1
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Boff S, Ayasse M. Exposure to sublethal concentration of flupyradifurone alters sexual behavior and cuticular hydrocarbon profile in Heriades truncorum, an oligolectic solitary bee. INSECT SCIENCE 2024; 31:859-869. [PMID: 37602924 DOI: 10.1111/1744-7917.13268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 07/11/2023] [Accepted: 07/25/2023] [Indexed: 08/22/2023]
Abstract
The aboveground oligolectic bee, Heriades truncorum, is a particularly good model for studying the impact of pesticides on sexual communication, since some aspects of its mating behavior have previously been described. We have tested (1) the interference of the pesticide flupyradifurone on male precopulatory behavior and male mating partner preferences, (2) the way that the pesticide interferes in male quality assessment by the female, and (3) the effects of the pesticide on the chemical compounds in the female cuticle. We exposed bees of both sexes to a sublethal concentration of flupyradifurone. Various behaviors were registered in a mating arena with two females (one unexposed and one exposed) and one male (either unexposed or exposed). Unexposed males were quicker to attempt to mate. Treatment also impacted precopulatory behavior and male quality assessment by females. Males approached unexposed females more quickly than insecticide-exposed ones. Females exposed to insecticide produced lower amounts of some cuticular hydrocarbons (sex pheromone candidates) and appeared less choosy than unexposed females. Our findings suggest that insecticide exposure affects sexual communication, playing a role both in male preference and in male quality assessment by the female.
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Affiliation(s)
- Samuel Boff
- Institute of Evolutionary Ecology and Conservation Genomics, Ulm University, Ulm, Germany
| | - Manfred Ayasse
- Institute of Evolutionary Ecology and Conservation Genomics, Ulm University, Ulm, Germany
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2
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Francisco A, Ascensão L. Osmophore Structure and Labellum Micromorphology in Ophrys speculum (Orchidaceae): New Interpretations of Floral Features and Implications for a Specific Sexually Deceptive Pollination Interaction. PLANTS (BASEL, SWITZERLAND) 2024; 13:1413. [PMID: 38794483 PMCID: PMC11125028 DOI: 10.3390/plants13101413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 05/12/2024] [Accepted: 05/14/2024] [Indexed: 05/26/2024]
Abstract
Pollination by sexual deception specifically attracts male insects, through the floral scent and particular morphological features of the flower that serve as visual and tactile stimuli. The unique bond between the Ophrys speculum orchid and the male Dasyscolia ciliata wasp primarily stems from a few distinctive semiochemicals that mimic the female wasp's sex pheromone, although the floral scent comprises a variety of compounds. An osmophore producing highly volatile compounds has been documented in four close relatives of O. speculum and is now being also investigated in this species. Given the existing debates regarding the structure of the labellum and stigmatic cavity in O. speculum, this study details their micromorphology. Additionally, comparisons of O. speculum flowers and female D. ciliata wasps under stereomicroscopy and scanning electron microscopy are conducted to seek new evidence of visual and tactile mimicry. The findings confirm that (i) an osmophore is present at the apical margin of the labellum in O. speculum flowers; (ii) the labellum features a distinct basal field homologous to those found in other Ophrys species; and (iii) the basal labellum region closely mimics the female wasp's thorax and wings. The implications of these novel floral features are discussed within an evolutionary context.
