In the previous reports it was shown that the nutrients uptake by plant roots was largely dependent on their metabolic activity, and that in view of the linkage in the metabolic cycle its degree decreased in the order K_2O, P_2O_5>SiO_2,Br, SO_3>NH_4,MnO>MgO, CaO; K_2O and P_2O_5 linking most directly in the cycle. In this report the uptake of K_2O, P_2O_5 and NH_4-N by barley seedlings as influenced by 2,4-Dinitrophenol (DNP) was studied. DNP is well qualified as one of the agents which break up the link between substantial and energetical metabolisms by inhibiting oxidative phosphorylation. Barley seedlings were grown by customary water culture technique and treated with DNP or NaN_3. The uptake of K_2O, P_2O_5,NH_4-N was calculated from the residual nutrients in the culture solution and the oxygen uptake by WARBURG'S manometric technique. The relationships between the oxygen uptake of the roots of barley seedlings and concentration of inhibitors were shown in Table 1 and Fig. 1. It is evident that 10^<-4> Mol. DNP increased the oxygen uptake by barley roots as contrasted to the remarkable depression through NaN_3. Moreover, this effect normally continued during the expected measurement and treatment, indicating that this normality of the inhibitor is suitable for the aforementioned purpose within the experimental conditions (cf. Fig. 2 & 3). The uptake of NH_4-N, P_2O_5 and K_2O by barley seedlings as influenced by l0^<-4> Mol DNP and 10^<-2> Mol NaN_3 were shown in Table 2 and Fig. 4. In either case P_2O_5 excreted out, whereas K_2O excreted out by NaN_3 but its uptake ceased by DNP. The uptake of NH_4-N was appreciably depressed by NaN_3 but very slightly by DNP. The result was discussed on the basis of the characteristic different behaviors of the pertinent inhibitors. Assume that P_2O_5 accumulation is primarily and directly linked with the formation of energy rich phosphate through oxidative phosphorylation, there is no wonder that DNP and NaN_3 decidedly and equally inhibited P_2O_5 uptake. The excretion of phosphate may be due to the superior counter reaction from organic phosphate to inorganic phosphate. K_2O uptake most probably proceeds through the combination of K at the specific sites of certain acceptor by the expense of energy derived from energy rich phosphate bonding such as ATP. NaN_3 inhibits not only this process but also most likely the formation of this acceptor, whereas DNP seems to be almost indifferent from the latter substantial process, resulting in a different inhibition by the two inhibitors. The first step of NH_4-N uptake is believed to be the combination of NH_4^+ with certain Keto-acid, and the next step the formation of amide as a result of condensation of the formed amino-acid with NH_4^+. Only the latter process repuires energy from the energy rich phosphate bonding such as ATP. Therefore, NaN_3 most probably inhibits both processes and DNP the latter only, resulting in a different inhibition as shown in the Table. Moreover, the slight inhibition in general of NH_4-N as compared to P_2O_5 would be attributed to the slower counter reration in the uptake of N as compared to P.

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Of the two areas, Suwa-lake and Tenryu-vally, in Nagano Pref., soil survey was made. Around the lake there were observed Half-bog soil, Meadow soils (including River-bed type) and Gray lowland soil; and, in the valley, Brown forest soil and Brown lowland soils (including River-bed type) (see Table 1-8 and Maps). From the results of physical and chemical analyses, the following inclinations were found (see Table 9-12). 1) Of Half-bog soil, subsoil was muck, of much C, and rich in humus. When incubated, the soil produced considerable amount of ammonium-N. 2) Compared to normal Meadow soil and Gray lowland soil, Meadow soil of river-bed type was very poor in its finer component; consequently, it had low water holding capacity. 3) Brown forest soil in surveyed area was of poor base status under the forest cover (refer to soils, 43,44,45,47 in Table 12); and it seemed to be increased in its saturation degree of CaO by the cultivation for farm (refer to soils, 20,21,22; and 33,34,35 in Table 12). 4) Brown lowland soil, somewhat artificially made by irrigation, had a tendency to accumulate its Ca content in G horizon. (refer to Soils, 30,31,& 32 in Table 12). In the case of Brown lowland soil of River-bed type, saturation degree of CaO seemed to be decreased in subsoil. 5) By irrigation, the soils of upland farm seemed to increase its finer parts and to decrease its saturation degree of CaO (refer to soils, 23 & 24 in Table 12). In order to increase the productivity of surveyed area, the following remarks could be paid for each soil type. 1) Of Suwa-lake area. According to the public plan, the whole area is fixed to be drained. When drained, Half-bog soil area, first of all, is expected to be suffered from an extraordinal increase of available N, originated from the decomposition of organic matter in the soil. This suffering is to be avoided by the application of N in properly reduced amount and also by the addition of phosphate. Among the Meadow soil area, the area occupied by that of River-bed type must care for its being easily leached. Some considerations such as soil covering with proper fertilization must be paid to overcome this leaching. Properly drained, Gray lowland soil area is expected to turn out as profitable farm of double crop a year and to be in response to heavy fertilization. 2) Of Tenryu-valley area. The irrigation is planned to be more widely applied in this area. The soils, so irrigated, have a tendency to be leached. Care must be paid for maintaining the nutrients in suitable amount by proper fertilization; especially for Brown lowland soil of River-bed type.

