Journal of the Japanese Society for Horticultural Science
Online ISSN : 1880-358X
Print ISSN : 0013-7626
ISSN-L : 0013-7626
Volume 63 , Issue 4
Showing 1-23 articles out of 23 articles from the selected issue
  • Shuji Shiozaki, Yoshihito Ueda, Tsuneo Ogata, Shousaku Horiuchi, Kenji ...
    1995 Volume 63 Issue 4 Pages 703-710
    Published: 1995
    Released: May 15, 2008
    The correlative effect of gibberellin A3 (GA3) and indole-3-acetic acid (IAA) on the development of 'Delaware' grape ovary was examined in vitro. GA3 induced a significant increase of the ovary fresh weight, proportionate to its concentration; IAA and tryptophan (Trp), a precursor of IAA, had little effect on increasing in fresh weight of the ovary. GA3 + IAA increased the ovary fresh weight more than GA3 or IAA alone. The fresh weights of the GA3 or IAA treated ovaries increased 1.08- to 1.56-fold over the control, whereas those treated with the combination of GA3 and IAA increased 1.85- to 2-fold over control after a 9-10 week-culture. The effect of GA3+ Trp on increasing in fresh weight of the ovary was about the same as that of GA3+IAA. These results indicate that GA3 promotes the ovary development more than IAA and that IAA and Trp enlarge the promotive effect of GA3.
    The ovary development in response to GA3 and GA3 + Trp was partly inhibited by anti-auxins such as N-(1-naphthyl) phthalamic acid (NPA), 2, 3, 5-triiodobenzoic acid (TIBA). Besides inducing an increase of the ovary fresh weight, GA3 increased the content of IAA-like substances in the ovary. From these results, it appears that the effect of GA3 on the ovary development is ascribed not only to its original action, but also to the synergistic action with IAA synthesized de novo.
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  • Yunosuke Shiozaki, Osamu Arakawa, Takuro Kikuchi
    1995 Volume 63 Issue 4 Pages 711-718
    Published: 1995
    Released: May 15, 2008
    Light intensity and fruit distribution within foliar canopies were measured on 'Fuji'/Marubakaido (M. prunifolia Borkh. var. ringo Asami) trees trained to "HU (Hirosaki University) central leader training system" planted at distances of 5 in×3.5 m. The percent instantaneous incident photosynthetic photon flux density (%INPPFD) was measured on overcast days with quantam sensors. Measurements were taken on four vertical plane grids (grid section : 0.5 m×0.5 m) placed through the center of each tree, one directed along the tree row (NE-SW), one at 90 degrees (NW-SE) and two at 45 degrees (S-N, W-E) with the tree row. The number of fruits within the grids were also counted.
    About 7080% of fruits were found on the cross sections of canopy directed at 45 degrees with the tree row; they were well-distributed throughout the sections. The contour lines of INPPFD which extended horizontally with a broad top indicate that light from above as well as from sides of the trees penetrated the canopy.
    The favorable within-canopy light condition was brought about by the characteristic framework of HU central leader trees : the four bottom limbs are directed at 45 degrees with the tree row and slanted at an angle of 45 degrees above the horizontal; the other branches arising from the central leader are kept much shorter than the bottom limbs. The mean depth of leaf canopy favorable for fruit production was estimated to be 1.7 m, which is the same as that we estimated for open-center trees.
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  • Hiroyuki Yamashita, Tadayuki Haniuda, Hisashi Shiba
    1995 Volume 63 Issue 4 Pages 719-724
    Published: 1995
    Released: May 15, 2008
    Zygotic embryos from crosses between tetraploid grape cultivar 'Kyoho' and diploid cultivars 'Rizamat' and 'Sekirei' were rescued at different developmental stages 60 to 70 days after pollination. The immature, mature and abnormal embryos were aseptically excised from the ovules and culture on MS medium without phytohormones in an effort to obtain triploid seedlings.
    1. Most zygotes which advanced to and beyond the torpedo-shaped germinated on MS basal medium, whereas immature and abnormal ones failed to develop. However, the germination of both immature and abnormal embryo improved when they were cultured on a modified MS medium without ammonium salts but supplemented instead with 250, 500, or 1000 mg•liter-1 of casein hydrolysate.
    2. Although most of the germinated embryos stopped growing on these germination media, they initiated to leaf-out or multiple leaf buds after being transferred to a MS medium supplemented with 0.2, 2, or 5 mg•liter-1 of BA; they then formed shoots. When shoots were transferred to MS medium without phytohormones, roots were initiated. Sub-sequently, plantlets were successfully acclimated and established.
