Drought and low nitrogen impact on finger millet yield and grain nutrition

Dry and nutrient-poor soils pose a significant threat to food and nutritional security. Finger millet ( Eleusine coracana [L.] Gaertn.), a climate-resilient nutraceutical crop, shows promise in such soils. However, reproductive-stage performance of this crop under low-nitrogen and drought conditions has been overlooked relative to that of major cereals. This study evaluated the growth, yield, and grain nutrient-related trait responses of finger millet under control (CNT), low nitrogen (LN), drought stress (DS), and combined LN+DS conditions. Although all stresses during flowering delayed days to maturity, DS had a greater negative impact on yield components, whereas LN significantly affected grain nutrient content. The yield loss was highest under combined stress (55%), followed by DS (30%), and LN (15%). Although the harvest index remained stable under individual stress, it declined by 25% under combined stress. The phosphorus, potassium, calcium, sulfur, and iron content of grain remained unchanged under all stresses. However, nitrogen under DS and copper, zinc, and boron under LN increased significantly. Therefore, the observed increases likely reflect a combination of concentration effects and sustained or improved nutrient uptake and remobilization, rather than seed size reduction alone. Yield components responded in the order DS+LN > DS > LN, while grain nutrient responses were highest under LN and LN+DS and lowest under DS. This study highlights finger millet’s resilience and biofortification potential under LN and DS. Future studies should prioritize elucidating the molecular mechanisms that regulate multi-stress tolerance during the critical growth stage. • Increasing soil dryness and low fertility highlight the need for climate-resilient crops such as finger millet. • The interactive effects of low nitrogen and drought significantly reduced the yield potential. • Grain nutrient profiles remained more stable than yield traits under low nitrogen and drought.