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Affiliation(s)
- Ana Francisco
- Centro de Estudos do Ambiente e do Mar (CESAM Lisboa), Faculdade de Ciências da Universidade de Lisboa (FCUL), C2, Campo Grande, 1749-016 Lisboa, Portugal
| | - Lia Ascensão
- Centro de Estudos do Ambiente e do Mar (CESAM Lisboa), Faculdade de Ciências da Universidade de Lisboa (FCUL), C2, Campo Grande, 1749-016 Lisboa, Portugal
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3
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Cui J, Zhou J, Du W, Guo D, Tang X, Zhao W, Lu M, Yu K, Luo Z, Chen Y, Wang Q, Gao T, Schwab WG, Song C. Distribution of and Temporal Variation in Volatiles in Tea ( Camellia sinensis) Flowers during the Opening Stages. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:19682-19693. [PMID: 37988651 DOI: 10.1021/acs.jafc.3c02690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2023]
Abstract
Tea (Camellia sinensis) flowers emit a large amount of volatiles that attract pollinators. However, few studies have characterized temporal and spatial variation in tea floral volatiles. To investigate the distribution of volatiles within tea flowers and their variation among opening stages, volatile components from different parts of tea flowers and different opening stages were collected by headspace solid-phase microextraction and analyzed by gas chromatography-mass spectrometry. A total of 51 volatile compounds of eight chemical classes were identified in the tea flowers. Volatile compounds were most abundant in tea flowers of the Shuchazao cultivar. Acetophenone, 1-phenylethanol, 2-phenylethanol, and benzyl alcohol were the most abundant volatiles. Terpenes were common in the sepals, and benzoids were common in the stamens. The fatty acid derivatives were mainly distributed in the pistils and receptacles and were less abundant in the petals, sepals, and stamens. During the opening phase of tea flowers, the volatile content increased 12-fold, which mainly stemmed from the increase in benzoids. These results enhance our understanding of the formation of volatiles in tea flowers.
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Affiliation(s)
- Jilai Cui
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang Ave W., Hefei, Anhui 230036, People's Republic of China
- College of Life Science, Xinyang Normal University, 237 Nanhu R., Xinyang, Henan 464000, People's Republic of China
| | - Jie Zhou
- College of Life Science, Xinyang Normal University, 237 Nanhu R., Xinyang, Henan 464000, People's Republic of China
| | - Wenkai Du
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang Ave W., Hefei, Anhui 230036, People's Republic of China
| | - Danyang Guo
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang Ave W., Hefei, Anhui 230036, People's Republic of China
| | - Xiaoyan Tang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang Ave W., Hefei, Anhui 230036, People's Republic of China
| | - Wei Zhao
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang Ave W., Hefei, Anhui 230036, People's Republic of China
| | - Mengqian Lu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang Ave W., Hefei, Anhui 230036, People's Republic of China
| | - Keke Yu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang Ave W., Hefei, Anhui 230036, People's Republic of China
| | - Zhengwei Luo
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang Ave W., Hefei, Anhui 230036, People's Republic of China
| | - Yushan Chen
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang Ave W., Hefei, Anhui 230036, People's Republic of China
| | - Qiang Wang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang Ave W., Hefei, Anhui 230036, People's Republic of China
| | - Ting Gao
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang Ave W., Hefei, Anhui 230036, People's Republic of China
| | - Wilfried G Schwab
- Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany
| | - Chuankui Song
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang Ave W., Hefei, Anhui 230036, People's Republic of China
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4
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Perkins J, Hayashi T, Peakall R, Flematti GR, Bohman B. The volatile chemistry of orchid pollination. Nat Prod Rep 2023; 40:819-839. [PMID: 36691832 DOI: 10.1039/d2np00060a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Covering: up to September 2022Orchids are renowned not only for their diversity of floral forms, but also for their many and often highly specialised pollination strategies. Volatile semiochemicals play a crucial role in the attraction of a wide variety of insect pollinators of orchids. The compounds produced by orchid flowers are as diverse as the pollinators they attract, and here we summarise some of the chemical diversity found across orchid taxa and pollination strategies. We focus on compounds that have been experimentally demonstrated to underpin pollinator attraction. We also highlight the structural elucidation and synthesis of a select subset of important orchid pollinator attractants, and discuss the ecological significance of the discoveries, the gaps in our current knowledge of orchid pollination chemistry, and some opportunities for future research in this field.
