The experiment was conducted to investigate the affinity of grafting of fruit trees by means of in vitro callus culture.
Kinetin, NAA and IBA accelerated the callus induction from cambium of the stem section.
Kinetin enhanced the effect of auxins, e.g. NAA and IBA, on initial callus induction. On the other hand coconut milk had no effects on initial callus induction.
Coconut milk was a suitable addition for a long term cultivation of callus tissue.
The shape of callus cells and the strength of cell union were varied by some additions in the medium.
Adventitious roots were formed from grape callus on the medium with NAA, IBA, and kinetin. In all materials no bud formation occurred.
Two different callus tissues were grafted vertically and horizontally and four grades were established to determine the degree of callus fusion.
In some combinations callus fusion occurred rather differently from the description in taxonomy.
Callus fusion between rootstock and scion for successful grafting should be one of the most important factors, but there might be some other factors for the completion of grafting.

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It has been proposed that use of Bordeaux mixture for disease control in Japanese apple orchards be discontinued in order to reduce labor costs. However, it was found that, without Bordeaux mixture, Jonathan apples were severely affected with several kinds of physiological disorders such as Jonathan breakdown and Jonathan spot. A preliminary experiment in 1965 showed that calcium element of Bordeaux mixture had the effect on control of these disorders. In the 1966 and 1967 growing seasons, experiment were made in commercial orchards (M, S and T) and our research station′s orchard (J) to confirm these results. In this paper, the effect of calcium chemicals applied as CaCl₂, lime water (Ca component of Bordeaux mixture), or Ca(NO₃)₂ on the occurrence of Jonathan breakdown was examined.
Each calcium chemical was sprayed to whole trees with a gun sprayer in July and August or in September. Details of treatments were shown in Table 1.
Two kinds of flesh browning disorders were found during this experiment on Jonathan fruits; Jonathan breakdown (Fig. 1) and an unknown flesh browning disorder (Fig. 2). Neither disorder was typical of low temperature breakdown.
The incidence of Jonathan breakdown was reduced by all calcium sprays. However, the effect of lime water varried among orchards more than that of CaCl₂ (Table 2). In common storage, breakdown increased rapidly until January. The disorder occurred slowly during this time in fruits treated with any of the calcium sprays, but after January, it occurred at the same rate in all treatments (Fig. 3).
The incidence of the unknown flesh browning disorder was not reduced by calcium sprays applied in July and August, but was reduced by the CaCl₂ sprays in September (Table 4).
Sprays of calcium chemicals, including lime water, increased the calcium content of the peel and flesh of mature fruits (Table 5). Fruits affected with Jonathan breakdown were significantly lower in calcium than normal fruits. Phosphorus, potassium and magnesium tended to accumulate in the flesh of affected fruits (Table 6).

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To determine the effect of calcium sprays on the occurrence of Jonathan spot and the related spotting disorders, CaCl₂, lime water or Ca(NO₃)₂ were sprayed to Jonathan apple trees 4 times in July and August or 2 times in September (CaCl₂ only). The concentration of each chemical applied was; CaCl₂…0.38%, lime water…1.2% as CaO, and Ca (NO₃)₂…0.5%. Details of treatments were shown in Part I of this series of report.
The incidence of Jonathan spot was reduced by the sprays of CaCl₂, lime water and Ca(NO₃)₂ as shown in Table 1 and 2. Lime water was the most effective in controlling the disorder, CaCl₂ was next, and Ca(NO₃)₂ was least effective.
The calcium content of the peel of fruits from the lime treatment was not higher than that of the CaCl₂ treatment (Fig. 2). Generally, the incidence of Jonathan spot was relatively low in fruits where the calcium content of the peel was high. However, disorder incidence did not always increase as the calcium content decreased (Figs. 2 and 3). These results suggest that Jonathan spot is not a simple calcium deficiency disorder. The incidence of Jonathan spot in M orchard was exceptionally severe as compared with other orchards (Table 2). In M orchard, K/Ca ratios of the leaves, fruitlets and mature fruits tended to be higher than in any other orchard (Table 5).
We classified the spotting disorders of the surface of Jonathan apples into two main types; Jonathan spot and Jonathan freckle according to Heald (6). Additional spotting disorders other than these two main types were found in this experiment, and were also controlled by the sprays of calcium chemicals (Tables 3 and 4). As in the case of Jonathan spot, lime water tended to be the most effective for these disorders. The results of Jonathan freckle were not shown, as this disorder scarcely occurred one month after harvest, the period of this experiment.
Fruit spot caused by a fungus (Mycosphaerella pomi) were also reduced by the sprays of lime water and CaCl₂ (Table 6).

