The surface of leaves, fruits and twigs from 5-year old Ralls tree grown in minus Ca water culture solution was treated in summer of 1966 either with 0.018M ⁴⁵CaCl₂ or ⁴⁵Ca(OH)₂ solutions to elucidate the distribution of applied ⁴⁵Ca between different parts of the tree.
The results showed that ⁴⁵Ca applied to either upper or lower surface of the leaves penetrated into tissues regardless of the form of salts, and that the distribution of ⁴⁵Ca was greater in younger leaves (leaves on the apex position) than older (basal leaves of the same shoot).
The autoradiographs showed that there was no apparent translocation of ⁴⁵Ca from the treated leaf of mid-shoot position to the adjacent upper or lower leaves. However, slight radioactivity was detected in the fruit when fruit spur leaves were treated with ⁴⁵Ca salts.
⁴⁵Ca applied to the fruit surface by dipping, penetrated to flesh through vascular systems, but radioactivity was greater in skin and core than in flesh.
⁴⁵Ca applied in a cloth tape around 1-year or 3-year twigs was detected 34 or more days in the phloem and xylem under the site of application, and translocated to the extent of 8cm upper and lower directions from the site of application though its radioactivity was rather slight.
Although the ⁴⁵CaCl₂ treatment usually showed greater activity than ⁴⁵Ca(OH)₂, attempts to compare the nature of the two salts were not successful because of the formation of slight precipitation in Ca(OH)₂ solution by addition of wetting agent.
On the basis of these data, it seemed reasonable to assume that the Bordeaux mixture, which contain an excess of lime, may act as a Ca source for the trees, consequently the Ca levels of leaves, branches and fruits increase to some extent by replicated Bordeaux sprays.

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The absorption and translocation of ⁶⁵Zn by Satsuma orange leaves have been investigated. It was found that zinc was readily absorbed by the leaves and addition of calcium hydroxide to zinc solutions resulted in a marked reduction in absorption of zinc. Addition of other elements like boron, molybdenum, magnesium and manganese exhibited a quite irregular trend in inhibition or acceleration of zinc absorption. The absorption in the presence of EDTA was inhibited tremendously, whereas the translocation of absorbed zinc within the tissue was accelerated remarkably. Further, in the presence of a fruit, there was a notable accumulation of translocated zinc in the fruit, proving the formation of strong“sink”to zinc.

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It was found by the authors10) that if citrus trees were cultivated under the alternate high temperature (day: 25-30°C and night: 15-20°C) during winter season, the differentiation of fibrous tissue in wood was taken place even in winter season.
Two year old Hassaku twigs (Citrus hassaku) which had stem pitting on wood were grafted on sweet lime (Citrus limeettioides) stocks. Ten months later, they were used as materials in the experiments. That is, after dividing them into two sets, one set was cultivated under the alternate high temperature (day: 25-30°C and night: 15-20°C) during winter season (from the beginning of October till the end of April) and another in natural condition of the same winter. As a consequence of the experiments, the formation of new stem pitting was not detected under the alternate high temperature (Fig. 3A₁ and A₂), but it appeared on wood in natural conditions (Fig. 3B₁ and B₂).
This observation provided that the stem pitting phenomenon on wood of citrus tree depends on the cambial condition which has been influenced by thermoperiodicity.

