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Barman M, Tenhaken R, Dötterl S. Negative and sex-specific effects of drought on flower production, resources and pollinator visitation, but not on floral scent in monoecious Cucurbita pepo. THE NEW PHYTOLOGIST 2024; 244:1013-1023. [PMID: 39117354 DOI: 10.1111/nph.20016] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Accepted: 04/10/2024] [Indexed: 08/10/2024]
Abstract
The globally changing climatic condition is increasing the incidences of drought in several parts of the world. This is predicted and already shown to not only impact plant growth and flower development, but also plant-pollinator interactions and the pollination success of entomophilous plants. However, there is a large gap in our understanding of how drought affects the different flowers and pollen transfer among flowers in sexually polymorphic species. Here, we evaluated in monoecious Styrian oil pumpkin, and separately for female and male flowers, the responses of drought stress on flower production, petal size, nectar, floral scent and visitation by bumblebee pollinators. Drought stress adversely affected all floral traits studied, except floral scent. Although both flower sexes were adversely affected by drought stress, the effects were more severe on female flowers, with most of the female flowers even aborted before opening. The drought had negative effects on floral visitation by the pollinators, which generally preferred female flowers. Overall, our study highlights that the two flower sexes of a monoecious plant species are differently affected by drought stress and calls for further investigations to better understand the cues used by the pollinators to discriminate against male flowers and against flowers of drought-stressed plants.
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Affiliation(s)
- Monica Barman
- Department of Environment and Biodiversity, Paris Lodron University of Salzburg, Hellbrunnerstrasse 34, Salzburg, 5020, Austria
- Leibniz Institute of Vegetable and Ornamental Crops (IGZ), Theodor-Echtermeyer-Weg 1, Großbeeren, 14979, Germany
| | - Raimund Tenhaken
- Department of Environment and Biodiversity, Paris Lodron University of Salzburg, Hellbrunnerstrasse 34, Salzburg, 5020, Austria
| | - Stefan Dötterl
- Department of Environment and Biodiversity, Paris Lodron University of Salzburg, Hellbrunnerstrasse 34, Salzburg, 5020, Austria
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2
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Ramadoss N, Steele S, Flores-Rentería L. Influence of sexual dimorphism and dichromatism on reproductive success in a rare native cactus. Oecologia 2023; 203:383-394. [PMID: 37955714 DOI: 10.1007/s00442-023-05473-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 10/27/2023] [Indexed: 11/14/2023]
Abstract
Identifying plant sexual dimorphic traits is critical in advancing our knowledge on plant-pollinator interactions. For example, dimorphism in floral colors, or sexual dichromatism, is a crucial mediator of pollinator choice on foraging decisions. We studied Cylindropuntia wolfii, a model system, with diverse flower colors and a functionally dioecious sexual system. However, evidence suggests that sexual reproduction is limited in this species as it has a low seed set especially in naturally pollinated fruits. Thus, it is critical to this native species' conservation to investigate its relationship with pollinators. Our goals were to: (a) investigate the sexual dimorphism including the sexual dichromatism in the flowers of the cactus, and (b) determine whether sexually dimorphic traits affect the pollinator attraction of both the sexes. We measured several quantitative and qualitative traits and compared them between male and female flowers. Then we recorded the pollinator visitation rate in nature for both sexes and tracked pollinator color preference using fluorescent dyes as pollen analogues. Our study showed that male flowers of C. wolfii are bigger and brighter, and they attract more potential pollinators than females, supporting the hypothesis that sexual dimorphism influences pollinator visitation preference. Fluorescence dichromatism, in which female flowers' anthers fluoresce more than male flower anthers suggest this could be female flowers' strategy to compensate for their dark colors and small size. The results from this study showed that C. wolfii exhibits sexual dichromatism and fluorescence dichromatism, which is a novel finding in plant research.
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Affiliation(s)
| | - Scarlet Steele
- Department of Biology, San Diego State University, San Diego, CA, USA
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3
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Nowak S, Olędrzyńska N, Szlachetko DL, Dudek M. Notes to the Taxonomic Affiliation of the Bulbophyllym Sect. Physometra (Orchidaceae, Epidendroideae) Based on Molecular Phylogenetic Analyses. Int J Mol Sci 2023; 24:ijms24119709. [PMID: 37298660 DOI: 10.3390/ijms24119709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 05/28/2023] [Accepted: 05/30/2023] [Indexed: 06/12/2023] Open
Abstract
To solve the taxonomic affiliation of Bulbophyllum physometrum, the only known species of the Bulbophyllym sect. Physometra (Orchidaceae, Epidendroideae), we conducted phylogenetic analyses based on nuclear markers, i.e., ITS and the low-copy gene Xdh, and the plastid region matK. We used Asian Bulbophyllum taxa, with a special focus on species from the sections Lemniscata and Blepharistes, i.e., the only Asian sections of this genus with bifoliate pseudobulbs, as in B. physometrum. Unexpectedly, the results of molecular phylogenetic analyses showed that B. physometrum is most probably more related to the representatives of the sections Hirtula and Sestochilos than Blepharistes or Lemniscata.
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Affiliation(s)
- Sławomir Nowak
- Department of Plant Taxonomy and Nature Conservation, Faculty of Biology, The University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland
| | - Natalia Olędrzyńska
- Department of Plant Taxonomy and Nature Conservation, Faculty of Biology, The University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland
| | - Dariusz L Szlachetko
- Department of Plant Taxonomy and Nature Conservation, Faculty of Biology, The University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland
| | - Magdalena Dudek
- Department of Plant Taxonomy and Nature Conservation, Faculty of Biology, The University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland
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Gintoron CS, Mohammed MA, Sazali SN, Deka EQ, Ong KH, Shamsi IH, King PJH. Factors Affecting Pollination and Pollinators in Oil Palm Plantations: A Review with an Emphasis on the Elaeidobius kamerunicus Weevil (Coleoptera: Curculionidae). INSECTS 2023; 14:insects14050454. [PMID: 37233082 DOI: 10.3390/insects14050454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 05/05/2023] [Accepted: 05/06/2023] [Indexed: 05/27/2023]
Abstract
Pollination is crucial for oil palm yield, and its efficiency is influenced by multiple factors, including the effectiveness of Elaeidobius kamerunicus weevils as pollinators in Southeast Asia. Weevils transfer pollen between male and female flowers, leading to successful fertilization and fruit development, which contributes to higher oil palm yields and increased production of valuable oil. Understanding and conserving the weevil population is important for sustainable oil palm cultivation practices. The interaction between pollinators, including weevils, and environmental factors is complex, involving aspects such as pollinator behavior, abundance, diversity, and effectiveness, which are influenced by weather, landscape composition, and pesticide use. Understanding these interactions is critical for promoting sustainable pollination practices, including effective pest management and maintaining optimal pollinator populations. This review discusses various abiotic and biotic factors that affect pollination and pollinators in oil palm plantations, with a particular focus on weevils as primary pollinators. Factors such as rainfall, humidity, oil palm species, temperature, endogamy, parasitic nematodes, insecticides, predators, and proximity to natural forests can impact the weevil population. Further research is recommended to fill knowledge gaps and promote sustainable pollination practices in the oil palm industry.
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Affiliation(s)
- Christharina S Gintoron
- Faculty of Agricultural and Forestry Sciences, Universiti Putra Malaysia Bintulu Sarawak, Jalan Nyabau, Bintulu 97008, Sarawak, Malaysia
- Institute Ecosystem Science Borneo, Universiti Putra Malaysia Bintulu Sarawak, Jalan Nyabau, Bintulu 97008, Sarawak, Malaysia
- Center for Pre-University Studies, Universiti Malaysia Sarawak, Kota Samarahan 94300, Sarawak, Malaysia
| | - Muhamad Azmi Mohammed
- Faculty of Agricultural and Forestry Sciences, Universiti Putra Malaysia Bintulu Sarawak, Jalan Nyabau, Bintulu 97008, Sarawak, Malaysia
| | - Siti Nurlydia Sazali
- Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, Kota Samarahan 94300, Sarawak, Malaysia
| | - Elvy Quatrin Deka
- Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, Kota Samarahan 94300, Sarawak, Malaysia
| | - Kian Huat Ong
- Faculty of Agricultural and Forestry Sciences, Universiti Putra Malaysia Bintulu Sarawak, Jalan Nyabau, Bintulu 97008, Sarawak, Malaysia
| | - Imran Haider Shamsi
- Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Patricia Jie Hung King
- Faculty of Agricultural and Forestry Sciences, Universiti Putra Malaysia Bintulu Sarawak, Jalan Nyabau, Bintulu 97008, Sarawak, Malaysia
- Institute Ecosystem Science Borneo, Universiti Putra Malaysia Bintulu Sarawak, Jalan Nyabau, Bintulu 97008, Sarawak, Malaysia
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Milet-Pinheiro P, Pinto CE, Navarro DMAF, Silva JBF, Brandt K, Ayasse M. Floral Scent Chemistry and Pollinators of a Sexually Dimorphic Neotropical Orchid. PLANTS (BASEL, SWITZERLAND) 2022; 12:17. [PMID: 36616146 PMCID: PMC9824664 DOI: 10.3390/plants12010017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 12/08/2022] [Accepted: 12/16/2022] [Indexed: 06/17/2023]
Abstract
Catasetum is a speciose Neotropical orchid genus of which male and female flowers emit scents acting both as attractant and reward for their exclusive pollinators, male orchid bees (Euglossini: Apidae). In Catasetum, it is well known that flowers display a remarkably morphological sexual dimorphism. However, it remains poorly investigated whether this is also true for floral scents. Here, we investigated the pollination ecology and floral scent traits (chemistry and total emission) of C. maranhense, a species endemic to the Brazilian N/NE region. Males of Euglossa securigera are the only pollinators of C. maranhense. The floral scent of C. maranhense is composed of 29 volatile compounds, with eucalyptol, indole, (E)-Methyl p-methoxycinnamate, and (Z)-Methyl p-methoxycinnamate accounting for more than 80% of the scent bouquet. No sexual dimorphism was detected in any of the traits investigated. We discuss the ecological and evolutionary significance of our findings to Catasetum species and other unisexual perfume plants.
