Journal of the Japanese Society for Horticultural Science
Online ISSN : 1880-358X
Print ISSN : 0013-7626
ISSN-L : 0013-7626
Volume 70 , Issue 3
Showing 1-20 articles out of 20 articles from the selected issue
  • Takuya Tetsumura, Ryutaro Tao, Akira Sugiura
    2001 Volume 70 Issue 3 Pages 275-280
    Published: May 15, 2001
    Released: January 31, 2008
    JOURNALS FREE ACCESS
    The factors influencing rooting of softwood cuttings of two cultivars, 'Jiro' and 'Nishimurawase', of Japanese persimmon (Diospyros kaki Thunb.) were studied. The cuttings from the root suckers of micropropagated trees rooted best, followed by those from the shoots of micropropagated trees and grafted trees in that order. Except for the cuttings from grafted trees, the shorter the cuttings, the higher the rooting percentage. When planted in late June, the single bud, leafy cuttings (leaf-bud cuttings) taken from the root suckers and treated with indole-3-butyric acid (IBA), 70% or more rooted well. When planted in late July or late August, however, less than 40% of the leaf-bud cuttings rooted. Comparable cuttings without IBA treatment scarcely rooted when planted in late June, and did not root at all when planted in late July or late August. There was no significant difference in the rooting capacity between the two cultivars. Almost all leaf-bud cuttings from the root suckers survived during the experimental period (60 days), although those from the shoots of grafted trees died gradually ; none of the 25-cm cuttings from the root suckers survived 25 days after planting. The vascular cambium at the base of leaf-bud cuttings from the root suckers began to divide actively soon after planting. Callus formed in the phloem and cortex of the cut surface and developed extensively. However, active cell division was not observed at the bases of leaf-bud cuttings from the shoots of grafted trees nor 25-cm cuttings from the root suckers. Initial cells of the adventitious root produced in the vascular cambium of the leaf-bud cuttings from the root suckers were first observed 20 days after planting ; they developed to roots and emerged 30 days after planting.
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  • Katsuhiro Shiratake, Yoshihiro Kobae, Yasuo Suzuki, Makoto Nakaune, Ko ...
    2001 Volume 70 Issue 3 Pages 281-286
    Published: May 15, 2001
    Released: January 31, 2008
    JOURNALS FREE ACCESS
    Cloning a cDNA encoding tonoplast water channel of pear fruit disclosed that its deduced amino acid sequence has 77%, 52%, and 50% identities to γ tonoplast intrinsic protein (TIP), δ TIP, and α TIP of Arabidopsis, respectively. Therefore, this clone is considered to be a member of γ TIPs and is designated as "Py-γ TIP". Deduced amino acid sequence of Py-γ TIP has six membrane spanning domains and two NPA motifs, which are conserved within all water channels. Antibody against VM23, which is the vacuolar water channel of radish, recognized two proteins derived from tonoplast proteins of pear fruit yielded a major spot at pI 4.8 and a minor one at pI 5.2 by two dimensional-polyacrylamide gel electrophoresis (2D-PAGE). Putative pI of deduced amino acid sequence of Py-γ TIP is 4.86 ; therefore, the major spot in 2D-PAGE is considered to be a translated product from Py-γ TIP which might play a dominant role in fruit. Northern blot analysis showed that Py-γ TIP was expressed especially high at 23 and 41 days after flowering (DAF), which correspond to the middle and end of the cell-division stage of fruit development. This suggests that the role of Py-γ TIP might be to sustain vacuole biogenesis and to prepare the cells for the rapid increase in vacuolar volume at the cell-division stage of a fruit.
