A wide range of variation was revealed among 13 grape cultivars in terms of means of osmotic potential of berry juice, berry size, and cracking index. Cracking density and percentage of cracked fruit were determined by dipping berries in a nonionic surfactant water solution for 10 hours. Analysis of the distribution of skin stress by a computerdigitizer system indicated that the distribution of the cracking density and fracture pattern were affected by the distribution of the factors of stress concentration in the direction of the longitudinal (FSC_L) and latitudinal arc (FSC_H) for most of the cultivars.However, in some cultivars these indices were independent of the distribution of stress concentration and berry cracking seemed to occur. because of the fragility of limited area of skin. Distribution of the FSC_L and FSC_H values was markedly influenced by the berry shape. Both values were uniformly distributed when the berry shape approached a sphere. However, FSC_H values were larger than FSC_L values and the range of fluctuations of the FSC_H values became wider with an elliptically shaped berry, particularly in 'Rizamat' which was found to be the most suscpetible to berry cracking. 'Rizamat' berries had a high density of ring fractures in the stalk cavity with a concomitant increase of FSC_L values in this region. The susceptibility to berry cracking did not correlate with the osmotic potential of berry juice or the berry size, but showed a significant positive correlation with the ranges of FSC_H values. Therefore, the uneven distribution of skin stress seemed to play a role in the susceptibility of grape berry to cracking.

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Five-yr-old Ishizuchi. chestnut were exposed to Relative Light Intensity (RLI) of 100, 50 and 20% late in the season to study the effects of differential shading on dry matter partitioning among the different tissues and amyloplast development in the cotyledons.
Dry matter accumulated in the cotyledon more rapidly under RLI 100% than it did under RLI 50 or 20%. The dry weight of the cotyledons at harvest under RLI 20% was less than a quarter and the dry matter partitioning ratio was about half of that at RLI 100%.
The endosperm tissue which developed after fertilization was absorbed by the enlarging cotyledons. As RLI was reduced, the absorption of the endosperm was delayed. In cotyledonary parenchyma cells, the aperture-like vacuole enlarged with reduced RLI and the rate of accumulation of amyloplast was slow.
These findings suggest that when tree crown are exposed to low solar radiation late in the growing period, not only is fruit yield reduced, but embryo quality and flavor are also diminished.

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Physico chemical characteristics of segment membranes were studied in 'Miyagawa Wase' and 'Hayashi Unshu' as related to delayed harvest. In this study, we focused on segment membrane strength because it may be a critical factor in evaluating fruit quality.
1. Large fruits had thicker segment membranes than did small fruits in both cultivars. Segment membranes of developing fruits, while yet immature, became thinner in 'Miyagawa Wase' but thicker in 'Hayashi Unshu'. The membrane became thinner, however, in 'Hayashi Unshu' as the fruits matured.
2. Intrusive resistance as an index of segment membrane strength was higher in larger fruits. With the advancement of maturation, it became lower in 'Miyagawa Wase', whereas it showed little or no changes in 'Hayashi Unshu'.
3. Some morphological differences in cells of the segment membrane between the two cultivars were observed in late February. The inner epidermal surface of the segment membrane showed some cracking in 'Miyagawa Wase'. Cell size of the outer epidermis of the segment membrane was larger in 'Hayashi Unshu' than in 'Miyagawa Wase'. Some digestion of the cell membrane was found in the latter.
4. Cellulase and polygalacturonase activity in segment membrane increased more rapidly in 'Miyagawa Wase' than it did in 'Hayashi Unshu' after November as the fruit ma- tured. Contents of cellulose and total pectic substances in the segment membrane per 100 g whole fruit fresh weight decreased rapidly after December. This tendency was more pronounced in the smaller fruits of 'Miyagawa Wase'. Cellulose content on a dry weight basis of alcohol insoluble solids (AIS), in segment membrane, was lowest in the smaller fruits of 'Miyagawa Wase'.
We believe that changes in segment membrane strength are caused, not only by digestion of the segment membrane through degradation of cellulose and total pectic substances, but also by qualitative changes of the membrane itself through the decrease of cellulose content as determined by AIS.