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1. The effect of temperature on the fruit growth was studied with Satsuma oranges in each stage of fruit enlargement and maturity, by keeping 3-year-old trees at the various controlled temperatures of the growth chambers (so-called Koitotron). In 1967, 16 experimental plots were made by combining day and night temperature of 15°, 20°, 25°, and 30°C with one another. In 1968, 4 experimental plots by constant temperature of 15°, 20°, 25°, and 30°C were made.
2. The growth of Satsuma orange fruits between 20°and 25°C was consistently superior in diameter (transverse) and weight at the both stages, regardless of day and night temperature. Thus, this fact suggests that no difference of temperature between day and night is necessary for most favorable growth of fruits in the range from 20°to 25°C. However, a higher temperature was generally superior to a lower temperature for the fruit growth in diameter (longitudinal), and the flesh % per fruit was greatest at 25°C.
3. Sugar contents in the fruit juice of around 20°C were always superior at the both stages. However, the content of reducing sugars and their rate in total sugars generally increased with increasing temperature in the range of 15°to 30°C.
4. Titratable acid contents in the fruit juice decreased earlier at 25°C in the stage of fruit enlargement and between 20°and 25°C in maturity. At 30°C or 15°C, however, they did not decrease so easily.
5. Chlorophyll contents in the fruit rind clearly decreased at lower temperatures in the both stages. Paticularly, those contents at 15°and 20°C were much less than at 25°and 30°C.
6. Carotenoids contents in the fruit rind rapidly increased as ripening advanced. As a result, carotenoids contents greatly increased at 20°C over this period. Though carotene contents decreased, xanthophyll contents apparently increased in the stage of fruit maturity. The inverse relationship between xanthophyll and carotene contents was observed especially in lower temperatures. Carotenoids contents in the flesh were mostly consisted of xanthophyll.

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Cabbages are consumed mostly as salads in Japan. The sweetness is considered to be one of their most important factors for the quality. In the preliminary investigation, it was observed that their sweetness was varying with the growing seasons, as well as with the varieties and the places of production. To ascertain the seasonal changes in sweetness, and to find the relation between sweetness and sugar contents, the following studies were carried out.
1. Cabbages of representative varieties in each season were obtained from Tokyo Central Wholesale Market, from June 1964 to May 1965.
Contents of total and reducing sugars in the analyzed samples decreased from June to September, then increased gradually till March, and decreased again until May. But, some cabbages, which were harvested in midwinter, showed low levels in sugar content.
The contents of non-reducing sugars were low during warm season, and were high during cold season. The ratio of reducing sugars/total sugars was over 0.9 in the former, and lower than 0.5 in the latter.
2. On the field of Tokyo University, several cabbage varieties were planted four times from March to October 1966, and were harvested throughout one year since June 1966. The sugar contents of harvested cabbages varied with growing seasons. Their levels were low in warm season, and high in cold season, the same as in the case of above mentioned study. Low sugar contents were found in some wintered-over cabbages, too.
3. Close relationships were existed between sugar contents in cabbages, and degrees of sweetness evaluated by organoleptic tests. The levels of sweetness were in proportion to the sugar contents as a rule, but, there were some exceptions. When the cabbages were suffered from cold injury on the field before harvested time, their taste became rather sweet notwithstanding low sugar levels. Further, if the leaves of cabbages were thick and firm, or containning bitterness, their taste was felt undesirable in spite of their high sugar levels.

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As previously reported, the bulb formation of onion plant was induced by supplementary irradiation with far-red (FR) or blue (B) light but suppressed with red (R) light.
This work was undertaken to clarify the interaction between R and B or FR shown in the bulbing of onion plants under mixed light of R and B or FR.
1.The three- to four-leafed onion plants of“Kaizuka-wase”or“Tyogokuwase-shiro”were daily exposed to the sunlight for eight hours and followed by supplementary irradiation with mixed light of R and FR, of B and FR, and of R and B for sixteen hours.
Coloured fluorescent lamps (Mitsubishi FL-40 F-B and FL-40 F-R) and incandescent lamps were used for blue, red and far-red light, respectively. The sources of light were set 40cm above the plant, and the distance of the plant from source of light was varied from 0cm to 90cm. The radiant energy at plant level was determined by lux-meter and converted one lux into 0.43μw/cm² and 1.12μw/cm² for B and R light, respectively, and for incandescent light through cellophane filters and layer of water, viz., FR light converted one lux (for incandescent light) into 0.154μw/cm².
2. When onion plants were irradiated by mixed light of R and FR light, in general, their bulbing-ratios (diameter of sheath or bulb/diameter of neck) increased with the intensity of FR light, decreased with the intensity of R light, But R light which has lower intensity than FR light in mixed light promoted the bulb formation.
In the case of higher R light, R light was antagonistic to FR light for the bulb formation. On the other hand, in the case of lower R light and higher FR light, R and FR light was synergistic to each other.
Colour of their leaves irradiated with mixed light of R and FR increased with intensity of R light, decreased with intensity of FR light.
These results suggest that no clear correlation is found between colour of leaf and bulb formation.
3. When onion plants were irradiated by mixed light of B and R, the bulbing-ratios increased with intensity of B light, decreased with intensity of R light. In the only case of higher B light and lower R light, bulbing was induced.
The effect of B and R light to the bulbing was antagonistic to each other.
4. When onion plants were irradiated by mixed light of B and FR, the bulbing-ratios increased with intensity of B, and of FR light.
The effect of B and FR light to the bulbing was synergistic to each other.

