氮磷钾平衡施用对花椰菜经济产量及品质的影响

应用311－A拟饱和最优回归设计和{3，2}单形格子饱和设计，通过氮磷钾肥配比和氮肥分期施用田间试验，拟建花椰菜施用氮磷钾肥对经济产量、施肥利润及氮肥分期施用比例的效应函数。寻优结果表明：花椰菜最高产量的氮、磷、钾优化施肥组合为N 249.28、P2O554.33和K2O 238.83kg/hm2，其最高经济产量达54.877t/hm2；最佳施肥利润的氮、磷、钾优化施肥组合为N 243.52、P2O552.22和K2O 234.09kg/hm2，其最佳施肥利润达63784.89元/hm2，经济产量也达54.853t/hm2；较佳施氮分配比例为基肥 ：前期追肥 ：后期追肥为0.3135:0.4500:0.2365，其对应的氮肥用量分别为N76.49、109.80和57.71kg/hm2，期望较高的经济产量可达55.313 t/hm2。在同等肥底下，花椰菜维生素C、还原糖和总糖含量与施氮量之间呈一定程度上的负相关，与磷、钾施用量之间呈不同程度的正相关；而硝酸盐含量则与氮施用量呈一定程度的正相关，与磷、钾施用量之间相当程度的负相关。在磷钾用量相同的情况下，氮肥越迟施用或后期施用量越大，花椰菜维生素C、还原糖和总糖含量越低，但硝酸盐含量则越高。

Study on Effect of Cauliflower Economic Yield and Quality Balanced Fertilization with NPK

The effect functions of NPK application on economical yield, fertilization benefit and N ratio of split application at different growing periods of cauliflower(Brassica oleracea var. botrytis) were studied by the field experiments with 311-A best regression design of supposed saturation and {3, 2} saturated design of single shape check. The results showed that the best NPK application of cauliflower with maximum economical yield of 54.877t/hm2 was N249.28, P2O554.33 and K2O 238.83kg/hm2, the best NPK application with the best fertilization benefit of 63784.89 yuan/hm2 and higher economical yield of 54.853t/hm2 was N243.52, P2O552.22 and K2O 234.09kg/hm2, and betterratio of N split application as basal dressing, former and latter topdressing for higher expecting economical yield of 55.313t/hm2 was 0.3135:0.4500:0.2365, and the N rates were 76.49, 109.80 and 57.71kg/hm2, respectively. Under equal fertilizer, there was the negative correlation between vitamin C, reducing sugar and total sugar content of cauliflower and N application on certain level, with PK application the positive correlation; And the nitrate content with N application the positive barrier that submits certain level , with PK application the negative correlation of considerable level. In PK application the condition with identical quantity take off, N application the later or latterdressing the bigger, vitamin C, reducing sugar and total sugar content of cauliflower are the more lower, but the nitrate content is higher.