1
|
Cusack DF, Christoffersen B, Smith-Martin CM, Andersen KM, Cordeiro AL, Fleischer K, Wright SJ, Guerrero-Ramírez NR, Lugli LF, McCulloch LA, Sanchez-Julia M, Batterman SA, Dallstream C, Fortunel C, Toro L, Fuchslueger L, Wong MY, Yaffar D, Fisher JB, Arnaud M, Dietterich LH, Addo-Danso SD, Valverde-Barrantes OJ, Weemstra M, Ng JC, Norby RJ. Toward a coordinated understanding of hydro-biogeochemical root functions in tropical forests for application in vegetation models. New Phytol 2024; 242:351-371. [PMID: 38416367 DOI: 10.1111/nph.19561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 01/10/2024] [Indexed: 02/29/2024]
Abstract
Tropical forest root characteristics and resource acquisition strategies are underrepresented in vegetation and global models, hampering the prediction of forest-climate feedbacks for these carbon-rich ecosystems. Lowland tropical forests often have globally unique combinations of high taxonomic and functional biodiversity, rainfall seasonality, and strongly weathered infertile soils, giving rise to distinct patterns in root traits and functions compared with higher latitude ecosystems. We provide a roadmap for integrating recent advances in our understanding of tropical forest belowground function into vegetation models, focusing on water and nutrient acquisition. We offer comparisons of recent advances in empirical and model understanding of root characteristics that represent important functional processes in tropical forests. We focus on: (1) fine-root strategies for soil resource exploration, (2) coupling and trade-offs in fine-root water vs nutrient acquisition, and (3) aboveground-belowground linkages in plant resource acquisition and use. We suggest avenues for representing these extremely diverse plant communities in computationally manageable and ecologically meaningful groups in models for linked aboveground-belowground hydro-nutrient functions. Tropical forests are undergoing warming, shifting rainfall regimes, and exacerbation of soil nutrient scarcity caused by elevated atmospheric CO2. The accurate model representation of tropical forest functions is crucial for understanding the interactions of this biome with the climate.
Collapse
Affiliation(s)
- Daniela F Cusack
- Department of Ecosystem Science and Sustainability, Warner College of Natural Resources, Colorado State University, 1231 Libbie Coy Way, A104, Fort Collins, CO, 80523-1476, USA
- Smithsonian Tropical Research Institute, Apartado, Balboa, 0843-03092, Panama
| | - Bradley Christoffersen
- School of Integrative Biological and Chemical Sciences, The University of Texas Rio Grande Valley, Edinburg, TX, 78539, USA
| | - Chris M Smith-Martin
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, MN, 55108, USA
| | | | - Amanda L Cordeiro
- Department of Ecosystem Science and Sustainability, Warner College of Natural Resources, Colorado State University, 1231 Libbie Coy Way, A104, Fort Collins, CO, 80523-1476, USA
- Smithsonian Tropical Research Institute, Apartado, Balboa, 0843-03092, Panama
| | - Katrin Fleischer
- Department Biogeochemical Signals, Max-Planck-Institute for Biogeochemistry, Hans-Knöll-Straße 10, Jena, 07745, Germany
| | - S Joseph Wright
- Smithsonian Tropical Research Institute, Apartado, Balboa, 0843-03092, Panama
| | - Nathaly R Guerrero-Ramírez
- Silviculture and Forest Ecology of Temperate Zones, Faculty of Forest Sciences and Forest Ecology, University of Göttingen, Gottingen, 37077, Germany
- Centre of Biodiversity and Sustainable Land Use (CBL), University of Göttingen, Gottingen, 37077, Germany
| | - Laynara F Lugli
- School of Life Sciences, Technical University of Munich, Freising, 85354, Germany
| | - Lindsay A McCulloch
- Department of Organismic and Evolutionary Biology, Harvard University, 26 Oxford St., Cambridge, MA, 02138, USA
- National Center for Atmospheric Research, National Oceanographic and Atmospheric Agency, 1850 Table Mesa Dr., Boulder, CO, 80305, USA
| | - Mareli Sanchez-Julia
- Department of Ecology and Evolutionary Biology, Tulane University, New Orleans, LA, 70118, USA
| | - Sarah A Batterman
- Smithsonian Tropical Research Institute, Apartado, Balboa, 0843-03092, Panama
- Cary Institute of Ecosystem Studies, Millbrook, NY, 12545, USA
- School of Geography, University of Leeds, Leeds, LS2 9JT, UK
| | - Caroline Dallstream
- Department of Biology, McGill University, 1205 Av. du Docteur-Penfield, Montreal, QC, H3A 1B1, Canada
| | - Claire Fortunel
- AMAP (Botanique et Modélisation de l'Architecture des Plantes et des Végétations), Université de Montpellier, CIRAD, CNRS, INRAE, IRD, Montpellier, 34398, France
| | - Laura Toro
- Yale Applied Science Synthesis Program, The Forest School at the Yale School of the Environment, Yale University, New Haven, CT, 06511, USA
| | - Lucia Fuchslueger
- Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, 1030, Austria
| | - Michelle Y Wong
- Cary Institute of Ecosystem Studies, Millbrook, NY, 12545, USA
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, 06511, USA
| | - Daniela Yaffar
- Functional Forest Ecology, Universität Hamburg, Barsbüttel, 22885, Germany
| | - Joshua B Fisher
- Schmid College of Science and Technology, Chapman University, 1 University Drive, Orange, CA, 92866, USA
| | - Marie Arnaud
- Institute of Ecology and Environmental Sciences (IEES), UMR 7618, CNRS-Sorbonne University-INRAE-UPEC-IRD, Paris, 75005, France
- School of Geography, Earth and Environmental Sciences & BIFOR, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Lee H Dietterich
- Department of Ecosystem Science and Sustainability, Warner College of Natural Resources, Colorado State University, 1231 Libbie Coy Way, A104, Fort Collins, CO, 80523-1476, USA
- U.S. Army Engineer Research and Development Center, Environmental Laboratory, Vicksburg, MS, 39180, USA
- Department of Biology, Haverford College, Haverford, PA, 19003, USA
| | - Shalom D Addo-Danso
- Forests and Climate Change Division, CSIR-Forestry Research Institute of Ghana, P.O Box UP 63 KNUST, Kumasi, Ghana
| | - Oscar J Valverde-Barrantes
- Department of Biological Sciences, International Center for Tropical Biodiversity, Florida International University, Miami, FL, 33199, USA
| | - Monique Weemstra
- Department of Biological Sciences, International Center for Tropical Biodiversity, Florida International University, Miami, FL, 33199, USA
| | - Jing Cheng Ng
- Nanyang Technological University, Singapore, 639798, Singapore
| | - Richard J Norby
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN, 37996, USA
| |
Collapse
|
2
|
Roddy AB, Guilliams CM, Fine PVA, Mambelli S, Dawson TE, Simonin KA. Flowers are leakier than leaves but cheaper to build. New Phytol 2023; 239:2076-2082. [PMID: 37366068 DOI: 10.1111/nph.19104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 05/29/2023] [Indexed: 06/28/2023]
Affiliation(s)
- Adam B Roddy
- Institute of Environment, Department of Biological Sciences, Florida International University, Miami, 33199, FL, USA
| | | | - Paul V A Fine
- Department of Integrative Biology, University of California-Berkeley, Berkeley, 94720, CA, USA
| | - Stefania Mambelli
- Department of Integrative Biology, University of California-Berkeley, Berkeley, 94720, CA, USA
| | - Todd E Dawson
- Department of Integrative Biology, University of California-Berkeley, Berkeley, 94720, CA, USA
| | - Kevin A Simonin
- Department of Biology, San Francisco State University, San Francisco, 94132, CA, USA
| |
Collapse
|
3
|
An YD, Roddy AB, Zhang TH, Jiang GF. Hydraulic differences between flowers and leaves are driven primarily by pressure-volume traits and water loss. Front Plant Sci 2023; 14:1130724. [PMID: 37324689 PMCID: PMC10264769 DOI: 10.3389/fpls.2023.1130724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 05/16/2023] [Indexed: 06/17/2023]
Abstract
Flowers are critical for successful reproduction and have been a major axis of diversification among angiosperms. As the frequency and severity of droughts are increasing globally, maintaining water balance of flowers is crucial for food security and other ecosystem services that rely on flowering. Yet remarkably little is known about the hydraulic strategies of flowers. We characterized hydraulic strategies of leaves and flowers of ten species by combining anatomical observations using light and scanning electron microscopy with measurements of hydraulic physiology (minimum diffusive conductance (g min) and pressure-volume (PV) curves parameters). We predicted that flowers would exhibit higher g min and higher hydraulic capacitance than leaves, which would be associated with differences in intervessel pit traits because of their different hydraulic strategies. We found that, compared to leaves, flowers exhibited: 1) higher g min, which was associated with higher hydraulic capacitance (C T); 2) lower variation in intervessel pit traits and differences in pit membrane area and pit aperture shape; and 3) independent coordination between intervessel pit traits and other anatomical and physiological traits; 4) independent evolution of most traits in flowers and leaves, resulting in 5) large differences in the regions of multivariate trait space occupied by flowers and leaves. Furthermore, across organs intervessel pit trait variation was orthogonal to variation in other anatomical and physiological traits, suggesting that pit traits represent an independent axis of variation that have as yet been unquantified in flowers. These results suggest that flowers, employ a drought-avoidant strategy of maintaining high capacitance that compensates for their higher g min to prevent excessive declines in water potentials. This drought-avoidant strategy may have relaxed selection on intervessel pit traits and allowed them to vary independently from other anatomical and physiological traits. Furthermore, the independent evolution of floral and foliar anatomical and physiological traits highlights their modular development despite being borne from the same apical meristem.
Collapse
Affiliation(s)
- Yi-Dong An
- Guangxi Key Laboratory of Forest Ecology and Conservation, Guangxi Colleges and Universities Key Laboratory for Cultivation and Utilization of Subtropical Forest Plantation, and State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Forestry, Guangxi University, Nanning, Guangxi, China
| | - Adam B. Roddy
- Institute of Environment, Department of Biological Sciences, Florida International University, Miami, FL, United States
| | - Tian-Hao Zhang
- Guangxi Key Laboratory of Forest Ecology and Conservation, Guangxi Colleges and Universities Key Laboratory for Cultivation and Utilization of Subtropical Forest Plantation, and State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Forestry, Guangxi University, Nanning, Guangxi, China
| | - Guo-Feng Jiang
- Guangxi Key Laboratory of Forest Ecology and Conservation, Guangxi Colleges and Universities Key Laboratory for Cultivation and Utilization of Subtropical Forest Plantation, and State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Forestry, Guangxi University, Nanning, Guangxi, China
| |
Collapse
|
4
|
Fortunel C, Stahl C, Coste S, Ziegler C, Derroire G, Levionnois S, Maréchaux I, Bonal D, Hérault B, Wagner FH, Sack L, Chave J, Heuret P, Jansen S, John G, Scoffoni C, Trueba S, Bartlett MK. Thresholds for persistent leaf photochemical damage predict plant drought resilience in a tropical rainforest. New Phytol 2023. [PMID: 37222272 DOI: 10.1111/nph.18973] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 04/12/2023] [Indexed: 05/25/2023]
Abstract
Water stress can cause declines in plant function that persist after rehydration. Recent work has defined 'resilience' traits characterizing leaf resistance to persistent damage from drought, but whether these traits predict resilience in whole-plant function is unknown. It is also unknown whether the coordination between resilience and 'resistance' - the ability to maintain function during drought - observed globally occurs within ecosystems. For eight rainforest species, we dehydrated and subsequently rehydrated leaves, and measured water stress thresholds for declines in rehydration capacity and maximum quantum yield of photosystem II (Fv /Fm ). We tested correlations with embolism resistance and dry season water potentials (ΨMD ), and calculated safety margins for damage (ΨMD - thresholds) and tested correlations with drought resilience in sap flow and growth. Ψ thresholds for persistent declines in Fv /Fm , indicating resilience, were positively correlated with ΨMD and thresholds for leaf vein embolism. Safety margins for persistent declines in Fv /Fm , but not rehydration capacity, were positively correlated with drought resilience in sap flow. Correlations between resistance and resilience suggest that species' differences in performance during drought are perpetuated after drought, potentially accelerating shifts in forest composition. Resilience to photochemical damage emerged as a promising functional trait to characterize whole-plant drought resilience.
