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PSDR4 ProSys -Soil and climate adaptation, environmental impacts and economic value of new sustainable protein-producing cropping systems in Burgundy Franche-Comté
No full textThis issue brings together texts from projects carried out as part of the research programme : For Regional Development’4, under the aegis of INRAE and 10 French Regions.National audienceThe ProSys project aimed to identify agronomically efficient protein-based cropping systems that can adapt to the context of climate change, meet environmental challenges, are economically viable and represent an acceptable alternative for farmers and the industry. The potential of production and environmental constraints encountered by legumes, under current conditions and in the context of climate change, were studied. In addition, an experiment was conducted to study the previous effect of different legume species. An innovation tracking has allowed to identify and analyze protein-producing cropping systems that have been tested by farmers in the region who are satisfied with them. The positive environmental impacts and the interest for the global production of proteins of cropping systems with legumes were evaluated through long-term experimental follow-ups. Finally, the modalities of changing farmers' practices towards plant protein producing systems were analyzed. The creation of working groups with agricultural education and professionals from the agricultural world has enabled the development of a set of tools and communication media to promote the results of the project
Fibrobacter sp. HC4, a newly isolated strain, demonstrates a high cellulolytic activity as revealed by enzymatic measurements and in vitro assay
No full textInternational audienceDespite their low quantity and abundance, the cellulolytic bacteria that inhabit the equine large intestine are vital to their host, as they enable the crucial use of forage-based diets. Fibrobacter succinogenes is one of the most important intestinal cellulolytic bacteria. In this study, Fibrobacter sp. HC4, one cellulolytic strain newly isolated from the horse cecum, was characterized for its ability to utilize plant cell wall fibers. Fibrobacter sp. HC4 consumed only cellulose, cellobiose, and glucose and produced succinate and acetate in equal amounts. Among genes coding for CAZymes, 26% of the detected glycoside hydrolases (GHs) were involved in cellulolysis. These cellulases belong to the GH5, GH8, GH9, GH44, GH45, and GH51 families. Both carboxymethyl cellulase and xylanase activities of Fibrobacter sp. HC4 were detected using the Congo red method and were higher than those of F. succinogenes S85, the type strain. The in vitro addition of Fibrobacter sp. HC4 to a fecal microbial ecosystem of horses with large intestinal acidosis significantly enhanced fibrolytic activity as measured by the increase in gas and volatile fatty acids production during the first 48 h. According to this, the pH decreased and the disappearance of dry matter increased at a faster rate with Fibrobacter sp. HC4. Our data suggest a high specialization of the new strain in cellulose degradation. Such a strain could be of interest for future exploitation of its probiotic potential, which needs to be further determined by in vivo studies. IMPORTANCE Cellulose is the most abundant of plant cell wall fiber and can only be degraded by the large intestine microbiota, resulting in the production of volatile fatty acids that are essential for the host nutrition and health. Consequently, cellulolytic bacteria are of major importance to herbivores. However, these bacteria are challenged by various factors, such as high starch diets, which acidify the ecosystem and reduce their numbers and activity. This can lead to an imbalance in the gut microbiota and digestive problems such as colic, a major cause of mortality in horses. In this work, we characterized a newly isolated cellulolytic strain, Fibrobacter sp. HC4, from the equine intestinal microbiota. Due to its high cellulolytic capacity, reintroduction of this strain into an equine fecal ecosystem stimulates hay fermentation in vitro . Isolating and describing cellulolytic bacteria is a prerequisite for using them as probiotics to restore intestinal balance
Évaluation multicritère de systèmes de culture en agriculture de conservation des sols : le cas du réseau Dephy Ferme
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Chapter 11 : Multi-Dimensional Models for Spatial Panels
