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International audience; In this paper, our objective was to study the consistency of the mineral composition of leaves from Fraxinus excelsior L. according to their provenance and management, i.e. pollarded vs. high stem trees. The leaves were collected in August 2016 on 7 sites spread out in 3 regions of France. The concentrations in Ca, Na, Fe, Mn and Cu of ash tree leaves, exhibited a high variability (coefficient of variation, C.V.>30%), while the concentrations in N, K, Mg, P, and Zn varied in a lesser extent (C.V.

To face the new challenges of dairy farming in North-Western Europe, an innovative dairy system was redesigned to produce milk in a context of climate change while saving scarce resources (water, fossil energy) and contributing to a sustainable agriculture. This system, called OasYs, is based on the diversification of forage resources, the development of grazing, larger use of legumes and on a consistent strategy for the livestock system (Novak et al., 2015). The main research hypothesis is that the increase of diversity allows to conciliate production levels and environmental performance, this way improving system resilience.

L’élevage laitier doit faire face à de nouveaux défis : produire du lait dans un contexte de changement climatique, en économisant les ressources en voie de raréfaction (eau et énergie fossile), tout en contribuant à une agriculture durable. Dans ce cadre, un système laitier innovant basé sur une diversification des ressources fourragères, l’allongement du pâturage, le développement des légumineuses et une stratégie d’élevage adaptée, est mis en place à Lusignan (Poitou-Charentes). Nous faisons l’hypothèse que la résilience du système face aux aléas climatiques passe par une plus grande diversité de ses composantes et de leurs fonctions, cette diversité permettant également de concilier un niveau de production et des performances environnementales élevées. Les prairies temporaires sont au coeur de ce système bioclimatique baptisé OasYs. Elles sont diversifiées à la fois au niveau des espèces et des variétés et de leurs assemblages, mais également au niveau de leurs strates et de leurs modes d’exploitation., Dairy farming has to face new challenges, i.e. to produce milk in a context of climate change while saving scarce resources (water, fossil energy) and contributing to a sustainable agriculture. In this frame, an innovative dairy system, based on the diversification of forage resources, the development of grazing, a larger use of legumes and on a consistent strategy for the livestock system, is implemented in Lusignan (Poitou-Charentes). The main research hypothesis tested is that the resilience of the system to climatic hazards goes through a greater diversity of its components and of their functions, which allows also to conciliate good production levels and high environmental performance. Temporary grasslands are in the heart of this bioclimatic system called OasYs. They are diversified regarding their species, cultivars and their mixtures, but also regarding their three-dimensional space and their management.

Depuis plusieurs décennies, l’évolution de l’agriculture en France est, dans un certain nombre de régions de grande culture et d’élevage marquée fortement par la simplification des assolements accompagnée d’un usage accru des intrants et la standardisation des itinéraires techniques. Le challenge est maintenant de concevoir des agroécosystèmes plus diversifiés dans l’objectif d’une gestion écologique des parcelles cultivées devant se traduire par une amélioration de la productivité et la stabilité des systèmes face à divers aléas et la fourniture de différents services éco-systémiques. Ce projet a exploré l’augmentation de la diversité cultivée au sein de la parcelle via des associations céréale-légumineuse. Il a montré la diversité des services que l’on peut en attendre en agriculture biologique et en agriculture conventionnelle, en système céréalier et en système d’élevage. Ces associations permettent de répondre à la fois à des enjeux de production, de réduction des intrants, de réduction des impacts environnementaux des cultures, de stabilité face à des aléas biotiques et abiotiques. Le coeur du projet a consisté a testé différents leviers d’actions pour aider à l’orientation des performances de ces associations pour différents objectifs. Les atouts et contraintes ’adoption à l’échelle des filières (notamment pour les collecteurs) ont été aussi mis en évidence et quantifiés., We have seen in the last decades in France a great simplification in crop successions in cereal farms and mixed farms with livestock with an increasing use of inputs and a standardization of crop management. The challenge is now to build more diversified agroecosystems through an ecological management of crop areas in order to increase yields and stability and to supply several ecosystemic services. This project has investigated the increase in crop diversity in space within the field through cereal-legume intercropping. Different services may be obtained in organic and conventional farming systems, in cereal and mixed farms with livestock. Intercropping can combine productivity, reduction of inputs, environmental impacts and stability against various biotic and abiotic constraints. Several practices have been tested in order to manage performance of intercrops for different aims. The advantages and constraints for different stakeholders such as collectors have been investigated and quantified.

