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Ming X, Chen X, Ma H, Li C, Zhao Z, Li J, Du Y. The fertility tracks of pollen tube in the ovary of Solanum nigrum by three-dimensional reconstruction. J Microsc 2024; 293:86-97. [PMID: 38108660 DOI: 10.1111/jmi.13257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 12/13/2023] [Accepted: 12/14/2023] [Indexed: 12/19/2023]
Abstract
In this paper, we present an enhanced method for automatically capturing a large number of consecutive paraffin sections using a microscope. Leveraging these microstructural images, we employed three-dimensional visualisation and reconstruction techniques to investigate the dispersal growth process of pollen tube bundles upon entering the ovary of Solanum nigrum. Additionally, we explored their behaviour within different ovules and examined the relationship between the germination rate of seeds and the fertilisation process. Our findings reveal that despite the abundance of Solanum nigrum seeds, only a fraction of them is capable of successful germination. The germination rate of seeds is closely related to whether fertilisation of the ovules and pollen tubes is completed. Due to the limited number of pollen tubes entering the ovary, only a portion of the ovules can be fertilised. The proportion of fertilised ovules positively correlates with the germination rate of the seeds. Through three-dimensional reconstruction, we observed a phenomenon of proximity during the pollination process, wherein ovules closer to the pollen tube bundles are more likely to be fertilised. Furthermore, fertilised ovules exhibited significant changes in morphology and embryo sac structure. The number of fertilised ovules directly impacts the germination rate of wild Solanum nigrum seeds. Although all Solanum nigrum ovules have the potential to develop into seeds, most seeds originating from unfertilised ovules are unable to germinate normally, resulting in an incomplete germination rate of seeds and preventing it from reaching 100%.
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Affiliation(s)
- Xing Ming
- National & Local United Engineering Laboratory for Chinese Herbal Medicine Breeding and Cultivation, School of Life Sciences, Jilin University, Changchun, Jilin, China
| | - Xia Chen
- National & Local United Engineering Laboratory for Chinese Herbal Medicine Breeding and Cultivation, School of Life Sciences, Jilin University, Changchun, Jilin, China
| | - Hongyu Ma
- Jilin Provincial Joint Key Laboratory of Changbai Mountain Biocoenosis and Biodiversity, Academy of Science of Changbai Mountain, Yanbian, Jilin, China
| | - Chuang Li
- Institute of Economic Botany, Jilin Academy of Agricultural Sciences, Changchun, Jilin, China
| | - Zijian Zhao
- National & Local United Engineering Laboratory for Chinese Herbal Medicine Breeding and Cultivation, School of Life Sciences, Jilin University, Changchun, Jilin, China
| | - Jinying Li
- National & Local United Engineering Laboratory for Chinese Herbal Medicine Breeding and Cultivation, School of Life Sciences, Jilin University, Changchun, Jilin, China
| | - Yingda Du
- School of Life Sciences, Jilin University, Changchun, Jilin, China
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2
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Leménager M, Burkiewicz J, Schoen DJ, Joly S. Studying flowers in 3D using photogrammetry. THE NEW PHYTOLOGIST 2023; 237:1922-1933. [PMID: 36263728 DOI: 10.1111/nph.18553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 09/28/2022] [Indexed: 06/16/2023]
Abstract
Flowers are intricate and integrated three-dimensional (3D) structures predominantly studied in 2D due to the difficulty in quantitatively characterising their morphology in 3D. Given the recent development of analytical methods for high-dimensional data, the reconstruction of flower models in three dimensions represents the limiting factor to studying flowers in 3D. We developed a floral photogrammetry protocol to reconstruct 3D models of flowers based on images taken with a digital single-lens reflex camera, a turntable and a portable lightbox. We demonstrate that photogrammetry allows a rapid and accurate reconstruction of 3D models of flowers from 2D images. It can reconstruct all visible parts of flowers and has the advantage of keeping colour information. We illustrated its use by studying the shape and colour of 18 Gesneriaceae species. Photogrammetry is an affordable alternative to micro-computed tomography (micro-CT) that requires minimal investment and equipment, allowing it to be used directly in the field. It has the potential to stimulate research on the evolution and ecology of flowers by providing a simple way to access 3D morphological data from a variety of flower types.
