. Executive, . Of, and . .. Proposal,

. Context, . Of, and . .. Proposal,

A. ,

E. Attard, S. Recous, A. Chabbi, C. De-berranger, N. Guillaumaud et al., Soil environmental conditions rather than denitrifier abundance and diversity drive potential denitrification after changes in land-uses, Global Change Biol, vol.17, pp.1975-1989, 2011.
URL : https://hal.archives-ouvertes.fr/hal-01631828

J. F. Salles, X. Le-roux, and F. Poly, Relating phylogenetic and functional diversity among denitrifiers and quantifying their capacity to predict community functioning, Frontiers Microbiol, vol.3, p.209, 2012.
URL : https://hal.archives-ouvertes.fr/hal-02532817

L. Roux, X. Schmid, B. Poly, F. Barnard, R. L. Niklaus et al., Soil environmental conditions and buildup of microbial communities mediate the effect of grassland plant diversity on nitrifying and denitrifying enzyme activities, PLOS One, 2013.

S. Lavorel, J. Storkey, R. D. Bardgett, D. Bello, F. Berg et al., Linking functional traits of plants and other trophic levels for the quantification of ecosystem services, J. Veg. Sci, 2013.

A. ,

. Anr-gui, , 2013.

D. Tilman, Forecasting agriculturally driven global environmental change, Science, vol.292, pp.281-284, 2001.

R. Hajjar, D. I. Jarvis, and B. Gemmill-herren, The utility of crop genetic diversity in maintaining ecosystem services, Agric. Ecosyst. Environ, vol.123, pp.261-270, 2008.

L. Carvalheiro, Natural and within-farmland biodiversity enhances crop productivity, Ecol. Lett, vol.14, pp.251-259, 2011.

M. Loreau, Linking biodiversity and ecosystems: towards a unifying ecological theory, Philos. Trans. R. Soc. B -Biol. Sci, vol.365, pp.49-60, 2010.

D. Tilman, P. Reich, and J. Knops, Biodiversity and ecosystem stability in a decade-long grassland experiment, Nature, vol.441, pp.629-632, 2006.

C. Roscher, The role of biodiversity for element cycling and trophic interactions: an experimental approach in a grassland community, Basic Appl. Ecol, vol.5, pp.107-121, 2004.

C. Scherber, Bottom-up effects of plant diversity on multitrophic interactions in a biodiversity experiment, Nature, vol.468, pp.553-556, 2010.

R. Bommarco, D. Kleijn, and S. G. Potts, Ecological intensification: harnessing ecosystem services for food security, Trends Ecol. Evol, vol.28, pp.230-238

M. Pitrat, R. Reau, B. Sauphanor, I. Savini, T. Volay et al., Quelles voies pour réduire l'usage des pesticides ? (INRA, 2010)

S. L. Phillips and M. S. Wolfe, Evolutionary plant breeding for low input systems, J. Agric. Sci, vol.143, pp.245-254, 2005.

H. V. Harlan and M. L. Martini, A composite hybrid mixture, J. Am. Soc. Agron, vol.21, pp.487-490, 1929.

C. A. Suneson, An Evolutionary Plant Breeding Method, Agron. J, vol.48, pp.188-191, 1956.

E. Lammerts-van-bueren, The need to breed crop varieties suitable for organic farming, using wheat, tomato and broccoli as examples: A review. Njas -Wagening, J. Life Sci, 2010.

C. Chateil, Crop genetic diversity benefits farmland biodiversity in cultivated fields, Agric. Ecosyst. Environ. In press, 2013.
URL : https://hal.archives-ouvertes.fr/hal-00816466

G. M. Crutsinger, Plant Genotypic Diversity Predicts Community Structure and Governs an Ecosystem Process, Science, vol.313, pp.966-968, 2006.

