Journal of the Japanese Society for Horticultural Science
Online ISSN : 1880-358X
Print ISSN : 0013-7626
ISSN-L : 0013-7626
Volume 59 , Issue 4
Showing 1-23 articles out of 23 articles from the selected issue
  • Hiroaki Inoue, Bunjiro Takahashi
    1991 Volume 59 Issue 4 Pages 703-710
    Published: 1991
    Released: July 05, 2007
    1. In order to determine avocado trees (Persea americana Mill.) flower morphology and abnormality percentages in Japan, flowers of the cultivars ‘Zutano’, ‘Bacon’ and ‘Fuerte’ were studied by scanning electron microscope (SEM) in 1981-1983.
    2. The normal flower was as follows. 1) Perianth number was six. 2) There were nine stamens, three in each of three whorls, each anther with four pollen sacs. The third stamen whorl had a pair of nectaries attached to each filament. 3) The fourth (innermost) stamen whorl has changed its function, having evolved into three staminodes. 4) At the flower center is a primitive pistil.
    3. Flower abnormality was most common in the pistil, including no pistil, short style, naked ovule, curved style, excess style number. The most common pistil abnormality was curved style, followed by naked ovule and style number, for all three cultivars. The maximum abnormality percentages were: Curved style, 87.8% in ‘Zutano’, naked ovule, 35.6% in ‘Fuerte’ more than one style, 11.1% in ‘Bacon’.
    4. Stamen number ranged from 1 to 13, usually near the normal 9. Flowers abnormal in this respect varied among the three cvs. from 11.3 to 30.8% in 1981.
    5. Number of perianth parts ranged from 3 to 11, with abnormal numbers usually a little greater than the normal 6. Abnormal flowers varied from 0.7 to 15.3% in 1982, among the three cvs.
    6. Abnormalities involving these various flower parts were observed in all combinations, including single flower abnormal for all of: Perianth parts plus stamen number plus style number plus curved style plus naked ovule.
    7. In terms of flowering date, perianth and stamen abnormalities were more common in early and mid-season flowers, whereas late bloom was associated more often with pistil abnormalities.
    Download PDF (1689K)
  • Yuji Udagawa, Tadashi Ito, Kiyoshi Gomi
    1991 Volume 59 Issue 4 Pages 711-717
    Published: 1991
    Released: July 05, 2007
    This experiment was undertaken to find the effects of root temperature on apparent absorption of water and uptake of nutrients of ‘Reiko’ strawberry plants grown hydroponically. The roots were exposed to 8°, 13°, 18°, and 23°C.
    1. The rate of water absorption was apparently hastened by higher root temperature at the beginning of treatment and subsequently decreased.
    2. Higher nutrient uptake resulted at the beginning of the experiment by exposing roots to higher temperature. Nutrient uptake by strawberry roots exposed to 8°C gradually increased over 5 days, whereas it decreased in those exposed to 18° or 23°C.
    3. After 11 days, the most rapid nutrient uptake by roots was recorded at 18°C. The uptake of P, Ca, Mg, NO3-N, and K was suppressed in that order at lower root temperature; that of NO3-N, Mg, Ca, K, and P was suppressed in that order at higher root temperature 11 to 31 days after experiment was started.
    4. The highest inorganic nutrient accumulation by whole plants was recorded in plants whose roots were exposed to 18°C. The Ca, P, K, and Mg content per plant decreased with decreasing root temperature. The significant decreases in N and Mg contents were observed in plants whose roots were in nutrient solutions kept at 23°C rather than those roots bathed at 18°C.
    Download PDF (793K)
  • Shinji Monma, Katuya Takada
    1991 Volume 59 Issue 4 Pages 719-726
    Published: 1991
    Released: July 05, 2007
    Inheritance of soluble solids and acidity and relationships between soluble solids, acidity, and other nine characters were studied in five F1 progenies of strawberry.
    1. Soluble solids of most seedlings were within range of parental cultivars in four F1 progenies, whereas many seedlings with high soluble solids were observed in a progeny resulting from a cross between parents both having high soluble solids.
    2. A mean soluble solids contents in each of F1 progenies was similar to or lower than mid-parental value. This result shows partial or incomplete dominance for the low soluble solids character.
    3. A high frequency of F1 seedlings with low acidity was observed in progenies crossed between low-acid and high-acid parents. On the other hand, seedlings with higher or lower acidity than parents were observed in progenies crossed between low-acid parents.
    4. Among the five F1 progenies, the means of acidity in four F1 progenies were nearly identical to or lower than mid-parental value. This suggests that the low-acid character is partially or incompletely dominant. However, the mean of acidity in one F1 progeny was higher than the parents, and this suggests heterosis for high acidity in some combinations.
