1. In sand culture of 3-year-old Delaware grape vines supplied with proper level of nitrogen (80 ppm), the effects of varying levels of phosphoric acid (80, 40, 20 and 0 ppm) and potassium (160, 80, 40 and 0 ppm) on yield and quality of fruit were observed. The treatments were applied at two stages of shoot growth (from early April to late June) and fruit growth (from early July to late August).
2. A high level of phosphoric acid (80 ppm) when supplied at the stage of shoot growth, gave greatly improved yield and better quality of fruit, by increasing the degree of color and sugar content, and by lowering the acidity. The same application made at the stage of fruit growth, gave an increase in yield, but a reduction in the degree of color and sugar content, and no striking effect on the acidity.
3. On the contrary, high levels of potassium (160 ppm and 80 ppm) applied at the stage of shoot growth produced no significant influence on the yield and quality of fruit except for an extreme increase of acidity. But, when applied at the stage of fruit growth, high levels of potassium improved both the yield and degree of color.
4. Moreover, in the potassium treatments, when the number of berries per vine in each plot was restricted equally at the beginning of fruit growth stage, the high level plots gave better quality of fruit including the color, sugar content, and acidity than the low level plots.
5. Thus, this experiment seems to show that phosphoric acid needs to be applied more abundantly at the stage of shoot growth than at the stage of fruit growth, while for potassium the reverse is true, that is, smaller applications are needed at the stage of shoot growth and larger ones at the stage of fruit growth.
6. Besides, it was observed that the higher the level of phosphoric acid given at the stage of shoot growth, the greater the number of flowers per vine, and the number of seeds per berry. The higher the level of potassium supplied at the stage of shoot growth, the greater the amount of potassium and the lower the quantity of both nitrogen and phosphoric acid contained in the leaves at the end of the stage, resulting in the shorter shoot elongation.
7. And the leaf analysis made at harvesting time, indicated that the higher the level of phosphoric acid or potassium given at any stage of shoot or fruit growth, the greater the content of those elements in the leaves. This, however, showed no distinct antagonism against the other elements, probably due to the difference in fruit load in the plots.

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This experiment was carried out to study the effect of methods of treating soil in planting hole on the current year growth of young chestnut trees planted in the hole. Large planting holes of 120cm in diameter and 90cm in depth were dug and: refilled with the soil in the following procedure.
Plot 1. Each layer of soil was returned to its original position: surface soil to the top layer, subsoil to the bottom.
Plot 2. The surface soil was placed in the bottom of the hole and the subsoil in the top.
Plot 3. The hole was refilled with the mixture of surface soil and subsoil.
Plot 4. The hole was refilled with the surface soil only.
Plot 5. Large holes were not dug. Young trees were set in the small holes just large enough for planting the trees.
A one-year-old chestnut tree (var. Ginyose, a leading variety in Japan) grafted on free stock was planted in the center of each hole.
The measurement at the end of current growing season revealed that trunk circumference was largest in Plot 1, followed by Plot 4 and 5, 3 and 2 in the order. It continued to increase until later in the season in Plot 1 and 4 than in the other plots. Total shoot length was longest in Plot 1 and 4, medium in Plot 3 and shortest in Plot 2 and 5. Shoot elongation ceased earliest in Plot 2 and 3, later in Plot 4 and 5, and did not stop by late fall in Plot 1. The top fresh weight after leaf fall was heaviest in Plot 1, followed by Plot 4, 5, 3, and 2 in the order.
One representative tree each from Plot 1, 2 and 3, respectively was excavated to observe its root system. Roots in Plot 1 penetrated to the deepest layer, and roots in Plot 3 to the shallowest, while there was no significant difference in the extent of lateral spread of root system among the plots.
Leaf samples were collected four times during the growing season for leaf analyses. Little difference was found in N and P contents among the plots, but a positive correlation was found between K content in the leaves and growth.
Chemical properties of each layer of the soil were determined, and porosity of the soil in the planting holes was measured.
From these data it is suggested that the growth of young chestnut trees was affected not only by the physical properties of soil but also by its chemical properties, and poor growth in the current year in the plots, where subsoil was brought to the top layer, might be due to the poor fertility of that layer.

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The effects of fertilizing in late autumn on the number of flowers and the growth of shoots were investigated with Satsuma orange and lemon trees from 1949 to 1956.
1. Fertilizer application in late autumn showed tendency to increase the number of flowers and shoots the next spring, but the effect was different depending on the nutritional conditions of the trees. Generally speaking, the increase in number of flowers was not remarkable.
2. Among fertilizers, nitrogen was most effective in increasing the number of flowers. The addition of phosphorus and potash did not have a marked effect. The application of phosphorus and potash without nitrogen was almost ineffective.
3. The effect of urea spray in late autumn seemed to be faster and greater than that of soil dressing.

