Abstract: 【Objective】To provide a theoretical basis for balanced fertilization of rapeseed production in the middle of Sichuan hilly regions, abundance and deficiency indexes of soil nutrient and fertilization recommendation indexes were established. 【Method】Data were analyzed based on the “3414” experiments of rapeseed in the field from 2005 to 2009. Making use of plentiful-lack of soil nutrient as an index, soil available phosphorus (AP) and available potassium (AK) were divided into five levels on the basis of different relative yields. Nitrogen fertilizer application rate (N) on average was estimated based on the method of total quantity control, while phosphorus fertilizer (P2O5) and potassium fertilizer application rates (K2O) were calculated by the method of fertilizer response function. 【Result】 Regional optimal application rate of chemical fertilizer N on average is (170±50) kg•hm-2. Phosphorus fertilizer application rates (P2O5) are 100-120,70-100, 50-70, 30-50, ＜30 kg•hm-2 (AP＜5, 5-15, 15-25, 25-45 and ＞45 mg•kg-1), while potassium fertilizer application rates (K2O) are 90-110, 70-90, 50-70, 30-50, ＜30 kg•hm-2 (AK＜30, 30-60, 60-120, 120-240 and ＞240 mg•kg-1). 【Conclusion】Compared with the fertilization recommendation rate calculated by the original system, the fertilization recommendation rate above suggests that nitrogen and phosphorus fertilizer application rates should be decreased, while potassium fertilizer application rates ought to be increased.

Key words: rape , relative yield , nutrient plentiful-lack index , fertilization recommendation