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Pollen tube growth in female flowers of Japanese chestnut (Castanea crenata Sieb. et Zucc.) 'Yamato-Wase' was investigated to clarify the relation between fertilization and degeneration of ovules.
1. Pollen tubes were first observed at the uppermost part of the style on 2 July and 2 to 6 July in the central and lateral female flowers, respectively.
2. Penetration of pollen tubes into ovaries occurred on 14 and 16 July in the central and lateral female flowers, respectively. The longest pollen tube growing in an ovary covered the average distance from the distal end of ovary to the nucelli of ovules by 28 July and 1 August in the central and lateral female flowers, respectively.
3. The first pollen tubes penetrated the ovarian locules on 24 and 28 July in the central and lateral female flowers, respectively. Four to five tubes per ovary were observed from 28 July to 3 August in the former and from 30 July to 3 August in the latter. The number of pollen tubes, however, decreased by August 5.
4. Pollen tubes reached nucelli in 26 and 30 days after pollen germination on stigmas in the central and lateral female flowers, respectively. The average distance from the stigmas to the nucelli at this stage was 8 mm in the former and 9 mm in the latter. Thus, their average elongation rate was calculated to be 0.3 mm a day.
5. Nucelli of most ovules in each ovary developed between 12 and 19 July. Ovules except the largest one in an ovary nearly ceased to enlarge after 26 July. After 2 August, ovules with a degenerated nucellus in ovaries were observed. Their ratio increased to 40% on 6 August and reached nearly 100% on 9 August. But one well-developed ovule with an embryo of 0.037 mm in diameter was observed in each ovary on 9 August. The ovule with such an embryo grew rapidly after 13 August.
6. Nucelli began to degenerate within a week after fertilization time in most ovules, suggesting that the degeneration might be caused by the lack of fertilization.

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Crown gall tumors were obtained from three cultivars, 'Fuyu', 'Jiro', and 'Nishimurawase', of Japanese persimmon incited with A. rhizogenes wild type strain A4 harboring agropine type Ri plasmid (pRiA4b). When the tumors were cultured on MS (1/2N) medium containing 10 μM zeatin, 10 μM IAA, and 500 mg•l^-1 cefotaxime, calli were induced from the tumors. After the establishment of axenic cultures, more than 60% of the tumor-derived calli formed adventitious buds on MS medium containing 10 μM zeatin and 0.1 μM IAA. These buds could be developed into shoots on MS medium supplemented with 5 μM zeatin and 1 μM IBA. PCR and Southern blot analyses revealed that some of the regenerants from tumor-derived calli were Ri TL-DNA transformants but that non-transformants were regenerated also from the tumor-derived calli. Phenotypic alterations such as dwarfness and decrease in rooting ability were observed in the transformants.

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The relation between cell division in the root tips and soil temperature was investigated by comparing Japanese persimmon trees cultured in a plastic house with those grown and outdoors. The air temperature in a plastic house was kept at or over 19 °C from 19 March to 2 June. At every sampling date the 40 root tips from five to ten 23-year-old trees were collected at a distance of 1 m around the trunk and from 10 to 40 cm depth. The tips were dipped in 0.002 M 8-hydroxyquinolin (5°C) for three hours and then fixed in acetic acid-alcohol for microscopy.
1. The root tips from trees growing in a plastic house or outdoors exhibited cell division on 22 March. The mitotic index of the roots cultivated in a plastic house increased from 22 March to 2 June when it reached maximum; the high level was sustained until 18 July. It decreased gradually after August; no cell division figure was observed in root tips sampled in 2 October. The mitotic index of roots cultivated outdoors increased gradually until 2 August and then decreased; no mitotic figure was observed in samples collected on 17 September.
2. A significant positive correlation existed between the mitotic index of the roots and soil temperatures between March and July. Extrapolating from the relationship, the temperature which induces cell division was 11.7°C.
3. The cell division-temperature relationship obtained from August to October indicated that the soil temperature, when the mitotic index decreased, was 21°C.
4. Whether the root tips were sampled from trees cultivated indoors or outdoors, they could be white or black. About 40 percent of the root tips sampled between 2 May and August from indoor trees was white; the same frequency of white roots on outdoor trees was observed between 2 June and August. No white root tips were observed after September.
5. The mean mitotic index of black root tips was about 0.1%, whereas that of white one was about 0.4%.
6. The proportion of white root tips increased as the soil temperature exceeded 19°C.
7. The appearance of white root tips had relation with the end of shoot growth or anthesis.

