Shared seeds for managing diseases: A comparative study of rice fields in Yuanyang (China)[Des semences en commun pour gérer les maladies]

Through the study of a rare traditional agrosystem, namely rice fields in Yuanyang, China, this article shows that more sustainable farming based on wide crop biodiversity can be practised on agricultural land and allow for pesticide-free disease control. A qualitative and quantitative study conducted in nine villages reveals how seeds are jointly managed in a sociotechnical system involving non-commercial seeds and polycentric selection. To function, the system requires free access to seeds and the absence of conformist pressure as regards varietal choices. We demonstrate that such joint management is viable, but also fragile when confronted with the dominant regime of commercial seeds and polarised selection.