No full textInternational audienceSpatial econometric models are widely used to formalize interactions in geographical space or along networks. When applied to panel data, the methodologies and specifications developed are mainly related to two-dimensional approaches that refer to observations on a cross-section of households, firms, countries, etc. over several time periods. However, lots of data exhibit more complex multi-dimensional structures that can be non-hierarchical or hierarchical. The multi-dimensional models that are not necessarily connected to a hierarchical structure are described in Chapters 12 and 14. Therefore, this chapter mostly considers the case of hierarchical multidimensional spatial panels. Focusing on static panel data models, we organize all this recent literature, provide an encompassing specification, and emphasize a range of issues pertaining to the specification, estimation, testing procedures and prediction for these models. These issues include a mixture of usual topics on panel data, i.e., the form taken by individual and temporal heterogeneity, or topics more specific to spatial econometrics, i.e., dependence among observations across space, structures of the spatial matrix, Maximum Likelihood (ML) and Generalized Moments (GM) approaches, determination and inference of direct and indirect (or spillover) effects. The last section considers a range of possible extensions
Digestats de méthanisation et qualité biologique des sols agricoles : Impact des digestats de méthanisation sur la qualité biologique des sols. Metha-BioSol (APR GRAINE)
No full textDans un contexte d’amélioration de la gestion agroécologique des sols afin d’optimiser leur capacité de production pour une agriculture plus écoefficiente, le projet Metha-BioSol a cherché à évaluer l’impact des digestats de méthanisation sur la qualité biologique et écologique des sols en utilisant des bio-indicateurs opérationnels, c’est-à-dire des outils permettant d’appréhender la diversité des macro et micro-organismes, la dynamique du carbone (C) et l’état sanitaire (pathogènes) des sols. Ce projet répond à des interrogations de plus en plus nombreuses d’agriculteurs engagés dans une valorisation des déchets organiques par une démarche de méthanisation de leurs effluents d’élevage ou résidus de culture. Il a permis de générer des données quant à l’impact des digestats de méthanisation sur la qualité biologique et écologique des sols agricoles.Le projet Metha-BioSol s‘articule en deux étapes successives : 1. au laboratoire, en milieu contrôlé (incubation de méso-microcosmes de sol). Il ’agissait de tester différents types de digestats (composition différente) sur différents types de sols. L’objectif était d’évaluer l’impact des digestats de méthanisation sur la qualité biologique des sols, sur le court terme (un seul apport, pas de récurrence des apports). Les résultats obtenus ont permis de montrer que la réponse des bio-indicateurs à un digestat était dépendante du type de digestat apporté et du contexte pédoclimatique. 2. sur le terrain, via des prélèvements de sols effectués sur des sites expérimentaux de longue durée. Les sites retenus étaient ceux du SOERE-PRO (EFELE et PROspective) et du lycée Agricole d’Obernai (DIGE’O). Ces sites présentent des contextes pédoclimatiques différents (océanique (Bretagne) vs continental (Alsace)) et épandent de façon récurrente, depuis plusieurs années déjà, des types de digestat variés et caractéristiques des activités de leur territoire d’appartenance. Les résultats obtenus ont montré que la réponse des bio-indicateurs de la qualité biologique des sols aux apports de digestats de méthanisation dépendait de la récurrence des apports. En effet, au bout de 8 à 10 campagnes d’apports de digestat, la biologie des sols s’avérait être différente de celle ayant reçu un fumier classique ou une fertilisation minérale.La combinaison de ces deux approches a permis :1. de mieux renseigner l’impact des digestats de méthanisation sur la qualité biologique des sols sur le court et le moyen terme2. d’évaluer l’importance du type de digestat et du contexte pédoclimatique dans cet impact. In fine, ce projet a permis de générer des données permettant d’évaluer de façon plus objective et robuste l’impact des digestats de méthanisation sur la qualité biologique et écologique des sols
Analyse par imagerie multi-echelles de l’interaction entre la plante parasite Phelipanche Ramosa et une souche de champignon pathogène d’origine tellurique
No full textInternational audiencePhelipanche ramosa (L.) Pomel, branched broomrape of winter oilseed rapeBrassica napus L., is a parasitic weed that needs a host plant to develop.The parasitic lifestyle requires a close relationship with the host plant fromthe earliest stages of development. This parasitic plant has been causingsignificant yield losses in rapeseed crops in France for some thirty years.Cryogenic scanning electron microscopy (cryo-SEM), transmission electronmicroscopy (TEM) and confocal laser scanning microscopy (CLSM) techniqueswere used to assess how the colonization of the parasitic plant by a pathogenicfungal strain affected the integrity of the plant tissues. Our observationsreveal a particularly reticulated parasite seed coat, composed of voluminousdehydrated cells forming a set of irregular alveoli. The outer walls of thesecells have collapsed and are joined to the inner walls, which have thinnedto form numerous punctuations. While the orange auto-fluorescence revealsthe seed coat with CLSM, green auto-fluorescence reveals soil debris on thesurface of the outer wall, as well as the presence of albumen and embryobeneath the seed coat. Interaction of the seed with the Fusarium strain leadsto structural changes, as