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Fang T, Jin G, Liu Z. Isotope-Based Techniques to Investigate Factors Influencing Water Use Efficiency in Pinus koraiensis Leaves during Plant Growth. PLANTS (BASEL, SWITZERLAND) 2024; 13:1771. [PMID: 38999611 PMCID: PMC11243977 DOI: 10.3390/plants13131771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2024] [Revised: 06/16/2024] [Accepted: 06/24/2024] [Indexed: 07/14/2024]
Abstract
Plant water use efficiency (WUE) is a comprehensive physiological indicator of plant growth and ability to adapt to drought. However, research on the mechanisms controlling WUE during plant growth and development remains weak. Here, we studied Pinus koraiensis as a typical evergreen conifer species in Northeast China. After collecting 80 tree samples with varying diameters at breast height (DBH), we measured δ13C and δ18O as an indicator of WUE, leaf morphology (volume, dry weight, and total epidermal area), ecological stoichiometry (carbon, nitrogen, and phosphorus content), and abiotic factors (light environment, soil pH, soil water content, and soil nutrient content). Correlational analysis of these variables revealed distinct differences between smaller/younger and larger/older plants: (1) In plants with DBH less than 52 cm, δ13C was positively related to DBH, and δ18O was negatively related to DBH. Plants with DBH greater than 52 cm showed no relationship between δ13C and DBH, and δ18O was positively related to DBH. (2) In plants with DBH less than 52 cm, there was a negative correlation between δ13C and δ18O and between δ13C and leaf phosphorus content (LP), but a positive correlation between δ13C and DBH, leaf mass per area (LMA), and leaf density (LD). The slopes of DBH-δ13C, δ18O-δ13C, leaf nitrogen content (LN)-δ13C, and LMA-δ13C correlations were greater in smaller plants than large plants. (3) Structural equation modelling showed that in smaller plants, DBH had a direct positive effect on δ13C content and a direct negative effect on δ18O, and there was a direct positive effect of light environment on δ18O. In larger plants, there was a direct negative effect of light environment on δ13C and a direct positive effect of DBH on light environment, as well as a negative effect of soil nitrogen content on leaf nitrogen. In smaller plants, DBH was the most important factor influencing δ13C, followed by δ18O and soil moisture, with light and soil pH showing minimal influence. In larger plants, light environment influenced δ13C the most, followed by soil nitrogen content and soil moisture content, with leaf nitrogen and DBH contributing little. The results suggest that water use efficiency strategies of P. koraiensis vary according to growth stage, and the effects of abiotic factors and functional traits vary at different growth stages.
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Affiliation(s)
- Tiantian Fang
- Center for Ecological Research, Northeast Forestry University, Harbin 150040, China
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, Northeast Forestry University, Harbin 150040, China
- Northeast Asia Biodiversity Research Center, Northeast Forestry University, Harbin 150040, China
| | - Guangze Jin
- Center for Ecological Research, Northeast Forestry University, Harbin 150040, China
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, Northeast Forestry University, Harbin 150040, China
- Northeast Asia Biodiversity Research Center, Northeast Forestry University, Harbin 150040, China
| | - Zhili Liu
- Center for Ecological Research, Northeast Forestry University, Harbin 150040, China
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, Northeast Forestry University, Harbin 150040, China
- Northeast Asia Biodiversity Research Center, Northeast Forestry University, Harbin 150040, China
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McElwain JC, Matthaeus WJ, Barbosa C, Chondrogiannis C, O' Dea K, Jackson B, Knetge AB, Kwasniewska K, Nair R, White JD, Wilson JP, Montañez IP, Buckley YM, Belcher CM, Nogué S. Functional traits of fossil plants. THE NEW PHYTOLOGIST 2024; 242:392-423. [PMID: 38409806 DOI: 10.1111/nph.19622] [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: 09/10/2023] [Accepted: 12/19/2023] [Indexed: 02/28/2024]
Abstract
A minuscule fraction of the Earth's paleobiological diversity is preserved in the geological record as fossils. What plant remnants have withstood taphonomic filtering, fragmentation, and alteration in their journey to become part of the fossil record provide unique information on how plants functioned in paleo-ecosystems through their traits. Plant traits are measurable morphological, anatomical, physiological, biochemical, or phenological characteristics that potentially affect their environment and fitness. Here, we review the rich literature of paleobotany, through the lens of contemporary trait-based ecology, to evaluate which well-established extant plant traits hold the greatest promise for application to fossils. In particular, we focus on fossil plant functional traits, those measurable properties of leaf, stem, reproductive, or whole plant fossils that offer insights into the functioning of the plant when alive. The limitations of a trait-based approach in paleobotany are considerable. However, in our critical assessment of over 30 extant traits we present an initial, semi-quantitative ranking of 26 paleo-functional traits based on taphonomic and methodological criteria on the potential of those traits to impact Earth system processes, and for that impact to be quantifiable. We demonstrate how valuable inferences on paleo-ecosystem processes (pollination biology, herbivory), past nutrient cycles, paleobiogeography, paleo-demography (life history), and Earth system history can be derived through the application of paleo-functional traits to fossil plants.
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Affiliation(s)
- Jennifer C McElwain
- School of Natural Sciences, Botany, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | - William J Matthaeus
- School of Natural Sciences, Botany, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | - Catarina Barbosa
- School of Natural Sciences, Botany, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | | | - Katie O' Dea
- School of Natural Sciences, Botany, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | - Bea Jackson
- School of Natural Sciences, Botany, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | - Antonietta B Knetge
- School of Natural Sciences, Botany, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | - Kamila Kwasniewska
- School of Natural Sciences, Botany, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | - Richard Nair
- School of Natural Sciences, Botany, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | - Joseph D White
- Department of Biology, Baylor University, Waco, 76798-7388, TX, USA
| | - Jonathan P Wilson
- Department of Environmental Studies, Haverford College, Haverford, Pennsylvania, 19041, PA, USA
| | - Isabel P Montañez
- UC Davis Institute of the Environment, University of California, Davis, CA, 95616, USA
- Department of Earth and Planetary Sciences, University of California, Davis, CA, 95616, USA
| | - Yvonne M Buckley
- School of Natural Sciences, Zoology, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | | | - Sandra Nogué
- Universitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), 08193, Catalonia, Spain
- CREAF, Bellaterra (Cerdanyola del Vallès), 08193, Catalonia, Spain
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Guo J, Beverly DP, Ewers BE, Williams DG. Stomatal, mesophyll and biochemical limitations to photosynthesis and their relationship with leaf structure over an elevation gradient in two conifers. PHOTOSYNTHESIS RESEARCH 2023; 157:85-101. [PMID: 37212937 DOI: 10.1007/s11120-023-01022-0] [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: 06/06/2022] [Accepted: 03/29/2023] [Indexed: 05/23/2023]
Abstract
Photosynthetic responses across complex elevational gradients provides insight into fundamental processes driving responses of plant growth and net primary production to environmental change. Gas exchange of needles and twig water potential were measured in two widespread coniferous tree species, Pinus contorta and Picea engelmannii, over an 800-m elevation gradient in southeastern Wyoming, USA. We hypothesized that limitations to photosynthesis imposed by mesophyll conductance (gm) would be greatest at the highest elevation sites due to higher leaf mass per area (LMA) and that estimations of maximum rate of carboxylation (Vcmax) without including gm would obscure elevational patterns of photosynthetic capacity. We found that gm decreased with elevation for P. contorta and remained constant for P. engelmannii, but in general, limitation to photosynthesis by gm was small. Indeed, estimations of Vcmax when including gm were equivalent to those estimated without including gm and no correlation was found between gm and LMA nor between gm and leaf N. Stomatal conductance (gs) and biochemical demand for CO2 were by far the most limiting processes to photosynthesis at all sites along the elevation gradient. Photosynthetic capacity (A) and gs were influenced strongly by differences in soil water availability across the elevation transect, while gm was less responsive to water availability. Based on our analysis, variation in gm plays only a minor role in driving patterns of photosynthesis in P. contorta and P. engelmannii across complex elevational gradients in dry, continental environments of the Rocky Mountains and accurate modeling of photosynthesis, growth and net primary production in these forests may not require detailed estimation of this trait value.
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Affiliation(s)
- Jiemin Guo
- Department of Botany, University of Wyoming, Laramie, WY, 82071, USA.
| | - Daniel P Beverly
- O'Neill School of Public and Environmental Affairs, Indiana University, Bloomington, IN, USA
- Biology Department, Indiana University, Bloomington, IN, USA
| | - Brent E Ewers
- Department of Botany, University of Wyoming, Laramie, WY, 82071, USA
| | - David G Williams
- Department of Botany, University of Wyoming, Laramie, WY, 82071, USA
- Department of Ecosystem Science and Management, University of Wyoming, Laramie, WY, 82071, USA
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Miyazawa SI, Ujino-Ihara T, Miyama T, Tahara K, Tobita H, Suzuki Y, Nishiguchi M. Different photorespiratory mechanisms in conifer leaves, where peroxisomes have intrinsically low catalase activity. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 115:1004-1020. [PMID: 37162489 DOI: 10.1111/tpj.16276] [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: 07/15/2022] [Revised: 04/28/2023] [Accepted: 05/03/2023] [Indexed: 05/11/2023]
Abstract
Photorespiration is an essential metabolic mechanism associated with photosynthesis; however, little is known about the photorespiratory pathway of conifer gymnosperms. Metabolite analyses of the leaves of 27 tree species showed that the mean glycerate content in conifer leaves was lower than that in angiosperm leaves. We performed experiments where [13 C]-serine was fed to detached shoots of a conifer (Cryptomeria japonica), via the transpiration stream, and compared the labeling patterns of photorespiratory metabolites with those of an angiosperm tree (Populus nigra), because glycerate is produced from serine via hydroxypyruvate in peroxisomes. In P. nigra, hydroxypyruvate, glycerate and glycine were labeled with 13 C, whereas in C. japonica, glycolate and a non-canonical photorespiratory metabolite, formate, were also labeled, suggesting that an H2 O2 -mediated non-enzymatic decarboxylation (NED) reaction occurs in C. japonica. We analyzed changes in the metabolite contents of leaves kept in the dark and leaves exposed to illuminated photorespiration-promoting conditions: a positive relationship between formate and serine levels in C. japonica implied that the active C1 -metabolism pathway synthesizes serine from formate. Leaf gas exchange analyses revealed that CO2 produced through NED was recaptured by chloroplasts. Database analysis of the peroxisomal targeting signal motifs of an H2 O2 -scavenging enzyme, catalase, derived from various species, including nine coniferous species, as well as analyses of peroxisomal fractions isolated from C. japonica and P. nigra leaves indicated that conifer peroxisomes had less catalase activity. These results suggest that NED and the subsequent C1 metabolism are involved in the photorespiratory pathway of conifer leaves, where peroxisomes have intrinsically low catalase activity.
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Affiliation(s)
- Shin-Ichi Miyazawa
- Department of Forest Molecular Genetics and Biotechnology, Forestry and Forest Products Research Institute (FFPRI), 1 Matsunosato, Tsukuba, Japan
| | - Tokuko Ujino-Ihara
- Department of Forest Molecular Genetics and Biotechnology, Forestry and Forest Products Research Institute (FFPRI), 1 Matsunosato, Tsukuba, Japan
| | - Takafumi Miyama
- Department of Disaster Prevention, Meteorology and Hydrology, Forestry and Forest Products Research Institute (FFPRI), 1 Matsunosato, Tsukuba, Japan
| | - Ko Tahara
- Department of Forest Molecular Genetics and Biotechnology, Forestry and Forest Products Research Institute (FFPRI), 1 Matsunosato, Tsukuba, Japan
| | - Hiroyuki Tobita
- Department of Plant Ecology, Forestry and Forest Products Research Institute (FFPRI), 1 Matsunosato, Tsukuba, Japan
| | - Yuji Suzuki
- Faculty of Agriculture, Iwate University, 3-18-8 Ueda, Morioka, Japan
| | - Mitsuru Nishiguchi
- Department of Forest Molecular Genetics and Biotechnology, Forestry and Forest Products Research Institute (FFPRI), 1 Matsunosato, Tsukuba, Japan
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Pang Y, Liao Q, Peng H, Qian C, Wang F. CO 2 mesophyll conductance regulated by light: a review. PLANTA 2023; 258:11. [PMID: 37289402 DOI: 10.1007/s00425-023-04157-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 04/17/2023] [Indexed: 06/09/2023]
Abstract
MAIN CONCLUSION Light quality and intensity regulate plant mesophyll conductance, which has played an essential role in photosynthesis by controlling leaf structural and biochemical properties. Mesophyll conductance (gm), a crucial physiological factor influencing the photosynthetic rate of leaves, is used to describe the resistance of CO2 from the sub-stomatal cavity into the chloroplast up to the carboxylation site. Leaf structural and biochemical components, as well as external environmental factors such as light, temperature, and water, all impact gm. As an essential factor of plant photosynthesis, light affects plant growth and development and plays a vital role in regulating gm as well as determining photosynthesis and yield. This review aimed to summarize the mechanisms of gm response to light. Both structural and biochemical perspectives were combined to reveal the effects of light quality and intensity on the gm, providing a guide for selecting the optimal conditions for intensifying photosynthesis in plants.
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Affiliation(s)
- Yadan Pang
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, 610213, China
- College of Horticulture and Landscape Architecture, Southwest University, Chongqing, 400712, China
| | - Qiuhong Liao
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, 610213, China
| | - Honggui Peng
- College of Horticulture and Landscape Architecture, Southwest University, Chongqing, 400712, China
| | - Chun Qian
- College of Horticulture and Landscape Architecture, Southwest University, Chongqing, 400712, China
| | - Fang Wang
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, 610213, China.
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Wang XQ, Sun H, Zeng ZL, Huang W. Within-branch photosynthetic gradients are more related to the coordinated investments of nitrogen and water than leaf mass per area. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 198:107681. [PMID: 37054614 DOI: 10.1016/j.plaphy.2023.107681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 03/18/2023] [Accepted: 04/03/2023] [Indexed: 05/07/2023]
Abstract
Nitrogen (N) and water are key resources for leaf photosynthesis and the growth of whole plants. Within-branch leaves need different amounts of N and water to support their differing photosynthetic capacities according to light exposure. To test this scheme, we measured the within-branch investments of N and water and their effects on photosynthetic traits in two deciduous tree species Paulownia tomentosa and Broussonetia papyrifera. We found that leaf photosynthetic capacity gradually increased from branch bottom to top (i.e. from shade to sun leaves). Concomitantly, stomatal conductance (gs) and leaf N content gradually increased, owing to the symport of water and inorganic mineral from root to leaf. Variation of leaf N content led to large gradients of mesophyll conductance, maximum velocity of Rubisco for carboxylation, maximum electron transport rate and leaf mass per area (LMA). Correlation analysis indicated that the within-branch difference in photosynthetic capacity was mainly related to gs and leaf N content, with a relatively minor contribution of LMA. Furthermore, the simultaneous increases of gs and leaf N content enhanced photosynthetic N use efficiency (PNUE) but hardly affected water use efficiency. Therefore, within-branch adjustment of N and water investments is an important strategy used by plants to optimize the overall photosynthetic carbon gain and PNUE.
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Affiliation(s)
- Xiao-Qian Wang
- Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Hu Sun
- Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhi-Lan Zeng
- Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wei Huang
- Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China.
