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Wan X, Sun D, Gao C. Flower opening dynamics, pollen-ovule ratio, stigma receptivity and stigmatic pollen germination (in-vivo) in Chaenomeles speciosa (Sweet) Nakai. Sci Rep 2024; 14:7127. [PMID: 38531911 DOI: 10.1038/s41598-024-57655-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 03/20/2024] [Indexed: 03/28/2024] Open
Abstract
Although Chaenomeles is widely used in horticulture, traditional Chinese medicine and landscape greening, insufficient research has hindered its breeding and seed selection. This study investigated the floral phenology, floral organ characteristics, palynology, and breeding systems of Chaenomeles speciosa (Sweet) Nakai. The floral characteristics of C. speciosa were observed both visually and stereoscopically. The microstructures of the flower organs were observed using scanning electron microscopy. Pollen stainability was determined using triphenyl tetrazolium chloride staining. Stigma receptivity was determined using the benzidine-H2O2 method and the post-artificial pollination pollen germination method. The breeding system was assessed based on the outcrossing index and pollen-ovule ratio. The flowers of C. speciosa were bisexual with a flowering period from March to April. The flowering periods of single flowers ranged from 8 to 19 d, and those of single plants lasted 18-20 d. The anthers were cylindrical, with the base attached to the filament, and were split longitudinally to release pollen. The flower had five styles, with a connate base. The ovaries had five carpels and five compartments. The inverted ovules were arranged in two rows on the placental axis. The stigma of C. speciosa was dry and had many papillary protrusions. In the early flowering stage (1-2 d of flowering), the pollen exhibited high stainability (up to 84.24%), but all stainability was lost at 7 d of flowering. Storage at - 20 °C effectively delayed pollen inactivation. The stigma receptivity of C. speciosa lasted for approximately 7 days, and the breeding system was classified as outcrossing with partial self-compatibility.
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Affiliation(s)
- Xianqin Wan
- Institute for Forest Resources and Environment of Guizhou, Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou Province, College of Forestry, Guizhou University, Jiaxiu South Road, Guiyang, 550025, China
| | - Dongchan Sun
- Institute for Forest Resources and Environment of Guizhou, Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou Province, College of Forestry, Guizhou University, Jiaxiu South Road, Guiyang, 550025, China
| | - Chao Gao
- Institute for Forest Resources and Environment of Guizhou, Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou Province, College of Forestry, Guizhou University, Jiaxiu South Road, Guiyang, 550025, China.
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Valdés-Florido A, Tan L, Maguilla E, Simón-Porcar VI, Zhou YH, Arroyo J, Escudero M. Drivers of diversification in Linum (Linaceae) by means of chromosome evolution: correlations with biogeography, breeding system and habit. Ann Bot 2023; 132:949-962. [PMID: 37738171 PMCID: PMC10808019 DOI: 10.1093/aob/mcad139] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 09/18/2023] [Indexed: 09/24/2023]
Abstract
BACKGROUND AND AIMS Chromosome evolution leads to hybrid dysfunction and recombination patterns and has thus been proposed as a major driver of diversification in all branches of the tree of life, including flowering plants. In this study we used the genus Linum (flax species) to evaluate the effects of chromosomal evolution on diversification rates and on traits that are important for sexual reproduction. Linum is a useful study group because it has considerable reproductive polymorphism (heterostyly) and chromosomal variation (n = 6-36) and a complex pattern of biogeographical distribution. METHODS We tested several traditional hypotheses of chromosomal evolution. We analysed changes in chromosome number across the phylogenetic tree (ChromEvol model) in combination with diversification rates (ChromoSSE model), biogeographical distribution, heterostyly and habit (ChromePlus model). KEY RESULTS Chromosome number evolved across the Linum phylogeny from an estimated ancestral chromosome number of n = 9. While there were few apparent incidences of cladogenesis through chromosome evolution, we inferred up to five chromosomal speciation events. Chromosome evolution was not related to heterostyly but did show significant relationships with habit and geographical range. Polyploidy was negatively correlated with perennial habit, as expected from the relative commonness of perennial woodiness and absence of perennial clonality in the genus. The colonization of new areas was linked to genome rearrangements (polyploidy and dysploidy), which could be associated with speciation events during the colonization process. CONCLUSIONS Chromosome evolution is a key trait in some clades of the Linum phylogeny. Chromosome evolution directly impacts speciation and indirectly influences biogeographical processes and important plant traits.
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Affiliation(s)
- Ana Valdés-Florido
- Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, Avenida Reina Mercedes no. 6, 41012, Seville, Spain
| | - Lu Tan
- Panxi Crops Research and Utilization Key Laboratory of Sichuan Province, Xichang University, Xichang, Sichuan, 615000, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Enrique Maguilla
- Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, Avenida Reina Mercedes no. 6, 41012, Seville, Spain
- Área de Botánica, Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, Ctra de Utrera km 1 sn, 41013, Seville, Spain
| | - Violeta I Simón-Porcar
- Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, Avenida Reina Mercedes no. 6, 41012, Seville, Spain
| | - Yong-Hong Zhou
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Juan Arroyo
- Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, Avenida Reina Mercedes no. 6, 41012, Seville, Spain
| | - Marcial Escudero
- Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, Avenida Reina Mercedes no. 6, 41012, Seville, Spain
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Lanzino M, Palermo AM, Pellegrino G. Pollination mechanism in Serapias with no pollinaria reconfiguration. AoB Plants 2023; 15:plad054. [PMID: 37899971 PMCID: PMC10601389 DOI: 10.1093/aobpla/plad054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 08/09/2023] [Indexed: 10/31/2023]
Abstract
Orchidaceae, one of the most numerous families in the world's flora, have evolved various pollination strategies to favour cross-pollination, such as deceptive pollination and pollinarium reconfiguration. Among the terrestrial orchids of the Mediterranean, only species belonging to the genus Serapias show a strategy defined as shelter imitation. The floral elements form a tubular structure that insects use during their resting phases. The purpose of this article was to clarify the mechanisms that guarantee pollination with particular attention to the morphological interactions between orchids and pollinators and whether pollinaria reconfiguration is necessary in the promotion of cross-pollination in Serapias. Breeding system experiments and hand-pollination treatments indicated that Serapias was highly self-compatible, shows low value of natural fruit set and is pollinator limited. Time-lapse photos showed that the pollinarium had no refolding of the stipe or caudicle after its removal from the flower. The morphology of the flower determined the attack of the pollinarium on the occiput/vertex of insect. When the insect left the flower, the pollinarium was unable to encounter the stigma. When the insect made a second visit to another flower, the pollen masses of the first pollinarium ended up on the stigma and at the same time, the insect picked up a second pollinarium. Our observations and analyses suggested that morphological interactions between flower and pollinator are crucial to the success of pollination and to prevent self-pollination and thus that pollinarium reconfiguration is unnecessary in shelter deceptive orchids, such as Serapias species, for the promotion of cross-pollination. Serapias represent a case of interactions between plant and pollinator; the formation of the tubular shape of the flower is an essential preadaptation for the development of resting site mimicry originating exclusively in Serapias among Mediterranean orchids.
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Affiliation(s)
- Micaela Lanzino
- Department of Biology, Ecology and Earth Sciences, University of Calabria, 87036 Rende, Cosenza, Italy
| | - Anna Maria Palermo
- Department of Biology, Ecology and Earth Sciences, University of Calabria, 87036 Rende, Cosenza, Italy
| | - Giuseppe Pellegrino
- Department of Biology, Ecology and Earth Sciences, University of Calabria, 87036 Rende, Cosenza, Italy
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Wang X, Hu D, Chen Y, Xiang M, Tang H, Yi Y, Tang X. Ancillary polymorphic floral traits between two morphs adaptive to hawkmoth pollination in distylous plant Tirpitzia sinensis (Linaceae). BMC Plant Biol 2022; 22:273. [PMID: 35655126 PMCID: PMC9164504 DOI: 10.1186/s12870-022-03659-w] [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] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 05/24/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Floral morphs are characterized differentiations in reciprocal positions of sexual organs and ancillary floral traits in heterostylous plants. However, it remains unclear how differential floral morphs ensure reproductive success between morphs using the same pollinator. RESULTS Measurements of floral traits in white-flowered Tirpitzia sinensis with long corolla tubes indicated that it is typically distylous, long-styled (L-) morph producing more but smaller pollen grains per flower than short-styled (S-) morph. Both morphs secreted more nectar volume at night than in the day and the sugar composition was rich in sucrose, potentially adaptive to pollination by hawkmoths (Macroglossum spp.) which were active at dusk. A bumblebee species functioned as the nectar robber in both morphs and a honeybee as the pollen feeder in the S-morph. The L-morph secreted more nectar volume but relatively lower sucrose/hexose ratio than the S-morph. Floral visitation rate by hawkmoths was higher but its pollination efficiency was lower in the S-morph than the L-morph. Hand pollination treatments indicated self-incompatibility in T. sinensis and seed set of open-pollinated flowers did not differ between morphs. CONCLUSIONS Our findings suggest that the two morphs differ with respect to traits relevant to pollination. The L-morph, with its exserted stigma, has more pollen grains per anther and a greater volume of nectar, which may prolong the foraging time and increase the pollination efficiency of hawkmoths. The S-morph has a higher sucrose/hexose ratio in its nectar which can be more attractive to hawkmoths and increase the visit rates. Ancillary polymorphic floral traits between two morphs are adaptive to hawkmoth and ensure reproductive success in distylous plant T. sinensis.
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Affiliation(s)
- Xiaoyue Wang
- Key Laboratory of State Forestry Administration On Biodiversity Conservation in Karst Mountainous Areas of Southwestern China, Guizhou Normal University, Guiyang, 550025, China
- School of Life Sciences, Guizhou Normal University, Guiyang, 550025, China
| | - Demei Hu
- Key Laboratory of State Forestry Administration On Biodiversity Conservation in Karst Mountainous Areas of Southwestern China, Guizhou Normal University, Guiyang, 550025, China
- School of Life Sciences, Guizhou Normal University, Guiyang, 550025, China
| | - Yan Chen
- Key Laboratory of State Forestry Administration On Biodiversity Conservation in Karst Mountainous Areas of Southwestern China, Guizhou Normal University, Guiyang, 550025, China
- School of Life Sciences, Guizhou Normal University, Guiyang, 550025, China
| | - Mengda Xiang
- Key Laboratory of State Forestry Administration On Biodiversity Conservation in Karst Mountainous Areas of Southwestern China, Guizhou Normal University, Guiyang, 550025, China
- School of Life Sciences, Guizhou Normal University, Guiyang, 550025, China
| | - Hanqing Tang
- Key Laboratory of State Forestry Administration On Biodiversity Conservation in Karst Mountainous Areas of Southwestern China, Guizhou Normal University, Guiyang, 550025, China
- School of Life Sciences, Guizhou Normal University, Guiyang, 550025, China
| | - Yin Yi
- Key Laboratory of State Forestry Administration On Biodiversity Conservation in Karst Mountainous Areas of Southwestern China, Guizhou Normal University, Guiyang, 550025, China
| | - Xiaoxin Tang
- Key Laboratory of State Forestry Administration On Biodiversity Conservation in Karst Mountainous Areas of Southwestern China, Guizhou Normal University, Guiyang, 550025, China.