Collapse
Affiliation(s)
- Claire Fortunel
- AMAP (Botanique et Modélisation de l'Architecture des Plantes et des Végétations), Université de Montpellier, CIRAD, CNRS, INRAE, IRD, 34000, Montpellier, France
| | - Clément Stahl
- INRAE, UMR EcoFoG, CNRS, CIRAD, AgroParisTech, Université des Antilles, Université de Guyane, 97310, Kourou, France
| | - Sabrina Coste
- INRAE, UMR EcoFoG, CNRS, CIRAD, AgroParisTech, Université des Antilles, Université de Guyane, 97310, Kourou, France
| | - Camille Ziegler
- INRAE, UMR EcoFoG, CNRS, CIRAD, AgroParisTech, Université des Antilles, Université de Guyane, 97310, Kourou, France
- Université de Lorraine, AgroParisTech, INRAE, UMR Silva, 54000, Nancy, France
| | - Géraldine Derroire
- CIRAD, UMR EcoFoG (AgroParistech, CNRS, INRAE, Université des Antilles, Université de la Guyane), Campus Agronomique, 97310, Kourou, French Guiana
| | - Sébastien Levionnois
- AMAP (Botanique et Modélisation de l'Architecture des Plantes et des Végétations), Université de Montpellier, CIRAD, CNRS, INRAE, IRD, 34000, Montpellier, France
- INRAE, UMR EcoFoG, CNRS, CIRAD, AgroParisTech, Université des Antilles, Université de Guyane, 97310, Kourou, France
| | - Isabelle Maréchaux
- AMAP (Botanique et Modélisation de l'Architecture des Plantes et des Végétations), Université de Montpellier, CIRAD, CNRS, INRAE, IRD, 34000, Montpellier, France
| | - Damien Bonal
- Université de Lorraine, AgroParisTech, INRAE, UMR Silva, 54000, Nancy, France
| | - Bruno Hérault
- CIRAD, UPR Forêts et Sociétés, Yamoussoukro, Côte d'Ivoire
- Forêts et Sociétés, Univ Montpellier, CIRAD, 34000, Montpellier, France
- Institut National Polytechnique Félix Houphouët-Boigny, INP-HB, Yamoussoukro, Côte d'Ivoire
| | - Fabien H Wagner
- Institute of Environment and Sustainability, University of California, Los Angeles, CA, 90095, USA
- Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove, Pasadena, CA, 91109, USA
| | - Lawren Sack
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA, 90095, USA
| | - Jérôme Chave
- CNRS, Université Toulouse 3 Paul Sabatier, IRD, UMR 5174 Evolution et Diversité Biologique (EDB), 31062, Toulouse, France
| | - Patrick Heuret
- AMAP (Botanique et Modélisation de l'Architecture des Plantes et des Végétations), Université de Montpellier, CIRAD, CNRS, INRAE, IRD, 34000, Montpellier, France
| | - Steven Jansen
- Institute of Botany, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Grace John
- Department of Biology, University of Florida, Gainesville, FL, 32611, USA
| | - Christine Scoffoni
- Department of Biological Sciences, California State University, Los Angeles, CA, 90032, USA
| | - Santiago Trueba
- Université de Bordeaux, INRAE, UMR BIOGECO, Pessac, 33615, France
| | - Megan K Bartlett
- Department of Viticulture and Enology, University of California, Davis, CA, 95616, USA
| |
Collapse
|
5
|
Fuenzalida TI, Blacker MJ, Turner M, Sheppard A, Ball MC. Foliar water uptake enables embolism removal in excised twigs of Avicennia marina. New Phytol 2023; 237:1136-1145. [PMID: 36372990 DOI: 10.1111/nph.18613] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 10/28/2022] [Indexed: 06/16/2023]
Abstract
Embolism refilling is thought to require relaxation of xylem tension, and it is unclear whether and how tall trees or plants growing in arid or saline soils recover from embolism. We tested whether foliar water uptake could enable embolism refilling in dehydrated twigs of the grey mangrove (Avicennia marina). Four dehydrated twigs were imaged by laboratory-based micro-computed tomography before and after wetting leaves. Emboli were observed in dehydrated stems and leaves. Embolism decreased with increasing distance from the cut end of stems, suggesting that stem emboli were caused by cutting. A significant (P = 0.026) c. 80% reduction in the embolised area was observed in leaves between the start and the end of the experiment (29 ± 10 h after wetting). Embolus diameter was unaffected by wetting. Embolism refilling occurred slowly, in stems embolised by cutting and leaves embolised by cutting and/or dehydration. The lack of response of embolus diameter to wetting suggests that capillarity was not the main mechanism for refilling. Results show that excised twigs of A. marina are able to recover from embolism by absorption of atmospheric water and call for studies under natural conditions.
Collapse
Affiliation(s)
- Tomás I Fuenzalida
- Plant Science Division, Research School of Biology, The Australian National University, Acton, ACT, 2601, Australia
| | - Matthew J Blacker
- Department of Quantum Science, Research School of Physics, Australian National University, Canberra, ACT, 2601, Australia
| | - Michael Turner
- Department of Applied Mathematics, Research School of Physics, Australian National University, Canberra, ACT, 2601, Australia
| | - Adrian Sheppard
- Department of Applied Mathematics, Research School of Physics, Australian National University, Canberra, ACT, 2601, Australia
| | - Marilyn C Ball
- Plant Science Division, Research School of Biology, The Australian National University, Acton, ACT, 2601, Australia
| |
Collapse
|
6
|
Suissa JS, Agbleke AA, Friedman WE. A bump in the node: The hydraulic implications of rhizomatous growth. Am J Bot 2023; 110:e16105. [PMID: 36401563 DOI: 10.1002/ajb2.16105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 11/06/2022] [Accepted: 11/08/2022] [Indexed: 06/16/2023]
Abstract
PREMISE Rhizomatous growth characterizes numerous taxa among vascular plants. While abundant information exists on nutrient sharing and demography, the question of how these metameric organisms move water through their bodies remains largely unstudied. Moreover, we lack an understanding of the evolutionary implications of rhizomatous growth across vascular plants. Here, we examined these questions by investigating how rhizomatous growth and vascular construction affect whole-plant hydraulic function. METHODS In five terrestrial fern species with diverse vascular construction, we used microcomputed tomography and bright-field microscopy to examine vascular construction across nodes along the rhizome. These data were integrated with measurements of leaf stomatal conductance under rooted and uprooted conditions to relate vascular patterning and hydraulic architecture to leaf water status. RESULTS Similar to phytomers of woody seed plants, nodal regions in rhizomatous ferns are areas of hydraulic resistance. While water is shared along the rhizomes of these investigated species, hydraulic conductivity drops at nodes and stomatal conductance declines when nodes were locally uprooted. Together, our data suggest that nodes are chokepoints in axial water movement along the rhizome. CONCLUSIONS Nodal chokepoints decrease hydraulic integration between phytomers. At the same time, chokepoints may act as "safety valves", hydraulically localizing each phytomer-potentially decreasing embolism and pathogen spread. This suggests a potential trade-off in the principal construction of the fern rhizome. Moreover, we propose that shoot-borne roots (homorhizy) and the prostrate habit of rhizomatous ferns decrease the hydraulic and structural burdens that upright plants typically incur. The absence of these hydraulic and structural demands may be one reason ferns (and many rhizomatous plants) lack, or have minimally developed, secondary xylem.
Collapse
Affiliation(s)
- Jacob S Suissa
- The Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
- The Arnold Arboretum of Harvard University, Boston, MA, USA
| | | | - William E Friedman
- The Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
- The Arnold Arboretum of Harvard University, Boston, MA, USA
| |
Collapse
|
7
|
Li C, Gao T, Wang X, Qu S, Yang Y, Zuo M, Wang J, Wang H, Zhou G, Liu Y. Phytoremediation Potential and Physiological Mechanisms Underlying Metallic Extraction of Suaeda glauca, Artemisia desertorum, and Atriplex canescens. Int J Environ Res Public Health 2022; 19:16035. [PMID: 36498118 PMCID: PMC9736508 DOI: 10.3390/ijerph192316035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 11/23/2022] [Accepted: 11/24/2022] [Indexed: 06/17/2023]
Abstract
Mining activities have led to serious environmental (soil erosion, degradation of vegetation, and groundwater contamination) and human health (musculoskeletal problems, diarrheal conditions, and chronic diseases) issues at desert mining areas in northwest China. Native plant species grown naturally in desert regions show a unique tolerance to arid and semiarid conditions and are potential candidates for soil phytoremediation. Here, an ex situ experiment involving pot planting of seedlings of three native plant species (Suaeda glauca, Artemisia desertorum, and Atriplex canescens) was designed to explore their phytoremediation potential and the underlying physiological mechanism. For Zn and Cu, the three plants were all with a biological accumulation coefficient (BAC) greater than 1. For Cd, Ni, and Pb, Atriplex canescens had the highest bioaccumulation concentrations (521.52, 862.23, and 1734.59 mg/kg), with BAC values (1.06, 1.30, 1.25) greater than 1, which indicates that Atriplex canescens could be a broad-spectrum metal extraction plant. Physiological analysis (antioxidation, extracellular secretions, photosynthesis, and hydraulics) showed that the three desert plants exploited their unique strategy to protect against the stress of complex metals in soils. Moreover, the second growing period was the main heavy metal accumulation and extraction stage concomitant with highest water use efficiency (iWUE). Taken together, the three desert plants exhibited the potent heavy metal extraction ability and physiological and ecological adaptability to a harsh polluted environment in arid desert areas, providing potential resources for the bioremediation of metal-contaminated soils in an arid and semiarid desert environment.
Collapse
Affiliation(s)
- Changming Li
- College of Chemistry and Chemical Engineering, Qinghai Normal University, Xining 810008, China
- Research Center of Pollution Control and Ecological Restoration Engineering in Mining Area of Gansu Province, Lanzhou 730001, China
| | - Tianpeng Gao
- Research Center of Pollution Control and Ecological Restoration Engineering in Mining Area of Gansu Province, Lanzhou 730001, China
- College of Biological and Environmental Engineering, Xi’an University, Xi’an 710065, China
| | - Xueying Wang
- Xi’an Institute of Environment Sanitation Sciences, Xi’an 710065, China
| | - Shipeng Qu
- Research Center of Pollution Control and Ecological Restoration Engineering in Mining Area of Gansu Province, Lanzhou 730001, China
- Gansu Jinchang Environmental Monitoring Center, Jinchang 737100, China
| | - Yingli Yang
- Research Center of Pollution Control and Ecological Restoration Engineering in Mining Area of Gansu Province, Lanzhou 730001, China
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou 730070, China
| | - Mingbo Zuo
- Research Center of Pollution Control and Ecological Restoration Engineering in Mining Area of Gansu Province, Lanzhou 730001, China
- College of Life Science, Northwest Normal University, Lanzhou 730070, China
| | - Juan Wang
- Research Center of Pollution Control and Ecological Restoration Engineering in Mining Area of Gansu Province, Lanzhou 730001, China
- College of Life Science, Northwest Normal University, Lanzhou 730070, China
| | - Haoming Wang
- Research Center of Pollution Control and Ecological Restoration Engineering in Mining Area of Gansu Province, Lanzhou 730001, China
- College of Biological and Pharmaceutical Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China
| | - Guixiang Zhou
- Research Center of Pollution Control and Ecological Restoration Engineering in Mining Area of Gansu Province, Lanzhou 730001, China
- Nanjing Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210018, China
| | - Yubing Liu
- Research Center of Pollution Control and Ecological Restoration Engineering in Mining Area of Gansu Province, Lanzhou 730001, China
- State Key Laboratory of Grassland Agro-Ecosystems, Lanzhou University, Lanzhou 730020, China
| |
Collapse
|
8
|
Gao T, Wang H, Li C, Zuo M, Wang X, Liu Y, Yang Y, Xu D, Liu Y, Fang X. Effects of Heavy Metal Stress on Physiology, Hydraulics, and Anatomy of Three Desert Plants in the Jinchang Mining Area, China. Int J Environ Res Public Health 2022; 19:15873. [PMID: 36497949 PMCID: PMC9738440 DOI: 10.3390/ijerph192315873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/09/2022] [Accepted: 11/25/2022] [Indexed: 06/17/2023]
Abstract
The physiological mechanisms and phytoremediation effects of three kinds of native quinoa in a desert mining area were studied. We used two different types of local soils (native soil and tailing soil) to analyze the changes in the heavy metal content, leaf physiology, photosynthetic parameters, stem hydraulics, and anatomical characteristics of potted quinoa. The results show that the chlorophyll content, photosynthetic rate, stomatal conductance, and transpiration rate of Kochia scoparia were decreased, but intercellular CO2 concentration (Ci) was increased under heavy metal stress, and the net photosynthetic rate (Pn) was decreased due to non-stomatal limitation. The gas exchange of Chenopodium glaucum and Atriplex centralasiatica showed a decrease in Pn, stomatal conductance (Gs), and transpiration rate (E) due to stomatal limitation. The three species showed a similar change in heavy metal content; they all showed elevated hydraulic parameters, decreased vessel density, and significantly thickened vessel walls under heavy metal stress. Physiological indicators such as proline content and activity of superoxide dismutase (SOD) and peroxidase (POD) increased, but the content of malondialdehyde (MDA) and glutathione (GSH), as well as catalase (CAT) activity, decreased in these three plants. Therefore, it can be concluded that these three species of quinoa, possibly the most dominant 30 desert plants in the region, showed a good adaptability and accumulation capacity under the pressure of heavy metal stress, and these plants can be good candidates for tailings remediation in the Jinchang desert mining area.
Collapse
Affiliation(s)
- Tianpeng Gao
- School of Biological and Environmental Engineering, Xi’an University, Xi’an 710065, China
- School of Biological and Pharmaceutical Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China
- Engineering Center for Pollution Control and Ecological Restoration in Mining of Gansu Province, Lanzhou City University, Lanzhou 730070, China
| | - Haoming Wang
- School of Biological and Pharmaceutical Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China
| | - Changming Li
- School of Biological and Environmental Engineering, Xi’an University, Xi’an 710065, China
| | - Mingbo Zuo
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
| | - Xueying Wang
- Institute of Environmental Health Science in Xi’an, Xi’an 710065, China
| | - Yuan Liu
- School of Biological and Pharmaceutical Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China
| | - Yingli Yang
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
| | - Danghui Xu
- State Key Laboratory of Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China
| | - Yubing Liu
- State Key Laboratory of Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China
| | - Xiangwen Fang
- State Key Laboratory of Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China
| |
Collapse
|
9
|
Brown A, Butler DW, Radford‐Smith J, Dwyer JM. Changes in trait covariance along an orographic moisture gradient reveal the relative importance of light- and moisture-driven trade-offs in subtropical rainforest communities. New Phytol 2022; 236:839-851. [PMID: 35922934 PMCID: PMC9804723 DOI: 10.1111/nph.18418] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 07/25/2022] [Indexed: 06/15/2023]
Abstract
A range of functional trait-based approaches have been developed to investigate community assembly processes, but most ignore how traits covary within communities. We combined existing approaches - community-weighted means (CWMs) and functional dispersion (FDis) - with a metric of trait covariance to examine assembly processes in five angiosperm assemblages along a moisture gradient in Australia's subtropics. In addition to testing hypotheses about habitat filtering along the gradient, we hypothesized that trait covariance would be strongest at both ends of the moisture gradient and weakest in the middle, reflecting trade-offs associated with light capture in productive sites and moisture stress in dry sites. CWMs revealed evidence of climatic filtering, but FDis patterns were less clear. As hypothesized, trait covariance was weakest in the middle of the gradient but unexpectedly peaked at the second driest site due to the emergence of a clear drought tolerance-drought avoidance spectrum. At the driest site, the same spectrum was truncated at the 'avoider' end, revealing important information about habitat filtering in this system. Our focus on trait covariance revealed the nature and strength of trade-offs imposed by light and moisture availability, complementing insights gained about community assembly from existing trait-based approaches.