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7
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Hanba YT, Nishida K, Tsutsui Y, Matsumoto M, Yasui Y, Sizhe Y, Matsuura T, Kawaguchi Akitsu T, Kume A. Leaf optical properties and photosynthesis of fern species with a wide range of divergence time in relation to mesophyll anatomy. ANNALS OF BOTANY 2023; 131:437-450. [PMID: 36749684 PMCID: PMC10072100 DOI: 10.1093/aob/mcad025] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 02/03/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND AND AIMS For a comprehensive understanding of the mechanisms of changing plant photosynthetic capacity during plant evolutionary history, knowledge of leaf gas exchange and optical properties are essential, both of which relate strongly to mesophyll anatomy. Although ferns are suitable for investigating the evolutionary history of photosynthetic capacity, comprehensive research of fern species has yet to be undertaken in this regard. METHODS We investigated leaf optical properties, gas exchange and mesophyll anatomy of fern species with a wide range of divergence time, using 66 ferns from natural habitats and eight glasshouse-grown ferns. We used a spectroradiometer and an integrating sphere to measure light absorptance and reflectance by the leaves. KEY RESULTS The more newly divergent fern species had a thicker mesophyll, a larger surface area of chloroplasts facing the intercellular airspaces (Sc), thicker cell walls and large light absorptance. Although no trend with divergence time was obtained in leaf photosynthetic capacity on a leaf-area basis, when the traits were expressed on a mesophyll-thickness basis, trends in leaf photosynthetic capacity became apparent. On a mesophyll-thickness basis, the more newly divergent species had a low maximum photosynthesis rate, accompanied by a low Sc. CONCLUSIONS We found a strong link between light capture, mesophyll anatomy and photosynthesis rate in fern species for the first time. The thick mesophyll of the more newly divergent ferns does not necessarily relate to the high photosynthetic capacity on a leaf-area basis. Rather, the thick mesophyll accompanied by thick cell walls allowed the ferns to adapt to a wider range of environments through increasing leaf toughness, which would contribute to the diversification of fern species.
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Affiliation(s)
- Yuko T Hanba
- Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Keisuke Nishida
- Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Yuuri Tsutsui
- Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Mayu Matsumoto
- Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Yutarou Yasui
- Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Yang Sizhe
- Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Takumi Matsuura
- Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Tomoko Kawaguchi Akitsu
- Earth Observation Research Center, Japan Aerospace Exploration Agency, 2-1-1 Sengen, Tsukuba 305-8505, Japan
| | - Atsushi Kume
- Faculty of Agriculture, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
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Pathare VS, DiMario RJ, Koteyeva N, Cousins AB. Mesophyll conductance response to short-term changes in pCO 2 is related to leaf anatomy and biochemistry in diverse C 4 grasses. THE NEW PHYTOLOGIST 2022; 236:1281-1295. [PMID: 35959528 PMCID: PMC9825963 DOI: 10.1111/nph.18427] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 07/31/2022] [Indexed: 06/15/2023]
Abstract
Mesophyll CO2 conductance (gm ) in C3 species responds to short-term (minutes) changes in environment potentially due to changes in leaf anatomical and biochemical properties and measurement artefacts. Compared with C3 species, there is less information on gm responses to short-term changes in environmental conditions such as partial pressure of CO2 (pCO2 ) across diverse C4 species and the potential determinants of these responses. Using 16 C4 grasses we investigated the response of gm to short-term changes in pCO2 and its relationship with leaf anatomy and biochemistry. In general, gm increased as pCO2 decreased (statistically significant increase in 12 species), with percentage increases in gm ranging from +13% to +250%. Greater increase in gm at low pCO2 was observed in species exhibiting relatively thinner mesophyll cell walls along with greater mesophyll surface area exposed to intercellular air spaces, leaf N, photosynthetic capacity and activities of phosphoenolpyruvate carboxylase and Rubisco. Species with greater CO2 responses of gm were also able to maintain their leaf water-use efficiencies (TEi ) under low CO2 . Our study advances understanding of CO2 response of gm in diverse C4 species, identifies the key leaf traits related to this response and has implications for improving C4 photosynthetic models and TEi through modification of gm .
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Affiliation(s)
- Varsha S. Pathare
- School of Biological SciencesWashington State UniversityPullmanWA99164‐4236USA
| | - Robert J. DiMario
- School of Biological SciencesWashington State UniversityPullmanWA99164‐4236USA
| | - Nuria Koteyeva
- School of Biological SciencesWashington State UniversityPullmanWA99164‐4236USA
- Laboratory of Anatomy and MorphologyV.L. Komarov Botanical Institute of the Russian Academy of Sciences197376St PetersburgRussia
| | - Asaph B. Cousins
- School of Biological SciencesWashington State UniversityPullmanWA99164‐4236USA
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Rivera BK, Sáez PL, Cavieres LA, Capó-Bauçà S, Iñiguez C, Sanfuentes von Stowasser E, Fuentes F, Ramírez CF, Vallejos V, Galmés J. Anatomical and biochemical evolutionary ancient traits of Araucaria araucana (Molina) K. Koch and their effects on carbon assimilation. TREE PHYSIOLOGY 2022; 42:1957-1974. [PMID: 35604362 DOI: 10.1093/treephys/tpac057] [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: 10/03/2021] [Accepted: 05/13/2022] [Indexed: 06/15/2023]
Abstract
The study of ancient species provides valuable information concerning the evolution of specific adaptations to past and current environmental conditions. Araucaria araucana (Molina) K. Koch belongs to one of the oldest families of conifers in the world, but despite this, there are few studies focused on its physiology and responses to changes in environmental conditions. We used an integrated approach aimed at comprehensively characterizing the ecophysiology of this poorly known species, focusing in its stomatal, mesophyll and biochemical traits, hypothesizing that these traits govern the carbon assimilation of A. araucana under past and present levels of atmospheric CO2. Results indicated that A. araucana presents the typical traits of an ancient species, such as large stomata and low stomatal density, which trigger low stomatal conductance and slow stomatal responsiveness to changing environmental conditions. Interestingly, the quantitative analysis showed that photosynthetic rates were equally limited by both diffusive and biochemical components. The Rubisco catalytic properties proved to have a low Rubisco affinity for CO2 and O2, similar to other ancient species. This affinity for CO2, together with the low carboxylation turnover rate, are responsible for the low Rubisco catalytic efficiency of carboxylation. These traits could be the result of the diverse environmental selective pressures that A. araucana was exposed during its diversification. The increase in measured temperatures induced an increase in stomatal and biochemical limitations, which together with a lower Rubisco affinity for CO2 could explain the low photosynthetic capacity of A. araucana in warmer conditions.
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Affiliation(s)
- Betsy K Rivera
- Laboratorio Cultivo de Tejidos Vegetales, Centro de Biotecnología, Departamento de Silvicultura, Facultad de Ciencias Forestales, Universidad de Concepción, Concepción 4030000, Chile
| | - Patricia L Sáez
- Laboratorio Cultivo de Tejidos Vegetales, Centro de Biotecnología, Departamento de Silvicultura, Facultad de Ciencias Forestales, Universidad de Concepción, Concepción 4030000, Chile
- Instituto de Ecología y Biodiversidad (IEB), Santiago 8320000, Chile
| | - Lohengrin A Cavieres
- Instituto de Ecología y Biodiversidad (IEB), Santiago 8320000, Chile
- ECOBIOSIS, Departamento de Botánica, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción 4030000, Chile
| | - Sebastià Capó-Bauçà
- Research Group on Plant Biology under Mediterranean Conditions, INAGEA-Universitat de les Illes Balears, Balearic Islands 07122, Spain
| | - Concepción Iñiguez
- Research Group on Plant Biology under Mediterranean Conditions, INAGEA-Universitat de les Illes Balears, Balearic Islands 07122, Spain
| | - Eugenio Sanfuentes von Stowasser
- Laboratorio de Patología Forestal, Facultad Ciencias Forestales y Centro de Biotecnología, Universidad de Concepción, Concepción 4030000, Chile
| | - Francisca Fuentes
- Laboratorio Cultivo de Tejidos Vegetales, Centro de Biotecnología, Departamento de Silvicultura, Facultad de Ciencias Forestales, Universidad de Concepción, Concepción 4030000, Chile
| | - Constanza F Ramírez
- Laboratorio Cultivo de Tejidos Vegetales, Centro de Biotecnología, Departamento de Silvicultura, Facultad de Ciencias Forestales, Universidad de Concepción, Concepción 4030000, Chile
| | - Valentina Vallejos
- Laboratorio Cultivo de Tejidos Vegetales, Centro de Biotecnología, Departamento de Silvicultura, Facultad de Ciencias Forestales, Universidad de Concepción, Concepción 4030000, Chile
| | - Jeroni Galmés
- Research Group on Plant Biology under Mediterranean Conditions, INAGEA-Universitat de les Illes Balears, Balearic Islands 07122, Spain
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Alonso-Forn D, Peguero-Pina JJ, Ferrio JP, García-Plazaola JI, Martín-Sánchez R, Niinemets Ü, Sancho-Knapik D, Gil-Pelegrín E. Cell-level anatomy explains leaf age-dependent declines in mesophyll conductance and photosynthetic capacity in the evergreen Mediterranean oak Quercus ilex subsp. rotundifolia. TREE PHYSIOLOGY 2022; 42:1988-2002. [PMID: 35451029 DOI: 10.1093/treephys/tpac049] [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: 01/11/2022] [Accepted: 04/13/2022] [Indexed: 06/14/2023]
Abstract
Leaves of Mediterranean evergreen tree species experience a reduction in net CO2 assimilation (AN) and mesophyll conductance to CO2 (gm) during aging and senescence, which would be influenced by changes in leaf anatomical traits at cell level. Anatomical modifications can be accompanied by the dismantling of photosynthetic apparatus associated to leaf senescence, manifested through changes at the biochemical level (i.e., lower nitrogen investment in photosynthetic machinery). However, the role of changes in leaf anatomy at cell level and nitrogen content in gm and AN decline experienced by old non-senescent leaves of evergreen trees with long leaf lifespan is far from being elucidated. We evaluated age-dependent changes in morphological, anatomical, chemical and photosynthetic traits in Quercus ilex subsp. rotundifolia Lam., an evergreen oak with high leaf longevity. All photosynthetic traits decreased with increasing leaf age. The relative change in cell wall thickness (Tcw) was less than in chloroplast surface area exposed to intercellular air space (Sc/S), and Sc/S was a key anatomical trait explaining variations in gm and AN among different age classes. The reduction of Sc/S was related to ultrastructural changes in chloroplasts associated to leaf aging, with a concomitant reduction in cytoplasmic nitrogen. Changes in leaf anatomy and biochemistry were responsible for the age-dependent modifications in gm and AN. These findings revealed a gradual physiological deterioration related to the dismantling of the photosynthetic apparatus in older leaves of Q. ilex subsp. rotundifolia.
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Affiliation(s)
- David Alonso-Forn
- Departamento de Sistemas Agrícolas, Forestales y Medio Ambiente, Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), Avda Montañana 930, Zaragoza 50059, Spain
| | - José Javier Peguero-Pina
- Departamento de Sistemas Agrícolas, Forestales y Medio Ambiente, Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), Avda Montañana 930, Zaragoza 50059, Spain
- Instituto Agroalimentario de Aragón -IA2- (CITA-Universidad de Zaragoza), Zaragoza, Spain
| | - Juan Pedro Ferrio
- Departamento de Sistemas Agrícolas, Forestales y Medio Ambiente, Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), Avda Montañana 930, Zaragoza 50059, Spain
- Aragon Agency for Research and Development (ARAID), Zaragoza E-50018, Spain
| | - José Ignacio García-Plazaola
- Department of Plant Biology and Ecology, University of the Basque Country (UPV/EHU), Apdo 644, Bilbao 48080, Spain
| | - Rubén Martín-Sánchez
- Departamento de Sistemas Agrícolas, Forestales y Medio Ambiente, Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), Avda Montañana 930, Zaragoza 50059, Spain
| | - Ülo Niinemets
- Crop Science and Plant Biology, Estonian University of Life Sciences, Kreutzwaldi 1, 51006 Tartu, Estonia
| | - Domingo Sancho-Knapik
- Departamento de Sistemas Agrícolas, Forestales y Medio Ambiente, Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), Avda Montañana 930, Zaragoza 50059, Spain
- Instituto Agroalimentario de Aragón -IA2- (CITA-Universidad de Zaragoza), Zaragoza, Spain
| | - Eustaquio Gil-Pelegrín
- Departamento de Sistemas Agrícolas, Forestales y Medio Ambiente, Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), Avda Montañana 930, Zaragoza 50059, Spain
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11
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Haworth M, Marino G, Loreto F, Centritto M. The evolution of diffusive and biochemical capacities for photosynthesis was predominantly shaped by [CO 2] with a smaller contribution from [O 2]. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 840:156606. [PMID: 35691351 DOI: 10.1016/j.scitotenv.2022.156606] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 05/18/2022] [Accepted: 06/06/2022] [Indexed: 06/15/2023]
Abstract
The atmospheric concentration of carbon dioxide ([CO2]) and oxygen ([O2]) directly influence rates of photosynthesis (PN) and photorespiration (RPR) through the enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO). Levels of [CO2] and [O2] have varied over Earth history affecting rates of both CO2 uptake and loss, alongside associated transpirative water-loss. The availability of CO2 has likely acted as a stronger selective pressure than [O2] due to the greater specificity of RubisCO for CO2. The role of [O2], and the interaction of [O2] and [CO2], in plant evolutionary history is less understood. We exposed twelve phylogenetically diverse species to combinations of sub-ambient, ambient and super-ambient [O2] and [CO2] to examine the biochemical and diffusive components of PN and the possible role of [O2] as a selective pressure. Photosynthesis, photosynthetic capacity and stomatal, mesophyll and total conductance to CO2 were higher in the derived eudicot and monocot angiosperms than the more basal ferns, gymnosperms and basal angiosperms which originated in atmospheres characterised by higher CO2:O2 ratios. The ratio of RPR:PN was lower in the monocots, consistent with greater carboxylation capacity and higher stomatal and mesophyll conductance making easier CO2 delivery to chloroplasts. The effect of [O2] and [CO2] on PN/RPR was less evident in more derived species with a higher conductance to CO2. The effect of [O2] was less apparent at high [CO2], suggesting that atmospheric [O2] may only have exerted a strong selective pressure on plant photosynthetic processes during periods characterised by low atmospheric CO2:O2 ratios. Current rising [CO2] will predominantly enhance PN rates in species with low diffusive conductance to CO2.