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Affiliation(s)
- Paulo Milet-Pinheiro
- Laboratório de Interações Ecológicas e Semioquímicos, Universidade de Pernambuco, Campus Petrolina, Rodovia BR 203, Km 2, Petrolina 56328-903, Brazil
| | - Carlos E. Pinto
- Laboratório de Ecologia Química, Departmento de Química Fundamental, Universidade Federal de Pernambuco, 1235 Avenida Professor Moraes Rego, Recife 50670-901, Brazil
| | - Daniela M. A. F. Navarro
- Laboratório de Ecologia Química, Departmento de Química Fundamental, Universidade Federal de Pernambuco, 1235 Avenida Professor Moraes Rego, Recife 50670-901, Brazil
| | - João B. F. Silva
- Collaborator of the Departamento de Botânica, Goeldi Museum, Av. Magalhães Barata 376, Belém 66040-170, Brazil
| | - Katharina Brandt
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, 89081 Ulm, Germany
| | - Manfred Ayasse
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, 89081 Ulm, Germany
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6
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Auffray T, Montúfar R, Uquillas SXP, Barragán A, Pincebourde S, Gibernau M, Dangles O. Fine‐scale temporal dynamics of flower visitors sheds light on insect‐assemblage overlap between sexes in a dioecious Ecuadorian palm. Biotropica 2022. [DOI: 10.1111/btp.13182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Thomas Auffray
- Institut de Recherche pour le Développement, Centre d'Ecologie Fonctionnelle et Evolutive, UMR 5175, CNRS, Université de Montpellier, Université Paul Valéry, Montpellier, EPHE, IRD Montpellier France
| | - Rommel Montúfar
- Facultad de Ciencias Exactas y Naturales Pontificia Universidad Católica del Ecuador Quito Ecuador
| | - Santiago Xavier Palacios Uquillas
- Facultad de Ciencias Exactas y Naturales Pontificia Universidad Católica del Ecuador Quito Ecuador
- Museo de Zoología QCAZ, Laboratorio de Entomología Pontificia Universidad Católica del Ecuador Quito Ecuador
| | - Alvaro Barragán
- Museo de Zoología QCAZ, Laboratorio de Entomología Pontificia Universidad Católica del Ecuador Quito Ecuador
| | - Sylvain Pincebourde
- Institut de Recherche sur la Biologie de l'Insecte, UMR 7261, CNRS ‐ Université de Tours Tours France
| | - Marc Gibernau
- CNRS – Université de Corse, Laboratoire Sciences Pour l'Environnement, UMR 6134, Route des Sanguinaires Ajaccio France
| | - Olivier Dangles
- Institut de Recherche pour le Développement, Centre d'Ecologie Fonctionnelle et Evolutive, UMR 5175, CNRS, Université de Montpellier, Université Paul Valéry, Montpellier, EPHE, IRD Montpellier France
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7
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Eisen KE, Ma R, Raguso RA. Among- and within-population variation in morphology, rewards, and scent in a hawkmoth-pollinated plant. AMERICAN JOURNAL OF BOTANY 2022; 109:1794-1810. [PMID: 35762273 DOI: 10.1002/ajb2.16030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 05/24/2022] [Accepted: 05/25/2022] [Indexed: 06/15/2023]
Abstract
PREMISE Floral scent is a complex trait that mediates many plant-insect interactions, but our understanding of how floral scent variation evolves, either independently or in concert with other traits, remains limited. Assessing variation in floral scent at multiple levels of biological organization and comparing patterns of variation in scent to variation in other floral traits can contribute to our understanding of how scent variation evolves in nature. METHODS We used a greenhouse common garden experiment to investigate variation in floral scent at three scales-within plants, among plants, and among populations-and to determine whether scent, alone or in combination with morphology and rewards, contributes to population differentiation in Oenothera cespitosa subsp. marginata. Its range spans most of the biomes in the western United States, such that variation in both the abiotic and biotic environment could contribute to trait variation. RESULTS Multiple analytical approaches demonstrated substantial variation among and within populations in compound-specific and total floral scent measures. Overall, populations were differentiated in morphology and reward traits and in scent. Across populations, coupled patterns of variation in linalool, leucine-derived compounds, and hypanthium length are consistent with a long-tongued moth pollination syndrome. CONCLUSIONS The considerable variation in floral scent detected within populations suggests that, similar to other floral traits, variation in floral scent may have a heritable genetic component. Differences in patterns of population differentiation in floral scent and in morphology and rewards indicate that these traits may be shaped by different selective pressures.
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Affiliation(s)
- Katherine E Eisen
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, 14853, USA
- Department of Biology, Lund University, Lund, Sweden
| | - Rong Ma
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY, 14853, USA
| | - Robert A Raguso
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY, 14853, USA
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8
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Keefover-Ring K, Carlson CH, Hyden B, Azeem M, Smart LB. Genetic mapping of sexually dimorphic volatile and non-volatile floral secondary chemistry of a dioecious willow. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:6352-6366. [PMID: 35710312 DOI: 10.1093/jxb/erac260] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 06/14/2022] [Indexed: 06/15/2023]
Abstract
Secondary chemistry often differs between sexes in dioecious plant species, a pattern attributed to its possible role in the evolution and/or maintenance of dioecy. We used GC-MS to measure floral volatiles emitted from, and LC-MS to quantitate non-volatile secondary compounds contained in, female and male Salix purpurea willow catkins from an F2 family. Using the abundance of these chemicals, we then performed quantitative trait locus (QTL) mapping to locate them on the genome, identified biosynthetic candidate genes in the QTL intervals, and examined expression patterns of candidate genes using RNA-seq. Male flowers emitted more total terpenoids than females, but females produced more benzenoids. Male tissue contained greater amounts of phenolic glycosides, but females had more chalcones and flavonoids. A flavonoid pigment and a spermidine derivative were found only in males. Male catkins were almost twice the mass of females. Forty-two QTL were mapped for 25 chemical traits and catkin mass across 16 of the 19 S. purpurea chromosomes. Several candidate genes were identified, including a chalcone isomerase associated with seven compounds. A better understanding of the genetic basis of the sexually dimorphic chemistry of a dioecious species may shed light on how chemically mediated ecological interactions may have helped in the evolution and maintenance of dioecy.
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Affiliation(s)
- Ken Keefover-Ring
- Department of Botany, University of Wisconsin-Madison, Madison, WI, USA
- Department of Geography, University of Wisconsin-Madison, Madison, WI, USA
| | - Craig H Carlson
- Horticulture Section, School of Integrative Plant Science, Cornell University, Cornell AgriTech, Geneva, NY, USA
| | - Brennan Hyden
- Horticulture Section, School of Integrative Plant Science, Cornell University, Cornell AgriTech, Geneva, NY, USA
| | - Muhammad Azeem
- Department of Botany, University of Wisconsin-Madison, Madison, WI, USA
- Department of Chemistry, COMSATS University Islamabad, Abbottabad Campus, Abbottabad, Pakistan
| | - Lawrence B Smart
- Horticulture Section, School of Integrative Plant Science, Cornell University, Cornell AgriTech, Geneva, NY, USA
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Sexual Differences in Eurya loquaiana Dunn Floral Scent and How Pollinators Respond. PLANTS 2022; 11:plants11192560. [PMID: 36235425 PMCID: PMC9571124 DOI: 10.3390/plants11192560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 09/19/2022] [Accepted: 09/21/2022] [Indexed: 11/29/2022]
Abstract
Eurya plants are usually dioecious or subdioecious with small fragrant flowers. Here, we investigate the floral scent components of the subdioecious species Eurya loquaiana Dunn and how floral scent affects pollinators. Headspace solid-phase microextraction–gas chromatography–mass spectrometry (HS-SPME-GC-MS) was used to compare the floral scents of male, female, and hermaphrodite flowers. We also test whether differences in floral scent affect the foraging behaviors of pollinators and describe the flower morphological traits of the three sexes. Twenty-eight floral scent compounds were tentatively identified, and four monoterpenoids were tentatively identified as the most abundant compounds: linalool oxide (pyranoid), linalool, lilac aldehyde, and linalool oxide (furanoid). There were floral scent differences among the sex types, and male flowers were more attractive to pollinators in the wild, even when visual factors were excluded, indicating that pollinators likely distinguish sexual differences by floral scent. In the competition for pollinators, the advantage that male flowers have over female and hermaphrodite flowers can likely be accounted for the differences in floral scent and display size.
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10
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Phenology and Floral Biology of Diospyros sericea A. DC. (Ebenaceae): Inconstant Males May Be behind an Enigma of Dioecy. PLANTS 2022; 11:plants11192535. [PMID: 36235401 PMCID: PMC9572608 DOI: 10.3390/plants11192535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 09/19/2022] [Accepted: 09/23/2022] [Indexed: 11/29/2022]
Abstract
Diospyros sericea is a tree/shrub species considered dioecious and broadly distributed in Brazil. Despite its importance for niche composition in a range of ecosystems, there is little knowledge about this species, and so far no study has analyzed its sexual system. We aimed to investigate dioecy expression in D. sericea through sexual dimorphisms in its phenology and floral biology. We analyzed the phenological events over a year and studied floral biology traits (morphology, flower development, floral resource, floral attractants supply, viability of pollen, and stigma receptivity) in both male and female plants. D. sericea presents typical features of dioecious plants like well-established primary and secondary dimorphisms that contribute to its reproductive success. However, we also identified fruit development in what should be structurally male individuals. We suggest that the evolutionary pathway leading to the observed phenomenon may be the existence of subdioecious populations with “inconstant males”. Although our data prevented us from making further assumptions about the origin of this trait, the study contributes to future analyses towards unraveling the enigma of dioecy not only in D. sericea but in other Diospyros species.
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11
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Powers JM, Sakai AK, Weller SG, Campbell DR. Variation in floral volatiles across time, sexes, and populations of wind-pollinated Schiedea globosa. AMERICAN JOURNAL OF BOTANY 2022; 109:345-360. [PMID: 35192727 DOI: 10.1002/ajb2.1820] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 11/16/2021] [Accepted: 11/23/2021] [Indexed: 06/14/2023]
Abstract
PREMISE Floral scent is a key aspect of plant reproduction, but its intraspecific variation at multiple scales is poorly understood. Sexual dimorphism and temporal regulation of scent can be shaped by evolution, and interpopulation variation may be a bridge to species differences. We tested whether intraspecific chemical diversity in a wind-pollinated species where selection from biotic pollination is absent is associated with genetic divergence across the Hawaiian archipelago. METHODS Floral volatiles from females, males, and hermaphrodites of subdioecious Schiedea globosa grown in a common environment from 12 populations were sampled day and night and analyzed by gas chromatography-mass spectrometry. Variation among groups was analyzed by constrained ordination. We also examined the relationships of scent dissimilarity to geographic and genetic distance between populations. RESULTS Flowers increased total emissions at night through higher emissions of several ketones, oximes, and phenylacetaldehyde. Females emitted less total scent per flower at night but more of some aliphatic compounds than males, and males emitted more ketones and aldoximes. Scent differed among populations during day and night. Divergence in scent produced at night increased with geographic distance within 70-100 km and increased with genetic distance for males during the day and night, but not for females. CONCLUSIONS Schiedea globosa exhibits diel and sex-based variation in floral scent despite wind pollination and presumed loss of biotic pollination. In males, interpopulation scent differences are correlated with genetic differences, suggesting that scent evolved with dispersal within and across islands.
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Affiliation(s)
- John M Powers
- Department of Ecology and Evolutionary Biology, University of California, Irvine, 321 Steinhaus Hall, Irvine, California, 92697, USA
| | - Ann K Sakai
- Department of Ecology and Evolutionary Biology, University of California, Irvine, 321 Steinhaus Hall, Irvine, California, 92697, USA
| | - Stephen G Weller
- Department of Ecology and Evolutionary Biology, University of California, Irvine, 321 Steinhaus Hall, Irvine, California, 92697, USA
| | - Diane R Campbell
- Department of Ecology and Evolutionary Biology, University of California, Irvine, 321 Steinhaus Hall, Irvine, California, 92697, USA
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12
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Moquet L, Jacquemart A, Dufay M, De Cauwer I. Effects of sexual dimorphism on pollinator behaviour in a dioecious species. OIKOS 2021. [DOI: 10.1111/oik.08662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Laura Moquet
- Univ. Lille, CNRS, UMR 8198 – Evo‐Eco‐Paleo Lille France
- UMR PVBMT, CIRAD Saint Pierre La Réunion France
| | - Anne‐Laure Jacquemart
- Genetics, Reproduction and Populations Research Group, Earth and Life Inst., Univ. Catholique de Louvain Louvain‐la‐Neuve Belgium
| | - Mathilde Dufay
- Univ. Lille, CNRS, UMR 8198 – Evo‐Eco‐Paleo Lille France
- CEFE, Univ. Montpellier, CNRS, EPHE, IRD Montpellier France
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13
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Hyden B, Carlson CH, Gouker FE, Schmutz J, Barry K, Lipzen A, Sharma A, Sandor L, Tuskan GA, Feng G, Olson MS, DiFazio SP, Smart LB. Integrative genomics reveals paths to sex dimorphism in Salix purpurea L. HORTICULTURE RESEARCH 2021; 8:170. [PMID: 34333534 PMCID: PMC8325687 DOI: 10.1038/s41438-021-00606-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 05/23/2021] [Accepted: 06/01/2021] [Indexed: 05/16/2023]
Abstract
Sex dimorphism and gene expression were studied in developing catkins in 159 F2 individuals from the bioenergy crop Salix purpurea, and potential mechanisms and pathways for regulating sex development were explored. Differential expression, eQTL, bisulfite sequencing, and network analysis were used to characterize sex dimorphism, detect candidate master regulator genes, and identify pathways through which the sex determination region (SDR) may mediate sex dimorphism. Eleven genes are presented as candidates for master regulators of sex, supported by gene expression and network analyses. These include genes putatively involved in hormone signaling, epigenetic modification, and regulation of transcription. eQTL analysis revealed a suite of transcription factors and genes involved in secondary metabolism and floral development that were predicted to be under direct control of the sex determination region. Furthermore, data from bisulfite sequencing and small RNA sequencing revealed strong differences in expression between males and females that would implicate both of these processes in sex dimorphism pathways. These data indicate that the mechanism of sex determination in Salix purpurea is likely different from that observed in the related genus Populus. This further demonstrates the dynamic nature of SDRs in plants, which involves a multitude of mechanisms of sex determination and a high rate of turnover.
