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Romanov MS, Bobrov AVFC, Iovlev PS, Roslov MS, Zdravchev NS, Sorokin AN, Romanova ES, Kandidov MV. Fruit and seed structure in the ANA-grade angiosperms: Ancestral traits and specializations. Am J Bot 2024; 111:e16264. [PMID: 38031509 DOI: 10.1002/ajb2.16264] [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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 10/27/2023] [Accepted: 10/27/2023] [Indexed: 12/01/2023]
Abstract
PREMISE The representatives of the ANA-grade angiosperms demonstrate a diverse pattern of morphological characters, but their apocarpous gynoecium (except in Nymphaeaceae), composed of at least partly ascidiate carpels, the four-nucleate and four-celled female gametophyte, and the diploid endosperm (except in Amborella) are inferred to be plesiomorphies. Since the structure of fruits in Austrobaileyales is under-investigated, this research aims to fill this gap in these data, describing the carpological characters of ANA-grade taxa, and potentially illuminating the ancestral fruit and seed types of angiosperms. METHODS The pericarp and seed coat anatomy was studied with light microscopy. The character optimization was carried out using WinClada software. RESULTS The fruits of Austrobaileya, Trimenia, Kadsura, and Schisandra are determined to be apocarpous berries of the Schisandra type, with a parenchymatous pericarp and mesotestal (Austrobaileya) or exomesotestal seeds (other genera). Most inferred scenarios of fruit evolution indicate that the apocarpous berry is either the most probable plesiomorphic fruit type of all angiosperms, or that of all angiosperms except Amborellaceae. This inference suggests the early origin of the berry in fruit evolution. The plesiomorphic seed type of angiosperms according to reconstructed scenarios of seed type evolution was either a seed lacking a sclerenchymatous layer or an exotestal seed. CONCLUSIONS The current research indicates that an apocarpous berry, and not a follicle, is a probable plesiomorphic character of the ANA-grade taxa and of angiosperms as a whole.
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Affiliation(s)
- Mikhail S Romanov
- Laboratory of Tropical Plants, Tsitsin Main Botanical Garden of Russian Academy of Sciences, Botanicheskaya st., 4, Moscow, 127276, Russia
| | - Alexey V F Ch Bobrov
- Department of Biogeography, Geographical Faculty, M. V. Lomonosov Moscow State University, Moscow, 119992, Russia
| | - Peter S Iovlev
- Laboratory of Tropical Plants, Tsitsin Main Botanical Garden of Russian Academy of Sciences, Botanicheskaya st., 4, Moscow, 127276, Russia
| | - Maxim S Roslov
- Department of Biogeography, Geographical Faculty, M. V. Lomonosov Moscow State University, Moscow, 119992, Russia
| | - Nikita S Zdravchev
- Laboratory of Tropical Plants, Tsitsin Main Botanical Garden of Russian Academy of Sciences, Botanicheskaya st., 4, Moscow, 127276, Russia
| | - Alexey N Sorokin
- Laboratory of Tropical Plants, Tsitsin Main Botanical Garden of Russian Academy of Sciences, Botanicheskaya st., 4, Moscow, 127276, Russia
| | - Ekaterina S Romanova
- Botanical Garden, Biological Faculty, M. V. Lomonosov Moscow State University, Moscow, 119992, Russia
| | - Maxim V Kandidov
- Department of Biogeography, Geographical Faculty, M. V. Lomonosov Moscow State University, Moscow, 119992, Russia
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Leslie AB, Mander L. Quantifying the complexity of plant reproductive structures reveals a history of morphological and functional integration. Proc Biol Sci 2023; 290:20231810. [PMID: 37909082 PMCID: PMC10618862 DOI: 10.1098/rspb.2023.1810] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 10/09/2023] [Indexed: 11/02/2023] Open
Abstract
Vascular plant reproductive structures have undoubtedly become more complex through time, evolving highly differentiated parts that interact in specialized ways. But quantifying these patterns at broad scales is challenging because lineages produce disparate reproductive structures that are often difficult to compare and homologize. We develop a novel approach for analysing interactions within reproductive structures using networks, treating component parts as nodes and a suite of physical and functional interactions among parts as edges. We apply this approach to the plant fossil record, showing that interactions have generally increased through time and that the concentration of these interactions has shifted towards differentiated surrounding organs, resulting in more compact, functionally integrated structures. These processes are widespread across plant lineages, but their extent and timing vary with reproductive biology; in particular, seed-producing structures show them more strongly than spore or pollen-producing structures. Our results demonstrate that major reproductive innovations like the origin of seeds and angiospermy were associated with increased integration through greater interactions among parts. But they also reveal that for certain groups, particularly Mesozoic gymnosperms, millions of years elapsed between the origin of reproductive innovations and increased interactions among parts within their reproductive structures.
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Affiliation(s)
- Andrew B. Leslie
- Department of Geological Sciences, Stanford University, 450 Jane Stanford Way, Building 320, Room 118, Stanford, CA 94305, USA
| | - Luke Mander
- School of Environment, Earth and Ecosystem Sciences, Open University, Walton Hall, Milton Keynes MK7 6AA, UK
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Baczyński J, Claßen-Bockhoff R. Pseudanthia in angiosperms: a review. Ann Bot 2023; 132:179-202. [PMID: 37478306 PMCID: PMC10583202 DOI: 10.1093/aob/mcad103] [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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 07/19/2023] [Indexed: 07/23/2023]
Abstract
BACKGROUND Pseudanthia or 'false flowers' are multiflowered units that resemble solitary flowers in form and function. Over the last century the term 'pseudanthium' has been applied to a wide array of morphologically divergent blossoms, ranging from those with easily noticeable florets to derived, reduced units in which individual flowers become almost indistinguishable. Although initially admired mostly by botanists, the diversity and widespread distribution of pseudanthia across angiosperms has already made them a fascinating topic for evolutionary and developmental comparative studies. SCOPE This review synthesizes historical and current concepts on the biology of pseudanthia. Our first aim is to establish a clear, operational definition of pseudanthium and disentangle common terminological misconceptions surrounding that term. Our second aim is to summarize knowledge of the morphological and developmental diversity of pseudanthia and embed it within a modern phylogenetic framework. Lastly, we want to provide a comprehensive overview on the evolution and ecological importance of pseudanthia and outline perspectives for future studies. CONCLUSIONS The understanding of pseudanthia has changed multiple times and reflects three different interpretations of their 'flower-like' qualities: developmental (similarity in structure), figural (similarity in form and function) and phylogenetic (homology between angiosperm flowers and monoecious reproductive shoots in gymnosperms). Here, we propose to narrow the term pseudanthium to multiflowered blossoms resembling zoophilous flowers in form, i.e. in being structurally subdivided in a showy periphery and a reproductive centre. According to this definition, pseudanthia sensu stricto evolved independently in at least 41 angiosperm families. The recurrent acquisition of pseudanthia sensu stricto in all major lineages of flowering plants indicates repeated interactions between developmental constraints (smallness of flowers, meristematic conditions) and selective pressures, such as demands of pollinators and/or environmental conditions.
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Affiliation(s)
- Jakub Baczyński
- Institute of Evolutionary Biology, Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, Warsaw, Poland
- Department of Plant Biology, Miller Plant Sciences, University of Georgia, Athens, Georgia, USA
| | - Regine Claßen-Bockhoff
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg-University, Mainz, Germany
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Herting J, Schönenberger J, Sauquet H. Profile of a flower: How rates of morphological evolution drive floral diversification in Ericales and angiosperms. Am J Bot 2023; 110:e16213. [PMID: 37459475 DOI: 10.1002/ajb2.16213] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [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: 11/28/2022] [Revised: 05/26/2023] [Accepted: 05/26/2023] [Indexed: 08/12/2023]
Abstract
PREMISE Recent studies of floral disparity in the asterid order Ericales have shown that flowers vary strongly among families and that disparity is unequally distributed between the three flower modules (perianth, androecium, gynoecium). However, it remains unknown whether these patterns are driven by heterogeneous rates of morphological evolution or other factors. METHODS Here, we compiled a data set of 33 floral characters scored for 414 species of Ericales sampled from 346 genera and all 22 families. We conducted ancestral state reconstructions using an equal-rates Markov model for each character. We estimated rates of morphological evolution for Ericales and for a separate angiosperm-wide data set of 19 characters and 792 species, creating "rate profiles" for Ericales, angiosperms, and major angiosperm subclades. We compared morphological rates among flower modules within each data set separately and between data sets, and we compared rates among angiosperm subclades using the angiosperm data set. RESULTS The androecium exhibits the highest evolutionary rates across most characters, whereas most perianth and gynoecium characters evolve more slowly in both Ericales and angiosperms. Both high and low rates of morphological evolution can result in high floral disparity in Ericales. Analyses of an angiosperm-wide floral data set reveal that this pattern appears to be conserved across most major angiosperm clades. CONCLUSIONS Elevated rates of morphological evolution in the androecium of Ericales may explain the higher disparity reported for this floral module. Comparing rates of morphological evolution through rate profiles proves to be a powerful tool in understanding floral evolution.
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Affiliation(s)
- Julian Herting
- National Herbarium of New South Wales, Botanic Gardens Sydney, Locked Bag 6002, Mount Annan, NSW 2567, Australia
| | - Jürg Schönenberger
- Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, Vienna, A-1030, Austria
| | - Hervé Sauquet
- National Herbarium of New South Wales, Botanic Gardens Sydney, Locked Bag 6002, Mount Annan, NSW 2567, Australia
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales Sydney, NSW 2052, Australia
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Jiang GF, Li SY, Dinnage R, Cao KF, Simonin KA, Roddy AB. Diverse mangroves deviate from other angiosperms in their genome size, leaf cell size and cell packing density relationships. Ann Bot 2023; 131:347-360. [PMID: 36516425 PMCID: PMC9992938 DOI: 10.1093/aob/mcac151] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [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: 08/11/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
BACKGROUND AND AIMS While genome size limits the minimum sizes and maximum numbers of cells that can be packed into a given leaf volume, mature cell sizes can be substantially larger than their meristematic precursors and vary in response to abiotic conditions. Mangroves are iconic examples of how abiotic conditions can influence the evolution of plant phenotypes. METHODS Here, we examined the coordination between genome size, leaf cell sizes, cell packing densities and leaf size in 13 mangrove species across four sites in China. Four of these species occurred at more than one site, allowing us to test the effect of climate on leaf anatomy. RESULTS We found that genome sizes of mangroves were very small compared to other angiosperms, but, like other angiosperms, mangrove cells were always larger than the minimum size defined by genome size. Increasing mean annual temperature of a growth site led to higher packing densities of veins (Dv) and stomata (Ds) and smaller epidermal cells but had no effect on stomatal size. In contrast to other angiosperms, mangroves exhibited (1) a negative relationship between guard cell size and genome size; (2) epidermal cells that were smaller than stomata; and (3) coordination between Dv and Ds that was not mediated by epidermal cell size. Furthermore, mangrove epidermal cell sizes and packing densities covaried with leaf size. CONCLUSIONS While mangroves exhibited coordination between veins and stomata and attained a maximum theoretical stomatal conductance similar to that of other angiosperms, the tissue-level tradeoffs underlying these similar relationships across species and environments were markedly different, perhaps indicative of the unique structural and physiological adaptations of mangroves to their stressful environments.
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Affiliation(s)
| | - Su-Yuan Li
- Guangxi Key Laboratory of Forest Ecology and Conservation, and State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Forestry, Guangxi University, Daxuedonglu 100, Nanning, Guangxi 530004, PR China
| | - Russell Dinnage
- Institute of Environment, Department of Biological Sciences, Florida International University, Miami, FL 33199USA
| | - Kun-Fang Cao
- Guangxi Key Laboratory of Forest Ecology and Conservation, and State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Forestry, Guangxi University, Daxuedonglu 100, Nanning, Guangxi 530004, PR China
| | - Kevin A Simonin
- Department of Biology, San Francisco State University, San Francisco, CA 94132USA
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Sokoloff DD, Fomichev CI, Rudall PJ, Macfarlane TD, Remizowa MV. Evolutionary history of the grass gynoecium. J Exp Bot 2022; 73:4637-4661. [PMID: 35512454 DOI: 10.1093/jxb/erac182] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [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: 11/06/2021] [Accepted: 05/03/2022] [Indexed: 06/14/2023]
Abstract
The grass family (Poaceae) includes cereal crops that provide a key food source for the human population. The food industry uses the starch deposited in the cereal grain, which develops directly from the gynoecium. Morphological interpretation of the grass gynoecium remains controversial. We re-examine earlier hypotheses and studies of morphology and development in the context of more recent analyses of grass phylogenetics and developmental genetics. Taken in isolation, data on gynoecium development in bistigmatic grasses do not contradict its interpretation as a solitary ascidiate carpel. Nevertheless, in the context of other data, this interpretation is untenable. Broad comparative analysis in a modern phylogenetic context clearly demonstrates that the grass gynoecium is pseudomonomerous. A bistigmatic grass gynoecium has two sterile carpels, each producing a stigma, and a fertile carpel that lacks a stigma. To date, studies of grass developmental genetics and developmental morphology have failed to fully demonstrate the composite nature of the grass gynoecium be-cause its complex evolutionary history is hidden by extreme organ integration. It is problematic to interpret the gynoecium of grasses in terms of normal angiosperm gynoecium typology. Even the concept of a carpel becomes misleading in grasses; instead, we recommend the term pistil for descriptive purposes.