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Affiliation(s)
- Marion Leménager
- Département de Sciences Biologiques, Institut de Recherche en Biologie Végétale, Université de Montréal, 4101 Rue Sherbrooke E, Montréal, QC, H1X 2B2, Canada
| | - Jérôme Burkiewicz
- Département de Sciences Biologiques, Institut de Recherche en Biologie Végétale, Université de Montréal, 4101 Rue Sherbrooke E, Montréal, QC, H1X 2B2, Canada
| | - Daniel J Schoen
- Biology Department, McGill University, 205 Av. du Docteur-Penfield, Montréal, QC, H3A 1B1, Canada
| | - Simon Joly
- Département de Sciences Biologiques, Institut de Recherche en Biologie Végétale, Université de Montréal, 4101 Rue Sherbrooke E, Montréal, QC, H1X 2B2, Canada
- Jardin Botanique de Montréal, 4101 Rue Sherbrooke E, Montréal, QC, H1X 2B2, Canada
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3
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Cox Jr KL, Gurazada SGR, Duncan KE, Czymmek KJ, Topp CN, Meyers BC. Organizing your space: The potential for integrating spatial transcriptomics and 3D imaging data in plants. PLANT PHYSIOLOGY 2022; 188:703-712. [PMID: 34726737 PMCID: PMC8825300 DOI: 10.1093/plphys/kiab508] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 10/04/2021] [Indexed: 05/31/2023]
Abstract
Plant cells communicate information for the regulation of development and responses to external stresses. A key form of this communication is transcriptional regulation, accomplished via complex gene networks operating both locally and systemically. To fully understand how genes are regulated across plant tissues and organs, high resolution, multi-dimensional spatial transcriptional data must be acquired and placed within a cellular and organismal context. Spatial transcriptomics (ST) typically provides a two-dimensional spatial analysis of gene expression of tissue sections that can be stacked to render three-dimensional data. For example, X-ray and light-sheet microscopy provide sub-micron scale volumetric imaging of cellular morphology of tissues, organs, or potentially entire organisms. Linking these technologies could substantially advance transcriptomics in plant biology and other fields. Here, we review advances in ST and 3D microscopy approaches and describe how these technologies could be combined to provide high resolution, spatially organized plant tissue transcript mapping.
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Affiliation(s)
- Kevin L Cox Jr
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132, USA
- Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA
| | - Sai Guna Ranjan Gurazada
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132, USA
- Delaware Biotechnology Institute, University of Delaware, Newark, Delaware 19711, USA
| | - Keith E Duncan
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132, USA
| | - Kirk J Czymmek
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132, USA
- Advanced Bioimaging Laboratory, Donald Danforth Plant Science Center, St Louis, Missouri 63132, USA
| | | | - Blake C Meyers
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132, USA
- Division of Plant Sciences and Technology, University of Missouri–Columbia, Columbia, MO 65211, USA
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4
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Duncan KE, Czymmek KJ, Jiang N, Thies AC, Topp CN. X-ray microscopy enables multiscale high-resolution 3D imaging of plant cells, tissues, and organs. PLANT PHYSIOLOGY 2022; 188:831-845. [PMID: 34618094 PMCID: PMC8825331 DOI: 10.1093/plphys/kiab405] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 07/29/2021] [Indexed: 05/12/2023]
Abstract
Capturing complete internal anatomies of plant organs and tissues within their relevant morphological context remains a key challenge in plant science. While plant growth and development are inherently multiscale, conventional light, fluorescence, and electron microscopy platforms are typically limited to imaging of plant microstructure from small flat samples that lack a direct spatial context to, and represent only a small portion of, the relevant plant macrostructures. We demonstrate technical advances with a lab-based X-ray microscope (XRM) that bridge the imaging gap by providing multiscale high-resolution three-dimensional (3D) volumes of intact plant samples from the cell to the whole plant level. Serial imaging of a single sample is shown to provide sub-micron 3D volumes co-registered with lower magnification scans for explicit contextual reference. High-quality 3D volume data from our enhanced methods facilitate sophisticated and effective computational segmentation. Advances in sample preparation make multimodal correlative imaging workflows possible, where a single resin-embedded plant sample is scanned via XRM to generate a 3D cell-level map, and then used to identify and zoom in on sub-cellular regions of interest for high-resolution scanning electron microscopy. In total, we present the methodologies for use of XRM in the multiscale and multimodal analysis of 3D plant features using numerous economically and scientifically important plant systems.
