不同叶龄期穗肥对籼稻产量及氮肥利用效率的影响

为了降低氮肥用量,提高其利用效率,在不施基蘖肥的条件下,研究了不同叶龄期施穗肥对籼稻产量及氮肥利用效率的影响。结果表明,倒5叶施60%+倒3叶施40%氮肥(T3,氮肥用量120 kg/hm~2)、倒4叶施100%氮肥(T4,氮肥用量120 kg/hm~2)、倒4叶施60%+倒2叶施40%氮肥(T5,氮肥用量120 kg/hm~2)、倒5叶施100%氮肥(T2,氮肥用量120 kg/hm~2)、均施氮肥(CK,氮肥用量195 kg/hm~2)的产量分别为12.90、12.74、12.69、12.32、13.25 t/hm~2,氮肥贡献率分别为17.71%、16.58%、16.25%、13.77%、19.86%,氮肥农学利用率分别为18.08、16.73、16.33、13.26、13.24kg/kg。总之,倒5叶施60%+倒3叶施40%氮肥的处理比均施氮肥处理氮肥用量减少38.46%,但产量及氮肥利用率差异不大。

Effects of Ear Fertilizer in Diffferent Leaf Age on Yield and Nitrogen Use Efficiency of Indica rice

In order to reduce the amount of nitrogen fertilizer and improve its use efficiency, the effects of ear fertilizer in different leaf age on yield and nitrogen use efficiency of indica rice was studied without the application of base fertilizer and tiller fertilizer. The re-sults showed that, for 5 leaf stage(60％)and 3 leaf stage(40％)poured nitrogen fertilizer(T3, 120 kg/hm2), 4 poured leaf stage(100％) nitrogen fertilizer(T4, 120 kg/hm2), 4 leaf stage(60％)and 2 leaf stage(40％) poured nitrogen fertilizer(T5, 120 kg/hm2), 5 poured leaf stage(100％)nitrogen fertilizer(T2, 120 kg/hm2), four times average application of nitrogen fertilizer(CK, 195 kg/hm2), the rice yields were 12.90, 12.74, 12.69, 12.32, 13.25 t/hm2, nitrogen contribution rate were 17.71％, 16.58％, 16.25％, 13.77％, 19.86％, and agronomic nitrogen utilization rate were 18.08, 16.73, 16.33, 13.26, 13.24 kg/kg, respectively. Compared with CK, the amount of nitro-gen fertilizer of the treatment with 5 leaf stage(60％)and 3 leaf stage(40％)poured nitrogen fertilizer was reduced by 38.46％, but the grain yield and nitrogen use efficiency difference was not significant.