1
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Diao H, Cernusak LA, Saurer M, Gessler A, Siegwolf RTW, Lehmann MM. Uncoupling of stomatal conductance and photosynthesis at high temperatures: mechanistic insights from online stable isotope techniques. THE NEW PHYTOLOGIST 2024; 241:2366-2378. [PMID: 38303410 DOI: 10.1111/nph.19558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 01/12/2024] [Indexed: 02/03/2024]
Abstract
The strong covariation of temperature and vapour pressure deficit (VPD) in nature limits our understanding of the direct effects of temperature on leaf gas exchange. Stable isotopes in CO2 and H2 O vapour provide mechanistic insight into physiological and biochemical processes during leaf gas exchange. We conducted combined leaf gas exchange and online isotope discrimination measurements on four common European tree species across a leaf temperature range of 5-40°C, while maintaining a constant leaf-to-air VPD (0.8 kPa) without soil water limitation. Above the optimum temperature for photosynthesis (30°C) under the controlled environmental conditions, stomatal conductance (gs ) and net photosynthesis rate (An ) decoupled across all tested species, with gs increasing but An decreasing. During this decoupling, mesophyll conductance (cell wall, plasma membrane and chloroplast membrane conductance) consistently and significantly decreased among species; however, this reduction did not lead to reductions in CO2 concentration at the chloroplast surface and stroma. We question the conventional understanding that diffusional limitations of CO2 contribute to the reduction in photosynthesis at high temperatures. We suggest that stomata and mesophyll membranes could work strategically to facilitate transpiration cooling and CO2 supply, thus alleviating heat stress on leaf photosynthetic function, albeit at the cost of reduced water-use efficiency.
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Affiliation(s)
- Haoyu Diao
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, 8903, Switzerland
| | - Lucas A Cernusak
- College of Science and Engineering, James Cook University, Cairns, Qld, 4879, Australia
| | - Matthias Saurer
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, 8903, Switzerland
| | - Arthur Gessler
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, 8903, Switzerland
- Institute of Terrestrial Ecosystems, ETH Zurich, Zurich, 8092, Switzerland
| | - Rolf T W Siegwolf
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, 8903, Switzerland
| | - Marco M Lehmann
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, 8903, Switzerland
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2
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Walker BJ, Driever SM, Kromdijk J, Lawson T, Busch FA. Tools for Measuring Photosynthesis at Different Scales. Methods Mol Biol 2024; 2790:1-26. [PMID: 38649563 DOI: 10.1007/978-1-0716-3790-6_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
Measurements of in vivo photosynthesis are powerful tools that probe the largest fluxes of carbon and energy in an illuminated leaf, but often the specific techniques used are so varied and specialized that it is difficult for researchers outside the field to select and perform the most useful assays for their research questions. The goal of this chapter is to provide a broad overview of the current tools available for the study of photosynthesis, both in vivo and in vitro, so as to provide a foundation for selecting appropriate techniques, many of which are presented in detail in subsequent chapters. This chapter will also organize current methods into a comparative framework and provide examples of how they have been applied to research questions of broad agronomical, ecological, or biological importance. This chapter closes with an argument that the future of in vivo measurements of photosynthesis lies in the ability to use multiple methods simultaneously and discusses the benefits of this approach to currently open physiological questions. This chapter, combined with the relevant methods chapters, could serve as a laboratory course in methods in photosynthesis research or as part of a more comprehensive laboratory course in general plant physiology methods.
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Affiliation(s)
- Berkley J Walker
- Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
- Department of Plant Biology, Michigan State University, East Lansing, MI, USA
| | - Steven M Driever
- Centre for Crop Systems Analysis, Wageningen University and Research, Wageningen, The Netherlands
| | - Johannes Kromdijk
- Department of Plant Sciences, University of Cambridge, Cambridge, UK
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana, IL, USA
| | - Tracy Lawson
- School of Life Sciences, University of Essex, Colchester, UK
| | - Florian A Busch
- School of Biosciences and The Birmingham Institute of Forest Research, University of Birmingham, Birmingham, UK.