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Affiliation(s)
- Dmitry D Sokoloff
- Faculty of Biology, M.V. Lomonosov Moscow State University, 1, 12, Leninskie Gory, 119234 Moscow, Russia
| | - Constantin I Fomichev
- Faculty of Biology, M.V. Lomonosov Moscow State University, 1, 12, Leninskie Gory, 119234 Moscow, Russia
| | - Paula J Rudall
- Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, UK
| | - Terry D Macfarlane
- Western Australian Herbarium, Biodiversity and Conservation Science, Department of Biodiversity, Conservation and Attractions, Locked Bag 104, Bentley Delivery Centre WA 6983, Australia
| | - Margarita V Remizowa
- Faculty of Biology, M.V. Lomonosov Moscow State University, 1, 12, Leninskie Gory, 119234 Moscow, Russia
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7
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Spagnuolo EJ, Wilf P, Serre T. Decoding family-level features for modern and fossil leaves from computer-vision heat maps. Am J Bot 2022; 109:768-788. [PMID: 35319778 DOI: 10.1002/ajb2.1842] [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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 03/07/2022] [Accepted: 03/08/2022] [Indexed: 06/14/2023]
Abstract
PREMISE Angiosperm leaves present a classic identification problem due to their morphological complexity. Computer-vision algorithms can identify diagnostic regions in images, and heat map outputs illustrate those regions for identification, providing novel insights through visual feedback. We investigate the potential of analyzing leaf heat maps to reveal novel, human-friendly botanical information with applications for extant- and fossil-leaf identification. METHODS We developed a manual scoring system for hotspot locations on published computer-vision heat maps of cleared leaves that showed diagnostic regions for family identification. Heat maps of 3114 cleared leaves of 930 genera in 14 angiosperm families were analyzed. The top-5 and top-1 hotspot regions of highest diagnostic value were scored for 21 leaf locations. The resulting data were viewed using box plots and analyzed using cluster and principal component analyses. We manually identified similar features in fossil leaves to informally demonstrate potential fossil applications. RESULTS The method successfully mapped machine strategy using standard botanical language, and distinctive patterns emerged for each family. Hotspots were concentrated on secondary veins (Salicaceae, Myrtaceae, Anacardiaceae), tooth apices (Betulaceae, Rosaceae), and on the little-studied margins of untoothed leaves (Rubiaceae, Annonaceae, Ericaceae). Similar features drove the results from multivariate analyses. The results echo many traditional observations, while also showing that most diagnostic leaf features remain undescribed. CONCLUSIONS Machine-derived heat maps that initially appear to be dominated by noise can be translated into human-interpretable knowledge, highlighting paths forward for botanists and paleobotanists to discover new diagnostic botanical characters.
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Affiliation(s)
- Edward J Spagnuolo
- Department of Geosciences and Earth and Environmental Systems Institute, Pennsylvania State University, University Park, Pennsylvania, 16802, USA
- Millennium Scholars Program, Pennsylvania State University, University Park, Pennsylvania, 16802, USA
- Schreyer Honors College, Pennsylvania State University, University Park, Pennsylvania, 16802, USA
| | - Peter Wilf
- Department of Geosciences and Earth and Environmental Systems Institute, Pennsylvania State University, University Park, Pennsylvania, 16802, USA
| | - Thomas Serre
- Department of Cognitive, Linguistic and Psychological Sciences, Carney Institute for Brain Science, Brown University, Providence, Rhode Island, 02912, USA
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Zhou M, Guo Y, Sheng J, Yuan Y, Zhang WH, Bai W. Using anatomical traits to understand root functions across root orders of herbaceous species in a temperate steppe. New Phytol 2022; 234:422-434. [PMID: 35048364 DOI: 10.1111/nph.17978] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [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: 11/14/2021] [Accepted: 01/03/2022] [Indexed: 06/14/2023]
Abstract
Root anatomical traits play crucial roles in understanding root functions and root form-function linkages. However, the root anatomy and form-function linkages of monocotyledonous and dicotyledonous herbs remain largely unknown. We measured order-based anatomical traits and mycorrhizal colonization rates of 32 perennial herbs of monocotyledons and dicotyledons in a temperate steppe. For monocots, relative constant proportion of cortex and mycorrhizal colonization rates, but increased cell-wall thickening of the endodermis and proportion of stele were observed across root orders, indicating a slight reduction in absorption capacity and improvement in transportation capacity across orders. For dicots, the cortex and mycorrhizal colonization disappeared in the fourth-order and/or fifth-order roots, whereas the secondary vascular tissue increased markedly, suggesting significant transition of root functions from absorption to transportation across root orders. The allometric relationships between stele and cortex differed across root orders and plant groups, suggesting different strategies to coordinate the absorption and transportation functions among plant groups. In summary, our results revealed different functional transition patterns across root orders and distinct strategies for coordinating the absorption and transportation of root system between monocots and dicots. These findings will contribute to our understanding of the root form and functions in herbaceous species.
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Affiliation(s)
- Meng Zhou
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China
| | - Yumeng Guo
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jun Sheng
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yujia Yuan
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wen-Hao Zhang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wenming Bai
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China
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Sajjad A, Liu J, Wang Y, Farooqi MA, Zhao Z, Ahmad A, Akram W, Ali M, Ali A. Plant communities exhibit low resource partitioning for pollinator guilds under sub-tropical conditions of Pakistan. PLoS One 2021; 16:e0247124. [PMID: 33606792 PMCID: PMC7894816 DOI: 10.1371/journal.pone.0247124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 02/01/2021] [Indexed: 12/05/2022] Open
Abstract
Assessment of resource partitioning in pollinators at a particular place can be used to conserve plant communities by minimizing their inter-specific competition. Current study was conducted to investigate the occurrence of this phenomenon among plant communities under sub-tropical conditions for the first time in Pakistan. We considered the entire available flowering plant and floral visitor communities in the study area-Lal Suhanra forest of Bahawalpur, Pakistan- along with different variations among them based on morphology, color and symmetry (functional groups) i.e. four functional groups among insects and nine among plants. Weekly floral visitor censuses were conducted during spring season -from the first week of March to the fourth week of May 2018. Thirty individuals of each plant species -in bloom- were observed for floral visitors in each census. Plant species with different floral shapes, colors and symmetry did not show any significant resource partitioning. The Non-metric multidimensional scaling analysis followed by one-way ANOSIM test showed non- significant differences among all the pair of floral shapes, colors (except white and yellow) and symmetry (R-value < 0.168). However, SIMPER test suggested that flies were the most common group that contributed more towards within group similarities of different floral shapes (19 to 21% similarity), colors (16 to 30%) and symmetry (19%) followed by long-tongue bees i.e. 14 to 21%, 9 to 19% and 18%, respectively. Our results suggest that plant communities under sub-tropical conditions of Pakistan exhibit a generalist pollination system with no significant resource partitioning in pollinator species. Therefore, plant communities may have high competition for pollinator species which exhibits fewer implications of species loss on overall pollination process. Our study provides the basis for understanding the partitioning of pollinator guilds under sub-tropical conditions. Future studies should focus on functional traits in more detail at the community and the population scales for their possible impact on resource partitioning.
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Affiliation(s)
- Asif Sajjad
- Department of Entomology, Faculty of Agriculture and Environment, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Junhe Liu
- College of Biological and Food Engineering, Huanghuai University, Zhumadian, Henan, China
| | - Yusha Wang
- Université Côte d’Azur, INRAE, CNRS, UMR ISA, Nice, France
| | - Muhammad Aslam Farooqi
- Department of Entomology, Faculty of Agriculture and Environment, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Zihua Zhao
- Department of Entomology, College of Plant Protection, China Agricultural University, Beijing, China
| | - Ammad Ahmad
- Department of Entomology, Faculty of Agriculture and Environment, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Waseem Akram
- Department of Entomology, Faculty of Agriculture and Environment, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Mudssar Ali
- Department of Entomology, Muhammad Nawaz Sharif University of Agriculture, Multan, Pakistan
| | - Abid Ali
- College of Life Science, Shenyang Normal University, Shenyang, Liaoning, China
- Department of Entomology, University of Agriculture, Faisalabad, Pakistan
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Ziemińska K, Rosa E, Gleason SM, Holbrook NM. Wood day capacitance is related to water content, wood density, and anatomy across 30 temperate tree species. Plant Cell Environ 2020; 43:3048-3067. [PMID: 32935340 DOI: 10.1111/pce.13891] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [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: 09/11/2019] [Revised: 09/05/2020] [Accepted: 09/07/2020] [Indexed: 06/11/2023]
Abstract
Water released from wood during transpiration (capacitance) can meaningfully affect daily water use and drought response. To provide context for better understanding of capacitance mechanisms, we investigated links between capacitance and wood anatomy. On twigs of 30 temperate angiosperm tree species, we measured day capacitance (between predawn and midday), water content, wood density, and anatomical traits, that is, vessel dimensions, tissue fractions, and vessel-tissue contact fractions (fraction of vessel circumference in contact with other tissues). Across all species, wood density (WD) and predawn lumen volumetric water content (VWCL-pd ) together were the strongest predictors of day capacitance (r2adj = .44). Vessel-tissue contact fractions explained an additional ~10% of the variation in day capacitance. Regression models were not improved by including tissue lumen fractions. Among diffuse-porous species, VWCL-pd and vessel-ray contact fraction together were the best predictors of day capacitance, whereas among semi/ring-porous species, VWCL-pd , WD and vessel-fibre contact fraction were the best predictors. At predawn, wood was less than fully saturated for all species (lumen relative water content = 0.52 ± 0.17). Our findings imply that day capacitance depends on the amount of stored water, tissue connectivity and the bulk wood properties arising from WD (e.g., elasticity), rather than the fraction of any particular tissue.
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Affiliation(s)
- Kasia Ziemińska
- Arnold Arboretum of Harvard University, Boston, Massachusetts, USA
- Department of Plant Ecology and Evolution, Uppsala University, Uppsala, Sweden
| | - Emily Rosa
- Department of Biology, Sonoma State University, Rohnert Park, California, USA
| | - Sean M Gleason
- United States Department of Agriculture - Agricultural Research Service, Water Management and Systems Research Unit, Fort Collins, Colorado, USA
| | - N Michele Holbrook
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
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Xie D, Chen L, Zhou C, Tarin MWK, Yang D, Ren K, He T, Rong J, Zheng Y. Transcriptomic and metabolomic profiling reveals the effect of LED light quality on morphological traits, and phenylpropanoid-derived compounds accumulation in Sarcandra glabra seedlings. BMC Plant Biol 2020; 20:476. [PMID: 33076818 PMCID: PMC7574309 DOI: 10.1186/s12870-020-02685-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [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: 05/05/2020] [Accepted: 10/07/2020] [Indexed: 06/01/2023]
Abstract
BACKGROUND Sarcandra glabra is an evergreen and traditional Chinese herb with anti-oxidant, anti-bacterial, anti-inflammatory, and anti-tumor effects. Light is one of the most influential factor affecting the growth and quality of herbs. In recent times, the introduction of Light Emission Diode (LED) technology has been widely used for plants in greenhouse. However, the impact of such lights on plant growth and the regulatory mechanism of phenylpropanoid-derived compounds in S. glabra remain unclear. RESULTS The red LED light (RL) substantially increased the plant height and decreased the stem diameter and leaf area relative to the white LED light (WL), while the blue LED light (BL) significantly reduced the height and leaf area of S. glabra. According to transcriptomic profiling, 861, 378, 47, 10,033, 7917, and 6379 differentially expressed genes (DEGs) were identified among the groups of leaf tissue under BL (BY) vs. leaf tissue under RL (RY), BY vs. leaf tissue under WL (WY), RY vs. WY, root tissue under WL (WG) vs. WY, stem tissue under WL (WJ) vs. WG, and WJ vs. WY, respectively. We identified 46 genes encoding for almost all known enzymes involved in phenylpropanoid biosynthesis, e.g., phenylalanine ammonia lyase (PAL), chalcone synthase (CHS), and flavonol synthase (FLS). We found 53 genes encoding R2R3-MYB proteins and bHLH proteins, respectively, where several were related to flavonoids biosynthesis. A total of 454 metabolites were identified based on metabolomic profiling, of which 44, 87, and 296 compounds were differentially produced in WY vs. RY, WY vs. BY, and WY vs. WG. In BY there was a substantial reduction in the production of esculetin, caffeic acid, isofraxidin, and fraxidin, while the yields of quercitrin and kaempferol were significantly up-regulated. In RY, the contents of cryptochlorogenic acid, cinnamic acid, and kaempferol decreased significantly. Besides, in WG, the production of metabolites (e.g. chlorogenic acid, cryptochlorogenic acid, and scopolin) declined, while their yields increased significantly (e.g. esculetin, fraxetin, isofraxidin, and fraxidin). CONCLUSION These results provide further insight into the regulatory mechanism of accumulation patterns of phenylpropanoid-derived compounds in S. glabra under various light conditions, allowing optimum breeding conditions to be developed for this plant.
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Affiliation(s)
- Dejin Xie
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Lingyan Chen
- College of Arts & College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Chengcheng Zhou
- College of Arts & College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Muhammad Waqqas Khan Tarin
- College of Arts & College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Deming Yang
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Ke Ren
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Tianyou He
- College of Arts & College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Jundong Rong
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Yushan Zheng
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
- College of Arts & College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
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Johnson KM, Brodersen C, Carins-Murphy MR, Choat B, Brodribb TJ. Xylem Embolism Spreads by Single-Conduit Events in Three Dry Forest Angiosperm Stems. Plant Physiol 2020; 184:212-222. [PMID: 32581116 PMCID: PMC7479884 DOI: 10.1104/pp.20.00464] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 06/15/2020] [Indexed: 05/02/2023]
Abstract
Xylem cavitation resulting in air embolism is a major cause of plant death during drought, yet the spread of embolism throughout the plant water transport system is poorly understood. Our study used optical visualization and x-ray microcomputed tomography imaging to capture the spread of emboli in stems of three drought-resistant angiosperm trees: drooping she-oak (Allocasuarina verticillata), black wattle (Acacia mearnsii), and blue gum (Eucalyptus globulus). These species have similar degrees of xylem network connectivity (vessel grouping) with largely solitary vessels. The high temporal resolution of the optical vulnerability technique revealed that in current year branches, >80% of the cavitation events were discrete, temporally separated events in single vessels. This suggests that in xylem networks with low connectivity, embolism spread between conduits leading to multiple conduit cavitation events is uncommon. A. mearnsii showed both the highest number of multivessel cavitation events and the highest degree of vessel connectivity, suggesting a link between vessel arrangement and embolism spread. Knowledge of embolism spread will help us to uncover the links between xylem anatomy, arrangement, and the path of water flow in the xylem in diverse species to ultimately understand the drivers of cavitation and plant vulnerability to drought.