, Projet WHEATAMIX DOCUMENT SCIENTIFIQUE

C. Lecarpentier, I. Goldringer, B. Andrieu, and J. Enjalbert, Coupling genetic and eco-physiologic models to simulate temporal evolution of cultivar mixtures and composite populations, 2013.

M. R. Finckh, Cereal variety and species mixtures in practice with emphasis on disease resistance, Agronomie, vol.20, pp.813-837, 2000.
URL : https://hal.archives-ouvertes.fr/hal-00886081

C. C. Mundt, Use of multiline cultivars and cultivar mixtures for disease management, Annu. Rev. Phytopathol, vol.40, pp.381-410, 2002.

B. Ney, Crop architecture and crop tolerance to fungal diseases and insect herbivory. Mechanisms to limit crop losses, Eur. J. Plant Pathol, vol.135, pp.561-580, 2013.
URL : https://hal.archives-ouvertes.fr/hal-01000864

V. Ninkovic, S. Al-abassi, E. Ahmed, R. Glinwood, and J. Pettersson, Effect of within-species plant genotype mixing on habitat preference of a polyphagous insect predator, Oecologia, vol.166, pp.391-400, 2010.

M. Chelle, Phylloclimate or the climate perceived by individual plant organs: What is it? How to model it? What for?, New Phytol, vol.166, pp.781-790, 2005.
URL : https://hal.archives-ouvertes.fr/hal-02674939

C. Fournier and B. Andrieu, ADEL-maize: an L-system based model for the integration of growth processes fom the organ to the canopy. Application to regulation of morphogenesis by light availability, Agronomie, vol.19, pp.313-327, 1999.

S. Macfadyen, P. G. Craze, A. Polaszek, K. Van-achterberg, and J. Memmott, Parasitoid diversity reduces the variability in pest control services across time on farms, Proc. Biol. Sci, vol.278, pp.3387-3394, 2011.

M. Fenzi, C. Bonneuil, and P. Gouyon, Pour Une Socio-Anthr. L'environnement (S. Poirot-Delpech et L. Raineau, sous presse, 2011.

R. Whitlock, J. P. Grime, R. Booth, and T. Burke, The role of genotypic diversity in determining grassland community structure under constant environmental conditions, J. Ecol, vol.95, pp.895-907, 2007.

S. C. Cook-patton, S. H. Mcart, A. L. Parachnowitsch, J. S. Thaler, and A. A. Agrawal, A direct comparison of the consequences of plant genotypic and species diversity on communities and ecosystem function, Ecology, vol.92, pp.915-923, 2011.

L. Prost, M. Cerf, and M. H. Jeuffroy, Lack of consideration for end-users during the design of agronomic models : a review, Agron. Sustain. Dev, vol.32, pp.581-594
URL : https://hal.archives-ouvertes.fr/hal-00930534

M. Cerf, M. Jeuffroy, L. Prost, and J. Meynard, Participatory design of agricultural decision support tools: taking account of the use situations, Agron. Sustain. Dev, vol.32, pp.899-910, 2012.
URL : https://hal.archives-ouvertes.fr/hal-00930567

R. Reau, L. A. Monnot, A. Schaub, N. Munier-jolain, I. Pambou et al., Les ateliers de conception de systèmes de culture pour construire, évaluer et identifier des prototypes prometteurs, Innov. Agron, vol.5, p.33, 2012.

C. M. Donald, The breeding of crop ideotypes, Euphytica, vol.17, pp.385-403, 1968.

D. C. Rasmusson, An Evaluation of Ideotype Breeding, Crop Sci, vol.27, pp.1140-1146, 1987.

M. Armstrong, A more general theory of commodity bundling, J. Econ. Theory, vol.148, pp.448-472, 2013.

M. E. Porter, Choix stratégiques et concurrence: techniques d'analyse des secteurs et de la concurrence dans l'industrie, 1982.

G. P. Cachon and M. A. Lariviere, Contracting to Assure Supply: How to Share Demand Forecasts in a Supply Chain, Manag. Sci, vol.47, pp.629-646, 2001.