    Almost 100% of the mature embryos developed into plantlets, whereas only 10% of the immature ones could be rescued. Therefore, an embryo rescue and culture methods developed by this study would be successfully utilized for obtaining triploid grape seedlings from crosses between tetraploid and diploid cultivars.
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  • Shu-Ang Peng, Shuichi Iwahori
    1995 Volume 63 Issue 4 Pages 725-738
    Published: 1995
    Released: May 15, 2008
    To investigate the possible involvement of calcium in the process of flower differentiation, calcium ion in the cells of apical meristem was detected electronmicroscopically using buds on spurs and vegetative shoots of Japanese pear (Pyrus pyrifolia Nakai) cv. Shinsui as materials.
    1. Cells at samples fixed with glutaraldehyde-formaldehyde and post-fixed with osmium tetroxide, both of which contained pyroantimonate, precipitated many black particles whereas they were not observable in photomicrographs of cells fixed with fixatives without antimonate. Most of the black particles disappeared when the preparations were treated with EGTA which indicate that the black particles are calcium-antimonate complexes. The localization, density and the size of the particles within cells of apical meristem changed dramatically as flower differentiation proceeded.
    2. Density of calcium particles differed depending on the activity of the cells. Until June 5, only a few particles were observed; they were mainly localized in plastids of cells from buds on spurs. The particles subsequently increased, and then decreased temporarily just before the onset of floral differentiation; another increase to a maximum level on June 26 was noted at which time corpus cells became very active judging from dense staining of cytoplasm and increased dictiosomes and endoplasmic reticulum (ER). The particles decreased thereafter through 3 and 10 July and reached a low value on July 17 when calyx primordia began to differentiate.
    3. Ca2+ density in nuclei of cells was low before flower differentiation, but it increased, indicative that floral differentiation was occurring. Within nucleus, Ca2+ distri- buted mainly in nuclear fluid, some in granular region of nucleolus and its releasing materials, but not in the fibrous area of nucleolus, chromosomes or chromatin.
    4. Although Ca2+ is mainly concentrated in the cell wall, its level in the cell wall decreased as Ca2+ in the vacuoles increased at the floral differentiation stage. The vacuole normally contains little Ca2+, but during this period it increased dramatically.
    5. Plastids contained almost all Ca2+ in the cell before June 5, and after that, continued to be one of the main distribution area of Ca2+. But Ca2+ in plastids decreased when Ca2+ in cells markedly increased on June 26. On the other hand, Ca2+ contents in mitochondria, dictiosomes, and ER changed parallel to the changes of Ca2+ in cytoplasm, and increased after flower differentiation stage on June 26.
    6. The size of the Ca2+ particles also changed during flower differentiation. The size became smaller as the flower differentiation proceeded, smallest on July 10, but after that became larger when Ca2+ density rapidly decreased.
    7. Possible role of Ca2 + in the cell of apical meristem in flower differentiation of Japanese pear was discussed.
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  • Mitsuo Awamura, Koji Shoda, Michikazu Hiramatsu
    1995 Volume 63 Issue 4 Pages 739-743
    Published: 1995
    Released: May 15, 2008
    To improve the Pollen germination of caprifig 'VC-180' (Ficus carica L. var. intermedia Shinn ×F. carica L. var. sylvestris Shinn) in vitro, stigmatic exudate from long-styled pistillate flowers of 'Masui Dauphine' (F. carica L. var. hortensis Shinn) was added to a medium.
    1. The optimum pollen germination of 'VC-180' occurred when 2 or 3 pistillate flowers of 'Masui Dauphine' were embedded per cm2 of basal medium (1% agar +10% sucrose) for 3 hours under 5° to 15 °C.
    2. More than 70% of the pollen grains germinated and grew vigorously during a 7-hour-culture kept at 25° to 30 °C.
    3. Pistillate flowers within a syconium (2032 mm diam.) of the second crop of 'Masui Dauphine' figs promoted pollen germination. Likewise, pollen grains from the summer crop of caprifig 'VC-180' germinated regardless of the maturity of the syconium in the presence of the stigmatic exudate.
