Search results for "diversity"
showing 10 items of 3950 documents
Weed diversity mitigates crop yield losses: a perspective from European grain-based systems and insights for biodiversity-based weed management
2020
International audience; Reconciling crop productivity and biodiversity maintenance is one of the main challenges of agriculture worldwide. Weed management is recognized to be a key point for ecological intensification in agriculture because weeds can generate severe yield losses but also represent the base of agricultural trophic networks. Therefore, research in weed science has often opposed two different schools of thought. The drastic decline of biodiversity in agricultural landscapes has either been considered as a sign of efficient weed management or an erosion of the natural capital on which sustainable crop production is founded.Weed: crop competition has historically been studied in…
La biodiversité, un atout pour l’agriculture: rétrospective sur une évolution progressive
2018
National audience; On a vu ces 20 dernières années une montée en puissance de la prise en compte de la biodiversité et de ses rôles en agriculture dans les recherches de l'lnra, avec des changements de paradigmes majeurs en réponse à la nécessité de considérer et de préserver la santé des écosystèmes et des hommes. Les études documentant le déclin de la biod1versité des milieux agricoles ont stimulé le développement d'outils de caractérisation de la biodiversité tandis que l'écologie fonctionnelle a alimenté la compréhension des liens entre biodiversité et fonctionnement des écosystèmes. L'expertise scientifique collective "Agriculture et biodiversité : valoriser les synergies" de 2008 marq…
Diversité génétique et aromatique de la truffe de Bourgogne
2013
Truffles are ectomycorrhizal Ascomycota fungi belonging to the Tuberaceae family and more specifically to the Tuber genus. More than thirty Tuber species are currently described in Europe. In this thesis, we specifically focused on the Tuber aestivum-uncinatum model. This truffle is commonly called "Burgundy Truffle" and has a gastronomic and cultural interest.The first part of this thesis focused on the taxonomic status of the Burgundy truffle (Tuber uncinatum). For this, we used a multi-marker approach combining several genetic markers commonly used at the interspecific scale. Our analyses showed that the two taxa, Tuber aestivum (summer truffle) and Tuber uncinatum are conspecific.In the…
Les effets conjugués de la gestion parcellaire et du contexte paysager et de sa dynamique sur les bioagresseurs et les niveaux de régulation biologiq…
2017
International audience; De nombreux travaux ont mis en évidence que les caractéristiques du paysage environnant les parcelles agricoles influencent les abondances d’ennemis naturels et le niveau de régulation biologiquedans les cultures. Les effets du paysage sur l’abondance de bio-agresseurs sont par contre encore peu étudiés. Les effets du paysage sur la régulation biologique sont parfois contradictoires, souventspécifiques aux sites et de ce fait encore peu généralisables. Des travaux récents suggèrent que ces variations de réponse peuvent résulter d’interactions entre gestion parcellaire et contexte paysager,avec des effets conditionnels du paysage selon le type de gestion parcellaire e…
Quoi de neuf en paléontologie du Paléozoïque ?
2014
7 pages; National audience; En paléontologie,les XIXe et XXe siècles corres-pondentà la mise en place de l’anatomie comparée pour interpréter les fossiles, des corrélations stratigraphiques pour dater les terrains sédimentaires etd e l’usage de la biostratigraphie, de la paléoécologie et de la paléogéographie, plus tardivementde la paléobiologie etd e sacontribution à l’étude des crises de biodiversité, comme composantes des sciences de la Terre. La paléontologie du Paléozoïque n’a pas échappé à cesgrandes tendances. Elle a connu en particulier l’âge d’or dela biostratigraphie paléobotanique et paléopalynologique appliquée à l’exploration età l’exploitation des bassinshouillers du Nord – Pa…
SOIL MICROBIOLOGICAL QUALITY: STATE OF THE ART AND IMPORTANCE OF MICROBIAL COMMUNITIES FOR FRENCH AGRICULTURAL SOILS
2022
Soils are one of the major reservoirs of biological diversity on our planet, hosting a huge diversity of microorganisms. Numerous studies have demonstrated the role of microbial diversity in soil functions, such as nutrient cycling or pathogen management. Given the key role of soil microorganisms in the regulation of soil ecosystem functions, the environmental factors driving soil microbial diversity need to be understood. In France, we have the opportunity to benefit from a national soil survey (called the French Soil Quality Monitoring Network), which represents one of the most extensive and without a priori soil sampling survey available to date. Through several funded projects, we were …
Microbial Community Structure and Density Under Different Tree Species in an Acid Forest Soil (Morvan, France)
2005
Overexploitation of forests to increase wood production has led to the replacement of native forest by large areas of monospecific tree plantations. In the present study, the effects of different monospecific tree cover plantations on density and composition of the indigenous soil microbial community are described. The experimental site of "Breuil-Chenue" in the Morvan (France) was the site of a comparison of a similar mineral soil under Norway spruce (Picea abies), Douglas fir (Pseudotuga menziesii), oak (Quercus sessiflora), and native forest [mixed stand dominated by oak and beech (Fagus sylvatica)]. Sampling was performed during winter (February) at three depths (0-5, 5-10, and 10-15 cm…
PPHD: une plateforme pour le phenotypage a haut debit
2012
International audience; The methodologies for genotyping and high throughput automated platforms for the production of type-omics (genomics, transcriptomics, protected omics ...) have greatly increased over the last few years and are now available to analyze the expression of genes of plants in several environmental conditions. However, a break of conceptual and technical services, non-destructive characterization and dynamic phenotypes, at the organ or plarite, has hundreds of related genotypes (Broadband) remains the limiting factor for the discovery of new characters or new varieties. This systematic exploration of diversity. Genetics within a species or between species requires platform…
Evolution expérimentale
2010
National audience
Mapping field-scale spatial distribution patterns of size and activity of the denitrifier community
2008
International audience