应用15N标记对不同施氮方式甘蔗氮肥利用效率的研究

以新台糖22号(ROC22)为试材,设15N标记尿素作基肥(5g/盆)(T1)、基肥(2.5g/盆)+分蘖肥(2.5g/盆)(T2)及基肥(1.5g/盆)+分蘖肥(1.5g/盆)+攻茎肥(2g/盆)(T3)3个处理,研究施氮方式对甘蔗氮肥利用效率的影响。结果表明,与T1比较,T2、T3极显著提高了甘蔗尤其是蔗根和蔗叶对氮肥的利用效率,其中T3的氮肥利用效率最高;3个处理间甘蔗植株的氮肥偏生产力、吸收的肥料氮、氮素分配率及氮肥利用率等数值差异均达显著水平。氮肥以基肥+分蘖肥+攻茎肥施用最有利于提高甘蔗产量和氮肥利用率。

Effect of Different Application Methods of Nitrogen Fertilizer on Nitrogen Utilization Efficiency in Sugarcane

Three treatments were designed with equal amount nitrogen of 5g 15N-labeled urea per pot but applied in different amount at different developmental stages,to study the effects of N-fertilizer application methods on N utilization efficiency in sugarcane varieties ROC22.T1 received urea 5 g/pot was applied at sowing time;T2 received urea which 2.5 g/pot at sowing time and 2.5 g/pot at tillering stage,respectively;T3 received urea which 1.5 g/pot at sowing time,1.5g/pot at tillering stage and 2.0g/pot at elongation stage,respectively.The results were as follows:compared with T1,N-fertilizer utilization efficiency in sugarcane,especially in roots and leaves was obviously increased in T2 and T3,and N-fertilizer had the most use efficiency in T3.The nitrogen partial factor productivity,NDFF,nitrogen distribution rate and nitrogen utilization rate of sugarcan were significant differences in T1,T2 and T3.The results indicated that the application of N-fertilizer at three developmental stages was the best in nitrogen utilization and enhancing the yield of sugarcane.