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Ayaz A, Gu Y. Macromorphological and foliar epidermal anatomical characteristics of Lilium rosthornii (Liliaceae): Implications for morphological adaptations and taxonomic significance. Microsc Res Tech 2024. [PMID: 38623772 DOI: 10.1002/jemt.24577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2023] [Revised: 04/02/2024] [Accepted: 04/09/2024] [Indexed: 04/17/2024]
Abstract
This research is to examine the macromorphological and foliar epidermal anatomical features of Lilium rosthornii Diels and its ability to plastically adapt to environmental forces, which is crucial for its taxonomic classification. L. rosthornii has macromorphological characteristics such as linear to lanceolate leaves of up to 20 cm in length and 2-3 cm in breadth, grouped in a whorled pattern. The blooms are voluminous and conspicuous, measuring up to 15 cm in diameter and are supported by a towering stalk that grows up to 1 m in height. The foliar epidermal structure of L. rosthornii exhibits a stomatal length of 82.02 ± 5.77 μm and a width of 29.19 ± 1.39 μm. These measurements suggest that the plant's stomata are influenced by its ploidy levels and may serve as adaptive mechanisms to enhance water consumption efficiency. The leaf structure shows a significant thickness of 398.74 ± 97.96 μm, which might potentially contribute to its ability to withstand environmental challenges. Additionally, the presence of defensive adaptations in the top and lower epidermal layers further supports this observation. The palisade tissue measurement (58.87 ± 9.56 m) and spongy tissue measurement (32.42 ± 12.72 μm) indicate a potential for photosynthetic optimization. Furthermore, there is a possible correlation between the vascular bundle width (28.15 ± 6.52 °m) and the efficiency of nutrition delivery. The results of this study emphasize the notable diversity in the foliar structures of L. rosthornii, offering valuable understanding of its morphological adaptations that have ecological and taxonomic significance. The findings provide a deeper comprehension of the potential impact of anatomical characteristics on plant function and categorization, hence providing significant insights to the domain of plant morphology and systematics. RESEARCH HIGHLIGHTS: Examines Lilium rosthornii's anatomical features and environmental adaptability for taxonomic relevance. Leaf thickness and epidermal defenses indicate resilience to environmental stress. Highlights the diversity in L. rosthornii's foliar structures, with implications for ecological and taxonomic significance Offers insights into the impact of anatomical characteristics on plant function and classification.
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Affiliation(s)
- Asma Ayaz
- Faculty of Sports Science, Ningbo University, Ningbo, China
| | - Yaodong Gu
- Faculty of Sports Science, Ningbo University, Ningbo, China
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Yoshiyama Y, Wakabayashi Y, Mercer KL, Kawabata S, Kobayashi T, Tabuchi T, Yamori W. Natural genetic variation in dynamic photosynthesis is correlated with stomatal anatomical traits in diverse tomato species across geographical habitats. J Exp Bot 2024:erae082. [PMID: 38606772 DOI: 10.1093/jxb/erae082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 02/23/2024] [Indexed: 04/13/2024]
Abstract
Plants grown under field conditions experience fluctuating light. Understanding the natural genetic variations for a similarly dynamic photosynthetic response among untapped germplasm resources, as well as the underlying mechanisms, may offer breeding strategies to improve production using molecular approaches. Here, we measured gas exchange under fluctuating light, along with stomatal density and size, in eight wild tomato species and two tomato cultivars. The photosynthetic induction response showed significant diversity, with some wild species having faster induction rates than the two cultivars. Species with faster photosynthetic induction rates had higher daily integrated photosynthesis, but lower average water use efficiency because of high stomatal conductance under natural fluctuating light. The variation in photosynthetic induction was closely associated with the speed of stomatal responses, highlighting its critical role in maximizing photosynthesis under fluctuating light conditions. Moreover, stomatal size was negatively correlated with stomatal density within a species, and plants with smaller stomata at a higher density had a quicker photosynthetic response than those with larger stomata at lower density. Our findings show that the response of stomatal conductance plays a pivotal role in photosynthetic induction, with smaller stomata at higher density proving advantageous for photosynthesis under fluctuating light in tomato species. The interspecific variation in the rate of stomatal responses could offer an untapped resource for optimizing dynamic photosynthetic responses under field conditions.
