Effects of nitrogen fertilizer application mode on sugarcane yield and soil nutrient change.

【Objective】This study intended to improve use efficiency of nitrogen fertilizer for increasing sugarcane yield and reducing nitrogen pollution in agricultural production. 【Method】With ROC22 as test material, three different nitrogen fertilizer rates (38 kgN/ha, 276 kgN/ha and 414 kgN/ha)and three different application methods (1:10% nitrogen fertilizeras base fertilizer, 30% nitrogen fertilizer applied to soil dressing, 60% applied to big ridging;2:30% nitrogen fertilizer as base fertilizer,70% nitrogen fertilizer applied to soil dressing;3:100% nitrogen fertilizer as base fertilizer)were used to study the relationship among nitrogen, sugarcane growth and soil nutrient changes by investigating sugarcane agronomic characters,yield and soil nutrient. 【Result 】The results showed that sugarcane yield increased with nitrogen rate increasing yield which was the highest at 276 kgN/ha. Nitrogen fertilizer applied earlier could promote sugarcane jointing,early growth and increasing. Soil nitrogen and available potassium content rose with the increasing amount of nitrogen fertilizer. However,the excess nitrogen fertilizer could cause soil acidification. Nitrogen fertilizer applied early could help dissolve soil phosphate and improve phosphorus absorption and utilization. Applying nitrogen fertilizer completely as base fertilizer was likely to cause nitrogen loss and low use efficiency. 【Conclusion】 The appropriate application mode for sugarcane is applied twice at the mount of 138 -276 kgN/ha.