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Affiliation(s)
- Kate M Johnson
- Discipline of Biological Sciences, School of Natural Sciences, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Craig Brodersen
- School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511
| | - Madeline R Carins-Murphy
- Discipline of Biological Sciences, School of Natural Sciences, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Brendan Choat
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales 2750, Australia
| | - Timothy J Brodribb
- Discipline of Biological Sciences, School of Natural Sciences, University of Tasmania, Hobart, Tasmania 7001, Australia
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13
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Mursidawati S, Wicaksono A, Teixeira da Silva JA. Rafflesia patma Blume flower organs: histology of the epidermis and vascular structures, and a search for stomata. Planta 2020; 251:112. [PMID: 32494866 DOI: 10.1007/s00425-020-03402-5] [Citation(s) in RCA: 2] [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: 03/16/2020] [Accepted: 05/18/2020] [Indexed: 05/27/2023]
Abstract
A histological study of Rafflesia patma revealed the simplicity of a flower's vascular tissue and epidermal features of flower organs, including their structures and pigmentation. Rafflesia is an endophytic holoparasitic plant that infects Tetrastigma. In a previous study, we characterized the shape of the strands of an endophyte (Rafflesia patma Blume) and hypothesized their distribution. In this study, we deepened our analysis by assessing parts of flower tissue sampled during anthesis, performed surface casting of the abaxial and adaxial sides of the perigone lobe to profile their surface features, and histologically characterized the perigone lobe, perigone tube, and central column base, including the anther and cupula region. The objective of these observations was to compare tissues from different organs and the distribution of cells staining positive for tannin, suberin, and lignin. Observable features in this study were vascular and epidermal tissue. We also observed reduced vascular tissue with xylem and vascular parenchyma in multiple organs. The adaxial epidermis found in the perigone lobes and tube had papillate cells, and their function might be to assist with the emission of odor through chemical evaporation. The abaxial epidermis, also found in perigone lobes and tube, had flattened cells. These, combined with the nearby flattened parenchyma cells, especially in the outermost, early perigone lobe, might provide a tougher (stiffer) outer protective barrier for the flower. The accumulation of tannin in perigone lobes might offer protection to the flower from herbivores prior to anthesis. Although a previous observation indicated the possibility of stomata on the surface of Rafflesia flowers, no stomata were found in this study.
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Affiliation(s)
- Sofi Mursidawati
- Center of Plant Conservation, Bogor Botanical Garden, Indonesian Institute of Science (LIPI), Jl. Ir. H. Juanda no.13, Bogor, 16003, Indonesia.
| | - Adhityo Wicaksono
- Division of Biotechnology, Generasi Biologi Indonesia (Genbinesia) Foundation, Jl. Swadaya Barat no. 4, Gresik Regency, 61171, Indonesia.
| | - Jaime A Teixeira da Silva
- Independent Researcher, Miki-cho post office, Ikenobe 3011-2, P.O. Box 7, Shikoku, Kagawa-ken, 761-0799, Japan
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14
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Reut MS, Płachno BJ. Unusual developmental morphology and anatomy of vegetative organs in Utricularia dichotoma-leaf, shoot and root dynamics. Protoplasma 2020; 257:371-390. [PMID: 31659470 PMCID: PMC7039851 DOI: 10.1007/s00709-019-01443-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [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: 05/05/2019] [Accepted: 09/19/2019] [Indexed: 05/05/2023]
Abstract
The terrestrial carnivorous species Utricularia dichotoma is known for a great phenotypic plasticity and unusual vegetative organs. Our investigation on 22 sources/populations revealed that after initiation of a leaf and two bladders on a stolon, a bud was formed in the proximal axil of the leaf, developing into a rosette with up to seven organs. The first two primordia of the bud grew into almost every possible combination of organs, but often into two anchor stolons. The patterns were generally not population specific. The interchangeability of organs increased with increasing rank in the succession of organs on stolon nodes. A high potential of switching developmental programs may be successful in a fluctuating environment. In this respect, we were able to show that bladders developed from anchor stolons experimentally when raising the water table. Anatomical structures were simple, lacunate and largely homogenous throughout all organs. They showed similarities with many hydrophytes, reflecting the plant's adaptation to (temporarily) submerged conditions. The principal component analysis was used in the context of dynamic morphology to illustrate correlations between organ types in the morphospace of U. dichotoma, revealing an organ specific patchwork of developmental processes for typical leaves and shoots, and less pronounced for a typical root. The concept and methods we applied may prove beneficial for future studies on the evolution of Lentibulariaceae, and on developmental morphology and genetics of unusual structures in plants.
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Affiliation(s)
- Markus S Reut
- Department of Plant Cytology and Embryology, Institute of Botany, Faculty of Biology, Jagiellonian University, Kraków, 9 Gronostajowa St, 30-387, Cracow, Poland.
| | - Bartosz J Płachno
- Department of Plant Cytology and Embryology, Institute of Botany, Faculty of Biology, Jagiellonian University, Kraków, 9 Gronostajowa St, 30-387, Cracow, Poland
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15
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Genise JF, Bellosi ES, Sarzetti LC, Krause JM, Dinghi PA, Sánchez MV, Umazano AM, Puerta P, Cantil LF, Jicha BR. 100 Ma sweat bee nests: Early and rapid co-diversification of crown bees and flowering plants. PLoS One 2020; 15:e0227789. [PMID: 31995815 PMCID: PMC6989152 DOI: 10.1371/journal.pone.0227789] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 12/25/2019] [Indexed: 02/06/2023] Open
Abstract
100 Ma sweat bee nests reported herein are the oldest evidence of crown bees. A new phylogeny for short-tongued bees, calibrated with these nests dated with 40Ar/39Ar, attests for the first time for a late Albian rapid diversification of bees along with angiosperms. Such hypothesis lacked paleontological support until this study. The new ichnospecies Cellicalichnus krausei, which was found along with wasp trace fossils and new beetle trace fossils in the Castillo Formation of Patagonia, represents typical Halictini nests composed of sessile cells that are attached to main tunnels. According to geological, paleosol, paleobotanical, and ichnological data, bees, and angiosperms cohabited in an inland and dry environment comparable to an open dry woodland or savanna, under warm-temperate and semiarid-subhumid climate, in the Southern Hemisphere by the Albian.
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Affiliation(s)
- Jorge Fernando Genise
- División Icnología, CONICET-Museo Argentino de Ciencias Naturales Bernardino Rivadavia, Buenos Aires, Argentina
- * E-mail:
| | - Eduardo S. Bellosi
- División Icnología, CONICET-Museo Argentino de Ciencias Naturales Bernardino Rivadavia, Buenos Aires, Argentina
| | - Laura C. Sarzetti
- División Icnología, CONICET-Museo Argentino de Ciencias Naturales Bernardino Rivadavia, Buenos Aires, Argentina
| | | | - Pablo A. Dinghi
- Grupo de Investigación en Filogenias Moleculares y Filogeografía, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - M. Victoria Sánchez
- División Icnología, CONICET-Museo Argentino de Ciencias Naturales Bernardino Rivadavia, Buenos Aires, Argentina
| | - A. Martín Umazano
- INCITAP and Facultad de Ciencias Exactas y Naturales, CONICET-Universidad Nacional de La Pampa, Santa Rosa, La Pampa, Argentina
| | - Pablo Puerta
- Museo Paleontológico Egidio Feruglio, Trelew, Chubut, Argentina
| | - Liliana F. Cantil
- División Icnología, CONICET-Museo Argentino de Ciencias Naturales Bernardino Rivadavia, Buenos Aires, Argentina
| | - Brian R. Jicha
- Department of Geoscience, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
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16
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Abstract
Several recent palaeobotanical studies claim to have found and described pre-Cretaceous angiosperm macrofossils. With rare exceptions, these papers fail to define a flower, do not acknowledge that fossils require character-based rather than group-based classification, do not explicitly state which morphological features would unambiguously identify a fossil as angiospermous, ignore the modern conceptual framework of phylogeny reconstruction, and infer features in the fossils in question that are interpreted differently by (or even invisible to) other researchers. This unfortunate situation is compounded by the relevant fossils being highly disarticulated two-dimensional compression-impressions lacking anatomical preservation. Given current evidence, all supposed pre-Cretaceous angiosperms are assignable to other major clades among the gymnosperms sensu lato. By any workable morphological definition, flowers are not confined to, and therefore cannot delimit, the angiosperm clade. More precisely defined character states that are potentially diagnostic of angiosperms must by definition originate on the phylogenetic branch that immediately precedes the angiosperm crown group. Although the most reliable candidates for diagnostic characters (triploid endosperm reflecting double fertilization, closed carpel, bitegmic ovule, and phloem companion cells) are rarely preserved and/or difficult to detect unambiguously, similar characters have occasionally been preserved in high-quality permineralized non-angiosperm fossils. The angiosperm radiation documented by Early Cretaceous fossils involves only lineages closely similar to extant taxonomic families, lacks obvious morphological gaps, and (as agreed by both the fossil record and molecular phylogenies) was relatively rapid-all features that suggest a primary radiation. It is unlikely that ancestors of the crown group common ancestor would have fulfilled a character-based definition of (and thereby required expansion of the concept of) an angiosperm; they would instead form a new element of the non-angiosperm members of the 'anthophyte' grade, competing with Caytonia to be viewed as morphologically determined sister group for angiosperms. Conclusions drawn from molecular phylogenetics should not be allowed to routinely constrain palaeobotanical inferences; reciprocal illumination between different categories of data offers greater explanatory power than immediately resorting to Grand Syntheses. The Jurassic angiosperm-essentially a product of molecular phylogenetics-may have become the holy grail of palaeobotany but it appears equally mythical.
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17
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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. New Phytol 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] [What about the content of this article? (0)] [Affiliation(s)] [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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18
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Xin GL, Liu JQ, Liu J, Ren XL, Du XM, Liu WZ. Anatomy and RNA-Seq reveal important gene pathways regulating sex differentiation in a functionally Androdioecious tree, Tapiscia sinensis. BMC Plant Biol 2019; 19:554. [PMID: 31842763 PMCID: PMC6915933 DOI: 10.1186/s12870-019-2081-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [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: 08/10/2018] [Accepted: 10/16/2019] [Indexed: 05/07/2023]
Abstract
BACKGROUND Gametogenesis is a key step in the production of ovules or pollen in higher plants. The sex-determination aspects of gametogenesis have been well characterized in the model plant Arabidopsis. However, little is known about this process in androdioecious plants. Tapiscia sinensis Oliv. is a functionally androdioecious tree, with both male and hermaphroditic individuals. Hermaphroditic flowers (HFs) are female-fertile flowers that can produce functional pollen and set fruits. However, compared with male flowers (MFs), the pollen viability and number of pollen grains per flower are markedly reduced in HFs. MFs are female-sterile flowers that fail to set fruit and that eventually drop. RESULTS Compared with HF, a notable cause of MF female sterility in T. sinensis is when the early gynoecium meristem is disrupted. During the early stage of HF development (stage 6), the ring meristem begins to form as a ridge around the center of the flower. At this stage, the internal fourth-whorl organ is stem-like rather than carpelloid in MF. A total of 52,945 unigenes were identified as transcribed in MF and HF. A number of differentially expressed genes (DEGs) and metabolic pathways were detected as involved in the development of the gynoecium, especially the ovule, carpel and style. At the early gynoecium development stage, DEGs were shown to function in the metabolic pathways regulating ethylene biosynthesis and signal transduction (upstream regulator), auxin, cytokinin transport and signalling, and sex determination (or flower meristem identity). CONCLUSIONS Pathways for the female sterility model were initially proposed to shed light on the molecular mechanisms of gynoecium development at early stages in T. sinensis.
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Affiliation(s)
- Gui-Liang Xin
- Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, School of Life Science, Northwest University, Xi’an, 710069 Shaanxi China
| | - Jia-Qian Liu
- Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, School of Life Science, Northwest University, Xi’an, 710069 Shaanxi China
| | - Jia Liu
- Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, School of Life Science, Northwest University, Xi’an, 710069 Shaanxi China
| | - Xiao-Long Ren
- Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, School of Life Science, Northwest University, Xi’an, 710069 Shaanxi China
| | - Xiao-Min Du
- Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, School of Life Science, Northwest University, Xi’an, 710069 Shaanxi China
| | - Wen-Zhe Liu
- Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, School of Life Science, Northwest University, Xi’an, 710069 Shaanxi China
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19
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Jameson PE, Clemens J. Phase change and flowering in woody plants of the New Zealand flora. J Exp Bot 2019; 70:e6488-e6495. [PMID: 26512056 PMCID: PMC6859511 DOI: 10.1093/jxb/erv472] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 10/08/2015] [Indexed: 06/05/2023]
Abstract
Heteroblastic and homoblastic woody plants from the New Zealand flora provide a rich playground for testing hypotheses relating to phase change and flowering.
