Morphological and histological observations were made on the fruit development of Satsuma orange. The flowers bloomed in mid-May, and the fruits matured in mid-November.
1. Rapid increase in the peel thickness began in early June. It was due principally to the active division of albedo cells at this stage. Cell division in mid-albedo almost ceased on about June 10, the fruit diameter at that time being about 9mm, and then the derivatives enlarged. The epidermis and hypodermis of the peel seemed to continue their cell division until considerably late stage in the fruit growth.
2. Juice sac primordia appeared in mid-May. The membranous epidermis of mature juice sacs consisted of fiber-like cells which were oriented parallel to the longitudinal axes. The epidermal cells at the base of juice sacs began to elongate in early June while the cells near the apex of the sacs continued to divide until much later stages. The latter cells began to elongate later. Elongating cells splitted simultaneously along their longitudinal axes. This splitting continued until late June to early July. Then these derivatives gradually thickened.
3. The inner epidermis of the lateral walls of pulp segments in the mature fruit consisted of fiber-like cells which were oriented to the radial direction of the fruit. The majority of epidermal cells began to elongate already at the time of flowering and simultaneously splitted along their longitudinal axes. The splitting continued until July. The radial growth of the segment walls was due mainly to the elongation of cells. On the other hand, they owed their longitudinal growth principally to the active cell division.
4. After mid-October the tissue of pulp segments mostly failed to grow while the peel still contiuned its growth. Consequently the spongy tissue of central axis was split and pulled apart as the peel growth progressed.
5. Relation between the fruit weight and the number of juice sacs was studied. Larger fruits tended to have more juice sacs. The fruits from a tree of low vigor contained notably few sacs. Nu-tritive condition and/or food materials within the tree seemed to exert a remarkable influence on the formation of juice sacs.

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Effect of harvesting date of fruits on the deve-lopment of flowers and shoots in the following year was investigated on the potted Satsuma and Early Satsuma orange trees for several years.
The results showed that the earlier the fruits were harvested, the more the flowers developed in the following year, and even when one half of the fruits were picked early, the effect was also evi-dent. Pickings before mid-November increased the number of flowers than the pickings thereafter.
The number of shoots sprouting in the next spring was not affected by the date of harvesting fruits, even if fruits were harvested early, and it was decreased in the cases where the number of flowers was increased markedly. No significant differences were found among the length and number of nodes, of newly developed shoots on the trees whose fruits were harvested in the different dates.

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1. With two 6-year-old fig trees (MASUI DAU-PHINE) planted in the orchard of the Horticultural High School of Osaka Prefecture, the yearly amounts of the five nutrients absorbed were estimated, by separating all parts of _??_ tree (trunk, branches, and roots) into new and old tissues, and analyzing them for nitrogen, phosphorus, potassium, calcium, and magnesium.
2. The results showed that the dry weights of a whole tree and its new tissues were 8.03kg and 6.08kg respectively, The latter was 75.7% of the former. The weights of new tissues of various parts of a tree were as follows: fruits, 3.31kg; leaf, 1.00kg; one year old branches, 0.40kg; tops (not including leaves, fruits, and one year old branches), 0.8kg; fine roots, 0.07kg; roots (not including fine roots), 0.49kg; total, 6.08kg.
3. In comparing each new tissue as to the content of each of the five nutrients, the highest value of N was found in the leaves and immatured fruits; that of P₂O₅ in roots of medium and large size; that of K₂O in fruits, medium and small roots, and that of CaO and MgO in leaves. In addition, new bark tissues always indicated a higher value of all ele-ments than the new wood tissues.
4. The total amounts of each five nutrients con-tained in new tissues of a tree were: N 70.0g, P₂O₅ 20.3g, K₂O 79.6g, CaO 104.5g, and MgO 22.6g. On the basis of this data, the yearly amounts of the nutrients absorbed by 100 trees which were planted in a field of 10 ares, with a production of 2696.35kg, came to N 7.00kg (index number 10.0), P₂O₅ 2.03kg (2.9), K₂O 7.96kg (11.3), CaO 10.45kg (14.9), and MgO 2.26kg (3.2).

