Phenoic compounds were separated with chromatographical and chemical techniques from extracts of Japanese pear tissue. And they were identified as arbutin, chlorogenic acid, chlorogenic acid isomers, caffeic acid, quinic acid, catechin and its isomer.
The young leaf contained more amount of arbutin, caffeic acid and quinic acid than old one, but did not contain catechins. Much amount of chlorogenic acids were contained in the leaf without any distinction of its age.
Infecting with host-specific toxin produce dby the fungus, the young leaf of susceptible variety (Nijusseiki) has been browned at a short time and decreased the content of arbutin and chlorogenic acid. On the other hand, the young leaf of resistant variety (Chojuro) remained green upon the same product treatment and no effect on the content of those phenolic compounds.
Reacting the phenolic compounds with polyphenol oxidase extracted from the young leaf of susceptable variety, arbutin and chlorogenic acid were oxidized and browned immediately.
So from above results, authors believed that arbutin and chlorogenic acid may have close contact with brown of the leaf infected with that metabolic product.

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1. Changes in nitrogen and carbohydrate contents in hardwood cuttings of grapevines (cv. Delaware) were investigated during propagation.
2. Dry weight of a whole cutting continued to decrease gradually through 60 days after planting and thereafter began to increase due to the growth of new shoots. The increase of dry weight in upper and lower half stems indicated that the newly photosynthesized matters in new shoots began to be translocated into the originalstems.
3. The soluble-nitrogen content (% dry weight) gradually decreased in both upper and lower half stems throughout the propagation period. While, the insoluble-nitrogen content decreased markedly only in upper half stems as the new shoots grew. The trend of total-nitrogen content was very similar to that of insoluble nitrogen content.
4. Distribution ratios of soluble-, insoluble-, and total-nitrogen in upper and lower half stems lowered rapidly as the new shoots and new roots developed. Eighty days after planting, the distribution ratio of total-nitrogen in new shoots, upper hlaf stems, lower half stems and new roots became 32%, 32%, 33%, and 3%, respectively. These values showed that a considerable amount of nitrogen moved from the lower parts to the upper parts of the cuttings.
5. Little differences were found in the contents (% dry weight) of starch, sugars and total carbohydrate between upper and lower half stems. The starch content generally decreased in both parts throughout the propagation period, while the total sugar content showed a marked decrease through 40 days after planting, followed by a temporary increase.
6. The decrease in the total carbohydrate content, which was more markedly in lower half stems than in upper half stems, was due to that of the sugar content. Between 40 and 80 days after planting, the contents of total carbohydrate and starch in upper half stems remained unchanged or increased slightly.

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Induction of parthenocarpy in Japanese cultivars of the peach was demonstrated. Among several growth regulators examined, GA₃ was only effective to induce parthenocarpic fruit in Okubo cultivar, when it was applied at a concentration of 500 or 1000ppm at the balloon stage. Moreover, GA₃ was effective to induce parthenocarpy in 3 of the 6 cultivars tested, but had no effect on the ramaining 3 cultivars.
It was also found that the percentage of parthenocarpic fruit set increased with increase in a concentration of GA₃, and higher percentages of parthenocarpic fruit set were obtained in repeated applications of GA₃.
No effects were obtained in the growth of parthenocarpic fruit for three concentrations of GA₃ when it was applied only once at the balloon stage, but pronounced effects were found in parthenocarpic fruit growth when GA₃ was applied repeatedly during the early stage of fruit growth, even if it was applied at a low concentration.
Fruit quality of parthenocarpic fruit induced by GA₃ was almost identical to those of pollinated fruit, although fruit size and weight were smaller than the pollinated fruit.
It was also shown that non-pollinated peach fruit will continue their further growth when GA₃ at a concentration of 1000ppm was applied within 30 days after emasculation, but not thereafter.
Morphological observations showed that there were little or no differences in mesocarp thickness between seeded and parthenocarpic fruits, although some differences in cell number and cell size were found between them. While, tissue thickness of pits and pit cavity in the parthenocarpic fruit were smaller than those of the seeded one.

