Les ateliers agrifood : Reconnecter la recherche sur la production agricole et la transformation alimentaire

Rapport IDEAS-INRA-AgroParisTechLes ateliers agrifood : Conception d’un agenda de recherche partagé pour des systèmes agri-alimentaires plus sains et plus durable

Grain legume-cereal intercropping enhances the use of soil-derived and biologically fixed nitrogen in temperate agroecosystems: a meta-analysis

Grain legumes are known for their benefits to deliver ecosystem services on provisioning of protein-rich food and feed, reducing greenhouse gas emissions through the symbiotic nitrogen fixation function and diversification of cropping systems. Intercropping is an agroecological practice in which two or more crop species are grown simultaneously in the same field, thereby maximizing the use of resources to enhance yields in low input systemsand the resilience of cropping systems. We quantified the effect of grain legume-cereal intercropping on the useof N resources in temperate agroecosystems, focusing on dinitrogen (N2) fixation and soil-derived nitrogenacquisition using a meta-analysis of 29 field-scale studies. We estimated and compared effects of different intercrop compositions (proportion of each species in the intercrops), fertilization rates, crop species, soil properties, and other management practices on the symbiotic N2 fixation and the acquisition of soil-derived nitrogenby the cereals and grain legumes. The proportion of N derived from N2 fixation was on average 14 % (95 % CI =[11, 16]) higher in intercropped grain legumes (76 %) compared to legume sole crops (66 %). On the other hand,intercropping reduced the amount of N2 fixed (kg ha−1) by about 15 %, when N2 fixation in inter- and solecropped legumes was expressed at equivalent density by compensating for the sown legume proportion in intercrops relative to their sole crop sowing rate. The results were mainly influenced by the intercrop composition,legumes species and the method used to quantify N2 fixation. Soil-derived nitrogen acquisition in intercroppedgrain legumes was significantly reduced (−47 %, 95 % CI = [−56, −36]) compared to sole crop legumes,expressed at equivalent density, while the soil N acquired by intercropped cereals was much higher (+61 %, 95% CI = [24, 108]) than in sole crop cereals. Total soil N acquisition (legume + cereal) was significantly higherin intercrops than in legume sole crops (+25 %, 95 % CI = [1, 54]), while there was no significant differencebetween intercrops and cereal sole crops. The meta-analysis confirms and highlights that intercropping consistently stimulates complementary N use between legumes and cereals by increasing N2 fixation by grain legumes and increasing soil N acquisition in cereals. Based on the results of this analysis it would be suggested thatcropping systems diversification via intercropping can be used for simultaneous production of both cereals andgrain legumes, while increasing the use of N-sources and reducing external inputs of N fertilizers, thereby enhancing the sustainability of agriculture

Co-conception et évaluation de scénarios agronomiques de réintroduction de légumineuses dans un territoire de Bourgogne

Ce numéro est constitué d’articles issus de la seconde édition des Rencontres Francophones sur les Légumineuses (RFL2) qui s’est tenu à Toulouse (France) les 17 et 18 octobre 2018.Legume crops can help facing current environmental and food challenges, even if their areas havedecreased since several decades. The aims of our study were (i) to design with local stakeholdersagronomic scenarios of reintroduction of legumes into a French territory, (ii) to assess these scenariosex ante, and (iii) to discuss with the stakeholders the interest and conditions of their adoption in theterritory. The stakeholders involved were agricultural stakeholders (farmers, technical advisors),stakeholders from environmental organizations (water union, national park) and researchersThe first step was the description and assessment of current and alternative crop management plans,from national statistical data and face-to-face surveys. In a second step, the current territory (cropdistribution in the territory and cropping strategies) was described with local stakeholders, and was usedas a reference. In a third step, stakeholders discussed various sets of objectives and constraints relatedto their territory. Among eight scenarios proposed by stakeholders, four scenarios were simulated withthe tool used in the Coclick’eau approach. For each scenario, this tool optimizes an alternativedistribution of crops and cropping strategies, and assesses the agronomic, socio-economic andenvironmental performances. Finally, the results were discussed with stakeholders.Les légumineuses peuvent contribuer à relever les défis environnementaux et alimentaires actuels,mais leurs surfaces cultivées ont largement diminué. Les objectifs de notre étude étaient (i) deconcevoir, avec les acteurs locaux du Plateau Langrois (Bourgogne), des scénarios agronomiques deréintroduction de légumineuses, (ii) d'évaluer ex ante ces scénarios, et (iii) de discuter les conditions deleur mise en œuvre sur ce territoire. Les acteurs ayant participé étaient issus du monde agricole(agriculteurs, conseillers techniques), de l’environnement (syndicat d’eau, Parc National) et de larecherche.La première étape a consisté à décrire et évaluer les itinéraires techniques actuels et prospectifs à partirde données statistiques et de résultats d’enquêtes individuelles. Dans un second temps unereprésentation du territoire actuel (assolement de cultures et de façons de cultiver) a été construite avecles acteurs et nous a servi de point de référence. Les acteurs ont ensuite exprimé leurs attendus pource territoire. Parmi les huit pistes de scénarios ayant émergé, quatre ont fait l’objet d’une simulationavec l'outil Coclick'eau, qui optimise, pour chacun de ces scénarios, un assolement alternatif et calculeses performances agronomiques, socio-économiques et environnementales. Finalement, ces résultatsont été présentés et discutés avec les acteurs

Pulses for Sustainability: Breaking Agriculture and Food Sectors Out of Lock-In

Crop diversification can improve the sustainability of Western agriculture. In particular, pulses are crops that can help both agriculture and the food industry become more ecological, as they reduce greenhouse gas emissions and help reduce animal-based consumption. Today, however, the development of these crops in Europe has been hindered due to lock-in, since major crops have been co-developed to a greater extent in farming and food systems. After briefly reviewing the major mechanisms that lead to this lock-in, this article adopts a co-evolution framework to address the interconnected transition of agriculture and food systems. We explore how current societal trends in the agrifood system offer new opportunities for pulses, and how simultaneous changes both in production and consumption can facilitate this dual transition. Drawing on insights from the literature and interviews with stakeholders in France—taken here as examples—we argue that to develop pulses, strong support is required from public institutions to coordinate and guide the multiple actors involved in the same direction

Influence des fortes températures pendant la floraison

National audienc

Effet de nutritions azotées suboptimales sur le fonctionnement d'un peuplement de blé : Analyse et modélisation

5 graph. Résumés des exposés*INRA, Centre de Versailles-Grignon (FRA) Diffusion du document : INRA, Centre de Versailles-Grignon (FRA)National audienc

Le nombre de graines par tige

National audienc

Effet des différents stress sur le fonctionnement : influence des stress abiotiques. Influence des fortes températures pendant la floraison

National audienc

Analyse et modélisation de l'élaboration du rendement et de la qualité des grains pour la conduite des cultures

*UMR d'Agronomie, Bibliothèque, 78850 Thiverval-Grignon Diffusion du document : UMR d'Agronomie, Bibliothèque, 78850 Thiverval-Grigno