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Liu Z, Zhao M, Tennakoon K, Liu C. Climate factors determine large-scale spatial patterns of stomatal index in Chinese herbaceous and woody dicotyledonous plants. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 949:175112. [PMID: 39084391 DOI: 10.1016/j.scitotenv.2024.175112] [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: 04/15/2024] [Revised: 07/03/2024] [Accepted: 07/27/2024] [Indexed: 08/02/2024]
Abstract
The stomatal index (SI, %) and its response to climate factors (temperature and precipitation) can help our understanding of terrestrial carbon and water cycling and plant adaptation in the ecosystem, however, consensus has not yet been reached in this regard. In this study, we compiled an extensive dataset from the Chinese flora to investigate the response of SI to environmental change, including 891 herbaceous and woody species from 188 published papers. The results showed that mean values of the adaxial SI and abaxial SI for all species were 14.06 and 19.22, respectively, and the ratio of adaxial to abaxial SI was 0.84. For the adaxial SI, abaxial SI, and the ratio of adaxial to abaxial SI, the range of these values varied between 0.05-43.67, 0.01-48.17, and 0.03-4.31, respectively. Compared with woody plants, herbaceous plants showed higher values in both adaxial and abaxial SI. In terms of the impact of climate factors, the abaxial SI of herbaceous plants changed slower than the adaxial SI, while woody plants showed the opposite trend. Threshold effects of increased temperature and precipitation on SI were observed, indicating that SI responded differently to changes in climate factors at different levels. Climate factors play a crucial role in driving the adaxial SI than abaxial SI. Our findings highlight the significant challenges posed by divergent responses of SI in forecasting future water and carbon cycles associated with climatic and environmental change.
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Affiliation(s)
- Zhaogang Liu
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China; Co-Innovation Center for Sustainable Forestry in Southern China, Laboratory of Biodiversity and Conservation, College of Ecology and Environment, Nanjing Forestry University, Nanjing 210037, China; Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ming Zhao
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Kushan Tennakoon
- Institute of Innovation, Science and Sustainability, Federation University Australia Berwick Campus, No.100 Clyde Road, Berwick, VIC 3806, Australia
| | - Congcong Liu
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China.
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2
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Askanbayeva B, Janová J, Kubásek J, Zeisler-Diehl VV, Schreiber L, Muir CD, Šantrůček J. Amphistomy: stomata patterning inferred from 13C content and leaf-side-specific deposition of epicuticular wax. ANNALS OF BOTANY 2024; 134:437-454. [PMID: 38836501 PMCID: PMC11341673 DOI: 10.1093/aob/mcae082] [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: 12/14/2023] [Accepted: 06/04/2024] [Indexed: 06/06/2024]
Abstract
BACKGROUND AND AIMS The benefits and costs of amphistomy (AS) vs. hypostomy (HS) are not fully understood. Here, we quantify benefits of access of CO2 through stomata on the upper (adaxial) leaf surface, using 13C abundance in the adaxial and abaxial epicuticular wax. Additionally, a relationship between the distribution of stomata and epicuticular wax on the opposite leaf sides is studied. METHODS We suggest that the 13C content of long-chain aliphatic compounds of cuticular wax records the leaf internal CO2 concentration in chloroplasts adjacent to the adaxial and abaxial epidermes. This unique property stems from: (1) wax synthesis being located exclusively in epidermal cells; and (2) ongoing wax renewal over the whole leaf lifespan. Compound-specific and bulk wax 13C abundance (δ) was related to amphistomy level (ASL; as a fraction of adaxial in all stomata) of four AS and five HS species grown under various levels of irradiance. The isotopic polarity of epicuticular wax, i.e. the difference in abaxial and adaxial δ (δab - δad), was used to calculate the leaf dorsiventral CO2 gradient. Leaf-side-specific epicuticular wax deposition (amphiwaxy level) was estimated and related to ASL. KEY RESULTS In HS species, the CO2 concentration in the adaxial epidermis was lower than in the abaxial one, independently of light conditions. In AS leaves grown in high-light and low-light conditions, the isotopic polarity and CO2 gradient varied in parallel with ASL. The AS leaves grown in high-light conditions increased ASL compared with low light, and δab - δad approached near-zero values. Changes in ASL occurred concomitantly with changes in amphiwaxy level. CONCLUSIONS Leaf wax isotopic polarity is a newly identified leaf trait, distinguishing between hypo- and amphistomatous species and indicating that increased ASL in sun-exposed AS leaves reduces the CO2 gradient across the leaf mesophyll. Stomata and epicuticular wax deposition follow similar leaf-side patterning.
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Affiliation(s)
- Balzhan Askanbayeva
- Department of Experimental Plant Biology, Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic
| | - Jitka Janová
- Department of Experimental Plant Biology, Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic
| | - Jiří Kubásek
- Department of Experimental Plant Biology, Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic
| | - Viktoria V Zeisler-Diehl
- Institute of Cellular and Molecular Botany, University of Bonn, Kirschallee 1, 53115 Bonn, Germany
| | - Lukas Schreiber
- Institute of Cellular and Molecular Botany, University of Bonn, Kirschallee 1, 53115 Bonn, Germany
| | - Christopher D Muir
- Department of Botany, University of Wisconsin, 143 Lincoln Drive, Madison, WI 53711, USA
| | - Jiří Šantrůček
- Department of Experimental Plant Biology, Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic
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3
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Tulva I, Koolmeister K, Hõrak H. Low relative air humidity and increased stomatal density independently hamper growth in young Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024. [PMID: 39072887 DOI: 10.1111/tpj.16944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 06/26/2024] [Accepted: 07/13/2024] [Indexed: 07/30/2024]
Abstract
Stomatal pores in plant leaves mediate CO2 uptake for photosynthesis and water loss via transpiration. Altered stomatal density can affect plant photosynthetic capacity, water use efficiency, and growth, potentially providing either benefits or drawbacks depending on the environment. Here we explore, at different air humidity regimes, gas exchange, stomatal anatomy, and growth of Arabidopsis lines designed to combine increased stomatal density (epf1, epf2) with high stomatal sensitivity (ht1-2, cyp707a1/a3). We show that the stomatal density and sensitivity traits combine as expected: higher stomatal density increases stomatal conductance, whereas the effect is smaller in the high stomatal sensitivity mutant backgrounds than in the epf1epf2 double mutant. Growth under low air humidity increases plant stomatal ratio with relatively more stomata allocated to the adaxial epidermis. Low relative air humidity and high stomatal density both independently impair plant growth. Higher evaporative demand did not punish increased stomatal density, nor did inherently low stomatal conductance provide any protection against low relative humidity. We propose that the detrimental effects of high stomatal density on plant growth at a young age are related to the cost of producing stomata; future experiments need to test if high stomatal densities might pay off in later life stages.
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Affiliation(s)
- Ingmar Tulva
- Institute of Technology, University of Tartu, Nooruse 1, 50411, Tartu, Estonia
| | - Kaspar Koolmeister
- Institute of Technology, University of Tartu, Nooruse 1, 50411, Tartu, Estonia
- Institute of Bioengineering, University of Tartu, Nooruse 1, 50411, Tartu, Estonia
| | - Hanna Hõrak
- Institute of Technology, University of Tartu, Nooruse 1, 50411, Tartu, Estonia
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4
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Coiro M, McLoughlin S, Steinthorsdottir M, Vajda V, Fabrikant D, Seyfullah LJ. Parallel evolution of angiosperm-like venation in Peltaspermales: a reinvestigation of Furcula. THE NEW PHYTOLOGIST 2024; 242:2845-2856. [PMID: 38623034 DOI: 10.1111/nph.19726] [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: 09/05/2023] [Accepted: 03/15/2024] [Indexed: 04/17/2024]
Abstract
Leaf venation is a pivotal trait in the success of vascular plants. Whereas gymnosperms have single or sparsely branched parallel veins, angiosperms developed a hierarchical structure of veins that form a complex reticulum. Its physiological consequences are considered to have enabled angiosperms to dominate terrestrial ecosystems in the Late Cretaceous and Cenozoic. Although a hierarchical-reticulate venation also occurs in some groups of extinct seed plants, it is unclear whether these are stem relatives of angiosperms or have evolved these traits in parallel. Here, we re-examine the morphology of the enigmatic foliage taxon Furcula, a potential early Mesozoic angiosperm relative, and argue that its hierarchical vein network represents convergent evolution (in the Late Triassic) with flowering plants (which developed in the Early Cretaceous) based on details of vein architecture and the absence of angiosperm-like stomata and guard cells. We suggest that its nearest relatives are Peltaspermales similar to Scytophyllum and Vittaephyllum, the latter being a genus that originated during the Late Triassic (Carnian) and shares a hierarchical vein system with Furcula. We further suggest that the evolution of hierarchical venation systems in the early Permian, the Late Triassic, and the Early Cretaceous represent 'natural experiments' that might help resolve the selective pressures enabling this trait to evolve.
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Affiliation(s)
- Mario Coiro
- Department of Palaeontology, University of Vienna, 1090, Vienna, Austria
- Ronin Institute for Independent Scholarship, Montclair, NJ, 07043, USA
| | - Stephen McLoughlin
- Department of Palaeobiology, Swedish Museum of Natural History, 114 18, Stockholm, Sweden
| | - Margret Steinthorsdottir
- Department of Bioinformatics and Genetics, Swedish Museum of Natural History, 114 18, Stockholm, Sweden
- Bolin Centre for Climate Research, Stockholm University, 114 19, Stockholm, Sweden
| | - Vivi Vajda
- Department of Palaeobiology, Swedish Museum of Natural History, 114 18, Stockholm, Sweden
| | - Dolev Fabrikant
- The Hebrew University of Jerusalem, Jerusalem, 9190501, Israel
| | - Leyla J Seyfullah
- Department of Palaeontology, University of Vienna, 1090, Vienna, Austria
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5
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Triplett G, Buckley TN, Muir CD. Amphistomy increases leaf photosynthesis more in coastal than montane plants of Hawaiian 'ilima (Sida fallax). AMERICAN JOURNAL OF BOTANY 2024; 111:e16284. [PMID: 38351495 DOI: 10.1002/ajb2.16284] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 12/19/2023] [Accepted: 12/19/2023] [Indexed: 02/22/2024]
Abstract
PREMISE The adaptive significance of amphistomy (stomata on both upper and lower leaf surfaces) is unresolved. A widespread association between amphistomy and open, sunny habitats suggests the adaptive benefit of amphistomy may be greatest in these contexts, but this hypothesis has not been tested experimentally. Understanding amphistomy informs its potential as a target for crop improvement and paleoenvironment reconstruction. METHODS We developed a method to quantify "amphistomy advantage" (AA $\text{AA}$ ) as the log-ratio of photosynthesis in an amphistomatous leaf to that of the same leaf but with gas exchange blocked through the upper surface (pseudohypostomy). Humidity modulated stomatal conductance and thus enabled comparing photosynthesis at the same total stomatal conductance. We estimatedAA $\text{AA}$ and leaf traits in six coastal (open, sunny) and six montane (closed, shaded) populations of the indigenous Hawaiian species 'ilima (Sida fallax). RESULTS Coastal 'ilima leaves benefit 4.04 times more from amphistomy than montane leaves. Evidence was equivocal with respect to two hypotheses: (1) that coastal leaves benefit more because they are thicker and have lower CO2 conductance through the internal airspace and (2) that they benefit more because they have similar conductance on each surface, as opposed to most conductance being through the lower surface. CONCLUSIONS This is the first direct experimental evidence that amphistomy increases photosynthesis, consistent with the hypothesis that parallel pathways through upper and lower mesophyll increase CO2 supply to chloroplasts. The prevalence of amphistomatous leaves in open, sunny habitats can partially be explained by the increased benefit of amphistomy in "sun" leaves, but the mechanistic basis remains uncertain.