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  • Daijirou Yahata, Yoshiki Oba, Minoru Kuwahara, Kazunori Matsumoto
    1995 Volume 63 Issue 4 Pages 745-752
    Published: 1995
    Released: May 15, 2008
    The effects of crop load on water stress, yeild, and fruit quality of 13-year-old rootrestricted satsuma mandarin (Citrus unshiu Marc. var. preaecox Tanaka) trees grown indoors were investigated. The trees were heated from early December to late May. The fruits were thinned to a leaf-to-fruit ratio of either 15 (L :F-15) or to 10 (L : F-10) in early April.
    1. Trees with L:F -5 had lighter crops of smaller frutis with higher Brix than had trees with L :F-10.
    2. As fruits ripened in June to July, soil water potential, pF, of L :F -15 plots nearly exceeded those in L :F -10 plbts. The leaf water potential was lower and early leaf abscission was greater on L :F -15 trees than on L :F -10 trees. Thus, satsuma mandarin trees with L :F-15 underwent a more severe water stress than did trees with L :F-10 trees.
    3. The total and reducing sugar contents in the bearing shoots at harvest were significantly higher in the L : F-15 treatment than shoots in the L: F-10 treatment, but there were no differences in the fine roots (< 2 mm diam.). However, no difference in the starch content was observed in shoots and fine roots between the two treatments.
    4. The number and length of shoots appearing after summer pruning in the L:F-10 and L : F-15 trees were nearly equal. In late October and late November, the starch contents of the new shoots were lower in the L :F -10 treatment than in the L : F -15 treatment. No difference existed in the number of flower buds between trees of the two treatments when they were forced in December of the second year.
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  • Kiyohide Kojima, Toshio Takahara, Tatsushi Ogata, Noboru Muramatsu
    1995 Volume 63 Issue 4 Pages 753-760
    Published: 1995
    Released: May 15, 2008
    Growth chracteristics of six citrus rootstocks and their scion/rootstock combinations with 'Ichifumi-wase' and 'Eureka' lemons as tops were investigated.
    1. After September, seedlings of trifoliate orange, Hiryo (Flying dragon), 'Troyer' citrange, and 'Rask' citrange stopped growing, but those of Shiikuwasha and rough lemon continued to grow.
    2. Total root lengths on each of above rootstocks grafted with 'Ichifumi-wase' and 'Eureka' lemons scions increased rapidly from July to October. The length and weight measurements of the branches and leaves, 20 months after grafting, revealed that scions grafted on Shiikuwasha grew best; those on trifoliate orange and rough lemon were intermediate, whereas scions on Hiryo, 'Troyer' citrange, and 'Rask' citrange grew poorly. On all rootstocks, 'Eureka' top grew better than did that of 'Ichifumi-wase'. The root growth is independent of top growth; hence, roots of 'Ichifumi-wase'/trifoliate orange combination grew well, whereas that of 'Eureka'/'Rask' combination grew poorly. The top/root ratio with 'Eureka' as scions was relatively large on all rootstock, attaining a high of 3.0 with Shiikuwasha.
    3. Analyses for ABA, IAA, and GA in shoots and roots of trifoliate orange, Hiryo, and Shiikuwasha revealed that ABA level in trifoliate orange shoots was highest; Hiryo was intermeadiate, and Shiikuwasha had the least. IAA and GA levels in shoots of all rootstocks were nearly equal. ABA concentration of roots was slightly higher in Hiryo than it was in trifoliate orange and Shiikuwasha. IAA concentration of roots was about three times higher in Shiikuwasha than in other rootstocks. GA concentration of trifoliate orange roots was about three times higher than other rootstocks.
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  • Aussanee Paksasorn, Tomoko Hayasaka, Hiroyuki Matsui, Hitoshi Ohara, N ...
    1995 Volume 63 Issue 4 Pages 761-766
    Published: 1995
    Released: May 15, 2008
    The polyamine and ACC contents in mesocarp of Japanese apricot (Prunus mume Sieb. et Zucc.) were determined during fruit development. Polyamine and ACC levels peaked in the early fruit development stage, followed by 'June drop'. Then, polyamine and ACC levels decreased rapidly and changed little until fruit was harvested. The content of spermidine (Spd) in the mesocarp sharply declined during the post-harvest period, but the levels of spermine (Spn) and putrescine (Put), did not change. ACC and ethylene levels peaked 34 days after harvest. Exogenous polyamines, applied to fruit 20 days before normal harvest, delayed fruit drop and ethylene evolution after harvest as compared to the control.
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  • Atsuko Uragarmi, Makoto Nagai, Hiroaki Yoshikawa
    1995 Volume 63 Issue 4 Pages 767-772
    Published: 1995
    Released: May 15, 2008
    Certain characteristics of asparagus cultivars and breeding lines were measured in two trials to test if yield and spear traits might be predictable from early evaluations.