revealed by cryo-SEM observations. These includemore pronounced cross-linking, increased punctuation and collapse ofthe seed tissue. These observations also reveal mycelial filaments runningthrough the integument, reflecting the development of the fungal strain. InMET, the pathogenicity of the fungal strain can be observed in the crushingand less clear contours of the tissues of the young P. ramosa tuber. A large number of fungal spores are found in the seed coat and in the peripheral cellsof the seed albumen, while fungal material fills the xylem of P. ramosa and theintercellular spaces of the haustorium tissues. Finally, the starch grains initiallypresent in P. ramosa tissues are less numerous and deteriorated, probablyexploited by the fungal strain. The results obtained indicate that the approachfollowed makes it possible to understand in detail and at the cytological levelthe mechanisms of the pathogenic fungus-parasitic plant interaction. Theyalso validate the relevance of the analysis by multi-scale imaging of thisinteraction to acquire the required knowledge to consider the biocontrol ofthe parasitic plant P. ramosa by soil-borne pathogenic fungi.Phelipanche ramosa (L.) Pomel, l’orobanche rameuse du colza d’hiver Brassica napus L., est une plante adventice parasite qui a besoin d’une plante hôte pour se développer. Le mode de vie parasite nécessite une relation étroite avec la plante hôte dès les premiers stades de développement. Cette plante parasite entraîne des pertes importantes de rendement dans les cultures de colza en France depuis une trentaine d’années. Les techniques de cryo-microscopie électronique à balayage (cryo-MEB), de microscopie électronique à transmission (MET) et de microscopie confocale à balayage laser (MCBL) ont été utilisées pour tenter d’apprécier en quoi, la colonisation de la plante parasite par une souche fongique pathogène affectait l’intégrité des tissus de cette plante. Nos observations révèlent un tégument de la graine du parasite particulièrement réticulé, composé de volumineuses cellules déshydratées formant un ensemble d’alvéoles irrégulières. Les parois externes de ces cellules sont effondrées et s’accolent aux parois internes qui s’amincissent pour former de nombreuses ponctuations. Si l’auto-fluorescence orange révèle le tégument au MCBL, l’auto-fluorescence verte permet de visualiser les débris du sol à la surface de la paroi externe ainsi que la présence de l’albumen et de l’embryon sous le tégument de la graine. L’interaction de la graine avec la souche de Fusarium entraine des modifications structurales mises en évidence par les observations en cryoMEB. Il s’agit notamment de réticulations plus marquées, de ponctuations plus nombreuses et d’un affaissement des tissus de la graine. Ces observations révèlent également des filaments mycéliens traversant le tégument et traduisant le développement de la souche fongique. En MET, la pathogénicité de la souche fongique est observable par un écrasement et des contours moins nets des tissus du jeune tubercule P.ramosa. Dans le tégument ainsi que dans les cellules périphériques de l’albumen de la graine, un grand nombre de spores de champignons est retrouvé tandis que du matériel fongique remplit le xylème de P. ramosa ainsi que les espaces intercellulaires des tissus de l’haustorium. Enfin, les grains d’amidon initialement présents dans les tissus de P. ramosa sont moins nombreux et détériorés, probablement exploités par la souche fongique. Les résultats obtenus indiquent que l’approche suivie permet d’appréhender finement et au niveau cytologique, les mécanismes de l’interaction champignon pathogène-plante parasite. Ils valident également la pertinence de l’analyse par imagerie multi-échelles de cette interaction pour acquérir les connaissances nécessaires et envisager le biocontrôle de la plante parasite P. ramosa par des champignons pathogènes d’origine tellurique
« Enseigner à produire autrement », ou comment le travail et l’image des enseignants et formateurs sont bousculés
No full textInternational audienceThe strategic plan for Agricultural education “Teaching to produce differently” (EPA1, 2014-2018 and EPA2, 2020-2024) is a very ambitious plan, which aims, from a political point of view, to transform both the agricultural production system and the training system itself. As actors in the National support system for agricultural technical education and researchers in education and training sciences, we are interested in how this prescription is appropriated and implemented in the teaching-learning situations proposed by teachers and trainers (Gaborieau & Peltier, 2019). This research note first explains how this plan represents a real paradigm shift for teacher-trainers in terms of the agricultural model and the teaching-learning model. It then seeks to identify the reasons why teacher trainers are struggling to take full advantage of the plan. Finally, it proposes to question the work of the researcher-intervenor in order to support these same actors in the transformation of their training model towards a model combining the constructive and productive dimensions of