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Two vines each of uniform bearing Black Queen were dug up nine times during the period from April, 1954 to March, 1955, and leaves, shoots, stems, roots and berries were separately analysed for their contents of crude fiber, crude protein, soluble sugars and starch.
Moisture in berries, crude fiber in fruiting shoots, canes, stems and roots, crude protein in leaves, and soluble sugars in berries were notably abundant, and starch was rich in canes, stems and roots.
The contents of crude fiber and crude protein in berries, leaves and fruiting shoots increased with growth, the rate of increase being high up to the time of pit hardening, and thereafter the contents of soluble sugars as well as starch increased mark-edly.
In older tissues such as canes, stems, and roots, contents of crude fiber and starch were low in the growing season (from March to November), and high in the dormant season (from December to February), while soluble sugar content was, on the contrary, high in the growing season and low in the dormant season. Little seasonal fluctuation of crude fiber was noticed in those tissues.

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The experiment on the effects of green manure application on the yield and growth of Satsuma orange trees has been conducted since 1946 at Ehime Fruit Tree Experiment Station, Five experi-mental plots have been set up in the terraced orchard on diluvial soil. The total amount of each element (nitrogen, phosphorous and potassium) applied was same in all plots. In the “100% green manure” plot, green manure alone was applied every year, lupin or broad bean being applied in April and soybean in September. The “0% green manure” plot was applied with chemical fertilizers alone with no green manure. In the 75, 50 and 25% green manure plots, the amounts of green manure applied were the designated percents as much as that applied to the “100% green manure” plot, and the rests were supplemented with the chemical fertilizers. The Satsuma orange trees on trifoliate orange were 25 years old in 1946 when the experiment was started. Each plot was con-sisted of six trees.
1. The yield in the 0% green manure plot was larger than that in the 100% green manure plot for the first three years (1946 to 48), nearly equal to the latter for the following three years (1949 to 51), and then exceeded by the latter since 1952. The 25%, 50%, and 75% plots situated between the 0% and 100% plots in their yields. Since 1953, the yield of 25% plot approached to that of the 0% plot, and the 75% plot to 100% plots. The trees. in the 0% plot have gradually lost their vigor, and since 1957 they have been so exhausted that they could hardly be used in the experiment. The yield of the 50% plot has been intermediate between those of the 100% and 0% plots.
2. Measurements of size and shape of fruits for 7 years, 1950 to 56, showed that the more the green manure was applied, the larger the fruit size and the flatter the fruit shape. Fruit growth during July to November was better in the 100% plot than. in the 0% plot.
3. The experiments on fruit storage conducted in 1948 to 53 revealed that the percentage of storage loss due to molds was less in the plots receiving larger amounts of green manure.
4. Tree volume and trunk circumference in 1960 were larger in the plots receiving larger amount of green manure, showing the same tendency as, the results on the yields for 1956 to 59.

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It has been reported that the pollen of onion is susceptible to rain or high relative humidity. It is doubtful, however, whether rainfall or high humidity induces direct injury to seed production of the onion. So experiments were carried out to investigate how various factors affect the fruit setting under the natural and artificial conditions.
1. Fruit setting under the natural and artificial conditions
(a) Under the natural condition
The influence of weather before and after the flowering of a floret on its fruit setting was investigated. When rain continued for one or two days after the flowering, it inflicted little injury on the fruit setting. However, the rainfall which continued for two days from the next day of the flowering did much injury, and the most severe injury occured when the rain continued for three days from the next day of the flowering or for four days after the flowering. While, the clear weather for five to six hours interrupting the continous rain reduced the injury exceedingly.
(b) Under the artificially maintained continuous wet conditions
A floret was kept under the artificial rain for one to five days after the flowering or for four days from one to four days after the flowering. In these experiments the results similar to those mentioned above were obtained.
(c) Under the artificial alternate wet and dry conditions, four plots were provided as follows; 1) wet every night, 2) wet every forenoon, 3) wet every other day, and 4) dry throughout the period (check). Little injury was inflicted on the fruit setting by the raining treatment, and fertility of the treated plants was about the same as the check.
2. The dehiscence of anther as influenced by temperature and relative humidity
(a) Temperature: At 35-40°C, six to ten hours was required from the flowering of a floret to the dehiscence of its innerwhorl of stamens, and thir-teen to twenty hours to that of the outer whorl of stamens. The time was prolonged by three to eight hours at 30°C. At 25°C, the dehiscence of the anther required twice as many hours, and at 20°C, four times as many hours after the flowering as at 35°C.
(b) Relative humidity: The relative humidity was controlled at 50, 60, 70, 80, 90, and 100per cent. No difference in the time of the dehiscence of the anther was found among fifty to seventy per cent relative humidity. At eighty per cent relative humidity, the dehiscence of the anther required some more time than at fifty per cent relative humidity. At ninety per cent relative humidity, it required twice to three times as many hours as at fifty per cent relative humidity, and no anther dehisced in saturated humidity.
3. The seed production of various plants under the artificial raining
Ten kinds of plants were used to compare their resistance to rain with that of the onion. They were kept under the artificial raining for four days. With snap beans and gardenia, the flowers of which are formed as the anthers are not exposed to the rain, fruit setting was little injured by the. raining treatment. With carrot, Cancalis scabra MAKINO and Onion, the pistils of which retain its fertilizing capacity for three to four days after flowering, fruit setting was injured only when the raining was continued more than three to four days. The fruit setting of the other plants (Veronica persica POIR., Oxalis corniculata L., Polygonum-aviculare L., Polygonum capathifolum L., Polygonum senticasum FRANCH et SAV. and egg plant) was severely injured by the raining and seeds were-not produced. After the raining treatment was stopped, however, the plants produced seeds again.
4. The germination of pollens as influenced by relative humidity
The materials used were the same as mentioned. above. Some kinds of plants were found to have pollens very resistant to high relative humidity. The pollens of snap beans, gardenia, lily, etc.

