Abstract
This experiment was carried out in order to clarify the effect of defoliation on the appearance and elongatiion of root in oats. The investigation was made on each shoot unit (leaf internode unit) after defoliation. The materials were grown in "fog-box" for convenience of root observation. The amount of root was reduced by defoliation treatment. The reduction in the amount of root was also caused by the following factors. 1. Stoppage or reduction in the appearance of root in the third shoot unit from the one in which leaf blade was expanding at the time of defoliation treatment. 2. Retardation of elongation and branching of root. 3. Retardation of root appearnace as a consequence of retardation of plant aging.