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1. The photosynthetic activity was compared among several kinds of fruit trees and grape vines in relation to some environmental factors. The rate of photosynthesis was determined with intact leaves remaining on potted trees by means of an infrared CO₂ analyzer.
2. Photosynthesis was considerably influenced by the rate of air movement. Maximum photosynthetic activity was observed at the air flow rate of about 1 liter/dm²/min in peaches, grapes and chestnuts, while in Japanese persimmons, figs and satsuma mandarins, it was 2 liters/dm²/min. The rate of photosynthesis of the former group began to decline when the rate of air movement became higher than optimum. In the latter group, however, there existed no such evidence.
3. Saturating light intensity for the photosynthesis of intact leaves was approximately 40klux in Japanese persimmons, figs, peaches, chestnuts and satsuma mandarins, and 30klux in grapes.
4. Satsuma mandarin trees were grown in various light intensities between 8 and 100klux. The thickness of leaf blade and palisade parenchyma, number of stomata per mm² were all decreased with lowering light intensities, whereas leaf areas increased.
5. Optimum leaf temperature for the photosynthetic activity was about 25°C in grapes, figs and satsuma mandarins, 30°C in peaches and 20°C in Japanese persimmons and chestnuts. At higher temperatures than optimum, the photosynthetic activity was decreased rapidly with increasing leaf temperatures in Japanese persimmons, figs, peaches and chestnuts, but in grapes and satsuma mandarins it was lowered gradually.

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1. Using three-year-old fruiting Satsuma orange trees, the effects of summer soil moisture (pF 2.3, 4.0) and time of fall nitrogen application (September-, October-, November-. and Non-application) on the fruit quality and flowering in the following year were observed.
2. Coloring of fruit rind was superior in the plot of pF 2.3, and the later the time of nitrogen application, the better was coloring of the rind. On the contrary, it was markedly delayed in the plot of pF 4.0 with September application of nitrogen.
3. Contents of soluble solids and total sugars in fruit juice were higher in the plot of pF 4.0 than those of pF 2.3, and were also much higher in the trees with a delayed nitrogen application. There was no difference of citric acid content among the experimental plots.
4. The number of flowers in the following year were very great in the plot of pF 4.0, and were also increased as nitrogen was applied early. On the contrary, new shoot growth was inferior in the plot of pF 4.0.
5. The content of nitrogen in the spring leaves was increased with fall nitrogen application, especially in the plots of September and October application.

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In order to clarify the effect of application of various amounts of phosphate in combination with lime to the soil on the growth and fruiting of young Satsuma mandarin trees, field experiments were carried out for ten years from 1960 to 1970, in the orchard of diluvial clayey loam.
1. The growth of new shoot and trunk, and the increase in leaf number were accelerated by the application of lime until 1962 when the tree sizes were comparatively small The effect of applied phosphate was found only in the plots without lime, that is, the development of trees was accelerated as the amount of applied phosphate was increased. These trends were observable in 1963, but significant differences have disappeared since 1964.
2. Since 1963, a similar symptom that was caused by calcium deficiency was found on twigs and leaves of trees in the plots without application of lime, and defoliation and twig dieback occurred in 1964 and 1965. These trees gradually recovered since 1968.
3. The number of flowers of P₀ plot in 1964 was distinctly low, and this was recovered by an application of phosphate. Since 1965 no significant differences in yield among the various plots were found, although a slight low yield was found in P₀ and P₁ plots in 1964.
4. During five years from 1964 to 1968, there were no substantial differences in fruit weight among the plots. A slight difference was found in 1969, but this might be due to a difference of the number of fruits per tree.
No significant differences were also found in fruit color and rate of fruit rind among the individual plots. Total sugar content in fruit juice was slightly low in the plots of phosphate deficiency. It is notable that citric acid content was distinctly lowered by an application of lime. The amounts of applied phosphate did not affect the content of citric acid. Sugar acid ratio was substantially high in the plots treated with lime, which is resulted from lower values of acid content caused by lime application.
5. There were not so much differences in phosphorus content of leaves among the plots which received various amounts of phosphate. However, the plots which received lime showed clearly higher values in calcium content of leaves than those which did not receive lime. Magnesium content was higher in the plots which did not receive lime, its content was decreased by increasing the amount of applied phosphate.
6. The content of available phosphorus in the soil was increased in proportion to the amount of applied phosphate. The contents of available phosphorus at 30-cm depth were less than half of those at 10-cm depth. Exchangeable CaO, degree of calcium saturation and pH of the soil were very high in the areas which received lime. Those values in the plots which did not receive lime were increased by increasing the amounts of applied phosphate.

