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Sevilleno SS, An HR, Cabahug-Braza RAM, Ahn YJ, Hwang YJ. Cytogenetic Study and Pollen Viability of Phalaenopsis Queen Beer 'Mantefon'. PLANTS (BASEL, SWITZERLAND) 2023; 12:2828. [PMID: 37570982 PMCID: PMC10421358 DOI: 10.3390/plants12152828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 07/14/2023] [Accepted: 07/29/2023] [Indexed: 08/13/2023]
Abstract
Intergeneric and interspecific hybridization has been employed for the breeding of Phalaenopsis to transfer desirable traits between species, producing novel phenotypes with improved size, color, form, and flower-bearing ability. These characteristics are often enhanced; however, many of these hybrids are triploids and have reduced or complete sterility, for example, Phalaenopsis Queen Beer 'Mantefon', an important novelty-type cultivar in Asia, particularly in China, Japan, and Republic of Korea. Despite the increasing demand for the crop for ornamental purposes, little is known about its cytogenetics, which is essential for breeding and, consequently, crop improvement. In this study, karyotyping using fluorescence in situ hybridization, meiotic chromosome behavior analysis, pollen staining, and in vitro viability germination tests were performed to understand the cause of hybrid sterility and pollen abnormality in Phalaenopsis Queen Beer 'Mantefon' from a cytogenetic perspective. Viability tests revealed pollen infertility at all flower developmental stages, confirmed by the absence of pollen tube growth. Aberrant chromosomal behavior was observed in pollen mother cells (PMCs), frequently forming univalents, chromosomal bridges, and laggards during the entire meiotic process. PMCs were also divided irregularly into sporads with varying numbers of micronuclei, which may be responsible for pollen sterility in this cultivar. Altogether, the cytogenetic analyses provided insights into the pollen development of Phalaenopsis Queen Beer 'Mantefon' and the conceivable causes of its infertility.
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Affiliation(s)
| | - Hye Ryun An
- Floriculture Research Division, National Institute of Horticultural & Herbal Science, Rural Development Administration, Wanju 55365, Republic of Korea;
| | | | - Yun-Jae Ahn
- Department of Horticultural Science, Kyungpook National University, Daegu 41566, Republic of Korea;
| | - Yoon-Jung Hwang
- Department of Convergence Science, Sahmyook University, Seoul 01795, Republic of Korea;
- Plant Genetics and Breeding Institute, Sahmyook University, Seoul 01795, Republic of Korea;
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Lanzino M, Palermo AM, Pellegrino G. The effect of inflorescence display size and flower position on pollination success in two deceptive and one rewarding orchid. PLANT BIOLOGY (STUTTGART, GERMANY) 2023; 25:396-402. [PMID: 36719068 DOI: 10.1111/plb.13505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 01/17/2023] [Indexed: 06/18/2023]
Abstract
Inflorescence display size and flower position on the inflorescence play important roles in plant reproduction, in the formation of fruits and are primarily linked to pollinator behaviour. We used three orchids to determine how visitation rates and choice of pollinator depend on number and position of the flowers along the inflorescence. We measured reproductive success in (1) natural conditions, (2) hand-pollination experiments and (3) an experimental design, by modifying composition of inflorescences in populations of two deceptive orchids, Orchis anthropophora and O. italica, and one rewarding orchid, Anacamptis coriophora subsp. fragrans. There were no differences in natural fruit production in relation to flower position on the inflorescence (i.e. upper versus lower part), suggesting no preference of pollinators for different parts of the inflorescence. Hand-pollination experiments highlighted low pollen limitation in A. coriophora subsp. fragrans but high limitation in O. italica and O. anthropophora. Reproductive success of deceptive orchids in experimental plots decreased significantly when flowers on the upper half of the inflorescence were removed leading to reduced floral display, while reproductive success of the nectariferous species did not differ significantly. Our data highlight that in the examined orchids there is no clear relationship between fruit formation and flower position along inflorescences. Thus we can affirm that, for orchids, the entire inflorescence plays a dominant role in insect attraction but the part of the flower spike does not influence the choice of the insect. This implies that all flowers have the same possibility of receiving visits from pollinators, and therefore each flower has the same opportunity to set fruit.