- School of Life Sciences, Guizhou Normal University, Guiyang, 550025, China.
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Trueman SJ, Kämper W, Nichols J, Ogbourne SM, Hawkes D, Peters T, Hosseini Bai S, Wallace HM. Pollen limitation and xenia effects in a cultivated mass-flowering tree, Macadamia integrifolia (Proteaceae). Ann Bot 2022; 129:135-146. [PMID: 34473241 PMCID: PMC8796667 DOI: 10.1093/aob/mcab112] [Citation(s) in RCA: 2] [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: 06/06/2021] [Accepted: 09/01/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND AND AIMS Pollen limitation is most prevalent among bee-pollinated plants, self-incompatible plants and tropical plants. However, we have very little understanding of the extent to which pollen limitation affects fruit set in mass-flowering trees despite tree crops accounting for at least 600 million tons of the 9200 million tons of annual global food production. METHODS We determined the extent of pollen limitation in a bee-pollinated, partially self-incompatible, subtropical tree by hand cross-pollinating the majority of flowers on mass-flowering macadamia (Macadamia integrifolia) trees that produce about 200 000-400 000 flowers. We measured tree yield and kernel quality and estimated final fruit set. We genotyped individual kernels by MassARRAY to determine levels of outcrossing in orchards and assess paternity effects on nut quality. KEY RESULTS Macadamia trees were pollen-limited. Supplementary cross-pollination increased nut-in-shell yield, kernel yield and fruit set by as much as 97, 109 and 92 %, respectively. The extent of pollen limitation depended upon the proximity of experimental trees to trees of another cultivar because macadamia trees were highly outcrossing. Between 84 and 100 % of fruit arose from cross-pollination, even at 200 m (25 rows) from orchard blocks of another cultivar. Large variations in nut-in-shell mass, kernel mass, kernel recovery and kernel oil concentration were related to differences in fruit paternity, including between self-pollinated and cross-pollinated fruit, thus demonstrating pollen-parent effects on fruit quality (i.e. xenia). CONCLUSIONS This study is the first to demonstrate pollen limitation in a mass-flowering tree. Improved pollination led to increased kernel yield of 0.31-0.59 tons ha-1, which equates currently to higher farm-gate income of approximately $US3720-$US7080 ha-1. The heavy reliance of macadamia flowers on cross-pollination and the strong xenia effects on kernel mass demonstrate the high value that pollination services can provide to food production.
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Affiliation(s)
- Stephen J Trueman
- Centre for Planetary Health and Food Security, School of Environment and
Science, Griffith University, Nathan, QLD 4111,
Australia
| | - Wiebke Kämper
- Centre for Planetary Health and Food Security, School of Environment and
Science, Griffith University, Nathan, QLD 4111,
Australia
- Department of Animal Ecology, Evolution and Biodiversity, Ruhr-University
Bochum, 44780 Bochum, Germany
| | - Joel Nichols
- Centre for Planetary Health and Food Security, School of Environment and
Science, Griffith University, Nathan, QLD 4111,
Australia
| | - Steven M Ogbourne
- GeneCology Research Centre, University of the Sunshine Coast,
Maroochydore DC, QLD 4558, Australia
- School of Science, Technology & Engineering, University of the Sunshine
Coast, Maroochydore DC, QLD 4558, Australia
| | - David Hawkes
- Australian Genome Research Facility, Gehrmann Laboratories, University of
Queensland, Brisbane, QLD 4072, Australia
| | - Trent Peters
- Australian Genome Research Facility, Gehrmann Laboratories, University of
Queensland, Brisbane, QLD 4072, Australia
| | - Shahla Hosseini Bai
- Centre for Planetary Health and Food Security, School of Environment and
Science, Griffith University, Nathan, QLD 4111,
Australia
| | - Helen M Wallace
- Centre for Planetary Health and Food Security, School of Environment and
Science, Griffith University, Nathan, QLD 4111,
Australia
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Watanabe K, Shimizu A, Sugawara T. Polygamous breeding system identified in the distylous genus Psychotria: P. manillensis in the Ryukyu archipelago, Japan. PeerJ 2021; 9:e12318. [PMID: 34824905 PMCID: PMC8590391 DOI: 10.7717/peerj.12318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 09/25/2021] [Indexed: 11/20/2022] Open
Abstract
Distyly is a genetic polymorphism composed of long-and short-styled flowers in a population. The evolutionary breakdown of distyly has been reported in many taxa, and mainly involves a shift toward monomorphism or dioecism. However, a shift toward monoecism has not been reported in distylous species. Psychotria (Rubiaceae), one of the world largest genera, consists of distylous species and their derivatives. In our preliminary study, however, we identified some monoecious individuals in a population of Psychotria manillensis. To understand the breeding system and reproductive biology of P. manillensis, we investigated floral traits, open fruit set, and flower visitors, and performed hand pollination and bagging experiments in five populations of Okinawa and Iriomote islands, Ryukyu Islands, Japan. The populations of P. manillensis were composed mainly of monoecious individuals (54%), followed by female (30%), male (14%), and hermaphroditic (2%) individuals at the time of flower collection. Of the collected flowers, 93% were functionally unisexual (male or female), whereas only 6.5% were perfect (hermaphroditic). However, some individuals changed sex mainly towards increasing femaleness during the flowering period. Moreover, 35% of the studied plants changed their sexual expression over the years. P. manillensis showed self-compatibility and no agamospermy. The fruit set under open pollination varied among populations and years (1.8–21.9%), but it was significantly higher than that of auto-selfing (0.68–1.56%). Wasps and flies were the main flower visitors and probably the main pollinators of the species. In conclusion, P. manillensis was revealed to be polygamous, involving monoecious, female, male, and hermaphroditic individuals. This is the first report of the polygamous breeding system not only in the genus Psychotria, but also in all heterostylous taxa.
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Affiliation(s)
- Kenta Watanabe
- National Institute of Technology, Okinawa College, Henoko, Nago, Okinawa, Japan
| | - Akira Shimizu
- Department of Biological Sciences, School of Science, Tokyo Metropolitan University, Minami-Ohsawa, Hachioji, Tokyo, Japan.,Research Institute of Evolutionary Biology, Inc., Setagaya-ku, Tokyo, Japan.,University Museum, the University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Takashi Sugawara
- Department of Botany, National Museum of Nature and Science, Amakubo, Tsukuba, Ibaraki, Japan
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Wang D, Yu H, Chen G. Scent chemistry and pollinators in the holoparasitic plant Cynomorium songaricum (Cynomoriaceae). Plant Biol (Stuttg) 2021; 23:111-120. [PMID: 32915486 DOI: 10.1111/plb.13180] [Citation(s) in RCA: 2] [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: 01/30/2020] [Accepted: 08/27/2020] [Indexed: 06/11/2023]
Abstract
Holoparasitic plants are interesting heterotrophic angiosperms. However, carrion- or faeces-mimicking is rarely described for such plants. There is no information on the pollination biology of Cynomoriaceae, despite the fact that these plants are rare and vulnerable. This is the first study to reveal pollination in a member of this family, Cynomorium songaricum, a root holoparasite with a distinctive and putrid floral odour. From 2016 to 2018, we studied the floral volatiles, floral visitors and pollinators, behavioural responses of visitors to floral volatiles, breeding system, flowering phenology and floral biology of two wild populations of C. songaricum in Alxa, Inner Mongolia, China. A total of 42 volatiles were identified in inflorescences of C. songaricum. Among these volatiles are compounds known as typical carrion scents, such as p-cresol, indole, dimethyl disulphide and 1-octen-3-ol. C. songaricum is pollinated by various Diptera, such as Musca domestica, M. stabulans (Muscidae), Delia setigera, D. platura (Anthomyiidae), Lucilia sericata, L. caesar (Calliphoridae), Wohlfahrtia indigens, Sarcophaga noverca, S. crassipalpis and Sarcophila meridionalis (Sarcophagidae). The inflorescence scent of C. songaricum attracted these pollinators. The plants significantly benefit from insect pollination, although wind can be a pollen vector in the absence of pollinators. C. songaricum is a cross-pollinated, self-incompatible plant. Our findings suggest that C. songaricum releases malodorous volatiles to attract Diptera to achieve pollination. This new example lays the foundation for further comparative studies in other members of this plant group and contributes to a better understanding of fly-pollinated, carrion mimicking plants.
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Affiliation(s)
- D Wang
- Key Laboratory of Forage and Endemic Crop Biotechnology, Ministry of Education, School of Life Science, The Good Agriculture Practice Engineering Technology Research Center of Chinese and Mongolian Medicine, Inner Mongolia University, Hohhot, 010070, China
| | - H Yu
- Key Laboratory of Forage and Endemic Crop Biotechnology, Ministry of Education, School of Life Science, The Good Agriculture Practice Engineering Technology Research Center of Chinese and Mongolian Medicine, Inner Mongolia University, Hohhot, 010070, China
| | - G Chen
- Key Laboratory of Forage and Endemic Crop Biotechnology, Ministry of Education, School of Life Science, The Good Agriculture Practice Engineering Technology Research Center of Chinese and Mongolian Medicine, Inner Mongolia University, Hohhot, 010070, China
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Balducci MG, Van der Niet T, Johnson SD. Diel scent and nectar rhythms of an African orchid in relation to bimodal activity patterns of hawkmoth pollinators. Ann Bot 2020; 126:1155-1164. [PMID: 32674148 PMCID: PMC7684705 DOI: 10.1093/aob/mcaa132] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [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: 05/20/2020] [Accepted: 07/13/2020] [Indexed: 05/26/2023]
Abstract
BACKGROUND AND AIMS The temporal dimensions of floral adaptation to pollinators are not yet well understood, partly because we lack accurate information on the diel rhythms of flower visitation for many pollinators. We investigated whether diel patterns of pollinator visitation to flowers of the African woodland orchid Bonatea polypodantha are synchronized with rhythms of floral anthesis, scent emission and nectar availability. METHODS Direct observations and motion-activated cameras were used to identify pollinators of B. polypodantha and to document their activity periods. The timing of pollinaria removal from flowers, emission of scent and availability of nectar was also measured. RESULTS We found that B. polypodantha is pollinated exclusively by short-tongued hawkmoths. Pollinaria of the orchid are affixed between the labial palps of the moths and brush over the protruding stigmatic arms. The flowers also receive visits by long-tongued hawkmoths, but these act as nectar thieves. Tracking of pollinaria removal from flowers confirmed that pollination occurs only at night. Camera footage revealed a striking crepuscular pattern of foraging by short-tongued hawkmoths with peaks of activity during the twilight periods at dusk and at dawn. In contrast, long-tongued hawkmoths were found to visit flowers throughout the night. Flowers of B. polypodantha exhibit unimodal peaks of anthesis, scent emission (dominated by nitrogenous aromatics) and nectar availability before or around dusk. CONCLUSIONS Flowers of B. polypodantha are pollinated exclusively by short-tongued hawkmoths, which show crepuscular foraging activity at dusk and dawn. Floral phenophases of the orchid are closely synchronized with the peak of pollinator activity at dusk.
