由于枣树的物候期具显著的重叠性，导致各器官营养竞争激烈。为给枣树氮肥精细化管理提供科学依据，以8年生密植壶瓶枣为指示品种，不施氮为对照，设置5个氮素施用量(0.08、0.12、0.16、0.20、0.24 kg/株)，测定不同氮素水平对壶瓶枣生长及果实品质的影响。结果表明，各施氮处理均有利于壶瓶枣树基径、叶面积的增大，对生长后期叶片叶绿素含量的影响较小。当施N 0.16 kg/株分别在萌芽期、花期、果实膨大期按施氮总量的40%、30%、30%施入时，壶瓶枣树生长良好，枣果品质综合表现最优，单果重、果实横径、可溶性固形物含量、可溶性糖含量、糖酸比均达到最大值，分别较不施氮增加61.29%、17.64%、6.23%、28.04%、55.51%；果实纵径较不施氮增加9.42%；总酸含量低，较不施氮降低17.47%。因此认为，在试验设计范围内，施N 0.16 kg/株是武威枣园及类似生态区域促进密植壶瓶枣生长和提高枣果品质的最佳施氮量。

Due to the significant overlap in the phenological stages of jujube trees, there is intense competition for nutrients among various organsin jujube trees. To provide scientific basis for precision management of nitrogen fertilization in jujube trees, 5 nitrogen application rates (0.08, 0.12, 0.16, 0.20 and 0.24 kg/plant) were set up in 8-year-old densely planted Ziziphus jujuba Mill. cv. 'Hupingzao' plants to determine the effects of different nitrogen levels on the growth and fruit quality of 'Hupingzao'. The results showed that all nitrogen application treatments were conducive to the increase of the basal diameter and leaf area of 'Hupingzao' trees and had little effect on the chlorophyll content in leaves at the late growth stage. The single fruit weight, fruit cross diameter, contents of soluble solids and total sugar, and sugar acid ratio were the highest under the nitrogen application rate of 0.16 kg/plant (nitrogen application rate were set at 40%, 30% and 30% of toal nitrogen fertilizer applied in the early germination, flowering and fruit expansion stages, respectively), which were 61.29%, 17.64%, 6.23%, 28.04%, and 55.51% higher than those of the control,no nitrogen application, respectively, the vertical diameter of the fruitwas increased by 9.42% compared with that of the control, no nitrogen application, and the total acid content was reduced by 17.47% compared with that of the control, no nitrogen application. In conclusion, under the conditions of this experiment, nitrogen application rate of 0.16 kg/plant was the optimal nitrogen application rate for the growth and fruit quality improvement of 'Hupingzao' in Wuwei and other areas with similar conditions.

S665.1；S147.2

甘肃省林业科技项目(2018kj029)。