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Butterbur, Petasites japonicus MAXIM., called “Fuki” in Japanese, is a deciduous perennial herb belonging to Compositae, and is growing wild almost all over Japan. Gigantic butterbur, subsp. giganteus KITAM., commonly called “Akitabuki”, is restricted in its distribution to the northern Japan such as Hokkaido and Tohoku districts. Butterbur is cultivated as a leaf-vegetable or for processing in Osaka, Aichi, Akita and other prefectures, and its cultivation has a long history.
Stocks of cultivated and wild butterburs have been collected from various localities of Japan and cultivated for several years at the experimental farm of the University of Osaka Prefecture in Sakai City. Morphological, ecological and cytological studies have been carried out in order to elucidate the origin of cultivated varieties in relation to wild types and to provide basic information for future works of butterbur breeding. The present paper deals with the morphological and ecological studies on the cultivated and wild butterburs and on the geographical variations of those characters in wild types in relation to the latitube and altitude of their habitats.
1. The two cultivated varieties, “Aichiwasebuki” and “Mizubuki”, are distinguished in their larger size of leaf blade, longer petiole, more vigorous growth habit, and earlier sprouting of leaves in spring than those of wild ones (Fig. 2).
2. Wild butterburs showed a wide range of variations in their morphological and ecological characters when grown under the same conditions, but any definite geographical differentiation of those characters could not be found. Some stocks of wild butterbur had characters as excellent as those of the cultivated ones (Figs. 1 and 3).
3. The habit of “Akitabuki” to grow gigantic was not manifested in the experimental farm where it was warmer and drier than in its habitat (Figs. 1 and 2).
4. It was found that the seeds of wild butterburs did not undergo dormancy.
5. It was assumed that the cultivated varieties might be derived from certain wild stocks having desirable characters as vegetable crop, because of the fact that the useful characters can be easily and frequently found in wild ones.

