Journal of the Japanese Society for Horticultural Science
Online ISSN : 1880-358X
Print ISSN : 0013-7626
ISSN-L : 0013-7626
Volume 57 , Issue 1
Showing 1-16 articles out of 16 articles from the selected issue
  • Hiroshi INOUE, Yutaka HARADA
    1988 Volume 57 Issue 1 Pages 1-7
    Published: 1988
    Released: July 05, 2007
    JOURNALS FREE ACCESS
    One-year-old satsuma trees (cv. Okitsu Wase) on trifoliate orange were grown in a growth chamber where day and night temperature were kept constant at 15, 20, 25 and 30°C for 7 or 9 months. The effects of temperature on vegetative growth and nutrient absorption were investigated.
    1. Potted trees were transferred into the growth chamber in April and grown until late October of 1979. Budbreak occurred considerably earlier at higher temperatures. Trees at 15 and 20°C sprouted flushes only in spring and these shoots produced some flower buds during September through October. Trees at 25°C flushed spring, summer and autumn shoots, and those at 30°C had an additional cycle of flush. Total shoot length of the trees at 30°C was the greatest. Fresh and dry matter increased in both tops and roots with rising temperatures, but at 30°C they slightly decreased. The leaves of trees at 20°C contained the highest amount of nitrogen and phosphorus. Calcium and potassium contents increased as temperature rose. Other mineral contents examined were lowest at 15°C. Total amount of mineral elements absorbed by the trees increased with rising temperature from 15 to 25°C, but slightly decreased at 30°C
    2. Root growth was observed using root boxes (30×20×25cm) for 9 months from April through December, 1982. High temperature stimulated root growth. At 30°C trees grew rapidly and had five growth cycles for shoots and three for roots. In contrast, root growth of trees at 15°C was severely restricted. In all cases, root growth always followed shoot growth. The rate of root growth increased just after spring and summer flushes, and had two clear peaks, excepting in trees at 15°C. Root growth showed the same pattern at all temperatures above 20°C. At 15°C, however, roots grew slowly but continuously without any peaks. The higher the temperature. the greater the total root length obtained by the end of the experiment.
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  • Masahiko YAMADA, Isami IKEDA, Hiroyasu YAMANE, Toshio HIRABAYASHI
    1988 Volume 57 Issue 1 Pages 8-16
    Published: 1988
    Released: July 05, 2007
    JOURNALS FREE ACCESS
    Inheritance of fruit cracking of Japanese persimmon (Diospyros kaki Thunb.) was investigated using data collected over 30 years. The cracking which occurs at the calyx end and the stylar end is referred to as “Hetasuki”and “Kachorekka”, respectively.
    Varieties of PCNA (pollination constant non-astringent) were most likely to cause “Hetasuki” and/or “Kachorekka” cracking. The crosses between varieties showing no cracking resulted in the progenies with little or no cracking. However, crosses between varieties showing cracking resulted in wide range of segregation from non- to severe cracking. Similar results were obtained from crosses between varieties with and without cracking. Therefore, the heredity of the traits producing non-cracking fruit seems to be dependent on the homozygosity of the genes involved.
    Negative correlations were found between the percentage of progenies without cracking and the mean values of cracking of their parents; the correlation coefficients were -0.54** to -0.64** for “Hetasuki” and -0.68** to -0.76** for “Kachorekka.”
    The PCNA varieties which had been selected under breeding programs at Fruit Tree Research Station and whose traits had been examined for regional adaptability at many locations, also frequently exhibited “Hetasuki”and “Kachorekka” cracking.
    It is important to eliminate the progenies with severe cracking at early stages of selection, which will make the breeding of Japanese persimmon, notably of PCNA varieties, more efficient.
