Co-design of agroecological temperate fruit tree systems in France: the ALTO project

International audienceCrop diversification and agroecological practices preserving biodiversity are a way to foster ecosystem services. The ALTO project is a multi-actor research project based on new fruit production concepts. Three diversified orchards in three sites of Southern France were designed following the same objectives of ecological intensification and production in very low or pesticide-free systems. Agronomic, ecological and organizational aspects were involved in the co-design approach. The first system is a newly planted circular orchard with a pest suppressive design. The second is an orchard, with previous agroecological infrastructures and fruit trees, that has evolved “step by step” into a diversified production area. The third site investigates the effects of spatial arrangement of an agroforestry apple agrosystem on tree architecture and functioning. The design and the evaluation of these experimental systems address three main questions, shared by one, two or all sites: 1) Can crop and non-crop diversification, as well as spatial arrangement, limit fruit damage caused by pests? 2) Can crop design, more specifically agroforestry, impacts abiotic resource sharing between crops? 3) How growing fruit-trees in these diversified systems impact workload and organization? Although this research is in progress and requires multi-year data, the first results provide feedback on the effectiveness of pest suppressive strategies (trap plants and low-susceptibility cultivars, barrier effects, flower strips and diversified surrounding landscape to favor natural enemies of pests, etc.), as well as on resource sharing for light, and on flowering. Tradeoffs between agronomic, ecological and organizational aspects are also investigated. Besides, the experimental prototypes are likely to evolve with time integrating further exchanges with stakeholders and lessons from on-going management. Multicriteria evaluation of these experimented multi-production prototypes is still in progress but the present analysis opens avenues for agroecological design in perennial crops