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Kimura K, Kumagai E, Fushimi E, Maruyama A. Alternative method for determining leaf CO 2 assimilation without gas exchange measurements: Performance, comparison and sensitivity analysis. PLANT, CELL & ENVIRONMENT 2024; 47:992-1002. [PMID: 38098202 DOI: 10.1111/pce.14780] [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: 07/07/2023] [Revised: 11/20/2023] [Accepted: 11/27/2023] [Indexed: 12/20/2023]
Abstract
We present an alternative method to determine leaf CO2 assimilation rate (An ), eliminating the need for gas exchange measurements in proximal and remote sensing. This method combines the Farquhar-von Caemmerer-Berry photosynthesis model with mechanistic light reaction (MLR) theory and leaf energy balance (EB) analysis. The MLR theory estimates the actual electron transport rate (J) by leveraging chlorophyll fluorescence via pulse amplitude-modulated fluorometry for proximal sensing or sun-induced chlorophyll fluorescence measurements for remote sensing, along with spectral reflectance. The EB equation is used to directly estimate stomatal conductance from leaf temperature. In wheat and soybean, the MLR-EB model successfully estimated An variations, including midday depression, under various environmental and phenological conditions. Sensitivity analysis revealed that the leaf boundary layer conductance (gb ) played an equal, if not more, crucial role compared to the variables for J. This was primarily caused by the indirect influence of gb through the EB equation rather than its direct impact on convective CO2 exchange on the leaf. Although the MLR-EB model requires an accurate estimation of gb , it can potentially reduce uncertainties and enhance applicability in photosynthesis assessment when gas exchange measurements are unavailable.
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Affiliation(s)
- Kensuke Kimura
- Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization (NARO), Tsukuba, Japan
| | - Etsushi Kumagai
- Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization (NARO), Tsukuba, Japan
| | - Erina Fushimi
- Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization (NARO), Tsukuba, Japan
| | - Atsushi Maruyama
- Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization (NARO), Tsukuba, Japan
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2
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Baek W, Bae Y, Lim CW, Lee SC. Pepper homeobox abscisic acid signalling-related transcription factor 1, CaHAT1, plays a positive role in drought response. PLANT, CELL & ENVIRONMENT 2023. [PMID: 37128851 DOI: 10.1111/pce.14597] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 03/15/2023] [Accepted: 04/17/2023] [Indexed: 05/03/2023]
Abstract
Abscisic acid (ABA) signalling triggers drought resistance mediated by SNF1-related kinase 2s (SnRK2s), which transmits stress signals through the phosphorylation of several downstream factors. However, these kinases and their downstream targets remain elusive in pepper plants. This study aimed to isolate interacting partners of CaSnRK2.6, a homologue of Arabidopsis SnRK2.6/OST1. Among the candidate proteins, we identified a homeodomain-leucine zipper (HD-Zip) class II protein and named it CaHAT1 (Capsicum annuum homeobox ABA signalling related- transcription factor 1). CaHAT1-silenced pepper and -overexpression (OE) transgenic Arabidopsis plants were generated to investigate the in vivo function of CaHAT1 in drought response. Following the application of drought stress, CaHAT1-silenced pepper plants exhibited drought-sensitive phenotypes with reduced ABA-mediated stomatal closure and lower expression of stress-responsive genes compared with control plants. In contrast, CaHAT1-OE transgenic Arabidopsis plants showed the opposite phenotypes, including increased drought resistance and ABA sensitivity. CaHAT1, particularly its N-terminal consensus sequences, was directly phosphorylated by CaSnRK2.6. Furthermore, CaSnRK2.6 kinase activity and CaSnRK2.6-mediated CaHAT1 phosphorylation levels were enhanced by treatment with ABA and drought stress. Taken together, our results indicated that CaHAT1, which is the target protein of CaSnRK2.6, is a positive regulator of drought stress response. This study advances our understanding of CaHAT1-CaSnRK2.6 mediated defence mechanisms in pepper plants against drought stress.
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Affiliation(s)
- Woonhee Baek
- Department of Life Science (BK21 program), Chung-Ang University, Seoul, Korea
| | - Yeongil Bae
- Department of Life Science (BK21 program), Chung-Ang University, Seoul, Korea
| | - Chae Woo Lim
- Department of Life Science (BK21 program), Chung-Ang University, Seoul, Korea
| | - Sung Chul Lee
- Department of Life Science (BK21 program), Chung-Ang University, Seoul, Korea
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Wall S, Cockram J, Vialet-Chabrand S, Van Rie J, Gallé A, Lawson T. The impact of growth at elevated [CO2] on stomatal anatomy and behavior differs between wheat species and cultivars. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:2860-2874. [PMID: 36633860 PMCID: PMC10134898 DOI: 10.1093/jxb/erad011] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 01/11/2023] [Indexed: 06/06/2023]
Abstract
The ability of plants to respond to changes in the environment is crucial to their survival and reproductive success. The impact of increasing the atmospheric CO2 concentration (a[CO2]), mediated by behavioral and developmental responses of stomata, on crop performance remains a concern under all climate change scenarios, with potential impacts on future food security. To identify possible beneficial traits that could be exploited for future breeding, phenotypic variation in morphological traits including stomatal size and density, as well as physiological responses and, critically, the effect of growth [CO2] on these traits, was assessed in six wheat relative accessions (including Aegilops tauschii, Triticum turgidum ssp. Dicoccoides, and T. turgidum ssp. dicoccon) and five elite bread wheat T. aestivum cultivars. Exploiting a range of different species and ploidy, we identified key differences in photosynthetic capacity between elite hexaploid wheat and wheat relatives. We also report differences in the speed of stomatal responses which were found to be faster in wheat relatives than in elite cultivars, a trait that could be useful for enhanced photosynthetic carbon gain and water use efficiency. Furthermore, these traits do not all appear to be influenced by elevated [CO2], and determining the underlying genetics will be critical for future breeding programmes.