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Affiliation(s)
- James Perkins
- Research School of Biology, The Australian National University, Australia
| | - Tobias Hayashi
- Research School of Biology, The Australian National University, Australia
| | - Rod Peakall
- Research School of Biology, The Australian National University, Australia.,School of Molecular Sciences, The University of Western Australia, Australia
| | - Gavin R Flematti
- School of Molecular Sciences, The University of Western Australia, Australia
| | - Björn Bohman
- Research School of Biology, The Australian National University, Australia.,School of Molecular Sciences, The University of Western Australia, Australia.,Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Sweden.
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5
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Cozzolino S, Scopece G, Lussu M, Cortis P, Schiestl FP. Do floral and ecogeographic isolation allow the co-occurrence of two ecotypes of Anacamptis papilionacea (Orchidaceae)? Ecol Evol 2021; 11:9917-9931. [PMID: 34367549 PMCID: PMC8328454 DOI: 10.1002/ece3.7432] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 02/10/2021] [Accepted: 02/18/2021] [Indexed: 11/08/2022] Open
Abstract
Ecotypes are relatively frequent in flowering plants and considered central in ecological speciation as local adaptation can promote the insurgence of reproductive isolation. Without geographic isolation, gene flow usually homogenizes the allopatrically generated phenotypic and ecological divergences, unless other forms of reproductive isolation keep them separated. Here, we investigated two orchid ecotypes with marked phenotypic floral divergence that coexist in contact zones. We found that the two ecotypes show different ecological habitat preferences with one being more climatically restricted than the other. The ecotypes remain clearly morphologically differentiated both in allopatry and in sympatry and differed in diverse floral traits. Despite only slightly different flowering times, the two ecotypes achieved floral isolation thanks to different pollination strategies. We found that both ecotypes attract a wide range of insects, but the ratio of male/female attracted by the two ecotypes was significantly different, with one ecotype mainly attracts male pollinators, while the other mainly attracts female pollinators. As a potential consequence, the two ecotypes show different pollen transfer efficiency. Experimental plots with pollen staining showed a higher proportion of intra- than interecotype movements confirming floral isolation between ecotypes in sympatry while crossing experiments excluded evident postmating barriers. Even if not completely halting the interecotypes pollen flow in sympatry, such incipient switch in pollination strategy between ecotypes may represent a first step on the path toward evolution of sexual mimicry in Orchidinae.
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Affiliation(s)
| | - Giovanni Scopece
- Department of BiologyUniversity Federico II of NaplesNapoliItaly
| | - Michele Lussu
- Department of Life and Environmental SciencesUniversity of CagliariCagliariItaly
- Istituto Regionale per la Floricoltura (IRF)SanremoItaly
| | - Pierluigi Cortis
- Department of Life and Environmental SciencesUniversity of CagliariCagliariItaly
| | - Florian P. Schiestl
- Department of Systematic and Evolutionary Botany and Botanical GardensUniversity of ZurichZurichSwitzerland
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6
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Baguette M, Bertrand JAM, Stevens VM, Schatz B. Why are there so many bee-orchid species? Adaptive radiation by intra-specific competition for mnesic pollinators. Biol Rev Camb Philos Soc 2020; 95:1630-1663. [PMID: 32954662 DOI: 10.1111/brv.12633] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 06/09/2020] [Accepted: 06/15/2020] [Indexed: 01/08/2023]
Abstract
Adaptive radiations occur mostly in response to environmental variation through the evolution of key innovations that allow emerging species to occupy new ecological niches. Such biological innovations may play a major role in niche divergence when emerging species are engaged in reciprocal ecological interactions. To demonstrate coevolution is a difficult task; only a few studies have confirmed coevolution as driver of speciation and diversification. Herein we review current knowledge about bee orchid (Ophrys spp.) reproductive biology. We propose that the adaptive radiation of the Mediterranean orchid genus Ophrys, comprising several hundred species, is due to coevolutionary dynamics between these plants and their pollinators. We suggest that pollination by sexual swindling used by Ophrys orchids is the main driver of this coevolution. Flowers of each Ophrys species mimic a sexually receptive female of one particular insect species, mainly bees. Male bees are first attracted by pseudo-pheromones emitted by Ophrys flowers that are similar to the sexual pheromones of their females. Males then are lured by the flower shape, colour and hairiness, and attempt to copulate with the flower, which glues pollen onto their bodies. Pollen is later transferred to the stigma of another flower of the same Ophrys species during similar copulation