Tillage-mulch-nutrient interaction effect on N, P and K balance in soil and plant uptake in maize-black gram cropping system in an acid soil of North Bengal

Field experiments were conducted to evaluate tillage-mulch-nutrient (partial replacement of inorganic with organic) interaction through soil conservation techniques in maize-black gram rotation. The nutrient balance was positive for nitrogen (N) and potassium (K), but was negative for phosphorus (P). Larger negative P balances were recorded in all the treatments with vermicompost over sole chemical fertilizer treatments. Net negative balance diminished over years in organic manure treatments, but increased with sole chemical fertilizers, indicating that with the passage of time, P may slowly became available in acid soils of north Bengal.