Search results for "Vegetal Biology"

Carbohydrates in plant immunity and plant protection: roles and potential application as foliar sprays.

2014

International audience; Increasing interest is devoted to carbohydrates for their roles in plant immunity. Some of them are elicitors of plant defenses whereas other ones act as signaling molecules in a manner similar to phytohormones. This review first describes the main classes of carbohydrates associated to plant immunity, their role and mode of action. More precisely, the state of the art about perception of "PAMP, MAMP, and DAMP (Pathogen-, Microbe-, Damage-Associated Molecular Patterns) type" oligosaccharides is presented and examples of induced defense events are provided. A particular attention is paid to the structure/activity relationships of these compounds. The role of sugars as…

Microorganisms and Biotic Interactions

2014

SPE IPM; Most ecosystems are populated by a large number of diversified microorganisms, which interact with one another and form complex interaction networks. In addition, some of these microorganisms may colonize the surface or internal parts of plants and animals, thereby providing an additional level of interaction complexity. These microbial relations range from intraspecific to interspecific interactions, and from simple short-term interactions to intricate long-term ones. They have played a key role in the formation of plant and animal kingdoms, often resulting in coevolution; they control the size, activity level, and diversity patterns of microbial communities. Therefore, they modul…

Effect of inter-individual variability and intraguild interferences on the foraging strategies of seed-eating carabid species

2017

Making a choice requires, implicitly, an investment of time in one behaviour at the expense of an investment in another. Being choosy would increase the risk of losing many food item opportunities to competitors, and is directly in conflict with other essential tasks such as predator avoidance. Individuals are thus expected to adjust their level of choosiness in response to the competition and predation context. The available behavioural ecological theory and the empirical ecology of carabids would suggest that competition and predation interference induces changes in the foraging behaviour of carabid individuals. Carabids typically operate within communities in which competition and predat…

Evaluation of the effect of an additional fertilizer on the dynamics of microbial community and the decomposition of organic matter in soil

2012

Organic matter (OM) influences many of the soil functions and occupies a central position in the global carbon cycle. At the scale of the agro-ecosystem, primary productivity is dependent on the recycling of soil organic matter (SOM) by the action of decomposers (mainly bacteria and fungi), which mineralize organic compounds, releasing the nutrients needed for plant growth. At a global scale, the recycling of the SOM determines the carbon flux between soil and atmosphere, with major consequences in terms of environmental quality. In this context, the management of SOM stocks in agro-ecosystems is a major issue from which depend the maintenance of the productivity and sustainability of agric…

Réponses de la plante et des microorganismes du sol aux changements environnementaux

2015

Dynamique membranaire dans les réponses précoces des cellules de tabac à la cryptogéine

2015

Utilisation du potentiel de biodégradation de sédiments de rivière comme indicateur d’une diminution du niveau d’exposition a l’herbicide diuron suit…

2013

National audience; Les communautés microbiennes présentent une forte capacité à répondre rapidement à des changements environnementaux et à s’y adapter de manière transitoire ou irréversible. En cas d’exposition chronique à des polluants organiques, les processus d’adaptation microbienne peuvent ainsi conduire à l’amélioration des capacités de biodégradation de ces composés. Cette fonctionnalité concerne principalement les microorganismes hétérotrophes (essentiellement les bactéries et les champignons) capables de dégrader les polluants (totalement ou partiellement) pour les utiliser comme une source d’énergie et de nutriments pour leur croissance. Plusieurs études réalisées en milieu terre…

Dynamics of changes in the soil organic matter, functional diversity and C and N fluxes after shift in agricultural practices of an annual crops rota…

2015

International audience; Introduction and objectives Agricultural practices (e.g. crop rotation, tillage) lead to profound changes in soil properties, ecosystem structure (e.g. biodiversity) and functioning (e.g. ecosystem services). Whereas this has been very often characterized in the medium and long terms, little is known so far about how fast soil properties respond to changing practices at the time scale (year to several years) in which farmers take their decision in the management of their crops. In agricultural systems, increasing consideration is given to soil biodiversity, whose role has long been overlooked by agronomists, but whose preservation in now recognized as key for maintai…

Ecosystem Services: From Biodiversity to Society, Part 2

2016

SPE Pôle GESTAD; International audience

Différents modes de production

2012

Les productions générées par les exploitations agricoles sont organisées en système de production qui désigne « l’ensemble structuré des facteurs de production combinés entre eux pour assurer une production végétale et/ou animale en vue de satisfaire les objectifs de l’exploitant agricole ». Les systèmes de production sont souvent décrits par les OTEX (orientations technico-économiques des exploitations) sur une base économique de classification, mais il existe égalementdes descriptions fonctionnelles fréquemment utilisées parles instituts techniques sur la base des facteurs de production et de leur combinaison. Dans les exploitations françaises, la production d’herbivores (bovins, ovins, c…