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Your search keyword '"Marquardt, Jeannine"' showing total 16 results
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16 results on '"Marquardt, Jeannine"'

1. Hybridisation in bluebells (Hyacinthoides spec.) using next-generation sequencing to reconstruct a natural hybrid zone in Spain

Author

Marquardt, Jeannine

Subjects
583, Bluebells, Hybridisation, Plant biology
Abstract

Hybridisation is a common evolutionary process that can arise in primary or secondary contact. Gene ow and/or reproductive isolation between hybridising taxa can be explored in hybrid zones. Therefore, a (homoploid) hybrid zone in north-west Spain between Hyacinthoides non-scripta and H. hispanica was studied. The centre occurs west to east across the Galicio-Duero Mountains with H. non-scripta distributed north, and H. hispanica south of the centre. The hybrids' genome sizes and phenotypes represented a range of intermediate states between their parents. Crossing and seed germination experiments revealed a low inter-speci c barrier, and the hybrids showed similarly good tness. Genome wide markers for large genome species were designed from transcriptomes. Diagnostic SNPs between H. non-scripta and H. hispanica were targeted and re-sequenced with multiplexing PCR. Coalescence analyses suggested a Pleistocene origin of parapatric speciation between H. non-scripta and H. hispanica. These results are supported by shared inter-speci c polymorphisms, the lack of recent hybrid generations and of parental individuals in sympatry. Di erential introgression patterns between the organellar and nuclear genomes revealed that formerly H. hispanica ranged further north but was swamped by H. non-scripta alleles. Asymmetric hybridisation was reasoned by absence of backcrosses between northern hybrids to H. non-scripta, but presence between southern hybrids and H. hispanica. Combining these results, a southwards movement of the hybrid zone centre caused by climate change (and adaptive introgression), or inter-speci c di erences in owering time was suggested. Cline patterns revealed cyto-nuclear incompatibilities, which could evolve through divergent adaptation of the organelle to climate and a delayed selection on nuclear inter-acting loci. Both species are in secondary contact in the UK due to recent introduction(s) of H. hispanica and garden variants, which is considered to cause genetic pollution of native H. non-scripta. Therefore, a conservation study is in progress, in which this diagnostic marker system for bluebells is applied.

Published
2017

6. Polyploidy does not control all: Lineage‐specific average chromosome length constrains genome size evolution in ferns

Author

Liu, Hong‐Mei, primary, Ekrt, Libor, additional, Koutecky, Petr, additional, Pellicer, Jaume, additional, Hidalgo, Oriane, additional, Marquardt, Jeannine, additional, Pustahija, Fatima, additional, Ebihara, Atsushi, additional, Siljak‐Yakovlev, Sonja, additional, Gibby, Mary, additional, Leitch, Ilia, additional, and Schneider, Harald, additional

Published
2019
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8. Neo- and Paleopolyploidy contribute to the species diversity of Asplenium -the most species-rich genus of ferns

Author

Schneider, Harald, Liu, Hong-Mei, Chang, Yan-Fen, Ohlsen, Daniel, Perrie, Leon R, Shepherd, Lara, Kessler, Michael, Karger, Dirk Nikolaus, Hennequin, Sabine, Marquardt, Jeannine, Russell, Stephen, Ansell, Stephen, Lu, Ngan Thi, Kamau, Peris, Lóriga, Josmaily, Regalado, Ledis, Heinrichs, Jochen, Ebihara, Atsushi, Smith, Alan R, Gibby, Mary, Dpt of Life Sciences [London], The Natural History Museum [London] (NHM), Museum of New Zealand - Te Papa Tongarewa, Institut für Systematische und Evolutionäre Botanik, Universität Zürich [Zürich] = University of Zurich (UZH), Institut de Systématique, Evolution, Biodiversité (ISYEB ), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Mayo Clinic [Rochester], Vietnam Academy of Science and Technology (VAST), Ludwig Maximilian University [Munich] (LMU), National Museum of Nature and Science, Imperial College Healthcare NHS Trust, University of Zurich, and Schneider, Harald