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  • Katsuhiro Shiratake, Haruka Goto, Masayoshi Maeshima, Shohei Yamaki
    2001 Volume 70 Issue 3 Pages 287-293
    Published: May 15, 2001
    Released: January 31, 2008
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    Fluctuations of the protein levels of H+-pumps and water channels of tonoplast and plasma membrane were determined by immunoblot analysis during grape berry development. The growth pattern of a grape berry follows a double sigmoid curve during which many physiological changes are considered to occur, especially after veraison. However, the protein levels of H+-pumps and water channels, except V-ATPase, did not change after veraison. The level of V-ATPase, one of the tonoplast H+-pumps, was relatively high at 42 days after flowering (DAF) and after veraison. The level of V-PPase, another tonoplast H+-pump, changed more gradually than did that of V-ATPase. Two bands of plasma membrane H+-pump (P-ATPase) were detected ; the level of each band changed differently. However, the change in total P-ATPase level was relatively small during berry development. Changes in the level of water channels of tonoplast and plasma membrane, that is, VM23G and PAQ, respectively, were similar. That is, their levels, which were lowest at 30 DAF, increased dramatically at 42 DAF, and thereafter remained nearly constant. In VM23G, the level increased 121 DAF. A previous study in pear fruit suggested that a relationship exists between tonoplast water channel and cell expansion, but such a relationship did not exist in the grape berry. Both in the pear fruit and in grape berry, V-ATPase level nearly paralleled that of the growth rate.
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  • Hidekazu Sasaki, Kazuo Ichimura, Shigeo Imada, Masayuki Oda
    2001 Volume 70 Issue 3 Pages 294-298
    Published: May 15, 2001
    Released: January 31, 2008
    JOURNALS FREE ACCESS
    Cabbage seedlings cold-acclimated for 8 days at 5°C were transferred to 15, 20 or 25°C in the dark or light. The acquired freezing tolerance was reversed during deacclimation at all temperatures ; the higher the deacclimation temperature, the more accelerated was the loss of freezing tolerance. Concentrations of soluble sugars, particularly sucrose in the leaves, rapidly decreased within deacclimation for 1 to 3 hr at 20°C in the dark. This reduction was accompanied with a decrease in the freezing tolerance of leaves. Activities of soluble acid invertase in leaves were not affected by short-term deacclimation.
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  • Yasuyoshi Hayata, Xin Xian Li, Yutaka Osajima
    2001 Volume 70 Issue 3 Pages 299-303
    Published: May 15, 2001
    Released: January 31, 2008
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    We compared the growth and invertase activity of pollinated melon (Cucumis melo L.) fruit and parthenocarpic fruit induced by CPPU [1-(2-chloro-4-pyridyl)-3-phenylurea]. CPPU-treated fruit enlarged from anthesis until the 15th day after anthesis (DAA). However, the growth of parthenocarpic fruit was slower than that of pollinated fruit during the later growth stage. Non-pollinated flowers without the CPPU treatment did not grow ; they wilted within 7 DAA. Acid invertase (AI) and neutral invertase (NI) activities in the ovary rapidly decreased from 0 to 5 DAA, whereas, AI activity in the mesocarp of pollinated and/or CPPU-treated fruit dramatically increased to 5 DAA, it declined as fruit matured. AI activity in CPPU-treated fruit was higher than that of pollinated fruit without the CPPU treatment during the early stage ; but between 25 and 40 DAA, the activity in CPPU-treated non-pollinated fruit was lower than that in the pollinated ones. NI activity was lower than AI activity in the mesocarp in all plots throughout fruit development. The seasonal patterns in NI activity were similar to those of AI activity. There was a close relationship between the growth rate and invertase activity in melon fruit. CPPU noticeably stimulated those activities in mesocarp tissues at anthesis and shortly thereafter.
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  • Yasunori Yoshida, Harumi Takahashi, Hiroomi Kanda, Koki Kanahama
    2001 Volume 70 Issue 3 Pages 304-309
    Published: May 15, 2001
    Released: January 31, 2008
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    The interaction between photoperiods and plant growth regulators [gibberellin A3 100ppm (GA), uniconazole P 25ppm (Uni), n-propyl dihydro-jasmonate 50ppm (PDJ), and salicylic acid 1000ppm (SA)] on the development of the main shoots, spikes, and aerial and new tubers in Chinese yam (Dioscorea opposita Thunb. cv. Ichoimo) plants was observed. The untreated control plants yielded the longest main shoots followed by GA, SA, PDJ, and Uni. Plant, treated with growth regulators, grew more under a 24-hr photoperiod than did those under an 8-hr photoperiod. GA treated plants, grown under the 24-hr photoperiod, developed spikes at a significantly lower node than that similarly treated plants grown under an 8-hr photoperiod ; whereas the first flowering node on the control, GA, SA, Uni, and PDJ treated plants, grown under the 24-hr photoperiod, was equally higher than comparable plants, grown under the 8-hr photoperiod. More spikes per plants were initiated under the 24-hr photoperiod than on plants grown under an 8-hr photoperiod. GA treatment severely decreased the number of spikes under the 8-hr photoperiod. Aerial and new tubers developed earlier on plants under the short day than did those under constant light, but the new tubers on the latter treatment weighted more than did those on the former. The formation of aerial tubers was severely inhibited by GA but promoted by Uni under both photoperiods, while the growth of new tubers was significantly promoted by GA and significantly inhibited by Uni. PDJ and SA had no effect on the growth of aerial and new tubers.