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  • Shin-ichi SHIRAISHI, Yuka WATANABE
    1988 Volume 57 Issue 1 Pages 17-21
    Published: 1988
    Released: July 05, 2007
    JOURNALS FREE ACCESS
    The anthocyanins of the tetraploid blue-black grapes, ‘Pione’, ‘Izunishiki’ and ‘Black Olympia’ were extracted with 1% HCl-methanol, and were purified by the lead acetate method. The individual pigments were separated by thin-layer chromatography. They were identified by their Rf values, molybdate shift and color reactions in the visible and ultra-violet regions. The co-existence of mono- and diglucosides, and the presence of p-coumaric acyl groups were indicated in all cultivars. The pigments in ‘Black Olympia’ consisted of eight anthocyanins as follows: delphinidin-, petunidin-and malvidin-3-monoglucosides, and acylated with p-coumaric acid, and malvidin-3, 5-diglucoside and acylated with p-coumaric acid. ‘Izunishiki’ contained ten anthocyanins, those of ‘Black Olympia’ plus petunidin-and delphinidin-3, 5-diglucosides with p-coumaric acids. ‘Pione’ contained fourteen anthocyanins, the same ten as ‘Izunishiki’ plus cyanidin- and peonidin-3-monoglucosides, and petunidin- and delphinidin-3, 5-diglucosides. The aglycone level pigments, in decreasing order of concentration, were malvidin, delphinidin, petunidin, cyanidin and peonidin, in ‘Pione’.
    In ‘Izunishi’ and ‘Black Olympia’, the aglycones were in about the same order, but cyanidin and peonidin were lacking.
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  • Fusao MIZUTANI, Ryuji HIROTA, Kazuomi KADOYA
    1988 Volume 57 Issue 1 Pages 22-27
    Published: 1988
    Released: July 05, 2007
    JOURNALS FREE ACCESS
    The effect of growth inhibitors from peach roots on the activity of β-cyanoalanine synthase was investigated. A positive correlation was found between the condensed tannin content and the inhibition of β-cyanoalanine synthase activity in the fractions of extract of peach roots. Ethyl-acetate-soluble neutral fraction, which showed the highest content of condensed tannins and the greatest inhibition of the enzyme activity, was further separated by Sephadex LH-20 column chromatography. Fractions containing high condensed tannins reduced the growth of rice seedlings and suppressed the activity of β-cyanoalanine synthase. One of the purified biflavanols, which were isolated from peach roots as growth inhibitors, also inhibited the β-cyanoalanine synthase activity. We inferred that when the growth inhibitors suppress this activity, the normal cyanide metabolism is disturbed, resulting in the accumulation of hydrogen cyanide in the tissues. Thus from an allelopathic point of view, the growth inhibitors derived from the root residues of preplanted peach trees adversely affect the growth of replanted trees by causing cyanogenesis in their roots.
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  • Naoki UTSUNOMIYA
    1988 Volume 57 Issue 1 Pages 28-33
    Published: 1988
    Released: July 05, 2007
    JOURNALS FREE ACCESS
    Young seedlings of 5 Psidium species grown under water stress and non-stress conditions for about 2 months were frozen at -5°C. In non water-stressed seedlings, dieback was only about 30% of stem length in P. cattleianum var. lucidum and P. guineense and leaf damage was least in P. cattleianum var. lucidum. On the other hand, the stems of P. polycarpum and P. friedrichsthalianum were almost completely killed by freezing. The degrees of stem dieback of two P. guajava cultivars were intermediate. Water stress further decreased the freeze injury of two tolerant species and P. guajava cv. ′Fahrang′, whereas still more than 70% of stem length was killed in the stressed seedlings of two sensitive species.
    In young guava (P. guajava) seedlings, the lower the leaf water potential, the greater the tolerance to freezing at-5°C. The treatment with water stress from Oct. and from Dec. effectively increased freeze tolerance, but the treatment from Aug. did not increase it. The season of water stress seems to influence cold hardiness. Water stress had little additional effect on the freeze tolerance of guava seedlings at -7°C.
    Sugar and proline concentrations in the leaves were increased by water stress. The involvement of their levels in the increased cold hardiness due to water stress was briefly discussed. Specific differences in cold hardiness of Psidiums could not be explained in terms of differences in the level of either sugar or proline in the leaves among species.