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Affiliation(s)
- Genevieve Triplett
- School of Life Sciences, University of Hawai'i Mānoa, Honolulu, HI, 96822, USA
| | - Thomas N Buckley
- Department of Plant Sciences, University of California, Davis, CA, 95616, USA
| | - Christopher D Muir
- School of Life Sciences, University of Hawai'i Mānoa, Honolulu, HI, 96822, USA
- Department of Botany, University of Wisconsin, Madison, WI, 53706, USA
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6
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Lajoie G, Kembel SW. Data-driven identification of major axes of functional variation in bacteria. Environ Microbiol 2023; 25:2580-2591. [PMID: 37648438 DOI: 10.1111/1462-2920.16487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 07/26/2023] [Indexed: 09/01/2023]
Abstract
The discovery of major axes of correlated functional variation among species and habitats has revealed the fundamental trade-offs structuring both functional and taxonomic diversity in eukaryotes such as plants. Whether such functional axes exist in the bacterial realm and whether they could explain bacterial taxonomic turnover among ecosystems remains unknown. Here, we use a data-driven approach to leverage global genomic and metagenomic datasets to reveal the existence of major axes of functional variation explaining both evolutionary differentiation within Bacteria and their ecological sorting across diverse habitats. We show that metagenomic variation among bacterial communities from various ecosystems is structured along a few axes of correlated functional pathways. Similar clusters of traits explained phylogenetic trait variation among >16,000 bacterial genomes, suggesting that functional turnover among bacterial communities from distinct habitats does not only result from the differential filtering of similar functions among communities, but also from phylogenetic correlations among these functions. Concordantly, functional pathways associated with trait clusters that were most important for defining functional turnover among bacterial communities were also those that had the highest phylogenetic signal in the bacterial genomic phylogeny. This study overall underlines the important role of evolutionary history in shaping contemporary distributions of bacteria across ecosystems.
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Affiliation(s)
- Geneviève Lajoie
- Département des Sciences Biologiques, Université du Québec à Montréal, Montréal, Canada
| | - Steven W Kembel
- Département des Sciences Biologiques, Université du Québec à Montréal, Montréal, Canada
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7
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Fetter KC, Keller SR. Admixture mapping and selection scans identify genomic regions associated with stomatal patterning and disease resistance in hybrid poplars. Ecol Evol 2023; 13:e10579. [PMID: 37881228 PMCID: PMC10597741 DOI: 10.1002/ece3.10579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 09/18/2023] [Accepted: 09/21/2023] [Indexed: 10/27/2023] Open
Abstract
Variation in fitness components can be linked in some cases to variation in key traits. Metric traits that lie at the intersection of development, defense, and ecological interactions may be expected to experience environmental selection, informing our understanding of evolutionary and ecological processes. Here, we use quantitative genetic and population genomic methods to investigate disease dynamics in hybrid and non-hybrid populations. We focus our investigation on morphological and ecophysiological traits which inform our understanding of physiology, growth, and defense against a pathogen. In particular, we investigate stomata, microscopic pores on the surface of a leaf that regulate gas exchange during photosynthesis and are sites of entry for various plant pathogens. Stomatal patterning traits were highly predictive of disease risk. Admixture mapping identified a polygenic basis of disease resistance. Candidate genes for stomatal and disease resistance map to the same genomic regions and experienced positive selection. Genes with functions to guard cell homeostasis, the plant immune system, components of constitutive defenses, and growth-related transcription factors were identified. Our results indicate positive selection acted on candidate genes for stomatal patterning and disease resistance, potentially acting in concert to structure their variation in naturally formed backcrossing hybrid populations.
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Affiliation(s)
- Karl C. Fetter
- Department of Plant BiologyUniversity of VermontBurlingtonVermontUSA
- Department of Ecology and Evolutionary BiologyUniversity of ConnecticutStorrsConnecticutUSA
| | - Stephen R. Keller
- Department of Plant BiologyUniversity of VermontBurlingtonVermontUSA
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8
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Wang X, Wu T, Asim M, Ling A, Sun Y, Shi Y, Yan H. The asymmetric photosynthetic characteristics of the isobilateral sorghum leaves under the illumination of the diffuse light. FRONTIERS IN PLANT SCIENCE 2023; 14:1218076. [PMID: 37521922 PMCID: PMC10374316 DOI: 10.3389/fpls.2023.1218076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 06/19/2023] [Indexed: 08/01/2023]
Abstract
The difference between photosynthesis on the two leaf sides (dorsoventral asymmetry) of photosynthesis is important for light-use patterns, but the asymmetry is environment dependent. Its role in photosynthetic regulation has been intensively studied, but little is known about the impacts of direct and diffuse light on the asymmetry. Because of the current changing fraction of diffuse light in sky radiation, this study investigated the dorsoventral asymmetry of photosynthetic traits under direct and diffuse light conditions in an important food and energy crop, Sorghum bicolor L. A unique method was used to investigate the specific gas exchange of each leaf surface. Anatomical and morphological traits were different between the two surfaces of sorghum leaves, which might result in photosynthetic asymmetry. The variations in photosynthetic rates and stomatal conductance were significant between the two surfaces in direct and diffuse light, but the degree of dorsoventral asymmetry decreased in diffuse light. The integrated P N and G s of the adaxial illumination were significantly higher than that of abaxial illumination both in direct and diffuse light in sorghum leaves, but the ASI of the integrated P Nwas 2.83 in direct light, while significantly dropped to 1.69 in diffuse light. Significant morphological differences between the two surfaces might cause photosynthetic asymmetry in the sorghum leaves. The variations of specific gas exchange were significant between direct and diffuse light, including in the incident and self-transmitted light. Compared with direct light, diffuse light reduced the stomatal sensitivity, with the degree of decline being greater in the adaxial surface, which caused weak dorsoventral asymmetry in photosynthesis. The specific photosynthetic characteristics in sorghum leaves varied obviously in direct and diffuse light, including in the incident and self-transmitted light, which contributed to the different overall gas exchange. Compared with direct light, the decline of stomatal sensitivity, which showed positive correlation with stomatal density, caused weakened dorsoventral asymmetry in photosynthesis in diffuse light. The findings provide new insights into dorsoventral asymmetry and the impact of diffuse light on photosynthesis in isobilateral leaves.
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Affiliation(s)
- Xiaolin Wang
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, China
| | - Tao Wu
- Research and Development of Center, Liangshan Branch of Sichuan Tobacco Company, Xichang, China
| | - Muhammad Asim
- Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Aifen Ling
- Research and Development of Center, Liangshan Branch of Sichuan Tobacco Company, Xichang, China
| | - Yanguo Sun
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, China
| | - Yi Shi
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, China
| | - Huifeng Yan
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, China
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9
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Liu C, Sack L, Li Y, He N. Contrasting adaptation and optimization of stomatal traits across communities at continental scale. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:6405-6416. [PMID: 35716087 DOI: 10.1093/jxb/erac266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 06/15/2022] [Indexed: 06/15/2023]
Abstract
Shifts in stomatal trait distributions across contrasting environments and their linkage with ecosystem productivity at large spatial scales have been unclear. Here, we measured the maximum stomatal conductance (g), stomatal area fraction (f), and stomatal space-use efficiency (e, the ratio of g to f) of 800 plant species ranging from tropical to cold-temperate forests, and determined their values for community-weighted mean, variance, skewness, and kurtosis. We found that the community-weighted means of g and f were higher in drier sites, and thus, that drought 'avoidance' by water availability-driven growth pulses was the dominant mode of adaptation for communities at sites with low water availability. Additionally, the variance of g and f was also higher at arid sites, indicating greater functional niche differentiation, whereas that for e was lower, indicating the convergence in efficiency. When all other stomatal trait distributions were held constant, increasing kurtosis or decreasing skewness of g would improve ecosystem productivity, whereas f showed the opposite patterns, suggesting that the distributions of inter-related traits can play contrasting roles in regulating ecosystem productivity. These findings demonstrate the climatic trends of stomatal trait distributions and their significance in the prediction of ecosystem productivity.
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Affiliation(s)
- Congcong Liu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lawren Sack
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90025, USA
| | - Ying Li
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Nianpeng He
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
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10
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Wall S, Vialet‐Chabrand S, Davey P, Van Rie J, Galle A, Cockram J, Lawson T. Stomata on the abaxial and adaxial leaf surfaces contribute differently to leaf gas exchange and photosynthesis in wheat. THE NEW PHYTOLOGIST 2022; 235:1743-1756. [PMID: 35586964 PMCID: PMC9545378 DOI: 10.1111/nph.18257] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 04/06/2022] [Indexed: 05/12/2023]
Abstract
Although stomata are typically found in greater numbers on the abaxial surface, wheat flag leaves have greater densities on the adaxial surface. We determine the impact of this less common stomatal patterning on gaseous fluxes using a novel chamber that simultaneously measures both leaf surfaces. Using a combination of differential illuminations and CO2 concentrations at each leaf surface, we found that mesophyll cells associated with the adaxial leaf surface have a higher photosynthetic capacity than those associated with the abaxial leaf surface, which is supported by an increased stomatal conductance (driven by differences in stomatal density). When vertical gas flux at the abaxial leaf surface was blocked, no compensation by adaxial stomata was observed, suggesting each surface operates independently. Similar stomatal kinetics suggested some co-ordination between the two surfaces, but factors other than light intensity played a role in these responses. Higher photosynthetic capacity on the adaxial surface facilitates greater carbon assimilation, along with higher adaxial stomatal conductance, which would also support greater evaporative leaf cooling to maintain optimal leaf temperatures for photosynthesis. Furthermore, abaxial gas exchange contributed c. 50% to leaf photosynthesis and therefore represents an important contributor to overall leaf gas exchange.
