From the results of experiment, it may be concluded that the effect of Bentonite on the growth and yield of crop varies with the menthods of applying to the soil. Also it may be presumed that the action of Bentonite depends on both its base exchange capacity and the density and kind of fertilizers used.

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Paper-chromatographic analysis was done on the sugar contained in embryo and endosperm of the lowland rice seed, and of each of the youngest seedling and its endosperm, i. e., Norin No. 41 (translucent grain) which requires more oxygen for germination and Hikotaro-mochi(non-translucent grain) which requires less, both being germinated at 30°C on the water blotted paper, in water 5 cm depth, and in water 5 cm depth and vacuumed by rotary pump. Sugars detected in this experiment were raffinose, sucrose, glucose, fructose and two unidentified sugar-like substances. Raffinose was disappeared as germination progressed, but galactose to be produced by its hydrolysis was not found. Sucrose was always detected in seeds regardless of the different germinating conditions. It was considered that hexoses were synthesized into sucrose as a precusor-like type or a translocating type. Maltose which should be naturally produced from starch was not fund. It may be produced from starch by amylase in vivo, without regards the weak intensity of its reaction, because pH values of cell saps in the embryo and the endosperm of two kinds of seeds are greater than optimum value in vitro. Hexose were found in each of two kinds of seeds at 4-8 hours after the imbedding on the water blotted paper or by submerging in the water of 5 cm depth, but these were found only in the endosperm during 4-20 hours in the anaerobic condition while in embryo and endosperm it takes 24 hours. From above results, as disclosed dy DASTUR and DESAI (1935), enzymic activities in the germination were pormoted by a successive supply of oxygen, while these were inhibited under the anaerobic condition, particularly invertase was concerned. In this connection, it is considered that hydrolysis of sucrose by invertase is the most important factor for the germination and the suceeding growth of the seedling.

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Using seeds of three varieties both upland and lowland rice, non-volatile organic acids occurred in germinating stage under three germinating conditions on the water blotted paper, in water (Subdivided to 0.6 cm and 5 cm depth) and in vacuum were examined by paper-chromatography. 1) In the ungerminated seeds, oxalic, citric and malic acids were found in both embryo and endosperm of upland and lowland rice seeds, however, glycollic, α-ketoglutaric, lactic, succinic and fumaric acids were found with the passage of germination time. 2) From these facts, it is suppposed that the Krebs cycle occurs in germinating stage of rice seeds, both embryo and endosperm. 3) In embryo, the amount of malic acid is larger than citric acid, while citric acid is larger than malic acid in endosperm, however in embryo, in vacuum, citric acid is more abundant than malic acid before 36 hours of germination time, and at the 72 hours, for the first time, malic acid became much more than citric acid. 4. In vacuum, both sort and quantity of acids were less than in two other germinating conditions. 5. No remarkable differences were found between upland and lowland rice Seeds, and Uruchi translucent grain) and Mochi (non-translucent) types.

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Responses of the growth grain-yield and yield-constitutional factors to the temperature and its daily range were examined by subjecting rice-plants to different combinations of controlled day and night temperatures for 15 days in different growth stages. Optimum day and night temperatures for increasing the grain-yield and its constitutional factors and for advancing the date of heading were pointed out in different growth-stages, as shown in Table 1, while the optimum ranges of daily temperature could hardly be found. Some supplementary explanations are given as follows. (1) A high day temperature (36°C) and a low night temperature (16°C) are favourable for branching out of tillers, while a high day and night temperature (31°C) is suitable for development of tillers. Consequently, the day temperature of 31°C and the night temperature of 21°C have been found to be optimum for increasing the number of panicles. (2) A high day temperature is favourable for vigorous differentiation of spikelets and rachis branches, while the night temperature seems to have a much smaller effect on it than the day temperature. (3) A high day temperature (36°C) and a little low night temperature (21°C) are optimal for preventing the regeneration of spikelets and rachis branches. (4) Optimum day and night temperatures for ripening of grains are almost the same as those reported in the previous paper (Vol. XXV. No.4). (5) It is worthy of notice that a rather low night temperature in every stage of growth is necessary for favourable grain production, except the tillering stage and the late ripening stage. (6) It is also of great interest that the date of heading is clearly advanced by a low night temperature (16°C) at the tillering stage.