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1. Growth response of citrus seedlings to various soil temperatures in summer was observed with 8 varieties planted in soil contained in glass pots (1, 800 ml). The glass pots were kept in the glass room in the thermostatic boxes heated electrically (Fig. 1) for 36 or 45 days during the period from April to August, 1954. The soil temperatures in the pots were maintained at 20_??_22°C, 30_??_32°C and 40_??_42°C. Citrus Natsudaidai, C. intermedia and C. grandis var. Hogen, heat resistant varieties, showed their maximum growth rates at 30_??_32°C, while C. junos, Poncirus trifoliata, C. Tachibana and C. Tamurana at 20_??_22°C, and C. leiocarpa at 2_??_32°C (Table 1, Fig. 2, 3). But the heat resistant varieties showed a better growth even at 20_??_22°C than the rest. At 40_??_42°C, the former varieties grew only slightly, but the latter scarecely. These results seem to have shown that C. Natsudaidai, C. intermedia and C. grandis var. Hogen are most suitable as root-stock followed by C. junos in the summer soil in Kochi, where the soil temperature reaches 24_??_31°C at 0_??_30cm in depth in summer.
2. The roots of citrus seedlings of 10 varieties were soaked in the water baths at 5 and 10°C from February 7 to March 6, 1955. The results observed are shown in Fig. 6. Growth response of citrus seedlings to various soil temperatures in winter was observed with 12 varieties planted in soil contained in glass pots (500 ml). These glass pots were kept in field in the thermostatic boxes from December 23, 1956 to April 30, 1957. The soil temperature of the high heated plot was maintained at 18_??_23°C, those of the low heated and nonheated plots at 9_??_15°C and 3_??_13°C, respectively. The results observed are shown in Fig. 4, 5, 6 and 7.
3. The seedling roots in the heated plots commenced an earlier elongation, 45_??_56 days earlier at 18_??_23°C and 26_??_38 days earlier at 9_??_15°C than those in the non-heated plot (Fig. 4 and 5). When the soil temperature was below 23°C in winter, roots of Poncirus trifoliata, C. junos and C. leiocarpa, the most cold resistant varieties, showed the most rapid elongation, followed by those of C. Hassaku, C. Aurantium, C. Funadoko, C. Tamurana and C. Tachibana, and the root elongation of C. sinensis var. Fukuhara, var. brasiliensis and C. intermedia, less cold resistant varieties, was delayed. And the increment of root elongation in the cold resistant varieties decreased as the soil temperature was increased.
4. Generally speaking, the roots in the heated plots showed a better daily elongation over a long period than those in the non-heated plot (Fig. 4). As in Fig. 6 and 7, the cold resistant varieties showed a better growth at 9_??_15°C; especially, Poncirus trifoliata, C. junos and C. leiocarpa grew most vigorously. On the other hand, the growth of the less cold resistant varieties was retarded. And Poncirus trifoliata, C. leiocarpa and C. junos increased in fresh weight a little less than twice as much as at 3_??_13°C; C. Aurantium, C. Funadoko, C. Tamurana and C. sulcata twice to three times; C. Natsudaidai, C. intermedia and C. Tachibana a little over three times; C. sinensis increased more greatly. In consequence, the most suitable rootstocks for the winter soil in Kochi, where the soil temperature in winter remains at 8.5°C or above at 50cm or more in depth, will be the varieties with deep root system, that is, C. junos and C. Natsudaidai, and the most cold resistant varieties, namely, Poncirus trifoliata, C.junos and C. leiocarpa, followed by C. Funadoko and C. Aurantium.