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  • Katsuhiko Inamoto, Sumiya Sakoda, Takanori Hase, Kenzo Katsukawa, Mits ...
    2001 Volume 70 Issue 3 Pages 310-314
    Published: May 15, 2001
    Released: January 31, 2008
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    A previously developed dynamic growth simulation model for cut tulip production in a plant factory system which predicts forcing period and flower quality of cut tulips from duration of bulb chilling and forcing temperature was confirmed. In a 1993-1994 experiment in which bulbs were forced at 20°C, irrespective of the duration of their chilling period at 2°C, the simulated values of number of days from planting to anthesis, shoot (cut flower) fresh weight, perianth length and dry weight of the component parts at anthesis correlated well with the observed values. In a 1998-1999 experiment in which the forcing temperature was lowered with the extension of the duration of bulb chilling at 2°C, when the duration of bulb chilling was extended to 26 weeks or longer, shoot fresh weight, perianth length and dry weights of shoot and floral organs at anthesis were underestimated by the model, while the dry weight of daughter bulbs was overestimated. These differences were supposed to be caused by fluctuation in bulb properties and could be diminished by inputting the dry weights of the mother bulb and daughter bulbs at planting into the model.
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  • Masami Mato, Takashi Onozaki, Yoshihiro Ozeki, Daisuke Higeta, Yoshio ...
    2001 Volume 70 Issue 3 Pages 315-319
    Published: May 15, 2001
    Released: January 31, 2008
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    Analyses for anthocyanin concentration and flavonoid composition of flowers of two white, four light-pink, four deep-pink, and three red cultivars derived from 'William Sim' carnation revealed that anthocyanin content increased from the light-pink-flowered cultivars, to the deep-pink-flowered cultivars, and to the red-flowered cultivars. Simultaneously, examination of gene expression of enzymes involved in anthocyanin biosynthesis showed that transcriptional levels of dihydroflavonol 4-reductase gene (DFR) and anthocyanidin synthase gene (ANS) in the deep-pink-flowered cultivars were correspondingly lower in the red-flowered cultivars, whereas those of ANS was much lower in the light-pink-flowered cultivars except in 'Lolyta'. In light-pink-flowered cultivars, transcripts of flavanone 3-hydroxylase gene (F3H) in 'Lolyta' and ANS in 'Dusty' were undetectable on the Northern blots, but both transcripts were detected on reverse transcription-polymerase chain reaction (RT-PCR). Low anthocyanin accumulation in pink-flowered cultivars seems to be regulated at different steps in anthocyanin biosynthesis.
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  • Akira Kitajima, Yoshiki Okada, Kojiro Hasegawa
    2001 Volume 70 Issue 3 Pages 320-327
    Published: May 15, 2001
    Released: January 31, 2008
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    'Muroto-Konatsu' and 'Nishiuchi-Konatsu' are seedless bud mutants of Hyuganatsu (Citrus tamurana) which were examined for their bases of seedlessness. 1. There were no significant differences in the numbers of ovules and locules per ovary among 'Muroto-Konatsu', 'Nishiuchi-Konatsu' and common type Hyuganatsu. 2. When 'Muroto-Konatsu', 'Nishiuchi-Konatsu' and the common type were pollinated with pollen from 'Suisho-Buntan' pummelo, the pollen tubes barely penetrated the pistil of 'Muroto-Konatsu', whereas they grew down to the ovary of 'Nishiuchi-Konatsu' and the common type. Hence, 'Muroto-Konatsu' had a few fertilized ovules which failed to set seeds, whereas 'Nishiuchi-Konatsu' and the common type had the same number of pollen tubes in the upper part of their ovaries 14 day after pollination and set an equal of fertilized ovules and seeds. 3. Self-pollination and reciprocal pollination were performed in 'Nishiuchi-Konatsu' and the common type. In self-pollinated 'Nishiuchi-Konatsu', the pollen tubes penetrated into upper part of the ovary. Hence, a few fertilized ovules were produced. In reciprocal pollinated 'Nishiuchi-Konatsu' and the common type and self-pollinated the common type, the pollen tubes penetrated only into middle part of the styles. Hence no fertilized ovules were produced. These data indicate that the seedlessness of 'Muroto-Konatsu' results from the inhibition of pollen tube growth into the pistil when cross-pollinated, whereas in 'Nishiuchi-Konatsu', which is partially self-compatible, it is nearly always seedless because of poor pollen growth when self-pollinated. We conclude that seedless cultivars 'Muroto-Konatsu' and 'Nishiuchi-Konatsu' mutated in the characters of the pistils on cross-compatible and self-incompatible, respectively.