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Through the analysis of relationship between the change of top-growth and the development of roots during one month from mid-July to mid-August, pot experiments were carried out to make clear the effects of application time of nitrogenous fertilizer on the tuber-formation of sweet potatoes. Two types of soil differing in their clay content, that is, sand and clayey loam were used.
1. The later the application of nitrogen on sandy soil, the greater was the vines elongation from mid-July to mid-August. On the contrary, the sooner the application of nitrogenous fertilizer on clay soil, the more vigorously top-growth during this period was kept.
2. According to the delay of nitrogen application, total number of roots at the stage of mid-July was already smaller on clay soil than on sandy soil, and also the respective number of roots classfied from their diameter was the same. However, no differences was observed among those treatments on sandy soil as to the total number of tuber roots and flat roots next to tuber root, whereas the number of tuber root decreased with the delay of nitrogen.
3. As the results mentioned above, top-growth on sandy soil was kept vigorous during the period from mid-July to mid-August with the delay of nitrogen. The same trend was true on clay soil, too. Therefore, it was comfirmed that regardless of soil it was unfavorable to tuber-formation with the delay of nitrogen, owing to the increase of the distribution of the photosynthesis nutrients for the enhanced vines elongation during this period.

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The growth of Sinningia speciosa plants grown under various light intensities (60, 54, 30, 16, 10, and 5%-daylight) was pursued from March 21 to June 17, 1967.
1. The growth in dry weight of total plant, leaf and tuber were markedly depressed under deep shade (10 and 5%-daylight).
2. The light intensity of 16%-daylight was optimal for the growth in leaf area of main stem. The growth of lateral branches was depressed under deeper shade (16, 10 and 5%-daylight).
3. The ratio of leaf area to leaf weight (L/F ratio) and of leaf length to width (1/b ratio) significantly increased with the decrease of light intensity. Leaves of plants grown under lower light intensities were green in color, while those exposed to higher light were yellowish.
4. Flowering was earlier at higher light condition than at the lower. The size, shape and color of flower were not influenced with shading.
5. Light saturation and compensation points for the apparent photosynthesis were about 10 kilolux and 100-300lux, respectively. The maximal photosynthesis was 4-6.5mg CO₂/dm²/hr. It was somewhat lower in 60 and 5%-daylight leaves as compared with in the middle shaded.

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The possibility to obtain the seeds by the method of test-tube fertilization was examined using a self-incompatible plant, Petunia hybrida, and a self-compatible one, Eschscholtzia californica, as a control.
1. Pollen grains from both tested plants germinated and grew well on the sucrose-borate medium. On the basal medium (Table 1), pollens of E. californica germinated considerably, while those of P. hybrida hardly germinated. Pollen germination and tube growth of the latter were improved, however, in following two methods; (a)“style culture”or (b) culture of whole mass of bare ovules with placental tissue dusted with pollen grains.
2. With E. californica, the ovules developed normally at the early period of the culture, but well developed seeds were not obtained in spite of the subculturing. Some of well swelled ovules formed callus having bud primordia like protuberances.
With. P. hybrida ovules developed well by culturing the whole mass of bare ovules with pollen grains in both cross (fertile) or self (sterile) combinations. Some of the seedlings were obtained by subculturing the developed seeds onto basal medium in the former combination and also in the latter by employing MURASHIGE and SKOOG medium.

