抄録
In 1949 experiments were performed in order to explain the relation between the characteristic properties of the underground parts of paddy rice plants and the comparative varietal drought resistance, using the same materials and methods as those of the primary report. The results are summarized as follows: 1. Almost pararell relation was recognized between drought resistance and following characters of root system; root number, sum total of root length, depth and distribution of roots in underground section. (Cf. Table 1) 2. Same results were recogniged as to the new produced root profil except the root number. (Cf. Table 2) 3. In the 3rd observation, drought resistance was more or less related with the length of the longest root in a stock, but scarecely with the other root characters. (Cf. Table 3) 4. It was proved that in the case of supplication of silicic acid the root system developed vigorously and the dry weight of roots under a stock conspicuously increased. (Cf. Table 3 & plate 1.)