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1. Studies were made on the translocation of photosynthates using a tracer technique. The radioactivity was measured by a cintillation counter.
2. It was proved that a summer cycle shoot was a powerful sink and a large amount of ¹⁴C was translocated to the part. When it was detached, somewhat higher activity of ¹⁴C was observed in the underground part of the tree.
3. In increasing fruit number per tree, total activity of ¹⁴C in the fruit part was increased but the activity per ml of juice or unit weight of plant parts was lowered. Basipetal movement of ¹⁴C was also decreased with much fruiting.
4. Application of GA₃ or kinetin solution on fruit surface, increased the movement of photosynthates into the fruit. While the application of CCC depressed the translocation of photosynthates. The ¹⁴C in the juice might be mainly originated in sugars translocated from the leaves.

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There are few reports that leaf color is related to physiological conditions of Satsuma orange trees. The present paper deals with relationship between chlorophyll content and strains of Satsuma orange trees, seasonal change of its content, and effects of light intensity and nitrogen on its content.
The chlorophyll content of Usami was 15mg per g dried weight, this strain contained the highest of the strains in this experiment. Sugiyama, Hayashi, Silverhill, Ishikawa, Yakushizi, Aoshima, Katayama, Miyagawa-wase and Okitsu-wase were 7-9mg, these strains were moderate. The strains of Oiwa No.5 and Zyuman were 5mg, these strains contained the lowest of them.
Satsuma orange trees had less chlorophyll content in the early season (January to June) than the late season (July to December) in the leaves. The leaves, exposed to sunlight in all seasons, had less chlorophyll content than shaded leaves on the same tree.
The chlorophyll content in exposed leaves decreased in winter, but this phenomenon was obviously stopped by enveloping with straw-mats or cheese cloth on the tree.
The more amount of nitrogen was fertilized to trees, the more contents of nitrogen and chlorophyll were increased. And there was a high positive correlation (γ=+0.95) between total nitrogen and chlorophyll content in the leaves. But when the total nitrogen content exceeded 3.5 percent in the leaves, chlorophyll content did not increase.

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As previously reported, fruit drop by Peach-thin is over about 25 days after full bloom, and final hand thinning is used to be done about 30-40 days after full bloom. This report concerns the fruit drop during the period between the end of drop by Peach-thin and the final hand thinning.
1. The experiments had been conducted on three groups of peach trees (cultivar Hakuho); Group one was consisted of 4 trees of 13-16 years old during 1962-1965, group two 3-6 trees of 4-7 years old during 1962-1965, and group three 4-8 trees of 4-7 years old during 1967-1970. In every season, 200ppm solution of Peach-thin was sprayed two or three days after full bloom. In addition, twice spraying of 200 ppm solution two and four days after full bloom and 400ppm spray two days after full bloom, were applied in some cases. As the results of these experiments, significant differences were not found in the amount of the drop in this period between Peach-thin sprayed branches and unsprayed branches, and between the tree ages ranging 4-7 years old, while the amount of drop varied with the years. Therefore, it may be concluded that the drop during this period is neither affected by Peach-thin spraying nor by tree age, but is affected by the climatic conditions of the year. Throughout these experiments, the range of fruit drop rate was from 0% to 25%, and the population mean was 10.7±1.5% at the 95% confidence coefficient. As proper fruit setting at the hand thinning time is 16-18%, desirable fruit set at the end of drop by Peach-thin spraying may be 26-28% (approximately 25-30%), when the amount of drop in this period is expected to be about 10%.
2. All the flowers, which were cut off their styles at their bottom in their full bloom in order not to be fertilized, dropped during the period from 25 days to 40 days after the full bloom. Therefore, it is assumed that the drop in this period may be the drop of fruits which did not have chance to be fertilized. A part of fertilized fruits seems to be thinned by Peach-thin spraying.