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Affiliation(s)
- Keith E Duncan
- Donald Danforth Plant Science Center, St Louis, Missouri 63132, USA
| | - Kirk J Czymmek
- Donald Danforth Plant Science Center, St Louis, Missouri 63132, USA
| | - Ni Jiang
- Donald Danforth Plant Science Center, St Louis, Missouri 63132, USA
| | | | - Christopher N Topp
- Donald Danforth Plant Science Center, St Louis, Missouri 63132, USA
- Author for communication:
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Chen K, Zhang W, La T, Bastians PA, Guo T, Cao C. Microstructure investigation of plant architecture with X-ray microscopy. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2021; 311:110986. [PMID: 34482923 DOI: 10.1016/j.plantsci.2021.110986] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 06/22/2021] [Accepted: 06/25/2021] [Indexed: 06/13/2023]
Abstract
In recent years, the plant morphology has been well studied by multiple approaches at cellular and subcellular levels. Two-dimensional (2D) microscopy techniques offer imaging of plant structures on a wide range of magnifications for researchers. However, subcellular imaging is still challenging in plant tissues like roots and seeds. Here we use a three-dimensional (3D) imaging technology based on the X-ray microscope (XRM) and analyze several plant tissues from different plant species. The XRM provides new insights into plant structures using non-destructive imaging at high-resolution and high contrast. We also utilized a workflow aiming to acquire accurate and high-quality images in the context of the whole specimen. Multiple plant samples including rice, tobacco, Arabidopsis and maize were used to display the differences of phenotypes. Our work indicates that the XRM is a powerful tool to investigate plant microstructure in high-resolution scale. Our work also provides evidence that evaluate and quantify tissue specific differences for a range of plant species. We also characterize novel plant tissue phenotypes by the XRM, such as seeds in Arabidopsis, and utilize them for novel observation measurement. Our work represents an evaluated spatial and temporal resolution solution on seed observation and screening.
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Affiliation(s)
- Ke Chen
- Rice Research Institute, Guangdong Academy of Agricultural Sciences/Guangdong Provincial Key Laboratory of New Technology in Rice Breeding, Guangzhou, 510640, Guangdong, China; King Abdullah University of Science and Technology (KAUST), Biological and Environmental Science and Engineering (BESE), 23955-6900, Thuwal, Saudi Arabia
| | - Wenting Zhang
- Crops Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China
| | - Ting La
- School of Biomedical Sciences and Pharmacy, The University of Newcastle, NSW, 2308, Australia
| | | | - Tao Guo
- National Key Laboratory of Plant Molecular Genetics, CAS Centre for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology & Ecology, Chinese Academic of Sciences, Shanghai, 200032, China.
| | - Chunjie Cao
- Carl Zeiss (Shanghai) Co., Ltd, Beijing, 100191, China.
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Abstract
Recent developments within micro-computed tomography (μCT) imaging have combined to extend our capacity to image tissue in three (3D) and four (4D) dimensions at micron and sub-micron spatial resolutions, opening the way for virtual histology, live cell imaging, subcellular imaging and correlative microscopy. Pivotal to this has been the development of methods to extend the contrast achievable for soft tissue. Herein, we review the new capabilities within the field of life sciences imaging, and consider how future developments in this field could further benefit the life sciences community.
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Affiliation(s)
- Shelley D Rawson
- The Henry Royce Institute and School of Materials, The University of Manchester, Manchester, M13 9PL, UK
| | - Jekaterina Maksimcuka
- The Henry Royce Institute and School of Materials, The University of Manchester, Manchester, M13 9PL, UK
| | - Philip J Withers
- The Henry Royce Institute and School of Materials, The University of Manchester, Manchester, M13 9PL, UK
| | - Sarah H Cartmell
- The Henry Royce Institute and School of Materials, The University of Manchester, Manchester, M13 9PL, UK.