    1. Significant correlation was not observed in both trials between 1) the stalk growth indexes before harvest and accumulated yield for 4 years, and 2) stalk diameter before harvest and average spear weight during the following 4 years.
    2. The subsequent yield potential of cultivars and lines was not predictable from the first-year yield because of its relatively small size ; however, it could be estimated with significant accuracy from the second year's data. 3. The average spear weight and spearhead tightness for the 3 following seasons were predictable from the first year's harvest data.
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  • Kenji Murakami, Manabu Kimura, Sachiko Matsubara
    1995 Volume 63 Issue 4 Pages 773-778
    Published: 1995
    Released: May 15, 2008
    A system of protoplast isolation, callus formation, and plant regeneration in taro (Colocasia esculenta Schott cv. Eguimo) was established.
    1. Friable calli were induced by culturing etiolated stem segments of taro on Murashige and Skoog (MS) medium supplemented with 30g•liter-1 sucrose, 2 mg•liter-1 2, 4-D and 2 mg•liter-1 2ip. Calli were maintained by subculturing on a fresh MS medium.
    2. Protoplasts were easily isolated from suspension cells derived from the friable calli. The component of the enzyme solution for the isolation consisted of 1g•liter-1 Pectolyase Y-23, 5g•liter-1 Cellulase Onozuka RS, 5 mM MES, 5 mM CaCl2•2H2O, and 0.5M mannitol.
    3. Isolated protoplasts were cultured in the liquid media consisting of half strength MS inorganic salts, Kao and Michayluk's (1975) organic substances, various levels of NAA and BA, 0.1M glucose and 0.3M mannitol. Numerous colonies were formed in the medium containing 2mg•liter-1 BA.
    4. Shoot regeneration from protoplast-derived calli occurred on solid MS medium with 0.2mg•liter-1 NAA and 2 mg•liter-1 BA. The shoots initiated roots after being transferred to a MS medium without phytohormones.
    The protoplast culture system established in this study might be useful for cell fusion and electroporation of genes as an approach to breeding of taro.
    Chemical names used: 2-N-MorPholino ethanesulfonic acid (MES) ; 1-naphthanlenacetic acid (NAA) ; 2, 4-dichlorophenoxy acetic acid (2, 4-D) ; N-phenylmethyl-1H-purin-6-amine (BA) ; N-3-methyl-2-butenyl-1H-purin-6-amine (2ip).
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  • Koichi Inoue, Hiroshi Yokota, Katuhiro Makita
    1995 Volume 63 Issue 4 Pages 779-785
    Published: 1995
    Released: May 15, 2008
    The effects of administering 1000 and 2000 ppm sodium ascorbate (NaAs) to roots of lettuce (butter head type) just prior to harvest for 24 hr on the foliar L-ascorbic acid (AsA) content were studied. The results were as follows.
    1. The water absorption ability of the roots was lowered by increasing NaAs concentration such that plants exposed to 2000 ppm withered.
    2. When roots were exposed to 1000 and 2000 ppm NaAs, the AsA contents of the leaves increased 3.5 and 4.7 times over those of the control plants. The AsA content in the lettuce leaves kept at 5°C for 3 days after treatment did not decrease significantly and the appearance of leaves from the treated plants was similar to that of the control.
    3. The K, Ca and Mg contents of leaves from the treated plants were similar to those of the control, which suggests that the mineral content in the leaves was unaffected by the treatment.
    Although the production of lettuce (butter head type) with abundant L-ascorbic acid content was shown to be possible, there are still some problems to be solved before this method can be put into practical use.
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  • Isao Ogiwara, Isao Shimura, Kuni Ishihara
    1995 Volume 63 Issue 4 Pages 787-795
    Published: 1995
    Released: May 15, 2008
    The causes of the development of poorly ripened grains (PRG) at the tip of 'Honey Bantam 36' sweet corn ear based on dry matter production, leaf cutting, shading, and thinning after silk emergence on the development of unfilled grains (UG), were investigated.
    1. Leaf cutting and shading resulted in the increase of PRG, whereas thinning and sparse planting caused it to decrease compared to the control. The occurrence of UG, consisting of PRG and unfertilized grains had a high significant, positive correlation with the occurrence of PRG.
