular functions, and ecophysiological perspectives. Biochimie 2021; 188:61-76. [PMID: 34139292 DOI: 10.1016/j.biochi.2021.06.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 05/23/2021] [Accepted: 06/07/2021] [Indexed: 11/30/2022]
Abstract
High-scored premium wines are typically produced under moderate drought stress, suggesting that the water status of grapevine is crucial for wine quality. Aquaporins greatly influence the plant water status by facilitating water diffusion across the plasma membrane in a tightly regulated manner. They adjust the hydraulic conductance of the plasma membrane rapidly and reversibly, which is essential in specific physiological events, including adaptation to soil water scarcity. The comprehension of the sophisticated plant-water relations at the molecular level are thus important to optimize agricultural practices or to assist plant breeding programs. This review explores the recent progresses in understanding the water transport in grapevine at the cellular level through aquaporins and its regulation. Important aspects, including aquaporin structure, diversity, cellular localization, transport properties, and regulation at the cellular and whole plant level are addressed. An ecophysiological perspective about the roles of grapevine aquaporins in plant response to drought stress is also provided.
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Affiliation(s)
- Farzana Sabir
- Linking Landscape, Environment, Agriculture and Food (LEAF), Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017, Lisbon, Portugal; Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, 1649-003, Lisbon, Portugal.
| | - Olfa Zarrouk
- Association SFCOLAB - Collaborative Laboratory for Digital Innovation in Agriculture, Rua Cândido dos Reis nº1, Espaço SFCOLAB, 2560-312, Torres Vedras, Portugal
| | - Henrique Noronha
- Centre of Molecular and Environmental Biology (CBMA), Department of Biology, University of Minho, 4710-057, Braga, Portugal; Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes e Alto Douro, 5001-801, Vila Real, Portugal
| | - Maria C Loureiro-Dias
- Linking Landscape, Environment, Agriculture and Food (LEAF), Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017, Lisbon, Portugal
| | - Graça Soveral
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, 1649-003, Lisbon, Portugal
| | - Hernâni Gerós
- Centre of Molecular and Environmental Biology (CBMA), Department of Biology, University of Minho, 4710-057, Braga, Portugal; Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes e Alto Douro, 5001-801, Vila Real, Portugal; Centre of Biological Engineering (CEB), Department of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal
| | - Catarina Prista
- Linking Landscape, Environment, Agriculture and Food (LEAF), Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017, Lisbon, Portugal; Departamento de Recursos Biologicos, Ambiente e Territorio (DRAT), Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017, Lisbon, Portugal
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21
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Reingwirtz I, Uretsky J, Cuneo IF, Knipfer T, Reyes C, Walker MA, McElrone AJ. Inherent and Stress-Induced Responses of Fine Root Morphology and Anatomy in Commercial Grapevine Rootstocks with Contrasting Drought Resistance. PLANTS (BASEL, SWITZERLAND) 2021; 10:1121. [PMID: 34205907 PMCID: PMC8227383 DOI: 10.3390/plants10061121] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/24/2021] [Accepted: 05/24/2021] [Indexed: 11/16/2022]
Abstract
Some grapevine rootstocks perform better than others during and after drought events, yet it is not clear how inherent and stress-induced differences in root morphology and anatomy along the length of fine roots are involved in these responses. Using a variety of growing conditions and plant materials, we observed significant differences in root diameter, specific root length (SRL) and root diameter distribution between two commonly used commercial grapevine rootstocks: Richter 110 (110R; drought resistant) and Millardet et de Grasset 101-14 (101-14Mgt; drought sensitive). The 110R consistently showed greater root diameters with smaller SRL and proportion of root length comprised of fine lateral roots. The 110R also exhibited significantly greater distance from tip to nearest lateral, longer white root length, and larger proportion of root length that is white under drought stress. Mapping of fine root cortical lacunae showed similar patterns between the rootstocks; mechanical failure of cortical cells was common in the maturation zone, limited near the root tip, and increased with drought stress for both genotypes; however, lacuna formed under wetter soil conditions in 110R. Results suggest that drought resistance in grapevine rootstocks is associated with thick, limitedly branched roots with a larger proportion of white-functional roots that tend to form lacuna under more mild water deficit, all of which likely favor continued resource acquisition at depth.
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Affiliation(s)
- Idan Reingwirtz
- Department of Viticulture and Enology, University of California, Davis, CA 95616, USA; (I.R.); (J.U.); (C.R.); (M.A.W.)
| | - Jake Uretsky
- Department of Viticulture and Enology, University of California, Davis, CA 95616, USA; (I.R.); (J.U.); (C.R.); (M.A.W.)
| | - Italo F. Cuneo
- Faculty of Agriculture and Food Sciences, Pontificia Universidad Católica de Valparaíso, Valparaíso 2340025, Chile;
| | - Thorsten Knipfer
- Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada;
| | - Clarissa Reyes
- Department of Viticulture and Enology, University of California, Davis, CA 95616, USA; (I.R.); (J.U.); (C.R.); (M.A.W.)
| | - M. Andrew Walker
- Department of Viticulture and Enology, University of California, Davis, CA 95616, USA; (I.R.); (J.U.); (C.R.); (M.A.W.)
| | - Andrew J. McElrone
- Department of Viticulture and Enology, University of California, Davis, CA 95616, USA; (I.R.); (J.U.); (C.R.); (M.A.W.)
- Crops Pathology and Genetics Research Unit, United States Department of Agriculture, Agricultural Research Service, Davis, CA 95616, USA
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22
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Domec JC, King JS, Carmichael MJ, Overby AT, Wortemann R, Smith WK, Miao G, Noormets A, Johnson DM. Aquaporins, and not changes in root structure, provide new insights into physiological responses to drought, flooding, and salinity. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:4489-4501. [PMID: 33677600 DOI: 10.1093/jxb/erab100] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 02/27/2021] [Indexed: 06/12/2023]
Abstract
The influence of aquaporin (AQP) activity on plant water movement remains unclear, especially in plants subject to unfavorable conditions. We applied a multitiered approach at a range of plant scales to (i) characterize the resistances controlling water transport under drought, flooding, and flooding plus salinity conditions; (ii) quantify the respective effects of AQP activity and xylem structure on root (Kroot), stem (Kstem), and leaf (Kleaf) conductances; and (iii) evaluate the impact of AQP-regulated transport capacity on gas exchange. We found that drought, flooding, and flooding plus salinity reduced Kroot and root AQP activity in Pinus taeda, whereas Kroot of the flood-tolerant Taxodium distichum did not decline under flooding. The extent of the AQP control of transport efficiency varied among organs and species, ranging from 35-55% in Kroot to 10-30% in Kstem and Kleaf. In response to treatments, AQP-mediated inhibition of Kroot rather than changes in xylem acclimation controlled the fluctuations in Kroot. The reduction in stomatal conductance and its sensitivity to vapor pressure deficit were direct responses to decreased whole-plant conductance triggered by lower Kroot and larger resistance belowground. Our results provide new mechanistic and functional insights on plant hydraulics that are essential to quantifying the influences of future stress on ecosystem function.
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Affiliation(s)
- Jean-Christophe Domec
- Bordeaux Sciences AGRO, UMR1391 ISPA INRA, 1 Cours du général de Gaulle, 33175 Gradignan Cedex, France
- Nicholas School of the Environment, Duke University, Durham, NC 27708, USA
| | - John S King
- Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, NC 27606, USA
| | - Mary J Carmichael
- Departments of Biology and Environmental Studies, Hollins University, Roanoke, VA 24020, USA
| | - Anna Treado Overby
- Planning, Design and the Built Environment, Clemson University, Clemson, SC 29634, USA
| | - Remi Wortemann
- Université de Lorraine, INRA, UMR 1434 Silva, 54000, Nancy, France
| | - William K Smith
- Department of Biology, Wake Forest University, Winston-Salem, NC 27109, USA
| | - Guofang Miao
- School of Geographical Sciences, Fujian Normal University, Fuzhou, FJ-350007, PR China
| | - Asko Noormets
- Department of Ecology and Conservation Biology, Texas A&M University, College Station, TX 77843, USA
| | - Daniel M Johnson
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA
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23
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Cuneo IF, Barrios-Masias F, Knipfer T, Uretsky J, Reyes C, Lenain P, Brodersen CR, Walker MA, McElrone AJ. Differences in grapevine rootstock sensitivity and recovery from drought are linked to fine root cortical lacunae and root tip function. THE NEW PHYTOLOGIST 2021; 229:272-283. [PMID: 32171020 DOI: 10.1111/nph.16542] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 03/05/2020] [Indexed: 06/10/2023]
Abstract
Structural changes during severe drought stress greatly modify the hydraulic properties of fine roots. Yet, the physiological basis behind the restoration of fine root water uptake capacity during water recovery remains unknown. Using neutron radiography (NR), X-ray micro-computed tomography (micro-CT), fluorescence microscopy, and fine root hydraulic conductivity measurements (Lpr ), we examined how drought-induced changes in anatomy and hydraulic properties of contrasting grapevine rootstocks are coupled with fine root growth dynamics during drought and return of soil moisture. Lacunae formation in drought-stressed fine roots was associated with a significant decrease in fine root Lpr for both rootstocks. However, lacunae formation occurred under milder stress in the drought-resistant rootstock, 110R. Suberin was deposited at an earlier developmental stage in fine roots of 101-14Mgt (i.e. drought susceptible), probably limiting cortical lacunae formation during mild stress. During recovery, we found that only 110R fine roots showed rapid re-establishment of elongation and water uptake capacity and we found that soil water status surrounding root tips differed between rootstocks as imaged with NR. These data suggest that drought resistance in grapevine rootstocks is associated with rapid re-establishment of growth and Lpr near the root tip upon re-watering by limiting competing sites along the root cylinder.