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Affiliation(s)
- Paula E Jameson
- School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - John Clemens
- School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
- Christchurch Botanic Gardens, Christchurch City Council, Christchurch, New Zealand
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20
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Su H, Chen J, Wu Y, Chen J, Guo X, Yan Z, Tian D, Fang J, Xie P. Morphological traits of submerged macrophytes reveal specific positive feedbacks to water clarity in freshwater ecosystems. Sci Total Environ 2019; 684:578-586. [PMID: 31158621 DOI: 10.1016/j.scitotenv.2019.05.267] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [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: 01/21/2019] [Revised: 05/15/2019] [Accepted: 05/18/2019] [Indexed: 06/09/2023]
Abstract
Positive feedbacks are generally related to the interactions between biotic processes and abiotic drivers and may lead to the emergence of alternative stable states in ecosystems. Understanding the mechanisms of self-reinforcing feedbacks in a macrophyte-dominant clear state is critical for lake management. Based on a survey of 35 lakes in the Yangtze River floodplain and canonical correspondence analysis (CCA) with forward selection, the results showed that water clarity is the most limiting factor that influences the community structure and biomass of submerged macrophytes. The canopy length of tall macrophytes (i.e., Myriophyllum spicatum L. and Potamogeton malaianus Miq.) showed positive allometry with plant height, while the canopy length of small macrophytes (e.g., Potamogeton maackianus A. Benn.) showed isometry. Our results indicated the existence of positive feedbacks between macrophyte vegetation and water clarity in a "more vegetation, higher water clarity" pattern. We found that the relationships between monospecific community biomass and water clarity differed among community types, indicating that the strength of the positive feedback was interspecific. Furthermore, we found significant differences in the Secchi depth (SD), chlorophyll a (Chl a), light attenuation coefficient (K) and dissolved oxygen (DO) associated with monospecific macrophyte patches. Plant height had significant relationships with the mean values of SD, Chl a, total phosphorus (TP) and K, suggesting that plant height was one of the mechanisms underlying the positive feedbacks. In management practices, efforts to build and maintain the resilience of an ecosystem should be trait-based rather than merely focusing on vegetation abundance.
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Affiliation(s)
- Haojie Su
- Department of Ecology, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China; Donghu Experimental Station of Lake Ecosystems, State key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072, China
| | - Jun Chen
- Donghu Experimental Station of Lake Ecosystems, State key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072, China
| | - Yao Wu
- Donghu Experimental Station of Lake Ecosystems, State key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072, China
| | - Jianfeng Chen
- Poyang Lake Eco-economy Research Center, Jiujiang University, Jiujiang 332005, China
| | - Xiaochun Guo
- National Engineering Laboratory for Lake Pollution Control and Ecological Restoration, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Zhengbing Yan
- Department of Ecology, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Di Tian
- College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Jingyun Fang
- Department of Ecology, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Ping Xie
- Donghu Experimental Station of Lake Ecosystems, State key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072, China.
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Abstract
Islands have remarkable levels of endemism and contribute greatly to global biodiversity. Establishing the age of island endemics is important to gain insights into the processes that have shaped the biodiversity patterns of island biota. We investigated the relative age of monocots across islands worldwide, using different measures of phylogenetic endemism tested against null models. We compiled a species occurrence dataset across 4,306 islands, and identified 142 sites with neo-, paleo-, mixed and super-endemism. These sites were distributed across the world, although they tended to be more common at low latitudes. The most frequent types of endemism were mixed and super-endemism, which suggests that present-day island biodiversity has frequently been shaped by processes that took place at different points in times. We also identified the environmental factors that contributed most to different types of endemism; we found that latitude, habitat availability and climate stability had a significant impact on the persistence of ancient taxa and on recent diversification events. The islands identified here are irreplaceable both for the uniqueness and the evolutionary history of their flora, and because they are a source of "option values" and evolutionary potential. Therefore, our findings will help guide biodiversity conservation on a global scale.
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Affiliation(s)
- Simon Veron
- Institut de Systématique, Evolution, Biodiversité (ISYEB UMR 7205), Muséum National d'Histoire Naturelle (MNHN), CNRS, Sorbonne Université, EPHE, CP 51, 47 rue Buffon, 75005, Paris, France.
- Centre d'Ecologie et des Sciences de la Conservation (CESCO UMR 7204) MNHN, CNRS, Sorbonne Université - CP51, 55-61 rue Buffon, 75005, Paris, France.
| | - Thomas Haevermans
- Institut de Systématique, Evolution, Biodiversité (ISYEB UMR 7205), Muséum National d'Histoire Naturelle (MNHN), CNRS, Sorbonne Université, EPHE, CP 51, 47 rue Buffon, 75005, Paris, France
| | | | - Maud Mouchet
- Centre d'Ecologie et des Sciences de la Conservation (CESCO UMR 7204) MNHN, CNRS, Sorbonne Université - CP51, 55-61 rue Buffon, 75005, Paris, France
| | - Roseli Pellens
- Institut de Systématique, Evolution, Biodiversité (ISYEB UMR 7205), Muséum National d'Histoire Naturelle (MNHN), CNRS, Sorbonne Université, EPHE, CP 51, 47 rue Buffon, 75005, Paris, France
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22
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Sun W, Yuan X, Liu ZJ, Lan S, Tsai WC, Zou SQ. Multivariate analysis reveals phenotypic diversity of Euscaphis japonica population. PLoS One 2019; 14:e0219046. [PMID: 31310621 PMCID: PMC6634381 DOI: 10.1371/journal.pone.0219046] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 06/16/2019] [Indexed: 11/21/2022] Open
Abstract
Fruit traits affect population genetic diversity by affecting seed protection and dispersal strategies, thereby comprising important components of phenotypic variation. Understanding of the phenotypic variation is an indispensable first step for developing breeding strategies. However, little information is known about the genetic variation in E. japonica-a monotypic species with abundant phenotypes that is mainly distributed in southern China. In this study, we evaluated the phenotypic diversity of 67 E. japonica using 23 phenotypic traits. Our results showed that the Shannon-Wiener (I) index of qualitative traits ranged from 0.55 to 1.26, and the color traits had a relatively high I. The average coefficient of variation of compound leaf traits (14.74%) was higher than that of fruit and seed traits (12.77% and 11.47%, respectively). Principal component analysis also showed that compound leaf and fruit traits were important components of total variation. Furthermore, correlation analysis revealed a significant difference in elevation and fruit color, irregular ribs, leaf margin and texture. The F value within populations was smaller than among populations, indicating the variation in phenotypic traits among populations was much greater than within populations. Dehua and Zunyi populations had the highest coefficients of variation, whereas Wenzhou population had the smallest-which may be attributed to habitat destruction. According to Q-type clustering, 67 samples clustered into four groups, with those having similar phenotypes clustering into the same group. In general, leaf and fruit traits had abundant phenotypic diversity, representing the main sources of phenotypic variation. Combined with clustering results and field surveys, this study suggests that the phenotypes of E. japonica are classified into two main categories: The deciduous E. japonica present at high altitudes; and the evergreen E. japonica present at low altitudes. Excavating E. japonica variations provides a theoretical reference for its classification and diversity, and is of great significance for planning genetic resources and establishing conservation strategies.
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Affiliation(s)
- Weihong Sun
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, China
- Fujian Colleges and Universities Engineering Research Institute of Conservation and Utilization of Natural Bioresources, College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at Colleage of Landscape Architecture, College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou, China
- Ornamental Plant Germplasm Resources Innovation and Engineering Application Research Center, College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xueyan Yuan
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, China
- Fujian Colleges and Universities Engineering Research Institute of Conservation and Utilization of Natural Bioresources, College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at Colleage of Landscape Architecture, College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou, China
- Ornamental Plant Germplasm Resources Innovation and Engineering Application Research Center, College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Zhong-Jian Liu
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at Colleage of Landscape Architecture, College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Siren Lan
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, China
- Fujian Colleges and Universities Engineering Research Institute of Conservation and Utilization of Natural Bioresources, College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at Colleage of Landscape Architecture, College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou, China
- Ornamental Plant Germplasm Resources Innovation and Engineering Application Research Center, College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Wen-chieh Tsai
- Department of Biological Sciences and Technology, National University of Tainan, Tainan, Taiwan, China
| | - Shuang-Quan Zou
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, China
- Fujian Colleges and Universities Engineering Research Institute of Conservation and Utilization of Natural Bioresources, College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at Colleage of Landscape Architecture, College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou, China
- Ornamental Plant Germplasm Resources Innovation and Engineering Application Research Center, College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou, China
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23
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Coiffard C, Kardjilov N, Manke I, Bernardes-de-Oliveira MEC. Fossil evidence of core monocots in the Early Cretaceous. Nat Plants 2019; 5:691-696. [PMID: 31285562 DOI: 10.1038/s41477-019-0468-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 06/04/2019] [Indexed: 05/11/2023]
Abstract
All the major clades of angiosperms have a fossil record that extends back to more than 100 million years ago (Early Cretaceous), mostly in agreement with molecular dating. However, the Early Cretaceous record of monocots is very poor compared to other angiosperms. Their herbaceous nature has been invoked to explain this rarity, but biogeography could also be an explanation. Unfortunately, most of the Early Cretaceous angiosperm record comes from northern mid-latitudes. The Crato plattenkalk limestone offers a unique window into the Early Cretaceous vegetation of the tropics and has already yielded monocot fossils. Here, we describe a whole monocotyledonous plant from root to reproductive organs that is anatomically preserved. The good preservation of the fossils allowed the evaluation of reproductive, vegetative and anatomical characteristics of monocots, leading to a robust identification of this fossil as a crown monocot. Its occurrence in Northern Gondwana supports the possibility of an early radiation of monocots in the tropics.
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Affiliation(s)
- Clément Coiffard
- Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, Berlin, Germany.
| | - Nikolay Kardjilov
- Helmholtz-Center Berlin for Materials and Energy, Institute of Applied Materials, Berlin, Germany
| | - Ingo Manke
- Helmholtz-Center Berlin for Materials and Energy, Institute of Applied Materials, Berlin, Germany
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24
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Lu Z, Xie K, Pan Y, Ren T, Lu J, Wang M, Shen Q, Guo S. Potassium mediates coordination of leaf photosynthesis and hydraulic conductance by modifications of leaf anatomy. Plant Cell Environ 2019; 42:2231-2244. [PMID: 30938459 DOI: 10.1111/pce.13553] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [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: 09/18/2018] [Revised: 03/22/2019] [Accepted: 03/26/2019] [Indexed: 06/09/2023]
Abstract
Typical symptoms of potassium deficiency, characterized as chlorosis or withered necrosis, occur concomitantly with downregulated photosynthesis and impaired leaf water transport. However, the prominent limitations and mechanisms underlying the concerted decreases of leaf photosynthesis and hydraulic conductance are poorly understood. Monocots and dicots were investigated based on responses of photosynthesis and hydraulic conductance and their components and the correlated anatomical determinants to potassium deficiency. We found a conserved pattern in which leaf photosynthesis and hydraulic conductance concurrently decreased under potassium starvation. However, monocots and dicots showed two different hydraulic-redesign strategies: Dicots tended to show a decreased minor vein density, whereas monocots reduced the size of the bundle sheath and its extensions, rather than the minor vein density; both of these strategies may restrain xylem and outside-xylem hydraulic conductance. Additionally, potassium-deprived leaves developed with fewer mesophyll cell-to-cell connections, leading to a reduced area being available for liquid-phase flow. Further quantitative analysis revealed that mesophyll conductance to CO2 and outside-xylem hydraulic resistance were the major contributors to photosynthetic limitation and increased hydraulic resistance, at more than 50% and 60%, respectively. These results emphasize the importance of potassium in the coordinated regulation of leaf photosynthesis and hydraulic conductance through modifications of leaf anatomy.
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Affiliation(s)
- Zhifeng Lu
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, China
| | - Kailiu Xie
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yonghui Pan
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, China
| | - Tao Ren
- College of Resources and Environment, Huazhong Agricultural University, Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River) Ministry of Agriculture, Wuhan, 430070, China
| | - Jianwei Lu
- College of Resources and Environment, Huazhong Agricultural University, Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River) Ministry of Agriculture, Wuhan, 430070, China
| | - Min Wang
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, China
| | - Qirong Shen
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, China
| | - Shiwei Guo
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, China
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25
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Trueba S, Delzon S, Isnard S, Lens F. Similar hydraulic efficiency and safety across vesselless angiosperms and vessel-bearing species with scalariform perforation plates. J Exp Bot 2019; 70:3227-3240. [PMID: 30921455 DOI: 10.1093/jxb/erz133] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [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: 09/28/2018] [Accepted: 03/14/2019] [Indexed: 06/09/2023]
Abstract
The evolution of xylem vessels from tracheids is put forward as a key innovation that boosted hydraulic conductivity and photosynthetic capacities in angiosperms. Yet, the role of xylem anatomy and interconduit pits in hydraulic performance across vesselless and vessel-bearing angiosperms is incompletely known, and there is a lack of functional comparisons of ultrastructural pits between species with different conduit types. We assessed xylem hydraulic conductivity and vulnerability to drought-induced embolism in 12 rain forest species from New Caledonia, including five vesselless species, and seven vessel-bearing species with scalariform perforation plates. We measured xylem conduit traits, along with ultrastructural features of the interconduit pits, to assess the relationships between conduit traits and hydraulic efficiency and safety. In spite of major differences in conduit diameter, conduit density, and the presence/absence of perforation plates, the species studied showed similar hydraulic conductivity and vulnerability to drought-induced embolism, indicating functional similarity between both types of conduits. Interconduit pit membrane thickness (Tm) was the only measured anatomical feature that showed a relationship to significant vulnerability to embolism. Our results suggest that the incidence of drought in rain forest ecosystems can have similar effects on species bearing water-conducting cells with different morphologies.
