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Sletvold N, Joffard N, Söderquist L. Fine-scale genetic structure in the orchid Gymnadenia conopsea is not associated with local density of flowering plants. Am J Bot 2024; 111:e16273. [PMID: 38290971 DOI: 10.1002/ajb2.16273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 11/16/2023] [Accepted: 11/16/2023] [Indexed: 02/01/2024]
Abstract
PREMISE Density-dependent pollinator visitation can lead to density-dependent mating patterns and within-population genetic structure. In Gymnadenia conopsea, individuals in low-density patches receive more self pollen than individuals in high-density patches, suggesting higher relatedness at low density. Ongoing fragmentation is also expected to cause more local matings, potentially leading to biparental inbreeding depression. METHODS To evaluate whether relatedness decreases with local density, we analyzed 1315 SNP loci in 113 individuals within two large populations. We quantified within-population genetic structure in one of the populations, recorded potential habitat barriers, and visualized gene flow using estimated effective migration surfaces (EEMS). We further estimated the magnitude of biparental inbreeding depression that would result from matings restricted to within 5 m. RESULTS There was no significant relationship between local density and relatedness in any population. We detected significant fine-scale genetic structure consistent with isolation by distance, with positive kinship coefficients at distances below 10 m. Kinship coefficients were low, and predicted biparental inbreeding depression resulting from matings within the closest 5 m was a modest 1-3%. The EEMS suggested that rocks and bushes may act as barriers to gene flow within a population. CONCLUSIONS The results suggest that increased self-pollen deposition in sparse patches does not necessarily cause higher selfing rates or that inbreeding depression results in low establishment success of inbred individuals. The modest relatedness suggests that biparental inbreeding depression is unlikely to be an immediate problem following fragmentation of large populations. The results further indicate that habitat structure may contribute to governing fine-scale genetic structure in G. conopsea.
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Affiliation(s)
- Nina Sletvold
- Plant Ecology and Evolution, Department of Ecology and Genetics, EBC, Uppsala University, SE-752 36 Uppsala, Sweden
| | - Nina Joffard
- Plant Ecology and Evolution, Department of Ecology and Genetics, EBC, Uppsala University, SE-752 36 Uppsala, Sweden
- UMR 8198 -Evo-Eco-Paleo, University of Lille, Lille, France
| | - Linus Söderquist
- Plant Ecology and Evolution, Department of Ecology and Genetics, EBC, Uppsala University, SE-752 36 Uppsala, Sweden
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Joffard N, Buatois B, Arnal V, Véla E, Montgelard C, Schatz B. Delimiting species in the taxonomically challenging orchid section Pseudophrys: Bayesian analyses of genetic and phenotypic data. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.1058550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Accurate species delimitation is critical for biodiversity conservation. Integrative taxonomy has been advocated for a long time, yet tools allowing true integration of genetic and phenotypic data have been developed quite recently and applied to few models, especially in plants. In this study, we investigated species boundaries within a group of twelve Pseudophrys taxa from France by analyzing genetic, morphometric and chemical (i.e., floral scents) data in a Bayesian framework using the program integrated Bayesian Phylogenetics and Phylogeography (iBPP). We found that these twelve taxa were merged into four species when only genetic data were used, while most formally described species were recognized as such when only phenotypic (either morphometric or chemical) data were used. The result of the iBPP analysis performed on both genetic and phenotypic data supports the proposal to merge Ophrys bilunulata and O. marmorata on the one hand, and O. funerea and O. zonata on the other hand. Our results show that phenotypic data are particularly informative in the section Pseudophrys and that their integration in a model-based method significantly improves the accuracy of species delimitation. We are convinced that the integrative taxonomic approach proposed in this study holds great promise to conduct taxonomic revisions in other orchid groups.
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Opedal ØH, Gross K, Chapurlat E, Parachnowitsch A, Joffard N, Sletvold N, Ovaskainen O, Friberg M. Measuring, comparing and interpreting phenotypic selection on floral scent. J Evol Biol 2022; 35:1432-1441. [PMID: 36177776 PMCID: PMC9828191 DOI: 10.1111/jeb.14103] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 09/04/2022] [Accepted: 09/07/2022] [Indexed: 01/12/2023]
Abstract
Natural selection on floral scent composition is a key element of the hypothesis that pollinators and other floral visitors drive scent evolution. The measure of such selection is complicated by the high-dimensional nature of floral scent data and uncertainty about the cognitive processes involved in scent-mediated communication. We use dimension reduction through reduced-rank regression to jointly estimate a scent composite trait under selection and the strength of selection acting on this trait. To assess and compare variation in selection on scent across species, time and space, we reanalyse 22 datasets on six species from four previous studies. The results agreed qualitatively with previous analyses in terms of identifying populations and scent compounds subject to stronger selection but also allowed us to evaluate and compare the strength of selection on scent across studies. Doing so revealed that selection on floral scent was highly variable, and overall about as common and as strong as selection on other phenotypic traits involved in pollinator attraction or pollen transfer. These results are consistent with an important role of floral scent in pollinator attraction. Our approach should be useful for further studies of plant-animal communication and for studies of selection on other high-dimensional phenotypes. In particular, our approach will be useful for studies of pollinator-mediated selection on complex scent blends comprising many volatiles, and when no prior information on the physiological responses of pollinators to scent compounds is available.