    5. The broad-sense heritabilities for both soluble solids and acidity are high. This suggests that there are large genetic variations for soluble solids and acidity in F1 progenies.
    6. Negative correlations exist between soluble solids contents and yield (-0.33**--0.62**) or yield per 1, 000cm2 of leaf area (-0.43**--0.70**). On the other hand, positive correlations exist between soluble solids and plant height or leaf area.
    7. Negative correlations exist between acidity and soluble solids-acid ratio (-0.58**--0.85**) and between acidity and yield (-0.01--0.43**) or yield per 1, 000 cm2 of leaf area (-0.04--0.46**).
    8. In selecting seedlings possessing good flavor and high soluble solids, yield, leaf area and plant height should also be considered.
    Download PDF (908K)
  • Yuichi Yoshida, Michio Ohi, Kohei Fujimoto
    1991 Volume 59 Issue 4 Pages 727-735
    Published: 1991
    Released: July 05, 2007
    Yield components and occurrence of fruit malformation in ‘Ai-Berry’ (Fragaria×ananassa Duch.) were investigated with two rates of nitrogen application (0 and 100kg/ha) and six kinds of nursery plants; two kinds of pot-grown plants (grown at 20 and 1200m in elevation) and four kinds of field-grown plants with two rates of nitrogen application (0 and 60kg/ha) and two rooting time (late July and late August).
    Nitrogen application (100kg/ha) hastened flowering and increased the number of flowers on the 1st inflorescences. However, fruit malformation occurred more severely than in plants without nitrogen application and increase in ratio of small fruits (<20g) resulted in reduction of total yield.
    Highest yield of normal large fruits (_??_30g) was obtained in smallest field-grown plants (rooted late August without nitrogen application in the nursery). Nitrogen application was less effective in these plants. Pot-grown plants and field-grown plants rooted in late July bore more flowers on the 1st inflorescence but produced smaller fruits than others.
    Yield of total and normal large fruits were negatively correlated with the number of flowers on the 1st inflorescence.
    Download PDF (980K)
  • Tomohiro Yanagi, Yasaburo Oda
    1991 Volume 59 Issue 4 Pages 737-743
    Published: 1991
    Released: July 05, 2007
    The effect of long-day photoperiod on inflorescence production of 20 octoploid cultivars and strains in genus Fragaria was examined. Test materials consisted of 16 non- and everbearing cultivars of Fragaria×ananassa Duch. and four wild strains of F. chiloensis and F. virginiana.
    In Exp. 1, five non-chilled plants of each cultivar and strain were grown under 24-hr daylength (continuous light) from August 27 to December 25, 1986. In Exp. 2, five pre-chilled plants of each cultivar and strain were grown under 24-hr or natural daylength (Sakai City has an average of 11-hr daylight in early February and 14.5-hr daylight in June.) in a heated greenhouse that was kept at a minimum nightly temperature of 10°C from February 14 to June 25, 1987. The flowering date of each inflorescence was recorded for both experiments.
    1. The everbearing cultivars, ‘Arapahoe’, ‘Ostara’, ‘Rabunda’, and ‘Revada’, produced inflorescence under 24-hr daylength in both experiments. Hence these cultivars are able to initiate flower buds under continuous light.
    2. Under the same continuous light regimen, no inflorescence was formed in ‘Lassen’, ‘Golerra’, ‘Senga Sengana’, ‘Fukuba’, ‘Hokowase’, ‘Morioka 16’, ‘Reiko’, ‘Shuuka’ and two wild strains of ‘chiloensis 1’ and ‘virginiana 2’ during both experiments. Hence these cultivars and strains are considered short-day or June-bearing types.
    3. ‘Aiko’, ‘Kletter’, ‘Tioga’ and the wild strain ‘virginiana 1’ produced inflorescence under 24-hr daylength in both experiments, but at later dates than the previous everbearing types. Therefore, it seems that these cultivars and strain are less sensitive to long-day photoperiods for floral initiation than the other June-bearing cultivars.
    4. The inflorescence production of ‘Redgauntlet’ was inhibited by the 24-hr daylength but was induced to flower under natural daylengths. On the contrary, ‘chiloensis 2’ formed inflorescence under a 24-hr photoperiod but did not flower under a natural photoperiod. This indicates that the wild strain is a long-day type.
    Download PDF (850K)
  • Akio Tazuke, Ryozo Sakiyama
    1991 Volume 59 Issue 4 Pages 745-750
    Published: 1991
    Released: July 05, 2007
    Studies on the relationships between growth rate in volume and respiration rate of cucumber fruits attached on the vine were begun when they were about 9cm in length.