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Abnormal swelling of the rachis of 'Muscat of Alexandria' grapevines grown in a heated glasshouse was investigated. The swelling became apparent at the peduncular node or along the rachis three to four weeks after full bloom. Berry growth was inhibited thereafter with the degree of inhibition varying among clusters. Anatomical studies revealed that a mass of small parenchyma cells divided among or around the phloem tissue two to four weeks after anthesis, which stymied further development of sieve tubes. Numerous granules (0.52.0 μm in diam.) were observed in these meristematic cells under SEM.

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The yields and fruit quality of 'Fuji' apple trees on 'Marubakaido' rootstock with the M. 26 interstock trained to a Y-trellis system were compared with those trained to a central leader. The experiment continued until the trees were 9-yr-old.
1. The trees in the Y-trellis system consistently yielded more fruits annually than did those trained to a central leader, the former yielded 6.200a, 1.3 times more than did the latter in the final season.
2. No significant difference in fruit weight was observed between two training systems, but the fruit color was superior and soluble solids content (brix) was higher in fruits harvested from the Y-trellis system than they were in fruits from the central leader trees. 3. The crown density of 8- to 9-yr-old trees trained to the Y-trellis reached 96%, whereas that of central leader trees attained only 75% ; the maximum leaf area indices (LAI/land area) were almost the same, about 3 in both training systems, and the maximum LAI/tree crown area were 3.8 and 3.2 respectively.
4. Maximum yields were attained when the crown density attained the ultimate levels in both training systems, and reached to each maximum level at the LAI of 3 in the Y-trellis and at that of 2.3 in the central leader.
5. From above results, it seems possible to assume that the superior yield and fruit quality obtained in Y-trellis is due to its higher crown density as well as its larger LAI.

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To elucidate the mechanism of flower differentiation, a study was conducted on the morphological and cytological changes in apical meristem of Japanese pear (Pyrus pyrifolia Nakai cv. Shinsui) during flower differentiation comparing buds on spurs and vegetative buds on elongating shoots. Emphasis is put on the stages until sepal differentiation.
1. First sign of morphological flower differentiation became evident on June 26. The bud scales loosened and the apical meristem began to enlarge. Primordia of lateral flower buds appeared on July 3. In apical meristem sepal primordia differentiated on July 10, followed by the petal primordia on July 17, and stamen primordia on July 30. The pistil primordia appeared between September 2030.
2. Apical meristem was divided into the following 4 zones by the arrangement, shape, and cytology of the cells: tunica, corpus, quiescent zone and pith. Tunica and corpus were the main dividing tissues in which the cells contained small vacuoles and few starch grains, whereas cells of quiescent zone and pith contained larger vacuoles and many starch grains.
3. When the apical meristem began to enlarge, an indication of flower differentiation, the following was observed: 1) starch grains started to accumulate in the cells of quiescent zone, 2) the activity of corpus cells was enhanced, 3) shape of the cells of corpus and quiescent zone changed, and 4) the number of tunica cell layers decreased while the number of corpus cell layers increased.
4. The cells in queiscent zone and pith of apical meristem of the buds on spurs contained a large amount of starch grains which markedly increased particularly in the cells of quiescent zone during the enlargement of apical meristem. Contrarily, no accumulation of starch grains was observed in the cells of vegetative buds on the elongating shoots. In the apical meristem of the flower buds, starch grain temporarily appeared in the corpus cells but soon disappeared. After the sepal differentiation began, starch grains nearly disappeared in all parts of the apical meristem.
5. Role of quiescent zone in flower differentiation is discussed in relation to starch metabolism in these cells.

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To elucidate the mechanism of flower differentiation, ultrastructural changes, particularly the changes in amount and shape of organelles were investigated in the apical meristem of the buds of Japanese pear (Pyrus pyrifolia Nakai cv. Shinsui) during flower bud differentiation.
1. The most important stages in the flower bud differentiation were from the beginning of activation of corpus cells on June 26 to the differentiation of sepal primordia on July 17. During these periods all the organelles in the cell underwent remarkable changes.
2. During flower differentiation the number of dictiosomes markedly increased with concomitant cytomorphological changes such as many larger vesicles and the reduction in length of dictiosome itself. Distribution of endoplasmic reticulum (ER) also increased with the increase in ribosome. ER evolved into a kind of network from a discontinuous linear shape. There also existed active dictiosomes associated with ER.
3. The number and size of mitochondria increased during flower differentiation. As the size increased the shape became spherical or oval. The number and size of plastids in the cells of active tissues did not differ between flower buds and vegetative buds. The size of plastids in the cells of quiescent zone changed markedly, increasing initially and then decreasing, because the size was closely related to the amount of starch grains the plastids contained.
4. While flower differentiation progressed, chromatin in the nucleus increased and became densely stained in the cells of apical meristem of the flower buds. Nucleoli also increased in size, and occasionally two nucleoli were observed in a nucleus. Actively dividing cells in the apical meristem of flower buds were also characterized by many small vacuoles.
5. These ultrastructural changes of the organelles in the cell of flower buds were discussed in relation to their physiological roles.

