Journal of the Japanese Society for Horticultural Science
Online ISSN : 1880-358X
Print ISSN : 0013-7626
ISSN-L : 0013-7626
Volume 71 , Issue 5
Showing 1-21 articles out of 21 articles from the selected issue
  • Ryutaro Tao, Tsuyoshi Habu, Hisayo Yamane, Akira Sugiura
    2002 Volume 71 Issue 5 Pages 595-600
    Published: September 15, 2002
    Released: January 31, 2008
    JOURNALS FREE ACCESS
    Self-compatible cultivars of Japanese apricot (Prunus mume Sieb. et Zucc.) have a common S-RNase (Sf-RNase) gene that can be used as a molecular marker for self-compatibility. In this study, we further characterized Sf-RNase by comparing S-RNase of self-compatible 'Kensaki' (SfSf) and self-incompatible 'Nankou' (S1S7). cDNA libraries from the styles with stigmas of these two cultivars were constructed and cDNAs encoding Sf-, S1-, and S7-RNases were cloned. Deduced amino acid sequences from these cDNAs all contained two active domains of the T2/S type RNase family and five conserved regions of the rosaceous S-RNase. RNA blot analysis showed that the Sf-, S1-, and S7-RNase genes were transcribed in the pistil but not in the leaf as with other S-RNase genes of Prunus. Furthermore, 2D-PAGE analysis revealed that Sf-RNase has molecular mass, isoelectric point, and immunological characteristics similar to other S-RNase. These results indicate that the pollen-S gene that is supposedly tightly linked to the Sf-RNase gene may be responsible for the self-compatibility observed in the Sf-haplotype.
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  • Kipkoriony L. Rutto, Fusao Mizutani, Doo Gyung Moon, Kazuomi Kadoya
    2002 Volume 71 Issue 5 Pages 601-609
    Published: September 15, 2002
    Released: January 31, 2008
    JOURNALS FREE ACCESS
    It has been demonstrated that soil disturbance, excessive fertilization and the use of some agrochemicals affect the survival and function of arbuscular mycorrhizal (AM) fungi. To clarify the effect of different cultural practices on mycorrhizal activity in orchards, spore population dynamics, soil and plant mineral content and mycorrhizal infection were surveyed monthly from May to October, 2000 in kiwifruit, Japanese chestnut, Iyo tangor, satsuma mandarin, Japanese persimmon, apple, peach, Japanese plum and grape plantings, subjected to different management regimes. In intensively managed orchards, levels of major elements in the soil were generally high, owing to periodic fertilization ; consequently, the content of these elements in the leaves was within the recommended range for normal growth and function. High levels of AM infection were maintained throughout the season in the apple orchard that received no fertilizer or fungicide. The infection levels on roots of kiwifruit vines decreased in July and August after three fungicide sprays in June ; it also decreased in Iyo tangor in July following four fungicide applications in May and June. These orchards had no under-story cover plants. However, the infection level of peach trees under sod culture remained relatively high even after five fungicide sprays from May through August. Thus, population density of AM spores in the soils seems to be low in the clean cultivated orchards, subjected to frequent fungicide sprays, whereas it was high under sod culture. We conclude that excessive fertilization, frequent fungicide sprays and clean culture have an adverse effect on AM spore populations and tree infection in orchards.
