Modern agricultural systems rely on reduced crop genetic diversity, due in particular to the use of homogeneous elite varieties grown in large areas. However, genetic diversity within fields is a ...lever for a more sustainable production, allowing greater stability and resistance to biotic and abiotic stresses. In France, a Participatory Plant Breeding (PPB) project on bread wheat, involving farmers, facilitators and researchers, has led to the development of heterogeneous populations whose within-variety genetic diversity is expected to confer the ability to adapt to farmers’ practices and environments. We studied the stability and local adaptation of ten of these farmers’ populations as well as two commercial varieties in relation to their within-variety genetic diversity. Although no clear evidence of local adaptation was detected, we found that populations’ grain yield and protein content were more stable over space and time respectively than those of commercial varieties. Moreover, the varieties’ stability over time in terms of protein content was positively correlated with within-variety genetic diversity with no significant drawback on protein yield. These results demonstrate the wide adaptive potential of PPB populations, highlighting the importance of seed exchange networks for agrobiodiversity management and use. They emphasize the benefits of genetic diversity for stability over time, which is of great interest to farmers.
Participatory plant breeding (PPB) is based on the decentralization of selection in farmers’ fields and their involvement in decision-making at all steps of the breeding scheme. Despite the evidence ...of its benefits to develop population varieties adapted to diversified and local practices and conditions, such as organic farming, PPB is still not widely used. There is a need to share more broadly how the different programs have overcome scientific, practical, and organizational issues and produced a large number of positive outcomes. Here, we report on a PPB program that started on bread wheat in France in 2006 and has achieved a range of outcomes, from the emergence of new organization among actors, to specific experimental designs and statistical methods developed, and to populations varieties developed and cultivated by farmers. We present the results of a two-year agronomic evaluation of the first population varieties developed within this PPB program compared to two commercial varieties currently grown in organic agriculture. We found that several PPB varieties were of great agronomic interest, combining relatively good performance even under the most favorable conditions of organic agriculture and good robustness, i.e., the ability to maintain productivity under more constraining conditions. The PPB varieties also tended to show a good temporal dynamic stability and appeared promising for the farmers involved.
•Coaxial deep borehole heat exchangers (1500 to 3000 m) were numerically simulated.•Their design was optimized for heating using materials available on the market.•Pressure losses due to friction ...proved to be an essential parameter to consider.•Repurposing an oil and gas well appears both feasible and economically viable.•Larger new boreholes perform better but would not be cost competitive in Quebec.
Heating performance of deep borehole heat exchangers (DBHEs) is heavily impacted by its design and operating flow rate. Here, various designs of coaxial DBHEs were numerically simulated and compared for 1 year of continuous operation in a cold sedimentary basin using the FEFLOW software. Factors affecting performance, including: (1) depth, (2) repurposing an oil and gas (O&G) well or drilling a larger one, (3) repurposing options, (4) inner pipe material, made of either vacuum insulated tubing (VIT) or high-density polyethylene and (5) grout with different thermal conductivity were evaluated. Where an O&G well is available, the most cost-efficient option is repurposing, with the best performance obtained from the deepest and largest diameter wells. While VIT inner pipes performed better in some designs, their performance did not compensate for their cost.
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Dans les années 2000, des agriculteurs désireux de cultiver des blés correspondant à leurs besoins et soucieux d’affirmer leur autonomie vis-à-vis de l’industrie semencière, ont entrepris de relancer ...la sélection paysanne à la ferme. Des collaborations ont été tissées avec des généticiens de l’Inra, et se sont progressivement développées dans le cadre de projets financés. Or les financements de recherche impliquent une formalisation des partenariats, des engagements en termes de résultats académiques et une augmentation significative de la taille des projets. Dans ce nouveau contexte, comment préserver les valeurs d’émancipation paysanne et de justice cognitive sur lesquelles la collaboration paysans-chercheurs s’est originellement construite ? Cet article aborde la façon dont ce défi se pose concrètement aux acteurs de ces projets, et les précautions qu’ils mettent en œuvre pour y faire face.
Dans les années 2000, des agriculteurs désireux de cultiver des blés correspondant à leurs besoins et soucieux d’affirmer leur autonomie vis-à-vis de l’industrie semencière, ont entrepris de relancer ...la sélection paysanne à la ferme. Des collaborations ont été tissées avec des généticiens de l’Inra, et se sont progressivement développées dans le cadre de projets financés. Or les financements de recherche impliquent une formalisation des partenariats, des engagements en termes de résultats académiques et une augmentation significative de la taille des projets. Dans ce nouveau contexte, comment préserver les valeurs d’émancipation paysanne et de justice cognitive sur lesquelles la collaboration paysans-chercheurs s’est originellement construite ? Cet article aborde la façon dont ce défi se pose concrètement aux acteurs de ces projets, et les précautions qu’ils mettent en œuvre pour y faire face.