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Studies have carried out for the effect of nitrogen nutrient on some flower-bulb crops which are important in the Tottori region.
This paper presents the effect of nitrogen supply and omission at the various stages of growth on the absorption of nutrient, the growth and the yield of Dutch iris by using 5.5±0.2g bulbs of cv.‘Wedg-Wood’in sand culture. Growth period was divided into the following four stages; I, Stage of advance growth (Oct.-Nov.); II, Stage of retardative growth (Dec.-Jan.); III, Stage of later growth (Feb.-Mar.); and IV, Stage of bulb weight increase and maturity (Apr.-mid Jun.). Secondary adventitious roots grew up at the beginning of February. Blooming time was mid-April. Treatments were designed as Fig. 1.
1. Fresh weight, dry weight and dry weight rate of foliage were the highest in nitrogen omission group (C and J) at the end of March when the foliage weight was maximum of the entire growth period of normal plants.
2. Nitrogen supply or omission at stage III dominates the nitrogen level at the end of March when the nitrogen level in the foliage was maximum of the entire growth period of normal plants, in spite of the plants have had nitrogen supply or omission at stage I and II.
3. Nitrogen supply was necessary till the end of stage II for the muximum nitrogen level in the roots at the end of January when nitrogen level of roots was maximum in the entire growth period of normal plants. The nitrogen level of roots increased after stage II if nitrogen supply was not done till stage II but was done at the following stages.
4. Nitrogen omission at stage I and II resulted the decrease of much amount of nitrogen level in the mother bulb. In this case, there was high negative correlation between the nitrogen level and the weight of mother bulb at the end of January. (Correlation coefficient r=-0.979). It was suggested that absorbed nitrogen has close relation with consumption of reserve substance in the mother bulb.
5. Absorbed nitrogen content (Table 12) was little at stage II and paticulary abundant at stage IV. Nitrogen absorption was synergistic with potassium absorption (Table 11).
6. The correlation coefficient of nitrogen concentration among foliage, roots and mother bulb varied largely each other depending upon the stage of growth (Table 4). Its value was especially small between foliage and roots at the end of January (Stage II). It was guessed that absorbed nitrogen content of foliage was so little at stage II that nitrogen removed from top to roots in this stage.
7. The effects of absorbed nitrogen of each stages on the production of the bulbs were shown in Tables 5 and 6, i.e., stage I, non-effective or rather decrease the yield; stage II, the greatest increase in the yield with an ideal quality of either main or lateral bulbs; stage III, decrease the main bulb yield, but tend to increase the lateral bulbs yield. If nitrogen was applied at stage IV, omission in this stage causes maximum yield (J), and stage IV, decrease the main bulb yield, but tend to increase the lateral bulbs yield. (At this period moisture content sensitively increased in connection with the absorbed nitrogen.)
8. The moisture content in the produced bulbs had close relation with the nitrogen concentration (Fig. 5).
9. Relation between the nitrogen concentration in the foliage and the bulbs became higher after stage III (Table 10).
10. From the above investigation it was considered that suitable nitrogen supply for an ideal bulbs production are as follows: 1) Supply it at stages II and III, and omission it at stages I and IV, or 2) supply it at stages I, II and till mid-May of stage IV, and omission it at stage III and after mid-May of stage IV (Table 13).

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The shoots of Cymbidium goeringii (C. virescens) obtained by culturing for 8 weeks in the dark on the basal medium (KNUDSON C with NITSCH microelement) were transferred to the basal medium with both 10mg/l kinetin and 10^-3M L-arginine. After 8 weeks′ culture in the dark, most of samples produced advetitious roots. The shoots cultured on the basal medium with 10mg/l kinetin alone did not produce root.
The shoots being transferred to various kinds of light (white, Vitalux, blue and red) from the dark, most of samples produced adventitious roots at appropriate intensities of light in both C. goeringii and C. insigne.
From these results it may be suggested that the effect of light on the adventitious root formation depends on the intensity rather than the wavelength and is chiefly concerned with photosynthesis and nitrogen assimilation.

