Search results for "Vegetal Biology"
showing 10 items of 1601 documents
Infestation chez le pigeon biset (Columbia livia) en environnement urbain par différentes souches bactériennes pathogènes : prévalence dans la popula…
2014
Rapport de Stage de Master 2 EA MERS CT3; Master; La dissémination des zoonoses est une préoccupation majeure pour les autorités concernées en termes de santé publique. Ces maladies font l’objet de suivi temporel et spatial afin de comprendre les facteurs favorisant leur dissémination. Les oiseaux, de par leur forte capacité de mouvement représentent un groupe taxonomique très étudié dans la dissémination des pathogènes. Le pigeon biset (Columbia liva) est une des espèces les plus présentes dans l’environnement urbain et peut-être porteur de différentes souches bactériennes pathogènes. Cette étude s’est intéressé à estimer l’état sanitaire des pigeons au sein de la ville de Dijon. La recher…
Trait distribution within winter wheat fields can partly be explained by disturbances and competition for resources
2013
International audience; Weed species are not homogeneously distributed into field elements (Cordeau et al. 2012)*.In a field, weed species are mainly competing with the crop and constrained by management practice (i.e.disturbances). In the crop edge, less unfavorable conditions for weed development (i.e.absence of direct crop competition,l ess frequent disturbances could explain the greater diversity of weeds.To understand this observation, a functional approach base dont raits known to respond both to disturbances and to competitive or facilitative interactions can be used.Our assumptions are that(i)the crop edge is likely to all owawi derrange of ecological strategies thus promoting speci…
Mutant ACCase alleles endowing herbicide resistance have a direct effect on seed germination
2013
Germination and emergence dynamics and herbicide resistance are adaptive traits crucial for weed persistence in arable fields. Herbicide resistance alleles can have pleiotropic effects on other traits. We investigated the pleiotropic effects of acetyl-coenzyme A carboxylase (ACCase) alleles L1781, N2041 or G2078 on seed germination and seedling emergence in the grass weed Alopecurus myosuroides (black-grass). We used black-grass populations with homogenised genetic backgrounds that segregated for L1781, N2041 or G2078 ACCase alleles. In two series of experiments, germination dynamics and seedling growth were compared among seeds containing embryos carrying no, one or two copies of a given m…
An endophytic bacillus subtilis strain protects grapevine against downy mildew by direct effect and defense stimulation
2018
National audience; Plasmopara viticola, the causal agent of grapevine downy mildew, is one of the most devastating grape pathogen. Phytochemicals are generally used to control infections, but the appearance of resistant strains and the concern for possible adverse effects on environment and human health are increasing the search for alternative strategies. Biological control has received a great deal of attention as an alternative and promising measure to control different plant diseases. Many antagonistic microorganisms, including Bacillus spp., have been exploited against different pathogens. Bacillus spp. activity results from multiple modes of action including antibiosis, competition, a…
Loss in microbial diversity affects nitrogen cycling in soil
2013
International audience; Microbial communities have a central role in ecosystem processes by driving the Earth's biogeochemical cycles. However, the importance of microbial diversity for ecosystem functioning is still debated. Here, we experimentally manipulated the soil microbial community using a dilution approach to analyze the functional consequences of diversity loss. A trait-centered approach was embraced using the denitrifiers as model guild due to their role in nitrogen cycling, a major ecosystem service. How various diversity metrics related to richness, eveness and phylogenetic diversity of the soil denitrifier community were affected by the removal experiment was assessed by 454 s…
Bridging microbial community ecology and nitrogen cycling in soil
2011
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Les herbicides β-tricétones : devenir et impact écotoxicologique dans les sols agricoles et caractérisation de souches bactériennes dégradantes
2016
P-triketone herbicides : fate and ecotoxicological impact in arable soils and characterization of degrading bacterial strains abstract :This work aims to describe the ecodynamics of synthetic (sulcotrione and mesotrione) and natural (leptospermone) -triketone herbicides and to estimate their ecotoxicological impact on the bacterial community in arable soils. The processes involved in the dissipation of these herbicides (adsorption and biodegradation) have been studied in soil microcosms. Two bacterial strains, Bradyrhizobium sp. SRl able to degrade sulcotrione and mesotrione, and Methylophilus sp. LS1 degrading leptospermone, have been isolated. A bank of 12 ooo mutants of Bradyrhizobium sp…
Volatile organic compounds: a role in elicitor-induced resistance of grapevine against pathogens?
2014
International audience; As Vitis vinifera varieties are susceptible to fungal diseases, numerous chemical treatments are generally required to ensure the quantity and quality of the harvest. However, in the context of sustainable viticulture, there are increasing societal request, political incitation, and winegrowers’ awareness to reduce the use of pesticides. Among possible solutions the use of elicitors that could be included in integrated pest management or biocontrol strategies might be very promising. These bioactive compounds are able to trigger plant defences, leading to induced resistance (IR) against pathogens. Despite IR can be elicited very successfully in controlled environment…
Identification of the VvFLS2 grapevine flagellin receptor by a functional genomics strategy
2012
La collection de semences adventices de l’UMR Agroécologie (Dijon)
2019
National audience; Les semences adventices peuvent survivre dans le sol durant de nombreuses années. Le stock semencier constitue ainsi un point fondamental du développement des communautés adventices, en lien avec leur stratégie de survie. Son étude apparaît donc comme un point crucial dans la compréhension de la dynamique des adventices. Au sein de l’UMR Agroécologie, des travaux sont menés pour étudier différents processus biologiques liés au cycle de vie des adventices, les phénomènes de résistance des adventices aux herbicides ainsi que les interactions entre les adventices et d’autres organismes (prédation des graines par des insectes par exemple). Pour soutenir ces activités de reche…