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Fractionation of organic phosphorus in soil and the properties of the easily dephosphorylable fraction were investigated this time. The results may be summarized as follows : 1. The BOWER'S method, which was considered to fractionate organic phosphorus, extracted from soil by 2% NaOH, into two types, phytin and nucleic acid, was proved by the authors not to be successful in some soils of this experiment (Table 1). 2. "Nucleotide" precipitation, isolated by the method of DYER using 4% NH_4OH for extraction, was more resistant to the dephosphorylation by rice bran enzyme than the filtrate from the above precipitation (Table 2 and Fig. 2). 3. Organic phosphorus in the Ca filtrate, extracting soil with 2 volumes of 2% NaOH at 60°, was dephosphorylated by the action of alkali phosphatase and easily oxidised by alkaline hypobromite, thus the phosphorus in this filtrate was presumed to be of a nucleic acid-like form (Table 3 and Fig. 3〜4).

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In this paper the authors studied the differences in chemical and physical properties of the Hino-soils (Shiga prefecture). These soils were from various fields as crop plant field planted with or without perennial grasses (Leguminous and Others) and uncultivated field. By chemical methods, pH, CaCO_3,exchange acidity, exchangeable calcium, C/N ratio, iso-electric point, sedimentation volume in water amount of soluble aluminum, humus of various types, effects of drying soil on the amount of ammonium, were determined, and by physical methods, volume weight, porosity, aggregate factor, limit of plasticity, max. moisture capacity, with these soils. The results were summarized as follows : 1) Chemical properties (Table 1〜5) : The most characteristic difference was found between the top-soil (2nd-layer) of the field with grass and that (1st-layer) of the field without grass : that is, in the former CaCO_3 evidently remained much, but in the latter CaCO_3 was leached out, base exchange properties and types of humus were better in the former than in the latter and drying effects on the amount of ammonium were less in the former than in the latter. From these results, the top-soil (2nd-layer) of the field with grass was alike to the soil of the chernozem type, and the chemical properties of this layer were better than the top-soil (1st-layer) of the field with grass and also that (1st layer) of the field without grass. 2) Physical properties (Table 6,7) : of the top-soil (2nd-layer) of the field with grass the aggregate factor was 64.6 and the max. moisture capacity (mass) was 38.2 : this layer contsituted the good aggregated structure, and its colloid was thought to be changed qualitatively. Of the top-soil (1st-layer) of the field with grass the aggregate factor was 37.7 and the max. moisture capacity (mass) was 31.3; its aggregated structure was broken down and connverted into the single grain structure owing to the reason that the soil was not long disturbed by the ploughing while the field was planted with grass. Of the field without grass, the aggregate factor was 39.1 and the max. moisture capacity (mass) was 30.0; its aggregated structure was broken down, and its physical properties were changed to be unexpectedly bad. The top-soil (2nd-layer) of the uncultivated soil constituted the fairly aggregated structure, though the chemical properties were bad. 3) By means of the method to cultivate the perennial grass on the field, where the soil structure had turned out bad, the structure were improved, and brought to have good chemical properties. From these facts, we could recognize the possibility to keep the field soil always in a young stage against the weathering action.

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Barley plants were grown in a series of nutrient solutions in which one of the microelements was eliminated, and the deficiency symptoms and the growth rate were examined. The changes of IAA oxidase activity were estimated on the root tissues of these plants, and the results obtained are summarized as follows : 1) The IAA oxidase activities of each root tissue of iron, manganese, zinc, and boron deficient plants were almost the same as that of the control, although their growth had been depressed. 2) In the copper and molybdenum deficient plants the IAA oxidase activity of the root was very weak, being only 20 and 8% respectively compared with that in the complete nutrients. 3) By the addition of copper to the plants deficient in it, the IAA oxidase activity of their roots was restored almost completely to the level of the control plants within five days, while in the case of molydenum no restoration was recognized. 4) From these results it may be supposed that the IAA oxidase is a copper protein and that molybdenum plays an important role in the synthetic processes of this enzyme. The details of this research is published in English on Tohoku Journal of Agricultural Research, 5,47 (1954) c/o Faculty of Agr., Tohoku University, Sendai.

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Rape and sesame plants were cultivated with P^<32> containing culture solution and the distribution of P^<32> in the various parts of plants were investigated at each stage of the plant growth. In the rape experiments, the radioactive solution was supplied to the crops during the period from Jan. 1 (112th day after sowing) to Jan. 7. After the treatment, the crops were cultivated by the standard culture solution containing nonradioactive phosphorus. On each of the following days, 8/Jan., 5/Feb., 4/Mar., 1/Apr., 22/Apr., the plants were sampled and estimated their total phosphorus and the radioactivity. In the sesame experiments, the radioactive solution was supplied to the crops during the period from July 30 (40th day after sowing) to Aug. 5. After the treatment, crops were sampled every week and estimation were performed. The results are shown in the Tables 1,2 and Figs. 1-4.

