A study was made as to the effect of 2, 4, 5-TP (2, 4, 5-trichlorophenoxypropionic acid) on the coloration, maturity and growth of apples and stone fruits (peach, plum, Japanese apricot, apricot and cherry), The present experiments were carried out at two localities (Sapporo and Yoichi) from 1955 to 1958.
The. results obtained are as follows:
Apple.
1. By spray applications of 2, 4, 5-TP, the colora-tion and maturity of the fruits are hastened re-markably. It is obvious especially in summer apples. They can be harvested 10 days to two weeks earlier than untreated fruits.
2. In most cases sugar content of the fruits is also increased.
3. Apples are not enlarged by the spray applica-tions of 2, 4, 5-TP.
4. As a result of storage tests, it was ascertain-ed, that the keeping quality of fruits is not at all affected by applications of 2, 4, 5-TP.
5. It was confirmed that applications of the che-mical about one month before usual harvest time with concentration of 20 ppm are most suitable for all apple varieties, excepting McIntosh, for which 40 ppm is recommendable.
Stone fruits.
1. Distinct enlargement of fruits was induced in all stone fruits. In such cases the growth of pits kept pace with that of the fruits, which is a fact that has never been reported hitherto.
2. Noteworthy acceleration of maturity of the fruits resulted in all stone fruits. As a result of it, intense red coloration occurred in plums and cher-ries.
3. Sugar contents of the treated fruits became higher than that of the untreated fruits.
4. Concentration of 40ppm was proved to be suit-able for most of the stone fruits, with the exception of peaches, for which 20ppm is recommendable. Malformation of fruits, in peach, is likely to result when 40ppm is applied.

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1. Experiments were carried out in 1957 and 1959 to study physiologically the cause of so-called sunscald disease of grapes which used to deuelop on the fruit at the pit-hardening stage, especially in the glasshouse growing.
2. This disorder usually occured on the sides of berries directly exposed to the sun-light; first appearing as a slight, brownish, scalded spot in the pulp tissue through the rind, and then gradually growing into a hollow after the collapse of the tissue. At times, the whole berry rapidly became soft and brownish as if boiled, and dropped from the branch after shrinkage. The anatomical observation of the affected tissue showed that the protoplasma of the cells degenerated necrotically and coagulated.
3. By wrapping the berries borne on the vine in vinyl bags, newspapers, and parchment papers of various colors, respectively, it was confirmed that the plots with black or white vinyl bags (having the highest daily fruit temperature) suffered from the disorder more than any other plots, regardless of the quality of light passed into them.
4. When treated in an incubator with high temperature, such as with 40°C air temperature (35°C fruit temperature) for 3.5 hrs., with 42°C (36.6_??_37.5°C) for 2 hrs., with 45°C (38.8°C) for 1.5 hrs., with 48°C (39.6_??_40°C) for 1hr., even normal berries had an attack of the disorder similar to that which developed on the vines naturally.
5. The respiratory rate of berries affected by high temperature and by heavy disorder was observed respectively in vitro, and the result was, that the higher the temperature of berries or the heavier the disorder, the more increased was the respiratory rate. In any case of extreme high temperature or very heavy disorder, however, the respiratory rate suddenly fell with an abnormal respiratory quotient.
6. Finally, as the result of chemical analysis, the disordered berries were found to contain less reducing sugar and tartaric acid than the normal ones, and that they accumulated alcohol and acetaldehyde in their affected portions. Thus, it is noticeable that with an artificial addition of acetaide hyde the tissue of normal berries becomes soft and brownish, accompanied by a reduction of the respiratory rate.

