PROBLEM TO BE SOLVED: To provide a method for using an available nitrogen quantity to execute highly-accurate fertilization designing, when at least one of a culture medium and a material applied as a fertilizer to the culture medium includes an organic substance.SOLUTION: A fertilization designing method includes: setting a culture-condition parameter value to be used for acquiring a target available-nitrogen quantity that means a proper available-nitrogen quantity in a culture medium (S101) acquiring the proper available-nitrogen quantity corresponding to the set culture-condition parameter value, as the target available-nitrogen quantity, with reference to a database showing correspondence between the culture-condition parameter value and the proper available-nitrogen quantity in the culture medium (S102) acquiring an estimated available-nitrogen quantity in the culture medium (S103) calculating a shortage quantity of available-nitrogen quantity by subtracting the estimated available-nitrogen quantity in the culture medium from the target available-nitrogen quantity (S104) acquiring an estimated available-nitrogen quantity in a material (S105) and determining a material quantity to be applied to the culture medium so as to compensate for the shortage quantity of available-nitrogen quantity, on the basis of the estimated available-nitrogen quantity in the material (S106).COPYRIGHT: (C)2015,JPO&INPIT【課題】培地、および培地に肥料として施用する資材の少なくとも一方が有機物を含む場合において、可給態窒素量を用いて精度の高い施肥設計を行うための方法を提供する。【解決手段】培地の可給態窒素の適正量である目標可給態窒素量を取得するために用いる栽培条件パラメータの値を設定し(S101)、栽培条件パラメータの値と培地の可給態窒素の適正量との対応を示すデータベースを参照して、設定された栽培条件パラメータの値に対応する可給態窒素の適正量を目標可給態窒素量として取得し(S102)、培地の可給態窒素の推定量を取得し(S103)、目標可給態窒素量から培地の可給態窒素の推定量を差し引いて可給態窒素の不足量を算出(S104)し、資材の可給態窒素の推定量を取得し(S105)、資材の可給態窒素の推定量に基づいて、可給態窒素の不足量を補うために培地に施用する資材の量を決定する(S106)。【選択図】図3