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[in Japanese]

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In this report, the active duration of phosphorylase within the ripening kernel was examined, when rice plants were placed under the cool temperature. Upon experiments, two glass rooms, the cool glass room at 17°C constant for the treatment and the glass room without air-conditioning for the control, were used. Rice plants, variety Norin No. 29, were previously cultured in pots in the field. Flowers which bloomed on the 7th of September (1956) were labelled. After three days, rice plants were placed in two glass rooms separately. Enzyme preparations were made from time to time from the kernel at the various stages of ripening, which had been developed from only the labelled flowers. The method for the measurement of phosphorylase activity was the same as the case of the previous work. As shown in Fig. 1, it was found that the active duration of the starch phosphorylase of rice plants which were placed in the cool glass room was considerably prolonged further than the control, without any lowering in enzyme activity of the corresponding age of kernel.

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The experiments on the influence of periodical and continuous drainage, and periodical circulation of irrigation water on the growth of rice were made using artificial paddy soils, during 2 years 1956-57. The results obtained were as follows :-(1) The growth of leaves and stems showed no difference between periodical circulation drainage and control, but it was less in continuous drainage than in control. (2) Circulation of irrigation water and drainage magnified roots-crowd, especially, periodical circulation and drainage increased number, dry weight, depth and vitality of roots. (3) The yields in the drainage plot was decreasd partly by the loss of nutrients in the soil, but the yeild was increased in the periodical circulation by about 8 % than that of the control, accompanied with vigorous growth of roots. (4) Summarily, circulation of irrigation water is useful in oxygen supply to roots-crowd, increase of soil temperature preventing loss of various nutrients, exclude of injurious gases, economy of water and beneficial for rice plants growing in submerged paddy field, especially in leakage soils, and Akiochi soils.

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The experiments were made to know the relation between the rate of transpiration and distribution of sweet potato varieties. 1) Rate of transpiration in NORIN No.1 and OKINAWA No. 100, varieties cultivated in the eastern Japan, increases at 24°-26°C, but shows decrease at 27-28°C, while that of NORIN No.2, GOKOKU, and SHICHIFUKU, these are grown in the south-western Japan, increases at 27-28°C and decreases at 24-26°C 2) The response of transpiration for temperature is supposed to have some bearing on the geo-graphical distribution of sweet potato varieties.

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In this experiment, 48 varieties of 17 species leguminous crops were used as materials. Each crops were planted in various experimental conditions, varying in amount of nitrogen spplied, light intensity and method of inoculation, ie, the artifitial inoculation in soil cultur, or the natural inoculation in field cultur and the guartz sand cultur in different inoculate of nodule bacteria, in the suitable season for each crop. The external and internal observations were made on: 1) the location of nodule formation on root system, the nodule numbers and weights. 2) the site of nodule origin and the developmental prcocess of nodule formation with the histological methods. during from the germinating stage of host plants to the flowering stage at various intervals of time. The data obtained with the different varieties of same species are not tabulated separately in this paper. The results obtained are as follows: (1) The classification on the basis of the location of nodule formation on root systems. I-A : The primary and lateral roots type: the nodule formation was found on the primary and all the lateral rootlets and the nodule's size and number were most large in the basal portion as compared with the apical portion in same root. I-B : The lateral roots type: the nodule formation occurred only on the lateral roots, even though the host plants were growing under widely different conditions, and the graduation of nodule formation in the same root are identical with I-A type. (2) The classification on the basis of the site of the first infection cell in host tissues. II-A : the outer -layers in primary cortex type: the infection is limited to the outer layers in primary cortex ; endodermis, pricycles and central steles of the root are not directly concerned in their formation other than in the production of the vascular system necessary in the later stage of nodule development. the site of penetration of nodule bacteria into host tissues and of formation of the first infection cell have not correlated with the structur of central stele in roots, therefore, the location of nodules on root were at randam in the external view. II-B the inner-layers in primary cortex type : the nodules have originated by division of the parenchymatous cells in the inner layer of primary cortex in the host plant, usually opposite protoxylem points. for that reason, the location of nodule formation on root were limited in under lyning opposite the prot. xylem point. II-C The axil of lateral root type: the origin of nodules is in pericycle cells adjacent and in juxtaposition to the protoxylem strand from which a rootlet had emerged. therefore, All nodules were located in rootlet axil. In the peanut, this arrengement was conspicuous since the root system of this species consists of a central taproot, along which lateral roots arise in an orderly alignment of four vertical rows, owing to the tetrarck pattern of the xylem. This classification have not correlated with the arc pattern of host roots, the apigeal or hypogeal on germinating stage of host crops and the numbers of cell layers in primary cortex of host, but the good agreement was obtained between the results of this experiment and the cross-inoculation groups on nodule bacteria.