    As fruits grew, those held in individual constant temperature chamber in which the temperature was maintained between 10° to 35°C showed a decrease in respiration rate per fruit volume (R/V) without exhibiting an apparent diurnal fluctuation. The R/V for the first day increased linearly as the fruit temperature became higher. Daily mean values of R/V for the whole measurement period were linear to the relative growth rate (RGR) in volume with the same regression line irrespective of fruit temperature (r=0.95). The intercept of R/V at RGR=0 was comparataively small.
    The amount of respired CO2 (ΔR) from fruit, which varied at different temperatures and age of fruit, was proportional to the increment of fruit volume which occurred during the same period (ΔV), with a regression equation having a proportionality constant of 13.2mg CO2cm-3 irrespective of fruit temperature (R2=0.95). Overall conversion efficiency estimated using the proportionality constant obtained above was 86% and it was influenced little by fruit temperature.
    The proportionality between ΔR and ΔV indicated that the respiration rate of fruit can be used to monitor nondestructively the fruit growth in dry weight. Consequently, in modeling fruit growth of cucumber, separation of fruit respiration into growth and maintenance components is practically unnecessary.
    There was no difference in the relationship between growth in volume and respiration in two cucumber cultivars, i.e., ΔR/ΔV was nearly constant.
    Download PDF (760K)
  • Satoshi Terabayashi, Ken Takii, Takakazu Namiki
    1991 Volume 59 Issue 4 Pages 751-755
    Published: 1991
    Released: July 05, 2007
    Water and nutrient (NO3-N, PO4-P, K, Ca and Mg) uptake by tomato (Lycopersicon esculentum Mill. cv. Ohgata-Fukuju) plants during the day (7:00 to 19:00) and night (19:00 to 7:00) was measured. Measurements were made for 4 days on each plant at 3 developmental phases: a) 8-leaf seedling, b) the first truss was flowering, and c) when fruits were growing.
    URN (ratio of the uptake rate during the night to that of the 24-hr day, expressed in percentage) of phosphate was highest as compared to those of water and nutrients at all plant growth stages. URN of nutrient was highest when the first truss was flowering and lowest when the fruits were growing. URN of phosphate was relatively high as compared to that of water at the fruit growing stage.
    These results show that URN of nutrients changes depending on the growth stage of tomato plants and may reflect the nutritional status and possibly the demand for certain nutrients by tomato plants grown hydroponically.
    Download PDF (601K)
  • Sachiko Matsubara, Ichiro Kimura
    1991 Volume 59 Issue 4 Pages 757-762
    Published: 1991
    Released: July 05, 2007
    Correlation between growth and dormancy, and changes in abscisic acid (ABA) levels was studied in onion (Allium cepa L. cv. Awaji Chukodaka). ABA in the growing tip, leaf, bulb and root tissues was identified by ECD gas chromatography. ABA was detected in all tissues and their levels varied depending on the developmental stages of onion. Higher concentration of ABA was observed in the growing tip and was about twice that in other tissues. An increase in endogenous ABA level commenced at the onset of bulbing and attained the highest level at the time of lodging. Although a high level was observed during the dormant stage, the level gradually decreased during storage period. It was at its lowest at the end of dormancy, one month after storage. Upon sprouting, ABA level increased again in sprouted leaves.
    In vitro bulbing of plantlets from apices was induced by the exogenous application of NAA or BA, but it was neither promoted nor inhibited by ABA or GA treatments.
    Download PDF (695K)
  • Fu-Chang Guo, Yukihiro Fujime, Tadahiko Hirose, Toru Kato
    1991 Volume 59 Issue 4 Pages 763-770
    Published: 1991
    Released: July 05, 2007
    The effects of shoot number and raising period of seedlings on growth, fruiting and yield of sweet pepper were investigated. In Experiment I, 30-day or 45-day seedlings of ‘California-Wonder’, ‘Shin-sakigake’ and ‘Shishito’ were planted in the plastic house. In Experiment II, 33-day seedlings of ‘Eiko’ were used. The plants were trained with two or four shoots in Experiment I and one, two or four shoots in Experiment II. The total number of shoots in each plot (9m2) were kept in same number by changing the plant number.
    The more the 2-training shoot plant is in plot, the more the fruit number and yield per plot were increased. The increase in fruit number and yield in ‘California-Wonder’ and ‘Shinsakigake’ was more notable than in‘Shishito’. Except for ‘California-Wonder’, the fruit number and yield of 30-day seedlings were higher than those of 45-day seedlings.
