氮肥不同用量对甘薯生长及产量的影响

Effects of Different Nitrogen Application Rates on Growth and Yield of Sweet Potato

以鲁南地区主栽品种商薯19为试验材料,在中等肥力条件下,研究5个氮素水平(666.7m2施氮量分别为0、2.5、5.0、7.5、10.0 kg)对鲜薯产量、薯干产量及氮肥利用率等的影响。结果表明:随着施氮量的增加,甘薯地上部与地下部生长平衡点有延后的趋势,鲜薯产量随施氮量的增加呈先增加后下降的趋势,以666.7m2施氮2.5 kg处理的鲜薯增产效果最好,比不施氮对照提高9.46%,氮肥利用率最高。

Using the sweet potato variety Shangshu 19 as material, under the medium soil fertility condi- tion, five nitrogen levels （0, 2.5,5.0, 7.5, 10.0 kg per 666.7m2） were set to study their effects on fresh tuber yield, dry yield and nitrogen use efficiency. The results showed that with the increase of nitrogen application rate, the equilibrium point of aboveground and underground growth had a delayed trend, and the fresh tuber yield increased first and then decreased. The treatment of 2.5 kg nitrogen per 666.7m2 had the highest fresh tu- ber yield and nitrogen agronomic efficiency, and the yield increased by 9.46% compared with the control.