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  • S. Hiratsuka, M. Nakashima, A. Yagami, Y. Kowyama, Y. Kawai
    2001 Volume 70 Issue 3 Pages 328-332
    Published: May 15, 2001
    Released: January 31, 2008
    JOURNALS FREE ACCESS
    Self-incompatibility genotypes (S-genotype) were reexamined in the Japanese pear 'Choju', 'Kimizukawase', 'Meigetsu', and 'Ichiharawase'. The S-genotypes of the former 2 cultivars are designated as S2S5, whereas those of the latter 2 cultivars are S1S5. 'Choju' and 'Kimizukawase', which are cross-incompatible in both directions, possessed the S1- and S5-allele associated proteins (S-protein) in their styles. PCR (polymerase chain reaction) amplifications of self-incompatibility genes (S-gene) also revealed the presence of S1- and S5-gene fragments in both cultivars. Thus, the S-genotypes of 'Choju' and 'Kimizukawase' were confirmed to be S1S5, but not S2S5. 'Meigetsu' and 'Ichiharawase' were compatible with 'Choju' ; their styles contained the S1-protein but not the S5-protein. PCR amplification also suggested the absence of S5-gene in both cultivars. These results together with those in the literature on the appearance of F1 individuals with pollen cross-incompatibility with 'Meigetsu' indicate that the S-genotypes of 'Meigetsu' and 'Ichiharawase' are S1S7 or S1Sx (Sx indicates an allele other than S1 to S7).
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  • Sojiro Chikaizumi
    2001 Volume 70 Issue 3 Pages 333-340
    Published: May 15, 2001
    Released: January 31, 2008
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    The effects of storage temperature and polyethylene bagging on the occurrence of "Kohansho", a physiological disorder of Hassaku (Citrus hassaku hort. ex Tanaka) fruit were investigated. After a postharvest storage at 5°C for a period, the fruit were transferred to a rooms held at 10, 15, 20, 25, 30 and 35°C. Subsequently, they were evaluated for the occurrence of "Kohansho." The fruit kept at 5°C and at 35°C, the disorder did not appear, but kept at between 15 to 25°C numerous fruit came down with the disorder. The "Kohansho" disorder appeared earlier at 25°C than at 15°C. The disorder manifested itself 24 to 48 hr after fruit were transferred from 5 to 20°C, but the symptoms were not observed between 48 to 96 hr. Placing fruit in a polyethylene bag reduced seriousness of the disorder, especially, if done immediately after the harvest. When fruit stored at 20°C were taken out of the polyethylene bag, symptoms of the disorder appeared after 5 hr, but the fruit remained sound if kept in the bag for 32 hr at 20°C. The appearance of "Kohansho" symptoms is attributed to the increase in CO2 concentration in a polyethylene bag to a maximum level during storage at 5°C. In bagged fruit, the respiration which accumulate CO2 in the fruit tissue, such as flavedo or in the stomatal cavity, eventually emerge, increasing the CO2 concentration within the bag. Concurrently, the relative humidity within the bag increased from 30% to above 90%. Fruit weight decreased slightly accompanied by a reduction in abscisic acid (ABA) content in the peel. The number of stomata per fruit was estimated to be 800, 000 ; microscopic examination revealed that the stomata in the affected area remained open.