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1. Many investigators published their findings on the cause of the Jonathan spots which develop on the skin of apples. However, no definite conclu-sion nor established method of prevention have been published to this date. Therefore since 1956 the author has tried to solve this problem from the histological and physiological viewpoint, experimen-ting with such varieties as Jonathan, McIntosh, Ralls and Indo apples. This paper contains the results of these experiments on the spot develop-ment as influenced by the varietal difference in the structure of apple skin.
2. In the Jonathan apple, which seems to be most susceptible variety, cuticula formation on the skin was very slow as compared to the other varieties of apple, and the arrangement of epidermal cells remained brick wall like until about the middle of August. In the spot resistant variety, namely, Rails and Indo apples, cutin sediments were found on the side walls of epidermal cells early in June, and except for the bottom wall which touches the hypodermal cells, cuticule was formed on the walls of the epidermal cells about the middle of July. In McIntosh, a medium resistant variety, the struc-ture of the fruit skin, at first, seemed to change almost like that of Jonathan, but then became like those of Ralls and Indo.
3. In every variety, as the fruit grew some of the stomata showed signs of cracking in the middle of June, and the stomata gradually collapsed, dis-coloring their surrounding tissue and finally develop-ed into the lenticels. The Jonathan apple skin was very slow in this process, so that many stomata were still normal even late in August, when Mc-Intosh and Ralls already had well-developed lenti-cels.
4. In order to clarify the morphological property of the lenticels, some ripe fruits were separately treated with sudan III solution, methylene blue solution and formalin gas, and six hours later the reaction was observed. In Ralls and Indo, dye-sediments were detected only on the surface of the projected lenticels, showing no trace of dye-infiltra-tion in the inner tissue, while in Jonathan some of lenticels allowed dyes to infiltrate into the inner tissues. With formalin gas, the inner tissues of the skin of all varieties tested were damaged more or less through lenticels.
5. When the Jonathan spots were observed under the microscope, it became clear that the lenticels located in the center of the spot were either 1) those in which cork cambium had developed poorly, 2) or the stomata of which were still at the early stage of crack, 3) or in which the skin tissue around the stomata was about to crack. There fore, the author gave these lenticels the name of “openlenticels”
6. In the storage of the fruits which were treated with dye solution, Jonathan spots developed only on the fruits which allowed dyes to infiltrate. The fruits which suffered from Jonathan spots, afterward, were found to have transpired more water than the healthy apples. This fact suggested to us that for the development of Jonathan spots the existence of open lenticels should be considered as an important causal factor.
7. In addition, it was noticeable that when the fruits were stored at different temperatures and hu-midities after harvesting, Jonathan spots developed more rapidly on the fruits kept in a moist block than on those in a dry block, regardless of the stor-age temperature, and also they developed more rapidly on the fruits stored at a temperature of 20°C±5°C than on those at a constant temperature of 35°C or 0°C.

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Fruits of “Gin-yose”, a leading variety in Japan, were used as materials. Dry matter, carbohydrates, nitrogen, phosphorus and potassium contents were determined periodically throughout the development of the fruits.
Growth curve of fruit weight showed a double sigmoid curve. Both bur and pericarp grew gradual-ly for a while after flowering, and then made rapid growth. Growth rates of bur and pericarp were slowed down at the end of August, when embryo started to grow rapidly. Then, bur and pericarp resumed their rapid growth again with accelerated growth of embryo to maturity. It is possible to recognize two cycles in the growth of chestnut fruit.
Cycle 1. The first cycle was characterized by rapid production of dry matter in bur which cor-responded to about 70% of final dry weight. Phos-phorus and potassium accumulated rapidly, and insoluble nitrogen reached its maximum value in the bur.
In the nuts, concentration of reducing sugars was fairly high in this cycle, and their absolute amount reached maximum value temporarily at the end of this cycle. Both moisture and sugar contents in the bur were lower than those in the nuts.
Cycle 2. The second cycle was commenced by the-rapid increase of dry matter in the nuts at the ex-pense of dry matter production in the bur. About 85% of final dry matter of nuts was formed in this cycle.
The second cycle was also characterized by the-active growth of bur which was mainly due to. absorption of water. Although bur growth in fresh weight was as rapid as in the first cycle, increase-in dry weight was not so high in this cycle. In-soluble nitrogen decreased towards maturity, and potassium and phosphorus accumulated slowly. Concentration of reducing sugars in the bur rose to. maturity. It seemed that the increased absorption of water and softening of bur, especially of bur-flesh, in the second cycle related to the high con-tents of potassium and sugars.
In the nuts, high concentration of non-reducing. sugars occurred at the expense of reducing sugars. Rapid accumulation of non-reducing sugars and starch in the nuts was observed associating with the active growth of embryos. Most of the soluble-and insoluble nitrogen, phosphorus, and potassium, in the nuts were accumulated in this cycle.

