基于饱和D-最优设计的‘燕山早丰’施肥研究
Optimal fertilization for Castanea mollissima ‘Yanshanzaofeng’ based on the saturated D-optimal design.
-
摘要: 以8年生盛果初期的板栗主栽品种‘燕山早丰’为研究对象,采用N、P、K三因素二次D-饱和最优设计,在河北省迁西县典型山地连续2年进行田间试验,研究了N、P、K配合施用对板栗产量的影响。通过建立以N、P、K施肥量编码值为变量因子,产量为目标函数的三元二次数学模型,优化施肥量及N、P、K配比。结果表明:N、P2O5、K2O对板栗产量的影响极为显著,同时两两之间存在显著的交互效应。N、P2O5、K2O对板栗产量影响的大小依次为NP2O2K2O。其中,对板栗产量影响最大是N,其次是P2O5,K2O影响相对较小;通过效应函数的频率分析寻优可知,目标产量超过1.62 kg/株、置信区间为95%时,N、P2O5、K2O优化施肥方案为:N 0.85~1.19 kg/株,P2O5 0.65~0.80 kg/株,K2O 0.53~0.64 kg/株。N、P2O5、K2O最佳施肥质量比为1∶0.55~0.94∶0.45~0.75。对边际产量方程分析显示,当施肥量分别为N 1.123 0 kg/株、P2O5 0.754 0 kg/株、K2O 0.612 0 kg/株时,板栗产量最高,此时的产量为1.75 kg/株,N、P2O5、K2O最佳施肥质量比为1∶0.67∶0.54。Abstract: We investigated the effects of a combined application of N, P and K on the yield of 8-year-old Chinese chestnut (Castanea mollissima) ‘Yanshanzaofeng’ cultivars, planted in Xiqian County of Hebei Province, over a two year period of field experiments, using a three-factor two-equation D-saturation optimal design. Based on our data obtained, the amounts of fertilization and the ratios of N, P and K were optimized with a mathematical model, in which the amounts of fertilization of N, P and K were independent variables and yield as our target variable. The results indicated that the yield was significantly affected by the application of N, P2O5 and K2O, with statistically significant interactive effects between all two factor levels. In descending order in the effect of N, P2O5 and K2O on the yield was NP2O5K2O. Results of a frequency analysis of their effect revealed that the target yield could exceed 1.62 kg per plant at a confidence interval of 95%, with the following levels of optimal fertilization: N 0.85-1.19 kg N per plant, 0.65-0.80 P2O5 kg and 0.53-0.64 K2O kg per plant. The best mass ratio of NP2O5K2O was 10.55-0.940.45-0.75. The results of the marginal yield equation showed that the yield could reach a maximum of 1.75 kg per plant with the following amounts of fertilizers: N 1.123 0, P2O5 0.754 0 and K2O 0.612 0 kg per plant and the best mass ratios of NP2O5K2O was 10.670.54.