滴灌条件下不同N、K肥施用量对春小麦生长和产量的影响

为了探究西北旱区滴灌水肥一体化条件下最适合春小麦生长和高产的N、K肥施用量，通过田间小区试验，研究了滴灌条件下不同的施N水平(0、80、160、240 kg/hm²)和施K水平(0、88、176、264 kg/hm²)对甘肃春小麦生长和产量的影响。结果表明，在较低水平下，增施N、K肥对春小麦的生长有不同程度的促进作用，施用过量则会抑制其生长。在磷肥(P2O5)和钾肥(K2O)用量分别为60 kg/hm²、176 kg/hm²情况下，N0水平下春小麦平均产量为5813 kg/hm²，N1水平下产量为6563 kg/hm²，比N0增产10.6%~ 15.3%，N2水平下产量为7025 kg/hm²，比N0增产19.1%~22.5%。不同K肥水平下春小麦产量差异不显著，但是同一N、P水平下，随着施钾量的增加，春小麦产量出现先增后减的抛物线趋势。通过试验初步确定，滴灌条件下该地区春小麦达到高产的适宜氮肥(N)用量为150~160 kg/hm²，钾肥(K2O)用量为88 kg/hm²。

Effect of Different Application Rates of N and K Fertilizers on the Growth and Yield of Spring Wheat Under Drip Irrigation

Field experiment was conducted to study the optimum application rate of N and K fertilizer on the growth and yield of spring wheat under drip irrigation in an arid area of Northwest China. Four nitrogen fertilizer treatments (0, 80, 160, 240 kg/hm2) and four potassium fertilizer treatments (0, 88, 176, 264 kg/hm2) were set up. The results showed that, increasing application of nitrogen and potassium fertilizer at low level could promote the growth of spring wheat to some extent, but overuse of fertilizer might inhibit its growth. The combination of nitrogen and potassium fertilizer could increase the yield of spring wheat significantly. The average yield in N0 treatments was 5813 kg/hm2. In contrast, the average yield in N1 treatments was 6563 kg/hm2, which was 10.6%-15.3% higher compared to the control treatment. The average yield in N2 treatments was 7025 kg/hm2 which was 19.1%-22.5% higher compared to the control treatment under identical potassium fertilizer (K2O 176 kg/hm2) and phosphatic fertilizer (P2O5 60 kg/hm2) level. There was no significant difference in yields among treatments under different potassium fertilizer levels. However, there was moderate increase of yield with increase of K fertilizer which present parabolic trend under identical N and P level. The optimal application of nitrogen and potassium fertilizers under drip irrigation was recommended primarily as N 150-160 kg/hm2 and K2O 88 kg/hm2.