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Cytogenetic, geographical, spore type and plastid haplotype data reveal cryptic patterns of species diversity in the cosmopolitan Cystopteris fragilis complex (Polypodiopsida: Cystopteridaceae) / Libor Ekrt in Botanical Journal of the Linnean Society, vol. 199, n°3 (Année 2022)

Public [article]  inBotanical Journal of the Linnean Society > vol. 199, n°3 (Année 2022) . - pp. 728-739 Titre : Cytogenetic, geographical, spore type and plastid haplotype data reveal cryptic patterns of species diversity in the cosmopolitan Cystopteris fragilis complex (Polypodiopsida: Cystopteridaceae) Type de document : texte imprimé Auteurs : Libor Ekrt, Auteur ; Jiri Kosnar, Auteur ; Carl J. Rothfels, Auteur ; Kristýna HanuÅ¡ová (Hanusova), Auteur ; Ondřej Hornych, Auteur ; Tomas Urfus, Auteur Année de publication : 2022 Article en page(s) : pp. 728-739 Langues : Anglais (eng) Catégories : [Espèces (in biblio)] Cystopteris dickieana [Espèces (in biblio)] Cystopteris fragilis [Thèmes] Ptéridophytes (fougère, prêle, lycopode, isoète, sélaginelle) [Thèmes] Taxonomie Mots-clés : cytogénétique, cytotaxonomie  hybridation  polyploïdie  Spore  ADN chloroplastique  phylogénétique Résumé : "The delimitation of lineages in the Cystopteris fragilis complex is complicated by the presence of multiple cytotypes and a lack of defining morphological characters. One character, the production of rugose instead of regular spiny spores, is sometimes associated with a potential Scottish endemic, C. dickieana; however, whether this character is associated with a distinct lineage is uncertain. To better understand the diversity in the C. fragilis complex, we selected 87 C. fragilis samples of known ploidy (4x, 5x, 6x) for sequencing of two plastid loci and we assessed their spore types. These samples represent the variability found in Northern Hemisphere populations, including the type locality of C. dickieana in Scotland. Our analyses revealed two haplotype lineages, which we label the hemifragilis and reevesiana clades, based on their potential relationship to the two presumed diploid parents of C. fragilis. Hexaploids and tetraploids were both polyphyletic. Rugose spores were rarer overall (26% of samples), but five times more prevalent in the hemifragilis clade. Although proper delimitation and understanding of C. fragilis remains a challenge, this study further describes great genotypic and cytotypic complexity present in this complex. Furthermore, rugose-spored plants are widely distributed and should not be associated with a single name." (source : auteurs) Type de publication : périodique Référence biblio : Ekrt L., Kosnar J., Rothfels C., HanuÅ¡ová K., Hornych O., Urfus T., 2022 - Cytogenetic, geographical, spore type and plastid haplotype data reveal cryptic patterns of species diversity in the cosmopolitan Cystopteris fragilis complex (Polypodiopsida: Cystopteridaceae). Biological Journal of the Linnean Society, 199 (3) : 728-739. ID PMB : 71474 DOI : 10.1093/botlinnean/boab078 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=71474 [article]

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The ecological significance of sexual reproduction in peat mosses (Sphagnum) / Sebastian Sundberg (2000)  

Public Titre : The ecological significance of sexual reproduction in peat mosses (Sphagnum) Type de document : texte imprimé Auteurs : Sebastian Sundberg, Auteur Editeur : Acta Universitatis Upsaliensis Année de publication : 2000 Collection : Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology num. 581 Importance : 37 p. ISBN/ISSN/EAN : 91-554-4847-X Langues : Anglais (eng) Mots-clés : colonisation  perturbation  expérience  longévité  spore  bryophyte Résumé : "Peat mosses (Sphagnum) are widely distributed and are a major component of mire vegetationand peat throughout the boreal and temperate regions. Most boreal Sphagnum species regu-larly produce sporophytes, but the ecological role of the spore has been questioned. This studyshows that the spores can form a spore bank and have the ability to germinate and contributeto moss establishment whenever suitable conditions occur. The results suggest that spore pro-duction is important for explaining the wide distribution and omnipresence of Sphagnum innutrient-poor wetlands. The results further imply that initial recruitment from spores predomi-nates in Sphagnum after disturbance or formation of suitable habitats.A series of experiments showed that addition of phosphorus-containing substrates, suchas fresh plant litter or moose dung, resulted in spore establishment on bare, moist peat. A fieldexperiment indicated establishment rates of about 1% of sown, germinable spores on peatwith added substrates. Plant litter on moist soil, without a closed cover of bryophytes, is animportant safe site for the establishment of Sphagnum spores. The results fit the observed pat-tern of colonisation by Sphagnum beneath Eriophorum vaginatum tussocks in mires severelydisturbed by peat extraction. Successful long-distance dispersal was indicated by the occur-rence of several regionally new or rare Sphagnum species in disturbed mires.Spore number per sporophyte ranged among Sphagnum species from 18 500 to 240 000,with a trade-off between spore number and spore size. Annual spore production was estimatedat 15 million spores per square metre on two investigated mires. Sporophyte productionshowed a large interannual variation. Sporophyte production was positively related to theamount of precipitation the preceding summer. This was probably because a high water levelpromoted gametangium formation. Spore dispersal occurred in July and August. The earliertiming of spore dispersal in the more drought-sensitive, hollow-inhabiting sphagna should re-duce the risk of sporophytes drying out prematurely during summer droughts.Spores kept refrigerated up to 13 years retained high germinability. A field experimentshowed that Sphagnum can form a persistent spore bank, with a potential longevity of severaldecades." (source : auteur) Type de publication : livre Référence biblio : Sundberg S., [s. d.] - The ecological significance of sexual reproduction in peat mosses (Sphagnum). Acta Universitatis Upsaliensis, 37 p. (Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology ; 581). En ligne : http://www.diva-portal.org/smash/get/diva2:166017/FULLTEXT01.pdf Format de la ressource électronique : document Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=66027