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Affiliation(s)
- Shellie Wall
- School of Life Sciences, University of Essex, Colchester CO4 3SQ, UK
| | - James Cockram
- NIAB, 93 Lawrence Weaver Road, Cambridge CB3 0LE, UK
| | | | - Jeroen Van Rie
- BASF Belgium Coordination Center CommV-Innovation Center Gent, Technologiepark-Zwijnaarde 101, 9052 Gent, Belgium
| | - Alexander Gallé
- BASF Belgium Coordination Center CommV-Innovation Center Gent, Technologiepark-Zwijnaarde 101, 9052 Gent, Belgium
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Chen Y, Zhu W, Yan T, Chen D, Jiang L, Chen ZH, Wu D. Stomatal morphological variation contributes to global ecological adaptation and diversification of Brassica napus. PLANTA 2022; 256:64. [PMID: 36029339 DOI: 10.1007/s00425-022-03982-4] [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: 06/29/2022] [Accepted: 08/22/2022] [Indexed: 06/15/2023]
Abstract
Stomatal density and guard cell length of 274 global core germplasms of rapeseed reveal that the stomatal morphological variation contributes to global ecological adaptation and diversification of Brassica napus. Stomata are microscopic structures of plants for the regulation of CO2 assimilation and transpiration. Stomatal morphology has changed substantially in the adaptation to the external environment during land plant evolution. Brassica napus is a major crop to produce oil, livestock feed and biofuel in the world. However, there are few studies on the regulatory genes controlling stomatal development and their interaction with environmental factors as well as the genetic mechanism of adaptive variation in B. napus. Here, we characterized stomatal density (SD) and guard cell length (GL) of 274 global core germplasms at seedling stage. It was found that among the significant phenotypic variation, European germplasms are mostly winter rapeseed with high stomatal density and small guard cell length. However, the germplasms from Asia (especially China) are semi-winter rapeseed, which is characterized by low stomatal density and large guard cell length. Through selective sweep analysis and homology comparison, we identified several candidate genes related to stomatal density and guard cell length, including Epidermal Patterning Factor2 (EPF2; BnaA09g23140D), Epidermal Patterning Factor Like4 (EPFL4; BnaC01g22890D) and Suppressor of LLP1 (SOL1 BnaC01g22810D). Haplotype and phylogenetic analysis showed that natural variation in EPF2, EPFL4 and SOL1 is closely associated with the winter, spring, and semi-winter rapeseed ecotypes. In summary, this study demonstrated for the first time the relation between stomatal phenotypic variation and ecological adaptation in rapeseed, which is useful for future molecular breeding of rapeseed in the context of evolution and domestication of key stomatal traits and global climate change.
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Affiliation(s)
- Yeke Chen
- Department of Agronomy, Key Laboratory of Crop Germplasm Resource of Zhejiang Province, Zhejiang University, Hangzhou, 310058, China
| | - Weizhuo Zhu
- Department of Agronomy, Key Laboratory of Crop Germplasm Resource of Zhejiang Province, Zhejiang University, Hangzhou, 310058, China
| | - Tao Yan
- College of Agronomy, Hunan Agricultural University, Changsha, 410128, China
| | - Danyi Chen
- Department of Agronomy, Key Laboratory of Crop Germplasm Resource of Zhejiang Province, Zhejiang University, Hangzhou, 310058, China
| | - Lixi Jiang
- Department of Agronomy, Key Laboratory of Crop Germplasm Resource of Zhejiang Province, Zhejiang University, Hangzhou, 310058, China
| | - Zhong-Hua Chen
- School of Science, Western Sydney University, Penrith, NSW, Australia.
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia.
| | - Dezhi Wu
- Department of Agronomy, Key Laboratory of Crop Germplasm Resource of Zhejiang Province, Zhejiang University, Hangzhou, 310058, China.
- College of Agronomy, Hunan Agricultural University, Changsha, 410128, China.
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5
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Pignon CP, Fernandes SB, Valluru R, Bandillo N, Lozano R, Buckler E, Gore MA, Long SP, Brown PJ, Leakey ADB. Phenotyping stomatal closure by thermal imaging for GWAS and TWAS of water use efficiency-related genes. PLANT PHYSIOLOGY 2021; 187:2544-2562. [PMID: 34618072 PMCID: PMC8644692 DOI: 10.1093/plphys/kiab395] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 07/26/2021] [Indexed: 05/07/2023]
Abstract
Stomata allow CO2 uptake by leaves for photosynthetic assimilation at the cost of water vapor loss to the atmosphere. The opening and closing of stomata in response to fluctuations in light intensity regulate CO2 and water fluxes and are essential for maintaining water-use efficiency (WUE). However, a little is known about the genetic basis for natural variation in stomatal movement, especially in C4 crops. This is partly because the stomatal response to a change in light intensity is difficult to measure at the scale required for association studies. Here, we used high-throughput thermal imaging to bypass the phenotyping bottleneck and assess 10 traits describing stomatal conductance (gs) before, during and after a stepwise decrease in light intensity for a diversity panel of 659 sorghum (Sorghum bicolor) accessions. Results from thermal imaging significantly correlated with photosynthetic gas exchange measurements. gs traits varied substantially across the population and were moderately heritable (h2 up to 0.72). An integrated genome-wide and transcriptome-wide association study identified candidate genes putatively driving variation in stomatal conductance traits. Of the 239 unique candidate genes identified with the greatest confidence, 77 were putative orthologs of Arabidopsis (Arabidopsis thaliana) genes related to functions implicated in WUE, including stomatal opening/closing (24 genes), stomatal/epidermal cell development (35 genes), leaf/vasculature development (12 genes), or chlorophyll metabolism/photosynthesis (8 genes). These findings demonstrate an approach to finding genotype-to-phenotype relationships for a challenging trait as well as candidate genes for further investigation of the genetic basis of WUE in a model C4 grass for bioenergy, food, and forage production.
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Affiliation(s)
- Charles P Pignon
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Samuel B Fernandes
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Ravi Valluru
- Institute for Genomic Diversity, Cornell University, Ithaca, New York 14853, USA
- Lincoln Institute for Agri-Food Technology, University of Lincoln, Lincoln LN1 3QE, UK
| | - Nonoy Bandillo
- Institute for Genomic Diversity, Cornell University, Ithaca, New York 14853, USA
- Department of Plant Sciences, North Dakota State University, Fargo, North Dakota 58105, USA
| | - Roberto Lozano
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, New York 14853, USA
| | - Edward Buckler
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, New York 14853, USA
- United States Department of Agriculture, Agricultural Research Service (USDA-ARS) R.W. Holley Center for Agriculture and Health, Ithaca, New York 14853, USA
| | - Michael A Gore
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, New York 14853, USA
| | - Stephen P Long
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Lancaster Environment Centre, University of Lancaster, Lancaster LA1 1YX, UK
| | - Patrick J Brown
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Andrew D B Leakey
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Institute for Genomic Diversity, Cornell University, Ithaca, New York 14853, USA
- Author for communication:
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Hunt L, Fuksa M, Klem K, Lhotáková Z, Oravec M, Urban O, Albrechtová J. Barley Genotypes Vary in Stomatal Responsiveness to Light and CO 2 Conditions. PLANTS (BASEL, SWITZERLAND) 2021; 10:plants10112533. [PMID: 34834896 PMCID: PMC8625854 DOI: 10.3390/plants10112533] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/16/2021] [Accepted: 11/18/2021] [Indexed: 05/03/2023]
Abstract
Changes in stomatal conductance and density allow plants to acclimate to changing environmental conditions. In the present paper, the influence of atmospheric CO2 concentration and light intensity on stomata were investigated for two barley genotypes-Barke and Bojos, differing in their sensitivity to oxidative stress and phenolic acid profiles. A novel approach for stomatal density analysis was used-a pair of convolution neural networks were developed to automatically identify and count stomata on epidermal micrographs. Stomatal density in barley was influenced by genotype, as well as by light and CO2 conditions. Low CO2 conditions resulted in increased stomatal density, although differences between ambient and elevated CO2 were not significant. High light intensity increased stomatal density compared to low light intensity in both barley varieties and all CO2 treatments. Changes in stomatal conductance were also measured alongside the accumulation of pentoses, hexoses, disaccharides, and abscisic acid detected by liquid chromatography coupled with mass spectrometry. High light increased the accumulation of all sugars and reduced abscisic acid levels. Abscisic acid was influenced by all factors-light, CO2, and genotype-in combination. Differences were discovered between the two barley varieties: oxidative stress sensitive Barke demonstrated higher stomatal density, but lower conductance and better water use efficiency (WUE) than oxidative stress resistant Bojos at saturating light intensity. Barke also showed greater variability between treatments in measurements of stomatal density, sugar accumulation, and abscisic levels, implying that it may be more responsive to environmental drivers influencing water relations in the plant.