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The experiment was made to investigate the effect of storage temperature on keeping period and dessert quality of persimmon fruits, and to determine more desirable storage temperature and the maximum length of time for the fruit to be stored advantageously. At the same time, the effect of packing in polyethylene bags was also studied. Two varieties, Hiratanenashi (astringent variety, harvested on October, 17, 1955) and Fuyu (non-astringent variety, harvested on November, 13, 1955), were tested. One half of these fruits were packed in polyethylene bags of 0.02mm in thickness with dimensions of 12×30cm, three persimmons in each bag. Samples were stored at room temperature, 5°, 0°, and -15°C. The results are as follows.
1. The rate of softening, loss of weight and shriveling, and damages were much more rapid at room temperature than at the lower temperature. The contents of sugar, acid and ascorbic acid in the fruit also decreased rapidly with the increase of the storage temperature, but, when the fruit was kept at -15°C, it showed their gradual but slight decrease over a long period of time. It was noted that the content of soluble tannin was decreased during storage at room temperature, 5 and -15°C, while at 0°C the decrease was very slight.
2. Fruits in polyethylene bags were still in good condition with negligible shriveling and lost only about 1 per cent in weight during five months storage. The concentrations of oxygen and carbon dioxide gas in polyethylene bags were not so different as to compared with the atmosphere because the polyethylene bags used in this experiment was gas permiable. Therefore, they seem to be not so effective so far as the after ripening was concerned.
3. Maximum length of time that the fruits may keep their marketable quality was judged from the texture and the condition of decay. Those were approximately as follows. Hiratanenashi; one month at room temperature, one to two months at 5°C, two to three months at 0°C and throughtout the year at -15°C. Fuyu; two months at room temperature, two to three months at 5°C, three to four months at 0°C and throughtout the year at -15°C.
4. Judging through this experiment, the most desirable storage temperature for Hiratanenashi was found to be about -15°C, because of its fine texture, higher content of sugar, seedless character and the removal of astringency during freezing. For Fuyu, 0°C was found to be favourable.

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The observation on the root-system of cucurbits have been conducted since 1956 at the Division of Horticulture, Kyushu Agricultural Experiment Station. This paper reports the results of observation concerning the differences in the root-system among varieties of watermelon from 1956 to 1958.
1. Following representative varieties were chosen: (1) Asahi-Yamato, adapted for the culture in the dry paddy field or clay soil; (2) Miyko No. 3, adapted for the soil of volcanic ash in upland area; (3) Fumin, selected in the warmer region; (4) Hybrids among the varieties mentioned abrgVe (5) Triploid and tetraploid varieties.
2. Asahi-Yamato variety has a shallow rootsystem consisted of horizontal main spreading near the soil surface and of slender roots. On the contrary, in Miyako No. 3 variety, many thick roots are seen in both upper and lower layers of soil, and many vertical roots extend deeper.
3. Hybrid strains have a vigorus root-system. Generally, their roots are thicker and longer, and are distributed in a deeper layer.
4. In polyploid varieties, the roots are thick and vigorous, and show many branching. Further, many vertical roots are distributed in deeper layers.
5. From the results of this observation, it may be considered that there is a close relationship between the characters such as vigor of shoots, heat resistance and fruit quality, and the root-system.

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1. Experiments were carried out in 1957 and 1958 in order to investigate the degree of dormancy of buds of domestic and wild udoes (Aralia cordata THUNB.) collected from various districts in Japan. Stocks of these udoes cultured in Sakai, Osaka Pref. were grubbed up for three times at intervals of about one month from the latter part of October in each year, and were set in hot beds held at about 27°C.
2. Wide variation was found amomg wild udoes in the degree of domancy, but there was no apparent tendency with regard to the latitude or altitude. Domestic varieties, however, showed weaker dormancy compared with wild udoes.

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1. A study was carried out to investigate changes of respiratory mechanism of onion bulbs in relation to the dormancy, from last stage of bulb development to sprouting period of Senshu-nakate (Yellow Danvers) onions.
2. The amount of gaseous metabolism of onion bulbs decreased rapidly in the last stage of bulb development to reach too a minimum rate, and remained approximately constant at the minimum rate for a considerable period after the harvest, and commenced to rise gradually toward the sprouting period. This tendency was observed similarly both in the disk part (bottom part), which is considered to have important role on the physiology of onion bulbs, as well as in the whole bulb.
3. In the disk part of onion bulb, it seems that sugars might be decomposed completely through EMBDEN-MEYERHOF's pathway followed by TCA cycle. The unity value of respiratory quotient was observed throughout the experimental period.
4. Dehydrogenases, connected with TCA cycle in the disk tissue of the onion bulb, were found to have very low activity during the rest period, and then activated sharply in the middle or late of August, which period roughly corresponds to that of respiratory rise.
5. It was also observed that the addition of uncoupler of oxidative phosphorylation (DNP) resulted to introduce relatively little effect on the respiration of disk tissue during the rest period, but it caused remarkable increase of oxygen uptake at the critical period mentioned above, suggesting that the qualitative change of respiratory mechanism had occurred.
6. There was no influence of moisture condition on rooting and/or sprouting of onion bulbs for a considerable period after the harvest, notwithstanding the bulbs began rooting rapidly in the middle of August when they were placed on the moist sand.
7. These experimental results suggest that the accurate rest period of “Senshu-nakate” onion bulbs under the ordinary storage conditions would have been terminated by the middle or end of August, two months or more earlier than the visual sprouting period.
8. The variance in respiratory rate due to the. difference of variety was also measured. The respiration in the disk tissue of onion bulbs which belong to early-ripe varieties was lower than that of the late varieties at the last stage of bulb development, however, the reverse tendency was found from the rest period through pre-sprouting period. It seems, therefore, that early-ripe onions should go into the rest earlier than the onions of late varieties, but, they possibly lose more amount of substrates than the latter during the storage. Greater energy generation in early-ripe onions at pre-sprouting period might be favorable to induce earlier sprouting.

