New perennial grains in African smallholder agriculture from a farming systems perspective. A review

Perennial grain crops are gaining increased attention from researchers as one possible solution to agriculture's many sustainability challenges. In the Sub-Saharan African context, perennial varieties of crops such as sorghum, rice, and pigeon pea have potential to provide numerous benefits for smallholder farmers. The introduction and adoption of new crops and practices is however a complex process that needs to be approached from an interdisciplinary and participatory perspective. We here review the small but growing body of knowledge about on-farm adoption and the use of perennial grains around the world, as well as the more extensive literature of farming systems research. We conclude that a farming systems approach offers a fruitful entry point for informing the emerging research agenda around perennial grains in African smallholder agriculture. Yet, a comprehensive understanding of the potentials and challenges of perennial grains also requires cross-scalar analysis capable of looking beyond the farming system. We thus outline five key considerations for developing and studying new perennial grains in smallholder contexts, i.e., (1) smallholder farming systems are complex, diverse, and locally adapted; (2) decision-making is shaped by various resource constraints; (3) farming is often "semi-subsistence" and forms part of broader livelihood strategies, wherein risk is an important factor; (4) gender relations and roles influence many aspects of smallholder farming systems; and (5) analyses of farmers' production systems, decision-making, and livelihood strategies must be embedded within a broader political-economic context. Based on these considerations, we suggest directions and examples of key questions for future research and derive methodological implications for how such research could be approached.