attempts. In contrast to rewarding pollination strategies, Ophrys pollinators appear to be parasitized. Here we propose that this apparent parasitism is in fact a coevolutionary relationship between Ophrys and their pollinators. For plants, pollination by sexual swindling could ensure pollination efficiency and specificity, and gene flow among populations. For pollinators, pollination by sexual swindling could allow habitat matching and inbreeding avoidance. Pollinators might use the pseudo-pheromones emitted by Ophrys to locate suitable habitats from a distance within complex landscapes. In small populations, male pollinators would disperse once they have memorized the local diversity of sexual pseudo-pheromone bouquets or if all Ophrys flowers are fertilized and thus repel pollinators via production of repulsive pheromones that mimic those produced by fertilized female bees. We propose the following evolutionary scenario: Ophrys radiation is driven by strong intra-specific competition among Ophrys individuals for the attraction of species-specific pollinators, which is a consequence of the high cognitive abilities of pollinators. Male bees record the pheromone signatures of kin or of previously courted partners to avoid further copulation attempts, thereby inducing strong selection on Ophrys for variation in odour bouquets emitted by individual flowers. The resulting odour bouquets could by chance correspond to pseudo-pheromones of the females of another bee species, and thus attract a new pollinator. If such pollinator shifts occur simultaneously in several indivuals, pollen exchanges might occur and initiate speciation. To reinforce the attraction of the new pollinator and secure prezygotic isolation, the following step is directional selection on flower phenotypes (shape, colour and hairiness) towards a better match with the body of the pollinator's female. Pollinator shift and the resulting prezygotic isolation is adaptive for new Ophrys species because they may benefit from competitor-free space for limited pollinators. We end our review by proritizing several critical research avenues.
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Affiliation(s)
- Michel Baguette
- Institut Systématique, Evolution, Biodiversité (ISYEB), UMR 7205 Museum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, F-75005, Paris, France.,Centre National de la Recherche Scientifique and Université Paul Sabatier Toulouse III, SETE Station d'Ecologie Théorique et Expérimentale, UMR 5321, F-09200, Moulis, France
| | - Joris A M Bertrand
- LGDP (Laboratoire Génome et Développement des Plantes) UMR5096, Université de Perpignan Via Domitia -CNRS, F-66860, Perpignan, France
| | - Virginie M Stevens
- Centre National de la Recherche Scientifique and Université Paul Sabatier Toulouse III, SETE Station d'Ecologie Théorique et Expérimentale, UMR 5321, F-09200, Moulis, France
| | - Bertrand Schatz
- CEFE (Centre d'Ecologie Fonctionnelle et Evolutive) UMR 5175, CNRS - Université de Montpellier - Université Paul Valéry - EPHE, 1919 Route de Mende, 34293, Montpellier, France
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7
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Martel C, Neubig KM, Williams NH, Ayasse M. The uncinate viscidium and floral setae, an evolutionary innovation and exaptation to increase pollination success in the Telipogon alliance (Orchidaceae: Oncidiinae). ORG DIVERS EVOL 2020. [DOI: 10.1007/s13127-020-00457-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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8
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Proffit M, Lapeyre B, Buatois B, Deng X, Arnal P, Gouzerh F, Carrasco D, Hossaert-McKey M. Chemical signal is in the blend: bases of plant-pollinator encounter in a highly specialized interaction. Sci Rep 2020; 10:10071. [PMID: 32572098 PMCID: PMC7308319 DOI: 10.1038/s41598-020-66655-w] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 05/14/2020] [Indexed: 11/25/2022] Open
Abstract
In several highly specialized plant-insect interactions, scent-mediated specificity of pollinator attraction is directed by the emission and detection of volatile organic compounds (VOCs). Although some plants engaged in such interactions emit singular compounds, others emit mixtures of VOCs commonly emitted by plants. We investigated the chemical ecological bases of host plant recognition in the nursery pollination mutualism between the dioecious Ficus carica and its specific pollinator Blastophaga psenes. Using Y-tube olfactometer tests, we show that B. psenes females are attracted by VOCs of receptive figs of both sexes and do not exhibit preference for VOCs of either male or female figs. Electrophysiological tests and chemical analysis revealed that of all the VOCs emitted by receptive figs, only five were found to be active on female antennae. Behavioural tests show that, in contrast to VOCs presented alone, only a blend with a particular proportion of four of these VOCs is as attractive as the odour of receptive figs, and that if there is a very small change in this blend proportion, the pollinator is no longer attracted. This study revealed that in highly specialized mutualistic interactions specificity could be mediated by a particular blend of common compounds emitted by plants.