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Affiliation(s)
| | - Karin Gross
- Department of Environment & BiodiversityParis Lodron University of SalzburgSalzburgAustria
| | - Elodie Chapurlat
- Plant Ecology and Evolution, Department of Ecology and Genetics, EBCUppsala UniversityUppsalaSweden,Department of EcologySwedish University of Agricultural SciencesUppsalaSweden
| | - Amy Parachnowitsch
- Department of BiologyUniversity of New BrunswickFrederictonNew BrunswickCanada
| | - Nina Joffard
- University of Lille, UMR 8198 – Evo‐Eco‐PaleoLilleFrance
| | - Nina Sletvold
- Plant Ecology and Evolution, Department of Ecology and Genetics, EBCUppsala UniversityUppsalaSweden
| | - Otso Ovaskainen
- Department of Biological and Environmental ScienceUniversity of JyväskyläJyväskyläFinland,Organismal and Evolutionary Biology Research ProgrammeUniversity of HelsinkiHelsinkiFinland,Centre for Biodiversity Dynamics, Department of BiologyNorwegian University of Science and TechnologyTrondheimNorway
| | - Magne Friberg
- Biodiversity Unit, Department of BiologyLund UniversityLundSweden
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Joffard N, Olofsson C, Friberg M, Sletvold N. Extensive pollinator sharing does not promote character displacement in two orchid congeners. Evolution 2022; 76:749-764. [PMID: 35188979 DOI: 10.1111/evo.14446] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 01/07/2022] [Accepted: 01/18/2022] [Indexed: 01/22/2023]
Abstract
Pollinator sharing between close relatives can be costly and can promote pollination niche partitioning and floral divergence. This should be reflected by a higher species divergence in sympatry than in allopatry. We tested this hypothesis in two orchid congeners with overlapping distributions and flowering times. We characterized floral traits and pollination niches and quantified pollen limitation in 15 pure and mixed populations, and we measured phenotypic selection on floral traits and performed controlled crosses in one mixed site. Most floral traits differed between species, yet pollinator sharing was extensive. Only the timing of scent emission diverged more in mixed sites than in pure sites, and this was not mirrored by the timing of pollinator visitation. We did not detect divergent selection on floral traits. Seed production was pollen limited in most populations but not more severely in mixed sites than in pure sites. Interspecific crosses produced the same or a higher proportion of viable seeds than intraspecific crosses. The two orchid species attract the same pollinator species despite showing divergent floral traits. However, this does not promote character displacement, implying a low cost of pollinator sharing. Our results highlight the importance of characterizing both traits and ecological niches in character displacement studies.
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Affiliation(s)
- Nina Joffard
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, Uppsala, 752 36, Sweden.,University of Lille, UMR 8198 - Evo-Eco-Paleo, Villeneuve d'Ascq, F-59655, France
| | - Caroliné Olofsson
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, Uppsala, 752 36, Sweden
| | - Magne Friberg
- Department of Biology, Lund University, Lund, SE-223 62, Sweden
| | - Nina Sletvold
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, Uppsala, 752 36, Sweden
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Joffard N, Silva WTAF, Twyford AD. Digest: The role of postzygotic isolation in Mimulus speciation. Evolution 2021; 75:756-758. [PMID: 33469918 DOI: 10.1111/evo.14175] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 12/30/2020] [Indexed: 01/08/2023]
Abstract
Recently diverged species often show incomplete reproductive isolation and subsequently experience hybridization and introgression. The plant genus Mimulus includes many such examples of closely related taxa that prove useful for studying incipient speciation. However, Sandstedt et al. show that in contrast to other Mimulus species, species of the M. tilingii complex are characterized by strong postzygotic isolation mediated by multiple barriers. This finding highlights the diverse speciation histories of related plant groups.
