1. To separate P^<32> from Ca^<45> we devised a method, depending upon making use their difference in β-ray energy. According to this method, P^<32> and Ca^<45>, when existed at the same time in one plant, could be traced independently, individual difference of plants being eliminated. 2. By this separation method, translocation and distribution of P^<32> and Ca^<45> in soy-bean plant were examined, and we found that the translocation rate of "Ca" was slower than that of "P", but "Ca" was translocated, as time elapsed, to the upper leaves. 3. It was concluded, therefore, that distribution and translocation of "P" would be dependent on the metabolic factors, i. e. respiration and photosynthesis. On the other hand, those of "Ca" would be dependent rather on non-metabolic factors such as exchange and diffusion. 4. In the field, the first hunger signs of "N", "P", "K" etc. usually appeared in upper leaves, while those of "Ca", "Fe", "B" etc., in lower leaves. This phenomena was possibly due to the difference of translocation rate in the plant of each nutrient.

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In this paper, the distributions of free oxides in two dry paddy soil profiles are reported. Both soils have developed in flood materials, deposited about eighty years ago, and have become old matured paddy soils. Their parent materials are cherty and rich in gravel. The structures develop well. The levels of ground water are low, and gley horizons are not found within 1 m below the soil surface. The profile-characteristics of these soils are given in Table 1 and mechanical compositions, in Table 2. Free oxides were determined by the Mg-reduction method and the results are given in Table 3 and Fig. 1. Total oxides were determined by the HF-treatment and the results are given in Table 4. The relationships between amounts of total oxides and those of free oxides were calculated from Table 3 and 4,and the results are given in Table 5. From the above results and observations of profiles, the following could be concluded. a) Both the third Horizon in Soil A and the fourth in Soil B are the old furrow slices. b) In Soil A, the new profile develops on the old profile without erasing the characteristics of the old one. c) In Soil B, free iron oxides, leached out of present furrow slice, accumulate mainly in the second horizon, but manganic oxides, in the third (old furrow slice) and the lower ones. Therefore the old profile has been altered in some degree.

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The purpose of our studies is to investigate the reasons why the crop yield in regions where a transferring cultivation between paddy and upland fields is practiced, is always greater than that in a region where the rice plant is the only crop. Samples of soil are four different types; peat, muck, clay and sandy soils as the same in Part 1. Permeability and temperature of soils, content of FeO, base exchange capacity and content of total and organic nitrogen were determined. The following results were obtained. 1) Permeability of the soil in the transferring fields is greater than that in the one crop paddy fields, because the better soil granular structure is made in the transferring cultivation field. Almost no difference of temperature was between two soils, the paddy field and the transferring cultivation field as shown in Table 3. 2) Content of FeO, total, nitrogen and base exchange capacity, in May, are higher in the transferring cultivation field than in the paddy field. Content of easily decomposed organic nitrogen, in July, has the same result. These results are given in Table 2,4,5 and 7. 3) Contents of NO_3-N in May and NH_4-N in July and September were measured. Rate of availability of N to the rice plant in the transferring cultivation field is more or less slower than in the one crop paddy field, but the efficiency of N is higher than in the one crop paddy field. 4) The reason why the yield of rice plant in the transferring cultivation field is greater than the paddy field, will be explained as that primarily physical soil structure is good for the rice plant, and secondarily efficiency of available N becoms higher.

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In reference to increasing the yield of aged paddy soil, we studied the influence of "ARASHI" (drying paddy field soil in summer for upland farm on the rice-yield of next year. In this paper we investigated the difference of chemical and physical properties between the paddy soil and "ARASHI" soil in the low-yield area. The results obtained is as follows : 1) On the Chichibu palaeozoic series, "ARASHI" promoted weathering of aged paddy soil, changing fine sand into clay, and increasing free iron oxide. At the same time, the rotted product in soil humus changed into the true humic acid, forming the silica-humic complex. These products seemed to retard the development of hydrogen sulfide, and to increase the rice-yield. 2) On the Granite, "ARASHI" did not changed chemical and physical properties of aged paddy soil, and did not promoted the humification of soil. Consequently it seemed not to keep the immaturity of soil, and not to increase the rice-yield.

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The authors studied the difference of oxidizing power of seedling roots among thirteen varieties of paddy rice, water-cultured in glass room. Oxidizing power of roots were determined by the method based on precipitation of esculin. Thirteen varieties of paddy rice used were as follows : Norin No. 22,Norin No. 29,Norin No. 37,Mihonishiki, Aichi asahi, Chugoku No. 1,Habutae-mochi, Hokuchu No. 7,Tosan No. 41,Shiga asahi No. 20,Shiga asahi No. 27,Omi asahi, and Yubae. Results obtained were shown in Table 1.