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Affiliation(s)
- Matthew Haworth
- National Research Council of Italy - Institute of Sustainable Plant Protection (CNR - IPSP), Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy.
| | - Giovanni Marino
- National Research Council of Italy - Institute of Sustainable Plant Protection (CNR - IPSP), Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy
| | - Francesco Loreto
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Mauro Centritto
- National Research Council of Italy - Institute of Sustainable Plant Protection (CNR - IPSP), Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy; ENI-CNR Water Research Centre "Hypatia of Alexandria", Research Centre Metapontum Agrobios, Metaponto, Italy
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12
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Mizokami Y, Oguchi R, Sugiura D, Yamori W, Noguchi K, Terashima I. Cost-benefit analysis of mesophyll conductance: diversities of anatomical, biochemical and environmental determinants. ANNALS OF BOTANY 2022; 130:265-283. [PMID: 35947983 PMCID: PMC9487971 DOI: 10.1093/aob/mcac100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 08/08/2022] [Indexed: 06/09/2023]
Abstract
BACKGROUND Plants invest photosynthates in construction and maintenance of their structures and functions. Such investments are considered costs. These costs are recovered by the CO2 assimilation rate (A) in the leaves, and thus A is regarded as the immediate, short-term benefit. In photosynthesizing leaves, CO2 diffusion from the air to the carboxylation site is hindered by several structural and biochemical barriers. CO2 diffusion from the intercellular air space to the chloroplast stroma is obstructed by the mesophyll resistance. The inverses is the mesophyll conductance (gm). Whether various plants realize an optimal gm, and how much investment is needed for a relevant gm, remain unsolved. SCOPE This review examines relationships among leaf construction costs (CC), leaf maintenance costs (MC) and gm in various plants under diverse growth conditions. Through a literature survey, we demonstrate a strong linear relationship between leaf mass per area (LMA) and leaf CC. The overall correlation of CC vs. gm across plant phylogenetic groups is weak, but significant trends are evident within specific groups and/or environments. Investment in CC is necessary for an increase in LMA and mesophyll cell surface area (Smes). This allows the leaf to accommodate more chloroplasts, thus increasing A. However, increases in LMA and/or Smes often accompany other changes, such as cell wall thickening, which diminishes gm. Such factors that make the correlations of CC and gm elusive are identified. CONCLUSIONS For evaluation of the contribution of gm to recover CC, leaf life span is the key factor. The estimation of MC in relation to gm, especially in terms of costs required to regulate aquaporins, could be essential for efficient control of gm over the short term. Over the long term, costs are mainly reflected in CC, while benefits also include ultimate fitness attributes in terms of integrated carbon gain over the life of a leaf, plant survival and reproductive output.
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Affiliation(s)
- Yusuke Mizokami
- Department of Life Science, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192-0392, Japan
| | - Riichi Oguchi
- Department of Biological Sciences, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Daisuke Sugiura
- Graduate School of Bioagricultural Sciences, Nagoya University, Furo, Chikusa-ku, Nagoya 464-8601, Japan
| | - Wataru Yamori
- Graduate School of Agricultural and Life Science, Institute for Sustainable Agri-ecosystem, The University of Tokyo, 1-1-1, Midoricho, Nishitokyo, Tokyo 188-0002, Japan
| | - Ko Noguchi
- Department of Life Science, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192-0392, Japan
| | - Ichiro Terashima
- Department of Biological Sciences, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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13
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Joffe R, Berthe A, Jolivet Y, Gandin A. The response of mesophyll conductance to ozone-induced oxidative stress is genotype-dependent in poplar. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:4850-4866. [PMID: 35429268 DOI: 10.1093/jxb/erac154] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 04/14/2022] [Indexed: 06/14/2023]
Abstract
The CO2 diffusion conductance within the leaf mesophyll (gm) is considered a major limiting factor of photosynthesis. However, the effects of the major secondary air pollutant ozone (O3) on gm have been poorly investigated. Eight genotypes of the economically important tree species Populus × canadensis Moench were exposed to 120 ppb O3 for 21 d. gm showed a genotype-dependent response to O3-induced oxidative stress and was a major limiting factor of net assimilation rate (Anet), ahead of stomatal conductance to CO2 (gsc) and of the maximum carboxylation capacity of the Rubisco enzyme (Vcmax) in half of the tested genotypes. Increased leaf dry mass per area (LMA) and decreased chlorophyll content were linked to the observed gm decrease, but this relationship did not entirely explain the different genotypic gm responses. Moreover, the oxidative stress defence metabolites ascorbate and glutathione were not related to O3 tolerance of gm. However, malondialdehyde probably mitigated the observed gm decrease in some genotypes due to its oxidative stress signalling function. The large variation of gm suggests different regulation mechanisms amongst poplar genotypes under oxidative stress.
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Affiliation(s)
- Ricardo Joffe
- Université de Lorraine, AgroParisTech, INRAE, SILVA, F-54000 Nancy, France
| | - Audrey Berthe
- Université de Lorraine, AgroParisTech, INRAE, SILVA, F-54000 Nancy, France
| | - Yves Jolivet
- Université de Lorraine, AgroParisTech, INRAE, SILVA, F-54000 Nancy, France
| | - Anthony Gandin
- Université de Lorraine, AgroParisTech, INRAE, SILVA, F-54000 Nancy, France
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14
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Perera-Castro AV, Waterman MJ, Robinson SA, Flexas J. Limitations to photosynthesis in bryophytes: certainties and uncertainties regarding methodology. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:4592-4604. [PMID: 35524766 DOI: 10.1093/jxb/erac189] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 05/05/2022] [Indexed: 06/14/2023]
Abstract
Bryophytes are the group of land plants with the lowest photosynthetic rates, which was considered to be a consequence of their higher anatomical CO2 diffusional limitation compared with tracheophytes. However, the most recent studies assessing limitations due to biochemistry and mesophyll conductance in bryophytes reveal discrepancies based on the methodology used. In this study, we compared data calculated from two different methodologies for estimating mesophyll conductance: variable J and the curve-fitting method. Although correlated, mesophyll conductance estimated by the curve-fitting method was on average 4-fold higher than the conductance obtained by the variable J method; a large enough difference to account for the scale of differences previously shown between the biochemical and diffusional limitations to photosynthesis. Biochemical limitations were predominant when the curve-fitting method was used. We also demonstrated that variations in bryophyte relative water content during measurements can also introduce errors in the estimation of mesophyll conductance, especially for samples which are overly desiccated. Furthermore, total chlorophyll concentration and soluble proteins were significantly lower in bryophytes than in tracheophytes, and the percentage of proteins quantified as Rubisco was also significantly lower in bryophytes (<6.3% in all studied species) than in angiosperms (>16% in all non-stressed cases). Photosynthetic rates normalized by Rubisco were not significantly different between bryophytes and angiosperms. Our data suggest that the biochemical limitation to photosynthesis in bryophytes is more relevant than so far assumed.
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Affiliation(s)
- Alicia V Perera-Castro
- Universitat de les Illes Balears, Department of Biology, INAGEA, Carretera de Valldemossa Km 7.5, 07122, Palma de Mallorca, Illes Balears, Spain
- Universidad de La Laguna, Department of Botany, Ecology and Plant Physiology, Av. Astrofísico Francisco Sánchez, S/N, 38200 La Laguna, Canary Islands, Spain
| | - Melinda J Waterman
- Centre for Sustainable Ecosystem Solutions, School of Earth, Atmosphere and Life Sciences, University of Wollongong, Wollongong, NSW, Australia
- Securing Antarctica's Environmental Future, University of Wollongong, Wollongong, NSW, Australia
| | - Sharon A Robinson
- Centre for Sustainable Ecosystem Solutions, School of Earth, Atmosphere and Life Sciences, University of Wollongong, Wollongong, NSW, Australia
- Securing Antarctica's Environmental Future, University of Wollongong, Wollongong, NSW, Australia
| | - Jaume Flexas
- Universitat de les Illes Balears, Department of Biology, INAGEA, Carretera de Valldemossa Km 7.5, 07122, Palma de Mallorca, Illes Balears, Spain
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15
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Zou J, Hu W, Li Y, Zhu H, He J, Wang Y, Meng Y, Chen B, Zhao W, Wang S, Zhou Z. Leaf anatomical alterations reduce cotton's mesophyll conductance under dynamic drought stress conditions. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 111:391-405. [PMID: 35506315 DOI: 10.1111/tpj.15794] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 03/25/2022] [Accepted: 04/29/2022] [Indexed: 06/14/2023]
Abstract
Drought stress significantly affects cotton's net photosynthetic rate (A) by restraining stomatal (gs ) and mesophyll conductance (gm ) as well as perturbing its biochemical process, resulting in yield reductions. Despite the significant progress in dissecting effects of drought on photosynthesis, the variability observed in cotton's gm , and the mechanisms contributing to that variability under dynamic drought stress conditions are poorly understood. For that reason, a controlled-environment experiment with two cotton genotypes (Dexiamian 1, Yuzaomian 9110), three water levels (soil relative water content: control [75 ± 5]%, moderate drought [60 ± 5]%, severe drought [45 ± 5]%), and two drought durations (10 and 31 days) were conducted. The results indicated that the cotton boll biomass was significantly decreased under 10-day severe drought and 31-day moderate and severe drought. Decreases in gs were later accompanied by decreases in gm and further combined with reductions in electron transport rate, as drought stress progressed in duration and severity, ultimately resulting in significant reductions in A of subtending leaf. Stomatal and mesophyll conductance constraints were the primary factors limiting photosynthesis, while biochemical constraints decreased, as drought stress progressed. Considering gm , its decline was ascribed to increases in the diffusion resistance of CO2 through cytoplasm (rcyt ), under short- or long-term drought, as well as to increases in leaf dry mass (LMA), and decreases in the chloroplast surface area exposed to intercellular air space (Sc /S), under long-term drought. It was concluded that A could be enhanced, under dynamic drought stress conditions, by increasing gm through increasing Sc /S and reducing LMA and rcyt .
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Affiliation(s)
- Jie Zou
- College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu Province, 210095, People's Republic of China
| | - Wei Hu
- College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu Province, 210095, People's Republic of China
| | - Yuxia Li
- College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu Province, 210095, People's Republic of China
| | - Honghai Zhu
- College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu Province, 210095, People's Republic of China
| | - Jiaqi He
- College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu Province, 210095, People's Republic of China
| | - Youhua Wang
- College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu Province, 210095, People's Republic of China
| | - Yali Meng
- College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu Province, 210095, People's Republic of China
| | - Binglin Chen
- College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu Province, 210095, People's Republic of China
| | - Wenqing Zhao
- College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu Province, 210095, People's Republic of China
| | - Shanshan Wang
- College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu Province, 210095, People's Republic of China
| | - Zhiguo Zhou
- College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu Province, 210095, People's Republic of China
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16
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Abdallah M, Douthe C, Flexas J. Leaf morpho-physiological comparison between native and non-native plant species in a Mediterranean island. Biol Invasions 2022. [DOI: 10.1007/s10530-022-02797-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
AbstractIslands tend to be more prone to plant invasions than mainland regions, with the Mediterranean ones not being an exception. So far, a large number of studies on comparing leaf morphological and physiological traits between native and non-native plants in Mediterranean environments have been performed, although none of them on Mediterranean islands. To fill this gap, this study focuses on 14 plant species grown in a controlled growth chamber in the absence of stress. The goal was (1) to differentiate leaf morpho-physiological traits between native and non-native plants on a Mediterranean island and (2) to deepen in the underlying causes of the differential photosynthetic traits displayed by non-native species. Results showed that in Mediterranean islands, non-native plant species show on average larger values of net CO2 assimilation, stomatal conductance (gm), photosynthetic nitrogen-use efficiency, among others, and lower leaf mass per area (LMA) and leaf thickness, compared to the native species. Among the assessed traits, this study reports for the first time larger gm, and lower mesophyll conductance limitation in non-native species, which seems to be linked to their lower LMA. These novel traits need to be added to the ‘leaf physiological trait invasive syndrome’. It was also found that on a Mediterranean island, native and non-native species are placed on opposite sides of the leaf economics spectrum, with non-native species being placed on the ‘‘fast-return’’ end. In conclusion, this study demonstrates that non-native species inhabiting a Mediterranean island possess distinct leaf morphological and physiological traits compared to co-occurring native species, at least during the favorable growth season, which increases the chances of a successful invasion.
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17
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Yang Q, Ravnskov S, Pullens JWM, Andersen MN. Interactions between biochar, arbuscular mycorrhizal fungi and photosynthetic processes in potato (Solanum tuberosum L.). THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 816:151649. [PMID: 34785223 DOI: 10.1016/j.scitotenv.2021.151649] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 10/25/2021] [Accepted: 11/09/2021] [Indexed: 06/13/2023]
Abstract
Pyrolyzed biomass, generating biochar for use as soil amendment, is recognized as a promising strategy for carbon sequestration. Current understanding of the interactions between biochar, arbuscular mycorrhizal (AM), and plant photosynthesis, in terms of biochemical processes and CO2 uptake, is fragmentary. The aim of this study was to investigate the effects on photosynthesis in potato including maximum rate of carboxylation by Rubisco (Vcmax), maximum rate of electron transport rate for RuBP-regeneration (Jmax), mesophyll conductance (gm) and other plant traits. Four types of biochar (wheat or miscanthus straw pellets pyrolyzed at temperatures of either 550 °C or 700 °C) were amended into low phosphorus soil. Potato plants were inoculated with the AM fungus Rhizophagus irregularis (M+) or not (M-). The results showed that four types of biochar generally decreased nitrogen and phosphorus content of potato, especially the biochars pyrolyzed at high temperature. This negative effect of biochar on nutrient content was alleviated by AM. It was found that Vcmax was limited by low plant nitrogen content as well as leaf area and phosphorus content. Plant phosphorus content also limited Jmax, which was mutually constrained by Vcmax of leaves. Low gm was an additional limiting factor for photosynthesis. The gm was positively correlated to nitrogen content, which influenced the leaf anatomical structure by alteration of leaf mass per area. In conclusion, the influence of interactions between quality of biochar and AM symbiosis on photosynthesis of potato seems to relate to effects on plant nutrient content and leaf structures. Accordingly, a model for the dependence of Vcmax on nitrogen and phosphorus content and their interactive effect exhibited a high correlation coefficient. As potato plants form AM symbiosis under natural field conditions, the extent and interaction with the quality of amended biochar can be a determining factor for plant nutrient content, growth and yield.
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Affiliation(s)
- Qi Yang
- Department of Agroecology, Faculty of Science and Technology, Aarhus University, Blichers Allé 20, 8830 Tjele, Denmark.
| | - Sabine Ravnskov
- Department of Agroecology, Faculty of Science and Technology, Aarhus University, Blichers Allé 20, 8830 Tjele, Denmark
| | | | - Mathias Neumann Andersen
- Department of Agroecology, Faculty of Science and Technology, Aarhus University, Blichers Allé 20, 8830 Tjele, Denmark
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18
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Khoshravesh R, Hoffmann N, Hanson DT. Leaf microscopy applications in photosynthesis research: identifying the gaps. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:1868-1893. [PMID: 34986250 DOI: 10.1093/jxb/erab548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 12/10/2021] [Indexed: 06/14/2023]
Abstract
Leaf imaging via microscopy has provided critical insights into research on photosynthesis at multiple junctures, from the early understanding of the role of stomata, through elucidating C4 photosynthesis via Kranz anatomy and chloroplast arrangement in single cells, to detailed explorations of diffusion pathways and light utilization gradients within leaves. In recent decades, the original two-dimensional (2D) explorations have begun to be visualized in three-dimensional (3D) space, revising our understanding of structure-function relationships between internal leaf anatomy and photosynthesis. In particular, advancing new technologies and analyses are providing fresh insight into the relationship between leaf cellular components and improving the ability to model net carbon fixation, water use efficiency, and metabolite turnover rate in leaves. While ground-breaking developments in imaging tools and techniques have expanded our knowledge of leaf 3D structure via high-resolution 3D and time-series images, there is a growing need for more in vivo imaging as well as metabolite imaging. However, these advances necessitate further improvement in microscopy sciences to overcome the unique challenges a green leaf poses. In this review, we discuss the available tools, techniques, challenges, and gaps for efficient in vivo leaf 3D imaging, as well as innovations to overcome these difficulties.