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Affiliation(s)
- Nina Joffard
- Evolutionary Biology Centre, Department of Ecology and Genetics, Plant Ecology and Evolution Program, Uppsala University, Uppsala, Sweden
| | - Willian T A F Silva
- Centre for Environmental and Climate Research, Lund University, Lund, Sweden
| | - Alex D Twyford
- Ashworth Laboratories, Institute of Evolutionary Biology, The University of Edinburgh, Edinburgh, UK.,Royal Botanic Garden Edinburgh, Edinburgh, UK
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Joffard N, Arnal V, Buatois B, Schatz B, Montgelard C. Floral scent evolution in the section Pseudophrys: pollinator-mediated selection or phylogenetic constraints? Plant Biol (Stuttg) 2020; 22:881-889. [PMID: 32130747 DOI: 10.1111/plb.13104] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 02/07/2020] [Indexed: 06/10/2023]
Abstract
Sexually deceptive orchid species from the Mediterranean genus Ophrys usually interact with one or a few pollinator species by means of specific floral scents. In this study, we investigated the respective role of pollinator-mediated selection and phylogenetic constraints in the evolution of floral scents in the section Pseudophrys. We built a phylogenetic tree of 19 Pseudophrys species based on three nuclear loci; we gathered a dataset on their pollination interactions from the literature and from our own field data; and we extracted and analysed their floral scents using solid phase microextraction and gas chromatography-mass spectrometry. We then quantified the phylogenetic signal carried by floral scents and investigated the link between plant-pollinator interactions and floral scent composition using phylogenetic comparative methods. We confirmed the monophyly of the section Pseudophrys and demonstrated the existence of three main clades within this section. We found that floral scent composition is affected by both phylogenetic relationships among Ophrys species and pollination interactions, with some compounds (especially fatty acid esters) carrying a significant phylogenetic signal and some (especially alkenes and alkadienes) generating dissimilarities between closely related Pseudophrys pollinated by different insects. Our results show that in the section Pseudophrys, floral scents are shaped both by pollinator-mediated selection and by phylogenetic constraints, but that the relative importance of these two evolutionary forces differ among compound classes, probably reflecting distinct selective pressures imposed upon behaviourally active and non-active compounds.
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Affiliation(s)
- N Joffard
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE), UMR 5175, CNRS - Université de Montpellier - Université Paul Valéry Montpellier - EPHE, Montpellier, France
| | - V Arnal
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE), UMR 5175, CNRS - Université de Montpellier - Université Paul Valéry Montpellier - EPHE, Montpellier, France
| | - B Buatois
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE), UMR 5175, CNRS - Université de Montpellier - Université Paul Valéry Montpellier - EPHE, Montpellier, France
| | - B Schatz
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE), UMR 5175, CNRS - Université de Montpellier - Université Paul Valéry Montpellier - EPHE, Montpellier, France
| | - C Montgelard
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE), UMR 5175, CNRS - Université de Montpellier - Université Paul Valéry Montpellier - EPHE, Montpellier, France
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Joffard N, Le Roncé I, Langlois A, Renoult J, Buatois B, Dormont L, Schatz B. Floral trait differentiation in Anacamptis coriophora: Phenotypic selection on scents, but not on colour. J Evol Biol 2020; 33:1028-1038. [PMID: 32500947 DOI: 10.1111/jeb.13657] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 05/14/2020] [Accepted: 05/23/2020] [Indexed: 01/26/2023]
Abstract
Current divergent selection may promote floral trait differentiation among conspecific populations in flowering plants. However, whether this applies to complex traits such as colour or scents has been little studied, even though these traits often vary within species. In this study, we compared floral colour and odour as well as selective pressures imposed upon these traits among seven populations belonging to three subspecies of the widespread, generalist orchid Anacamptis coriophora. Colour was characterized using calibrated photographs, and scents were sampled using dynamic headspace extraction and analysed using gas chromatography-mass spectrometry. We then quantified phenotypic selection exerted on these traits by regressing fruit set values on floral trait values. We showed that the three studied subspecies were characterized by different floral colour and odour, with one of the two predominant floral volatiles emitted by each subspecies being taxon-specific. Plant size was positively correlated with fruit set in most populations, whereas we found no apparent link between floral colour and female reproductive success. We detected positive selection on several taxon-specific compounds in A. coriophora subsp. fragrans, whereas no selection was found on floral volatiles of A. coriophora subsp. coriophora and A. coriophora subsp. martrinii. This study is one of the first to document variation in phenotypic selection exerted on floral scents among conspecific populations. Our results suggest that selection could contribute to ongoing chemical divergence among A. coriophora subspecies.