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Affiliation(s)
- Yugo Yoshiyama
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Nishitokyo, Tokyo, Japan
| | - Yu Wakabayashi
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Nishitokyo, Tokyo, Japan
| | - Kristin L Mercer
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Nishitokyo, Tokyo, Japan
- Ohio State University, Department of Horticulture and Crop Science, Columbus, OH, USA
| | - Saneyuki Kawabata
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Nishitokyo, Tokyo, Japan
| | - Takayuki Kobayashi
- Department of Advanced Food Sciences, College of Agriculture, Tamagawa University, Machida, Tokyo, Japan
| | - Toshihito Tabuchi
- Department of Advanced Food Sciences, College of Agriculture, Tamagawa University, Machida, Tokyo, Japan
| | - Wataru Yamori
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Nishitokyo, Tokyo, Japan
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Herrera JC, Savoi S, Dostal J, Elezovic K, Chatzisavva M, Forneck A, Savi T. The legacy of past droughts induces water-sparingly behaviour in Grüner Veltliner grapevines. Plant Biol (Stuttg) 2024. [PMID: 38315499 DOI: 10.1111/plb.13620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 01/08/2024] [Indexed: 02/07/2024]
Abstract
Drought is becoming more frequent and severe in numerous wine-growing regions. Nevertheless, limited research has examined the legacy of recurrent droughts, focusing on leaf physiology and anatomy over consecutive seasons. We investigated drought legacies (after 2 years of drought exposure) in potted grapevines, focusing on stomatal behaviour under well-watered conditions during the third year. Vines were subjected for two consecutive years to short- (SD) or long-term (LD) seasonal droughts, or well-watered conditions (WW). In the third year, all plants were grown without water limitation. Water potential and gas exchange were monitored throughout the three seasons, while leaf morpho-anatomical traits were measured at the end of the third year. During droughts (1st and 2nd year), stem water potential of SD and LD plants fell below -1.1 MPa, with a consequent 75% reduction in stomatal conductance (gs ) compared to WW. In the 3rd year, when all vines were daily irrigated to soil capacity (midday stem water potential ~ -0.3 MPa), 45% lower values of gs were observed in the ex-LD group compared to both ex-SD and ex-WW. Reduced midrib vessel diameter, lower leaf theoretical hydraulic conductivity, and smaller stomata were measured in ex-LD leaves compared to ex-SD and ex-WW, likely contributing to the reduced gas exchange. Our findings suggest that grapevines exposed to drought may adopt a more water-conserving strategy in subsequent seasons, irrespective of current soil water availability, with the degree of change influenced by the intensity and duration of past drought events.
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Affiliation(s)
- J C Herrera
- Department of Crop Sciences, Institute of Viticulture and Pomology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - S Savoi
- Department of Agricultural, Forest and Food Sciences, University of Turin, Grugliasco, Italy
| | - J Dostal
- Department of Crop Sciences, Institute of Viticulture and Pomology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - K Elezovic
- Department of Crop Sciences, Institute of Viticulture and Pomology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - M Chatzisavva
- Department of Crop Sciences, Institute of Viticulture and Pomology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - A Forneck
- Department of Crop Sciences, Institute of Viticulture and Pomology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - T Savi
- Department of Integrative Biology and Biodiversity Research, Institute of Botany, University of Natural Resources and Life Sciences, Vienna, Austria
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Al-Salman Y, Cano FJ, Pan L, Koller F, Piñeiro J, Jordan D, Ghannoum O. Anatomical drivers of stomatal conductance in sorghum lines with different leaf widths grown under different temperatures. Plant Cell Environ 2023; 46:2142-2158. [PMID: 37066624 DOI: 10.1111/pce.14592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 03/29/2023] [Accepted: 04/03/2023] [Indexed: 06/08/2023]
Abstract
Sustaining crop productivity and resilience in water-limited environments and under rising temperatures are matters of concern worldwide. We investigated the leaf anatomical traits that underpin our recently identified link between leaf width (LW) and intrinsic water use efficiency (iWUE), as traits of interest in plant breeding. Ten sorghum lines with varying LW were grown under three temperatures to expand the range of variation of both LW and gas exchange rates. Leaf gas exchange, surface morphology and cross-sectional anatomy were measured and analysed using structural equations modelling. Narrower leaves had lower stomatal conductance (gs ) and higher iWUE across growth temperatures. They also had smaller intercellular airspaces, stomatal size, percentage of open stomatal aperture relative to maximum, hydraulic pathway, mesophyll thickness, and leaf mass per area. Structural modelling revealed a developmental association among leaf anatomical traits that underpinned gs variation in sorghum. Growing temperature and LW both impacted leaf gas exchange rates, but only LW directly impacted leaf anatomy. Wider leaves may be more productive under well-watered conditions, but consume more water for growth and development, which is detrimental under water stress.
