桂林市雁山区马蹄高产氮磷钾肥配比研究

为摸清雁山区土壤基础养分（氮磷钾）含量，探索马蹄的氮磷钾肥的最佳施肥配方，2009年在雁山区进行了马蹄“3414”肥料效应田间试验。结果表明，该试验点土壤的氮含量为低水平，磷、钾含量为中等水平。根据肥料交互作用分析结果，氮、磷、钾的交互作用最高，其次是氮钾的交互作用，最差的是磷钾的交互作用。根据各处理施肥量和马蹄产量，建立了三元二次及一元二次肥料效应模型，根据肥料和马蹄的价格，计算出马蹄最高产量的施肥量和最佳经济效益的施肥量。通过比较，在本试验条件下，选择三元二次肥效模型的最佳产量施肥量作为推荐施肥量，即：N 386．02kg／hm2、P2O5146．69kg／hm2、K2O 395．55kg／hm2。

Experiment report on fwater chestnuts NPK fertilizer proportion in Yanshan District of Guilin

To find out the soil-based nutrients （NPK） content of Yanshan District, and explore the best fertilization proportion for water chestnuts, in 2009, water chestn＂3414＂fertilizer effect experiment was conducted in Yanshan District . The results show that in the experiment field, the soil has low nitrogen, middle phosphorus and potassium contents. Based on the results of nitrogen, phosphorus, potassium fertilizer interaction, interaction analysis shows that NPK has the ighest interaction, followed by the interaction of N and K, the worst is the interaction of P and K. According to the fertilization amount in treatments and water chestnuts yields, a ternary quadratic effect of fertilization and a quadratic model were established. Based on the price of fertilizer and water chestnuts, the maximum fertilization amount for highest yield and the best cost-effectiveness fertilization amounts will be calculated out. By comparison, in this experimental condition, the best model of ternary quadratic yield-fertilization amounts are recommended,namely： N 386.02kg/hm2,P2O5 146.69kg/hm2,K2O 395.55kg/hm2.