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Affiliation(s)
- Lena Hunt
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 12844 Praha, Czech Republic; (L.H.); (M.F.); (Z.L.)
| | - Michal Fuksa
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 12844 Praha, Czech Republic; (L.H.); (M.F.); (Z.L.)
| | - Karel Klem
- Global Change Research Institute, Czech Academy of Sciences, Bělidla 4a, 60300 Brno, Czech Republic; (K.K.); (M.O.); (O.U.)
| | - Zuzana Lhotáková
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 12844 Praha, Czech Republic; (L.H.); (M.F.); (Z.L.)
| | - Michal Oravec
- Global Change Research Institute, Czech Academy of Sciences, Bělidla 4a, 60300 Brno, Czech Republic; (K.K.); (M.O.); (O.U.)
| | - Otmar Urban
- Global Change Research Institute, Czech Academy of Sciences, Bělidla 4a, 60300 Brno, Czech Republic; (K.K.); (M.O.); (O.U.)
| | - Jana Albrechtová
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 12844 Praha, Czech Republic; (L.H.); (M.F.); (Z.L.)
- Correspondence: ; Tel.: +420-221-95-1959
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Taxonomic Revisiting and Phylogenetic Placement of Two Endangered Plant Species: Silene leucophylla Boiss. and Silene schimperiana Boiss. (Caryophyllaceae). PLANTS 2021; 10:plants10040740. [PMID: 33918962 PMCID: PMC8070032 DOI: 10.3390/plants10040740] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Revised: 04/06/2021] [Accepted: 04/06/2021] [Indexed: 11/17/2022]
Abstract
The genus Silene L. is one of the largest genera in Caryophyllaceae, and is distributed in the Northern Hemisphere and South America. The endemic species Silene leucophylla and the near-endemic S. schimperiana are native to the Sinai Peninsula, Egypt. They have reduced population size and are endangered on national and international scales. These two species have typically been disregarded in most studies of the genus Silene. This research integrates the Scanning Electron Microscope (SEM), species micromorphology, and the phylogenetic analysis of four DNA markers: ITS, matK, rbcL and psb-A/trn-H. Trichomes were observed on the stem of Silene leucophylla, while the S. schimperiana has a glabrous stem. Irregular epicuticle platelets with sinuate margin were found in S. schimperiana. Oblong, bone-shaped, and irregularly arranged epidermal cells were present on the leaf of S. leucophylla, while Silene schimperiana leaf has "tetra-, penta-, hexa-, and polygonal" epidermal cells. Silene leucophylla and S. schimperiana have amphistomatic stomata. The Bayesian phylogenetic analysis of each marker individually or in combination represented the first phylogenetic study to reveal the generic and sectional classification of S. leucophylla and S. schimperiana. Two Silene complexes are proposed based on morphological and phylogenetic data. The Leucophylla complex was allied to section Siphonomorpha and the Schimperiana complex was related to section Sclerocalycinae. However, these two complexes need further investigation and more exhaustive sampling to infer their complex phylogenetic relationships.
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Rosero A, Granda L, Berdugo-Cely JA, Šamajová O, Šamaj J, Cerkal R. A Dual Strategy of Breeding for Drought Tolerance and Introducing Drought-Tolerant, Underutilized Crops into Production Systems to Enhance Their Resilience to Water Deficiency. PLANTS (BASEL, SWITZERLAND) 2020; 9:E1263. [PMID: 32987964 PMCID: PMC7600178 DOI: 10.3390/plants9101263] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/19/2020] [Accepted: 09/22/2020] [Indexed: 02/06/2023]
Abstract
Water scarcity is the primary constraint on crop productivity in arid and semiarid tropical areas suffering from climate alterations; in accordance, agricultural systems have to be optimized. Several concepts and strategies should be considered to improve crop yield and quality, particularly in vulnerable regions where such environmental changes cause a risk of food insecurity. In this work, we review two strategies aiming to increase drought stress tolerance: (i) the use of natural genes that have evolved over time and are preserved in crop wild relatives and landraces for drought tolerance breeding using conventional and molecular methods and (ii) exploiting the reservoir of neglected and underutilized species to identify those that are known to be more drought-tolerant than conventional staple crops while possessing other desired agronomic and nutritive characteristics, as well as introducing them into existing cropping systems to make them more resilient to water deficiency conditions. In the past, the existence of drought tolerance genes in crop wild relatives and landraces was either unknown or difficult to exploit using traditional breeding techniques to secure potential long-term solutions. Today, with the advances in genomics and phenomics, there are a number of new tools available that facilitate the discovery of drought resistance genes in crop wild relatives and landraces and their relatively easy transfer into advanced breeding lines, thus accelerating breeding progress and creating resilient varieties that can withstand prolonged drought periods. Among those tools are marker-assisted selection (MAS), genomic selection (GS), and targeted gene editing (clustered regularly interspaced short palindromic repeat (CRISPR) technology). The integration of these two major strategies, the advances in conventional and molecular breeding for the drought tolerance of conventional staple crops, and the introduction of drought-tolerant neglected and underutilized species into existing production systems has the potential to enhance the resilience of agricultural production under conditions of water scarcity.
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Affiliation(s)
- Amparo Rosero
- Corporación Colombiana de Investigación Agropecuaria–AGROSAVIA, Centro de Investigación Turipaná, Km 13 vía Montería, 250047 Cereté, Colombia;
| | - Leiter Granda
- Department of Crop Science, Breeding and Plant Medicine, Mendel University in Brno, Zemedelska 1, 613 00 Brno, Czech Republic; (L.G.); (R.C.)
| | - Jhon A. Berdugo-Cely
- Corporación Colombiana de Investigación Agropecuaria–AGROSAVIA, Centro de Investigación Turipaná, Km 13 vía Montería, 250047 Cereté, Colombia;
| | - Olga Šamajová
- Department of Cell Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic; (O.Š.); (J.Š.)
| | - Jozef Šamaj
- Department of Cell Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic; (O.Š.); (J.Š.)
| | - Radim Cerkal
- Department of Crop Science, Breeding and Plant Medicine, Mendel University in Brno, Zemedelska 1, 613 00 Brno, Czech Republic; (L.G.); (R.C.)