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Affiliation(s)
- Yazen Al-Salman
- ARC Centre of Excellence for Translational Photosynthesis, Canberra, ACT, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia
| | - Francisco J Cano
- ARC Centre of Excellence for Translational Photosynthesis, Canberra, ACT, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia
- Instituto de Ciencias Forestales (ICIFOR-INIA), CSIC, Madrid, Spain
| | - Ling Pan
- ARC Centre of Excellence for Translational Photosynthesis, Canberra, ACT, Australia
- Department of Grassland Science, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
- College of Animal Science and Technology, Yangzhou University, Yangzhou, China
| | - Fiona Koller
- ARC Centre of Excellence for Translational Photosynthesis, Canberra, ACT, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia
| | - Juan Piñeiro
- Department of Biology, IVAGRO, Campus de Excelencia Internacional Agroalimentario, Capus del Rio San Pedro, University of Cádiz, Puerto Real, Spain
| | - David Jordan
- ARC Centre of Excellence for Translational Photosynthesis, Canberra, ACT, Australia
- Hermitage Research Facility, The University of Queensland, Warwick, Queensland, Australia
- Agri-Science Queensland, Department of Agriculture & Fisheries, Hermitage Research Facility, Warwick, Queensland, Australia
| | - Oula Ghannoum
- ARC Centre of Excellence for Translational Photosynthesis, Canberra, ACT, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia
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Lei Z, He Y, Li X, He Z, Zhang Y, Zhang W, Liu F, Zhang Y. Domestication has reduced leaf water use efficiency associated with the anatomy of abaxial stomata in cotton. J Exp Bot 2023; 74:878-888. [PMID: 36385641 DOI: 10.1093/jxb/erac447] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 11/11/2022] [Indexed: 06/16/2023]
Abstract
Crop domestication for increasing growth rates and yields appears to have altered the features of adaxial and abaxial stomata, but its effect on leaf water use efficiency (WUE) have not been experimentally verified. In this study, we characterized stomatal anatomy and carbon isotope discrimination (δ13C) in 32 wild and 36 domesticated genotypes of cotton grown under agricultural field conditions. The results showed that domesticated genotypes possessed lower WUE, as indicated by low or more negative δ13C compared with wild genotypes. Higher theoretical maximum stomatal conductance (gsmax) after domestication was accounted for by more stomata rather than significantly enlarged stomata. Specifically, abaxial stomatal density was higher whilst there was no change in the adaxial density. The size of both adaxial and abaxial stomata was greater due to larger guard cells but without there being any increase in pore size. However, there was a negative relationship between δ13C and stomatal size across wild and domesticated genotypes, especially on the abaxial leaf surface, because bigger stomata resulted in a lower maximum stomatal response rate to fluctuating canopy light, resulting in increased water loss. Overall, our results indicate that cotton domestication has resulted in substantial variation in stomatal anatomy, and that WUE and drought tolerance can potentially be improved in future breeding by decreasing the size of abaxial stomata to produce a faster stomatal response and hence a reduction in unnecessary water loss.
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Affiliation(s)
- Zhangying Lei
- Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Corps, Shihezi University, Shihezi, 832003, P.R. China
| | - Yang He
- Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Corps, Shihezi University, Shihezi, 832003, P.R. China
| | - Xiafei Li
- Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Corps, Shihezi University, Shihezi, 832003, P.R. China
| | - Ziqi He
- Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Corps, Shihezi University, Shihezi, 832003, P.R. China
| | - Yujie Zhang
- Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Corps, Shihezi University, Shihezi, 832003, P.R. China
| | - Wangfeng Zhang
- Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Corps, Shihezi University, Shihezi, 832003, P.R. China
| | - Fang Liu
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, P.R. China
| | - Yali Zhang
- Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Corps, Shihezi University, Shihezi, 832003, P.R. China
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Petrik P, Petek-Petrik A, Kurjak D, Mukarram M, Klein T, Gömöry D, Střelcová K, Frýdl J, Konôpková A. Interannual adjustments in stomatal and leaf morphological traits of European beech (Fagus sylvatica L.) demonstrate its climate change acclimation potential. Plant Biol (Stuttg) 2022; 24:1287-1296. [PMID: 35238138 DOI: 10.1111/plb.13401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 01/27/2022] [Indexed: 06/14/2023]
Abstract
The current projections of climate change might exceed the ability of European forest trees to adapt to upcoming environmental conditions. However, stomatal and leaf morphological traits could greatly influence the acclimation potential of forest tree species subjected to global warming, including the single most important forestry species in Europe, European beech. We analysed stomatal (guard cell length, stomatal density and potential conductance index) and leaf (leaf area, leaf dry weight and leaf mass per area) morphological traits of ten provenances from two provenance trials with contrasting climates between 2016 and 2020. The impact of meteorological conditions of the current and preceding year on stomatal and leaf traits was tested by linear and quadratic regressions. Ecodistance was used to capture the impact of adaptation after the transfer of provenances to new environments. Interactions of trial-provenance and trial-year factors were significant for all measured traits. Guard cell length was lowest and stomatal density was highest across beech provenances in the driest year, 2018. Adaptation was also reflected in a significant relationship between aridity ecodistance and measured traits. Moreover, the meteorological conditions of the preceding year affected the interannual variability of stomatal and leaf traits more than the meteorological conditions of the spring of the current year, suggesting the existence of plant stress memory. High intraspecific variability of stomatal and leaf traits controlled by the interaction of adaptation, acclimation and plant memory suggests a high acclimation potential of European beech provenances under future conditions of global climate change.
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Affiliation(s)
- P Petrik
- Global Change Research Institute, Czech Academy of Sciences, Brno, Czech Republic
| | - A Petek-Petrik
- Department of Vegetation Ecology, Institute of Botany CAS, Brno, Czech Republic
| | - D Kurjak
- Faculty of Forestry, Technical University in Zvolen, Zvolen, Slovakia
| | - M Mukarram
- Faculty of Forestry, Technical University in Zvolen, Zvolen, Slovakia
- Advance Plant Physiology Section, Department of Botany, Aligarh Muslim University, Aligarh, India
| | - T Klein
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - D Gömöry
- Faculty of Forestry, Technical University in Zvolen, Zvolen, Slovakia
| | - K Střelcová
- Faculty of Forestry, Technical University in Zvolen, Zvolen, Slovakia
| | - J Frýdl
- Forestry and Game Management Research Institute, Jíloviště, Czech Republic
| | - A Konôpková
- Faculty of Forestry, Technical University in Zvolen, Zvolen, Slovakia
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Toda Y, Tameshige T, Tomiyama M, Kinoshita T, Shimizu KK. Corrigendum: An Affordable Image-Analysis Platform to Accelerate Stomatal Phenotyping During Microscopic Observation. Front Plant Sci 2021; 12:793369. [PMID: 34804109 PMCID: PMC8595934 DOI: 10.3389/fpls.2021.793369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 10/14/2021] [Indexed: 06/13/2023]
Abstract
[This corrects the article DOI: 10.3389/fpls.2021.715309.].
