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Agroecology Territories, a participatory action research project for transition towards sustainable and territorialized agricultural food systems (2013-2018)
No full textInternational audienc
Caractériser les formes d'interaction entre filières agricoles et territoires : quelles méthodes ?
No full text[Departement_IRSTEA]Territoires [TR1_IRSTEA]DTAMGlobalization comes along with an important restructuring of the agricultural value chains,resulting in an ever more important disconnection between operators of the supply chains and those of theterritories, and between production sites and use of local resources.Operators of supply chains, whichmake useof local resources, often operate only a small part of their activity locally and do not always care about theirenvironmental or socioeconomic impacts. There is a major challenge to reconnect supply chains’ andecosystems’ dynamics at territory level.First, it requires understanding the types of interactions between supplychains and territories, to be able to design pathways for their sustainable co-evolution. We developed ananalytical framework presenting forms of interactions between supply chains and territories, questioning thetypes of: anchoring of the agricultural activities in territories; dependence of territories to exogenous resources,operators or territories; footprints of the agricultural activities on local territory or on the rest of the world.Wepropose here a review of existing methods handling these different dimensions and their versions according tothe considered issue: environmental or socioeconomic. Biophysical and socioeconomic approaches remainlargely separated, what brings us to discuss the scientific gap to fill for reaching operational effectiveness of apotential integrative approach, while avoiding the pitfall of “localism”.Le processus de globalisation s’accompagne d’une importante restructuration des filièresagricoles, se traduisant par une déconnexion de plus en plus forte entre opérateurs des filières et ceux desterritoires, et entre lieux de production et usages des ressources locales. Les opérateurs des filières utilisent desressources des territoires, mais n’y opèrent souvent qu’une partie de leur activité, et ne se soucient pas toujoursde leur impact local, environnemental comme socioéconomique. Il y a un réel enjeu socioécologique àreconnecter les dynamiques des filières agricoles à celles des écosystèmes, à l’échelle des territoires, là où lesactivités de production prennent place. Pour cela, il est nécessaire de comprendre au préalable les formesd’interaction entre filières et territoires, pour pouvoir ensuite agir dans une perspective de développementdurable. Nous avons élaboré un cadre d’analyse des formes d’interaction entre filières et territoires,interrogeant les formes d’ancrage des filières agricoles aux territoires, les formes de dépendance des territoires,pour leurs filières, vis-à-vis de ressources et opérateurs exogènes, ou d’autres territoires, enfin les formesd’empreinte des filières agricoles pour les territoires ou de la production agricole du territoire pour le reste dumonde.Nous proposons ici une revue ciblée de la littérature sur les différentes méthodes existantes permettantde traiter ces différentes dimensions et leurs déclinaisons selon l’enjeu considéré : environnemental ousocioéconomique. Les approches biophysiques d’un côté et socioéconomiques de l’autre restent largementdissociées, ce qui nous amène à discuter de l’opérationnalité de ce tour d’horizon pour la communautéscientifique. Nous formulons également quelques recommandations, notamment pour éviter l’écueil du« localisme »
Complémentarités territoriales entre culture et élevage, entre action collective et contraintes organisationnelles
No full textInternational audienceCollaboration among grain-growers and livestock farmers makes it possible to tackle challenges related to feed autonomy in organic livestock systems. It also facilitates organic fertilisation in organic grain-growing systems. Such collaborations vary in their intensity, challenges, and benefits. Here, we explored 3 case studies involving partnerships between crop and livestock farmers. We looked at the following: i) partnership establishment; ii) the creation of an online tool for exchanging products; and iii) means for evaluating existing product exchanges. In all 3 cases, we observed a strong degree of complementarity between organic cash-crop farms and livestock farms within regions. However, we also noted the presence of logistical and organisational constraints that occurred during the establishment period. We propose a roadmap that could help guide farmers that wish to engage in such collaborations, which must bring in different economic and political stakeholders from the region.Pour répondre aux enjeux d'autonomie alimentaire en élevage biologique, mais aussi de fertilisation organique en céréaliculture biologique, la coopération céréaliers-éleveurs semble une voie prometteuse pour une gestion durable. Comment renforcer les complémentarités entre systèmes, par des connexions entre exploitations échangeant des produits ? Les relations cultures-élevage de coopération entre fermes spécialisées présentent des intensités, des enjeux et des bénéfices variés. Trois cas d'échanges céréaliers-éleveurs sont étudiés : i) la construction de scénarios d'échanges, ii) la mise en place d'une plate-forme en ligne pour l'échange de produits et iii) l'évaluation des performances de flux de produits déjà existants. Ces cas montrent à la fois la forte complémentarité entre grandes cultures et élevage biologiques dans les territoires, mais aussi les contraintes logistiques et organisationnelles lors de la mise en œuvre. Une feuille de route est proposée pour l'accompagnement de projets d'échanges céréaliers-éleveurs, qui doivent impliquer différents acteurs économiques et politiques des territoires
Agroecological Principles and Practices for Grass-Based Farming Systems
No full textInternational audienc
Gérer les adventices dans les systèmes de grandes cultures biologiques - Retour d’expériences du Réseau RotAB ITAB
No full textNational audienc