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1. This investigation was made for clarifying some differences which controlled the manganase content in new mature leaves (3-month-old) of Satsuma orange trees grown on soils having fairly low available manganese.
2. One-year-old shoots with new and old leaves were collected at flowering period and green mature stage from 10 trees growing in 5 groves at Yugawara region of Kanagawa Prefecture. Hitherto they had not been suffered from the manganase deficiency. In Ito region of Shizuoka Prefecture, old leaves were collected before bud break and at flowering period from 16 alternative fruit bearing trees, which showed the manganese deficiency symptoms on the new leaves of“off”year trees at their green mature stage. New flushes were collected at flowering period and their green mature stage from above trees, and fine roots were dug out from 3 places at the drip region of each tree.
3. From flowering period to green mature stage of new leaves, both manganese contents of new and old leaves on healthy trees increased significantly, and a significant positive correlation existed between the manganese contents of new leaves at 3-month-old stage and those of old leaves at 15-month-old stage.
4. Before bud break of first flush of growth cycle, the difference of manganese contents of old leaves on“off”year tree and“on”year tree was not found, but the significant difference was found in manganese contents of new 3-month-old leaves from above trees.
5. At flowering period, differences in distributed percentages of absolute manganese contents in each part on 1-year-old shoots of“on”and“off”year trees were found only in the composition of new organs, but was not found in the rate of “old”and“new”part.
6. Growth in fine roots in unit soil volume at the drip region of trees which had heavy crop load in previous year was less than that of the trees which had light crop load.
7. These results confirmed that manganese contents of new mature leaves are controlled by soil available manganese contents, rates of growth of new flush to old flush, and volumes of fine roots which were affected by different crop loads in the previous year.

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The contribution of several factors affecting the total soluble solids and free acid content of satsuma fruit was estimated by the quantification method. The orchard location gives the greatest contribution to both the refractive index and total acidity of flesh juice. As for the total soluble solids content, the contribution of slope exposure ranks second, followed by tree age. In general, the refractive index of the juice increases slightly but consistently with increase in tree age. Altitude and distance factors exert less effects on the solids content than the other factors.
On the other hand, the total acidity of the juice increases considerably as the grove departs farther from the coast line. As for the altitude, the acidity increases outstandingly at higher levels than 200 meters above the sea, though at lower levels than this limit it is scarcely influenced by altitude. Exposure of the slope exerts somewhat irregular effects on both solids and acid content of the juice.

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In the previous paper, it was shown that the growth of flowers of tomato plants exposed to lower temperatures were prominently invigorated and much more locules were formed, and such responses in tomato flowers may be attributed to surplus nutrient supply to young flower buds.
This paper reports the results of the study on the effects of light intensities and soil fertilities on the development of tomato flowers, especially that of the ovaries and their locules.
Tomato seedlings were grown at four different light intensities (100, 75, 50 and 25 per cent of natural day light) and at three different levels of soil fertilities.
The lower light intensities and or the poorer soil fertilities retarded the morphological development of flowers and hence resulted in forming smaller flowers with smaller sepals, petals, anthers, and ovaries.
The flowers of the plants grown under natural day light condition and/or fertile soil condition developed most remarkably, and their ovaries attained the highest size, and their sepal and locule numbers highly increased. The flowers of plants grown at lower light intensities and/or in poorer soil fertilities less developed and their sepal and locule numbers were fewer.
These results suggest that the seedlings grown at lower light intensities were at lower levels of carbohydrates, and the ones grown in the soil of lower fertilities were at lower levels of nitrogenous and phosphorous constituents in the whole tomato plant, and poorer flower development in such cases may be attributed to restricted nutrient supply to young flower buds.

