抄録
To determine the method for discriminating the stage of yield forecast, the author examined what character of rice may be utilized as an index of the discrimination. The obtained results are as follows. 1) Close relation between the rate of moisture content of ear and grain weight on the ripening stage was found, irrespective of places, years and varieties. Therefore, the ripening process of ear can be discriminated by the former. 2) Furthermore, close relation was found between the rate of moisture content of ear and percentage of milky grains. Therefore, the former can be discriminated by the latter. It was found high correlation between grain yield and fresh weight of ear at the stage when percentage of milky grains bigins to decrease. Frome these results, the stage when percentage of milky grains became 10±3%, seems to be a suitable stag for forecasting yield.