Response of maize yield to nitrogen, phosphorus, potassium and sulphur rates on Andosols and Nitisols in Ethiopia

Summary The use of fertilizers in balanced and adequate amounts is a prerequisite for increasing crop productivity production. Unbalanced plant nutrient management continues to be major factor contributing low maize ( Zea mays L.) yields due lack information on the dose–responses macronutrients different soil types Ethiopia. This study was carried out quantify yield response agronomic efficiency varying application rates nitrogen (N), phosphorus (P), potassium (K) sulphur (S) under other nutrients across two Field trials were set up 29 farmers’ fields four districts Oromia Southern Nations, Nationalities Peoples Region (SNNPR) three consecutive cropping seasons (2014–2017). treatments consisted six N, P S each eight K combined with remaining macronutrients, zinc (Zn) boron (B). laid randomised complete blocks design replicates per farm. Using dose–response modelling, optimum P, estimated at 46, 40, 17 10 kg ha −1 Nitisols, nutrients. On Andosols, 184, 20 30 , respectively, but rate could not estimated. predicted maximum obtained lower Andosols (3397–3640 ) than Nitisols (4630–6094 ). Mitscherlich model, percentage deficiencies 1.3–3.3 times more Andosols. Consequently, efficiencies significantly Nitisols. It concluded that 46 N 40 S, 2 Zn 0.5 B recommended area. Although this recommendation may also apply Andosol, further research needed as appears limited by constrains K, B. We recommend shift from blanket fertilizer recommendations site-specific based good understanding variations type agroecology appropriate analyses.