    The fewer the training shoot number is, the more the top and root dry weights were increased. The total dry weight of 30-day seedlings was increased as the number of training shoots increased. The 30-day seedlings had thicker roots than the 45-day seedlings except for the 2-training shoot plants of ‘California-Wonder’. Highly signicant correlations were recognized between the yield and the number of thick roots or the total leaf area in each cultivar.
    The percentage of normal fruits, the mean fruit weight and fruit thickness were increased as the number of training shoots decreased. The percentage of normal fruits and the mean fruit weight in 30-day seedlings were higher than those in 45-day seedlings.
    Results of this study on four sweet pepper cultivars showed that with more plants, each with fewer training shoots, harvestable fruit and the total yield per plot increased. Fewer training shoots resulted in an increase in the number of thick roots, total dry weight and total leaf area per plot, thus the enhancement of photosynthesis.
    Download PDF (929K)
  • Yoshihiro Shishido, Cheon Jong Yun, Tsutomu Yuhashi, Norio Seyama, Shi ...
    1991 Volume 59 Issue 4 Pages 771-779
    Published: 1991
    Released: July 05, 2007
    Changes in rates of photosynthesis, translocation, and distribution pattern of 14C-assimilates in leaves during their development and the contribution of individual leaves to the accumulation of photosynthates in various sinks were investigated by using tomato plants.
    The photosynthetic rate of the 3rd and 7th leaf gradually decreased with their ages, however, the amounts of photosynthates produced per leaf gradually increased with the increase of leaf area. Therefore, the amounts of photosynthates reached maximum just before full expansion of each leaf.
    Most of assimilates were distributed to near sink as a main sink. Furthermore, the relationship between source and sink likely changed with the developmental stages of roots, shoot and fruits resulting in difference in sink strengths. Thus, competitiveness among sinks changed according to the relative gradients between them and the source.
    The contribution of each leaf to the accumulation of assimilates by each sink was calculated by the total amount of assimilates and the sum of the distribution of 14C-assimilates from each leaf. The inflorescence was supplied 60-80% of its accumulation by 2 to 4 adjacent leaves. Furthermore, the maximum contribution rate from one leaf seemed to be about 30%. The peak efficiency of a leaf to supply a sink corresponded to the time when the sink was enlarging most rapidly.
    Download PDF (1029K)
  • DE Yue, S. Kusumoto, Hideo Imanishi
    1991 Volume 59 Issue 4 Pages 781-785
    Published: 1991
    Released: July 05, 2007
    It is impossible to force Dutch iris ‘Blue Magic’ early and to obtain cut flowers with long flower stalks and short leaves by using the normal method of precooling at 9°C for 9 weeks. After exposing bulbs to ethylene at 10μl/liter for more than 24hr to ensure flowering, they were subjected to precooling at different temperatures and for various durations to improve flower quality.
    Flower stalk lengthened when bulbs were exposed for 3 weeks at 15°C before they were precooled at 9°C. Leaf length decreased with increasing durations of precooling at 9°C. Foliar applications of 5mM silver thiosulfate (STS) 4 weeks after planting precooled bulbs resulted in enhanced extension of flower stalks.
    In conclusion, cut flower of ‘Blue Magic’ with good quality can be obtained by precooling bulbs at 15°C for 3 weeks and at 9°C for 7 to 8 weeks and then spraying the emerging leaves 4 weeks after planting with 5mM STS.
    Download PDF (523K)
  • Takashi Hosoki, Mitsuhiro Seo, Morihito Hamada, Katsuhiro Itoh, Kunio ...
    1991 Volume 59 Issue 4 Pages 787-793
    Published: 1991
    Released: July 05, 2007
    A new horticultural classification of herbaceous peony is offered, using a multivalent analysis based on morphological and ecological data and paired affinity (PA) values of flavone and flavonol compounds in the petals. Cultivars of Paeonia officinalis are classified in one group by both methods, whereas those of Paeonia lactiflora are classified to another by the multivalent analysis. The Japanese and Western cultivars of Paeonia lactiflora are further divided into separate subgroups. Paeonia obovata and Paeonia japonica, which are closely related taxonomically, are also shown to be very close when classified morphologically and by multivalent analysis.
    Thus, the multivalent analysis based on the morphological and ecological data and PA value of flavone and flavonol in the petals is now shown to be a useful tool for assorting and/or tracing the parentages of herbaceous peony cultivars of unknown origin. Such tasks are impossible using the previous classification based solely on flower shapes.
    Download PDF (604K)
  • Motoaki Doi, Takashi Morita, Yasuaki Takeda, Tadashi Asahira
    1991 Volume 59 Issue 4 Pages 795-801
    Published: 1991
    Released: July 05, 2007
    To determine flowering responses with respect to rosette formation and flower malformation, Gypsophila paniculata L, plants at different developmental stages were exposed to high temperatures after exposure to winter chilling.
