减施氮肥对设施黄瓜产量、品质及土壤氮素平衡的影响

Effects of nitrogen reduction on yield,quality of greenhouse cucumber and soil nitrogen balance

为解决设施黄瓜生产中氮肥施用过量、氮肥效率低、氮素损失严重、果实品质变劣等问题,采用田间原位试验法,在农民习惯施氮肥基础上设置不同程度减施氮肥处理,研究各减氮处理对黄瓜产量、品质、土壤氮素转化和氮素利用等的影响。结果表明:农民习惯施氮肥减氮20%(N3)较农民习惯施氮肥(N1)处理的黄瓜Vc、可溶性蛋白质、可溶性糖分别提高8.34%、8.18%、56.78%,黄瓜产量增加3.34%;同时较其他减施氮肥处理的黄瓜Vc、可溶性蛋白质、可溶性糖分别提高7.93%~15.42%、0.79%~37.05%、1.10%~40.00%,黄瓜产量增加1.28%~39.64%。农民习惯施氮肥减氮20%~50%处理(N3~N5)的土壤残留氮累积较其他处理降低22.50%~28.22%,氮盈余量减少15.92%~37.19%。农民习惯施氮肥减氮20%(N3)的氮肥农学效率高于其他处理12.32%~26.76%。农民习惯施氮肥减氮20%能够显著增加设施黄瓜产量、改善品质、减少氮素损失、降低土壤氮盈余量,为设施黄瓜减肥增效提供技术支撑。

Excess nitrogenous fertilizer causes low efficiency of N fertilizer and serious N loss,and also decreased fruit quality in cucumber production.Therefore,this paper studied the effects on cucumber yield and quality,the transformation of soil nitrogen under the field in-situ condition supplying less nitrogen based on common field N application.The results showed that reduced N application promotes cucumber yield and meanwhile improved the fruit quality.Among the treatments,20%reduction of N fertilizer had the best effects that enhanced the yield by 3.34%and increased Vc,soluble protein and soluble sugar by 8.34%,8.18%and 56.78%compared with common N application.Other N reduction treatments also increased Vc,soluble protein and soluble sugar by 7.93%-15.42%,0.79%-37.05%and 1.10%-40.00%,and cucumber yield by 1.28%-39.64%.When N application reduced 20%-50%,soil N residue and surplus were decreased 22.50%-28.22%and 15.92%-37.19%,among which the best effects were identified in 20%reduction treatment.According to the comprehensive analysis,20%N fertilizer reduction(N3)was ideal for field production to promoted yield and fruit quality accompanied by reduction of nitrogen loss and soil nitrogen surplus,which provided technical support for greenhouse cucumber.