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In the present paper, relative salt tolerance and mechanism of salt injury of nineteen species of vegetable crops were discussed with special reference to mineral nutrition, on the basis of the results of the sand culture studies previously reported by the author. The sand cultures were made under glass, using HOAGLAND's solution as the basic solution (control), with NaCl added at various concentrations ranging from 1000 to 16000 ppm.
1. Relative salt tolerance of vegetable crops was evaluated according to the concentration of NaCl in the solution corresponding to a 50 per cent reduction in fresh weight of above ground parts (including fruits for fruit vegetables) or of the edible portion. The results obtained by these two ways did not always coincide with each other.
2. Stimulative effects of 1000 or 2000 ppm treatment on the vegetative growth of such crops, pakchoi, cabbage, radish, chinese cabbage, celery, and tomato might be due to Na in most cases.
3. Percentage of the dry weight of tops, in general, decreased in high salt treatments in fruit vegetables, but did not vary so markedly or slightly increased in high salt treatments in the other vegetable crops, and that of roots of root vegetables tended to increase with increasing salinity.
4. The ability of crops to survive in increasing salinity was almost parallel to the salt tolerance represented by yield decrement. In general, the rate of dead leaves increased markedly as the salt concentration came near to kill plants, and the death of plants generally occurred in consequence of severe dying off from older leaves.
5. Symptoms of salt injury were variable with crop species; symptoms caused by the high osmotic pressure of the nutrient solution, by deficiency of essential elements, or by toxicity of excessive accumulation of Na or Cl occurred singly or accompanying each other, and they affected adversely the quality of certain crops.
6. With increasing salinity, the content of both Na and Cl in leaves increased almost linearly in most crops, but often exponentially in considerably salt tolerant Cruciferous crops. The content of Na in leaves varied widely with species, and tolerant crops tended to accumulate higher concentration of Na in leaves than did sensitive crops, while such relationship could not be found as to Cl in leaves. Direct toxicity of excessive accumulation of Na or Cl in plants could not be considered as the primary cause of salt injury in most crops. Content of Na or Cl in roots was not related to salt tolerance. It was suggested that there might be some important relationships between salt tolerance and the trans port of Na or Cl from roots to tops or Na/Cl ratio in leaves.
7. Content of K, Ca, or Mg in leaves was in antagonistic relation with Na, and as the salinity increased, tended to decrease more markedly in tolerant crops than in sensitive crops in general. Therefore, such interference in absorption of essential cations might not be the primary cause of salt injury in general, but its possibility to accelerate the injury might be of importance occasionally. The degree or the order of the antagonism of each essential cation to Na varied with crop species and with the concentration of NaCl in the solution.
8. Tolerant crops usually showed rather high K content in leaves at control, andshowed significantly higher Na+K content in leaves in the NaCl treat ments than did sensitive crops, while such definite relationships were not found in roots. The K/Na ratio in leaves was not closely related to salt tolerance. The total amount of four cations, Na, K, Ca and Mg, in leaves slighty increased with increasing salinity in most crops, and was not related to salt tolerance. Milliequivalent ratio of Na, K, or Na+K to total cations in leaves was not so closely related to salt tolerance.9.

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Since 1954, the green wood grafting has been successfully used for the propagation of greenhouse Hibiscus in our botanical garden. Attempts were made to apply the method to other outdoor trees.
1. The experiments were carried out during 1957_??_1960 to ascertain the possibility of green wood grafting in maple, camellia, chestnut, grape, Japanese plum, kaki, orange, pear, peach and rose.
2. The method of the so-called “green wood grafting” is as followed. The growing soft scions, usually with a few leaves on them, are grafted on green shoots of stocks by the method of the side or cleft grafting, and thereafter enclosed in the cover of vinyl sheet and screen for 10_??_30 days. In this method, bud forcing of stock or storage of scion is not necessary.
3. High percentages of graft union were obtained in the greenwood grafting in maple, camellia, orange, peach and pear. The success of grafting in maple and camellia which have been recognized as the difficult ones, is of great significance in the nursery practice.
4. Satisfactory results were not obtained in chestnut, grape, Japanese plum, kaki and rose.
5. The green wood grafting of deciduous trees was possible duriug a rather long period from late April to August, while that of evergreens from middle May to early October, but the best season was found to be May-July in the former group and June-August in the latter, respectively. These results suggest the possible use of the method for practical propagation of certain woody plants, especially of camellia and maple whose graftings are otherwise rather difficult.

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Small corms (average weight 8.8g) of Spotlight variety were planted in benches with sand in glasshouse on March 21, 1960, and 100ppm of nitrogen was supplied twice a week from April 21 to June 27 in the N-plot, while, no nitrogen was supplied in the 0-plot.
Samplings were made every week from May 31 to June 21. The nitrogen contents in the top were measured by semimicro-Kjeldahl method, and the auxin contents in the flower buds were determined by the avena curvature test with following procedure: one gram of flower buds in each plot were sliced into small pieces and extracted with 70ml of peroxide free ether at 2°C for 20 hours. After the ether was removed the residue was disolved with 1 ml of distilled water, to which 20 pieces of agar blocks (10mm³, 2%) were placed. 1. Height of plants, weight of tops and percentages of flowering were lower in 0-plot than in N-plot. Color of 0-plot plants was pale yellowish green. It was apparently a nitrogen deficient symptom. 2. The percentages of nitrogen in dry matter of tops were lower in plants of 0-plot than in those of N-plot. Although the nitrogen content in a plant of N-plot increased with growth, that of 0-plot did not increase above a certain level. 3. About the contents of auxin in the flower buds, there was no difference between 0-plot and N-plot. 4. On the anatomical observation of the flower bud, the blind bud of nitrogen deficiency plant died in the same manner as that caused by short day, except all florets died at the same time.
5. From the results above mentioned it seems that nitrogen deficiency itself in plants is the cause of blind.