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9
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Johansson KSL, El-Soda M, Pagel E, Meyer RC, Tõldsepp K, Nilsson AK, Brosché M, Kollist H, Uddling J, Andersson MX. Genetic controls of short- and long-term stomatal CO2 responses in Arabidopsis thaliana. ANNALS OF BOTANY 2020; 126:179-190. [PMID: 32296835 PMCID: PMC7304471 DOI: 10.1093/aob/mcaa065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 04/09/2020] [Indexed: 05/14/2023]
Abstract
BACKGROUND AND AIMS The stomatal conductance (gs) of most plant species decreases in response to elevated atmospheric CO2 concentration. This response could have a significant impact on plant water use in a future climate. However, the regulation of the CO2-induced stomatal closure response is not fully understood. Moreover, the potential genetic links between short-term (within minutes to hours) and long-term (within weeks to months) responses of gs to increased atmospheric CO2 have not been explored. METHODS We used Arabidopsis thaliana recombinant inbred lines originating from accessions Col-0 (strong CO2 response) and C24 (weak CO2 response) to study short- and long-term controls of gs. Quantitative trait locus (QTL) mapping was used to identify loci controlling short- and long-term gs responses to elevated CO2, as well as other stomata-related traits. KEY RESULTS Short- and long-term stomatal responses to elevated CO2 were significantly correlated. Both short- and long-term responses were associated with a QTL at the end of chromosome 2. The location of this QTL was confirmed using near-isogenic lines and it was fine-mapped to a 410-kb region. The QTL did not correspond to any known gene involved in stomatal closure and had no effect on the responsiveness to abscisic acid. Additionally, we identified numerous other loci associated with stomatal regulation. CONCLUSIONS We identified and confirmed the effect of a strong QTL corresponding to a yet unknown regulator of stomatal closure in response to elevated CO2 concentration. The correlation between short- and long-term stomatal CO2 responses and the genetic link between these traits highlight the importance of understanding guard cell CO2 signalling to predict and manipulate plant water use in a world with increasing atmospheric CO2 concentration. This study demonstrates the power of using natural variation to unravel the genetic regulation of complex traits.
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Affiliation(s)
- Karin S L Johansson
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
- Institute of Technology, University of Tartu, Tartu, Estonia
| | - Mohamed El-Soda
- Department of Genetics, Faculty of Agriculture, Cairo University, Cairo, Egypt
| | - Ellen Pagel
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Rhonda C Meyer
- Department of Molecular Genetics, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Seeland, Germany
| | - Kadri Tõldsepp
- Institute of Technology, University of Tartu, Tartu, Estonia
| | - Anders K Nilsson
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Mikael Brosché
- Institute of Technology, University of Tartu, Tartu, Estonia
- Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Hannes Kollist
- Institute of Technology, University of Tartu, Tartu, Estonia
| | - Johan Uddling
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Mats X Andersson
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
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10
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Steady-State Levels of Cytokinins and Their Derivatives May Serve as a Unique Classifier of Arabidopsis Ecotypes. PLANTS 2020; 9:plants9010116. [PMID: 31963497 PMCID: PMC7020191 DOI: 10.3390/plants9010116] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 01/14/2020] [Accepted: 01/15/2020] [Indexed: 11/17/2022]
Abstract
We determined steady-state (basal) endogenous levels of three plant hormones (abscisic acid, cytokinins and indole-3-acetic acid) in a collection of thirty different ecotypes of Arabidopsis that represent a broad genetic variability within this species. Hormone contents were analysed separately in plant shoots and roots after 21 days of cultivation on agar plates in a climate-controlled chamber. Using advanced statistical and machine learning methods, we tested if basal hormonal levels can be considered a unique ecotype-specific classifier. We also explored possible relationships between hormone levels and the prevalent environmental conditions in the site of origin for each ecotype. We found significant variations in basal hormonal levels and their ratios in both root and shoot among the ecotypes. We showed the prominent position of cytokinins (CK) among the other hormones. We found the content of CK and CK metabolites to be a reliable ecotype-specific identifier. Correlation with the mean temperature at the site of origin and the large variation in basal hormonal levels suggest that the high variability may potentially be in response to environmental factors. This study provides a starting point for ecotype-specific genetic maps of the CK metabolic and signalling network to explore its contribution to the adaptation of plants to local environmental conditions.
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11
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Kübarsepp L, Laanisto L, Niinemets Ü, Talts E, Tosens T. Are stomata in ferns and allies sluggish? Stomatal responses to CO 2 , humidity and light and their scaling with size and density. THE NEW PHYTOLOGIST 2020; 225:183-195. [PMID: 31479517 DOI: 10.1111/nph.16159] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Accepted: 08/15/2019] [Indexed: 06/10/2023]
Abstract
Fast stomatal reactions enable plants to successfully cope with a constantly changing environment yet there is an ongoing debate on the stomatal regulation mechanisms in basal plant groups. We measured stomatal morphological parameters in 29 fern and allied species from temperate to tropical biomes and two outgroup angiosperm species. Stomatal dynamic responses to environmental drivers were measured in 16 ferns and the two angiosperms using a gas-exchange system. Principal components analyses were used to further reveal the structure-function relationships in stomata. We show a > 10-fold variation for stomatal opening delays and 20-fold variation for stomatal closing delays in ferns. Across species, stomatal responses to vapor pressure deficit (VPD) were the fastest, while light and [CO2 ] responses were slower. In most cases the outgroup species' reaction speeds to changes in environmental variables were similar to those of ferns. Correlations between stomatal response rate and size were apparent for stomatal opening in light and low [CO2 ] while not evident for closing reactions and changes in VPD. No correlations between stomatal density and response speed were observed. Together, this study demonstrates different mechanisms controlling stomatal reactions in ferns at different environmental stimuli, which should be considered in future studies relating stomatal morphology and function.