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3
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Gilman IS, Smith JAC, Holtum JAM, Sage RF, Silvera K, Winter K, Edwards EJ. The CAM lineages of planet Earth. ANNALS OF BOTANY 2023; 132:627-654. [PMID: 37698538 PMCID: PMC10799995 DOI: 10.1093/aob/mcad135] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 01/09/2023] [Accepted: 09/11/2023] [Indexed: 09/13/2023]
Abstract
BACKGROUND AND SCOPE The growth of experimental studies of crassulacean acid metabolism (CAM) in diverse plant clades, coupled with recent advances in molecular systematics, presents an opportunity to re-assess the phylogenetic distribution and diversity of species capable of CAM. It has been more than two decades since the last comprehensive lists of CAM taxa were published, and an updated survey of the occurrence and distribution of CAM taxa is needed to facilitate and guide future CAM research. We aimed to survey the phylogenetic distribution of these taxa, their diverse morphology, physiology and ecology, and the likely number of evolutionary origins of CAM based on currently known lineages. RESULTS AND CONCLUSIONS We found direct evidence (in the form of experimental or field observations of gas exchange, day-night fluctuations in organic acids, carbon isotope ratios and enzymatic activity) for CAM in 370 genera of vascular plants, representing 38 families. Further assumptions about the frequency of CAM species in CAM clades and the distribution of CAM in the Cactaceae and Crassulaceae bring the currently estimated number of CAM-capable species to nearly 7 % of all vascular plants. The phylogenetic distribution of these taxa suggests a minimum of 66 independent origins of CAM in vascular plants, possibly with dozens more. To achieve further insight into CAM origins, there is a need for more extensive and systematic surveys of previously unstudied lineages, particularly in living material to identify low-level CAM activity, and for denser sampling to increase phylogenetic resolution in CAM-evolving clades. This should allow further progress in understanding the functional significance of this pathway by integration with studies on the evolution and genomics of CAM in its many forms.
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Affiliation(s)
- Ian S Gilman
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA
| | | | - Joseph A M Holtum
- College of Science and Engineering, James Cook University, Townsville, Queensland, Australia
| | - Rowan F Sage
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada
| | - Katia Silvera
- Smithsonian Tropical Research Institute, Balboa, Ancón, Panama
- Department of Botany & Plant Sciences, University of California, Riverside, CA, USA
| | - Klaus Winter
- Smithsonian Tropical Research Institute, Balboa, Ancón, Panama
| | - Erika J Edwards
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA
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4
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Xiong D. Leaf anatomy does not explain the large variability of mesophyll conductance across C 3 crop species. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 113:1035-1048. [PMID: 36602006 DOI: 10.1111/tpj.16098] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Revised: 12/29/2022] [Accepted: 01/02/2023] [Indexed: 06/17/2023]
Abstract
Increasing mesophyll conductance of CO2 (gm ) is a strategy to improve photosynthesis in C3 crops. However, the relative importance of different anatomical traits in determining gm in crops is unclear. Mesophyll conductance measurements were performed on 10 crops using the online carbon isotope discrimination method and the 'variable J' method in parallel. The influences of crucial leaf anatomical traits on gm were evaluated using a one-dimensional anatomical CO2 diffusion model. The gm values measured using two independent methods were compatible, although significant differences were observed in their absolute values. Quantitative analysis showed that cell wall thickness and chloroplast stroma thickness are the most important elements along the diffusion pathway. Unexpectedly, the large variability of gm across crops was not associated with any investigated leaf anatomical traits except chloroplast thickness. The gm values estimated using the anatomical model differed remarkably from the values measured in vivo in most species. However, when the species-specific effective porosity of the cell wall and the species-specific facilitation effect of CO2 diffusion across the membrane and chloroplast stoma were taken into account, the model could output gm values very similar to those measured in vivo. These results indicate that gm variation across crops is probably also driven by the effective porosity of the cell wall and effects of facilitation of CO2 transport across the membrane and chloroplast stroma in addition to the thicknesses of the elements.