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  • Haruyuki Kuroda, Toshihiko Sugiura, Daiyu Ito
    2002 Volume 71 Issue 5 Pages 610-616
    Published: September 15, 2002
    Released: January 31, 2008
    JOURNALS FREE ACCESS
    Hydrogen peroxide (H2O2) content was determined in flower buds of Japanese pear (Pyrus pyrifolia Nakai cv. Kosui) trees under natural conditions during the development and their release from endodormancy. H2O2 content increased gradually as the developmental stage index (DVI) accumulated, peaking in late December when endodormancy was broken ; it then decreased during the ecodormancy stage. In unchilled flower buds from November 1 throughout the winter, H2O2 content did not change significantly and remained low. No budbreak was observed at the end of March which indicate that the increase in the level of H2O2 during chilling is closely associated with the breaking of endodormancy. H2O2 levels induced by applying hydrogen cyanamide to flower buds of cuttings throughout the endodormancy period promoted budbreak. This was accompanied by a depletion of H2O2 within one day, followed by a large increase 3-6 days later. However, cyanamide treatments at concentrations that had no promoting effect on budbreak resulted in a decrease in H2O2 content during the experimental period. The cumulative budbreak 22 days after cyanamide treatment was positively correlated with H2O2 content six days after the treatment, indicating that the endodormancy-breaking effect of cyanamide involves the elevation of H2O2 similar to that of chilling temperatures. These results suggest that H2O2 can substitute for the chilling requirement, and that the increase in H2O2 levels may trigger the sequence of reactions involved in the breaking of endodormancy.
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  • Jie Chen, Tadashi Ito, Yutaka Shinohara
    2002 Volume 71 Issue 5 Pages 617-622
    Published: September 15, 2002
    Released: January 31, 2008
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    The effects of cell shape of plug trays on shoot and root growth of Chinese cabbage 'Fuyu Touge' transplants were investigated. The cell shapes were : round, pentagonal, square, and triangular ; holding equal volumes of the growing medium. Root circling of the plug transplants was fastest in round cells and slowest in triangular ones. At the second leaf stage, roots grew better in round cells, had higher N and K contents and respiratory activity than did those of other shapes. No significant difference was found in shoot growth of the plants among shapes. However, at the third leaf stage, the plants grown in round and triangular cells had smaller roots with lower N, K and P contents than did those in pentagonal and square ones. Root respiratory activity and photosynthetic rate were unaffected by cell shape. At the fourth leaf stage, shoot grew slower in round cells, had a lower K and P contents, and a reduced photosynthetic rate compared to others. No significant difference was observed in plant growth between pentagonal and square cells at any growth stage. The growing medium in round cells had the lowest water-holding capacity, followed by pentagonal, square, and triangular ones.
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  • Masahito Shimonaka, Takashi Hosoki, Motonori Tomita, Yoshimasa Yasumur ...
    2002 Volume 71 Issue 5 Pages 623-631
    Published: September 15, 2002
    Released: January 31, 2008
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    Interspecific somatic hybrids between Japanese bunching onion (Allium fistulosum L., 2n=2x=16) and bulb onion (A. cepa L., 2n=2x=16) were produced by the electorofusion of protoplasts. A concentration of iodoacetamide (IOA), suitable for inhibiting the formation of colonies from protoplasts in Japanese bunching onion, was used. IOA-treated protoplasts of Japanese bunching onion and untreated protoplasts of bulb onion were mixed together and fused, with the expectation that only heterokaryons would selectively develop into colonies. Four hundred and seventeen colonies had formed from fusion products after a 45- day culture, of which approximately 80% developed into calli. Plant regeneration was achieved in 33 out of 325 (10.1%) calli. Some regenerants expressed abnormalities, but two were successfully transplanted in a greenhouse. Cytogenetical and DNA analyses revealed these two regenerants to be amphidiploids (2n=4x=32). Furthermore, it was shown that another three regenerants possessed the nuclear genome of Japanese bunching onion, whereas, their chloroplasts were from bulb onion. The application of these hybrids to a breeding program for Japanese bunching onion is discussed.
