A good understanding of the relationship between vegetable quality and soil N balance is very important for proper nitrogen (N) management for crop productions. In this study, a field experiment was carried out to investigate the N application rate and times on Chinese cabbage yield and quality, N use efficiency, soil nitrate-N concentration, and soil pH. The experiment was implemented in a two-way factorial design and the two factors comprises of number of N applications (once, twice and three times, denoted as T1, T2 and T3) and N rates (15%, 30% and 45% less than conventional rates (CF), denoted as F1, F2 and F3, respectively). The treatments were also compared with a no-fertilizer blank and a control (CF) with a conventional N management practice. The results showed that the highest yield of cabbage (164.65 t hm⁻²), Vitamine C content (14.80 g 100 g⁻¹ fresh mass), soluble sugar content (2.33 mg kg⁻¹), plant N uptake (119.2 kg hm⁻²) were obtained under T3F1 treatment. Compared with CF treatment, T3F1 treatment significantly increased vegetable yield, vitamin C and soluble sugar content in fruit, and nitrogen use efficiency by 10.97%, 13.76% and 17.68%, and 18.76%, respectively. Nitrate-N content in cabbage was reduced by 7.55% in T3F1 treatment. With the reduced N application rate, soil pH gradually changed from 6.25 to 7.26. T3F1 treatment is a most suitable N management practice for vegetable production, in terms of higher vegetable yield and quality, soil N content, depressed soil acidification and nutrient uptake by Chinese cabbage.

正确理解蔬菜质量与土壤氮平衡之间的关系对于作物生产中适当的氮素管理非常重要。本研究进行了田间试验，研究了氮肥的施用量和施用时间对大白菜产量和品质，氮素利用效率，土壤硝态氮浓度和土壤pH的影响。该实验以双向析因设计进行，两个因素包括N个应用的次数（一次，两次和三倍，分别表示为T1，T2和T3）和N发生率（分别降低15％，30％和45％）比常规费率（CF）分别表示为F1，F2和F3）。还将处理与不施肥空白和对照（CF）与常规氮管理实践进行比较。结果表明，最高的白菜产量（164.65 t hm ^-2），在T3F1处理下获得维生素C含量（14.80 g 100 g ^-1新鲜质量），可溶性糖含量（2.33 mg kg ^-1），植物氮吸收（119.2 kg hm ^-2）。与CF处理相比，T3F1处理显着提高了蔬菜产量，水果中的维生素C和可溶性糖含量以及氮素利用率，分别提高了10.97％，13.76％和17.68％和18.76％。在T3F1处理中，白菜中的硝酸盐氮含量降低了7.55％。随着氮肥施用量的减少，土壤pH从6.25逐渐变化到7.26。从更高的蔬菜产量和品质，土壤氮含量，降低的土壤酸化程度和大白菜吸收养分的角度考虑，T3F1处理是最适合蔬菜生产的氮素管理实践。