El objetivo fue comparar el rendimiento de materia seca (RMS) y la calidad de variedades de sorgo de grano y forrajero con o sin nervadura café (bmr), al emplear plantas con concentraciones promedio de 300 g kg-1 de MS. Se estudiaron tres variedades de grano (Solarius, Aralba y Topsilo) y tres forrajeras (Sweet Virginia, Big Kauna y Sucrosorgho). Sweet Virginia and Big Kahuna contienen el gen bmr. El RMS varió de 11.10 t, de Topsilo, a 17.12 tha-1 de Sweet Virginia, relacionada con la altura de planta y con la proporción tallo/planta. Topsilo tuvo mayor número de rebrotes (1.5 m-1). La relación panícula/planta no fue diferente entre variedades. El número de plantas m-1 varió entre variedades pero no afectó el RMS. La concentración de proteína varió de 75.45 g kg-1 MS en Big Kahuna, a 104.3g kg-1 MS en Solarius, y tuvo relación inversa con el RMS, con la altura de la planta y con la relación tallo/planta. Las variedades con mayor concentración de proteína (Solarius, Aralba y Topsilo), fueron las de menor RMS, menor altura y menor relación tallo/planta. El área foliar por planta fue la fuente de variación de la proteína entre las variedades de grano. La digestibilidad varió de 596 g kg-1 MS en Aralba, a 720.4 g kg-1 MS en Sweet Virginia, y estuvo relacionada con la concentración de lignina. Esta última variedad junto con Big Kahuna y Solarius fueron las de mayor digestibilidad. La alta digestibilidad de Solarius (no portador de bmr) se debió a su baja proporción (0.35) tallo/planta. La variedad Sweet[br/] Virginia es una importante opción en la alimentación animal dado a su elevado RMS y digestibilidad. Solarius tuvo bajo RMS, pero es útil cuando se requieren altos consumos de materia seca digestible por animal (vacas lecheras), además de contar con la mayor concentración de proteína., The aim was to compare yield of dry matter (RMS) and quality of grain and foliage sorghum varieties with and without brown midrib (bmr), by using plants with average concentrations of 300 g kg-1 of DM. Three grain (Solarius, Aralba and Topsilo) and three forage (Sweet Virginia, Big Kauna and Sucrosorgho) varieties were studied. Sweet Virginia and Big Kahuna contain bmr gene. RMS varied from 11.10 t, of Topsilo, to 17.12 t ha-1 of Sweet Virginia, related with plant height and stem/plant proportion. Topsilo had greater number of sprouts (1.5 m-1). Relationship panicle/plant was similar between varieties. Number of plants m-1 had variation between varieties but did not affect RMS. Protein concentration was from 75.45 g kg-1 DM in Big Kahuna, up to 104.3 g kg-1 DM in Solarius, and had inverse relationship with RMS, with plant height and with stem/plant ratio. Varieties with greater protein concentration (Solarius, Aralba and Topsilo), showed least RMS, lower height and lower ratio stem/plant. Foliar area per plant was source of protein variation between grain varieties. Digestibility ranged from 596 g kg-1 DM in Aralba, up to 720.4 g kg-1 DM in Sweet Virginia, and was related with lignin concentration. This last variety with Big Kahuna and Solaris were the best in digestibility. The high digestibility from Solarius (not bmr carrier) was because its low stem/plant ratio (0.35). Sweet Virginia variety is an important option in animal food since its high RMS and digestibility. Solarius had low RMS, but is useful for high consumption of digestible dry matter (dairy cows), also has better protein concentration.

Objetivou-se avaliar as características morfo-anatômicas de cinco genótipos de milho normais (F2, Lu16, F271, Lu5 e Lu6) e cinco bm3 (F2bm3, Lu16bm3, F271bm3, Lu5bm3 e Lu6bm3) com inferência à qualidade para silagem cultivados em Druelle-França, em parcelas de 150 m² durante o período de maio a setembro de 2002 (150 dias). Todas as avaliações foram realizadas no entrenó abaixo da espiga principal. O delineamento experimental utilizado foi o inteiramente casualizado com cinco repetições por tratamento. Os genótipos apresentaram diferenças significativas quanto aos aspectos anatômicos, sendo que todos os genótipos bm3 apresentaram menores quantidades de células lignificadas tanto na região medular (1,24) quanto na região do córtex (1,72). Observou-se correlação positiva (r= 0,70) entre a quantidade de células lignificadas da região medular e a porcentagem de região medular. Também houve correlação positiva (r= 0,67) e negativa (r= -0,67), entre a espessura da parede celular com a % de xilema e com a % de floema, respectivamente. Os resultados encontrados estão coerentes aos tipos de linhagens estudadas, pois as linhagens bm3 são caracterizadas por apresentarem menores proporções de lignina quando comparados com genótipos normais., The objective was to evaluate the morphoanatomical characteristics of ten genotypes of corn to silage, five normal (F2, Lu16, F271, LU5 and LU6) and five bm3 (F2bm3, Lu16bm3, F271bm3, Lu5bm3 and Lu6bm3), grown in Druelle-France, in plots of 150 m² during the period from May 2002 to september 2002, totaling a period of 150 days. All evaluations were performed in internode below the primary ear. The experimental design was completely randomized, with five replications per treatment. The genotypes showed significant differences on the anatomical aspects evaluated, and that all bm3 genotypes showed lower amounts of both lignified cells in the medullar region (1.24) as in the cortex (1.72). The statistic analysis pointed positive correlation (r= 0.70) between the amount of lignified cells in the medullar region and the percentage of medullar region. There was also positive correlation (r= 0.67) between the thickness of the cell wall with the xylem % and negative correlation (r= -0.67) between the thickness of cell wall with the phloem %. The results are consistent to the types of strains studied, because the bm3 lines are characterized by smaller proportions of lignin compared to normal genotypes.

