Assessing CMIP6-based future climate impacts on pearl millet yield under climate-smart management across Senegal's agroecological zones using the DSSAT-CERES-millet model

Climate change threatens pearl millet production in West Africa's drylands, requiring robust, evidence-based adaptation options for smallholders. This study assesses mid-century (2040–2069) climate impacts on pearl millet yields under climate-smart management across four agroecological zones (Old Peanut Basin, New Peanut Basin, Eastern and Upper Casamance, and Sylvopastoralism Zone) in Senegal using the DSSAT CERES-Millet model driven by six CMIP6 GCMs under SSP2–4.5 and SSP5–8.5, relative to a 1985–2014 baseline. Three management intervention strategies were evaluated: improved dual-purpose and local varieties, optimized plant density (25,000 vs 12,500 hills ha −1 ), and organo-mineral micro-dosing fertilizer strategies. Simulations projected declines up to 25% in precipitation, shortened growing seasons, and temperature increases of 1.4–3.4 °C, leading to yield reductions up to about 30% without adaptation options. Organo-mineral fertilizer strategies (1250–2500 kg ha −1 manure combined with mineral fertilizer) reduced yield sensitivity to climate change by 12–21% under SSP5–8.5 relative to mineral fertilizer alone, while higher planting density lowered climate-related yield losses by 7–15%. Dual-purpose varieties increased yields by 6–17% under the current climate but showed greater climate sensitivity, with declines of 6–27% under SSP5–8.5. The Sylvopastoral zone emerged as the most vulnerable, whereas Old and New Peanut Basins showed more moderate yield declines. These results demonstrate that microdosing fertilizer strategies, optimized plant density, and context-specific variety choice can enhance millet yield stability under climate change and provide actionable guidance for climate-smart agricultural planning in Senegal's drylands and similar Sahelian systems.