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Affiliation(s)
- Marco G Balducci
- Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal, Scottsville, South Africa
| | - Timotheüs Van der Niet
- Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal, Scottsville, South Africa
| | - Steven D Johnson
- Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal, Scottsville, South Africa
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Coetzee A, Spottiswoode CN, Seymour CL. Post-pollination barriers enable coexistence of pollinator-sharing ornithophilous Erica species. J Plant Res 2020; 133:873-881. [PMID: 32997284 DOI: 10.1007/s10265-020-01226-8] [Citation(s) in RCA: 4] [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: 06/06/2020] [Accepted: 09/23/2020] [Indexed: 06/11/2023]
Abstract
Some evolutionary radiations produce a number of closely-related species that continue to coexist. In such plant systems, when pre-pollination barriers are weak, relatively strong post-pollination reproductive barriers are required to maintain species boundaries. Even when post-pollination barriers are in place, however, reproductive interference and pollinator dependence may strengthen selection for pre-pollination barriers. We assessed whether coexistence of species from the unusually speciose Erica genus in the fynbos biome, South Africa, is enabled through pre-pollination or post-pollination barriers. We also tested for reproductive interference and pollinator dependence. We investigated this in natural populations of three bird-pollinated Erica species (Erica plukenetii, E. curviflora and E. coccinea), which form part of a large guild of congeneric species that co-flower and share a single pollinator species (Orange-breasted Sunbird Anthobaphes violacea). At least two of the three pre-pollination barriers assessed (distribution ranges, flowering phenology and flower morphology) were weak in each species pair. Hand-pollination experiments revealed that seed set from heterospecific pollination (average 8%) was significantly lower than seed set from outcross pollination (average 50%), supporting the hypothesis that species boundaries are maintained through post-pollination barriers. Reproductive interference, assessed in one population by applying outcross pollen three hours after applying heterospecific pollen, significantly reduced seed set compared to outcross pollen alone. This may drive selection for traits that enhance pre-pollination barriers, particularly given that two of the three species were self-sterile, and therefore pollinator dependent. This study suggests that post-pollination reproductive barriers could facilitate the coexistence of congeneric species, in a recent radiation with weak pre-pollination reproductive barriers.
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Affiliation(s)
- Anina Coetzee
- FitzPatrick Institute of African Ornithology, DSI-NRF Centre of Excellence, University of Cape Town, Private Bag X3, Rondebosch, 7701, South Africa.
| | - Claire N Spottiswoode
- FitzPatrick Institute of African Ornithology, DSI-NRF Centre of Excellence, University of Cape Town, Private Bag X3, Rondebosch, 7701, South Africa
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3EJ, UK
| | - Colleen L Seymour
- FitzPatrick Institute of African Ornithology, DSI-NRF Centre of Excellence, University of Cape Town, Private Bag X3, Rondebosch, 7701, South Africa
- South African National Biodiversity Institute, Kirstenbosch Research Centre, Claremont, 7753, South Africa
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Suetsugu K. Gynomonoecy in a mycoheterotrophic orchid Eulophia zollingeri with autonomous selfing hermaphroditic flowers and putatively outcrossing female flowers. PeerJ 2020; 8:e10272. [PMID: 33194432 PMCID: PMC7597633 DOI: 10.7717/peerj.10272] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 10/08/2020] [Indexed: 11/20/2022] Open
Abstract
Most orchid species exhibit an extreme case of hermaphroditism, owing to the fusion of male and female organs into a gynostemium. Exceptions to this rule have only been reported from the subtribes Catasetinae and Satyriinae. Here, I report an additional orchidaceous example whose flowers are not always hermaphroditic. In several Japanese populations of Eulophia zollingeri (Rchb.f.) J.J.Sm, a widespread Asian and Oceanian orchid, some flowers possess both the anther (i.e., anther cap and pollinaria) and stigma, whereas others possess only the stigma. Therefore, pollination experiments, an investigation of floral morphology and observations of floral visitors were conducted to understand the reproductive biology of E. zollingeri in Miyazaki Prefecture, Japan. It was confirmed that E. zollingeri studied here possesses a gynomonoecious reproductive system, a sexual system in which a single plant has both female flowers and hermaphroditic flowers. In addition, hermaphroditic flowers often possess an effective self-pollination system while female flowers could avoid autogamy but suffered from severe pollinator limitation, due to a lack of agamospermy and low insect-mediated pollination. The present study represents the first documented example of gynomonoecy within Orchidaceae. Gynomonoecy in E. zollingeri may be maintained by the tradeoff in reproductive traits between female flowers (with low fruit set but potential outcrossing benefits) and hermaphroditic flowers (with high fruit set but inbreeding depression in selfed offspring). This mixed mating is probably important in mycoheterotrophic E. zollingeri because it occurs in shaded forest understorey with a paucity of pollinators.
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Affiliation(s)
- Kenji Suetsugu
- Department of Biology, Graduate School of Science, Kobe University, Kobe, Japan
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Morais JM, Consolaro HN, Bergamini LL, Ferrero V. Reproductive biology and pollinators in two enantiostylous Qualea species (Vochysiaceae) in the Brazilian Cerrado. Plant Biol (Stuttg) 2020; 22:872-880. [PMID: 31984595 DOI: 10.1111/plb.13091] [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: 09/19/2019] [Accepted: 01/14/2020] [Indexed: 06/10/2023]
Abstract
Enantiostyly is a floral polymorphism in which two floral forms in the same species differ in deflection of the stigma to right or left position. In monomorphic enantiostylous plants, flowers of the two morphs occur within the same individual, usually in the same proportion. In self-compatible species the function of monomorphic enantiostyly is proposed to increase outcrossing rates and offer a reproductive advantage under pollination limitation. Enantiostylous species are usually self-compatible and show heteranthery, with poricide anthers and pollen as pollinator reward; however, there are families, such as Vochysiaceae, that have different characteristics. We analysed the reproductive system and pollination biology of Qualea parviflora and Q. multiflora, two enantiostylous species from the Brazilian Cerrado that have specific morphological and physiological traits. For this, we characterized flower traits, performed hand pollinations and studied floral visitors. We found no differences between morphs in the proportion of flowers, nectar produced or its concentration, pollen quantity and fruit set. Both species were self-incompatible and quite generalist regarding floral visitors. Enantiostyly in self-incompatible plants seems to confer a reproductive advantage by reducing self-interference resulting from stigma clogging. This novel result helps to expand our knowledge on this complex floral polymorphism and opens new avenues for future research on this topic.
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Affiliation(s)
- J M Morais
- Departament of Botany, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
| | - H N Consolaro
- Departament of Biological Sciences, Institute of Biotecnology, Federal University of Catalão, Catalão, GO, Brazil
| | - L L Bergamini
- Centro de Estudos Ambientais do Cerrado, IBGE Ecological Reserve, Brasília, DF, Brazil
| | - V Ferrero
- Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
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Giglioti R, de Oliveira HN, Gutmanis G, Luciani GF, Azevedo BT, de Carvalho Fiorin CF, de Andrade MF, Silva MAF, Vercesi Filho AE, Katiki LM, Okino CH, de Sena Oliveira MC, Veríssimo CJ. Correlations and repeatability between Babesia spp. infection levels using two dairy cattle breeding systems. Exp Appl Acarol 2020; 81:599-607. [PMID: 32676999 DOI: 10.1007/s10493-020-00515-0] [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] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 06/18/2020] [Indexed: 06/11/2023]
Abstract
Babesia bovis and Babesia bigemina are tick-transmitted piroplasms that cause severe damage to the livestock industry in tropical regions of the world. Recent studies demonstrated differences in infection levels of these haemoparasites among bovine breeds and variation between individual cows regarding resistance to these diseases. This study aimed to estimate the repeatability and correlations between B. bovis and B. bigemina using two cattle breeding systems, an individual system (IS) and a collective paddock system (CPS). All animals were Holstein breed, and the levels of B. bovis and B. bigemina in blood samples were estimated by quantitative polymerase chain reaction (qPCR). The estimated correlations for the B. bigemina and B. bovis DNA copy number for IS and CPS were moderate and high, respectively, whereas repeatability estimates for both systems and both Babesia species were moderate. Although we cannot infer that the type of rearing system directly influenced the correlation and repeatability coefficients, it appears that the bovine parasitemia burden may be dependent on (or determine) the parasitemia burden on ticks because the bovines remained in the same place for a longer time in both systems. Thus, the babesiosis infection levels of the ticks may have been uniform, a phenomenon that also ensures greater uniformity in cattle infection. This factor may have favored the occurrence of infected ticks leading to higher repeatability estimates and correlations. Our study confirms high variability in resistance/susceptibility between breeds, and the high correlations found may be linked to this characteristic and the most intensive breeding type of dairy cattle. Besides, under the present study conditions, the estimated correlations suggest that measuring an infection level of one Babesia species can predict the level of infection of the other.