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Various parts of developing Valencia orange fruits were analyzed for abscisic acid (ABA) and indole-3-acetic acid (IAA) by gas chromatography-electron capture detector and -mass spectrometry-selective ion monitoring with ³H-ABA and [¹³C₆] IAA as internal standards. The flesh and seed weight increased rapidly, while the albedo and flavedo weight increased gradually. The seed had a large peak of ABA concentrations (21 nmol•g^-1 fresh weight) 150 days after full bloom (DAB), while the flesh had a small peak (5 nmol•g^-1 fresh weight). IAA concentration in the seed decreased till 150 DAB but remained higher than other parts. In the central vasuclar axis, the IAA concentration reached a peak on 119 DAB. The level remained higher than those of the flesh, albedo and flavedo. The albedo and falvedo had an equally low level of IAA. We speculate from the analyses of the different fruit parts that 1) the ABA in the seed and IAA in the central vascular axis play a role in the accumulation of assimilates; and 2) the difference in ABA concentrations between the pulp and the peel indicates that no cross transfer occurs between these two tissues.

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June-bearing strawberry plants (Fragaria X ananassa, cv. Toyonoka) were grown at 22°/20°C (day/night) under at 10.5-hr daylength for 18 days in order to induce flower buds, and then transferred to a growth chamber maintained at 22°/20°C (day/night) under either a 15-hr (LD) or a 10.5-hr (SD) daylength.
Plants under LD bloomed earlier than did those under SD because the primary clusters of the LD plants emerged earlier than did those of SD plants. The number of days between emergence of the trusses and anthesis was not significantly different under SD or LD. When the primary flowers blossomed, the peduncles subtending them were longer on plants under LD than they were under SD. This difference in peduncle length is attributed to the greater number of epidermal cells which indicate that cell division is prolonged under LD conditions. Insofar as flower buds were initiated under initial SD conditions, early truss emergence resulted in early anthesis.

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Experiments were conducted to assess the importance of the length and the number of epidermal cells in regard to runner length in June-bearing strawberry plants (Fragaria × ananassa, cv. Donner).
When the elongation rate of proximal internode (I-1) reached the highest rate, the distal internode (I-2) started to elongate exponentially. The elongation pattern of each internode was represented by a single sigmoid curve. The cell division in I-2 continued for about 5 days longer than that in I-1.
I-1 and I-2 under a 16-hr day (LD) grew longer than did those which grew under a 9-hr day (SD). The increase in the internode length of I-1 was attributed to the increase in the epidermal cell length, whereas, the increase in the internode length of I-2 was attributed to the increase in the number of epidermal cells. The differences between I-1 and I-2 of strawberry runners in photoperiodic response to the length and number of epidermal cells may be attributed to the difference of developmental stages in each internode at the onset of the photoperiodic treatments.
In photoperiodic response to the length and number of epidermal cells, there was a similarity between runners and petioles.

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Unfilled grains (caryopses) at the tip of 'Honey Bantam 36' sweet corn ear are classified as unfertilized grains (UG) and fertilized but poorly ripened ones (PRG) according to their morphological characteristics. The anomaly was induced by: a) bagging the ear (female inflorescence) before or after the appearance of the silk (filamentous style and stigma) to obtain UG and b) cutting of leaf blade to obtain PRG. Untreated control corn stalks were kept to obtain normal, filled grains (FG). The effect of different plant densities and cultivars on occurrence of UG and PRG were also investigated.
1. An ear of corn usually consists of FG, UG, and PRG. The filled and unfilled grains are easily distinguished by the length of the ovules.
2. The UG and PRG at the tip of an ear are differentiated anatomically because in the PRG, remnants of an embryo and the endosperm would be present. In addition, the PRG would exhibit browning at the chalazae, partially developed glume, palea, and lemma, and an intact silk.
3. Fertilized grains can be differentiated from unfertilized ones 16 days after silk emergence by their size, whereas the difference between UG and PRG are detectable 20 days after silk emergence by their external and internal characteristics.
4. The occurrence of UG and PRG varied among cultivars and was affected by plant densities; the higher plant densities favored the formation of PRG to lack of photosyn- thates.