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Affiliation(s)
- Shellie Wall
- School of Life SciencesUniversity of EssexColchesterCO4 3SQUK
| | | | - Phillip Davey
- School of Life SciencesUniversity of EssexColchesterCO4 3SQUK
| | - Jeroen Van Rie
- BASF BBCC – Innovation Center GentTechnologiepark‐Zwijnaarde 1019052GhentBelgium
| | - Alexander Galle
- BASF BBCC – Innovation Center GentTechnologiepark‐Zwijnaarde 1019052GhentBelgium
| | | | - Tracy Lawson
- School of Life SciencesUniversity of EssexColchesterCO4 3SQUK
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11
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Teboul N, Magder A, Zilberberg M, Peleg Z. Elucidating the pleiotropic effects of sesame KANADI1 locus on leaf and capsule development. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 110:88-102. [PMID: 34964536 DOI: 10.1111/tpj.15655] [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: 01/12/2021] [Revised: 12/15/2021] [Accepted: 12/17/2021] [Indexed: 06/14/2023]
Abstract
Autonomous seed dispersal is a critical trait for wild plants in natural ecosystems; however, for domesticated crop-plants it can lead to significant yield losses. While seed shattering was a major selection target during the initial domestication of many crops, this trait is still targeted in breeding programs, especially in 'orphan crops' such as sesame, whose capsules dehisce upon ripening. Here we used a mapping population derived from a cross between wild-type (dehiscent) × indehiscent lines to test the hypothesis that the selection against indehiscent alleles in sesame is a consequence of complex genetic interactions associated with yield reduction. We identified a major pleiotropic locus, SiKANADI1, associated with abnormal hyponastic leaf and indehiscent capsule, and genetically dissected its underlying mechanism using a set of near-isogenic lines. Transcriptional, anatomical and physiological information shed light, for the first time, on the polar regulatory gene network in sesame. The pleiotropic effect of SiKANADI1 on leaf and capsule structure and its influence on photosynthetic capacity and final yield are thoroughly characterized. Overall, our results provide new insights on the genetic and morphological mechanisms regulating capsule indehiscence in sesame, and discuss their evolutionary consequences and potential for future sesame breeding.
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Affiliation(s)
- Naama Teboul
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, 7610001, Israel
| | - Asher Magder
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, 7610001, Israel
| | - Michael Zilberberg
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, 7610001, Israel
| | - Zvi Peleg
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, 7610001, Israel
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12
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Grünhofer P, Herzig L, Sent S, Zeisler-Diehl VV, Schreiber L. Increased cuticular wax deposition does not change residual foliar transpiration. PLANT, CELL & ENVIRONMENT 2022; 45:1157-1171. [PMID: 35102563 DOI: 10.1111/pce.14274] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 01/19/2022] [Accepted: 01/28/2022] [Indexed: 06/14/2023]
Abstract
The effect of contrasting environmental growth conditions (in vitro tissue culture, ex vitro acclimatisation, climate chamber, greenhouse and outdoor) on leaf development, cuticular wax composition, and foliar transpiration of detached leaves of the Populus × canescens clone 84 K were investigated. Our results show that total amounts of cuticular wax increased more than 10-fold when cultivated in different growth conditions, whereas qualitative wax composition did not change. With exception of plants directly taken from tissue culture showing rapid dehydration, rates of water loss (residual foliar transpiration) of intact but detached leaves were constant and independent from growth conditions and thus independent from increasing wax amounts. Since cuticular transpiration measured with isolated astomatous P. × canescens cuticles was identical to residual foliar transpiration rates of detached leaves, our results confirm that cuticular transpiration of P. × canescens leaves can be predicted with high accuracy from residual transpiration of detached leaves after stomatal closure. Our results convincingly show that more than 10-fold increased wax amounts in P. × canescens cuticles do not lead to decreased rates of residual (cuticular) transpiration.
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Affiliation(s)
- Paul Grünhofer
- Department of Ecophysiology, Institute of Cellular and Molecular Botany, University of Bonn, Bonn, Germany
| | - Lena Herzig
- Department of Ecophysiology, Institute of Cellular and Molecular Botany, University of Bonn, Bonn, Germany
| | - Sophie Sent
- Department of Ecophysiology, Institute of Cellular and Molecular Botany, University of Bonn, Bonn, Germany
| | - Viktoria V Zeisler-Diehl
- Department of Ecophysiology, Institute of Cellular and Molecular Botany, University of Bonn, Bonn, Germany
| | - Lukas Schreiber
- Department of Ecophysiology, Institute of Cellular and Molecular Botany, University of Bonn, Bonn, Germany
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13
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Proença CEB, Tuler AC, Lucas EJ, Vasconcelos TNDC, de Faria JEQ, Staggemeier VG, de-Carvalho PS, Forni-Martins ER, Inglis PW, da Mata LR, da Costa IR. Diversity, phylogeny and evolution of the rapidly evolving genus Psidium L. (Myrtaceae, Myrteae). ANNALS OF BOTANY 2022; 129:367-388. [PMID: 35034117 PMCID: PMC8944734 DOI: 10.1093/aob/mcac005] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 01/14/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND AND AIMS Psidium is the fourthth largest genus of Myrtaceae in the Neotropics. Psidium guajava is widely cultivated in the tropics for its edible fruit. It is commercially under threat due to the disease guava decline. Psidium cattleyanum is one of the 100 most invasive organisms in the world. Knowledge of the phylogenetic relationships within Psidium is poor. We aim to provide a review of the biology, morphology and ecology of Psidium, a phylogenetic tree, an infrageneric classification and a list of species. METHODS Morphological and geographic data were obtained by studying Psidium in herbaria and in the field between 1988 and 2020. Forty-six herbaria were visited personally. A database of approx. 6000 specimens was constructed, and the literature was reviewed. Thirty species (about a third of the species in the genus) were sampled for molecular phylogenetic inference. Two chloroplast (psbA-trnH and ndhF) and two nuclear (external transcribed spacer and internal transcribed spacer) regions were targeted. Phylogenetic trees were constructed using maximum likelihood (ML; RaxML) and Bayesian inference (BI; MrBayes). KEY RESULTS Psidium is a monophyletic genus with four major clades recognized as sections. Section Psidium (ten species), to which P. guajava belongs, is sister to the rest of the genus; it is widespread across the Neotropics. Section Obversifolia (six species; restricted to the Brazilian Atlantic Forest), which includes P. cattleyanum, is sister to the innermost clade composed of sister sections Apertiflora (31 species; widespread but most diverse in the Brazilian Atlantic Forest) + Mitranthes (26 species; widespread in dry forests and probably diverse in the Caribbean). Characters associated with diversification within Psidium are discussed. CONCLUSIONS Research on pre-foliation, colleters, leaf anatomy, leaf physiology, staminal development, placentation and germination associated with the anatomy of the opercular plug is desirable. Studies are biased towards sections Psidium and Obversifolia, with other sections poorly known.
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Affiliation(s)
| | - Amélia Carlos Tuler
- Instituto Nacional da Mata Atlântica, Av. José Ruschi 4, Santa Teresa, ES, CEP, Brazil
| | | | | | | | - Vanessa Graziele Staggemeier
- Departamento de Ecologia, Universidade Federal do Rio Grande do Norte, R. das Biociências, Lagoa Nova, Natal, RN, CEP, Brazil
| | | | | | | | - Lorena Ramos da Mata
- Empresa Brasileira de Pesquisa Agropecuária, Recursos Genéticos e Biotecnologia (EMBRAPA CENARGEN)
, SAIN Parque Rural, W5, Asa Norte, Brasília, DF, Brazil
| | - Itayguara Ribeiro da Costa
- Departamento de Biologia, Universidade Federal do Ceará, Campus do Pici Bloco 906, Fortaleza, CE, Brazil
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14
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Doll Y, Koga H, Tsukaya H. Callitriche as a potential model system for evolutionary studies on the dorsiventral distribution of stomata. PLANT SIGNALING & BEHAVIOR 2021; 16:1978201. [PMID: 34538209 PMCID: PMC8525970 DOI: 10.1080/15592324.2021.1978201] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 09/03/2021] [Accepted: 09/04/2021] [Indexed: 06/13/2023]
Abstract
Controlling the distribution of stomata is crucial for the adaptation of plants to new, or changing environments. While many plant species produce stomata predominantly on the abaxial leaf surface (hypostomy), some produce stomata on both surfaces (amphistomy), and the remaining few produce them only on the adaxial surface (hyperstomy). Various selective pressures have driven the evolution of these three modes of stomatal distribution. Despite recent advances in our understanding of stomatal development and dorsiventral leaf polarity, the genetic basis for the evolution of different stomatal distributions is still unclear. Here, we propose the genus Callitriche as a new model system to investigate patterns in the evolution of stomatal distribution. Callitriche comprises species with diverse lifestyles, including terrestrial, amphibious, and obligately aquatic plants. We found that species in this genus cover all three modes of dorsiventral stomatal distribution, making it a desirable model for comparative and evolutionary analyses on distribution modes. We further characterized the genetic basis of the different distribution modes, focusing on the stomatal key transcription factor SPEECHLESS. Future research using the promising model system Callitriche would open a new direction for evolutionary developmental biology studies on stomata.
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Affiliation(s)
- Yuki Doll
- Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Hiroyuki Koga
- Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Hirokazu Tsukaya
- Graduate School of Science, The University of Tokyo, Tokyo, Japan
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15
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Siqueira JA, Oliveira de Oliveira H, Nunes-Nesi A, Araújo WL. Guard cell regulation: pulling the strings behind the scenes. TRENDS IN PLANT SCIENCE 2021; 26:1093-1095. [PMID: 34303605 DOI: 10.1016/j.tplants.2021.07.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 07/01/2021] [Accepted: 07/07/2021] [Indexed: 06/13/2023]
Abstract
The precise regulation of stomata is critical to plant growth and development, especially under drought conditions. Two recent studies (Dou et al., Xu et al.) shed new light on stomata physiology in response to dynamic environmental conditions, revealing novel key mechanisms related to microtubule dynamics and energy sensing within the guard cells.
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Affiliation(s)
- João Antonio Siqueira
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900 Viçosa, MG, Brazil
| | | | - Adriano Nunes-Nesi
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900 Viçosa, MG, Brazil
| | - Wagner L Araújo
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900 Viçosa, MG, Brazil.