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In the previous paper, the author classified seventeen species of Leguminous, crops into three types according to the initial position of the nodule formation. namely, II-A. type; nodule originates in the outer layers in primary cortex. II-B type; in the inner layres of primarly cortex, and II-C type; the axil of lateral root. The present experiment was carrid out to clarify the relation between the site of first infection cells in different types and the physiological differentiation of host tissues as well as the fermentative characters of each nodule bacteria on the cultural mediums, especiallly, the minimum amount of carbohydrates required for the maximum growth of bacterias. The results are as follows. (1) The relation between the physiological differentiation or the gradients in the primary bodies of host tissues and the location of the first infection cell in host tissues. The distributive pattern of reducing sugars, protein and other nitrogen compounds, and fatty matters in the primary cortex and the pericycle was sames in all plants investigated. The primary cortex cosists with undifferentiated primary parenchyma cells and the cortical cells are identical in general histological appearance but the physiological differentiations were observed within the primary cortex. In general, the reactions of Fehling's solution and Ozazon method for reducing sugars, Bensly's Millon and Ninhydrin reaction by Berg's; for the protein and nitrogen compounds, Sudan Black Alcohol method for fatty matters were stronger at the inner layers of primarly cortex, especially, at the opposite side of the protoxylem points with a progressive decrease towards the outer layer. This results indicated that the nodule formation in II-A type plants took place at where reaction of reducing sugars was most week in primary cortex, in II-B type plants it took place at where the stronger reaction of reducing sugars was shown and in II-C type plants at the pericycl cell showing the stronger reaction for reducing sugars. (2) The relation betweem the sugar requirement of nodule bacterias and the location of the first infection cell in host tissues. The nodule bacterias of different types differs with the minimum level of sugars in the cultural mediums. The minimum concentrations of sugars in AO medium (M. R. N. RAGGIO, 1958) with manntol as carbon source for each bacterias are as follows, 0.01∼0.02 gr/l for Rhizobium Japonicum (II-A type), 0.2∼0.4 g/l for R. Leguminosarum (II-B type), and 0.1∼0.2 g/l for R. Sp (II-C type) respectively.

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1) In plants of less resistant to acidity leaves are rich in Ca% than root, stem and leaf sheath. 2) Ca% in stem and leaf-sheath showed highly negative correlation with the tolerance of crops to soil acidity when extracted by acetie-acid ; and it showed correlation with the amount of pectic-acid % or absorptive power of cytoplasmic protein. 3) In the root of crops, Ca% was apt to be influenced easily by varying Ca concentration or pH-value of the solution. In the less resisting plants, Ca% in acetic-acid generally decreased when cultivated in acidic solution, and this response come also from the character of cytoplasmic protein; These results may be due to the fact that, in less-resisting plants, the decrease of pH value causes the decrease of negative charge in protein and therefore Ca becomes less absorbable and is apt to be released easily. 4) In the crops whose lime requirements are large, their cytoplasmic proteins have high Ca-absorbability and may have propably large negative charge.

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1) Length of top-internode of a culm was influenced by the amounts of top-dressing of nitrogen fertilizers at the stage of flag-leaf emergence. 2) Shortage of nutrients caused by cutting-off the roots or all leaf-blades at the above-mentioned periods accerelates shortening of the length of top-internode. Even in that case, top-dressing of nitrogen makes its shortening less. 3) Numbers of lower sterile spikelets were decreased, whenever the conditions which make the length of top-internode longer are given. The relation is shown in Fig. 1, with the case of var, Kogenmugi. 4) As a results of observations on the developmental process of each spikelets in ear, it is indicated that number of spikelets capable of ripening is determined during 15 to 5 days before the heading, and at the same time elongation of top-internode takes place. 5) A high correlation was obtained between the length of top-internode of a culm and the number of sterile spikelets which determines numbers of grain per ear.