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To determine the causes of the development of the unfilled grains consisting of unfertilized and poorly ripened grains at the tip of an ear of sweet corn (cv. Honey Bantam 36), the relationships between (i) pollen shedding time and pollen viability, (ii) silk (style) elongation and pollination/fertilization time of florets, and (iii) the fertility of florets and filling ability of caryopses were investigated.
1. Pollen shedding from tassel florets lasted from 2 days before to 6 days after the first silk appearance (FSA). The germination ratio of the shedded pollen decreased significantly 6 days after FSA. 2. Silk emergence from florets proceeded acropetally; silk from the 30 th to 40 th tip florets from the base of the ear emerged 4 to 6 days after FSA. These silks were pollinated and the egg in the ovary fertilized between 6 to 8 days after FSA.
3. Bagging an ear to prevent open-pollination resulted in mostly unfertilized grains; whereas, comparable hand-pollination developed into normal, filled grains. Consequently, florets at the ear tip were receptive and capable of developing into normal grains as late as 10 days after FSA.
4. Hand-pollination florets, 6 days after FSA under natural conditions (without bagging), resulted in partially filled grains.
We attribute the presence of unfertilized grains at the corn ear tip to lack of viable pollen for pollination and the development of the poorly ripened grains to an insufficient supply of current photosynthates.

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The effects of NO₃ : NH₄ mixture with a gram-N ratios of 10 : 0, 9 : 1 and 8 : 2 in the nutrient solution and shading pepper plants grown under NFT to 0, 25 and 50% full so- lar radiation on their growth, yield, and photosynthesis were investigated.
Main stem and branch lengths increased significantly under shaded conditions. Fresh weight of leaf, stem, and roots of equally shaded plants were heavier at a NO₃ : NH₄ ratio of 9 : 1 compared to those grown at a ratio of 10 : 0.
The pepper plants set fewer, smaller fruits in proportion to the degree of shading. Fruit yieid of the shaded plants increased significantly by replacing 10% of NO₃-N with NH₄-N in the nutrient solution.
Dry weights of leaf and stem and leaf area increased under shaded conditions. As the NH₄-N/NO₃-N ratio in the nutrient solution increased, dry weight and leaf area decreased in fully exposed plants, whereas the trend was reversed in shaded plants.
As the NH₄-N/NO₃-N ratio of the nutrient solution increased, leaf photosynthetic rates decreased in exposed plants, but increased slightly in shaded plants.
Compared with exposed plants, shaded plants had considerably lower net assimilation rate (NAR) and relative growth rate (RGR) during the flowering and the early fruit development stage, 46 days after treatments, irrespective of the nitrogen sources in the nutrient solution. However, the differenes were observed in NAR and RGR during the later fruit maturing stage, 47 to 68 days after treatments.
The results obtained in this study indicate that as a nitrogen source of NFT-grown pepper plants, 100% NO₃-N is recommended under high solar radiation, whereas a NO₃-N : NH₄-N ratios of 9 : 1 or 8 : 2 is superior when the solar radiation is reduced.

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In F1 hybrid seed production, the elimination of contaminated self and/or sib-crossed seeds from hybrid seeds is an important subject. We attempted to use RFLP analysis of nuclear DNA for checking the seed purity of the F1 hybrid cucumber. Between the two parental lines which are promising for an F1 cucumber cultivar, two RFLP clones were established. The frequency of RFLP clones in the genomic library was 1%. Two micrograms of DNA, which could be isolated from a 9-day-old seedling, were sufficient for RFLP detection with non-radioactive Southern hybridization. This system enabled a practical and a rapid check of the seed purity in an F1 hybrid cucumber.