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Affiliation(s)
- M Lanzino
- Department of Biology, Ecology and Earth Sciences, University of Calabria, Cosenza, Italy
| | - A M Palermo
- Department of Biology, Ecology and Earth Sciences, University of Calabria, Cosenza, Italy
| | - G Pellegrino
- Department of Biology, Ecology and Earth Sciences, University of Calabria, Cosenza, Italy
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Lanzino M, Palermo AM, Pellegrino G. Pollinaria Reconfiguration Mechanism of Widespread Euro-Mediterranean Orchids: The Effects of Increasing Air Temperature. PLANTS (BASEL, SWITZERLAND) 2022; 11:1327. [PMID: 35631751 PMCID: PMC9145125 DOI: 10.3390/plants11101327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 05/12/2022] [Accepted: 05/16/2022] [Indexed: 06/15/2023]
Abstract
Orchids are fascinating for many reasons: their reproductive strategies, their pollination systems and the various morphological adaptations they have evolved, including the presence of pollen grains agglomerated into two masses, called pollinia, which form a structure known as a pollinarium. After withdrawal from a flower, the pollinarium undergoes a bending movement such that the pollen masses become correctly orientated to strike the stigma. We evaluated the duration of pollinator visits to inflorescences and the effects of temperature on pollinaria reconfiguration in eight orchid species in order to analyze the effects of increasing air temperature on the changes in bending time, and thus on geitonogamy levels. The impact of temperature on insect behavior was not assessed because our priority was to understand the effects of temperature on the process of pollinaria reconfiguration. All the examined species showed natural reconfiguration times that were 1.7-3.0 times longer than the pollinator residency times. A higher temperature showed a reduction in bending time regardless of the species tested. However, the bending time was never shorter than the residence time of the insects on the flower. Our data showed that high temperatures had a limited effect on the pollinarium reconfiguration time, thus indicating that high temperatures had a limited effect on folding compared to the effect that it had on the viability of the pollen.
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Affiliation(s)
- Micaela Lanzino
- Department of Biology, Ecology and Earth Sciences, University of Calabria, 87036 Rende, Italy
| | - Anna Maria Palermo
- Department of Biology, Ecology and Earth Sciences, University of Calabria, 87036 Rende, Italy
| | - Giuseppe Pellegrino
- Department of Biology, Ecology and Earth Sciences, University of Calabria, 87036 Rende, Italy
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Bersweden L, Viruel J, Schatz B, Harland J, Gargiulo R, Cowan RS, Calevo J, Juan A, Clarkson JJ, Leitch AR, Fay MF. Microsatellites and petal morphology reveal new patterns of admixture in Orchis hybrid zones. AMERICAN JOURNAL OF BOTANY 2021; 108:1388-1404. [PMID: 34418070 DOI: 10.1002/ajb2.1710] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 02/20/2021] [Accepted: 02/23/2021] [Indexed: 05/23/2023]
Abstract
PREMISE The genetic structure of hybrid zones provides insight into the potential for gene flow to occur between plant taxa. Four closely related European orchid species (Orchis anthropophora, O. militaris, O. purpurea, and O. simia) hybridize when they co-occur. We aimed to characterize patterns of hybridization in O. militaris-O. purpurea, O. purpurea-O. simia, and O. anthropophora-O. simia hybrid zones using molecular and morphological data. METHODS We used 11 newly isolated nuclear microsatellites to genotype 695 individuals collected from seven hybrid zones and six allopatric parental populations in France. Geometric morphometric analysis was conducted using 15 labellum landmarks to capture the main aspects of petal shape. RESULTS Backcrossing was asymmetric toward O. militaris in multiple O. militaris-O. purpurea hybrid zones. Hybrids in O. purpurea-O. simia and O. anthropophora-O. simia hybrid zones were largely limited to F1 and F2 generations, but further admixture had occurred. These patterns were reflected in labellum geometric morphometric data, which correlated strongly with nuclear microsatellite data in all three species combinations. CONCLUSIONS The coexistence of parental and admixed individuals in these Orchis hybrid zones implies they are likely to be tension zones being maintained by a balance between gene flow into the hybrid zone and selection acting against admixed individuals. The pattern of admixture in the three species combinations suggests intrinsic selection acting on the hybrids is weaker in more closely related taxa.