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In order to avoid the CO₂ depletion within the canopies, tomato and cucumber seedlings were grown in winter under condition of supplementary CO₂ or under air movement in raising room.
Supplementary CO₂ was applied with pure CO₂ from a cyclinder at the definite flow rate and CO₂ concentration was controlled at 1, 300ppm by means of a solenoid valve connected with an infrared gas analyser and setting box. An air movement was achieved by operating two air circulating fans so as to move inside air horizontally. These treatments were begun about 30 to 40 minutes after the, sunrise and concluded ventilation and continued every morning during raising period.
The air movement reduced significantly the CO₂ depletion within the plant canopies. The critical wind velocity for maintaining CO₂ level within 90 per cent of the ambient was 50cm•sec^-1 over the plant canopies.
Plant height and leaf area were considerably decreased by the air movement both in tomato and cucumber. These were associated with a gradual increase in the difference between leaf dry-weight per area, fresh- and dry-weight percentage, for air-moved and control plants, showing an increase in leaf thickness and in higher transpiration rate for air-moved plants.
In general, the air movement increased their net assimilation rates, but decreased relative growth rates and leaf area ratio for tomato plants. A considerable increase was found in the mineral contents of air-moved plants, such as nitrogen, potassium and calcium, represented as dry weight basis in tomato and cucumber leaves. Consequently, the air-moved plants had relatively less yields early crops.
On the contrary, CO₂ enrichment for young tomato and cucumber plants increased significantly fresh-and dry-weight, leaf area, and leaf dry weight per area. Extra CO₂ also increased net assimilation rates, initially relative growth rates and relative leaf growth rates for tomato plants. Leaf area ratio, on the other hand, was slightly decreased by supplementary CO₂, although the downward ontogenetic drift was observed both in enriched and control plants.
Effects of supplementary CO₂ on the growth of tomato plants were more remarkable when extra CO₂ was applied to their younger stages. Extra CO₂ was less effective for the growth of cucumber plants grafted on Cucurbita ficifolia, although early yields were significantly increased. Mineral components in the leaves of tomato and cucumber were not markedly affected by CO₂ enrichment, while their amounts were greatly increased as a result of increased dry weight.
CO₂ enrichment increased early marketable yields by 15 and 18 per cent for tomato and cucumber respectively. This is certainly because of larger fruits harvested from lower trusses of enriched tomato plants.

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In the first experiment, tomato plants were grown under the plastic-house in which the air was ventilated by operating the ventilating fans through the mouth piece fitted at the opposite side of the fan. Thus, there were considerable horizontal gradients for temperature, wind velocity and CO₂ concentration from the inlet to the outlet of ventilating air over 46 meters in depth.
When the wind velocity decreased to 20-30cm•sec^-1, remarkable CO₂ depletion was observed within tomato canopies. An air temperature increased noticeably with increasing the distance from the inlet. And maximum temperature gradient was in the order of 5°C at incident solar radiation of 8 kcal. m^-2 min^-1 at the end of May.
Early yield of tomatoes was considerably decreased by heavy wind velocity near the inlet of ventilating air. Tomato fruits harvested from the poor-ventilated plants, however, had less titratable acidity, soluble solids and ascorbic acid. Moreover, these fruits had high respiratory rates at their post-harvest stage. In general, the titratable acidity and soluble sugar contents in the tomato fruits continued to decrease over whole harvesting period. Such a decrease of acid and sugar contents was more remarkable in the fruits harvested from the poor-ventilated plants.
On the other hand, well-ventilated plants showed higher values of leaf dry weight per area, fresh- and dry-weight percentage and lower values of internodes length. Photosynthetic activity of the leaf sampled from well-ventilated plants was significantly higher than that of poor-ventilated. While, respiratory rate of the leaf was higher in the poor-ventilated plants, although Q₁₀ value seemed to decline for the plants grown under condition of higher day temperature. Chlorophyll content was also largely affected by the ventilation. Poor-ventilated plants had leaves with lower chlorophyll a and higher chlorophyll b contents. So, the ratio chlorophyll a to chlorophyll b was considerably decreased in the poor-ventilated plants.
The second experiment was carried out to estimate the favourable air volume for the ventilation from practical point of view, as much as to supply CO₂ for sufficient photosynthesis and to decrease the temperature gradient.
Efficiency of photosynthetic activity for tomato plants increased linearly with increasing ventilation rates, then passed through transition ranges and finally became almost independent of the ventilation rates. This critical rate seemed to be in the order of 40 times for room space volume per hour. The efficiency of photosynthetic activity was also affected by leaf area density, showing lower efficiency at higher densities. Photosynthetic activity of tomato leaves was increased with increasing wind velocity up to the order of 50-90cm•sec^-1, and further increases in the wind velocity decreased slightly the photosynthetic rates,
Temperature gradient between outside and inside of plastic-house was measured by changing the ventilating air at three light intensities. These results suggest that air volume 140m³. 100m^-2. min^-1, wind velocity 30cm•sec^-1 inside the canopies or 50cm•sec^-1 over the plant top and ventilation rates of 30-40 times per hour were necessary for sufficient ventilation, both for C0₂-transport and temperature decrease.