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The initiation of floral organs, especially that of petal primordia was observed by a scanning electron microscope in cabbage, Chinese kale, kohlrabi, kale, hong-tsai-tai, pakchoi, tsai-shin and Japanese radish.
1. Seven floral stages could be discerned in cultivars in every species the vegetative stage; the dome-forming stage; the flower bud-forming stage; the sepal-forming stage; the stamen and pistil-forming stage; the early petal-elongation stage, and late petal-elongation stage.
2. Petals and outer stamens of tsai-shin were formed earlier followed by the initiation of inner stamens. In other cultivars, the petals and stamens were initiated almost simultaneously.
3. Petal primordia were smaller than those of other floral primordia and their development stopped soon after initiation. The elongation of petal was delayed, compared with that of stamens and pistil.
4. These observations confirm the normal seqence of sepal initiation followed by those of petals, stamens, and pistil in all eight cruciferous vegetables studied.

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Exogenous ABA application was evaluated as a countermeasure for high-temperature stress injury in cucumber (Cucumis sativus L.). Seedlings were sprayed with 0, 0.01, 0.1 or 1mM ABA and then treated at 29°C (normal temperature) and 41°C (high temperature) for 3 hr. Leaf temperature, transpiration rate and chlorophyll fluorescence emission of ABA-treated and untreated leaves were determined during the temperature treatment.In addition, the residual effects of ABA and high-temperature treatments on stem elongation rate and the early fruit yield were assessed after the plants were transplanted into the field. Emission of chlorophyll fluorescence from the leaves was inhibited by high temperature and the inhibition was greatly amplified when the leaf was sprayed with 1mM ABA before the high-temperature treatment. ABA treatment provoked a rise of leaf temperature in proportion to its concentration in both temperature treatments and at 1mM ABA the leaf temperature attained 45°C during the high-temperature treatment. This marked rise of leaf temperature was probably due to a great inhibition of transpiration. In the same condition of vapor pressure deficit, transpiration rate was not affected by the high-temperature treatment without ABA, but declined with increasing ABA concentrations. The decrease was particularly great at 1mM ABA under the high-temperature condition. Subsequently, necrosis, chlorosis, cupping of leaves and depression of stem elongation occured on the plants treated with 1mM ABA and high temperature. In the field experiment, early fruit yield was lower, although insignificiantly, only when the plants had been treated with both 1mM ABA and high temperature. It is concluded that leaf temperature critical to injury in cucumber is about 45°C and ABA is injurious to plant growth under high-temperature stress, i. e., ABA at high concentrations promotes hightemperature injury of cucumber leaves by rising leaf temperature above the critical temperature through decreasing transpiration. Chemical name used: abscisic acid (ABA).

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Cucumber plants (Cucumis sativus L. cv. Sharp I) with 3 leaves were grown in hydroponics at root temperatures of 25°, 32°, 35° and 38°C for up to 9 days. The rates of photosynthesis and transpiration as well as leaf chlorophyll content was not affected by the root temperatures from 25° to 35°C. In plants grown at 38°C the rates of photosynthesis and transpiration were unaffected over the first 5 days, but a large decrease occurred in the two parameters as well as chlorophyll content after 9 days. When a shoot was pulse-fed with ¹⁴CO₂ after 6 days growth at 25° or 38°C root temperatures, translocation of ¹⁴C-photosynthates to the roots during a 10-h chase in darkness was faster at 38°C than it was at 25°C. However, the amounts of the ¹⁴C accumulated per unit dry weight of root tissue were not different between the two treatments, becuase of an increased carbon loss by respiration of the roots at 38°C. At 38°C, more ¹⁴C was allocated to soluble C than to insoluble C; the reverse was the case at 25°C. Fractionation of soluble ¹⁴C into sugars, organic acids, and amino acids revealed that in the roots at 38°C, a very large proportion of ¹⁴C was in the sugar fraction, particularly raffinose. This was in contrast to the 25°C roots in which the soluble ¹⁴C was distributed evenly to the three fractions. Possible relationships of the changes in photosynthesis and photosynthate translocation and metabolism in the roots with root growth and functions under the high root temperature conditions are discussed