Collapse
Affiliation(s)
- Alison Brown
- School of Biological SciencesThe University of QueenslandSt LuciaQld4072Australia
| | - Donald W. Butler
- College of LawAustralian National UniversityCanberraACT2600Australia
| | - Julian Radford‐Smith
- School of Biological SciencesThe University of QueenslandSt LuciaQld4072Australia
| | - John M. Dwyer
- School of Biological SciencesThe University of QueenslandSt LuciaQld4072Australia
| |
Collapse
|
10
|
Stokkermans A, Chakrabarti A, Subramanian K, Wang L, Yin S, Moghe P, Steenbergen P, Mönke G, Hiiragi T, Prevedel R, Mahadevan L, Ikmi A. Muscular hydraulics drive larva-polyp morphogenesis. Curr Biol 2022:S0960-9822(22)01387-2. [PMID: 36115340 DOI: 10.1016/j.cub.2022.08.065] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 07/14/2022] [Accepted: 08/22/2022] [Indexed: 11/22/2022]
Abstract
Development is a highly dynamic process in which organisms often experience changes in both form and behavior, which are typically coupled to each other. However, little is known about how organismal-scale behaviors such as body contractility and motility impact morphogenesis. Here, we use the cnidarian Nematostella vectensis as a developmental model to uncover a mechanistic link between organismal size, shape, and behavior. Using quantitative live imaging in a large population of developing animals, combined with molecular and biophysical experiments, we demonstrate that the muscular-hydraulic machinery that controls body movement also drives larva-polyp morphogenesis. We show that organismal size largely depends on cavity inflation through fluid uptake, whereas body shape is constrained by the organization of the muscular system. The generation of ethograms identifies different trajectories of size and shape development in sessile and motile animals, which display distinct patterns of body contractions. With a simple theoretical model, we conceptualize how pressures generated by muscular hydraulics can act as a global mechanical regulator that coordinates tissue remodeling. Altogether, our findings illustrate how organismal contractility and motility behaviors can influence morphogenesis.
Collapse
|
11
|
Manzi OJL, Bellifa M, Ziegler C, Mihle L, Levionnois S, Burban B, Leroy C, Coste S, Stahl C. Drought stress recovery of hydraulic and photochemical processes in Neotropical tree saplings. Tree Physiol 2022; 42:114-129. [PMID: 34302178 DOI: 10.1093/treephys/tpab092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 07/16/2021] [Indexed: 06/13/2023]
Abstract
Climate models predict an increase in the severity and the frequency of droughts. Tropical forests are among the ecosystems that could be highly impacted by these droughts. Here, we explore how hydraulic and photochemical processes respond to drought stress and re-watering. We conducted a pot experiment on saplings of five tree species. Before the onset of drought, we measured a set of hydraulic traits, including minimum leaf conductance, leaf embolism resistance and turgor loss point. During drought stress, we monitored traits linked to leaf hydraulic functioning (leaf water potential (ψmd) and stomatal conductance (gs)) and traits linked to leaf photochemical functioning (maximum quantum yield of photosystem II (Fv/Fm) and maximum electron transport rate (ETRmax)) at different wilting stages. After re-watering, the same traits were measured after 3, 7 and 14 days. Hydraulic trait values decreased faster than photochemical trait values. After re-watering, the values of the four traits recovered at different rates. Fv/Fm recovered very fast close to their initial values only 3 days after re-watering. This was followed by ETRmax, Ψmd and gs. Finally, we show that species with large stomatal and leaf safety margin and low πtlp are not strongly impacted by drought, whereas they have a low recovery on photochemical efficiency. These results demonstrate that πtlp, stomatal and leaf safety margin are a good indicators of plant responses to drought stress and also to recovery for photochemical efficiency.
Collapse
Affiliation(s)
- Olivier Jean Leonce Manzi
- UMR EcoFoG, CNRS, CIRAD, INRAE, AgroParisTech, Université des Antilles, Université de Guyane, 97310 Kourou, France
- Integrated Polytechnic Regional College-Kitabi, Rwanda Polytechnic, PO Box 330, Huye, Rwanda
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, SE-40530 Gothenburg, Sweden
| | - Maxime Bellifa
- UMR EcoFoG, CNRS, CIRAD, INRAE, AgroParisTech, Université des Antilles, Université de Guyane, 97310 Kourou, France
| | - Camille Ziegler
- UMR EcoFoG, CNRS, CIRAD, INRAE, AgroParisTech, Université des Antilles, Université de Guyane, 97310 Kourou, France
- Université de Lorraine, AgroParisTech, INRAE, UMR Silva, 54000 Nancy, France
| | - Louis Mihle
- UMR EcoFoG, CNRS, CIRAD, INRAE, AgroParisTech, Université des Antilles, Université de Guyane, 97310 Kourou, France
| | - Sébastien Levionnois
- UMR EcoFoG, CNRS, CIRAD, INRAE, AgroParisTech, Université des Antilles, Université de Guyane, 97310 Kourou, France
- AMAP, Univ Montpellier, CIRAD, CNRS, INRAE, IRD, 34000 Montpellier, France
| | - Benoit Burban
- UMR EcoFoG, CNRS, CIRAD, INRAE, AgroParisTech, Université des Antilles, Université de Guyane, 97310 Kourou, France
| | - Céline Leroy
- UMR EcoFoG, CNRS, CIRAD, INRAE, AgroParisTech, Université des Antilles, Université de Guyane, 97310 Kourou, France
- AMAP, Univ Montpellier, CIRAD, CNRS, INRAE, IRD, 34000 Montpellier, France
| | - Sabrina Coste
- UMR EcoFoG, CNRS, CIRAD, INRAE, AgroParisTech, Université des Antilles, Université de Guyane, 97310 Kourou, France
| | - Clément Stahl
- UMR EcoFoG, CNRS, CIRAD, INRAE, AgroParisTech, Université des Antilles, Université de Guyane, 97310 Kourou, France
| |
Collapse
|
12
|
Munjal A, Hannezo E, Tsai TY, Mitchison TJ, Megason SG. Extracellular hyaluronate pressure shaped by cellular tethers drives tissue morphogenesis. Cell 2021; 184:6313-6325.e18. [PMID: 34942099 DOI: 10.1016/j.cell.2021.11.025] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 09/29/2021] [Accepted: 11/15/2021] [Indexed: 12/24/2022]
Abstract
How tissues acquire complex shapes is a fundamental question in biology and regenerative medicine. Zebrafish semicircular canals form from invaginations in the otic epithelium (buds) that extend and fuse to form the hubs of each canal. We find that conventional actomyosin-driven behaviors are not required. Instead, local secretion of hyaluronan, made by the enzymes uridine 5'-diphosphate dehydrogenase (ugdh) and hyaluronan synthase 3 (has3), drives canal morphogenesis. Charged hyaluronate polymers osmotically swell with water and generate isotropic extracellular pressure to deform the overlying epithelium into buds. The mechanical anisotropy needed to shape buds into tubes is conferred by a polarized distribution of actomyosin and E-cadherin-rich membrane tethers, which we term cytocinches. Most work on tissue morphogenesis ascribes actomyosin contractility as the driving force, while the extracellular matrix shapes tissues through differential stiffness. Our work inverts this expectation. Hyaluronate pressure shaped by anisotropic tissue stiffness may be a widespread mechanism for powering morphological change in organogenesis and tissue engineering.
Collapse
|
13
|
Stinziano JR, Roback C, Sargent D, Murphy BK, Hudson PJ, Muir CD. Principles of resilient coding for plant ecophysiologists. AoB Plants 2021; 13:plab059. [PMID: 34646435 PMCID: PMC8501907 DOI: 10.1093/aobpla/plab059] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 09/15/2021] [Indexed: 06/02/2023]
Abstract
Plant ecophysiology is founded on a rich body of physical and chemical theory, but it is challenging to connect theory with data in unambiguous, analytically rigorous and reproducible ways. Custom scripts written in computer programming languages (coding) enable plant ecophysiologists to model plant processes and fit models to data reproducibly using advanced statistical techniques. Since many ecophysiologists lack formal programming education, we have yet to adopt a unified set of coding principles and standards that could make coding easier to learn, use and modify. We identify eight principles to help in plant ecophysiologists without much programming experience to write resilient code: (i) standardized nomenclature, (ii) consistency in style, (iii) increased modularity/extensibility for easier editing and understanding, (iv) code scalability for application to large data sets, (v) documented contingencies for code maintenance, (vi) documentation to facilitate user understanding; (vii) extensive tutorials and (viii) unit testing and benchmarking. We illustrate these principles using a new R package, {photosynthesis}, which provides a set of analytical and simulation tools for plant ecophysiology. Our goal with these principles is to advance scientific discovery in plant ecophysiology by making it easier to use code for simulation and data analysis, reproduce results and rapidly incorporate new biological understanding and analytical tools.
Collapse
Affiliation(s)
- Jospeh R Stinziano
- Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Cassaundra Roback
- Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Demi Sargent
- Hawkesbury Institute for the Environment, Western Sydney University, Sydney 2753, Australia
| | - Bridget K Murphy
- Department of Biology, University of Toronto, Mississauga L5L 1C6, Canada
| | - Patrick J Hudson
- Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA
| | | |
Collapse
|
14
|
Pritzkow C, Szota C, Williamson V, Arndt SK. Previous drought exposure leads to greater drought resistance in eucalypts through changes in morphology rather than physiology. Tree Physiol 2021; 41:1186-1198. [PMID: 33530102 DOI: 10.1093/treephys/tpaa176] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 12/22/2020] [Indexed: 06/12/2023]
Abstract
Over their lifetime, trees are repeatedly exposed to droughts. It is therefore important to understand whether repeated drought exposure makes trees more or less drought tolerant. Here, we investigated the effect of repeated droughts on functional trait expression and tree function in Eucalyptus obliqua. Further, we tested whether previous drought exposure enabled trees to avoid leaf death for longer under a subsequent severe drought. Trees were subjected for 1 year to 2 drought-rewatering cycles (drought treatment) or well-watered conditions, before imposing a severe drought. Trees in the drought treatment reduced their overall leaf area and biomass, whereas leaf-level anatomical, morphological and physiological traits remained mostly unaffected. There were no differences in water potential at the turgor loss point, leaf xylem vulnerability to embolism, leaf size, maximum xylem vessel diameter or cell wall thickness between treatments after the conditioning period. When exposed to a subsequent severe drought, trees previously exposed to drought were more drought tolerant due to a lower water potential at leaf death and tree-level morphological rather than physiological adjustments. Trees previously exposed to drought were smaller and used less water, which delayed leaf death for 39 days compared with 22 days for the well-watered trees. Our study indicates that previous drought exposure can facilitate tree-level morphological adjustment, which potentially enhances survival of E. obliqua trees during subsequent drought events.
Collapse
Affiliation(s)
- Carola Pritzkow
- School of Ecosystem and Forest Sciences, University of Melbourne, 500 Yarra Blvd, Burnley, VIC, 3121, Australia
- School of Biology, University of Tasmania, 55 Private Bag, Hobart, TAS, 7001, Australia
| | - Christopher Szota
- School of Ecosystem and Forest Sciences, University of Melbourne, 500 Yarra Blvd, Burnley, VIC, 3121, Australia
| | - Virginia Williamson
- School of Ecosystem and Forest Sciences, University of Melbourne, 500 Yarra Blvd, Burnley, VIC, 3121, Australia
| | - Stefan K Arndt
- School of Ecosystem and Forest Sciences, University of Melbourne, 500 Yarra Blvd, Burnley, VIC, 3121, Australia
| |
Collapse
|
15
|
De Bartolo S, Vittorio M, Francone A, Guido F, Leone E, Mastronardi VM, Notaro A, Tomasicchio GR. Direct Scaling of Measure on Vortex Shedding through a Flapping Flag Device in the Open Channel around a Cylinder at Re∼10 3: Taylor's Law Approach. Sensors (Basel) 2021; 21:1871. [PMID: 33800140 DOI: 10.3390/s21051871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 02/17/2021] [Accepted: 03/03/2021] [Indexed: 11/18/2022]
Abstract
The problem of vortex shedding, which occurs when an obstacle is placed in a regular flow, is governed by Reynolds and Strouhal numbers, known by dimensional analysis. The present work aims to propose a thin films-based device, consisting of an elastic piezoelectric flapping flag clamped at one end, in order to determine the frequency of vortex shedding downstream an obstacle for a flow field at Reynolds number Re∼103 in the open channel. For these values, Strouhal number obtained in such way is in accordance with the results known in literature. Moreover, the development of the voltage over time, generated by the flapping flag under the load due to flow field, shows a highly fluctuating behavior and satisfies Taylor’s law, observed in several complex systems. This provided useful information about the flow field through the constitutive law of the device.