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Affiliation(s)
- Italo F Cuneo
- Department of Agriculture and Food Sciences, Pontificia Universidad Católica de Valparaíso, Valparaíso, 2340025, Chile
| | - Felipe Barrios-Masias
- Department of Agriculture, Veterinary and Rangeland Sciences, University of Nevada, Reno, Reno, NV, 89557, USA
| | - Thorsten Knipfer
- Department of Viticulture and Enology, University of California, Davis, CA, 95618, USA
| | - Jake Uretsky
- Department of Viticulture and Enology, University of California, Davis, CA, 95618, USA
| | - Clarissa Reyes
- Department of Viticulture and Enology, University of California, Davis, CA, 95618, USA
| | - Pierre Lenain
- Department of Viticulture and Enology, University of California, Davis, CA, 95618, USA
| | - Craig R Brodersen
- School of Forestry and Environmental Studies, Yale University, New Haven, CT, 06511, USA
| | - M Andrew Walker
- Department of Viticulture and Enology, University of California, Davis, CA, 95618, 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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24
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Versatile Roles of Aquaporins in Plant Growth and Development. Int J Mol Sci 2020; 21:ijms21249485. [PMID: 33322217 PMCID: PMC7763978 DOI: 10.3390/ijms21249485] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 12/07/2020] [Accepted: 12/10/2020] [Indexed: 12/14/2022] Open
Abstract
Aquaporins (AQPs) are universal membrane integrated water channel proteins that selectively and reversibly facilitate the movement of water, gases, metalloids, and other small neutral solutes across cellular membranes in living organisms. Compared with other organisms, plants have the largest number of AQP members with diverse characteristics, subcellular localizations and substrate permeabilities. AQPs play important roles in plant water relations, cell turgor pressure maintenance, the hydraulic regulation of roots and leaves, and in leaf transpiration, root water uptake, and plant responses to multiple biotic and abiotic stresses. They are also required for plant growth and development. In this review, we comprehensively summarize the expression and roles of diverse AQPs in the growth and development of various vegetative and reproductive organs in plants. The functions of AQPs in the intracellular translocation of hydrogen peroxide are also discussed.
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25
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Zhang L, Merlin I, Pascal S, Bert P, Domergue F, Gambetta GA. Drought activates MYB41 orthologs and induces suberization of grapevine fine roots. PLANT DIRECT 2020; 4:e00278. [PMID: 33251473 PMCID: PMC7680640 DOI: 10.1002/pld3.278] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 09/26/2020] [Accepted: 09/28/2020] [Indexed: 05/07/2023]
Abstract
The permeability of roots to water and nutrients is controlled through a variety of mechanisms and one of the most conspicuous is the presence of the Casparian strips and suberin lamellae. Roots actively regulate the creation of these structures developmentally, along the length of the root, and in response to the environment, including drought. In the current study, we characterized the suberin composition along the length of grapevine fine roots during development and in response to water deficit, and in the same root systems we quantified changes in expression of suberin biosynthesis- and deposition-related gene families (via RNAseq) allowing the identification of drought-responsive suberin-related genes. Grapevine suberin composition did not differ between primary and lateral roots, and was similar to that of other species. Under water deficit there was a global upregulation of suberin biosynthesis which resulted in an increase of suberin specific monomers, but without changes in their relative abundances, and this upregulation took place across all the developmental stages of fine roots. These changes corresponded to the upregulation of numerous suberin biosynthesis- and export-related genes which included orthologs of the previously characterized AtMYB41 transcriptional factor. Functional validation of two grapevine MYB41 orthologs, VriMYB41 and VriMYB41-like, confirmed their ability to globally upregulate suberin biosynthesis, export, and deposition. This study provides a detailed characterization of the developmental and water deficit induced suberization of grapevine fine roots and identifies important orthologs responsible for suberin biosynthesis, export, and its regulation in grape.
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Affiliation(s)
- Li Zhang
- EGFVBordeaux‐Sciences AgroINRAUniv. BordeauxISVVVillenave d'OrnonFrance
| | - Isabelle Merlin
- EGFVBordeaux‐Sciences AgroINRAUniv. BordeauxISVVVillenave d'OrnonFrance
| | - Stéphanie Pascal
- Laboratoire de Biogenèse MembranaireCNRS – Univ. Bordeaux ‐ UMR 5200Bâtiment A3 ‐ INRA Bordeaux AquitaineVillenave d'OrnonFrance
| | | | - Frédéric Domergue
- Laboratoire de Biogenèse MembranaireCNRS – Univ. Bordeaux ‐ UMR 5200Bâtiment A3 ‐ INRA Bordeaux AquitaineVillenave d'OrnonFrance
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26
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Dayer S, Herrera JC, Dai Z, Burlett R, Lamarque LJ, Delzon S, Bortolami G, Cochard H, Gambetta GA. The sequence and thresholds of leaf hydraulic traits underlying grapevine varietal differences in drought tolerance. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:4333-4344. [PMID: 32279077 PMCID: PMC7337184 DOI: 10.1093/jxb/eraa186] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 04/10/2020] [Indexed: 05/20/2023]
Abstract
Adapting agriculture to climate change is driving the need for the selection and breeding of drought-tolerant crops. The aim of this study was to identify key drought tolerance traits and determine the sequence of their water potential thresholds across three grapevine cultivars with contrasting water use behaviors, Grenache, Syrah, and Semillon. We quantified differences in water use between cultivars and combined this with the determination of other leaf-level traits (e.g. leaf turgor loss point, π TLP), leaf vulnerability to embolism (P50), and the hydraulic safety margin (HSM P50). Semillon exhibited the highest maximum transpiration (Emax), and lowest sensitivity of canopy stomatal conductance (Gc) to vapor pressure deficit (VPD), followed by Syrah and Grenache. Increasing Emax was correlated with more negative water potential at which stomata close (Pgs90), π TLP, and P50, suggesting that increasing water use is associated with hydraulic traits allowing gas exchange under more negative water potentials. Nevertheless, all the cultivars closed their stomata prior to leaf embolism formation. Modeling simulations demonstrated that despite a narrower HSM, Grenache takes longer to reach thresholds of hydraulic failure due to its conservative water use. This study demonstrates that the relationships between leaf hydraulic traits are complex and interactive, stressing the importance of integrating multiple traits in characterizing drought tolerance.