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It was shown in our previous report that abnormal chlorosis of leaves in Baker′s garlic plants (Allium bakeri Regel) at Fukube Village, County of Iwami in Tottori Prefecture was caused by zinc deficiency. Experiments were made to find effective sprays to correct garlic zinc deficiency. Results obtained were summarized as follows:
1. Foliar sprays of zinc sulfate, zinc chloride, and Zn-EDTA were markedly effective for the reduction of chlorotic symptoms and resulted in normal growth and good yields. There were little differences in effect among sprays of zinc materials; zinc sulfate, zinc chloride, and Zn-EDTA.
2. After the occurrence of chlorotic symptoms, the earlier the time of application, the faster the chlorotic symptoms disappeared. Such a treatment resulted in normal growth and good yields.
3. Zinc deficiency of Baker′s garlic plants can be corrected with 3 sprayings of 0.3 per cent zinc sulfate at the rate of 10 liters per are of fields every fifth day.

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Organ formation has been studied with lateral buds excised from bulbs of Iris hollandica cv.‘Wedgwood.’The buds were cultured in vitro on the medium of modified Kano, Neergarrd and Morel. Adventitious bud formation of explants was induced on the medium containing both NAA and BA, but root formation was suppressed. Root formation was observed on the medium containing NAA alone as a plant growth regulator. High concentration of mineral salt favoured the growth of explants, and better results were obtained on the medium based on Morel or modified Kano. Peptone added into modified Kano′s medium inhibited the growth of explants at 2g/l and higher concentrations. The growth of explants was good at pH 5.0 and 6.0. The optimal concentrations for agar and sucrose were 2g/l and 2-4%, respectively.

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The callus used in this study was obtained from the shoot apices culture and has been subcultured every thirty days for over two years on Murashige and Skoog′s agar medium.
The results obtained are as follows:
1. The rate of the callus growth was rapid till about thirty days after the subculture of the callus, then, it became gradually slow.
2. In callus subcultured continuously for over two years, the formation of vessels was observed but the adventitious root was not formed.
3. The callus consists of normal and abnormal cells. Abnormal cells were not normal in size, shape and number of nucleus, and callus growth mainly depends on division of normal cells.
4. The chromosome number in meristematic parts of the callus was abnormal in most cases, but diploid (2n=30) was rarely observed and normal mitosis was observed in it.

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The purpose of this study is to know the mechanism and optimum condition of seed germination for three palms, Chrysalidocarpus lutescens, Mascarena verschaffeltii and Phoenix dactylifera. The seed of Chrysalidocarpus lutescens is global with a slightly pointed edge in the top, while that of Mascarena verschaffeltii is slightly slender oval. These two kinds of seeds are uniform in their tissue of endosperm and they have a tongue-like cotyledon which elongates at a position close to the seed when the germination takes place. The seed form and germination pattern of Phoenix dactylifera are similar to those of Phoenix canariensis, but the seed size of P. daclylifera is a little larger than that of the latter.
The percentage of seed germination in Chrysalidocarpus lutescens was only 30, while those in Mascarna and Phoenix were over 90 at the optimum temperature. The optimum temperature of seed germination seems about 25°C for Chrysalidocarpus. For Mascarena, optimum was 25°C to 35°C, the highest percentage being obtained especially at 35°C. For Phoenix, the optimum range of temperature was similar.
The least number of days from planting to germination was 25, 17 and 15 in Chrysalidocarpus, Mascarena and Phoenix, respectively. The favorable seed bed was vermiculite and sand, sand and clay loam for Chrysalidocarpus and Mascarena, respectively. However, there was no difference among beds examined in Phoenix. The seed of Chrysalidocarpus was so easy to dry that it had lost the germination power two months after harvest. Although the fresh weight of seed of Phoenix reduced about 76% after the storage in room for one year, the seed maintained the germination power at 70%.

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In order to obtain proper indices for edible quality evaluation of commercial Satsuma mandarin (Citrus unshiu Marc.), ordinary parameters of the fruit from major growing areas for three crop years were determined, and statisticaly analysed by means of principal component analysis.
Size and physical parameters do not significantly correlate to chemical parameters, contributing to the edible quality, and are not adequate for the quality index.
Commercial Satsuma mandarin can be classified to several groups on the plane applying principal component analysis. The changes of the quality depending upon growing areas, varieties, harvesting times, etc., are visualized on the plane.
Total sugar content can be accurately estimated from refractive index, using a regression equation. While the estimate of free acid content calculated from pH value gives an approximate index, but is not highly confident.
Total sugar and free acid contents, which respectively contribute to the sweetness and the sourness being chief stimulation of the fruit, give the largest information of the quality among the 17 parameters measured in this experiment. Refractive index and pH value, therefore, suggest to be suitable for the indices in the edible quality evaluation of commercial Satsuma mandarin.

