Indigenous farming practices increase millet yields in Senegal, West Africa
Soil degradation is a major constraint to food security in many parts of sub-Saharan Africa. We examined the effect of indigenous (the traditional use of rotating fallow-based systems (toss) for livestock herding and soil enrichment) and non-indigenous farming patterns (the use of fertilizer input or no-inputs (non-toss)) on millet yields and soil characteristics in six villages in west-central Senegal. Soil samples were collected in 60 fields in six villages at 0–10 cm depth in 5 random locations in each field. Total yield was measured as head weight per m2 and head weight per plant. The use of toss systems and hybrid farming (toss + fertilizer input) provided higher millet yields than conventional and low-input systems, and the effects of chemical fertilizer were modest in the small amounts applied by the farmers (7 kg/ha of 15–10-10 N-P-K). Soil carbon and pH and the number of trees were the best predictors of millet yield, but the overall predictive power was modest (R2 < 0.34). This research sheds new light on the evolving role of local techniques and knowledge in the struggle to maintain agricultural productivity, as Sahelian communities confront soil fertility depletion and food insecurity.