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Affiliation(s)
- Leif Bersweden
- Jodrell Laboratory, Royal Botanic Gardens, Kew TW9 3DS, UK
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK
| | - Juan Viruel
- Jodrell Laboratory, Royal Botanic Gardens, Kew TW9 3DS, UK
| | - Bertrand Schatz
- Centre for Ecology and Evolution, University of Montpellier, Montpellier 34090, France
| | - Joanna Harland
- Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | | | - Robyn S Cowan
- Jodrell Laboratory, Royal Botanic Gardens, Kew TW9 3DS, UK
| | - Jacopo Calevo
- Department of Life Sciences and Systems Biology, University of Turin, Turin 10125, Italy
| | - Ana Juan
- Department of Environmental Sciences & Natural Resources, University of Alicante, San Vicente, Alicante 03690, Spain
| | | | - Andrew R Leitch
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK
| | - Michael F Fay
- Jodrell Laboratory, Royal Botanic Gardens, Kew TW9 3DS, UK
- School of Plant Biology, University of Western Australia, Crawley, WA 6009, Australia
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Pellegrino G, Mahmoudi M, Palermo AM. Pollen viability of Euro-Mediterranean orchids under different storage conditions: The possible effects of climate change. PLANT BIOLOGY (STUTTGART, GERMANY) 2021; 23:140-147. [PMID: 32967048 DOI: 10.1111/plb.13185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Accepted: 08/24/2020] [Indexed: 06/11/2023]
Abstract
The future impact of climate change and a warmer world is a matter of great concern. We therefore aimed to evaluate the effects of temperature on pollen viability and fruit set of Mediterranean orchids. The in vitro and controlled pollination experiments were performed to evaluate the ability of pollinia stored at lower and higher temperatures to germinate and produce fruits and seeds containing viable embryos. In all of the examined orchids, pollen stored at -20 °C remained fully viable for up to 3 years, reducing its percentage germination from year 4 onwards. Pollinia stored at higher temperatures had a drastic reduction in vitality after 2 days at 41-44 °C, while pollinia stored at 47-50 °C did not show any pollen tube growth. The different levels of pollen viability duration among the examined orchids can be related to their peculiar reproductive biology and pollination ecology. The germinability of pollinia stored at lower temperatures for long periods suggests that orchid pollinia can be conserved ex situ. In contrast, higher temperatures can have harmful effects on the vitality of pollen and consequently on reproductive success of the plants. To our knowledge, this is the first report demonstrating the effects of global change on orchid pollen, and on pollen ability to tolerate, or not, higher air temperatures. Although vegetative reproduction allows orchids to survive a few consecutive warm years, higher temperatures for several consecutive years can have dramatic effects on reproductive success of orchids.