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Affiliation(s)
- Dongliang Xiong
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
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5
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Li TX, Shen-Tu XL, Xu L, Zhang WJ, Duan JP, Song YB, Dong M. Intraspecific and sex-dependent variation of leaf traits along altitude gradient in the endangered dioecious tree Taxus fuana Nan Li & R.R. Mill. FRONTIERS IN PLANT SCIENCE 2022; 13:996750. [PMID: 36325570 PMCID: PMC9618961 DOI: 10.3389/fpls.2022.996750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 09/09/2022] [Indexed: 06/16/2023]
Abstract
Plant intraspecific trait variation (ITV) including sex-dependent differences are matters of many ecological consequences, from individual to ecosystem, especially in endangered and rare species. Taxus fuana is an endangered dioecious species with small and isolated populations endemic to the Himalayas region. Little is known about its trait variation between sexes, and among populations. In this study, 18 leaf traits from 179 reproductive trees (males and females) along the altitude (2600-3200m a.s.l.) of the T. fuana populations distributed in Gyirong County, Tibet, China, were measured. ITV and sources of variation in leaf traits were assessed. The relationship between leaf traits of males and females and altitude was analyzed separately. Variations in leaf traits of T. fuana ranged from 3.1% to 24.2%, with the smallest in leaf carbon content and the largest in leaf thickness to area ratio. On average 78.13% of the variation in leaf traits was from within populations and 21.87% among populations. The trends in leaf width, leaf nitrogen to phosphorus ratio, leaf carbon to nitrogen ratio, leaf carbon isotope ratio, and leaf nitrogen isotope ratio in relation to altitude were the same for males and females. Leaf length to width ratio varied significantly with altitude only in males, while leaf phosphorus content, leaf nitrogen content, and leaf carbon to phosphorus ratio varied significantly with altitude only in females. The correlation coefficients of most leaf traits of females with altitude were larger than that of males. In the relationship between leaf traits, there was a high similarity among males and females, but the altitude accounted for more explanation in females than in males. Our results suggested that the variation in leaf traits of T. fuana was small and did not dominate the interspecific competition in the local communities. Adaptation to the altitude gradient of T. fuana might be through altering nutrient storage processes and water use efficiency. Adaptation of male and female T. fuana to environmental changes showed differences, where the males were more tolerant and the females responded greatly to altitude. The differences in adaptation strategies between male and female T. fuana may be detrimental to the maintenance of their populations.
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Affiliation(s)
| | | | | | | | | | | | - Ming Dong
- *Correspondence: Yao-Bin Song, ; Ming Dong,
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6
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Fradera-Soler M, Grace OM, Jørgensen B, Mravec J. Elastic and collapsible: current understanding of cell walls in succulent plants. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:2290-2307. [PMID: 35167681 PMCID: PMC9015807 DOI: 10.1093/jxb/erac054] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 02/11/2022] [Indexed: 05/11/2023]
Abstract
Succulent plants represent a large functional group of drought-resistant plants that store water in specialized tissues. Several co-adaptive traits accompany this water-storage capacity to constitute the succulent syndrome. A widely reported anatomical adaptation of cell walls in succulent tissues allows them to fold in a regular fashion during extended drought, thus preventing irreversible damage and permitting reversible volume changes. Although ongoing research on crop and model species continuously reports the importance of cell walls and their dynamics in drought resistance, the cell walls of succulent plants have received relatively little attention to date, despite the potential of succulents as natural capital to mitigate the effects of climate change. In this review, we summarize current knowledge of cell walls in drought-avoiding succulents and their effects on tissue biomechanics, water relations, and photosynthesis. We also highlight the existing knowledge gaps and propose a hypothetical model for regulated cell wall folding in succulent tissues upon dehydration. Future perspectives of methodological development in succulent cell wall characterization, including the latest technological advances in molecular and imaging techniques, are also presented.