Intercropping with legume for agroecological cropping systems: complementarity and facilitation processes and the importance of soil microorganisms. A review
No full textInternational audienceIntercropping is a powerful way to promote a more diversified plant community in the field, thereby enabling complementary and facilitative relationships. In these systems, legumes are a key functional group, and are highly valued for the agroecological services they provide. This review identifies the different complementarity and facilitation processes in soils in intercropped legume/cereal systems and the key role of soil microorganisms in these processes. The intercropped legumes/cereal systems reduce inter-specific competition by enhancing complementarity/facilitation processes thereby improving the exploitation of resources, which is, in turn, reflected in the increase in plant production corresponding to greater efficiency of the agroecosystem as a whole. Plant production, including above-and belowground biomass, is positively correlated with microbial abundance and diversity. This microbial life is assumed to play a significant role in the availability and transfer of soil nutrients to plants as well as in plant health and soil fertility. Although we are currently unable to identify a reliable and exhaustive pattern of plant-microbe interactions, perhaps simply because no universal relationship exists between plants and microorganisms, reliable scenarios reveal strong trends and define the conditions required for successful intercropping systems and microbial interactions. Given our incomplete knowledge of facilitation processes and belowground interactions, intercropping systems must learn from and apply the experience gained in successful experiments. Intercropping dynamics play a critical role in explaining the establishment of facilitative root interactions and finally suggest perennial plant associations may be more effective than annual ones
Reprogramming of rabbit induced pluripotent stem cells toward epiblast and chimeric competency using Krüppel-like factors
No full textRabbit induced pluripotent stem cells (rbiPSCs) possess the characteristic features of primed pluripotency as defined in rodents and primates. In the present study, we reprogrammed rbiPSCs using human Krüppel-like factors (KLFs) 2 and 4 and cultured them in a medium supplemented with fetal calf serum and leukemia inhibitory factor. These cells (designated rbEKA) were propagated by enzymatic dissociation for at least 30 passages, during which they maintained a normal karyotype. This new culturing protocol resulted in transcriptional and epigenetic reconfiguration, as substantiated by the expression of transcription factors and the presence of histone modifications associated with naïve pluripotency. Furthermore, microarray analysis of rbiPSCs, rbEKA cells, rabbit ICM cells, and rabbit epiblast showed that the global gene expression profile of the reprogrammed rbiPSCs was more similar to that of rabbit ICM and epiblast cells. Injection of rbEKA cells into 8-cell stage rabbit embryos resulted in extensive colonization of ICM in 9% early-blastocysts (E3.5), epiblast in 10% mid-blastocysts (E4.5), and embryonic disk in 1.4% pre-gastrulae (E6). Thus, these results indicate that KLF2 and KLF4 triggered the conversion of rbiPSCs into epiblast-like, embryo colonization-competent PSCs. Our results highlight some of the requirements to achieve bona fide chimeric competency
Agroecological practices for sustainable agriculture: principles, applications, and making the transition
No full textInternational audienceGood agroecological practices are indispensable for the development of sustainable agriculture. In this book, principles, diversity and applications of agroecological practices for a range of systems are presented, transforming scientific research and participatory knowledge of production into practical application. It illustrates a broad range of research and teaching being used within the farming community to demonstrate best practice and current state-of-play within the field. Agroecological methods used in crop farming, grass-based livestock farming, fish production, and other complex farming systems are discussed. Conclusions are drawn from studies to provide an outlook on future trends of agroecological practices and on policies supporting implementation.Due to emphasis on real-life application, it is relevant not only to students of the agricultural sciences and public policy, but also to researchers, stakeholders and policy makers involved in the development of sustainable agriculture
Ice nucleating agents allow embryo freezing without manual seeding
No full textInternational audienceEmbryo slow freezing protocols include a nucleation induction step called manual seeding. This step is time consuming, manipulator dependent and hard to standardize. It requires access to samples, which is not always possible within the configuration of systems, such as differential scanning calorimeters or cryomicroscopes. Ice nucleation can be induced by other methods, e.g., by the use of ice nucleating agents. Snomax is a commercial preparation of inactivated proteins extracted from Pseudomonas syringae. The aim of our study was to investigate if Snomax can be an alternative to manual seeding in the slow freezing of mouse embryos. The influence of Snomax on the pH and osmolality of the freezing medium was evaluated. In vitro development (blastocyst formation and hatching rates) of fresh embryos exposed to Snomax and embryo cryopreserved with and without Snomax was assessed. The mitochondrial activity of frozen-thawed blastocysts was assessed by JC-1 fluorescent staining. Snomax didn't alter the physicochemical properties of the freezing medium, and did not affect embryo development of fresh embryos. After cryopreservation, the substitution of manual seeding by the ice nucleating agent (INA) Snomax did not affect embryo development or embryo mitochondrial activity. In conclusion, Snomax seems to be an effective ice nucleating agent for the slow freezing of mouse embryos. Snomax can also be a valuable alternative to manual seeding in research protocols in which manual seeding cannot be performed (i.e., differential scanning calorimetry and cryomicroscopy)