Search results for "component"
showing 10 items of 1682 documents
Transcriptional response of Medicago truncatula sulphate transporters to arbuscular mycorrhizal symbiosis with and without sulphur stress
2013
Sulphur is an essential macronutrient for plant growth, development and response to various abiotic and biotic stresses due to its key role in the biosynthesis of many S-containing compounds. Sulphate represents a very small portion of soil S pull and it is the only form that plant roots can uptake and mobilize through H(+)-dependent co-transport processes implying sulphate transporters. Unlike the other organically bound forms of S, sulphate is normally leached from soils due to its solubility in water, thus reducing its availability to plants. Although our knowledge of plant sulphate transporters has been growing significantly in the past decades, little is still known about the effect of…
Et si une impasse de désherbage en agriculture de conservation des sols vous poussait à retravailler le sol ? Quelle intervention choisiriez-vous ?
2019
National audience; En Agriculture de Conservation des Sols (ACS), la perturbation minimale du sol est l’un des trois prin-cipes. Si l’impasse se fait sentir mieux vaut repenser le système que de laisser le mur se rapprocher à grands pas. Trois types de gestion d’interculture (Labour, travail superficiel (TCS) et semis direct avec glyphosate (SD)) ont été comparés sur des parcelles conduites sans labour depuis 17 ans dont les 7 dernières années en ACS sur le domaine de l’INRA de Dijon avant implantation d’un blé, sur un dispo-sitif en bandes répétées sur quatre parcelles. Des relevés de flore adventice, rendement et compo-sante de rendement ont été faite. Les densités moyennes sont faibles p…
Guinean and sahelian rainfall anomaly indices at annual and monthly scales (1933-1990)
1994
The annual and monthly rainfall variability in north tropical Africa are analysed by principal component analysis in order to detect the main coherent modes. The Sahel constitutes the first mode, although it is divided close to 1O"W into an Atlantic section and a Continental section. The Guinean zone is less coherent, and is divided into distinct modes. The subequatorial area never formed a distinct mode. Rainfall variability for the coherent areas is constructed from rainfall anomaly indices (RAI), based on the coherent areas, and a rainfall typology taking into account the spatial pattern of the rainfall anomaly fields and the intensity of the anomaly. Their evolution (mainly since 1950) …
Understanding the odor mixture
2013
International audience
Terahertz Biomedical Imaging: From Multivariate Analysis and Detection to Material Parameter Extraction
2017
Terahertz imaging is an interesting route for biomedical analysis. In particular, cancer imaging is a subject of study for different teams [1,2]. A work is done in Bordeaux in partnership with a hospital to do terahertz analysis of breast tissue. This work is done in reflection with time domain imaging setup with fresh samples. The aim is to accurately assess tumor margins and which could in the future allow a quick validation of the precision of the surgical procedure and know if new surgery should be performed. We have presented in a previous paper [3] the use of automatic methods of image generation with different parameters [4] in order to explore the different contrasts that exist in t…
Microbial diversity and structure are drivers of the biological barrier effect against Listeria monocytogenes in soil
2013
International audience; Understanding the ecology of pathogenic organisms is important in order to monitor their transmission in the environment and the related health hazards. We investigated the relationship between soil microbial diversity and the barrier effect against Listeria monocytogenes invasion. By using a dilution-to-extinction approach, we analysed the consequence of eroding microbial diversity on L. monocytogenes population dynamics under standardised conditions of abiotic parameters and microbial abundance in soil microcosms. We demonstrated that highly diverse soil microbial communities act as a biological barrier against L. monocytogenes invasion and that phylogenetic compos…
Identification of the Trail-Following Pheromone of the Pest Termite Amitermes evuncifer (Isoptera : Termitidae)
2010
International audience; Amitermes evuncifer (Termitidae, Termitinae) is a pest termite in several countries of Africa, damaging crops and buildings. The trail-following pheromone of this termite was isolated from worker sternal glands and identified by GC-MS after solid phase microextraction (SPME). The pheromone is composed of (3Z,67,8E)-dodeca-3,6,8-trien-1-ol (dodecatrienol) and neocembrene acting in synergy, neocembrene being 5-10 times more abundant than dodecatrienol. Dodecatrienol alone is able to elicit trail-following in workers, whereas neocembrene alone is inactive. However, the association of both components induces a significantly higher trail-following activity. Multicomponent…
Strategic tillage in Conservation Agriculture : consequences on weed communities and winter wheat productivity
2021
In Europe, Conservation Agriculture is currently challenged by higher weed pressure, potential glyphosate ban andreduced crop yield. The introduction of strategic tillage could be a viable option to diversify selection pressures onweeds and increase crop yield. Three types of fallow management (ploughing (CT), reduced tillage (RT), no-till withglyphosate (NT)) were compared on four fields after 17 years of no-plough, which ended with 7 years of NT. Weeddensity, weed composition, crop productivity and yield components were assessed in the following winter wheat.The reintegration of tillage after 17 years of Conservation Agriculture proved to be a major driver of weed communities before weedi…
Carbon storage in soils by ancient and modern wheat varieties
2022
Les émissions anthropiques de gaz à effet de serre sont le principal moteur du changement climatique. Le plan Climat, issu de la COP 21 tenue à Paris en 2015, vise à atteindre la neutralité carbone à l'horizon 2050. Pour atteindre cette neutralité carbone, les gaz à effet de serre doivent d'abord être stabilisés, puis fortement réduits au cours du siècle prochain. Dans cette dynamique, l'initiative « 4 pour 1000 » fixe comme objectif d'atteindre un taux de croissance annuel du stock de carbone dans les sols de 0,4% par an. Ce stockage additionnel devrait compenser les émissions de CO2 dans l'atmosphère liée aux activités humaines. Les sols agricoles sont identifiés comme un compartiment de …
Sensory analysis of Burgundy Pinot noir wines: A comparison of orthonasal and retronasal profiling
1999
Thirty Burgundy Pinot noir wines were evaluated by quantitative descriptive profile by nose (BN) and by mouth (BM) separately, by a trained panel composed of 12 judges. A specific vocabulary of 20 terms was developed. Sensory results were analyzed and compared by univariate and multivariate statistical techniques. Principal component analyses of the mean ratings BN and BM were fairly comparable regarding correlation among variables and the position of the wines. However, five sensory characteristics seem to be more intensely perceived BM, against 6 BN. Panel discrimination of the wines and panel repeatability in the measure were found to be slightly better BN than BM. A further canonical di…