Collapse
|
16
|
Göttler C, Elflein K, Siegwart R, Sitti M. Spider Origami: Folding Principle of Jumping Spider Leg Joints for Bioinspired Fluidic Actuators. Adv Sci (Weinh) 2021; 8:2003890. [PMID: 33717859 PMCID: PMC7927609 DOI: 10.1002/advs.202003890] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 11/18/2020] [Indexed: 05/23/2023]
Abstract
Jumping spiders (Phidippus regius) are known for their ability to traverse various terrains and have targeted jumps within the fraction of a second to catch flying preys. Different from humans and insects, spiders use muscles to flex their legs, and hydraulic actuation for extension. By pressurizing their inner body fluid, they can achieve fast leg extensions for running and jumping. Here, the working principle of the articular membrane covering the spider leg joint pit is investigated. This membrane is highly involved in walking, grasping, and jumping motions. Hardness and stiffness of the articular membrane is studied using nanoindentation tests and preparation methods for scanning electron microscopy and histology are developed to give detailed information about the inner and outer structure of the leg joint and its membrane. Inspired by the stroller umbrella-like folding mechanism of the articular membrane, a robust thermoplastic polyurethane-based rotary semifluidic actuator is demonstrated, which shows increased durability, achieves working angles over 120°, produces high torques which allows lifts over 100 times of its own weight and jumping abilities. The developed actuator can be used for future grasping tasks, safe human-robot interactions and multilocomotion ground robot applications, and it can shed light into spider locomotion-related questions.
Collapse
Affiliation(s)
- Chantal Göttler
- Physical Intelligence DepartmentMax Planck Institute for Intelligent SystemsStuttgart70569Germany
- Autonomous Systems LaboratoryETH ZurichZürich8092Switzerland
| | - Karin Elflein
- Physical Intelligence DepartmentMax Planck Institute for Intelligent SystemsStuttgart70569Germany
| | - Roland Siegwart
- Autonomous Systems LaboratoryETH ZurichZürich8092Switzerland
| | - Metin Sitti
- Physical Intelligence DepartmentMax Planck Institute for Intelligent SystemsStuttgart70569Germany
- Institute for Biomedical EngineeringETH ZurichZürich8092Switzerland
| |
Collapse
|
17
|
Sivasakthi K, Tharanya M, Zaman-Allah M, Kholová J, Thirunalasundari T, Vadez V. Transpiration difference under high evaporative demand in chickpea (Cicer arietinum L.) may be explained by differences in the water transport pathway in the root cylinder. Plant Biol (Stuttg) 2020; 22:769-780. [PMID: 32558986 DOI: 10.1111/plb.13147] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 06/04/2020] [Indexed: 05/24/2023]
Abstract
Terminal drought substantially reduces chickpea yield. Reducing water use at vegetative stage by reducing transpiration under high vapor pressure deficit (VPD), i.e. under dry/hot conditions, contributes to drought adaptation. We hypothesized that this trait could relate to differences in a genotype's dependence on root water transport pathways and hydraulics. Transpiration rate responses in conservative and profligate chickpea genotypes were evaluated under increasing VPD in the presence/absence of apoplastic and cell-to-cell transport inhibitors. Conservative genotypes ICC 4958 and ICC 8058 restricted transpiration under high VPD compared to the profligate genotypes ICC 14799 and ICC 867. Profligate genotypes were more affected by aquaporin inhibition of the cell-to-cell pathway than conservative genotypes, as measured by the root hydraulic conductance and transpiration under high VPD. Aquaporin inhibitor treatment also led to a larger reduction in root hydraulic conductivity in profligate than in conservative genotypes. In contrast, blockage of the apoplastic pathway in roots decreased transpiration more in conservative than in profligate genotypes. Interestingly, conservative genotypes had high early vigour, whereas profligate genotypes had low early vigour. In conclusion, profligate genotypes depend more on the cell-to-cell pathway, which might explain their higher root hydraulic conductivity, whereas water-saving by restricting transpiration led to higher dependence on the apoplastic pathway. This opens the possibility to screen for conservative or profligate chickpea phenotypes using inhibitors, itself opening to the search of the genetic basis of these differences.
Collapse
Affiliation(s)
- K Sivasakthi
- Crop Physiology Laboratory, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, Telangana, India
- Department of Industrial Biotechnology, Bharathidasan University, Tiruchirappalli, Tamilnadu, India
| | - M Tharanya
- Crop Physiology Laboratory, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, Telangana, India
- Department of Industrial Biotechnology, Bharathidasan University, Tiruchirappalli, Tamilnadu, India
| | - M Zaman-Allah
- International Center for Maize and Wheat Improvement (CIMMYT), Mount Pleasant Harare, Zimbabwe
| | - J Kholová
- Crop Physiology Laboratory, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, Telangana, India
| | - T Thirunalasundari
- Department of Industrial Biotechnology, Bharathidasan University, Tiruchirappalli, Tamilnadu, India
| | - V Vadez
- Crop Physiology Laboratory, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, Telangana, India
- IRD (Institut de Recherche pour le Developpement) - Univ. Montpellier - UMR DIADE, Montpellier cedex 5, France
| |
Collapse
|
18
|
Resco de Dios V, Arteaga C, Peguero-Pina JJ, Sancho-Knapik D, Qin H, Zveushe OK, Sun W, Williams DG, Boer MM, Voltas J, Moreno JM, Tissue DT, Gil-Pelegrín E. Hydraulic and photosynthetic limitations prevail over root non-structural carbohydrate reserves as drivers of resprouting in two Mediterranean oaks. Plant Cell Environ 2020; 43:1944-1957. [PMID: 32394490 DOI: 10.1111/pce.13781] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 05/04/2020] [Indexed: 05/16/2023]
Abstract
Resprouting is an ancestral trait in angiosperms that confers resilience after perturbations. As climate change increases stress, resprouting vigor is declining in many forest regions, but the underlying mechanism is poorly understood. Resprouting in woody plants is thought to be primarily limited by the availability of non-structural carbohydrate reserves (NSC), but hydraulic limitations could also be important. We conducted a multifactorial experiment with two levels of light (ambient, 2-3% of ambient) and three levels of water stress (0, 50 and 80 percent losses of hydraulic conductivity, PLC) on two Mediterranean oaks (Quercus ilex and Q. faginea) under a rain-out shelter (n = 360). The proportion of resprouting individuals after canopy clipping declined markedly as PLC increased for both species. NSC concentrations affected the response of Q. ilex, the species with higher leaf construction costs, and its effect depended on the PLC. The growth of resprouting individuals was largely dependent on photosynthetic rates for both species, while stored NSC availability and hydraulic limitations played minor and non-significant roles, respectively. Contrary to conventional wisdom, our results indicate that resprouting in oaks may be primarily driven by complex interactions between hydraulics and carbon sources, whereas stored NSC play a significant but secondary role.
Collapse
Affiliation(s)
- Víctor Resco de Dios
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, China
- Joint Research Unit CTFC-AGROTECNIO, Universitat de Lleida, Lleida, Spain
| | - Carles Arteaga
- Department of Crop and Forest Sciences, University of Lleida, Lleida, Spain
| | - José Javier Peguero-Pina
- Unidad de Recursos Forestales, Centro de Investigación y Tecnología Agroalimentaria de Aragón, Gobierno de Aragón, Zaragoza, Spain
| | - Domingo Sancho-Knapik
- Unidad de Recursos Forestales, Centro de Investigación y Tecnología Agroalimentaria de Aragón, Gobierno de Aragón, Zaragoza, Spain
| | - Haiyan Qin
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, China
| | - Obey K Zveushe
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, China
| | - Wei Sun
- Key Laboratory of Vegetation Ecology, Ministry of Education, Institute of Grassland Science, Northeast Normal University, Changchun, China
| | - David G Williams
- Department of Botany, University of Wyoming, Laramie, Wyoming, USA
| | - Matthias M Boer
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia
| | - Jordi Voltas
- Joint Research Unit CTFC-AGROTECNIO, Universitat de Lleida, Lleida, Spain
- Department of Crop and Forest Sciences, University of Lleida, Lleida, Spain
| | - José M Moreno
- Department of Environmental Sciences, University of Castilla-La Mancha, Toledo, Spain
| | - David T Tissue
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia
| | - Eustaquio Gil-Pelegrín
- Unidad de Recursos Forestales, Centro de Investigación y Tecnología Agroalimentaria de Aragón, Gobierno de Aragón, Zaragoza, Spain
| |
Collapse
|
19
|
Lindenroth L, Housden RJ, Wang S, Back J, Rhode K, Liu H. Design and Integration of a Parallel, Soft Robotic End-Effector for Extracorporeal Ultrasound. IEEE Trans Biomed Eng 2020; 67:2215-2229. [PMID: 31804926 PMCID: PMC7115900 DOI: 10.1109/tbme.2019.2957609] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVE In this work we address limitations in state-of-the-art ultrasound robots by designing and integrating a novel soft robotic system for ultrasound imaging. It employs the inherent qualities of soft fluidic actuators to establish safe, adaptable interaction between ultrasound probe and patient. METHODS We acquire clinical data to determine the movement ranges and force levels required in prenatal foetal ultrasound imaging and design the soft robotic end-effector accordingly. We verify its mechanical characteristics, derive and validate a kinetostatic model and demonstrate controllability and imaging capabilities on an ultrasound phantom. RESULTS The soft robot exhibits the desired stiffness characteristics and is able to reach 100% of the required workspace when no external force is present, and 95% of the workspace when considering its compliance. The model can accurately predict the end-effector pose with a mean error of 1.18±0.29 mm in position and 0.92±0.47° in orientation. The derived controller is, with an average position error of 0.39 mm, able to track a target pose efficiently without and with externally applied loads. Ultrasound images acquired with the system are of equally good quality compared to a manual sonographer scan. CONCLUSION The system is able to withstand loads commonly applied during foetal ultrasound scans and remains controllable with a motion range similar to manual scanning. SIGNIFICANCE The proposed soft robot presents a safe, cost-effective solution to offloading sonographers in day-to-day scanning routines. The design and modelling paradigms are greatly generalizable and particularly suitable for designing soft robots for physical interaction tasks.
Collapse
|
20
|
Wang Y, Sperry JS, Anderegg WRL, Venturas MD, Trugman AT. A theoretical and empirical assessment of stomatal optimization modeling. New Phytol 2020; 227:311-325. [PMID: 32248532 DOI: 10.1111/nph.16572] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 03/09/2020] [Indexed: 05/13/2023]
Abstract
Optimal stomatal control models have shown great potential in predicting stomatal behavior and improving carbon cycle modeling. Basic stomatal optimality theory posits that stomatal regulation maximizes the carbon gain relative to a penalty of stomatal opening. All models take a similar approach to calculate instantaneous carbon gain from stomatal opening (the gain function). Where the models diverge is in how they calculate the corresponding penalty (the penalty function). In this review, we compare and evaluate 10 different optimization models in how they quantify the penalty and how well they predict stomatal responses to the environment. We evaluate models in two ways. First, we compare their penalty functions against seven criteria that ensure a unique and qualitatively realistic solution. Second, we quantitatively test model against multiple leaf gas-exchange datasets. The optimization models with better predictive skills have penalty functions that meet our seven criteria and use fitting parameters that are both few in number and physiology based. The most skilled models are those with a penalty function based on stress-induced hydraulic failure. We conclude by proposing a new model that has a hydraulics-based penalty function that meets all seven criteria and demonstrates a highly predictive skill against our test datasets.
Collapse
Affiliation(s)
- Yujie Wang
- School of Biological Sciences, University of Utah, Salt Lake City, UT, 84112, USA
| | - John S Sperry
- School of Biological Sciences, University of Utah, Salt Lake City, UT, 84112, USA
| | - William R L Anderegg
- School of Biological Sciences, University of Utah, Salt Lake City, UT, 84112, USA
| | - Martin D Venturas
- School of Biological Sciences, University of Utah, Salt Lake City, UT, 84112, USA
| | - Anna T Trugman
- Department of Geography, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| |
Collapse
|
21
|
Du Q, Jiao X, Song X, Zhang J, Bai P, Ding J, Li J. The Response of Water Dynamics to Long-Term High Vapor Pressure Deficit Is Mediated by Anatomical Adaptations in Plants. Front Plant Sci 2020; 11:758. [PMID: 32582267 PMCID: PMC7289962 DOI: 10.3389/fpls.2020.00758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 05/12/2020] [Indexed: 06/11/2023]
Abstract
Vapor pressure deficit (VPD) is the driver of water movement in plants. However, little is known about how anatomical adaptations determine the acclimation of plant water dynamics to elevated VPD, especially at the whole plant level. Here, we examined the responses of transpiration, stomatal conductance (gs), hydraulic partitioning, and anatomical traits in two tomato cultivars (Jinpeng and Zhongza) to long-term high (2.2-2.6 kPa) and low (1.1-1.5 kPa) VPD. Compared to plants growing under low VPD, no variation in gs was found for Jinpeng under high VPD conditions; however, high VPD induced an increase in whole plant hydraulic conductance (Kplant), which was responsible for the maintenance of high transpiration. In contrast, transpiration was not influenced by high VPD in Zhongza, which was primarily attributed to a coordinated decline in gs and Kplant. The changes in gs were closely related to stomatal density and size. Furthermore, high VPD altered hydraulic partitioning among the leaf, stem, and root for both cultivars via adjustments in anatomy. The increase in lumen area of vessels in veins and large roots in Jinpeng under high VPD conditions improved water transport efficiency in the leaf and root, thus resulting in a high Kplant. However, the decreased Kplant for Zhongza under high VPD was the result of a decline of water transport efficiency in the leaf that was caused by a reduction in vein density. Overall, we concluded that the tradeoff in anatomical acclimations among plant tissues results in different water relations in plants under high VPD conditions.
