Soil test crop response based fertilizer prescriptions under integrated plant nutrient supply for targeted yield of potato (Solanum tuberosum L) in Inceptisols

Field experiment were carried out on potato (Solanum tuberosum L) during rabi 2018-19 to investigate the soil test crop response based fertilizer prescriptions under integrated plant nutrient supply by following Ramamoorthy’s inductive approach of fertility gradients in Inceptisols at the Instructional Farm of Krishi Vigyan Kendra, Raigarh (C.G.). The fertilizer adjustment equations were derived by the All India Coordinated Research Project (AICRP), College of Agriculture, Indira Gandhi Krishi Vishwavidyalaya, Raipur (C.G.). The nutrient requirement (NR), contribution of nutrients from soil (CS), fertilizer (CF) and farm yard manure (CFYM) were computed using the data on soil test values, fertilizer nutrients doses, nutrient uptake and potato yield. The amount of nutrient required (NR) to produce one quintal of tuber production was found to be 0.42 kg N, 0.11 kg P and 0.45 kg K. The per cent contribution from fertilizer (CF) for N, P and K was estimated 31.27,22.06 and 82.93 per cent for potato crop. The per cent contribution from soil (CS) was recorded as 14.39 for N, 48.94 for P and 17.78 for K in case of potato crop. The per cent contribution of organic source (CFYM) for N, P and K were recorded 8.33, 3.50 and 19.60 for potato crop. Based on this information, soil test based fertilizer prescription equations were developed to predict fertilizer recommendation for obtaining specific yield target of potato crop. Ready reckoners chart for fertilizer N, P2O5 and K2O application based on the soil test values for specific yield targets of potato were also prepared which are useful for the soil testing laboratories.