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Affiliation(s)
| | - Natalie Hoffmann
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada
| | - David T Hanson
- Department of Biology, University of New Mexico, Albuquerque, NM, USA
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19
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Lei Z, Liu F, Wright IJ, Carriquí M, Niinemets Ü, Han J, Jia M, Atwell BJ, Cai X, Zhang W, Zhou Z, Zhang Y. Comparisons of photosynthetic and anatomical traits between wild and domesticated cotton. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:873-885. [PMID: 34153103 DOI: 10.1093/jxb/erab293] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 06/19/2021] [Indexed: 06/13/2023]
Abstract
Mesophyll conductance (gm) is a crucial leaf trait contributing to the photosynthetic rate (AN). Plant domestication typically leads to an enhancement of AN that is often associated with profound anatomical modifications, but it is unclear which of these structural alterations influence gm. We analyzed the implication of domestication on leaf anatomy and its effect on gm in 26 wild and 31 domesticated cotton genotypes (Gossypium sp.) grown under field conditions. We found that domesticated genotypes had higher AN but similar gm to wild genotypes. Consistent with this, domestication did not translate into significant differences in the fraction of mesophyll occupied by intercellular air spaces (fias) or mesophyll and chloroplast surface area exposed to intercellular air space (Sm/S and Sc/S, respectively). However, leaves of domesticated genotypes were significantly thicker, with larger but fewer mesophyll cells with thinner cell walls. Moreover, domesticated genotypes had higher cell wall conductance (gcw) but smaller cytoplasmic conductance (gcyt) than wild genotypes. It appears that domestication in cotton has not generally led to significant improvement in gm, in part because their thinner mesophyll cell walls (increasing gcw) compensate for their lower gcyt, itself due to larger distance between plasmalemma and chloroplast envelopes.
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Affiliation(s)
- Zhangying Lei
- The Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Group, Shihezi University, Shihezi, 832003, PR China
- Department of Biological Sciences, Macquarie University, North Ryde, NSW 2109, Australia
| | - Fang Liu
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, PR China
| | - Ian J Wright
- Department of Biological Sciences, Macquarie University, North Ryde, NSW 2109, Australia
| | - Marc Carriquí
- School of Natural Sciences, University of Tasmania, Bag 55, 7001 Hobart, Tasmania, Australia
| | - Ülo Niinemets
- Chair of Crop Science and Plant Biology, Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 1, 51006 Tartu, Estonia
| | - Jimei Han
- School of Integrative Plant Science, Soil and Crop Science Section, Cornell University, Ithaca, NY 14850, USA
| | - Mengmeng Jia
- The Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Group, Shihezi University, Shihezi, 832003, PR China
| | - Brian J Atwell
- Department of Biological Sciences, Macquarie University, North Ryde, NSW 2109, Australia
| | - Xiaoyan Cai
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, PR China
| | - Wangfeng Zhang
- The Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Group, Shihezi University, Shihezi, 832003, PR China
| | - Zhongli Zhou
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, PR China
| | - Yali Zhang
- The Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Group, Shihezi University, Shihezi, 832003, PR China
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Ulloa M, Nunes-Nesi A, da Fonseca-Pereira P, Poblete-Grant P, Reyes-Díaz M, Cartes P. The effect of silicon supply on photosynthesis and carbohydrate metabolism in two wheat (Triticum aestivum L.) cultivars contrasting in response to phosphorus nutrition. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2021; 169:236-248. [PMID: 34808466 DOI: 10.1016/j.plaphy.2021.11.022] [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: 08/05/2021] [Revised: 11/09/2021] [Accepted: 11/11/2021] [Indexed: 06/13/2023]
Abstract
Phosphorus (P) deficiency affects agricultural systems by limiting crop quality and yield. Studies have suggested that silicon (Si) improves P uptake in plants grown under P deficiency. However, the effects of Si on photosynthesis and carbohydrate metabolism under P stress remain unclear. We performed a hydroponic study using two wheat cultivars with contrasting sensitivity to P deficiency (Púrpura, sensitive; Fritz, semi-tolerant) that were exposed to P (0, 0.01, or 0.1 mM) and Si (0 or 2 mM), and we evaluated the photosynthetic performance and metabolic alterations. In plants from the sensitive cultivar undergoing P deficiency, Si application increased sucrose levels, starch breakdown and length of shoots, and also improved plant dry weight. In Fritz (the semi-tolerant cultivar), Si exposure reduced P concentration, and increased shoot length and P use efficiency (PUE) under P shortage. Interestingly, Si application altered cell wall composition, which was associated with higher mesophyll conductance and net CO2 assimilation in Fritz plants grown under P stress. Together, our results indicate that under P deficiency, Si nutrition positively affects photosynthesis and carbohydrate levels in a genotype-dependent manner. Furthermore, these results suggest that Si plays an important role in maintaining high photosynthetic rates in wheat plants undergoing P deficiency.
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Affiliation(s)
- Marlys Ulloa
- Doctoral Program in Science of Natural Resources, Universidad de La Frontera, Avenida Francisco Salazar 01145, P.O. Box 54-D, Temuco, 4780000, Chile; Center of Plant, Soil Interaction and Natural Resources Biotechnology, Scientific and Biotechnological Bioresource Nucleus (BIOREN-UFRO), Universidad de La Frontera, Avenida Francisco Salazar 01145, PO Box 54-D, Temuco, 4780000, Chile
| | - Adriano Nunes-Nesi
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, MG, Brazil
| | | | - Patricia Poblete-Grant
- Center of Plant, Soil Interaction and Natural Resources Biotechnology, Scientific and Biotechnological Bioresource Nucleus (BIOREN-UFRO), Universidad de La Frontera, Avenida Francisco Salazar 01145, PO Box 54-D, Temuco, 4780000, Chile
| | - Marjorie Reyes-Díaz
- Center of Plant, Soil Interaction and Natural Resources Biotechnology, Scientific and Biotechnological Bioresource Nucleus (BIOREN-UFRO), Universidad de La Frontera, Avenida Francisco Salazar 01145, PO Box 54-D, Temuco, 4780000, Chile; Departamento de Ciencias Químicas y Recursos Naturales, Facultad de Ingeniería y Ciencias, Universidad de La Frontera, Avenida Francisco Salazar 01145, PO Box 54-D, Temuco, 4780000, Chile
| | - Paula Cartes
- Center of Plant, Soil Interaction and Natural Resources Biotechnology, Scientific and Biotechnological Bioresource Nucleus (BIOREN-UFRO), Universidad de La Frontera, Avenida Francisco Salazar 01145, PO Box 54-D, Temuco, 4780000, Chile; Departamento de Ciencias Químicas y Recursos Naturales, Facultad de Ingeniería y Ciencias, Universidad de La Frontera, Avenida Francisco Salazar 01145, PO Box 54-D, Temuco, 4780000, Chile.
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21
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Coiro M, Barone Lumaga MR, Rudall PJ. Stomatal development in the cycad family Zamiaceae. ANNALS OF BOTANY 2021; 128:577-588. [PMID: 34265043 PMCID: PMC8422890 DOI: 10.1093/aob/mcab095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Accepted: 07/10/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND AND AIMS The gymnosperm order Cycadales is pivotal to our understanding of seed-plant phylogeny because of its phylogenetic placement close to the root node of extant spermatophytes and its combination of both derived and plesiomorphic character states. Although widely considered a 'living fossil' group, extant cycads display a high degree of morphological and anatomical variation. We investigate stomatal development in Zamiaceae to evaluate variation within the order and homologies between cycads and other seed plants. METHODS Leaflets of seven species across five genera representing all major clades of Zamiaceae were examined at various stages of development using light microscopy and confocal microscopy. KEY RESULTS All genera examined have lateral subsidiary cells of perigenous origin that differ from other pavement cells in mature leaflets and could have a role in stomatal physiology. Early epidermal patterning in a 'quartet' arrangement occurs in Ceratozamia, Zamia and Stangeria. Distal encircling cells, which are sclerified at maturity, are present in all genera except Bowenia, which shows relatively rapid elongation and differentiation of the pavement cells during leaflet development. CONCLUSIONS Stomatal structure and development in Zamiaceae highlights some traits that are plesiomorphic in seed plants, including the presence of perigenous encircling subsidiary cells, and reveals a clear difference between the developmental trajectories of cycads and Bennettitales. Our study also shows an unexpected degree of variation among subclades in the family, potentially linked to differences in leaflet development and suggesting convergent evolution in cycads.
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Affiliation(s)
- Mario Coiro
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland
- Ronin Institute for Independent Scholarship, Montclair, NJ, USA
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22
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Eckert D, Martens HJ, Gu L, Jensen AM. CO2 refixation is higher in leaves of woody species with high mesophyll and stomatal resistances to CO2 diffusion. TREE PHYSIOLOGY 2021; 41:1450-1461. [PMID: 33595079 PMCID: PMC8359682 DOI: 10.1093/treephys/tpab016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 11/30/2020] [Accepted: 01/18/2021] [Indexed: 06/12/2023]
Abstract
The percentage of respiratory and photorespiratory CO2 refixed in leaves (Pr) represents part of the CO2 used in photosynthesis. The importance of Pr as well as differences between species and functional types are still not well investigated. In this study, we examine how Pr differs between six temperate and boreal woody species: Betula pendula, Quercus robur, Larix decidua, Pinus sylvestris, Picea abies and Vaccinium vitis-idaea. The study covers early and late successional species, deciduous broadleaves, deciduous conifers, evergreen conifers and evergreen broadleaves. We investigated whether some species or functional types had higher refixation percentages than others, whether leaf traits could predict higher Pr and whether these traits and their impact on Pr changed during growing seasons. Photosynthesis CO2 response (A/Ci)-curves, measured early, mid and late season, were used to estimate and compare Pr, mesophyll resistance (rm) and stomatal resistance (rs) to CO2 diffusion. Additionally, light images and transmission electron microscope images were used to approximate the fraction of intercellular airspace and cell wall thickness. We found that evergreens, especially late successional species, refixed a significantly higher amount of CO2 than the other species throughout the entire growing season. In addition, rm, rs and leaf mass per area, traits that typically are higher in evergreen species, were also significantly, positively correlated with Pr. We suggest that this is due to higher rm decreasing diffusion of (photo) respiratory CO2 out of the leaf. Cell wall thickness had a positive effect on Pr and rm, while the fraction of intercellular airspace had no effect. Both were significantly different between evergreen conifers and other types. Our findings suggest that species with a higher rm use a greater fraction of mitochondria-derived CO2, especially when stomatal conductance is low. This should be taken into account when modeling the overall CO2 fertilization effect for terrestrial ecosystems dominated by high rm species.
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Affiliation(s)
| | - Helle Juel Martens
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Rolighedsvej 23, Frederiksberg C, 1958 Copenhagen, Denmark
| | - Lianhong Gu
- Climate Change Science Institute & Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6301, USA
| | - Anna Monrad Jensen
- Department of Forestry and Wood Technology, Linnaeus University, 351 95 Växjö, Sweden
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23
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Carriquí M, Nadal M, Flexas J. Acclimation of mesophyll conductance and anatomy to light during leaf aging in Arabidopsis thaliana. PHYSIOLOGIA PLANTARUM 2021; 172:1894-1907. [PMID: 33724455 DOI: 10.1111/ppl.13398] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 03/04/2021] [Accepted: 03/10/2021] [Indexed: 06/12/2023]
Abstract
Mesophyll conductance (gm ), a key limitation to photosynthesis, is strongly driven by leaf anatomy, which is in turn influenced by environmental growth conditions and ontogeny. However, studies examining the combined environment × age effect on both leaf anatomy and photosynthesis are scarce, and none have been carried out in short-lived plants. Here, we studied the variation of photosynthesis and leaf anatomy in the model species Arabidopsis thaliana (Col-0) grown under three different light intensities at two different leaf ages. We found that light × age interaction was significant for photosynthesis but not for anatomical characteristics. Increasing growth light intensities resulted in increases in leaf mass per area, thickness, number of palisade cell layers, and chloroplast area lining to intercellular airspace. Low and moderate-but not high-light intensity had a significant effect on all photosynthetic characteristics. Leaf aging was associated with increases in cell wall thickness (Tcw ) in all light treatments and in increases in leaf thickness in plants grown under low and moderate light intensities. However, gm did not vary with leaf aging, and photosynthesis only decreased with leaf age under moderate and high light, suggesting a compensatory effect between increased Tcw and decreased chloroplast thickness on the total CO2 diffusion resistance.
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Affiliation(s)
- Marc Carriquí
- School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia
- Research Group in Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears, Palma, Spain
| | - Miquel Nadal
- Research Group in Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears, Palma, Spain
| | - Jaume Flexas
- Research Group in Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears, Palma, Spain
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24
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Adnew GA, Hofmann MEG, Pons TL, Koren G, Ziegler M, Lourens LJ, Röckmann T. Leaf scale quantification of the effect of photosynthetic gas exchange on Δ 47 of CO 2. Sci Rep 2021; 11:14023. [PMID: 34234170 PMCID: PMC8263724 DOI: 10.1038/s41598-021-93092-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 06/15/2021] [Indexed: 11/30/2022] Open
Abstract
The clumped isotope composition (Δ47, the anomaly of the mass 47 isotopologue relative to the abundance expected from a random isotope distribution) of CO2 has been suggested as an additional tracer for gross CO2 fluxes. However, the effect of photosynthetic gas exchange on Δ47 has not been directly determined and two indirect/conceptual studies reported contradicting results. In this study, we quantify the effect of photosynthetic gas exchange on Δ47 of CO2 using leaf cuvette experiments with one C4 and two C3 plants. The experimental results are supported by calculations with a leaf cuvette model. Our results demonstrate the important roles of the Δ47 value of CO2 entering the leaf, kinetic fractionation as CO2 diffuses into, and out of the leaf and CO2–H2O isotope exchange with leaf water. We experimentally confirm the previously suggested dependence of Δ47 of CO2 in the air surrounding a leaf on the stomatal conductance and back-diffusion flux. Gas exchange can enrich or deplete the Δ47 of CO2 depending on the Δ47 of CO2 entering the leaf and the fraction of CO2 exchanged with leaf water and diffused back to the atmosphere, but under typical ambient conditions, it will lead to a decrease in Δ47.