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Affiliation(s)
- G Pellegrino
- Department of Biology, Ecology and Earth Sciences (DiBEST), University of Calabria, Rende, CS, Italy
| | - M Mahmoudi
- Faculté des Sciences de Tunis, Université de Tunis El-Manar, Tunis, Tunisia
- Laboratoire des écosystèmes pastoraux et valorisation des plantes spontanées et des micro-organismes associés, Institut des Régions Arides, Médenine, Tunisia
| | - A M Palermo
- Department of Biology, Ecology and Earth Sciences (DiBEST), University of Calabria, Rende, CS, Italy
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Custodio CC, Machado-Neto NB, Singer RB, Pritchard HW, Seaton PT, Marks TR. Storage of orchid pollinia with varying lipid thermal fingerprints. PROTOPLASMA 2020; 257:1401-1413. [PMID: 32506243 DOI: 10.1007/s00709-020-01514-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 05/12/2020] [Indexed: 06/11/2023]
Abstract
Orchid pollinia have the potential to make a valuable contribution to current techniques of germplasm storage and assisted reproduction, yet information regarding their preservation and their ability to remain viable over time is currently limited. Dactylorhiza fuchsii and Disa uniflora were used as models for investigating potential techniques for storing orchid pollinia. Initially, freshly harvested pollinia of Dact. fuchsii were incubated at 25 °C and 100% RH (relative humidity) for up to 7 days and germinated in vitro. For pollinia from both species, moisture sorption isotherms were constructed and thermal fingerprints generated using differential scanning calorimetry (DSC). Pollinia were stored at three temperatures (5, - 18 and - 196 °C) after equilibration at four different RHs (5, 33, 50 and 75%) and germinated. The isotherms and DSC results varied between species. Compared with D. uniflora, pollinia of Dact. fuchsii consistently equilibrated at higher moisture content (MC) for each RH, had less detectable lipids by DSC and had shorter lifespans, remaining viable after 3-4 months only at - 20 and - 196 °C and at low RH (5 and 33%). Both species' pollinia stored well at - 20 °C and - 196 °C, although there was some evidence of a small loss of viability under cryopreservation. In conclusion, pollen of these two species can be stored successfully for at least 3-4 months, and to maximize the pre-storage quality, it is recommended that fresh pollen is collected from flowers just prior to anthesis.
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Affiliation(s)
- Ceci Castilho Custodio
- Agronomy College, UNOESTE, Rodovia Raposo Tavares, km 572, Presidente Prudente, São Paulo, 19067-175, Brazil
| | - Nelson B Machado-Neto
- Agronomy College, UNOESTE, Rodovia Raposo Tavares, km 572, Presidente Prudente, São Paulo, 19067-175, Brazil.
| | - Rodrigo B Singer
- Departamento Botânica, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Hugh W Pritchard
- Department of Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, Wakehurst Place, Ardingly, West Sussex, RH17 6TN, UK
| | - Philip T Seaton
- Department of Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, Wakehurst Place, Ardingly, West Sussex, RH17 6TN, UK
| | - Timothy R Marks
- Department of Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, Wakehurst Place, Ardingly, West Sussex, RH17 6TN, UK
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Zhang J, Zhang D, Wei J, Shi X, Ding H, Qiu S, Guo J, Li D, Zhu K, Horvath DP, Xia Y. Annual growth cycle observation, hybridization and forcing culture for improving the ornamental application of Paeonia lactiflora Pall. in the low-latitude regions. PLoS One 2019; 14:e0218164. [PMID: 31194806 PMCID: PMC6564672 DOI: 10.1371/journal.pone.0218164] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 05/28/2019] [Indexed: 11/19/2022] Open
Abstract
Expanding the southern range of herbaceous peony (Paeonia lactiflora Pall.) is a meaningful and worthwhile horticultural endeavor in the Northern Hemisphere. However, high temperatures in winter seriously hinder the bud dormancy release and flowering of peony in the more southern areas of subtropical and tropical regions. Resource introduction and hybridization can contribute to creating new cultivars with high adaptability in a warmer winter climate. In this study, three representative cultivars of P. lactiflora were screened for flowering capabilities and their annual growth cycles were observed to provide information needed for hybridization. Among these three cultivars, ‘Hang Baishao’ is the best adapted cultivar for southern growing regions and is unique in its ability to thrive in southern areas of N 30°00’. Pollen viability of ‘Hang Baishao’ was 55.60% based on five measuring methods, which makes it an excellent male parent in hybridization. Hybrid plants among these three cultivars grew well, but all of their flower buds aborted. Additionally, the ability of three growth regulators that advance the flowering of ‘Hang Baishao’ to promote an indoor cultivation strategy for improving peony application as a potted or cut-flower plant was tested. 5-azacytidine could impact the growth of ‘Hang Baishao’ and induce dwarfism and small flowers but not advance the flowering time. Gibberellin A3 promoted the sprouting and growth significantly, but all plants eventually withered. Chilling at 0–4°C for four weeks and irrigation with 300 mg/L humic acid was the optimal combination used to hasten flowering and ensure flowering quality simultaneously. These results can lay the foundation for future studies on the chilling requirement trait, bud dormancy release and key functional gene exploration of herbaceous peony. Additionally, this study can also provide guidance for expanding the range of economically important plants with the winter dormancy trait to the low-latitude regions.