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  • Takayoshi Ohara, Akio Kojima, Tadayuki Wako, Denji Ishiuchi
    2001 Volume 70 Issue 3 Pages 341-345
    Published: May 15, 2001
    Released: January 31, 2008
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    The suppressed branching trait in melon is a labor saving characteristic because it eliminates the need to prune lateral shoots. The mode of inheritance of this suppressed branching trait, derived from Cucumis melo var. agrestis and introduced into 'Melon Ano No.17', was investigated. Segregation of branching types in F1, its reciprocal cross F2 and backcross progenies from the cross between 'Melon Ano No.17' and 'Harukei-3', a normal branching variety, fits the expected ratio assuming that the trait is controlled by a single recessive nuclear gene. Contrarily, F1 progenies between 'Melon Ano No.17' and 'YS-Honeydew', another normal branching variety, exhibited a continuous variation from the suppressed branching type to the normal branching type. These results suggest that the suppressed branching trait is controlled by a single recessive or incompletely dominant major gene, which we call suppressed branch (symbolized by sb), and that the degree of dominance may greatly be affected by the genetic background and/or environmental factors. When the relationship between suppressed branching trait and some other characters in the F2 progenies of 'Melon Ano No.17' and 'Harukei-3' were examined, the suppressed branching trait correlated negatively with plant vigor.
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  • Eiji Nishihara, Kuniaki Takahashi, Noboru Nakata, Kiyoshi Tanaka, Keit ...
    2001 Volume 70 Issue 3 Pages 346-352
    Published: May 15, 2001
    Released: January 31, 2008
    JOURNALS FREE ACCESS
    The effects of 5-aminolevulinic acid (ALA), a key precursor in the biosynthesis of porphyrins, in a low level (0, 0.18, 0.60 or 1.80mM) on the photosynthetic rate, hydrogen peroxide contents, antioxidant substrates, and active oxygen-scavenging enzymes were investigated in the 3rd leaves of spinach (Spinacia oleracea). 1. Photosynthetic rates of leaves that were treated with different concentrations of ALA, increased significantly in day 3, and remained so for 6 days. 2. Hydrogen peroxide (H2O2) contents in leaves increased from day 6 to 9. The increase seems to be correlated with the promotion of the photosynthetic rate. 3. Oxidized ascorbate (DHA)/reduced ascorbate (ASC) ratio in treated leaves tended to remain constant, whereas reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio increased. 4. Catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR) activities increased by day 3 after the ALA treatment. Superoxide dismutase (SOD) activity did not vary after ALA treatment.
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  • Hiroko Yamazaki, Takaaki Nishijima, Masaji Koshioka, Hiroyuki Miura
    2001 Volume 70 Issue 3 Pages 353-359
    Published: May 15, 2001
    Released: January 31, 2008
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    Changes in carbohydrate concentrations in basal leaf sheaths (this part corresponds to a bulb after bulb development) of two Allium × wakegi Araki cultivars, 'Kiharabansei No.1'(dormant type) and 'Ginoza'(nondormant type) during bulb development and postharvest storage were investigated. There was little difference in the fructose, glucose, sucrose, and fructans concentrations throughout the experimental period between 'Kiharabansei No.1' and 'Ginoza'. Hence, only changes in the former are discussed. During bulb development, when plants of 'Kiharabansei No.1' became dormant, the concentrations of fructose and glucose decreased, while those of fructans and total carbohydrates increased ; there were no significant changes in sucrose concentrations. During postharvest storage of 'Kiharabansei No.1' bulbs, they were gradually released from dormancy and the concentrations of all the components remained constant. The percentage of fructans to total carbohydrates after bulb development exceeded 90% (w/w). This accumulation of fructans was specific to basal leaf sheaths. When bulbs of 'Kiharabansei No.1' planted in moist vermiculite began to sprout, the concentrations of fructose and glucose in the bulbs increased, while those of fructans and total carbohydrates decreased.