    Initial exposure of vegetative shoots to 30°C from 6:00 to 18:00 and 25°C from 18:00 to 6:00 from 31 Mar. to 10 Apr. resulted in rosette formation in those plants which require long durations of winter chilling such as ‘Perfecta’ and ‘Bristol Fairy’ line 20. Rosette formation occurred even when these plants were grown under optimum conditions. About 50% of the ‘Diamond’ and ‘Bristol Fairy’ line 03 shoots formed rosettes after exposure to 30°/25°C; these cultivars require a relatively lengthy exposure to winter chilling to satisfy their rest requirement. Conversely, ‘Flamingo’, ‘Red Sea’, and ‘Bristol Fairy’ line 08 which require a little chilling did not form rosettes but bloomed.
    Exposure to high temperature immediately after the onset of flower bud initiation resulted in shorter flower stalks and fewer nodes with inflorescences on the main stem, but no other abnormal morphological changes were observed.
    Flower malformation was induced when shoots were exposed to high temperature around 30 Apr. when stamen initiation in the terminal floret was occurring. Anatomical studies revealed that the flower malformation was related to an abnormally extended period of transformation of stamens to petaloid structures prior to anthesis. Meristematic activities of the stamen primordia were prolonged after an exposure to high temperature at this stage of floret formation. Consequently, cluster-like petaloid stamens formed around the meristematic tissue that resulted in increased number of petals. Malformed flowers occurred more frequently in cultivars and vegetative lines which require longer durations of chilling.
    These results show that the exposure to high temperature neutralizes the chilling effects for reproductive growth and induces the formation of rosettes. Both rosettes and malformed flowers may be expressions of the transition from the reproductive growth (anther) to a vegetative one (petal) at the meristematic level, as a result of exposure to high temperature.
    Download PDF (923K)
  • Toshihiko Eguchi, Hiroshi Okubo, Kunimitsu Fujieda, Shunpei Uemoto
    1991 Volume 59 Issue 4 Pages 803-814
    Published: 1991
    Released: July 05, 2007
    Isozyme variations of 7 enzyme systems among representatives of indigenous Camellia japonica found growing in 12 geographical regions in Asia were examined to measure the genetic divergence among their intraspecific taxa.
    The mean genetic identity value between any pairs of regions is 0.77, which is low as compared to the conspecific values of other outcrossing species. This condition is attributed to the very divergent allelic variation that ssp. rusticana possesses as compared to vars. hozanensis and japonica, both of which belong to ssp. japonica. On the contrary, only a small difference exists between var. hozanensis and var. japonica, and the genetic data of these two varieties is reflected by the electrophoretical features of the progenitor/derivative pair. Comparisons between electrophoretic phenotypes in C. japonica with those in Camellia species lead us to two possibilities on how the phylogeny of intraspecific taxa of C. japonica might have evolved. 1) Subspecies rusticana arose in earlier times than did vars. hozanensis and japonica, if their ancestors had been the same. 2) Varieties hozanensis and japonica arose with introgressive hybridization among different sections of the genus Camellia.
    Download PDF (1082K)
  • Genjiro Mori, Hisami Kawabata, Hideo Imanishi, Yoshihiro Sakanishi
    1991 Volume 59 Issue 4 Pages 815-821
    Published: 1991
    Released: July 05, 2007
    The bulb structure, and the growth periodicity of plants grown outdoors were observed using Leucojum aestivum which comes into bloom in early spring and L. autumnale which blooms in August.
    1. A bulb shows a sympodial branching system, each unit of which is composed of 6-8 or 9-10 foliage leaves in L. aestivum or L. autumnale, respectively, and a lingulate scale, and terminates in an inflorescence. The bases of foliage leaves, which encircle the axis and gradually enlarge, serve as a food storage organ.
    2. When the spathe leaf is being initiated at the apex during the latter part of May, a lateral bud is formed in the axil of the uppermost leaf, which develops into the next sympodial unit.
    3. In both species, leaf initiation continues from spring to autumn. Leaves and the primary inflorescence of L. aestivum emerge simultaneously from early to mid-February just before flowering. The leaves wither acropetally from the lower to upper ones and are completely dry by the end of May. In L. autumnale, leaves appear in September and October after flowering and die progressively from the lowest to the apical leaf between December and July. The foliar canopy consists of a few leaves which formed in the upper nodes of the sympodial unit with the flower bud and those which formed in the basal nodes of the next sympodial unit.