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Affiliation(s)
- Santiago Trueba
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, 621 Charles E. Young Dr. South, Los Angeles, CA, USA
- AMAP, IRD, CIRAD, CNRS, INRA, Université de Montpellier, Nouméa, New Caledonia
| | | | - Sandrine Isnard
- AMAP, IRD, CIRAD, CNRS, INRA, Université de Montpellier, Nouméa, New Caledonia
| | - Frederic Lens
- Naturalis Biodiversity Center, Leiden University, Leiden, The Netherlands
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26
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Rümpler F, Theißen G. Reconstructing the ancestral flower of extant angiosperms: the 'war of the whorls' is heating up. J Exp Bot 2019; 70:2615-2622. [PMID: 30870567 DOI: 10.1093/jxb/erz106] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [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: 11/01/2018] [Accepted: 02/28/2019] [Indexed: 05/06/2023]
Abstract
The origin of the angiosperm flower is a long-standing problem of botany and evolutionary biology. One widely accepted milestone towards solving it is the reconstruction of the ancestral flower of extant angiosperms, here termed 'AFEA'. A recent approach employing novel methods gave results that were not anticipated. Most notably the reconstructed phyllotaxis of AFEA soon was criticized and sparked a heated debate in the literature. To better explain, clarify, and perhaps cool the debate, we first summarize the results of previous attempts to reconstruct AFEA and contrast them with the more recent, controversial prediction of its structure. We then outline the major arguments made by contrasting parties in the recent debate. Finally, we discuss two key topics, the molecular mechanism of phyllotaxis and the role of gene regulatory networks during flower development and evolution, that may help to clarify the issue in the intermediate future.
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Affiliation(s)
- Florian Rümpler
- Friedrich Schiller University Jena, Matthias Schleiden Institute - Genetics, Philosophenweg, Jena, Germany
| | - Günter Theißen
- Friedrich Schiller University Jena, Matthias Schleiden Institute - Genetics, Philosophenweg, Jena, Germany
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27
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Ehmig M, Coiro M, Linder HP. Ecophysiological strategy switch through development in heteroblastic species of mediterranean ecosystems - an example in the African Restionaceae. Ann Bot 2019; 123:611-623. [PMID: 30475945 PMCID: PMC6417474 DOI: 10.1093/aob/mcy194] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [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: 03/15/2018] [Accepted: 10/19/2018] [Indexed: 06/09/2023]
Abstract
BACKGROUND AND AIMS Heteroblasty is a non-reversible morphological change associated with life stage change and has been linked to predictable environmental variation. It is present in several clades from mediterranean-type climates, such as African Restionaceae (restios). These have heteroblastic shoots: juvenile shoots are thin, branched and sterile (sterile shoots); adult shoots are thicker and less branched, and bear inflorescences (reproductive shoots). Ten per cent of the restios retain juvenile-like, sterile shoots as adults (neoteny). We hypothesize (1) that the two shoot types differ in ecophysiological attributes, and (2) that these shoot types (and the neoteny) are associated with different environments. METHODS We measured shoot mass per surface area (SMA), maximum photosynthetic capacity per biomass (Amass) and chlorenchyma to ground tissue ratio (CGR) of both shoot types in 14 restio species. We also calculated environmental niche overlap between neotenous and non-neotenous species using an improved multidimensional overlap function based on occurrence data, and linked shoot types with environments using a phylogenetic generalized linear model. KEY RESULTS Sterile shoots showed higher Amass, lower SMA and higher CGR than reproductive shoots. Neotenous and non-neotenous species overlapped ecologically less than expected by chance: neotenous species favoured more mesic, non-seasonal conditions. CONCLUSIONS We associate sterile shoot morphology with acquisitive ecophysiological strategies and reproductive shoots with conservative strategies. The heteroblastic switch optimizes carbon efficiency in the juvenile phase (by sterile shoots) in the mesic post-fire conditions. The adult shoots present a compromise between a more conservative strategy favourable under harsher conditions and reproductive success. Heteroblasty in seasonally arid, oligotrophic ecosystems with predictable, fire-driven shifts in water and nutrient availability might play a role in the success of restios and other species-rich lineages in mediterranean-type ecosystems. It may represent a previously unrecognized adaptation in mediterranean clades sharing similar conditions, contributing to their ecological and taxonomic dominance.
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Affiliation(s)
- Merten Ehmig
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland
| | - Mario Coiro
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland
| | - H Peter Linder
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland
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28
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Medeiros JS, Lens F, Maherali H, Jansen S. Vestured pits and scalariform perforation plate morphology modify the relationships between angiosperm vessel diameter, climate and maximum plant height. New Phytol 2019; 221:1802-1813. [PMID: 30312484 DOI: 10.1111/nph.15536] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [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: 06/28/2018] [Accepted: 10/06/2018] [Indexed: 06/08/2023]
Abstract
Shared ancestry among species and correlation between vessel diameter and plant height can obscure the mechanisms linking vessel diameter to current climate distributions of angiosperms. Because wood is complex, various traits may interact to influence vessel function. Specifically, pit vesturing (lignified cell wall protuberances associated with bordered pits) and perforation plate morphology could alter the relationships between vessel diameter, climate and plant height. Using phylogenetically informed analyses, we tested for associations between vessel diameter, climate and maximum plant height across angiosperm species with different pit vesturing (presence/absence) and perforation plate morphology (simple/scalariform and quantitative variation). We show significantly larger changes in vessel diameter and maximum plant height across climates for species with vestures and simple perforation plates, compared to nonvestured species and those with scalariform plates. We also found a significantly greater increase in height for a given increase in vessel diameter with lower percentage of scalariform plates. Our study provides novel insights into the evolution of angiosperm xylem by showing that vessel pit vesturing and perforation plate morphologies can modify relationships among xylem vessels, climate and height. Our findings highlight the complexity of xylem adaptations to climate, substantiating an integrative view of xylem function in the study of wood evolution.
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Affiliation(s)
| | - Frederic Lens
- Naturalis Biodiversity Center, Leiden University, PO Box 9517, Leiden, 2300RA, the Netherlands
| | - Hafiz Maherali
- Department of Integrative Biology, University of Guelph, 50 Stone Road East, Guelph, ON, Canada, N1G 2W1
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 81, Ulm, 89081, Germany
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29
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Atkinson BA, Martínez C, Crepet WL. Cretaceous asterid evolution: fruits of Eydeia jerseyensis sp. nov. (Cornales) from the upper Turonian of eastern North America. Ann Bot 2019; 123:451-460. [PMID: 30212854 PMCID: PMC6377102 DOI: 10.1093/aob/mcy170] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [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: 03/21/2018] [Indexed: 05/27/2023]
Abstract
BACKGROUND AND AIMS The asterids (>80 000 extant species) appear in the fossil record with considerable diversity near the Turonian-Coniacian boundary (~90 Ma; Late Cretaceous) and are strongly represented in the earliest diverging lineage, Cornales. These early asterid representatives have so far been reported from western North America and eastern Asia. In this study, we characterize a new cornalean taxon based on charcoalified fruits from the upper Turonian of eastern North America, a separate landmass from western North America at the time, and identify early palaeobiogeographical patterns of Cornales during the Cretaceous. METHODS Fossils were studied and imaged using scanning electron microscopy and micro-computed tomography (micro-CT) scanning. To assess the systematic affinities of the fossils, phylogenetic analyses were conducted using maximum parsimony. KEY RESULTS The charcoalified fruits are represented by tri-locular woody endocarps with dorsal apically opening germination valves. Three septa intersect to form a robust central axis. Endocarp ground tissue consists of two zones: an outer endocarp composed of isodiametric sclereids and an inner endocarp containing circum-locular fibres. Central vasculature is absent; however, there are several small vascular bundles scattered within the septa. Phylogenetic analysis places the new taxon within the extinct genus Eydeia. DISCUSSION Thick-walled endocarps with apically opening germination valves, no central vascular bundle and one seed per locule are indicative of the order Cornales. Comparative analysis suggests that the fossils represent a new species, Eydeia jerseyensis sp. nov. This new taxon is the first evidence of Cornales in eastern North America during the Cretaceous and provides insights into the palaeobiogeography and initial diversification of the order.
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Affiliation(s)
- Brian A Atkinson
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS, USA
- Biodiversity Institute and Museum of Natural History, University of Kansas, Lawrence, KS, USA
| | - Camila Martínez
- L. H. Bailey Hortorium, Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, USA
| | - William L Crepet
- L. H. Bailey Hortorium, Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, USA
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30
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Armbruster WS, Wege JA. Detecting canalization and intra-floral modularity in triggerplant (Stylidium) flowers: correlations are only part of the story. Ann Bot 2019; 123:355-372. [PMID: 30383191 PMCID: PMC6344225 DOI: 10.1093/aob/mcy184] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [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: 06/28/2018] [Accepted: 09/18/2018] [Indexed: 05/25/2023]
Abstract
BACKGROUND AND AIMS The Berg hypothesis proposes that specialized-flower traits experience stronger stabilizing selection than non-floral structures and predicts that variation in specialized-flower traits will be mostly uncorrelated with variation in non-floral traits. Similarly, adaptive-accuracy theory predicts lower variation (as a proportion of the mean) in floral traits than in non-floral ones. Both hypotheses can be extended to comparisons between floral traits, where different parts of the flower can be expected to experience different strengths of stabilizing selection, resulting in contrasting patterns of variation. The present study tests these ideas by analysing variation/covariation in those floral traits influencing the location of pollen placement on, and stigma contact with, pollinators ('pollination-mechanics traits', PMTs) in relation to variation/covariation in non-floral traits and floral traits not directly involved in the mechanics of pollination. The prediction was that PMTs are canalized (buffered against genetic and environmental variation) relative to attraction traits, as manifested in lower variances and modular independence. METHODS Floral and inflorescence structures of ten species of triggerplants (Stylidium, Stylidiaceae) in south-western Australia were measured; the data were analysed using multivariate and bivariate approaches to detect modular structure of floral and non-floral traits and assess evidence for canalization of PMTs. KEY RESULTS Only six of the ten species had PMTs with smaller correlation coefficients than attraction traits, in contrast to the Berg expectation. However, allometric and variance patterns were generally consistent with the predictions of an extended Berg hypothesis and adaptive accuracy. There was modular separation of most floral traits from non-floral traits and clear intra-floral modular structure. PMTs showed lower proportional variation and shallower allometric slopes than pollinator-attraction traits in nine and eight, respectively, of ten species. CONCLUSIONS This study demonstrates the value of allometric and variance analyses (in addition to correlation) in assessing the evolutionary significance of floral-trait stability and plasticity.
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Affiliation(s)
- W Scott Armbruster
- School of Biological Sciences, University of Portsmouth, Portsmouth, UK
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK, USA
| | - Juliet A Wege
- Western Australian Herbarium, Biodiversity and Conservation Science, Department of Biodiversity, Conservation and Attractions, Bentley, Western Australia, Australia
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31
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Koi S, Won H, Kato M. Two new genera of Podostemaceae from northern Central Laos: saltational evolution and enigmatic morphology. J Plant Res 2019; 132:19-31. [PMID: 30623282 DOI: 10.1007/s10265-018-01082-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [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: 03/10/2018] [Accepted: 12/09/2018] [Indexed: 06/09/2023]
Abstract
Podostemaceae, the river-weeds, are characterized by remarkable differences between species and genera, which resulted from saltational evolution. This paper presents additional cases of such two genera, which are described here from the Phou Khao Khouay National Protected Area in northern Central Laos. Molecular phylogenetic data show that Ctenobryum mangkonense (gen. & sp. nov.) is sister to Hydrodiscus koyamae, while Laosia ramosa (gen. & sp. nov.) is isolated from all Asian genera of subfamily Podostemoideae. Ctenobryum mangkonense is distinct from Hydrodiscus koyamae in the crustose roots (versus rootless in the latter), scattered flowers on the root (versus alternate on the shoot), and pectinate bracts (versus simple, sheath-like). Laosia ramosa is distinct from all the genera in the columnar, endogenously branched axes and single style-stigma complex. The axis is an enigmatic organ with combined characteristics of root, stem and leaf, pending further study. Laos, together with Thailand, is a center of diversity of the Southeast and East Asian Podostemoideae. The three monotypic genera, i.e., Ctenobryum, Hydrodiscus and Laosia, occur in neighboring and closely similar aquatic habitats within the Area. The new taxa are formally described.
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Affiliation(s)
- Satoshi Koi
- Botanical Gardens, Faculty of Science, Osaka City University, Katano, Osaka, 576-0004, Japan.
| | - Hyosig Won
- Department of Biological Science, Daegu University, Gyungsan, Gyungbuk, 38453, Korea
| | - Masahiro Kato
- Department of Botany, National Museum of Nature and Science, Tsukuba, 305-0005, Japan
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32
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Bawa KS, Ingty T, Revell LJ, Shivaprakash KN. Correlated evolution of flower size and seed number in flowering plants (monocotyledons). Ann Bot 2019; 123:181-190. [PMID: 30165602 PMCID: PMC6344089 DOI: 10.1093/aob/mcy154] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [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: 08/18/2017] [Accepted: 07/24/2018] [Indexed: 06/08/2023]
Abstract
Background and Aims Kin selection theory predicts that a parent may minimize deleterious effects of competition among seeds developing within ovaries by increasing the genetic relatedness of seeds within an ovary. Alternatively, the number of developing seeds could be reduced to one or a few. It has also been suggested that single or few seeded fruits may be correlated with small flowers, and multi-ovulate ovaries or many seeded fruits may be associated with large flowers with specialized pollination mechanisms. We examined the correlation between flower size and seed number in 69 families of monocotyledons to assess if correlations are significant and independent of phylogeny. Methods We first examined the effect of phylogenetic history on the evolution of these two traits, flower size and seed number, and then mapped correlations between them on the latest phylogenetic tree of monocotyledons. Results The results provide phylogenetically robust evidence of strong correlated evolution between flower size and seed number and show that correlated evolution of traits is not constrained by phylogenetic history of taxa. Moreover, the two character combinations, small flowers and a single or few seeds per fruit, and large flowers and many seeded fruits, have persisted in monocotyledons longer than other trait combinations. Conclusions The analyses support the suggestion that most angiosperms may fall into two categories, one with large flowers and many seeded fruits and the other with small flowers and single or few seeded fruits, and kin selection within ovaries may explain the observed patterns.