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16
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Anderson JT, Jameel MI, Geber MA. Selection favors adaptive plasticity in a long-term reciprocal transplant experiment. Evolution 2021; 75:1711-1726. [PMID: 34076252 DOI: 10.1111/evo.14280] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 05/06/2021] [Accepted: 05/17/2021] [Indexed: 12/28/2022]
Abstract
Spatial and temporal environmental variation can favor the evolution of adaptive phenotypic plasticity, such that genotypes alter their phenotypes in response to local conditions to maintain fitness across heterogeneous landscapes. When individuals show greater fitness in one habitat than another, asymmetric migration can restrict adaptation to the lower quality environment. In these cases, selection is predicted to favor traits that enhance fitness in the higher-quality (source) habitat at the expense of fitness in the marginal (sink) habitat. Here, we test whether plasticity is adaptive in a system regulated by demographic source-sink dynamics. Vaccinium elliottii (Ericaceae) occurs in dry upland and flood-prone bottomland forests throughout the southeastern United States, but has larger populations and higher average individual fitness in upland sites. We conducted a multi-year field experiment to evaluate whether plasticity in foliar morphology increases survival and lifespan. Both across and within habitats, selection favored plasticity in specific leaf area, stomatal density, and leaf size. Stabilizing selection acted on plasticity in stomatal density within habitats, suggesting that extreme levels of plasticity are disadvantageous. Thus, even in systems driven by source-sink dynamics, temporal and spatial variation in conditions across the landscape and within habitat types can favor the evolution of plasticity.
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Affiliation(s)
- Jill T Anderson
- Department of Genetics and Odum School of Ecology, University of Georgia, Athens, Georgia, 30602
| | - M Inam Jameel
- Department of Genetics and Odum School of Ecology, University of Georgia, Athens, Georgia, 30602
| | - Monica A Geber
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York, 14850
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17
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Neto-Bradley BM, Muir CD, Whitton J, Pennell MW. Phylogenetic history of vascular plant metabolism revealed using a macroevolutionary common garden. Proc Biol Sci 2021; 288:20210605. [PMID: 34074123 PMCID: PMC8170189 DOI: 10.1098/rspb.2021.0605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 05/07/2021] [Indexed: 11/12/2022] Open
Abstract
While the fundamental biophysics of C3 photosynthesis is highly conserved across plants, substantial leaf structural and enzymatic variation translates into variability in rates of carbon assimilation. Although this variation is well documented, it remains poorly understood how photosynthetic rates evolve, and whether macroevolutionary changes are related to the evolution of leaf morphology and biochemistry. A substantial challenge in large-scale comparative studies is disentangling evolutionary adaptation from environmental acclimation. We overcome this by using a 'macroevolutionary common garden' approach in which we measured metabolic traits (Jmax and Vcmax) from 111 phylogenetically diverse species in a shared environment. We find substantial phylogenetic signal in these traits at moderate phylogenetic timescales, but this signal dissipates quickly at deeper scales. Morphological traits exhibit phylogenetic signal over much deeper timescales, suggesting that these are less evolutionarily constrained than metabolic traits. Furthermore, while morphological and biochemical traits (LMA, Narea and Carea) are weakly predictive of Jmax and Vcmax, evolutionary changes in these traits are mostly decoupled from changes in metabolic traits. This lack of tight evolutionary coupling implies that it may be incorrect to use changes in these functional traits in response to global change to infer that photosynthetic strategy is also evolving.
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Affiliation(s)
- Barbara M. Neto-Bradley
- Department of Botany, University of British Columbia, Vancouver, Canada
- Biodiversity Research Centre, University of British Columbia, Vancouver, Canada
| | | | - Jeannette Whitton
- Department of Botany, University of British Columbia, Vancouver, Canada
- Biodiversity Research Centre, University of British Columbia, Vancouver, Canada
| | - Matthew W. Pennell
- Biodiversity Research Centre, University of British Columbia, Vancouver, Canada
- Department of Zoology, University of British Columbia, Vancouver, Canada
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18
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Haworth M, Marino G, Loreto F, Centritto M. Integrating stomatal physiology and morphology: evolution of stomatal control and development of future crops. Oecologia 2021; 197:867-883. [PMID: 33515295 PMCID: PMC8591009 DOI: 10.1007/s00442-021-04857-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 01/11/2021] [Indexed: 11/29/2022]
Abstract
Stomata are central players in the hydrological and carbon cycles, regulating the uptake of carbon dioxide (CO2) for photosynthesis and transpirative loss of water (H2O) between plants and the atmosphere. The necessity to balance water-loss and CO2-uptake has played a key role in the evolution of plants, and is increasingly important in a hotter and drier world. The conductance of CO2 and water vapour across the leaf surface is determined by epidermal and stomatal morphology (the number, size, and spacing of stomatal pores) and stomatal physiology (the regulation of stomatal pore aperture in response to environmental conditions). The proportion of the epidermis allocated to stomata and the evolution of amphistomaty are linked to the physiological function of stomata. Moreover, the relationship between stomatal density and [CO2] is mediated by physiological stomatal behaviour; species with less responsive stomata to light and [CO2] are most likely to adjust stomatal initiation. These differences in the sensitivity of the stomatal density—[CO2] relationship between species influence the efficacy of the ‘stomatal method’ that is widely used to infer the palaeo-atmospheric [CO2] in which fossil leaves developed. Many studies have investigated stomatal physiology or morphology in isolation, which may result in the loss of the ‘overall picture’ as these traits operate in a coordinated manner to produce distinct mechanisms for stomatal control. Consideration of the interaction between stomatal morphology and physiology is critical to our understanding of plant evolutionary history, plant responses to on-going climate change and the production of more efficient and climate-resilient food and bio-fuel crops.
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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, Agriculture and Food Sciences (CNR-DiSBA), National Research Council of Italy, Rome, Italy
- 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 Center "Hypatia of Alexandria", Research Center Metapontum Agrobios, Metaponto, Italy
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19
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Liu C, Li Y, Xu L, Li M, Wang J, Yan P, He N. Stomatal Arrangement Pattern: A New Direction to Explore Plant Adaptation and Evolution. FRONTIERS IN PLANT SCIENCE 2021; 12:655255. [PMID: 33995451 PMCID: PMC8120035 DOI: 10.3389/fpls.2021.655255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 04/06/2021] [Indexed: 05/02/2023]
Abstract
The arrangement patterns of stomata on the leaf surface influence water loss and CO2 uptake via transportation and diffusion between stomata, the sites of photosynthesis, and vasculature. However, the quantification of such patterns remains unclear. Based on the distance between stomata, we developed three independent indices to quantify stomatal arrangement pattern (SAP). "Stomatal evenness" was used to quantify the regularity of the distribution of stomata based on a minimum spanning tree, "stomatal divergence" described the divergence in the distribution of stomata based on their distances from their center of gravity, and "stomatal aggregation" was used to quantitatively distinguish the SAP as clustered, random, or regularly distributed based on the nearest-neighbor distances. These three indices address the shortcoming of stomatal density that only describes "abundance" and may, collectively, have a better capacity to explore crop development, plant adaptation and evolution, and potentially ultimately enable a more accurate reconstruction of the palaeoclimate.
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Affiliation(s)
- Congcong Liu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Ying Li
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Li Xu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Mingxu Li
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Jianming Wang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Pu Yan
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Nianpeng He
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Vegetation Ecology of Ministry of Education, Institute of Grassland Science, Northeast Normal University, Changchun, China
- *Correspondence: Nianpeng He,
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20
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Xiong D, Flexas J. From one side to two sides: the effects of stomatal distribution on photosynthesis. THE NEW PHYTOLOGIST 2020; 228:1754-1766. [PMID: 32652573 DOI: 10.1111/nph.16801] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 07/02/2020] [Indexed: 06/11/2023]
Abstract
The functions of stomata have been studied for a long time; however, a clear understanding of the influences of stomatal distribution on photosynthesis, especially the CO2 diffusion, is still unclear. Here, we investigated the stomatal morphology, distribution on leaf surfaces, vein traits and gas exchange parameters of 61 species, of which 29 were amphistomatous, spanning 32 families. Photosynthesis (A) was tightly coupled with operational stomatal conductance (gs ) and mesophyll conductance (gm ) regardless of whether phylogenetic relationships were accounted for. Although the enhancement of gs from ferns and gymnosperms to angiosperms could largely be explained by the increase in leaf vein density (VLA) and stomatal density (SD), the gs was decoupled from VLA and SD across angiosperm species. Instead, A in angiosperms was further influenced by the allocation of stomatal pores on leaf surfaces, which dramatically increased gs and gm . Moreover, the ratio of gs to anatomically based maximum gs was, on average, 0.12 across species. Our results show that the shift of stomatal pores from one leaf side to both sides played an important role in regulating CO2 diffusion via both stomata and mesophyll tissues. Modifications of stomata distribution have potential as a functional trait for photosynthesis improvement.
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Affiliation(s)
- Dongliang Xiong
- National Key Laboratory of Crop Genetic Improvement, MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Jaume Flexas
- Research Group on Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears/Instituto de Investigaciones Agroambientales y de Economía del Agua (INAGEA), Carretera de Valldemossa Km 7.5, Palma de Mallorca, Illes Balears, 07121, Spain
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21
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Muir CD. A Stomatal Model of Anatomical Tradeoffs Between Gas Exchange and Pathogen Colonization. FRONTIERS IN PLANT SCIENCE 2020; 11:518991. [PMID: 33193466 PMCID: PMC7658178 DOI: 10.3389/fpls.2020.518991] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 10/01/2020] [Indexed: 06/11/2023]
Abstract
Stomatal pores control leaf gas exchange and are one route for infection of internal plant tissues by many foliar pathogens, setting up the potential for tradeoffs between photosynthesis and pathogen colonization. Anatomical shifts to lower stomatal density and/or size may also limit pathogen colonization, but such developmental changes could permanently reduce the gas exchange capacity for the life of the leaf. I developed and analyzed a spatially explicit model of pathogen colonization on the leaf as a function of stomatal size and density, anatomical traits which partially determine maximum rates of gas exchange. The model predicts greater stomatal size or density increases the probability of colonization, but the effect is most pronounced when the fraction of leaf surface covered by stomata is low. I also derived scaling relationships between stomatal size and density that preserves a given probability of colonization. These scaling relationships set up a potential anatomical conflict between limiting pathogen colonization and minimizing the fraction of leaf surface covered by stomata. Although a connection between gas exchange and pathogen defense has been suggested empirically, this is the first mathematical model connecting gas exchange and pathogen defense via stomatal anatomy. A limitation of the model is that it does not include variation in innate immunity and stomatal closure in response to pathogens. Nevertheless, the model makes predictions that can be tested with experiments and may explain variation in stomatal size and density among plants. The model is generalizable to many types of pathogens, but lacks significant biological realism that may be needed for precise predictions.