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  • Soo Nyeon KWACK, Kunimitsu FUJIEDA
    1988 Volume 57 Issue 1 Pages 34-42
    Published: 1988
    Released: July 05, 2007
    JOURNALS FREE ACCESS
    Unfertilized ovule culture for the production of somatic embryos and its histological observations were carried out in Cucurbita moschata. About 17% ovules produced somatic embryos when ovules, excised from the ovaries at anthesis which were pretreated at 5°C for 2 days, were cultured on a liquid half-strength Murashige and Skoog (MS) medium supplemented with MS organics and 30g/l sucrose. At the initiation of culture, the embryo sac began to degenerate. From about 10 days of culture, some of the nucellar cells became conspicuous by large nuclei, dense cytoplasm and thick walls, and divided to give rise to proembryos. Further cell division and differentiation of proembryos led to globular, heart and cotyledonary stages similar to zygotic embryogenesis. Among the obtained embryos, only a fewshowed normal morphology and many developmental variants were observed, such as embryos with secondary embryos or abnormal cotyledons. Upon transfer of the somatic embryos to the same nutrient medium supplemented with 5g/l sucroseand 8g/l agar, most of them underwent callusing, and only a few developed normal shoots and roots. The regenerated plants were diploid (2n=40) or tetraploid. Our histological and cytological investigations indicate that the embryos from cultured unfertilized ovules of C. moschata develop directly from single cells of the nucellus.
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  • Shinichi ADANIYA, Teruo HIGA
    1988 Volume 57 Issue 1 Pages 43-51
    Published: 1988
    Released: July 05, 2007
    JOURNALS FREE ACCESS
    Zingiber mioga Roscoe (2n=55) is a condimental vegetable originating in Japan. Cross breeding of this crop is difficult because of its low seed fertility. To investigate the cause of this low seed fertility, the effects of temperature, relative humidity (RH) and growth season on pollen germination and pollen tube growth in the style were examined in a laboratory.
    The optimum temperature for pollen germination in vitro ranged from 10 to 15°C, but the pollen tubes in the styles incubated at 20 or 25°C grew faster than in those incubated at 15 or 30°C.
    The percentage of pollen germination, the penetration into styles and the growth rate of pollen tubes increased as the relative humidity was elevated, and the best humidity for pollen longevity and pollen tube growth was at RH 100%. However, pollens which were stored at RH 60 or 80% for a few hours did not recover to the previous level of germinability, even by exposure to RH 100% prior to inoculation on the medium. Moreover, when spikes were exposed to RH 60% for 3 hours and pollinated with fresh pollen, pollen tube growth was also significantly inhibited.
    A high pollen fertility and a good pollen tube growth were observed in the growth season of January. Pollen fertility in June was as high as in January, while pollen tube growth in June was poor. On the other hand, in the hot summer of August and September, abortive pollen grains of small size increased and pollen tube growth diminished.
    From these results, we conclude that a favorable temperature and humidity for pollen activity and pistil receptibility may be in a range from 20 to 25°C and at RH 100%. In addition to these factors, it is also important for pollen activity that plants grow under cool conditions.
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  • Hideo IKEDA, Takaya OSAWA
    1988 Volume 57 Issue 1 Pages 52-61
    Published: 1988
    Released: July 05, 2007
    JOURNALS FREE ACCESS
    Two experiments were carried out to investigate the effects of CO2 concentration in the air and light intensity on the utilization of NO3 and NH4 by vegetable crops.
    In the first experiment, lettuce, tomato, and kidney bean were grown in a nutrient solution composed of various NO3/NH4 mixtures under several concentrations (360-1800ppm) of CO2 in the air. The growth of each crop was enhanced by CO2 enrichment and was better when plants were provided with N as a combination of NO3 and NH4 than with NO3 alone. Especially in tomato, growth enhancement by CO2 enrichment was greater with NH4 than with NO3.
    In the second experiment, cucumber, tomato, and spinach were grown in a nutrient solution containing N in various combinations of NO3 and NH4 under two levels of light intensity (unshaded, 40% shaded) and air CO2 concentration (360, 1300ppm); lower growth was obtained under the shaded condition. The growth of each crop was markedly increased by CO2 enrichment under unshaded higher light intensity. However, under the shaded condition, the effect of CO2 enrichment on spinach growth was small. When plants were grown with NO3 alone, increasing N concentration in the solution (2-12 me/l) produced little increase in dry weight at 360ppm CO2 irrespective of light conditions, but produced marked increase at 1300 ppm CO2. Greater growth increment owing to CO2 enrichment was produced with NH4 than with NO3. Furthermore, growth reduction due to shading was smaller with NH4 than with NO3.
