应用“肥料量级”试验建立吉林省春玉米磷肥施用指标体系

应用“肥料量级”试验结果建立吉林省适宜春玉米生产体系的磷肥施肥技术指标体系。本研究以相对产量75%，90%和95%为标准将吉林省土壤有效磷划分为低、中、高和极高4级；并用一元二次加平台模型对不同土壤养分分级范围内施肥量与产量关系进行模拟，计算最佳磷肥用量。研究结果表明：当吉林省土壤有效磷含量处于低等级(Olsen-P＜5mg/kg)时，磷肥(P2O5)用量应为83 kg/ha；中等级(Olsen-P 5-21 mg/kg)时，磷肥用量为60 kg/ha；高等级(Olsen-P 21-34 mg/kg)时，磷肥用量为45kg/ha；当土壤有效磷高于34 mg/kg时，短期内无需磷肥施用。

Establishing phosphorus fertilization recommendation index based on the “fertilizer rate” field experiments in Jilin province

Taking the spring maize “fertilizer rate” experiments in Jilin Province as an example, the process of establishing fertilization recommendation index was investigated. Soil Olsen-P 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. P 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）, respectively.