Au cours de 4 années d’expérimentation avec des vaches laitières, différents hybrides de maïs choisis pour leur valeur énergétique mesurée sur moutons standards ont été comparés en ensilage de la plante entière. Les hybrides dont la valeur énergétique estimée sur les moutons était la plus élevée permettent des productions de lait standard supérieures de 1 à 2 kg et des reprises de poids pouvant atteindre 300 g de plus par jour. Les écarts de quantités de matière sèche d’ensilage ingérées ont également atteint 1,5 kg à teneur en matière sèche et teneur en grain constantes. Si les mesures faites sur moutons, comme les mesures de solubilités enzymatiques, permettent nettement de distinguer les hybrides à bonne valeur énergétique des hybrides à faible valeur énergétique, elles ne permettent en revanche pas de classer correctement les hybrides au sein de chacun de ces deux groupes. Enfin, aucune des mesures effectuées sur moutons ou in vitro ne permet de prédire la variabilité observée pour l’ingestibilité., Genetic variation in the feeding efficiency of different maize genotypes was evaluated from experiments with dairy cows. The maize genotypes were chosen according to their variable digestibility range, determined in previous experiments with standard sheep. The variations in milk yield observed with dairy cows fed a low, respectively a high, digestible or energizing hybrid were between 1 to 2.0 kg per animal, per day. Moreover, the differences in body weight gain reached up to 300 g per day. Hybrids having similar energy values acted similarly on milk yield, but the intake could be very different when fed to dairy cows, even if no difference in intake was observed in sheep measurements. The 1.5 kg higher silage maize intake of DK265 was mostly converted into a body weight gain, and not in increasing the milk yield, probably because the milk yield potentiel of the animals was soon reached. It appeared that the hybrids which had a low predicted energy value from the sheep measurements also had a lower performance in cows. Dairy cow performances also appeared to concur with the enzymatic solubility values of the whole plant. However, only good hybrids could be distinguish from poor ones, but the variation within good, respectively poor, hybrids could not reliably be investigated with the enzymatic solubility test used. The variation in ingestibility could not be predicted. For maize breeders, the prediction of an hybrid efficiency for use in dairy cow rearing must include digestibility and ingestibility factors. Enzymatic processes could probably be used to avoid drift towards poor feeding values with hybrids bred for a higher stalk strength. The most important challenge for maize breeders will most likely be the determination of a criterium for the intake prediction. The stover digestibility and starch content can be reliably predicted through the use of NIRS (near infra-red reflectance spectroscopy) calibrations. For a stock-breeder, a pertinent choice of a maize hybrid might allow significant concentrates and money saving.

Les dispositifs expérimentaux mis en place permettront d’étudier différentes espèces, organisations spatiales et types de protection vis-à-vis du troupeau, ainsi que plusieurs modes d’exploitation de ces ressources ligneuses. La valeur nutritive des feuilles collectées en été sur 27 espèces ligneuses fait l’objet d’une large évaluation (valeur énergétique et azotée, teneur en fibres et en tanins condensés, digestibilité, dégradabilité théorique de l’azote). Plusieurs espèces présentent un excellent profil pour leur valeur protéique et énergétique : le mûrier blanc et le frêne, mais aussi le tilleul, l’aulne de Corse et un certain nombre de lianes et d’arbustes. D’autres espèces conviendraient également pour alimenter en été, et par le pâturage, des animaux à l’entretien ou aux besoins plus modérés que des animaux en lactation., Can forage systems exploit trees, shrubs, and lianas, particularly during summer grazing? This study discusses the approaches being used at the INRA center of Lusignan to combine agroforestry and dairy livestock farming. Researchers are examining different species, spatial organisation systems, and means of protecting herds, as well as exploring multiple ways of exploiting woody resources. The first results for nutritional quality (i.e., of leaves collected in the summer) show that a great deal of variability exists among the 27 study species. They also highlight the attractiveness of certain tree species, such as the white mulberry (Morus alba), the ash (Fraxinus excelsior), the common linden (Tilia platyphyllos), and the Italian alder (Alnus cordata), as well as of certain shrubs and lianas. Other species could also be used to feed specific types of grazing animals in the summer, namely those on maintenance diets or with more modest needs (i.e., non-lactating animals).