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Affiliation(s)
- Jiaping Zhang
- Physiology and Molecular Biology Laboratory of Ornamental Plants, Institute of Landscape Architecture, College of Agriculture & Biotechnology, Zhejiang University, Hangzhou, Zhejiang Province, China
| | - Dong Zhang
- Physiology and Molecular Biology Laboratory of Ornamental Plants, Institute of Landscape Architecture, College of Agriculture & Biotechnology, Zhejiang University, Hangzhou, Zhejiang Province, China
| | - Jianfen Wei
- Research & Development Center, Hangzhou Landscaping Incorporated, Hangzhou, Zhejiang Province, China
| | - Xiaohua Shi
- Research & Development Centre of Flower, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang Province, China
| | - Huaqiao Ding
- Research & Development Centre of Flower, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang Province, China
| | - Shuai Qiu
- Research & Development Center, Hangzhou Landscaping Incorporated, Hangzhou, Zhejiang Province, China
| | - Juan Guo
- Research & Development Center, Hangzhou Landscaping Incorporated, Hangzhou, Zhejiang Province, China
| | - Danqin Li
- Physiology and Molecular Biology Laboratory of Ornamental Plants, Institute of Landscape Architecture, College of Agriculture & Biotechnology, Zhejiang University, Hangzhou, Zhejiang Province, China
| | - Kaiyuan Zhu
- Research & Development Centre of Flower, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang Province, China
| | - David P. Horvath
- Sunflower and Plant Biology Research, Red River Valley Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture, Fargo, North Dakota, United States of America
- * E-mail: (YX); (DH)
| | - Yiping Xia
- Physiology and Molecular Biology Laboratory of Ornamental Plants, Institute of Landscape Architecture, College of Agriculture & Biotechnology, Zhejiang University, Hangzhou, Zhejiang Province, China
- * E-mail: (YX); (DH)
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Yuan SC, Chin SW, Lee CY, Chen FC. Phalaenopsis pollinia storage at sub-zero temperature and its pollen viability assessment. BOTANICAL STUDIES 2018; 59:1. [PMID: 29299696 PMCID: PMC5752644 DOI: 10.1186/s40529-017-0218-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 12/26/2017] [Indexed: 06/06/2023]
Abstract
BACKGROUND In a breeding program, usually only superior parents are chosen for cross hybridization. Pollens of elite cultivars may not be available at hand. Properly stored pollens provide an opportunity for cross hybridization at unavailable time. RESULTS Pollen of a Phalaenopsis hybrid was evaluated for the storage ability at different temperatures, including room temperature, 4, - 20, and - 80 °C for up to 96 weeks. The viability of pollen was assessed by TTC staining, in vitro germination and hand pollination during and after storage. Pollen stored at all temperatures for 4 weeks remained viable and capable of successful pollination. Pollen lost its viability after 4 weeks at room temperature. Pollen remains viable after 40 weeks at 4 °C, and after 96 weeks at both - 20 and - 80 °C of storage. Viable pollen could be successfully pollinated to the female parent at all effective storage conditions and produced seeds. CONCLUSIONS Our results indicate that Phalaenopsis pollen can be stored at 4 °C up to 40 weeks for short-term purpose. For long-term storage, pollen can be kept at both - 20 and -80 °C.