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Haraizumi Village lies 6 miles north-west of Kakegawa City, situated about the central part of Shizuoka Prefecture, and has a whole area of 36.65 km^2 or 9,038.99 acres, 86%, the most part of which is occupied by steep mountains. Of the area, the most part is forest lands covering 7,773.39 acres, and the rest is farm land, 396.86 acres. Soil types and soil kinds Soil types, prevailing on surveyed area, numbered 3 as follows : I : Zonal Soil types (Vegetation soil types), Brown forest soils II. Azonal soil types (Mountain soil types) Mountain soils III. Intrazonal soil types (Ground water soil types) Meadow soil, river-bed type Each soil type in above list, is classified into 7 soil kinds, after its morphological character. Some models of profiles of each soil type, and each soil kind, are shown as follows : (1) Brown forest soils (Soil kind 1) Locality-Tamma, Haraizumi Village Relief-Hillside slope land, Slope 30° NW, 310m above sea level Parent material-Weathered shale Utilization-Mixed forests, Cryptomeria (Japanese cedar) and Cypress (Japanese cypress) Soil profile-A_<00> A thin layer of needles, mostly undecomposed, about 0 to 0.7cm thick A_0 Raw humus layer of black brown, partly disintegrated, loose, pH 6.5,0 to 2.0 cm thick A 0 to 8 cm, black brown loam, rich in humus, granular, many roots pH 6.5 B_1 8 to 49 cm, dark brown loam, with some humus, comparatively, granular tubular, many roots, pH 6.6 B_2 49 to 66 cm, brown clay loam, nutty, weakly tubular, including some roots, compact pH 6. 6 B_3-C 66 - cm, brown clay loam, with some gravels, compact, pH 6.6 (Soil kind 2) Locality-Tamma, Haraizumi Village Relief-Hillside slope land, Slope 28° NW, 300m above sea level Parent material-Weathered shale Utilization-Tea field Soil profile-A 0 to 10 cm, black brown loam, rich In humus, granular, pH 6.5 B_1 10 to 45 cm, dark brown loam, with some humus, comparatively, granular, pH 6.4 B_2 45 to 68 cm, brown clay loam, nutty, compact, pH 6.6 B_3-C 68-cm, brown clay loam, with some gravels, compact, pH 6.6 (2) Mountain soils (Soil kind 3) Locality-Kuromata, Haraizumi Village Relief-Steep mountain side, slope 40° NW, 400 m, above sea level Parent material-Mixture of weathered clayslate and other rocks Utilization-Mixed forests, Cryptomeria (Japanese cedar) and Cypress (Japanese cypress) Soil profile-A_<00> A thin layer of needles, mostl yundecomposed about 0 to 0.8 cm thick A_0 Raw humus layer of black brown, partly disintegrated, loose, pH 6.5,0 to 2.3 cm thick A 0 to 8 cm, black brown loam, rich in humus, granular, nutty at the boundary of two horizons, A and C, many roots, pH 6.6 C 8-cm, brown loam, rich in gravel and detritus, tubular, including some roots, compact, pH 6.6 (Soil kind 4) Locality-Kuromata, Haraizumi Village Relief-Steep mountain side, slope 40° NW, 400 m, above sea level Parent material-Mixture of weathered clayslate and other rocks Utilization-Mixed forests, Cryptomeria (Japanese cedar) and Cypress (Japanese cypress) Soil profile-A_<00> A thin layer of needles, mostly undecomposed, about 0 to 0.8cm thick A_0-A 0 to 9 cm, black brown loam, rich in humus, with some humus, mycelia were found at the border two horizons, A_<00> and A_0-A, comparatively granualr, many, roots, nutty at the lower part of the horizon A_0-A, pH 6.6 C 9-cm, blown clay loam, rich in gravel and detritus, weakly tubular, compact, including some roots, pH 6.6 (Soil kind 5) Locality-Hagima, Haraizumi Village Relief-Steep mountain side, slope 42° SW, 320m, above see level Parent material-Mixture of weathered sand-stone and other rocks Utilization-Mixed forest, Red pine and Oak (Nara and Kashi) Soil profile-A_<00> Loose leaves and pine needles, mostly undecomposed, about 0 to 0.7cm thick A_0-A 0 to 2.5 cm, black brown loam, rich in humus, with some raw humus, with mycelia including some roots, pH 6.5 C 2. 5-cm, brown loam, with some gravels and detritus, including

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We have compared the manurial effects of magnesian fertilizers for barley plants on magnesium-deficient soils. We have learned that magnesium functioned as a carrier of phosphate and was very effective for the grain productivity of barley plants. And again we have ascertained that fused phosphate and magnesian limestone were very effective to eliminate magnesium deficiencies in barley plants and their manurial effects were remarkably excellent on these soils.

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