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Affiliation(s)
- Getachew Agmuas Adnew
- Institute for Marine and Atmospheric Research Utrecht, Utrecht University, Utrecht, The Netherlands.
| | - Magdalena E G Hofmann
- Institute for Marine and Atmospheric Research Utrecht, Utrecht University, Utrecht, The Netherlands.,Picarro B.V., 's-Hertogenbosch, The Netherlands
| | - Thijs L Pons
- Institute of Environmental Biology, Utrecht University, Utrecht, The Netherlands
| | - Gerbrand Koren
- Meteorology and Air Quality Group, Wageningen University, Wageningen, The Netherlands
| | - Martin Ziegler
- Department of Earth Sciences, Utrecht University, Utrecht, The Netherlands
| | - Lucas J Lourens
- Department of Earth Sciences, Utrecht University, Utrecht, The Netherlands
| | - Thomas Röckmann
- Institute for Marine and Atmospheric Research Utrecht, Utrecht University, Utrecht, The Netherlands
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25
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Roig-Oliver M, Rayon C, Roulard R, Fournet F, Bota J, Flexas J. Reduced photosynthesis in Arabidopsis thaliana atpme17.2 and atpae11.1 mutants is associated to altered cell wall composition. PHYSIOLOGIA PLANTARUM 2021; 172:1439-1451. [PMID: 32770751 DOI: 10.1111/ppl.13186] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 07/31/2020] [Accepted: 08/06/2020] [Indexed: 05/06/2023]
Abstract
The cell wall is a complex and dynamic structure that determines plants' performance by constant remodeling of its compounds. Although cellulose is its major load-bearing component, pectins are crucial to determine wall characteristics. Changes in pectin physicochemical properties, due to pectin remodeling enzymes (PRE), induce the rearrangement of cell wall compounds, thus, modifying wall architecture. In this work, we tested for the first time how cell wall dynamics affect photosynthetic properties in Arabidopsis thaliana pectin methylesterase atpme17.2 and pectin acetylesterase atpae11.1 mutants in comparison to wild-type Col-0. Our results showed maintained PRE activities comparing mutants with wild-type and no significant differences in cellulose, but cell wall non-cellulosic neutral sugars contents changed. Particularly, the amount of galacturonic acid (GalA) - which represents to some extent the pectin cell wall proportion - was reduced in the two mutants. Additionally, physiological characterization revealed that mutants presented a decreased net CO2 assimilation (AN ) because of reductions in both stomatal (gs ) and mesophyll conductances (gm ). Thus, our results suggest that atpme17.2 and atpae11.1 cell wall modifications due to genetic alterations could play a significant role in determining photosynthesis.
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Affiliation(s)
- Margalida Roig-Oliver
- Research Group on Plant Biology under Mediterranean Conditions, Departament de Biologia, Universitat de les Illes Balears (UIB) - Agro-Environmental and Water Economics Institute (INAGEA), Palma, 07122, Spain
| | - Catherine Rayon
- EA 3900-BIOPI, Biologie des Plantes et Innovation, Université de Picardie Jules Verne, Amiens, 80039, France
| | - Romain Roulard
- EA 3900-BIOPI, Biologie des Plantes et Innovation, Université de Picardie Jules Verne, Amiens, 80039, France
| | - François Fournet
- EA 3900-BIOPI, Biologie des Plantes et Innovation, Université de Picardie Jules Verne, Amiens, 80039, France
| | - Josefina Bota
- Research Group on Plant Biology under Mediterranean Conditions, Departament de Biologia, Universitat de les Illes Balears (UIB) - Agro-Environmental and Water Economics Institute (INAGEA), Palma, 07122, Spain
| | - Jaume Flexas
- Research Group on Plant Biology under Mediterranean Conditions, Departament de Biologia, Universitat de les Illes Balears (UIB) - Agro-Environmental and Water Economics Institute (INAGEA), Palma, 07122, Spain
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26
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Flexas J, Clemente-Moreno MJ, Bota J, Brodribb TJ, Gago J, Mizokami Y, Nadal M, Perera-Castro AV, Roig-Oliver M, Sugiura D, Xiong D, Carriquí M. Cell wall thickness and composition are involved in photosynthetic limitation. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:3971-3986. [PMID: 33780533 DOI: 10.1093/jxb/erab144] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 03/25/2021] [Indexed: 06/12/2023]
Abstract
The key role of cell walls in setting mesophyll conductance to CO2 (gm) and, consequently, photosynthesis is reviewed. First, the theoretical properties of cell walls that can affect gm are presented. Then, we focus on cell wall thickness (Tcw) reviewing empirical evidence showing that Tcw varies strongly among species and phylogenetic groups in a way that correlates with gm and photosynthesis; that is, the thicker the mesophyll cell walls, the lower the gm and photosynthesis. Potential interplays of gm, Tcw, dehydration tolerance, and hydraulic properties of leaves are also discussed. Dynamic variations of Tcw in response to the environment and their implications in the regulation of photosynthesis are discussed, and recent evidence suggesting an influence of cell wall composition on gm is presented. We then propose a hypothetical mechanism for the influence of cell walls on photosynthesis, combining the effects of thickness and composition, particularly pectins. Finally, we discuss the prospects for using biotechnology for enhancing photosynthesis by altering cell wall-related genes.
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Affiliation(s)
- Jaume Flexas
- Research Group on Plant Biology under Mediterranean Conditions, Institut d'Investigacions Agroambientals i d'Economia de l'Aigua (INAGEA) - Universitat de les Illes Balears (UIB), Ctra Valldemossa Km 7.5., 07122, Palma, Illes Balears, Spain
| | - María J Clemente-Moreno
- Research Group on Plant Biology under Mediterranean Conditions, Institut d'Investigacions Agroambientals i d'Economia de l'Aigua (INAGEA) - Universitat de les Illes Balears (UIB), Ctra Valldemossa Km 7.5., 07122, Palma, Illes Balears, Spain
| | - Josefina Bota
- Research Group on Plant Biology under Mediterranean Conditions, Institut d'Investigacions Agroambientals i d'Economia de l'Aigua (INAGEA) - Universitat de les Illes Balears (UIB), Ctra Valldemossa Km 7.5., 07122, Palma, Illes Balears, Spain
| | - Tim J Brodribb
- School of Biological Sciences, University of Tasmania, Hobart, TAS, Australia
| | - Jorge Gago
- Research Group on Plant Biology under Mediterranean Conditions, Institut d'Investigacions Agroambientals i d'Economia de l'Aigua (INAGEA) - Universitat de les Illes Balears (UIB), Ctra Valldemossa Km 7.5., 07122, Palma, Illes Balears, Spain
| | - Yusuke Mizokami
- Laboratory of Applied Ecology, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji-shi, Tokyo, Japan
| | - Miquel Nadal
- Research Group on Plant Biology under Mediterranean Conditions, Institut d'Investigacions Agroambientals i d'Economia de l'Aigua (INAGEA) - Universitat de les Illes Balears (UIB), Ctra Valldemossa Km 7.5., 07122, Palma, Illes Balears, Spain
| | - Alicia V Perera-Castro
- Research Group on Plant Biology under Mediterranean Conditions, Institut d'Investigacions Agroambientals i d'Economia de l'Aigua (INAGEA) - Universitat de les Illes Balears (UIB), Ctra Valldemossa Km 7.5., 07122, Palma, Illes Balears, Spain
| | - Margalida Roig-Oliver
- Research Group on Plant Biology under Mediterranean Conditions, Institut d'Investigacions Agroambientals i d'Economia de l'Aigua (INAGEA) - Universitat de les Illes Balears (UIB), Ctra Valldemossa Km 7.5., 07122, Palma, Illes Balears, Spain
| | - Daisuke Sugiura
- Laboratory of Crop Science, Department of Plant Production Sciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, Japan
| | - 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, China
| | - Marc Carriquí
- School of Biological Sciences, University of Tasmania, Hobart, TAS, Australia
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27
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Mantuano D, Ornellas T, Aidar MPM, Mantovani A. Photosynthetic activity increases with leaf size and intercellular spaces in an allomorphic lianescent aroid Rhodospatha oblongata. FUNCTIONAL PLANT BIOLOGY : FPB 2021; 48:557-566. [PMID: 33556303 DOI: 10.1071/fp20215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 12/17/2020] [Indexed: 06/12/2023]
Abstract
This study aimed to investigate leaf anatomy, as well as photosynthetic gas exchange, that underlie the improvement in light foraging capacity, which appears to occur in aroid vines seeking light exposure. Three levels of plant height (soil level, 3 m and 6 m) were categorised for the aroid vine Rhodospatha oblongata Poepp. to represent the transition from ground to canopy. Compared with shaded leaves, leaves exposed to high light conditions were thicker, presenting a larger, spongy parenchyma characterised by a larger transversal area of intercellular spaces. In addition to the increase in maximum CO2 assimilation (Amax) and thicker and larger leaf lamina, we found an increased light saturation point, light compensation point and water use efficiency at 500 µmol PPFD. Nitrogen content per leaf dry mass remained constant across habitats, but Amax/N was 1.5-times greater in the canopy position than in the leaves at soil level, suggesting that CO2 gain did not rely on an N-related biochemical apparatus. The lower δ13C discrimination observed at high canopy leaves corroborated the higher photosynthesis. Altogether, these results suggest that the large and exposed aroid leaves maintained carbon gain coupled with light gain through investing in a more efficient proportion of intercellular spaces and photosynthetic cell surface, which likely allowed a less pronounced CO2 gradient in substomatal-intercellular space.
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Affiliation(s)
- Dulce Mantuano
- Laboratório de Ecofisiologia Vegetal, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho 373, Bloco A, sala A1-118, CCS, Cidade Universitária, 21941-590, Rio de Janeiro, RJ, Brazil; and Corresponding author.
| | - Thales Ornellas
- Escola Nacional de Botânica Tropical; Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Rua Pacheco Leão 915, Jardim Botânico, 22460-030, Rio de Janeiro, Brazil
| | - Marcos P M Aidar
- Centro de Pesquisas em Ecologia e Fisiologia, Núcleo de Pesquisa em Fisiologia e Bioquímica, Instituto de Botânica de São Paulo, São Paulo, SP, Brazil
| | - André Mantovani
- Laboratório de Botânica Estrutural, Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Rua Pacheco Leão 915, Jardim Botânico, 22460-030, Rio de Janeiro, Brazil
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Portillo-Estrada M, Okereke CN, Jiang Y, Talts E, Kaurilind E, Niinemets Ü. Wounding-Induced VOC Emissions in Five Tropical Agricultural Species. Molecules 2021; 26:molecules26092602. [PMID: 33946933 PMCID: PMC8125398 DOI: 10.3390/molecules26092602] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/23/2021] [Accepted: 04/26/2021] [Indexed: 11/23/2022] Open
Abstract
Leaf mechanical wounding triggers a rapid release—within minutes—of a blend of volatile organic compounds. A wounding-induced VOC blend is mainly composed of oxygenated ubiquitous stress volatiles such as methanol and volatile products of lipoxygenase (LOX) pathway (mainly C5 and C6 alcohols and aldehydes and their derivatives), but also includes multiple minor VOCs that collectively act as infochemicals, inducing defences in non-damaged plant leaves and neighbouring plants and attracting herbivore enemies. At present, the interspecific variability of the rate of induction and magnitude of wounding-induced emissions and the extent to which plant structural traits and physiological activity alter these emissions are poorly known. Particularly scarce is information on the induced emissions in tropical agricultural plant species, despite their economic importance and large area of cultivation at regional and global scales. We chose five tropical crops with varying photosynthetic activity and leaf structural characteristics—Abelmoschus esculentus, Amaranthus cruentus, Amaranthus hybridus, Solanum aethiopicum, and Telfairia occidentalis—to characterize the kinetics and magnitude of wounding-induced emissions, hypothesizing that the induced emission response is greater and faster in physiologically more active species with greater photosynthetic activity than in less active species. Rapid highly repeatable leaf wounds (12 mm cuts) were generated by a within-leaf-chamber cutting knife. Wounding-induced VOC emissions were measured continuously with a proton-transfer reaction time-of-flight mass spectrometer and gas-chromatography mass spectrometry was used to separate isomers. Twenty-three ion VOCs and twelve terpenoid molecule structures were identified, whereas ubiquitous stress volatiles methanol (on average 40% of total emissions), hexenal (24%), and acetaldehyde (11%) were the main compounds across the species. Emissions of low-weight oxygenated compounds (LOC, 70% of total) and LOX products (29%) were positively correlated across species, but minor VOC components, monoterpenoids and benzenoids, were negatively correlated with LOC and LOX, indicating a reverse relationship between signal specificity and strength. There was a large interspecific variability in the rate of induction and emission magnitude, but the hypothesis of a stronger emission response in physiologically more active species was only partly supported. In addition, the overall emission levels were somewhat lower with different emission blend compared to the data reported for wild species, as well as different shares for the VOCs in the blend. The study demonstrates that wounding-dependent emissions from tropical agricultural crops can significantly contribute to atmospheric volatiles, and these emissions cannot be predicted based on current evidence of wild plant model systems.
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Affiliation(s)
- Miguel Portillo-Estrada
- Research Group Pleco (Plants and Ecosystems), Department of Biology, University of Antwerp, 2610 Wilrijk, Belgium
- Correspondence: ; Tel.: +32-3-265-1731
| | - Chikodinaka N. Okereke
- Chair of Crop Science and Plant Biology, Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 1, 51006 Tartu, Estonia; (C.N.O.); (E.T.); (E.K.); (Ü.N.)
| | - Yifan Jiang
- College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China;
| | - Eero Talts
- Chair of Crop Science and Plant Biology, Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 1, 51006 Tartu, Estonia; (C.N.O.); (E.T.); (E.K.); (Ü.N.)
| | - Eve Kaurilind
- Chair of Crop Science and Plant Biology, Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 1, 51006 Tartu, Estonia; (C.N.O.); (E.T.); (E.K.); (Ü.N.)
| | - Ülo Niinemets
- Chair of Crop Science and Plant Biology, Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 1, 51006 Tartu, Estonia; (C.N.O.); (E.T.); (E.K.); (Ü.N.)
- Estonian Academy of Sciences, Kohtu 6, 10130 Tallinn, Estonia
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29
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Nadal M, Perera-Castro AV, Gulías J, Farrant JM, Flexas J. Resurrection plants optimize photosynthesis despite very thick cell walls by means of chloroplast distribution. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:2600-2610. [PMID: 33483750 DOI: 10.1093/jxb/erab022] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 01/18/2021] [Indexed: 06/12/2023]
Abstract
Resurrection plants are vascular species able to sustain extreme desiccation in their vegetative tissues. Despite its potential interest, the role of leaf anatomy in CO2 diffusion and photosynthesis under non-stressed conditions has not been explored in these species. Net CO2 assimilation (An) and its underlying diffusive, biochemical, and anatomical determinants were assessed in 10 resurrection species from diverse locations, including ferns, and homoiochlorophyllous and poikilochlorophyllous angiosperms. Data obtained were compared with previously published results in desiccation-sensitive ferns and angiosperms. An in resurrection plants was mostly driven by mesophyll conductance to CO2 (gm) and limited by CO2 diffusion. Resurrection species had a greater cell wall thickness (Tcw) than desiccation-sensitive plants, a feature associated with limited CO2 diffusion in the mesophyll, but also greater chloroplast exposure to intercellular spaces (Sc), which usually leads to higher gm. This combination enabled a higher An per Tcw compared with desiccation-sensitive species. Resurrection species possess unusual anatomical features that could confer stress tolerance (thick cell walls) without compromising the photosynthetic capacity (high chloroplast exposure). This mechanism is particularly successful in resurrection ferns, which display higher photosynthesis than their desiccation-sensitive counterparts.
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Affiliation(s)
- Miquel Nadal
- Research Group on Plant Biology under Mediterranean Conditions, Departament de Biologia, Universitat de les Illes Balears (UIB), INAGEA, Carretera de Valldemossa Km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain
| | - Alicia V Perera-Castro
- Research Group on Plant Biology under Mediterranean Conditions, Departament de Biologia, Universitat de les Illes Balears (UIB), INAGEA, Carretera de Valldemossa Km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain
| | - Javier Gulías
- Research Group on Plant Biology under Mediterranean Conditions, Departament de Biologia, Universitat de les Illes Balears (UIB), INAGEA, Carretera de Valldemossa Km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain
| | - Jill M Farrant
- Department of Molecular and Cell Biology, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa
| | - Jaume Flexas
- Research Group on Plant Biology under Mediterranean Conditions, Departament de Biologia, Universitat de les Illes Balears (UIB), INAGEA, Carretera de Valldemossa Km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain
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Abstract
Since 1893, when the word "photosynthesis" was first coined by Charles Reid Barnes and Conway MacMillan, our understanding of the elements and regulation of this complex process is far from being entirely understood. We aim to review the most relevant advances in photosynthesis research from the last few years and to provide a perspective on the forthcoming research in this field. Recent discoveries related to light sensing, harvesting, and dissipation; kinetics of CO2 fixation; components and regulators of CO2 diffusion through stomata and mesophyll; and genetic engineering for improving photosynthetic and production capacities of crops are addressed.