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Koç MM, Aslan N, Kao AP, Barber AH. Evaluation of X-ray tomography contrast agents: A review of production, protocols, and biological applications. Microsc Res Tech 2019; 82:812-848. [PMID: 30786098 DOI: 10.1002/jemt.23225] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 01/02/2019] [Accepted: 01/12/2019] [Indexed: 12/25/2022]
Abstract
X-ray computed tomography is a strong tool that finds many applications both in medical applications and in the investigation of biological and nonbiological samples. In the clinics, X-ray tomography is widely used for diagnostic purposes whose three-dimensional imaging in high resolution helps physicians to obtain detailed image of investigated regions. Researchers in biological sciences and engineering use X-ray tomography because it is a nondestructive method to assess the structure of their samples. In both medical and biological applications, visualization of soft tissues and structures requires special treatment, in which special contrast agents are used. In this detailed report, molecule-based and nanoparticle-based contrast agents used in biological applications to enhance the image quality were compiled and reported. Special contrast agent applications and protocols to enhance the contrast for the biological applications and works to develop nanoparticle contrast agents to enhance the contrast for targeted drug delivery and general imaging applications were also assessed and listed.
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Affiliation(s)
- Mümin Mehmet Koç
- School of Engineering, University of Portsmouth, Portsmouth, United Kingdom.,Department of Physics, Kirklareli University, Kirklareli, Turkey
| | - Naim Aslan
- Department of Metallurgical and Materials Engineering, Munzur University, Tunceli, Turkey
| | - Alexander P Kao
- School of Engineering, University of Portsmouth, Portsmouth, United Kingdom
| | - Asa H Barber
- School of Engineering, London South Bank University, London, United Kingdom
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8
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Endress PK. Development and evolution of extreme synorganization in angiosperm flowers and diversity: a comparison of Apocynaceae and Orchidaceae. ANNALS OF BOTANY 2016; 117:749-67. [PMID: 26292994 PMCID: PMC4845794 DOI: 10.1093/aob/mcv119] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Accepted: 06/22/2015] [Indexed: 05/04/2023]
Abstract
BACKGROUND AND AIMS Apocynaceae and Orchidaceae are two angiosperm families with extreme flower synorganization. They are unrelated, the former in eudicots, the latter in monocots, but they converge in the formation of pollinia and pollinaria, which do not occur in any other angiosperm family, and for which extreme synorganization of floral organs is a precondition. In each family extensive studies on flower development and evolution have been performed; however, newer comparative studies focusing on flower synorganization and involving both families together are lacking. SCOPE For this study an extensive search through the morphological literature has been conducted. Based on this and my own studies on flowers in various Apocynaceae and Orchidaceae and complex flowers in other angiosperms with scanning electron microscopy and with microtome section series, a review on convergent floral traits in flower development and architecture in the two families is presented. KEY FINDINGS There is a tendency of protracted development of synorganized parts in Apocynaceae and Orchidaceae (development of synorganization of two or more organs begins earlier the more accentuated it is at anthesis). Synorganization (or complexity) also paves the way for novel structures. One of the most conspicuous such novel structures in Apocynaceae is the corona, which is not the product of synorganization of existing organs; however, it is probably enhanced by synorganization of other, existing, floral parts. In contrast to synorganized parts, the corona appears developmentally late. CONCLUSIONS Synorganization of floral organs may lead to a large number of convergences in clades that are only very distantly related. The convergences that have been highlighted in this comparative study should be developmentally investigated directly in parallel in future studies.