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  • Jincai Li, Shuichiro Matsui
    2001 Volume 70 Issue 3 Pages 360-365
    Published: May 15, 2001
    Released: January 31, 2008
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    Three foliar scavenging enzymes of reactive oxygen species : superoxide dismutase (SOD), ascorbate peroxidase (APX) and catalase (CAT) in the CAM plant, Sophrolaeliocattleya Estella Jewel 'Kazumura' have low activities in comparison to those of a C3 plant, Cymbidium Sazanami 'Harunoumi'. The former underwent changes during chilling and cold-night acclimation which differed from those of the latter. 1. During exposure to 4°C for 24 hr in the dark, Cattleya leaves had lower SOD activities than had non-chilled leaves kept at 28°C, whereas their APX and CAT activities were higher. In chilled Cymbidium leaves, SOD and APX activities were significantly higher, whereas CAT was just slightly above those of non-chilled leaves. 2. In Cattleya leaves chilled for 8hr at 4°C for 10 days at night, SOD activities increased for 6 days and remained so until the last day, while APX activities increased for the last day. CAT activities increased for 2 days and then decreased gradually. In Cymbidium leaves, the SOD activity increased for 6 days, followed by a decrease ; APX activity, increased for 4 days, and subsequently remained at that level ; CAT activities increased for 2 to 4 days and then decreased sharply to a level below that of the non-chilled leaves. 3. Cold-night acclimation at 5°C for 40 days showed no significant changes in SOD activity between acclimated and non-acclimated leaves in both Cattleya and Cymbidium plants. APX activity in Cattleya increased gradually until the 30th day and that of Cymbidium increased for 20 days and then ceased increasing. CAT activity in Cattleya leaves was consistently and slightly higher during the acclimation period, while in the Cymbidium, it decreased for 20 days and, thereafter, recovered slightly.
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  • Ikuo Miyajima, Yukio Ozaki, Misuzu Itateyama, Ryohei Ikematsu, Hiroshi ...
    2001 Volume 70 Issue 3 Pages 366-371
    Published: May 15, 2001
    Released: January 31, 2008
    JOURNALS FREE ACCESS
    The genetic identity of old Camellia 'Uraku' trees, growing in various locations in Japan, was assessed by RAPD analysis. Four camellia varieties and two seedlings of 'Uraku' were easily distinguishable from 'Uraku' by RAPD analysis, using 51 of 12-mer arbitrary primers. Genetic monomorphism was recognized among the seven lines of old 'Uraku' trees and 'Koshikibu' which was growing at Chofukuji Temple in Kyoto. Seemingly, these old 'Uraku' trees and 'Koshikibu' are clonal strains which proliferated more than 400 years ago by vegetative propagation.
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  • Jincai Li, Xiheng Zhao, Shuichiro Matsui
    2001 Volume 70 Issue 3 Pages 372-379
    Published: May 15, 2001
    Released: January 31, 2008
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    Sophrolaeliocattleya Estella Jewel (Cattleya) and Cymbidium Sazanami plants grown in a shaded greenhouse, kept between 18 and 28°C, were exposed to full sunlight (FS, 0.61kW·m-2) on 21st October, whereas others were grown under 70% (high radiant flux), 40% (control) and 10% (low radiant flux) full sunlight from May to October. 1. Activities of foliar antioxidative enzymes, superoxide dismutase (SOD), ascorbate peroxidase (APX) and catalase (CAT), were much more in a CAM plant, Cattleya than in a C3 plant, Cymbidium ; those enzyme activities increased slightly in the daytime in the former and at the beginning of night in the latter. FS reduced SOD activity but greatly enhanced CAT activity and slightly promoted APX activity in Cattleya leaves, whereas the same radiant flux on Cymbidium leaves resulted in a big decreased in SOD and CAT activities and a slight one in APX activity. The decrease is attributed to light stress. 2. One month after the onset of the shading treatment, SOD and CAT activities in Cattleya leaves at the high radiant flux decreased significantly compared with those of the control and remained at low levels ; CAT activity, however, recovered slightly with further cultivation. In Cymbidium leaves under a high radiant flux, SOD, APX and CAT activities decreased for three months from the onset and of the experiment. At the low radiant flux, APX and CAT activities in Cattleya and Cymbidium leaves increased and sustained their high activities during further cultivation with the exception of SOD of Cattleya. 3. Foliar chlorophyll contents in both orchid hybrids decreased with an increasing radiant flux, yielding high positive correlations to those three enzyme activities. Ratios of chlorophyll a to chlorophyll b and β-carotene contents in leaves of Cattleya plants grown at the high radiant flux were markedly low after one month from the onset of shading, but they increased to the same levels as the control after 3 months. In Cymbidium leaves, the ratios and β-carotene contents decreased slightly at the high radiant flux, while at the low radiant flux, both chlorophyll and β-carotene contents increased greatly. Thus, Cattleya plants have a greater potential to adapt to high radiant fluxes than do Cymbidium plants, although these two orchids hybrids do not easily acclimatize to high radiant radiant fluxes but they do readily to low fluxes.