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Affiliation(s)
- Alicia V Perera-Castro
- Department of Biology, Universitat de les Illes Balears, INAGEA, Palma de Mallorca, Spain
| | - Jaume Flexas
- Department of Biology, Universitat de les Illes Balears, INAGEA, Palma de Mallorca, Spain
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31
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Gimeno TE, Campany CE, Drake JE, Barton CVM, Tjoelker MG, Ubierna N, Marshall JD. Whole-tree mesophyll conductance reconciles isotopic and gas-exchange estimates of water-use efficiency. THE NEW PHYTOLOGIST 2021; 229:2535-2547. [PMID: 33217000 DOI: 10.1111/nph.17088] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Accepted: 11/07/2020] [Indexed: 06/11/2023]
Abstract
Photosynthetic water-use efficiency (WUE) describes the link between terrestrial carbon (C) and water cycles. Estimates of intrinsic WUE (iWUE) from gas exchange and C isotopic composition (δ13 C) differ due to an internal conductance in the leaf mesophyll (gm ) that is variable and seldom computed. We present the first direct estimates of whole-tree gm , together with iWUE from whole-tree gas exchange and δ13 C of the phloem (δ13 Cph ). We measured gas exchange, online 13 C-discrimination, and δ13 Cph monthly throughout spring, summer, and autumn in Eucalyptus tereticornis grown in large whole-tree chambers. Six trees were grown at ambient temperatures and six at a 3°C warmer air temperature; a late-summer drought was also imposed. Drought reduced whole-tree gm . Warming had few direct effects, but amplified drought-induced reductions in whole-tree gm . Whole-tree gm was similar to leaf gm for these same trees. iWUE estimates from δ13 Cph agreed with iWUE from gas exchange, but only after incorporating gm . δ13 Cph was also correlated with whole-tree 13 C-discrimination, but offset by -2.5 ± 0.7‰, presumably due to post-photosynthetic fractionations. We conclude that δ13 Cph is a good proxy for whole-tree iWUE, with the caveats that post-photosynthetic fractionations and intrinsic variability of gm should be incorporated to provide reliable estimates of this trait in response to abiotic stress.
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Affiliation(s)
- Teresa E Gimeno
- Basque Centre for Climate Change (BC3), Leioa, 48940, Spain
- IKERBASQUE, Basque Foundation for Science, Bilbao, 48008, Spain
| | - Courtney E Campany
- Department of Biology, Shepherd University, Shepherdstown, WV, 25443, USA
| | - John E Drake
- Forest and Natural Resources Management, SUNY-ESF, Syracuse, NY, 132110, USA
| | - Craig V M Barton
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, 2751, Australia
| | - Mark G Tjoelker
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, 2751, Australia
| | - Nerea Ubierna
- Research School of Biology, The Australian National University, Acton, ACT, 2601, Australia
| | - John D Marshall
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Skogsmarksgränd 17, 907 36, Umeå, Sweden
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32
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Ferroni L, Brestič M, Živčak M, Cantelli R, Pancaldi S. Increased photosynthesis from a deep-shade to high-light regime occurs by enhanced CO 2 diffusion into the leaf of Selaginella martensii. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2021; 160:143-154. [PMID: 33486204 DOI: 10.1016/j.plaphy.2021.01.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 01/11/2021] [Indexed: 06/12/2023]
Abstract
The current understanding of photosynthesis across land plant phylogeny strongly indicates that ancient vascular plants are mainly limited by strong constitutive CO2 diffusional constraints, particularly low stomatal and mesophyll conductance. Considering that the lycophyte Selaginella martensii can demonstrate long-term light acclimation, this study addresses the regulation extent of CO2 assimilation in this species cultivated under contrasting light regimes of deep shade, medium shade and high light. Comparative analyses of photosynthetic traits, CO2 conductance and leaf morpho-anatomy revealed acclimation plasticity similar to that of seed plants, though occurring in the context of an inherently low photosynthetic capacity typical of lycophytes. Specific modulations of the stomatal density and aperture, chloroplast surface exposed to mesophyll airspaces and cell wall thickness sustained a marked improvement in CO2 diffusion from deep shade to high light. However, the maximum carboxylation rate was comparatively less effectively upregulated, leading to a greater incidence of biochemical limitations of photosynthesis. Because of a low carboxylation capacity under any light regime, a lycophyte prevents potential photodamage to the chloroplast by not only exploiting the thermal dissipation of excess absorbed energy but also diverting a large fraction of photosynthetic electrons to sinks alternative to carboxylation.
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Affiliation(s)
- Lorenzo Ferroni
- Department of Life Sciences and Biotechnology, University of Ferrara, Corso Ercole I d'Este 32, 44121, Ferrara, Italy; Department of Plant Physiology, Slovak University of Agriculture, Tr. A. Hlinku 2, 949 01, Nitra, Slovakia.
| | - Marián Brestič
- Department of Plant Physiology, Slovak University of Agriculture, Tr. A. Hlinku 2, 949 01, Nitra, Slovakia.
| | - Marek Živčak
- Department of Plant Physiology, Slovak University of Agriculture, Tr. A. Hlinku 2, 949 01, Nitra, Slovakia
| | - Riccardo Cantelli
- Department of Life Sciences and Biotechnology, University of Ferrara, Corso Ercole I d'Este 32, 44121, Ferrara, Italy
| | - Simonetta Pancaldi
- Department of Life Sciences and Biotechnology, University of Ferrara, Corso Ercole I d'Este 32, 44121, Ferrara, Italy
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Schiestl‐Aalto P, Stangl ZR, Tarvainen L, Wallin G, Marshall J, Mäkelä A. Linking canopy-scale mesophyll conductance and phloem sugar δ 13 C using empirical and modelling approaches. THE NEW PHYTOLOGIST 2021; 229:3141-3155. [PMID: 33222199 PMCID: PMC7986199 DOI: 10.1111/nph.17094] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 11/16/2020] [Indexed: 05/26/2023]
Abstract
Interpreting phloem carbohydrate or xylem tissue carbon isotopic composition as measures of water-use efficiency or past tree productivity requires in-depth knowledge of the factors altering the isotopic composition within the pathway from ambient air to phloem contents and tree ring. One of least understood of these factors is mesophyll conductance (gm ). We formulated a dynamic model describing the leaf photosynthetic pathway including seven alternative gm descriptions and a simple transport of sugars from foliage down the trunk. We parameterised the model for a boreal Scots pine stand and compared simulated gm responses with weather variations. We further compared the simulated δ13 C of new photosynthates among the different gm descriptions and against measured phloem sugar δ13 C. Simulated gm estimates of the seven descriptions varied according to weather conditions, resulting in varying estimates of phloem δ13 C during cold/moist and warm/dry periods. The model succeeded in predicting a drought response and a postdrought release in phloem sugar δ13 C indicating suitability of the model for inverse prediction of leaf processes from phloem isotopic composition. We suggest short-interval phloem sampling during and after extreme weather conditions to distinguish between mesophyll conductance drivers for future model development.
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Affiliation(s)
- Pauliina Schiestl‐Aalto
- Institute for Atmospheric and Earth System Research (INAR)/Forest SciencesHelsinki00014Finland
- Department of Forest Ecology and ManagementSLUUmeå901 83Sweden
| | | | - Lasse Tarvainen
- Department of Biological and Environmental SciencesUniversity of GothenburgGothenburg405 30Sweden
| | - Göran Wallin
- Department of Biological and Environmental SciencesUniversity of GothenburgGothenburg405 30Sweden
| | - John Marshall
- Department of Forest Ecology and ManagementSLUUmeå901 83Sweden
| | - Annikki Mäkelä
- Institute for Atmospheric and Earth System Research (INAR)/Forest SciencesHelsinki00014Finland
- Department of Forest Ecology and ManagementSLUUmeå901 83Sweden
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34
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Westbrook AS, McAdam SAM. Stomatal density and mechanics are critical for high productivity: insights from amphibious ferns. THE NEW PHYTOLOGIST 2021; 229:877-889. [PMID: 32761918 DOI: 10.1111/nph.16850] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 07/28/2020] [Indexed: 06/11/2023]
Abstract
Angiosperm dominance in terrestrial landscapes is partially attributable to high photosynthetic capacities. Angiosperms benefit from diverse anatomical and physiological adaptations, making it difficult to determine which factors may have been prerequisites for the evolution of enhanced photosynthetic rates in this group. We employed a novel approach to this problem: comparisons between angiosperms and Marsileaceae, a family of semi-aquatic ferns that are among the only land plants to match angiosperm photosynthetic rates. We found that Marsileaceae have very high stomatal densities and, like angiosperms but unlike all other ferns previously studied, exhibit wrong-way stomatal responses to excision. These results suggest that stomatal density and a little-studied angiosperm trait, the capacity for lateral displacement of guard cells into neighboring epidermal cells, are crucial for facilitating high rates of gas exchange. Our analysis also associates these adaptations in Marsileaceae with an increased risk of excessive water loss during drought. Our findings indicate that evolution in stomatal physiology was a prerequisite for high photosynthetic capacities in vascular plants and a key driver of the abrupt Cretaceous rise of the angiosperms.
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Affiliation(s)
- Anna S Westbrook
- Department of Botany and Plant Pathology, Purdue Center for Plant Biology, Purdue University, West Lafayette, IN, 47907, USA
| | - Scott A M McAdam
- Department of Botany and Plant Pathology, Purdue Center for Plant Biology, Purdue University, West Lafayette, IN, 47907, USA
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35
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Roig-Oliver M, Bresta P, Nadal M, Liakopoulos G, Nikolopoulos D, Karabourniotis G, Bota J, Flexas J. Cell wall composition and thickness affect mesophyll conductance to CO2 diffusion in Helianthus annuus under water deprivation. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:7198-7209. [PMID: 32905592 DOI: 10.1093/jxb/eraa413] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Accepted: 09/06/2020] [Indexed: 06/11/2023]
Abstract
Water deprivation affects photosynthesis, leaf anatomy, and cell wall composition. Although the former effects have been widely studied, little is known regarding those changes in cell wall major (cellulose, hemicelluloses, pectin, and lignin) and minor (cell wall-bound phenolics) compounds in plants acclimated to short- and long-term water deprivation and during recovery. In particular, how these cell wall changes impact anatomy and/or photosynthesis, specifically mesophyll conductance to CO2 diffusion (gm), has been scarcely studied. To induce changes in photosynthesis, cell wall composition and anatomy, Helianthus annuus plants were studied under five conditions: (i) control (i.e. without stress) (CL); (ii) long-term water deficit stress (LT); (iii) long-term water deficit stress with recovery (LT-Rec); (iv) short-term water deficit stress (ST); and (v) short-term water deficit stress with recovery (ST-Rec), resulting in a wide photosynthetic range (from 3.80 ± 1.05 μmol CO2 m-2 s-1 to 24.53 ± 0.42 μmol CO2 m-2 s-1). Short- and long-term water deprivation and recovery induced distinctive responses of the examined traits, evidencing a cell wall dynamic turnover during plants acclimation to each condition. In particular, we demonstrated for the first time how gm correlated negatively with lignin and cell wall-bound phenolics and how the (cellulose+hemicelloses)/pectin ratio was linked to cell wall thickness (Tcw) variations.
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Affiliation(s)
- Margalida Roig-Oliver
- Research Group on Plant Biology under Mediterranean Conditions, Departament de Biologia, Universitat de les Illes Balears (UIB), INAGEA, Carretera de Valldemossa Km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain
| | - Panagiota Bresta
- Laboratory of Plant Physiology and Morphology, Department of Crop Science, Agricultural University of Athens (AUA), Iera Odos 75, Botanikos, Athens, Greece
| | - Miquel Nadal
- Research Group on Plant Biology under Mediterranean Conditions, Departament de Biologia, Universitat de les Illes Balears (UIB), INAGEA, Carretera de Valldemossa Km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain
| | - Georgios Liakopoulos
- Laboratory of Plant Physiology and Morphology, Department of Crop Science, Agricultural University of Athens (AUA), Iera Odos 75, Botanikos, Athens, Greece
| | - Dimosthenis Nikolopoulos
- Laboratory of Plant Physiology and Morphology, Department of Crop Science, Agricultural University of Athens (AUA), Iera Odos 75, Botanikos, Athens, Greece
| | - George Karabourniotis
- Laboratory of Plant Physiology and Morphology, Department of Crop Science, Agricultural University of Athens (AUA), Iera Odos 75, Botanikos, Athens, Greece
| | - Josefina Bota
- Research Group on Plant Biology under Mediterranean Conditions, Departament de Biologia, Universitat de les Illes Balears (UIB), INAGEA, Carretera de Valldemossa Km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain
| | - Jaume Flexas
- Research Group on Plant Biology under Mediterranean Conditions, Departament de Biologia, Universitat de les Illes Balears (UIB), INAGEA, Carretera de Valldemossa Km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain
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36
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Gao L, Lu Z, Ding L, Xie K, Wang M, Ling N, Guo S. Anatomically induced changes in rice leaf mesophyll conductance explain the variation in photosynthetic nitrogen use efficiency under contrasting nitrogen supply. BMC PLANT BIOLOGY 2020; 20:527. [PMID: 33208102 PMCID: PMC7672947 DOI: 10.1186/s12870-020-02731-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 11/05/2020] [Indexed: 05/06/2023]
Abstract
BACKGROUND The ratio of CO2 mesophyll conductance (gm) to Ribulose-1, 5-bisphosphate carboxylase/oxygenase (Rubisco) content has been suggested to positively affect photosynthetic nitrogen use efficiency (PNUE). The anatomical basis of gm has been quantified, but information on the relationship between cell-level anatomies and PNUE is less advanced. Here, hydroponic experiments were conducted in rice plants supplied with ammonium (NH4+) and nitrate (NO3-) under three N levels (low, 0.71 mM; intermediate, 2.86 mM; high, 7.14 mM) to investigate the gas exchange parameters, leaf anatomical structure and PNUE. RESULTS The results showed a lower PNUE in plants supplied with high nitrogen and NH4+, which was positively correlated with the gm/Rubisco ratio. A one-dimensional within-leaf model revealed that the resistance to CO2 diffusion in the liquid phase (rliq) dominated the overall mesophyll resistance (rm), in which CO2 transfer resistance in the cell wall, cytoplasm and stroma were significantly affected by nitrogen supply. The chloroplast surface area exposed to intercellular space (Sc) per Rubisco rather than the gm/Sc ratio was positively correlated with PNUE and was thus considered a key component influencing PNUE. CONCLUSION In conclusion, our study emphasized that Sc was the most important anatomical trait in coordinating gm and PNUE with contrasting N supply.
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Affiliation(s)
- Limin Gao
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Weigang 1, Nanjing, 210095, China
| | - Zhifeng Lu
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Weigang 1, Nanjing, 210095, China
| | - Lei Ding
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Weigang 1, Nanjing, 210095, China
| | - Kailiu Xie
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Weigang 1, Nanjing, 210095, China
| | - Min Wang
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Weigang 1, Nanjing, 210095, China
| | - Ning Ling
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Weigang 1, Nanjing, 210095, China
| | - Shiwei Guo
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Weigang 1, Nanjing, 210095, China.