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As reported earlier, the authors have discovered in Kagoshima Prefecture, Japan, two new types of Lycoris which have straw-coloured (L. sp. A) or vermilion (L. sp. B) flowers. Their morphological characters, presence of pelargonidin in the perianth, low pollen fertility, and characteristic karyotype (5 V +12 R in L. sp. A and 4 V +14 R in L. sp. B) suggested that these new types of Lycoris may be hybrid between L. traubii and L. sanguinea. In this paper, inter-specific their hybridization between these two species was conducted and 32 offsprings analyzed to confirm the our hypothesis.
1. The percentages of capsule set in L. traubii X L. sanguinea and its reciprocal crossing were 7.3 and 30.1, respectively. The morphological characters of these offsprings were intermediate between both species and the several leaf characteristics such as time of emergence, glossiness, shape of apex and length/width ratio resemble L. sp. A and B. 2. Even though a few individuals with partly deleted chromosome and an aneuploid were obtained, the chromosome numbers of somatic cell in these hybrid offsprings were either 17 or 18, and their karyotypes of 5 V +12 R or 4 V +14 R chromosome configuration also coincided with either L. sp. A or L. sp. B.
The idea that inter-specific hybridization occurred in the past was difficult to reconcile because the two species flower about 1.5 to 2 months apart. However, an extensive survey on the distribution of Lycoris species revealed the presence of an autumnal flowering L. sanguinea in central and southern Kyushu, and especially in Narikawa area in the town of Yamagawa where L. sp. A and B were found in abundance. Lycoris traubii and L. sanguinea were growing side by side and flowering simultaneously from mid- to late September.
Based on their distribution, morphological characteristics, and chemical and karyotypic similarities, we conclude that L. sp. A and B are inter-specific hybrids between L. traubii and the autumnal flowering form of L. sanguinea and that their origin would be the southern part of the Satsuma peninsula, or more precisely, the Narikawa area in the town of Yamagawa in Kagoshima Prefecture.

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Embryogenic callus (EC) was initiated from inner tissue (IT) of protocorm-like bodies (PLB) of Cymbidium orchid cultured on Murashige and Skoog (MS) media supplemented with 1-naphthaleneacetic acid (NAA) or 2, 4-dichlorophenoxyacetic acid (2, 4-D). EC was obtained within 15 days on a MS medium containing 2 mg•liter^-1 NAA or 0.5 mg•liter^-1 2, 4-D which was the most effective among the concentrations tested. When EC were transferred to a hormone-free MS medium, they produced protocorms within one month and complete plants in another 3 months. In contrast, the EC, in the presence of BA or NAA, produced light green, hairless, string-like structures in one month. These string-like structures grew 2 to 3 cm in length and died within three months. IT produced no callus in hormone-free MS medium or in a medium to which BA and NAA were added. After 5 days of culture, with NAA or 2, 4-D, a small mass of EC differentiated from the parenchyma cells of the vascular bundle on the basal cut end of IT sections. These ECs produced proembryoid-like structures after 10 days of culture; they became globular embryos 5 days later. The globular embryos differentiated into protocorms and plantlets after being transplanted to the hormone-free MS medium. These findings demonstrate that Cymbidium plantlets can be obtained from IT of PLB through somatic embryogenesis by manipulating the culture conditions.

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White callus induced from mother scale of Lilium japonicum Thunb. was cultured on MS-medium without plant hormones under continuous 2000 lx at 25 °C in vitro. A bulblet regenerated on the white callus was used for treatments.
1. Small bulblets, 15 to 18 mg (FW), were imbedded on MS-media containing of NAA (0.2, 1.0 and 5.0ppm) and BA (0.2, 1.0 and 5.0ppm), and then cultured for 8 weeks. The grown bulblets could be classified into three types; normal type, abnormal type-I and abnormal type-II. The morphology of normalbulblets was comparable to bulblets that formed on mother scales cultured in vitro. The bulblets of abnormal type-I were globular and the scale grew more slowly than that of normal ones. Scale of the type-II became dropsy and grew very slowly.
2. The regenerated bulblets which were cultured on a medium of 0.1 ppm NAA and 0.01 ppm BA gained the most fresh weight and had the most and longest roots per bulblet compared to the other treatments. Leaf emergence was advanced by the medium of 0.01 ppm NAA and 0.1 ppm BA. Histologically, root tips of bulblets grown on the medium of 1.0 ppm NAA and no BA for 8 weeks had two central cylinders, and a large hollow core in the cortex. Cracks in the epidermis also developed on this medium.
3. When the bulblets with scale leaves were cultured on the medium of 0.1 ppm NAA and no BA for 4 weeks, they has grown into a plantlet with roots.
We conclude that the combination of 0.1 to 0.01 of NAA and BA, respectively, were optimum for the growth and rooting of bulblets.