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Affiliation(s)
- Yosuke Toda
- Japan Science and Technology Agency, Saitama, Japan
- Phytometrics co., ltd., Shizuoka, Japan
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Nagoya, Japan
| | - Toshiaki Tameshige
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Japan
- Department of Biology, Faculty of Science, Niigata University, Niigata, Japan
| | | | - Toshinori Kinoshita
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Nagoya, Japan
| | - Kentaro K. Shimizu
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Japan
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
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Toda Y, Tameshige T, Tomiyama M, Kinoshita T, Shimizu KK. An Affordable Image-Analysis Platform to Accelerate Stomatal Phenotyping During Microscopic Observation. Front Plant Sci 2021; 12:715309. [PMID: 34394171 PMCID: PMC8358771 DOI: 10.3389/fpls.2021.715309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 07/08/2021] [Indexed: 06/13/2023]
Abstract
Recent technical advances in the computer-vision domain have facilitated the development of various methods for achieving image-based quantification of stomata-related traits. However, the installation cost of such a system and the difficulties of operating it on-site have been hurdles for experimental biologists. Here, we present a platform that allows real-time stomata detection during microscopic observation. The proposed system consists of a deep neural network model-based stomata detector and an upright microscope connected to a USB camera and a graphics processing unit (GPU)-supported single-board computer. All the hardware components are commercially available at common electronic commerce stores at a reasonable price. Moreover, the machine-learning model is prepared based on freely available cloud services. This approach allows users to set up a phenotyping platform at low cost. As a proof of concept, we trained our model to detect dumbbell-shaped stomata from wheat leaf imprints. Using this platform, we collected a comprehensive range of stomatal phenotypes from wheat leaves. We confirmed notable differences in stomatal density (SD) between adaxial and abaxial surfaces and in stomatal size (SS) between wheat-related species of different ploidy. Utilizing such a platform is expected to accelerate research that involves all aspects of stomata phenotyping.
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Affiliation(s)
- Yosuke Toda
- Japan Science and Technology Agency, Saitama, Japan
- Phytometrics co., ltd., Shizuoka, Japan
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Nagoya, Japan
| | - Toshiaki Tameshige
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Japan
- Department of Biology, Faculty of Science, Niigata University, Niigata, Japan
| | | | - Toshinori Kinoshita
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Nagoya, Japan
| | - Kentaro K. Shimizu
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Japan
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
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Barratt GE, Sparkes DL, McAusland L, Murchie EH. Anisohydric sugar beet rapidly responds to light to optimize leaf water use efficiency utilizing numerous small stomata. AoB Plants 2021; 13:plaa067. [PMID: 33442465 PMCID: PMC7780706 DOI: 10.1093/aobpla/plaa067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 11/30/2020] [Indexed: 05/08/2023]
Abstract
Under conditions of high transpiration and low soil water availability, the demand for water can exceed supply causing a reduction in water potential and a loss of cell turgor (wilting). Regulation of stomatal aperture mediates the loss of water vapour (g s), which in turn is dependent in part on the anatomical characteristics of stomatal density (SD) and stomatal size (SS). Anisohydric sugar beet (Beta vulgaris) is atypical, exhibiting wilting under high soil water availability. Spinach (Spinacia oleracea) belongs to the same family Chenopodiaceae s.s., but demonstrates a more typical wilting response. To investigate the role of stomatal dynamics in such behaviours, sugar beet and spinach leaves were exposed to step-changes in photosynthetic photon flux density (PPFD) from 250 to 2500 µmol m-2 s-1. Using a four log-logistic function, the maximum rate of stomatal opening was estimated. Concurrent measurements of SD and SS were taken for both species. While sugar beet coupled faster opening with smaller, more numerous stomata, spinach showed the converse. After exposure to drought, maximum g s was reduced in sugar beet but still achieved a similar speed of opening. It is concluded that sugar beet stomata respond rapidly to changes in PPFD with a high rate and magnitude of opening under both non-droughted and droughted conditions. Such a response may contribute to wilting, even under high soil water availability, but enables photosynthesis to be better coupled with increasing PPFD.