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This study was made to determine the factors closely associated with the tomato fruit cracking in the summers of 1957 and 1958.
1. Although tomato fruit absorbed 0.6 to 2.4 grams of water at immersion in water, cracking did not occur unless it had approached to the pink stage.
2. Removal of two-thirds of the leaves from the vine increased concentric crackings, but decreased radial and side crackings. Shading of fruits decreas-ed all types of crackings. The least cracking was found on the plants whose leaves were removed and whose fruits were covered with black paper bags.
3. Soil moisture also had a marked influence on the cracking of tomato fruits. By keeping plants at low soil moisture, severe of cracking was reduced, while enhanced at high soil moisture. The change from low to high soil moisture induced more cracks than that from medium to high soil moisture.
4. Among the factors concerning the cracking, elasticity of fruit skin, sugar content of fruits, and root pressure seemed to be most important.
5. Radial cracking was induced by internal ex-pansion pressure of fruit, and concentric one by water uptake through the corky spots on the fruit.

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From 1957 to 1960, vegetable crops were grown in sand culture under glass at various concentrations of NaCl to study their relative salt tolerance, visual symptoms of salt injury, and effect of NaCl on absorption of nutrient elements and carbohydrate content of plants. HOAGLAND's solution was used as the basic solution (control), and 1000, 2000, 4000 8000, or 16000 ppm of NaCl was added to it. The present paper, as a part of the studies, deales with the results of experiments on six fruit vegetables, namely, tomato, pepper, cucumber (the 1000 ppm treatment was omitted), broad bean, snap bean (the 100 and 16000 ppm were omitted), and strawberry.
1. With increasing concentration of NaCl, plants were dwarfed and the emergence of lateral shoots was restricted. Concentrations of NaCl above 8000 ppm in cucumbers, broad beans, and snap beans, and above 4000 ppm in strawberries caused severe dying off of older leaves and finaly death of entire plant. With the increase of NaCl, the fresh weight of tops (vines) was reduced, excpet that tomatoes showed the greatest weight at the 1000 ppm treatment The yield of fruits, however, was reduced in any crop with the increase of NaCl. The concentrations of NaCl in the solution corresponding to a 50 percent reduction in yield of fruits of tomatoes, peppers, cucumbers, broad beans, and strawberries were about 3500, 3000, 3000, 2500, 2000, and 1000 ppm, respec-tively. In tomatoes, and peppers, the reduction in yield of fruits was more significant than that of vines. The dry weight percentage of tops generally decreased in high salt treatments.
2. The number of flowers tended in general to parallel declining vegetative growth as salinity in-creased. The rate of fruit setting was reduced mark-edly in the treatments above 8000 ppm in tomatoes and above 4000 ppm in peppers. In most crops, the dates of first flower opening and of first harvesting were not so remarkably affected by NaCl treatments, but in peppers, severe shedding of early fruits in higher salt treaments retarded the first harvest. No apparently harmful effects of NaCl treatments were observed on the fertility or germination percentage of pollens, and on the seed set.
3. Symptoms of salt injury were as follows: In tomatoes, leaves were dark green from 1000 to 8000 ppm, but were chlorotic at the 16000 ppm. In pep-pers, leaves were chlorotic and leaf margins incurl-ed at the 16000 ppm. In cucumbers, above 8000 ppm, leaf margins incurled and interveinal chlorosis occurred starting from older leaves before the death of the plant. In snap beans, leaves were dark green at the 2000 and 4000 ppm, while at the 8000 ppm older leaves developed severe burn between veins before the death of the plant. In strawberries, severe mar-ginal burn occurred in older leaves and petals were greenish at the 2000 and 4000 ppm. Blossom-end rot occurred to a high degree at the 1000 ppm and above 8000 ppm in tomatoes, and at the 2000 ppm in pep-pers. Broad beans developed no specific symptoms.
4. With increasing concentration of NaCl, the accumulation of Na in leaves increased almost linearly, except in peppers and snap beans, while Cl accumu-lated linearly in any crop. Cl accumulated in leaves in greater equivalent amounts than Na except in broad beans. Antagonistic relations between Na and other cations, i. e. K, Ca, and Mg, varied with ions or vegetables, and the total amount of these four cations in leaves decreased in peppers and snap beans and increased in the others with the increase of NaCl. The variation in the content of N or P was rather slight as compared with cations and was variable with the vegetable species. There was no definite tendency in the contents of carbohydrates.