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1. The number of tillers synchronously developed from one root becomes less than the theoretical number, after the growth of [5] of the first tillering rank, and the cumulative tillers' number diverges from the theoretical value, showing a curve represented by the equation; S=an²+bn+c and S=an+b. (fig. 1) 2. It is caused by decrease of the growing rate, delay of emergence of tillers and increase of tillering ranks' number. 3. In the system of tillering, the stems show the following appearance of death: original stem and its early neighbourings are perfectly died and tillers outside of that are dead in half, then top die, and the most outside stems are normal. As to the length of stems, the original and neighbouring ones and the most outside stems are shortest; and stems inside of that are intermediate dividing two ways, and about the center of that system, there are longest ones. (fig. 2) 4. We can observe the distinct quality of synchronized tillers in appearance of death and length.

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Fruiting is not expected with the inperfectly grown pistil. In buckwheat "day length" is highly influencial in inducing the retarded growth of pistil. Retardation of growth is serious in proportion to day length during the progress of its growth, such as vegetable period and differentiation of the flower-bud. It is interesting that there is varietal difference in the retardation of growth of pistil as influenced by the day-length.

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In the previous paper, high correlation between the distribution of oil glands and the percentage yield of essential oil was pointed out. The present study was carried out in 1956 and 1957 in order to see the seasonal fluctuations in both the distribution of oil glands and the percentage yield of oil. P. roseum Willd. (biennial) was used. The results are summarized as follows : 1) The seasonal fluctuation in the distribution of oil glands shows a similar tendency to that of the percentage yield of essential oil, with respect to the position of leaves on the stem (Figs. 1 & 2). The percentage of oil increases gradually from June (spring harvest), reaches a maximum in August (summer harvest) and then decreases somewhatin September. But it increases again in October (autumn harvest), and thereafter decreases remarkably. During the period of a maximum yield in summer, the production of essential oil in young leaves in remarkable. 2) The similar trend in also shown in the percentage of essential oil of fresh plant material, which consists fo leaves and stalks (Table 1). 3) Although the correlation between the number of oil glands and the percentage of essential oil is very high in every season, the regression coefficient is the highest in August and low in October and June (Fig. 3). This suggests that the secretory activity of oil gland reaches a maximum in August. 4) It is concluded that the seasonal fluctuation of the percentage of oil is ascribed to that of both the distribution and the secretory activity of oil gland.

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It seems that the percentage yield of essential oil varies greatly according to climatic conditions. The fine weather during the harvest time seems to bring a good yield, whereas rainy or cluody weather lowers the yield. After a stormy weather, the yield becomes very poor. The experiments were undertaken from September to November in 1957 to determine the daily fluctuation of percentage yield of essential oil in P. roseum Willd. Results are shown in Fig. 1 and Table 1. The percentage fo essential oil is highest towards the evening but lowest in the early morning. The essential oil content of the leaves depends mainly upon weather conditions, ………the high temperature or the intensive sunshine greatly influences the yield of essential oil. When the temperature rises, the percentage yield of oil increases remarkably. But, in cloudy or rainy day, no marked daily fluctuation in oil content can be noticed. Moist conditions lowers the percentage yield of oil. The amount of water contained in the plant tissue is almost constant during the day time. It is concluded that daily fluctuation of percentage yield of essential oil must be caused by the change in the secretory activity of oil glands, because distribution of oil glands in the leaves is not changed.

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In connection with studies on abortive seed formation in Azuki-beans, several physiological studies were made on pollen germination. The artificial medium contains 1% agar, 30% sucrosc (Table 1) and pH 5.4∼5.8 (Fig. 1) was almost suitable for pollen germination. The pollen germinability reached to the peak towards anther-dehiscence and then decreased gradually in different stages of anthesis. The optimum temperature of pollen germination was near at 25°C, and the germinability decreased especially on Fohn weather. The preservation of pollen grains was favourable in 7°C and 20% humidity.

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