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Affiliation(s)
- Silvina Dayer
- EGFV, Bordeaux-Sciences Agro, INRA, Université de Bordeaux, ISVV, Villenave d’Ornon, France
- Correspondence:
| | - José Carlos Herrera
- Institute of Viticulture and Pomology, University of Natural Resources and Life Sciences (BOKU), Tulln, Austria
| | - Zhanwu Dai
- Beijing Key Laboratory of Grape Science and Enology and Key Laboratory of Plant Resources, Institute of Botany, the Chinese Academy of Sciences, Beijing, China
| | - Régis Burlett
- Biodiversité Gènes et Communautés, Institut National de la Recherche Agronomique (INRA), Université Bordeaux, Cestas, France
| | - Laurent J Lamarque
- Biodiversité Gènes et Communautés, Institut National de la Recherche Agronomique (INRA), Université Bordeaux, Cestas, France
| | - Sylvain Delzon
- Biodiversité Gènes et Communautés, Institut National de la Recherche Agronomique (INRA), Université Bordeaux, Cestas, France
| | | | - Hervé Cochard
- Université Clermont-Auvergne, INRA, PIAF, Clermont-Ferrand, France
| | - Gregory A Gambetta
- EGFV, Bordeaux-Sciences Agro, INRA, Université de Bordeaux, ISVV, Villenave d’Ornon, France
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27
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Gal A, Hendel E, Peleg Z, Schwartz N, Sade N. Measuring the Hydraulic Conductivity of Grass Root Systems. ACTA ACUST UNITED AC 2020; 5:e20110. [PMID: 32311238 DOI: 10.1002/cppb.20110] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Root-system hydraulic conductivity (RSHC) is an important physiological characteristic that describes the inherent ability of roots to conduct water across a water-potential gradient between the root and the stem xylem. RSHC is commonly used as an indicator of plant functioning and adaptability to a given environment. A simple, fast, and easy-to-use protocol is described for the quantification of RSHC at the seedling stage in two important monocot species grown in hydroponic solution: Setaria viridis, a C4 model plant, and wheat, a C3 crop plant. This protocol can also be easily modified for use with almost any grass species and environmental treatments, such as salinity or hormone treatments. © 2020 by John Wiley & Sons, Inc. Basic Protocol: Setaria hydrostatic root-system hydraulic conductivity Alternate Protocol: Measuring the root conductivity of young plants with soft stems.
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Affiliation(s)
- Atara Gal
- School of Plant Science and Food Security, Tel Aviv University, Tel Aviv, Israel
| | - Elisha Hendel
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, Israel.,Department of Soil and Water Sciences, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Zvi Peleg
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Nimrod Schwartz
- Department of Soil and Water Sciences, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Nir Sade
- School of Plant Science and Food Security, Tel Aviv University, Tel Aviv, Israel
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28
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Buoso S, Pagliari L, Musetti R, Fornasier F, Martini M, Loschi A, Fontanella MC, Ermacora P. With or Without You: Altered Plant Response to Boron-Deficiency in Hydroponically Grown Grapevines Infected by Grapevine Pinot Gris Virus Suggests a Relation Between Grapevine Leaf Mottling and Deformation Symptom Occurrence and Boron Plant Availability. FRONTIERS IN PLANT SCIENCE 2020; 11:226. [PMID: 32194603 PMCID: PMC7062799 DOI: 10.3389/fpls.2020.00226] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 02/13/2020] [Indexed: 06/10/2023]
Abstract
Despite the increasing spread of Grapevine Leaf Mottling and Deformation (GLMD) worldwide, little is known about its etiology. After identification of grapevine Pinot gris virus (GPGV) as the presumptive causal agent of the disease in 2015, various publications have evaluated GPGV involvement in GLMD. Nevertheless, there are only partial clues to explain the presence of GPGV in both symptomatic and asymptomatic grapevines and the mechanisms that trigger symptom development, and so a consideration of new factors is required. Given the similarities between GLMD and boron (B)-deficiency symptoms in grapevine plants, we posited that GPGV interferes in B homeostasis. By using a hydroponic system to control B availability, we investigated the effects of different B supplies on grapevine phenotype and those of GPGV infection on B acquisition and translocation machinery, by means of microscopy, ionomic and gene expression analyses in both roots and leaves. The transcription of the genes regulating B homeostasis was unaffected by the presence of GPGV alone, but was severely altered in plants exposed to both GPGV infection and B-deficiency, allowing us to speculate that the capricious and patchy occurrence of GLMD symptoms in the field may not be related solely to GPGV, but to GPGV interference in plant responses to different B availabilities. This hypothesis found preliminary positive confirmations in analyses on field-grown plants.
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Affiliation(s)
- Sara Buoso
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Udine, Italy
| | - Laura Pagliari
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Udine, Italy
| | - Rita Musetti
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Udine, Italy
| | - Flavio Fornasier
- CREA Research Centre for Viticulture and Enology, Gorizia, Italy
| | - Marta Martini
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Udine, Italy
| | - Alberto Loschi
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Udine, Italy
| | - Maria Chiara Fontanella
- Department for Sustainable Process, Agricultural Faculty, Università Cattolica del Sacro Cuore, Piacenza, Italy
| | - Paolo Ermacora
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Udine, Italy
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Xu H, Zwiazek JJ. Fungal Aquaporins in Ectomycorrhizal Root Water Transport. FRONTIERS IN PLANT SCIENCE 2020; 11:302. [PMID: 32265956 PMCID: PMC7103631 DOI: 10.3389/fpls.2020.00302] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 03/02/2020] [Indexed: 05/20/2023]
Abstract
Ectomycorrhizal fungi influence root water transport of host plants. To delineate the exact mechanisms of how fungal partner alters root water relations, it is important to understand the functions of fungal transmembrane water channels, i.e., aquaporins, the key component in the symplastic pathways. In this paper, we discussed what roles the fungal aquaporins may play in root water transport. We also highlighted the opportunities of using integrated approaches to address rising questions in future hotspots of aquaporin and root water relations research.
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Affiliation(s)
- Hao Xu
- Summerland Research and Development Centre, Agriculture and Agri-Food Canada, Summerland, BC, Canada
- *Correspondence: Hao Xu,
| | - Janusz J. Zwiazek
- Department of Renewable Resources, University of Alberta, Edmonton, AB, Canada
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Rodriguez-Dominguez CM, Brodribb TJ. Declining root water transport drives stomatal closure in olive under moderate water stress. THE NEW PHYTOLOGIST 2020; 225:126-134. [PMID: 31498457 DOI: 10.1111/nph.16177] [Citation(s) in RCA: 74] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 09/01/2019] [Indexed: 05/24/2023]
Abstract
Efficient water transport from soil to leaves sustains stomatal opening and steady-state photosynthesis. The aboveground portion of this pathway is well-described, yet the roots and their connection with the soil are still poorly understood due to technical limitations. Here we used a novel rehydration technique to investigate changes in the hydraulic pathway between roots and soil and within the plant body as individual olive plants were subjected to a range of water stresses. Whole root hydraulic resistance (including the radial pathway from xylem to the soil-root interface) constituted 81% of the whole-plant resistance in unstressed plants, increasing to > 95% under a moderate level of water stress. The decline in this whole root hydraulic conductance occurred in parallel with stomatal closure and contributed significantly to the reduction in canopy conductance according to a hydraulic model. Our results demonstrate that losses in root hydraulic conductance, mainly due to a disconnection from the soil during moderate water stress in olive plants, are profound and sufficient to induce stomatal closure before cavitation occurs. Future studies will determine whether this core regulatory role of root hydraulics exists more generally among diverse plant species.
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Affiliation(s)
- Celia M Rodriguez-Dominguez
- Irrigation and Crop Ecophysiology Group, Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS, CSIC), Avenida Reina Mercedes, 10, 41012, Sevilla, Spain
- School of Biological Sciences, University of Tasmania, Private Bag 55, Hobart, TAS, 7001, Australia
| | - Timothy J Brodribb
- School of Biological Sciences, University of Tasmania, Private Bag 55, Hobart, TAS, 7001, Australia
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Armand T, Cullen M, Boiziot F, Li L, Fricke W. Cortex cell hydraulic conductivity, endodermal apoplastic barriers and root hydraulics change in barley (Hordeum vulgare L.) in response to a low supply of N and P. ANNALS OF BOTANY 2019; 124:1091-1107. [PMID: 31309230 PMCID: PMC7145705 DOI: 10.1093/aob/mcz113] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 06/28/2019] [Indexed: 05/09/2023]
Abstract
BACKGROUND Mineral nutrient limitation affects the water flow through plants. We wanted to test on barley whether any change in root-to-shoot ratio in response to low supply of nitrogen and phosphate is accompanied by changes in root and cell hydraulic properties and involves changes in aquaporin (AQP) gene expression and root apoplastic barriers (suberin lamellae, Casparian bands). METHODS Plants were grown hydroponically on complete nutrient solution or on solution containing only 3.3 % or 2.5 % of the control level of nutrient. Plants were analysed when they were 14-18 d old. RESULTS Nutrient-limited plants adjusted water flow to an increased root-to-shoot surface area ratio through a reduction in root hydraulic conductivity (Lp) as determined through exudation analyses. Cortex cell Lp (cell pressure probe analyses) decreased in the immature but not the mature region of the main axis of seminal roots and in primary lateral roots. The aquaporin inhibitor HgCl2 reduced root Lp most in nutrient-sufficient control plants. Exchange of low-nutrient for control media caused a rapid (20-80 min) and partial recovery in Lp, though cortex cell Lp did not increase in any of the root regions analysed. The gene expression level (qPCR analyses) of five plasma membrane-localized AQP isoforms did not change in bulk root extracts, while the formation of apoplastic barriers increased considerably along the main axis of root and lateral roots in low-nutrient treatments. CONCLUSIONS Decrease in root and cortex cell Lp enables the adjustment of root water uptake to increased root-to-shoot area ratio in nutrient-limited plants. Aquaporins are the prime candidate to play a key role in this response. Modelling of water flow suggests that some of the reduction in root Lp is due to increased formation of apoplastic barriers.