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Keeping the quantity of the endogenous growth substance in stem segments (4mm) of Portulaca grandiflora and Mesembryanthemum spectabile as less as possible, the experiment was carried out to test how morphologically the exogenously applied IAA, kinetin and their combination had effects on root formation, bud formation and callus formation.
1. In M. spectabile, root formation and bud formation were promoted by IAA treatment under light codition. Root formation was inhibited by IAA treatment under dark condition, but bud formation was promoted by IAA treatment under dark condition.
Root formation and bud formation were inhibited by kinetin treatment under light condition. Root formation was inhibited by kinetin treatment under dark condition, but bud formation was promoted by it under dark condition.
In P. grandiflora, both root formation and bud formation were not affected by IAA treatment.
2. In M. spectabile, a combination of IAA and kinetin showed more promotive effects on root formation, bud formation and callus formation than IAA or kinetin alone. Especially root formation was promoted by a combination of 10ppm IAA and 0.1-0.01ppm kinetin under light condition, and bud formation was promoted by a combination of 10ppm IAA and 1ppm kinetin under light condition.
In P. grandiflora, root formation was promoted by a combination of 10ppm IAA and 1ppm kinetin under dark condition.
3. Root formation in pith was promoted by a combination of 10ppm IAA and 0.1 ppm kinetin undr light condition.
Bud formation of cortex was promoted by a combination of 1ppm IAA and 0.5ppm kinetin under light condition.
4. Casein hydrolysate or Yeast extract put into the medium had not affects on both root formation and bud formation.

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A possibility of the application of the cultural technique in vitro for the isolation, fixation and propagation of the mutant plant from sectorial mutation induced by gamma irradiation on Begonia rex has been investigated.
The variety‘Winter Queen’was employed throughout all the experiments. The mature leaves from stock plants were removed and cut into small leaf fragments approximately 3mm×3mm in size. The fragments were sterilized by 3% antiformin and washed with sterilized water. The sterilized leaf fragments were planted horizontally onto the White′s agar medium aseptically and cultured in the plant growth cabinet at 25±2°C, 40-50% relative humidity and 3000lux illumination for 11 hours a day.
After a month of culture in vitro, adventitious buds arose from the leaf fragments (Fig. 1). The adventitious buds in tubes grown to 0.5mm in length were irradiated with 10krad of γ-ray at dose rate of 0.2krad/hr. After the irradiation, the tubes were placed again in the same cabinet and the leaf fragments cultivated for another 3-4 months. Then, the buds were grown until the young plants produced several leaves. Two of the thirty young plants produced the chimeric variegations on their leaves (Table 1). Then, these two plants were transplanted to water culture bed in green house and cultivated for 6 months. The apperance of the plant cultivated for 6 months is shown in Fig. 3 for comparison with the normal plant. As shown in the figure, the leaf of chimeric plant has the sectors of green leaf color with silver white spots. Whereas, the original leaf color of‘Winter Queen’is covered with silver white.
For the isolation and fixation of this somatic mutation, the sector of the leaf was cut into leaf fragments approximately 3mm×3mm to 5mm×5mm in size, and these fragments were planted onto White′s agar medium. The fragments were cultured under aseptic conditions for 4-5 months in vitro. After a month, the adventitious buds arose from the leaf fragments cultured and grew to young mutant plant after another 4-5 months of the culture. Among these plantlets, three sound plants were transplanted to flower pots in the water culture bed in green house.
These new plants propagated from the mutant sector were changed wholly in leaf color as that of the sector. The appearance of the changed plant and that of the leaf are shown in Figs. 4 and 5, respectively.
Some histological explanations on the development of wholly changed plant from leaf fragment were presented.
The procedures of these experiments are illustrated in Fig. 6.
From this investigation, it is suggested that the adequate combination of irradiation and of in vitro culture will be useful in the breeding of the horticultural crops.

