Fertilizer prescription for desired target yield of direct seeded rainfed upland rice in north eastern hill region

An experiment was carried out to develop soil test crop response correlation based fertilizer prescription for direct seeded rainfed upland rice in soils of north eastern hill region. Field experiments were conducted with rice (Oryza sativa L.; cv. RC Maniphou 6) as gradient crop and also as test crop in two consecutive kharif seasons of 2010 and 2011, respectively. The fertility gradients were created with respect to nitrogen (N), phosphorus (P) and potassium (K) by applying graded dose of fertilizer. From the soil test values, yield and NPK uptake by the test crop, the basic parameters viz., nutrient requirement, soil efficiency and fertilizer efficiency were computed. Fertilizer adjustment equations were developed for upland rice using the basic data, which showed that N, P and K requirement to produce one quintal of rice grain was 2.75, 0.20 and 3.53 kg, respectively. Based on these equations, fertilizer recommendations were prescribed in the form of a ready reckoner for desired target yield of 30.0 and 40.0 q ha ⁻¹ of direct seeded rice with different combination of NPK under rainfed upland situation. Results of the verification trials proved that soil test based fertilizer prescription for direct seeded rice was economically viable in upland agro-ecosystems of Manipur.