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22
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McKown KH, Bergmann DC. Stomatal development in the grasses: lessons from models and crops (and crop models). THE NEW PHYTOLOGIST 2020; 227:1636-1648. [PMID: 31985072 DOI: 10.1111/nph.16450] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 01/08/2020] [Indexed: 05/24/2023]
Abstract
When plants emerged from their aquatic origins to colonise land, they needed to avoid desiccation while still enabling gas and water exchange with the environment. The solution was the development of a waxy cuticle interrupted by epidermal pores, known as stomata. Despite the importance of stomata in plant physiology and their contribution to global water and carbon cycles, our knowledge of the genetic basis of stomatal development is limited mostly to the model dicot, Arabidopsis thaliana. This limitation is particularly troublesome when evaluating grasses, whose members represent our most agriculturally significant crops. Grass stomatal development follows a trajectory strikingly different from Arabidopsis and their uniquely shaped four-celled stomatal complexes are especially responsive to environmental inputs. Thus, understanding the development and regulation of these efficient complexes is of particular interest for the purposes of crop engineering. This review focuses on genetic regulation of grass stomatal development and prospects for the future, highlighting discoveries enabled by parallel comparative investigations in cereal crops and related genetic model species such as Brachypodium distachyon.
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Affiliation(s)
- Katelyn H McKown
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Dominique C Bergmann
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
- Howard Hughes Medical Institute, Stanford, CA, 94305, USA
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23
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Sadok W, Lopez JR, Zhang Y, Tamang BG, Muehlbauer GJ. Sheathing the blade: Significant contribution of sheaths to daytime and nighttime gas exchange in a grass crop. PLANT, CELL & ENVIRONMENT 2020; 43:1844-1861. [PMID: 32459028 DOI: 10.1111/pce.13808] [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: 12/19/2019] [Revised: 03/31/2020] [Accepted: 05/18/2020] [Indexed: 06/11/2023]
Abstract
Despite representing a sizeable fraction of the canopy, very little is known about leaf sheath gas exchange in grasses. Specifically, estimates of sheath stomatal conductance, transpiration and photosynthesis along with their responses to light, CO2 and vapour pressure deficit (VPD) are unknown. Furthermore, the anatomical basis of these responses is poorly documented. Here, using barley as a model system, and combining leaf-level gas exchange, whole-plant gravimetric measurements, transpiration inhibitors, anatomical observations, and biophysical modelling, we found that sheath and blade stomatal conductance and transpiration were similar, especially at low light, in addition to being genotypically variable. Thanks to high abaxial stomata densities and surface areas nearly half those of the blades, sheaths accounted for up to 17% of the daily whole-plant water use, which -surprisingly- increased to 45% during the nighttime. Sheath photosynthesis was on average 17-25% that of the blade and was associated with lower water use efficiency. Finally, sheaths responded differently to the environment, exhibiting a lack of response to CO2 but a strong sensitivity to VPD. Overall, these results suggest a key involvement of sheaths in feedback loops between canopy architecture and gas exchange with potentially significant implications on adaptation to current and future climates in grasses.
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Affiliation(s)
- Walid Sadok
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, Minnesota, USA
| | - Jose R Lopez
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, Minnesota, USA
| | - Yangyang Zhang
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, Minnesota, USA
- Department of Grassland Science, China Agricultural University, Beijing, China
| | - Bishal G Tamang
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, Minnesota, USA
| | - Gary J Muehlbauer
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, Minnesota, USA
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24
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Richardson F, Jordan GJ, Brodribb TJ. Leaf hydraulic conductance is linked to leaf symmetry in bifacial, amphistomatic leaves of sunflower. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:2808-2816. [PMID: 31970417 PMCID: PMC7210757 DOI: 10.1093/jxb/eraa035] [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: 06/04/2019] [Accepted: 01/21/2020] [Indexed: 05/14/2023]
Abstract
The hydraulic implications of stomatal positioning across leaf surfaces and the impact on internal water flow through amphistomatic leaves are not currently well understood. Amphistomaty potentially provides hydraulic efficiencies if the majority of hydraulic resistance in the leaf exists outside the xylem in the mesophyll. Such a scenario would mean that the same xylem network could equally supply a hypostomatic or amphistomatic leaf. Here we examine leaves of Helianthus annuus to determine whether amphistomaty in this species is associated with higher hydraulic efficiency compared with hypostomatic leaves. We identified asymmetry in the positioning of minor veins which were significantly closer to the abaxial than the adaxial leaf surface, combined with lower Kleaf when transpiration was driven through the adaxial rather than the abaxial surface. We also identified a degree of coordination in stomatal behaviour driven by leaf hydraulics, where the hydraulic conditions experienced by an individual leaf surface affected the stomatal behaviour on the opposite surface. We found no advantage to amphistomaty based on efficiencies in construction costs of the venous system, represented by vein density:stomatal density, only limited hydraulic independence between leaf surfaces. These results suggest that amphistomaty does not substantially increase whole-leaf hydraulic efficiency.
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Affiliation(s)
- Freya Richardson
- School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia
| | - Gregory J Jordan
- School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia
| | - Timothy J Brodribb
- School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia
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25
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Hager HA, Ryan GD, Newman JA. Effects of elevated CO 2 on competition between native and invasive grasses. Oecologia 2020; 192:1099-1110. [PMID: 32253494 DOI: 10.1007/s00442-020-04636-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 03/30/2020] [Indexed: 11/24/2022]
Abstract
Elevated atmospheric CO2 concentration increases the performance of invasive plants relative to natives when grown in monoculture, but it is unclear how that will affect the relative competitive abilities per se of invasive and native grasses grown together. We tested competitive outcomes for four native and four invasive perennial C3 and C4 grasses under ambient (390 ppm) and elevated (700 or 1000 ppm) CO2 concentrations in the greenhouse with non-limiting water and nutrients. We predicted that elevated CO2 would increase the competitive suppression of native grasses by invasive grasses. To test this, we determined the relative interaction intensity of biomass allocation for natives grown alone vs. those grown in native-invasive species pairs. We also measured photosynthetic traits that contribute to plant invasiveness and may be affected by elevated CO2 concentrations for species pairs in mixture to determine native-invasive relative performance. We found no effect of CO2 for the aboveground biomass and tiller production measures of interaction intensity or for relative performance for most of the measured photosynthetic traits. In competition, the invaders nearly always outperform natives in biomass and tiller production, regardless of CO2 level. The results suggest that increasing CO2 concentration alone has little effect on grass competitive outcomes under controlled conditions.
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Affiliation(s)
- Heather A Hager
- School of Environmental Sciences, University of Guelph, Guelph, ON, N1G 2W1, Canada. .,Department of Biology, Wilfrid Laurier University, Waterloo, ON, N2L 3C5, Canada.
| | - Geraldine D Ryan
- School of Environmental Sciences, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - Jonathan A Newman
- School of Environmental Sciences, University of Guelph, Guelph, ON, N1G 2W1, Canada.,Department of Biology, Wilfrid Laurier University, Waterloo, ON, N2L 3C5, Canada
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Yoko ZG, Volk KL, Dochtermann NA, Hamilton JA. The importance of quantitative trait differentiation in restoration: landscape heterogeneity and functional traits inform seed transfer guidelines. AOB PLANTS 2020; 12:plaa009. [PMID: 32257091 PMCID: PMC7112727 DOI: 10.1093/aobpla/plaa009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 02/28/2020] [Indexed: 06/01/2023]
Abstract
For widely distributed species, understanding the scale over which genetic variation correlates to landscape structure and composition is critical. Particularly within the context of restoration, the evolution of genetic differences may impact success if seeds are maladapted to the restoration environment. In this study, we used Geum triflorum to quantify the scale over which genetic differences for quantitative traits important to adaptation have evolved, comparing the proportion of variance attributed to broad regional- and local population-level effects. Geum triflorum is a widely distributed species spanning a range of environments, including alvar and prairie habitats, which have extreme regional differences in soil-moisture availability. Alvar habitats are regions of thin soil over limestone that experience substantial seasonal variation in water availability, from flooding to desiccation annually. This contrasts with prairie habitats, whose deeper soils mitigate irregular flood-desiccation cycles. Using a common garden experiment, we evaluated 15 traits broadly grouped into three trait classes: resource allocation, stomatal characteristics, and leaf morphological traits for individuals sourced from prairie and alvar environments. We quantified the proportion of trait variance explained by regional- and population-scale effects and compared the proportion of regional- and population-trait variances explained across trait classes. Significant regional differentiation was observed for the majority of quantitative traits; however, population-scale effects were equal or greater than regional effects, suggesting that important genetic differences may have evolved across the finer population scale. Stomatal and resource allocation trait classes exhibited substantial regional differentiation relative to morphological traits, which may indicate increased strength of selection for stomatal and resource allocation traits relative to morphological traits. These patterns point towards the value in considering the scale over which genetic differences may have evolved for widely distributed species and identify different functional trait classes that may be valuable in establishing seed transfer guidelines.
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Affiliation(s)
- Zebadiah G Yoko
- Department of Biological Sciences, North Dakota State University, Fargo, ND, USA
| | - Kate L Volk
- Department of Biological Sciences, North Dakota State University, Fargo, ND, USA
| | - Ned A Dochtermann
- Department of Biological Sciences, North Dakota State University, Fargo, ND, USA
| | - Jill A Hamilton
- Department of Biological Sciences, North Dakota State University, Fargo, ND, USA
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Harrison EL, Arce Cubas L, Gray JE, Hepworth C. The influence of stomatal morphology and distribution on photosynthetic gas exchange. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:768-779. [PMID: 31583771 PMCID: PMC7065165 DOI: 10.1111/tpj.14560] [Citation(s) in RCA: 78] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 09/25/2019] [Accepted: 10/03/2019] [Indexed: 05/18/2023]
Abstract
The intricate and interconnecting reactions of C3 photosynthesis are often limited by one of two fundamental processes: the conversion of solar energy into chemical energy, or the diffusion of CO2 from the atmosphere through the stomata, and ultimately into the chloroplast. In this review, we explore how the contributions of stomatal morphology and distribution can affect photosynthesis, through changes in gaseous exchange. The factors driving this relationship are considered, and recent results from studies investigating the effects of stomatal shape, size, density and patterning on photosynthesis are discussed. We suggest that the interplay between stomatal gaseous exchange and photosynthesis is complex, and that a disconnect often exists between the rates of CO2 diffusion and photosynthetic carbon fixation. The mechanisms that allow for substantial reductions in maximum stomatal conductance without affecting photosynthesis are highly dependent on environmental factors, such as light intensity, and could be exploited to improve crop performance.
