La sensibilité des communautés microbiennes à une augmentation de la température augmente quand la biodégradabilité de la ressource organique baisse

La sensibilité des communautés microbiennes à une augmentation de la température augmente quand la biodégradabilité de la ressource organique baisse. 12. Journées d'Etude des Sols

Apport de composts, fumiers ou lisiers : que deviennent les graines des « mauvaises herbes » ?

Les composts, fumiers ou lisiers contiennent des graines d’adventices ou « mauvaises herbes » qui peuvent représenter un frein à la valorisation de ces matières organiques en agriculture. Des chercheurs de l’Inra ont mis en évidence que l’azote apporté par les fumiers favorise la germination précoce de certaines semences adventices produites après l’apport des matières organiques au sol. Cet azote les empêche ainsi de se développer dans les cultures suivantes, en cas de travail du sol ou de traitements herbicides avant le semis de ces cultures.

Microbial aspects of atrazine biodegradation in relation to history of soil treatment

Among 15 soils with different cropping practices, seven which had an history of repeated atrazine applications showed accelerated degradation of this herbicide. By contrast, grassland or agricultural soils with no recorded atrazine application, at least for the last three years, had a low degradation potential. No direct relation was found between the rate of atrazine mineralisation and the size of the microbial biomass. In adapted soils, the amounts of extractable residues were lowered and the very high percentages of radioactivity from [ring-14C]atrazine recovered as [14C]carbon dioxide demonstrated that N-dealkylation and deamidation were the only processes for micro-organisms to derive …

Epandage de matières organiques exogènes : indicateur de potentialité de stockage de carbone dans les sols et définition de classes de disponibilité d'azote

National audience

Emissions de composés organiques volatils par des sols amendés par des PRO: évolution saisonnière et lien avec la diversité microbienne

National audience

Effet de la monoculture du maïs sur la diversité des populations de Rhizobium

National audience

Apport de matières organiques exogènes en agriculture: indicateur de potentialité de stockage de carbone dans les sols et définition de classes de disponibilité d’azote

CT3; absent

Les communautés microbiennes présentes dans différents types de sols ont une réponse variable à l’apport de produits résiduaires organiques

National audience

Ecological role of mycotoxins in wheat crop residues and consequences on the multitrophic interactions in the soil and further development of Fusarium graminearum

Format du poster : 21 X 29,7; absent

Typology of exogenous organic matters based on chemical and biochemical composition to predict potential nitrogen mineralization

Our aim was to develop a typology predicting potential N availability of exogenous organic matters (EOMs) in soil based on their chemical characteristics. A database of 273 EOMs was constructed including analytical data of biochemical fractionation, organic C and N, and results of N mineralization during incubation of soil–EOM mixtures in controlled conditions. Multiple factor analysis and hierarchical classification were performed to gather EOMs with similar composition and N mineralization behavior. A typology was then defined using composition criteria to predict potential N mineralization. Six classes of EOM potential N mineralization in soil were defined, from high potential N minerali…

Long-term effects of crop management on Rhizobium leguminosarum biovar viciae populations.

Little is known about factors that affect the indigenous populations of rhizobia in soils. We compared the abundance, diversity and genetic structure of Rhizobium leguminosarum biovar viciae populations in soils under different crop managements, i.e., wheat and maize monocultures, crop rotation, and permanent grassland. Rhizobial populations were sampled from nodules of pea- or vetch plants grown in soils collected at three geographically distant sites in France, each site comprising a plot under long-term maize monoculture. Molecular characterization of isolates was performed by PCR-restriction fragment length polymorphism of 16S-23S rDNA intergenic spacer as a neutral marker of the genomi…

Impact d'amendements organiques sur la structure des communautés microbienne des sols : Choix des méthodes, validation et résultats

Effect of repeated organic waste applications on soil microorganisms involved in N cycle and their activities at the plot scale

Dependence of accelerated degradation of atrazine on soil pH in French and Canadian soils

Abstract A series of agricultural soils varying in their atrazine treatment history were sampled from 12 sites in France and two sites in Canada. The soils varied widely with respect to soil chemical, physical and microbiological (total microbial biomass, kinetics of C and N mineralization) properties. Soils treated with as few as two successive atrazine field applications mineralized [U- ring - 14 C]atrazine significantly more rapidly in 35 d laboratory incubations than did soils which had never received atrazine. Longer treatment history tended to favour more rapid mineralization in the so-called “adapted” soils. Up to 80% of the initially applied 14 C-atrazine was mineralized at the end …

Lasting effect of solid waste composts on soil microbial communities

EABIOME; Lasting effect of solid waste composts on soil microbial communities. 16. International Symposium on Microbial Ecology - ISME16

Recherche de bioindicateurs d'impact du recyclage de produits résiduaires organiques en sols cultivés : lien avec la disponibilité de micropolluants organiques et métalliques

Long-term survival of pathogenic and sanitation indicator bacteria in experimental biowaste composts

ABSTRACT For economic, agricultural, and environmental reasons, composting is frequently used for organic waste recycling. One approach to limiting the potential risk from bacterial food-borne illnesses is to ensure that soil amendments and organic fertilizers are disinfected. However, more knowledge concerning the microbiological safety of composted substrates other than sludge and manure is necessary. Experimental in-vessel biowaste composts were used to study the survival of seeded Listeria monocytogenes , Salmonella enterica subsp. enterica serotype Enteritidis, and Escherichia coli . Four organic waste mixtures, containing various proportions of paper and cardboard, fruits and vegetabl…

Évaluation de bioindicateurs d'impact du recyclage de produits résiduaires organiques en sols cultivés: lien avec les modifications des caractéristiques physico-chimiques du sol

Communication orale, résumé étendu; absent