抄録
Rice seedlings were grown by the ordinary water culture technique, the roots were then divided into two parts by the root separation method (Fig. 1) ; one dipped in the ordinary water culture solution containing P^<32>O_4 and the other in the (a) Distilled water (b) Ordinary culture solution with P and (c) Do lacking P respectively. As seen from Table 1. the efflux of P^<32> was insignificant in 48 hours in each plot, but it significantly increased in 48-96 hours, especially in "Distilled Water." The difference in the other two plots was insignificant within experimental error ; the fact might suggest almost no possible efflux of phosphoric acid by "anionic exchange." The minute efflux as contrasted to the P^<32> held in the efflux root (Table 2) might rather be in favour of some very tight combination of PO_4 in the root protoplasm, probably of organic nature. From Table 2 it may be concluded that P^<32> can remarkably move downward in the root simultaneously with the upward movement of not only water and other salts but also even of PO_4.