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Affiliation(s)
- Rodrigo Giglioti
- Instituto de Zootecnia, Rua Heitor Penteado, n. 56, Nova Odessa, São Paulo, 13380 011, Brazil.
| | | | - Gunta Gutmanis
- Instituto de Zootecnia, Rua Heitor Penteado, n. 56, Nova Odessa, São Paulo, 13380 011, Brazil
| | | | - Bianca Tainá Azevedo
- Instituto de Zootecnia, Rua Heitor Penteado, n. 56, Nova Odessa, São Paulo, 13380 011, Brazil
| | | | | | | | | | - Luciana Morita Katiki
- Instituto de Zootecnia, Rua Heitor Penteado, n. 56, Nova Odessa, São Paulo, 13380 011, Brazil
| | | | | | - Cecília José Veríssimo
- Instituto de Zootecnia, Rua Heitor Penteado, n. 56, Nova Odessa, São Paulo, 13380 011, Brazil
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Li C, Mesgaran MB, Ades PK, Cousens RD. Inheritance of breeding system in Cakile (Brassicaceae) following hybridization: implications for plant invasions. Ann Bot 2020; 125:639-650. [PMID: 31802117 PMCID: PMC7102952 DOI: 10.1093/aob/mcz198] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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: 10/10/2019] [Accepted: 12/04/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND AND AIMS Hybridization is commonly assumed to aid invasions through adaptive introgression. In contrast, a recent theoretical model predicted that there can be non-adaptive demographic advantages from hybridization and that the population consequences will depend on the breeding systems of the species and the extent to which subsequent generations are able to interbreed and reproduce. We examined cross-fertilization success and inheritance of breeding systems of two species in order to better assess the plausibility of the theoretical predictions. METHODS Reciprocal artificial crosses were made to produce F1, F2 and backcrosses between Cakile maritima (self-incompatible, SI) and Cakile edentula (self-compatible, SC) (Brassicaceae). Flowers were emasculated prior to anther dehiscence and pollen was introduced from donor plants to the recipient's stigma. Breeding system, pollen viability, pollen germination, pollen tube growth and reproductive output were then determined. The results were used to replace the assumptions made in the original population model and new simulations were made. KEY RESULTS The success rate with the SI species as the pollen recipient was lower than when it was the pollen donor, in quantitative agreement with the 'SI × SC rule' of unilateral incompatibility. Similar outcomes were found in subsequent generations where fertile hybrids were produced but lower success rates were observed in crosses of SI pollen donors with SC pollen recipients. Much lower proportions of SC hybrids were produced than expected from a single Mendelian allele. When incorporated into a population model, these results predicted an even faster rate of replacement of the SC species by the SI species than previously reported. CONCLUSIONS Our study of these two species provides even clearer support for the feasibility of the non-adaptive hybridization hypothesis, whereby the colonization of an SI species can be assisted by transient hybridization with a congener. It also provides novel insight into reproductive biology beyond the F1 generation.
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Affiliation(s)
- Chengjun Li
- School of BioSciences, The University of Melbourne, Melbourne, Victoria, Australia
| | - Mohsen B Mesgaran
- School of BioSciences, The University of Melbourne, Melbourne, Victoria, Australia
| | - Peter K Ades
- School of Ecosystem and Forest Sciences, The University of Melbourne, Melbourne, Victoria, Australia
| | - Roger D Cousens
- School of BioSciences, The University of Melbourne, Melbourne, Victoria, Australia
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Razanajatovo M, Fischer L, van Kleunen M. Do floral traits and the selfing capacity of Mimulus guttatus plastically respond to experimental temperature changes? Oecologia 2019; 192:261-272. [PMID: 31760481 DOI: 10.1007/s00442-019-04558-y] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 11/11/2019] [Indexed: 01/08/2023]
Abstract
Climate change can negatively impact plant-pollinator interactions, and reduce outcross pollination. For reproductive assurance, an increased capacity for autonomous selfing should benefit the persistence of plants under new temperature conditions. Plastic responses of the autonomous selfing capacity to climate change may occur indirectly due to changes in floral traits associated with this capacity. We tested whether the mixed mating plant Mimulus guttatus is capable of plastic changes in floral traits favoring autonomous selfing in response to temperature changes. In seven growth chambers, we grew M. guttatus originating from a large range of latitudes (from 37.89° N to 49.95° N) and thus home temperatures in North America, and experimentally assessed the (autonomous) selfing and outcrossing capacities of the plants. With an increase in the difference between the overall mean daytime and nighttime experimental test temperature and home temperature, flower length and width decreased. The plastic response in flower size suggests that plants may be more successful at autonomous selfing. However, we did not find direct evidence that M. guttatus responded to increased temperature by an increased autonomous selfing capacity. With an increase in temperature difference, the odds of seed production, number of seeds, and individual seed mass decreased. Our results indicate that global warming and the associated increase in extreme temperature events may be detrimental to the reproduction and thus persistence of some plants.
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Affiliation(s)
- Mialy Razanajatovo
- Ecology, Department of Biology, University of Konstanz, Universitätsstrasse 10, 78457, Constance, Germany.
| | - Liliana Fischer
- Ecology, Department of Biology, University of Konstanz, Universitätsstrasse 10, 78457, Constance, Germany
| | - Mark van Kleunen
- Ecology, Department of Biology, University of Konstanz, Universitätsstrasse 10, 78457, Constance, Germany.,Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation, Taizhou University, Taizhou, 318000, China
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15
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Villegas SG, Alcalá RE. Reproductive ecology of the carnivorous plant Pinguicula moranensis (Lentibulariaceae). Plant Biol (Stuttg) 2018; 20:205-212. [PMID: 29083079 DOI: 10.1111/plb.12652] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [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: 06/07/2017] [Accepted: 10/20/2017] [Indexed: 06/07/2023]
Abstract
The interaction of plants with pollinators can be a determinant of their reproductive fitness. However, information about the pollination biology of carnivorous plants is scarce. To increase knowledge of reproductive ecology of carnivorous plants we focused on Pinguicula moranensis. Specifically, based on the presence of large, zygomorphic and spurred flowers, we predicted higher reproductive fitness in cross-pollinated than in self-pollinated flowers. Within a plot of 51 m2 we characterised the reproductive phenology, including flower lifespan and stigmatic receptivity. We identified pollinators and their movement patterns within the plot. Breeding system was experimentally evaluated using hand-pollination (i.e. autonomous, self- and cross-pollination). Flowers of P. moranensis were visited by long-tongued pollinators, mainly members of the Lepidoptera. Hand-pollination experiments confirmed our prediction and suggest that flower traits might favour cross-pollination. We mainly discuss the implications of the patchy distribution of plants and behaviour of pollinators on gene movement in this plant species, as pollination between genetically related individuals could be occurring.
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Affiliation(s)
- S G Villegas
- Departamento de Ecología Evolutiva, Centro de Investigación en Biodiversidad y Conservación, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, México
| | - R E Alcalá
- Departamento de Ecología Evolutiva, Centro de Investigación en Biodiversidad y Conservación, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, México
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16
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Rostás M, Bollmann F, Saville D, Riedel M. Ants contribute to pollination but not to reproduction in a rare calcareous grassland forb. PeerJ 2018; 6:e4369. [PMID: 29479496 PMCID: PMC5822835 DOI: 10.7717/peerj.4369] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 01/24/2018] [Indexed: 11/20/2022] Open
Abstract
The number of plants pollinated by ants is surprisingly low given the abundance of ants and the fact that they are common visitors of angiosperms. Generally ants are considered as nectar robbers that do not provide pollination service. We studied the pollination system of the endangered dry grassland forb Euphorbia seguieriana and found two ant species to be the most frequent visitors of its flowers. Workers of Formica cunicularia carried five times more pollen than smaller Tapinoma erraticum individuals, but significantly more viable pollen was recovered from the latter. Overall, the viability of pollen on ant cuticles was significantly lower (p < 0.001)-presumably an antibiotic effect of the metapleural gland secretion. A marking experiment suggested that ants were unlikely to facilitate outcrossing as workers repeatedly returned to the same individual plant. In open pollinated plants and when access was given exclusively to flying insects, fruit set was nearly 100%. In plants visited by ants only, roughly one third of flowers set fruit, and almost none set fruit when all insects were excluded. The germination rate of seeds from flowers pollinated by flying insects was 31 ± 7% in contrast to 1 ± 1% resulting from ant pollination. We conclude that inbreeding depression may be responsible for the very low germination rate in ant pollinated flowers and that ants, although the most frequent visitors, play a negligible or even deleterious role in the reproduction of E. seguieriana. Our study reiterates the need to investigate plant fitness effects beyond seed set in order to confirm ant-plant mutualisms.
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Affiliation(s)
- Michael Rostás
- Bio-Protection Research Centre, Lincoln University, Lincoln, Canterbury, New Zealand
- Julius-von-Sachs-Institute for Biosciences, Department of Botany II, University of Würzburg, Würzburg, Bavaria, Germany
| | - Felix Bollmann
- Julius-von-Sachs-Institute for Biosciences, Department of Botany II, University of Würzburg, Würzburg, Bavaria, Germany
| | - David Saville
- Saville Statistical Consulting Ltd, Lincoln, Canterbury, New Zealand
| | - Michael Riedel
- Julius-von-Sachs-Institute for Biosciences, Department of Botany II, University of Würzburg, Würzburg, Bavaria, Germany
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Ferreira BHS, Gomes AC, Souza CS, Fabri JR, Sigrist MR. Pollination and reproductive system of synchronopatric species of Cactaceae (Cactoideae) subject to interspecific flow of pollen: an example of ecological adaptation in the Brazilian Chaco. Plant Biol (Stuttg) 2018; 20:101-112. [PMID: 28977737 DOI: 10.1111/plb.12641] [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: 04/28/2017] [Accepted: 09/26/2017] [Indexed: 06/07/2023]
Abstract
Three synchronopatric Cactaceae species, Echinopsis rhodotricha, Harrisia balansae and Praecereus saxicola, have mostly nocturnal anthesis and similar flowers, characteristics that motivated us to perform a comparative study of reproductive ecology. Reproductive phenology was sampled monthly from December 2014 to November 2015. We describe floral biology, breeding system via pollination treatments and evaluate floral visitors from focal and filming observations. Pollen grains found on moth proboscis were compared among cactus species under light microscopy. We used fluorescent dye particles to test intra- and interspecific pollen flow. These three species have extended flowering with greater intensity in the wet season, causing high overlap. They have white and hypocrateriformis flowers that open at twilight or nightfall and last about 15 h. H. balansae seems to be self-incompatible, while E. rhodotricha presented self-compatibility. P. saxicola presented self-fertility, but most of the population seems to be self-incompatible. We suggest sphingophily for the three species, but only P. saxicola was visited by Manduca rustica (Sphingidae). However, we observed pollen grains of all three species on the proboscis of moths, especially M. rustica and M. sexta. Prolonged anthesis allowed bees (herein considered as secondary pollinators) to visit flowers of E. rhodotricha and P. saxicola. It can be concluded that the studied species share nocturnal and diurnal pollinators, suggesting interspecific pollen flow, which, however, could not be detected with fluorescent dye particles. In view of the low frequency of primary pollinators, it appears that these three species have different reproductive strategies, ensuring the fruiting and production of viable seeds.
