设施栽培条件下番茄适宜的氮素管理和灌溉模式

Study on Nitrogen Management and Irrigation Methods of Greenhouse Tomato

【目的】探索设施栽培条件下番茄适宜的氮素管理和灌溉模式。【方法】试验设4个处理:对照、传统氮素管理、优化氮素管理和推荐氮素管理。比较不同处理间的番茄产量、氮肥追施量、氮素损失量、化学氮肥和灌溉水农学效益等。【结果】(1)对照处理未追施化学氮肥,产量仍达到较高水平,冬春季出现了随着氮肥追施量的增加而减产的现象。(2)传统氮素管理每季的氮肥追施量为600kgN·hm-2,灌溉量约7500m3·hm-2,不合理的水氮管理造成每年1416kgN·hm-2的表观氮素损失;与传统处理相比,推荐氮素管理每季番茄氮肥追施量减少50%,全年氮肥损失量减少32.2%;优化氮素管理两季番茄氮肥追施量为314和124kgN·hm-2,灌溉量分别为3900和4550m3·hm-2,全年的氮肥损失量减少38.6%。(3)传统、优化和推荐氮素管理全年的化学氮肥农学效益为0、24.9和0.3kgFW·kg-1N,传统和优化灌溉的灌溉水农学效益分别为12.2和23.2kgFW·m-3。(4)优化氮素管理模式每年可减少4000元/hm2的氮肥和灌溉用电费用。【结论】本试验条件下,氮肥追施量已不是番茄产量进一步提高的主要限制因素。氮素追施调控结合小管出流及夏季休闲时施用小麦秸秆和氰氨化钙的水氮管理是较优的番茄氮素管理和灌溉模式。

[Objective] Nitrogen management and irrigation model of greenhouse tomato were studied. [Method] Four treatments, control （CK）, conventional nitrogen （CN）, optimized nitrogen （ON） and recommended nitrogen （RN） management treatments were designed to investigate tomato yield, N application rate, loss of N, the agronomic efficiency of chemical N fertilizer and irrigation water. [ Result ] Tomato yield of CK reached a higher level although any chemical N fertilizer was not used, the phenomenon of yield reduction appeared with the increasing of the rate of N sidedressed in winter-spring season. The rate of N sidedressed of CN is 600 kgN.hm^-2, and the irrigation water is about 7 500 m^3-hm^-2, there are 1 416 kgN.hm^-2 has been lossed as the result of the unreasonably water and N management; Compared with CN, the loss sidedressed N and the loss of total N decreased by 50% and 32.2% in RN; The rate of N sidedressed of ON is 314 and 124 kgN.hm2 in two seasons respectively, and the irrigation water is 3 900 and 4 550 m^3.hm^-2, with the total loss of N reduced by 38.6%. The agronomic efficiency of chemical N fertilizer in CN, ON and RN treatments in the whole year is 0, 24.9 and 0.3 kgFW.kg^-1N, respectively. Tha agronomic efficiencies of irrigation water of the conventional and optimized irrigation treatments are 12.2 and 23.2 kgFW.m^3, respectively. The ON can reduce 4 000 yuan/hm^2 by decreasing N fertilizer and irrigation water input. [Conclusion ] The rate of N sidedressed is not the leading factor restricting the increase of tomato yield. Water and N management mothods of optimizing N sidedressing and irrigation by employing bubbler irrigation system during the growing season, and applying calcium cyanamide mixed with wheat straw in summer-fallow are considered as the better water and N management.