    The results may suggest the possibility that NH4 is a more effective N source than NO3 under higher air CO2 concentration or lower light intensity. Moreover, N concentration in the solution needs to be kept relatively high to produce the yield increase by CO2 enrichment.
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  • Hideo IKEDA, Takaya OSAWA
    1988 Volume 57 Issue 1 Pages 62-69
    Published: 1988
    Released: July 05, 2007
    JOURNALS FREE ACCESS
    Tomato plants were grown in nutrient solution four times in two years on a practical scale in order to study the effects of NO3/NH4 ratios and temperature of the nutrient solution on growth, yields, and blossom-end rot (BER) incidence.
    In spring season crops, growth was best at 25°C. Combined application of NO3 and NH4 produced better growth than did NO3 alone except when plants were grown at low solution temperature and high NH4 ratio. However, the incidence of BER increased with the combined application of NO3 and NH4, and especially, the yields of normal fruits which had no BER were significantly decreased at high solution temperature and high NH4 ratios because of increased incidence of BER. Without exception, leaf Ca concentration was lower when plants were supplied with NO3 and NH4 than with NO3 alone; this seemed to be related to the incidenceof BER.
    In fall season crops, the yields of normal fruits were proportional to plant growth because of a low rate of BER incidence. Namely, in the low solution temperature the growth was better with a combination of NO3 and NH4 than with NO3 alone, and the yields of normal fruits were higher when plants were supplied with 12 me/l of N as a mixture (10/2 or 8/4) rather than the same amount of NO3. However, in the high solution temperature, increased ratios of NH4 to NO3 resulted in reduction of plant growth and of the yields of normal fruits. Leaf Ca concentration was decreased with increasing ratios of NH4 to NO3 in the solution, but no relationship between leaf Ca concentration and plant growth or BER incidence was observed.
    Thus, in practical hydroponic production of tomato, the nutrient solution should exclude NH4 in the warm season when BER may easily occur. In the cool season with low light intensity, however, solutions containing NH4 up to about one-third of total N may be recomended for promoting plant growth, keeping plant vigor, and increasing the yields of normal fruits.
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  • Yukihiro FUJIME, Yoshimitsu SAITO, Yasunobu NAKAYAMA
    1988 Volume 57 Issue 1 Pages 70-77
    Published: 1988
    Released: July 05, 2007
    JOURNALS FREE ACCESS
    Effects of growing temperatures (17°C-23°C) and day lengths (8 hours day length and 16 hours day length) on floral development was investigated. Thirteen broccoli cultivars differing in earliness of flower head formation were used.
    1. Two extremely early cultivars (‘Gokuwase-midori’ and ‘Green Comet’), three early cultivars (‘Shaster’, ‘Ryoku-yo’ and ‘Sato-midori’), and an intermediate cultivar (‘Ryoku-zan’), did not form flower heads under short-day conditions at temperatuers of about 20°C, but they formed flower heads long-day conditions at the same temperature.
    2. Two extremely early cultivars (‘Gokuwase-midori’ and ‘Dark Horse’), three early cultivars (‘Wase-midori’, ‘Shaster’ and ‘Ryoku-yo’), and an intermediate cultivar (‘Three Seven’), formed flower heads one week earlier under long-day conditions than short-day conditions at arund 17°C.
    3. When two early cultivars (‘Wase-midori’ and ‘Shaster’), and two intermediate cultivars (‘Ryoku-rei’ and ‘Three Seven’), formed flower heads at temderatures of about 17°C, the number of leaves to flower heads was smaller under long days than under short days.
    4. From these results, it may be considered that the low temperature treatment under long-day conditions promotes flower head formation more effectively than the same treatment under short-day conditions, and the temperature for photother mal induction is somewhat higher than for thermoinduction. As for photothermal induction of flower head formation in broccoli plants, it is estimated that low temperature treatment is more effective than long-day treatment.