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In 1953, boron deficiency in Chinese cabbage was found in Kameoka district. In 1955, this physiological disease was severe at many places in Kyoto Prefecture.
The studies on the symptom and the control of this disease were carried out in the Kyoto Agricultural Experiment Station from 1955 to 1958.
1. Brown checking on the midrib of the leaf seemed to be the typical symptom of this disease, and was severe on the 31th to 35th leaves. The time when this symptom appeared was during the heading period.
2. Among the varieties tested, Matsushima group showed the severest symptom, Kaga the second, and Nozaki the third. In Matsushima the boron content was 11.6ppm, and in Nozaki 13.2ppm.
3. The boron deficiency in Chinese cabbage was enhanced when nitrogen and potassium fertilizers and lime were applied in excess. However, in these cases the application of boron caused a normal growth. For prevention from the boron deficiency, it seems desirable to apply 100g of borax per are as the base fertilizer.
4. A severe boron deficiency took place in the case when the precipitation before the heading was only a little, but the deficiency was slight in case of much precipitation.
5. This disease was observed in sandy loam and loam soils with pH 5-6. In these soils the available boron content was 0.09ppm.

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Considerable quantities of the red rooted carrot, Kintoki variety, are grown in the western half of Japan. A search of the existing literature indicated that there has been nothing published dealing with the pigment content of such red rooted carrots.
The carotene contents of the varieties grown in the United States have been reported by many workers (1, 4, 5, 6) but none have included a red rooted variety. FUJITA (2) presented data on pro-vitamin A in vegetables with contents of alpha-, beta-, gammacarotene and cryptoxanthin in carrot root (variety unspectified) as 3, 300, 6, 600, 80 and 60 micrograms per 100 grams fresh weight, respectively. The vitamin A value calculated from his data (13, 800 IU per 100 grams) has been used as the standard of food value of carrot in Japan.
This paper reports the carotenoid contents of Kintoki compared with those of Kokubu, an orange rooted variety commonly grown in Japan.

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The experiments were conducted to clarify the effects of different water-regimes and temperature of irrigation water on the growth of tomato seedlings.
Seeds of “Kurihara” variety were sown in flat. When two or three leaves developed, uniform plants were transplanted to the metal containers on the bench in the greenhouse. The containers were 30×30×10cm in size and were provided with 25 holes on their bottom for drainage. Small gravels were placed 2cm thick on the bottom of each container, and 7.2l of soil was stuffed on it. Ample water was applied to the soils, and after surplus water was completely drained, moisture contents were determined, and they were defined as water capacities (WC). Permanent wilting percentages (PWP) of the soils were determined by BALIR's method using dwarf sunflowers. The soil moisture between WC and PWP was regarded as available water (AW). Compost (volcanic ash soil-1 part : leaf mold-1 part in volume), volcanic ash soil, and sand were used for experiments. Water loss was weighed everyday and, when necessary, a measured volume of water was added to the soil.
1. To set up the plots differing in water-regime, water enough to bring the soil moisture to WC was applied everyday or when 25, 50, 75 or 100% of AW was lost. Growth of the tomato seedlings was markedly affected by the water-regimes in every soil; the most vigorous growth was obtained in the plots in which water was applied everyday, and the drier the soil, the less the growth of seedlings. Growth of the seedlings was closely correlated with the total amounts of water applyed during the experiments. Flower bud developments paralleled to the vegetative growth of the seedlings.
2. Effect of applying limited amount (not enough to bring the soil moisture to WC) of water on the growth of seedlings was tested. Watering the soil to 25 or 50% levels of AW, when 50 or 75% of AW was lost, was compared with the watering to the WC when 25 or 50% of AW was lost. The results obtained, were similar to those of the experiment mentioned above, that is, the growth of seedlings was closly correlated with the amount of water added. This shows that the limited watering which has been prevailing in practical forcing culture of fruit vegetables is unfavorable for the growth of seedlings.
3. Effect of temperature of irrigation water was tested by applying the water differing in temperature (0°, 20° and 40°C) to the tomato seedlings in the plots having narrow and wide water-regimes (100-75, 100-25%). There was no difference due to the water temperature, though significant difference was found due to the water-regime. It is suggested that even if temperature of irrigation water is rather low, it is better for the growth of the tomato seedlings in hot beds to keep, the soil, moist by applying water than to withhold watering.