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Affiliation(s)
- Magali Proffit
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Univ Paul Valéry Montpellier 3, Montpellier, France.
| | - Benoit Lapeyre
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Univ Paul Valéry Montpellier 3, Montpellier, France
| | - Bruno Buatois
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Univ Paul Valéry Montpellier 3, Montpellier, France
| | - Xiaoxia Deng
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Univ Paul Valéry Montpellier 3, Montpellier, France
| | - Pierre Arnal
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Univ Paul Valéry Montpellier 3, Montpellier, France
| | - Flora Gouzerh
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Univ Paul Valéry Montpellier 3, Montpellier, France.,MIVEGEC, Univ Montpellier, IRD, CNRS, Montpellier, France
| | - David Carrasco
- MIVEGEC, Univ Montpellier, IRD, CNRS, Montpellier, France
| | - Martine Hossaert-McKey
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Univ Paul Valéry Montpellier 3, Montpellier, France
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9
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Distinct Roles of Cuticular Aldehydes as Pheromonal Cues in Two Cotesia Parasitoids. J Chem Ecol 2020; 46:128-137. [PMID: 31907752 DOI: 10.1007/s10886-019-01142-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 12/04/2019] [Accepted: 12/20/2019] [Indexed: 10/25/2022]
Abstract
Cuticular compounds (CCs) that cover the surface of insects primarily serve as protection against entomopathogens, harmful substances, and desiccation. However, CCs may also have secondary signaling functions. By studying the role of CCs in intraspecific interactions, we may advance our understanding of the evolution of pheromonal communication in insects. We previously found that the gregarious parasitoid, Cotesia glomerata (L.), uses heptanal as a repellent pheromone to help avoid mate competition among sibling males, whereas another cuticular aldehyde, nonanal, is part of the female-produced attractive sex pheromone. Here, we show that the same aldehydes have different pheromonal functions in a related solitary parasitoid, Cotesia marginiventris (Cresson). Heptanal enhances the attractiveness of the female's sex pheromone, whereas nonanal does not affect a female's attractiveness. Hence, these common aldehydes are differentially used by the two Cotesia species to mediate, synergistically, the attractiveness of the main constituents of their respective sex pheromones. The specificity of the complete sex pheromone blend is apparently regulated by two specific, less volatile compounds, which evoke strong electroantennographic (EAG) responses. This is the first demonstration that volatile CCs have evolved distinct pheromonal functions to aid divergent mating strategies in closely related species. We discuss the possibility that additional compounds are involved in attraction and that, like the aldehydes, they are likely oxidative products of unsaturated cuticular hydrocarbons.