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Affiliation(s)
- Brennan Hyden
- Horticulture Section, School of Integrative Plant Science, Cornell University, Cornell AgriTech, Geneva, NY, USA
| | - Craig H Carlson
- Horticulture Section, School of Integrative Plant Science, Cornell University, Cornell AgriTech, Geneva, NY, USA
| | - Fred E Gouker
- Horticulture Section, School of Integrative Plant Science, Cornell University, Cornell AgriTech, Geneva, NY, USA
- Floral and Nursery Plants Research Unit, US National Arboretum, United States Department of Agriculture, Agricultural Research Service, Beltsville, MD, USA
| | - Jeremy Schmutz
- United States Department of Energy, Joint Genome Institute, Berkeley, CA, USA
- HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA
| | - Kerrie Barry
- United States Department of Energy, Joint Genome Institute, Berkeley, CA, USA
| | - Anna Lipzen
- United States Department of Energy, Joint Genome Institute, Berkeley, CA, USA
| | - Aditi Sharma
- United States Department of Energy, Joint Genome Institute, Berkeley, CA, USA
| | - Laura Sandor
- United States Department of Energy, Joint Genome Institute, Berkeley, CA, USA
| | - Gerald A Tuskan
- The Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Guanqiao Feng
- Department of Biology, Texas Tech University, Lubbock, TX, USA
| | - Matthew S Olson
- Department of Biology, Texas Tech University, Lubbock, TX, USA
| | - Stephen P DiFazio
- Department of Biology, West Virginia University, Morgantown, WV, USA
| | - Lawrence B Smart
- Horticulture Section, School of Integrative Plant Science, Cornell University, Cornell AgriTech, Geneva, NY, USA.
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14
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Milet-Pinheiro P, Santos PSC, Prieto-Benítez S, Ayasse M, Dötterl S. Differential Evolutionary History in Visual and Olfactory Floral Cues of the Bee-Pollinated Genus Campanula (Campanulaceae). PLANTS (BASEL, SWITZERLAND) 2021; 10:1356. [PMID: 34371561 PMCID: PMC8309401 DOI: 10.3390/plants10071356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 06/28/2021] [Accepted: 06/30/2021] [Indexed: 11/25/2022]
Abstract
Visual and olfactory floral signals play key roles in plant-pollinator interactions. In recent decades, studies investigating the evolution of either of these signals have increased considerably. However, there are large gaps in our understanding of whether or not these two cue modalities evolve in a concerted manner. Here, we characterized the visual (i.e., color) and olfactory (scent) floral cues in bee-pollinated Campanula species by spectrophotometric and chemical methods, respectively, with the aim of tracing their evolutionary paths. We found a species-specific pattern in color reflectance and scent chemistry. Multivariate phylogenetic statistics revealed no influence of phylogeny on floral color and scent bouquet. However, univariate phylogenetic statistics revealed a phylogenetic signal in some of the constituents of the scent bouquet. Our results suggest unequal evolutionary pathways of visual and olfactory floral cues in the genus Campanula. While the lack of phylogenetic signal on both color and scent bouquet points to external agents (e.g., pollinators, herbivores) as evolutionary drivers, the presence of phylogenetic signal in at least some floral scent constituents point to an influence of phylogeny on trait evolution. We discuss why external agents and phylogeny differently shape the evolutionary paths in floral color and scent of closely related angiosperms.
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Affiliation(s)
- Paulo Milet-Pinheiro
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein Allee, 89081 Ulm, Germany; (P.S.C.S.); (M.A.)
| | - Pablo Sandro Carvalho Santos
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein Allee, 89081 Ulm, Germany; (P.S.C.S.); (M.A.)
| | - Samuel Prieto-Benítez
- Departamento de Biología y Geología, Física y Química Inorgánica, Universidad Rey Juan Carlos-ESCET, C/Tulipán, s/n, Móstoles, 28933 Madrid, Spain;
- Ecotoxicology of Air Pollution Group, Environmental Department, CIEMAT, Avda. Complutense, 40, 28040 Madrid, Spain
| | - Manfred Ayasse
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein Allee, 89081 Ulm, Germany; (P.S.C.S.); (M.A.)
| | - Stefan Dötterl
- Department of Biosciences, Paris-Lodron-University of Salzburg, Hellbrunnerstrasse 34, 5020 Salzburg, Austria;
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15
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Floral scent is different between sexual phases within individuals in a synchronously dichogamous shrub (Canella winterana) but there is no distinct female or male scent profile across individuals. BIOCHEM SYST ECOL 2021. [DOI: 10.1016/j.bse.2021.104270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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16
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Maia ACD, do Amaral Ferraz Navarro DM, Núñez-Avellaneda LA, Carreño-Barrera J, Iannuzzi L, Cardona-Duque J, Nantes WAG. Methyl acetate, a highly volatile floral semiochemical mediating specialized plant-beetle interactions. Naturwissenschaften 2021; 108:21. [PMID: 33934251 DOI: 10.1007/s00114-021-01731-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 03/20/2021] [Accepted: 03/31/2021] [Indexed: 11/28/2022]
Abstract
Olfactory signaling is key to the reproductive biology of entomophilous palms. Both pollinating and specialized herbivorous insects are attracted to fragrance-emitting palm inflorescences that function as reliable food sources, as well as mating and oviposition sites. In the present study, we characterized the floral scent chemistry of the acuri palm (Attalea phalerata), assessing its role in the attraction of flower-visiting insects associated with this species over its natural distribution range. We sampled insects from staminate inflorescences of A. phalerata (n = 6) at four different sites in the Brazilian Atlantic Forest and Cerrado, and Colombian Amazon basin. Dynamic headspace scent samples of both pistillate and staminate inflorescences of A. phalerata (n = 3♀, 3♂) were collected and analyzed by gas chromatography-mass spectrometry. Methyl acetate, a rare floral scent compound, was identified as the almost exclusive constituent (> 99.8% relative percentage) in all the samples. Flight-interception traps baited with methyl acetate, installed in one of the sites in the Brazilian Cerrado, were attractive to beetles associated with inflorescences of A. phalerata across all four sampling sites (9 spp. in total), including the putative main pollinators (Mystrops spp., Nitidulidae; Andranthobius spp., Curculionidae) and various palm borers (Paratenthras martinsi, Cerambycidae; Parisoschoenus sp.1 and Belopoeus sp.1; Curculionidae). Methyl acetate is highly volatile and we hypothesize its efficacy relies on profuse emission by the inflorescences of A. phalerata, as specialized pollinating insects respond to high concentrations of the attractant, perhaps before odor plumes rapidly disperse. Such a strategy could prove particularly effective in dense populations of A. phalerata.
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Affiliation(s)
- Artur Campos D Maia
- Department of Systematics and Ecology, Universidade Federal da Paraíba, João Pessoa, 58051-900, Brazil.
| | | | | | - Javier Carreño-Barrera
- Genetic Resources Center, Instituto Agronômico de Campinas (IAC), Campinas, 13020-902, Brazil
| | - Luciana Iannuzzi
- Department of Zoology, Universidade Federal de Pernambuco, Recife, 50670-901, Brazil
| | - Juliana Cardona-Duque
- Grupo Biología CES, Facultad de Ciencias y Biotecnología, Universidad CES, 050021, Medellín, Colombia
| | - Wesley Arruda Gimenes Nantes
- Programa de Pós-Graduação em Ciências Ambientais e Sustentabilidade Agropecuária, Universidade Católica Dom Bosco, Campo Grande, 79117-900, Brazil
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17
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Simon SJ, Keefover‐Ring K, Park Y, Wimp G, Grady J, DiFazio SP. Characterization of Salix nigra floral insect community and activity of three native Andrena bees. Ecol Evol 2021; 11:4688-4700. [PMID: 33976840 PMCID: PMC8093708 DOI: 10.1002/ece3.7369] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 12/14/2020] [Accepted: 01/13/2021] [Indexed: 11/21/2022] Open
Abstract
Salix nigra (black willow) is a widespread tree that hosts many species of polylectic hymenopterans and oligolectic bees of the genus Andrena. The early flowering of S. nigra makes it an important nutritive resource for arthropods emerging from hibernation. However, since S. nigra is dioecious, not all insect visits will lead to successful pollination. Using both visual observation and pan-trapping, we characterized the community of arthropods that visited S. nigra flowers and assessed differences among male and female trees as well as the chemical and visual drivers that influenced community composition across 3 years. We found that male trees consistently supported higher diversity of insects than female trees and only three insect species, all Andrena spp., consistently visited both sexes. Additionally, Andrena nigrae, which was the only insect that occurred more on female than male flowers, correlated strongly to volatile cues. This suggests that cross-pollinators cue into specific aspects of floral scent, but diversity of floral visitors is driven strongly by visual cues of yellow male pollen. Through time, the floral activity of two Andrena species remained stable, but A. nigrae visited less in 2017 when flowers bloomed earlier than other years. When native bee emergence does not synchronize with bloom, activity appears to be diminished which could threaten species that subsist on a single host. Despite the community diversity of S. nigra flowers, its productivity depends on a small fraction of species that are not threatened by competition, but rather rapidly changing conditions that lead to host-insect asynchrony.
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Affiliation(s)
- Sandra J. Simon
- Department of BiologyWest Virginia UniversityMorgantownWVUSA
| | - Ken Keefover‐Ring
- Departments of Botany and GeographyUniversity of Wisconsin‐MadisonMadisonWIUSA
| | - Yong‐Lak Park
- Division of Plant & Soil SciencesWest Virginia UniversityMorgantownWVUSA
| | - Gina Wimp
- Department of BiologyGeorgetown UniversityWashingtonDCUSA
| | - Julianne Grady
- Department of BiologyWest Virginia UniversityMorgantownWVUSA
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18
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Essenberg CJ. Intraspecific relationships between floral signals and rewards with implications for plant fitness. AOB PLANTS 2021; 13:plab006. [PMID: 33708371 PMCID: PMC7937183 DOI: 10.1093/aobpla/plab006] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Accepted: 01/11/2021] [Indexed: 06/12/2023]
Abstract
Within-species variation in traits such as petal size or colour often provides reliable information to pollinators about the rewards offered to them by flowers. In spite of potential disadvantages of allowing pollinators to discriminate against less-rewarding flowers, examples of informative floral signals are diverse in form and widely distributed across plant taxa, apparently having evolved repeatedly in different lineages. Although hypotheses about the adaptive value of providing reward information have been proposed and tested in a few cases, a unified effort to understand the evolutionary mechanisms favouring informative floral signals has yet to emerge. This review describes the diversity of ways in which floral signals can be linked with floral rewards within plant species and discusses the constraints and selective pressures on floral signal-reward relationships. It focuses particularly on how information about floral rewards can influence pollinator behaviour and how those behavioural changes may, in turn, affect plant fitness, selecting either for providing or withholding reward information. Most of the hypotheses about the evolution of floral signal-reward relationships are, as yet, untested, and the review identifies promising research directions for addressing these considerable gaps in knowledge. The advantages and disadvantages of sharing floral reward information with pollinators likely play an important role in floral trait evolution, and opportunities abound to further our understanding of this neglected aspect of floral signalling.