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  • Takejiro Takamura, Ikuo Miyajima
    2002 Volume 71 Issue 5 Pages 632-637
    Published: September 15, 2002
    Released: January 31, 2008
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    The origin of tetraploids from 4x × 2x cyclamen crosses was examined by using the diploid pollen parents with and without giant pollen grains, and by pollinating tetraploid cultivars with sieved giant and normal-sized pollen grains borne on diploid plants. The developing pollen mother cells were observed after the second meiotic division in the diploids with and without the giant pollen grains. Tetraploid progeny production in the crosses was obviously related to the giant pollen grains. Tetraploid F1 progenies were produced in the crosses by using pollen from diploid plants that produce giant pollen ; no seed was obtained in the crosses by using pollen from diploids, which produce no giant pollen. More seeds were obtained when sieved giant pollen grains were used for the crosses than when non-sieved pollen grains with giant pollen were used, whereas no seed was obtained in the crosses using only normal-size pollen grains from diploids. Thirteen to 27% of pollen mother cells in the diploids with giant pollen grains formed pollen dyads or triads after the second meiotic division, whereas few pollen dyads and triads were formed in those without giant pollen grains. These observations suggest that most giant pollen grains in diploid cyclamen are unreduced male gametes. Therefore, the origin of tetraploids derived from 4x × 2x cyclamen crosses is the results of fertilization between an unreduced pollen grain from the diploid plant and a normally reduced egg cell from the tetraploid. Furthermore, the use of sieved giant pollen grains was efficient for the production of tetraploid progenies.
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  • Yusuke Kosugi, Keisuke Waki, Yujiro Iwazaki, Nanako Tsuruno, Atsushi M ...
    2002 Volume 71 Issue 5 Pages 638-642
    Published: September 15, 2002
    Released: January 31, 2008
    JOURNALS FREE ACCESS
    Cut flowers of a transgenic carnation (Dianthus caryophyllus L.) line (sACO-1 line), which was transformed with a carnation 1-aminocyclopropane-1-carboxylate (ACC) oxidase cDNA in sense orientation (sACO transgene), had a longer vase life than had flowers of the non-transformed plant and produced only a negligible amount of ethylene during natural senescence. The suppressed ethylene production in sACO-1 line was not accompanied with the accumulation of mRNA for ACC oxidase (DC-ACO1) gene in the gynoecium or mRNAs for DC-ACO1 and ACC synthase (DC-ACS1) genes in the petals. Previously, it was shown that in naturally senescing carnation flowers, ethylene is first produced from the gynoecium ; the evolved ethylene, acting as a diffusible signal which is perceived by petals, induces the expression of DC-ACO1 and DC-ACS1 genes that results in autocatalytic ethylene production in the petals (Shibuya et al., 2000). The results indicate that sACO transgene inhibits the expression of DC-ACO1, probably by cosuppression in the gynoecium, which then suppresses ethylene production in all flowers of sACO-1 line.
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  • Yoshimi Yonemoto, Hirokazu Higuchi, Yoshinobu Kitano
    2002 Volume 71 Issue 5 Pages 643-650
    Published: September 15, 2002
    Released: January 31, 2008
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    Respiration and ethylene production rates of cherimoya fruit were measured under various temperature regimes. The highest ethylene production was observed at 15°C and 20°C ; it was restricted at 30°C and 35°C in 'Libby' fruit. The numbers of days required for fruit ripening at 15°C and 20°C were 9-11 days and 8 days, respectively. The optimum ripening temperature for cherimoya fruit ranged from 15 to 20°C. To determine the optimum storage period, fruit from five cultivars of cherimoya were initially stored at 10°C for 20 days and then ripened at 20°C. 'Bay Ott' and 'Big Sister' ripened normally, while 'Chaffey', 'El Bumpo' and 'Mariella' turned brown and their quality declined. It was found that 'Bay Ott' and 'Big Sister' were more resistant to chilling injury than other cherimoya cultivars. Coating the fruit with wax revealed that it reduced respiration and ethylene production of the fruit, and extended the shelf life by 5 days, with less weight loss and minimal browning.
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  • Hiroyasu Kitashiba, Narumi Matsuda, Takako Ishizaka, Hideaki Nakano, T ...