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Affiliation(s)
- Liisa Kübarsepp
- Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 1, Tartu, 51014, Estonia
| | - Lauri Laanisto
- Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 1, Tartu, 51014, Estonia
| | - Ülo Niinemets
- Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 1, Tartu, 51014, Estonia
- Estonian Academy of Sciences, Kohtu 6, Tallinn, 10130, Estonia
| | - Eero Talts
- Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 1, Tartu, 51014, Estonia
| | - Tiina Tosens
- Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 1, Tartu, 51014, Estonia
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12
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Cernusak LA, Goldsmith GR, Arend M, Siegwolf RTW. Effect of Vapor Pressure Deficit on Gas Exchange in Wild-Type and Abscisic Acid-Insensitive Plants. PLANT PHYSIOLOGY 2019; 181:1573-1586. [PMID: 31562233 PMCID: PMC6878010 DOI: 10.1104/pp.19.00436] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 09/08/2019] [Indexed: 05/25/2023]
Abstract
Stomata control the gas exchange of terrestrial plant leaves, and are therefore essential to plant growth and survival. We investigated gas exchange responses to vapor pressure deficit (VPD) in two gray poplar (Populus × canescens) lines: wild type and abscisic acid-insensitive (abi1) with functionally impaired stomata. Transpiration rate in abi1 increased linearly with VPD, up to about 2 kPa. Above this, sharply declining transpiration was followed by leaf death. In contrast, wild type showed a steady or slightly declining transpiration rate up to VPD of nearly 7 kPa, and fully recovered photosynthetic function afterward. There were marked differences in discrimination against 13CO2 (Δ13C) and C18OO (Δ18O) between abi1 and wild-type plants. The Δ13C indicated that intercellular CO2 concentrations decreased with VPD in wild-type plants, but not in abi1 plants. The Δ18O reflected progressive stomatal closure in wild type in response to increasing VPD; however, in abi1, stomata remained open and oxygen atoms of CO2 continued to exchange with 18O enriched leaf water. Coupled measurements of Δ18O and gas exchange were used to estimate intercellular vapor pressure, e i In wild-type leaves, there was no evidence of unsaturation of e i, even at VPD above 6 kPa. In abi1 leaves, e i approached 0.6 times saturation vapor pressure before the precipitous decline in transpiration rate. For wild type, a sensitive stomatal response to increasing VPD was pivotal in preventing unsaturation of e i In abi1, after taking unsaturation into account, stomatal conductance increased with increasing VPD, consistent with a disabled active response of guard cell osmotic pressure.
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Affiliation(s)
- Lucas A Cernusak
- College of Science and Engineering, James Cook University, Cairns, Queensland 4879, Australia
| | - Gregory R Goldsmith
- Ecosystem Fluxes and Stable Isotope Research Group, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - Matthias Arend
- Physiological Plant Ecology Group, University of Basel, 4001 Basel, Switzerland
| | - Rolf T W Siegwolf
- Ecosystem Fluxes and Stable Isotope Research Group, Paul Scherrer Institute, 5232 Villigen, Switzerland
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13
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Fetter KC, Eberhardt S, Barclay RS, Wing S, Keller SR. StomataCounter: a neural network for automatic stomata identification and counting. THE NEW PHYTOLOGIST 2019; 223:1671-1681. [PMID: 31059134 DOI: 10.1111/nph.15892] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 04/21/2019] [Indexed: 05/18/2023]
Abstract
Stomata regulate important physiological processes in plants and are often phenotyped by researchers in diverse fields of plant biology. Currently, there are no user-friendly, fully automated methods to perform the task of identifying and counting stomata, and stomata density is generally estimated by manually counting stomata. We introduce StomataCounter, an automated stomata counting system using a deep convolutional neural network to identify stomata in a variety of different microscopic images. We use a human-in-the-loop approach to train and refine a neural network on a taxonomically diverse collection of microscopic images. Our network achieves 98.1% identification accuracy on Ginkgo scanning electron microscropy micrographs, and 94.2% transfer accuracy when tested on untrained species. To facilitate adoption of the method, we provide the method in a publicly available website at http://www.stomata.science/.
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Affiliation(s)
- Karl C Fetter
- Department of Plant Biology, University of Vermont, Burlington, VT, 05405, USA
- Department of Paleobiology, Smithsonian Institution, National Museum of Natural History, Washington, DC, 20560, USA
| | | | - Rich S Barclay
- Department of Paleobiology, Smithsonian Institution, National Museum of Natural History, Washington, DC, 20560, USA
| | - Scott Wing
- Department of Paleobiology, Smithsonian Institution, National Museum of Natural History, Washington, DC, 20560, USA
| | - Stephen R Keller
- Department of Plant Biology, University of Vermont, Burlington, VT, 05405, USA
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14
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Faralli M, Matthews J, Lawson T. Exploiting natural variation and genetic manipulation of stomatal conductance for crop improvement. CURRENT OPINION IN PLANT BIOLOGY 2019; 49:1-7. [PMID: 30851622 PMCID: PMC6692497 DOI: 10.1016/j.pbi.2019.01.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 12/21/2018] [Accepted: 01/28/2019] [Indexed: 05/19/2023]
Abstract
Rising global temperatures and more frequent episodes of drought are expected to drive reductions in crop yield, therefore new avenues for improving crop productivity must be exploited. Stomatal conductance (gs) balances plant CO2 uptake and water loss, therefore, greatly impacting the cumulative rate of photosynthesis and water use over the growing season, which are key determinants of crop yield and productivity. Considerable natural variation exists in stomatal anatomy, biochemistry and behavioural characteristics that impact on the kinetics and magnitude of gs and thus gaseous exchange between the plant and atmosphere. Exploiting these differences in stomatal traits could provide novel breeding targets for new crop varieties that are potentially more water use efficient and have the ability to maintain and/or maximize yield in a range of diverse environments. Here we provide an overview of variation in stomatal traits and the impact these have on gs behaviour, as well as the potential to exploit such variation and genetic manipulation for crop improvement.
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Affiliation(s)
- Michele Faralli
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, United Kingdom
| | - Jack Matthews
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, United Kingdom
| | - Tracy Lawson
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, United Kingdom.
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15
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Vialet-Chabrand S, Lawson T. Dynamic leaf energy balance: deriving stomatal conductance from thermal imaging in a dynamic environment. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:2839-2855. [PMID: 30793211 PMCID: PMC6506762 DOI: 10.1093/jxb/erz068] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 02/11/2019] [Indexed: 05/20/2023]
Abstract
In spite of the significant progress made in recent years, the use of thermography to derive biologically relevant traits remains a challenge under fluctuating conditions. The aim of this study was to rethink the current method to process thermograms and derive temporal responses of stomatal conductance (gsw) using dynamic energy balance equations. Time-series thermograms provided the basis for a spatial and temporal characterization of gsw responses in wheat (Triticum aestivum). A leaf replica with a known conductance was used to validate the approach and to test the ability of our model to be used with any material and under any environmental conditions. The results highlighted the importance of the co-ordinated stomatal responses that run parallel to the leaf blade despite their patchy distribution. The diversity and asymmetry of the temporal response of gsw observed after a step increase and step decrease in light intensity can be interpreted as a strategy to maximize photosynthesis per unit of water loss and avoid heat stress in response to light flecks in a natural environment. This study removes a major bottleneck for plant phenotyping platforms and will pave the way to further developments in our understanding of stomatal behaviour.
