Changes in naringin content, the principal bitter component in the juice of Citrus natsudaidai fruit injured by freezing, was determined by high performance liquid chromatography (HPLC) using a Zorbax ODS column and eluting with a water-acetonitrile system. The results were summarized as follows.
1. Flavanone glycosides found in Natsumikan juice were naringenin 7β-rutinoside (narirutin), naringenin 7β-neohesperidoside (naringin) and hesperetin 7β-neohespe ridoside (neohesperidin).
Prunin and/or naringenin, less bitter and non-bitter flavanones produced from naringin by naringinase, were not detected in Natsumikan juice sampless at all.
2. Between the analytical data by Davis method (Xmg%) and HPLC precedure (Ymg%) for quantitative analysis of naringin, there existed the following equation: Y=-2.502+0.647X. Thus, about 65% of the value obtained by Davis method appeared to be due to naringin.
3. In the attached fruit on the tree, Naringin content in the juice obtained from pulp using a hand juice wringer is known to agree well the value of sensory evaluation of bitterness. It increased gradually after freezing below -4.6°C and decreased later. While, in the detached fruit, which were treated at -6.5°C for 11 hours during storage, it increased after the treatment and remained high thereafter.
4. Naringin content per fuit in the attached fruit decreased from 60mg to 45mg, with the advance of granulation caused by freezing.
But in the detached fruit stored at 5°C after freeze treatment at -6.5°C for 11 hours, naringin content per fruit were almost constant, and granulation proceeded more slowly and less severely than the fruit on the tree.

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Ripening changes in chemical composition of the 4 red wine grape cultivars were investigated during 3 years from 1979 to 1981. The cultivars tested were ‘Cabernet Sauvignon’ and ‘Pinot Noir’ belonging to Vitis vinifera, and ‘Muscat Bailey A’ and ‘Cabernet Suntory’ belonging to hybrid (Vitis labrusca×Vitis vinifera), cultivated on the experimental vineyard of Yamanashi University.
The results are summarized as follows;
1. Berry diameter and weight of ‘Cabernet Sauvignon’ reached the maxima of 14.0mm and 1.6g in early October. Those of ‘Pinot Noir’ and ‘Cabernet Suntory’ reached the maxima in early September, being 14.0mm and 1.6g, and 14.5mm and 1.7g, respectively. Those of ‘Muscat Bailey A’ reached the maxima of 20.0mm and 5.0g in mid-September. The berries of ‘Muscat Bailey A’ were larger than those of the other 3 cultivars.
2. At full maturity, the pHs of ‘Pinot Noir’, ‘Cabernet Sauvignon’, ‘Muscat Bailey A’ and ‘Cabernet Suntory’ musts reached the highest values of 3.5, 3.4, 3.4 and 3.3, respectively.
3. In ‘Pinot Noir’, the °Brix reached 17% in early September. In ‘Cabernet Suntory’ and ‘Muscat Bailey A’, the °Brix reached 18% in early October. In ‘Cabernet Sauvignon’, however, the °Brix reached no more than 15% in early October perhaps due to virus infection.
4. The titratable acidity lowered below 1.0g/100ml in ‘Pinot Noir’ in early September, while in ‘Cabernet Suntory’, ‘Cabernet Sauvignon’ and ‘Muscat Bailey A’ it did in early October. All the 4 cultivars were high-acid ones.
5. The time to give full maturity, and the °Brix, titratable acidity (g/100ml) and the °Brix-acid ratio at full maturity were early September, 17.1, 0.96, and 17.8 for ‘Pinot Noir’; late September, 18.0, 0.93, and 19.4 for ‘Cabernet Suntory’; late September, 18.5, 0.92, and 20.1 for ‘Muscat Bailey A’; early October, 15.4, 0.93, and 16.6 for ‘Cabernet Sauvignon’, respectively. The values of the °Brix-acid ratio of the 4 red wine grape cultivars were lower than those of white wine grape ones.
6. At full maturity, the tartaric-malic acid ratios and the glucose-fructose ratios were 1.1 and 1.0 for ‘Cabernet Sauvignon’ and ‘Pinot Noir’, 0.8 and 0.9 for ‘Muscat Bailey A’, and 1.3 and 1.0 for ‘Cabernet Suntory’, respectively. ‘Muscat Bailey A’ was a high-malic acid, and high-fructose cultivar.
7. Several viticultural characteristics of the 4 cultivars were as follows. The 4 cultivars seldom suffered from any disease and were easy to cultivate. ‘Muscat Bailey A’ and ‘Cabernet Suntory’ needed regulation of cropload.
8. The sensory impressions of the aftertastes of the wines made from the grapes of the 4 cultivars were as follows. The ‘Cabernet Sauvignon’ and ‘Pinot Noir’ wines had high qualities with respective aroma, bouquet and taste. The ‘Muscat Bailey A’ and ‘Cabernet Suntory’ wines had fruity aroma, but had a slight labrusca flavor. The occurrence of labrusca flavor seemed to be prevented by harvesting a little earlier. Thus, the harvest time of these two cultivars seemed to be rather difficult to decide.