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37
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Perera-Castro AV, Nadal M, Flexas J. What drives photosynthesis during desiccation? Mosses and other outliers from the photosynthesis-elasticity trade-off. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:6460-6470. [PMID: 32686831 DOI: 10.1093/jxb/eraa328] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 07/15/2020] [Indexed: 06/11/2023]
Abstract
In vascular plants, more rigid leaves have been linked to lower photosynthetic capacity, associated with low CO2 diffusion across the mesophyll, indirectly resulting in a trade-off between photosynthetic capacity (An) and bulk modulus of elasticity (ε). However, we evaluated mosses, liverworts, and Chara sp., plus some lycophytes and ferns, and found that they behaved as clear outliers of the An-ε relationship. Despite this finding, when vascular and non-vascular plants were plotted together, ε still linearly determined the cessation of net photosynthesis during desiccation both in species with stomata (either actively or hydro-passively regulated) and in species lacking stomata, and regardless of their leaf structure. The latter result challenges our current view of photosynthetic responses to desiccation and/or water stress. Structural features and hydric strategy are discussed as possible explanations for the deviation of these species from the An-ε trade-off, as well as for the general linear dependency between ε and the full cessation of An during desiccation.
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Affiliation(s)
- Alicia V Perera-Castro
- Research Group on Plant Biology under Mediterranean Conditions. Departament de Biologia, Universitat de les Illes Balears, INAGEA Carretera de Valldemossa Km 7.5, Palma de Mallorca, Illes Balears, Spain
| | - Miquel Nadal
- Research Group on Plant Biology under Mediterranean Conditions. Departament de Biologia, Universitat de les Illes Balears, INAGEA Carretera de Valldemossa Km 7.5, Palma de Mallorca, Illes Balears, Spain
| | - Jaume Flexas
- Research Group on Plant Biology under Mediterranean Conditions. Departament de Biologia, Universitat de les Illes Balears, INAGEA Carretera de Valldemossa Km 7.5, Palma de Mallorca, Illes Balears, Spain
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38
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Crous KY, Campany C, Lopez R, Cano FJ, Ellsworth DS. Canopy position affects photosynthesis and anatomy in mature Eucalyptus trees in elevated CO2. TREE PHYSIOLOGY 2020; 41:tpaa117. [PMID: 32918811 DOI: 10.1093/treephys/tpaa117] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 08/26/2020] [Accepted: 09/10/2020] [Indexed: 06/11/2023]
Abstract
Leaves are exposed to different light conditions according to their canopy position, resulting in structural and anatomical differences with consequences for carbon uptake. While these structure-function relationships have been thoroughly explored in dense forest canopies, such gradients may be diminished in open canopies, and they are often ignored in ecosystem models. We tested within-canopy differences in photosynthetic properties and structural traits in leaves in a mature Eucalyptus tereticornis canopy exposed to long-term elevated CO2 for up to three years. We explored these traits in relation to anatomical variation and diffusive processes for CO2 (i.e., stomatal conductance, gs and mesophyll conductance, gm) in both upper and lower portions of the canopy receiving ambient and elevated CO2. While shade resulted in 13% lower leaf mass per area ratio (MA) in lower versus upper canopy leaves, there was no relationship between leaf Nmass and canopy gap fraction. Both maximum carboxylation capacity (Vcmax) and maximum electron transport (Jmax) were ~ 18% lower in shaded leaves and were also reduced by ~ 22% with leaf aging. In mature leaves, we found no canopy differences for gm or gs, despite anatomical differences in MA, leaf thickness and mean mesophyll thickness between canopy positions. There was a positive relationship between net photosynthesis and gm or gs in mature leaves. Mesophyll conductance was negatively correlated with mean parenchyma length, suggesting that long palisade cells may contribute to a longer CO2 diffusional pathway and more resistance to CO2 transfer to chloroplasts. Few other relationships between gm and anatomical variables were found in mature leaves, which may be due to the open crown of Eucalyptus. Consideration of shade effects and leaf-age dependent responses to photosynthetic capacity and mesophyll conductance are critical to improve canopy photosynthesis models and will improve understanding of long-term responses to elevated CO2 in tree canopies.
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Affiliation(s)
- K Y Crous
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW 2751, Australia
| | - C Campany
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW 2751, Australia
- Department of Biology, Shepherd University, P.O. Box 5000, Shepherdstown, West Virginia, 25443, USA
| | - R Lopez
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW 2751, Australia
- Departamento de Sistemas y Recursos Naturales, Universidad Politécnica de Madrid, 28040 Madrid, Spain
| | - F J Cano
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW 2751, Australia
- ARC Centre of Excellence for Translational Photosynthesis, Western Sydney University, Locked Bag 1797, Penrith NSW 2751, Australia
| | - D S Ellsworth
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW 2751, Australia
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Veromann-Jürgenson LL, Brodribb TJ, Niinemets Ü, Tosens T. Variability in the chloroplast area lining the intercellular airspace and cell walls drives mesophyll conductance in gymnosperms. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:4958-4971. [PMID: 32392579 DOI: 10.1093/jxb/eraa231] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 05/05/2020] [Indexed: 06/11/2023]
Abstract
The photosynthetic efficiency of plants in different environments is controlled by stomata, hydraulics, biochemistry, and mesophyll conductance (gm). Recently, gm was demonstrated to be the key limitation of photosynthesis in gymnosperms. Values of gm across gymnosperms varied over 20-fold, but this variation was poorly explained by robust structure-bound integrated traits such as leaf dry mass per area. Understanding how the component structural traits control gm is central for identifying the determinants of variability in gm across plant functional and phylogenetic groups. Here, we investigated the structural traits responsible for gm in 65 diverse gymnosperms. Although the integrated morphological traits, shape, and anatomical characteristics varied widely across species, the distinguishing features of all gymnosperms were thick mesophyll cell walls and low chloroplast area exposed to intercellular airspace (Sc/S) compared with angiosperms. Sc/S and cell wall thickness were the fundamental traits driving variations in gm across gymnosperm species. Chloroplast thickness was the strongest limitation of gm among liquid-phase components. The variation in leaf dry mass per area was not correlated with the key ultrastructural traits determining gm. Thus, given the absence of correlating integrated easy-to-measure traits, detailed knowledge of underlying component traits controlling gm across plant taxa is necessary to understand the photosynthetic limitations across ecosystems.
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Affiliation(s)
| | - Timothy J Brodribb
- School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia
| | - Ülo Niinemets
- Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Tartu, Estonia
- Estonian Academy of Sciences, Tallinn, Estonia
| | - Tiina Tosens
- Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Tartu, Estonia
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40
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Carriquí M, Nadal M, Clemente-Moreno MJ, Gago J, Miedes E, Flexas J. Cell wall composition strongly influences mesophyll conductance in gymnosperms. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 103:1372-1385. [PMID: 32390169 DOI: 10.1111/tpj.14806] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 04/22/2020] [Accepted: 04/28/2020] [Indexed: 06/11/2023]
Abstract
Cell wall thickness is widely recognized as one of the main determinants of mesophyll conductance to CO2 (gm ). However, little is known about the components that regulate effective CO2 diffusivity in the cell wall (i.e. the ratio between actual porosity and tortuosity, the other two biophysical diffusion properties of cell walls). The aim of this study was to assess, at the interspecific level, potential relationships between cell wall composition, cell wall thickness (Tcw ) and gm . Gymnosperms constitute an ideal group to deepen these relationships, as they present, on average, the thickest cell walls within spermatophytes. We characterized the foliar gas exchange, the morphoanatomical traits related with gm , the leaf fraction constituted by cell walls and three main components of primary cell walls (hemicelluloses, cellulose and pectins) in seven gymnosperm species. We found that, although the relatively low gm of gymnosperms was mainly determined by their elevated Tcw , gm was also strongly correlated with cell wall composition, which presumably sets the final effective CO2 diffusivity. The data presented here suggest that (i) differences in gm are strongly correlated to the pectins to hemicelluloses and cellulose ratio in gymnosperms, and (ii) variations in cell wall composition may modify effective CO2 diffusivity in the cell wall to compensate the negative impact of thickened walls. We speculate that higher relative pectin content allows higher gm because pectins increase cell wall hydrophilicity and CO2 molecules cross the wall dissolved in water.
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Affiliation(s)
- Marc Carriquí
- Research Group in Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears (UIB) - Agro-Environmental and Water Economics Institute (INAGEA), Palma, Illes Balears, 07122, Spain
- School of Natural Sciences, University of Tasmania (UTAS), Bag 55, Hobart, Tasmania, 7001, Australia
| | - Miquel Nadal
- Research Group in Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears (UIB) - Agro-Environmental and Water Economics Institute (INAGEA), Palma, Illes Balears, 07122, Spain
| | - María J Clemente-Moreno
- Research Group in Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears (UIB) - Agro-Environmental and Water Economics Institute (INAGEA), Palma, Illes Balears, 07122, Spain
| | - Jorge Gago
- Research Group in Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears (UIB) - Agro-Environmental and Water Economics Institute (INAGEA), Palma, Illes Balears, 07122, Spain
| | - Eva Miedes
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Montegancedo UPM, Pozuelo de Alarcón, Madrid, 28223, Spain
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Madrid, 28040, Spain
| | - Jaume Flexas
- Research Group in Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears (UIB) - Agro-Environmental and Water Economics Institute (INAGEA), Palma, Illes Balears, 07122, Spain
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Sugiura D, Terashima I, Evans JR. A Decrease in Mesophyll Conductance by Cell-Wall Thickening Contributes to Photosynthetic Downregulation. PLANT PHYSIOLOGY 2020; 183:1600-1611. [PMID: 32518201 PMCID: PMC7401118 DOI: 10.1104/pp.20.00328] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 05/26/2020] [Indexed: 05/30/2023]
Abstract
It has been argued that accumulation of nonstructural carbohydrates triggers a decrease in Rubisco content, which downregulates photosynthesis. However, a decrease in the sink-source ratio in several plant species leads to a decrease in photosynthesis and increases in both structural and nonstructural carbohydrate content. Here, we tested whether increases in cell-wall materials, rather than starch content, impact directly on photosynthesis by decreasing mesophyll conductance. We measured various morphological, anatomical, and physiological traits in primary leaves of soybean (Glycine max) and French bean (Phaseolus vulgaris) grown under high- or low-nitrogen conditions. We removed other leaves 2 weeks after sowing to decrease the sink-source ratio and conducted measurements 0, 1, and 2 weeks after defoliation.
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Affiliation(s)
- Daisuke Sugiura
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - Ichiro Terashima
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - John R Evans
- Australian Research Council Centre of Excellence for Translational Photosynthesis, Research School of Biology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
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42
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Ye M, Zhang Z, Huang G, Xiong Z, Peng S, Li Y. High leaf mass per area Oryza genotypes invest more leaf mass to cell wall and show a low mesophyll conductance. AOB PLANTS 2020; 12:plaa028. [PMID: 32765824 PMCID: PMC7396964 DOI: 10.1093/aobpla/plaa028] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 06/12/2020] [Indexed: 05/20/2023]
Abstract
The intraspecific variations of leaf structure and anatomy in rice leaves and their impacts on gas diffusion are still unknown. Researches about the tradeoff between structural compositions and intracellular chemical components within rice leaves are still lacking. The objectives of the present study were to investigate the varietal differences in leaf structure and leaf chemical compositions, and the tradeoff between leaf structural tissues and intracellular chemical components in rice leaves. Leaf structure, leaf anatomy, leaf chemical composition concentrations and gas exchange parameters were measured on eight Oryza sativa L. genotypes to investigate the intraspecific variations in leaf structure and leaf anatomy and their impacts on gas exchange parameters, and to study the tradeoff between leaf structural compositions (cell wall compounds) and intracellular chemical components (non-structural carbohydrates, nitrogen, chlorophyll). Leaf thickness increased with leaf mass per area (LMA), while leaf density did not correlate with LMA. Mesophyll cell surface area exposed to intercellular airspace (IAS) per leaf area, the surface area of chloroplasts exposed to IAS and cell wall thickness increased with LMA. Cell wall compounds accounted for 71.5 % of leaf dry mass, while mass-based nitrogen and chlorophyll concentrations decreased with LMA. Mesophyll conductance was negatively correlated with LMA and cell wall thickness. High LMA rice genotypes invest more leaf mass to cell wall and possess a low mesophyll conductance.
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Affiliation(s)
- Miao Ye
- Ministry of Agriculture 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, China
| | - Zhengcan Zhang
- Ministry of Agriculture 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, China
| | - Guanjun Huang
- Ministry of Agriculture 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, China
| | - Zhuang Xiong
- Ministry of Agriculture 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, China
| | - Shaobing Peng
- Ministry of Agriculture 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, China
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Yong Li
- Ministry of Agriculture 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, China
- Corresponding author’s e-mail address:
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43
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Mesophyll conductance: the leaf corridors for photosynthesis. Biochem Soc Trans 2020; 48:429-439. [DOI: 10.1042/bst20190312] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 01/25/2020] [Accepted: 01/30/2020] [Indexed: 12/15/2022]
Abstract
Besides stomata, the photosynthetic CO2 pathway also involves the transport of CO2 from the sub-stomatal air spaces inside to the carboxylation sites in the chloroplast stroma, where Rubisco is located. This pathway is far to be a simple and direct way, formed by series of consecutive barriers that the CO2 should cross to be finally assimilated in photosynthesis, known as the mesophyll conductance (gm). Therefore, the gm reflects the pathway through different air, water and biophysical barriers within the leaf tissues and cell structures. Currently, it is known that gm can impose the same level of limitation (or even higher depending of the conditions) to photosynthesis than the wider known stomata or biochemistry. In this mini-review, we are focused on each of the gm determinants to summarize the current knowledge on the mechanisms driving gm from anatomical to metabolic and biochemical perspectives. Special attention deserve the latest studies demonstrating the importance of the molecular mechanisms driving anatomical traits as cell wall and the chloroplast surface exposed to the mesophyll airspaces (Sc/S) that significantly constrain gm. However, even considering these recent discoveries, still is poorly understood the mechanisms about signaling pathways linking the environment a/biotic stressors with gm responses. Thus, considering the main role of gm as a major driver of the CO2 availability at the carboxylation sites, future studies into these aspects will help us to understand photosynthesis responses in a global change framework.