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Affiliation(s)
| | - Tracy Lawson
- School of Biological Sciences, University of Essex, Colchester, UK
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16
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Tomeo NJ, Rosenthal DM. Photorespiration differs among Arabidopsis thaliana ecotypes and is correlated with photosynthesis. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:5191-5204. [PMID: 30053111 PMCID: PMC6184796 DOI: 10.1093/jxb/ery274] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 07/16/2018] [Indexed: 05/19/2023]
Abstract
A greater understanding of natural variation in photosynthesis will inform strategies for crop improvement by revealing overlooked opportunities. We use Arabidopsis thaliana ecotypes as a model system to assess (i) how photosynthesis and photorespiration covary and (ii) how mesophyll conductance influences water use efficiency (WUE). Phenotypic variation in photorespiratory CO2 efflux was correlated with assimilation rates and two metrics of photosynthetic capacity (i.e. VCmax and Jmax); however, genetic correlations were not detected between photosynthesis and photorespiration. We found standing genetic variation-as broad-sense heritability-for most photosynthetic traits, including photorespiration. Genetic correlation between photosynthetic electron transport and carboxylation capacities indicates that these traits are genetically constrained. Winter ecotypes had greater mesophyll conductance, maximum carboxylation capacity, maximum electron transport capacity, and leaf structural robustness when compared with spring ecotypes. Stomatal conductance varied little in winter ecotypes, leading to a positive correlation between integrated WUE and mesophyll conductance. Thus, variation in mesophyll conductance can modulate WUE among A. thaliana ecotypes without a significant loss in assimilation. Genetic correlations between traits supplying energy and carbon to the Calvin-Benson cycle are consistent with biochemical models, suggesting that selection on either of these traits would improve all of them. Similarly, the lack of a genetic correlation between photosynthesis and photorespiration suggests that the positive scaling of these two traits can be broken.
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Affiliation(s)
- Nicholas J Tomeo
- Ohio University, Department of Environmental and Plant Biology, Athens, OH, USA
| | - David M Rosenthal
- Ohio University, Department of Environmental and Plant Biology, Athens, OH, USA
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17
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Eisenach C, Baetz U, Huck NV, Zhang J, De Angeli A, Beckers GJM, Martinoia E. ABA-Induced Stomatal Closure Involves ALMT4, a Phosphorylation-Dependent Vacuolar Anion Channel of Arabidopsis. THE PLANT CELL 2017; 29:2552-2569. [PMID: 28874508 DOI: 10.1105/tpc.1117.00452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 08/09/2017] [Accepted: 08/31/2017] [Indexed: 05/24/2023]
Abstract
Stomatal pores are formed between a pair of guard cells and allow plant uptake of CO2 and water evaporation. Their aperture depends on changes in osmolyte concentration of guard cell vacuoles, specifically of K+ and Mal2- Efflux of Mal2- from the vacuole is required for stomatal closure; however, it is not clear how the anion is released. Here, we report the identification of ALMT4 (ALUMINUM ACTIVATED MALATE TRANSPORTER4) as an Arabidopsis thaliana ion channel that can mediate Mal2- release from the vacuole and is required for stomatal closure in response to abscisic acid (ABA). Knockout mutants showed impaired stomatal closure in response to the drought stress hormone ABA and increased whole-plant wilting in response to drought and ABA. Electrophysiological data show that ALMT4 can mediate Mal2- efflux and that the channel activity is dependent on a phosphorylatable C-terminal serine. Dephosphomimetic mutants of ALMT4 S382 showed increased channel activity and Mal2- efflux. Reconstituting the active channel in almt4 mutants impaired growth and stomatal opening. Phosphomimetic mutants were electrically inactive and phenocopied the almt4 mutants. Surprisingly, S382 can be phosphorylated by mitogen-activated protein kinases in vitro. In brief, ALMT4 likely mediates Mal2- efflux during ABA-induced stomatal closure and its activity depends on phosphorylation.
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Affiliation(s)
- Cornelia Eisenach
- Department of Plant and Microbial Biology, University of Zurich, CH-8008 Zurich, Switzerland
| | - Ulrike Baetz
- Department of Plant and Microbial Biology, University of Zurich, CH-8008 Zurich, Switzerland
| | - Nicola V Huck
- Department of Plant Physiology, Aachen Biology and Biotechnology, RWTH Aachen University, Aachen 52056, Germany
| | - Jingbo Zhang
- Department of Plant and Microbial Biology, University of Zurich, CH-8008 Zurich, Switzerland
| | - Alexis De Angeli
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette cedex, France
| | - Gerold J M Beckers
- Department of Plant Physiology, Aachen Biology and Biotechnology, RWTH Aachen University, Aachen 52056, Germany
| | - Enrico Martinoia
- Department of Plant and Microbial Biology, University of Zurich, CH-8008 Zurich, Switzerland
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18
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Eisenach C, Baetz U, Huck NV, Zhang J, De Angeli A, Beckers GJM, Martinoia E. ABA-Induced Stomatal Closure Involves ALMT4, a Phosphorylation-Dependent Vacuolar Anion Channel of Arabidopsis. THE PLANT CELL 2017; 29:2552-2569. [PMID: 28874508 PMCID: PMC5774580 DOI: 10.1105/tpc.17.00452] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 08/09/2017] [Accepted: 08/31/2017] [Indexed: 05/18/2023]
Abstract
Stomatal pores are formed between a pair of guard cells and allow plant uptake of CO2 and water evaporation. Their aperture depends on changes in osmolyte concentration of guard cell vacuoles, specifically of K+ and Mal2- Efflux of Mal2- from the vacuole is required for stomatal closure; however, it is not clear how the anion is released. Here, we report the identification of ALMT4 (ALUMINUM ACTIVATED MALATE TRANSPORTER4) as an Arabidopsis thaliana ion channel that can mediate Mal2- release from the vacuole and is required for stomatal closure in response to abscisic acid (ABA). Knockout mutants showed impaired stomatal closure in response to the drought stress hormone ABA and increased whole-plant wilting in response to drought and ABA. Electrophysiological data show that ALMT4 can mediate Mal2- efflux and that the channel activity is dependent on a phosphorylatable C-terminal serine. Dephosphomimetic mutants of ALMT4 S382 showed increased channel activity and Mal2- efflux. Reconstituting the active channel in almt4 mutants impaired growth and stomatal opening. Phosphomimetic mutants were electrically inactive and phenocopied the almt4 mutants. Surprisingly, S382 can be phosphorylated by mitogen-activated protein kinases in vitro. In brief, ALMT4 likely mediates Mal2- efflux during ABA-induced stomatal closure and its activity depends on phosphorylation.