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Affiliation(s)
- Thomas Armand
- School of Biology and Environmental Sciences, University College Dublin, Belfield, Dublin, Republic of Ireland
| | - Michelle Cullen
- School of Biology and Environmental Sciences, University College Dublin, Belfield, Dublin, Republic of Ireland
| | - Florentin Boiziot
- School of Biology and Environmental Sciences, University College Dublin, Belfield, Dublin, Republic of Ireland
| | - Lingyu Li
- School of Biology and Environmental Sciences, University College Dublin, Belfield, Dublin, Republic of Ireland
- College of Life Sciences, Shanxi Agricultural University, Taigu, China
| | - Wieland Fricke
- School of Biology and Environmental Sciences, University College Dublin, Belfield, Dublin, Republic of Ireland
- For correspondence. E-mail
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Anisimov AV, Dautova NR, Suslov MA. Growth function and intercellular water transfer in excised roots. PROTOPLASMA 2019; 256:1425-1432. [PMID: 31134406 DOI: 10.1007/s00709-019-01388-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 04/24/2019] [Indexed: 06/09/2023]
Abstract
On the example of maize seedling roots, it was shown that segments of the root suction zone excised from intact mother seedlings maintain the function of elongation growth and are able to regulate water transfer. Using the gradient NMR method, the effective intercellular permeability of root suction zone segments was shown to reduce with respect to intact seedling roots. The segment fragmentation into smaller pieces 3 mm long resulted in the permeability decrease by 60%. The reduction is associated with the cell defensive response to water loss through cuts and blocking of the additive water transfer along the segment length, resulting from segment cutting.
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Affiliation(s)
- A V Anisimov
- FRC Kazan Scientific Center, Russian Academy of Sciences, Kazan Institute of Biochemistry and Biophysics, Lobachevskogo 2/31 st, P.O. Box 30, Kazan, 420111, Russia
| | - N R Dautova
- FRC Kazan Scientific Center, Russian Academy of Sciences, Kazan Institute of Biochemistry and Biophysics, Lobachevskogo 2/31 st, P.O. Box 30, Kazan, 420111, Russia
| | - Maksim A Suslov
- FRC Kazan Scientific Center, Russian Academy of Sciences, Kazan Institute of Biochemistry and Biophysics, Lobachevskogo 2/31 st, P.O. Box 30, Kazan, 420111, Russia.
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Wang H, Wang Z, Dong X. Anatomical structures of fine roots of 91 vascular plant species from four groups in a temperate forest in Northeast China. PLoS One 2019; 14:e0215126. [PMID: 31042717 PMCID: PMC6494041 DOI: 10.1371/journal.pone.0215126] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2017] [Accepted: 03/28/2019] [Indexed: 11/19/2022] Open
Abstract
Fine roots of plants play an important role in terrestrial ecosystems. There is a close association between the anatomical characteristics and physiological and ecological functions of plants, but we still have a very limited knowledge of anatomical traits. For example, (1) we do not know if herbs and grasses have anatomical patterns similar to those of woody plants, and (2) the variation among different woody plants in the same ecosystem is unclear. In the present study, we analysed the anatomical structures of the fine root systems of various groups of vascular plants (ferns, eudicot herbs, monocots and woody plants) from the same ecosystem (a natural secondary forest on Mao'er Mountain, Heilongjiang, China) to answer the following questions: (1) How does the anatomy of the fine roots change with root order in various plant groups in the same ecosystem? (2) What is the pattern of variation within group? The results show that anatomical traits can be divided into 3 categories: traits that indicate the root capacity to transport resource along the root (stele diameter, xylem cell diameter and xylem cell area); traits that indicate absorptive capacity cortical thickness, (the number of cortical cell layers and the diameter of cortical cells); and traits that are integrated indicators (diameter and the stele to root diameter ratio). The traits indicate the root capacity to transport resource along the root order is generally similar among groups, but absorptive capacity is very different. The shift in function is the main factor influencing the fine root anatomy. Some traits show large variation within groups, but the variations in other traits are small. The traits indicate that the lower-order roots (absorbing roots) in distinct groups are of the first one or two root order in ferns, the first two or three orders in eudicot herbs, the first (only two root orders) or first two orders (more than three root orders) in monocots and the first four or five root orders in woody plants and the other roots are higher-order roots (transport roots). The result will helpful to understand the similarities and differences among groups and the physiological and ecological functions of plant roots.
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Affiliation(s)
- Hongfeng Wang
- School of Forestry, Northeast Forestry University, Harbin, China
| | - Zhengquan Wang
- School of Forestry, Northeast Forestry University, Harbin, China
| | - Xueyun Dong
- School of Science, Harbin University, Harbin, China
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Khadka VS, Vaughn K, Xie J, Swaminathan P, Ma Q, Cramer GR, Fennell AY. Transcriptomic response is more sensitive to water deficit in shoots than roots of Vitis riparia (Michx.). BMC PLANT BIOLOGY 2019; 19:72. [PMID: 30760212 PMCID: PMC6375209 DOI: 10.1186/s12870-019-1664-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 01/28/2019] [Indexed: 05/11/2023]
Abstract
BACKGROUND Drought is an important constraint on grapevine sustainability. Vitis riparia, widely used in rootstock and scion breeding, has been studied in isolated leaf drying response studies; however, it is essential to identify key root and shoot water deficit signaling traits in intact plants. This information will aid improved scion and rootstock selection and management practices in grapevine. RNAseq data were generated from V. riparia roots and shoots under water deficit and well-watered conditions to determine root signaling and shoot responses to water deficit. RESULTS Shoot elongation, photosynthetic rate, and stomatal conductance were significantly reduced in water deficit (WD) treated than in well-watered grapevines. RNAseq analysis indicated greater transcriptional differences in shoots than in roots under WD, with 6925 and 1395 genes differentially expressed, respectively (q-value < 0.05). There were 50 and 25 VitisNet pathways significantly enriched in WD relative to well-watered treatments in grapevine shoots and roots, respectively. The ABA biosynthesis genes beta-carotene hydroxylase, zeaxanthin epoxidase, and 9-cis-epoxycarotenoid dioxygenases were up-regulated in WD root and WD shoot. A positive enrichment of ABA biosynthesis genes and signaling pathways in WD grapevine roots indicated enhanced root signaling to the shoot. An increased frequency of differentially expressed reactive oxygen species scavenging (ROS) genes were found in the WD shoot. Analyses of hormone signaling genes indicated a strong ABA, auxin, and ethylene network and an ABA, cytokinin, and circadian rhythm network in both WD shoot and WD root. CONCLUSIONS This work supports previous findings in detached leaf studies suggesting ABA-responsive binding factor 2 (ABF2) is a central regulator in ABA signaling in the WD shoot. Likewise, ABF2 may have a key role in V. riparia WD shoot and WD root. A role for ABF3 was indicated only in WD root. WD shoot and WD root hormone expression analysis identified strong ABA, auxin, ethylene, cytokinin, and circadian rhythm signaling networks. These results present the first ABA, cytokinin, and circadian rhythm signaling network in roots under water deficit. These networks point to organ specific regulators that should be explored to further define the communication network from soil to shoot.