Collapse
Affiliation(s)
- Qingjie Du
- College of Horticulture, Northwest A&F University, Yangling, China
- College of Horticulture, Henan Agricultural University, Zhengzhou, China
| | - Xiaocong Jiao
- College of Horticulture, Northwest A&F University, Yangling, China
| | - Xiaoming Song
- College of Horticulture, Northwest A&F University, Yangling, China
| | - Jiayu Zhang
- College of Horticulture, Northwest A&F University, Yangling, China
| | - Ping Bai
- College of Horticulture, Northwest A&F University, Yangling, China
| | - Juping Ding
- College of Horticulture, Northwest A&F University, Yangling, China
| | - Jianming Li
- College of Horticulture, Northwest A&F University, Yangling, China
| |
Collapse
|
22
|
Browne M, Yardimci NT, Scoffoni C, Jarrahi M, Sack L. Prediction of leaf water potential and relative water content using terahertz radiation spectroscopy. Plant Direct 2020; 4:e00197. [PMID: 32313868 PMCID: PMC7164375 DOI: 10.1002/pld3.197] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 12/03/2019] [Indexed: 05/02/2023]
Abstract
Increases in the frequency and severity of droughts across many regions worldwide necessitate an improved capacity to determine the water status of plants at organ, whole plant, canopy, and regional scales. Noninvasive methods have most potential for simultaneously improving basic water relations research and ground-, flight-, and space-based sensing of water status, with applications in sustainability, food security, and conservation. The most frequently used methods to measure the most salient proxies of plant water status, that is, water mass per leaf area (WMA), relative water content (RWC), and leaf water potential (Ψleaf), require the excision of tissues and laboratory analysis, and have thus been limited to relatively low throughput and small study scales. Applications using electromagnetic radiation in the visible, infrared, and terahertz ranges can resolve the water status of canopies, yet heretofore have typically focused on statistical approaches to estimating RWC for leaves before and after severe dehydration, and few have predicted Ψleaf. Terahertz radiation has great promise to estimate leaf water status across the range of leaf dehydration important for the control of gas exchange and leaf survival. We demonstrate a refined method and physical model to predict WMA, RWC, and Ψleaf from terahertz transmission across a wide range of levels of dehydration for given leaves of three species, as well as across leaves of given species and across multiple species. These findings highlight the powerful potential and the outstanding challenges in applying in vivo terahertz spectrometry as a remote sensor of water status for a range of applications.
Collapse
Affiliation(s)
- Marvin Browne
- Department of Ecology and Evolutionary BiologyUniversity of California Los AngelesLos AngelesCAUSA
| | - Nezih Tolga Yardimci
- Department of Electrical and Computer EngineeringUniversity of California Los Angeles, Los AngelesCA Los AngelesCAUSA
| | - Christine Scoffoni
- Department of Biological SciencesCalifornia State University, Los AngelesLos AngelesCAUSA
| | - Mona Jarrahi
- Department of Electrical and Computer EngineeringUniversity of California Los Angeles, Los AngelesCA Los AngelesCAUSA
| | - Lawren Sack
- Department of Ecology and Evolutionary BiologyUniversity of California Los AngelesLos AngelesCAUSA
| |
Collapse
|
23
|
Swedan NH. Parameterization of energy cycles between the hemispheres. Sci Prog 2020; 103:36850420922773. [PMID: 32519922 PMCID: PMC10364954 DOI: 10.1177/0036850420922773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/11/2023]
Abstract
Seasonal variations in the temperatures of the hemispheres induce seasonal energy cycles between the hemispheres that drive tropical cyclones. Because the northern hemisphere has warmed more than the southern hemisphere, climate energy cycles develop between the hemispheres as well. The seasonal and climate energy cycles appear to interact among themselves, and tropical cyclone counts are affected by these interactions. Furthermore, the total number of tropical cyclones appears to have an increasing trend. The annual energy of tropical cyclones is nearly 1.46 × 1022 J yr-1, and climate cycle energy is between 4.0 and 6.6 × 1021 J per cycle. The magnitude of the climate energy cycles is thus large enough to alter the energy and frequency of the tropical cyclones. Given that the climate is changing, the energy and frequency of tropical cyclones may be changing as well. The subject is broad and this work is limited to parameterization of the physics of energy oscillations between the hemispheres, demonstrating the existence of climate energy cycles, and revealing interactions between climate and seasonal energy cycles. Also, this parameterization may assist researchers in obtaining more and coordinated data relative to these cycles.
Collapse
|
24
|
Creek D, Lamarque LJ, Torres-Ruiz JM, Parise C, Burlett R, Tissue DT, Delzon S. Xylem embolism in leaves does not occur with open stomata: evidence from direct observations using the optical visualization technique. J Exp Bot 2020; 71:1151-1159. [PMID: 31641746 DOI: 10.1093/jxb/erz474] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Accepted: 10/11/2019] [Indexed: 06/10/2023]
Abstract
Drought represents a major abiotic constraint to plant growth and survival. On the one hand, plants keep stomata open for efficient carbon assimilation while, on the other hand, they close them to prevent permanent hydraulic impairment from xylem embolism. The order of occurrence of these two processes (stomatal closure and the onset of leaf embolism) during plant dehydration has remained controversial, largely due to methodological limitations. However, the newly developed optical visualization method now allows concurrent monitoring of stomatal behaviour and leaf embolism formation in intact plants. We used this new approach directly by dehydrating intact saplings of three contrasting tree species and indirectly by conducting a literature survey across a greater range of plant taxa. Our results indicate that increasing water stress generates the onset of leaf embolism consistently after stomatal closure, and that the lag time between these processes (i.e. the safety margin) rises with increasing embolism resistance. This suggests that during water stress, embolism-mediated declines in leaf hydraulic conductivity are unlikely to act as a signal for stomatal down-regulation. Instead, these species converge towards a strategy of closing stomata early to prevent water loss and delay catastrophic xylem dysfunction.
Collapse
Affiliation(s)
- Danielle Creek
- Université Clermont-Auvergne, INRA, PIAF, Clermont-Ferrand, France
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | | | | | | | - Regis Burlett
- BIOGECO, INRA, Université de Bordeaux, Pessac, France
| | - David T Tissue
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | | |
Collapse
|
25
|
Pratt RB, Castro V, Fickle JC, Jacobsen AL. Embolism resistance of different aged stems of a California oak species (Quercus douglasii): optical and microCT methods differ from the benchtop-dehydration standard. Tree Physiol 2020; 40:5-18. [PMID: 31553460 DOI: 10.1093/treephys/tpz092] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Revised: 07/30/2019] [Accepted: 08/15/2019] [Indexed: 06/10/2023]
Abstract
Vulnerability of xylem to embolism is an important trait related to drought resistance of plants. Methods continue to be developed and debated for measuring embolism. We tested three methods (benchtop dehydration/hydraulic, micro-computed tomography (microCT) and optical) for assessing the vulnerability to embolism of a native California oak species (Quercus douglasii Hook. & Arn.), including an analysis of three different stem ages. All three methods were found to significantly differ in their estimates, with a greater resistance to embolism as follows: microCT > optical > hydraulic. Careful testing was conducted for the hydraulic method to evaluate multiple known potential artifacts, and none was found. One-year-old stems were more resistant than older stems using microCT and optical methods, but not hydraulic methods. Divergence between the microCT and optical methods from the standard hydraulic method was consistent with predictions based on known errors when estimating theoretical losses in hydraulic function in both microCT and optical methods. When the goal of a study is to describe or predict losses in hydraulic conductivity, neither the microCT nor optical methods are reliable for accurately constructing vulnerability curves of stems; nevertheless, these methods may be useful if the goal of a study is to identify embolism events irrespective of hydraulic conductivity or hydraulic function.
Collapse
Affiliation(s)
- R Brandon Pratt
- Department of Biology, California State University, Bakersfield, 9001 Stockdale Hwy, Bakersfield, CA
| | - Viridiana Castro
- Department of Biology, California State University, Bakersfield, 9001 Stockdale Hwy, Bakersfield, CA
| | - Jaycie C Fickle
- Department of Biology, California State University, Bakersfield, 9001 Stockdale Hwy, Bakersfield, CA
| | - Anna L Jacobsen
- Department of Biology, California State University, Bakersfield, 9001 Stockdale Hwy, Bakersfield, CA
| |
Collapse
|
26
|
Rodriguez-Dominguez CM, Brodribb TJ. Declining root water transport drives stomatal closure in olive under moderate water stress. New Phytol 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] [What about the content of this article? (0)] [Affiliation(s)] [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.
Collapse
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
| |
Collapse
|
27
|
Mackay DS, Savoy PR, Grossiord C, Tai X, Pleban JR, Wang DR, McDowell NG, Adams HD, Sperry JS. Conifers depend on established roots during drought: results from a coupled model of carbon allocation and hydraulics. New Phytol 2020; 225:679-692. [PMID: 31276231 DOI: 10.1111/nph.16043] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 07/01/2019] [Indexed: 06/09/2023]
Abstract
Trees may survive prolonged droughts by shifting water uptake to reliable water sources, but it is unknown if the dominant mechanism involves activating existing roots or growing new roots during drought, or some combination of the two. To gain mechanistic insights on this unknown, a dynamic root-hydraulic modeling framework was developed that set up a feedback between hydraulic controls over carbon allocation and the role of root growth on soil-plant hydraulics. The new model was tested using a 5 yr drought/heat field experiment on an established piñon-juniper stand with root access to bedrock groundwater. Owing to the high carbon cost per unit root area, modeled trees initialized without adequate bedrock groundwater access experienced potentially lethal declines in water potential, while all of the experimental trees maintained nonlethal water potentials. Simulated trees were unable to grow roots rapidly enough to mediate the hydraulic stress, particularly during warm droughts. Alternatively, modeled trees initiated with root access to bedrock groundwater matched the hydraulics of the experimental trees by increasing their water uptake from bedrock groundwater when soil layers dried out. Therefore, the modeling framework identified a critical mechanism for drought response that required trees to shift water uptake among existing roots rather than growing new roots.
Collapse
Affiliation(s)
- D Scott Mackay
- Department of Geography, University at Buffalo, Buffalo, NY, 14261, USA
| | - Philip R Savoy
- Department of Biology, Duke University, Durham, NC, 27708, USA
| | - Charlotte Grossiord
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903, Birmensdorf, Switzerland
| | - Xiaonan Tai
- Department of Geography, University at Buffalo, Buffalo, NY, 14261, USA
| | - Jonathan R Pleban
- Department of Geography, University at Buffalo, Buffalo, NY, 14261, USA
| | - Diane R Wang
- Department of Geography, University at Buffalo, Buffalo, NY, 14261, USA
| | | | - Henry D Adams
- Department of Plant Biology, Ecology, and Evolution, Oklahoma State University, Stillwater, OK, 74078, USA
| | - John S Sperry
- Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA
| |
Collapse
|
28
|
Timothy J. Brodribb. New Phytol 2019; 224:568-9. [PMID: 31545887 DOI: 10.1111/nph.16097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
|
29
|
Wason JW, Brodersen CR, Huggett BA. The functional implications of tracheary connections across growth rings in four northern hardwood trees. Ann Bot 2019; 124:297-306. [PMID: 31330537 PMCID: PMC6758585 DOI: 10.1093/aob/mcz076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 05/02/2019] [Indexed: 05/06/2023]
Abstract
BACKGROUND AND AIMS Deciduous angiosperm trees transport xylem sap through trunks and branches in vessels within annual growth rings. Utilizing previous growth rings for sap transport could increase vessel network size and redundancy but may expose new xylem to residual air embolisms in the network. Despite the important role of vessel networks in sap transport and drought resistance, our understanding of cross-ring connections within and between species is limited. METHODS We studied cross-ring connections in four temperate deciduous trees using dye staining and X-ray microcomputed tomography (microCT) to detect xylem connectivity across growth rings and quantify their impact on hydraulic conductivity. KEY RESULTS Acer rubrum and Fraxinus americana had cross-ring connections visible in microCT but only A. rubrum used previous growth rings for axial sap flow. Fagus grandifolia and Quercus rubra, however, did not have cross-ring connections. Accounting for the number of growth rings that function for axial transport improved hydraulic conductivity estimates. CONCLUSIONS These data suggest that the presence of cross-ring connections may help explain aspects of whole-tree xylem sap transport and should be considered for plant hydraulics measurements in these species and others with similar anatomy.
Collapse
Affiliation(s)
- Jay W Wason
- School of Forest Resources, University of Maine, Orono, ME, USA
- School of Forestry and Environmental Studies, Yale University, New Haven, CT, USA
- For correspondence. E-mail
| | - Craig R Brodersen
- School of Forestry and Environmental Studies, Yale University, New Haven, CT, USA
| | | |
Collapse
|
30
|
Quirk J, Bellasio C, Johnson DA, Beerling DJ. Response of photosynthesis, growth and water relations of a savannah-adapted tree and grass grown across high to low CO2. Ann Bot 2019; 124:77-90. [PMID: 31008510 PMCID: PMC6676382 DOI: 10.1093/aob/mcz048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 04/08/2019] [Indexed: 05/12/2023]
Abstract
BACKGROUND AND AIMS By the year 2100, atmospheric CO2 concentration ([CO2]a) could reach 800 ppm, having risen from ~200 ppm since the Neogene, beginning ~24 Myr ago. Changing [CO2]a affects plant carbon-water balance, with implications for growth, drought tolerance and vegetation shifts. The evolution of C4 photosynthesis improved plant hydraulic function under low [CO2]a and preluded the establishment of savannahs, characterized by rapid transitions between open C4-dominated grassland with scattered trees and closed forest. Understanding directional vegetation trends in response to environmental change will require modelling. But models are often parameterized with characteristics observed in plants under current climatic conditions, necessitating experimental quantification of the mechanistic underpinnings of plant acclimation to [CO2]a. METHODS We measured growth, photosynthesis and plant-water relations, within wetting-drying cycles, of a C3 tree (Vachellia karroo, an acacia) and a C4 grass (Eragrostis curvula) grown at 200, 400 or 800 ppm [CO2]a. We investigated the mechanistic linkages between trait responses to [CO2]a under moderate soil drying, and photosynthetic characteristics. KEY RESULTS For V. karroo, higher [CO2]a increased assimilation, foliar carbon:nitrogen, biomass and leaf starch, but decreased stomatal conductance and root starch. For Eragrostis, higher [CO2]a decreased C:N, did not affect assimilation, biomass or starch, and markedly decreased stomatal conductance. Together, this meant that C4 advantages in efficient water-use over the tree were maintained with rising [CO2]a. CONCLUSIONS Acacia and Eragrostis acclimated differently to [CO2]a, with implications for their respective responses to water limitation and environmental change. Our findings question the carbon-centric focus on factors limiting assimilation with changing [CO2]a, how they are predicted and their role in determining productivity. We emphasize the continuing importance of water-conserving strategies in the assimilation response of savannah plants to rising [CO2]a.
