A field experiment was carried out to investigate the effect of combined application of ammonium and nitrate on the growth,nutrient utilization and yield of mini Chinese cabbage (Brassica pekinensis vs Jinchengxiahuang).Results showed that combined application of ammonium and nitrate fertilizer could increase the accumulation of dry matter in all parts of the mini Chinese cabbage in the heading stage compared with single nitrogen fertihzer.The combined application also significantly increased yield,total nitrogen,total phosphorus,total potassium content in each part of the plant treatment,nutrient use efficiency,the root bleeding intensity during every growth period.Additionally,when ratio of the ammonium and nitrate fertilizer was 7 ∶ 3,the root dry matter accumulation,NPK uptake and root bleeding intensity of the mini Chinese cabbage were significantly higher than that in single nitrogen fertilizer.The root dry matter accumulation was 2.16 g·plant-1,and NPK uptake was 5.92 g·kg-1,4.44 g·kg-1,6.05 g·kg-1 in the harvesting stage.The root bleeding intensity were 8.09 g· h-1 in the heading stage.When the ratio was 5 ∶ 5,yield and nitrogen use efficiency significantly increased,and the transfer of nutrients from different organs of to leaf ball was promoted.In the harvesting stage the dry matter weight,nitrogen use efficiency,economic output were 34.50 g,6.89％,114.16 t·hm-2.We concluded that the optimal ratio of the ammonium and nitrate fertilizer was 5 ∶ 5 to promote the mini Chinese cabbage production.%在大田试验条件下,以娃娃菜(Brassica pekinensis)栽培品种‘金城夏黄’为试验材料,研究了铵态和硝态氮肥配施比例对娃娃菜生长、养分吸收利用及产量的影响.结果表明,与单一氮源施肥相比较,铵态和硝态氮肥配施可以提高娃娃菜结球期各器官干物质、全氮、全磷、全钾的积累和根系伤流强度,显著地增加氮素利用效率和产量.当NO3--N∶ NH-4+-N=3∶7时,有利于娃娃菜根部干物质和养分的积累,增强根系伤流强度,在采收时,根部干物质达到2.16 g·株-1,NPK分别达到5.92,4.44,6.05 g·k g-1,结球期根系伤流强度为8.09 g·h-1;NO3--N∶NH4+-N=5∶5时,能够促进娃娃菜结球期各器官的养分向叶球转运积累,显著增加叶球干物质重量、氮素利用效率和产量,在采收时,叶球干物质重量、氮肥利用率和经济产量分别达到34.50 g·株-1、6.89％和114.16 t·hm-2.因此,NO3--N∶ NH4+-N=5∶5是适宜高原夏季娃娃菜生产的最佳铵硝配施比例.
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