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Affiliation(s)
- Peter K Endress
- Institute of Systematic Botany, University of Zurich, Zollikerstrasse 107, 8008 Zurich, Switzerland
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Gamisch A, Fischer GA, Comes HP. Frequent but asymmetric niche shifts in Bulbophyllum orchids support environmental and climatic instability in Madagascar over Quaternary time scales. BMC Evol Biol 2016; 16:14. [PMID: 26781289 PMCID: PMC4717530 DOI: 10.1186/s12862-016-0586-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 01/12/2016] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Species or clades may retain or shift their environmental niche space over evolutionary time. Understanding these processes offers insights into the environmental processes fuelling lineage diversification and might also provide information on past range dynamics of ecosystems. However, little is known about the relative contributions of niche conservatism versus niche divergence to species diversification in the tropics. Here, we examined broad-scale patterns of niche evolution within a Pliocene-Pleistocene clade of epiphytic Bulbophyllum orchids (30 spp.) whose collective distribution covers the northwest and eastern forest ecosystems of Madagascar. RESULTS Using species occurrence data, ecological niche models, and multivariate analyses of contributing variables, we identified a three-state niche distribution character for the entire clade, coinciding with three major forest biomes viz. phytogeographical provinces in Madagascar: A, Northwest 'Sambirano'; B, 'Eastern Lowlands'; and C, 'Central Highlands'. A time-calibrated phylogeny and Bayesian models of niche evolution were then used to detect general trends in the direction of niche change over the clade's history (≤5.3 Ma). We found highest transitions rates between lowlands (A and B) and (mostly from B) into the highland (C), with extremely low rates out of the latter. Lowland-to-highland transitions occurred frequently during the Quaternary, suggesting that climate-induced vegetational shifts promoted niche transitions and ecological speciation at this time. CONCLUSIONS Our results reveal that niche transitions occurred frequently and asymmetrically within this Madagascan orchid clade, and in particular over Quaternary time scales. Intrinsic features germane to Bulbophyllum (e.g., high dispersal ability, drought tolerance, multiple photosynthetic pathways) as well as extrinsic factors (ecological, historical) likely interacted to generate the niche transition patterns observed. In sum, our results support the emerging idea of dramatic environmental and climatic fluctuations in Madagascar during the recent geological past, which overturns the long-held paradigm of long-term stability in tropical forest settings. The generality of the patterns and timings reported here awaits the availability of additional comparative studies in other Madagascan endemics.
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Affiliation(s)
- Alexander Gamisch
- Department of Ecology and Evolution, University of Salzburg, A-5020, Salzburg, Austria.
| | | | - Hans Peter Comes
- Department of Ecology and Evolution, University of Salzburg, A-5020, Salzburg, Austria.
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Gamisch A, Fischer GA, Comes HP. Multiple independent origins of auto-pollination in tropical orchids (Bulbophyllum) in light of the hypothesis of selfing as an evolutionary dead end. BMC Evol Biol 2015; 15:192. [PMID: 26376901 PMCID: PMC4574068 DOI: 10.1186/s12862-015-0471-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 08/28/2015] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND The transition from outcrossing to selfing has long been portrayed as an 'evolutionary dead end' because, first, reversals are unlikely and, second, selfing lineages suffer from higher rates of extinction owing to a reduced potential for adaptation and the accumulation of deleterious mutations. We tested these two predictions in a clade of Madagascan Bulbophyllum orchids (30 spp.), including eight species where auto-pollinating morphs (i.e., selfers, without a 'rostellum') co-exist with their pollinator-dependent conspecifics (i.e., outcrossers, possessing a rostellum). Specifically, we addressed this issue on the basis of a time-calibrated phylogeny by means of ancestral character reconstructions and within the state-dependent evolution framework of BiSSE (Binary State Speciation and Extinction), which allowed jointly estimating rates of transition, speciation, and extinction between outcrossing and selfing. RESULTS The eight species capable of selfing occurred in scattered positions across the phylogeny, with two likely originating in the Pliocene (ca. 4.4-3.1 Ma), one in the Early Pleistocene (ca. 2.4 Ma), and five since the mid-Pleistocene (ca. ≤ 1.3 Ma). We infer that this scattered phylogenetic distribution of selfing is best described by models including up to eight independent outcrossing-to-selfing transitions and very low rates of speciation (and either moderate or zero rates of extinction) associated with selfing. CONCLUSIONS The frequent and irreversible outcrossing-to-selfing transitions in Madagascan Bulbophyllum are clearly congruent with the first prediction of the dead end hypothesis. The inability of our study to conclusively reject or support the likewise predicted higher extinction rate in selfing lineages might be explained by a combination of methodological limitations (low statistical power of our BiSSE approach to reliably estimate extinction in small-sized trees) and evolutionary processes (insufficient time elapsed for selfers to go extinct). We suggest that, in these tropical orchids, a simple genetic basis of selfing (via loss of the 'rostellum') is needed to explain the strikingly recurrent transitions to selfing, perhaps reflecting rapid response to parallel and novel selective environments over Late Quaternary (≤ 1.3 Ma) time scales.