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19
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Barbosa CM, Maia ACD, Martel C, Regueira JCS, Navarro DMDAF, Raguso RA, Milet-Pinheiro P, Machado IC. Reproductive biology of Syagrus coronata (Arecaceae): sex-biased insect visitation and the unusual case of scent emission by peduncular bracts. PLANT BIOLOGY (STUTTGART, GERMANY) 2021; 23:100-110. [PMID: 32757308 DOI: 10.1111/plb.13162] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Accepted: 07/16/2020] [Indexed: 06/11/2023]
Abstract
Several monoecious species of palms have developed complex strategies to promote cross-pollination, including the production of large quantities of floral resources and the emission of scents that are attractive to pollinators. Syagrus coronata constitutes an interesting model with which to understand the evolution of plant reproductive strategies in a monoecious species adapted to seasonally dry forests. We monitored blooming phenology over 1 year, during which we also collected and identified floral visitors and putative pollinators. We identified potential floral visitor attractants by characterizing the scent composition of inflorescences as well as of peduncular bracts, during both male and female phases, and the potential for floral thermogenesis. Syagrus coronata produces floral resources throughout the year. Its inflorescences are predominantly visited by a diverse assortment of small-sized beetles, whose richness and abundance vary throughout the different phases of anthesis. We did not find evidence of floral thermogenesis. A total of 23 volatile compounds were identified in the scent emitted by the inflorescences, which did not differ between male and female phases; whereas the scent of the peduncular bracts was composed of only 4-methyl guaiacol, which was absent in inflorescences. The composition of floral scent chemistry indicates that this palm has evolved strategies to be predominantly pollinated by small-sized weevils. Our study provides rare evidence of a non-floral scent emitting structure involved in pollinator attraction, only the second such case specifically in palms. The peculiarities of the reproductive strategy of S. coronata might play an important role in the maintenance of pollination services and pollen dispersion.
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Affiliation(s)
- C M Barbosa
- Departament of Botany, Programa de Pós-Graduação em Biologia Vegetal, Universidade Federal de Pernambuco, Recife, Brazil
| | - A C D Maia
- Departament of Systematics and Ecology, Universidade Federal da Paraíba, João Pessoa, Brazil
| | - C Martel
- Instituto de Ciencias Ómicas y Biotecnología Aplicada, Pontificia Universidad Católica del Perú, Av. Universitaria 1801, San Miguel 15088, Lima, Peru
| | - J C S Regueira
- Department of Zoology, Laboratório de Taxonomia e Ecologia de Insetos, Universidade Federal de Pernambuco, Recife, Brazil
| | - D M do A F Navarro
- Department of Fundamental Chemistry, Universidade Federal de Pernambuco, Recife, Brazil
| | - R A Raguso
- Department of Neurobiology and Behavior, Cornell University, Ithaca, New York, USA
| | - P Milet-Pinheiro
- Departament of Botany, Programa de Pós-Graduação em Biologia Vegetal, Universidade Federal de Pernambuco, Recife, Brazil
| | - I C Machado
- Departament of Botany, Programa de Pós-Graduação em Biologia Vegetal, Universidade Federal de Pernambuco, Recife, Brazil
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20
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Sowndhararajan K, Kim JH, Song JE, Kim M, Kim S. Chemical components of male and female flowers of Schisandra chinensis. BIOCHEM SYST ECOL 2020. [DOI: 10.1016/j.bse.2020.104121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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21
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Moquet L, Lateur L, Jacquemart AL, De Cauwer I, Dufay M. Temporal dynamics of sexual dimorphism in a dioecious species. ANNALS OF BOTANY 2020; 126:471-480. [PMID: 32386315 PMCID: PMC7424764 DOI: 10.1093/aob/mcaa088] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 05/04/2020] [Indexed: 06/01/2023]
Abstract
BACKGROUND AND AIMS Sexual dimorphism for floral traits is common in dioecious plant species. Beyond its significance for understanding how selection acts on plant traits through male vs. female reproductive function, sexual dimorphism has also been proposed as a possible risky characteristic for insect-pollinated plants, as it could drive pollinators to forage mostly on male plants. However, even though most flowering plant species spread their flowering across several weeks or months, the temporal variation of floral phenotypes and sexual dimorphism have rarely been investigated. METHODS We performed a survey of male and female plants from the dioecious generalist-pollinated Silene dioica (Caryophyllaceae) in a common garden experiment, over two consecutive flowering seasons. Flower number and floral size were measured each week, as well as pollen quantity and viability in male plants. KEY RESULTS Sexual dimorphism was found for all investigated floral traits, with males showing an overall higher investment in flower production and flower size. Males and females showed a similar temporal decline in flower size. The temporal dynamics of daily flower number differed between sexes, with males showing a peak in the middle of their flowering season, whereas flower production by females was quite stable over time. At the scale of the experimental population, both individual and floral sex ratios appeared to vary across the flowering season. Moreover, because the onset of flowering varied among plants, the magnitude of sexual dimorphism in floral size also fluctuated strongly through time. CONCLUSIONS Capturing male/female differences with only one temporal measurement per population may not be informative. This opens stimulating questions about how pollinator behaviour and resulting pollination efficiency may vary across the flowering season.
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Affiliation(s)
- L Moquet
- Univ. Lille, CNRS, Lille, France
- UMR PVBMT, Saint Pierre, La Réunion, France
- UCLouvain, Earth and Life Institute, Louvain-la-Neuve, Belgium
| | - L Lateur
- Univ. Lille, CNRS, Lille, France
| | - A-L Jacquemart
- UCLouvain, Earth and Life Institute, Louvain-la-Neuve, Belgium
| | | | - M Dufay
- Univ. Lille, CNRS, Lille, France
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Univ Paul Valery Montpellier, Montpellier, France
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22
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Yousefi M, Mohd Rafie AS, Abd Aziz S, Azrad S, ABD Razak AB. Introduction of current pollination techniques and factors affecting pollination effectiveness by Elaeidobius kamerunicus in oil palm plantations on regional and global scale: A review. SOUTH AFRICAN JOURNAL OF BOTANY 2020; 132:171-179. [DOI: 10.1016/j.sajb.2020.04.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
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23
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Dimorphic flowers modify the visitation order of pollinators from male to female flowers. Sci Rep 2020; 10:9965. [PMID: 32561882 PMCID: PMC7305190 DOI: 10.1038/s41598-020-66525-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Accepted: 05/21/2020] [Indexed: 12/11/2022] Open
Abstract
Sexual dimorphism is a pervasive form of variation within species. Understanding how and why sexual dimorphism evolves would contribute to elucidating the mechanisms underlying the diversification of traits. In flowering plants, pollinators are considered a driver of sexual dimorphism when they affect female and male plant fitness in distinct ways. Here, we found that flowers appear to manipulate the behavior of pollinators using sexually dimorphic traits in the dioecious tree Eurya japonica. In this plant, female flowers present a higher-quality reward for pollinators, whereas male flowers have a more conspicuous appearance. Plants benefit by inducing pollinators to carry pollen from male to female flowers, and their sexual dimorphism might thus facilitate pollen movement through pollinator behavior. In two-choice experiments, pollinators frequently moved from male to female flowers, whereas computer simulation suggested that sexually dimorphic traits would evolve if pollinators changed behavior depending on the traits of the flowers they had just visited. These results suggest that the floral traits affecting the visiting order of pollinators have evolved in plants. Using E. japonica, we theoretically show that the induction of sequential behavior in pollinators might be crucial to the evolution of sexual dimorphism in flowers, and our experiments support these findings.
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24
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Song JH, Hong SP. Identity and localization of floral scent components in an androdioecious species, Chionanthus retusus (Oleaceae). JOURNAL OF ASIA-PACIFIC BIODIVERSITY 2020. [DOI: 10.1016/j.japb.2020.02.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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25
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Jacquemart AL, Buyens C, Hérent MF, Quetin-Leclercq J, Lognay G, Hance T, Quinet M. Male flowers of Aconitum compensate for toxic pollen with increased floral signals and rewards for pollinators. Sci Rep 2019; 9:16498. [PMID: 31712605 PMCID: PMC6848206 DOI: 10.1038/s41598-019-53355-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 10/26/2019] [Indexed: 01/25/2023] Open
Abstract
Many plants require animal pollinators for successful reproduction; these plants provide pollinator resources in pollen and nectar (rewards) and attract pollinators by specific cues (signals). In a seeming contradiction, some plants produce toxins such as alkaloids in their pollen and nectar, protecting their resources from ineffective pollinators. We investigated signals and rewards in the toxic, protandrous bee-pollinated plant Aconitum napellus, hypothesizing that male-phase flower reproductive success is pollinator-limited, which should favour higher levels of signals (odours) and rewards (nectar and pollen) compared with female-phase flowers. Furthermore, we expected insect visitors to forage only for nectar, due to the toxicity of pollen. We demonstrated that male-phase flowers emitted more volatile molecules and produced higher volumes of nectar than female-phase flowers. Alkaloids in pollen functioned as chemical defences, and were more diverse and more concentrated compared to the alkaloids in nectar. Visitors actively collected little pollen for larval food but consumed more of the less-toxic nectar. Toxic pollen remaining on the bee bodies promoted pollen transfer efficiency, facilitating pollination.
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Affiliation(s)
- A-L Jacquemart
- Earth and Life Institute- Agronomy - Université catholique de Louvain, Croix du Sud 2, Box L7.05.14, B-1348, Louvain-la-Neuve, Belgium.
| | - C Buyens
- Earth and Life Institute- Agronomy - Université catholique de Louvain, Croix du Sud 2, Box L7.05.14, B-1348, Louvain-la-Neuve, Belgium
| | - M-F Hérent
- Louvain Drug Research Institute, Pharmacognosy Research Group - Université catholique de Louvain, Avenue E. Mounier, 72, B-1200, Brussels, Belgium
| | - J Quetin-Leclercq
- Louvain Drug Research Institute, Pharmacognosy Research Group - Université catholique de Louvain, Avenue E. Mounier, 72, B-1200, Brussels, Belgium
| | - G Lognay
- Analytical Chemistry, Gembloux Agro-Bio Tech, Université de Liège, Passage des Déportés 2, B-5030, Gembloux, Belgium
| | - T Hance
- Earth and Life Institute - Biodiversity - Université catholique de Louvain, Croix du Sud 4, Box L7.07.04, B-1348, Louvain-la-Neuve, Belgium
| | - M Quinet
- Earth and Life Institute- Agronomy - Université catholique de Louvain, Croix du Sud 2, Box L7.05.14, B-1348, Louvain-la-Neuve, Belgium
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Rebolleda-Gómez M, Forrester NJ, Russell AL, Wei N, Fetters AM, Stephens JD, Ashman TL. Gazing into the anthosphere: considering how microbes influence floral evolution. THE NEW PHYTOLOGIST 2019; 224:1012-1020. [PMID: 31442301 DOI: 10.1111/nph.16137] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 08/13/2019] [Indexed: 06/10/2023]
Abstract
The flower is the hallmark of angiosperms and its evolution is key to their diversification. As knowledge of ecological interactions between flowers and their microbial communities (the anthosphere) expands, it becomes increasingly important to consider the evolutionary impacts of these associations and their potential eco-evolutionary dynamics. In this Viewpoint we synthesize current knowledge of the anthosphere within a multilevel selection framework and illustrate the potential for the extended floral phenotype (the phenotype expressed from the genes of the plant and its associated flower microbes) to evolve. We argue that flower microbes are an important, but understudied, axis of variation that shape floral trait evolution and angiosperm reproductive ecology. We highlight knowledge gaps and discuss approaches that are critical for gaining a deeper understanding of the role microbes play in mediating plant reproduction, ecology, and evolution.
