桔梗氮、磷、钾施肥效应与施肥模式研究

采用氮、磷、钾三因素2次D-饱和最优设计(310),通过大田试验建立了氮、磷、钾施肥量与桔梗产量和总皂苷含量的效应函数。结果表明,氮、磷、钾肥对桔梗产量的影响大小依次为氮肥 钾肥 磷肥;氮、磷、钾肥对桔梗总皂苷含量的影响大小依次为氮肥 磷肥 钾肥。对各效应函数进行频率分析法寻优结果表明,桔梗目标产量在4200～4800 kg/hm2,95%置信区间的优化施肥量为N 83.72～119.41 kg/hm2、P2O5 64.10～134.39 kg/hm2、K2O 78.80～147.20 kg/hm2;桔梗总皂苷含量在5.5%以上,95%置信区间的优化施肥量为N 113.37～140.12 kg/hm2、P2O5 85.96～153.44 kg/hm2、K2O 76.86～136.38 kg/hm2;桔梗高产优质高效栽培最优施肥量为N 113.37～119.41 kg/hm2、P2O5 85.96～134.39 kg/hm2、K2O 78.80～136.38 kg/hm2,N、P2O5、K2O的最优施用量配比为1︰0.72～1.18︰0.66～1.20。

Effects and models of nitrogen,phosphorus and potassium fertilization for Platycodon grandiflorum

The effect functions of nitrogen,phosphorus and potassium application codes on the yield and total saponin of Platycodon grandiflorum were established by conducting field experiments using three-factor D-saturation optimal design(310).The results show that the effects of nitrogen,phosphorus and potassium on yield and total saponin are nitrogen > potassium > phosphorus and nitrogen > phosphorus > potassium respectively.The results of the frequency analysis show that for the target yield between 4200 and 4800 kg/ha and confidence interval 95%,the optimal fertilizer application rates of N,P2O5 and K2O,are 83.72-119.41,64.10-134.39 and 78.80-147.20 kg/ha respectively,and for the total saponin content over 5.5%,the optimal fertilizer application rates are 113.37-140.12,85.96-153.44 and 76.86-136.38 kg/ha,respectively.Consequently,the optimal fertilizer application rates for both high yield and high quality of Platycodon grandiflorum are 113.37-119.41,85.96-134.39 and 78.80-136.38 kg/ha,respectively.The corresponding fertilizer ratio of N∶ P2O5 ∶ K2O is 1 ∶ 0.72-1.18 ∶ 0.66-1.20.