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Affiliation(s)
- B H S Ferreira
- Programa de Pós Graduação em Biologia Vegetal, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brasil
| | - A C Gomes
- Programa de Pós Graduação em Biologia Vegetal, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brasil
| | - C S Souza
- Programa de Pós Graduação em Ecologia e Conservação, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brasil
| | - J R Fabri
- Laboratório de Botânica, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brasil
| | - M R Sigrist
- Laboratório de Polinização, Reprodução e Fenologia de Plantas, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brasil
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Bittencourt Júnior NS. Evidence for post-zygotic self-incompatibility in Handroanthus impetiginosus (Bignoniaceae). Plant Reprod 2017; 30:69-79. [PMID: 28303339 DOI: 10.1007/s00497-017-0300-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 03/08/2017] [Indexed: 06/06/2023]
Abstract
Late-acting self-incompatibility (LSI) has been defined as a genetically controlled self-sterility mechanism that prevents seed set by selfing, despite normal pollen tube growth and ovule penetration in self-pollinated pistils. In species of the Bignoniaceae with LSI, such as Handroanthus impetiginosus, the selfed pistils are characterized by a marked delay in ovule penetration, fertilization, and endosperm initiation, followed by uniform pistil abscission. This highlights the contentious possibility of a post-zygotic self-incompatibility system. However, previous studies were unable to confirm fusion of the sperm and egg cell nuclei in selfed ovules. In the present study, the cytology of the embryo sac, double fertilization, and pistil longevity was investigated in H. impetiginosus using comparative nuclei microspectrofluorometry of DAPI-stained sections of self- vs. unpollinated pistils. Differences in both pistil longevity and ovary size between self- and unpollinated flowers at the time of pistil abscission were significant. Zygotes with double the DNA content in their nuclei relative to unfertilized egg cell nuclei were verified in selfed ovules from the first day after pollination onward, and G1 karyogamy appeared to have occurred. Our cytological analysis clearly indicates that ovules of self-pollinated pistils in H. impetiginosus are fertilized before pistil abscission but no embryogenesis initiation occurs, which strongly supports the idea of a post-zygotic self-incompatibility mechanism.
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Affiliation(s)
- Nelson Sabino Bittencourt Júnior
- Departamento de Zoologia e Botânica, Instituto de Biociências Letras e Ciências Exatas, Universidade Estadual Paulista "Júlio de Mesquita Filho", Rua Cristóvão Colombo 2265, Jardim Nazareth, CEP 15054-000, São José do Rio Preto, São Paulo, Brazil.
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Chen LN, Cui YZ, Wong KM, Li DZ, Yang HQ. Breeding system and pollination of two closely related bamboo species. AoB Plants 2017; 9:plx021. [PMID: 28685014 PMCID: PMC5493747 DOI: 10.1093/aobpla/plx021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 05/21/2017] [Accepted: 05/27/2017] [Indexed: 05/28/2023]
Abstract
An understanding of the breeding systems and pollination of agriculturally important plants is critical to germplasm improvement. Breeding system characteristics greatly influence the amount and spatial distribution of genetic variation within and amongst populations and influence the rarity and extinction vulnerability of plant species. Many woody bamboos have a long vegetative period (20-150 years) followed by gregarious monocarpy. Relatively, little is known about their pollination and breeding systems. We studied these characteristics in wild Dendrocalamus membranaceus populations and cultivated Dendrocalamus sinicus populations distributed in the Yunnan Province of China. Floral morphology, flower visitors and breeding system were studied from 2013 to 2015. Both bamboos were protogynous, but flowering periods of florets overlapped providing opportunities for self-pollination amongst florets, especially in D. membranaceus. There was no agamospermy in either species. Seed set of D. sinicus was low (0.42 ± 0.42 %) under natural pollination but higher (8.89 ± 2.55 %) after artificial xenogamy. Seed set of D. membranaceus was higher (7.49 ± 0.82 %) in mass flowering populations and 2.14 ± 0.25 % in sporadically flowering populations. The Asian honeybee Apis cerana could provide cross-pollination of D. membranaceus and D. sinicus, and flower visitation peaked at 1000-1200 h. Pollination limitation due to lack of pollinators or pollen was detected in the cultivated populations of D. sinicus and sporadically flowering populations of D. membranaceus. Pollination limitation was not obvious within mass flowering populations. Hand pollination could significantly increase seed set of these two bamboo species. Dendrocalamus membranaceus and D. sinicus were self-compatible and have a mixed-mating system with outcrossing being pre-dominant. Their seed production was limited by the quantity of pollen and pollinator activity. Honeybees were observed as effective pollinators.
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Affiliation(s)
- Ling-Na Chen
- Research Institute of Insect Resources, Chinese Academy of Forestry, Bailongsi, Panlong District, Kunming 650233, China
| | - Yong-Zhong Cui
- Research Institute of Insect Resources, Chinese Academy of Forestry, Bailongsi, Panlong District, Kunming 650233, China
| | - Khoon-Meng Wong
- Singapore Botanic Gardens, 1 Cluny Road, Singapore 259569, Singapore
| | - De-Zhu Li
- Key Laboratory of Biodiversity and Biogeography, Kunming Institute of Botany, Chinese Academy of Sciences, No. 132, Lanhei Road, Panlong District, Kunming 650201, China
| | - Han-Qi Yang
- Research Institute of Insect Resources, Chinese Academy of Forestry, Bailongsi, Panlong District, Kunming 650233, China
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Mesgaran MB, Bouhours J, Lewis MA, Cousens RD. How to be a good neighbour: Facilitation and competition between two co-flowering species. J Theor Biol 2017; 422:72-83. [PMID: 28419864 DOI: 10.1016/j.jtbi.2017.04.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2016] [Revised: 04/09/2017] [Accepted: 04/10/2017] [Indexed: 11/29/2022]
Abstract
Empirical evidence suggests that co-flowering species can facilitate each other through shared pollinators. However, the extent to which one co-flowering species can relieve pollination limitation of another while simultaneously competing for abiotic resource has rarely been examined. Using a deterministic model we explored the demographic outcome for one ("focal") species of its co-occurrence with a species that shares pollinators and competes for both pollinator visitation and abiotic resources. In this paper we showed how the overall impact can be positive or negative, depending on the balance between enhanced fertilization versus increased competition. Our model could predict the density of co-flowering species that will maximize the pollination rate of the focal species by attracting pollinators. Because that density will also give rise to competitive effects, a lower density of co-flowering species is required for optimizing the trade-off between enhanced fertilization and competition so as to give the maximum possible facilitation of reproduction in the focal species. Results were qualitatively different when we considered attractiveness of the co-flowering species, as opposed to its density, because attractiveness, unlike density, had no effect on competition for abiotic resources. Whereas unattractive neighbours would not bring in pollinators, very attractive neighbours would captivate pollinators, not sharing them with the focal species. Thus optimal benefit to the focal species came at intermediate levels of attractiveness in the co-flowering species. This intermediate level of attractiveness in co-flowering species simultaneously maximized pollination and overall facilitation of reproduction for the focal species. The likelihood of facilitation was predicted to decline with the selfing rate of the focal species, revealing an indirect cost for an inbreeding mating system. Whether a co-flowering species can be facilitative depends on the way pollinators respond to the plant density: only a Type III functional response for visitation rate can result in facilitation. Our model provided both a conceptual framework and precise quantitative measures for determining the impacts of a neighbouring co-flowering species on reproduction.
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Affiliation(s)
- Mohsen B Mesgaran
- School of BioSciences, The University of Melbourne, Victoria 3010, Australia.
| | - Juliette Bouhours
- Department of Mathematical and Statistical Sciences, University of Alberta, Alberta, T6G 2G1 Canada
| | - Mark A Lewis
- Department of Mathematical and Statistical Sciences, University of Alberta, Alberta, T6G 2G1 Canada; Department of Biological Sciences, University of Alberta, Alberta, T6G2G1, Canada
| | - Roger D Cousens
- School of BioSciences, The University of Melbourne, Victoria 3010, Australia.
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Wang B, Chen G, Li C, Sun W. Floral characteristics and pollination ecology of Manglietia ventii (Magnoliaceae), a plant species with extremely small populations (PSESP) endemic to South Yunnan of China. Plant Divers 2017; 39:52-59. [PMID: 30159491 PMCID: PMC6112231 DOI: 10.1016/j.pld.2017.01.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 12/26/2016] [Accepted: 01/03/2017] [Indexed: 06/01/2023]
Abstract
Manglietia ventii is a highly endangered plant species endemic to Yunnan province in China, where there are only five known small populations. Despite abundant flowering there is very low fruit and seed set, and very few seedlings in natural populations, indicating problems with reproduction. The causes of low fecundity in M. ventii are not known, largely because of insufficient knowledge of the species pollination ecology and breeding system. We conducted observations and pollination experiments, and analyzed floral scents to understand the pollinator-plant interactions and the role of floral scent in this relationship, as well as the species breeding system. Like the majority of Magnoliaceae, M. ventii has protogynous and nocturnal flowers that emit a strong fragrance over two consecutive evenings. There is a closing period (the pre-staminate stage) during the process of anthesis of a flower, and we characterize the key flowering process as an "open-close-reopen" flowering rhythm with five distinct floral stages observed throughout the floral period of this species: pre-pistillate, pistillate, pre-staminate, staminate, and post-staminate. Flowers are in the pistillate stage during the first night of anthesis and enter the staminate stage the next night. During anthesis, floral scent emission occurs in the pistillate and staminate stages. The effective pollinators were weevils (Sitophilus sp.) and beetles (Anomala sp.), while the role of Rove beetles (Aleochara sp.) and thrips (Thrips sp.) in pollination of M. ventii appears to be minor or absent. The major chemical compounds of the floral scents were Limonene, β-Pinene, α-Pinene, 1,8-Cineole, Methyl-2-methylbutyrate, p-Cymene, Methyl-3-methyl-2-butenoate and 2-Methoxy-2-methyl-3-buten, and the relative proportions of these compounds varied between the pistillate and staminate stages. Production of these chemicals coincided with flower visitation by weevils and beetles. The results of pollination experiments suggest that M. ventii is pollinator-dependent, and low seed set in natural populations is a result of insufficient pollen deposition. Thus, conservation of the species should focus on improving pollination service through the introduction of genetically variable individuals and increase in density of reproducing trees.