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Affiliation(s)
- Vedbar Singh Khadka
- McFadden BioStress Laboratory, Agronomy, Horticulture, and Plant Science Department, South Dakota State University, Brookings, SD 57006 USA
- JABSOM Bioinformatics Core, Department of Complementary & Integrative Medicine, University of Hawaii, Honolulu, HI USA
| | - Kimberley Vaughn
- McFadden BioStress Laboratory, Agronomy, Horticulture, and Plant Science Department, South Dakota State University, Brookings, SD 57006 USA
| | - Juan Xie
- McFadden BioStress Laboratory, Agronomy, Horticulture, and Plant Science Department, South Dakota State University, Brookings, SD 57006 USA
- South Dakota State University, Brookings, SD 57006 USA
| | - Padmapriya Swaminathan
- McFadden BioStress Laboratory, Agronomy, Horticulture, and Plant Science Department, South Dakota State University, Brookings, SD 57006 USA
- South Dakota State University, Brookings, SD 57006 USA
| | - Qin Ma
- McFadden BioStress Laboratory, Agronomy, Horticulture, and Plant Science Department, South Dakota State University, Brookings, SD 57006 USA
- South Dakota State University, Brookings, SD 57006 USA
| | - Grant R. Cramer
- Department of Biochemistry and Molecular Biology, University of Nevada, Reno, NV USA
| | - Anne Y. Fennell
- McFadden BioStress Laboratory, Agronomy, Horticulture, and Plant Science Department, South Dakota State University, Brookings, SD 57006 USA
- South Dakota State University, Brookings, SD 57006 USA
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Rodríguez-Gamir J, Xue J, Clearwater MJ, Meason DF, Clinton PW, Domec JC. Aquaporin regulation in roots controls plant hydraulic conductance, stomatal conductance, and leaf water potential in Pinus radiata under water stress. PLANT, CELL & ENVIRONMENT 2019; 42:717-729. [PMID: 30307040 DOI: 10.1111/pce.13460] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 09/14/2018] [Accepted: 10/01/2018] [Indexed: 05/23/2023]
Abstract
Stomatal regulation is crucial for forest species performance and survival on drought-prone sites. We investigated the regulation of root and shoot hydraulics in three Pinus radiata clones exposed to drought stress and its coordination with stomatal conductance (gs ) and leaf water potential (Ψleaf ). All clones experienced a substantial decrease in root-specific root hydraulic conductance (Kroot-r ) in response to the water stress, but leaf-specific shoot hydraulic conductance (Kshoot-l ) did not change in any of the clones. The reduction in Kroot-r caused a decrease in leaf-specific whole-plant hydraulic conductance (Kplant-l ). Among clones, the larger the decrease in Kplant-l , the more stomata closed in response to drought. Rewatering resulted in a quick recovery of Kroot-r and gs . Our results demonstrated that the reduction in Kplant-l , attributed to a down regulation of aquaporin activity in roots, was linked to the isohydric stomatal behaviour, resulting in a nearly constant Ψleaf as water stress started. We concluded that higher Kplant-l is associated with water stress resistance by sustaining a less negative Ψleaf and delaying stomatal closure.
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Affiliation(s)
- Juan Rodríguez-Gamir
- Departamento de Suelos y Riegos, Instituto Canario de Investigaciones Agrarias (ICIA), Ctra de El boquerón s/n. 38270. San Cristóbal de La Laguna, Tenerife, Canary Islands, Spain
- Forest Systems, Scion, PO Box 29237, Christchurch, 8440, New Zealand
| | - Jianming Xue
- Forest Systems, Scion, PO Box 29237, Christchurch, 8440, New Zealand
| | - Michael J Clearwater
- Environmental Research Institute, University of Waikato, Private Bag 3105, Hamilton, New Zealand
| | - Dean F Meason
- Forest Systems, Scion, Private Bag 3020, Rotorua, 3046, New Zealand
| | - Peter W Clinton
- Forest Systems, Scion, PO Box 29237, Christchurch, 8440, New Zealand
| | - Jean-Christophe Domec
- Bordeaux Sciences Agro, UMR INRA ISPA 1391, Gradignan, France
- Nicholas School of the Environment, Duke University, Durham, North Carolina, USA
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Geng D, Chen P, Shen X, Zhang Y, Li X, Jiang L, Xie Y, Niu C, Zhang J, Huang X, Ma F, Guan Q. MdMYB88 and MdMYB124 Enhance Drought Tolerance by Modulating Root Vessels and Cell Walls in Apple. PLANT PHYSIOLOGY 2018; 178:1296-1309. [PMID: 30190418 PMCID: PMC6236628 DOI: 10.1104/pp.18.00502] [Citation(s) in RCA: 99] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 08/26/2018] [Indexed: 05/18/2023]
Abstract
Water deficit is one of the main limiting factors in apple (Malus × domestica Borkh.) cultivation. Root architecture plays an important role in the drought tolerance of plants; however, research efforts to improve drought tolerance of apple trees have focused on aboveground targets. Due to the difficulties associated with visualization and data analysis, there is currently a poor understanding of the genetic players and molecular mechanisms involved in the root architecture of apple trees under drought conditions. We previously observed that MdMYB88 and its paralog MdMYB124 regulate apple tree root morphology. In this study, we found that MdMYB88 and MdMYB124 play important roles in maintaining root hydraulic conductivity under long-term drought conditions and therefore contribute toward adaptive drought tolerance. Further investigation revealed that MdMYB88 and MdMYB124 regulate root xylem development by directly binding MdVND6 and MdMYB46 promoters and thus influence expression of their target genes under drought conditions. In addition, MdMYB88 and MdMYB124 were shown to regulate the deposition of cellulose and lignin root cell walls in response to drought. Taken together, our results provide novel insights into the importance of MdMYB88 and MdMYB124 in root architecture, root xylem development, and secondary cell wall deposition in response to drought in apple trees.
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Affiliation(s)
- Dali Geng
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Pengxiang Chen
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xiaoxia Shen
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yi Zhang
- College of Forestry, Northwest A&F University, Yangling, Shaanxi 712100, P.R. China
| | - Xuewei Li
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Lijuan Jiang
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yinpeng Xie
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Chundong Niu
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Jing Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xiaohua Huang
- College of Forestry, Northwest A&F University, Yangling, Shaanxi 712100, P.R. China
| | - Fengwang Ma
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Qingmei Guan
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
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Zadworny M, Comas LH, Eissenstat DM. Linking fine root morphology, hydraulic functioning and shade tolerance of trees. ANNALS OF BOTANY 2018; 122:239-250. [PMID: 29897405 PMCID: PMC6070046 DOI: 10.1093/aob/mcy054] [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: 11/30/2017] [Accepted: 03/28/2018] [Indexed: 05/17/2023]
Abstract
Background and Aims Understanding root traits and their trade-off with other plant processes is important for understanding plant functioning in natural ecosystems as well as agricultural systems. The aim of the present study was to determine the relationship between root morphology and the hydraulic characteristics of several orders of fine roots (<2 mm) for species differing in shade tolerance (low, moderate and high). Methods The morphological, anatomical and hydraulic traits across five distal root orders were measured in species with different levels of shade tolerance and life history strategies. The species studied were Acer negundo, Acer rubrum, Acer saccharum, Betula alleghaniensis, Betula lenta, Quercus alba, Quercus rubra, Pinus strobus and Pinus virginiana. Key Results Compared with shade-tolerant species, shade-intolerant species produced thinner absorptive roots with smaller xylem lumen diameters and underwent secondary development less frequently, suggesting that they had shorter life spans. Shade-tolerant species had greater root specific hydraulic conductance among these roots due to having larger diameter xylems, although these roots had a lower calculated critical tension for conduit collapse. In addition, shade-intolerant species exhibited greater variation in hydraulic conductance across different root growth rings in woody transport roots of the same root order as compared with shade-tolerant species. Conclusions Plant growth strategies were extended to include root hydraulic properties. It was found that shade intolerance in trees was associated with conservative root hydraulics but greater plasticity in number of xylem conduits and hydraulic conductance. Root traits of shade-intolerant species were consistent with the ability to proliferate roots quickly for rapid water uptake needed to support rapid shoot growth, while minimizing risk in uncertain environments.