    4. Initiation of flower bud started in mid-May in L. aestivum and at the end of May in L. autumnale. Inflorescence growth of L. autumnale progressed faster than did that of L. aestivum. Carpel primordia in the first floret of L. autumnale were observed in early June, and pollen tetrads in the latter part of July. The inflorescence bloomed in early August.
    5. Carpel differentiation in the first floret of L. aestivum began during the latter part of June but ceased further development until the middle of October. Pollen tetrads were formed in the latter part of February and anthesis occurred in March. In both species, floral parts of the secondary or tertialy inflorescencee differentiated after a slight delay following the formation of florets in the primary inflorescence.
    Download PDF (890K)
  • Midori Fujioka, Masahiro Kato, Fumika Kakihara, Satoru Tokumasu
    1991 Volume 59 Issue 4 Pages 823-831
    Published: 1991
    Released: July 05, 2007
    Pelargonium (Pelargonium × domesticum Bailey) cultivars are usually propagated by cuttings because they root easily and many of them do not produce viable seeds. To obtain seed-propagation type with diverse flower colors, seed fertility was improved by transferring genes from other sources such as the scented-leaved geraniums. Consequently, many hybrids between various cultivars of pelargoniums and scented-leaved geraniums were produced (7). The present investigation was conducted to categorize flower colors and determine their pigment composition, using 27 pelargonium cultivars, interspecific hybrids and their progenies.
    Analysis of floral pigments revealed the presence of six kinds of anthocyanidins: Pelargonidin (Pg), cyanidin (Cy), peonidin (Pn), delphinidin (Dp), petunidin (Pt), and malvidin (Mv). However, pigments of blotches are mainly Dp, Pt, and Mv. Moreover, amount of pigments is 5-10 times to that of non-blotch parts. Based on their composition, cultivars and hybrids were classified into nine types: (1) Those having mostly Pg (more than 80%); (2) Pg-Cy-Pn-Mv (small amount); (3) Pg-Pn-Mv (less than 40%); (4) Pg-Pn-Mv (more than 40%); (5) Pg-Cy-Pn-Dp-Pt-Mv (all anthocyanidin existing type); (6) Cy(trace)-Pn(trace)-Dp-Pt-Mv; (7) Dp-Pt-Mv; (8) mostly Mv; and (9) acyanic.
    In pelargonium, the pigment Pg is the most prevalent and abundant one in the expression of flower color. A high correlation (r=0.900***) was obtained between the content of Pg and the hue value of flower color. The content of Dp was also positively correlated with the hue value (r=0.858***).
    However, if‘Dark Venus’color type containing all six kinds of anthocyanidins was added to data for the calculation of correlation coefficients, the correlations between each anthocyanidin and hue value became weaker or non-significant (Pg: r=0.541***, Dp: r=0.028). On the other hand, a highly negative correlation (r=-0.883***) was found between the content of Mv and the hue value, even when‘Dark Venus’color type was added to data.
    There was a negative correlation between the content of total anthocyanidins and the lightness of flower color. The regression equation was: L*=70.38-7.40logA, in which L* is the lightness and A is the anthocyanidin content. The correlation coefficient, r, of-0.912*** was obtained.
    Download PDF (876K)
  • Genjiro Mori, Hisami Kawabata, Hideo Imanishi, Yoshihiro Sakanishi
    1991 Volume 59 Issue 4 Pages 833-838
    Published: 1991
    Released: July 05, 2007
    This study was carried out to clarify the effects of temperature during different developmental stages on the initiation and development of flower buds of Leucojum aestivum and L. autumnale which bloom in March and August, respectively.
    1. Flower initiation occurred at any temperature from 10°to 30°C, but the optimum temperature for flower initiation and further differentiation of floral organs was 20°-25°C in both species.
    2. In L. autumnale, development of flower buds from carpel formation stage to flowering progressed more rapidly at 20°-25°C than it did at 30°C, and flower buds ceased developing and blasted at 10°-15°C.
    3. In L. aestivum, further development of flower buds after carpel formation stage was inhibited when plants were placed at or above 20°C. Shifting the plants to 10°-15°C resulted in anthesis. However, plants had to be kept at 10°-15°C up to anthesis, otherwise they failed to flower. This result indicates that a temperature range of 10°+15°C is indispensable for maturation of flower buds and elongation of scapes.
    4. From these results, it was proved that the difference in flowering time between L. autumnale and L. aestivum under natural conditions is ascribed to difference in response of flower buds to the temperature after the formation of carpel initials, i.e., flowering occurred rapidly at the temperature range of 20°-25°C in L. autumnale, whereas an exposure to temperatures ranging between 10°-15°C was required for flowering in L. aestivum.