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Affiliation(s)
| | - Debbie L Sparkes
- School of Biosciences, University of Nottingham, Loughborough, UK
| | - Lorna McAusland
- School of Biosciences, University of Nottingham, Loughborough, UK
| | - Erik H Murchie
- School of Biosciences, University of Nottingham, Loughborough, UK
- Corresponding author’s e-mail address:
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Veselý P, Šmarda P, Bureš P, Stirton C, Muasya AM, Mucina L, Horová L, Veselá K, Šilerová A, Šmerda J, Knápek O. Environmental pressures on stomatal size may drive plant genome size evolution: evidence from a natural experiment with Cape geophytes. Ann Bot 2020; 126:323-330. [PMID: 32474609 PMCID: PMC7380457 DOI: 10.1093/aob/mcaa095] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 05/21/2020] [Indexed: 05/02/2023]
Abstract
BACKGROUND AND AIMS The idea that genome (size) evolution in eukaryotes could be driven by environmental factors is still vigorously debated. In extant plants, genome size correlates positively with stomatal size, leading to the idea that conditions enabling the existence of large stomata in fossil plants also supported growth of their genome size. We test this inductive assumption in drought-adapted, prostrate-leaved Cape (South Africa) geophytes where, compared with their upright-leaved geophytic ancestors, stomata develop in a favourably humid microclimate formed underneath their leaves. METHODS Stomatal parameters (leaf cuticle imprints) and genome size (flow cytometry) were measured in 16 closely related geophytic species pairs from seven plant families. In each pair, representing a different genus, we contrasted a prostrate-leaved species with its upright-leaved phylogenetic relative, the latter whose stomata are exposed to the ambient arid climate. KEY RESULTS Except for one, all prostrate-leaves species had larger stomata, and in 13 of 16 pairs they also had larger genomes than their upright-leaved relatives. Stomatal density and theoretical maximum conductance were less in prostrate-leaved species with small guard cells (<1 pL) but showed no systematic difference in species pairs with larger guard cells (>1 pL). Giant stomata were observed in the prostrate-leaved Satyrium bicorne (89-137 µm long), despite its relatively small genome (2C = 9 Gbp). CONCLUSIONS Our results imply that climate, through selection on stomatal size, might be able to drive genome size evolution in plants. The data support the idea that plants from 'greenhouse' geological periods with large stomata might have generally had larger genome sizes when compared with extant plants, though this might not have been solely due to higher atmospheric CO2 in these periods but could also have been due to humid conditions prevailing at fossil deposit sites.
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Affiliation(s)
- Pavel Veselý
- Department of Botany and Zoology, Masaryk University, Kotlářská, Brno, Czech Republic
| | - Petr Šmarda
- Department of Botany and Zoology, Masaryk University, Kotlářská, Brno, Czech Republic
- For correspondence. E-mail
| | - Petr Bureš
- Department of Botany and Zoology, Masaryk University, Kotlářská, Brno, Czech Republic
| | - Charles Stirton
- Bolus Herbarium, Department of Biological Sciences, University of Cape Town, Rondebosch, Cape Town, South Africa
| | - A Muthama Muasya
- Bolus Herbarium, Department of Biological Sciences, University of Cape Town, Rondebosch, Cape Town, South Africa
| | - Ladislav Mucina
- Iluka Chair in Vegetation Science and Biogeography, Harry Butler Institute, Murdoch University, Murdoch, Perth, Australia
- Department of Geography and Environmental Studies, Stellenbosch University, Matieland, Stellenbosch, South Africa
| | - Lucie Horová
- Department of Botany and Zoology, Masaryk University, Kotlářská, Brno, Czech Republic
| | - Kristýna Veselá
- Department of Botany and Zoology, Masaryk University, Kotlářská, Brno, Czech Republic
| | - Alexandra Šilerová
- Department of Botany and Zoology, Masaryk University, Kotlářská, Brno, Czech Republic
| | - Jakub Šmerda
- Department of Botany and Zoology, Masaryk University, Kotlářská, Brno, Czech Republic
| | - Ondřej Knápek
- Department of Botany and Zoology, Masaryk University, Kotlářská, Brno, Czech Republic
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Chen H, Zhao X, Zhai L, Shao K, Jiang K, Shen C, Chen K, Wang S, Wang Y, Xu J. Genetic Bases of the Stomata-Related Traits Revealed by a Genome-Wide Association Analysis in Rice ( Oryza sativa L.). Front Genet 2020; 11:611. [PMID: 32582301 PMCID: PMC7296080 DOI: 10.3389/fgene.2020.00611] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 05/19/2020] [Indexed: 12/13/2022] Open
Abstract
Stomatal density (D) and size (S) are an important adaptive mechanism for abiotic stress tolerance and photosynthesis capacity in rice. However, the genetic base of rice stomata-related traits still remains unclear. We identified quantitative trait loci (QTLs) associated with D and S on abaxial and adaxial leaf surfaces using genome-wide association analysis with 451 diverse accessions in two environments. D and S showed significant differences between indica (xian) and japonica (geng) accessions and significantly negative phenotypic correlations. A total of 64 QTLs influencing eight stomata-related traits were identified using 2,936,762 high-quality single nucleotide polymorphism markers. Twelve QTLs were consistently detected for the same traits in nine chromosomal regions in both environments. In addition, 12 QTL clusters were simultaneously detected for the same stomata-related traits on abaxial and adaxial leaf surfaces in the same environment, probably explaining the genetic bases of significant correlations of the stomata-related traits. We screened 64 candidate genes for the nine consistent QTL regions using haplotype analysis. Among them, LOC_Os01g66120 for qD ada 1, OsSPCH2 (LOC_Os02g15760) for qD ada 2.1 and qD aba 2.1, LOC_Os02g34320 for qS ada 2.2, OsFLP (LOC_Os07g43420) or LOC_Os07g43530 for qS aba 7.1, and LOC_Os07g41200 for qW ada 7 and qW aba 7 were considered as the most likely candidate genes based on functional annotations. The results systematically dissected the genetic base of stomata-related traits and provide useful information for improving rice yield potential via increasing abiotic stress tolerance and photosynthesis capacity under stressed and non-stressed conditions through deploying the favorable alleles underlying stomata-related traits by marker-assisted selection.