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Affiliation(s)
- Kamaljit S Bawa
- Department of Biology, University of Massachusetts, Boston, MA, USA
- Ashoka Trust for Research in Ecology and the Environment, Bangalore, India
| | - Tenzing Ingty
- Department of Biology, University of Massachusetts, Boston, MA, USA
| | - Liam J Revell
- Department of Biology, University of Massachusetts, Boston, MA, USA
- Departamento de Ecología, Facultad de Ciencias, Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - K N Shivaprakash
- Ashoka Trust for Research in Ecology and the Environment, Bangalore, India
- Department of Biology, Concordia University, Montreal, Quebec, Canada
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da Costa FGCM, Klein DE, Philbrick CT, Bove CP. Silica bodies in leaves of neotropical Podostemaceae: taxonomic and phylogenetic perspectives. Ann Bot 2018; 122:1187-1201. [PMID: 30032254 PMCID: PMC6324752 DOI: 10.1093/aob/mcy121] [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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 06/20/2018] [Indexed: 06/08/2023]
Abstract
Background and Aims The presence, location and morphology of silica bodies are informative anatomical characters in angiosperms, mainly in Poales. In Podostemaceae, a strictly aquatic family, these structures are mentioned frequently, but there is limited insight into their location and morphological features. In the present study we focused on describing and analysing the morphological diversity of silica bodies in leaves of neotropical Podostemaceae at the intra- and interspecific levels to determine their taxonomic and phylogenetic relevance. Methods We studied 103 specimens distributed across 40 species. Silica body morphological traits were analysed under light and scanning electron microscopy. Additionally, data from three species of Hypericaceae (sister group) were retrieved from the literature. A phylogenetic framework based on four molecular markers was built in order to reconstruct ancestral character states related to silica bodies in neotropical Podostemaceae. Key Results Silica bodies were detected in epidermal, subepidermal and perivascular cells, presenting different shapes and surface morphology. Presence and location were used for primary differentiation while surface morphology and lumen (presence and shape) were used for finer distinctions. Intraspecific comparisons among samples showed that the length and width of these structures were highly variable. Maximum parsimony and maximum likelihood analyses for ancestral character reconstruction were congruent. Three out of five characters showed a statistically strong phylogenetic signal. Conclusions Silica bodies were reported for the first time for 19 taxa, and their morphological diversity is greater than reported in previous studies. Their presence can be considered an apomorphy in Podostemaceae. Although some significant differences were detected in length and width, qualitative characters are more informative at both specific and generic ranks.
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Affiliation(s)
- Filipe G C M da Costa
- Departamento de Botânica, Museu Nacional, Universidade Federal do Rio de Janeiro, Quinta da Boa Vista, Rio de Janeiro, RJ, Brazil
| | - Denise E Klein
- Departamento de Botânica, Universidade Federal do Estado do Rio de Janeiro, Urca, Rio de Janeiro, RJ, Brazil
| | - C Thomas Philbrick
- Department of Biological and Environmental Sciences, Western Connecticut State University, Danbury, CT, USA
| | - Claudia P Bove
- Departamento de Botânica, Museu Nacional, Universidade Federal do Rio de Janeiro, Quinta da Boa Vista, Rio de Janeiro, RJ, Brazil
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Mao Z, Wang Y, McCormack ML, Rowe N, Deng X, Yang X, Xia S, Nespoulous J, Sidle RC, Guo D, Stokes A. Mechanical traits of fine roots as a function of topology and anatomy. Ann Bot 2018; 122:1103-1116. [PMID: 29846521 PMCID: PMC6324743 DOI: 10.1093/aob/mcy076] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [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: 01/24/2018] [Accepted: 04/19/2018] [Indexed: 05/17/2023]
Abstract
Background and Aims Root mechanical traits, including tensile strength (Tr), tensile strain (εr) and modulus of elasticity (Er), are key functional traits that help characterize plant anchorage and the physical contribution of vegetation to landslides and erosion. The variability in these traits is high among tree fine roots and is poorly understood. Here, we explore the variation in root mechanical traits as well as their underlying links with morphological (diameter), architectural (topological order) and anatomical (stele and cortex sizes) traits. Methods We investigated the four tropical tree species Pometia tomentosa, Barringtonia fusicarpa, Baccaurea ramiflora and Pittosporopsis kerrii in Xishuangbanna, Yunnan, China. For each species, we excavated intact, fresh, fine roots and measured mechanical and anatomical traits for each branching order. Key Results Mechanical traits varied enormously among the four species within a narrow range of diameters (<2 mm): <0.1-65 MPa for Tr, 4-1135 MPa for Er and 0.4-37 % for εr. Across species, Tr and Er were strongly correlated with stele area ratio, which was also better correlated with topological order than with root diameter, especially at interspecific levels. Conclusions Root topological order plays an important role in explaining variability in fine-root mechanical traits due to its reflection of root tissue development. Accounting for topological order when measuring fine-root traits therefore leads to greater empirical understanding of plant functions (e.g. anchorage) within and across species.
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Affiliation(s)
- Zhun Mao
- AMAP, INRA, CNRS, IRD, CIRAD, University of Montpellier, Montpellier, France
| | - Yan Wang
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, China
| | - M Luke McCormack
- Center of Forest Ecosystem Studies and Qianyanzhou Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research (IGSNRR), Chinese Academy of Sciences (CAS), Beijing, China
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, USA
| | - Nick Rowe
- AMAP, INRA, CNRS, IRD, CIRAD, University of Montpellier, Montpellier, France
| | - Xiaobao Deng
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, China
- Xishuangbanna Station for Tropical Rain Forest Ecosystem Studies, Chinese Ecosystem Research Net, Mengla, Yunnan, China
| | - Xiaodong Yang
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, China
| | - Shangwen Xia
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, China
| | - Jérôme Nespoulous
- AMAP, INRA, CNRS, IRD, CIRAD, University of Montpellier, Montpellier, France
| | - Roy C Sidle
- Sustainability Research Centre, University of the Sunshine Coast, Maroochydore, Queensland, Australia
| | - Dali Guo
- Center of Forest Ecosystem Studies and Qianyanzhou Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research (IGSNRR), Chinese Academy of Sciences (CAS), Beijing, China
| | - Alexia Stokes
- AMAP, INRA, CNRS, IRD, CIRAD, University of Montpellier, Montpellier, France
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Olson ME, Rosell JA, Zamora Muñoz S, Castorena M. Carbon limitation, stem growth rate and the biomechanical cause of Corner's rules. Ann Bot 2018; 122:583-592. [PMID: 29889257 PMCID: PMC6153482 DOI: 10.1093/aob/mcy089] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [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: 01/09/2018] [Accepted: 05/06/2018] [Indexed: 05/29/2023]
Abstract
Background and aims Corner's rules describe a global spectrum from large-leaved plants with thick, sparingly branched twigs with low-density stem tissues and thick piths to plants with thin, highly branched stems with high-density stem tissues and thin piths. The hypothesis was tested that, if similar crown areas fix similar amounts of carbon regardless of leaf size, then large-leaved species, with their distantly spaced leaves, require higher stem growth rates, lower stem tissue densities and stiffnesses, and therefore thicker twigs. Methods Structural equation models were used to test the compatibility of this hypothesis with a dataset on leaf size, shoot tip spacing, stem growth rate and dimensions, and tissue density and mechanics, sampling 55 species drawn from across the angiosperm phylogeny from a morphologically diverse dry tropical community. Key results Very good fit of structural equation models showed that the causal model is highly congruent with the data. Conclusions Given similar amounts of carbon to allocate to stem growth, larger-leaved species require greater leaf spacing and therefore greater stem extension rates and longer stems, in turn requiring lower-density, more flexible, stem tissues than small-leaved species. A given stem can have high resistance to bending because it is thick (has high second moment of area I) or because its tissues are stiff (high Young's modulus E), the so-called E-I trade-off. Because of the E-I trade-off, large-leaved species have fast stem growth rates, low stem tissue density and tissue stiffness, and thick twigs with wide piths and thick bark. The agreement between hypothesis and data in structural equation analyses strongly suggests that Corner's rules emerge as the result of selection favouring the avoidance of self-shading in the context of broadly similar rates of carbon fixation per unit crown area across species.
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Affiliation(s)
- Mark E Olson
- Instituto de Biología, Universidad Nacional Autónoma de México, Tercer Circuito s/n de Ciudad Universitaria, México, Mexico
| | - Julieta A Rosell
- Laboratorio Nacional de Ciencias de la Sostenibilidad, Instituto de Ecología, Universidad Nacional Autónoma de México, Tercer Circuito s/n de Ciudad Universitaria, México, Mexico
| | - Salvador Zamora Muñoz
- Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas, Universidad Nacional Autónoma de México, Circuito Escolar s/n de Ciudad Universitaria, México, Mexico
| | - Matiss Castorena
- Instituto de Biología, Universidad Nacional Autónoma de México, Tercer Circuito s/n de Ciudad Universitaria, México, Mexico
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Imaichi R, Moritoki N, Solvang HK. Evolution of root apical meristem structures in vascular plants: plasmodesmatal networks. Am J Bot 2018; 105:1453-1468. [PMID: 30179250 DOI: 10.1002/ajb2.1153] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [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: 04/03/2018] [Accepted: 06/18/2018] [Indexed: 06/08/2023]
Abstract
PREMISE OF THE STUDY The apical meristem generates indeterminate apical growth of the stem and root of vascular plants. Our previous examination showed that shoot apical meristems (SAMs) can be classified into two types based on plasmodesmatal networks (PNs), which are important elements in symplasmic signaling pathways within the apical meristem. Here, we examined the PNs of root apical meristems (RAMs) in comparison with those of SAMs. METHODS Root apical meristems of 18 families and 22 species of lycophytes and euphyllophytes were analyzed. Plasmodesmata (PD) in cell walls in median longitudinal sections of RAMs were enumerated using transmission electron micrographs, and the PD density per 1 μm2 of each cell wall was calculated. KEY RESULTS Root apical meristems with prominent apical cells of monilophytes (euphyllophytes) and Selaginellaceae (lycophytes) had high PD densities, while RAMs with plural initial cells of gymnosperms and angiosperms (euphyllophytes), and of Lycopodiaceae and Isoetaceae (lycophytes) had low PD densities. This correlation between structures of apical meristems and PD densities is identical to that in SAMs already described. CONCLUSIONS Irrespective of their diversified structures, the RAMs of vascular plants can be classified into two types with respect to PNs: the fern (monilophyte) type, which has a lineage-specific PN with only primary PD, and the seed-plant type, which has an interspecific PN with secondary PD in addition to primary PD. PNs may have played a key role in the evolution of apical meristems in vascular plants.
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Affiliation(s)
- Ryoko Imaichi
- Department of Chemical and Biological Sciences, Japan Women's University, 8-1, Mejirodai 2-chome, Tokyo, 112-8681, Japan
| | - Nobuko Moritoki
- Laboratory of Electron Microscopy, Japan Women's University, 8-1, Mejirodai 2-chome, Tokyo, 112-8681, Japan
| | - Hiroko Kato Solvang
- Marine Mammals Research Group, Institute of Marine Research, P.O. Box 1870 Nordnes, N-5817, Bergen, Norway
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Jud NA, D’Emic MD, Williams SA, Mathews JC, Tremaine KM, Bhattacharya J. A new fossil assemblage shows that large angiosperm trees grew in North America by the Turonian (Late Cretaceous). Sci Adv 2018; 4:eaar8568. [PMID: 30263954 PMCID: PMC6157959 DOI: 10.1126/sciadv.aar8568] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2017] [Accepted: 08/14/2018] [Indexed: 06/08/2023]
Abstract
The diversification of flowering plants and marked turnover in vertebrate faunas during the mid-Cretaceous transformed terrestrial communities, but the transition is obscured by reduced terrestrial deposition attributable to high sea levels. We report a new fossil assemblage from multiple localities in the Upper Cretaceous Ferron Sandstone Member of the Mancos Shale Formation in Utah. The fossils date to the Turonian, a severely underrepresented interval in the terrestrial fossil record of North America. A large silicified log (maximum preserved diameter, 1.8 m; estimated height, ca. 50 m) is assigned to the genus Paraphyllanthoxylon; it is the largest known pre-Campanian angiosperm and the earliest documented occurrence of an angiosperm tree more than 1.0 m in diameter. Foliage and palynomorphs of ferns, conifers, and angiosperms confirm the presence of mixed forest or woodland vegetation. Previously known terrestrial vertebrate remains from the Ferron Sandstone Member include fish teeth, two short dinosaur trackways, and a pterosaur; we report the first turtle and crocodilian remains and an ornithopod sacrum. Previous studies indicate that angiosperm trees were present by the Cenomanian, but this discovery demonstrates that angiosperm trees approaching 2 m in diameter were part of the forest canopies across southern North America by the Turonian (~92 million years ago), nearly 15 million years earlier than previously thought.