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This study was carried out to clarify the effect of low temperature on the bulb or corm formation of the seedlings in the eight kinds of ornamental plants which produce the bulbs or corms in early summer.
The results obtained were summarized as follows:
1. When the seedlings of Allium atropurpureum and A. neapolitanum were maintained at 20°C under long day-length conditions for approximately 140 days, their bulbs were not formed, however, when the seedlings of 4-5-foliage stage were exposed to 5°C for 30 days or 10°C for 50 days, they produced the normal bulbs under 20°C and long day-length.
2. From the results showed in Figs. 1 and 2, it is considered that the requirements of low temperature for the corm formation in Freesia hybrida and bulb formation in A. pulchellum were lower than that in A. atropurpureum and A. neapolitanum. When the germinated seeds of Freesia were exposed to 5°C for 73 days under wet conditions and thereafter they were grown at 20°C, the seedlings produced the corms rapidly.
On the contrary, the requirement of low temperature of A. porrum for the bulb formation was the highest among the tested materials, hence the seedlings of this species became gradually to respond to low temperature as it had grown to a certain size.
3. The seedlings of A. flavum, A. heldreichii and Babiana stricta did not form the bulbs under 20°Cconditions, but their bulbs or corms formation were accelerated after these seedlings were exposed to low temperature.
4. From the results obtained by this investigation, it is considered that the bulb formation in the bulbous plants occurred after they were exposed to low temperature during a certain duration.
Accordingly, it was sure that the bulb formation in the bulbous plants which produce the bulbs or corms in early summer is caused by the seasonal thermoperiodicity as if the flower formation were caused by the vernalization.

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Based on the results of the fundamental experiments in laboratory described in the previous paper, CA plant of semi-practical scale was designed and installed. The pilot equipment is composed of a storeroom, a tower, an aerator, a pump and a pool.
The storeroom is equipped with a unit for the cooling of stored materials and a fun for the circulation of the storage atmosphere, individually. The tower is used for the scrubbing of atmosphere by means of water. The aerator is used for the renewing of water.
With this CA system, there are used a large amount of water than conventional water-scrubber. The storage atmosphere that was scrubbed by means of circulated water was maintenance stably proper O₂ and CO₂ levels. A part of current water that was pumped up was bypassed to the tower and a part of it was bypassed to the aerator.
The atmosphere was circulated between the tower and the storeroom.
At first in operation of the equipment, N₂ gas was introduced into the storeroom to reduce the O₂ content. The respiration rate of the products was reduced as a result. The most part of CO₂ produced by their respiration was removed by water in the tower. The O₂ of their respiration in the storeroom during the storage was supplied from current water in the tower, simultaneously.
Tests on prolonging of the storage lives of the fruits were carried out by using this equipment. It was found that O₂ and CO₂ concentration within atmospheric gases in the storeroom were maintained stably during the storage and the products were kept long and safely.
It is assumed that this closed CA system by means of water and nitrogen is able to be applied to commercial storage.

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1. Holding the fruit at 30 to 40°C for several days lowered the acidity of Citrus natsudaidai. The titratable acid decreased with higher temperatures and number of days treated. However, under these conditions the bitter taste increased and an off-flavor developed.
2. The acidity of sour fruits held at 35°C for 3 days was lowered considerably without impairing fruit quality. This treatment on moderately sour fruits was not so effective.
3. During the treatment respiration of the fruit increased in a climacteric-like curve.
4. The treatment decreased both citric acid and malic acid with the former decreasing the most.

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The fatty acid composition in pulp of tomato to be used for processing was assayed as a step for studying the relationship between lipid in tomato fruits and quality of the products. The cultivars used in the experiment were as follows: Chico, Kurikoma, H-1370, H-1409, VF-36, T-613-1, Nozomi-2, Anahu, Texto-2, and Epoch.
Soluble solid content and pH value were at almost the same level among these cultivars, while pigment content varied markedly. There was no significant difference in pattern of fatty acid composition in tomato pulp among ten cultivars. Linoleic acid was predominant component in both neutral and polar lipid fractions (40-50% and 30-40%). The rates of unsaturated fatty acid to saturated acid in neutral and polar fractions were about 1.9 and 1.7, respectively.

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