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Affiliation(s)
- Alexander Gamisch
- Department of Ecology and Evolution, University of Salzburg, A-5020, Salzburg, Austria.
| | | | - Hans Peter Comes
- Department of Ecology and Evolution, University of Salzburg, A-5020, Salzburg, Austria.
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Gamisch A, Fischer GA, Comes HP. Recurrent polymorphic mating type variation in Madagascan Bulbophyllum species (Orchidaceae) exemplifies a high incidence of auto-pollination in tropical orchids. BOTANICAL JOURNAL OF THE LINNEAN SOCIETY. LINNEAN SOCIETY OF LONDON 2014; 175:242-258. [PMID: 25821245 PMCID: PMC4373168 DOI: 10.1111/boj.12168] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 12/11/2013] [Accepted: 03/24/2014] [Indexed: 05/13/2023]
Abstract
The transition from outcrossing to self-fertilization is one of the most common evolutionary changes in angiosperms. The orchid family exemplifies this evolutionary trend but, because of a general lack of large-scale surveys on auto-pollination in orchid taxa, the incidence and modes of auto-pollination among (sub)tropical orchids remain poorly known. In the present study, we assessed the frequency and mode of auto-pollination within and among species of a largely monophyletic group of Madagascan Bulbophyllum. The capacity for autonomous fruit set was investigated by bagging experiments in the greenhouse and the field, complemented with detailed floral micromorphological studies of the gynostemium. Our survey comprises 393 accessions, representing at least 78 species, and thus approximately 37% of the species diversity of the genus in the Madagascan region. Our studies revealed that mating type is directly related to gynostemium structure, most often involving the presence or absence of a physical barrier termed 'rostellum'. As a novel and unexpected finding, we identified eight species of a single lineage of Madagascan Bulbophyllum (termed 'clade C'), in which auto-pollinating morphs (selfers), either lacking a rostellum or (rarely) possessing a stigmatic rostellum, co-exist with their pollinator-dependent conspecifics (outcrossers). We hypothesize that auto-pollination via rostellum abortion has a simple genetic basis, and probably evolved rapidly and recurrently by subtle changes in the timing of rostellum development (heterochrony). Thus, species of clade C may have an intrinsic genetic and developmental lability toward auto-pollination, allowing rapid evolutionary response under environmental, perhaps human-disturbed conditions favouring reproductive assurance. Overall, these findings should stimulate further research on the incidence, evolution, and maintenance of mating type variation in tropical orchids, as well as how they adapt(ed) to changing environmental conditions.
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Affiliation(s)
- Alexander Gamisch
- Department of Organismic Biology, University of SalzburgA-5020, Salzburg, Austria
- *Corresponding author. E-mail:
| | - Gunter A Fischer
- Kadoorie Farm and Botanic Garden CorporationLam Kam Road, Tai Po, N.T., Hong Kong SAR
| | - Hans Peter Comes
- Department of Organismic Biology, University of SalzburgA-5020, Salzburg, Austria
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Bellaire A, Ischebeck T, Staedler Y, Weinhaeuser I, Mair A, Parameswaran S, Ito T, Schönenberger J, Weckwerth W. Metabolism and development - integration of micro computed tomography data and metabolite profiling reveals metabolic reprogramming from floral initiation to silique development. THE NEW PHYTOLOGIST 2014; 202:322-335. [PMID: 24350948 PMCID: PMC4283998 DOI: 10.1111/nph.12631] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 11/03/2013] [Indexed: 05/22/2023]
Abstract
The interrelationship of morphogenesis and metabolism is a poorly studied phenomenon. The main paradigm is that development is controlled by gene expression. The aim of the present study was to correlate metabolism to early and late stages of flower and fruit development in order to provide the basis for the identification of metabolic adjustment and limitations. A highly detailed picture of morphogenesis is achieved using nondestructive micro computed tomography. This technique was used to quantify morphometric parameters of early and late flower development in an Arabidopsis thaliana mutant with synchronized flower initiation. The synchronized flower phenotype made it possible to sample enough early floral tissue otherwise not accessible for metabolomic analysis. The integration of metabolomic and morphometric data enabled the correlation of metabolic signatures with the process of flower morphogenesis. These signatures changed significantly during development, indicating a pronounced metabolic reprogramming in the tissue. Distinct sets of metabolites involved in these processes were identified and were linked to the findings of previous gene expression studies of flower development. High correlations with basic leucine zipper (bZIP) transcription factors and nitrogen metabolism genes involved in the control of metabolic carbon : nitrogen partitioning were revealed. Based on these observations a model for metabolic adjustment during flower development is proposed.