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Affiliation(s)
- Emily L. Harrison
- Department of Molecular Biology and BiotechnologyUniversity of Sheffield, Western BankSheffieldUK
| | - Lucia Arce Cubas
- Department of Molecular Biology and BiotechnologyUniversity of Sheffield, Western BankSheffieldUK
| | - Julie E. Gray
- Department of Molecular Biology and BiotechnologyUniversity of Sheffield, Western BankSheffieldUK
| | - Christopher Hepworth
- Department of Molecular Biology and BiotechnologyUniversity of Sheffield, Western BankSheffieldUK
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28
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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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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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30
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Muir CD. tealeaves: an R package for modelling leaf temperature using energy budgets. AOB PLANTS 2019; 11:plz054. [PMID: 31844509 PMCID: PMC6899345 DOI: 10.1093/aobpla/plz054] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 09/21/2019] [Indexed: 05/29/2023]
Abstract
Plants must regulate leaf temperature to optimize photosynthesis, control water loss and prevent damage caused by overheating or freezing. Physical models of leaf energy budgets calculate the energy fluxes and leaf temperatures for a given set leaf and environmental parameters. These models can provide deep insight into the variation in leaf form and function, but there are few computational tools available to use these models. Here I introduce a new R package called tealeaves to make complex leaf energy budget models accessible to a broader array of plant scientists. This package enables novice users to start modelling leaf energy budgets quickly while allowing experts to customize their parameter settings. The code is open source, freely available and readily integrates with other R tools for scientific computing. This paper describes the current functionality of tealeaves, but new features will be added in future releases. This software tool will advance new research on leaf thermal physiology to advance our understanding of basic and applied plant science.
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McKown AD, Klápště J, Guy RD, Corea ORA, Fritsche S, Ehlting J, El-Kassaby YA, Mansfield SD. A role for SPEECHLESS in the integration of leaf stomatal patterning with the growth vs disease trade-off in poplar. THE NEW PHYTOLOGIST 2019; 223:1888-1903. [PMID: 31081152 DOI: 10.1111/nph.15911] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 04/29/2019] [Indexed: 05/08/2023]
Abstract
Occurrence of stomata on both leaf surfaces (amphistomaty) promotes higher stomatal conductance and photosynthesis while simultaneously increasing exposure to potential disease agents in black cottonwood (Populus trichocarpa). A genome-wide association study (GWAS) with 2.2M single nucleotide polymorphisms generated through whole-genome sequencing found 280 loci associated with variation in adaxial stomatal traits, implicating genes regulating stomatal development and behavior. Strikingly, numerous loci regulating plant growth and response to biotic and abiotic stresses were also identified. The most significant locus was a poplar homologue of SPEECHLESS (PtSPCH1). Individuals possessing PtSPCH1 alleles associated with greater adaxial stomatal density originated primarily from environments with shorter growing seasons (e.g. northern latitudes, high elevations) or with less precipitation. PtSPCH1 was expressed in developing leaves but not developing stem xylem. In developing leaves, RNA sequencing showed patterns of coordinated expression between PtSPCH1 and other GWAS-identified genes. The breadth of our GWAS results suggests that the evolution of amphistomaty is part of a larger, complex response in plants. Suites of genes underpin this response, retrieved through genetic association to adaxial stomata, and show coordinated expression during development. We propose that the occurrence of amphistomaty in P. trichocarpa involves PtSPCH1 and reflects selection for supporting rapid growth over investment in immunity.
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Affiliation(s)
- Athena D McKown
- Department of Forest and Conservation Sciences, Faculty of Forestry, Forest Sciences Centre, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Jaroslav Klápště
- Department of Forest and Conservation Sciences, Faculty of Forestry, Forest Sciences Centre, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
- Department of Genetics and Physiology of Forest Trees, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Prague, 165 21, Czech Republic
- Scion (New Zealand Forest Research Institute Ltd), Whakarewarewa, Rotorua, 3046, New Zealand
| | - Robert D Guy
- Department of Forest and Conservation Sciences, Faculty of Forestry, Forest Sciences Centre, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Oliver R A Corea
- Department of Biology and Centre for Forest Biology, University of Victoria, Victoria, BC, V8W 3N5, Canada
| | - Steffi Fritsche
- Scion (New Zealand Forest Research Institute Ltd), Whakarewarewa, Rotorua, 3046, New Zealand
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Jürgen Ehlting
- Department of Biology and Centre for Forest Biology, University of Victoria, Victoria, BC, V8W 3N5, Canada
| | - Yousry A El-Kassaby
- Department of Forest and Conservation Sciences, Faculty of Forestry, Forest Sciences Centre, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Shawn D Mansfield
- Department of Wood Science, Faculty of Forestry, Forest Sciences Centre, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
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32
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Muir CD. Is Amphistomy an Adaptation to High Light? Optimality Models of Stomatal Traits along Light Gradients. Integr Comp Biol 2019. [PMID: 31141118 DOI: 10.1101/601377] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023] Open
Abstract
Stomata regulate the supply of CO2 for photosynthesis and the rate of water loss out of the leaf. The presence of stomata on both leaf surfaces, termed amphistomy, increases photosynthetic rate, is common in plants from high light habitats, and rare otherwise. In this study I use optimality models based on leaf energy budget and photosynthetic models to ask why amphistomy is common in high light habitats. I developed an R package leafoptimizer to solve for stomatal traits that optimally balance carbon gain with water loss in a given environment. The model predicts that amphistomy is common in high light because its marginal effect on carbon gain is greater than in the shade, but only if the costs of amphistomy are also lower under high light than in the shade. More generally, covariation between costs and benefits may explain why stomatal and other traits form discrete phenotypic clusters.
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33
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Šantrůček J, Schreiber L, Macková J, Vráblová M, Květoň J, Macek P, Neuwirthová J. Partitioning of mesophyll conductance for CO 2 into intercellular and cellular components using carbon isotope composition of cuticles from opposite leaf sides. PHOTOSYNTHESIS RESEARCH 2019; 141:33-51. [PMID: 30806882 DOI: 10.1007/s11120-019-00628-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 02/14/2019] [Indexed: 06/09/2023]
Abstract
We suggest a new technique for estimating the relative drawdown of CO2 concentration (c) in the intercellular air space (IAS) across hypostomatous leaves (expressed as the ratio cd/cb, where the indexes d and b denote the adaxial and abaxial edges, respectively, of IAS), based on the carbon isotope composition (δ13C) of leaf cuticular membranes (CMs), cuticular waxes (WXs) or epicuticular waxes (EWXs) isolated from opposite leaf sides. The relative drawdown in the intracellular liquid phase (i.e., the ratio cc/cbd, where cc and cbd stand for mean CO2 concentrations in chloroplasts and in the IAS), the fraction of intercellular resistance in the total mesophyll resistance (rIAS/rm), leaf thickness, and leaf mass per area (LMA) were also assessed. We show in a conceptual model that the upper (adaxial) side of a hypostomatous leaf should be enriched in 13C compared to the lower (abaxial) side. CM, WX, and/or EWX isolated from 40 hypostomatous C3 species were 13C depleted relative to bulk leaf tissue by 2.01-2.85‰. The difference in δ13C between the abaxial and adaxial leaf sides (δ13CAB - 13CAD, Δb-d), ranged from - 2.22 to + 0.71‰ (- 0.09 ± 0.54‰, mean ± SD) in CM and from - 7.95 to 0.89‰ (- 1.17 ± 1.40‰) in WX. In contrast, two tested amphistomatous species showed no significant Δb-d difference in WX. Δb-d correlated negatively with LMA and leaf thickness of hypostomatous leaves, which indicates that the mesophyll air space imposes a non-negligible resistance to CO2 diffusion. δ13C of EWX and 30-C aldehyde in WX reveal a stronger CO2 drawdown than bulk WX or CM. Mean values of cd/cb and cc/cbd were 0.90 ± 0.12 and 0.66 ± 0.11, respectively, across 14 investigated species in which wax was isolated and analyzed. The diffusion resistance of IAS contributed 20 ± 14% to total mesophyll resistance and reflects species-specific and environmentally-induced differences in leaf functional anatomy.
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Affiliation(s)
- J Šantrůček
- Faculty of Science, University of South Bohemia, Branišovská 31, 37005, Ceske Budejovice, Czech Republic.
| | - L Schreiber
- Institute for Cellular & Molecular Botany - IZMB, University of Bonn, Kirschallee 1, 53115, Bonn, Germany
| | - J Macková
- Biology Centre ASCR, Institute of Soil Biology, Na Sádkách 702/7, 37005, Ceske Budejovice, Czech Republic
| | - M Vráblová
- Faculty of Science, University of South Bohemia, Branišovská 31, 37005, Ceske Budejovice, Czech Republic
- Institute of Environmental Technology, VSB - Technical University of Ostrava, 17. listopadu 15, 70833, Ostrava, Czech Republic
| | - J Květoň
- Faculty of Science, University of South Bohemia, Branišovská 31, 37005, Ceske Budejovice, Czech Republic
- Institute of Experimental Botany, Academy of Sciences of the Czech Republic, 16502, Prague, Czech Republic
| | - P Macek
- Faculty of Science, University of South Bohemia, Branišovská 31, 37005, Ceske Budejovice, Czech Republic
- Biology Centre ASCR, Institute of Soil Biology, Na Sádkách 702/7, 37005, Ceske Budejovice, Czech Republic
| | - J Neuwirthová
- Faculty of Science, University of South Bohemia, Branišovská 31, 37005, Ceske Budejovice, Czech Republic
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Muir CD. Is Amphistomy an Adaptation to High Light? Optimality Models of Stomatal Traits along Light Gradients. Integr Comp Biol 2019; 59:571-584. [DOI: 10.1093/icb/icz085] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
AbstractStomata regulate the supply of CO2 for photosynthesis and the rate of water loss out of the leaf. The presence of stomata on both leaf surfaces, termed amphistomy, increases photosynthetic rate, is common in plants from high light habitats, and rare otherwise. In this study I use optimality models based on leaf energy budget and photosynthetic models to ask why amphistomy is common in high light habitats. I developed an R package leafoptimizer to solve for stomatal traits that optimally balance carbon gain with water loss in a given environment. The model predicts that amphistomy is common in high light because its marginal effect on carbon gain is greater than in the shade, but only if the costs of amphistomy are also lower under high light than in the shade. More generally, covariation between costs and benefits may explain why stomatal and other traits form discrete phenotypic clusters.