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Affiliation(s)
- Shih-Chang Yuan
- Department of Plant Industry, National Pingtung University of Science & Technology, Pingtung, 91201 Taiwan
| | - Shih-Wen Chin
- Department of Plant Industry, National Pingtung University of Science & Technology, Pingtung, 91201 Taiwan
| | - Chen-Yu Lee
- Department of Plant Industry, National Pingtung University of Science & Technology, Pingtung, 91201 Taiwan
| | - Fure-Chyi Chen
- Department of Plant Industry, National Pingtung University of Science & Technology, Pingtung, 91201 Taiwan
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Wang Z, Wang Y, Kohalmi SE, Amyot L, Hannoufa A. SQUAMOSA PROMOTER BINDING PROTEIN-LIKE 2 controls floral organ development and plant fertility by activating ASYMMETRIC LEAVES 2 in Arabidopsis thaliana. PLANT MOLECULAR BIOLOGY 2016; 92:661-674. [PMID: 27605094 DOI: 10.1007/s11103-016-0536-x] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 08/26/2016] [Indexed: 05/09/2023]
Abstract
A network of genes is coordinately expressed to ensure proper development of floral organs and fruits, which are essential for generating new offspring in flowering plants. In Arabidopsis thaliana, microRNA156 (miR156) plays a role in regulating the development of flowers and siliques by targeting members of the SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) gene family. Despite the important roles of the miR156/SPL network, our understanding of its downstream genes that are involved in floral organ and silique growth is still incomplete. Here, we report that the miR156/SPL2 regulatory pathway regulates pollen production, fertility rate, and the elongation of floral organs, including petals, sepals, and siliques in Arabidopsis. Transgenic plants exhibiting both overexpression of miR156 and dominant-negative alleles of SPL2 had reduced ASYMMETRIC LEAVES 2 (AS2) transcript levels in their siliques. Furthermore, their fertility phenotype was similar to that of the AS2 loss-of-function mutant. We also demonstrate that the SPL2 protein binds to the 5'UTR of the AS2 gene in vivo, indicating that AS2 is directly regulated by SPL2. Our results suggest that the miR156/SPL2 pathway affects floral organs, silique development and plant fertility, as well as directly regulates AS2 expression.
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Affiliation(s)
- Zhishuo Wang
- Agriculture and Agri-Food Canada, 1391 Sandford Street, London, ON, N5V 4T3, Canada
- Department of Biology, University of Western Ontario, 1511 Richmond Street, London, ON, N6A 5B7, Canada
| | - Ying Wang
- Agriculture and Agri-Food Canada, 1391 Sandford Street, London, ON, N5V 4T3, Canada
- Department of Biology, University of Western Ontario, 1511 Richmond Street, London, ON, N6A 5B7, Canada
- Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada
| | - Susanne E Kohalmi
- Department of Biology, University of Western Ontario, 1511 Richmond Street, London, ON, N6A 5B7, Canada
| | - Lisa Amyot
- Agriculture and Agri-Food Canada, 1391 Sandford Street, London, ON, N5V 4T3, Canada
| | - Abdelali Hannoufa
- Agriculture and Agri-Food Canada, 1391 Sandford Street, London, ON, N5V 4T3, Canada.
- Department of Biology, University of Western Ontario, 1511 Richmond Street, London, ON, N6A 5B7, Canada.