    2002 Volume 71 Issue 5 Pages 651-657
    Published: September 15, 2002
    Released: January 31, 2008
    JOURNALS FREE ACCESS
    The C-repeat (CRT) dehydration responsive element (CRT/DRE) is a cis-acting DNA element, which stimulates transcription in response to low temperature and drought stress. Recently, the DREB1/CBF (regulatory factor that binds to the CRT/DRE elements and promotes expression of multiple low-temperature-induced genes resulting in cold-acclimation) has been identified in Arabidopsis thaliana L. We have isolated a genomic clone from Prunus avium L. (sweet cherry) that was predicted to include three DREB1/CBF-like genes. Two (D2A and D2B) of the genes were deduced to have a complete open reading frame (ORF) and the other (D2Ctr : truncated D2C) was deduced to have an incomplete ORF. Each putative protein had an EREBP/AP2 DNA binding domain motif and a potential nuclear localization signal in the N-terminal region. Furthermore, the D2A and the D2B proteins had an acidic C-terminal region. The D2A and the D2B proteins were found to be 53 and 53.5% identical to DREB1B/CBF1, respectively. However, the EREBP/AP2 conserved domain of the three D2 proteins showed a high identity (74-79%) with that of each DREB1/CBF. In addition, the TATA-box and G-box sequences, and MYB- and MYC-recognition sites were predicted along with in the 5' other conserved sequences of all three genes. The expression of the D2 genes was found to be induced by low temperature in P. avium.
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  • Yoshihide Yamakawa
    2002 Volume 71 Issue 5 Pages 658-660
    Published: September 15, 2002
    Released: January 31, 2008
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    Random amplified polymorphic DNA (RAPD) analysis was applied to a Japanese grape cultivar 'Koshu' and nine selected self-pollinated progenies. The RAPD analysis, using 18 primers, resulted in identical banding patterns with one primer but different banding patterns with the other primers. A total of 108 bands, including three novel bands that were not found in the patterns of the parent, were detected. Percentage similarity between each pair of vines ranged from 68.4% to 90.8%. The similarity values among progenies were comparatively low, whereas those between progenies and parent were comparatively high. Therefore, the data indicate that diversity among the nine vines of the self-pollinated seedlings was as broad as between pre-existing cultivars.
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  • Takuya Tetsumura, Kosuke Tsukuda, Koshiro Kawase
    2002 Volume 71 Issue 5 Pages 661-663
    Published: September 15, 2002
    Released: January 31, 2008
    JOURNALS FREE ACCESS
    Micropropagation of three cultivars of Shinano walnut (Juglans regia L.) was performed by using DKW medium. Nodal segments (explants) produced new shoots on DKW medium supplemented with 5μM BA and 0.05μM IBA. When subcultured, shoots grew better on the above medium with agar than they did with Gelrite. There was a significant difference in the growth of shoots among the cultivars. To induce roots, IBA-treated shoots were transferred to a rooting medium, a Gelrite-solidified DKW medium with macroelements reduced to 1/4 strength, with or without vermiculite. The addition of vermiculite to the medium improved the rooting percentage and promoted the development of a good root system. All regenerated plantlets were successfully acclimatized.
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  • Xiaoneng Zhuo, Shuji Shiozaki, Tsuneo Ogata, Shosaku Horiuchi
    2002 Volume 71 Issue 5 Pages 664-669
    Published: September 15, 2002
    Released: January 31, 2008
    JOURNALS FREE ACCESS
    The relationship between the formation of tendrils and leaf morphology was investigated in the seedlings of a wild grape, Ebizuru [Vitis ficifolia Bunge var. lobata (Regel.) Nakai], 'Campbell Early' (V. labruscana Bailey), and 'Kyoho' (V. labruscana Bailey). All grapes tested had a 144° spiral phyllotaxis before the formation of tendrils (juvenile phase), but alternate phyllotaxis after the formation of tendrils (transition phase). The morphology of the leaves represented by Galet's index did not differ before and after tendril formation. However, the number of serrations at the leaf margin increased at the higher nodal position before tendril formation. The node numbers bearing the first tendril were 26.8, 28.7, and 30 in the seedlings of Ebizuru, 'Campbell Early', and 'Kyoho', respectively. The number of serrations per leaf increased gradually after the formation of tendrils (adult phase) in the seedlings of 'Campbell Early' and 'Kyoho', but very slowly in Ebizuru. The serration grew deep and their angles became small with each succeeding nodal position. The depth of the sinus before and after tendril formation did not differ between seedlings of 'Campbell Early' and 'Kyoho', but it increased after the tendril formation in Ebizuru.