    2. Alteration of the total dry weight by thinning and shading after silk emergence affected the supply of assimilates to ear. Variations in the occurrence of PRG caused by the alteration of the supply of assimilates affected the unfilled tip length and the occurrence of UG.
    3. When plants were grown under the same conditions during the first period (vegetative phase) and later thinned and shaded, the occurrence of UG correlated well with the dry matter accumulation during the grain filling period.
    4. When plants were grown under different conditions during the first period and then placed under the same conditions (equal plant density), the occurrence of UG correlated with dry matter production during the first period. When dry matter production during the first period increased, the partitioning of the dry matter to the ear during the second period increased.
    5. Partitioning of the dry matter within the ear differed significantly between kernals at the tip and at the base. The dry matter within shaded ears was partitioned away from the tip and toward the basal position of the ears as compared to the control.
    6. Dry matter accumulation during grain filling did not differ among treatments whereas the occurrence of UG did. This is attributed to a decreased translocation from stem to ear, especially to the ear tip.
    We conclude that the development of poorly ripened grains is influenced by (i) dry matter accumulation during grain filling, (ii) the amount of dry matter accumulated prior the grain filling, and (iii) the translocation of current photosynthates to the ear, especially to its tip.
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  • Kazuo Ichimura, Masayuki Oda
    1995 Volume 63 Issue 4 Pages 797-803
    Published: 1995
    Released: May 15, 2008
    Effects of extract from wood pulp (wood pulp-made support for plant tissue culture) on the root growth of several vegetables, i. e., cucumber (Cucumis sativus L.), lettuce (Lactuca sativa L.), pea (Pisum sativum L.), radish (Raphanus sativus L.), tomato (Lycopersicon esculentum Mill.), and Welsh onion (Allium fistulosum L.) were examined. Roots of germinated seeds were grown in an extract diluted with water. Root growth of all vegetables except for the pea was stimulated by wood pulp extract. The most sensitive, consistent results were obtained with lettuce, thus it was chosen for further experiments. The pulp extract stimulated root growth much more than did glucose, sucrose, or an inorganic nutrient, suggesting that the root growth stimulating substance (s) are neither sugars nor inorganic ions.
    When pulp extract was fractionated into ethanol soluble and insoluble fractions, the root growth stimulating activity was found in insoluble fraction, indicating that the active substance has high polarity. The ethanol insoluble fraction was further purified by gel filtration using Sephadex G -25 and Bio-Gel P -2 columns. By using Bio-Gel P -2 column, the activity was found in 3 low molecular weight fractions. These results indicate that pulp extract contains at least 3 kinds of root growth-stimulating substances which are highly polar compounds of low molecular weight.
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  • Atsushi Yamasaki, Hiroyuki Miura
    1995 Volume 63 Issue 4 Pages 805-810
    Published: 1995
    Released: May 15, 2008
    The effect of 8, 16, and 24 hr photoperiods for 30, 45, and 60 days at 5 °C on the growth and bolting of Japanese bunching onion (Allium fistulosum L. cv. Kincho and Choetsu) was investigated.
    In both cultivars, 24 hr photoperiod treatment increased plant height and leaf number. Sixteen hr photoperiod increased plant height and leaf sheath diameter only 'Choetsu', but had no effect on the growth of 'Kincho'.
    In the 30 - day treatment, 16% of treated plants bolted under 24 hr, 54% under 16 hr, and 77% under 8 hr in 'Kincho'. When the treatments were longer than 30 days, the percentage of bolting plants increased in the 16 - hr and 24 - hr photoperiods. Thus, in the 60- day treatment, no differences in percentage of bolting were observed among 3 photoperiods. The inhibitory effect of long-day also decreased in 'Choetsu' as the treatment was prolonged; long-day photoperiod delayed bolting and increased the number of leaves until seedstalk formation in both cultivars.
    It was considered that flower initiation of Japanese bunching onion was accelerated by a short-day photoperiod, but the acceleration of flower initiation by short day was reduced when it was sufficiently exposed to low temperature. Therefore, we conclude that Japanese bunching onion requires short-day facultatively in the flower initiation process and the inhibition on the flower initiation by a long photoperiod can be overcome by low temperature.
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  • Masanori Miyazaki, Hiroshi Sato, Masakazu Oku, Takako Goto
    1995 Volume 63 Issue 4 Pages 811-817
    Published: 1995
    Released: May 15, 2008
    The new strawberry cultivar for processing use, 'Benihibari' was selected in 1989 from hybrid seedlings of 'America' and 'Hokowase' at Toyo Institute of Food Technology, Kawanishi, Hyogo.