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Affiliation(s)
- Bin Wang
- Kunming Botanical Garden, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, Yunnan, China
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, Yunnan, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Gao Chen
- Kunming Botanical Garden, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, Yunnan, China
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, Yunnan, China
| | - Congren Li
- Kunming Botanical Garden, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, Yunnan, China
| | - Weibang Sun
- Kunming Botanical Garden, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, Yunnan, China
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, Yunnan, China
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Slowinski SP, Morran LT, Parrish RC, Cui ER, Bhattacharya A, Lively CM, Phillips PC. Coevolutionary interactions with parasites constrain the spread of self-fertilization into outcrossing host populations. Evolution 2016; 70:2632-2639. [PMID: 27593534 DOI: 10.1111/evo.13048] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 08/20/2016] [Accepted: 08/26/2016] [Indexed: 11/26/2022]
Abstract
Given the cost of sex, outcrossing populations should be susceptible to invasion and replacement by self-fertilization or parthenogenesis. However, biparental sex is common in nature, suggesting that cross-fertilization has substantial short-term benefits. The Red Queen hypothesis (RQH) suggests that coevolution with parasites can generate persistent selection favoring both recombination and outcrossing in host populations. We tested the prediction that coevolving parasites can constrain the spread of self-fertilization relative to outcrossing. We introduced wild-type Caenorhabditis elegans hermaphrodites, capable of both self-fertilization, and outcrossing, into C. elegans populations that were fixed for a mutant allele conferring obligate outcrossing. Replicate C. elegans populations were exposed to the parasite Serratia marcescens for 33 generations under three treatments: a control (avirulent) parasite treatment, a fixed (nonevolving) parasite treatment, and a copassaged (potentially coevolving) parasite treatment. Self-fertilization rapidly invaded C. elegans host populations in the control and the fixed-parasite treatments, but remained rare throughout the entire experiment in the copassaged treatment. Further, the frequency of the wild-type allele (which permits selfing) was strongly positively correlated with the frequency of self-fertilization across host populations at the end of the experiment. Hence, consistent with the RQH, coevolving parasites can limit the spread of self-fertilization in outcrossing populations.
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Affiliation(s)
| | - Levi T Morran
- Department of Biology, Emory University, Atlanta, Georgia 30322
| | | | - Eric R Cui
- Department of Biology, Indiana University, Bloomington, IN 47401
| | | | - Curtis M Lively
- Department of Biology, Indiana University, Bloomington, IN 47401
| | - Patrick C Phillips
- Institute of Ecology and Evolution, University of Oregon, Eugene, OR 97403
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Giussani LM, Gillespie LJ, Scataglini MA, Negritto MA, Anton AM, Soreng RJ. Breeding system diversification and evolution in American Poa supersect. Homalopoa (Poaceae: Poeae: Poinae). Ann Bot 2016; 118:281-303. [PMID: 27373539 PMCID: PMC4970369 DOI: 10.1093/aob/mcw108] [Citation(s) in RCA: 3] [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: 12/11/2015] [Revised: 02/18/2016] [Accepted: 03/18/2016] [Indexed: 05/29/2023]
Abstract
BACKGROUND AND AIMS Poa subgenus Poa supersect. Homalopoa has diversified extensively in the Americas. Over half of the species in the supersection are diclinous; most of these are from the New World, while a few are from South-East Asia. Diclinism in Homalopoa can be divided into three main types: gynomonoecism, gynodioecism and dioecism. Here the sampling of species of New World Homalopoa is expanded to date its origin and diversification in North and South America and examine the evolution and origin of the breeding system diversity. METHODS A total of 124 specimens were included in the matrix, of which 89 are species of Poa supersect. Homalopoa sections Acutifoliae, Anthochloa, Brizoides, Dasypoa, Dioicopoa, Dissanthelium, Homalopoa sensu lato (s.l.), Madropoa and Tovarochloa, and the informal Punapoa group. Bayesian and parsimony analyses were conducted on the data sets based on four markers: the nuclear ribosomal internal tanscribed spacer (ITS) and external transcribed spacer (ETS), and plastid trnT-L and trnL-F. Dating analyses were performed on a reduced Poa matrix and enlarged Poaceae outgroup to utilize fossils as calibration points. A relaxed Bayesian molecular clock method was used. KEY RESULTS Hermaphroditism appears to be pleisiomorphic in the monophyletic Poa supersect. Homalopoa, which is suggested to have originated in Eurasia 8·4-4·2 million years ago (Mya). The ancestor of Poa supersect. Homalopoa radiated throughout the New World in the Late Miocene-Early Pliocene, with major lineages originating during the Pliocene to Pleistocene (5-2 Mya). Breeding systems are linked to geographic areas, showing an evolutionary pattern associated with different habitats. At least three major pathways from hermaphroditism to diclinism are inferred in New World Homalopoa: two leading to dioecism, one via gynodioecism in South America and another directly from hermaphroditism in North America, a result that needs to be checked with a broader sampling of diclinous species in North America. A third pathway leads from hermaphroditism to gynomonoecism in Andean species of South America, with strictly pistillate species evolving in the highest altitudes. CONCLUSIONS Divergence dating provides a temporal context to the evolution of breeding systems in New World Poa supersect. Homalopoa The results are consistent with the infrageneric classification in part; monophyletic sections are confirmed, it is proposed to reclassify species of sect. Acutifoliae, Dasypoa and Homalopoa s.l. and it is acknowledged that revision of the infrageneric taxonomy of the gynomonoecious species is needed.
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Affiliation(s)
| | - Lynn J Gillespie
- Research and Collections Division, Canadian Museum of Nature, Ottawa, Ontario, Canada
| | | | | | - Ana M Anton
- Instituto Multidisciplinario de Biología Vegetal (IMBIV), CONICET-UNC, Córdoba, Argentina
| | - Robert J Soreng
- Department of Botany, Smithsonian Institution, Washington, DC, USA
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Chen M, Zhao XY, Zuo XA, Mao W, Qu H, Zhu YC. Effects of habitat disturbance on the pollination system of Ammopiptanthus mongolicus (Maxim) Cheng f. at the landscape-level in an arid region of Northwest China. J Plant Res 2016; 129:435-447. [PMID: 26780064 DOI: 10.1007/s10265-015-0779-7] [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: 04/20/2015] [Accepted: 11/09/2015] [Indexed: 06/05/2023]
Abstract
Ammopiptanthus mongolicus is an ecologically important species in the arid region of Northwest China. Habitat disturbance can significantly affect plant mating success and ultimately species viability. Pollen limitation of plant reproduction occurs in many plant species, particularly those under habitat disturbance. However, previous investigations have demonstrated differences in pollen limitation between conserved and disturbed sites. We compared the phenology, pollen limitation, pollinators and breeding system of both sites to determine whether habitat disturbance has generated changes in these plant components. We found that the species differed in four aspects. First, blooming duration and flowering peak were longer in the disturbed site than in the conserved site. Second, A. mongolicus can be pollen-limited and pollen limitation was more intense in the conserved site than in the disturbed site. Third, Anthophora uljanini was found to be a frequent pollinator in the conserved site, while Apis mellifera was the most effective and frequent flower visitor. More pollinator visits were recorded in the disturbed site, which could explain the differences in reproductive success. Finally, seed set was higher in the disturbed site than in the conserved site. We found that outcrossing was dominant in both sites and that agamospermy and self-pollination played complementary roles to ensure reproduction. Differences in flower production influenced by artificial selection and pollinator type explain the different seed set in both sites, whereas habitat disturbance cause changes differences in the pollination process and limits pollen flow. The balance between artificial management and mating success is crucial to analysis of the pollination process and manipulation of A. mongolicus population size.
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Affiliation(s)
- Min Chen
- Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, China.
| | - Xue-Yong Zhao
- Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Xiao-An Zuo
- Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Wei Mao
- Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Hao Qu
- Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Yang-Chun Zhu
- Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
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25
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Watanabe K, Yang TYA, Nishihara C, Huang TL, Nakamura K, Peng CI, Sugawara T. Distyly and floral morphology of Psychotria cephalophora (Rubiaceae) on the oceanic Lanyu (Orchid) Island, Taiwan. Bot Stud 2015; 56:10. [PMID: 28510819 PMCID: PMC5432894 DOI: 10.1186/s40529-015-0091-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 04/28/2015] [Indexed: 05/28/2023]
Abstract
BACKGROUND Psychotria cephalophora Merr. (Rubiaceae), a shrub in oceanic islands of Taiwan and the Philippines, appears to be distylous, but distyly is usually rare on oceanic islands. To elucidate the functional breeding system of P. cephalophora can improve our understanding of plant reproductive ecology on oceanic islands. RESULTS Field investigations on Lanyu (Orchid Island) off the coast of southeastern Taiwan revealed the flowers to be distylous with short (S)- and long (L)-styled morphs, with only one morph per individual. Laboratory observations revealed that both morphs had stainable pollen grains and indicated dimorphism in stigmatic papillae and pollen size. In hand pollination experiments, the pollen tubes reached the base of the style in intermorph crossing, whereas they rarely penetrated stylar tissue in intramorph crossing and selfing. Open pollinated S- and L-styled flowers produced fruit. CONCLUSIONS The results indicate that the breeding system of P. cephalophora is morphologically and functionally distylous.