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It is well known to the growers that suckers produced after flowering of chrysanthemums form rosette in autumn under natural conditions. Usually the rosette suckers are taken into the green house in December or January for the purpose of forcing culture by the commercial growers. But those rosette suckers elongate slowly unless they are subjected fully to low temperature. Therefore, the suckers which will be planted early in winter are obtained from high altitude areas where temperature drops earlier. This suggests an effectiveness of the vernalization on chrysanthemum. SCHWABE, who had investigated minutely the vernalization of chrysanthemum, reported that the suckers produced after flowering formed rosette under the short day condition as a result of devernalization, and in consequence the suckers required to be subjected to low temperature before growing. But in Japan the suckers of chrysanthemum developed after the flowering under shade-culture in the early summer months elongate normally, form the flower bud and come into bloom in autumn. In U.S.A., it is said that chrysanthemums can be made to flower all the year round without being subjected to the specific low temperature. These facts gave the author many questions which are briefly explained below. (1) How many times shall we be able to repeat flowering and propagating of suckers in the autumn-chry-santhmum under high temperature condition? (2) When the suckers do not flower in these cases, can these plants be made to form rosette at the apex by subjecting to short day treatment after stem elongation? (3) If the sucker forms rosette, can we derosette or check it?
This study was designed to clear up the above questions. All the experiments were carried out in a glass frame maintained over 18°C in 1958 and 1959. The material plant was the early variety “Shin-Toa”. Flowering and rosetting behaviour of suckers were repeatedly examined, and the rosette plants formed in this experiment were tried for the possibility to be derosetted by spraying the gibbe rellic acid (GB) of 50 and 100 ppm, and checking of rosette formation by applying GB (50 ppm) was tried.
1. Most of suckers, developed _??_on the plants which bloomed under high temperature condition, had flowers, but some formed rosette after stem elongation. While the suckers, developed on those flowering plants, formed rosette after stem elongation.
2. The suckers, developed on the plants which were applied pinching of the growing point under short day or long day condition, flowered and formed no rosette, and the suckers of these flowering plants formed rosette when these plants received short day treatment after stem elongation.
3. Stem elongation of suckers, developed on the plants which were flowered or applied pinching of the growing point under short day condition, was slower, even though these suckers were laid under long day condition, than that of suckers which developed on the plants which were applied pinching of the growing point under long day condition.
4. Spraying of GB (50 and 100 ppm) or long day treatment was found to be effective in derosetting of suckers which had been formed rosette under short day after stem elongation.
5. Derosetted plants by long day treatment again formed rosettes slightly at the growing point by short day treatment, but soon these rosette plants elongated and flowered.
6. As the number of times of GB spraying increased, the derosetted plants flowered earlier at the terminal bud, elongated its stem longer and increased the total number of the flower buds.
7. Resetting of suckers, which would be elongated under long day but would form rosette by short day treatment, was inhibited by GB spraying (50, ppm) 5 days before, or at the beginning of short day treatment. But inhibition was seen only slightly, when GB spraying was done 15 days after short day treatment.

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Snow-Camellia is a new species which is natively distributed near the northern limit .of camellia distribution along the coast of Japan Sea. As Niigata Prefecture is situated approximately in the center of the distribution of Snow-Camellia, Camellia, as well as wild and cultivated Snow-Camellias are observed in various parts within the prefecture, the authors aimed to investigate the distribution and the variation of them to contribute to breeding camellia.
In the mountainous districts up to about 1, 400 meters above the sea level, many pure wild Snow-Camellias were widely distributed, and in the plain district near the coast which includes Sado Island, Snow-Camellia and Japonica-Camellia grew together, and the intermediate type formed as the result of cross-fertilization between the two species were found, too. Lots of Snow and Japonica-Camellia having ornamental value were witnessed in the farm yards, and those promising strains seemed to be originated from the native species in the neighborhood. The distribution of cultivated Snow and Japonica-Camellia was almost coincided with that of the wild camellia.
As the cultivated Snow-Camellia had furnished abundant variations in form, size, and color of flower, it is expected that it must be favorable materials for camellia breeding, even though its ecological characters are ignored.

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