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Affiliation(s)
- Marcin Zadworny
- Institute of Dendrology, Polish Academy of Sciences, Parkowa, Kórnik, Poland
| | - Louise H Comas
- USDA-ARS Water Management Research Unit, Fort Collins, CO, USA
| | - David M Eissenstat
- Intercollege Graduate Degree Program in Plant Biology, Penn State University, University Park, PA, USA
- Department of Ecosystem Science and Management, Penn State University, University Park, PA, USA
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Salahuddin, Rewald B, Razaq M, Lixue Y, Li J, Khan F, Jie Z. Root order-based traits of Manchurian walnut & larch and their plasticity under interspecific competition. Sci Rep 2018; 8:9815. [PMID: 29959435 PMCID: PMC6026125 DOI: 10.1038/s41598-018-27832-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 05/31/2018] [Indexed: 11/14/2022] Open
Abstract
Manchurian walnut and larch are key timber species of northeast China but information on (fine) root traits of both species is scarce. Plasticity of root traits in mixed plantations has been studied rarely although this could give important insights into mechanisms of root competition. This study examined root traits by branching order in 30-yr-old monocultures and their plasticity in mixed plantations. In monocultures, Manchurian walnut and larch differed in key fine root traits. Larch roots hold more absorptive root orders, larger diameter and lower specific root length/area. Walnut root orders featured greater cortex:stele ratios, N-concentrations and respiration rates. Under interspecific competition, the proportion of walnut root tips increased, the biomass/length of larch root orders 1-3 decreased. Larch possessed a greater morphological and anatomical plasticity of terminal root orders than walnut. Mycorrhizal colonization rates of walnut were reduced. Both species differed fundamentally in their fine root properties. Absorptive fine root orders reacted plastic under interspecific competition while traits of higher root orders remained unchanged. In mixture, larch roots possessed a greater plasticity in traits related to resource uptake (efficiency) than walnut roots whose reaction norm is suggested to be predominantly based on interference competition via juglone exudation.
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Affiliation(s)
- Salahuddin
- School of Forestry, Northeast Forestry University, Harbin, China
- Agricultural Research Institute, Mingora, Pakistan
| | - Boris Rewald
- Department of Forest and Soil Sciences, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Muhammad Razaq
- School of Forestry, Northeast Forestry University, Harbin, China
| | - Yang Lixue
- School of Forestry, Northeast Forestry University, Harbin, China.
| | - Ji Li
- School of Forestry, Northeast Forestry University, Harbin, China
| | - Farmanullah Khan
- Department of soil and environmental science, The university of Agriculture, Peshawar, Pakistan
| | - Zhang Jie
- School of Forestry, Northeast Forestry University, Harbin, China
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Prinsi B, Negri AS, Failla O, Scienza A, Espen L. Root proteomic and metabolic analyses reveal specific responses to drought stress in differently tolerant grapevine rootstocks. BMC PLANT BIOLOGY 2018; 18:126. [PMID: 29925320 PMCID: PMC6011575 DOI: 10.1186/s12870-018-1343-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 06/06/2018] [Indexed: 05/15/2023]
Abstract
BACKGROUND Roots play a central role in plant response to water stress (WS). They are involved in its perception and signalling to the leaf as well as in allowing the plant to adapt to maintaining an adequate water balance. Only a few studies have investigated the molecular/biochemical responses to WS in roots of perennial plants, such as grapevine. This study compares two grapevine rootstock genotypes (i.e. 101.14 and M4) with different tolerance to WS, evaluating the responses at proteomic and metabolite levels. RESULTS WS induced changes in the abundance of several proteins in both genotypes (17 and 22% of the detected proteins in 101.14 and M4, respectively). The proteomic analysis revealed changes in many metabolic pathways that fitted well with the metabolite data. M4 showed metabolic responses which were potentially able to counteract the WS effects, such as the drop in cell turgor, increased oxidative stress and loss of cell structure integrity/functionality. However, in 101.14 it was evident that the roots were suffering more severely from these effects. We found that many proteins classified as active in energy metabolism, hormone metabolism, protein, secondary metabolism and stress functional classes showed particular differences between the two rootstocks. CONCLUSION The proteomic/metabolite comparative analysis carried out provides new information on the possible biochemical and molecular strategies adopted by grapevine roots to counteract WS. Although further work is needed to define in detail the role(s) of the proteins and metabolites that characterize WS response, this study, involving the M4 rootstock genotype, highlights that osmotic responses, modulations of C metabolism, mitochondrial functionality and some specific responses to stress occurring in the roots play a primary role in Vitis spp. tolerance to this type of abiotic stress.
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Affiliation(s)
- Bhakti Prinsi
- Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia (DiSAA), Università degli Studi di Milano, Via Celoria, 2, 20133 Milano, Italy
| | - Alfredo Simone Negri
- Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia (DiSAA), Università degli Studi di Milano, Via Celoria, 2, 20133 Milano, Italy
| | - Osvaldo Failla
- Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia (DiSAA), Università degli Studi di Milano, Via Celoria, 2, 20133 Milano, Italy
| | - Attilio Scienza
- Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia (DiSAA), Università degli Studi di Milano, Via Celoria, 2, 20133 Milano, Italy
| | - Luca Espen
- Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia (DiSAA), Università degli Studi di Milano, Via Celoria, 2, 20133 Milano, Italy
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Janská A, Svoboda P, Spiwok V, Kučera L, Ovesná J. The dehydration stress of couch grass is associated with its lipid metabolism, the induction of transporters and the re-programming of development coordinated by ABA. BMC Genomics 2018; 19:317. [PMID: 29720087 PMCID: PMC5930771 DOI: 10.1186/s12864-018-4700-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 04/18/2018] [Indexed: 11/10/2022] Open
Abstract
Background The wild relatives of crop species represent a potentially valuable source of novel genetic variation, particularly in the context of improving the crop’s level of tolerance to abiotic stress. The mechanistic basis of these tolerances remains largely unexplored. Here, the focus was to characterize the transcriptomic response of the nodes (meristematic tissue) of couch grass (a relative of barley) to dehydration stress, and to compare it to that of the barley crown formed by both a drought tolerant and a drought sensitive barley cultivar. Results Many of the genes up-regulated in the nodes by the stress were homologs of genes known to be mediated by abscisic acid during the response to drought, or were linked to either development or lipid metabolism. Transporters also featured prominently, as did genes acting on root architecture. The resilience of the couch grass node arise from both their capacity to develop an altered, more effective root architecture, but also from their formation of a lipid barrier on their outer surface and their ability to modify both their lipid metabolism and transporter activity when challenged by dehydration stress. Conclusions Our analysis revealed the nature of dehydration stress response in couch grass. We suggested the tolerance is associated with lipid metabolism, the induction of transporters and the re-programming of development coordinated by ABA. We also proved the applicability of barley microarray for couch grass stress-response analysis. Electronic supplementary material The online version of this article (10.1186/s12864-018-4700-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Anna Janská
- Faculty of Science, Charles University, Prague, Czech Republic
| | - Pavel Svoboda
- Division of Crop Genetics and Breeding, Crop Research Institute, Prague, Czech Republic. .,Factulty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Czech Republic.
| | - Vojtěch Spiwok
- Factulty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Czech Republic
| | - Ladislav Kučera
- Division of Crop Genetics and Breeding, Crop Research Institute, Prague, Czech Republic
| | - Jaroslava Ovesná
- Division of Crop Genetics and Breeding, Crop Research Institute, Prague, Czech Republic
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Wong DCJ, Zhang L, Merlin I, Castellarin SD, Gambetta GA. Structure and transcriptional regulation of the major intrinsic protein gene family in grapevine. BMC Genomics 2018; 19:248. [PMID: 29642857 PMCID: PMC5896048 DOI: 10.1186/s12864-018-4638-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 03/29/2018] [Indexed: 12/05/2022] Open
Abstract
Background The major intrinsic protein (MIP) family is a family of proteins, including aquaporins, which facilitate water and small molecule transport across plasma membranes. In plants, MIPs function in a huge variety of processes including water transport, growth, stress response, and fruit development. In this study, we characterize the structure and transcriptional regulation of the MIP family in grapevine, describing the putative genome duplication events leading to the family structure and characterizing the family’s tissue and developmental specific expression patterns across numerous preexisting microarray and RNAseq datasets. Gene co-expression network (GCN) analyses were carried out across these datasets and the promoters of each family member were analyzed for cis-regulatory element structure in order to provide insight into their transcriptional regulation. Results A total of 29 Vitis vinifera MIP family members (excluding putative pseudogenes) were identified of which all but two were mapped onto Vitis vinifera chromosomes. In this study, segmental duplication events were identified for five plasma membrane intrinsic protein (PIP) and four tonoplast intrinsic protein (TIP) genes, contributing to the expansion of PIPs and TIPs in grapevine. Grapevine MIP family members have distinct tissue and developmental expression patterns and hierarchical clustering revealed two primary groups regardless of the datasets analyzed. Composite microarray and RNA-seq gene co-expression networks (GCNs) highlighted the relationships between MIP genes and functional categories involved in cell wall modification and transport, as well as with other MIPs revealing a strong co-regulation within the family itself. Some duplicated MIP family members have undergone sub-functionalization and exhibit distinct expression patterns and GCNs. Cis-regulatory element (CRE) analyses of the MIP promoters and their associated GCN members revealed enrichment for numerous CREs including AP2/ERFs and NACs. Conclusions Combining phylogenetic analyses, gene expression profiling, gene co-expression network analyses, and cis-regulatory element enrichment, this study provides a comprehensive overview of the structure and transcriptional regulation of the grapevine MIP family. The study highlights the duplication and sub-functionalization of the family, its strong coordinated expression with genes involved in growth and transport, and the putative classes of TFs responsible for its regulation. Electronic supplementary material The online version of this article (10.1186/s12864-018-4638-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Darren Chern Jan Wong
- Wine Research Centre, University of British Columbia, 2205 East Mall, Vancouver, BC, V6T 0Z4, Canada
| | - Li Zhang
- Bordeaux Science Agro, Institut des Sciences de la Vigne et du Vin, Ecophysiologie et Génomique Fonctionnelle de la Vigne, UMR 1287, F- 33140, Villenave d'Ornon, France
| | - Isabelle Merlin
- Bordeaux Science Agro, Institut des Sciences de la Vigne et du Vin, Ecophysiologie et Génomique Fonctionnelle de la Vigne, UMR 1287, F- 33140, Villenave d'Ornon, France
| | - Simone D Castellarin
- Wine Research Centre, University of British Columbia, 2205 East Mall, Vancouver, BC, V6T 0Z4, Canada
| | - Gregory A Gambetta
- Bordeaux Science Agro, Institut des Sciences de la Vigne et du Vin, Ecophysiologie et Génomique Fonctionnelle de la Vigne, UMR 1287, F- 33140, Villenave d'Ornon, France.