learning.Le plan stratégique « Enseigner à produire autrement » (EPA1, 2014-2018 et EPA2, 2020-2024) constitue un plan très ambitieux, qui vise, d’un point de vue politique, des transformations tant du système de production agricole que du système de formation lui-même. Parties prenantes du Dispositif national d’appui à l’enseignement agricole technique et chercheurs en sciences de l’éducation et de la formation, nous nous intéressons à la manière dont, dans les situations d’enseignement-apprentissage que proposent les enseignants et les formateurs, cette prescription est appropriée et mise en œuvre (Gaborieau & Peltier, 2019). Cette note de recherche précise tout d’abord en quoi ce plan constitue un véritable changement de paradigme pour les enseignants-formateurs en termes de modèle agricole ainsi que de modèle d’enseignement-apprentissage. Elle cherche ensuite à identifier les raisons des difficultés des enseignants-formateurs à s’en saisir pleinement. Elle propose enfin de questionner le travail du chercheur-intervenant afin d’accompagner ces mêmes acteurs dans la transformation de leur modèle de formation vers un modèle alliant dimension constructive et dimension productive des apprentissages
Insights to Study, Understand and Manage Extruded Dry Pet Food Palatability
No full textThis article belongs to the Section Companion Animals (https://www.mdpi.com/journal/animals/sections/Companion_animals)International audiencePet food production is a fast-growing industry. While extruded dry pet food is the favored pet food due to its convenience of use, it may have poorer palatability than other pet foods such as wet pet foods. However, palatability plays a pivotal role in meeting nutritional requirements or providing therapeutic benefits in cats and dogs, as it ensures food acceptance. Thus, both academics and manufacturers conduct routine palatability tests to assess acceptance and preference of products among pets, alongside sensory analyses involving human panels. Palatability is greatly influenced by species-specific and environmental factors in cats and dogs. The review will hence present the current knowledge on palatability assessment and animal food perception; it will then aim to explore strategies for effectively managing palatability in dry pet food by examining the impact of key ingredients and process parameters on the finished product’s palatability. Moreover, the demands and needs for sustainable and healthier products as well as supply constraints present novel challenges and opportunities for academics and manufacturers
« Récolter ses usages » et construire son expérience d’activité médiatisée
No full textInternational audienceThe article looks at the uses and effects of using digital technology to learn and to help people learn. The authors bring together the notional pairs of use/conception and experience/experience. The situations of use are collected using digital experience books designed to structure and guide the contributions of the collectors. They are invited to record the situation they have experienced, describing how it unfolded, the resources mobilised, the difficulties, tricks and futures imagined for the situation.L’article étudie les usages et les effets des usages du numérique pour apprendre et faire apprendre. Les auteures font dialoguer les couples notionnels usage/conception et vécu/expérience. La récolte des situations d’usage est réalisée au moyen de carnets d’expériences numérisés conçus pour structurer et guider les contributions des récolteurs. Ces derniers sont ainsi invités à consigner la situation vécue en décrivant son déroulement, les ressources mobilisées, les difficultés, astuces et futurs imaginés pour la situation
1H NMR based sulfonation reaction kinetics of wine relevant thiols in comparison with known carbonyls
No full textInternational audienceSulfite addition is a common tool for ensuring wines' oxidative stability via the activity of its free and weakly bound molecular fraction. As a nucleophile, bisulfite forms covalent adducts with wine's most relevant electrophiles, such as carbonyls, polyphenols, and thiols. The equilibrium in these reactions is often represented as dissociation rather than formation. Recent studies from our laboratory demonstrate, first, the acetaldehyde sulfonate dissociation, and second, the chemical stability of cysteine and epicatechin sulfonates under wine aging conditions. Thus, the objective of this study was to monitor by 1H NMR the binding specificity of known carbonyl-derived SO2 binders (acetaldehyde and pyruvic acid) in the presence of S-containing compounds (cysteine and glutathione). We report that during simulated wine aging, the sulfur dioxide that is rapidly bound to carbonyl compounds will be released and will bind to cysteine and glutathione, demonstrating the long-term sulfur dioxide binding potential of S-containing compounds. These results are meant to serve as a complement to existing literature reviews focused on molecular markers related to wines' oxidative stability and emphasize once more the importance of S-containing compounds in wine aging chemical mechanisms