柴沙沙 雷剑 王连军 苏文瑾 刘巧林 沈兴国 杨新笋

摘要：选取淀粉型甘薯[Ipomoea batatas（L.）Lam.]品种鄂薯9号为试验材料进行大田试验，采用二因素裂区设计，主区为不同氮肥水平，副区为不同钾肥水平，研究氮、钾互作对甘薯生长发育规律的影响。结果表明，不施用氮肥时的最佳施钾肥（硫酸钾）量为180 kg/hm2，与不施钾肥相比，增产7.2%;施氮（尿素）量为150 kg/hm2时，施钾肥量为180 kg/hm2产量最高，与不施钾肥相比，增产23.02%;施氮量为300 kg/hm2，施钾量为360 kg/hm2甘薯产量最高，与不施钾肥相比，增产14.16%。由此可知，不管氮肥的施用量是多少，只有在适当施用钾肥的情况下，甘薯才能获得高产。

关键词：甘薯[Ipomoea batatas（L.）Lam.];氮肥;钾肥;产量

中图分类号：S531         文献标识码：A

文章编号：0439-8114（2018）22-0024-03

DOI：10.14088/j.cnki.issn0439-8114.2018.22.008           开放科学（资源服务）标识码（OSID）：

Abstract： Using the starch type sweet potato（Ipomoea batatas） variety Eshu No.9 as the experimental material，the field experiment was carried out. The experiment adopted two-factor crack zone design，which the main area was different nitrogen fertilizer level and the secondary area was different potassium fertilizer level，to research the effects of interaction of nitrogen and potassium on growth and development of sweet potato. The results showed that，when no nitrogen fertilizer was applied，the optimal dosage potassium （potassium sulphate） fertilizer was 180 kg/hm2，which was 7.2% higher than that without potash fertilizer;when the amount of nitrogen（urea） applied was 150 kg/hm2，the yield was the highest of which the amount of potassium fertilizer was 180 kg/hm2，and the yield was 23.02% higher than that without potassium fertilizer; when the amount of nitrogen applied was 300 kg/hm2，the yield of sweet potato was the highest of which the amount of potassium applied was 360 kg/hm2，and the yield was increased by 14.16% compared with that no potassium fertilizer was applied. It shows that no matter how much nitrogen fertilizer is applied，only when the potassium fertilizer is properly applied， the sweet potato can obtain high yield.

Key words： sweet potato[Ipomoea batatas（L.）Lam.]; nitrogen fertilizer; potassium fertilizer; yield

氮、鉀是作物生长发育必需的矿质营养元素[1-4]，甘薯[Ipomoea batatas（L.）Lam.]的生长发育和产量形成与氮、钾密切相关[5-8]。已有研究表明，随着施氮量的增加，甘薯的氮肥偏生产力降低，表观利用率升高，而农学利用率和生理利用率呈先增加后下降趋势;适量施氮显著增加了甘薯块根产量，过量施氮则产量降低[9]。施用钾肥可以提高甘薯的钾素表观利用率和农学利用率，显著提高块根的产量[10];但钾肥用量过高，增产幅度下降[11-13]。

氮、钾肥料配合施用可以显著提高甘薯块根产量[14，15]。当施氮水平较低，甘薯叶片含氮量显著低于适宜水平时，施钾越多越不利于甘薯产量提高[16]。本研究通过设置氮肥和钾肥的二因素裂区试验，分析不同氮、钾配施用量对块根和地上部生长发育的特点，为甘薯生产中的合理施肥提供依据。……