10 research outputs found
Peaâwheat intercrops in low-input conditions combine high economic performances and low environmental impacts
Intensive agriculture ensures high yields but can cause serious environmental damages. The optimal use of soil and atmospheric sources of nitrogen in cerealâlegume mixtures may allow farmers to maintain high production levels and good quality with low external N inputs, and could potentially decrease environmental impacts, particularly through a more efficient energy use. These potential advantages are presented in an overall assessment of cerealâlegume systems, accounting for the agronomic, environmental, energetic, and economic performances. Based on a low-input experimental field network including 16 site-years, we found that yields of peaâwheat intercrops (about 4.5 Mg haâ1 whatever the amount of applied fertiliser) were higher than sole pea and close to conventionally managed wheat yields (5.4 Mg haâ1 on average), the intercrop requiring less than half of the nitrogen fertiliser per ton of grain compared to the sole wheat. The land equivalent ratio and a statistical analysis based on the Price\u27s equation showed that the crop mixture was more efficient than sole crops particularly under unfertilised situations. The estimated amount of energy consumed per ton of harvested grains was two to three times higher with conventionally managed wheat than with peaâwheat mixtures (fertilised or not). The intercrops allowed (i) maintaining wheat grain protein concentration and gross margin compared to wheat sole crop and (ii) increased the contribution of N2 fixation to total N accumulation of pea crop in the mixture compared to pea sole crop. They also led to a reduction of (i) pesticide use compared to sole crops and (ii) soil mineral nitrogen after harvest compared to pea sole crop. Our results demonstrate that peaâwheat intercropping is a promising way to produce cereal grains in an efficient, economically sustainable and environmentally friendly way
Aphanomyces : quand le froid protĂšge le pois
National audienceLa date des semis du pois d'hiver limite fortement les risques de pertes de rendement dus Ă Aphanomyces euteiches. Toutefois, l'inoculum peut se multiplier. Il convient donc de rester vigilant sur l'Ă©volution du potentiel infectieux du so
Agrophysiologie du pois protéagineux - Applications à la production agricole
National audienc
Inhibition of hepatitis B virus DNA replication by imino sugars without the inhibition of the DNA polymerase: therapeutic implications.
Previously we have shown that the imino sugar inhibitor of N-linked glycan processing, N-nonyl-deoxynojirimycin (N-nonyl-DNJ), had antiviral activity in the woodchuck model of chronic hepatitis B virus (HBV) infection. In studying the mechanism of action of this compound, it was discovered that imino sugars could inhibit HBV secretion without inhibiting N-linked glycoprocessing. Although N-nonyl-DNJ is an inhibitor of the endoplasmic reticulum (ER) glucosidase, here it is shown that N-nonyl-DNJ retained antiviral activity at concentrations that had no significant impact on ER glucosidase function. Taken together, these results suggested that N-nonyl-DNJ possessed an antiviral activity attributable to a function other than an impact on glycoprocessing. This hypothesis was confirmed by experiments showing that N-nonyl-deoxygalactojirimycin (N-nonyl-DGJ), an alkyl derivative of galactose with no impact on glycoprocessing, retains anti-HBV activity. The data suggest that N-nonyl-DGJ exerts its antiviral action at a point before viral envelopment and may prevent the proper encapsidation of the HBV pregenomic RNA
Ideotypes of forage pea (pisum sativum) cultivars
Pea (Pisum sativum L.) is one of the most important grain legume crops in temperate regions worldwide. In many countries of Europe, West Asia and North Africa, it is also used in feeding ruminants in the form of fresh forage, forage dry matter, forage meal, silage, haylage and straw. The goals of breeding pea for forage significantly differ from those in breeding pea for grain. A large majority of currently ongoing breeding programmes on forage pea develop cultivars completely or mostly from local or introduced populations of P. sativum L. subsp. sativum var. arvense (L.) Poir. Such cultivars are characterised by long stems with indeterminate growth, long internodes, great number of nodes, large stipules and three pairs of leaflets, purple flowers and low seed yields in comparison to typical feed pea cultivars. They also have prominent winter hardiness, late maturity and large forage losses due to an extremely poor lodging tolerance, being the reason why these cultivars are mostly grown intercropped with cereals. Much of said traits, such