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Polyploid evolution : The ultimate way to grasp the nettle / Ludmila Rejlová in PloS ONE, vol. 14, n°7 (Année 2019)

Public [article]  inPloS ONE > vol. 14, n°7 (Année 2019) . - e0218389 Titre : Polyploid evolution : The ultimate way to grasp the nettle Type de document : texte imprimé Auteurs : Ludmila Rejlová, Auteur ; Jindrch Chrtek, Auteur ; Pavel Travnicek, Auteur ; Magdalena Lucanová (Lu%u010Danová, Magdalena), Auteur Année de publication : 2019 Article en page(s) : e0218389 Langues : Anglais (eng) Catégories : [Espèces (in biblio)] Urtica [Espèces (in biblio)] Urtica dioica [Thèmes] Taxonomie Mots-clés : polyploïdie  cytométrie en flux  caryologie  écologie végétale  bioclimatologie  cytogéographie Résumé : "Polyploidy is one of the major forces of plant evolution and widespread mixed-ploidy species offer an opportunity to evaluate its significance. We therefore selected the cosmopolitan species Urtica dioica (stinging nettle), examined its cytogeography and pattern of absolute genome size, and assessed correlations with bioclimatic and ecogeographic data (latitude, longitude, elevation). We evaluated variation in ploidy level using an extensive dataset of 7012 samples from 1317 populations covering most of the species' distribution area. The widespread tetraploid cytotype (87%) was strongly prevalent over diploids (13%). A subsequent analysis of absolute genome size proved a uniform Cx-value of core U. dioica (except for U. d. subsp. cypria) whereas other closely related species, namely U. bianorii, U. kioviensis and U. simensis, differed significantly. We detected a positive correlation between relative genome size and longitude and latitude in the complete dataset of European populations and a positive correlation between relative genome size and longitude in a reduced dataset of diploid accessions (the complete dataset of diploids excluding U. d. subsp. kurdistanica). In addition, our data indicate an affinity of most diploids to natural and near-natural habitats and that the tetraploid cytotype and a small part of diploids (population from the Po river basin in northern Italy) tend to inhabit synanthropic sites. To sum up, the pattern of ploidy variation revealed by our study is in many aspects unique to the stinging nettle, being most likely first of all driven by the greater ecological plasticity and invasiveness of the tetraploid cytotype." (source : auteurs) Type de publication : périodique Référence biblio : Rejlová L., Chrtek J., Travnicek P., Lucanová M., 2019 - Polyploid evolution : The ultimate way to grasp the nettle. PloS ONE, 14 (7) : e0218389. ID PMB : 71286 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=71286 [article]

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Stellaria ruderalis, a new species in the Stellaria mediagroup from central Europe / Martin Lepsí in Preslia, vol. 91 (Année 2019)  

Public [article]  inPreslia > vol. 91 (Année 2019) . - pp. 391-420 Titre : Stellaria ruderalis, a new species in the Stellaria mediagroup from central Europe Type de document : texte imprimé Auteurs : Martin Lepsí (Lepší, Martin), Auteur ; Petr Lepsí (Lepší, Petr), Auteur ; Petr Koutecky, Auteur ; Magdalena Lucanová (Lu%u010Danová, Magdalena), Auteur ; Eva Koutecká, Auteur ; Zdenek Kaplan, Auteur Année de publication : 2019 Article en page(s) : pp. 391-420 Langues : Anglais (eng) Catégories : [Espèces (in biblio)] Stellaria [ZG] Europe centrale [Thèmes] Taxonomie Mots-clés : Stellaria ruderalis  cytométrie  Internal transcribed spacer (ITS)  caryologie  morphométrie multivariée Résumé : "A new allotetraploid species in the Stellaria media group, S. ruderalis M. Lepší, P. Lepší, Z. Kaplan & P. Koutecký, which is possibly of hybridogenous origin between S. pallida and S. neglecta, is distinguished and described based on a biosystematic revision of the S. media group. A suite of biosystematic techniques, including molecular (internal transcribed spacer sequencing), karyological (chromosome counting, flow cytometry), multivariate morphometrics and phenological observations, was used to assess the variation in this species group and determine the taxonomic status of the species. All the methods employed produced similar results and supported the delimitation of four species within the Stellaria media group in central Europe: Stellaria ruderalis (2n = 4x = 44), S. pallida (2n = 2x = 22), S. neglecta (2n = 2x = 22) and S. media s. str. (2n = 4x = 40). Stellaria ruderalis is a winter annual growing mainly in disturbed ruderal open or semi-open communities. This species’ broad ecological amplitude allows it to commonly co-occur with its three related species. It is probably a widespread species in southern and central Europe. It is currently spreading in the northern part of central Europe. Photographs of the type specimen and individuals of the new species in situ are presented. Scanning electron micrographs of seeds, microphotographs of seeds and mitotic chromosome spreads and a key for the identification of all four species are provided." (source : auteurs) Type de publication : périodique Référence biblio : Lepsí M., Lepsí P., Koutecky P., Lucanová M., Koutecká E., Kaplan Z., 2019 - Stellaria ruderalis, a new species in the Stellaria mediagroup from central Europe. Preslia, 91 : 391-420. ID PMB : 69010 DOI : 10.23855/preslia.2019.391 En ligne : http://www.preslia.cz/doi/preslia.2019.391.html Format de la ressource électronique : document Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=69010 [article]

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