    Download PDF (738K)
  • Takahiro Hayashi, Yoshimoto Wakahara, Kuniyoshi Konishi
    1991 Volume 59 Issue 4 Pages 839-845
    Published: 1991
    Released: July 05, 2007
    The development and composition of compound inflorescences in poinsettia were observed from flower initiation to anthesis at 10-day intervals.
    1. Under short day conditions, the primary cyathium differentiates at the tip of a shoot. Compound inflorescences made up of cyathia, bracts, and the inflorescence axis subsequently develop from axils of upper leaves. We termed each of them as a compound inflorescence unit. The terminal cyathium and upper three compound inflorescence units, which have been called a flower or an inflorescence, are considered a compound inflorescence in this paper.
    2. The differentiation of cyathia and bracts in a compound inflorescence unit show a definite pattern; after the cyathium of the order n forms at the tip of the inflorescence axis of the order n, 2 cyathia and 4 bracts of the order n+1 differentiate from axils of the bracts of the order n.
    3. In the average plant, one of the two differentiated primordia of cyathia and two of the four of bracts continue to abort from third and second order, respectively.
    4. There was a close relation between the position of primordia and their abortion. As a result, a compound inflorescence unit develops as a scorpioid cyme at high order, while primordia differentiate as a dichasium.
    5. When the source/sink ratio of a plant is high, compound inflorescences (flowers) with many-branched axes develop rapidly.
    Download PDF (1449K)
  • Genjiro Mori, Hideo Imanishi, Yoshihiro Sakanishi
    1991 Volume 59 Issue 4 Pages 847-853
    Published: 1991
    Released: July 05, 2007
    In this study, the growth periodicity of Cyrtanthus mackenii grown in unheated glasshouse was clarified and the effects of temperature on the initiation and development of flower buds were investigated.
    1. A bulb shows a sympodial branching system, and each unit of the sympodial branch is composed of a membranous scale and 3 foliage leaves in 1/2 alternate arrangement from the base upwards and terminates in an inflorescence, which bears 5-7 florets. During the growing period from spring to autumn, repeated sympodial branching results in 2 inflorescences being initiated.
    2. In the primary inflorescence, differentiation of the first floret progresses rapidly until the carpel margins fuse to form the ovary in August when further morphological development is suspended until November. The pollen mother cell attains the tetrad stage and the pollen grains mature and become functional between November and January. Anthesis occurs in late January through February. The secondary inflorescence initiated between July and September differentiates floral parts without suspension and comes into bloom in late April through May. Floral part of the tertiary inflorescence differentiates after a three-month delay following the secondary inflorescence, and will progress as described in the primary inflorescence.
    3. Plants did not flower when they were moved from an unheated glasshouse to a heated one kept above 20°C on or before November 10. This result suggests that they have some chilling requirement for flowering.
    4. When plants with inflorescences at carpel formation stage were exposed to chilling at 10°C for 3 weeks or 15°C for 4 weeks, and then shifted to a glasshouse kept above 20°C, they flowered normaly.
    5. After the chilling requirement was fully satisfied, higher temperatures resulted in earlier flowering. However, some depression in the length of scape and the fading of flower colour were observed at 25°C.
    Download PDF (768K)
  • Genjiro Mori, Keiko Nakano, Hideo Imanishi, Yoshihiro Sakanishi
    1991 Volume 59 Issue 4 Pages 855-861
    Published: 1991
    Released: July 05, 2007
    In this study, the growth periodicity of Sternbergia plants grown outdoors was clarified and the effect of temperature on the initiation and development of flower buds was investigated.
    1. The Sternbergia bulb develops a sympodial branching system. Each unit has about 8 foliage leaves and terminates in 2 or 3 inflorescences. The bases of the foliage leaves, except the uppermost leaf, encircle the vertical axis of the bulb and gradually enlarge into scales which serve as food storage organ.
    2. Floret initiation on the primary inflorescence occurs between April and early May. Carpel primordia are visible in early July and the pollen tetrad are formed in early September. Anthesis occurs in late September. Floral differentiation on secondary and tertiary inflorescences follows that of the primary inflorescence after a short delay.
    3. Flower initiation occurs at temperatures between 10°and 30°C, but the optimum range was 20°-25°C. Once initiated, floral differentiation and development progressed most rapidly at 25°-30°C.
    4. The development of flower bud from carpel formation stage to flowering was faster at 20°-25°C than at 30°C. At 10°C flower buds ceased to develop and became blasted.
    5. Bulbs kept at 20°C after July 1, when the main inflorescence attained the carpel formation stage, bloomed earlier but produced fewer inflorescences as compared to those placed at 25°or 30°C from July 1 to August 19 and thereafter shifted to 20°C. This result suggests that bulbs should be kept at 25°-30°C after carpel formation in the main inflorescence to optimize the development of secondary and tertiary inflorescences.