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Affiliation(s)
- María Rebolleda-Gómez
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15260, USA
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, 06520, USA
| | - Nicole J Forrester
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Avery L Russell
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Na Wei
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Andrea M Fetters
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Jessica D Stephens
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Tia-Lynn Ashman
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15260, USA
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27
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Moreira X, Nell CS, Meza-Lopez MM, Rasmann S, Mooney KA. Specificity of plant-plant communication for Baccharis salicifolia sexes but not genotypes. Ecology 2019; 99:2731-2739. [PMID: 30508249 DOI: 10.1002/ecy.2534] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 08/28/2018] [Accepted: 10/02/2018] [Indexed: 11/07/2022]
Abstract
Plants are able to adjust their anti-herbivore defenses in response to the volatile organic compounds (VOCs) emitted by herbivore-damaged neighbors, and some of these changes increase resistance against subsequent herbivory. This phenomenon of plant-plant communication is thought to be widespread, but recent investigations have cautioned that it can be context dependent, including variation in the strength of communication based on the identity of plants and their associated herbivores. Here, we performed three greenhouse experiments using multiple male and female genotypes of the dioecious woody shrub Baccharis salicifolia and its specialist aphid Uroleucon macolai to test for specificity of plant-plant communication with respect to plant sex and genotype. Moreover, we evaluated plant sexual dimorphism and genotypic variation in VOC emissions (i.e., the "speaking" side of the interaction) and response of plants to VOC exposure (i.e., the "listening" side of the interaction) in order to identify the chemical mechanisms underlying such specificity. We did not find genotypic specificity of communication; emitter plants damaged by U. macolai significantly reduced subsequent U. macolai performance on receivers, but these effects were indistinguishable for communication within vs. among genotypes. In contrast, we found sex specificity of communication; male emitter plants reduced subsequent U. macolai performance on male and female receiver plants equally, while female emitter plants only did so for female receivers. We found sexual (but not genotypic) dimorphism in speaking but not listening; of the seven compounds induced by U. macolai feeding (speaking), pinocarvone was approximately fivefold greater in female than in male plants, while exposure of plants to pinocarvone emissions (listening) reduced U. macolai performance equally in both male and female plants. Together, our study demonstrates novel evidence for sexually dimorphic specificity of plant-plant communication and the chemical mechanism underlying this effect.
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Affiliation(s)
- Xoaquín Moreira
- Misión Biológica de Galicia (MBG-CSIC), Apartado 28, 36080, Pontevedra, Galicia, Spain
| | - Colleen S Nell
- Department of Ecology and Evolutionary Biology, University of California, Irvine, 92697, California, USA
| | - Maria M Meza-Lopez
- Department of Ecology and Evolutionary Biology, University of California, Irvine, 92697, California, USA
| | - Sergio Rasmann
- Institute of Biology, Laboratory of Functional Ecology, University of Neuchâtel, Rue Emile-Argand 11, 2000, Neuchâtel, Switzerland
| | - Kailen A Mooney
- Department of Ecology and Evolutionary Biology, University of California, Irvine, 92697, California, USA
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28
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Obi Johnson B, Golonka AM, Blackwell A, Vazquez I, Wolfram N. Floral Scent Variation in the Heterostylous Species Gelsemium sempervirens. Molecules 2019; 24:molecules24152818. [PMID: 31382381 PMCID: PMC6695955 DOI: 10.3390/molecules24152818] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 07/30/2019] [Accepted: 08/01/2019] [Indexed: 11/24/2022] Open
Abstract
Gelsemium sempervirens (L.) W.T. Aiton, a distylous woody vine of the family Gelsemiaceae, produces sweetly fragrant flowers that are known for the toxic alkaloids they contain. The composition of this plant’s floral scent has not previously been determined. In this study, the scent profiles of 74 flowers obtained from six different wild and cultivated populations of G. sempervirens were measured by solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). There were 81 volatile organic compounds identified and characterized as benzenoids, terpenoids, fatty acid derivatives, and yeast associated compounds. The most abundant compound was benzaldehyde (23–80%) followed by ethanol (0.9–17%), benzyl benzoate (2–15%), 4-anisaldehyde (2–11%), (Z)-α-ocimene (0–34%), and α-farnesene (0.1–16%). The impacts of geographic location, population type (wild or cultivated), and style morph (L = long, S = short) on scent profile were investigated. The results showed no relationship between geographic location or population type and volatile organic compounds (VOC) profile, but did show a significant scent profile difference between L and S morphs based on non-metric multidimensional scaling (NMDS) using Bray-Curtis similarity indices. The L morphs contained higher amounts of benzenoids and the S morphs contained higher amounts of terpenoids in their scent profiles. The L morphs also produced a higher total abundance of scent compounds than the S morphs. This study represents the first floral scent determination of G. sempervirens finding significant variation in scent abundance and composition between style morphs.
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Affiliation(s)
- Bettie Obi Johnson
- Division of Math, Science, Nursing, and Public Health, University of South Carolina Lancaster, 476 Hubbard Drive, Lancaster, SC 29720, USA.
| | - Annette M Golonka
- Division of Math, Science, Nursing, and Public Health, University of South Carolina Lancaster, 476 Hubbard Drive, Lancaster, SC 29720, USA
| | - Austin Blackwell
- Division of Math, Science, Nursing, and Public Health, University of South Carolina Lancaster, 476 Hubbard Drive, Lancaster, SC 29720, USA
| | - Iver Vazquez
- Division of Math, Science, Nursing, and Public Health, University of South Carolina Lancaster, 476 Hubbard Drive, Lancaster, SC 29720, USA
| | - Nigel Wolfram
- Division of Math, Science, Nursing, and Public Health, University of South Carolina Lancaster, 476 Hubbard Drive, Lancaster, SC 29720, USA
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Paiva EAS, Dötterl S, De-Paula OC, Schlindwein C, Souto LS, Vitarelli NC, da Silva CI, Mateus S, Alves-Dos-Santos I, Oliveira DMT. Osmophores of Caryocar brasiliense (Caryocaraceae): a particular structure of the androecium that releases an unusual scent. PROTOPLASMA 2019; 256:971-981. [PMID: 30796515 DOI: 10.1007/s00709-019-01356-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 02/11/2019] [Indexed: 06/09/2023]
Abstract
Caryocar brasiliense is a flagship species of the Brazilian Cerrado. It produces flowers with a strong peculiar scent, which are pollinated by bats and occasionally moths with short mouthparts. However, the cues responsible for attracting these nocturnal pollinators remain unknown. We aimed to identify osmophores of C. brasiliense, describe the ultrastructure of the cells involved in the synthesis and release of floral odour, and identify the constituents of the floral bouquet. We performed field observations and histochemical and ultrastructural analyses of flowers focusing on the androecium. Gas chromatography-mass spectrometry was used to analyse the scents emitted. Filament epidermal cells were found to possess an unusual shape and be responsible for the main production and release of odour. These cells, called foraminous cells, are elongate and possess pores where their cell walls are abruptly thin. The cuticle is practically absent over the pores, which facilitates odour emission. The foraminous cells have conspicuous nuclei and organelle-rich cytoplasm where oil droplets can be seen prior to anthesis. The features of these cells remain similar during anthesis, but many vesicles fuse with the plasma membrane and the number of oil droplets in the cytosol decreases. Twenty-nine components were found in the scent, especially fatty acid derivatives and N- and S-bearing compounds. Our analyses revealed that the androecium of C. brasiliense has a particular structure that acts as an osmophore. The scent from the androecium resembles that of the entire flower, which is an unprecedented finding for a plant with single flowers as the pollination unit.
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Affiliation(s)
- Elder Antônio Sousa Paiva
- Departamento de Botânica, ICB, Universidade Federal de Minas Gerais, Caixa Postal 486, Belo Horizonte, MG, 31270-901, Brazil.
| | - Stefan Dötterl
- Department of Biosciences, Plant Ecology, University of Salzburg, Hellbrunnerstr. 34, 5020, Salzburg, Austria
| | | | - Clemens Schlindwein
- Departamento de Botânica, ICB, Universidade Federal de Minas Gerais, Caixa Postal 486, Belo Horizonte, MG, 31270-901, Brazil
| | - Letícia Silva Souto
- Departamento de Biologia, CCHB, Universidade Federal de São Carlos, Campus Sorocaba, Sorocaba, SP, 18052-780, Brazil
| | - Narah Costa Vitarelli
- Departamento de Educação e Ciências, Núcleo de Biologia, Instituto Federal de Ciências e Tecnologia do Sudeste de Minas Gerais (IFSUDESTEMG, Campus Juiz de Fora), Rua Bernardo Mascarenhas, 1283 - Bairro Fábrica, Juiz de Fora, MG, Brazil
| | - Claudia Inês da Silva
- Departamento de Ecologia, IBUSP, Universidade de São Paulo, São Paulo, SP, 05508-900, Brazil
| | - Sidnei Mateus
- Departamento de Biologia, FFCLRP, Universidade de São Paulo, Ribeirão Preto, SP, 14040-900, Brazil
| | - Isabel Alves-Dos-Santos
- Departamento de Ecologia, IBUSP, Universidade de São Paulo, São Paulo, SP, 05508-900, Brazil
| | - Denise Maria Trombert Oliveira
- Departamento de Botânica, ICB, Universidade Federal de Minas Gerais, Caixa Postal 486, Belo Horizonte, MG, 31270-901, Brazil
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Moreira X, Abdala-Roberts L. Specificity and context-dependency of plant-plant communication in response to insect herbivory. CURRENT OPINION IN INSECT SCIENCE 2019; 32:15-21. [PMID: 31113626 DOI: 10.1016/j.cois.2018.09.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 06/16/2018] [Accepted: 09/05/2018] [Indexed: 05/21/2023]
Abstract
Over three decades of work on airborne plant communication have taught us that plants send, receive, and respond to volatile organic compounds (VOCs) emitted by conspecific as well as heterospecific neighbouring plants. Much of this research has focused on the consequences of plant-plant communication on resistance against herbivory, with studies showing that VOCs emitted by herbivore-damaged plants increase resistance of neighbouring undamaged plants. However, a key aspect that has received less attention concerns the ecological specificity and context-dependency of this phenomenon. Knowledge on this is crucial for assessing the ecological mechanisms that govern plant communication, determining its biological significance under natural conditions, as well as designing effective strategies for its application (e.g. in crop protection). Here we synthesize important advances from incipient work on the ecological specificity of plant communication according to three main aspects: plant-based specificity, herbivore-based specificity, and the influence of the abiotic context. We then provide some ideas for future research to improve our understanding of the specificity of plant communication and its ecological and evolutionary importance.
