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Temperature effects on dormancy levels and germination in temperate forest sedges (Carex) / Markus Brändel in Plant ecology, vol. 176 (Année 2005)

Public [article]  inPlant ecology > vol. 176 (Année 2005) . - pp. 245-261 Titre : Temperature effects on dormancy levels and germination in temperate forest sedges (Carex) Type de document : texte imprimé Auteurs : Markus Brändel, Auteur ; Wolfgang Schütz, Auteur Année de publication : 2005 Article en page(s) : pp. 245-261 Langues : Anglais (eng) Catégories : [Espèces (in biblio)] Carex pendula [Espèces (in biblio)] Carex remota [Thèmes] Dormance des graines Mots-clés : niche de régénération  températures de seuil Résumé : "The effects of stratification temperatures and burial in soil on dormancy levels of Carex pendula L. and C. remota L., two spring-germinating perennials occurring in moist forests, were investigated. Seeds buried for 34 months outdoors, and seeds stratified in the laboratory at temperatures between 3 and 18 °C for periods between 2 and 28 weeks, were tested over a range of temperatures. Seeds of the two species responded similarly to stratification treatments, except for an absolute light requirement in C. pendula. Primary dormancy was alleviated at all stratification temperatures, but low temperatures were more effective than higher ones . (≥ 12 °C). Dormancy induction in non-dormant seeds kept at 5 °C occurred when seeds were subsequently exposed to 18 °C. Dormancy was not induced by a transfer to lower temperatures. Buried seeds of both species exhibited seasonal dormancy cycles with high germination from autumn to spring and low germination during summer. Temperatures at which the processes of dormancy relief and of dormancy induction occurred, overlapped to a high degree. Whether, and when, dormancy changes occurred depended on test conditions. The lower temperature limit for germination (> 10%) was 9 °C in C. remota and 15 °C in C. pendula. Germination ceased abruptly above 36 °C. Germination requirements and dormancy patterns suggest regeneration from seed in late spring and summer at disturbed, open sites (forest gaps) and the capability to form long, persistent seed banks in both species." (source : auteurs) Type de publication : périodique Référence biblio : Brändel M., Schütz W., 2005 - Temperature effects on dormancy levels and germination in temperate forest sedges (Carex). Plant ecology, 176 : 245-261. ID PMB : 68938 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=68938 [article]

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The effect of stratification temperatures on the level of dormancy in primary and secondary dormant seeds of two Carex species / Markus Brändel in Plant ecology, vol. 178 (Année 2005)

Public [article]  inPlant ecology > vol. 178 (Année 2005) . - pp. 163-169 Titre : The effect of stratification temperatures on the level of dormancy in primary and secondary dormant seeds of two Carex species Type de document : texte imprimé Auteurs : Markus Brändel, Auteur Année de publication : 2020 Article en page(s) : pp. 163-169 Langues : Anglais (eng) Catégories : [Espèces (in biblio)] Carex pendula [Espèces (in biblio)] Carex remota [Espèces (in biblio)] Cyperaceae [Thèmes] Dormance des graines [Thèmes] Germination des graines Résumé : "The effect of temperature on the level of dormancy of primary and secondary dormant Carex pendula and Carex remota seeds was investigated. Primary dormant and secondary dormant seeds were stratified for 4 weeks at 5, 11, 13, and 15 °C, respectively, and tested for germination at 15/5 °C in light. To obtain secondary dormant seeds, primary dormant seeds were stratified at 5 °C and afterwards at 25 °C for 4 weeks. Germination tests were carried out in water and in 25 μmol KNO3-solution to examine differences in sensitivity to nitrate between seeds relieved from primary and secondary dormancy. In both species, seeds with primary and with induced secondary dormancy showed no significant differences in germination. The two sedges showed significant differences in the effect of stratification temperatures between primary and secondary dormant seeds. Primary dormant seeds of C. pendula showed high germination (>80%) in nitrate-solution after stratification at all temperatures, while only temperatures of 5, 11, and 13 °C led to higher germination in nitrate-solution in secondary dormant seeds. Germination percentages of primary and of secondary dormant C. pendula seeds in water increased to a higher extent only after stratification at 5 and 11 °C; stratification of 11 °C was more effective in secondary than in primary dormant seeds. The only temperature that relieved primary dormancy in C. remota seeds was 5 °C where germination in water and nitrate-solution was >90%. Germination of secondary dormant seeds was increased by stratification at 11 °C independent of the test solution but higher germination after stratification at 13 °C occurred only in nitrate-solution. The results support the existence of physiological differences in the regulation of primary and secondary dormancy by temperature, and in the reaction of nitrate, at least in C. remota." (source : auteur) Type de publication : périodique Référence biblio : Brändel M., 2020 - The effect of stratification temperatures on the level of dormancy in primary and secondary dormant seeds of two Carex species. Plant ecology, 178 : 163-169. ID PMB : 68940 DOI : s11258-004-3037-y Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=68940 [article]

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