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  • Toyohide TANAKA, Takatoshi MATSUNO, Masaharu MASUDA, Kiyoshi GOMI
    1988 Volume 57 Issue 1 Pages 78-84
    Published: 1988
    Released: July 05, 2007
    JOURNALS FREE ACCESS
    Effects of 4 levels of nutrient solution and 6 potting media on growth and chemical composition of plant parts of a Phalaenopsis hybrid, ‘(Dtps. Red Lip×Phal. Red Eye)×Phal. Culmination’ were examined.
    1. Phalaenopsis plants potted in Bora(pumice)+peat moss(3:1, v/v)mix were given 4 levels of nutrient solution. N, P, K, Ca and Mg concentrations in standard nutrient solution (St solution) were prepared at 231, 46.5, 117.3, 80.1 and 12.2ppm, respectively. Every solution was supplied with microelements at the same concentration. Plants grown with St solution showed better growth and flowering than those grown with 1/3 and 2/3 St solution. Plants grown with 4/3 St solution showed the best growth, but flowered later than the plants grown with St solution. N and K contents in the leaves increased with increasing levels of nutrient solution whereas Ca and Mg contents decreased.
    2. Phalaenopsis plants were potted in potting media and grown with 1/3 St solution. Six potting media were as follows: Bora+peat moss(3:1) mix, Bora+peat moss (2:1) mix, Bora+peat moss(1:1) mix, hemlock bark (well-decomposed), redwood bark (raw material) and sphagnum moss. Plants grown in sphagnum moss showed good growth. N, P, K, Ca and Mg contents (% dry weight) of leaves were 1.74, 0.18, 4.42, 1.13 and 0.48, respectively. Mg content appeared to be low. Plants grown in Bora+peat moss (1:1) mix were superior in growth and flowering to those in sphagnum moss. N, P, K, Ca and Mg contents (% dry weight) of leaves were 1.36, 0.18, 2.20, 1.34 and 1.75, respectively. Plants grown in Bora+peat moss (3:1) mix and Bora+peat moss(2:1) mix were inferior in growth to those grown in Bora+peat moss(1:1) mix. Plants grown in hemlock bark were superior in leaf growth and inferior in root growth to those grown in other potting media, and flowering of these plants was delayed. N, P, K, Ca and Mg contents (% dry weight) of leaves were 2.93, 0.24, 4.49, 0.50 and 0.32, respectively. N and K contents of these plants were high, while Ca and Mg contents were low. Plants grown in redwood bark were of lowest quality. Ca and Mg contents of leaves of these plants were also low.
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  • Toyohide TANAKA, Takatoshi MATSUNO, Masaharu MASUDA, Kiyoshi GOMI
    1988 Volume 57 Issue 1 Pages 85-90
    Published: 1988
    Released: July 05, 2007
    JOURNALS FREE ACCESS
    Effects of 4 levels of nutrient solution and 5 potting media on growth and chemical composition of plant parts of a Cattleya hybrid, C. Ray Park×Lc. Oakland ‘MARIA’, AM/AOS, were examined.
    1. Cattleya plants, av. 27.8g fresh wt, were potted in Bora (pumice) on Mar. 22, 1979, in 12cm diameter polyethylene pots. Twenty ml of nutrient solution was given weekly, 28 times from April 21 to Oct. 26. Nitrogen, phosphorus, potassium, calcium and magnesium were included in a standard nutrient solution (St solution) at concentrations of 231, 46.5, 117.3, 80.1 and 12.2ppm, respectively. Four treatments were as follows: 1/3St, 2/3St, St and 4/3St. Calcium, magnesium and microelements were included at the same concentration in all treatments. Rate of fresh weight increase was best in plants receiving St solution. Root growth of plants receiving 4/3St was slightly inferior to that of plants receiving St solution. Nitrogen, phosphorus and potassium in the leaves increased with increasing concentrations of nutrient solution.