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Changes in the peroxidase activity and the gel-filtration pattern with Sephadex G-200 in the pulp and peel tissues of apple fruits stored in the controlled atmosphere (CA) and the conventional refrigerated room were investigated.
The remarkable increase in the total activity was recognized in the pulp tissues of “Jonathan”and“Starking Delicious”apples stored under the CA condition. However, in other varieties the activities were held at almost same level during the CA storage, and also similar results were found in all varieties stored in the refrigerated room. On the other hand, the activities in the peel tissues of all varieties increased under the both storage conditions.
The gel-filtration patterns on the activity in the protein fraction prepared from the pulp and peel tissues of apple fruits were composed of three fractions which were designated as fraction I, II and III except“Mutsu”variety which showed only two fractions, fraction II and III. It was not clear that, these differences were caused either by the maturity at which the fruit was harvested or the variety.
The activity which increased in the pulp tissue of“Jonathan”stored under the CA condition was found in the fraction II, and the sum of the activity of the fraction II amounted to about 96% of the total activity.
There were no significant differences in the pattern between apples stored under CA and cold condition.

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Mature Satsuma oranges (Citrus unshiu Marc.) were harvested on November 27, 1968 and were stored at various temperatures and 80-90% R. H. Decaying condition and respiration of fruits, changes in sugar, acid and ascorbic acid concent of juices, were studied during and after storage.
1. At 20°C, the decay by stem-end rot increased rapidly after 60 days of storage, and marked shriveling appeared on the peels of fruits. Although the fruits stored at 10°C maintained its keeping qualities for a longer period (120 days), eventually the shriveling and stem-end rot occurred. At lower temperatures, 2°C and 5°C, the decay by penicillum mold increased rapidly after 120 and 160 days of storage, respectively. The shriveling of peel could not observed in the fruits at the both temperatures. The fruit at 2°C, however, showed symptom of chilling injury from the middle of April, and objectionable graying developed on the peel.
At 2°C, a pronounced decrease in respiration occurred soon after the beginning of storage, and the low respiration level remained constant until the increasing time of decay, when a slight increase in respiration took place. The same pattern of respiration was observed in the other cases.
In below 6°C, ascorbic acid and sugar concentration of juice, which extracted from fruit, remained approximately the same as in the fruit before storage, but total acids concentration and sugar concentration decreased remarkably even in undecayed fruit at the end of storage period as compared with those of fruit stored low temperature.
At 2°C, evolution of volatile substances from the fruits increased pronouncedly with the development of chilling injury, and those fruits were always accompanied with the rise of respiration.
2. CO₂ production of fruits transferred from 2°, 6° and 10°C increased for the first 8-12 hours after transfer to 20°C and then decreased, and it was evident that there was a cumulative time-temperature influence of chilling exposure upon the degree of stimulation in CO₂ evolution.
The low temperature during storage resulted in the notable decrease of chemical compositions in fruit juices after transfer to 20°C.
Naturalization, in which the temperature of fruits rised gradually, prevented the rapid rise of respiration. And also, number of decayed fruits and decrease of chemical compositions of fruits in this treatment were more less than those of fruits transferred directly to 20°C.