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Affiliation(s)
- Xoaquín Moreira
- Misión Biológica de Galicia (MBG-CSIC), Apartado de Correos 28, 36080, Pontevedra, Galicia, Spain.
| | - Luis Abdala-Roberts
- Departamento de Ecología Tropical, Campus de Ciencias Biológicas y Agropecuarias, Universidad Autónoma de Yucatán, Apartado, Postal 4-116, Itzimná, 97000, Mérida, Yucatán, Mexico
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31
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Wang H, Zheng P, Aoki D, Miyake T, Yagami S, Matsushita Y, Fukushima K, Nakagawa M. Sexual and temporal variations in floral scent in the subdioecious shrub Eurya japonica Thunb. Ecol Evol 2018; 8:8266-8272. [PMID: 30250701 PMCID: PMC6144988 DOI: 10.1002/ece3.4378] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Revised: 05/22/2018] [Accepted: 06/27/2018] [Indexed: 11/10/2022] Open
Abstract
In many flowering plants, floral scents are a significant trait for visitors, playing an important role in attracting pollinators and/or detracting herbivores. The evolution of flowering plants from hermaphroditism to dioecy is often accompanied by sexual dimorphism in floral scent. In this study, floral scents emitted by different sexual morphs of the subdioecious shrub Eurya japonica Thunb. were collected using a dynamic headspace method, and sexual and temporal variations were evaluated by gas chromatography-mass spectrometry (GC-MS). Two volatiles, α-pinene and linalool, were identified as the major components of floral scents in females, hermaphrodites, and males. The males emit higher amounts of floral scents, particularly α-pinene, compared to females or hermaphrodites. Floral scents emitted by males generally decrease as flowers enter senescence, whereas those from females or hermaphrodites do not significantly differ. Intraspecific variations in floral scents of subdioecious species provided by this study would contribute to better understanding of sexual dimorphism in floral scent.
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Affiliation(s)
- Hui Wang
- School of Life ScienceShandong UniversityJinanChina
- Graduate School of Bioagricultural SciencesNagoya UniversityNagoyaJapan
| | - Peiming Zheng
- School of Life ScienceShandong UniversityJinanChina
- Graduate School of Bioagricultural SciencesNagoya UniversityNagoyaJapan
- Structural Materials Research InstituteNational Institute of Advanced Industrial Science and TechnologyNagoyaJapan
| | - Dan Aoki
- Graduate School of Bioagricultural SciencesNagoya UniversityNagoyaJapan
| | | | - Sachie Yagami
- Graduate School of Bioagricultural SciencesNagoya UniversityNagoyaJapan
| | | | | | - Michiko Nakagawa
- Graduate School of Bioagricultural SciencesNagoya UniversityNagoyaJapan
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Suinyuy TN, Johnson SD. Geographic variation in cone volatiles and pollinators in the thermogenic African cycad Encephalartos ghellinckii Lem. PLANT BIOLOGY (STUTTGART, GERMANY) 2018; 20:579-590. [PMID: 29281847 DOI: 10.1111/plb.12685] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 12/19/2017] [Indexed: 06/07/2023]
Abstract
Heat and odour production can have profound effects on pollination in cycads. It is therefore expected that these traits would co-vary geographically with pollinator assemblages. Such intraspecific variation, may lead to the evolution of pollination ecotypes, which can be an early stage of pollinator-mediated speciation. We measured cone temperatures using miniature temperature data loggers and examined the composition of cone volatile odours using headspace sampling and analysis with gas chromatography-mass spectrometry in four populations spanning the range of the African cycad Encephalartos ghellinckii. Pollinator assemblages were also investigated in three populations. Male and female cones were thermogenic at pollen shed and receptive stages, respectively, but patterns of thermogenesis did not vary among populations. Scent emissions from cones in populations in the Drakensberg Mountains were characterised by cis-β-ocimene, β-myrcene and (3E)-1,3-octadiene, while camphene and α-pinene were characteristic of scent emissions from cones in populations closer to the coast. These differences in volatile blends corresponded with differences in insect assemblages. These results confirm intraspecific variation in volatile emissions of E. ghellinckii and support the predictions that intraspecific variation in volatile emissions will be associated with shifts in pollinator assemblages. While further work needs to be done to test for local adaptation in this system, this preliminary evidence is consistent with the formation of pollination ecotypes in the E. ghellinckii species complex.
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Affiliation(s)
- T N Suinyuy
- School of Life Sciences, University of KwaZulu-Natal, Scottsville, Pietermaritzburg, South Africa
| | - S D Johnson
- School of Life Sciences, University of KwaZulu-Natal, Scottsville, Pietermaritzburg, South Africa
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Pérez-Barrales R, Abarca CA, Santos-Gally R, Schiestl FP, Arroyo J. The function of the floral corona in the pollination of a Mediterranean style dimorphic daffodil. PLANT BIOLOGY (STUTTGART, GERMANY) 2018; 20 Suppl 1:118-127. [PMID: 29105981 DOI: 10.1111/plb.12657] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 10/30/2017] [Indexed: 06/07/2023]
Abstract
Narcissus papyraceus is a style dimorphic species with two floral forms, with anthers at similar height and stigmas above (long-styled L) and below (short-styled S) the anther level. The species is self-incompatible, but intra- and inter-morph compatible. Populations are either dimorphic (including both morphs) in the region of the Strait of Gibraltar, or L-monomorphic (with only L plants) in the inland of the Iberian Peninsula. This variation correlates with the most common floral visitors, being primarily long-tongued and short-tongued pollinators, respectively, a rare condition in Mediterranean plants. The maintenance of S-flowers relies on long-tongued insects, as only those deliver pollen to short-styled stigmas. Narcissus flowers present a long and narrow tube, at the bottom of which nectar accumulates, and a floral corona, which has been proposed as an important trait for the attraction of pollinators. Here we tested the importance of the corona on pollination of L and S flowers. We described UV reflectance patterns of the corona and tepals, and characterised VOCs in intact flowers and flowers with trimmed coronas. We also conducted a field experiment in the dimorphic and monomorphic region to estimate the importance of corona removal on seed production in stands with solitary plants and in groups to control for compatible pollen limitation. Reflectance was higher in the tepals than the corona, although both traits presented a reflectance peak around 450 nm wavelength. L- and S-flowers produced similar volatiles, regardless of the manipulation of the corona. Across dimorphic and monomorphic regions, S-flowers with the corona removed suffered a reduction in seed production of ca. 50%, while seed production remained similar in L flowers both with the corona intact and removed. Plants in solitary stands suffered a strong reduction in seed production, which was more pronounced in the monomorphic region. Our results suggest that the corona in Narcissus is more important for the pollination of S-flowers, which generally have lower seed production compared to L-flowers. Taken together, these results suggest that the floral corona indirectly plays an important role for maintenance of the polymorphism.
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Affiliation(s)
- R Pérez-Barrales
- School of Biological Sciences, University of Portsmouth, Portsmouth, UK
| | - C A Abarca
- Unidad Lerma Departamento de Ecología Evolutiva, Departamento de Ciencias Ambientales, Universidad Autónoma Metropolitana, Mexico City, México
| | - R Santos-Gally
- CONACYT-Departamento de Ecología Evolutiva, Instituto de Ecología, UNAM, Mexico City, México
| | - F P Schiestl
- Institute of Systematic Botany, University of Zurich, Zurich, Switzerland
| | - J Arroyo
- Departamento de Biología Vegetal y Ecología, Universidad de Sevilla, Sevilla, Spain
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Delle-Vedove R, Schatz B, Dufay M. Understanding intraspecific variation of floral scent in light of evolutionary ecology. ANNALS OF BOTANY 2017; 120:1-20. [PMID: 28873948 PMCID: PMC5737645 DOI: 10.1093/aob/mcx055] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Accepted: 03/29/2017] [Indexed: 05/29/2023]
Abstract
Background and Aims Among the various floral traits involved in pollinator attraction and potentially under selection mediated by pollinators, floral scent/fragrance has been less investigated than other components of floral phenotype. Whether or not pollinator-mediated selection impacts floral scents depends on the heritability of scent/fragrance and the occurrence of some variation within species. Although most studies have investigated how scent varies among species, growing amounts of data are available on variation at the intraspecific level. Methods The results of 81 studies investigating intraspecific variation of floral scents in 132 taxa were reviewed. For each study, whether variation was found in either identity, proportion or absolute quantities of volatile organic compounds (VOCs) was recorded, as well as information with the potential to explain variation, such as methodology, plant origin or pollination biology. Key Results Variation was found for almost all investigated species, both among individuals (among and sometimes within populations) and within individuals across different temporal scales. Cases in which such variation is a possible result of pollinator-mediated selection were analysed, by discussing separately selection related to variation in pollinator identity/behaviour among populations or across time, deceit pollination and sex-specific selection. Not surprisingly, in many cases, pollinator-mediated selection alone does not explain the observed variation in floral scent. This led us to review current knowledge on less investigated factors, such as selection mediated by natural enemies, genetic drift and gene flow, environmental constraints, phylogenetic inertia, or biochemical constraints that could be invoked to explain scent variation. Conclusions This review highlights the great potential of analysing floral scent variation and including it in integrated studies of floral phenotypes. We also have identified the current gaps in our understanding of this complex signal and we propose several methodological and conceptual future directions in this research area.
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Affiliation(s)
- Roxane Delle-Vedove
- Universite de Lille, CNRS UMR 8198 Evo-Eco-Paleo, 59655 Villeneuve d'Ascq Cedex, France
| | - Bertrand Schatz
- CEFE (Centre d’Ecologie Fonctionnelle et Evolutive), UMR 5175, CNRS, Université de Montpellier, Université Paul-Valéry Montpellier, EPHE, 1919 route de Mende, 34293 Montpellier, France
| | - Mathilde Dufay
- Universite de Lille, CNRS UMR 8198 Evo-Eco-Paleo, 59655 Villeneuve d'Ascq Cedex, France
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Burkle LA, Runyon JB. The smell of environmental change: Using floral scent to explain shifts in pollinator attraction. APPLICATIONS IN PLANT SCIENCES 2017; 5:apps1600123. [PMID: 28690928 PMCID: PMC5499301 DOI: 10.3732/apps.1600123] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 01/03/2017] [Indexed: 05/18/2023]
Abstract
As diverse environmental changes continue to influence the structure and function of plant-pollinator interactions across spatial and temporal scales, we will need to enlist numerous approaches to understand these changes. Quantitative examination of floral volatile organic compounds (VOCs) is one approach that is gaining popularity, and recent work suggests that floral VOCs hold substantial promise for better understanding and predicting the effects of environmental change on plant-pollinator interactions. Until recently, few ecologists were employing chemical approaches to investigate mechanisms by which components of environmental change may disrupt these essential mutualisms. In an attempt to make these approaches more accessible, we summarize the main field, laboratory, and statistical methods involved in capturing, quantifying, and analyzing floral VOCs in the context of changing environments. We also highlight some outstanding questions that we consider to be highly relevant to making progress in this field.
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Affiliation(s)
- Laura A. Burkle
- Department of Ecology, Montana State University, Bozeman, Montana 59717 USA
- Author for correspondence:
| | - Justin B. Runyon
- Rocky Mountain Research Station, USDA Forest Service, 1648 S. 7th Avenue, Bozeman, Montana 59717 USA
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Terry LI, Roemer RB, Booth DT, Moore CJ, Walter GH. Thermogenic respiratory processes drive the exponential increase of volatile organic compound emissions in Macrozamia cycad cones. PLANT, CELL & ENVIRONMENT 2016; 39:1588-1600. [PMID: 26924274 DOI: 10.1111/pce.12730] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 02/12/2016] [Accepted: 02/14/2016] [Indexed: 06/05/2023]
Abstract
An important outcome of plant thermogenesis is increased emissions of volatiles that mediate pollinator behaviour. We investigated whether the large increase in emissions, mainly the monoterpene ß-myrcene (>90%), during daily thermogenic events of Macrozamia macleayi and lucida cycad cones are due solely to the influence of high cone temperatures or are, instead, a result of increased respiratory rates during thermogenesis. We concurrently measured temperature, oxygen consumption and ß-myrcene emission profiles during thermogenesis of pollen cones under typical environmental temperatures and during experimental manipulations of cone temperatures and aerobic conditions, all in the dark. The exponential rise in ß-myrcene emissions never occurred without a prior, large increase in respiration, whereas an increase in cone temperature alone did not increase emissions. When respiration during thermogenesis was interrupted by anoxic conditions, ß-myrcene emissions decreased. The increased emission rates are not a result of increased cone temperature per se (through increased enzyme activity or volatilization of stored volatiles) but are dependent on biosynthetic pathways associated with increased respiration during thermogenesis that provide the carbon, energy (ATP) and reducing compounds (NADPH) required for ß-myrcene production through the methylerythritol phosphate (MEP) pathway. These findings establish the significant contribution of respiration to volatile production during thermogenesis.
