Development of Soil Test based Fertilizer Prescription Equation Using Integrated Nutrient Management Approach for Targeted Yield of Maize Crop in a Vertisol of Chhattisgarh Plain, India

Field experiments were conducted at the research farm of Indira Gandhi Krishi Vishwavidyalaya, Raipur (C.G.) during kharif 2021, and kharif 2022. To study the fertilizer requirement and. Yield performance a regression model was performed to evaluate the variation between yield and fertilizer and found that fertilizer N contribute 87% and 88% (R2 value 0.87,0.88). When applied through NPK variation found about 91 % and 90% (R2 value 0.91, 0.90), for recommendation of fertilizer prescription a ready reckoner was prepared based on these equations for a range of soil test values and for yield targets of 50,60 and 70 q ha-1 for maize, it was found that for a soil test value of 200 kg ha-1 of KMnO4 -N the fertilizer N doses required 91 kg ha-1, 133 kg ha-1 and 175 kg ha-1. For a soil test value of 12 kg ha-1 of Olsen-P, the dose of fertilizer P2O5 required for the yield target was 33 kg ha-1,48 kg ha-1 , 63 kg ha-1 respectively. Similarly for a soil test value of 250 kg ha-1 of NH4OAc-K the fertilizer K doses required 54 kg ha-1, 72 kg ha-1, 91 kg ha-1.