Search results for "VECTEUR"
showing 10 items of 13 documents
Impact of vector dispersal and host-plant fidelity on the dissemination of an emerging plant pathogen
2012
International audience; Dissemination of vector-transmitted pathogens depend on the survival and dispersal of the vector and the vector's ability to transmit the pathogen, while the host range of vector and pathogen determine the breath of transmission possibilities. In this study, we address how the interaction between dispersal and plant fidelities of a pathogen (stolbur phytoplasma tuf-a) and its vector (Hyalesthes obsoletus: Cixiidae) affect the emergence of the pathogen. Using genetic markers, we analysed the geographic origin and range expansion of both organisms in Western Europe and, specifically, whether the pathogen's dissemination in the northern range is caused by resident vecto…
Identification and biological traits of a planthopper from the genus Pentastiridius (Hemiptera: Cixiidae) adapted to an annual cropping rotation
2009
International audience; Cixiid planthoppers have been shown to vector phloem-limited prokaryotes associated with plant diseases world-wide. In eastern France, an emerging disease of sugar beet called syndrome basses richesses has been associated with phloem-restricted bacteria transmitted by a cixiid planthopper within the genus Pentastiridius. Early investigation suggested the species being Pentastiridius beieri. On the basis of a morphological and phylogenetic study we report the identification of the planthopper as Pentastiridius leporinus. Furthermore we report some biological traits of the species, which shows a surprising ecological adaptation to an annual cropping rotation sugar beet…
American Trypanosomiasis Chagas disease : one hundred years of research
2017
Abstract In understanding biodiversity, taxonomy and systematics work together, although the two terms are often confused. The objective of systematics is to understand the natural mechanisms responsible for the biodiversity, while the task of taxonomy is to set up a useful classification of the organisms concerned. The Triatominae (Hemiptera, Reduviidae) are the vectors of Chagas disease. Their classification faces frequent divergence between the modern concepts of systematics and the traditional, morphologically-based, classification. This chapter revises the main concepts of species in general, and their application to the Triatominae. We summarize the current classification of the vecto…
From resurgent functions to real resummation through combinatorial Hopf algebras
2014
Pas de résumé en anglais.
Nuclear rDNA-based molecular clock of the evolution of Triatominae (Hemiptera : Reduviidae), vectors of Chagas disease
2000
The evolutionary history and times of divergence of triatomine bug lineages are estimated from molecular clocks inferred from nucleotide sequences of the small subunit SSU (18S) and the second internal transcribed spacer (ITS-2) of the nuclear ribosomal DNA of these reduviids. The 18S rDNA molecular clock rate in Triatominae, and Prosorrhynchan Hemiptera in general, appears to be of 1.8% per 100 million years (my). The ITS-2 molecular clock rate in Triatominae is estimated to be around 0.4-1% per 1 my, indicating that ITS-2 evolves 23-55 times faster than 18S rDNA. Inferred chronological data about the evolution of Triatominae fit well with current hypotheses on their evolutionary histories…
Une relation trophique originale : la vection entomophile d'agents pathogènes
2013
Bgpi : équipe 6 chapitre 34; Une relation trophique originale : la vection entomophile d'agents pathogènes
Study of biogenic amines metabolism in wine lactic acid bacteria
2011
Biogenic amines are indesirable compounds found in fermented products like wine. Lactic acid bacteria from wine, including Oenococcus oeni, the main actor of malolactic fermentation, are able to produce these molecules from nitrogenous precursors. In order to limited biogenic amines accumulation, it is necessary to understand the role of this production by strains responsible for the synthesis of these metabolites in food. That is why the European BiamFood project was put in place. Along my thesis, molecular tools were developed in order to mutate O. oeni genes (encoding decarboxylases), and to express genes of interest. Genetic clusters hdc from L. higardii and odc from O. oeni, responsibl…
Connaissances nécessaires à la gestion du risque "écorces sensibles au nématode du pin"
2018
Connaissances nécessaires à la gestion du risque "écorces sensibles au nématode du pin"
Le manuel de droit commercial : vecteur d'autonomie (XIXe-milieu Xxe siècle)
2014
International audience
Une envahissante dans le paysage : cas de l’ambroisie à feuilles d’armoise
2014
L’ambroisie à feuilles d’armoise (Ambrosia artemisiifolia L.) est une espèce annuelle envahissante introduite en France à la fin du XIXe siècle. Plante rudérale, tolérante à de nombreux stress, l’ambroisie se développe essentiellement dans les habitats perturbés. Les principaux milieux occupés sont les parcelles agricoles, les bords de route et les zones perturbées par les activités anthropiques (jachères industrielles, zone de dépôt de matériaux …). Les berges de rivière constituent le seul habitat naturel dans lequel l’ambroisie peut former d’importantes populations. La semence d’ambroisie n’a pas de structure particulière favorisant son invasion. Trop lourde pour être dispersée par le ve…