In the 2000s, a handful of farmers in France undertook to revive a practice fallen into disuse during agricultural modernization, i.e. on-farm plant breeding. Their motives were both to grow wheat varieties meeting their needs and to assert their independence towards the seed industry. Informal collaborations were woven with geneticists from the French institute for agronomic research (INRA), and developed further within the framework of funded projects. The foundations of a “decentralized participatory plant breeding” were then laid, both on a genetic rationale (breeding directly in the environments where the plants are to be grown) and on strong ethical principles (organizing non-hierarchical relations to let farmers question researchers’ assumptions). However, research funding involves a formalization of partnerships, commitments in terms of academic deliverables, and a significant increase in the size of projects. In this new context, how are the objectives of farmers’ empowerment and the values of cognitive justice on which the collaboration between farmers and researchers was originally built to be preserved? This article describes how this issue is actually tackled by the participants in these projects. We focus in particular on the debates raised by the creation of a database, and on the tensions it generates between centralization and decentralization. We also present the challenges raised by the dramatic increase in the number of participants, which risks to reproduce a division of tasks between researchers, farmers, and the people coordinating at a local level.
In Organic Agriculture, cultivation environments and agronomic practices are very diverse. This diversity can be handled with decentralized selection based on the knowledge of farmers and scientists. ...A collaborative work between associations from Réseau Semences Paysannes and the DEAP team from INRA du Moulon set up an innovative breeding approach on farm based on decentralization and participation of farmers. This approach makes it possible to (i) create new population varieties of bread wheat locally adapted (genetic innovation) (ii) set up an organizational scheme based on decentralization and co construction between actors (societal innovation) and (iii) develop experimental designs, create statistical and data management tools which stimulate these genetic and societal innovations.
En Agriculture Biologique, les environnements des cultures et les pratiques agronomiques sont très diversifiés. Cette diversité peut être prise en compte par une sélection décentralisée associant le savoirfaire des agriculteurs et les connaissances scientifiques des chercheurs. Un travail co-construit entre associations et paysans du Réseau Semences Paysannes et l'équipe de recherche DEAP de l'INRA du Moulon a permis d'élaborer une approche innovante de sélection décentralisée et participative à la ferme. Cette approche permet de (i) créer de nouvelles variétés populations de blé tendre adaptées localement (innovation génétique) (ii) mettre en place un mode d'organisation basé sur la co-construction entre acteurs et la décentralisation (innovation organisationnelle) et (iii) développer des dispositifs expérimentaux, créer des outils statistiques et de gestion de données qui favorisent ces innovations génétique et sociétale
The sense of equilibrium aggregates several interacting cues. On vestibular areflexic patients, vision plays a major role. We developed an immersive therapeutic platform, based on 3D opto-kinetic ...stimulation that enables to tune the difficulty of the balance task by managing the type of optic flow and its speed. The balance adjustments are recorded by a force plate, quantified by the length of the center of pressure trajectory and detection of disequilibrium corrections (leans, compensation step). Preliminary analysis shows that (i) patients report a strong immersion feeling in the motion flow, triggering intense motor response to "fight against fall"; (ii) the ANOVA factorial design shows a significant effect of flow speed, session number and gaze anchor impact. In conclusion, this study shows that 3D immersive stimulation removes essential limits of traditional opto-kinetic stimulators (limited 2D motions and remaining fixed background cues). Moreover, the immersive optic flow stimulation is an efficient tool to induce balance adaptive reactions in vestibular patients. Hence, such a platform appears to be a powerful therapeutic tool for training and relearning of balance control processes.
During immersive balance rehabilitation, automatic visual-vestibular compensations occurs to reduce the patients’ visual reliance and improve the equilibrium. This paper describes the use of an ...identification procedure to characterise the relationship between visual stimulation features involved in this adaptive sensory compensation, and the balance improvement. The purpose is to determine the stimulus-response transfer functions (TF) associated to the equilibrium enhancement. Standing vestibular patients were stimulated by visual virtual flows, whose pattern and speed changed throughout successive stimulation sessions. The analysis of the feet centre-of-pressure, disequilibrium, and identified models parameters for one representative vestibular patient, showed that TF parameters evolved related to the gradual balance recovery boosted by the visual-vestibular compensation. This results suggest that identified TF parameters are suitable indicators for measuring the effect of sensory substitution on equilibrium recovery. This first step to model the relationship between the sensory re-weighting flexibility and the adaptation of postural commands is essential for future clinical studies using identification methods for sensorimotor evaluation in individualized vision-based balance rehabilitation
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