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  • Hiroshi Tamai, Takashi Ono, Hiroo Koike, Izumi Shigehara
    2002 Volume 71 Issue 5 Pages 670-674
    Published: September 15, 2002
    Released: January 31, 2008
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    M.9 is the most commonly planted rootstock in high density apple orchards in the world. However, M.9 rootstock has not been used in Japan because of infection with apple chlorotic leaf spot virus (ACLSV). M.9Nagano, an ACLSV-free clone and called M.9 minus was developed at the Nagano Fruit Tree Experiment Station. The growth, yield efficiency and fruit quality of the graft combinations, 'Fuji'/M.9Nagano and 'Fuji'/M.9Nagano (interstock)/Marubakaido were compared for 8 years at the Nagano Fruit Tree Experiment Station. Trees of 'Fuji'/M.9Nagano with rootstock half-buried developed into small trees, whereas those of 'Fuji' on M.9Nagano/Marubakaido with 30 cm of interstem half-buried grew vigorously. Limbs of the latter crossed severely so that every second tree was removed after the 6th year, resulting in a 4×4 m planting. No significant difference in fruit quality was noticeable between trees on M.9Nagano and M.9Nagano/Marubakaido. In conclusion, 8-year-old 'Fuji' trees on M.9Nagano are thought to be well adapted for 2×4 m or higher planting density under 40 to 50 cm layer of gravelly brown lowland soil condition.
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  • Toru Maruo, Yutaka Shinohara, Masatoshi Iwata, Tadashi Ito
    2002 Volume 71 Issue 5 Pages 675-682
    Published: September 15, 2002
    Released: January 31, 2008
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    The influence of nutrient concentration on the uptake of each nutrient by butter head lettuce plants (Lactuca sativa L. 'Okayama Salad') was investigated by using a NFT system. The solution volume in the NFT system was maintained constant automatically by supplying deionized water. The nutrient uptake was calculated from the decreasing rate of the nutrient concentration in the system. The NO3-N, PO4-P and K uptake rates by the lettuce plant were relatively stable within a comparatively wide range of nutrient concentrations, i.e., the nutrient uptake rates were not influenced directly by the nutrient concentrations. When the nutrient concentration was above 1 me·liter-1, the uptake rate of each nutrient was unaffected by its concentration. The high ratio of the apparent uptake rate of NH4-N in comparison with other nutrients indicates a preferential uptake of NH4-N. From the environmental and managerial point of view, nutrient concentrations in a hydroponic production system should be lowered.
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  • Yuka Nakano, Shin-ichi Watanabe, Kunio Okano, Jiro Tatsumi
    2002 Volume 71 Issue 5 Pages 683-690
    Published: September 15, 2002
    Released: January 31, 2008
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    Tomato seedlings were grown in a Wet-sheet culture (WSC), where roots developed in the wet atomosphere, or in a Deep flow technique (DFT), where roots were submerged in the solution. They were grown in growth chambers kept at a constant 15, 25, and 35°C. The adaptability of the root systems in the WSC and DFT to high or low temperature was evaluated by comparing the root activity and structure of the systems. Dissolved oxygen in the nutrient solution of DFT was above that normally required for the plants. At all temperatures, tomato plants in WSC grew larger than did those in DFT. The bleeding rate of xylem sap on cut stem was higher in WSC than in DFT at 15°C and 35°C, the root respiration rate per dry weight was higher in DFT than in WSC at all temperatures. The root systems in WSC had more first order laterals and higher projected areas than had in DFT at 15°C and 35°C ; root growth in both systems were similar at 25°C. The fractal dimensions of root systems, known as an index for describing root system morphology, were higher in WSC than in DFT at 15°C. These results indicate that roots in the wet atomosphere would adapt more readily to high or low temperatures than did those in the solution.
