Search results for "MICROORGANISME"
showing 10 items of 107 documents
La lutte biologique. Vers de nouveaux équilibres écologiques
2010
Pisum sativum – Pseudomonas interactions : influence on iron nutrution, growth and immunity of the host plant
2020
The project aimed at making progress in the knowledge of the iron-mediated interactions between pea and fluorescent pseudomonads in order to promote the iron-nutrition and health of the host-plant. A bibliographical study was conducted to draw up the state of the art concerning the influence of rhizosphere microorganisms on plant iron status (Chapter 1).Pisum sativum has been chosen as an agronomic model-plant because of its high potential in agroecology and in Human nutrition related to its ability to fix atmospheric nitrogen and to the high amino-acids content of its seeds. However, this species suffers from a high susceptibility to iron deficiency as expressed by the well-known chlorosis…
The dynamics of soil bacterial community structure in response to yearly repeated agricultural copper treatments
2008
International audience; The annual dynamics of soil bacterial community structure, including early, dose-dependent and transient modifications, was observed consecutively at different levels of copper contamination (high: 48 kg Cu ha−1, low: 16 kg Cu ha−1) repeated yearly over a three-year field experiment. Repeated low-level Cu contamination led to an increase in community stability to metal stress without a long-term shift in the population structure, whereas repeated high-level Cu contamination induced a novel and stable bacterial community structure. Furthermore, field experimentation highlighted that episodic climatic stress can modulate copper impact by enhancing community stability.
Protein and DNA fingerprinting of a soil bacterial community inoculated into three different sterile soils
2007
The functional and genetic structures of a soil bacterial community were characterized after inoculation into three different sterile soils using a protein and DNA fingerprinting method, respectively. Principal component analysis (PCA) of profiles revealed that, depending on soil characteristics, bacterial communities with similar genetic structures harbored different functional structures and thus could potentially be of differing ecological significance for soil functioning. Co-inertia analysis between protein fingerprinting data and the corresponding sets of soil physicochemical characteristics demonstrated the correlation between the functional structure of the bacterial community and s…
Influence of type III bacterial secretion system on the interactions between plant and non pathogenic fluorescent Pseudomonads spp.
2010
No abstract
Origins of the blemishes of potato tubers : from the soil microbiology to the pedoclimatic environment
2010
The visual quality of fresh potatoes, Solanum tuberosum, became a dominant criterion and a significative economical issue in potato market. According the vegetative reproduction of this species, requirements for visual quality are also needed for potato seed tubers. As an organ for reserve and propagation, the tuber grows underground and is in contact with soil-borne microorganisms, making it potentially exposed to blemishes, for the majority of which the origin is still unclear. The objective of this work is to make an inventory of those tuber blemishes, to characterize them and determine their causes. After the establishment of consensual nomenclature and classification of the blemishes, …
Impact of distribution heterogeneity of microorganisms and 2,4-D on biodegradation processes in soil : experiment and modelling
2013
Impact of distribution heterogeneity of microorganisms and 2,4-D on biodegradation processes in soil : experiment and modelling. Conference on Pesticide Behaviour in Soils, Water and Air (York 2013)
Copper Dynamics and Impact on Microbial Communities in Soils of Variable Organic Status
2008
International audience; The effect of soil organic status on copper impact was investigated by means of a microcosm study carried out on a vineyard soil that had been amended with varying types of organic matter during a previous long-term field experiment. Soil microcosms were contaminated at 250 mg Cu kg−1 and incubated for 35 days. Copper distribution and dynamics were assessed in the solid matrix by a sequential extraction procedure and in the soil solution by measuring total and free exchangeable copper concentrations. Copper bioavailability was also measured with a whole-cell biosensor. Modifications of microbial communities were assessed by means of biomass-C measurements and charact…
Influence of type III bacterial secretion system on the interactions between plant and non pathogenic fluorescent Pseudomonads spp.
2010
No abstract
THE FRENCH NATIONAL SOIL QUALITY MONITORING NETWORK (RMQS) AS A SUPPORT FOR MONITORING SOIL BIODIVERSITY: past, present and future programs
2021
Soil biodiversity would represent about 25% of the species on Earth. It is threatened, and although it is essential for human activities, it remains largely unknown. The French National Soil Quality Monitoring Network (RMQS) has a significant impact in removing the grey areas through its programs on soil microorganisms, soil meso and macrofauna, meadow flora, truffles and more recently enzymatic activities. The first distribution maps of bacterial phyla on a national scale and of soil fauna on a regional scale (in Brittany) have been developed. For the white truffle, three new areas of presence have been identified in France. The habitats of the bacteria were also described for the first ti…