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10
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Hobbhahn N, Johnson SD, Harder LD. The mating consequences of rewarding vs. deceptive pollination systems: Is there a quantity-quality trade-off? ECOL MONOGR 2016. [DOI: 10.1002/ecm.1235] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Nina Hobbhahn
- School of Life Sciences; University of KwaZulu-Natal; Pietermaritzburg 3201 South Africa
- Department of Biological Sciences; University of Calgary; Calgary Alberta T2N 1N4 Canada
| | - Steven D. Johnson
- School of Life Sciences; University of KwaZulu-Natal; Pietermaritzburg 3201 South Africa
| | - Lawrence D. Harder
- Department of Biological Sciences; University of Calgary; Calgary Alberta T2N 1N4 Canada
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11
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Luca A, Palermo AM, Bellusci F, Pellegrino G. Pollen competition between two sympatric Orchis species (Orchidaceae): the overtaking of conspecific of heterospecific pollen as a reproductive barrier. PLANT BIOLOGY (STUTTGART, GERMANY) 2015; 17:219-225. [PMID: 24889383 DOI: 10.1111/plb.12199] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 03/26/2014] [Indexed: 06/03/2023]
Abstract
The frequency of hybrid formation in angiosperms depends on how and when heterospecific pollen is transferred to the stigma, and on the success of that heterospecific pollen at fertilising ovules. We applied pollen mixtures to stigmas to determine how pollen interactions affect siring success and the frequency of hybrid formation between two species of Mediterranean deceptive orchid. Plants of Orchis italica and O. anthropophora were pollinated with conspecific and heterospecific pollen (first conspecific pollen then heterospecific pollen and vice versa) and molecular analysis was used to check the paternity of the seeds produced. In this pair of Mediterranean orchids, competition between conspecific and heterospecific pollen functions as a post-pollination pre-zygotic barrier limiting the frequency of the formation of hybrids in nature. Flowers pollinated with heterospecific pollen can remain receptive for the arrival of conspecific pollen for a long time. There is always an advantage of conspecific pollen for fruit formation, whether it comes before or after heterospecific pollen, because it overtakes the heterospecific pollen. The conspecific pollen advantage exhibited in O. italica and O. anthropophora is likely to result from the reduced germination of heterospecific pollen or retarded growth of heterospecific pollen tubes in the stigma and ovary. Overall, the results indicate that our hybrid zone represents a phenomenon of little evolutionary consequence, and the conspecific pollen advantage maintains the genetic integrity of the parental species.
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Affiliation(s)
- A Luca
- Department of Biology, Ecology and Earth Sciences, University of Calabria, Rende, Italy
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12
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Marks TR, Seaton PT, Pritchard HW. Desiccation tolerance, longevity and seed-siring ability of entomophilous pollen from UK native orchid species. ANNALS OF BOTANY 2014; 114:561-9. [PMID: 25006180 PMCID: PMC4204667 DOI: 10.1093/aob/mcu139] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
BACKGROUND AND AIMS Pollinator-limited seed-set in some terrestrial orchids is compensated for by the presence of long-lived flowers. This study tests the hypothesis that pollen from these insect-pollinated orchids should be desiccation tolerant and relatively long lived using four closely related UK terrestrial species; Anacamptis morio, Dactylorhiza fuchsii, D. maculata and Orchis mascula. METHODS Pollen from the four species was harvested from inflorescences and germinated in vitro, both immediately and also after drying to simulate interflower transit. Their tolerance to desiccation and short-term survival was additionally assessed after 3 d equilibration at a range of relative humidities (RHs), and related to constructed sorption isotherms (RH vs. moisture content, MC). Ageing of D. fuchsii pollen was further tested over 2 months against temperature and RH, and the resultant survival curves were subjected to probit analysis, and the distribution of pollen death in time (σ) was determined. The viability and siring ability, following artificial pollinations, were determined in D. fuchsii pollen following storage for 6 years at -20 °C. KEY RESULTS The pollen from all four species exhibited systematic increases in germinability and desiccation tolerance as anthesis approached, and pollen from open flowers generally retained high germinability. Short-term storage revealed sensitivity to low RH, whilst optimum survival occurred at comparable RHs in all species. Similarly, estimated pollen life spans (σ) at differing temperatures were longest under the dry conditions. Despite a reduction in germination and seeds per capsule, long-term storage of D. fuchsii pollen did not impact on subsequent seed germination in vitro. CONCLUSIONS Substantial pollen desiccation tolerance and life span of the four entomophilous orchids reflects a resilient survival strategy in response to unpredictable pollinator visitation, and presents an alternative approach to germplasm conservation.
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Affiliation(s)
- Timothy R Marks
- Seed Conservation Department, Royal Botanic Gardens, Kew, Wakehurst Place, Ardingly, West Sussex RH17 6TN, UK
| | - Philip T Seaton
- Seed Conservation Department, Royal Botanic Gardens, Kew, Wakehurst Place, Ardingly, West Sussex RH17 6TN, UK
| | - Hugh W Pritchard
- Seed Conservation Department, Royal Botanic Gardens, Kew, Wakehurst Place, Ardingly, West Sussex RH17 6TN, UK
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