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  • Noritoshi Katsutani, Shinji Kajihara, Hirokazu Hara
    2002 Volume 71 Issue 5 Pages 691-696
    Published: September 15, 2002
    Released: January 31, 2008
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    This study was conducted to determine the duration of exposure to low temperature required to induce bolting of rosetted seedlings and subsequent emergence of lateral buds in Elatum hybrids of Delphinium. When seedlings of 'Blue Springs', which rosettes from autumn to winter, were exposed to natural low temperature until December 5 or 15, plants bolted earlier under long days after being transferred to the greenhouse kept above 10°C than those under natural day length. This result means that exposure to low night temperature below 7°C for 30 days was required to induce bolting of rosetted seedlings, whereas the long day treatment after heating hastened flowering. Lateral buds on the base of main stems were induced to elongate and bolt when plants were exposed to 5°C at night for 30 days after cutting back the main stems in 'Blue Springs' and 'Magic Fountains Sky Blue'. When they were grown above 10°C, they produced 2.1-2.2 inflorescences/plant which flowered 70-74 days after heating. Lateral buds on the base of secondary shoots emerged without rosetting after secondary flowers were harvested in early April and flowered about 2 months later.
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  • Takahiro Tanigawa, Naohiko Kuroyanagi, Toshihiro Kunitake
    2002 Volume 71 Issue 5 Pages 697-701
    Published: September 15, 2002
    Released: January 31, 2008
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    Research was conducted to determine the effects of various temperatures, their duration, and lighting conditions for imbibed seeds on germination and bolting of Eustoma cultivars. After imbibed seeds of 'Tenryuwhite' were kept for 0, 1, 3 and 5 weeks at 11°C in the dark or light and brought to 30/20°C (day/night), their germination rate increased with low temperature treatments for 3 or 5 weeks compared to the control (with a 50% germination rate). The highest germination rate was 64.9% for the 5-week treatment at 11°C in the dark or light, and then brought to 30/25°C, the respective bolting rate of 'Asukanoasa' and 'Asukanosakura' control plants were 12.5% and 0%. Low temperature treatments for imbibed seeds accelerated bolting of both cultivars. The maximum bolting rate was 100% for 'Asukanoasa' after a 5-week treatment in the dark or 3 weeks in the light, and 85.7% for 'Asukanosakura' for a 5-week treatment in the dark. When imbibed seeds of 'Asukanosakura' were exposed to 2.5, 5, 10, 15°C for 0, 3, 5, 7 weeks, all those kept at 10°C for 5 weeks bolted and flowered, whereas no control plants responded. Hence, the flowering rate of Eustoma seedlings is affected both temperature and its duration.
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  • Yoichi Morinaka, Yasumasa Takatsu, Mikio Hayashi
    2002 Volume 71 Issue 5 Pages 702-709
    Published: September 15, 2002
    Released: January 31, 2008
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    The floral scents of 26 samples from 13 freesia (Freesia hybrida hort.) cultivars were evaluated by sensory evaluation of untrained panelists (30-64 persons). A seven-point bipolar scale with 32 descriptors was used for the evaluation. Uniformity and reproducibility of ratings on these scales had been confirmed by the evaluation of 30 different types of flower scent by an untrained panel. A five-point monopolar scale with 8 descriptors was also used. These are newly designed scales for evaluating freesia flower scent. As a first step in statistical analyses of sensory data, the panelists (their evaluations) were investigated by principal components analysis (PCA) and the outliers were eliminated. Then the uniformity of ratings among assessors was evaluated by using split-half coefficients. The detectability for differences among freesia samples was confirmed by 1-way ANOVA. As a result, 29 (12 bipolar scales and 5 monopolar scales) descriptors having high concordance and resolution were selected. PCA was carried out on the matrix of mean ratings for the selected sensory attributes. The PC score plots showed that the scent profiles of the freesia samples of the same cultivar were similar to each other, indicating that untrained panelists can be taught to evaluate floral scent of freesia cultivars using original scales.