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This research was carried out from 1955 to 1959 to study the influence of storage temperature for onion bulbs on the dates of bolting and flowering and the yield of seeds at Tsuruoka, Yamagata Prefecture.
Storing mother bulbs at 20°C or above (especially above 30°C) delayed bolting and flowering and reduced the yield of seeds. In Sappro-ki variety, in which flower buds were differentiated in fall, storage at 30°C affected adversely the development of flower buds, making the inflorescence deformed and sterile.
Cold storage at 0-5°C also caused later bolting and smaller yield of seeds than the storage at moderate temperature.
Storage at about 10°C accelerated development of flower buds in the stored bulbs, leading to earlier bolting than at higher or lower temperature.
The date of bolting was influenced so markedly by the date of melting of snow cover and the growing conditions in spring, that storage temperature of bulbs had relatively little effect on the date of bolting as compared with climatic conditions.
Based on the above mentioned results, the favorable temperature for storing onion bulbs for seed production was discussed.

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Leaves of the head lettuce sown on March 25 started a radical growth on May 24 and the growth was most vigorous during the head formation. Their physiological situation was compared with that of the previous ones on June 3. The values of water content and specific electric conductivity of expressed cell sap decreased, but the specific gravity of tissue powder and the corrected concentration of expressed cell sap increased.
The water content of the leaves of the upper parts during the early period of the growth was smaller than that of the leaves of the lower parts of the plant, while during the heading period the leaves of the upper parts kept more water than those of the lower parts. The relation of the water content to the leaf position was reversed on June 3.
The values of the specific gravity of the tissue powder during the early period of growth were higher in the upper parts. During the heading period both the outer leaves and the inner parts of the head showed the similer tendency mentioned above, but the leaves on the outer parts of the head showed the converse tendency.
The values of the specific electric conductivity of expressed cell sap and the water extract of the tissue powder of the leaves decreased in the leaves of the upper parts during the whole growing period.
From the facts mentioned above, it is considered that the head lettuce remarkably showed the physiological changes both in growth and heading. The production, accumulation and translocation of the assimilated substance occurred in all leaves. Remarkable quantities of soluble matters were accumulated in the leaves on June 3, and at the same time both formation and growth of the leaves were active in the inner part of the rossett.
Accordingly, this period is considered to be the begenning of the heading.

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The purposes of the present study were to determine what levels and what proportions of the elements, nitrogen, potassium, calcium and magnesium, might best and most economically satisfy the nutritional need of muskmelon plants.
Plants of, the Earl's Favourite variety were grown by the method reported in the previous paper. Details of the design of fertilizer treatments are presented in Table 1. The results obtained are presented in Tables 2 to 7, inclusive. These data can be summarized as follows.
1. The main effects of nitrogen were to inhibit vigorous growth, to decrease the leaf, stem and fruit weights, to depress soluble solids and external appearance, to lower the pH value of soil, to depress the nitrogen, phosphorus, potassium, calcium and magesium amounts in the whole plants, and to increase the percentage of nitrogen in various organs of the plant.
2. The main effects of potassium were to inhibit vigorous growth, to depress soluble solids, to lower the pH value of soil, to increase the potassium amount in the whole plant, to decrease the nitrogen and calcium amounts in the whole plant, and to increase the percentage of potassium in various organs of the plant.
3. The main effects of calcium were to promote vigorous growth, to increase the leaf, stem, root and fruit weights, to improve soluble solids and external appearance, to increase the pH value of soil, to increase the nitrogen, phosphorus, potassium, caclium and magnesium amounts in the whole plant, and to increase the percentage of calcium in various organs of the plant.
4. The main effects of magnesium were to depress soluble solids, to lower the pH value of soil, to increase the phosphorus and magnesium amounts in the whole plant, to decrease the calcium ammount in the whole plant, to increase the percentage of magnesium in various organs of the plant, and to decrease the percentage of calcium in various organs of the plant.
5. The interactions of nitrogen and potassium were to decrease fruit weight, and to decrease the nitrogen, phosphorus and potassium amounts in the whole plant.
6. The interactions of nitrogen and calcium were to increase the root weight, to improve soluble solids, to lower the pH value of soil, and to decrease the phosphorus, potassium and calcium amounts in the whole plant.
7. The interactions of calcium and magnesium were to increase phosphorus and potassium amounts in the whole plant, and to decrease the calcium and magnesium amounts in the whole plant.
8. Very few secondary interactions were obtained from the variables.
9. The plants, which received 7g of N, 10g of K₂O, 40g of CaO and 0g of MgO per plant were able to maintain vigorous growth and produced fruits of high quality. The results seem to indicate that these amounts are recommendable for the muskmelon culture.
10. The amounts of N, P₂O₅, K₂O, CaO and MgO in the whole plant that received 7g of N, 10g of K₂O, 40g of CaO and 0g of MgO were 4.4, 1.6, 6.8, 9.3 and 1.2g respectively, per plant.