as large aboveground biomass resulting from long stems or large leaves are important segments of the ideotypes of a forage pea cultivar. More recent improvements include determinate stem growth and moderately great stem length, in order to reduce withering of at least a whole lower half of leaves on the plant, as well as a leaf proportion in the aboveground biomass higher than 0.50, improved earliness and a forage dry matter proportion of about 0.25, increasing crude protein content and decreasing both neutral and acid detergent fibre and lignin content in forage dry matter. A successful combination of all these desirable traits may result in a forage pea cultivar producing about or slightly more than 10 t haâ1 of forage dry matter and about 2 t haâ1 of forage crude protein, able to easily fit into diverse cropping systems. The latest trends in forage pea cultivars brought forth the first semi-leafless cultivars with excellent standing ability and enhanced seed production, where numerous and large stipules successfully replace the missing leaflets in providing quality forage
Pertes alimentaires dans la filiÚre protéagineuse
Ce numĂ©ro prĂ©sente les travaux conduits dans le cadre de lâanalyse des Pertes agricoles et alimentaires dont une synthĂšse a Ă©tĂ© prĂ©sentĂ©e lors du colloque du 28 novembre 2015 Ă Paris. Avec lâappui de Redlingshofer B.. Experts interrogĂ©s : Million G., Chereau D.National audienceThe French protein crops chain (pea, faba bean and lupins species) developed in the 1990âs basically to supply the requirements of animal feed, has significantly developed a food outlet since the 2000. From an estimation at 370 000 t of these productions presently dedicated to human food (export + national markets), losses are mainly at harvest representing 22 000 t (6% of the production), to which could be added 1000 t of water soluble sugars issued from the liquid fractioning process. From harvest to distribution, several co-products or wastes are processed into feeds and therefore cannot be considered as losses. Combination of genetic and agronomic progress to monitor a crop canopy coadapted with the progress on harvesting equipments represents the major levers identified to reduce losses. The impact weight of these levers of progress will be positively correlated with the increase of area and volumes of the food outlets of these productions. Beyond actions which will bring competitiveness of the crops, as well as higher and more stable yields together with better sanitary status of their seeds are (i) improvement of their nutritional and health value through varieties and cropping management (adapted proteins, fibers, bioactive compounds,âŠ), (ii) new technologies of fractionation or transformation bringing higher digestibility and added value, (iii) consumer information and (iv) stakeholder organization in the chain, likely to amplify volumes and nutritional efficiency of these products for food outlets..La filiĂšre française des protĂ©agineux (espĂšces pois, fĂ©verole et lupins), dĂ©veloppĂ©e dans les annĂ©es 1980 Ă 1990, avait pour premier objectif de rĂ©pondre aux besoins de lâalimentation animale. A partir des annĂ©es 2000, un marchĂ© significatif vers lâalimentation humaine sâest aussi dĂ©veloppĂ©. Sur la base dâune estimation Ă 370 000 t de protĂ©agineux actuellement destinĂ©es Ă lâalimentation humaine (export + marchĂ© intĂ©rieur), les pertes sont surtout situĂ©es Ă la rĂ©colte et reprĂ©senteraient 22 000 t (soit 6% de la production), auxquelles sâajoutent 1000 t de glucides solubles issues du fractionnement par voie liquide. De la rĂ©colte Ă la distribution, de nombreux coproduits ou dĂ©chets sont orientĂ©s vers lâalimentation animale et ne constituent pas des pertes. Un progrĂšs gĂ©nĂ©tique et agronomique portant sur une architecture maĂźtrisĂ©e des couverts vĂ©gĂ©taux, coadaptĂ© au progrĂšs du machinisme de rĂ©colte, constitue le moyen principal pour rĂ©duire les pertes. Le poids dâimpact de ces leviers de progrĂšs sera positivement corrĂ©lĂ© Ă lâaugmentation des surfaces et volumes de ces productions pour un dĂ©bouchĂ© en alimentation humaine. Au-delĂ des actions qui pourront amĂ©liorer la compĂ©titivitĂ© de ces cultures en augmentant et stabilisant les rendements et amĂ©liorant la qualitĂ© sanitaire des graines, (i) une amĂ©lioration gĂ©nĂ©tique et agronomique de la valeur nutritionnelle et santĂ© (protĂ©ines, fibres, composĂ©s bioactifs,âŠadaptĂ©s), (ii) de nouvelles technologies de fractionnement et transformation apportant de la digestibilitĂ© et de la valeur ajoutĂ©e, (iii) une information des consommateurs, (iv) une organisation de filiĂšre, pourront amplifier les volumes et lâefficience nutritionnelle de ces produits dans les dĂ©bouchĂ©s de lâalimentation humaine