Search results for "Interactions"
showing 10 items of 1963 documents
A study on texture-taste-aroma interactions: physico-chemical and cognitive mechanisms
2009
International audience; Texture–taste, texture–aroma and aroma–taste interactions were examined in custard desserts varying in viscosity (at identical composition), sucrose level and aroma nature. All reciprocal interactions were investigated, with each binary interaction addressed through an independent sensory study. Rheological, in vivo aroma release and sucrose release measurements were run in parallel to control for a possible physico-chemical origin of these interactions. Observed interactions were found to be dependent upon the nature of the sensory modalities involved; physico-chemical mechanisms could only in some instances entirely explain these interactions. Taste and aroma did n…
Réponse des interactions plante-sol aux régimes de précipitations
2018
Water availability governs terrestrial nutrient cycles by impacting the functioning of both plants and of soil microorganisms. The predicted changes in precipitation patterns (i.e. the magnitude and frequency of precipitation events) associated with climate change, will thus likely have important consequences on ecosystem functioning. Dry and seasonally dry ecosystems are particularly vulnerable to changes in precipitation patterns, as they are already constrained to a large extent by water availability. However, more mesic systems may also experience dry periods that may impact plant-soil functions. In this thesis, experiments in soil-only systems and plant-soil systems were used to gain i…
Effects of precipitation regime on soil bacterial and fungal activity upon rewetting of a plant-soil system using 18O-SIP: depth matters
2017
EASPEBIOmEDOCT INRA; Climate change is predicted to affect not only the amount but also the temporal distribution of rain. Changes in frequency and amplitude of rain events, likely shape the activity of plants and soil microbes. Fluctuating water conditions will differ with soil depth between precipitation patterns, affecting plant growth and may result in differential microbial response upon rewetting. Our objective was to investigate, in plant-soil systems, the response of the metabolically active microbial communities to a rewetting event and to which extent this was modulated by 1) soil depth and 2) precipitation legacy. Wheat planted in soil mesocosms were subjected to frequent or infr…
Genes encoding transcription factors in Glomus intraradices and their expression at the appressoria stage of arbuscular mycorrhiza interactions
2007
International audience; Molecular pathways governing the life cycle of arbuscular mycorrhizal (AM) fungi and their symbiotic interactions with root tissues are not yet fully understood. Most studies fo fungal responses to host plants have targeted developmental stages before root contact (germinating spores), or after root colonization (intraradical mycelium). We are focusing on the early cell events of appressoria contact with the root surface which are essential to the successful outcome of the AM symbiosis. Recent monitoring of Glomus intraradices gene expression at this stage has revealed differential fungal responses to roots of host and non-host (Myc- mutants) M. truncatula (Seddas et…
Membrane dynamics of sugar transports in tobacco-microbe interactions
2017
SPEINRAUBIPM DOCT; Plants can influence microorganism population through exudation of sugars notably as carbon source. Indeed, the type of plant-microorganism interaction (PMI) is linked to the trophic exchanges between plant and microorganism. Microorganisms are thus able to “manipulate” the host to modify sugar fluxes. In mycorrhizal symbiosis, the plant has a supply of nutrients by the fungal partner, which in return receives sugars. In pathogenic relationship, the microorganism will divert sugars provided by the plant without compensation. Despite identification of sugar transporters at biotrophic interfaces, molecular and cellular mechanisms by which microorganisms operate the distribu…
Legacy effects of contrasting water and N-availability patterns on plantmicrobial response to rewetting
2019
National audience; Introduction. Shifts in the frequency and magnitude of rain events (precipitation regime) associated with climate change may affect plant morphological and physiological strategies as well as soil microbial activity.Objectives. The objective of this study was to determine i) how precipitation history shapes the response dynamics of soil bacterial and fungal communities to rewetting, as well as plant-microbial competition for N, and ii) how the N status of the system may modulate the effect of precipitation regime.Materials & methods. The legacy effects of 12 weeks of contrasting precipitation (frequent or infrequent watering, equal total water input) and N inputs was asse…
Qu'est-ce que les bandes enherbées? conséquences environnementales et biologiques
2009
National audience
Effets des interactions entre diversité végétale inter et intraspécifique et communautés microbiennes du sol sur les propriétés de l’écosystème - Can…
2019
National audience; Le lien entre diversité et fonctionnement d’un écosystème ainsi que les mécanismes sous-jacents sont très étudiés en génétique des populations et en écologie des communautés et des écosystèmes. La première s’attèle à décrire les effets de la variabilité génétique intraspécifique sur différentes propriétés écosystémiques tandis que la deuxième s’intéresse aux interactions écologiques au niveau interspécifique. Notre objectif est de faire le lien entre ces deux champs disciplinaires par l’étude des effets conjoints d’une mobilisation de la diversité végétale intra et interspécifique et de la diversité microbienne sur les propriétés de l’écosystème. Nous avons mesuré différe…
Modéliser les couverts cultures : adventices pour étudier le rôle de la diversification des cultures dans les systèmes de culture agro écologiques
2019
National audience; La diversification des cultures est un levier majeur de gestion agroécologique des bioagresseurs. Ce papier illustre avec l'exemple de FLORSYS le rôle des modèles mécanistes de dynamique des adventices pour synthétiser les connaissances, les appliquer à la conception de systèmes de culture, et les transférer vers les acteurs. Des cas d'étude illustrent comment ce modèle sert à évaluer et promouvoir les bénéfices de la diversification des cultures en (1) identifiant les caractéristiques de cultures qui seraient idéales ("idéotypes") pour la gestion agroécologique des adventices, (2) traquant des stratégies de gestion basées sur la diversification des cultures dans des rése…
L’organisation spatiale du paysage : un levier d’action pour promouvoir le service de prédation des graines d’adventices par les carabidés ?
2014
National audience; Le contexte actuel engage à développer une agriculture durable et entre autres de favoriser des services écosystémiques comme la régulation biologique des bio-agresseurs par des auxiliaires de cultures. Parmi les processus impliqués dans ces régulations biologiques, la prédation des graines d’adventices par les coléoptères carabidés opère de façon générique dans les parcelles cultivées et peut être considérée comme un service écosystémique. Elle résulte de l’action de certaines espèces ‘granivores’ spécialistes souvent peu abondantes dans les champs ainsi que de l’action d’espèces omnivores pour lesquelles les graines d’adventices peuvent représenter une ressource alterna…