    The plant form of 'Benihibari' is spreading, and the plant height and the number of leaves are similar to those of 'America'. The harvesting season is from the mid May to the beginning of June, which is earlier than that of 'America'.
    The fruit of 'Benihibari' is conical, bright red, and very glossy. The flesh is shiny scarlet and firm. The soluble solids and acid contents of the fruits are almost the same as those of 'America'. The yield per plant is 579 g which is slightly less than that of 'America'.
    The mature fruits of 'Benihibari' can be detached easily from the calyxes, yielding calyx-free berries. The percentage of calyx-free fruits is much higher than that of 'America'. The torn part of calyx on the fruit is so firm that the fruit does not soften so fast as that of 'America'.
    The fruit of 'Benihibari' is resistant to rot organisms in the feild. The percentage of spoiled fruits is less than 10%, much lower than those of 'America' and 'Hokowase'. The jam made from the fruits of 'Benihibari' is superior to those of 'America' and 'Hokowase'. The preserved fruits are soft, bright red, and flavorful which make 'Benihibari' a good processing strawberry cultivar for open field planting.
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  • Yosuke Tashiro, Tomohiro Oyama, Yoshiyuki Iwamoto, Rumi Noda, Sadami M ...
    1995 Volume 63 Issue 4 Pages 819-824
    Published: 1995
    Released: May 15, 2008
    Previous cytogenetic studies revealed that Allium wakegi Araki has a hybrid origin and its parental plants are A. fistulosum L. and A. cepa L. Aggregatum group. In order to trace the origin of the cytoplasm of A. wakegi and to identify its maternal and paternal plants, restriction fragment length polymorphisms (RFLPs) were studied in the chloroplast DNAs of A. fistulosum, A. cepa Aggregatum group, their reciprocal hybrids and A. wakegi Interspecific RFLPs were clearly observed between A. fistulosum and A. cepa Aggregatum group with four restriction enyzmes, Sma I, Pvu II, Xho I and Bgl II. The reciprocal interspecific hybrids showed the restriction patterns similar to those of the maternal plants. All the clones of A. wakegi, collected from Japan, Korea, China, Taiwan and Myanmar, showed restriction patterns quite similar to those of A. fistulosum without exception. These results establish that the maternal and paternal plants of A. wakegi are A. fistulosum and A. cepa Aggregatum group, respectively.
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  • Keiichi Okazaki, Joichi Kawada, Masaaki Kunishige, Kinji Murakami
    1995 Volume 63 Issue 4 Pages 825-833
    Published: 1995
    Released: May 15, 2008
    To increase the variation of flower size of Lilium × 'Asiatic Hybrids', L. × 'Asiatic Hybrids', L. dauricum were reciprocally crossed with L. concolor. The hybrid progenies were forced into bloom to check the characteristics for cut flower production.
    1. No seed set in the cross of L. concolor × L. × 'Asiatic Hybrids' by normal and cutstyle pollination.
    2. In the reciprocal cross, hybrids were obtained by using cut-style pollination and embryo culture. The ovary set rate was 100%, but the endosperm was lacking or it developed slightly into a watery mass. When the emryos were 1 to 6 mm long, they became callus-like and distorted. The average number of embryos per ovary was 5.1 and ranged from 0.5 to 21 in 26 cross combinations. The hybrid seeds did not germinate in vermiculite.
    3. In the cross between L. dauricum × L. concolor, the length of embryos ranged from 4 to 6 mm when they became distorted. They appeared normal compared to progenies between L. × 'Asiatic Hybrids' × L. concolor. The hybrids-seeds also did not germinate in vermiculite.
    4. The survival rate in embryo culture varied among the crosses but averaged 47.4%.
    5. Although the average pollen fertility rate among 11 hybrids was 72.9%, the effort to backcross the hybrid with their parents met with limited success. Hybrids produced many seeds when backcrossed with L. concolor, but a few seeds were obtained from L. ×'Asiatic Hybrids'. When the parents were pollinated with hybrid pollen, 'Asiatic Hybrids' produced many seeds, but L. concolor produced no seed. About the half of the seeds obtained from backcrosses were abnormal and only 20.3 to 34.0% germinated in vermiculite. When immature embryos were excised and cultured, the survival rate was increased above 73.6%.