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Ripening changes in weight and diameter of berries, and °Brix, glucose and fructose content, titratable acidity, tartaric and malic acid content and pH of the grape juice were compared between the virus-free and virus-infected ‘Cabernet Franc’ grape vines.
The results obtained were as follows:
1. The berry weight and diameter and the cluster weight on the virus-free and virus-infected vines reached the maxima in late September, and their values were 2.15g, 14.5mm and 240g and 1.80g, 14.0mm and 170g, respectively, for the virus-free and virus-infected vines.
2. The °Brix of the grape juice of the virus-free vines reached 18% in late September. But that of the virus-infected vines reached 12% in early September, and scarcely increased thereafter.
3. On September 30, the juice of the virus-free vines had 8.43% glucose and 8.96% fructose, but the virus-infected vines had 5.75% glucose and 5.49% fructose.
4. In late September, the titratable acidity of the juice was 0.6g/100ml in the virus-free vines, and 0.9g/100ml in the virus-infected vines.
5. On September 30, the tartaric and malic acid contents of the juice were 0.664 and 0.284g/100ml in the virus-free vines, and 0.900 and 0.388g/100ml in the virus-infected vines.
6. At full maturity, the pH values of the juice of the virus-free and virus-infected vines were 3.30 and 3. 20, respectively.
7. Additionally, red table wines were made from the respective berries and evaluated for their aroma and taste 5 months after brewing. The wine from the virus-free vines had a strong varietal aroma, and had a flat or insipid taste due to low acidity and astringency. On the other hand, the wine from the virus-infected vines had little aroma, and sour and astringent tastes.

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The effect of K fertilization to spinach plants was evaluated by growing them in early summer and autumn with or without K applied as K₂SO₄, 5g each 15l pot. Plant tops were harvested at a marketable stage. Three soils differing in exchangeable K level (249, 322 and 412ppm) were prepared.
1. Mean air temperature and solar radiation were higher and the time to harvest was longer in early summer than in autumn. The dry weight and K content of the top were greater in autumn.
2. K application increased the dry weight significantly in both seasons for the soil with 249ppm K, while it scarcely did so for the soil with 412ppm K. In the soil with 322ppm K, the effect of K application was inconsistent in both seasons.
3. From these results, seasonal variation in effect of K application on the growth of spinach plants was not significant when harvested at a marketable stage.
4. K concentration in the top harvested on the rainy day was high when expressed relative to dry weight, while it was low when expressed relative to the tissue water, as compared with those in the top harvested on cloudy or fine days.

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A high percentage of seed emergence was important for precision seeding using a small amount of the coated seeds. This experiment was carried out to study, using Chinese Cabbage seeds, the effect of mixing fungicides in the coating powder on the control of damping-off which is caused by Rhizoctonia solani Kühn and often obstructs the seed emergence on the field and nursery bed. The results are summarized as follows.
1. Among 8 fungicides tested, iprodione and thiophanate-methyle were most effective when they were mixed in the coating powder at 9 and 10_??_14 percent of the seed weight, respectively.
2. The seed bed and the medium of soil blocks for seeding were inoculated with H-10 and K-1, and then the coated seeds were sown on them. Among 3 fungicides tested, thiophante-methyle was most effective when it was mixed in the coating powder at 10 percent of the seed weight.