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Affiliation(s)
- Hongwei Chen
- Rice Research Institute, Shenyang Agricultural University, Shenyang, China
| | - Xiuqin Zhao
- Institute of Crop Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Laiyuan Zhai
- Rice Research Institute, Shenyang Agricultural University, Shenyang, China
- Institute of Crop Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Kuitian Shao
- Rice Research Institute, Shenyang Agricultural University, Shenyang, China
| | - Kunwei Jiang
- Rice Research Institute, Shenyang Agricultural University, Shenyang, China
| | - Congcong Shen
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Kai Chen
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Shu Wang
- Rice Research Institute, Shenyang Agricultural University, Shenyang, China
| | - Yun Wang
- Rice Research Institute, Shenyang Agricultural University, Shenyang, China
| | - Jianlong Xu
- Institute of Crop Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Chinese Academy of Agricultural Sciences, Beijing, China
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Zhang Q, Peng S, Li Y. Increase rate of light-induced stomatal conductance is related to stomatal size in the genus Oryza. J Exp Bot 2019; 70:5259-5269. [PMID: 31145797 PMCID: PMC6793446 DOI: 10.1093/jxb/erz267] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 05/22/2019] [Indexed: 05/02/2023]
Abstract
The rapid response of stomatal conductance (gs) to fluctuating irradiance is of great importance to maximize carbon assimilation while minimizing water loss. Smaller stomata have been proven to have a faster response rate than larger ones, but most of these studies have been conducted with forest trees. In the present study, the effects of stomatal anatomy on the kinetics of gs and photosynthesis were investigated in 16 Oryza genotypes. Light-induced stomatal opening includes an initial time lag (λ) followed by an exponential increase. Smaller stomata had a larger maximum stomatal conductance increase rate (Slmax) during the exponential increase phase, but showed a longer time lag and a lower initial stomatal conductance (gs,initial) at low light. Stomatal size was, surprisingly, negatively correlated with the time required to reach 50% of maximum gs and photosynthesis (T50%gs and T50%A), which was shown to be positively correlated with λ and negatively correlated with gs,initial. With a lower gs,initial and a larger λ, small stomata showed a faster decrease of intercellular CO2 concentration (Ci) during the induction process, which may have led to a slower apparent Rubisco activation rate. Therefore, smaller stomata do not always benefit photosynthesis as reported before; the influence of stomatal size on dynamic photosynthesis is also correlated with λ and gs,initial.
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Affiliation(s)
- Qiangqiang Zhang
- National Key Laboratory of Crop Genetic Improvement, Ministry of Agriculture Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Shaobing Peng
- National Key Laboratory of Crop Genetic Improvement, Ministry of Agriculture Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
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13
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Affiliation(s)
- Petr Šmarda
- Department of Botany and Zoology, Masaryk University, Kotlářská 2, CZ-61137, Brno, Czech Republic
| | - Pavel Veselý
- Department of Botany and Zoology, Masaryk University, Kotlářská 2, CZ-61137, Brno, Czech Republic
| | - Jakub Šmerda
- Department of Botany and Zoology, Masaryk University, Kotlářská 2, CZ-61137, Brno, Czech Republic
| | - Petr Bureš
- Department of Botany and Zoology, Masaryk University, Kotlářská 2, CZ-61137, Brno, Czech Republic
| | - Ondřej Knápek
- Department of Botany and Zoology, Masaryk University, Kotlářská 2, CZ-61137, Brno, Czech Republic
| | - Magdaléna Chytrá
- Botanical Garden of the Faculty of Science, Masaryk University, Kotlářská 2, CZ-61137, Brno, Czech Republic
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14
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Elliott-Kingston C, Haworth M, Yearsley JM, Batke SP, Lawson T, McElwain JC. Does Size Matter? Atmospheric CO2 May Be a Stronger Driver of Stomatal Closing Rate Than Stomatal Size in Taxa That Diversified under Low CO2. Front Plant Sci 2016; 7:1253. [PMID: 27605929 PMCID: PMC4996050 DOI: 10.3389/fpls.2016.01253] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 08/08/2016] [Indexed: 05/02/2023]
Abstract
One strategy for plants to optimize stomatal function is to open and close their stomata quickly in response to environmental signals. It is generally assumed that small stomata can alter aperture faster than large stomata. We tested the hypothesis that species with small stomata close faster than species with larger stomata in response to darkness by comparing rate of stomatal closure across an evolutionary range of species including ferns, cycads, conifers, and angiosperms under controlled ambient conditions (380 ppm CO2; 20.9% O2). The two species with fastest half-closure time and the two species with slowest half-closure time had large stomata while the remaining three species had small stomata, implying that closing rate was not correlated with stomatal size in these species. Neither was response time correlated with stomatal density, phylogeny, functional group, or life strategy. Our results suggest that past atmospheric CO2 concentration during time of taxa diversification may influence stomatal response time. We show that species which last diversified under low or declining atmospheric CO2 concentration close stomata faster than species that last diversified in a high CO2 world. Low atmospheric [CO2] during taxa diversification may have placed a selection pressure on plants to accelerate stomatal closing to maintain adequate internal CO2 and optimize water use efficiency.