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  • Toshihiko Sugiura, Haruyuki Kuroda, Daiyu Ito, Hitoshi Honjo
    2001 Volume 70 Issue 3 Pages 380-384
    Published: May 15, 2001
    Released: January 31, 2008
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    We investigated correlations between specific gravity and soluble solids concentration in grape berries, since the nondestructive measurement of soluble solids concentration by near infrared spectroscopy is not put to practical use. Specific gravity of each cluster was measured by using an electronic balance and an acoustic volume meter that can measure volume without dipping fruits in water. Soluble solids concentration (Brix) of all berries in each cluster was measured using a refractometer. The relationship between specific gravity and Brix value of clusters of 'Kyoho' grape was constant and a linear one, regardless of the harvest year and the production district. The relation had a high correlation (r=0.981***) within 16-23° Brix with a standard error of 0.35° Brix. High correlations were also found between specific gravity and Brix value in clusters of 'Campbell Early', 'Neo Muscat' and 'Koshu' grape. The slope of the regression line varied little among the four varieties. These results suggest that the measurement of specific gravity with an acoustic volume meter is a useful method to measure nondestructively the soluble solids concentration of clusters.
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  • Ryohei Nakano, Shinji Harima, Yasutaka Kubo, Akitsugu Inaba
    2001 Volume 70 Issue 3 Pages 385-392
    Published: May 15, 2001
    Released: January 31, 2008
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    'Tonewase' is an early maturity strain selected from 'Hiratanenashi', an astringent Japanese persimmon cultivar. In some districts of Japan, 'Tonewase' has been grown under forcing-culture conditions, which often results in rapid softening during postharvest distribution. In this study, we elucidated that this softening is caused by water-stress-induced ethylene that can be suppressed by reducing water loss by using perforated polyethylene bags (PPB). With or without removal of astringency by treatment with elevated carbon dioxide (CTSD method), forcing-cultured 'Tonewase' fruit produced significant amounts of ethylene two days after harvest ; thereafter, most fruit softened rapidly. This softening was markedly suppressed by treating the fruit with 1-methylcyclopropene (MCP), an inhibitor of ethylene action, which suggests the involvement of ethylene in fruit softening. Packaging 'Tonewase' fruit in PPB ranging from 0.03% to 0.3% of the total film surface area reduced water loss, retarded the commencement of ethylene production and delayed fruit softening. Immature field-grown 'Hiratanenashi' fruit behaved similarly to the forcing-cultured 'Tonewase' fruit with respect to ethylene production, softening and response to MCP treatment and PPB, whereas mature fruit under the same storage conditions produced no ethylene and remained firm during postharvest.
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  • Toshiki Asao, Hisashi Taniguchi, Kosuke Suyama, Hiroki Yamamoto, Kazuh ...
    2001 Volume 70 Issue 3 Pages 393-395
    Published: May 15, 2001
    Released: January 31, 2008
    JOURNALS FREE ACCESS
    The herbicide, 2, 4-dichlorobenzoic acid (DCLBA), was administered through the nutrient solution to six cucumber seedlings grown hydroponically. DCLBA, which is also a synthetic auxin, stunts cucumber plants at a low concentration but kills at a higher one. Roots of six comparable seedlings, treated with DCLBA, were exposed to two strains of microorganisms, TS-22 and TS-29, and Rhizoplane AC1, which were isolated from soils and cucumber roots. The control cucumber seedlings, unexposed to DCLBA and the different strains of microorganisms grew vigorously, whereas those exposed to DCLBA were stunted. The stature of seedlings, exposed simultaneously to DCLBA and TS-22, TS-29, and Rhizoplane AC1, was nearly that of the control, but their fresh and dry weights were approximately 2/3 and 1/2, respectively, of the untreated control seedlings. These results demonstrate that there are microorganisms in the soil and on cucumber roots which, if added to the nutrient solution, can catabolize DCLBA.
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