Co-designing crop diversification strategies from plot to sociotechnical system to manage root knot nematodes in Mediterranean market gardening systems

This is my presentation at the Cropdiversification Conference Session1 "Co-designing crop diversification: which actors to include beyond the farm?".

ABSTRACT

Co-designing crop diversification strategies from plot to sociotechnical system to manage root-knot nematodes in Mediterranean market gardening systems

Yann Boulestreau^∗±1,3, Marion Casagrande ^1,2, Mireille Navarrete ¹

¹ INRA UR767, Ecodéveloppement, 228 route de l’aérodrome, 84914 Avignon cedex 09, France

² ITAB, 525 route de Gotheron 26320 Saint Marcel les Valence, France

³ ADEME, 20 Avenue du Grésillé, 49000 Angers, France

∗Speaker

± Corresponding author: yann.boulestreau@inra.fr

1 Introduction

Root-knot nematodes (RKN) are causing major yield losses in Mediterranean sheltered market gardening systems on the dominant crops (e.g. tomatoes, melon, lettuce). Climate change and crop specialization are the main causes of increased RKN damages. With the ban of most synthetic nematicides due to their toxicity, no unique and simple technique to control RKN exists. Crop diversification has been identified as one of the main alternatives. Crop diversification consists in introducing in crop successions non-host, trap or allelopathic crops for commercial and non-commercial purposes. However, scientific literature (Magrini et al., 2016; Meynard et al., 2018) has shown that sociotechnical lock-in hinders crop diversification, calling for simultaneous and organized actions of multiple actors to unlock crop diversification. This communication shows a methodology to codesign such collective strategies to favor crop diversification, from plot to sociotechnical system. The design of strategies is based on previous analysis of the sociotechnical lock-in and on previous exploration of innovative strategies already implemented in other contexts. This communication shows how we applied this methodology in “Rhône-Durance-Vaucluse” territory, South East France, on sheltered market gardening systems.

2 Materials and Methods

First, we analysed the sociotechnical system (STS) on “Rhône-Durance-Vaucluse” territory responsible for the present soil pest and disease management implemented by market gardeners. We identified the actors with a strong influence on RKN management based on literature and on snowball sampling procedure (Salembier et al., 2016). To understand the main impediments to crop diversification and the sociotechnical lock-in around crop specialization, we interviewed 33 actors including 16 organic and conventional farmers, representatives of agricultural advisory services, wholesalers, input-suppliers and the head of the wholesale marketplace. We also reviewed white and grey literature, and led participatory observation of key meetings involving the STS actors. Then, we characterized existing innovative strategies in other contexts that could unlock crop diversification in ours, based on stakeholders interviews, literature review and key meeting observation.

Finally, we organized a collective design process of innovative strategies to unlock crop diversification with key STS actors. KCP methodology (Le Masson et al., 2009) was used as a 3-phase methodological framework for this collective design process. The Knowledge-phase consisted of sharing knowledge with participants about the RKN management techniques, the impediments for crop diversification, the lock-in of the STS and some existing innovative strategies in other contexts that could help them think “out-of-the-box” (e.g. potato farmers without land renting new fields from cereal farmers every year). A dynamic presentation of management technique posters by technical experts and simulations of the sociotechnical system evolution based on a serious game were used to share this knowledge. The Concept-phase was an oriented exploration of strategy prototypes with the same “serious game” (Fig.1.). The Project-phase will occur later in our research. K-phase and C-phase were started during two workshops with two different groups of farmers: (i) a mix of six organic and conventional farmers selling their products to various whole salers, (ii) a group of six organic farmers selling to the same wholesaler and the wholesaler’s crop planning manager.

3 Results

Besides market gardeners, the key stakeholders of the STS were the vegetable wholesalers and retailers, consumers, input-suppliers (seedlings, seeds), breeders, extension services (advisers, applied research stations), farmer cooperatives and agri-food chain coordinators. The main impediments identified for crop diversification were, from plot to agri-food chain level: unsuitable soils (e.g. too many stones for vegetable root crops), investment in tunnel or greenhouse limiting the species diversity that could be produced and a lack of local outlet for minor crops. The market-gardening sector was locked around the requirement to produce large volumes of a single product at low cost, especially for conventional production. Then, to satisfy brokers, middle size market gardeners needed to specialize in very few products. To unlock the system, innovative strategies were explored: coordination between farmers (e.g. exchange of fields between a RKN host plant producer and a non-host crop producer to diversify rotations without diversifying outlets) and coordination between farmers and brokers (e.g. the brokers open a new outlet enabling farmers to diversify their crops).

Thanks to the exchange with the STS stakeholders during the workshops, the understanding of the impediments for crop diversification and the lock-in was refined. Strategy prototypes were designed, integrating actions from plot to sociotechnical system. For instance, workshop participants proposed to insert new non-host crops such as spring garlic and artichoke in nematode infected plots in coordination with the brokers’ needs and other existing spring garlic or artichoke producers. Actions at farm level only were also proposed such as moving the shelter structure from a RKN infected plot to another healthy plot.

4 Discussion and Conclusions

To conclude, we engaged market-gardeners and other key STS actors from the “Rhône-Durance-Vaucluse” territory in a common effort to understand and to analyze STS lock-in and explore strategies from farm to STS levels that could unlock crop diversification. Realistic RKN management strategy prototypes adapted to “Rhône-Durance-Vaucluse” sheltered market-gardening systems were designed. Even if we focus on crop diversification in this communication, it needs to be combined with other RKN management techniques (e.g. fresh organic matter supply) to effectively manage RKN populations. The next challenge is now to evaluate how effective these agroecological strategies are to control RKN populations, how they would impact the STS, and to detail how they could be implemented. Another stakeholder workshop is planned in autumn 2019.  

References

Le Masson, P., Hatchuel, A., Weil, B. (Eds.), 2009. Design theory and collective creativity: A theoretical framework to evaluate KCP process.

Magrini, M.-B., Anton, M., Cholez, C., Corre-Hellou, G., Duc, G., Jeuffroy, M.-H. et al, 2016. Why are grain-legumes rarely present in cropping systems despite their environmental and nutritional benefits?: Analyzing lock-in in the French agrifood system. Ecological Economics 126, 152–162. https://doi.org/10.1016/j.ecolecon.2016.03.024.

Meynard, J.-M., Charrier, F., Le Bail, M., Magrini, M.-B., Charlier, A., Messéan, A., 2018. Socio-technical lock-in hinders crop diversification in France. Agron. Sustain. Dev. 38, 54.

Meynard, J.-M., Messéan, A., Charlier, A., Charrier, F., Fares, M.'h., Le Bail, M. et al, 2013. Freins et leviers à la diversification des cultures: Étude au niveau des exploitations agricoles et des filières. OCL 20, D403. https://doi.org/10.1051/ocl/2013007.

Salembier, C., Elverdin, J.H., Meynard, J.-M., 2016. Tracking on-farm innovations to unearth alternatives to the dominant soybean-based system in the Argentinean Pampa. Agron. Sustain. Dev. 36, 1. https://doi.org/10.1007/s13593-015-0343-9.