S. Gavirneni, Benefits of co-operation in a production distribution environment, Eur. J. Oper. Res, vol.130, pp.612-622, 2001.

R. Cowan and P. Gunby, Sprayed to Death: Path Dependence, Lock-In and Pest Control Strategies, Econ. J, vol.106, pp.521-563, 1996.

G. Vanloqueren and P. V. Baret, How agricultural research systems shape a technological regime that develops genetic engineering but locks out agroecological innovations, Res. Policy, vol.38, pp.971-983, 2009.

D. Olivier, G. Schutter, and . Vanloqueren, The New Green Revolution: How Twenty-First-Century Science Can Feed the World. Progress. Radio Netw

S. Paillard, B. Dorin, and T. Le, Food Security by 2050: Insights from the Agrimonde Project, 2013.
URL : https://hal.archives-ouvertes.fr/hal-00807051

S. T. Lovell, Integrating agroecology and landscape multifunctionality in Vermont: An evolving framework to evaluate the design of agroecosystems, Agric. Syst, vol.103, pp.327-341, 2010.

M. Loreau, Ecology -Biodiversity and ecosystem functioning: Current knowledge and future challenges, Science, vol.294, pp.804-808, 2001.

A. ,

B. Chevassus and M. Griffon, La nouvelle modernité : une agriculture productive à haute valeur écologique, Demeter -Econ. Strat. Agric, pp.7-48, 2008.

J. Meynard, Freins et leviers à la diversifi cation des cultures, 2013.

N. Brisson, Why are wheat yields stagnating in Europe? A comprehensive data analysis for France, Field Crops Res, 2010.
URL : https://hal.archives-ouvertes.fr/hal-00964258

D. Vallavieille-pope and C. , Management of disease resistance diversity of cultivars of a species in single fields: controlling epidemics, C. R. Biol, vol.327, pp.611-620, 2004.
URL : https://hal.archives-ouvertes.fr/hal-02681753

L. P. Kiaer, I. M. Skovgaard, and H. Østergård, Grain yield increase in cereal variety mixtures: A meta-analysis of field trials, Field Crops Res, vol.114, pp.361-373, 2009.

K. Murphy, D. Lammer, S. Lyon, B. Carter, and S. Jones, Breeding for organic and low-input farming systems: An evolutionary-participatory breeding method for inbred cereal grains, Renew. Agric. Food Syst, vol.20, pp.48-55, 2005.

M. S. Wolfe, Developments in breeding cereals for organic agriculture, Euphytica, vol.163, pp.323-346, 2008.
URL : https://hal.archives-ouvertes.fr/hal-02668092

C. C. Mundt, Performance of wheat cultivars and cultivar mixtures in the presence of Cephalosporium stripe, Crop Prot, vol.21, pp.93-99, 2002.

T. Bukovinszky, F. Van-veen, Y. Jongema, and M. Dicke, Direct and indirect effects of resource quality on food web structure, Science, vol.319, pp.804-807, 2008.

T. Whitham, A framework for community and ecosystem genetics: from genes to ecosystems, Nat. Rev. Genet, vol.7, pp.510-523, 2006.

G. Crutsinger, Plant genotypic diversity predicts community structure and governs an ecosystem process, Science, vol.313, pp.966-968, 2006.

S. Gianinazzi, Agroecology: the key role of arbuscular mycorrhizas in ecosystem services, Mycorrhiza, vol.20, pp.519-530, 2010.
URL : https://hal.archives-ouvertes.fr/hal-02663830

J. Schweitzer, Plant-soil-microorganism interactions: Heritable relationship between plant genotype and associated soil microorganisms, Ecology, vol.89, pp.773-781, 2008.

E. Kiers, Ecology -Agriculture at a crossroads, Science, vol.320, pp.320-321, 2008.

H. Ostergard, Time for a shift in crop production: embracing complexity through diversity at all levels, J. Sci. Food Agric, vol.89, pp.1439-1445, 2009.

