Abstract
In order to know whether application of red colored hill soil to rice fields has good effects not only in the case of ordinary transplanting but in the case of early transplanting culture, and moreover to find the optimum quantity of nitrogenous fertilizers in the latter case, some experiments were carried out by the authors, the results obtained being as follows: [I] Effects of red colored hill soil put in, (a) A larger number of ears was obtained. (b) Good harvests were obtained. (c) The elongation of lower internodes were controlled. (d) Total nitrogen content in the plant decreased. (e) In consequence of the results (c) and (d), the plant became lodging resistant. The tendency above rnentioned was distinctly noticed especially in early transplanting. [II] Effects on early transplanted rice crop, (a) Decrease in a thousand grain weight of rice often liable to application of abundant nitrogenous fertilizers was checked by hill soil duplication. (b) A larger number of ears was obtained. [III] Effects on three kinds of ill-drained paddy fields which consist of mack, sandy soil and heavy clay, respectively, showed a similar tendency as above mentioned in all cases. From those facts there were elucidated good effects of red colored hill soil put in early transplanted rice fields under ill-drained condition. Crop damages frequently caused by heavy fertilizing may be thus controlled to some extent.