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Affiliation(s)
- Nina Joffard
- Centre d'Ecologie Fonctionnelle et Evolutive, EPHE-PSL, CNRS, Univ. Montpellier, Univ. Paul Valéry Montpellier 3, IRD, Montpellier, France
- Evolutionsbiologiskt Centrum (EBC), Uppsala, Sweden
| | - Iris Le Roncé
- Centre d'Ecologie Fonctionnelle et Evolutive, EPHE-PSL, CNRS, Univ. Montpellier, Univ. Paul Valéry Montpellier 3, IRD, Montpellier, France
- Département de biologie, École Normale Supérieure de Lyon, Lyon, France
| | - Alban Langlois
- Centre d'Ecologie Fonctionnelle et Evolutive, EPHE-PSL, CNRS, Univ. Montpellier, Univ. Paul Valéry Montpellier 3, IRD, Montpellier, France
- Université Toulouse III Paul Sabatier, Toulouse, France
| | - Julien Renoult
- Centre d'Ecologie Fonctionnelle et Evolutive, EPHE-PSL, CNRS, Univ. Montpellier, Univ. Paul Valéry Montpellier 3, IRD, Montpellier, France
| | - Bruno Buatois
- Centre d'Ecologie Fonctionnelle et Evolutive, EPHE-PSL, CNRS, Univ. Montpellier, Univ. Paul Valéry Montpellier 3, IRD, Montpellier, France
| | - Laurent Dormont
- Centre d'Ecologie Fonctionnelle et Evolutive, EPHE-PSL, CNRS, Univ. Montpellier, Univ. Paul Valéry Montpellier 3, IRD, Montpellier, France
| | - Bertrand Schatz
- Centre d'Ecologie Fonctionnelle et Evolutive, EPHE-PSL, CNRS, Univ. Montpellier, Univ. Paul Valéry Montpellier 3, IRD, Montpellier, France
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Joffard N, Legendre L, Gibernau M, Pascal L. Differential Accumulation of Volatile Organic Compounds by Leaves and Roots of Two Guianese Philodendron Species, P. fragrantissimum Kunth and P. melinonii Brongn. Chem Biodivers 2016; 14. [PMID: 28027618 DOI: 10.1002/cbdv.201600415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 12/23/2016] [Indexed: 11/10/2022]
Abstract
Leaf and root essential oils of two closely related but ecologically distant Philodendron species were extracted in natural conditions in French Guiana and analysed by GC/MS to i) describe the blends of volatile organic compounds (VOCs) produced by those species and ii) analyse species and environment-based variations in extracts composition. A total of 135 VOCs were detected with a majority of aliphatic sesquiterpenes. P. fragrantissimum produced mainly β-bisabolene (on average 29.12% of the extract) as well as α- and β-selinene (14.52% and 17.50%, respectively) while in P. melinonii, four aliphatic sesquiterpenes could alternatively be the main component: (E)-β-farnesene (up to 91.42% of the extract), germacrene-D (73.74%), β-caryophyllene (51.63%) and trans-α-bergamotene (41.26%). A significant effect of species and organs on extracts composition was observed while the environment (sun exposure) only affected the relative proportions of monoterpenes and sesquiterpenes in roots of P. melinonii. These results are discussed in the light of the potential role of leaf and root terpenes in Philodendron species.
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Affiliation(s)
- Nina Joffard
- UMR CNRS 5175, Centre d'Ecologie Fonctionnelle et Evolutive, 1919 route de Mende, FR-34293, Montpellier
| | - Laurent Legendre
- Université de Lyon, 43 Boulevard du 11 Novembre 1918, F-69622, Lyon, France.,Université Lyon 1, Villeurbanne, France.,CNRS, UMR5557, Ecologie Microbienne, Villeurbanne, France.,INRA, UMR1418, Villeurbanne, France
| | - Marc Gibernau
- SPE UMR 6134, Natural Resources Project - Vignola, CNRS - University of Corsica, Route des sanguinaires, FR-20000, Ajaccio
| | - Laurence Pascal
- UMR 186, Interactions Plantes Microorganismes Environnement, Université de Montpellier, 911 avenue agropolis - BP 64501, FR-34394, Montpellier Cedex 5
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Joffard N, Buatois B, Schatz B. Integrative taxonomy of the fly orchid group: insights from chemical ecology. Naturwissenschaften 2016; 103:77. [DOI: 10.1007/s00114-016-1403-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 08/28/2016] [Accepted: 08/30/2016] [Indexed: 10/21/2022]
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