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Reproductive characteristics of neophytes in the Czech Republic: traits of invasive and non-invasive species / Lenka Moracova in Preslia, 82 (2010) 

Public Citation [article]  inPreslia > 82 (2010) . - 365-390 Titre : Reproductive characteristics of neophytes in the Czech Republic: traits of invasive and non-invasive species Type de document : Électronique Auteurs : Lenka Moracova ; Petr Pyšek ; Vojtěch Jarošík (1958-2013) ; Vendula Havlíčková ; Petr Zákravský Année de publication : 2010 Article en page(s) : 365-390 Langues : Français (fre) Catégories : [CBNPMP-Thématique] Plantes subspontanées, naturalisées, envahissantes [CBNPMP-Géographique] Europe centrale Résumé : This paper describes the reproductive characteristics of 93 neophytes (alien species introduced after 1500 A.D.) of the flora of the Czech Republic and compares trait values between naturalized invasive and naturalized non-invasive neophytes. Species were sampled and seed collected in the field from multiple localities in the Czech Republic. Traits related to seed production (propagule number per plant and per population), dispersal (propagule size, length/width ratio and weight; buoyancy; epizoochory; terminal velocity) and establishment (germination; seedling relative growth rate; seedling establishment) were measured for each species either in the field, in a common garden experiment or in the laboratory. Invasive species significantly differ from naturalized non-invasive species in propagule length/width ratio (by having lower ratio, i.e. more rounded propagules) and fecundity (invasive species are more fecund, both per individual plant and in terms of the population propagule production). Invasive species have proportionally fewer seedlings establishing in the autumn and better capacity for dispersal by wind than non-invasive species. The results for several traits differ depending on whether or not the effect of phylogeny is included in analytical models. Considering species relatedness expressed as a taxonomic hierarchy, invasive species have lighter propagules and higher population propagule numbers, and marginally significantly differ in producing more propagules per plant and having higher capacity for dispersal bywater.We found that most variation in invasiveness is linked to variation among species within genera. This distribution of relatedness means that predictions of whether a species will become invasive cannot be based on traits of the relatives of the given species at higher taxonomic levels. The distinction made in this paper, i.e. invasive species vs. naturalized but non-invasive species, can potentially contribute to a deeper understanding of the role of traits associated with invasiveness because the crucial transition from the naturalized to invasion stage is rarely addressed in invasion ecology. Permalink : https://biblio.cbnpmp.fr/index.php?lvl=notice_display&id=153336 Moracova, Lenka, Pyšek, Petr, Jarošík, Vojtěch (1958-2013), Havlíčková, Vendula, Zákravský, Petr 2010 Reproductive characteristics of neophytes in the Czech Republic: traits of invasive and non-invasive species. Preslia, 82: 365-390.

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Consultable article (2010) URL

Seasonal pattern of germination and seed longevity in the invasive species Heracleum mantegazzianum / Lenka Moracova in Preslia, 78 (2006) 

Public Citation [article]  inPreslia > 78 (2006) . - 287-301 Titre : Seasonal pattern of germination and seed longevity in the invasive species Heracleum mantegazzianum Type de document : Électronique Auteurs : Lenka Moracova ; Petr Pyšek ; Jan Pergl (1977-) ; Irena Perglova ; Vojtěch Jarošík (1958-2013) Année de publication : 2006 Article en page(s) : 287-301 Langues : Anglais (eng) Catégories : [CBNPMP-Thématique] Plantes subspontanées, naturalisées, envahissantes [CBNPMP-Géographique] République Tchèque Mots-clés : Heracleum mantegazzianum Sommier & Levier Résumé : We investigated the effects of different temperature regimes and dry storage on germination of H. mantegazzianum (Apiaceae, native to Caucasus) seeds in the laboratory and linked the results with studies of seasonal seed bank depletion in a common garden experiment and under field conditions. Seeds were collected at seven sites in the Slavkovský les region, Czech Republic, cold-stratified for 2 months and germinated at seven temperature regimes. Under all temperature regimes, fresh seeds germinated to significantly higher percentages than older (1, 2, 3 years) seeds. For all storage lengths, seeds germinated best at alternating day/night temperatures of 20/5 °C. The length of the germination period had a significant effect only at low constant temperatures of 2 and 6 °C, where germination percentage increased between 2 and 6 months. Seasonal germination exhibited a distinct pattern, with rapid depletion of seed bank by the first spring after seed burial. Non-dormant seeds were present in the soil early in spring and late in autumn. The higher summer temperatures prevented dormancy breaking and another cold period of at least two months below 10 °C was needed to bring non-germinated seeds out of dormancy. The results suggest that (1) seed dormancy of H. mantegazzianum was not completely broken until the first spring, but that some seeds re-enter or retain dormancy during high summer temperatures and that (2) the threshold needed for breaking the dormancy was achieved gradually during the cold autumn and winter months. However, in a small fraction of seeds the dormancy breaking process took several years. Of seeds buried in 10 different regions of the Czech Republic, on average 8.8% survived 1 year, 2.7% 2 years and 1.2% remained viable and dormant after 3 years of burial. The ability of even small fraction of H. mantegazzianum seeds to survive for at least 3 years can result in re-invasion of this species into controlled sites. Permalink : https://biblio.cbnpmp.fr/index.php?lvl=notice_display&id=142012 Moracova, Lenka, Pyšek, Petr, Pergl, Jan (1977-), Perglova, Irena, Jarošík, Vojtěch (1958-2013) 2006 Seasonal pattern of germination and seed longevity in the invasive species Heracleum mantegazzianum. Preslia, 78: 287-301.

Documents numériques

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