黄芩产量和黄芩苷含量对氮磷钾肥料的响应

通过田间试验,采用氮、磷、钾三因素二次饱和D-最优设计施肥方案,于收获期计算黄芩产量和根中黄芩苷含量,建立以氮、磷、钾施用量为自变量,黄芩产量和根中黄芩苷含量为目标函数的三元二次多项式数学模型,通过对模型进行解析、寻优获得最适施肥量.结果表明:氮、磷对黄芩产量有显著影响,在低水平施肥条件下,产量随施肥量的增加而增大,一定范围后,增效不明显；氮、磷、钾对黄芩苷含量均有显著影响,黄芩苷含量随氮、钾施用量增加呈先降低再增高的趋势,在低水平施磷条件下,黄芩苷含量随磷肥施用量增加而增加,最终趋于稳定.氮磷、氮钾、磷钾对黄芩产量和黄芩苷含量存在明显的交互作用.本试验条件下,黄芩产量超过4000 kg·hm-2、根中黄芩苷含量14％以上的施肥方案为氮(N)90.5～104.7 kg· hm-2、磷(P2O5) 163.9 ～ 199.9 kg·hm-2、钾(K2O)84.1 ～140.8 kg·hm-2,比例约为1∶1.86∶1.15.

Responses of Scutellaria baicalensis Georgi yield and root baicalin content to the fertilization rates of nitrogen,phosphorus,and potassium

A field experiment with three-factor(N,P,and K) and quadratic saturation D-optimal design was conducted to evaluate the effects of the fertilization rates of N,P,and K on the yield and root baicalin content of Scutellaria baicalensis Georgi at harvesting time.A ternary quadratic polynomial mathematical model was built,in which,the N,P,and K fertilization rates were independent variables,and the yield and root baicalin content were the target functions.Through the analysis of the model,the optimum fertilization pattern was obtained.The results showed that the fertilization rates of N and P had significant effects on the yield of S.baicalensis.Under low fertilization level,the yield increased with increasing N and P fertilization rates;after exceeding definite fertilization range,no obvious effects were observed.N,P,and K fertilization all had significant effects on the root baicalin content.With increasing fertilization rates of N and K,the root baicalin content rates decreased after an initial increase.Under low fertilization level,the root baicalin content increased with increasing P fertilization rate first,and kept stable then.There existed interactive effects between the fertilization rates of N and P,N and K,and P and K on the yield and root baicalin content of S.baicalensis.Under our experimental conditions,the optimum fertilization model for obtaining over 4000 kg·hm-2 of S.baicalensis yield and >14% of root baicalin content was 90.5-104.7 kg·hm-2 of N,163.9-199.9 kg·hm-2 of P2O5,and 84.1-140.8 kg·hm-2 of K2O,with an N:P2O5:K2O ratio of approximately 1:1.86:1.15.