Influence of Organic Manures and Nitrogen Levels on Soil Health and Nutrient Dynamics in Finger Millet (Eleusine coracana L.)

Aims: To evaluate the effects of different organic manures and nitrogen levels on nutrient uptake, soil available nutrients, and soil organic carbon in finger millet (Eleusine coracana L.) under organic farming conditions. Study Design: Split-plot field experiment. Place and Duration of Study: Organic Farming Research Station, Naganahalli, Mysore, India, during three consecutive Kharif cropping seasons: July 2022–November 2022, July 2023–November 2023 and July 2024–November 2024. Methodology: Seven organic manure treatments—farmyard manure, diancha, biocompost, poultry manure, biodigester liquid, jeevamruta, and control—were evaluated in combination with three nitrogen levels: 100%, 150%, and 200% of the recommended dose. Soil available N, P₂O₅, K₂O, organic carbon content, and nutrient uptake by the crop were measured over three years, and pooled data were analyzed. Results: The pooled analysis of three years revealed that biocompost (O3) recorded the highest nutrient uptake (50.65, 52.48 and 53.82 kg ha⁻¹), available nutrients (329, 354 and 362 kg ha⁻¹) and organic carbon (1.40%), followed by poultry manure (O4). In contrast, control (O7) showed the lowest uptake (27.28, 29.22 and 31.67 kg ha⁻¹), available nutrients (212, 223 and 236 kg ha⁻¹) and organic carbon (1.07%), which was almost similar to the initial status (1.06%). Among nitrogen levels, 200% N (N3) recorded maximum uptake (45.73, 47.19 and 48.39 kg ha⁻¹), available nutrients (302, 325 and 333 kg ha⁻¹) and organic carbon (1.35%), while the minimum was under 100% N (N1). Overall, organic manure application, particularly biocompost, coupled with higher nitrogen levels, enhanced soil fertility and nutrient uptake, though their interaction was non-significant. Conclusion: Application of biocompost or poultry manure with optimal nitrogen enhances soil health, nutrient availability, and crop performance in organic finger millet systems, contributing to sustainable and long-term soil productivity.