Subjects
10121 Department of Systematic and Evolutionary Botany, 1105 Ecology, Evolution, Behavior and Systematics, [SDV]Life Sciences [q-bio], 1110 Plant Science, 580 Plants (Botany), 10211 Zurich-Basel Plant Science Center
Abstract

International audience

Published
2017

10. Hybridisation between the British and the Spanish bluebell

Author

Marquardt, Jeannine, Leitch, Andrew, Nichols, Richard, and Schneider, Harald

Subjects
15. Life on land
Abstract

The native British bluebell, Hyacinthoides non-scripta, is a spring flowering lily, which is well- known in natural, old forests across the British Isles. In the 17th century another bluebell taxon from the Iberian Peninsula was introduced as an ornamental plant. Since the beginning of the last century there have been reports of it in the wild, and it has recently been found to form fully fertile hybrids with the native bluebell. Both hybrids and the alien taxa are spreading, yet that usually occurs close to urban areas probably because of garden escapes. Several surveys and studies looking into the distribution of these taxa have suggested they may be putting the native British bluebell at risk, by outcompeting and replacing them in their natural habitats. However, our understanding of environmental drivers influencing alien invasion is confused by human impact, including on-going plantings and changing land use. To better understand the dynamic between alien and native taxa, I study a natural hybrid zone between the British bluebell and its sister species, Hyacinthoides hispanica, in Spain, where there is minimal human influence. In this natural hybrid zone we learned from the hybrid’s flower morphologies and additional chloroplast data that the parents contribute symmetrically to the intermediate forms, and the hybrids appear without evident hybrid deficiencies. Gene flow is mainly mediated through pollen exchange, because clonal buds and seed dispersal are only important on an imminent range. We will use genome-wide markers to get an understanding of patterns of introgression across hundreds of loci.

Published
2015
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11. Neo- and Paleopolyploidy contribute to the species diversity ofAsplenium-the most species-rich genus of ferns

Author

Schneider, Harald, primary, Liu, Hong-Mei, additional, Chang, Yan-Fen, additional, Ohlsen, Daniel, additional, Perrie, Leon R., additional, Shepherd, Lara, additional, Kessler, Michael, additional, Karger, Dirk N., additional, Hennequin, Sabine, additional, Marquardt, Jeannine, additional, Russell, Stephen, additional, Ansell, Stephen, additional, Lu, Ngan Thi, additional, Kamau, Peris, additional, Lóriga, Josmaily, additional, Regalado, Ledis, additional, Heinrichs, Jochen, additional, Ebihara, Atsushi, additional, Smith, Alan R., additional, and Gibby, Mary, additional

Published
2017
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13. A molecular phylogeny of selligueoid ferns (Polypodiaceae): Implications for a natural delimitation despite homoplasy and rapid radiation.

Author

Lijuan He, Schneider, Harald, Hovenkamp, Peter, Marquardt, Jeannine, Ran Wei, Xueping Wei, Xianchun Zhang, and Qiaoping Xiang

Subjects
HOMOPLASY, POLYPODIACEAE, MOLECULAR phylogeny
Abstract

Homoplasy, autapomorphy and rapid radiation have frequently been discussed as the main causes of instable generic classifications of plants including ferns. In this study, we explore the natural generic classification for selligueoid ferns by investigating the phylogenetic relationships among almost all its previously recognized segregates. We compare the phylogenies that resulted from two datasets. Dataset 1 comprises a broad taxonomic sampling of fifty-one species of selligueoid ferns. Phylogenetic analysis of this dataset revealed a notable long branch followed by a polytomy recovering three core clades of selligueoid ferns. Only one of the core clades corresponds to the traditional generic concept of Arthromeris. Dataset 2 includes fewer species but a broader sample of six plastid DNA markers. However, the results of this dataset show that the increase of informative molecular characters still did not provide sufficient evidence to resolve the polytomy. The long branches together with a consistent backbone polytomy support a rapid radiation in the selligueoid ferns. The majority of morphological characters were recovered as homoplastic, which hampers the identification of segregates with unambiguous diagnostic characters. Considering morphological characters and our molecular phylogeny, a single genus Selliguea s.l., which includes all selligueoid species, is proposed here to achieve taxonomic stability in this group. [ABSTRACT FROM AUTHOR]

Published
2018
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