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Affiliation(s)
- L Irene Terry
- Department of Biology, University of Utah, 257 S. 1400 E., Salt Lake City, UT, 84112, USA
| | - Robert B Roemer
- Department of Mechanical Engineering, University of Utah, 50 S. Central Campus Dr., 2202 Merrill Engineering Bldg, Salt Lake City, UT, 84112, USA
| | - David T Booth
- School of Biological Sciences, The University of Queensland, Brisbane, 4072, Queensland, Australia
| | - Chris J Moore
- School of Biological Sciences, The University of Queensland, Brisbane, 4072, Queensland, Australia
| | - Gimme H Walter
- School of Biological Sciences, The University of Queensland, Brisbane, 4072, Queensland, Australia
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Zito P, Scrima A, Sajeva M, Carimi F, Dötterl S. Dimorphism in inflorescence scent of dioecious wild grapevine. BIOCHEM SYST ECOL 2016. [DOI: 10.1016/j.bse.2016.03.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Hossaert-McKey M, Proffit M, Soler CCL, Chen C, Bessière JM, Schatz B, Borges RM. How to be a dioecious fig: Chemical mimicry between sexes matters only when both sexes flower synchronously. Sci Rep 2016; 6:21236. [PMID: 26888579 PMCID: PMC4758059 DOI: 10.1038/srep21236] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 01/14/2016] [Indexed: 11/18/2022] Open
Abstract
In nursery pollination mutualisms, which are usually obligate interactions, olfactory attraction of pollinators by floral volatile organic compounds (VOCs) is the main step in guaranteeing partner encounter. However, mechanisms ensuring the evolutionary stability of dioecious fig-pollinator mutualisms, in which female fig trees engage in pollination by deceit resulting in zero reproductive success of pollinators that visit them, are poorly understood. In dioecious figs, individuals of each sex should be selected to produce odours that their pollinating wasps cannot distinguish, especially since pollinators have usually only one choice of a nursery during their lifetime. To test the hypothesis of intersexual chemical mimicry, VOCs emitted by pollen-receptive figs of seven dioecious species were compared using headspace collection and gas chromatography-mass spectrometry analysis. First, fig-flower scents varied significantly among species, allowing host-species recognition. Second, in species in which male and female figs are synchronous, intersexual VOC variation was not significant. However, in species where figs of both sexes flower asynchronously, intersexual variation of VOCs was detectable. Finally, with one exception, there was no sexual dimorphism in scent quantity. We show that there are two ways to use scent to be a dioecious fig based on differences in flowering synchrony between the sexes.
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Affiliation(s)
- M. Hossaert-McKey
- Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), UMR 5175, CNRS—Université de Montpellier—Université Paul Valéry Montpellier—EPHE, 1919 route de Mende, 34293 Montpellier, France
| | - M. Proffit
- Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), UMR 5175, CNRS—Université de Montpellier—Université Paul Valéry Montpellier—EPHE, 1919 route de Mende, 34293 Montpellier, France
| | - C. C. L. Soler
- Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), UMR 5175, CNRS—Université de Montpellier—Université Paul Valéry Montpellier—EPHE, 1919 route de Mende, 34293 Montpellier, France
| | - C. Chen
- Xishuangbanna Tropical Botanical Garden (XTBG); National Chinese Academy of Sciences; Menglun, Yunnan China
| | - J.-M. Bessière
- Laboratoire de Chimie Appliquée, Ecole Nationale Supérieure de Chimie de Montpellier, 8 rue de l’Ecole Normale, 34296 Montpellier Cedex 5, France
| | - B. Schatz
- Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), UMR 5175, CNRS—Université de Montpellier—Université Paul Valéry Montpellier—EPHE, 1919 route de Mende, 34293 Montpellier, France
| | - R. M. Borges
- Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560 012, India
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Welsford MR, Hobbhahn N, Midgley JJ, Johnson SD. Floral trait evolution associated with shifts between insect and wind pollination in the dioecious genusLeucadendron(Proteaceae). Evolution 2015; 70:126-39. [DOI: 10.1111/evo.12821] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 10/28/2015] [Accepted: 11/06/2015] [Indexed: 11/29/2022]
Affiliation(s)
- Megan R. Welsford
- School of Life Sciences; University of KwaZulu-Natal; P. Bag X01 Scottsville 3209 Pietermaritzburg South Africa
| | - Nina Hobbhahn
- School of Life Sciences; University of KwaZulu-Natal; P. Bag X01 Scottsville 3209 Pietermaritzburg South Africa
| | - Jeremy J. Midgley
- Department of Biological Sciences; University of Cape Town; Rondebosch 7701 South Africa
| | - Steven D. Johnson
- School of Life Sciences; University of KwaZulu-Natal; P. Bag X01 Scottsville 3209 Pietermaritzburg South Africa
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Milet-Pinheiro P, Navarro DMDAF, Dötterl S, Carvalho AT, Pinto CE, Ayasse M, Schlindwein C. Pollination biology in the dioecious orchid Catasetum uncatum: How does floral scent influence the behaviour of pollinators? PHYTOCHEMISTRY 2015; 116:149-161. [PMID: 25771507 DOI: 10.1016/j.phytochem.2015.02.027] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 02/23/2015] [Accepted: 02/25/2015] [Indexed: 06/04/2023]
Abstract
Catasetum is a neotropical orchid genus that comprises about 160 dioecious species with a remarkable sexual dimorphism in floral morphology. Flowers of Catasetum produce perfumes as rewards, which are collected only by male euglossine bees. Currently, floral scents are known to be involved in the selective attraction of specific euglossine species. However, sexual dimorphism in floral scent and its eventual role in the pollination of Catasetum species have never been investigated. Here, we have investigated the pollination of Catasetum uncatum and asked: (1) Is floral scent a sexual dimorphic trait? (2) Does pollinarium removal/deposition affect scent emission? (3) Does sexual dimorphism in floral scent and changed scent emission have implications with regard to the behaviour of the pollinators? The frequency and behaviour of floral visitors were observed in non-manipulated flowers (both flower sexes) and in manipulated flowers (pistillate only) in which pollinaria were deposited. Scents of staminate and pistillate flowers (both manipulated and non-manipulated) were collected by using dynamic headspace methods and analysed chemically. Electrophysiological analyses were performed to detect compounds triggering antennal depolarisation in the euglossine species. C. uncatum is pollinated mainly by males of Euglossa nanomelanotricha. Pollinators were more frequent in pistillate than in staminate inflorescences. Bees approaching staminate flowers frequently flew away without visiting them, a behavioural pattern not observed in pistillate flowers. In the chemical analyses, we recorded 99 compounds, 31 of which triggered antennal depolarisation in pollinators. Multivariate analyses with the electrophysiological-active compounds did not detect differences between the scent composition of staminate and pistillate flowers. Pollinarium removal or deposition resulted in diminished scent emission within 24h in staminate and pistillate flowers, respectively. Surprisingly, bees discriminated pollinated from non-pollinated pistillate flowers as early as 2h after pollination. The rapid loss in the attractiveness of flowers following pollinarium removal/deposition can be interpreted as a strategy to direct pollinators to non-pollinated flowers. We have found no evidence that euglossine males discriminate staminate from pistillate flowers by means of floral scent. Instead, we speculate that bees use visual cues, such as sex dimorphic traits, to discriminate flowers of different sexes. Together, our results provide interesting insights into the evolution of floral signals in gender-dimorphic species and into its significance in plant reproductive biology.
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Affiliation(s)
- Paulo Milet-Pinheiro
- Departamento de Química Fundamental, Universidade Federal de Pernambuco, Av. Prof. Moraes Rego, s/n, 50670-901 Recife, Brazil; Institute of Experimental Ecology, University of Ulm, Albert-Einstein-Allee 11, 89069 Ulm, Germany.
| | | | - Stefan Dötterl
- Department of Organismic Biology, University of Salzburg, Hellbrunnerstrasse 34, 5020 Salzburg, Austria
| | - Airton Torres Carvalho
- Departamento de Ciências Animais, Universidade Federal Rural do Semi-Árido, Avenida Francisco Mota 572, Mossoró, Rio Grande do Norte 59625-900, Brazil
| | - Carlos Eduardo Pinto
- Programa de Pós-Graduacão em Entomologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto-São Paulo 14040-901, Brazil
| | - Manfred Ayasse
- Institute of Experimental Ecology, University of Ulm, Albert-Einstein-Allee 11, 89069 Ulm, Germany
| | - Clemens Schlindwein
- Departamento de Botânica, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, 31270-901 Belo Horizonte, MG, Brazil
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Carr DE, Haber AI, LeCroy KA, Lee DE, Link RI. Variation in reward quality and pollinator attraction: the consumer does not always get it right. AOB PLANTS 2015; 7:plv034. [PMID: 25858692 PMCID: PMC4417137 DOI: 10.1093/aobpla/plv034] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Accepted: 03/16/2015] [Indexed: 05/29/2023]
Abstract
Nearly all bees rely on pollen as the sole protein source for the development of their larvae. The central importance of pollen for the bee life cycle should exert strong selection on their ability to locate the most rewarding sources of pollen. Despite this importance, very few studies have examined the influence of intraspecific variation in pollen rewards on the foraging decisions of bees. Previous studies have demonstrated that inbreeding reduces viability and hence protein content in Mimulus guttatus (seep monkeyflower) pollen and that bees strongly discriminate against inbred in favour of outbred plants. We examined whether variation in pollen viability could explain this preference using a series of choice tests with living plants, artificial plants and olfactometer tests using the bumble bee Bombus impatiens. We found that B. impatiens preferred to visit artificial plants provisioned with fertile anthers over those provisioned with sterile anthers. They also preferred fertile anthers when provided only olfactory cues. These bumble bees were unable to discriminate among live plants from subpopulations differing dramatically in pollen viability, however. They preferred outbred plants even when those plants were from subpopulations with pollen viability as low as the inbred populations. Their preference for outbred plants was evident even when only olfactory cues were available. Our data showed that bumble bees are able to differentiate between anthers that provide higher rewards when cues are isolated from the rest of the flower. When confronted with cues from the entire flower, their choices are independent of the quality of the pollen reward, suggesting that they are responding more strongly to cues unassociated with rewards than to those correlated with rewards. If so, this suggests that a sensory bias or some level of deception may be involved with advertisement to pollinators in M. guttatus.