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Affiliation(s)
- Cornelia Eisenach
- Department of Plant and Microbial Biology, University of Zurich, CH-8008 Zurich, Switzerland
| | - Ulrike Baetz
- Department of Plant and Microbial Biology, University of Zurich, CH-8008 Zurich, Switzerland
| | - Nicola V Huck
- Department of Plant Physiology, Aachen Biology and Biotechnology, RWTH Aachen University, Aachen 52056, Germany
| | - Jingbo Zhang
- Department of Plant and Microbial Biology, University of Zurich, CH-8008 Zurich, Switzerland
| | - Alexis De Angeli
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette cedex, France
| | - Gerold J M Beckers
- Department of Plant Physiology, Aachen Biology and Biotechnology, RWTH Aachen University, Aachen 52056, Germany
| | - Enrico Martinoia
- Department of Plant and Microbial Biology, University of Zurich, CH-8008 Zurich, Switzerland
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19
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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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20
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Eisenach C, De Angeli A. Ion Transport at the Vacuole during Stomatal Movements. PLANT PHYSIOLOGY 2017; 174:520-530. [PMID: 28381500 PMCID: PMC5462060 DOI: 10.1104/pp.17.00130] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 04/03/2017] [Indexed: 05/19/2023]
Abstract
Recent research on vacuolar ion channels, transporters, and pumps of Arabidopsis highlight their function and roles in stomatal opening and closure.
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Affiliation(s)
- Cornelia Eisenach
- Department of Plant and Microbial Biology, University of Zurich, Zurich CH-8008, Switzerland (C.E.); and
- Institut de Biologie Intégrative de la Cellule, Centre National de la Recherche Scientifique, 91190 Gif-sur-Yvette, France (A.D.A.)
| | - Alexis De Angeli
- Department of Plant and Microbial Biology, University of Zurich, Zurich CH-8008, Switzerland (C.E.); and
- Institut de Biologie Intégrative de la Cellule, Centre National de la Recherche Scientifique, 91190 Gif-sur-Yvette, France (A.D.A.)
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21
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Azoulay-Shemer T, Bagheri A, Wang C, Palomares A, Stephan AB, Kunz HH, Schroeder JI. Starch Biosynthesis in Guard Cells But Not in Mesophyll Cells Is Involved in CO2-Induced Stomatal Closing. PLANT PHYSIOLOGY 2016; 171:788-98. [PMID: 27208296 PMCID: PMC4902578 DOI: 10.1104/pp.15.01662] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 04/19/2016] [Indexed: 05/29/2023]
Abstract
Starch metabolism is involved in stomatal movement regulation. However, it remains unknown whether starch-deficient mutants affect CO2-induced stomatal closing and whether starch biosynthesis in guard cells and/or mesophyll cells is rate limiting for high CO2-induced stomatal closing. Stomatal responses to [CO2] shifts and CO2 assimilation rates were compared in Arabidopsis (Arabidopsis thaliana) mutants that were either starch deficient in all plant tissues (ADP-Glc-pyrophosphorylase [ADGase]) or retain starch accumulation in guard cells but are starch deficient in mesophyll cells (plastidial phosphoglucose isomerase [pPGI]). ADGase mutants exhibited impaired CO2-induced stomatal closure, but pPGI mutants did not, showing that starch biosynthesis in guard cells but not mesophyll functions in CO2-induced stomatal closing. Nevertheless, starch-deficient ADGase mutant alleles exhibited partial CO2 responses, pointing toward a starch biosynthesis-independent component of the response that is likely mediated by anion channels. Furthermore, whole-leaf CO2 assimilation rates of both ADGase and pPGI mutants were lower upon shifts to high [CO2], but only ADGase mutants caused impairments in CO2-induced stomatal closing. These genetic analyses determine the roles of starch biosynthesis for high CO2-induced stomatal closing.
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Affiliation(s)
- Tamar Azoulay-Shemer
- Division of Biological Sciences, Section of Cell and Developmental Biology, Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116
| | - Andisheh Bagheri
- Division of Biological Sciences, Section of Cell and Developmental Biology, Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116
| | - Cun Wang
- Division of Biological Sciences, Section of Cell and Developmental Biology, Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116
| | - Axxell Palomares
- Division of Biological Sciences, Section of Cell and Developmental Biology, Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116
| | - Aaron B Stephan
- Division of Biological Sciences, Section of Cell and Developmental Biology, Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116
| | - Hans-Henning Kunz
- Division of Biological Sciences, Section of Cell and Developmental Biology, Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116
| | - Julian I Schroeder
- Division of Biological Sciences, Section of Cell and Developmental Biology, Center for Food and Fuel for the 21st Century, University of California, San Diego, La Jolla, California 92093-0116
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22
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Nunes-Nesi A, Nascimento VDL, de Oliveira Silva FM, Zsögön A, Araújo WL, Sulpice R. Natural genetic variation for morphological and molecular determinants of plant growth and yield. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:2989-3001. [PMID: 27012286 DOI: 10.1093/jxb/erw124] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The rates of increase in yield of the main commercial crops have been steadily falling in many areas worldwide. This generates concerns because there is a growing demand for plant biomass due to the increasing population. Plant yield should thus be improved in the context of climate change and decreasing natural resources. It is a major challenge which could be tackled by improving and/or altering light-use efficiency, CO2 uptake and fixation, primary metabolism, plant architecture and leaf morphology, and developmental plant processes. In this review, we discuss some of the traits which could lead to yield increase, with a focus on how natural genetic variation could be harnessed. Moreover, we provide insights for advancing our understanding of the molecular aspects governing plant growth and yield, and propose future avenues for improvement of crop yield. We also suggest that knowledge accumulated over the last decade in the field of molecular physiology should be integrated into new ideotypes.
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Affiliation(s)
- Adriano Nunes-Nesi
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil Max-Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - Vitor de Laia Nascimento
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil Max-Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - Franklin Magnum de Oliveira Silva
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil Max-Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - Agustin Zsögön
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - Wagner L Araújo
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil Max-Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - Ronan Sulpice
- National University of Ireland, Galway, Plant Systems Biology Lab, Plant and AgriBiosciences Research Centre, School of Natural Sciences, Galway, Ireland
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23
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Monda K, Araki H, Kuhara S, Ishigaki G, Akashi R, Negi J, Kojima M, Sakakibara H, Takahashi S, Hashimoto-Sugimoto M, Goto N, Iba K. Enhanced Stomatal Conductance by a Spontaneous Arabidopsis Tetraploid, Me-0, Results from Increased Stomatal Size and Greater Stomatal Aperture. PLANT PHYSIOLOGY 2016; 170:1435-44. [PMID: 26754665 PMCID: PMC4775119 DOI: 10.1104/pp.15.01450] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 01/08/2016] [Indexed: 05/03/2023]
Abstract
The rate of gas exchange in plants is regulated mainly by stomatal size and density. Generally, higher densities of smaller stomata are advantageous for gas exchange; however, it is unclear what the effect of an extraordinary change in stomatal size might have on a plant's gas-exchange capacity. We investigated the stomatal responses to CO2 concentration changes among 374 Arabidopsis (Arabidopsis thaliana) ecotypes and discovered that Mechtshausen (Me-0), a natural tetraploid ecotype, has significantly larger stomata and can achieve a high stomatal conductance. We surmised that the cause of the increased stomatal conductance is tetraploidization; however, the stomatal conductance of another tetraploid accession, tetraploid Columbia (Col), was not as high as that in Me-0. One difference between these two accessions was the size of their stomatal apertures. Analyses of abscisic acid sensitivity, ion balance, and gene expression profiles suggested that physiological or genetic factors restrict the stomatal opening in tetraploid Col but not in Me-0. Our results show that Me-0 overcomes the handicap of stomatal opening that is typical for tetraploids and achieves higher stomatal conductance compared with the closely related tetraploid Col on account of larger stomatal apertures. This study provides evidence for whether larger stomatal size in tetraploids of higher plants can improve stomatal conductance.