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The effects of the combinations of the developmental stage of the flower buds at the start of precooling, the cooling temperature and the initial growth temperature after planting on the flowering and quality of cut flowers were investigated in forced tulip cultivar ‘Trance’.
1. In the bulbs in which the floral organs had been completely developed at the start of precooling, the percentage flowering increased and the quality of the cut flowers became better with a decrease in the cooling temperature. The percentage flowering was higher than 90% for the bulbs which were stored at 2°C or 5°C and then cultivated at the low or medium level of initial growth temperature. However, the blind plants infected with Fuzarium sp. remarkably increased and the quality of cut flowers was deteriorated when the bulbs were storaged at 8°C or the plants were cultivated at the high initial growth temperature.
2. In the bulbs in which no floral organs had been completely developed, the higher the cooling temperature, the greater the elongation of noses, the higher the percentage flowering and the better the quality of cut flowers. However, the percentage flowering remarkably decreased and the quality of cut flowers became inferior when the cooling temperature was low or the initial growth temperature was high.
3. The quality of cut flowers was superior when the bulbs with completely developed flower organs were used for forcing. The flowering time was promoted by higher initial growth temperatures, but the quality of cut flowers was inferior to that of the bulbs grown at lower initial growth temperatures.
4. These results show that for good performance of forced tulips it is necessary to elucidate favourable combinations of the 3 conditions, i.e., the developmental stage of flower bud at the start of precooling, the cooling temperature and the initial growth temperature after planting.

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Four cultivars (‘Arendsoog’, ‘Beatrix’, ‘Continent’ and ‘Super Giant Yellow’) of gerbera were used in this experiment.
The flower stem, also referred to as scape, was used in tissue culture. When the 2nd or 3rd whorl of the disc florets started to unfold, the upper 4cm solid part of the scape just below the head was cut off and sterilized for 2 or 3 seconds in 70% ethanol, followed by soaking in 2% NaOCl for 30 minutes, and then rinsed 3 times with sterilized distilled water. After sterilization, both ends of the scape section were removed 0.5cm in length and discarded. It was divided longitudinally into identical strips. Each strip was placed with the wounded side down on the culture medium composed of MS (Murashige and Skoog, 1962) macroelements at 1/2 strength, Heller′s microelements, Na₂FeEDTA 21.4mg/l, MS organic constituents, 1% sucrose, 6-benzyl amino purine. (BA) 10mg/l and Bacto-agar 0.8%. The pH of all nutrient media was adjusted to 5.6 prior to autoclaving.
The explants were first maintained in complete darkness for 2 weeks, and then subjected to light at intensity of 800lx for 16 hours daily. At the end of 16 weeks, 5 or more shoots were formed per scape.

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The effects of planting depth on the development and growth of contractile root (s) and daughter corm or bulbs were investigated in gladiolus and oxalis.
1. In gladiolus, all contractile roots were markedly depressed in elongation and thickening, being 5mm in length and turning brown at their tips, at a planting depth of 0cm. At planting depths of 15 and 30cm, the contractile roots elongated a little but were very poor in thickening growth. At the standard depth of 5cm, however, they elongated, thickened and then contracted much favorably. In oxalis, the growth of the contractile root was more favored with increases in planting depth within the range 4 to 12cm and even at 0cm it reached about a half of that at 4 to 12cm. They contracted smoothly at all planting depths.
2. In both gladiolus and oxalis, daughter corm or bulbs, like contractile root (s), were always inferior in their growth at a planting depth of 0cm. In oxalis, the daughter bulbs corresponded well in their early growth with the contraction of the contractile root and their final weights were greater with greater planting depths within the range 4 to 12cm. In gladious, the growth of daughter corm was markedly inferior at a planting depth of 30cm, but at 15cm, it was excellent regardless of poor growth of contractile roots and superior, though a little, to that at 5cm, where the growth and contraction of contractile roots proceeded favorably.
3. The contribution rate of the contractile root (s) to the thickening growth of daughter corm or bulbs at the early days of contraction of the contractile root (s) was estimated at about 52% in oxalis regardless of planting depth. While, in gladiolus, it was below 1% except about 18% at a planting depth of 5cm.

