Search results for "pcr"
showing 10 items of 438 documents
Species-specific prey choice of carabid beetles in European cereal fields
2017
National audience; Trophic interactions between species in agroecosystems provide key regulation ecosystem services and therefore also determine the dynamics, robustness and resilience of service provision. To achieve international goals of reducing application of pesticides without compromising key provisioning ecosystem services such as crop yield, recent research attaches importance to the biological control potential of carabid beetles. However, apart from feeding on pest species and weed seeds, carabids also consume non-pest prey (alternative prey) such as collembolans and earthworms, which can play a contradictory role in the efficacy of pest and weed control. Most carabids are descri…
Qualité du Sol - Méthode pour extraire directement l'ADN d'échantillons de sol (Norme française - internationale)
2012
La présente Norme internationale spécifie une méthode pour extraire directement l'ADN d'échantillons de sol en vue d'analyser la structure globale et l'abondance des communautés microbiennes du sol en utilisant des techniques de PCR. Cette méthode est principalement destinée aux sols agricoles et forestiers. Cette méthode peut ne pas être appropriée aux sols riches en matières organiques (par exemple sols de tourbières) ou aux sols très pollués par des polluants organiques ou des métaux lourds. L'extraction directe de l'ADN d'échantillons de sol fournit des informations précieuses sur l'abondance et la structure des communautés microbiennes qui sont des paramètres clés pour estimer la biodi…
Use of fonctional genes to quantify denitrifiers in the environment
2006
; During the last decade, application of molecular methods using cultivation-independent approaches has provided new insights into the composition and structure of denitrifying communities in various environments. However, little is known about their abundance, and quantification is still performed using cultivation-based approaches, which are not only biased by the inability to cultivate of many micro-organisms but also fastidious and time-consuming. Two types of cultivation-independent approaches have recently been developed to quantify denitrifiers. The first type, which is based on the hybridization technique, comprises the use of Southern hybridization and DNA arrays. The second type,…
Etude de la stabilité de l'ADN suivant différentes modalités de conservation
2014
Rapport de stage BTS EA (Plateforme et VN) GenoSol; DEUG
Responses of soil bacterial and fungal communities to extreme soil drought and rewetting
2013
Question: The patterns of resource allocation and activity of the soil microbial community over the dry summer in Mediterranean grasslands are still largely unknown. The microbial response to summer desiccation reflects adaptation strategies, setting the stage for a large rainfall-induced soil CO2 pulse upon rewetting, an important component of the ecosystem carbon budget. Methods: In three California annual grasslands, the present (DNA-based) and potentially active (RNA-based) soil bacterial and fungal communities were tracked over a summer season and in response to controlled rewetting of intact soil cores. Phylogenetic marker genes for bacterial (16S) and fungal (28S) RNA and DNA were se…
Distribution de bactéries pathogènes dans les sols évaluée par PCR quantitative en temps réel
2009
National audience
Caractérisation moléculaire des populations microbiennes des sols de la réserve de Sancy par extraction d'ADN et PCR quantitative
2014
Rapport de stage de 2ème année de BTS EA (Plateforme) SPE (Mélanie) GenoSol
Améliorer la méthodologie standard de la qPCR pour l’analyse de la densité microbienne dans la plateforme GenoSol. Mémoire de stage BTS de 2ème année…
2019
Le stage a été dédié à la comparaison de la méthode de ddPCR à celle de la PCR quantitative pour évaluer le nombre de copies de gènes 16S dans un échantillon d’ADN extrait de sol.
Studies of root colonization by a microcosm community of arbuscular mycorrhizal fungi unsing nested PCR
1998
International audience
The Largest Subunit of RNA Polymerase II as a New Marker Gene to Study Assemblages of Arbuscular Mycorrhizal Fungi in the Field
2014
Due to the potential of arbuscular mycorrhizal fungi (AMF, Glomeromycota) to improve plant growth and soil quality, the influence of agricultural practice on their diversity continues to be an important research question. Up to now studies of community diversity in AMF have exclusively been based on nuclear ribosomal gene regions, which in AMF show high intra-organism polymorphism, seriously complicating interpretation of these data. We designed specific PCR primers for 454 sequencing of a region of the largest subunit of RNA polymerase II gene, and established a new reference dataset comprising all major AMF lineages. This gene is known to be monomorphic within fungal isolates but shows an…