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This investigation was undertaken to examine the effect of packaging with polyethylene bag on incorporation of both 2-¹⁴C-mevalonic acid (MVA) and 2-¹⁴C-acetate into lipids and lycopene by tomato fruits. The results obtained were as follows:
1. Radioactive mevalonic acid was incorporated into nonsaponifiable fraction by tomato fruits which had been injected with 2-¹⁴C-MVA at the stem scar with a hollow needle and syringe.
2. When 2-¹⁴C-acetate was injected into fruit, although the total radioactivity incorporated into nonsaponifiable fraction increased with after-ripening of fruit, it was smaller than that of MVA.
3. In the case of tomato fruits packaged air-tightly in polyethylene bag, the quantity of radioactive substances incorporated into nonsaponifiable fraction was smaller than that in unpackaged fruits, and the incorporation of 2-¹⁴C-MVA went down to 15%, 2-¹⁴C-acetate to 50%.
4. The quantity of 2-¹⁴C-MVA and 2-¹⁴C-acetate incorporated into lycopene by fruit increased with the time elapsed, but it was small when fruits were packaged with polyethylene bag.

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The factorial experiments were carried out to clarify the effects of oxygen concentrations on natsudaidai fruits and to determine the optimum oxygen levels in CA storage. The fruits were stored in nitrogen atmosphere with 0, 1, 1.5, 5, 10, 21% oxygen at 4°C for 2 months and 0, 1, 2, 5, 10, 21% at 20°C for a month in 1968, and in 1969, 0, 3, 5, 7, 10, 21% at 3°C and 20°C, for 2 months and a month, respectively. Carbon dioxide was excluded in all treatments.
1. At 3°and 4°C, no distinct differences were found among O₂ levels in soluble solids and titratable acidity. The decrease of ascorbic acid contents during storage was less at the lower O₂ levels. Before the development of injuries, the critical O₂ levels for the CO₂ evolution rates were not clear. The fermented flavor and the bitter taste were developed below 3% O₂ and the higher ethanol contents were found in the fruits with the fermented flavor. No distinct differences in eating quality were found among 5-21% O₂.
2. At 20°C, the more stem end rot developed, however, the Penicillium sp. development was reduced at the lower O₂ levels. In the titratable acidity, ascorbic acid contents and soluble solids contents, no distinct differences were found among O₂ levels. Below 5% O₂, the fermented flavor and the bitter taste, and high ethanol contents were found.
3. Two types of the injuries were found. (1) At 3°and 4°C, and below 1.5% O₂, the albedo turned watery and yellow, the juice sac turned from orange color to yellow, and in the severe case, CO₂ evolution rate was declined gradually. At 20°C also, the albedo turned yellow at the 0% O₂.
4. Under low O₂ levels in citrus CA storage, three problems, (the decay, the abnormal (fermented) flavor and the puffy fruit with the plumping peel (ukigawa)) must be solved. In natsudaidai fruits, the safety O₂ level in CA storage was 7% at 4°C. The disccusion was made about the abnormal flavor in relation to the peel gas diffusion resistance, internal gas concentration, the anaerobic respiration and the ethanol accumulation.

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1. The present experiments show the identification and the changes of content of lignin, which is considered to be closely related to the hardness of plant tissue in pepper fruits. And the relation to the accumulation of phenolic substances in pepper seeds by low temperature storage reported in previous paper is discussed.
2. The lignin in the peels and seeds of pepper fruits was isolated as lignin aldehydes by the method of alkaline nitrobenzene oxidation described by Stone and Blundell. The quantitative determination of the aldehydes was carried out using paper chromatography.
3. The lignin aldehydes were detected by spraying on paper with 2% 2•4-dinitrophenylhydrazine in 2N HCl. Three spots were found as lignin aldehydes of peels and seeds. One spot was identified as vanillin by the determination of maximum absorption, Rf value, and color reaction of hydrazone while the other spots were unidentified substances.
4. The vanillin content of pepper peels was fairly lower than that of seeds. At 6°C, the vanillin content of peels decreased by half of initial value 2 days after and then increased rapidly during subsequent storage period. The content in 20°C-stored fruits, on the contrary, increased gradually during 2 days of storage. The vanillin content in pepper seeds showed 685μg/g fresh weight before storage, and in the storage at 6°C it decreased rapidly to 417μg/g fresh weight after 2 days, and then increased to reach to a maximum of 807μg/g fresh weight after 7 days and the high level followed constantly during storage periods, while the content of that stored at 20°C increased gradually and reached a maximum after 7 days.

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