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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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43
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McMurtrie RE, Näsholm T. Quantifying the contribution of mass flow to nitrogen acquisition by an individual plant root. THE NEW PHYTOLOGIST 2018; 218:119-130. [PMID: 29226964 DOI: 10.1111/nph.14927] [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: 07/18/2017] [Accepted: 10/24/2017] [Indexed: 06/07/2023]
Abstract
The classic model of nitrogen (N) flux into roots is as a Michaelis-Menten (MM) function of soil-N concentration at root surfaces. Furthermore, soil-N transport processes that determine soil-N concentration at root surfaces are seen as a bottleneck for plant nutrition. Yet, neither the MM relationship nor soil-N transport mechanisms are represented in current terrestrial biosphere models. Processes governing N supply to roots - diffusion, mass flow, N immobilization by soil microbes - are incorporated in a model of root-N uptake. We highlight a seldom considered interaction between these processes: nutrient traverses the rhizosphere more quickly in the presence of mass flow, reducing the probability of its immobilization before reaching the root surface. Root-N uptake is sensitive to the rate of mass flow for widely spaced roots with high N uptake capacity, but not for closely spaced roots or roots with low uptake capacity. The results point to a benefit of root switching from high- to low-affinity N transport systems in the presence of mass flow. Simulations indicate a strong impact of soil water uptake on N delivery to widely spaced roots through transpirationally driven mass flow. Furthermore, a given rate of N uptake per unit soil volume may be achieved by lower root biomass in the presence of mass flow.
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Affiliation(s)
- Ross E McMurtrie
- School of Biological, Earth and Environmental Sciences, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - Torgny Näsholm
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, SE-901 83, Sweden
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Kim YX, Ranathunge K, Lee S, Lee Y, Lee D, Sung J. Composite Transport Model and Water and Solute Transport across Plant Roots: An Update. FRONTIERS IN PLANT SCIENCE 2018; 9:193. [PMID: 29503659 PMCID: PMC5820301 DOI: 10.3389/fpls.2018.00193] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 02/01/2018] [Indexed: 05/19/2023]
Abstract
The present review examines recent experimental findings in root transport phenomena in terms of the composite transport model (CTM). It has been a well-accepted conceptual model to explain the complex water and solute flows across the root that has been related to the composite anatomical structure. There are three parallel pathways involved in the transport of water and solutes in roots - apoplast, symplast, and transcellular paths. The role of aquaporins (AQPs), which facilitate water flows through the transcellular path, and root apoplast is examined in terms of the CTM. The contribution of the plasma membrane bound AQPs for the overall water transport in the whole plant level was varying depending on the plant species, age of roots with varying developmental stages of apoplastic barriers, and driving forces (hydrostatic vs. osmotic). Many studies have demonstrated that the apoplastic barriers, such as Casparian bands in the primary anticlinal walls and suberin lamellae in the secondary cell walls, in the endo- and exodermis are not perfect barriers and unable to completely block the transport of water and some solute transport into the stele. Recent research on water and solute transport of roots with and without exodermis triggered the importance of the extension of conventional CTM adding resistances that arrange in series (epidermis, exodermis, mid-cortex, endodermis, and pericycle). The extension of the model may answer current questions about the applicability of CTM for composite water and solute transport of roots that contain complex anatomical structures with heterogeneous cell layers.
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Affiliation(s)
- Yangmin X. Kim
- Division of Soil and Fertilizer, National Institute of Agricultural Sciences, Rural Development Administration, Wanju, South Korea
| | - Kosala Ranathunge
- School of Biological Sciences, The University of Western Australia, Perth, WA, Australia
| | - Seulbi Lee
- Division of Soil and Fertilizer, National Institute of Agricultural Sciences, Rural Development Administration, Wanju, South Korea
| | - Yejin Lee
- Division of Soil and Fertilizer, National Institute of Agricultural Sciences, Rural Development Administration, Wanju, South Korea
| | - Deogbae Lee
- Division of Soil and Fertilizer, National Institute of Agricultural Sciences, Rural Development Administration, Wanju, South Korea
| | - Jwakyung Sung
- Division of Soil and Fertilizer, National Institute of Agricultural Sciences, Rural Development Administration, Wanju, South Korea
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45
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Fricke W. Water transport and energy. PLANT, CELL & ENVIRONMENT 2017; 40:977-994. [PMID: 27756100 DOI: 10.1111/pce.12848] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 10/08/2016] [Accepted: 10/10/2016] [Indexed: 05/10/2023]
Abstract
Water transport in plants occurs along various paths and is driven by gradients in its free energy. It is generally considered that the mode of transport, being either diffusion or bulk flow, is a passive process, although energy may be required to sustain the forces driving water flow. This review aims at putting water flow at the various organisational levels (cell, organ, plant) in the context of the energy that is required to maintain these flows. In addition, the question is addressed (1) whether water can be transported against a difference in its chemical free energy, 'water potential' (Ψ), through, directly or indirectly, active processes; and (2) whether the energy released when water is flowing down a gradient in its energy, for example during day-time transpiration and cell expansive growth, is significant compared to the energy budget of plant and cell. The overall aim of review is not so much to provide a definite 'Yes' and 'No' to these questions, but rather to stimulate discussion and raise awareness that water transport in plants has its real, associated, energy costs and potential energy gains.
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Affiliation(s)
- Wieland Fricke
- School of Biology and Environmental Sciences, University College Dublin (UCD), Belfield, Dublin, 4, Ireland
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46
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Chenenaoui S, Daldoul S, Mliki A. High quality RNA from hydroponically grown grapevine roots suitable for gene expression studies. TURKISH JOURNAL OF BIOCHEMISTRY 2017. [DOI: 10.1515/tjb-2016-0301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractObjectives:Grapevine root system plays a great role in sensing and adapting to abiotic and biotic stresses. Identification of candidate genes involved in the tolerance to abiotic stress is becoming a crucial strategy to select and breed resilient genotypes. However, obtaining high quality RNA from grapevine roots under hydroponic culture is difficult. Hence, we have developed a new extraction procedure to improve RNA quality for root gene expression studies.Methods:Conventional RNA extraction methods using CTAB are not suitable for gene expression studies and need to be improved. Here we report the application of a CTAB- based method for RNA extraction using an additional clean-up purification step.Results:The RIN value of the resulting RNA indicated that our procedure allowed the purification of high RNA quality and quantity. Hence, the clean-up purification step efficiently eliminated contaminants which inhibit downstream applications. Derived RNA was successfully used for differential gene expression analysis in salt stressed grapevine by Northern Blot hybridizations.Conclusion:In this study, we developed an efficient RNA isolation protocol from hydroponic cultivated grapevine roots which yielded RNA suitable for gene expression studies. This will open large perspectives in grapevine functional genomics with the identification of pertinent genes of agronomic interest.