    6. Flowers and leaves of hybrids were intermediate between their parents; the hybrids grew vigorously, having longer stems, more flowers per inflorescence than thier parents. Hybrids were similar to L. concolor rather than L. × 'Asiatic Hybrids' because of their relatively small flowers and slender leaves.
    7. The number of days to flowering was about 90 when hybrids were forced in winter, and about 65 when they were cultured after the bulbs were harvested and stored at -2 °C in autumn. The hybrids were evaluated for their cut flower production and the more promising progenies were selected to serve as mother plants for further breeding.
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  • Yoshihiko Koyama, Akira Uda, Osamu Wada, Morihiro Fujino
    1995 Volume 63 Issue 4 Pages 835-842
    Published: 1995
    Released: May 15, 2008
    To supply high quality cut carnation flowers in summer, budded shoots harvested on replanting time (from mid-May to early June) were pre-conditioned with silver thiosulphate (STS) and/or sucrose and stored at 1 °C for 12 weeks. The effects of pre-conditioning on the opening, vase life, and sugar contents were investigated.
    1. The vase life of 'Nora' and 'Coral' carnation flowers pre-conditioned with STS was extended after the 12 weeks of cold storage, but vase life of 'Coral' treated with STS +sucrose was slightly shortened because less preservative solution was absorbed.
    2. The sugar concentration in petals of 'Nora' was maintained at a certain level by sugars translocated from leaves during 12-week storage. After cold storage, petals of shoots pre-conditioned with 0.3 mM STS + 10% sucrose had the highest sugar concentration but no promotive effect on vase life was observed.
    The results confirm that high grade cut carnation flowers can be obtained in mid-summer by pre-treating budded shoots with STS and cold storing them at 1 °C for 12 weeks.
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  • Yoshiji Niimi
    1995 Volume 63 Issue 4 Pages 843-852
    Published: 1995
    Released: May 15, 2008
    Lilium japonicum growing in the experimental field were collected in early May and segments of their scales, leaves and stems of the plants were cultured in vitro on a basal medium consisting of Murashige and Skoog's inorganic salts (1962) supplemented with several organic nutrients. Young leaf-segments were a suitable source for propagation, because they were least contaminated and almost had the same capacity as scale seg- ments for bulblet regeneration. Bulblets were proliferated by culturing whole scales or segments on the basal medium supplemented with 0.1 mg•lliter-1 NAA and 0.01 mg•lliter-1 BA. A cold treatment at 4 °C for more than 12 weeks broke the dormancy of in vitro cultured bulblets. In vitro light conditoin affected both post-in vitro bulblet-rot infection and plant growth in soil. The bulblets incubated in the dark were more sus- ceptible to soil-born organisms than were those incubated in the light. Nearly all the bulblets of more than 400 mg in weight grew into plants with elongated axes (epigeous type plant; ETP). The ETP plantlets required at least 2 years' cultivation before they flowered.
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  • Kenjiro Toki, Nobuyuki Katsuyama
    1995 Volume 63 Issue 4 Pages 853-861
    Published: 1995
    Released: May 15, 2008
    1. To understand the mechanism of flower colour variations from red to purple in crape myrtle cultivars, absorption spectra and Hunter's L, a, b values of intact petals were measured. In this study 67 cyanic plants were classified into two groups : red group, λmax' 524544 nm; b/a, (- 0.183) (+0.165) : purple group, λmax, 555 570 nm; b/a, (-0.785) (-0.442). Relatively strong absorption about 360 nm was recognized in purple flowers, and high negative correlation (r = -0.897***) was obtained between b/a and E360/EVIS max.
    2. Three anthocyanins from the red and purple flowers were isolated, analysed chromatographically and spectrally, and their ratios determined.
    All 67 plants contained the 3-glucosides of delphinidin, petunidin, and malvidin as the major anthocyanins. The ratios among these anthocyanins varied widely, but had no correlation to Hue values (b/a), except that in the red group there was a negative correlation between b/a and the relative malvidin 3-glucoside concentration, and a positive one between b/a and relative delphinidin 3-glucoside conc.
    3. The pH values measured by tightly pressing the petals to a flat electrode varied from 4.2 to 5.1, but there was no correlation between these values and flower colour. 4. Crude aqueous extracts from the red and purple flowers were partitioned with ethyl acetate and the organic fraction was concentrated; the aqueous fraction was dissolved in a buffer solution. Visible absorption maxima shifted bathochromically when the above two fractions from red and purple flowers were combined.
    5. Ellagic acid derivatives detected in the purple flowers are assumed to be the main agents for the blueing of the 'flowers in crape myrtle.
