Search results for "Ragweed"
showing 10 items of 15 documents
Invasive and native populations of common ragweed exhibit strong tolerance to foliar damage.
2013
8 pages; International audience; Tolerance and resistance are defence strategies evolved by plants to cope with damage due to herbivores. The introduction of exotic species to a new biogeographical range may alter the plant herbivore interactions and induce selection pressures for new plant defence strategies with a modified resource allocation. To detect evolution in tolerance to herbivory in common ragweed, we compared 3 native (North America) and 3 introduced (France) populations, grown in a common garden environment. We explored the effect of leaf herbivory on plant vegetative and reproductive traits. Plants were defoliated by hand, simulating different degrees of insect grazing by remo…
Eight microsatellite markers isolated from common ragweed (Ambrosia artemisiifolia L.) and cross-amplification with herbarium specimens
2009
; Eight microsatellite markers were developed for population genetic analyses of the common ragweed, Ambrosia artemisiifolia. Markers were tested for amplification with three populations (two recent populations from France and North America, and one historical population from herbarium specimens). These loci revealed a high level of genetic variability (5-19 alleles per locus; expected heterozygosity, 0.48-0.92). No significant deviation from Hardy-Weinberg equilibrium and no linkage disequilibrium were observed. The data thus demonstrate their utility as efficient genetic markers for determining the genetic diversity, population differentiation, and gene flow among invasive, native, and h…
Evolution of herbicide resistance in mugwort (Ambrosia artemisiifolia L.): search for genetic determinisms and application to molecular diagnosis
2022
Common ragweed (Ambrosia artemisiifolia L.), a particularly troublesome and allergenic weed, is mainly controlled in agricultural fields using ALS inhibitor herbicides. Recent cases of herbicide resistance have been reported in France and are jeopardising the efficacy of this mode of action. Both target site resistance (TSR, structural mutation in ALS gene) and non target site resistance (NTSR, regulatory and/or structural mutations in secondary metabolism) are involved. The fundamental aim of this work was to identify the genetic determinisms of resistance to ALS inhibitors that have evolved in common ragweed populations in France. As an applied objective, this work also aimed to prepare t…
Evolution of common ragweed (Ambrosia artemisiifolia) resistance to herbicides : identification of genetic determinisms and application to molecular …
2022
Common ragweed (Ambrosia artemisiifolia L.), a particularly troublesome and allergenic weed, is mainly controlled in agricultural fields using ALS inhibitor herbicides. Recent cases of herbicide resistance have been reported in France and are jeopardising the efficacy of this mode of action. Both target site resistance (TSR, structural mutation in ALS gene) and non target site resistance (NTSR, regulatory and/or structural mutations in secondary metabolism) are involved. The fundamental aim of this work was to identify the genetic determinisms of resistance to ALS inhibitors that have evolved in common ragweed populations in France. As an applied objective, this work also aimed to prepare t…
Predicting the potential global range of common ragweed (Ambrosia artemisiifolia) using biologically informed and correlative species distribution mo…
2012
National audience
Introduction et dispersion d'une espèce envahissante : le cas de l'ambroisie à feuilles d'armoise (Ambrosia artemisiifolia L.) en France
2011
National audience; Ambrosia artemisiifolia L. (common ragweed) was accidentally introduced into France in the 1860s. Its single vector of introduction in Europe was red clover seeds (Trifolium pratense L.), probably coming from Pennsylvania, United States at the time. A. artemisiifolia was later introduced into France in many places and at different times. This species has no natural or effective seed dispersal mechanisms and the spread of this weed in the territory is ensured by human activities that carry the seeds and create disturbed environments favourable to its development. It is now established in the Rhone Valley and a number of different factors (cropping system evolution, climate…
Characterisation of phenotypic plasticity in seedling stage of native and invasive populations in Ambrosia artemisiifolia L.
2012
Increased phenotypic plasticity has often been invoked as an hypothesis to explain the capacity of alien invasive plant species to colonize new environments, because it may enhance the ability of plants to cope with new biotic and abiotic conditions. Following this hypothesis, alien invasive populations should be represented by more plastic genotypes than populations in the native range. In annual species, the seedling stage is of crucial importance for population dynamics but surprisingly very few studies have investigated differences in phenotypic plasticity on seedling traits. Based on populations from the native range (North America) and the invasive range (France) of Ambrosia artemisii…
Gene flow and population admixture as the primary post-invasion processes in common ragweed (Ambrosia artemisiifolia) populations in France
2010
*An improved inference of the evolutionary history of invasive species may be achieved by analyzing the genetic variation and population differentiation of recently established populations and their ancestral (historical) populations. Employing this approach, we investigated the role of gene flow in the post-invasion evolution of common ragweed (Ambrosia artemisiifolia). *Using eight microsatellite loci, we compared genetic diversity and structure among nine pairs of historical and recent populations in France. Historical populations were reconstructed from herbarium specimens dated from the late 19th to early 20th century, whereas recent populations were collected within the last 5 yr. *Re…
How to explain the introduction of common ragweed into Europe during the XIXth century?
2012
EA EcolDur (équipe CAPA) CT3; Various reasons can explain the success of A. artemisiifolia in France and in Europe :* introduction of plants from various sources (in space and time)* strong variability (morphology, size, etc.) * ecological plasticityDifferent situations across areas and countriesThe dominant habitats and the spread vector can differPotentially strong effects of the landscape (soil use)
Can the large ecological amplitude of Ambrosia artemisiifolia explain its invasive success in France?
2008
International audience; In order to understand the successful spread of Ambrosia artemisiifolia in France, the variability of colonised habitat by this species was studied at 48 locations, from its central to peripheral area of distribution. Each site was characterised by a vegetation survey, a description of the A. artemisiifolia population and a soil analysis. Differences in the number of species, Shannon diversity index, evenness index and plant life form spectra were compared among the sites. A total of 276 species occurring along with A. artemisiifolia was observed. Therophytes and hemicryptophytes represented more than 80% of all the species. The two most frequent species occurring al…