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Affiliation(s)
| | - Matthew Haworth
- Italian National Research Council, Institute of Tree and Timber IVALSARome, Italy
| | - Jon M. Yearsley
- Earth Institute, Science Centre East, School of Biology and Environmental Science, University College DublinDublin, Ireland
| | - Sven P. Batke
- Earth Institute, Science Centre East, School of Biology and Environmental Science, University College DublinDublin, Ireland
| | - Tracy Lawson
- School of Biological Science, University of EssexColchester, UK
| | - Jennifer C. McElwain
- Earth Institute, Science Centre East, School of Biology and Environmental Science, University College DublinDublin, Ireland
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15
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Giday H, Fanourakis D, Kjaer KH, Fomsgaard IS, Ottosen CO. Threshold response of stomatal closing ability to leaf abscisic acid concentration during growth. J Exp Bot 2014; 65:4361-70. [PMID: 24863434 PMCID: PMC4112639 DOI: 10.1093/jxb/eru216] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Leaf abscisic acid concentration ([ABA]) during growth influences morpho-physiological traits associated with the plant's ability to cope with stress. A dose-response curve between [ABA] during growth and the leaf's ability to regulate water loss during desiccation or rehydrate upon re-watering was obtained. Rosa hybrida plants were grown at two relative air humidities (RHs, 60% or 90%) under different soil water potentials (-0.01, -0.06, or -0.08MPa) or upon grafting onto the rootstock of a cultivar sustaining [ABA] at elevated RH. Measurements included [ABA], stomatal anatomical features, stomatal responsiveness to desiccation, and the ability of leaves, desiccated to varying degrees, to recover their weight (rehydrate) following re-watering. Transpiration efficiency (plant mass per transpired water) was also determined. Soil water deficit resulted in a lower transpiration rate and higher transpiration efficiency at both RHs. The lowest [ABA] was observed in well-watered plants grown at high RH. [ABA] was increased by soil water deficit or grafting, at both RHs. The growth environment-induced changes in stomatal size were mediated by [ABA]. When [ABA] was increased from the level of (well-watered) high RH-grown plants to the value of (well-watered) plants grown at moderate RH, stomatal responsiveness was proportionally improved. A further increase in [ABA] did not affect stomatal responsiveness to desiccation. [ABA] was positively related to the ability of dehydrated leaves to rehydrate. The data indicate a growth [ABA]-related threshold for stomatal sensitivity to desiccation, which was not apparent either for stomatal size or for recovery (rehydration) upon re-watering.
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Affiliation(s)
- Habtamu Giday
- Department of Food Science, Århus University, Kirstinebjergvej 10, DK-5792, Årslev, Denmark
| | - Dimitrios Fanourakis
- Institute for Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich, D-52425 Jülich, Germany
| | - Katrine H Kjaer
- Department of Food Science, Århus University, Kirstinebjergvej 10, DK-5792, Årslev, Denmark
| | - Inge S Fomsgaard
- Department of Agroecology-Crop Health, Århus University, Forsøgsvej 1, 4200 Slagelse, Denmark
| | - Carl-Otto Ottosen
- Department of Food Science, Århus University, Kirstinebjergvej 10, DK-5792, Årslev, Denmark
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16
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Abstract
Maximum and minimum stomatal conductance, as well as stomatal size and rate of response, are known to vary widely across plant species, but the functional relationship between these static and dynamic stomatal properties is unknown. The objective of this study was to test three hypotheses: (i) operating stomatal conductance under standard conditions (g (op)) correlates with minimum stomatal conductance prior to morning light [g (min(dawn))]; (ii) stomatal size (S) is negatively correlated with g (op) and the maximum rate of stomatal opening in response to light, (dg/dt)(max); and (iii) g (op) correlates negatively with instantaneous water-use efficiency (WUE) despite positive correlations with maximum rate of carboxylation (Vc (max)) and light-saturated rate of electron transport (J (max)). Using five closely related species of the genus Banksia, the above variables were measured, and it was found that all three hypotheses were supported by the results. Overall, this indicates that leaves built for higher rates of gas exchange have smaller stomata and faster dynamic characteristics. With the aid of a stomatal control model, it is demonstrated that higher g (op) can potentially expose plants to larger tissue water potential gradients, and that faster stomatal response times can help offset this risk.