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Affiliation(s)
- Marc Fradera-Soler
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg, Denmark
- Royal Botanic Gardens, Kew, Richmond, Surrey, UK
- Correspondence: or
| | | | | | - Jozef Mravec
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg, Denmark
- Correspondence: or
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7
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Zhang D, Du Q, Sun P, Lou J, Li X, Li Q, Wei M. Physiological and Transcriptomic Analyses Revealed the Implications of Abscisic Acid in Mediating the Rate-Limiting Step for Photosynthetic Carbon Dioxide Utilisation in Response to Vapour Pressure Deficit in Solanum Lycopersicum (Tomato). FRONTIERS IN PLANT SCIENCE 2021; 12:745110. [PMID: 34858453 PMCID: PMC8631768 DOI: 10.3389/fpls.2021.745110] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 09/24/2021] [Indexed: 06/13/2023]
Abstract
The atmospheric vapour pressure deficit (VPD) has been demonstrated to be a significant environmental factor inducing plant water stress and affecting plant photosynthetic productivity. Despite this, the rate-limiting step for photosynthesis under varying VPD is still unclear. In the present study, tomato plants were cultivated under two contrasting VPD levels: high VPD (3-5 kPa) and low VPD (0.5-1.5 kPa). The effect of long-term acclimation on the short-term rapid VPD response was examined across VPD ranging from 0.5 to 4.5 kPa. Quantitative photosynthetic limitation analysis across the VPD range was performed by combining gas exchange and chlorophyll fluorescence. The potential role of abscisic acid (ABA) in mediating photosynthetic carbon dioxide (CO2) uptake across a series of VPD was evaluated by physiological and transcriptomic analyses. The rate-limiting step for photosynthetic CO2 utilisation varied with VPD elevation in tomato plants. Under low VPD conditions, stomatal and mesophyll conductance was sufficiently high for CO2 transport. With VPD elevation, plant water stress was gradually pronounced and triggered rapid ABA biosynthesis. The contribution of stomatal and mesophyll limitation to photosynthesis gradually increased with an increase in the VPD. Consequently, the low CO2 availability inside chloroplasts substantially constrained photosynthesis under high VPD conditions. The foliar ABA content was negatively correlated with stomatal and mesophyll conductance for CO2 diffusion. Transcriptomic and physiological analyses revealed that ABA was potentially involved in mediating water transport and photosynthetic CO2 uptake in response to VPD variation. The present study provided new insights into the underlying mechanism of photosynthetic depression under high VPD stress.
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Affiliation(s)
- Dalong Zhang
- College of Horticultural Science and Engineering, Shandong Agricultural University, Tai'an, China
- State Key Laboratory of Crop Biology, Tai'an, China
- Scientific Observing and Experimental Station of Environment Controlled Agricultural Engineering in Huang-Huai-Hai Region, Ministry of Agriculture, Beijing, China
| | - Qingjie Du
- College of Horticulture, Henan Agricultural University, Zhengzhou, China
| | - Po Sun
- College of Horticultural Science and Engineering, Shandong Agricultural University, Tai'an, China
| | - Jie Lou
- College of Horticultural Science and Engineering, Shandong Agricultural University, Tai'an, China
| | - Xiaotian Li
- College of Horticultural Science and Engineering, Shandong Agricultural University, Tai'an, China
| | - Qingming Li
- College of Horticultural Science and Engineering, Shandong Agricultural University, Tai'an, China
- State Key Laboratory of Crop Biology, Tai'an, China
- Scientific Observing and Experimental Station of Environment Controlled Agricultural Engineering in Huang-Huai-Hai Region, Ministry of Agriculture, Beijing, China
| | - Min Wei
- College of Horticultural Science and Engineering, Shandong Agricultural University, Tai'an, China
- State Key Laboratory of Crop Biology, Tai'an, China
- Scientific Observing and Experimental Station of Environment Controlled Agricultural Engineering in Huang-Huai-Hai Region, Ministry of Agriculture, Beijing, China
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8
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Harwood R, Théroux-Rancourt G, Barbour MM. Understanding airspace in leaves: 3D anatomy and directional tortuosity. PLANT, CELL & ENVIRONMENT 2021; 44:2455-2465. [PMID: 33974719 DOI: 10.1111/pce.14079] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 04/24/2021] [Indexed: 05/24/2023]
Abstract
The leaf intercellular airspace is a tortuous environment consisting of cells of different shapes, packing densities, and orientation, all of which have an effect on the travelling distance of molecules from the stomata to the mesophyll cell surfaces. Tortuosity, the increase in displacement over the actual distance between two points, is typically defined as encompassing the whole leaf airspace, but heterogeneity in pore dimensions and orientation between the spongy and palisade mesophyll likely result in heterogeneity in tortuosity along different axes and would predict longer traveling distance along the path of least tortuosity, such as vertically within the columnar cell matrix of the palisade layer. Here, we compare a previously established geometric method to a random walk approach, novel for this analysis in plant leaves, in four different Eucalyptus species. The random walk method allowed us to quantify directional tortuosity across the whole leaf profile, and separately for the spongy and palisade mesophyll. For all species tortuosity was higher in the palisade mesophyll than the spongy mesophyll and horizontal (parallel to the epidermis) tortuosity was consistently higher than vertical (from epidermis to epidermis) tortuosity. We demonstrate that a random walk approach improves on previous geometric approaches and is valuable for investigating CO2 and H2 O transport within leaves.