Collapse
Affiliation(s)
- Joe Quirk
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK
| | - Chandra Bellasio
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK
- University of the Balearic Islands, Palma, Illes Balears, Spain
- Research School of Biology, Australian National University, Acton, ACT, Australia
- Trees and Timber Institute, National Research Council of Italy, Sesto Fiorentino, Florence, Italy
| | - David A Johnson
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK
| | - David J Beerling
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK
| |
Collapse
|
31
|
Condo TK, Reinhardt K. Large variation in branch and branch-tip hydraulic functional traits in Douglas-fir (Pseudotsuga menziesii) approaching lower treeline. Tree Physiol 2019; 39:1461-1472. [PMID: 31135912 DOI: 10.1093/treephys/tpz058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 04/29/2019] [Accepted: 05/13/2019] [Indexed: 06/09/2023]
Abstract
Few studies have quantified intraspecific variation of hydraulic functional traits in conifers across elevation gradients that include range boundaries. In the Intermountain West, USA, the lower elevational limit of forests (lower treeline) is generally assumed to be caused by water limitations to growth and water relations, yet few studies directly show this. To test this assumption, we measured changes in a suite of traits that characterize drought tolerance such as drought-induced hydraulic vulnerability, hydraulic transport capacity and morphological traits in branch tips and branches of Douglas-fir (Pseudotsuga menziesii var. glauca (Mirb.) Franco) along a 400-m elevation gradient in southeastern Idaho that included lower treeline. As elevation decreased, vulnerability to hydraulic dysfunction and maximum conductivity both decreased in branches; some hydraulic safety-efficiency trade-offs were evident. In branch tips, the water potential at the turgor loss point decreased, while maximum conductance increased with decreasing elevation, highlighting that branch-tip-level responses to less moisture availability accompanied by warmer temperatures might not be coordinated with branch responses. As the range boundary was approached, we did not observe non-linear changes in parameters among sites or increased variance within sites, which current ecological hypotheses on range limits suggest. Our results indicate that there is substantial plasticity in hydraulic functional traits in branch tips and branches of Douglas-fir, although the direction of the trends along the elevation gradient sometimes differed between organs. Such plasticity may mitigate the negative impacts of future drought on Douglas-fir productivity, slowing shifts in its range that are expected to occur with climate change.
Collapse
Affiliation(s)
- Theresa K Condo
- Department of Biological Sciences, Idaho State University, 921 S 8th Ave., Stop 8007, Pocatello, ID 83209, USA
| | - Keith Reinhardt
- Department of Biological Sciences, Idaho State University, 921 S 8th Ave., Stop 8007, Pocatello, ID 83209, USA
| |
Collapse
|
32
|
Roddy AB, Jiang GF, Cao K, Simonin KA, Brodersen CR. Hydraulic traits are more diverse in flowers than in leaves. New Phytol 2019; 223:193-203. [PMID: 30767230 DOI: 10.1111/nph.15749] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 02/11/2019] [Indexed: 06/09/2023]
Abstract
Maintaining water balance has been a critical constraint shaping the evolution of leaf form and function. However, flowers, which are heterotrophic and relatively short-lived, may not be constrained by the same physiological and developmental factors. We measured physiological parameters derived from pressure-volume curves for leaves and flowers of 22 species to characterize the diversity of hydraulic traits in flowers and to determine whether flowers are governed by the same constraints as leaves. Compared with leaves, flowers had high saturated water content, which was a strong predictor of hydraulic capacitance in both leaves and flowers. Principal component analysis revealed that flowers occupied a different region of multivariate trait space than leaves and that hydraulic traits are more diverse in flowers than in leaves. Without needing to maintain high rates of transpiration, flowers rely on other hydraulic traits, such as high hydraulic capacitance, to maintain turgor pressure. As a result, instead of employing a metabolically expensive but durable carbon (C)-based skeleton, flowers may rely predominantly on a metabolically cheaper, hydrostatic skeleton to keep their structures on display for pollinators, which has important implications for both the costs of reproduction and the biomechanical performance of flowers, particularly during drought.
Collapse
Affiliation(s)
- Adam B Roddy
- School of Forestry & Environmental Studies, Yale University, New Haven, CT, 06511, USA
| | - Guo-Feng Jiang
- State Key Laboratory of Conservation and Utilization of Subtropical Agrobioresources, Guangxi University, Nanning, Guangxi, 530004, China
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, 530004, China
| | - Kunfang Cao
- State Key Laboratory of Conservation and Utilization of Subtropical Agrobioresources, Guangxi University, Nanning, Guangxi, 530004, China
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, 530004, China
| | - Kevin A Simonin
- Department of Biology, San Francisco State University, San Francisco, CA, 94132, USA
| | - Craig R Brodersen
- School of Forestry & Environmental Studies, Yale University, New Haven, CT, 06511, USA
| |
Collapse
|
33
|
Boyce CK, Zwieniecki MA. The prospects for constraining productivity through time with the whole-plant physiology of fossils. New Phytol 2019; 223:40-49. [PMID: 30304562 DOI: 10.1111/nph.15446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 02/26/2018] [Indexed: 06/08/2023]
Abstract
Anatomically preserved fossils allow estimation of hydraulic parameters, potentially providing constraints on interpreting whole-plant physiology. However, different organ systems have typically been considered in isolation - a problem given common mismatches of high and low conductance components coupled in the hydraulic path of the same plant. A recent paper addressed the issue of how to handle resistance mismatches in fossil plant hydraulics, focusing on Carboniferous medullosan seed plants and arborescent lycopsids. Among other problems, however, a fundamental error was made: the transpiration stream consists of resistances in series (where resistances are additive and the component with the largest resistance can dominate the behavior of the system), but emphasis was instead placed on the lowest resistance, effectively treating the system as resistances in parallel (where the component with the smallest resistance will dominate the behavior). Instead of possessing high assimilation capacities to match high specific stem conductances, it is argued here that individual high conductance components in these Paleozoic plants are nonetheless associated with low whole-plant productivity, just as can be commonly seen in living plants. Resolution of how to handle these issues may have broad implications for the Earth system including geobiological feedbacks to rock weathering, atmospheric composition, and climate.
Collapse
Affiliation(s)
- C Kevin Boyce
- Geological Sciences, Stanford University, Stanford, CA, 94305, USA
| | | |
Collapse
|
34
|
Blackman CJ, Creek D, Maier C, Aspinwall MJ, Drake JE, Pfautsch S, O'Grady A, Delzon S, Medlyn BE, Tissue DT, Choat B. Drought response strategies and hydraulic traits contribute to mechanistic understanding of plant dry-down to hydraulic failure. Tree Physiol 2019; 39:910-924. [PMID: 30865274 DOI: 10.1093/treephys/tpz016] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 02/01/2019] [Indexed: 05/17/2023]
Abstract
Drought-induced tree mortality alters forest structure and function, yet our ability to predict when and how different species die during drought remains limited. Here, we explore how stomatal control and drought tolerance traits influence the duration of drought stress leading to critical levels of hydraulic failure. We examined the growth and physiological responses of four woody plant species (three angiosperms and one conifer) representing a range of water-use and drought tolerance traits over the course of two controlled drought-recovery cycles followed by an extended dry-down. At the end of the final dry-down phase, we measured changes in biomass ratios and leaf carbohydrates. During the first and second drought phases, plants of all species closed their stomata in response to decreasing water potential, but only the conifer species avoided water potentials associated with xylem embolism as a result of early stomatal closure relative to thresholds of hydraulic dysfunction. The time it took plants to reach critical levels of water stress during the final dry-down was similar among the angiosperms (ranging from 39 to 57 days to stemP88) and longer in the conifer (156 days to stemP50). Plant dry-down time was influenced by a number of factors including species stomatal-hydraulic safety margin (gsP90 - stemP50), as well as leaf succulence and minimum stomatal conductance. Leaf carbohydrate reserves (starch) were not depleted at the end of the final dry-down in any species, irrespective of the duration of drought. These findings highlight the need to consider multiple structural and functional traits when predicting the timing of hydraulic failure in plants.
Collapse
Affiliation(s)
- Chris J Blackman
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, Australia
| | - Danielle Creek
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, Australia
| | - Chelsea Maier
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, Australia
| | - Michael J Aspinwall
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, Australia
- Department of Biology, University of North Florida, 1 UNF Drive, Jacksonville, FL, USA
| | - John E Drake
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, Australia
- Forest and Natural Resources Management, SUNY-ESF, 1 Forestry Drive, Syracuse, NY, USA
| | - Sebastian Pfautsch
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, Australia
- School of Social Science and Psychology (Urban Studies), Western Sydney University, Locked Bag 1797, Penrith, NSW, Australia
| | | | | | - Belinda E Medlyn
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, Australia
| | - David T Tissue
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, Australia
| | - Brendan Choat
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, Australia
| |
Collapse
|
35
|
Yang D, Zhang YJ, Song J, Niu CY, Hao GY. Compound leaves are associated with high hydraulic conductance and photosynthetic capacity: evidence from trees in Northeast China. Tree Physiol 2019; 39:729-739. [PMID: 30668831 DOI: 10.1093/treephys/tpy147] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Revised: 12/08/2018] [Accepted: 12/19/2018] [Indexed: 06/09/2023]
Abstract
Characterizing differences in key functional traits between simple-leaved (SL) and compound-leaved (CL) tree species can contribute to a better understanding of the adaptive significance of compound leaf form. In particular, this information may provide a mechanistic explanation to the long-proposed fast-growth hypothesis of CL tree species. Here, using five SL and five CL tree species co-occurring in a typical temperate forest of Northeast China, we tested whether higher hydraulic efficiency underlies potentially high photosynthetic capacity in CL species. We found that the CL species had significantly higher hydraulic conductance at the whole-branch level than the SL species (0.52 ± 0.13 vs 0.15 ± 0.04 × 10-4 kg m-2 s-1 Pa-1, P = 0.029). No significant difference in net photosynthetic rate (14.7 ± 2.43 vs 12.5 ± 2.05 μmol m-2 s-1, P = 0.511) was detected between these two groups, but this was largely due to the existence of one outlier species in each of the two functional groups. Scrutinization of the intragroup variations in functional traits revealed that distinctions of the two outlier species in wood type (ring- vs diffuse-porous) from their respective functional groups have likely contributed to their aberrant physiological performances. The potentially high photosynthetic capacity of CL species seems to require ring-porous wood to achieve high hydraulic efficiency. Due to its limitation on leaf photosynthetic capacity, diffuse-porous wood with lower hydraulic conductivity largely precludes its combination with the 'throw-away' strategy (i.e., annually replacing the stem-like rachises) of compound-leaved tree species, which intrinsically requires high carbon assimilation rate to compensate for their extra carbon losses. Our results for the first time show clear differentiation in hydraulic architecture and CO2 assimilation between sympatric SL and CL species, which contributes to the probing of the underlying mechanism responsible for the potential fast growth of trees with compound leaves.
Collapse
Affiliation(s)
- Da Yang
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yong-Jiang Zhang
- School of Biology and Ecology, the University of Maine, Orono, ME, USA
| | - Jia Song
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Cun-Yang Niu
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Guang-You Hao
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
| |
Collapse
|
36
|
Tomasella M, Nardini A, Hesse BD, Machlet A, Matyssek R, Häberle KH. Close to the edge: effects of repeated severe drought on stem hydraulics and non-structural carbohydrates in European beech saplings. Tree Physiol 2019; 39:717-728. [PMID: 30668841 DOI: 10.1093/treephys/tpy142] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 11/30/2018] [Accepted: 12/12/2018] [Indexed: 05/11/2023]
Abstract
Severe drought events threaten tree water transport system, productivity and survival. Woody angiosperms generally die when embolism-induced loss of hydraulic conductance (PLC) surpasses 80-90% under intense water shortage. However, the recovery capability and possible long-term carry-over effects of repeated drought events could dictate the fate of species' population under climate change scenarios. Potted saplings of European beech (Fagus sylvatica L.) were subjected to two drought cycles in two consecutive growing seasons, aiming to induce minimum leaf water potentials (Ψmd) of about -4 MPa, corresponding to hydraulic thresholds for survival of this species. In the first cycle, a well-irrigated (C) and a drought-stressed group (S) were formed, and, in the following summer, each group was divided in a well-irrigated and a drought-stressed one (four groups in total). The impact of the multiple drought events was assessed by measuring wood anatomical traits, biomass production, water relations, stem hydraulics and non-structural carbohydrate (NSC) content. We also investigated possible connections between stem hydraulics and carbon dynamics during the second drought event and following re-irrigation. S plants had lower Ψmd and maximum specific hydraulic conductivity (Ks) than C plants in the following growing season. Additionally, aboveground biomass production and leaf number were lower compared to C trees, resulting in lower water consumption. However, PLC was similar between groups, probably due to the production of new functional xylem in spring. The second drought event induced 85% PLC and promoted conversion of starch-to soluble sugars. Nevertheless, 1 week after re-irrigation, no embolism repair was observed and soluble sugars were reconverted to starch. The previous drought cycle did not influence the hydraulic performance during the second drought, and after re-irrigation S plants had 40% higher wood NSC content. Our data suggest that beech cannot recover from high embolism levels but multiple droughts might enhance stem NSC availability.