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35
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Shelef O, Summerfield L, Lev-Yadun S, Villamarin-Cortez S, Sadeh R, Herrmann I, Rachmilevitch S. Thermal Benefits From White Variegation of Silybum marianum Leaves. FRONTIERS IN PLANT SCIENCE 2019; 10:688. [PMID: 31178888 PMCID: PMC6543541 DOI: 10.3389/fpls.2019.00688] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Accepted: 05/07/2019] [Indexed: 05/24/2023]
Abstract
Leaves of the spiny winter annual Silybum marianum express white patches (variegation) that can cover significant surface areas, the outcome of air spaces formed between the epidermis and the green chlorenchyma. We asked: (1) what characterizes the white patches in S. marianum and what differs them from green patches? (2) Do white patches differ from green patches in photosynthetic efficiency under lower temperatures? We predicted that the air spaces in white patches have physiological benefits, elevating photosynthetic rates under low temperatures. To test our hypotheses we used both a variegated wild type and entirely green mutants. We grew the plants under moderate temperatures (20°C/10°C d/n) and compared them to plants grown under lower temperatures (15°C/5°C d/n). The developed plants were exposed to different temperatures for 1 h and their photosynthetic activity was measured. In addition, we compared in green vs. white patches, the reflectance spectra, patch structure, chlorophyll and dehydrin content, stomatal structure, plant growth, and leaf temperature. White patches were not significantly different from green patches in their biochemistry and photosynthesis. However, under lower temperatures, variegated wild-type leaves were significantly warmer than all-green mutants - possible explanations for that are discussed These findings support our hypothesis, that white variegation of S. marianum leaves has a physiological role, elevating leaf temperature during cold winter days.
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Affiliation(s)
- Oren Shelef
- Department of Natural Resources, Institute of Plant Sciences, Agricultural Research Organization, Rishon LeZion, Israel
| | - Liron Summerfield
- French Associates Institute for Agriculture and Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Beersheba, Israel
| | - Simcha Lev-Yadun
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa–Oranim, Tivon, Israel
| | | | - Roy Sadeh
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Ittai Herrmann
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Shimon Rachmilevitch
- French Associates Institute for Agriculture and Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Beersheba, Israel
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Drake PL, de Boer HJ, Schymanski SJ, Veneklaas EJ. Two sides to every leaf: water and CO 2 transport in hypostomatous and amphistomatous leaves. THE NEW PHYTOLOGIST 2019; 222:1179-1187. [PMID: 30570766 DOI: 10.1111/nph.15652] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 12/11/2018] [Indexed: 06/09/2023]
Abstract
Leaves with stomata on both upper and lower surfaces, termed amphistomatous, are relatively rare compared with hypostomatous leaves with stomata only on the lower surface. Amphistomaty occurs predominantly in fast-growing herbaceous annuals and in slow-growing perennial shrubs and trees. In this paper, we present the current understanding and hypotheses on the costs and benefits of amphistomaty related to water and CO2 transport in contrasting leaf morphologies. First, there is no evidence that amphistomatous species achieve higher stomatal densities on a projected leaf area basis than hypostomatous species, but two-sided gas exchange is less limited by boundary layer effects. Second, amphistomaty may provide a specific advantage in thick leaves by shortening the pathway for CO2 transport between the atmosphere and the chloroplasts. In thin leaves of fast-growing herbaceous annuals, in which both the adaxial and abaxial pathways are already short, amphistomaty enhances leaf-atmosphere gas-exchange capacity. Third, amphistomaty may help to optimise the leaf-interior water status for CO2 transport by reducing temperature gradients and so preventing the condensation of water that could limit CO2 diffusion. Fourth, a potential cost of amphistomaty is the need for additional investments in leaf water transport tissue to balance the water loss through the adaxial surface.
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Affiliation(s)
- Paul L Drake
- School of Biological Sciences, The University of Western Australia, 6009, Crawley, WA, Australia
| | - Hugo J de Boer
- Department of Environmental Sciences, Utrecht University, 3584 CS, Utrecht, the Netherlands
| | - Stanislaus J Schymanski
- Department of Environmental Systems Sciences, ETH Zurich, 8092, Zurich, Switzerland
- Department of Environmental Research and Innovation, Luxembourg Institute of Science and Technology, 4362, Esch-sur-Alzette, Luxembourg
| | - Erik J Veneklaas
- School of Biological Sciences, The University of Western Australia, 6009, Crawley, WA, Australia
- School of Agriculture and Environment, The University of Western Australia, 6009, Crawley, WA, Australia
- Institute of Agriculture, The University of Western Australia, 6009, Crawley, WA, Australia
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37
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Muir CD. Light and growth form interact to shape stomatal ratio among British angiosperms. THE NEW PHYTOLOGIST 2018; 218:242-252. [PMID: 29288622 DOI: 10.1111/nph.14956] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Accepted: 11/10/2017] [Indexed: 05/02/2023]
Abstract
In most plants, stomata are located only on the abaxial leaf surface (hypostomy), but many plants have stomata on both surfaces (amphistomy). High light and herbaceous growth form have been hypothesized to favor amphistomy, but these hypotheses have not been rigorously tested together using phylogenetic comparative methods. I leveraged a large dataset including stomatal ratio, Ellenberg light indicator value, growth form and phylogenetic relationships for 372 species of British angiosperms. I used phylogenetic comparative methods to test how light and/or growth form influence stomatal ratio and density. High light and herbaceous growth form are correlated with amphistomy, as predicted, but they also interact; the effect of light is pronounced in therophytes (annuals) and perennial herbs, but muted in phanerophytes (shrubs and trees). Furthermore, amphistomy and stomatal density evolve together in response to light. Comparative analyses of British angiosperms reveal two major insights. First, light and growth form interact to shape stomatal ratio; amphistomy is common under high light, but mostly for herbs. Second, coordinated evolution of adaxial stomatal density and light tolerance indicates that amphistomy helps to optimally balance light acquisition with gas exchange. Stomatal ratio may have potential as a functional trait for paleoecology and crop improvement.
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Affiliation(s)
- Christopher D Muir
- Biodiversity Research Centre and Botany Department, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
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38
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Chin ARO, Sillett SC. Leaf acclimation to light availability supports rapid growth in tall Picea sitchensis trees. TREE PHYSIOLOGY 2017; 37:1352-1366. [PMID: 28387871 DOI: 10.1093/treephys/tpx027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2016] [Accepted: 03/01/2017] [Indexed: 06/07/2023]
Abstract
Leaf-level anatomical variation is readily apparent within tall tree crowns, yet the relative importance of water and light availability in controlling this variation remains unclear. Sitka spruce (Picea sitchensis, (Bong.) Carr.) thrives in temperate rainforests of the Pacific Northwest, where it has historically reached heights >100 m, despite rarely living more than 400 years alongside redwoods that are five times older. We examined leaves of trees up to 97 m tall using a combination of transverse sections, longitudinal sections, epidermal imprints and whole-leaf measurements to explore the combined effects of water stress and light availability on leaf development in P. sitchensis. In contrast to the situation in tall Cupressaceae, light availability-not hydraulic limitation-is the primary ecological driver of leaf-level anatomical variation in P. sitchensis. While height-associated decreases in leaf length and mesoporosity are best explained by hydrostatic constraints on leaf elongation, the majority of anatomical traits we measured reflect acclimation to light availability, including increases in leaf width and vascular tissue areas in the brightest parts of the crown. Along with these changes, the appearance of abaxial stomata in the bright upper crown, and the arrangement of mesophyll in uniseriate, transverse plates-with radially arranged apoplastic pathways leading directly to stomata before bridging them with a V-shaped cell-may enhance gas exchange and hydraulic conductivity. This suite of leaf traits suggests an adaptive strategy that maximizes photosynthesis at the expense of water-stress tolerance. Anatomical investigations spanning the height gradient in tall tree crowns build our understanding of mechanisms underlying among-species variation in growth rates, life spans, and potential responses to climate change.
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Affiliation(s)
- Alana R O Chin
- Department of Natural Resources, American River College, 4700 College Oak Drive, Sacramento, CA 95841,USA
| | - Stephen C Sillett
- Department of Forestry and Wildland Resources, Humboldt State University, 1 Harpst Street, Arcata, CA 95521, USA
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Li L, Ma Z, Niinemets Ü, Guo D. Three Key Sub-leaf Modules and the Diversity of Leaf Designs. FRONTIERS IN PLANT SCIENCE 2017; 8:1542. [PMID: 28932233 PMCID: PMC5592238 DOI: 10.3389/fpls.2017.01542] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 08/23/2017] [Indexed: 05/29/2023]
Abstract
Earth harbors a highly diverse array of plant leaf forms. A well-known pattern linking diverse leaf forms with their photosynthetic function across species is the global leaf economics spectrum (LES). However, within homogeneous plant functional groups such as tropical woody angiosperms or temperate deciduous woody angiosperms, many species can share a similar position in the LES but differ in other vital leaf traits, and thus function differently under the given suite of environmental drivers. How diverse leaves differentiate from each other has yet to be fully explained. Here, we propose a new perspective for linking leaf structure and function by arguing that a leaf may be divided into three key sub-modules, the light capture module, the water-nutrient flow module and the gas exchange module. Each module consists of a set of leaf tissues corresponding to a certain resource acquisition function, and the combination and configuration of different modules may differ depending on overall leaf functioning in a given environment. This modularized-leaf perspective differs from the whole-leaf perspective used in leaf economics theory and may serve as a valuable tool for tracing the evolution of leaf form and function. This perspective also implies that the evolutionary direction of various leaf designs is not to optimize a single critical trait, but to optimize the combination of different traits to better adapt to the historical and current environments. Future studies examining how different modules are synchronized for overall leaf functioning should offer critical insights into the diversity of leaf designs worldwide.