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Affiliation(s)
- Richard Harwood
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, Australia
| | | | - Margaret M Barbour
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, Australia
- School of Science, The University of Waikato, Hamilton, New Zealand
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9
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Pathare VS, Sonawane BV, Koteyeva N, Cousins AB. C 4 grasses adapted to low precipitation habitats show traits related to greater mesophyll conductance and lower leaf hydraulic conductance. PLANT, CELL & ENVIRONMENT 2020; 43:1897-1910. [PMID: 32449181 DOI: 10.1111/pce.13807] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 05/18/2020] [Indexed: 06/11/2023]
Abstract
In habitats with low water availability, a fundamental challenge for plants will be to maximize photosynthetic C-gain while minimizing transpirational water-loss. This trade-off between C-gain and water-loss can in part be achieved through the coordination of leaf-level photosynthetic and hydraulic traits. To test the relationship of photosynthetic C-gain and transpirational water-loss, we grew, under common growth conditions, 18 C4 grasses adapted to habitats with different mean annual precipitation (MAP) and measured leaf-level structural and anatomical traits associated with mesophyll conductance (gm ) and leaf hydraulic conductance (Kleaf ). The C4 grasses adapted to lower MAP showed greater mesophyll surface area exposed to intercellular air spaces (Smes ) and adaxial stomatal density (SDada ) which supported greater gm . These grasses also showed greater leaf thickness and vein-to-epidermis distance, which may lead to lower Kleaf . Additionally, grasses with greater gm and lower Kleaf also showed greater photosynthetic rates (Anet ) and leaf-level water-use efficiency (WUE). In summary, we identify a suite of leaf-level traits that appear important for adaptation of C4 grasses to habitats with low MAP and may be useful to identify C4 species showing greater Anet and WUE in drier conditions.
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Affiliation(s)
- Varsha S Pathare
- School of Biological Sciences, Washington State University, Pullman, Washington, USA
| | - Balasaheb V Sonawane
- School of Biological Sciences, Washington State University, Pullman, Washington, USA
| | - Nouria Koteyeva
- School of Biological Sciences, Washington State University, Pullman, Washington, USA
- Laboratory of Anatomy and Morphology, V.L. Komarov Botanical Institute of the Russian Academy of Sciences, St. Petersburg, Russia
| | - Asaph B Cousins
- School of Biological Sciences, Washington State University, Pullman, Washington, USA
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10
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Yin X, van der Putten PEL, Belay D, Struik PC. Using photorespiratory oxygen response to analyse leaf mesophyll resistance. PHOTOSYNTHESIS RESEARCH 2020; 144:85-99. [PMID: 32040701 PMCID: PMC7113236 DOI: 10.1007/s11120-020-00716-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 01/27/2020] [Indexed: 05/12/2023]
Abstract
Classical approaches to estimate mesophyll conductance ignore differences in resistance components for CO2 from intercellular air spaces (IAS) and CO2 from photorespiration (F) and respiration (Rd). Consequently, mesophyll conductance apparently becomes sensitive to (photo)respiration relative to net photosynthesis, (F + Rd)/A. This sensitivity depends on several hard-to-measure anatomical properties of mesophyll cells. We developed a method to estimate the parameter m (0 ≤ m ≤ 1) that lumps these anatomical properties, using gas exchange and chlorophyll fluorescence measurements where (F + Rd)/A ratios vary. This method was applied to tomato and rice leaves measured at five O2 levels. The estimated m was 0.3 for tomato but 0.0 for rice, suggesting that classical approaches implying m = 0 work well for rice. The mesophyll conductance taking the m factor into account still responded to irradiance, CO2, and O2 levels, similar to response patterns of stomatal conductance to these variables. Largely due to different m values, the fraction of (photo)respired CO2 being refixed within mesophyll cells was lower in tomato than in rice. But that was compensated for by the higher fraction via IAS, making the total re-fixation similar for both species. These results, agreeing with CO2 compensation point estimates, support our method of effectively analysing mesophyll resistance.