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48
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Tao Q, Jupa R, Luo J, Lux A, Kováč J, Wen Y, Zhou Y, Jan J, Liang Y, Li T. The apoplasmic pathway via the root apex and lateral roots contributes to Cd hyperaccumulation in the hyperaccumulator Sedum alfredii. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:739-751. [PMID: 28204505 PMCID: PMC5441904 DOI: 10.1093/jxb/erw453] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Although the significance of apoplasmic barriers in roots with regards to the uptake of toxic elements is generally known, the contribution of apoplasmic bypasses (ABs) to cadmium (Cd) hyperaccumulation is little understood. Here, we employed a combination of stable isotopic tracer techniques, an ABs tracer, hydraulic measurements, suberin lamellae staining, metabolic inhibitors, and antitranspirants to investigate and quantify the impact of the ABs on translocation of Cd to the xylem in roots of a hyperaccumulating (H) ecotype and a non-hyperaccumulating (NH) ecotype of Sedum alfredii. In the H ecotype, the Cd content in the xylem sap was proportional to hydrostatic pressure, which was attributed to pressure-driven flow via the ABs. The contribution of the ABs to Cd transportation to the xylem was dependent on the Cd concentration applied to the H ecotype (up to 37% at the highest concentration used). Cd-treated H ecotype roots showed significantly higher hydraulic conductance compared with the NH ecotype (76 vs 52 × 10–8 m s–1MPa–1), which is in accordance with less extensive suberization due to reduced expression of suberin-related genes. The main entry sites of apoplasmically transported Cd were localized in the root apexes and lateral roots of the H ecotype, where suberin lamellae were not well developed. These findings highlight the significance of the apoplasmic bypass in Cd hyperaccumulation in hyperaccumulating ecotypes of S. alfredii.
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Affiliation(s)
- Qi Tao
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
- Department of Plant Physiology, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynska dolina, Bratislava, Slovakia
| | - Radek Jupa
- Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlarska, Brno, Czech Republic
| | - Jipeng Luo
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | - Alexander Lux
- Department of Plant Physiology, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynska dolina, Bratislava, Slovakia
| | - Ján Kováč
- Department of Plant Physiology, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynska dolina, Bratislava, Slovakia
| | - Yue Wen
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | - Yimei Zhou
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | - Japenga Jan
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | - Yongchao Liang
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | - Tingqiang Li
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
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Cuneo IF, Knipfer T, Brodersen CR, McElrone AJ. Mechanical Failure of Fine Root Cortical Cells Initiates Plant Hydraulic Decline during Drought. PLANT PHYSIOLOGY 2016; 172:1669-1678. [PMID: 27621427 PMCID: PMC5100794 DOI: 10.1104/pp.16.00923] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 09/08/2016] [Indexed: 05/20/2023]
Abstract
Root systems perform the crucial task of absorbing water from the soil to meet the demands of a transpiring canopy. Roots are thought to operate like electrical fuses, which break when carrying an excessive load under conditions of drought stress. Yet the exact site and sequence of this dysfunction in roots remain elusive. Using in vivo x-ray computed microtomography, we found that drought-induced mechanical failure (i.e. lacunae formation) in fine root cortical cells is the initial and primary driver of reduced fine root hydraulic conductivity (Lpr) under mild to moderate drought stress. Cortical lacunae started forming under mild drought stress (-0.6 MPa Ψstem), coincided with a dramatic reduction in Lpr, and preceded root shrinkage or significant xylem embolism. Only under increased drought stress was embolism formation observed in the root xylem, and it appeared first in the fine roots (50% loss of hydraulic conductivity [P50] reached at -1.8 MPa) and then in older, coarse roots (P50 = -3.5 MPa). These results suggest that cortical cells in fine roots function like hydraulic fuses that decouple plants from drying soil, thus preserving the hydraulic integrity of the plant's vascular system under early stages of drought stress. Cortical lacunae formation led to permanent structural damage of the root cortex and nonrecoverable Lpr, pointing to a role in fine root mortality and turnover under drought stress.
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Affiliation(s)
- Italo F Cuneo
- Department of Viticulture and Enology, University of California, Davis, California 95616 (I.F.C., T.K., A.J.M)
- School of Agronomy, Pontificia Universidad Católica de Valparaíso, Quillota, Chile (I.F.C.)
- School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511 (C.R.B.); and
- USDA-ARS, Crops Pathology and Genetics Research Unit, Davis, California 95616 (A.J.M.)
| | - Thorsten Knipfer
- Department of Viticulture and Enology, University of California, Davis, California 95616 (I.F.C., T.K., A.J.M)
- School of Agronomy, Pontificia Universidad Católica de Valparaíso, Quillota, Chile (I.F.C.)
- School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511 (C.R.B.); and
- USDA-ARS, Crops Pathology and Genetics Research Unit, Davis, California 95616 (A.J.M.)
| | - Craig R Brodersen
- Department of Viticulture and Enology, University of California, Davis, California 95616 (I.F.C., T.K., A.J.M)
- School of Agronomy, Pontificia Universidad Católica de Valparaíso, Quillota, Chile (I.F.C.)
- School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511 (C.R.B.); and
- USDA-ARS, Crops Pathology and Genetics Research Unit, Davis, California 95616 (A.J.M.)
| | - Andrew J McElrone
- Department of Viticulture and Enology, University of California, Davis, California 95616 (I.F.C., T.K., A.J.M);
- School of Agronomy, Pontificia Universidad Católica de Valparaíso, Quillota, Chile (I.F.C.);
- School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511 (C.R.B.); and
- USDA-ARS, Crops Pathology and Genetics Research Unit, Davis, California 95616 (A.J.M.)
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Ruiz M, Quiñones A, Martínez-Alcántara B, Aleza P, Morillon R, Navarro L, Primo-Millo E, Martínez-Cuenca MR. Tetraploidy Enhances Boron-Excess Tolerance in Carrizo Citrange (Citrus sinensis L. Osb. × Poncirus trifoliata L. Raf.). FRONTIERS IN PLANT SCIENCE 2016; 7:701. [PMID: 27252717 PMCID: PMC4879134 DOI: 10.3389/fpls.2016.00701] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 05/06/2016] [Indexed: 05/20/2023]
Abstract
UNLABELLED Tetraploidy modifies root anatomy which may lead to differentiated capacity to uptake and transport mineral elements. This work provides insights into physiological and molecular characters involved in boron (B) toxicity responses in diploid (2x) and tetraploid (4x) plants of Carrizo citrange (Citrus sinensis L. Osb. × Poncirus trifoliata L. Raf.), a widely used citrus rootstock. With B excess, 2x plants accumulated more B in leaves than 4x plants, which accounted for their higher B uptake and root-to-shoot transport rates. Ploidy did not modify the expression of membrane transporters NIP5 and BOR1 in roots. The cellular allocation of B excess differed between ploidy levels in the soluble fraction, which was lower in 4x leaves, while cell wall-linked B was similar in 2x and 4x genotypes. This correlates with the increased damage and stunted growth recorded in the 2x plants. The 4x roots were found to have fewer root tips, shorter specific root length, longer diameter, thicker exodermis and earlier tissue maturation in root tips, where the Casparian strip was detected at a shorter distance from the root apex than in the 2x roots. The results presented herein suggest that the root anatomical characters of the 4x plants play a key role in their lower B uptake capacity and root-to-shoot transport. HIGHLIGHTS Tetraploidy enhances B excess tolerance in citrange CarrizoExpression of NIP5 and BOR1 transporters and cell wall-bounded B are similar between ploidiesB tolerance is attributed to root anatomical modifications induced by genome duplicationThe rootstock 4x citrange carrizo may prevent citrus trees from B excess.
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Affiliation(s)
- Marta Ruiz
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones AgrariasMoncada, Spain
| | - Ana Quiñones
- Centro de Citricultura y Producción Vegetal, Instituto Valenciano de Investigaciones AgrariasMoncada, Spain
| | - Belén Martínez-Alcántara
- Centro de Citricultura y Producción Vegetal, Instituto Valenciano de Investigaciones AgrariasMoncada, Spain
| | - Pablo Aleza
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones AgrariasMoncada, Spain
| | - Raphaël Morillon
- UMR AGAP, Centre de Coopération Internationale en Recherche Agronomique Pour le DéveloppementMontpellier, France
| | - Luis Navarro
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones AgrariasMoncada, Spain
| | - Eduardo Primo-Millo
- Centro de Citricultura y Producción Vegetal, Instituto Valenciano de Investigaciones AgrariasMoncada, Spain
| | - Mary-Rus Martínez-Cuenca
- Centro de Citricultura y Producción Vegetal, Instituto Valenciano de Investigaciones AgrariasMoncada, Spain
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