    2. Cattleya plants, av. 27.7g fresh wt, were potted on Mar. 22. 1979, in 12cm diameter polyethylene pots. Five potting media were as follows: Bora+peat moss (3:1)mix, Bora+peat moss (2:1)mix, Bora+peat moss (1:1)mix, hemlock bark (well-decomposed) and sphagnum moss. Twenty ml of 1/3St solution per pot was given weekly, 28 times from April 21 to Oct. 26. Plants grown in Bora+peat moss (1:1) mix grew best. Nitrogen phosphorus, potassium, calcium and magnesium contents (% dry weight) of leaves were 1.20, 0.17, 1.86, 1.14, and 0.92, respectively. Rate of fresh weight increase and root growth of plants grown in sphagnum moss and hemlock bark were inferior to those of plants grown in Bora+peat moss(1:1) mix. Magnesium content of leaves of plants grown in sphagnum moss and hemlock bark was 0.57 and 0.50%, respectively. These magnesium values seemed to be low as compared to those of leaves of plants grown in Bora+peat moss (1:1) mix.
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  • Masa-atsu YAMAGUCHI, Norihiko TERAHARA, Mitsuo KAKEHI, Ken-ichi SHIZUK ...
    1988 Volume 57 Issue 1 Pages 91-100
    Published: 1988
    Released: July 05, 2007
    JOURNALS FREE ACCESS
    The anthocyanin in the purplish-red flowers of carnation (Dianthus caryophyllus) has been considered for many years as cyanidin 3-glucoside (Cy 3-G). However, from chromatographic studies on the flower color in carnation, we previously found that the major anthocyanin was not Cy 3-G but an acylated one attached to an unknown organic acid.
    In the present studies, we have isolated and crystallized this anthocyanin from purplish-red flowers of carnation and analyzed it by chemical and spectroscopic means. This pigment was identified as cyanidin 3-malylglucoside (Cy 3-MG). Furthermore, by means of direct chromatographic comparison with this pigment, it was also found that Cy 3-MG was widely present in the purplish-red flower cultivars and in the same color hybrids which were obtained from intervarietal crossing of carnations.
    In addition, we have recently identified another anthocyanin, peralgonidin 3-malylglucoside (Pg3-MG) from a red flower carnation cultivar. Therefore, these results strongly suggest that malylation of anthocyanin is characteristic in the flowers of carnation.
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  • Yasuji YOSHIDA, Yukiko YAMADA, Motoko UEDA, Takuji ITO, Hidemi IZUMI
    1988 Volume 57 Issue 1 Pages 101-108
    Published: 1988
    Released: July 05, 2007
    JOURNALS FREE ACCESS
    Mikan wine was tentatively made from satsuma mandarin (Miyagawa Wase Unshiu) fruits to be used for various purpose.
    Changes in some properties of must for mikan wine were investigated serialy as the day goes on during their fermentation period by mixed yeast or ER yeast (Saccharomyces cervisiae ER, wine yeast). The mixed yeast was prepared by mixing OC-2 yeast (Saccharomyces cervisiae IFO 2260, wine yeast) with W 3 yeast (Saccharomyces cervisiae IFO 2116, distillery yeast).
    (1) The mixed yeast and ER yeast propagated satisfactorily themselves in the must for mikan wine at 13±5°C from 5 to 15 days with the mixed yeast and from 5 to 17 days with ER yeast after these yeasts were inoculated in the must for mikan wine, respectively. After that, the propagation of these yeasts became weak little by little and then the must for mikan wine was cleared up with settlings of their body.
    (2) Most of alcohol was produced from 7 to 20 days with the mixed yeast and from 9 to 25 days with ER yeast after the inoculation of these yeasts. After that, alcohol contents remained at same levels and reached finally to about 13% by volume. Alcohol production was amounted to 0.52%/day with ER yeast and 0.72 %/day with the mixed yeast at the peak of alcohol production.
    (3) Specific gravity of the must for mikan wine was changed a little in their values and their refractmeter index was rapidly decreased in their values from 22 to 7% in about 11 days at the peak of alcohol production. Total sugar was comsumed much in it′s amounts from 1.07 to 1.21g/100ml/day. Changes in sucrose, glucose and fructose in the must for mikan wine were investigated by another experiment. Sucrose and glucose were consumed rapidly at early stage and fructose was consumed slowly at later stage. There were difference in the consumption among sucrose, glucose and fructose.
