Abstract: In order to explore the effects of different ratios of N, P and K fertilizers on the root traits and yield of annual Platycodon grandiflorum, and screen the optimal ratio of N,P,K fertilization, the design method of “3414” field fertilizer was adopted. The root length, root diameter, number of lateral roots, and fresh weight of the annual Platycodon grandiflorum were investigated, and SPSS software was used to analysis of variance and multiple comparisons. The results showed that there were significant differences in the root traits among 14 species of Platycodon grandiflorum. The appearance quality of roots and the yield of Platycodon grandiflorum were better than that of CK without proper fertilization. Rational N,P,K could increase the yield and  appearance quality of Platycodon grandiflorum, the better fertilization ratio were T9（N∶P2O5∶K2O = 88∶174∶450, kg/hm2）, T5 （N∶P2O5∶K2O = 88∶174∶300, kg/hm2）, and potassium fertilizer had an important effect on the increase of annual Platycodon grandiflorum. According to the regression analysis, the optimal ratio of nitrogen, phosphorus and potassium fertilization was N∶P2O5∶K2O = 67.2∶190∶450 (kg/hm2), which was the formulation of fertilization scheme for the cultivation of Platycodon grandiflorum and the research of special fertilizer.

Key words: Platycodon grandiflorus, N,P,K ratio, root traits, yield

摘要： 为探讨氮、磷、钾不同肥料配比对一年生桔梗根部性状和产量的影响，以及初步筛选试验范围内最佳氮、磷、钾施肥配比，采用“3414”田间肥料的试验设计方法对一年生桔梗的根长、根径、侧根数、单根鲜重等性状加以调查，利用SPSS数据分析软件进行方差分析及多重比较。结果表明：14种处理的桔梗根部性状等均存在显著性差异，施肥处理的根部外观品质和桔梗产量综合表现好于不施肥处理CK，合理的氮、磷、钾配施可以提高桔梗的产量和根部外观品质，外观品质最好和产量最高的施肥配比为T9(N∶P2O5∶K2O=88∶174∶450，kg/hm2)、T5(N∶P2O5∶K2O=88∶174∶300,kg/hm2），且钾肥对一年生桔梗的增产有重要影响。经回归分析建立了在试验设计范围内最佳氮、磷、钾施肥配比为N∶P2O5∶K2O=67.2∶190∶450（kg/hm2），可为今后桔梗栽培施肥方案的制定和专用肥料的研究提供参考。

关键词: 桔梗, 氮、磷、钾配比, 根部性状, 产量