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Affiliation(s)
- Kenta Watanabe
- Okinawa National College of Technology, 905 Henoko, Nago 905-2192 Okinawa, Japan
| | - T Y Aleck Yang
- Department of Botany, National Museum of Natural Science, Kuan Chien Rd, Taichung, 404 Taiwan
- Department of Life Science, National Chung Hsin University, Taichung, 402 Taiwan
| | | | - Tai-Liang Huang
- Department of Botany, National Museum of Natural Science, Kuan Chien Rd, Taichung, 404 Taiwan
| | - Koh Nakamura
- Botanic Garden, Field Science Center for Northern Biosphere, Hokkaido University, North 3, West 8, Chuo-ku, Sapporo, 060-0003 Japan
| | - Ching-I Peng
- Biodiversity Research Center, Academia Sinica, Taipei 115, Nangang, Taiwan
| | - Takashi Sugawara
- Makino Herbarium, Graduate School of Science, Tokyo Metropolitan University, 1-1 Minami-Ohsawa, Hachioji, Tokyo, 192-0397 Japan
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Argüelles-Ticó A, Küpper C, Kelsh RN, Kosztolányi A, Székely T, van Dijk RE. Geographic variation in breeding system and environment predicts melanin-based plumage ornamentation of male and female Kentish plovers. Behav Ecol Sociobiol 2016; 70:49-60. [PMID: 26766883 DOI: 10.1007/s00265-015-2024-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 10/09/2015] [Accepted: 10/12/2015] [Indexed: 11/17/2022]
Abstract
Sexual selection determines the elaboration of morphological and behavioural traits and thus drives the evolution of phenotypes. Sexual selection on males and females can differ between populations, especially when populations exhibit different breeding systems. A substantial body of literature describes how breeding systems shape ornamentation across species, with a strong emphasis on male ornamentation and female preference. However, whether breeding system predicts ornamentation within species and whether similar mechanisms as in males also shape the phenotype of females remains unclear. Here, we investigate how different breeding systems are associated with male and female ornamentation in five geographically distinct populations of Kentish plovers Charadrius alexandrinus. We predicted that polygamous populations would exhibit more elaborate ornaments and stronger sexual dimorphism than monogamous populations. By estimating the size and intensity of male (n = 162) and female (n = 174) melanin-based plumage ornaments, i.e. breast bands and ear coverts, we show that plumage ornamentation is predicted by breeding system in both sexes. A difference in especially male ornamentation between polygamous (darker and smaller ornaments) and monogamous (lighter and larger) populations causes the greatest sexual dimorphism to be associated with polygamy. The non-social environment, however, may also influence the degree of ornamentation, for instance through availability of food. We found that, in addition to breeding system, a key environmental parameter, rainfall, predicted a seasonal change of ornamentation in a sex-specific manner. Our results emphasise that to understand the phenotype of animals, it is important to consider both natural and sexual selection acting on both males and females.
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27
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Yang LY, Machado CA, Dang XD, Peng YQ, Yang DR, Zhang DY, Liao WJ. The incidence and pattern of copollinator diversification in dioecious and monoecious figs. Evolution 2015; 69:294-304. [PMID: 25495152 PMCID: PMC4328460 DOI: 10.1111/evo.12584] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2014] [Accepted: 11/21/2014] [Indexed: 01/08/2023]
Abstract
Differences in breeding system are associated with correlated ecological and morphological changes in plants. In Ficus, dioecy and monoecy are strongly associated with different suites of traits (tree height, population density, fruiting frequency, pollinator dispersal ecology). Although approximately 30% of fig species are pollinated by multiple species of fig-pollinating wasps, it has been suggested that copollinators are rare in dioecious figs. Here, we test whether there is a connection between the fig breeding system and copollinator incidence and diversification by conducting a meta-analysis of molecular data from pollinators of 119 fig species that includes new data from 15 Asian fig species. We find that the incidence of copollinators is not significantly different between monoecious and dioecious Ficus. Surprisingly, while all copollinators in dioecious figs are sister taxa, only 32.1% in monoecious figs are sister taxa. We present hypotheses to explain those patterns and discuss their consequences on the evolution of this mutualism.
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Affiliation(s)
- Li-Yuan Yang
- State Key Laboratory of Earth Surface Processes and Resource Ecology and MOE Key Laboratory for Biodiversity Science and Ecological Engineering, College of Life Sciences, Beijing Normal UniversityBeijing, 100875, China
| | - Carlos A Machado
- Department of Biology, University of Maryland1210 Biology-Psychology Building, College Park, Maryland, 20742
| | - Xiao-Dong Dang
- State Key Laboratory of Earth Surface Processes and Resource Ecology and MOE Key Laboratory for Biodiversity Science and Ecological Engineering, College of Life Sciences, Beijing Normal UniversityBeijing, 100875, China
| | - Yan-Qiong Peng
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of SciencesKunming, 650223, China
| | - Da-Rong Yang
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of SciencesKunming, 650223, China
| | - Da-Yong Zhang
- State Key Laboratory of Earth Surface Processes and Resource Ecology and MOE Key Laboratory for Biodiversity Science and Ecological Engineering, College of Life Sciences, Beijing Normal UniversityBeijing, 100875, China
| | - Wan-Jin Liao
- State Key Laboratory of Earth Surface Processes and Resource Ecology and MOE Key Laboratory for Biodiversity Science and Ecological Engineering, College of Life Sciences, Beijing Normal UniversityBeijing, 100875, China
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28
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Guerra TJ, Galetto L, Silva WR. Nectar secretion dynamic links pollinator behavior to consequences for plant reproductive success in the ornithophilous mistletoe Psittacanthus robustus. Plant Biol (Stuttg) 2014; 16:956-966. [PMID: 24641568 DOI: 10.1111/plb.12146] [Citation(s) in RCA: 7] [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: 08/13/2013] [Accepted: 11/20/2013] [Indexed: 06/03/2023]
Abstract
The mistletoe Psittacanthus robustus was studied as a model to link flower phenology and nectar secretion strategy to pollinator behaviour and the reproductive consequences for the plant. The bright-coloured flowers presented diurnal anthesis, opened asynchronously throughout the rainy season and produced copious dilute nectar as the main reward for pollinators. Most nectar was secreted just after flower opening, with little sugar replenishment after experimental removals. During the second day of anthesis in bagged flowers, the flowers quickly reabsorbed the offered nectar. Low values of nectar standing crop recorded in open flowers can be linked with high visitation rates by bird pollinators. Eight hummingbirds and two passerines were observed as potential pollinators. The most frequent flower visitors were the hummingbirds Eupetomena macroura and Colibri serrirostris, which actively defended flowering mistletoes. The spatial separation between anthers, stigma and nectar chamber promotes pollen deposition on flapping wings of hovering hummingbirds that usually probe many flowers per visit. Seed set did not differ between hand-, self- and cross-pollinated flowers, but these treatments set significantly more seeds than flowers naturally exposed to flower visitors. We suggest that the limitation observed in the reproductive success of this plant is not related to pollinator scarcity, but probably to the extreme frequency of visitation by territorial hummingbirds. We conclude that the costs and benefits of plant reproduction depend on the interaction strength between flowers and pollinators, and the assessment of nectar secretion dynamics, pollinator behaviour and plant breeding system allows clarification of the complexity of such associations.
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Affiliation(s)
- T J Guerra
- Programa de Pós-Graduação em Ecologia, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil
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29
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Gao JY, Liu Q, Li QJ. The comparative reproductive biology of a tetraploid species, Hedychium villosum, and its diploid progenitor H. tenuiflorum (Zingiberaceae). Plant Biol (Stuttg) 2014; 16:683-689. [PMID: 23957369 DOI: 10.1111/plb.12080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Accepted: 06/20/2013] [Indexed: 06/02/2023]
Abstract
The evolutionary advantages of polyploidy may result from a number of changes in floral traits and breeding system, which may enable polyploids to exploit new habitats and become widespread. In this study, we comparatively investigated the floral biology of the tetraploid species Hedychium villosum and its diploid progenitor H. tenuiflorum, to assess reproductive divergence between the two species. The results showed that flowers of the tetraploid species last longer and produce more nectar than did diploid species. The flowering times of the two species did not overlap at all. Observations of floral visitors in natural populations demonstrated that butterflies and hawkmoths were effective pollinators of both species, but there was a significant difference in butterfly and hawkmoth assemblages between the two species. The hand-pollination experiments and pollen tube growth experiments suggested that diploid H. tenuiflorum was self-incompatible, while tetraploid H. villosum was completely self-compatible. H. villosum has a much wider distribution range and occupies more diverse habitats than H. tenuiflorum. Polyploidisation may enable tetraploid H. villosum to exploit new habitats previously unavailable to diploid H. tenuiflorum.
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Affiliation(s)
- J Y Gao
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, China
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Somme L, Mayer C, Raspé O, Jacquemart AL. Influence of spatial distribution and size of clones on the realized outcrossing rate of the marsh cinquefoil (Comarum palustre). Ann Bot 2014; 113:477-87. [PMID: 24284813 PMCID: PMC3906973 DOI: 10.1093/aob/mct280] [Citation(s) in RCA: 6] [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] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
BACKGROUND AND AIMS Clonal growth is a common feature in flowering plants. As clone size increases, the selfing rate in self-compatible species is likely to increase due to more frequent geitono-pollination events (i.e. pollination among flowers within the same genet). This study investigated the breeding system of the marsh cinquefoil (Comarum palustre) and assessed spatial distribution of clones, clone size and architecture, and their effects on realized outcrossing rates. In addition, pollen dispersal was investigated in two patchy populations. METHODS The species' breeding system was investigated under controlled conditions through hand pollinations (self- vs. cross-pollination). Using microsatellite markers, an assessment was made of the realized outcrossing rates and the genetic diversity in four natural populations, the clonal structure in two populations within five 15 × 15 m sampling plots following 0.5 × 0.5 m grids, and the pollen dispersal through paternity assignment tests in those two populations. KEY RESULTS Comarum palustre is a self-compatible species but only presents a low rate of spontaneous self-pollination. The occurrence of inbreeding depression was not detected at the seed set stage (δ(SS) = 0.04). Clones were spatially clumped (A(C) = 0.60-0.80), with intermediate to no intermingling of the ramets (D(C) = 0.40-1.00). Genet size ranged from one to 171 ramets. Patchy populations had low outcrossing rates (t(m) = 0.33-0.46). Large clones showed lower outcrossing rates than small clones. Pollen dispersal mainly occurred within patches as only 1-7 % of the pollination events occurred between patches of >25 m separation. Seedling recruitment events were detected. CONCLUSIONS Genet size together with distances between patches, through increasing geitono-pollination events, appeared to be important factors influencing realized outcrossing rates. The study also revealed seed flow allowing seedling recruitment, which may contribute to increasing the number of new patches, and potentially further enhance gene flow within populations.