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Affiliation(s)
- David E Carr
- Blandy Experimental Farm, University of Virginia, 400 Blandy Farm Lane, Boyce, VA 22620, USA
| | - Ariela I Haber
- Department of Environmental Sciences, University of Virginia, Charlottesville, VA 22904, USA
| | - Kathryn A LeCroy
- Department of Environmental Sciences, University of Virginia, Charlottesville, VA 22904, USA
| | - De'Ashia E Lee
- Department of Infectious Diseases, University of Georgia, 500 DW Brooks Drive, Athens, GA 30602, USA
| | - Rosabeth I Link
- Department of Entomology, University of Wisconsin, Madison, WI 53706, USA
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Interspecific and Intersexual Differences in the Chemical Composition of Floral Scent inGlochidionSpecies (Phyllanthaceae) in South China. J CHEM-NY 2015. [DOI: 10.1155/2015/865694] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Plants of theGlochidion(Phyllanthaceae) genus are pollinated exclusively by host-specificEpicephala(Gracillariidae) moths. Floral scent has been thought to play key role in the obligate pollination mutualism betweenGlochidionplants andEpicephalamoths, but few studies have been reported about chemical variation in floral volatiles ofGlochidionspecies in China. Floral volatiles of male and female flowers of fiveGlochidionspecies in south China were collected by dynamic headspace absorption technique and then were chemically analyzed by using gas chromatography-mass spectrometry. A total of 69 compounds were identified from floral scents of five investigated species.Glochidion hirsutumandG.zeylanicumshowed no qualitative differences in floral scent, whereas there were clear variations of floral scent among other species (G. eriocarpum,G.daltonii, andG. sphaerogynum) and also they distinctly differed from these two species. Male flowers emitted significantly more scent than female flowers.Glochidionplants exhibited qualitative and quantitative differences in floral scent between two sexes of flowers. The findings suggest that the volatile variation of floral scent amongGlochidionspecies reflects adaptations to specific pollinators. Sexual dimorphism in floral scent has evolved to signal alternative rewards provided by each sex toEpicephalamoths.
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Forrest JRK. Plant Size, Sexual Selection, and the Evolution of Protandry in Dioecious Plants. Am Nat 2014; 184:338-51. [DOI: 10.1086/677295] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Okamoto T, Kawakita A, Goto R, Svensson GP, Kato M. Active pollination favours sexual dimorphism in floral scent. Proc Biol Sci 2014; 280:20132280. [PMID: 24266037 DOI: 10.1098/rspb.2013.2280] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Zoophilous flowers often transmit olfactory signals to attract pollinators. In plants with unisexual flowers, such signals are usually similar between the sexes because attraction of the same animal to both male and female flowers is essential for conspecific pollen transfer. Here, we present a remarkable example of sexual dimorphism in floral signal observed in reproductively highly specialized clades of the tribe Phyllantheae (Phyllanthaceae). These plants are pollinated by species-specific, seed-parasitic Epicephala moths (Gracillariidae) that actively collect pollen from male flowers and pollinate the female flowers in which they oviposit; by doing so, they ensure seeds for their offspring. We found that Epicephala-pollinated Phyllanthaceae plants consistently exhibit major qualitative differences in scent between male and female flowers, often involving compounds derived from different biosynthetic pathways. In a choice test, mated female Epicephala moths preferred the scent of male flowers over that of female flowers, suggesting that male floral scent elicits pollen-collecting behaviour. Epicephala pollination evolved multiple times in Phyllantheae, at least thrice accompanied by transition from sexual monomorphism to dimorphism in floral scent. This is the first example in which sexually dimorphic floral scent has evolved to signal an alternative reward provided by each sex, provoking the pollinator's legitimate altruistic behaviour.
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Dötterl S, Glück U, Jürgens A, Woodring J, Aas G. Floral reward, advertisement and attractiveness to honey bees in dioecious Salix caprea. PLoS One 2014; 9:e93421. [PMID: 24676333 PMCID: PMC3968154 DOI: 10.1371/journal.pone.0093421] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2013] [Accepted: 03/06/2014] [Indexed: 11/21/2022] Open
Abstract
In dioecious, zoophilous plants potential pollinators have to be attracted to both sexes and switch between individuals of both sexes for pollination to occur. It often has been suggested that males and females require different numbers of visits for maximum reproductive success because male fertility is more likely limited by access to mates, whereas female fertility is rather limited by resource availability. According to sexual selection theory, males therefore should invest more in pollinator attraction (advertisement, reward) than females. However, our knowledge on the sex specific investment in floral rewards and advertisement, and its effects on pollinator behaviour is limited. Here, we use an approach that includes chemical, spectrophotometric, and behavioural studies i) to elucidate differences in floral nectar reward and advertisement (visual, olfactory cues) in dioecious sallow, Salix caprea, ii) to determine the relative importance of visual and olfactory floral cues in attracting honey bee pollinators, and iii) to test for differential attractiveness of female and male inflorescence cues to honey bees. Nectar amount and sugar concentration are comparable, but sugar composition varies between the sexes. Olfactory sallow cues are more attractive to honey bees than visual cues; however, a combination of both cues elicits the strongest behavioural responses in bees. Male flowers are due to the yellow pollen more colourful and emit a higher amount of scent than females. Honey bees prefer the visual but not the olfactory display of males over those of females. In all, the data of our multifaceted study are consistent with the sexual selection theory and provide novel insights on how the model organism honey bee uses visual and olfactory floral cues for locating host plants.
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Affiliation(s)
- Stefan Dötterl
- Department of Plant Systematics, University of Bayreuth, Bayreuth, Germany
- * E-mail:
| | - Ulrike Glück
- Ecological-Botanical Garden, University of Bayreuth, Bayreuth, Germany
| | - Andreas Jürgens
- School of Biological and Conservation Sciences, University of KwaZulu-Natal, Pietermaritzburg, South Africa
| | - Joseph Woodring
- Department of Animal Ecology, University of Bayreuth, Bayreuth, Germany
| | - Gregor Aas
- Ecological-Botanical Garden, University of Bayreuth, Bayreuth, Germany
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Suinyuy TN, Donaldson JS, Johnson SD. Variation in the chemical composition of cone volatiles within the African cycad genus Encephalartos. PHYTOCHEMISTRY 2013; 85:82-91. [PMID: 23098901 DOI: 10.1016/j.phytochem.2012.09.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 09/21/2012] [Accepted: 09/26/2012] [Indexed: 06/01/2023]
Abstract
Volatiles play a key role in attraction of pollinators to cycad cones, but the extent to which volatile chemistry varies among cycad species is still poorly documented. Volatile composition of male and female cones of nineteen African cycad species (Encephalartos; Zamiaceae) was analysed using headspace technique and gas chromatography-mass spectrometry (GC-MS). A total of 152 compounds were identified among the species included in this study, the most common of which were monoterpenes, nitrogen-containing compounds and unsaturated hydrocarbons. Male and female cones emitted similar volatile compounds which varied in relative amounts with two unsaturated hydrocarbons (3E)-1,3-octadiene and (3E,5Z)-1,3,5-octatriene present in the volatile profile of most species. In a multivariate analysis of volatile profiles using non-metric multidimensional scaling (NMDS), a number of species clusters were identified according to shared emission of unsaturated hydrocarbons, pyrazines, benzenoids, aldehydes, alkanes and terpenoids. In comparison, terpenoids are common in Zamia and dominant in Macrozamia species (both in the family Zamiaceae) while benzenoids, esters, and alcohols are dominant in Cycas (Cycadaceae) and in Stangeria (Stangeriaceae). It is likely that volatile variation among Encephalartos species reflects both phylogeny and adaptations to specific beetle pollinators.
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Affiliation(s)
- Terence N Suinyuy
- Kirstenbosch Research Centre, South African National Biodiversity Institute, P/Bag X7, Claremont 7735, Cape Town, South Africa.
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47
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Barrett SCH, Hough J. Sexual dimorphism in flowering plants. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:67-82. [PMID: 23183260 DOI: 10.1093/jxb/ers308] [Citation(s) in RCA: 170] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Among dioecious flowering plants, females and males often differ in a range of morphological, physiological, and life-history traits. This is referred to as sexual dimorphism, and understanding why it occurs is a central question in evolutionary biology. Our review documents a range of sexually dimorphic traits in angiosperm species, discusses their ecological consequences, and details the genetic and evolutionary processes that drive divergence between female and male phenotypes. We consider why sexual dimorphism in plants is generally less well developed than in many animal groups, and also the importance of sexual and natural selection in contributing to differences between the sexes. Many sexually dimorphic characters, including both vegetative and flowering traits, are associated with differences in the costs of reproduction, which are usually greater in females, particularly in longer-lived species. These differences can influence the frequency and distribution of females and males across resource gradients and within heterogeneous environments, causing niche differences and the spatial segregation of the sexes. The interplay between sex-specific adaptation and the breakdown of between-sex genetic correlations allows for the independent evolution of female and male traits, and this is influenced in some species by the presence of sex chromosomes. We conclude by providing suggestions for future work on sexual dimorphism in plants, including investigations of the ecological and genetic basis of intraspecific variation, and genetic mapping and expression studies aimed at understanding the genetic architecture of sexually dimorphic trait variation.
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Affiliation(s)
- Spencer C H Barrett
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario, Canada M5S 3B2.
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48
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Rosenstiel TN, Shortlidge EE, Melnychenko AN, Pankow JF, Eppley SM. Sex-specific volatile compounds influence microarthropod-mediated fertilization of moss. Nature 2012; 489:431-3. [PMID: 22810584 DOI: 10.1038/nature11330] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 06/15/2012] [Indexed: 11/09/2022]
Abstract
Sexual reproduction in non-vascular plants requires unicellular free-motile sperm to travel from male to female reproductive structures across the terrestrial landscape. Recent data suggest that microarthropods can disperse sperm in mosses. However, little is known about the chemical communication, if any, that is involved in this interaction or the relative importance of microarthropod dispersal compared to abiotic dispersal agents in mosses. Here we show that tissues of the cosmopolitan moss Ceratodon purpureus emit complex volatile scents, similar in chemical diversity to those described in pollination mutualisms between flowering plants and insects, that the chemical composition of C. purpureus volatiles are sex-specific, and that moss-dwelling microarthropods are differentially attracted to these sex-specific moss volatile cues. Furthermore, using experimental microcosms, we show that microarthropods significantly increase moss fertilization rates, even in the presence of water spray, highlighting the important role of microarthropod dispersal in contributing to moss mating success. Taken together, our results indicate the presence of a scent-based 'plant-pollinator-like' relationship that has evolved between two of Earth's most ancient terrestrial lineages, mosses and microarthropods.
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Affiliation(s)
- Todd N Rosenstiel
- Department of Biology and Center for Life in Extreme Environments, Portland State University, 1719 SW 10th Avenue, Portland, Oregon 97201, USA
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Soler CCL, Proffit M, Bessière JM, Hossaert-McKey M, Schatz B. Evidence for intersexual chemical mimicry in a dioecious plant. Ecol Lett 2012; 15:978-85. [PMID: 22762353 DOI: 10.1111/j.1461-0248.2012.01818.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Revised: 01/22/2012] [Accepted: 05/18/2012] [Indexed: 11/26/2022]
Abstract
The dioecious Mediterranean fig, Ficus carica, displays a unique phenology in which males sometimes bloom synchronously with females (in summer), and sometimes not (in spring). Ficus carica is engaged in an obligatory mutualism with a specific pollinating wasp, which reproduces only within figs, localising them by their specific scents. We show that scents emitted by male figs show seasonal variation within individual trees. Scents of summer male figs resemble those of the co-flowering females, and are different from those of the same male trees in spring, when female figs are absent. These differences hold even if only compounds electrophysiologically active for pollinators are considered. The similar scents of summer males and females may explain why the rewardless females are still pollinated. These results offer a tractable model for future studies of intersexual chemical mimicry in mutualistic pollination interactions.
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Affiliation(s)
- Catherine C L Soler
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE), UMR 5175 CNRS, 1919 route de Mende, 34293, Montpellier Cedex 5, France.
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50
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Brandenburg A, Kuhlemeier C, Bshary R. Innate Adjustment of Visitation Behavior to Rewarding and Reward-Minimized Petunia axillaris (Solanacea) Plants by Hawkmoth Manduca sexta (Sphingidae). Ethology 2012. [DOI: 10.1111/j.1439-0310.2012.02055.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Cris Kuhlemeier
- Institute of Plant Science; University of Bern; Bern; Switzerland
| | - Redouan Bshary
- Institute of Biology; University of Neuchâtel; Neuchâtel; Switzerland
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