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1. ¹⁴CO₂ was fed to the maximum leaf in gladiolus and all the leaves in oxalis at different growth stages. Percentages total export of ¹⁴C 16 hours after feeding were lower at earlier feedings but reached as high as 70% when fed at and after the maximum growth of contractile root(s) in both species. Percentages distribution of ¹⁴C to the contractile root(s) were highest when fed at the thickning stage, instead of the maximal growth stage, of the contractile root(s), that is, at 3- to 4.5-leaf stages in gladiolus and at 4- to 5-leaf stages in oxalis. Their values were 12 and 81%, respectively, and corresponded well with high values of RSS (relative strength as a sink) of the contractile root(s) at the respective stages. Distribution of ¹⁴C to the daughter corm or bulbs was recognized beginning at 3- to 4-leaf stages and its percentage increased in advance of that based on the dry matter in both species. Moreover, in gladiolus, percentages distribution of ¹⁴C to the flower stem increased rapidly at feedings around the maximum growth of contractile roots, but they rapidly declined with flowering. In this case also, the percentages distribution of ¹⁴C increased in advance of those of the dry matter. At least in the mother corm of gladiolus, a percentage distribution of about 10% was found at earlier feedings.
2. The retranslocation of ¹⁴C from the contractile root(s) to the daughter corm or bulbs was investigated after feeding of ¹⁴CO₂ at the growth stages where ¹⁴C was known to accumulate most efficiently in the contractile root(s).
In oxalis, at the early stage of contraction of contractile root when the total loss of ¹⁴C in the contractile root exceeded much over the respiratory loss, an amount of ¹⁴C almost equivalent to the difference between them increased in the daughter bulbs. During the same period, the decrease of ¹⁴C in the leaves was so little that the increase of ¹⁴C in the daughter bulbs seemed to be due to the retranslocation from the contractile root. It also appeared in gladiolus that a part of ¹⁴C-assimilates at 3- to 4.5-leaf stages was retranslocated to the daughter corm via the contractile roots although in less extent than in oxalis, and at the later stages of thickening growth much of ¹⁴C moved into the daughter corm from leaves and via flower stem.
3. Among plant parts, it was only the daughter corm or bulbs in which the amount of ¹⁴C found at the final harvest exceeded that found 24 hours after feeding. Consequently, the increment of ¹⁴C in the daughter corm or bulbs seemed to be due to the retranslocation from some parts other than leaves, and perhaps mainly from the contractile root(s). Then, on the assumption that all the plant parts had the same respiratory rate and so far as the ¹⁴C fed just before the maximum growth of contractile root(s) was concerned, about 70% in oxalis and about 14% in gladiolus of the ¹⁴C found at the final harvest in the daughter corm or bulbs were estimated to be retranslocated from the contractile root(s), while 23% and 65% were from the leaves, respectively. Moreover, the above-mentioned contribution rates based on ¹⁴C corresponded well with those based on the dry matter reported previously.

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This paper was designed to study the seed germination and embryogenesis in Calanthe furcata, Calanthe cardioglossa and Phaius minor. The result may be summarized as follows.
1. The ovaries of C. furcata, C. cardioglossa and Phaius rapidly increased in size and reached their final size 50 to 70 days, 60 days and 40 to 50 days after pollination, respectively.
2. The seeds and embryos of C. furcata, C. cardioglossa and Phaius rapidly increased in size, and reached their final size 70 days after pollination regardless of species.
3. Ovule formation occurred 38 to 40 days after pollination in C. furcata, 34 to 35 days after in C. cardioglossa and 43 to 45 days after in Phaius.
The double fertilization occurred 43 to 45 days after pollination in C. furcata, 39 to 40 days after in C. cardioglossa and 48 to 50 days after in Phaius.
The mature embryo sac was observed to have 5 to 6 nuclei in both C. furcata and C. cardioglossa, and 8 nuclei in Phaius.
After pollination, 85 to 90 days in C. furcata, 75 to 80 days in C. cardioglossa and 95 to 100 days in Phaius were required for the completion of embryo development.
4. Proembryos of C. furcata, C. cardioglossa and Phaius at the tetrad stage were allclassified to the A₂ type, according to Veyret's classification. Similarly, embryos of C. furcata, C. cardioglossa and Phaius at and after the tetrad stage seemed to belong to the E type (Liparis pulverlenta type).
The mature embryo was observed to be derived from the apical cells of proembryo in C. furcata, C. cardioglossa and Phaius.
5. Three to 5 endosperm nuclei were observed in the embryo sac after fertilization in C. furcata, C. cardioglossa and Phaius.
6. The seed of C. furcata, C. cardioglossa and Phaius had an ability to germinate at the octant stage (60 days after pollination).
The highest percentage of seed germination was obtained when the seeds were harvested near the mature embryo stage. As the germination medium, the Hyponex medium was better than the Murashige and Skoog, and Knudson C media.