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1. Experiments were carried out with large (16-18g) and small bulbs (1.7-2.0g) of William Pitt variety in a field of dune. The standard amounts of elements supplied to the plots were 26.3kg of nitrogen (Ammonium sulphate), 22.6kg of phosphorus (calcium super phosphate), 30.0kg of potassium (potassium sulphate), per 10a, and the test plots were set up by varing amounts one of the three elements: graded eleven degrees as from 0 to 37.5kg. Besides the eleven plots an unfertilized plot was added as control.
2. In general, the greater the amount of each element supplied, the higher the plant height, and with increased nitrogen fertilizer it was observed that their leaves became darker green. The flowering time had a tendency to be delayed with increasing the amount of nitrogen or potassium fertilizer, and to be hastened with increasing phosphate fertilizer. The increased rate of bulb weight and bulb number was most influenced by increasing the nitrogen supply, and less influenced by phosphate supply.
3. It was not difficult to find some relation between the number of split coat bulbs or the formation of droppers in the small bulbs, and the amount of each fertilizer supplied. The water content of bulbs tended to increase with increasing nitrogen or potassium and decreased with increasing phosphate.
4. It was also found that the differentiation of the flower bud occurred earlier in bulbs produced by supplying large amounts of nitrogen or phosphate, but the amount of potassium fertilizer seemed to have no effect on the flower bud differentiation. And, in the phosphate and the potassium plots, the relation between the earliness of flower bud differentiation and the smallness of water content of bulbs was recognized, but in nitrogen plots, it was hard to find such relation.

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A study was made to know the effect of nutritional contents in corms on the flowering in gladiolus.
Corms of the variety Spotlight, which were shown in Table 1, were planted in benches containing sandy soil in the experimental greenhouse at Kagawa University on March 19, 1959, and they were grown with water alone (no fertilizer was added).
Number of germinated corms, date of flowering, number of plants died, number of blind stalks, and number of flowered plants were recorded. On July 31, all plants were dug up, and fresh weight of tops, fresh weight of corms, and number of cormels were recorded.
Cormels of the same variety which were shown in Table 3 were planted in the same greenhouse on March 20, and they were dug up on June 4, and the fresh weight of the plants was measured. The reasults obtained are summarized as follows:
1. Earlier flowering was observed in the plants to which N 100 ppm and P 25-50 ppm were applied in the previous year, and later flowering in -N plants or the plants to which N 200 ppm alone was applied.
2. Percentage of germination and percentage of flowering were high in the plants to which nitrogen was applied in the previous year, and percentage of plants died and percentage of blind stalks were high in -N plants. Several malformed plants were observed in the plot in which N 200 ppm alone was applied.
3. Number of florets, height of plants, fresh weight of tops, fresh weight of corms, and number of cormels were increased.
4. No significant differences were observed in the number of leaves and fresh weight of cormels.
5. From the results above mentioned it seems that the most superior was the plant to which N 200 ppm and P 50 ppm were applied in the previous year, and the nutritional contents in these corms were 1.99% of nitrogen, 0.31% of phosphorus and 0.57% of potassium in dry matter. The second was the plant to which N 200 ppm and P 25 ppm were applied, and 1.82% of nitrogen, 0. 22%of phosphorus, and 0.49% of potassium were contained in corms.

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