RESUMO
Aim: To develop economically viable integrated fertilizer prescription equation for recommendation of fertilizers in potato on alluvial soils of Eastern India.Methodology: Soil test crop response (STCR) experiments on potato were conducted in alluvial soils of Eastern India during 2016-17 to assess the relationship between yield and availability of plant nutrients for developing fertilizer prescriptions of desired yield targets. The decision on optimum fertilizer doses for varying yield targets were made on the basis of crop nutrient requirement per quintal of potato production, soil efficiency, fertilizer efficiency, and FYM efficiency computed from field experimental data. The optimum fertilizer doses for different yield targets were validated in farmers’ field for economic and environmental benefits as compared to general recommended doses of fertilizers and farmers’ practice. Results: Targeted yield equation for potato for alluvial soil of Eastern India was developed based on soil test values, nutrient requirement and contribution of NPK from soil and fertilizer sources as well as FYM. The prescription based fertilizer application along with FYM increased tuber yield of potato in farmers’ field. Validity of the yield target for 22 and 24 t ha-1 was tested in farmer’s fields and variation in potato yield obtained from targeted yield was 7.6% to 9.8%. Interpretation: Fertilizer prescription equations and ready reckoner developed for potato will be useful in alluvial soils of Eastern India for large scale recommendations and in regions with similar soil and agro-climatic conditions. By following ready reckoner, a farmer can save 61 kg N, 55 kg P2O5 and 44 kg K2O ha-1 over general recommended dose, approximately equal to Rs. 4800/- per hectare.