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trié(s) par (Pertinence décroissant(e), Titre croissant(e)) Affiner la recherche Générer le flux rss de la rechercheGenetic diversity of the declining arable plant Centaurea cyanus : population fragmentation within an agricultural landscape is not associated with enhanced spatial genetic structure / Valérie Le Corre in Weed research, vol. 54, n°5 (Année 2015)
Titre : Genetic diversity of the declining arable plant Centaurea cyanus : population fragmentation within an agricultural landscape is not associated with enhanced spatial genetic structure Type de document : Livre Auteurs : Valérie Le Corre, Auteur ; Solène Bellanger, Auteur ; Jean-Philippe Guillemin, Auteur ; Henri Darmency, Auteur Année de publication : 2015 Article en page(s) : pp. 436-444 Langues : Français Catégories : [Espèces (in biblio)] Centaurea cyanus Mots-clés : caractérisation génétique plante messicole Résumé : "Agricultural intensification has recently resulted in the decrease in frequency and abundance of arable weed species. This includes the previously widespread Centaurea cyanus, whose populations are now fragmented and infrequent in western Europe. The consequences of habitat modification and fragmentation in terms of genetic diversity of the remaining populations have not yet been addressed. We used ten microsatellite markers to assess the genetic diversity and genetic structure of populations contained in an agricultural landscape in north‐eastern France. The ten microsatellites were all highly polymorphic. Centaurea cyanus appears to be a genetically variable species, with high levels of genetic diversity within each cultivated field. Genetic structure was investigated using a Bayesian method. The partitioning of the genetic variation into three clusters was not associated with sampling locations, and most individuals were admixed. These results suggest that the cornflower populations investigated may have multiple origins in the past and that genetic variation has been reshuffled by human transportation of seeds. Thus, anthropogenic dispersal associated with farming activities is probably a major factor driving the structure of genetic diversity in arable land plants. Despite low levels of genetic differentiation between populations, fine‐scale spatial genetic structure was observed within populations, suggesting limited local dispersal. We conclude that in areas where C. cyanus has become rare, the recent fragmentation of populations may in the future cause a loss of genetic diversity and even extinction." (source : auteurs) Type de publication : périodique Référence biblio : Le Corre V., Bellanger S., Guillemin J.-P., Darmency H., 2015 - Genetic diversity of the declining arable plant Centaurea cyanus : population fragmentation within an agricultural landscape is not associated with enhanced spatial genetic structure. Weed research, 54 (5) : 436-444. ID PMB : 69100 DOI : 10.1111/wre.12087 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=69100
in Weed research > vol. 54, n°5 (Année 2015) . - pp. 436-444[article]Exemplaires
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Titre : Variation of inbreeding depression in Centaurea cyanus L., a self-incompatible species Type de document : Livre Auteurs : Solène Bellanger, Auteur ; Jean-Philippe Guillemin, Auteur ; Solène Touzeau, Auteur ; Henri Darmency, Auteur Année de publication : 2012 Article en page(s) : pp. 24–29 Langues : Anglais Catégories : [Espèces (in biblio)] Centaurea cyanus Mots-clés : plante messicole caractérisation génétique Résumé : "tThe evolutionary trajectory of isolated or small populations of self-incompatible species depends ongenetic variation in the capacity to transition to self-compatibility and the impact of inbreeding onplant fitness. Centaurea cyanus is an example of a self-incompatible, arable field-dependent weed speciesthat is in regression in western Europe due to agricultural intensification. However, some cases of self-fertilization have been observed. Here, we investigated how inbreeding depression impacts the plantsby studying two generations of self-fertilized families. As early as at the stage of the first selfing genera-tion, we observed reduction in the number of florets per capitulum. By the second selfing generation, weobserved reductions in germination rate, plant height, above-ground plant biomass, seed set and the finalnumber and mass of seeds per plant. In particular, dramatically lower germination rate and reduced seedset contributed to a low cumulative fitness index of the generations that resulted from selfing. Never-theless, although high average inbreeding depression was observed, large variation in cumulative fitnessamong families would allow some of these selfed families to persist and trigger evolution of selfing insmall, isolated populations." (source : auteurs) Type de publication : périodique Référence biblio : Bellanger S., Guillemin J.-P., Touzeau S., Darmency H., 2012 - Variation of inbreeding depression in Centaurea cyanus L., a self-incompatible species. Flora, 212 : 24–29. ID PMB : 69099 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=69099
in Flora > vol. 212 (Année 2012) . - pp. 24–29[article]Exemplaires
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