    6. To retard development of flower bud until the Christmas season, bulbs were stored at 5°and 30°C after August 20. Bulbs stored at 30°C and planted in late November flowered in late December when forced in a glasshouse kept above 20°C, but those stored at 5°C did not flower because the flower buds became blasted.
    Download PDF (879K)
  • Fusao Mizutani, Ryuji Hirota, Shoji Amano, Akira Hino, Kazuomi Kadoya
    1991 Volume 59 Issue 4 Pages 863-867
    Published: 1991
    Released: July 05, 2007
    Changes in cyanogenic glycoside content and β-cyanoalanine synthase activity were determined in the flesh and seeds of Japanese plum(Prunus salicina Lindl.) during development. In the flesh, only prunasin was detected at levels as low as 0.6mg/g dw at the earliest sampling date (May 4) and became soon undetectable. Similarly β-cyanoalanine synthase activity, which showed 0.3μmol H2S/g fw/hr on May 4, gradually decreased to undetectable levels in late May, but a slight increase was noted during ripening. On the contrary, seeds had total amounts of cyanogenic glycosides as high as 75-100mg/g dw throughout the season. Prunasin was predominant in young seeds but the content began to reduce in early June and became barely detectable in early July. On the other hand, amygdalin appeared in early June and then increased rapidly to the maximum level (100mg/g dw) in late June. Such a corresponding increase in amygdalin content with decreasing prunasin concentrations suggests the conversion of prunasin to amygdalin. β-Cyanoalanine synthase activity in the seed was considerably higher than in the flesh. The activity in the seed was kept consistent at early stages (5.6-7.6 μmol H2S/g fw/hr) but further increased in parallel with the increasing amygdalin concentrations to the maximum level as high as 100μmol H2S/g fw/hr.
    Download PDF (553K)
  • Naoki Yamauchi, Fumio Hashinaga, Saburo Itoo
    1991 Volume 59 Issue 4 Pages 869-875
    Published: 1991
    Released: July 05, 2007
    Changes in concentrations of chlorophylls (Chls) a and b and their derivatives and peroxidase and chlorophyllase activities were determined to elucidate the pathway of Chl degradation in developing and stored kabosu (Citrus sphaerocarpa Hort. ex Tanaka) fruits.
    Surface color of kabosu fruits gradually turned from green to yellow with fruit development. The level of phenolic compounds involving in Chl degradation and peroxidase activity increased concurrently.
    The Chl contents sharply decreased concurrent with the degreening of stored kabosu fruits. The patterns of HPLC tracings derived from extracts of fresh kabosu fruit revealed the presence of pheophytin a, 10-hydroxychlorophylls a and b, and chlorophyllides a and b, as Chl derivatives. These Chl derivatives in rind extracts gradually disappeared as degreening progressed during storage at 20°C; some were barely detectable on day 50. Peroxidase activity in fruits held at 20°C increased appreciably during the first 20 days of storage and then decreased. Chlorophyllase activity in the rind of fruits stored at 20°and 4°C increased slightly on day 20 but subsequently decreased.
    It is inferred from these results that most Chls in kabosu fruits are degraded into a colorless product through a peroxidase pathway.
    Download PDF (910K)
  • Masayoshi Sawamura, Tomoko Miyazaki, Xiaolin Yu
    1991 Volume 59 Issue 4 Pages 877-883
    Published: 1991
    Released: July 05, 2007
    Some treatments were examined to prolong freshness in green-mature Yuzu (Citrus junos Tanaka) fruits stored in polyethylene (a type of linear low density plastic) bags.
    1. Degreening of fruits had already begun on the 35th day of storage at 5°C, but no chilling injury occurred over a period of 110 days. All injuries occurred on the 35th day of storage at 0°C. There was not a great difference between a 20μm and a 30μm thick film in the degreening index and the percent of injury.
    2. The thickness of polyethylene film was 30μm in the case of storage at 2°C. The storage with a freshening agent prolonged the period for reaching 100% chilling injury for 1 to 3 months longer than that without it. The period without injury lasted at least 6 months when the fruits were stored with a freshening agent after they had been preliminarily dipped in hot water at 50°C for 2 to 5min. These storage conditions did not affect the degreening of fruits, since there was no significant difference between initial values and those of 6-months later for the color indexes (a and b) based on the L-a-b system. The fruits pretreated with water at 30°, 40°and 20°C (as a control), however, suffered chilling injury in 3 to 4 months, even though accompanied with a freshening agent.
    Download PDF (850K)