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Affiliation(s)
- Xinyou Yin
- Centre for Crop Systems Analysis, Wageningen University & Research, P.O. Box 430, 6700 AK, Wageningen, The Netherlands.
| | - Peter E L van der Putten
- Centre for Crop Systems Analysis, Wageningen University & Research, P.O. Box 430, 6700 AK, Wageningen, The Netherlands
| | - Daniel Belay
- Selale University, P.O. Box 245, Fiche, Ethiopia
| | - Paul C Struik
- Centre for Crop Systems Analysis, Wageningen University & Research, P.O. Box 430, 6700 AK, Wageningen, The Netherlands
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11
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Xiong D, Nadal M. Linking water relations and hydraulics with photosynthesis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:800-815. [PMID: 31677190 DOI: 10.1111/tpj.14595] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 10/16/2019] [Accepted: 10/24/2019] [Indexed: 05/28/2023]
Abstract
For land plants, water is the principal governor of growth. Photosynthetic performance is highly dependent on the stable and suitable water status of leaves, which is balanced by the water transport capacity, the water loss rate as well as the water capacitance of the plant. This review discusses the links between leaf water status and photosynthesis, specifically focussing on the coordination of CO2 and water transport within leaves, and the potential role of leaf capacitance and elasticity on CO2 and water transport.
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Affiliation(s)
- Dongliang Xiong
- National Key Laboratory of Crop Genetic Improvement, MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Miquel Nadal
- Research Group on Plant Biology under Mediterranean Conditions, Departament de Biologia, Universitat de les Illes Balears (UIB) - Institute of Agro-Environmental Research and Water Economy (INAGEA), Carretera de Valldemossa, 07122, Palma, Spain
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12
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Ren T, Weraduwage SM, Sharkey TD. Prospects for enhancing leaf photosynthetic capacity by manipulating mesophyll cell morphology. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:1153-1165. [PMID: 30590670 DOI: 10.1093/jxb/ery448] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 12/25/2018] [Indexed: 06/09/2023]
Abstract
Leaves are beautifully specialized organs designed to maximize the use of light and CO2 for photosynthesis. Engineering leaf anatomy therefore holds great potential to enhance photosynthetic capacity. Here we review the effect of the dominant leaf anatomical traits on leaf photosynthesis and confirm that a high chloroplast surface area exposed to intercellular airspace per unit leaf area (Sc) is critical for efficient photosynthesis. The possibility of improving Sc through appropriately increasing mesophyll cell density is further analyzed. The potential influences of modifying mesophyll cell morphology on CO2 diffusion, light distribution within the leaf, and other physiological processes are also discussed. Some potential target genes regulating leaf mesophyll cell proliferation and expansion are explored. Indeed, more comprehensive research is needed to understand how manipulating mesophyll cell morphology through editing the potential target genes impacts leaf photosynthetic capacity and related physiological processes. This will pinpoint the targets for engineering leaf anatomy to maximize photosynthetic capacity.
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Affiliation(s)
- Tao Ren
- College of Resources and Environment, Huazhong Agricultural University, China
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, USA
| | - Sarathi M Weraduwage
- Department of Energy Plant Research Laboratory and Plant Resiience Institute, Michigan State University, East Lansing, USA
| | - Thomas D Sharkey
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, USA
- Department of Energy Plant Research Laboratory and Plant Resiience Institute, Michigan State University, East Lansing, USA
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13
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Abstract
Measurements of in vivo photosynthesis are powerful tools that probe the largest fluxes of carbon and energy in an illuminated leaf, but often the specific techniques used are so varied and specialized that it is difficult for researchers outside the field to select and perform the most useful assays for their research questions. The goal of this chapter is to provide a broad overview of the current tools available for the study of in vivo photosynthesis so as to provide a foundation for selecting appropriate techniques, many of which are presented in detail in subsequent chapters. This chapter also organizes current methods into a comparative framework and provides examples of how they have been applied to research questions of broad agronomical, ecological, or biological importance. The chapter closes with an argument that the future of in vivo measurements of photosynthesis lies in the ability to use multiple methods simultaneously and discusses the benefits of this approach to currently open physiological questions. This chapter, combined with the relevant methods chapters, could serve as a laboratory course in methods in photosynthesis research or as part of a more comprehensive laboratory course in general plant physiology methods.