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10
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Martel C, Francke W, Ayasse M. The chemical and visual bases of the pollination of the Neotropical sexually deceptive orchid Telipogon peruvianus. THE NEW PHYTOLOGIST 2019; 223:1989-2001. [PMID: 31074029 DOI: 10.1111/nph.15902] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 05/01/2019] [Indexed: 06/09/2023]
Abstract
Deception of floral visitors in pollination systems is widely distributed among flowering plants. In deceptive systems, the flower (or part of it) or inflorescence mimics either a specific or an unspecific model to attract pollinators. A previous study showed that Telipogon peruvianus flowers developed sexual deception for pollination. However, it was unknown which stimuli were playing a role in pollination. Therefore, we aim to throw some light onto these questions using colour and chemical analysis and biotests. Interestingly, using spectral reflectance, we show here that the flowers present high contrast similar to that produced by a female tachinid fly sitting on a daisy inflorescence, which is used as food resource. We also tested the role of chemical signals in pollinator attraction by collecting floral and female extracts for chemical and electrophysiological analyses, and carried out behavioural tests. For biotests, various treatments, including synthetic mixtures of the electrophysiologically active compounds found in common in females and flowers, have demonstrated that T. peruvianus flowers mimic the sexual pheromone of their pollinator's females. Thus, we give evidence that T. peruvianus flowers mimic a model composed of two organisms. Our study contributes to the understanding of the evolution of deceptive pollination.
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Affiliation(s)
- Carlos Martel
- Institute of Evolutionary Ecology and Conservation Genomics, Universität Ulm, Albert-Einstein-Allee 11, D-89081, Ulm, Germany
| | - Wittko Francke
- Institut für Organische Chemie, Universität Hamburg, Martin-Luther-King-Platz 6, D-20146, Hamburg, Germany
| | - Manfred Ayasse
- Institute of Evolutionary Ecology and Conservation Genomics, Universität Ulm, Albert-Einstein-Allee 11, D-89081, Ulm, Germany
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11
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Zito P, Rosselli S, Bruno M, Maggio A, Sajeva M. Floral scent in a sexually deceptive Ophrys orchid: from headspace collections to solvent extractions. PLANT SIGNALING & BEHAVIOR 2018; 14:1552056. [PMID: 30507332 PMCID: PMC6351094 DOI: 10.1080/15592324.2018.1552056] [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: 09/17/2018] [Revised: 11/13/2018] [Accepted: 11/18/2018] [Indexed: 06/09/2023]
Abstract
Sexually deceptive orchid flowers use visual, tactile and olfactory cues of female insects in order to attract males of one or a few closely related species as pollinators. Ophrys L. is the most species-rich genus of sexually deceptive orchids in the Mediterranean Basin. Despite Ophrys pollinated by Andrena male bees use alkanes and mainly alkenes with specific double-bond positions as key signals that trigger pseudocopulatory behavior, some volatile organic compounds (VOCs) with low molecular weight were found as long-range attractants non-eliciting copulatory behavior. Since floral scents in Ophrys have been extensively studied by solvent extractions here we aimed to understand which floral volatiles are found when two different collection methods are used in Ophrys panormitana flowers. By knowing their chemical composition, we could better understand the scent chemistry of this Ophrys species without overlooking VOCs which could also have a function in its pollination biology. Scent samples collected by dynamic headspace and by solvent extraction were analyzed by gas chromatography/mass spectrometry (GC/MS). The floral scent of O. panormitana is composed by a bouquet of VOCs with lower and higher molecular weights. The headspace samples contained VOCs with higher volatility (mainly one aliphatic alcohol and two aliphatic ketones) whereas the solvent extracts were composed by VOCs with lower volatility (exclusively long-chain alkanes and alkenes). Overlapping in VOCs between headspace and solvent samples were not found. For the first time Andrena nigroaenea was observed during the pseudocopulation and removing the pollinaria of a flower of O. panormitana. Abbreviations: VOCs, volatile organic compounds; GC/MS, gas chromatography-mass spectrometry; KRI, Kovats Retention Indices.