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There are little published data on the physiolo-gical research of the growth of tulip bulbs throughout the yearly life cycle. In this report, the nitrogen and carbohydrate metabolism and the overall picture of activity of auxins and inhibitors throughout the life cycle are dealt with, especially, those relating to the so-called thermoperiodicity.
BLAAUW, by microscopic observations of the meristem during and immediately after each temperature treatment, distinguished between the direct and indirect temperature effect and identified each optimal temperature with a definite morphological stage.
Each developmental stage has its own optimal temperature; organ initiation needs the highest temperature, stem elongation and unfolding of the flower a lower one, and preparation for elongation, a stage which has no morphological significance, occurs best at the lowest temperature.
1. Fresh weight versus dry weight. Fresh weight of bulbs increases with the progress of the current season's shoot growth. Maximum weight is attained about June 15 in the sandy soil field and about June 25 in the paddy field and thereafter it decreases gradually. Dry weight of bulbs increases in parallel with the increase of the fresh weight and the maximum weight is gained 10 days earlier than the case of the fresh weight.
In practice bulbs are lifted from the ground after they have attained the maximum fresh weight.
Chilling stimulates the decrease of the dry weight but in the chilled bulbs fresh weight decreases less than that of those kept in the room temperature.
Progress of the growth processes of bulbs grown in the sandy soil field proceeds 10 days earlier than that of the bulbs grown in the paddy field.
2. Nitrogenous constituents: Nitrogen content per bulb increases with the increase of the fresh weight and maximum gain is attained later than that of the fresh weight. The percentage of nitrogen content to fresh weight increases also with the progress of the growth process.
Soluble and insoluble nitrogens show similar trends, the former reaching the first peak later than the latter.
In contrast to the bulbs kept in the room temperature, in chilled bulbs the percentage of insoluble nitrogen content to fresh weight decreases and of soluble nitroge increases. In chilled bulbs insoluble nitrogen is accelerated to change into soluble form.
Nitrogen content per bulb and percent content on a fresh weight basis of bulbs grown in the sandy soil field are higher than those of bulbs grown in the paddy field.
3. Carbohydrates: Carbohydrates content per bulb and percent content on a fresh weight basis increases/or decreases with the increase/or decrease of the fresh weight of the bulbs.
Carbohydrates content per bulb decreases gradually. Percent content of fresh weight basis of bulbs grown in the paddy field decreases gradually, whereas that of the bulbs grown in the sandy soil field rather abruptly.
Preceding to the fresh weight, total sugar content (percent of the fresh weight) reaches the maximum and then decreases rather abruptly up to May (bulbs grown in the sandy soil field. about May 25) or June (bulbs grown in the paddy field: about June 15) and then remain constant till the middle of October, whence increases again gradually.
Polysaccharides, having reached the maximum, decrease gradually. Polysaccharides of bulbs grown in the sandy soil field decreased rapidly than those of the bulbs grown in the paddy field. In chilled bulbs, polysaccharides abruptly decreased and total sugars increased abruptly. Polysaccharides are forced to change into sugars by chilling.
Starch is the main polysaccharide and most of sugars is non-reducing.
Starch accumulates initially in the outermost bulb scale, and having reached to the maximum, it decreases. Then it accumulates and decreases successively in the inner bulb scales.
In chilled bulbs, starch in the scale decreases abruptly.

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[in Japanese]

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