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Affiliation(s)
- L. Somme
- Earth and Life Institute-Research group Genetics, Reproduction, Populations, Université catholique de Louvain, Croix du Sud 2, Box L705 14, B-1348 Louvain-la-Neuve, Belgium
- For correspondence. E-mail
| | - C. Mayer
- Earth and Life Institute-Research group Genetics, Reproduction, Populations, Université catholique de Louvain, Croix du Sud 2, Box L705 14, B-1348 Louvain-la-Neuve, Belgium
| | - O. Raspé
- National Botanic Garden of Belgium, Domein van Bouchout, B-1860 Meise, Belgium
| | - A.-L. Jacquemart
- Earth and Life Institute-Research group Genetics, Reproduction, Populations, Université catholique de Louvain, Croix du Sud 2, Box L705 14, B-1348 Louvain-la-Neuve, Belgium
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31
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de Vos JM, Wüest RO, Conti E. Small and ugly? Phylogenetic analyses of the "selfing syndrome" reveal complex evolutionary fates of monomorphic primrose flowers. Evolution 2014; 68:1042-57. [PMID: 24325205 DOI: 10.1111/evo.12331] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 11/18/2013] [Indexed: 01/10/2023]
Abstract
One of the most common trends in plant evolution, loss of self-incompatibility and ensuing increases in selfing, is generally assumed to be associated with a suite of phenotypic changes, notably a reduction of floral size, termed the selfing syndrome. We investigate whether floral morphological traits indeed decrease in a deterministic fashion after losses of self-incompatibility, as traditionally expected, using a phylogeny of 124 primrose species containing nine independent transitions from heterostyly (heteromorphic incompatibility) to homostyly (monomorphic self-compatibility), a classic system for evolution of selfing. We find similar overall variability of homostylous and heterostylous species, except for diminished herkogamy in homostyles. Bayesian mixed models demonstrate differences between homostylous and heterostylous species in all traits, but net effects across species are small (except herkogamy) and directionality differs among traits. Strongly drift-like evolutionary trajectories of corolla tube length and corolla diameter inferred by Ornstein-Uhlenbeck models contrast with expected deterministic trajectories toward small floral size. Lineage-specific population genetic effects associated with evolution of selfing may explain that reductions of floral size represent one of several possible outcomes of floral evolution after loss of heterostyly in primroses. Contrary to the traditional paradigm, selfing syndromes may, but do not necessarily evolve in response to increased selfing.
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Affiliation(s)
- Jurriaan M de Vos
- Institute of Systematic Botany, University of Zürich, Zollikerstrasse 107, 8008 Zürich, Switzerland; Department of Ecology and Evolutionary Biology, Brown University, 80 Waterman St., Box G-W, Providence, Rhode Island, 02912.
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Gan X, Cao L, Zhang X, Li H. Floral biology, breeding system and pollination ecology of an endangered tree Tetracentron sinense Oliv. (Trochodendraceae). Bot Stud 2013; 54:50. [PMID: 28510885 PMCID: PMC5430371 DOI: 10.1186/1999-3110-54-50] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Accepted: 10/21/2013] [Indexed: 06/01/2023]
Abstract
BACKGROUND Tetracentron sinense Oliv. is an endangered tree mainly distributed in south-central China. The breeding system and pollination ecology of T. sinense are unclear. With a conservation perspective, the floral biology, breeding system and pollination ecology of Tetracentron sinense Oliv. were investigated, in order to discuss the endangered factors related to pollination, and to provide important information for its conservation. RESULTS Our results revealed four important aspects of the reproductive biology of T. sinense. 1) T. sinense usually flowers by the beginning of June, and the flowering period of the population is about two months, and the florescence of florets lasted for 15 to 24 days with delicate fragrance. 2) The pollen/ovule ratio is 720 ± 28, and the outcrossing index is three. Artificial pollination experiments showed that T. sinense is self-compatible, with facultative xenogamy and no indication of agamospermy. 3) The pollination syndrome is ambophily, and self-pollination plays an important role in fruit production if wind and insect pollination is unavailable. 4) Insect pollinators were predominantly represented by Coleoptera, Diptera and Hymenoptera. Syrphid fly and bees were the main effective pollinators. CONCLUSIONS The results suggested that T. sinense exhibits a mixed-mating system, and autogamy in its breeding system may provide reproductive assurance for the population maintenance. During flowering and pollination in natural population, the decrease of population density and harsh environmental condition might be one of crucial reasons resulting in endanger for this species.
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Affiliation(s)
- Xiaohong Gan
- College of Life Science, China West Normal University, Nanchong, 637009 PR. China
- Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), China West Normal University, Nanchong, 637009 PR. China
| | - Lingling Cao
- College of Life Science, China West Normal University, Nanchong, 637009 PR. China
- Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), China West Normal University, Nanchong, 637009 PR. China
| | - Xia Zhang
- Library of China West Normal University, Nanchong, 637009 PR. China
| | - Huaichun Li
- College of Life Science, China West Normal University, Nanchong, 637009 PR. China
- Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), China West Normal University, Nanchong, 637009 PR. China
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Almeida NM, Castro CC, Leite AV, Novo RR, Machado IC. Floral polymorphism in Chamaecrista flexuosa (Fabaceae-Caesalpinioideae): a possible case of atypical enantiostyly? Ann Bot 2013; 112:1117-1123. [PMID: 24026440 PMCID: PMC3783247 DOI: 10.1093/aob/mct188] [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: 05/15/2013] [Accepted: 06/27/2013] [Indexed: 06/02/2023]
Abstract
BACKGROUND AND AIMS Reciprocal herkogamy, including enantiostyly and heterostyly, involves reciprocity in the relative positions of the sexual elements within the flower. Such systems result in morphologically and, since pollen is deposited on and captured from different parts of the pollinator, functionally distinct floral forms. Deviations from the basic pattern may modify the functionality of these mechanisms. For heterostylous species, such deviations are generally related to environmental disturbances, pollination services and/or reduced numbers of one floral morph. Deviations for enantiostylous species have not yet been reported. This study aims to investigate enantiostyly in Chamaecrista flexuosa, in particular the presence of deviations from the standard form, in an area of coastal vegetation in north-east Brazil. METHODS Observations and investigations of floral biology, the reproductive system, pollinator behaviour, floral morphology and morphometry were performed. KEY RESULTS In C. flexuosa flowers, anthers of different size but similar function are grouped. The flowers were self-compatible and set fruits after every treatment, except in the spontaneous self-pollination experiment, thereby indicating their dependence on pollen vectors. The flowers were pollinated by bees, especially Xylocopa cearensis and X. grisencens. Pollen is deposited and captured from the ventral portion of the pollinator's body. Variations in the spatial arrangement of floral elements allowed for the identification of floral morphs based on both morphological and functional criteria. Using morphological criteria, morphologically right (MR) and morphologically left (ML) floral morphs were identified. Three floral morphs were identified using functional criteria: functionally right (FR), functionally central (FC) and functionally left (FL). Combinations of morphologically and functionally defined morphs did not occur in equal proportions. There was a reduced frequency of the MR-FR combination. CONCLUSIONS The results indicate the occurrence of an atypical enantiostyly in C. flexuosa. This seems to improve reproductive success by increasing the efficiency of pollen deposition and capture.
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Affiliation(s)
| | | | - Ana Virgínia Leite
- Departamento de Biologia, Universidade Federal Rural de Pernambuco, Rua Dom Manoel de Medeiros, s/n, 51280-400, Recife-PE, Brazil
| | | | - Isabel Cristina Machado
- Centro de Ciências Biológicas, Departamento de Botânica, Universidade Federal de Pernambuco, Avenida Professor Moraes Rego, 1235, 50670-901, Recife-PE, Brazil
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Pruvost NBM, Hoffmann A, Reyer HU. Gamete production patterns, ploidy, and population genetics reveal evolutionary significant units in hybrid water frogs (Pelophylax esculentus). Ecol Evol 2013; 3:2933-46. [PMID: 24101984 PMCID: PMC3790541 DOI: 10.1002/ece3.687] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 06/14/2013] [Accepted: 06/17/2013] [Indexed: 12/05/2022] Open
Abstract
The European water frog Pelophylax esculentus is a natural hybrid between P. lessonae (genotype LL) and P. ridibundus (RR). It reproduces through hybridogenesis, eliminating one parental genome from its germline and producing gametes containing the genome of the other parental species. According to previous studies, this elimination and transmission pattern is very diverse. In mixed populations, where only diploid hybrids (LR) live in sympatry and mate with one or both parental species, the excluded genome varies among regions, and the remaining genome is transmitted clonally to haploid gametes. In all-hybrid populations consisting of diploid (LR) and triploid (LLR and/or LRR) frogs, diploid individuals also produce gametes clonally (1n in males, 2n in females), whereas triploids eliminate the genome they have in single copy and produce haploid gametes containing the recombined other genome. However, here, too, regional differences seem to exist, and some triploids have been reported to produce diploid gametes. In order to systematically study such regional and genotype differences in gamete production, their potential origin, and their consequences for the breeding system, we sampled frogs from five populations in three European countries, performed crossing experiments, and investigated the genetic variation through microsatellite analysis. For four populations, one in Poland, two in Germany, and one in Slovakia, our results confirmed the elimination and transmission pattern described above. In one Slovakian population, however, we found a totally different pattern. Here, triploid males (LLR) produce sperm with a clonally transmitted diploid LL genome, rather than a haploid recombined L genome, and LR females clonally produce haploid R eggs, rather than diploid LR eggs. These differences among the populations in gamete production go along with differences in genomotype composition, breeding system (i.e., the way triploids are produced), and genetic variation. These differences are strong evidence for a polyphyletic origin of triploids. Moreover, our findings shed light on the evolutionary potential inherent to the P. esculentus complex, where rare events due to untypical gametogenetic processes can lead to the raise, the perpetuation, and the dispersion of new evolutionary significant lineages which may also deserve special conservation measures.
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Affiliation(s)
- Nicolas B M Pruvost
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich Winterthurerstrasse 190, 8057, Zurich, Switzerland
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Redmond AM, Robbins LE, Travis J. The effects of pollination distance on seed production in three populations of Amianthium muscaetoxicum (Liliaceae). Oecologia 1989; 79:260-4. [PMID: 28312863 DOI: 10.1007/BF00388486] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/1988] [Indexed: 10/26/2022]
Abstract
We examined the effects of varying pollination distances on seed production and its components in three populations of the perennial lily Amianthium muscaetoxicum. We performed hand pollinations using pollen from near neighbors and from plants separated by 5, 15, and 60 meters. Pollination by near neighbors reduced fruit set and the numbers of seeds per fruit in comparison to other treatments in two of the three populations; variation in pollination distance beyond near-neighbor pollination produced no effect. In the third population, in which nearneighbor pollination did not affect seed production, nearneighbor pollination reduced seed weight by 11%, compared to other pollination distances. Seed weights from the 5-, 15-, and 60-m pollination treatments did not differ, and pollination distance did not affect seed weight in the other two populations. The effects of pollination-distance treatments explained a very small proportion of the variance in seed production and seed weight. Heterogeneity among individual plants, despite full hand pollination of every plant, accounted for much more variance (by one to two orders of magnitude) than variation in pollination distance.
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