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Affiliation(s)
- Pietro Zito
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Palermo, Italy
| | - Sergio Rosselli
- Department of Agricultural, Food and Forest Sciences, University of Palermo, Palermo, Italy
| | - Maurizio Bruno
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Palermo, Italy
| | - Antonella Maggio
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Palermo, Italy
| | - Maurizio Sajeva
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Palermo, Italy
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12
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Comparative transcriptomics provides insight into the molecular basis of species diversification of section Trigonopedia (Cypripedium) on the Qinghai-Tibetan Plateau. Sci Rep 2018; 8:11640. [PMID: 30076357 PMCID: PMC6076244 DOI: 10.1038/s41598-018-30147-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 07/24/2018] [Indexed: 11/15/2022] Open
Abstract
Deceptive pollination is key to the species richness of Orchidaceae. However, the genetic basis of species diversification is still under study. Section Trigonopedia is a monophyletic clade of genus Cypripedium distributed in the southwest of China. The species of this section are pollinated by different flies. Pollinator differentiation makes section Trigonopedia an ideal group for studying the genetic basis underlying species diversification. Here, we sequenced the transcriptomes of eight species of the genus Cypripedium, including six co-flowering species of section Trigonopedia and two species outside this section as an outgroup. We reconstructed the phylogeny of the section with the combined 1572 single-copy genes extracted from the eight species and produced a highly resolved tree of the section. Furthermore, we combined substitution rate estimation and differential expression analysis to identify candidate genes, including genes related to floral scent synthesis and environmental adaptation, involved in species differentiation. Field investigations showed that these species have adapted to different habitats. We propose that the species diversification in this section is initiated by floral scent differentiation, followed by habitat differentiation, finally leading to speciation. This study sheds novel light on the diversification of closely related orchid species in the Qinghai-Tibetan region.
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Bohman B, Karton A, Flematti GR, Scaffidi A, Peakall R. Structure-Activity Studies of Semiochemicals from the Spider Orchid Caladenia plicata for Sexual Deception. J Chem Ecol 2018; 44:436-443. [DOI: 10.1007/s10886-018-0946-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 01/17/2018] [Accepted: 03/12/2018] [Indexed: 01/07/2023]
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Rakosy D, Cuervo M, Paulus HF, Ayasse M. Looks matter: changes in flower form affect pollination effectiveness in a sexually deceptive orchid. J Evol Biol 2017; 30:1978-1993. [PMID: 28787530 DOI: 10.1111/jeb.13153] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 07/23/2017] [Accepted: 07/29/2017] [Indexed: 01/30/2023]
Abstract
Many species of the sexually deceptive genus Ophrys are characterized by insect-like flowers. Their form has been traditionally considered to play an important role in pollinator attraction and manipulation. Yet, the evolution of the floral form remains insufficiently understood. We hypothesize that pollinator-mediated selection is essential for driving floral form evolution in Ophrys, but that form components are being subjected to varying selection pressures depending on their role in mediating interactions with pollinators. By using the Eucera-pollinated Ophrys leochroma as a model, our aim has been to assess whether and in what manner pollination effectiveness is altered by experimental manipulation of the flower form. Our results show that floral form plays an essential and, so far, underestimated role in ensuring effective pollination by mechanically guiding pollinators towards the reproductive structures of the flower. Pollinators are significantly less effective in interacting with flowers having forms altered to resemble those of species pollinated by different hymenopteran genera. Further, those components used by pollinators as gripping points were found to be more effective in ensuring pollinia transfer than those with which pollinators do not directly interact. Thus, mechanically active and inactive components appear to be under different selection pressures. As a consequence, mechanically active components of the flower form could reflect adaptations to the interaction with particular pollinator groups, whereas mechanically inactive components can vary more freely. Disentangling selection patterns between the functionally different components of flower form may provide valuable insights into the mechanisms driving the morphological diversification of sexually deceptive pollination systems.
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Affiliation(s)
- D Rakosy
- Integrative Zoology, Faculty of Life Sciences, University Vienna, Vienna, Austria.,Systematic and Evolutionary Botany, Faculty of Life Sciences, University Vienna, Vienna, Austria
| | - M Cuervo
- Institute of Evolutionary Ecology and Conservation Genomics, University Ulm, Ulm, Germany
| | - H F Paulus
- Integrative Zoology, Faculty of Life Sciences, University Vienna, Vienna, Austria
| | - M Ayasse
- Institute of Evolutionary Ecology and Conservation Genomics, University Ulm, Ulm, Germany
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