Search results for "soil"
showing 10 items of 3493 documents
Biogeographical patterns of soil bacterial communities.
2009
International audience; This study provides the first maps of variations in bacterial community structure on a broad scale based on genotyping of DNA extracts from 593 soils from four different regions of France (North, Brittany, South-East and Landes). Soils were obtained from the soil library of RMQS (Réseau de Mesures de la Qualité des Sols = French soil quality monitoring network). The relevance of a biogeographic approach for studying bacterial communities was demonstrated by the great variability in community structure and specific geographical patterns within and between the four regions. The data indicated that the distribution of bacterial community composition might be more relate…
Fixation symbiotique et effet précédent : toutes les légumineuses ne se valent pas
2018
National audience; [pas de résumé]
Historique de l'utilisation des herbicides en France: premières analyses
2010
A data base on the herbicides used in France since 1961 has been built up from the phytosanitary index annually edited by the Association de Coordination Technique Agricole (ACTA). This data base gives the number of active ingredients, associations and commercial products registered every year and for each crop. We also gathered the modes of action, the way of absorption sites and the species susceptibility. Since 1961, 215 molecules have been registered. The number increased regularly with a maximum of 138 in 2002 and only around 100 remain in 2010. The evolution of the number of modes of action available for weed control in wheat is discussed.
Symbiose fixatrice de l'azote des légumineuses : principes de fonctionnement, impacts agronomiques et environnementaux
2017
National audience
Weed seeds ability to emerge on the soil surface
2015
International audience; Annual weeds have to produce seeds each year to maintain their populations. These seeds fallon the soil surface. Seeds exposed to light during their moistening (i.e. caused by rain) bettergerminate than seeds in the darkness (i.e. buried). However, rare studies quantified the unique andcombined effects of light, moisture and burial depth on the germination process. We investigated,in a greenhouse experiment in 2014, the impact of seed moisture (Moistened vs. Dried), lightduring moistening (Darkness vs. Light) and burial depth (Buried vs. Surface) on germination of 12annual weed species contrasted on their seed traits and germination periods (Alopecurusmyosuroides Hud…
Etude de l’infection la plante parasite Rhamphicarpa fistulosa en riziculture au Togo
2013
Rhamphicarpa fistulosa (Hochst.) Benth. is an annual facultative root-parasitic weed found in lowlands and floodplains in tropical Africa. It has been reported as the major constraint to rice cultivation in the savannah region of Togo. A survey was conducted in 2012 to access its distribution and to collect information on farmers' knowledge of its control. Rhamphicarpa fistulosa was found in 80% of the 33 visited lowlands. The period of abundance is in August-September when the highest infection (90%) was found on sandy and clay soils. When the parasite was present, 94 other weeds belonging to 24 botanical families were recorded. As management method, farmers use weeding and chemical fertil…
Infestation de Rhamphicarpa fistulosa (Hoschst.) Benth. en riziculture de bas-fonds au nord du Togo
2016
International audience; Le riz constitue de nos jours la base alimentaire de plus de 2,5 milliards de personnes en Afrique subsaharienne où sa demande ne cesse de croître. Pour faire face à cette demande qui dépasse souvent doublement les productions nationales, et pour diminuer ses importations sans cesse croissantes, le Togo à l’instar des pays ouest-Africains a élaboré un document stratégique qui mise sur l’extension et la productivité des rizières de bas-fond. Malheureusement, les bas-fonds rizicoles en Afrique tropicale sont souvent confrontés à la pression des adventices et plus particulièrement des adventices parasites de la famille des Orobanchaceae. Rhamphicarpa fistulosa, plante h…
Impacts of Integrated Weed management in cropping systems on N2O emissions from soils
2014
International audience
Caractérisation du transfert d’eau et des pertes en herbicides dans des sols soumis à différents systèmes de culture économes en herbicides
2012
International audience
Drought affects weed emergence in cover crops of no-till systems
2014
Session 7 - Crop science in changing environmentsEAEcolDur; International audience