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Notes on North American Sphagnum, XIII. Sphagnum pylaesii / A. Leroy in The Bryologist, vol. 64, n°2-3 (Eté - Automne 1961)

Public [article]  inThe Bryologist > vol. 64, n°2-3 (Eté - Automne 1961) . - pp. 208-214 Titre : Notes on North American Sphagnum, XIII. Sphagnum pylaesii Type de document : texte imprimé Auteurs : A. Leroy, Auteur Année de publication : 1961 Article en page(s) : pp. 208-214 Langues : Anglais (eng) Mots-clés : Hyalin  cellule de plante  spore  stomate  Solar fibrils  Explosives  Spore discharge  Chlorophylls  Sporophytes  Coasts Type de publication : périodique Référence biblio : Leroy A., 1961 - Notes on North American Sphagnum, XIII. Sphagnum pylaesii. The Bryologist, 64 : 208-214. Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=66081 [article]

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Survival of Chlorophyllous and Nonchlorophyllous Fern Spores through Exposure to Liquid Nitrogen / Valerie Pence in American Fern Journal, vol. 90, n°4 (Année 2000)

Public [article]  inAmerican Fern Journal > vol. 90, n°4 (Année 2000) . - pp. 119-126 Titre : Survival of Chlorophyllous and Nonchlorophyllous Fern Spores through Exposure to Liquid Nitrogen Type de document : texte imprimé Auteurs : Valerie Pence, Auteur Année de publication : 2000 Article en page(s) : pp. 119-126 Langues : Anglais (eng) Mots-clés : germination des spores  spore  fougère  viabilité des graines  cryopréservation  plante menacée Résumé : "Thirty-three species of ferns with nonchlorophyllous spores and five species with chlorophyllous spores were studied in regard to their ability to survive exposure to liquid nitrogen (LN). Air dried spores showed no inhibition of germination after LN exposure when planted on soil or growth medium. Spores of three species that were stored for 75 months either at 4°C, -20°C, or in LN showed no decrease in viability over that time, and spores of four other species were maintained successfully for 52 months in LN. Fresh chlorophyllous spores that were air dried, dried over silica gel, or prepared with the encapsulation dehydration procedure also showed good survival through desiccation and LN exposure. Spores of Osmunda regalis germinated well after 18 months of LN storage. These results indicate that both nonchlorophyllous and chlorophyllous spores are candidates for long-term germplasm storage at low temperatures, including storage in LN." Type de publication : périodique Référence biblio : Pence V., 2000 - Survival of Chlorophyllous and Nonchlorophyllous Fern Spores through Exposure to Liquid Nitrogen. American Fern Journal, 90 (4) : 119-126. DOI : 10.2307/1547488 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=67599 [article]

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On the typification of three Isoetes names (Isoetaceae, Lycopodiopsida) described from France / Michel Boudrie in Phytotaxa, vol. 641, n°4 (Année 2024)

Public [article]  inPhytotaxa > vol. 641, n°4 (Année 2024) . - pp. 286-294 Titre : On the typification of three Isoetes names (Isoetaceae, Lycopodiopsida) described from France Auteurs : Michel Boudrie, Auteur ; Germinal Rouhan, Auteur ; Valéry Malécot, Auteur ; Angelo Troia, Auteur Année de publication : 2024 Article en page(s) : pp. 286-294 Langues : Anglais (eng) Catégories : [ZG] France [Espèces (in biblio)] Isoëtes delalandei [Espèces (in biblio)] Isoëtes echinospora [Espèces (in biblio)] Isoëtes tenuissima Mots-clés : typification  lectotype  spore  microscopie électronique à balayage (SEM) Résumé : "This paper deals with typification of three species names in Isoetes described from France: the lectotype previously designated for I. delalandei J.Lloyd is here superseded by another lectotype according to new evidence, and lectotypes are designated for I. echinospora Durieu and I. tenuissima Boreau. Selected specimens are preserved at ANG for I. delalandei, and at P for the two others. Scanning Electron Microscope (SEM) images of the spores, known to provide important routine characters in Isoetes, were acquired from the types, and information about the loci classici are provided. Isoetes echinospora and I. tenuissima have currently disappeared from their loci classici." (source : auteurs) Type de publication : périodique Référence biblio : Boudrie M., Rouhan G., Malécot V., Troia A., 2024 - On the typification of three Isoetes names (Isoetaceae, Lycopodiopsida) described from France. Phytotaxa, 641 (4) : 286-294. ID PMB : 71827 DOI : 10.11646/phytotaxa.641.4.5 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=71827 [article]

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The genus Huperzia (Lycopodiaceae) in the Azores and Madeira / José Antonio Fernández Prieto in Botanical Journal of the Linnean Society, vol. 158 (Année 2008)

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