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The experiments were carried out to clarify the effects of carbon dioxide concentrations on natsudaidai fruits and to determine the optimum carbon dioxide levels in CA storage. The fruits were stored in the air mixed with 0, 3.3, 16, 25% carbon dioxide at 4°C for 49 days and 0, 3.5, 13, 23% at 20°C for 33 days in 1970, and in 1971, 0, 2.5, 5, 10, 15, 20% at 4°C and 20°C, for 66 days and 37 days, respectively. Excluding the effects of low oxygen concentrations, oxygen levels were kept at high levels (15.8-21.0%) in each treatments.
1. At 4°C, the browning of buttons was retarded above 5% CO₂ in 1971. No distinct differences were found among CO₂ levels in soluble solids, but the reduction of titratable acidity was accelerated at 25% CO₂ in 1970.
The peel softened, and then, the albedo turned watery and yellow, and the juice sac turned from orange color to yellow above 10% CO₂. The injured fruits had high peel fresh weight and high peel ratio to whole fruit by fresh weight basis, and developed the fermented flavor and the strong bitter taste. The higher ethanol contents were found in the fruits with the fermented flavor and the strong bitter taste. The flat taste and the slight granulation were found below 2.5% CO₂ in 1971, so the best eating quality was obtained at 5% CO₂. Pitting was reduced above 5% CO₂.
2. At 20°C, the browning of buttons was retarded above 3.5% CO₂ in 1971, and above 5% CO₂ in 1971. No distinct differences were found among CO₂ levels in soluble solids and titratable acidity. The abnormal flavor and the slight sweet taste developed above 13% CO₂ in 1970, and above 5% CO₂ in 1971. The fermented flavor, the strong bitter taste and the accumulation of ethanol were not found in all treatments. Above 13% CO₂, the peel color turned reddish.
3. Under high CO₂ levels in citrus CA storage, three problems viz., the decay, the abnormal flavor and the puffy fruit with the plumping peel (ukigawa), must be solved. The humidity control seemed to be one of the important storage problems to be studied. In natsudaidai fruits, the optimum CO₂ level was 5% at 4°C. The discussion was made about the abnormal flavor and the strong bitter taste in relation to the high water contents and the gas diffusion resistance of the peel, the internal gas concentrations and the ethanol accumulation.

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In previous report it was suggested that peas and broad beans should be held at strictly low temperature immediately after harvest to keep the quality. Present study was carried out to investigate the time-temperature tolerance of these materials for keeping the taste and to find out the factors concerning deterioration of taste. Peas and broad beans with pods were packed in perforated polyethylene bags, and treated at 1°C, 6°C and 20°C with scheme shown in Fig. 1.
1. Organoleptic test showed that the taste of peas markedly deteriorated in a day at 20°C. Even at 6°C the deterioration was considerably rapid and the difference from 1°C-storage was detected 5 days after. Delayed cooling, transferring to 20°C from 1°C-storage, and fluctuation between 1°C and 6°C resulted in hastening of deterioration in comparison with steady 1°C-storage. With broad beans, such tendency was approximately the same as peas.
2. While total sugar content of peas and broad beans showed some increase at 1 °C, it decreased markedly at upper temperatures, i.e., the content became a half or a quarter of initial in a day at 20°C, about a half in 2 days at 6°C and 10°C. Transferring to 20°C from 1°C resulted in rapid decrease. Fluctuation between 1°C and 6°C showed the value between steady 1°C and steady 6°C, then gradually reached to the level of 6°C. When the materials were transferred from 20°C to 1°C, the sugar content which had once decreased was recovered to the extent of steady 1°C, however, in taste test significant recovery was not observed.
3. Neutral and acidic amino acids were determined using TLC and automatic analyzer. Threonine, glutamic acid, alanine, valine, iso-leucine, leucine, tyrosine, phenylalanine and other ninhydrin-positive products were detected in both peas and broad beans at harvest. They decreased drastically at upper temperatures. For example, alanine which was found abundantly in both materials decreased by 1/12 in peas and 1/5 in broad beans in 2 days at 20°C. At 1°C the decreasing rate was slowed down considerably, but 6°C of storage temperature was insufficient to prevent the rapid change.
4. Sucrose-U-¹⁴C and alanine-U-¹⁴C were applied by vacuum infiltration to the slices of broad bean cotyledons and incubated for 10 and 24 hours at 20°C. They were incorporated rapidly into alcohol-insoluble fractions, presumably starch from the sucrose and protein from the alanine. Incorporation into alcohol-soluble cationic and anionic fractions was also observed to some extent.
5. Hardening of cotyledons took place rapidly in both materials at 20°C. At 1°C the texture was kept soft for considerable period. Hardness of cotyledon measured by Curd meter paralleled with organoleptic test to considerable degree with peas, however, good correlation was not obtained with broad beans.
6. It is concluded that three factors as decrease of sugar and amino acid contents and hardening would largely concern with the rapid quality deterioration of peas and broad beans. For keeping the quality, strictly low temperature is needed.

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