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Affiliation(s)
- Nathan A. Jud
- Department of Biology, William Jewell College, Liberty, MO 64068, USA
| | - Michael D. D’Emic
- Department of Biology, Adelphi University, Garden City, NY 11530, USA
- Burpee Museum of Natural History, Rockford, IL 61103, USA
- Department of Anatomical Sciences, Stony Brook University, Stony Brook, NY 11794, USA
| | - Scott A. Williams
- Burpee Museum of Natural History, Rockford, IL 61103, USA
- Museum of the Rockies and Department of Earth Sciences, Montana State University, Bozeman, MT 59717, USA
| | - Josh C. Mathews
- Burpee Museum of Natural History, Rockford, IL 61103, USA
- Department of Biological Sciences, Northern Illinois University, DeKalb, IL 60115, USA
| | - Katie M. Tremaine
- Burpee Museum of Natural History, Rockford, IL 61103, USA
- Museum of the Rockies and Department of Earth Sciences, Montana State University, Bozeman, MT 59717, USA
| | - Janok Bhattacharya
- School of Geography and Earth Sciences, McMaster University, Hamilton, Ontario L8S 4L8, Canada
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Atkinson BA. The critical role of fossils in inferring deep-node phylogenetic relationships and macroevolutionary patterns in Cornales. Am J Bot 2018; 105:1401-1411. [PMID: 29797563 DOI: 10.1002/ajb2.1084] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [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: 09/29/2017] [Accepted: 11/28/2017] [Indexed: 06/08/2023]
Abstract
PREMISE OF THE STUDY The basal asterid order, Cornales, experienced a rapid radiation during the Cretaceous, which has made it difficult to elucidate the early evolution of the order using extant taxa only. Recent paleobotanical studies, however, have begun to shed light on the early diversification of Cornales. Herein, fossils are directly incorporated in phylogenetic and quantitative morphological analyses to reconstruct early cornalean evolution. METHODS A morphological matrix of 77 fruit characters and 58 taxa (24 extinct) was assembled. Parsimony analyses including and excluding fossils were conducted. A fossil inclusive tree was time-scaled to visualize the timing of the initial cornalean radiation. Disparity analyses were utilized to infer the morphological evolution of cornaleans with drupaceous fruits. KEY RESULTS Fossil inclusive and exclusive parsimony analyses resulted in well-resolved deep-node relationships within Cornales. Resolution in the fossil inclusive analysis is substantially higher, revealing a basal grade including Loasaceae, Hydrangeaceae, Hydrostachyaceae, Grubbiaceae, a Hironoia+Amersinia clade, and Curtisiaceae, respectively, that leads to a "core" group containing a clade comprising a Cretaceous grade leading to clade of Nyssaceae, Mastixiaceae, and Davidiaceae that is sister to a Cornaceae+Alangiaceae clade. The time-scaled tree indicates that the initial cornalean diversification occurred before 89.8 Ma. Disparity analyses suggest the morphological diversity of Cornales peaked during the Paleogene. CONCLUSIONS Phylogenetic analyses clearly demonstrate that novel character mosaics of Cretaceous cornaleans play a critical role in resolving deep-node relationships within Cornales. The post-Cretaceous increase of cornalean disparity is associated with a shift in morphospace occupation, which can be explained from ecological and developmental perspectives.
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Affiliation(s)
- Brian A Atkinson
- Department of Ecology and Evolutionary Biology and Biodiversity Institute, University of Kansas, Lawrence, KS, 66045, USA
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Abstract
The seed habit represents a remarkable evolutionary advance in plant sexual reproduction. Since the Paleozoic, seeds carry a seed coat that protects, nourishes and facilitates the dispersal of the fertilization product(s). The seed coat architecture evolved to adapt to different environments and reproductive strategies in part by modifying its thickness. Here, we review the great natural diversity observed in seed coat thickness among angiosperms and its molecular regulation in Arabidopsis.
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Affiliation(s)
- Olivier Coen
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, Route de St-Cyr (RD10), 78026, Versailles Cedex, France
- Ecole Doctorale 567 Sciences du Végétal, University Paris-Sud, University of Paris-Saclay, bat 360, 91405, Orsay Cedex, France
| | - Enrico Magnani
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, Route de St-Cyr (RD10), 78026, Versailles Cedex, France.
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40
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Blackman CJ, Gleason SM, Cook AM, Chang Y, Laws CA, Westoby M. The links between leaf hydraulic vulnerability to drought and key aspects of leaf venation and xylem anatomy among 26 Australian woody angiosperms from contrasting climates. Ann Bot 2018; 122:59-67. [PMID: 29668853 PMCID: PMC6025239 DOI: 10.1093/aob/mcy051] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [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: 12/12/2017] [Accepted: 03/18/2018] [Indexed: 05/13/2023]
Abstract
Background and Aims The structural properties of leaf venation and xylem anatomy strongly influence leaf hydraulics, including the ability of leaves to maintain hydraulic function during drought. Here we examined the strength of the links between different leaf venation traits and leaf hydraulic vulnerability to drought (expressed as P50leaf by rehydration kinetics) in a diverse group of 26 woody angiosperm species, representing a wide range of leaf vulnerabilities, from four low-nutrient sites with contrasting rainfall across eastern Australia. Methods For each species we measured key aspects of leaf venation design, xylem anatomy and leaf morphology. We also assessed for the first time the scaling relationships between hydraulically weighted vessel wall thickness (th) and lumen breadth (bh) across vein orders and habitats. Key Results Across species, variation in P50leaf was strongly correlated with the ratio of vessel wall thickness (th) to lumen breadth (bh) [(t/b)h; an index of conduit reinforcement] at each leaf vein order. Concomitantly, the scaling relationship between th and bh was similar across vein orders, with a log-log slope less than 1 indicating greater xylem reinforcement in smaller vessels. In contrast, P50leaf was not related to th and bh individually, to major vein density (Dvmajor) or to leaf size. Principal components analysis revealed two largely orthogonal trait groupings linked to variation in leaf size and drought tolerance. Conclusions Our results indicate that xylem conduit reinforcement occurs throughout leaf venation, and remains closely linked to leaf drought tolerance irrespective of leaf size.
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Affiliation(s)
- Chris J Blackman
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Sean M Gleason
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
- USDA-ARS, Water Management and Systems Research Unit, Fort Collins, CO, USA
| | - Alicia M Cook
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
| | - Yvonne Chang
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
| | - Claire A Laws
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
| | - Mark Westoby
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
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Gleason SM, Blackman CJ, Gleason ST, McCulloh KA, Ocheltree TW, Westoby M. Vessel scaling in evergreen angiosperm leaves conforms with Murray's law and area-filling assumptions: implications for plant size, leaf size and cold tolerance. New Phytol 2018; 218:1360-1370. [PMID: 29603233 DOI: 10.1111/nph.15116] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 02/15/2018] [Indexed: 05/26/2023]
Abstract
Water transport in leaf vasculature is a fundamental process affecting plant growth, ecological interactions and ecosystem productivity, yet the architecture of leaf vascular networks is poorly understood. Although Murray's law and the West-Brown-Enquist (WBE) theories predict convergent scaling of conduit width and number, it is not known how conduit scaling is affected by habitat aridity or temperature. We measured the scaling of leaf size, conduit width and conduit number within the leaves of 36 evergreen Angiosperms spanning a large range in aridity and temperature in eastern Australia. Scaling of conduit width and number in midribs and 2° veins did not differ across species and habitats (P > 0.786), and did not differ from that predicted by Murray's law (P = 0.151). Leaf size was strongly correlated with the hydraulic radius of petiole conduits (r2 = 0.83, P < 0.001) and did not differ among habitats (P > 0.064), nor did the scaling exponent differ significantly from that predicted by hydraulic theory (P = 0.086). The maximum radius of conduits in petioles was positively correlated with the temperature of the coldest quarter (r2 = 0.67; P < 0.001), suggesting that habitat temperature restricts the occurrence of wide-conduit species in cold habitats.
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Affiliation(s)
- Sean M Gleason
- Water Management and Systems Research Unit, United States Department of Agriculture, Agricultural Research Service, Fort Collins, CO, 80526, USA
- Department of Forest and Rangeland Stewardship, Colorado State University, Fort Collins, CO, 80523, USA
- Department of Biological Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Chris J Blackman
- Department of Biological Sciences, Macquarie University, Sydney, NSW, 2109, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - Scott T Gleason
- University Corporation for Atmospheric Research (UCAR), 3300 Mitchell Lane, Boulder, CO, 80301, USA
| | - Katherine A McCulloh
- Department of Botany, University of Wisconsin - Madison, Madison, WI, 53706, USA
| | - Troy W Ocheltree
- Department of Forest and Rangeland Stewardship, Colorado State University, Fort Collins, CO, 80523, USA
| | - Mark Westoby
- Department of Biological Sciences, Macquarie University, Sydney, NSW, 2109, Australia
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Reeves G, Singh P, Rossberg TA, Sogbohossou EOD, Schranz ME, Hibberd JM. Natural Variation within a Species for Traits Underpinning C 4 Photosynthesis. Plant Physiol 2018; 177:504-512. [PMID: 29678862 PMCID: PMC6001323 DOI: 10.1104/pp.18.00168] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 03/30/2018] [Indexed: 05/20/2023]
Abstract
Engineering C4 photosynthesis into C3 crops could substantially increase their yield by alleviating photorespiratory losses. This objective is challenging because the C4 pathway involves complex modifications to the biochemistry, cell biology, and anatomy of leaves. Forward genetics has provided limited insight into the mechanistic basis of these properties, and there have been no reports of significant quantitative intraspecific variation of C4 attributes that would allow trait mapping. Here, we show that accessions of the C4 species Gynandropsis gynandra collected from locations across Africa and Asia exhibit natural variation in key characteristics of C4 photosynthesis. Variable traits include bundle sheath size and vein density, gas-exchange parameters, and carbon isotope discrimination associated with the C4 state. The abundance of transcripts encoding core enzymes of the C4 cycle also showed significant variation. Traits relating to water use showed more quantitative variation than those associated with carbon assimilation. We propose that variation in these traits likely adapted the hydraulic system for increased water use efficiency rather than improving carbon fixation, indicating that selection pressure may drive C4 diversity in G. gynandra by modifying water use rather than photosynthesis. The accessions analyzed can be easily crossed and produce fertile offspring. Our findings, therefore, indicate that natural variation within this C4 species is sufficiently large to allow genetic mapping of key C4 traits and regulators.
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Affiliation(s)
- Gregory Reeves
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom
| | - Pallavi Singh
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom
| | - Timo A Rossberg
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom
| | - E O Deedi Sogbohossou
- Biosystematics Group, Department of Plant Sciences, Wageningen University, Wageningen 6700 AA, The Netherlands
| | - M Eric Schranz
- Biosystematics Group, Department of Plant Sciences, Wageningen University, Wageningen 6700 AA, The Netherlands
| | - Julian M Hibberd
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom
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Tobe H, Huang YL, Kadokawa T, Tamura MN. Floral structure and development in Nartheciaceae (Dioscoreales), with special reference to ovary position and septal nectaries. J Plant Res 2018; 131:411-428. [PMID: 29569170 DOI: 10.1007/s10265-018-1026-9] [Citation(s) in RCA: 3] [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: 12/07/2017] [Accepted: 02/26/2018] [Indexed: 06/08/2023]
Abstract
We present a comparative study of the floral structure and development of Nartheciaceae, a small dioscorealean family consisting of five genera (Aletris, Lophiola, Metanarthecium, Narthecium, and Nietneria). A noticeable diversity existed in nine floral characters. Analyses of their respective character states in the light of a phylogenetic context revealed that the flowers of Nartheciaceae, whose plesiomorphies occur in Aletris and Metanarthecium, have evolved toward in all or part of Lophiola, Narthecium, and Nietneria: (1) loss of a perianth tube; (2) stamen insertion at the perianth base; (3) congenital carpel fusion; (4) loss of the septal nectaries; (5) unilocular style; (6) unfused lateral carpellary margins in the style; (7) flower with the median outer tepal on the abaxial side; (8) flower with moniliform hairs; and (9) flower with weak monosymmetry. We further found that, as the flowers developed, the ovary shifted its position from inferior to superior. As a whole, their structure changes suggest that the Nartheciaceae flowers have evolved in close association with pollination and seed dispersal. By considering inferior ovaries and the presence of septal nectaries as plesiomorphies of Nartheciaceae, we discussed evolution of the ovary position and septal nectaries in all the monocots.
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Affiliation(s)
- Hiroshi Tobe
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan.
| | - Yu-Ling Huang
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan
- National Museum of Natural Science, Guancian Rd., Taichung, 404, Taiwan
| | - Tomoki Kadokawa
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan
| | - Minoru N Tamura
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan
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Abstract
The climbing habit has evolved multiple times during the evolutionary history of angiosperms. Plants evolved various strategies for climbing, such as twining stems, tendrils and hooks. Tendrils are threadlike organs with the ability to twine around other structures through helical growth; they may be derived from a variety of structures, such as branches, leaflets and inflorescences. The genetic capacity to grow as a tendrilled climber existed in some of the earliest land plants; however, the underlying molecular basis of tendril development has been studied in only a few taxa. Here, we summarize what is known about the molecular basis of tendril development in model and candidate model species from key tendrilled families, that is, Fabaceae, Vitaceae, Cucurbitaceae, Passifloraceae and Bignoniaceae. Studies on tendril molecular genetics and development show the molecular basis of tendril formation and ontogenesis is diverse, even when tendrils have the same ontogenetic origin, for example leaflet-derived tendrils in Fabaceae and Bignoniaceae. Interestingly, all tendrils perform helical growth during contact-induced coiling, indicating that such ability is not correlated with their ontogenetic origin or phylogenetic history. Whether the same genetic networks are involved during helical growth in diverse tendrils still remains to be investigated.