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14
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Prieto I, Querejeta JI, Segrestin J, Volaire F, Roumet C. Leaf carbon and oxygen isotopes are coordinated with the leaf economics spectrum in Mediterranean rangeland species. Funct Ecol 2017. [DOI: 10.1111/1365-2435.13025] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Iván Prieto
- CEFECNRSUniv MontpellierUniv Paul Valéry Montpellier 3EPHEIRD Montpellier France
- Centro de Edafología y Biología Aplicada del Segura‐Consejo Superior de Investigaciones Científicas (CEBAS‐CSIC) Murcia Spain
| | - José I. Querejeta
- Centro de Edafología y Biología Aplicada del Segura‐Consejo Superior de Investigaciones Científicas (CEBAS‐CSIC) Murcia Spain
| | - Jules Segrestin
- CEFECNRSUniv MontpellierUniv Paul Valéry Montpellier 3EPHEIRD Montpellier France
| | - Florence Volaire
- CEFEINRACNRSUniv. MontpellierUniv Paul Valéry Montpellier 3EPHEIRD Montpellier France
| | - Catherine Roumet
- CEFECNRSUniv MontpellierUniv Paul Valéry Montpellier 3EPHEIRD Montpellier France
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Larkum AWD, Davey PA, Kuo J, Ralph PJ, Raven JA. Carbon-concentrating mechanisms in seagrasses. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:3773-3784. [PMID: 28911056 DOI: 10.1093/jxb/erx206] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Seagrasses are unique angiosperms that carry out growth and reproduction submerged in seawater. They occur in at least three families of the Alismatales. All have chloroplasts mainly in the cells of the epidermis. Living in seawater, the supply of inorganic carbon (Ci) to the chloroplasts is diffusion limited, especially under unstirred conditions. Therefore, the supply of CO2 and bicarbonate across the diffusive boundary layer on the outer side of the epidermis is often a limiting factor. Here we discuss the evidence for mechanisms that enhance the uptake of Ci into the epidermal cells. Since bicarbonate is plentiful in seawater, a bicarbonate pump might be expected; however, the evidence for such a pump is not strongly supported. There is evidence for a carbonic anhydrase outside the outer plasmalemma. This, together with evidence for an outward proton pump, suggests the possibility that local acidification leads to enhanced concentrations of CO2 adjacent to the outer tangential epidermal walls, which enhances the uptake of CO2, and this could be followed by a carbon-concentrating mechanism (CCM) in the cytoplasm and/or chloroplasts. The lines of evidence for such an epidermal CCM are discussed, including evidence for special 'transfer cells' in some but not all seagrass leaves in the tangential inner walls of the epidermal cells. It is concluded that seagrasses have a CCM but that the case for concentration of CO2 at the site of Rubisco carboxylation is not proven.
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Affiliation(s)
- Anthony William D Larkum
- Plant Functional Biology and Global Climate Change Cluster, University of Technology Sydney, NSW 2009, Australia
| | - Peter A Davey
- Plant Functional Biology and Global Climate Change Cluster, University of Technology Sydney, NSW 2009, Australia
| | - John Kuo
- Electron Microscope Centre, University of Western Australia, WA 6900, Australia
| | - Peter J Ralph
- Plant Functional Biology and Global Climate Change Cluster, University of Technology Sydney, NSW 2009, Australia
| | - John A Raven
- Plant Functional Biology and Global Climate Change Cluster, University of Technology Sydney, NSW 2009, Australia
- University of Dundee at JHI, Invergowrie, Dundee, UK
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