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The effectiveness of ethanol extracts from different leafy vegetables and commercial phenolic compounds in degrading chlorophyll (Chl) in a model system using commercial horseradish peroxidase was determined in vitro.
The amount of Chl degradation ranged widely among the leafy vegetables with parsley and mitsuba ethanol extracts having 70 and 60 fold greater activity than that of the garland chrysanthemum extract respectively, which were the extremes among the eight leafy vegetables.
Among sixteen commercial phenolic compounds studied, Chl degradation occurred only with apigenin (flavone), apigetrin (apigenin-7-glucoside), naringenin (flavanone), p-coumaric acid (monophenol) and resorcinol (m-diphenol). These results indicate that Chl degradation in the peroxidase-hydrogen peroxide system is dependent on the type of phenol, specifically those which have a hydroxy group at the p-position.
The only degraded Chl product noted in the HPLC chromatogram, when using p-coumaric acid, was 10-hydroxychlorophyll a (Chl a-1). The amount of Chl a-1 accumulated was minimal, compared to the amount Chl degraded, and implies that most of the Chl was degraded to a colorless product without the accumulation of Chl a-1 as an intermediate.

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Stored shredded onions showed severe browning when they were steamed or boiled during further processing. The effects of storage temperatures and bacterial infection on the browning of heated shredded onion were investigated.
1. Freshly shredded onions did not discolor immediately after being steamed or boiled, whereas samples stored at 20°, 8°, 1°Crequired 2, 5 to 7, and 14 to 19 days, respectively to turn equally brown after heat-treatment.
2. The evolution of characteristic aroma of onions, dipropyl-disulphide, decreased quickly within 12 days at all storage temperatures, whereas hydrogen sulfide increased sharply when shredded onions showed the heat browning.
3. Phenolic compounds increased at the beginning of storage at all temperatures. Concentrations of free amino acids decreased as the discoloration intensified during storage at 8° and 20°C; they did not change at 1°C. Glucose, fructose, and sucrose contents increased slightly during the initial storage period, but they decreased as the tissues turned brown. Carbonyl compounds reacted with 2, 4-dinitrophenylhydrazine increased in the raw shredded onions during storage at 20 °C. More the compounds reacted in steamed onion than in the raw ones.
4. The bacterial count on the surface of shredded onions reached 10⁷ per gram, concurrent with browning at all storage temperatures. The growth of microbial colonies and browning after heat treatment on shredded onions pretreated 70% ethanol were retarded 2 to 3 days compared to those on non-treated onion samples kept at 20 °C.
The juice extracted from highly infected shredded onions became highly discolored, whereas extracts from bacterial culture media turned just slightly brown. These observations suggest that browning of steamed or boiled shredded onions is initiated by bacterial infection during storage, and also suggest the browning pigments do not come from bacteria but from infected shredded onion.

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A rapid and simple method for extracting internal ethylene from excised apple tissue and its quantitative determination are described. The method is suitable for correlating the ethylene concentration with the physiological status of the plant tissues. One advantage was that the time required for the tissue excision, vacuum extraction of ethylene, and injection of a gas sample into a gas chromatograph was about a minute. The method provides accurate and reproducible results, i.e. ca. 80% or more of the internal ethylene in apple tissue can be extracted and determined. Another advantage of this method is that the tissue from which ethylene was extracted is still available for further analyses.
The method was applied to the study ethylene regeneration in apple tissue after the removal of the internal ethylene. The formation of ethylene in apple tissue increased after the existing ethylene was removed led us to propose that ethylene synthesis is governed by a feed-back inhibition. The inhibition (ca. 20%) of ethylene formation was significantly related to the level of internal ethylene in apple tissue.

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Root storability of 'Beniaka' and 'Beniazuma' sweet potatoes was investigated as related to root composition and plant growth before harvest. Percentage of marketable roots after storage of 6 months at 13 °C was high in the roots which contained proteins at 0.4 g•100 g^-1FW and higher in 'Beniaka', and at 0.8 g•100 g^-1FW and higher in 'Beniazuma' at harvest. Percentage of marketable roots after storage was also related to the fresh weight of plant tops (tFW•ha^-1) and N content of whole plants (kg•ha^-1) at harvest. However it didn't show significant relationship with skin color and starch content. Plants with top/root (T/R) ratios of 0.8 to 1.3 at harvest produced roots of high storability and good quality in the two cultivars. These results indicate that root protein contents and T/R ratios could be useful guides for judging the storability of harvested sweet potato roots.

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