PROBLEM TO BE SOLVED: To provide a growth management method for accurately predicting yield and quality of gramineous crops and improving yield and quality. SOLUTION: For gramineous crops, the nitrogen satisfaction index before and after the maximum tillering period and the ear matching period are obtained by measurement, respectively, and the nitrogen satisfaction index before and after the maximum tillering period is the first explanatory variable, the maximum tillering period. The increase in the nitrogen satisfaction index from to the ear matching period was used as the second explanatory variable, and multiple regression analysis was performed on both explanatory variables and the corresponding paddy number and one ear paddy number, and the paddy number corresponding to both explanatory variables. Obtain a prediction formula for the number of rice ears, obtain the nitrogen satisfaction index by measurement before and after the maximum tillering period in the growth process of the crop, and correlate the number of rice ears and the number of rice ears and the index of crop quality separately obtained. Based on the target number of paddy and the number of one ear of paddy set from the relationship and the prediction formula of the number of paddy and the number of one ear of paddy, the target number of paddy and one ear from the maximum tillering period to the matching period A method of fertilizing by determining the amount of increase in the nitrogen satisfaction index required for the number of paddy and the amount of additional fertilizer applied accordingly. [Selection diagram] Fig. 6【課題】イネ科作物について、収量、品質を精度よく予測し、収量、品質を高める生育管理方法を提供する。【解決手段】イネ科作物について最高分げつ期前後及び穂揃い期における窒素満足指数をそれぞれ計測により求め、最高分げつ期前後の窒素満足指数を第１の説明変数、最高分げつ期から穂揃い期までの窒素満足指数の増加量を第２の説明変数とし、両説明変数と、対応する籾数、一穂籾数とに関して重回帰分析を行って両説明変数に応じた籾数、一穂籾数の予測式を得ておき、作物の成育過程において、最高分げつ期前後に計測により窒素満足指数を求め、別途求めた籾数、一穂籾数と作物の品質の指標との相関関係から設定される目標とする籾数、一穂籾数の値と、籾数、一穂籾数の予測式とをもとに最高分げつ期から穂揃い期までに目標とする籾数、一穂籾数となるのに必要な窒素満足指数の増加量、それに応じた追加施肥量を