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  • Kohei Nakano, Nobutaka Nakamura, Takeo Shiina, Shigenori Maezawa
    2002 Volume 71 Issue 5 Pages 710-715
    Published: September 15, 2002
    Released: January 31, 2008
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    Responses of respiration and C2H4 production in young soybean and cherry tomato fruits to an abrupt decrease in O2 concentration was investigated. The rates of O2 consumption, CO2 evolution and C2H4 production under ambient atmosphere and when O2 concentration was abruptly decreased from 21% to 3.5% were compared. A mathematical model, which assumes the exponential gas exchange with the time after the completion of O2 gas replacement, fitted well with the experimental data. The response rate constant K, which was newly defined, enabled the quantitative evaluation of the response to low O2 atmosphere. K values for O2 consumption, CO2 evolution and C2H4 production differed ; CO2 evolution had the lowest K value among gases. Moreover, K value for CO2 evolution depended on the species and maturity. These results may be attributed to the differences in O2 metabolism and physical properties, such as gas solubility, skin permeability and tissue structure.
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  • Kenji Murakami, Hiromi Orita, Masaharu Masuda
    2002 Volume 71 Issue 5 Pages 716-718
    Published: September 15, 2002
    Released: January 31, 2008
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    The varietal differences in response to continuous light exposure of Cucurbita plants were investigated in relation to antioxidative enzymatic activity. In cultivars of C. moschata except 'Butternut', chlorosis did not occur, and plants grew vigorously even at 24/0 hr. Chlorosis developed at the 3-leaf stage in C. moschata 'Butternut' and the two cultivars of C. maxima at 24/0 hr. Activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase in the 3rd true leaf were determined in 'Butternut' (C. moschata sensitive to continuous light) and 'Hyuga No.14' (C. moschata tolerant to continuous light) at the 3rd leaf stage. In 'Butternut', the activities of SOD and APX at 24/0 hr were 4-and 2-fold higher than those at 12/12 hr, respectively, whereas catalase activity was slightly higher at 24/0 hr. The hydrogen peroxide content in leaves was also higher at 24/0 hr. In 'Hyuga No.14', no differences were noted between the two photoperiodic treatments in these antioxidative enzymatic activities and hydrogen peroxide content. These results indicate that continuous-light induced oxidative stress is associated with leaf injury in 'Butternut'.
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  • Hiromi Hanada, Toshiaki Kayano, Hiroshi Tanaka, Yutaka Tabei
    2002 Volume 71 Issue 5 Pages 719-721
    Published: September 15, 2002
    Released: January 31, 2008
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    Fifteen cultivars of sweet pea (Lathyrus odoratus L.) were classified using a highly sensitive RAPD method which labels amplified DNA fragments by digoxgenin (DIG-RAPD). A conventional RAPD procedure, utilizing agarose gels, detected 960 PCR fragments by using 96 primers, whereas the AE-RAPD method performed by acrylamide gel electrophooresis, detected 199 fragments by 16 primers. The DIG-RAPD detected 335 PCR fragments using 16 primers indicating that it is about 2.1 times and 1.7 times more sensitive than the ordinary RAPD and AE-RAPD, respectively. Frequency of polymorphic DNA fragments generated by AE-RAPD and DIG-RAPD methods were 18.6 and 19.7%, respectively. Moreover, each UPGMA clustering analysis from ordinary RAPD, AE-RAPD and DIG-RAPD showed similar patterns. These results indicated that DIG-RAPD is an efficient RAPD method to detect polymorphic PCR fragments using fewer primers. It could also efficiently and quickly generate RAPD markers from closely related varieties, such as the sweet peas.
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