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  • Nyoyen J. L. Roxas, Yosuke Tashiro, Sadami Miyazaki, Shiro Isshiki, Ak ...
    1995 Volume 63 Issue 4 Pages 863-870
    Published: 1995
    Released: May 15, 2008
    In order to establish a method for the preservation of Higo chrysanthemum cultivars (Dendranthema × grandiflorum (Ramat.) Kitam.), studies were conducted on the influences of the type of explant, temperature, light and other conditions on the survival and growth of cultures in vitro.
    Cultures at 5 °C, 15 °C, 25 °C and 25°-15°-5 °C had maximum rates of 100%, 60%, 53% and 100% of survival, respectively, for a period of 12 months. Cultures at 15 °C and 25 °C showed a comparatively active growth and advanced senescence or withering after 12 months of incubation. On the other hand, cultures at 5 °C and 25°-15°-5°C showed growth retardation and delayed senescence which had maximum rates of 100% and 75% survival, respectively after 24 months. Dark condition increased the survival rate of cultures at 5 °C although the plant height was comparatively smaller than that under light. Nodal segments showed higher survival rate than the apical buds, and the removal of the expanded leaf on the explant showed advantages upon incubation. One ml of MS medium without growth regulators in a 12 × 75 mm test tube was enough to ensure the survival of a culture at 5 °C for a period of 24 months without transferring to a new medium or without supplementing the medium.
    Based on the above results, a practically safe, economical and useful system for the in vitro preservation of Higo chrysanthemum has been established. This is presently applied to the 21 cultivars.
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  • Hiroto Yoshioka, Yoshioki Kashimura, Katsuyoshi Kaneko
    1995 Volume 63 Issue 4 Pages 871-878
    Published: 1995
    Released: May 15, 2008
    Four β-D-galactosidases (GA-ase I, II, III, and IV) and one α-L-arabinofuranosidase (AF-ase) activities were detected in cell wall extracts from apples (Mains dornestica Borkh. cv. Starking Delicious) stored at 0°C for five months.
    The GA-ase fractions separated by hydroxylapatite column chromatography degraded a polyuronide prepared from apple cell walls, releasing galactose. GA-ase II, III, and IV fractions contained arabinogalactan degrading and galactose releasing activities, but GA- ase I failed to degrade arabinogalactan. AF-ase fraction degraded polyuronide and arabinogalactan releasing arabinose and other sugars.
    The activities of GA-ase II, III and IV decreased gradually as the apples softened in storage. The activities of GA-ase I and AF-ase which were not detectable at harvest, appeared and increased during storage.
    These galactose and arabinose releasing activities, may be involved in the degradation and solubilization of polyuronide, araban, and galactan in the cell walls of apples during softening.
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  • Yasunori Hamauzu, Kazuo Chachin
    1995 Volume 63 Issue 4 Pages 879-886
    Published: 1995
    Released: May 15, 2008
    Mature green tomato fruits were initially stored at 20°, 30° and 35 °C and then transferred to other temperatures at various times within a 25-day storage period.
    1. Fruits transferred from 20 °C to 30 °C (20°→30 °C) or from 20 °C to 35 °C (25°→35 °C) developed less color depth and contents of phytoene and lycopene than did those retained at 20 °C, but carotene contents increased temporarily in the 20°→30 °C treatment. Conversely, fruit transferred from 30 °C to 20 °C (30°→20 °C) or from 35 °C to 20 °C (35°→20 °C) progressively became redder.
    2. Ratio of lycopene precursors, phytoene, phytofluene and ζ-carotene to total carotenes was highest in tomatoes kept at 20 °C. In the 30°→20 °C or 35°→20 °C treatments, total carotene contents became almost the same as those kept at 20 °C, but the ratio of the precursors to total carotenes became smaller while that of lycopene to total carotenes increased.
    3. Tomatoes at 30 °C, β-carotene content and level of cis-isomer increased, but those in the 20 °→30 °C treatment, the β-carotene remained constant.
    4. α-Tocopherol content increased in tomatoes kept at 30 °C and 35 °C, whereas it did not increase significantly at 20 °C; it increased after the tomatoes were transferred from 30° to 20 °C or from 35° to 20 °C.
    The data indicated that the rates of synthesis of lycopene, β-carotene and α-tocopherol differ according to temperature. The effect of high temperature or treatment with changing temperature on each pathway may be explained by changes in metabolism of precursors of both carotenoid and tocopherol.
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