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Affiliation(s)
- Mariane S Sousa-Baena
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, São Paulo, SP, 05508-090, Brazil
- Department of Plant Biology, University of California, Davis, CA, 95616, USA
| | - Lúcia G Lohmann
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, São Paulo, SP, 05508-090, Brazil
| | - José Hernandes-Lopes
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, São Paulo, SP, 05508-090, Brazil
| | - Neelima R Sinha
- Department of Plant Biology, University of California, Davis, CA, 95616, USA
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Callens C, Tucker MR, Zhang D, Wilson ZA. Dissecting the role of MADS-box genes in monocot floral development and diversity. J Exp Bot 2018; 69:2435-2459. [PMID: 29718461 DOI: 10.1093/jxb/ery086] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 03/16/2018] [Indexed: 05/05/2023]
Abstract
Many monocot plants have high social and economic value. These include grasses such as rice (Oryza sativa), wheat (Triticum aestivum), and barley (Hordeum vulgare), which produce soft commodities for many food and beverage industries, and ornamental flowers such ase lily (Lilium longiflorum) and orchid (Oncidium Gower Ramsey), which represent an important component of international flower markets. There is constant pressure to improve the development and diversity of these species, with a significant emphasis on flower development, and this is particularly relevant considering the impact of changing environments on reproduction and thus yield. MADS-box proteins are a family of transcription factors that contain a conserved 60 amino acid MADS-box motif. In plants, attention has been devoted to characterization of this family due to their roles in inflorescence and flower development, which holds promise for the modification of floral architecture for plant breeding. This has been explored in diverse angiosperms, but particularly the dicot model Arabidopsis thaliana. The focus of this review is on the less well characterized roles of the MADS-box proteins in monocot flower development and how changes in MADS-box proteins throughout evolution may have contributed to creating a diverse range of flowers. Examining these changes within the monocots can identify the importance of certain genes and pinpoint those which might be useful in future crop improvement and breeding strategies.
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Affiliation(s)
- Cindy Callens
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire, UK
- School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Urrbrae, SA, Australia
| | - Matthew R Tucker
- School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Urrbrae, SA, Australia
| | - Dabing Zhang
- School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Urrbrae, SA, Australia
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Zoe A Wilson
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire, UK
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Mochizuki K, Kawakita A. Pollination by fungus gnats and associated floral characteristics in five families of the Japanese flora. Ann Bot 2018; 121:651-663. [PMID: 29300811 PMCID: PMC5853022 DOI: 10.1093/aob/mcx196] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [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: 11/06/2017] [Accepted: 12/13/2017] [Indexed: 05/09/2023]
Abstract
BACKGROUND AND AIMS Pollination by fungus gnats (Mycetophilidae and Sciaridae) is uncommon, but is nevertheless known to occur in 20 genera among eight angiosperm families. Because many fungus gnat-pollinated plants possess a dark red floral display, we hypothesized that fungus gnat pollination is more widespread among plants with similar floral display than currently known. We thus studied the pollination biology of flowers with dark red pigmentation in five families, focusing particularly on plants having small, flat, actinomorphic flowers with exposed nectaries and short stamens, because these floral characteristics mirror those of a known fungus gnat-pollinated genus (Mitella). METHODS We observed daytime and night-time floral visitors for a total of 194.5 h in Aucuba japonica (Garryaceae), Euonymus spp. (Celastraceae), Disanthus cercidifolius (Hamamelidaceae), Micranthes fusca (Saxifragaceae) and Streptopus streptopoides (Liliaceae). Visitors were categorized into functional groups, and a pollination importance index (PII) was calculated for each functional group based on visitation frequency, pollen load and behaviour on flowers. KEY RESULTS Fungus gnats were dominant among the 1762 insects observed (36-92 % depending on the plant species) and were the most important pollinators among all plants studied (PII: 0.529-1). Fungus gnat visits occurred during the daytime and, more frequently, at dusk. Most often, pollen grains became clumped on the ventral side of the head and/or thorax as the short-proboscid fungus gnats foraged on nectar and came into contact with anthers located close to the flower base. CONCLUSIONS Pollination by fungus gnats is probably more common than previously thought, especially in habitats similar to those of the plants studied (moist forest understorey, streamside or subalpine meadow) where fungus gnats are abundant year-round. Our results further suggest that there may be a previously unnoticed association between fungus gnat pollination and dark red coloration, and a shared overall floral architecture among the plants studied.
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Affiliation(s)
- Ko Mochizuki
- Center for Ecological Research, Kyoto University, Otsu, Shiga, Japan
- For correspondence. E-mail:
| | - Atsushi Kawakita
- Center for Ecological Research, Kyoto University, Otsu, Shiga, Japan
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Jud NA, Gandolfo MA, Iglesias A, Wilf P. Fossil flowers from the early Palaeocene of Patagonia, Argentina, with affinity to Schizomerieae (Cunoniaceae). Ann Bot 2018; 121:431-442. [PMID: 29309506 PMCID: PMC5838809 DOI: 10.1093/aob/mcx173] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 11/09/2017] [Indexed: 06/01/2023]
Abstract
Background and Aims Early Palaeocene (Danian) plant fossils from Patagonia provide information on the recovery from the end-Cretaceous extinction and Cenozoic floristic change in South America. Actinomorphic flowers with eight to ten perianth parts are described and evaluated in a phylogenetic framework. The goal of this study is to determine the identity of these fossil flowers and to discuss their evolutionary, palaeoecological and biogeographical significance. Methods More than 100 fossilized flowers were collected from three localities in the Danian Salamanca and Peñas Coloradas Formations in southern Chubut. They were prepared, photographed and compared with similar extant and fossil flowers using published literature and herbarium specimens. Phylogenetic analysis was performed using morphological and molecular data. Key results The fossil flowers share some but not all the synapomorphies that characterize the Schizomerieae, a tribe within Cunoniaceae. These features include the shallow floral cup, variable number of perianth parts arranged in two whorls, laciniate petals, anthers with a connective extension, and a superior ovary with free styles. The number of perianth parts is doubled and the in situ pollen is tricolporate, with a surface more like that of other Cunoniaceae outside Schizomerieae, such as Davidsonia or Weinmannia. Conclusions An extinct genus of crown-group Cunoniaceae is recognized and placed along the stem lineage leading to Schizomerieae. Extant relatives are typical of tropical to southern-temperate rainforests, and these fossils likely indicate a similarly warm and wet temperate palaeoclimate. The oldest reliable occurrences of the family are fossil pollen and wood from the Upper Cretaceous of the Antarctica and Argentina, whereas in Australia the family first occurs in upper Palaeocene deposits. This discovery demonstrates that the family survived the Cretaceous-Palaeogene boundary event in Patagonia and that diversification of extant lineages in the family was under way by the earliest Cenozoic.
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Affiliation(s)
- Nathan A Jud
- L. H. Bailey Hortorium, Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, USA
| | - Maria A Gandolfo
- L. H. Bailey Hortorium, Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, USA
| | - Ari Iglesias
- Universidad Nacional del Comahue, Instituto de Investigaciones en Biodiversidad y Ambiente INIBIOMA-CONICET, San Carlos de Bariloche, Rio Negro, Argentina
| | - Peter Wilf
- Department of Geosciences, Pennsylvania State University, University Park, PA, USA
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48
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Stull GW, Schori M, Soltis DE, Soltis PS. Character evolution and missing (morphological) data across Asteridae. Am J Bot 2018; 105:470-479. [PMID: 29656519 DOI: 10.1002/ajb2.1050] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [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: 07/11/2017] [Accepted: 12/08/2017] [Indexed: 06/08/2023]
Abstract
PREMISE OF THE STUDY Our current understanding of flowering plant phylogeny provides an excellent framework for exploring various aspects of character evolution through comparative analyses. However, attempts to synthesize this phylogenetic framework with extensive morphological data sets have been surprisingly rare. Here, we explore character evolution in Asteridae (asterids), a major angiosperm clade, using an extensive morphological data set and a well-resolved phylogeny. METHODS We scored 15 phenotypic characters (spanning chemistry, vegetative anatomy, and floral, fruit, and seed features) across 248 species for ancestral state reconstruction using a phylogenetic framework based on 73 plastid genes and the same 248 species. KEY RESULTS Iridoid production, unitegmic ovules, and cellular endosperm were all reconstructed as synapomorphic for Asteridae. Sympetaly, long associated with asterids, shows complex patterns of evolution, suggesting it arose several times independently within the clade. Stamens equal in number to the petals is likely a synapomorphy for Gentianidae, a major asterid subclade. Members of Lamianae, a major gentianid subclade, are potentially diagnosed by adnate stamens, unilacunar nodes, and simple perforation plates. CONCLUSIONS The analyses presented here provide a greatly improved understanding of character evolution across Asteridae, highlighting multiple characters potentially synapomorphic for major clades. However, several important parts of the asterid tree are poorly known for several key phenotypic features (e.g., degree of petal fusion, integument number, nucellus type, endosperm type, iridoid production). Further morphological, anatomical, developmental, and chemical investigations of these poorly known asterids are critical for a more detailed understanding of early asterid evolution.
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Affiliation(s)
- Gregory W Stull
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Melanie Schori
- United States Department of Agriculture, National Germplasm Resources Laboratory, Beltsville, MD, 20705-2305, USA
| | - Douglas E Soltis
- Department of Biology, University of Florida, Gainesville, FL, 32611-8525, USA
- Florida Museum of Natural History, University of Florida, Gainesville, FL, 32611-7800, USA
| | - Pamela S Soltis
- Florida Museum of Natural History, University of Florida, Gainesville, FL, 32611-7800, USA
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Suetsugu K. Independent recruitment of a novel seed dispersal system by camel crickets in achlorophyllous plants. New Phytol 2018; 217:828-835. [PMID: 29120037 DOI: 10.1111/nph.14859] [Citation(s) in RCA: 8] [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] [Received: 09/14/2017] [Accepted: 09/23/2017] [Indexed: 05/26/2023]
Abstract
The seeds of most heterotrophic plants, commonly referred to as dust seeds, are typically dispersed in the air like dust particles. Therefore, little attention has been paid to how seeds of heterotrophic plants are dispersed, owing to the notion that wind dispersal is the dominant strategy. However, inconspicuous but fleshy, indehiscent fruit can be observed in distantly related plants that have independently evolved full heterotrophy. Here I investigated the seed dispersal system in three unrelated fully heterotrophic plants with fleshy, indehiscent fruits (Yoania amagiensis, Monotropastrum humile and Phacellanthus tubiflorus) by direct observation, a differential exclusion experiment of fruit feeders and investigation on seed viability through the digestive tract. The present study revealed that camel crickets are the major seed disperser in three achlorophyllous plants in the study population. This represents the first evidence of seed dispersal by camel crickets in any angiosperm species. These heterotrophic plants grow in the understorey of densely vegetated forests where wind is probably an ineffective seed dispersal agent. Life-history traits of the achlorophyllous plants associated with heterotrophic lifestyles, such as colonization of dark understorey habitats and dust seeds, could facilitate independent recruitment of the novel endozoochorous seed dispersal system by camel crickets.
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Affiliation(s)
- Kenji Suetsugu
- Department of Biology, Graduate School of Science, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, 657-8501, Japan
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50
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Morris H, Gillingham MAF, Plavcová L, Gleason SM, Olson ME, Coomes DA, Fichtler E, Klepsch MM, Martínez-Cabrera HI, McGlinn DJ, Wheeler EA, Zheng J, Ziemińska K, Jansen S. Vessel diameter is related to amount and spatial arrangement of axial parenchyma in woody angiosperms. Plant Cell Environ 2018; 41:245-260. [PMID: 29047119 DOI: 10.1111/pce.13091] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [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: 07/27/2017] [Revised: 09/22/2017] [Accepted: 09/28/2017] [Indexed: 05/13/2023]
Abstract
Parenchyma represents a critically important living tissue in the sapwood of the secondary xylem of woody angiosperms. Considering various interactions between parenchyma and water transporting vessels, we hypothesize a structure-function relationship between both cell types. Through a generalized additive mixed model approach based on 2,332 woody angiosperm species derived from the literature, we explored the relationship between the proportion and spatial distribution of ray and axial parenchyma and vessel size, while controlling for maximum plant height and a range of climatic factors. When factoring in maximum plant height, we found that with increasing mean annual temperatures, mean vessel diameter showed a positive correlation with axial parenchyma proportion and arrangement, but not for ray parenchyma. Species with a high axial parenchyma tissue fraction tend to have wide vessels, with most of the parenchyma packed around vessels, whereas species with small diameter vessels show a reduced amount of axial parenchyma that is not directly connected to vessels. This finding provides evidence for independent functions of axial parenchyma and ray parenchyma in large vesselled species and further supports a strong role for axial parenchyma in long-distance xylem water transport.
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Affiliation(s)
- Hugh Morris
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
- Laboratory for Applied Wood Materials, Empa-Swiss Federal Laboratories for Materials Testing and Research, St. Gallen, 9014, Switzerland
| | - Mark A F Gillingham
- Institute of Evolutionary Ecology and Conservation Genomics, Ulm University, Albert-Einstein-Allee 11, D-89069, Ulm, Germany
| | - Lenka Plavcová
- Department of Biology, Faculty of Science, University of Hradec Králové, Rokitanského 62, 500 03, Hradec Králové, Czech Republic
| | - Sean M Gleason
- USDA-ARS Water Management and Systems Research Unit, Fort Collins, CO, 80526, USA
| | - Mark E Olson
- Instituto de Biología, Universidad Nacional Autónoma de México, Tercer Circuito s/n de CU, Mexico, DF, 04510, Mexico
| | - David A Coomes
- Forest Ecology and Conservation Group, Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EA, UK
| | - Esther Fichtler
- Department of Crop Sciences, Tropical Plant Production and Agricultural Systems Modelling, Göttingen University, Grisebachstrasse 6, 37077, Göttingen, Germany
| | - Matthias M Klepsch
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | | | - Daniel J McGlinn
- Department of Biology, College of Charleston, Charleston, SC, 29424, USA
| | - Elisabeth A Wheeler
- Department of Forest Biomaterials, NC State University, Raleigh, NC, 27695-8005, USA
- North Carolina Museum of Natural Sciences, 11 West Jones St., Raleigh, NC, 27601, USA
| | - Jingming Zheng
- Zheng JingminG, College of Forestry, Beijing Forestry University, Beijing, 100083, China
| | - Kasia Ziemińska
- Arnold Arboretum of Harvard University, 1300 Centre St, Boston, MA, 02130, USA
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
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