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Affiliation(s)
- Anke Bellaire
- Department of Structural and Functional Botany, Faculty of Life Sciences, University of ViennaRennweg 14, Vienna, Austria
- * These authors contributed equally to this work
| | - Till Ischebeck
- Department of Ecogenomics and Systems Biology, Faculty of Life Sciences, University of ViennaAlthanstrasse 14, Vienna, Austria
- * These authors contributed equally to this work
| | - Yannick Staedler
- Department of Structural and Functional Botany, Faculty of Life Sciences, University of ViennaRennweg 14, Vienna, Austria
- * These authors contributed equally to this work
| | - Isabell Weinhaeuser
- Department of Ecogenomics and Systems Biology, Faculty of Life Sciences, University of ViennaAlthanstrasse 14, Vienna, Austria
| | - Andrea Mair
- Department of Ecogenomics and Systems Biology, Faculty of Life Sciences, University of ViennaAlthanstrasse 14, Vienna, Austria
| | - Sriram Parameswaran
- Temasek Life Sciences Laboratory, National University of SingaporeSingapore, Singapore
| | - Toshiro Ito
- Temasek Life Sciences Laboratory, National University of SingaporeSingapore, Singapore
| | - Jürg Schönenberger
- Department of Structural and Functional Botany, Faculty of Life Sciences, University of ViennaRennweg 14, Vienna, Austria
| | - Wolfram Weckwerth
- Department of Ecogenomics and Systems Biology, Faculty of Life Sciences, University of ViennaAlthanstrasse 14, Vienna, Austria
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13
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Staedler YM, Masson D, Schönenberger J. Plant tissues in 3D via X-ray tomography: simple contrasting methods allow high resolution imaging. PLoS One 2013; 8:e75295. [PMID: 24086499 PMCID: PMC3785515 DOI: 10.1371/journal.pone.0075295] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2013] [Accepted: 08/14/2013] [Indexed: 11/19/2022] Open
Abstract
Computed tomography remains strongly underused in plant sciences despite its high potential in delivering detailed 3D phenotypical information because of the low X-ray absorption of most plant tissues. Existing protocols to study soft tissues display poor performance, especially when compared to those used on animals. More efficient protocols to study plant material are therefore needed. Flowers of Arabidopsis thaliana and Marcgravia caudata were immersed in a selection of contrasting agents used to treat samples for transmission electron microscopy. Grayscale values for floral tissues and background were measured as a function of time. Contrast was quantified via a contrast index. The thick buds of Marcgravia were scanned to determine which contrasting agents best penetrate thick tissues. The highest contrast increase with cytoplasm-rich tissues was obtained with phosphotungstate, whereas osmium tetroxide and bismuth tatrate displayed the highest contrast increase with vacuolated tissues. Phosphotungstate also displayed the best sample penetration. Furthermore, infiltration with phosphotungstate allowed imaging of all plants parts at a high resolution of 3 µm, which approaches the maximum resolution of our equipment: 1.5 µm. The high affinity of phosphotungstate for vasculature, cytoplasm-rich tissue, and pollen causes these tissues to absorb more X-rays than the surrounding tissues, which, in turn, makes these tissues appear brighter on the scan data. Tissues with different brightness can then be virtually dissected from each other by selecting the bracket of grayscale to be visualized. Promising directions for the future include in silico phenotyping and developmental studies of plant inner parts (e.g., ovules, vasculature, pollen, and cell nuclei) via virtual dissection as well as correlations of quantitative phenotypes with omics datasets. Therefore, this work represents a crucial improvement of previous methods, allowing new directions of research to be undertaken in areas ranging from morphology to systems biology.
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Affiliation(s)
- Yannick M. Staedler
- Department of Structural and Functional Botany, University of Vienna, Vienna, Austria
- * E-mail:
| | - David Masson
- Federal Office of Meteorology and Climatology, MeteoSwiss, Zurich, Switzerland
| | - Jürg Schönenberger
- Department of Structural and Functional Botany, University of Vienna, Vienna, Austria
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