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44
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Miyazawa SI, Tobita H, Ujino-Ihara T, Suzuki Y. Oxygen response of leaf CO 2 compensation points used to determine Rubisco specificity factors of gymnosperm species. JOURNAL OF PLANT RESEARCH 2020; 133:205-215. [PMID: 32048093 DOI: 10.1007/s10265-020-01169-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Accepted: 01/22/2020] [Indexed: 06/10/2023]
Abstract
Rubisco specificity factor (Sc/o), a measure of the relative capacities of an enzyme to catalyze carboxylation and oxygenation of ribulose-1,5-bisphosphate, determines the extent of photosynthetic CO2 assimilation and photorespiratory CO2 release. The current model of C3 photosynthesis, the Farquhar-von Caemmerer-Berry (FvCB) model, requires a species-specific Sc/o. However, Sc/o values have never been reported in conifers, likely because in vitro kinetic analysis of conifer Rubisco presents difficulties. To estimate the Sc/o of conifers and compare it with angiosperm Sc/o, we measured changes in leaf CO2 compensation points (Γ) in response to O2 partial pressure for a variety of leaves, with different rates of day respiration (Rday) and maximum Rubisco carboxylation (Vcmax) in gymnosperms (Ginkgo biloba), conifers (Metasequoia glyptostroboides and Cryptomeria japonica), and angiosperms (Nicotiana tabacum and Phaseolus vulgaris). As predicted by the FvCB model, the slope of a linear function of Γ vs O2 partial pressure, d, increased alongside increasing Rday/Vcmax. The Sc/o was obtainable from this relationship between d and Rday/Vcmax, because the d values at Rday/Vcmax = 0 corresponded to α/Sc/o, where α was the photorespiratory CO2 release rate per Rubisco oxygenation rate (generally assumed to be 0.5). The calculated Sc/o values of N. tabacum and P. vulgaris exhibited good agreement with those reported by in vitro studies. The Sc/o values of both conifers were similar to those of the two angiosperm species. In contrast, the Sc/o value of G. biloba was significantly lower than those of the other four studied species. These results suggest that our new method for Sc/o estimation is applicable to C3 plants, including those for which in vitro kinetic analysis is difficult. Furthermore, results also suggest that conifer Sc/o does not differ significantly from that of C3 angiosperms, assuming α remains unchanged.
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Affiliation(s)
- Shin-Ichi Miyazawa
- Department of Forest Molecular Genetics and Biotechnology, Forestry and Forest Products Research Institute (FFPRI), 1 Matsunosato, Tsukuba, Ibaraki, 305-8687, Japan.
| | - Hiroyuki Tobita
- Department of Plant Ecology, FFPRI, 1 Matsunosato, Tsukuba, Ibaraki, 305-8687, Japan
| | - Tokuko Ujino-Ihara
- Department of Forest Molecular Genetics and Biotechnology, Forestry and Forest Products Research Institute (FFPRI), 1 Matsunosato, Tsukuba, Ibaraki, 305-8687, Japan
| | - Yuji Suzuki
- Faculty of Agriculture, Iwate University, 3-18-8 Ueda, Morioka, Iwate, 020-8550, Japan
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45
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Cousins AB, Mullendore DL, Sonawane BV. Recent developments in mesophyll conductance in C3, C4, and crassulacean acid metabolism plants. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:816-830. [PMID: 31960507 DOI: 10.1111/tpj.14664] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Accepted: 12/19/2019] [Indexed: 05/24/2023]
Abstract
The conductance of carbon dioxide (CO2 ) from the substomatal cavities to the initial sites of CO2 fixation (gm ) can significantly reduce the availability of CO2 for photosynthesis. There have been many recent reviews on: (i) the importance of gm for accurately modelling net rates of CO2 assimilation, (ii) on how leaf biochemical and anatomical factors influence gm , (iii) the technical limitation of estimating gm , which cannot be directly measured, and (iv) how gm responds to long- and short-term changes in growth and measurement environmental conditions. Therefore, this review will highlight these previous publications but will attempt not to repeat what has already been published. We will instead initially focus on the recent developments on the two-resistance model of gm that describe the potential of photorespiratory and respiratory CO2 released within the mitochondria to diffuse directly into both the chloroplast and the cytosol. Subsequently, we summarize recent developments in the three-dimensional (3-D) reaction-diffusion models and 3-D image analysis that are providing new insights into how the complex structure and organization of the leaf influences gm . Finally, because most of the reviews and literature on gm have traditionally focused on C3 plants we review in the final sections some of the recent developments, current understanding and measurement techniques of gm in C4 and crassulacean acid metabolism (CAM) plants. These plants have both specialized leaf anatomy and either a spatially or temporally separated CO2 concentrating mechanisms (C4 and CAM, respectively) that influence how we interpret and estimate gm compared with a C3 plants.
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Affiliation(s)
- Asaph B Cousins
- School of Biological Sciences, Washington State University, Pullman, WA, 99164, USA
| | - Daniel L Mullendore
- School of Biological Sciences, Washington State University, Pullman, WA, 99164, USA
| | - Balasaheb V Sonawane
- School of Biological Sciences, Washington State University, Pullman, WA, 99164, USA
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46
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Flexas J, Carriquí M. Photosynthesis and photosynthetic efficiencies along the terrestrial plant's phylogeny: lessons for improving crop photosynthesis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:964-978. [PMID: 31833133 DOI: 10.1111/tpj.14651] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 11/12/2019] [Accepted: 12/03/2019] [Indexed: 05/08/2023]
Abstract
Photosynthesis is the basis of all life on Earth. Surprisingly, until very recently, data on photosynthesis, photosynthetic efficiencies, and photosynthesis limitations in terrestrial land plants other than spermatophytes were very scarce. Here we provide an updated data compilation showing that maximum photosynthesis rates (expressed either on an area or dry mass basis) progressively scale along the land plant's phylogeny, from lowest values in bryophytes to largest in angiosperms. Unexpectedly, both photosynthetic water (WUE) and nitrogen (PNUE) use efficiencies also scale positively through the phylogeny, for which it has been commonly reported that these two efficiencies tend to trade-off between them when comparing different genotypes or a single species subject to different environmental conditions. After providing experimental evidence that these observed trends are mostly due to an increased mesophyll conductance to CO2 - associated with specific anatomical changes - along the phylogeny, we discuss how these findings on a large phylogenetic scale can provide useful information to address potential photosynthetic improvements in crops in the near future.
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Affiliation(s)
- Jaume Flexas
- Research Group on Plant Biology Under Mediterranean Conditions, Universitat de les Illes Balears - Instituto de Investigaciones Agroambientales y de Economía del Agua (UIB-INAGEA), Carretera de Valldemossa Km 7.5, 07122, Palma, Spain
| | - Marc Carriquí
- Research Group on Plant Biology Under Mediterranean Conditions, Universitat de les Illes Balears - Instituto de Investigaciones Agroambientales y de Economía del Agua (UIB-INAGEA), Carretera de Valldemossa Km 7.5, 07122, Palma, Spain
- School of Biological Sciences, University of Tasmania, Private Bag 51, 7001, Hobart, TAS, Australia
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47
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Knauer J, Zaehle S, De Kauwe MG, Haverd V, Reichstein M, Sun Y. Mesophyll conductance in land surface models: effects on photosynthesis and transpiration. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:858-873. [PMID: 31659806 DOI: 10.1111/tpj.14587] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 10/10/2019] [Accepted: 10/17/2019] [Indexed: 05/08/2023]
Abstract
The CO2 transfer conductance within plant leaves (mesophyll conductance, gm ) is currently not considered explicitly in most land surface models (LSMs), but instead treated implicitly as an intrinsic property of the photosynthetic machinery. Here, we review approaches to overcome this model deficiency by explicitly accounting for gm , which comprises the re-adjustment of photosynthetic parameters and a model describing the variation of gm in dependence of environmental conditions. An explicit representation of gm causes changes in the response of photosynthesis to environmental factors, foremost leaf temperature, and ambient CO2 concentration, which are most pronounced when gm is small. These changes in leaf-level photosynthesis translate into a stronger climate and CO2 response of gross primary productivity (GPP) and transpiration at the global scale. The results from two independent studies show consistent latitudinal patterns of these effects with biggest differences in GPP in the boreal zone (up to ~15%). Transpiration and evapotranspiration show spatially similar, but attenuated, changes compared with GPP. These changes are indirect effects of gm caused by the assumed strong coupling between stomatal conductance and photosynthesis in current LSMs. Key uncertainties in these simulations are the variation of gm with light and the robustness of its temperature response across plant types and growth conditions. Future research activities focusing on the response of gm to environmental factors and its relation to other plant traits have the potential to improve the representation of photosynthesis in LSMs and to better understand its present and future role in the Earth system.
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Affiliation(s)
- Jürgen Knauer
- CSIRO Oceans and Atmosphere, Canberra, ACT, 2601, Australia
- Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, 07745, Jena, Germany
| | - Sönke Zaehle
- Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, 07745, Jena, Germany
- Michael-Stifel Center Jena for Data-Driven and Simulation Science, 07745, Jena, Germany
| | - Martin G De Kauwe
- ARC Centre of Excellence for Climate Extremes and the Climate Change Research Centre, University of New South Wales, Sydney, 2052, NSW, Australia
| | - Vanessa Haverd
- CSIRO Oceans and Atmosphere, Canberra, ACT, 2601, Australia
| | - Markus Reichstein
- Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, 07745, Jena, Germany
- Michael-Stifel Center Jena for Data-Driven and Simulation Science, 07745, Jena, Germany
| | - Ying Sun
- School of Integrative Plant Science, Soil and Crop Sciences Section, Cornell University, Ithaca, NY, 14850, USA
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48
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Pathare VS, Koteyeva N, Cousins AB. Increased adaxial stomatal density is associated with greater mesophyll surface area exposed to intercellular air spaces and mesophyll conductance in diverse C 4 grasses. THE NEW PHYTOLOGIST 2020; 225:169-182. [PMID: 31400232 DOI: 10.1111/nph.16106] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 08/01/2019] [Indexed: 05/21/2023]
Abstract
Mesophyll conductance (gm ) is the diffusion of CO2 from intercellular air spaces (IAS) to the first site of carboxylation in the mesophyll cells. In C3 species, gm is influenced by diverse leaf structural and anatomical traits; however, little is known about traits affecting gm in C4 species. To address this knowledge gap, we used online oxygen isotope discrimination measurements to estimate gm and microscopy techniques to measure leaf structural and anatomical traits potentially related to gm in 18 C4 grasses. In this study, gm scaled positively with photosynthesis and intrinsic water-use efficiency (TEi ), but not with stomatal conductance. Also, gm was not determined by a single trait but was positively correlated with adaxial stomatal densities (SDada ), stomatal ratio (SR), mesophyll surface area exposed to IAS (Smes ) and leaf thickness. However, gm was not related to abaxial stomatal densities (SDaba ) and mesophyll cell wall thickness (TCW ). Our study suggests that greater SDada and SR increased gm by increasing Smes and creating additional parallel pathways for CO2 diffusion inside mesophyll cells. Thus, SDada , SR and Smes are important determinants of C4 -gm and could be the target traits selected or modified for achieving greater gm and TEi in C4 species.
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Affiliation(s)
- Varsha S Pathare
- School of Biological Sciences, Washington State University, Pullman, WA, 99164-4236, USA
| | - Nuria Koteyeva
- School of Biological Sciences, Washington State University, Pullman, WA, 99164-4236, USA
- Laboratory of Anatomy and Morphology, V.L. Komarov Botanical Institute of the Russian Academy of Sciences, 197376, St Petersburg, Russia
| | - Asaph B Cousins
- School of Biological Sciences, Washington State University, Pullman, WA, 99164-4236, USA
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Zhou Q, Jiang Z, Zhang X, Lai Q, Li Y, Zhao F, Zhao Z. Tree age did not affect the leaf anatomical structure or ultrastructure of Platycladus orientalis L. (Cupressaceae). PeerJ 2019; 7:e7938. [PMID: 31681514 PMCID: PMC6824329 DOI: 10.7717/peerj.7938] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 09/23/2019] [Indexed: 11/20/2022] Open
Abstract
Tree aging is a new research area and has attracted research interest in recent years. Trees show extraordinary longevity; Platycladus orientalis L. (Cupressaceae) has a lifespan of thousands of years. Ancient trees are precious historical heritage and scientific research materials. However, tree aging and tree senescence have different definitions and are poorly understood. Since leaves are the most sensitive organ of a tree, we studied the structural response of leaves to tree age. Experiments investigating the leaf morphological structure, anatomical structure and ultrastructure were conducted in healthy P. orientalis at three different ages (ancient trees >2,000 years, 200 years < middle-aged trees <500 years, young trees <50 years) at the world’s largest planted pure forest in the Mausoleum of the Yellow Emperor, Shaanxi Province, China. Interestingly, tree age did not significantly impact leaf cellular structure. Ancient P. orientalis trees in forests older than 2,000 years still have very strong vitality, and their leaves still maintained a perfect anatomical structure and ultrastructure. Our observations provide new evidence for the unique pattern of tree aging, especially healthy aging. Understanding the relationships between leaf structure and tree age will enhance the understanding of tree aging.
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Affiliation(s)
- Qianyi Zhou
- Key Comprehensive Laboratory of Forestry, College of Forestry, Northwest Agricultural and Forestry University, Yang Ling, Shaanxi, China
| | - Zhaohong Jiang
- College of Life Science, Northwest Agriculture and Forestry University, Yangling, Shaanxi, China
| | - Xin Zhang
- Key Comprehensive Laboratory of Forestry, College of Forestry, Northwest Agricultural and Forestry University, Yang Ling, Shaanxi, China
| | - Qing Lai
- Key Comprehensive Laboratory of Forestry, College of Forestry, Northwest Agricultural and Forestry University, Yang Ling, Shaanxi, China
| | - Yiming Li
- Key Comprehensive Laboratory of Forestry, College of Forestry, Northwest Agricultural and Forestry University, Yang Ling, Shaanxi, China
| | - Fei Zhao
- Beijing Agricultural Technology Extension Station, Beijing, China
| | - Zhong Zhao
- Key Comprehensive Laboratory of Forestry, College of Forestry, Northwest Agricultural and Forestry University, Yang Ling, Shaanxi, China
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50
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Yiotis C, McElwain JC. A Novel Hypothesis for the Role of Photosynthetic Physiology in Shaping Macroevolutionary Patterns. PLANT PHYSIOLOGY 2019; 181:1148-1162. [PMID: 31484680 PMCID: PMC6836816 DOI: 10.1104/pp.19.00749] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 08/25/2019] [Indexed: 05/08/2023]
Abstract
The fossil record and models of atmospheric concentrations of O2 and CO2 suggest that past shifts in plant ecological dominance often coincided with dramatic changes in Earth's atmospheric composition. This study tested the effects of past changes in atmospheric composition on the photosynthetic physiology of a limited range of early-diverging angiosperms (eight), gymnosperms (three), and ferns (two). We performed physiological measurements on all species and used the results to parameterize simulations of their photosynthetic paleophysiology using three independent modeling approaches. Unique physiological attributes were identified for the three evolutionary groups: angiosperm taxa displayed significantly higher mesophyll conductance (g m), yet their stomatal conductance (g s) was lower than that of ferns. Gymnosperm taxa displayed low g s and g m, but they partially offset their significant diffusional limitations on photosynthesis through their higher maximum Rubisco carboxylation rate. Despite their high total conductance to CO2, fern taxa lacked an optimized control of g s, which was reflected in their low intrinsic water use efficiency. Simulations of the photosynthetic physiology of ferns, angiosperms, and gymnosperms through Earth's history demonstrated that past fluctuations in O2 and CO2 concentrations may have resulted in significant shifts in the relative competitiveness of the three evolutionary groups. Although preliminary because of limited species sampling, these findings hint at a potential mechanistic basis for the observed broad temporal correlation between atmospheric change and shifts in plant evolutionary group-level richness observed in the fossil record and are presented as a framework to be tested with paleophotosynthetic proxies and through increased species sampling.
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Affiliation(s)
- Charilaos Yiotis
- Botany Department, School of Natural Sciences, Trinity College, Dublin 2, Ireland
| | - Jennifer C McElwain
- Botany Department, School of Natural Sciences, Trinity College, Dublin 2, Ireland
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