A. M. Manschadi, J. T. Christopher, G. L. Hammer, and P. Devoil, Experimental and modelling studies of drought-adaptive root architectural traits in wheat, Triticum aestivum L.). Plant Biosyst. -Int. J. Deal. Asp. Plant Biol, vol.144, pp.458-462, 2010.

A. M. Manschadi, G. L. Hammer, J. T. Christopher, and P. Devoil, Genotypic variation in seedling root architectural traits and implications for drought adaptation in wheat (Triticum aestivum L.), Plant Soil, vol.303, pp.115-129, 2008.

A. G. Bengough, Gel observation chamber for rapid screening of root traits in cereal seedlings, Plant Soil, vol.262, pp.63-70, 2004.

V. Maire, N. Gross, L. Da-silveira-pontes, C. Picon-cochard, and J. Soussana, Trade-off between root nitrogen acquisition and shoot nitrogen utilization across 13 co-occurring pasture grass species, Funct. Ecol, vol.23, pp.668-679, 2009.

J. H. Cornelissen, A handbook of protocols for standardised and easy measurement of plant functional traits worldwide, Aust. J. Bot, vol.51, pp.335-380, 2003.

I. Jonckheere, Review of methods for in situ leaf area index determination: Part I. Theories, sensors and hemispherical photography, Agric. For. Meteorol, vol.121, pp.19-35, 2004.

T. Dornbusch and B. Andrieu, Lamina2Shape-An image processing tool for an explicit description of lamina shape tested on winter wheat (Triticum aestivum L.), Comput. Electron. Agric, vol.70, pp.217-224, 2010.
URL : https://hal.archives-ouvertes.fr/hal-01192138

O. Tackenberg, A New Method for Non-destructive Measurement of Biomass, Growth Rates, Vertical Biomass Distribution and Dry Matter Content Based on Digital Image Analysis, Ann. Bot, vol.99, pp.777-783, 2007.

A. Gallais, Modèle pour l'analyse des relations d'associations binaires, 1970.

R. W. Allard and J. Adams, Population Studies in Predominantly Self-Pollinating Species. XIII. Intergenotypic Competition and Population Structure in Barley and Wheat, Am. Nat, vol.103, pp.621-645, 1969.

M. R. Finckh and C. C. Mundt, Plant competition and disease in genetically diverse wheat populations, Oecologia, vol.91, pp.82-92, 1992.

J. Bertheloot, P. Cournède, and B. Andrieu, NEMA, a functional-structural model of nitrogen economy within wheat culms after flowering. I. Model description, Ann. Bot, vol.108, pp.1085-1096, 2011.
URL : https://hal.archives-ouvertes.fr/hal-01019789

A. ,

J. Bertheloot, Q. Wu, P. Cournède, and B. Andrieu, NEMA, a functional-structural model of nitrogen economy within wheat culms after flowering. II. Evaluation and sensitivity analysis, Ann. Bot, vol.108, pp.1097-1109, 2011.
URL : https://hal.archives-ouvertes.fr/hal-01019789

C. Fournier, B. Andrieu, S. Ljutovac, and . Saint-jean, S. in Plant Growth Model. Appl, pp.54-63, 2003.

J. B. Evers, An architectural model of spring wheat: Evaluation of the effects of population density and shading on model parameterization and performance, Ecol. Model, vol.200, pp.308-320, 2007.
URL : https://hal.archives-ouvertes.fr/hal-01191976

J. Lata, Grass populations control nitrification in savanna soils, Funct. Ecol, vol.18, pp.605-611, 2004.
URL : https://hal.archives-ouvertes.fr/bioemco-00139318

H. Reynolds, A. Packer, J. Bever, and K. Clay, Grassroots ecology: Plant-microbe-soil interactions as drivers of plant community structure and dynamics, Ecology, vol.84, pp.2281-2291, 2003.