Collapse
Affiliation(s)
- Martina Tomasella
- Department of Life Sciences, Università degli Studi di Trieste, Via L. Giorgieri 10, Trieste, Italy
- Department of Ecology and Ecosystem Management-Chair for Ecophysiology of Plants, Technische Universität München, Hans-Carl-von-Carlowitz Platz 2, Freising, Germany
| | - Andrea Nardini
- Department of Life Sciences, Università degli Studi di Trieste, Via L. Giorgieri 10, Trieste, Italy
| | - Benjamin D Hesse
- Department of Ecology and Ecosystem Management-Chair for Ecophysiology of Plants, Technische Universität München, Hans-Carl-von-Carlowitz Platz 2, Freising, Germany
| | - Anna Machlet
- Department of Ecology and Ecosystem Management-Chair for Ecophysiology of Plants, Technische Universität München, Hans-Carl-von-Carlowitz Platz 2, Freising, Germany
| | - Rainer Matyssek
- Department of Ecology and Ecosystem Management-Chair for Ecophysiology of Plants, Technische Universität München, Hans-Carl-von-Carlowitz Platz 2, Freising, Germany
| | - Karl-Heinz Häberle
- Department of Ecology and Ecosystem Management-Chair for Ecophysiology of Plants, Technische Universität München, Hans-Carl-von-Carlowitz Platz 2, Freising, Germany
| |
Collapse
|
37
|
Mencuccini M, Manzoni S, Christoffersen B. Modelling water fluxes in plants: from tissues to biosphere. New Phytol 2019; 222:1207-1222. [PMID: 30636295 DOI: 10.1111/nph.15681] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 12/18/2018] [Indexed: 05/02/2023]
Abstract
Contents Summary 1207 I. Introduction 1207 II. A brief history of modelling plant water fluxes 1208 III. Main components of plant water transport models 1208 IV. Stand-scale water fluxes and coupling to climate and soil 1213 V. Water fluxes in terrestrial biosphere models and feedbacks to community dynamics 1215 VI. Outstanding challenges in modelling water fluxes in the soil-plant-atmosphere continuum 1217 Acknowledgements 1218 References 1218 SUMMARY: Models of plant water fluxes have evolved from studies focussed on understanding the detailed structure and functioning of specific components of the soil-plant-atmosphere (SPA) continuum to architectures often incorporated inside eco-hydrological and terrestrial biosphere (TB) model schemes. We review here the historical evolution of this field, examine the basic structure of a simplified individual-based model of plant water transport, highlight selected applications for specific ecological problems and conclude by examining outstanding issues requiring further improvements in modelling vegetation water fluxes. We particularly emphasise issues related to the scaling from tissue-level traits to individual-based predictions of water transport, the representation of nonlinear and hysteretic behaviour in soil-xylem hydraulics and the need to incorporate knowledge of hydraulics within broader frameworks of plant ecological strategies and their consequences for predicting community demography and dynamics.
Collapse
Affiliation(s)
| | - Stefano Manzoni
- Stockholm University, Stockholm, 10691, Sweden
- Bolin Centre for Climate Research, Stockholm University, SE-10691, Stockholm, Sweden
| | | |
Collapse
|
38
|
Savage JA. A temporal shift in resource allocation facilitates flowering before leaf out and spring vessel maturation in precocious species. Am J Bot 2019; 106:113-122. [PMID: 30629737 DOI: 10.1002/ajb2.1222] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 10/29/2018] [Indexed: 05/29/2023]
Abstract
PREMISE OF THE STUDY New growth in the spring requires resource mobilization in the vascular system at a time when xylem and phloem function are often reduced in seasonally cold climates. As a result, the timing of leaf out and/or flowering could depend on when the vascular system resumes normal function in the spring. This study investigated whether flowering time is influenced by vascular phenology in plants that flower precociously before they have leaves. METHODS Flower, leaf, and vascular phenology were monitored in pairs of precocious and non-precocious congeners. Differences in resource allocation were quantified by measuring bud dry mass and water content throughout the year, floral hydration was modelled, and a girdling treatment completed on branches in the field. KEY RESULTS Precocious flowering species invested more in floral buds the year before flowering than did their non-precocious congeners, thus mobilizing less water in the spring, which allowed flowering before new vessel maturation. CONCLUSIONS A shift in the timing of resource allocation in precocious flowering plants allowed them to flower before the production of mature vessels and minimized the significance of seasonal changes in vascular function to their flowering phenology. The low investment required to complete floral development in the spring when the plant vascular system is often compromised could explain why flowers can emerge before leaf out.
Collapse
Affiliation(s)
- Jessica A Savage
- Department of Biology, University of Minnesota, Duluth, MN, USA
- Arnold Arboretum, Harvard University, Boston, MA, USA
| |
Collapse
|
39
|
Mrad A, Domec JC, Huang CW, Lens F, Katul G. A network model links wood anatomy to xylem tissue hydraulic behaviour and vulnerability to cavitation. Plant Cell Environ 2018; 41:2718-2730. [PMID: 30071137 DOI: 10.1111/pce.13415] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 07/13/2018] [Accepted: 07/25/2018] [Indexed: 05/06/2023]
Abstract
Plant xylem response to drought is routinely represented by a vulnerability curve (VC). Despite the significance of VCs, the connection between anatomy and tissue-level hydraulic response to drought remains a subject of inquiry. We present a numerical model of water flow in flowering plant xylem that combines current knowledge on diffuse-porous anatomy and embolism spread to explore this connection. The model produces xylem networks and uses different parameterizations of intervessel connection vulnerability to embolism spread: the Young-Laplace equation and pit membrane stretching. Its purpose is upscaling processes occurring on the microscopic length scales, such as embolism propagation through pit membranes, to obtain tissue-scale hydraulics. The terminal branch VC of Acer glabrum was successfully reproduced relying only on real observations of xylem tissue anatomy. A sensitivity analysis shows that hydraulic performance and VC shape and location along the water tension axis are heavily dependent on anatomy. The main result is that the linkage between pit-scale and vessel-scale anatomical characters, along with xylem network topology, affects VCs significantly. This work underscores the importance of stepping up research related to the three-dimensional network structure of xylem tissues. The proposed model's versatility makes it an important tool to explore similar future questions.
Collapse
Affiliation(s)
- Assaad Mrad
- Nicholas School of the Environment, Duke University, Durham, NC, 27708, USA
| | - Jean-Christophe Domec
- Nicholas School of the Environment, Duke University, Durham, NC, 27708, USA
- Bordeaux Sciences Agro, UMR 1391 INRA-ISPA, 33175, Gradignan Cedex, France
| | - Cheng-Wei Huang
- Department of Biology, University of New Mexico, Albuquerque, NM, 87131-0001
| | - Frederic Lens
- Naturalis Biodiversity Center, Leiden University, P.O. Box 9517, 2300 RA Leiden, The Netherlands
| | - Gabriel Katul
- Nicholas School of the Environment, Duke University, Durham, NC, 27708, USA
| |
Collapse
|
40
|
Creek D, Blackman CJ, Brodribb TJ, Choat B, Tissue DT. Coordination between leaf, stem, and root hydraulics and gas exchange in three arid-zone angiosperms during severe drought and recovery. Plant Cell Environ 2018; 41:2869-2881. [PMID: 30106477 DOI: 10.1111/pce.13418] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Accepted: 07/30/2018] [Indexed: 05/13/2023]
Abstract
The ability to resist hydraulic dysfunction in leaves, stems, and roots strongly influences whether plants survive and recover from drought. However, the coordination of hydraulic function among different organs within species and their links to gas exchange during drought and recovery remains understudied. Here, we examine the interaction between gas exchange and hydraulic function in the leaves, stems, and roots of three semiarid evergreen species exposed to a cycle of severe water stress (associated with substantial cavitation) and recovery. In all species, stomatal closure occurred at water potentials well before 50% loss of stem hydraulic conductance, while in two species, leaves and/or roots were more vulnerable than stems. Following soil rewetting, leaf-level photosynthesis (Anet ) returned to prestress levels within 2-4 weeks, whereas stomatal conductance and canopy transpiration were slower to recover. The recovery of Anet was decoupled from the recovery of leaf, stem, and root hydraulics, which remained impaired throughout the recovery period. Our results suggest that in addition to high embolism resistance, early stomatal closure and hydraulic vulnerability segmentation confers drought tolerance in these arid zone species. The lack of substantial embolism refilling within all major organs suggests that vulnerability of the vascular system to drought-induced dysfunction is a defining trait for predicting postdrought recovery.
Collapse
Affiliation(s)
- Danielle Creek
- Hawkesbury Institute for the Environment, University of Western Sydney, Penrith, New South Wales, Australia
| | - Chris J Blackman
- Hawkesbury Institute for the Environment, University of Western Sydney, Penrith, New South Wales, Australia
| | - Timothy J Brodribb
- School of Biological Science, University of Tasmania, Hobart, Tasmania, Australia
| | - Brendan Choat
- Hawkesbury Institute for the Environment, University of Western Sydney, Penrith, New South Wales, Australia
| | - David T Tissue
- Hawkesbury Institute for the Environment, University of Western Sydney, Penrith, New South Wales, Australia
| |
Collapse
|
41
|
Zhang FP, Carins Murphy MR, Cardoso AA, Jordan GJ, Brodribb TJ. Similar geometric rules govern the distribution of veins and stomata in petals, sepals and leaves. New Phytol 2018; 219:1224-1234. [PMID: 29761509 DOI: 10.1111/nph.15210] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 04/09/2018] [Indexed: 05/27/2023]
Abstract
Investment in leaf veins (supplying xylem water) is balanced by stomatal abundance, such that sufficient water transport is provided for stomata to remain open when soil water is abundant. This coordination is mediated by a common dependence of vein and stomatal densities on cell size. Flowers may not conform to this same developmental pattern if they depend on water supplied by the phloem or have high rates of nonstomatal transpiration. We examined the relationships between veins, stomata and epidermal cells in leaves, sepals and petals of 27 angiosperms to determine whether common spacing rules applied to all tissues. Regression analysis found no evidence for different relationships within organ types. Both vein and stomatal densities were strongly associated with epidermal cell size within organs, but, for a given epidermal cell size, petals had fewer veins and stomata than sepals, which had fewer than leaves. Although our data support the concept of common scaling between veins and stomata in leaves and flowers, the large diversity in petal vein density suggests that, in some species, petal veins may be engaged in additional functions, such as the supply of water for high cuticular transpiration or for phloem delivery of water or carbohydrates.
Collapse
Affiliation(s)
- Feng-Ping Zhang
- Key Laboratory of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China
- School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, Tasmania, 7001, Australia
| | - Madeline R Carins Murphy
- School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, Tasmania, 7001, Australia
| | - Amanda A Cardoso
- School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, Tasmania, 7001, Australia
- Departamento de Biologia Vegetal, Universidade Federal Viçosa, Viçosa, Minas Gerais, 36570-000, Brazil
- Purdue Center for Plant Biology, Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA
| | - Gregory J Jordan
- School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, Tasmania, 7001, Australia
| | - Timothy J Brodribb
- School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, Tasmania, 7001, Australia
| |
Collapse
|
42
|
Cui H, Sivakumar B, Singh VP. Entropy Applications in Environmental and Water Engineering. Entropy (Basel) 2018; 20:e20080598. [PMID: 33265687 PMCID: PMC7513122 DOI: 10.3390/e20080598] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 08/09/2018] [Indexed: 01/15/2023]
Affiliation(s)
- Huijuan Cui
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
- Correspondence:
| | - Bellie Sivakumar
- UNSW Water Research Centre, School of Civil and Environmental Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
- Department of Civil Engineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra 400076, India
- State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China
| | - Vijay P. Singh
- Department of Biological and Agricultural Engineering & Zachry Department of Civil Engineering, Texas A and M University, College Station, TX 77843-2117, USA
| |
Collapse
|
43
|
Earles JM, Stevens JT, Sperling O, Orozco J, North MP, Zwieniecki MA. Extreme mid-winter drought weakens tree hydraulic-carbohydrate systems and slows growth. New Phytol 2018; 219:89-97. [PMID: 29663406 DOI: 10.1111/nph.15136] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 02/28/2018] [Indexed: 06/08/2023]
Abstract
Rising temperatures and extended periods of drought compromise tree hydraulic and carbohydrate systems, threatening forest health globally. Despite winter's biological significance to many forests, the effects of warmer and dryer winters on tree hydraulic and carbohydrate status have largely been overlooked. Here we report a sharp and previously unknown decline in stem water content of three conifer species during California's anomalous 2015 mid-winter drought that was followed by dampened spring starch accumulation. Recent precipitation and seasonal vapor pressure deficit (VPD) anomaly, not absolute VPD, best predicted the hydraulic patterns observed. By linking relative water content and hydraulic conductivity (Kh ), we estimated that stand-level Kh declined by 52% during California's 2015 mid-winter drought, followed by a 50% reduction in spring starch accumulation. Further examination of tree increment records indicated a concurrent decline of growth with rising mid-winter, but not summer, VPD anomaly. Thus, our findings suggest a seasonality to tree hydraulic and carbohydrate declines, with consequences for annual growth rates, raising novel physiological and ecological questions about how rising winter temperatures will affect forest vitality as climate changes.
