Establishing Fertilization Recommendation Index Based On Fertilizer Rate Experiments

Recently, numerous field experiments are condueted in national soil testing and fertilization recommendation project, however, how to use these experimental data to establish fertilization recommendation index is urgently needed. Taking the spring maize"fertilizer rate"experiments in Jilin Province as an example, the process of establishing fertilization recommendation index was investigated and diseussed. Soil Olsen-P and NH4OAc-K were classified as low(<75% relative yield), medium(75%-90% relative yield), high(90%-95% relative yield) and very high(>95%relative yield) based on the relative yields. Fertilizer recommended rates were simulated by the models of one-factor for each"fertilizer rate"field experiment. The results indieate that phosphorus fertilizer rates (P2O5) are 83 kg/ha, 60 kg/ha, 45 kg/ha and 0 kg/ha。When soil fertility are classified as low, medium, high and ver high(Olsen-P<5 mg/kg, 5-21mg/kg, 21-34mg/kg, >34mg/kg), respeetively, while potassium fertilizer rates (K2O) are 75 kg/ha, 60 kg/ha, 45 kg/ha and 0 kg/ha(NH4OAc-K<8 mg/kg, 8-71mg/kg, 71-150mg/kg, >150mg/kg). Therefore, establishing feriilization recommendation index based on"3414"field experimental data is practieable.