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Yam (Dioscorea spp.) is a tuber crop grown for food security, income generation, and traditional medicine. This crop has a high cultural value for some of the groups growing it. Most of the production comes from West Africa where the increased demand has been covered by enlarging cultivated surfaces while the mean yield remained around 10 t tuber ha−1. In West Africa, yam is traditionally cultivated without input as the first crop after a long-term fallow as it is considered to require a high soil fertility. African soils, however, are being more and more degraded. The aims of this review were to show the importance of soil fertility for yam, discuss barriers that might limit the adoption of integrated soil fertility management (ISFM) in yam-based systems in West Africa, present the concept of innovation platforms (IPs) as a tool to foster collaboration between actors for designing innovations in yam-based systems and provide recommendations for future research. This review shows that the development of sustainable, feasible, and acceptable soil management innovations for yam requires research to be conducted in interdisciplinary teams including natural and social sciences and in a transdisciplinary manner involving relevant actors from the problem definition, to the co-design of soil management innovations, the evaluation of research results, their communication and their implementation. Finally, this research should be conducted in diverse biophysical and socio-economic settings to develop generic rules on soil/plant relationships in yam as affected by soil management and on how to adjust the innovation supply to specific contexts.

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The Participatory Market Chain Approach (PMCA) was developed originally to foster pro-poor innovation in potato market chains in the Andean highlands of South America. After promising results in Peru and Bolivia, two questions emerged: (1) Could the PMCA be successfully used to stimulate innovation outside the Andes and in other commodity chains? (2) What would it take to successfully introduce and apply the PMCA in a new setting? The first test application of the approach outside of the Andes was in Uganda. This paper outlines how the PMCA was developed in the Andes and its main features. It then describes the strategies used to introduce the PMCA to Uganda and some of the results to date. The Ugandan experience indicates that the PMCA can, in fact, stimulate technological and institutional innovation in locally relevant agricultural commodity chains in Africa. Since the PMCA requires researchers and development professionals to work in new ways with diverse stakeholders, including not only small farmers but also market agents and policy makers, its successful introduction requires an intensive capacity-development process that fosters the development of social networks, changes in attitudes, and the acquisition of social as well as technical knowledge and skills.

Yam (Dioscorea sp.) is an understudied tuber crop despite its importance for food security, income generation, culture, and health in West Africa. Traditional yam cropping practices in West Africa deliver low yields and lead to environmental degradation. In the context of a ‘research for development’ project, we developed and implemented a participatory and transdisciplinary research approach as a means to derive more sustainable yam production practices. We identified and studied different soil and plant management technologies adapted to varying biophysical and socio-economic contexts. For this purpose, we established innovation platforms (IPs) in four yam growing regions of West Africa, to validate the new technologies and to promote their adoption. These co-developed technologies were set up and tested first in researcher-managed plots before doing the same in farmer-managed plots. The new technologies resulted in a significant increase in yam productivity compared to conventional practices. The results discussed in the IPs gained interest from regional stakeholders and were shared through the media at local and national levels. Overall, this development-focused research approach showcases the relevance of purposeful stakeholder involvement to improve agricultural research outcomes.