    Titratable acid increased in a little in it′s contents and pH values and citric acid remained at same levels. Malic acid was decreased in it′s contents from 2.2g/l at early stage to 0.8g/l at later stage. On the other hand, lactic acid was increased from 1.6 to 2.5g/l for 33 days. From the relation between malic and lactic acid mentioned above, it was considered that malo-lactic fermentation was occured in the must for mikan wine. There will be still room for futher study on this phenomenon.
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  • Bing-Shan FUH, Takao ICHII, Tetsu NAKANISHI, Yoshitaka KAWAI
    1988 Volume 57 Issue 1 Pages 109-115
    Published: 1988
    Released: July 05, 2007
    JOURNALS FREE ACCESS
    Seasonal changes in lipid composition in the flavedo tissues of Naruto fruit were determined during August to early June.
    Total fatty acid content of phospho- and glycolipids, particularly that of glycolipids, decreased considerably with increased aging of the rind except during midwinter. In mid-winter that of neutral, phospho- and glycolipids showed a sharp peak, due largely to an increase in linoleic (18:2) acid in the first two and linolenic (18:3) acid in the last.
    Content of major phospholipids, phosphatidylcholine (PC) and phosphatidylethanolamine (PE); and content of major glycolipids, mono-(MGDG) and di-galactosyl-diglyceride (DGDG), behaved in a way similar to that of phospho- and glycolipid total fatty acids, respectively. Seasonal variations in DGDG content were paralleled by, but greater than MGDG content. The PC/PE ratio decreased steadily from August to December and thereafter remained unchanged. Free sterol content decreased from August to October and thereafter changed little except for showing a peak in mid-winter. However, the sterol/phospholipid ratio was relatively constant during winter. The sitosterol/stigmasterol ratio more than doubled in the maturing period (December-June) compared with that in the growing period (August October).
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  • Tomoaki MATSUO, Keiko OKA, Saburo ITOO
    1988 Volume 57 Issue 1 Pages 116-121
    Published: 1988
    Released: July 05, 2007
    JOURNALS FREE ACCESS
    With the purpose of getting much information about the mechanism of leakage observed at the onset of plant senescence or other physiological disorders, a model system using red beet discs has been investigated in our study. The present paper describes the effects of various chemicals added to the incubation medium, in which red beet discs are exposed or pre-exposed to tert. -butylhydroperoxide (BHP), on the leakage of red betacyanin pigment from the cells. The mechanism of betacyanin leakage induced by the BHP treatment is suggested from these results.
    1. Under the same conditions reported in our previous paper, the treatment with BHP (10mM and 8hrs) evidently caused the abrupt increase of OD 540nm (leakage of red betacyanin pigment), and the optical density reached about 1.0 from 5hrs to 7hrs after the treatment.
    2. The addition of 5mM sodium diethyldithiocarba mate, 20mM thiourea, 5.0mM (+)-catechin and 1mM n-propyl gallate, separately, to the incubation medium effectively inhibited the increase in OD 540nm, when each chemical and BHP were added simultaneously.
    3. L-Cysteine (5mM) and D-ascorbic acid (5mM), which are well known as endogenous reducing agents, also showed the inhibitory effect on Betacyanin leakage of red beet discs.
    4. When (+)-catechin (5mM), cysteine (10mM) and thiourea (20mM) wereadded, separately, to the incubation medium in the absence of BHP after the BHP treatment (10mM and 8hrs), they also showed significant effects on inhibition of betacyanin leakage.
    5. The presence of 5mM EDTA or 2.5mM FeCl3 in the incubation medium containing 10mM BHP enhanced the increase in OD 540nm considerably.
    These results suggest that BHP taken into the discs of red beet, as indicated in the red cells of human blood, may be transformed by either free Fe3+, chelated Fe3+ or other endogenous unknown factors to the tert. -butoxyl radical, and consequently will attack various biomembranes in the cells to cause the lakage of red betacyanin pigment. Further biochemical investigation will be required to confirm the mechanism.
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