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The respiration, ethylene production and ripening of Japanese persimmon fruit (Diospiros kaki Thumb. cv. Fuyu) harvested at different stages of development were determined individually at 25°C. Stage I fruit harvested in June and July exhibited climacteric-like increases in respiration and ethylene production, softened and yellowed. The calyx of every fruit in stage I abscised at the peak of ethylene production. There was a close parallelism between respiration and ethylene production.
Stage II fruit harvested in August exhibited an increase in respiration without peak, produced ethylene with clear cut peak, softened and yellowed. The calyx of fruit did not abscise.
Stage III fruit exhibited an increase in respiration, produced a small quantity of ethylene and softened. There was no peak both in respiration and ethylene production. The calyx of fruit did not abscise.
It seemed that the ability of ethylene production in fruit decreased rapidly as the fruit matured.
The rates of respiration and ethylene production varied considerably with individual fruits, and it appeared better to determined them individually.
In view of its characteristics mentioned above, Japanese persimon fruit (cv. Fuyu) was considered to be a type of fruit which differed from both climacteric and nonclimacteric fruit.

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Japanese apricot (mume) fruits are usually harvested at mature green stage in June and used for liquor production or processed as umeboshi (a kind of pickles). However, they begin yellowing and softening in a short time and lose their salability. Thus, the shelf life is only 2 or 3 days at 22°C, which is average temperature in June. This study was done to investigate the effects of seal-packaging and removal of ethylene originated from fruits on extending the shelf life at 22°C.
1. Respiration of the fruits held at 22°C revealed climacteric pattern, and a large quantity of ethylene was evolved during climacteric rise.
2. Ethylene treatment of the fruits advanced the onset of climacteric rise and post-harvest ripening.
3. Seal-packaging of fruits with polyethylene (PE) bags, which reduced oxygen level in the bags to 1 to 4%, and ethylene removal in the sealed atmosphere by ethylene removing agent extended the shelf life by 2 and 4 days compared with unpackaging, respectively.
4. Oxygen level below 0.5% in the sealed bags caused visible injury or metabolic abnormality in the fruits.

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For clarifying the process of chilling injury in cucumber fruit, organelles were isolated by means of sucrose density gradient centrifugation, and the profiles of distribution of activities of marker enzymes, especially in mitochondria, on the sucrose density gradient were analyzed. The fruit packed with perforated polyethylene bag was stored at 1°C and 15°C. Pitting on the surface of the fruit, a visible symptom of chilling injury, was observed after 5 days of storage at 1°C, whereas in the fruit stored at 15°C, sound appearances were kept for more than 7 days. The fruit stored at 1°C for 3 days was healthy, and even after transferred to 15°C no pitting injury developed. The rate of K⁺ ion leakage into desalted water from the section prepared from the fruit stored at 1°C increased linearly as storage time increased, indicating that an increase of membrane permeability may occur preceding the development of pitting.
The activities of cytochrome c oxidase located in inner membrane of mitochondria and malate dehydrogenase located in matrix decreased before the development of pitting. This suggests that the lowering of the function of mitochondria took place at low temperature before the occurrence of visible symptom of injury. When the fruit was transferred to 15°C at early stage of low temperature storage (3 days at 1°C), a recovery of the enzyme activities was recognized.
The activity of NADH cytochrome c reductase located in outer membrane of mitochondria increased soon during the storage at 1°C, and broadening of distribution of this enzyme on sucrose density gradient was observed with the fruit which exhibited pitting injury, while the activity of the enzyme taken from the fruit stored at 15°C decreased during the storage.

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