T. M. Robson, S. Lavorel, J. Clement, and X. L. Roux, Neglect of mowing and manuring leads to slower nitrogen cycling in subalpine grasslands, Soil Biol. Biochem, vol.39, pp.930-941, 2007.
URL : https://hal.archives-ouvertes.fr/hal-02663361

A. K. Patra, EFFECTS OF GRAZING ON MICROBIAL FUNCTIONAL GROUPS INVOLVED IN SOIL N DYNAMICS. Ecol. Monogr, vol.75, pp.65-80, 2005.

X. Le-roux, Effects of aboveground grazing on coupling among nitrifier activity, abundance and community structure, Isme J, vol.2, pp.221-232, 2008.
URL : https://hal.archives-ouvertes.fr/halsde-00345209

S. Henry, D. Bru, B. Stres, S. Hallet, and L. Philippot, Quantitative detection of the nosZ gene, encoding nitrous oxide reductase, and comparison of the abundances of 16S rRNA, narG, nirK, and nosZ genes in soils, Appl. Environ. Microbiol, vol.72, pp.5181-5189, 2006.
URL : https://hal.archives-ouvertes.fr/hal-02668482

S. Henry, Quantification of denitrifying bacteria in soils by nirK gene targeted real-time PCR, J. Microbiol. Methods, vol.59, pp.327-335, 2004.

C. Gigot, Potentialite? des associations de variete? pour limiter la progression e?ide?ique de la septoriose du ble : role des me?anismes de dispersion des spores par la pluie dans un couvert ve?etal hete?oge?e, 2013.

J. M. Knops, Effects of plant species richness on invasion dynamics, disease outbreaks, insect abundances and diversity, Ecol. Lett, vol.2, pp.286-293, 1999.

G. Fried, L. R. Norton, and X. Reboud, Environmental and management factors determining weed species composition and diversity in France, Agric. Ecosyst. Environ, vol.128, pp.68-76, 2008.
URL : https://hal.archives-ouvertes.fr/hal-02666010

G. Langellotto and R. Denno, Responses of invertebrate natural enemies to complex-structured habitats: a metaanalytical synthesis, Oecologia, vol.139, pp.1-10, 2004.

Ö. Östman, The relative effects of natural enemy abundance and alternative prey abundance on aphid predation rates, Biol. Control, vol.30, pp.281-287, 2004.

N. C. Elliott, Fixed precision sequential sampling plans for the greenbug and bird cherry-oat aphid (Homoptera : Aphididae) in winter wheat, J. Econ. Entomol, vol.96, pp.1585-1593, 2003.

J. Six, H. Bossuyt, S. Degryze, and K. Denef, A history of research on the link between (micro)aggregates, soil biota, and soil organic matter dynamics, Soil Tillage Res, vol.79, pp.7-31, 2004.

R. Bardgett, The biology of soil, a community and ecosystem approach, 2005.

S. Scheu, Effects of earthworms on plant growth: patterns and perspectives, Pedobiologia, vol.47, pp.846-856, 2003.

J. M. Anderson and J. S. Ingram, Tropical soil biology and fertility: a handbook of methods, 1993.

M. W. Cadotte, J. Cavender-bares, D. Tilman, and T. H. Oakley, Using Phylogenetic, Functional and Trait Diversity to Understand Patterns of Plant Community Productivity, Plos One, vol.4, p.5695, 2009.

L. Roux, X. Schmid, B. Poly, F. Barnard, R. L. Niklaus et al., Soil environmental conditions and buildup of microbial communities mediate the effect of grassland plant diversity on nitrifying and denitrifying enzyme activities, 2013.

S. Lavorel, J. Storkey, R. D. Bardgett, D. Bello, F. Berg et al., Linking functional traits of plants and other trophic levels for the quantification of ecosystem services, J Veg Sci in press, 2013.

D. Sunding, D. Zilberman, and . Handb, , vol.1, pp.207-261, 2001.