Collapse
Affiliation(s)
- J Mason Earles
- School of Forestry & Environmental Studies, Yale University, New Haven, CT, 06511, USA
| | - Jens T Stevens
- Department of Environmental Science, Policy and Management, University of California Berkeley, 145 Mulford Hall, Berkeley, CA, 94720, USA
| | - Or Sperling
- Volcani Center, Agricultural Research Organization, M.P. Negev, 85280, Israel
| | - Jessica Orozco
- Department of Plant Sciences, University of California Davis, One Shields Ave, Davis, CA, 95616, USA
| | - Malcolm P North
- Department of Plant Sciences, University of California Davis, One Shields Ave, Davis, CA, 95616, USA
- USDA Forest Service, PSW Research Station, 1731 Research Park Dr., Davis, CA, 95618, USA
| | - Maciej A Zwieniecki
- Department of Plant Sciences, University of California Davis, One Shields Ave, Davis, CA, 95616, USA
| |
Collapse
|
44
|
de Pee C. Circulation and flow: Immanent metaphors in the financial debates of Northern Song China (960-1127 CE). Hist Sci 2018; 56:168-195. [PMID: 29900759 DOI: 10.1177/0073275317724706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The Song Empire (960-1279 CE) had a larger population, a higher agricultural output, a more efficient infrastructure, and a more extensive monetary system than any previous empire in Chinese history. As local jurisdictions during the eleventh century became entangled in empire-wide economic relations and trans-regional commercial litigation, imperial officials sought to reduce the bewildering movement of people, goods, and money to an immanent cosmic pattern. They reasoned that because money and commerce brought to imperial subjects the goods they required to survive, money and commerce must be beneficent, and because they were beneficent, they must conform to the immanent pattern of the moral cosmos, as did everything else that was enduringly sustaining of life and wellbeing. And because money and commerce conformed to the moral cosmos, officials attempted to understand their workings by analogy with other phenomena that sustained human life, such as the flow of water and the circulation of vital essences through the human body. During the 1030s and 1040s, officials and scholars believed that knowledge of the cosmic pattern lay within their grasp, and that this knowledge would allow them to align culture with nature, and the present with hallowed antiquity. By the 1080s, however, this intellectual optimism had been defeated by irreconcilable disagreements about financial and economic policy. The failure of the attempt to understand finance by natural analogy draws attention to the underlying ideological insistence on moral learning as the basis for political power, and to the very limited range of economic discourse that has been preserved in eleventh-century texts.
Collapse
|
45
|
Speck O, Schlechtendahl M, Borm F, Kampowski T, Speck T. Humidity-dependent wound sealing in succulent leaves of Delosperma cooperi - An adaptation to seasonal drought stress. Beilstein J Nanotechnol 2018; 9:175-186. [PMID: 29441263 PMCID: PMC5789399 DOI: 10.3762/bjnano.9.20] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 12/19/2017] [Indexed: 05/24/2023]
Abstract
During evolution, plants evolved various reactions to wounding. Fast wound sealing and subsequent healing represent a selective advantage of particular importance for plants growing in arid habitats. An effective self-sealing function by internal deformation has been found in the succulent leaves of Delosperma cooperi. After a transversal incision, the entire leaf bends until the wound is closed. Our results indicate that the underlying sealing principle is a combination of hydraulic shrinking and swelling as the main driving forces and growth-induced mechanical pre-stresses in the tissues. Hydraulic effects were measured in terms of the relative bending angle over 55 minutes under various humidity conditions. The higher the relative air humidity, the lower the bending angle. Negative bending angles were found when a droplet of liquid water was applied to the wound. The statistical analysis revealed highly significant differences of the single main effects such as "humidity conditions in the wound region" and "time after wounding" and their interaction effect. The centripetal arrangement of five tissue layers with various thicknesses and significantly different mechanical properties might play an additional role with regard to mechanically driven effects. Injury disturbs the mechanical equilibrium, with pre-stresses leading to internal deformation until a new equilibrium is reached. In the context of self-sealing by internal deformation, the highly flexible wide-band tracheids, which form a net of vascular bundles, are regarded as paedomorphic tracheids, which are specialised to prevent cell collapse under drought stress and allow for building growth-induced mechanical pre-stresses.
Collapse
Affiliation(s)
- Olga Speck
- Plant Biomechanics Group, Botanic Garden, Faculty of Biology, University of Freiburg, Schänzlestraße 1, 79104 Freiburg, Germany
- Competence Network Biomimetics, Baden-Württemberg, Schänzlestraße 1, 79104 Freiburg, Germany
- Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT), University of Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
| | - Mark Schlechtendahl
- Plant Biomechanics Group, Botanic Garden, Faculty of Biology, University of Freiburg, Schänzlestraße 1, 79104 Freiburg, Germany
- Freiburg Materials Research Center (FMF), University of Freiburg, Stefan-Meier-Str. 21, 79104 Freiburg, Germany
| | - Florian Borm
- Plant Biomechanics Group, Botanic Garden, Faculty of Biology, University of Freiburg, Schänzlestraße 1, 79104 Freiburg, Germany
| | - Tim Kampowski
- Plant Biomechanics Group, Botanic Garden, Faculty of Biology, University of Freiburg, Schänzlestraße 1, 79104 Freiburg, Germany
- Freiburg Materials Research Center (FMF), University of Freiburg, Stefan-Meier-Str. 21, 79104 Freiburg, Germany
| | - Thomas Speck
- Plant Biomechanics Group, Botanic Garden, Faculty of Biology, University of Freiburg, Schänzlestraße 1, 79104 Freiburg, Germany
- Competence Network Biomimetics, Baden-Württemberg, Schänzlestraße 1, 79104 Freiburg, Germany
- Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT), University of Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
- Freiburg Materials Research Center (FMF), University of Freiburg, Stefan-Meier-Str. 21, 79104 Freiburg, Germany
| |
Collapse
|
46
|
|
47
|
Azuma W, Nakashima S, Yamakita E, Ishii HR, Kuroda K. Water retained in tall Cryptomeria japonica leaves as studied by infrared micro-spectroscopy. Tree Physiol 2017; 37:1367-1378. [PMID: 28985389 DOI: 10.1093/treephys/tpx085] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Accepted: 06/08/2017] [Indexed: 06/07/2023]
Abstract
Recent studies in the tallest tree species suggest that physiological and anatomical traits of tree-top leaves are adapted to water-limited conditions. In order to examine water retention mechanism of leaves in a tall tree, infrared (IR) micro-spectroscopy was conducted on mature leaf cross-sections of tall Cryptomeria japonica D. Don from four different heights (51, 43, 31 and 19 m). We measured IR transmission spectra and mainly analyzed OH (3700-3000 cm-1) and C-O (1190-845 cm-1) absorption bands, indicating water molecules and sugar groups, respectively. The changes in IR spectra of leaf sections from different heights were compared with bulk-leaf hydraulics. Both average OH band area of the leaf sections and leaf water content were larger in the upper-crown, while osmotic potential at saturation did not vary with height, suggesting higher dissolved sugar contents of upper-crown leaves. As cell-wall is the main cellular structure of leaves, we inferred that larger average C-O band area of upper-crown leaves reflected higher content of structural polysaccharides such as cellulose, hemicellulose and pectin. Infrared micro-spectroscopic imaging showed that the OH and C-O band areas are large in the vascular bundle, transfusion tissue and epidermis. Infrared spectra of individual tissue showed that much more water is retained in vascular bundle and transfusion tissue than mesophyll. These results demonstrate that IR micro-spectroscopy is a powerful tool for visualizing detailed, quantitative information on the spatial distribution of chemical substances within plant tissues, which cannot be done using conventional methods like histochemical staining. The OH band could be well reproduced by four Gaussian OH components around 3530 (free water: long H bond), 3410 (pectin-like OH species), 3310 (cellulose-like OH species) and 3210 (bound water: short H bond) cm-1, and all of these OH components were higher in the upper crown while their relative proportions did not vary with height. Based on the spectral analyses, we inferred that polysaccharides play a key role in biomolecular retention of water in leaves of tall C. japonica.
Collapse
Affiliation(s)
- Wakana Azuma
- Graduate School of Agricultural Science, Kobe University, Kobe 675-8501, Japan
- Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Satoru Nakashima
- Graduate School of Science, Osaka University, Osaka 560-0043, Japan
| | - Eri Yamakita
- Graduate School of Science, Osaka University, Osaka 560-0043, Japan
| | - H Roaki Ishii
- Graduate School of Agricultural Science, Kobe University, Kobe 675-8501, Japan
| | - Keiko Kuroda
- Graduate School of Agricultural Science, Kobe University, Kobe 675-8501, Japan
| |
Collapse
|
48
|
Grossiord C, Sevanto S, Borrego I, Chan AM, Collins AD, Dickman LT, Hudson PJ, McBranch N, Michaletz ST, Pockman WT, Ryan M, Vilagrosa A, McDowell NG. Tree water dynamics in a drying and warming world. Plant Cell Environ 2017; 40:1861-1873. [PMID: 28556263 DOI: 10.1111/pce.12991] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 05/02/2017] [Accepted: 05/09/2017] [Indexed: 05/16/2023]
Abstract
Disentangling the relative impacts of precipitation reduction and vapour pressure deficit (VPD) on plant water dynamics and determining whether acclimation may influence these patterns in the future is an important challenge. Here, we report sap flux density (FD ), stomatal conductance (Gs ), hydraulic conductivity (KL ) and xylem anatomy in piñon pine (Pinus edulis) and juniper (Juniperus monosperma) trees subjected to five years of precipitation reduction, atmospheric warming (elevated VPD) and their combined effects. No acclimation occurred under precipitation reduction: lower Gs and FD were found for both species compared to ambient conditions. Warming reduced the sensibility of stomata to VPD for both species but resulted in the maintenance of Gs and FD to ambient levels only for piñon. For juniper, reduced soil moisture under warming negated benefits of stomatal adjustments and resulted in reduced FD , Gs and KL . Although reduced stomatal sensitivity to VPD also occurred under combined stresses, reductions in Gs , FD and KL took place to similar levels as under single stresses for both species. Our results show that stomatal conductance adjustments to high VPD could minimize but not entirely prevent additive effects of warming and drying on water use and carbon acquisition of trees in semi-arid regions.
Collapse
Affiliation(s)
- Charlotte Grossiord
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Sanna Sevanto
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Isaac Borrego
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Allison M Chan
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Adam D Collins
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Lee T Dickman
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Patrick J Hudson
- Department of Biology, MSC03 202, University of New Mexico, Albuquerque, NM, 87131-0001, USA
| | - Natalie McBranch
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Sean T Michaletz
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - William T Pockman
- Department of Biology, MSC03 202, University of New Mexico, Albuquerque, NM, 87131-0001, USA
| | - Max Ryan
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Alberto Vilagrosa
- Fundación CEAM, Joint Research Unit University of Alicante - CEAM, Univ. Alicante, PO Box 99, 03080, Alicante, Spain
| | - Nate G McDowell
- Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| |
Collapse
|
49
|
Bourne AE, Creek D, Peters JMR, Ellsworth DS, Choat B. Species climate range influences hydraulic and stomatal traits in Eucalyptus species. Ann Bot 2017; 120:123-133. [PMID: 28369162 PMCID: PMC5737682 DOI: 10.1093/aob/mcx020] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 02/17/2017] [Indexed: 05/05/2023]
Abstract
BACKGROUND AND AIMS Plant hydraulic traits influence the capacity of species to grow and survive in water-limited environments, but their comparative study at a common site has been limited. The primary aim of this study was to determine whether selective pressures on species originating in drought-prone environments constrain hydraulic traits among related species grown under common conditions. METHODS Leaf tissue water relations, xylem anatomy, stomatal behaviour and vulnerability to drought-induced embolism were measured on six Eucalyptus species growing in a common garden to determine whether these traits were related to current species climate range and to understand linkages between the traits. KEY RESULTS Hydraulically weighted xylem vessel diameter, leaf turgor loss point, the water potential at stomatal closure and vulnerability to drought-induced embolism were significantly ( P < 0·05) correlated with climate parameters from the species range. There was a co-ordination between stem and leaf parameters with the water potential at turgor loss, 12 % loss of conductivity and the point of stomatal closure significantly correlated. CONCLUSIONS The correlation of hydraulic, stomatal and anatomical traits with climate variables from the species' original ranges suggests that these traits are genetically constrained. The conservative nature of xylem traits in Eucalyptus trees has important implications for the limits of species responses to changing environmental conditions and thus for species survival and distribution into the future, and yields new information for physiological models.
Collapse
Affiliation(s)
- Aimee E. Bourne
- Western Sydney University, Hawkesbury Institute for the Environment, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Danielle Creek
- Western Sydney University, Hawkesbury Institute for the Environment, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Jennifer M. R. Peters
- Western Sydney University, Hawkesbury Institute for the Environment, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - David S. Ellsworth
- Western Sydney University, Hawkesbury Institute for the Environment, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Brendan Choat
- Western Sydney University, Hawkesbury Institute for the Environment, Locked Bag 1797, Penrith, NSW 2751, Australia
- For correspondence. E-mail
| |
Collapse
|
50
|
Tardieu F, Parent B. Predictable 'meta-mechanisms' emerge from feedbacks between transpiration and plant growth and cannot be simply deduced from short-term mechanisms. Plant Cell Environ 2017; 40:846-857. [PMID: 27569520 DOI: 10.1111/pce.12822] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 08/23/2016] [Accepted: 08/24/2016] [Indexed: 05/19/2023]
Abstract
Growth under water deficit is controlled by short-term mechanisms but, because of numerous feedbacks, the combination of these mechanisms over time often results in outputs that cannot be deduced from the simple inspection of individual mechanisms. It can be analysed with dynamic models in which causal relationships between variables are considered at each time-step, allowing calculation of outputs that are routed back to inputs for the next time-step and that can change the system itself. We first review physiological mechanisms involved in seven feedbacks of transpiration on plant growth, involving changes in tissue hydraulic conductance, stomatal conductance, plant architecture and underlying factors such as hormones or aquaporins. The combination of these mechanisms over time can result in non-straightforward conclusions as shown by examples of simulation outputs: 'over production of abscisic acid (ABA) can cause a lower concentration of ABA in the xylem sap ', 'decreasing root hydraulic conductance when evaporative demand is maximum can improve plant performance' and 'rapid root growth can decrease yield'. Systems of equations simulating feedbacks over numerous time-steps result in logical and reproducible emergent properties that can be viewed as 'meta-mechanisms' at plant level, which have similar roles as mechanisms at cell level.
Collapse
Affiliation(s)
- François Tardieu
- INRA, UMR759 Laboratoire d'Ecophysiologie des Plantes sous Stress Environnementaux, Montpellier, F-34060, France
| | - Boris Parent
- INRA, UMR759 Laboratoire d'Ecophysiologie des Plantes sous Stress Environnementaux, Montpellier, F-34060, France
| |
Collapse
|