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After heating graular calcium cyanamide with urea or calcium nitrate, we measured its expansion, change in weight and also its hardness. Results were as follows : (1) The weight of sample, which was exposed to the air in a room, increased owing to the absorption of water from the atmosphere, but this sample did not show any great expansion and was considerably hard. (2) When the granular calcium cyanamide with urea was sealed after being heated, it showed a severe expansion and collapsed. In the case, when it contained calcium nitrate, it became rather soft and not seemed to have expanded. (3) The explanation that the expansion by hydration of calcium oxide is cause of collapse of the granular calcium cyanamide, was concluded to be incorrect. (4) Loss of water by heating, was concluded to be the cause of collapse of the granular calcium cyanamide manufactured by wet process.

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The author distinguished three stages in the growth of rice plat, viz., the 1st stage is from the germination to the ear forming, the 2nd stage is from the ear forming to the flworing and the 3rd stage is after flowering. Three stages of growth are chiefly connected with the function of leaves 3/0〜5/0,6/0〜9/0 and 10/0〜12/0 respectively. To make clear the physiological bases of these characteristic functions of leaves, the characteristics of nitrogen metabolism of these leaves are studied first. The present report embodies results of these studies. The following results were obtained from them. 1) The total amount of nitrogen in each leaf increases accompanying with the growth of that leaf, and, after reaching to the maximum value, it decreases. The time when the maximum nitrogen accumulation in a leaf is attained, comes in sequence from lower leaf to upper leaf as indicated in Fig. 4. Periods between the peak of the curve of the nitrogen fluxion of one leaf and that of the next leaf are not constant. Specifically, in leaves 3/0〜5/0 the periods are almost the same; in 6/0〜9/0 nitrogen begins to accumulate from lower leaves first, then to upper ones, but it does not outflow from these leaves until earforming stage. Then the nitrogen in all leaves decreases at the same time and nitrogen accumulates in spikelet and stem simultaneously; in leaves 10/0〜12/0 nitrogen begins to accumulate from lower leaves to upper ones. After the flowering stage nitrogen in these leaves begins to flow out and accumulates in ear synchronously. 2) Translocation quotients of nitrogen (as shown in Table 3) differ by the position of the leaf, In the case 3/0〜5/0 it shows about 50%, in the case of 6/0〜9/0 it shows 70%, and in the case of 10/0〜12/0 it reaches to 75%. 3) In the 1st stage of growth, the nitrogen contents of leaves at upper position are higher than that of lower ones, but in the 2nd stage of growth, nitrogen contents of leaves at any position are almost the same. 4) Leaves 3/0〜5/0 have characteristic connection to tillering. As far as the nitrogen metabolism is concerned, it is not reasonable to consider that a tiller at any position becomes independent receiving its nitrogen supply from the stored in the leaf at the same position. But substances assimilated by a leaf accelerate nitrogen absorption and the nitrogen thus absorbed goes up to the tiller at the same position.

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Four synthetic soil conditioners (VAMA, NPAN, CMC, PVA) were put in the middle layer of soil in the lysimeter 1 lb. in weight. The lysimeters were irrigated, and the drainage in them were estimated continuously for 60 days. 1. VAMA and HPAN were most effective to prevent the soil from its leaking perfectly, when used 2 g per 40 cm^2. (Fig. 2〜3) 2. CMC was less effective than VAMA, and PVA could not lessen leaking. (Fig. 4〜5) 3. Ca(OH)_2,CaCO_3,Al_2(SO_4)_3,FeCl_3 and two sufactants were applied. But no influence of these materials was on the preventing effect of conditioners. (Fig. 6〜8) 4. Soil conditioners were put in the upper parts of soils, and their preventing effect on leaking were observed. But, in this case, they were less effective than in the case when they were spread in a thin layer. 5. The soil was mixed with conditioners, dried at 40〜50℃, and then, irrigated. But, in this case the preventing effect of conditioners on leaking was not observed.

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The distribution of radiophosphorus absorbed in the young rape plants, under the photoperiodic treatment, was investigated. In this experiment, the one group was cultured with normal solution and the other group, with low level phosphorus content solution. Under the long day treatment, formation of flower primordia was observed only in normal solution group, but the relation between the flower initiation and the phosphorus translocation was obscure. Under the long day treatment, in both groups, accumulation of phosphorus was observed at the tops of plant, but, under the short day treatment, disturbance of phosphorus distribution occured. In the low level phosphorus group, specific activity of roots was lower than that of stem. The details of results were shown in Table 2 and Fig. 1.

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