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Affiliation(s)
- Keina Monda
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan (K.M., J.N., S.T., M.H.-S., K.I.);Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (H.A., S.K);Department of Animal and Grassland Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan (G.I., R.A.);RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan (M.K., H.S.); andRIKEN BioResource Center, Koyadai, Tsukuba, Ibaraki 305-0074, Japan (N.G.)
| | - Hiromitsu Araki
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan (K.M., J.N., S.T., M.H.-S., K.I.);Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (H.A., S.K);Department of Animal and Grassland Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan (G.I., R.A.);RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan (M.K., H.S.); andRIKEN BioResource Center, Koyadai, Tsukuba, Ibaraki 305-0074, Japan (N.G.)
| | - Satoru Kuhara
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan (K.M., J.N., S.T., M.H.-S., K.I.);Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (H.A., S.K);Department of Animal and Grassland Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan (G.I., R.A.);RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan (M.K., H.S.); andRIKEN BioResource Center, Koyadai, Tsukuba, Ibaraki 305-0074, Japan (N.G.)
| | - Genki Ishigaki
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan (K.M., J.N., S.T., M.H.-S., K.I.);Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (H.A., S.K);Department of Animal and Grassland Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan (G.I., R.A.);RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan (M.K., H.S.); andRIKEN BioResource Center, Koyadai, Tsukuba, Ibaraki 305-0074, Japan (N.G.)
| | - Ryo Akashi
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan (K.M., J.N., S.T., M.H.-S., K.I.);Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (H.A., S.K);Department of Animal and Grassland Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan (G.I., R.A.);RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan (M.K., H.S.); andRIKEN BioResource Center, Koyadai, Tsukuba, Ibaraki 305-0074, Japan (N.G.)
| | - Juntaro Negi
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan (K.M., J.N., S.T., M.H.-S., K.I.);Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (H.A., S.K);Department of Animal and Grassland Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan (G.I., R.A.);RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan (M.K., H.S.); andRIKEN BioResource Center, Koyadai, Tsukuba, Ibaraki 305-0074, Japan (N.G.)
| | - Mikiko Kojima
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan (K.M., J.N., S.T., M.H.-S., K.I.);Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (H.A., S.K);Department of Animal and Grassland Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan (G.I., R.A.);RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan (M.K., H.S.); andRIKEN BioResource Center, Koyadai, Tsukuba, Ibaraki 305-0074, Japan (N.G.)
| | - Hitoshi Sakakibara
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan (K.M., J.N., S.T., M.H.-S., K.I.);Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (H.A., S.K);Department of Animal and Grassland Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan (G.I., R.A.);RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan (M.K., H.S.); andRIKEN BioResource Center, Koyadai, Tsukuba, Ibaraki 305-0074, Japan (N.G.)
| | - Sho Takahashi
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan (K.M., J.N., S.T., M.H.-S., K.I.);Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (H.A., S.K);Department of Animal and Grassland Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan (G.I., R.A.);RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan (M.K., H.S.); andRIKEN BioResource Center, Koyadai, Tsukuba, Ibaraki 305-0074, Japan (N.G.)
| | - Mimi Hashimoto-Sugimoto
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan (K.M., J.N., S.T., M.H.-S., K.I.);Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (H.A., S.K);Department of Animal and Grassland Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan (G.I., R.A.);RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan (M.K., H.S.); andRIKEN BioResource Center, Koyadai, Tsukuba, Ibaraki 305-0074, Japan (N.G.)
| | - Nobuharu Goto
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan (K.M., J.N., S.T., M.H.-S., K.I.);Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (H.A., S.K);Department of Animal and Grassland Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan (G.I., R.A.);RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan (M.K., H.S.); andRIKEN BioResource Center, Koyadai, Tsukuba, Ibaraki 305-0074, Japan (N.G.)
| | - Koh Iba
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan (K.M., J.N., S.T., M.H.-S., K.I.);Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (H.A., S.K);Department of Animal and Grassland Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan (G.I., R.A.);RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan (M.K., H.S.); andRIKEN BioResource Center, Koyadai, Tsukuba, Ibaraki 305-0074, Japan (N.G.)
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Engineer CB, Hashimoto-Sugimoto M, Negi J, Israelsson-Nordström M, Azoulay-Shemer T, Rappel WJ, Iba K, Schroeder JI. CO2 Sensing and CO2 Regulation of Stomatal Conductance: Advances and Open Questions. TRENDS IN PLANT SCIENCE 2016; 21:16-30. [PMID: 26482956 PMCID: PMC4707055 DOI: 10.1016/j.tplants.2015.08.014] [Citation(s) in RCA: 133] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 08/24/2015] [Accepted: 08/27/2015] [Indexed: 05/18/2023]
Abstract
Guard cells form epidermal stomatal gas-exchange valves in plants and regulate the aperture of stomatal pores in response to changes in the carbon dioxide (CO2) concentration ([CO2]) in leaves. Moreover, the development of stomata is repressed by elevated CO2 in diverse plant species. Evidence suggests that plants can sense [CO2] changes via guard cells and via mesophyll tissues in mediating stomatal movements. We review new discoveries and open questions on mechanisms mediating CO2-regulated stomatal movements and CO2 modulation of stomatal development, which together function in the CO2 regulation of stomatal conductance and gas exchange in plants. Research in this area is timely in light of the necessity of selecting and developing crop cultivars that perform better in a shifting climate.
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Affiliation(s)
- Cawas B Engineer
- Division of Biological Sciences, Cell and Developmental Biology Section and Center for Food & Fuel for the 21st Century, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA
| | - Mimi Hashimoto-Sugimoto
- Department of Biology, Faculty of Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Juntaro Negi
- Department of Biology, Faculty of Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Maria Israelsson-Nordström
- Umeå Plant Science Center, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 83 Umeå, Sweden
| | - Tamar Azoulay-Shemer
- Division of Biological Sciences, Cell and Developmental Biology Section and Center for Food & Fuel for the 21st Century, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA
| | - Wouter-Jan Rappel
- Division of Biological Sciences, Cell and Developmental Biology Section and Center for Food & Fuel for the 21st Century, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA
| | - Koh Iba
- Department of Biology, Faculty of Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Julian I Schroeder
- Division of Biological Sciences, Cell and Developmental Biology Section and Center for Food & Fuel for the 21st Century, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA.
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