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Affiliation(s)
- Paul L. Drake
- Natural Resources Branch, Department of Environment and Conservation, Locked Bag 104, Bentley Delivery Centre, WA 6983, Australia
| | - Ray H. Froend
- School of Natural Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027, Australia6027
| | - Peter J. Franks
- Faculty of Agriculture and Environment, University of Sydney, Sydney, NSW 2006
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17
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Hodgson JG, Sharafi M, Jalili A, Díaz S, Montserrat-Martí G, Palmer C, Cerabolini B, Pierce S, Hamzehee B, Asri Y, Jamzad Z, Wilson P, Raven JA, Band SR, Basconcelo S, Bogard A, Carter G, Charles M, Castro-Díez P, Cornelissen JHC, Funes G, Jones G, Khoshnevis M, Pérez-Harguindeguy N, Pérez-Rontomé MC, Shirvany FA, Vendramini F, Yazdani S, Abbas-Azimi R, Boustani S, Dehghan M, Guerrero-Campo J, Hynd A, Kowsary E, Kazemi-Saeed F, Siavash B, Villar-Salvador P, Craigie R, Naqinezhad A, Romo-Díez A, de Torres Espuny L, Simmons E. Stomatal vs. genome size in angiosperms: the somatic tail wagging the genomic dog? Ann Bot 2010; 105:573-84. [PMID: 20375204 PMCID: PMC2850795 DOI: 10.1093/aob/mcq011] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2008] [Revised: 07/04/2008] [Accepted: 12/21/2009] [Indexed: 05/02/2023]
Abstract
BACKGROUND AND AIMS Genome size is a function, and the product, of cell volume. As such it is contingent on ecological circumstance. The nature of 'this ecological circumstance' is, however, hotly debated. Here, we investigate for angiosperms whether stomatal size may be this 'missing link': the primary determinant of genome size. Stomata are crucial for photosynthesis and their size affects functional efficiency. METHODS Stomatal and leaf characteristics were measured for 1442 species from Argentina, Iran, Spain and the UK and, using PCA, some emergent ecological and taxonomic patterns identified. Subsequently, an assessment of the relationship between genome-size values obtained from the Plant DNA C-values database and measurements of stomatal size was carried out. KEY RESULTS Stomatal size is an ecologically important attribute. It varies with life-history (woody species < herbaceous species < vernal geophytes) and contributes to ecologically and physiologically important axes of leaf specialization. Moreover, it is positively correlated with genome size across a wide range of major taxa. CONCLUSIONS Stomatal size predicts genome size within angiosperms. Correlation is not, however, proof of causality and here our interpretation is hampered by unexpected deficiencies in the scientific literature. Firstly, there are discrepancies between our own observations and established ideas about the ecological significance of stomatal size; very large stomata, theoretically facilitating photosynthesis in deep shade, were, in this study (and in other studies), primarily associated with vernal geophytes of unshaded habitats. Secondly, the lower size limit at which stomata can function efficiently, and the ecological circumstances under which these minute stomata might occur, have not been satisfactorally resolved. Thus, our hypothesis, that the optimization of stomatal size for functional efficiency is a major ecological determinant of genome size, remains unproven.
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Affiliation(s)
- J G Hodgson
- Peak Science and Environment, Station House, Leadmill, Hathersage, Hope Valley S32 1BA, UK.
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18
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Kouwenberg LLR, Kürschner WM, Visscher H. Changes in stomatal frequency and size during elongation of Tsuga heterophylla needles. Ann Bot 2004; 94:561-9. [PMID: 15321836 PMCID: PMC4242229 DOI: 10.1093/aob/mch175] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2004] [Revised: 06/08/2004] [Accepted: 06/25/2004] [Indexed: 05/24/2023]
Abstract
BACKGROUND AND AIMS The inverse relationship between the number of stomata and atmospheric CO2 levels observed in different plant species is increasingly used for reconstructions of past CO2 concentrations. To validate this relationship, the potential influence of other environmental conditions and ontogenetical development stage on stomatal densities must be investigated as well. Quantitative data on the changes in stomatal density of conifers in relation to leaf development is reported. METHODS Stomatal frequency and epidermal cells of Tsuga heterophylla needles during different stages of budburst were measured using computerized image analysis systems on light microscope slides. KEY RESULTS Stomata first appear in the apical region and subsequently spread basipetally towards the needle base during development. The number of stomatal rows on a needle does not change during ontogeny, but stomatal density decreases nonlinearly with increasing needle area, until about 50 % of the final needle area. The total number of stomata on the needle increases during the entire developmental period, indicating that stomatal and epidermal cell formation continues until the needle has matured completely. CONCLUSIONS Epidermal characteristics in developing conifer needles appear to be fundamentally different from angiosperm dicot leaves, where in general leaf expansion in the final stages is due to cell expansion rather than cell formation. The lack of further change in either stomatal density or stomatal density per millimetre needle length (the stomatal characteristic most sensitive to CO2 in conifers) in the final stages of leaf growth indicates that in conifers the stage of leaf maturation would not influence CO2 reconstructions based on stomatal density.
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Affiliation(s)
- Lenny L R Kouwenberg
- Department of Palaeoecology, Laboratory of Palaeobotany and Palynology, Utrecht University, Budapestlaan 4, 3584 CD, The Netherlands.
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