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Affiliation(s)
- Le Li
- Center for Forest Ecosystem Studies and Qianyanzhou Ecological Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of SciencesBeijing, China
- College of Resources and Environment, University of Chinese Academy of SciencesBeijing, China
| | - Zeqing Ma
- Center for Forest Ecosystem Studies and Qianyanzhou Ecological Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of SciencesBeijing, China
| | - Ülo Niinemets
- Department of Plant Physiology, Institute of Agricultural and Environmental Sciences, Estonian University of Life SciencesTartu, Estonia
- Estonian Academy of SciencesTallinn, Estonia
| | - Dali Guo
- Center for Forest Ecosystem Studies and Qianyanzhou Ecological Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of SciencesBeijing, China
- College of Resources and Environment, University of Chinese Academy of SciencesBeijing, China
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Vráblová M, Vrábl D, Hronková M, Kubásek J, Šantrůček J. Stomatal function, density and pattern, and CO 2 assimilation in Arabidopsis thaliana tmm1 and sdd1-1 mutants. PLANT BIOLOGY (STUTTGART, GERMANY) 2017; 19:689-701. [PMID: 28453883 DOI: 10.1111/plb.12577] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Accepted: 04/25/2017] [Indexed: 05/15/2023]
Abstract
Stomata modulate the exchange of water and CO2 between plant and atmosphere. Although stomatal density is known to affect CO2 diffusion into the leaf and thus photosynthetic rate, the effect of stomatal density and patterning on CO2 assimilation is not fully understood. We used wild types Col-0 and C24 and stomatal mutants sdd1-1 and tmm1 of Arabidopsis thaliana, differing in stomatal density and pattern, to study the effects of these variations on both stomatal and mesophyll conductance and CO2 assimilation rate. Anatomical parameters of stomata, leaf temperature and carbon isotope discrimination were also assessed. Our results indicate that increased stomatal density enhanced stomatal conductance in sdd1-1 plants, with no effect on photosynthesis, due to both unchanged photosynthetic capacity and decreased mesophyll conductance. Clustering (abnormal patterning formed by clusters of two or more stomata) and a highly unequal distribution of stomata between the adaxial and abaxial leaf sides in tmm1 mutants also had no effect on photosynthesis. Except at very high stomatal densities, stomatal conductance and water loss were proportional to stomatal density. Stomatal formation in clusters reduced stomatal dynamics and their operational range as well as the efficiency of CO2 transport.
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Affiliation(s)
- M Vráblová
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
- Institute of Environmental Technology, VSB-TU Ostrava, Ostrava, Czech Republic
| | - D Vrábl
- Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - M Hronková
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
- Biology Centre of the Academy of Sciences of Czech Republic, Institute of Plant Molecular Biology, České Budějovice, Czech Republic
| | - J Kubásek
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - J Šantrůček
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
- Biology Centre of the Academy of Sciences of Czech Republic, Institute of Plant Molecular Biology, České Budějovice, Czech Republic
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Richardson F, Brodribb TJ, Jordan GJ. Amphistomatic leaf surfaces independently regulate gas exchange in response to variations in evaporative demand. TREE PHYSIOLOGY 2017; 37:869-878. [PMID: 28898992 DOI: 10.1093/treephys/tpx073] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Accepted: 05/31/2017] [Indexed: 06/07/2023]
Abstract
The occurrence of amphistomatic leaves (stomata on both surfaces) versus hypostomatic leaves (stomata limited to the lower or abaxial surface) has strong associations with environment. Amphistomy provides the advantage of higher conductance of CO2 for photosynthesis, however, unless the stomata on both leaf surfaces can be independently controlled in response to environmental cues, amphistomy may lead to inefficient gas exchange. While previous studies have found evidence that stomata can operate independently across and between surfaces of dorsiventral leaves, we investigate whether an independent stomatal response can be induced for isobilateral leaves by largely natural conditions. Here, we exposed surfaces of isobilateral, amphistomatic Eucalyptus globulus Labill. leaves to natural diurnal variation in differential evaporative demand, using leaf orientation to drive differences in irradiance and heat load on leaf surfaces. We identified preferential closure of stomata on the surface exposed to higher irradiation (and therefore evaporative demand) during the afternoon under natural conditions and similarly induced differential stomatal closure under experimental conditions in the laboratory. The differential response confirms that sufficient hydraulic isolation exists for independent stomatal response to occur between surfaces of amphistomatic, isobilateral leaves, and importantly, we show that natural conditions can induce surface-specific stomatal closure.
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Affiliation(s)
- Freya Richardson
- School of Biological Sciences, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Timothy J Brodribb
- School of Biological Sciences, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Gregory J Jordan
- School of Biological Sciences, University of Tasmania, Hobart, Tasmania 7001, Australia
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McElwain JC, Steinthorsdottir M. Paleoecology, Ploidy, Paleoatmospheric Composition, and Developmental Biology: A Review of the Multiple Uses of Fossil Stomata. PLANT PHYSIOLOGY 2017; 174:650-664. [PMID: 28495890 PMCID: PMC5462064 DOI: 10.1104/pp.17.00204] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 05/10/2017] [Indexed: 05/05/2023]
Affiliation(s)
- Jennifer C McElwain
- Earth Institute, O'Brien Centre for Science, and School of Biology and Environmental Science, University College Dublin, Belfield, Dublin 4, Ireland (J.C.M.);
- Department of Palaeobiology, Swedish Museum of Natural History, SE-104 05 Stockholm, Sweden (M.S.); and
- Bolin Centre for Climate Research, Stockholm University, SE-104 05 Stockholm, Sweden (M.S.)
| | - Margret Steinthorsdottir
- Earth Institute, O'Brien Centre for Science, and School of Biology and Environmental Science, University College Dublin, Belfield, Dublin 4, Ireland (J.C.M.)
- Department of Palaeobiology, Swedish Museum of Natural History, SE-104 05 Stockholm, Sweden (M.S.); and
- Bolin Centre for Climate Research, Stockholm University, SE-104 05 Stockholm, Sweden (M.S.)
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Becklin KM, Anderson JT, Gerhart LM, Wadgymar SM, Wessinger CA, Ward JK. Examining Plant Physiological Responses to Climate Change through an Evolutionary Lens. PLANT PHYSIOLOGY 2016; 172:635-649. [PMID: 27591186 PMCID: PMC5047093 DOI: 10.1104/pp.16.00793] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 08/29/2016] [Indexed: 05/10/2023]
Abstract
Integrating knowledge from physiological ecology, evolutionary biology, phylogenetics, and paleobiology provides novel insights into factors driving plant physiological responses to both past and future climate change.
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Affiliation(s)
- Katie M Becklin
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, Kansas 66045 (K.M.B., C.A.W., J.K.W.);Odum School of Ecology and Department of Genetics, University of Georgia, Athens, Georgia 30602 (J.T.A., S.M.W.); andGeography Department, Kansas State University, Manhattan, Kansas 66506 (L.M.G.)
| | - Jill T Anderson
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, Kansas 66045 (K.M.B., C.A.W., J.K.W.);Odum School of Ecology and Department of Genetics, University of Georgia, Athens, Georgia 30602 (J.T.A., S.M.W.); andGeography Department, Kansas State University, Manhattan, Kansas 66506 (L.M.G.)
| | - Laci M Gerhart
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, Kansas 66045 (K.M.B., C.A.W., J.K.W.);Odum School of Ecology and Department of Genetics, University of Georgia, Athens, Georgia 30602 (J.T.A., S.M.W.); andGeography Department, Kansas State University, Manhattan, Kansas 66506 (L.M.G.)
| | - Susana M Wadgymar
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, Kansas 66045 (K.M.B., C.A.W., J.K.W.);Odum School of Ecology and Department of Genetics, University of Georgia, Athens, Georgia 30602 (J.T.A., S.M.W.); andGeography Department, Kansas State University, Manhattan, Kansas 66506 (L.M.G.)
| | - Carolyn A Wessinger
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, Kansas 66045 (K.M.B., C.A.W., J.K.W.);Odum School of Ecology and Department of Genetics, University of Georgia, Athens, Georgia 30602 (J.T.A., S.M.W.); andGeography Department, Kansas State University, Manhattan, Kansas 66506 (L.M.G.)
| | - Joy K Ward
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, Kansas 66045 (K.M.B., C.A.W., J.K.W.);Odum School of Ecology and Department of Genetics, University of Georgia, Athens, Georgia 30602 (J.T.A., S.M.W.); andGeography Department, Kansas State University, Manhattan, Kansas 66506 (L.M.G.)
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Hager HA, Ryan GD, Kovacs HM, Newman JA. Effects of elevated CO2 on photosynthetic traits of native and invasive C3 and C4 grasses. BMC Ecol 2016; 16:28. [PMID: 27246099 PMCID: PMC4888642 DOI: 10.1186/s12898-016-0082-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Accepted: 05/19/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Rising CO2 is expected to result in changes in plant traits that will increase plant productivity for some functional groups. Differential plant responses to elevated CO2 are likely to drive changes in competitive outcomes, with consequences for community structure and plant diversity. Many of the traits that are enhanced under elevated CO2 also confer competitive success to invasive species, and it is widely believed that invasive species will be more successful in high CO2. However, this is likely to depend on plant functional group, and evidence suggests that C3 plants tend to respond more strongly to CO2. RESULTS We tested the hypothesis that invasive species would be more productive than noninvasive species under elevated CO2 and that stronger responses would be seen in C3 than C4 plants. We examined responses of 15 grass species (eight C3, seven C4), classified as noninvasive or invasive, to three levels of CO2 (390, 700 and 1000 ppm) in a closed chamber experiment. Elevated CO2 decreased conductance and %N and increased shoot biomass and C/N ratio across all species. Differences between invasive and noninvasive species depended on photosynthetic mechanism, with more differences for traits of C3 than C4 plants. Differences in trait means between invasive and noninvasive species tended to be similar across CO2 levels for many of the measured responses. However, noninvasive C3 grasses were more responsive than invasive C3 grasses in increasing tiller number and root biomass with elevated CO2, whereas noninvasive C4 grasses were more responsive than invasive C4 grasses in increasing shoot and root biomass with elevated CO2. For C3 grasses, these differences could be disadvantageous for noninvasive species under light competition, whereas for C4 grasses, noninvasive species may become better competitors with invasive species under increasing CO2. CONCLUSIONS The ecophysiological mechanisms underlying invasion success of C3 and C4 grasses may differ. However, given that the direction of trait differences between invasive and noninvasive grasses remained consistent under ambient and elevated CO2, our results provide evidence that increases in CO2 are unlikely to change dramatically the competitive hierarchy of grasses in these functional groups.
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Affiliation(s)
- Heather A. Hager
- />School of Environmental Sciences, University of Guelph, Guelph, ON N1G 2W1 Canada
- />Department of Integrative Biology, University of Guelph, Guelph, ON N1G 2W1 Canada
| | - Geraldine D. Ryan
- />School of Environmental Sciences, University of Guelph, Guelph, ON N1G 2W1 Canada
| | - Hajnal M. Kovacs
- />School of Environmental Sciences, University of Guelph, Guelph, ON N1G 2W1 Canada
| | - Jonathan A. Newman
- />School of Environmental Sciences, University of Guelph, Guelph, ON N1G 2W1 Canada
- />Department of Integrative Biology, University of Guelph, Guelph, ON N1G 2W1 Canada
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