Search results for "Bios"
showing 10 items of 2557 documents
Rhizobium leguminosarum biovar viciae genotypes interact with pea plants in developmental responses of nodules roots and shoots
2007
International audience; The variability of the developmental responses of two contrasting cultivars of pea (Pisum sativum) was studied in relation to the genetic diversity of their nitrogen-fixing symbiont Rhizobium leguminosarum bv. viciae. A sample of 42 strains of pea rhizobia was chosen to represent 17 genotypes predominating in indigenous rhizobial populations, the genotypes being defined by the combination of haplotypes characterized with rDNA intergenic spacer and nodD gene regions as markers. We found contrasting effects of the bacterial genotype, especially the nod gene type, on the development of nodules, roots and shoots. A bacterial nod gene type was identified that induced very…
Pois protéagineux : cheminement de la recherche génétique pour la sélection des paramètres à prendre en compte pour l’amélioration de la stabilité du…
2013
Field Pea: development of genetic research for the selection of parameters to take into account to improve yield stability. Legumes were essential in rotations in the past, but they fell off during the 20th century. Maybe they will come back into favour in the 21st century thanks to its economy, agri-environment and food assets. Field Pea is the main crop of this family in France, but it remains underdeveloped because its unstable yield does not enable the farmers to ensure their income security. Therefore researchers should focus on yield stability. Modelling Pea remains difficult because of its indeterminate development. Parameters to take into account are many and their significance must…
Prevalence of Mycobacterium bovis in agroecosystems : analysis of potential environmental reservoirs (soil, fresh water, soil fauna and aquatic fauna…
2016
Bovine tuberculosis is an infectious disease caused by Mycobacterium bovis. This disease affects cattle, and many species of domestic and wild mammals, and humans. The circulation of the bacteria in various multi-host systems promotes the maintenance of the disease and the contamination of cattle in the vicinity. Beside direct transmission of the bacteria through the respiratory route, indirect transmission, through inhalation or ingestion of environmental matrices contaminated by an infected animal excretory, is suspected in several countries. Environmental contamination with M. bovis appears to be a crucial factor in the persistence of the infection in multi-host systems. In Côte d'Or, a …
Services écosystémiques rendus par la symbiose mycorhizienne à arbuscule au vignoble
2021
National audience; Qu’appelle-t-on symbiose mycorhizienne ?Le sol est un milieu vivant puisque dans quelques grammes de terre fine se trouvent environ 200 milliards de bactéries, 100 km de filaments de champignons et 200 000 insectes, vers et protozoaires (figure 1). Cette vie souterraine va partager son habitat (le sol) avec les ceps de vigne. Ce fameux « vivre ensemble » est alors défini par le terme « symbiose » (du grec syn : ensemble ; et bios : vivre). Cette définition ne fait pas de distinction vis-à-vis des modalités d’interaction qui peuvent s’établir entre les deux organismes impliqués. Ainsi, des interactions neutres, ou encore du véritable parasitisme, pour lequel un partenaire …
Comparaison de l’efficience de cinq souches de Rhizobium sur 18 génotypes de pois
2014
Legume-rhizobium association leads to the production of nodules on plant roots, in which atmospheric nitrogen is caught by the bacteria and exchanged for plant carbohydrates. This symbiotic association is probably the best way to increase nitrogen fertilization without using biological or chemical input. Symbiosis mechanisms between both species are thus a challenge for the current research. Previous studies have shown that rhizobia are not equally selected by the different pea genotypes. The objective of this study was to assess if peas select the most efficient bacterial strain. In order to answer this question, we sowed 18 pea genotypes and inoculated each of them with five different rhi…
Early Jurassic normal faulting in a carbonate extensional basin: characterization of tectonically driven platform drowning (High Atlas rift, Morocco).
2009
18 pages; International audience; This paper describes a tectonostratigraphic model of the synrift evolution of the Early Jurassic High Atlas rift of Morocco. The model is constrained by mapping of a set of inverted extensional blocks, by facies analysis of carbonate platform and turbiditic to hemipelagic synrift deposits, and by high-resolution (n 3 100 ka) biostratigraphy of the Early Jurassic succession. The chronostratigraphic packages of the High Atlas of Rich vary significantly in thickness, facies and architecture from one tectonic block to another. Our study shows how synrift strain varied in space and time over a long time interval (14 Ma) around the High Atlas rift. Initially, in …
Sédimentologie et quantification de la subsidence des séries liasiques dans le Haut Atlas Central marocain (coupe de Foum Zabel, région de Rich).
2007
13 pages; International audience
Calculating the long-term displacement rates of a normal fault from the high-resolution stratigraphic record (early Tethyan rifting, French Alps)
2003
Displacement rates of normal faults deduced from stratigraphic data are often unreliable. Here we calculate the velocity of motion on a normal fault from the variations in accommodation potential on both sides of the fault within a highresolution time-frame established by biostratigraphy and physical stratigraphy. Our example is the Ornon normal fault bounding the Early Jurassic Bourg-d’Oisans Basin formed during Tethyan rifting. We show that motion on the fault was discontinuous when examined at high resolution and over a long time interval. During a first interval (Hettangian to Sinemurian Arietites bucklandi zone) a low rate of displacement (= 202–423 m Myr -1 ) coeval with diffused exte…
Analysis of headspace of flavour compounds using PTR-ToF Mass Spectrometry: optimisation of acquisition parameters
2011
National audience
Concept of dynamic DNA network dedicated to DNA-Protein interactions studies
2007
The approach lies on the development of an original DNA biosensor. This self-assembled DNA biochip is constituted of a tethered lipid membrane presenting « protein/DNA » complexes. This unique assembly, using a highly flexible bifunctional molecular spacer and a fluidic matrix, allows the control of oligonucleotides surface density and their mobility thus favouring hybridization of the DNA probes in liquid environment and under weak constraints. Recent Surface Plasmon Resonance experiments lead to building of protein/DNA dimers presenting two special DNA sequences recognized by regulation proteins. We demonstrated the capacity and relevance of this biosensor in the case of an estrogen recep…