Japanese Journal of Phytopathology
Online ISSN : 1882-0484
Print ISSN : 0031-9473
ISSN-L : 0031-9473
Volume 47 , Issue 5
Showing 1-17 articles out of 17 articles from the selected issue
  • Teruo SANO, Matsuo SASAKI, Eishiro SHIKATA
    1981 Volume 47 Issue 5 Pages 599-605
    Published: December 25, 1981
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Hop stunt viroid (HSV), cucumber pale fruit viroid (CPFV) and potato spindle tuber viroid (PSTV) were inoculated to 11 test plants in Cucurbitaceae, Solanaceae and Compositae. Both HSV and CPFV developed symptoms on cucumber (Cucumis sativus), C. melo, Benincasa hispida, Lagenaria siceraria var. clavata and L. siceraria var. microcarpa. Cucumber plants infected with HSV and CPFV showed stunting, vein clearing and leaf curling 14-17 days after inoculation. The other 4 plants in Cucurbitaceae also showed stunting, leaf curling and top necrosis 16-22 days after inoculation, and severely infected plants semetimes died. It was found that tomato plants caused symptomless infection by HSV and CPFV. In tomato plants, concentration of HSV was lower than that in cucumber plants. No seed transmission was detected in HSV infected tomato. On the other hand, tomato plants infected with PSTV developed severe stunting and epinasty about 14 days after inoculation, but cucumber, C. melo, B. hispida, L. siceraria var. clavata, L. siceraria var. microcarpa, Citrullus vulgaris and Cucurbita moschata in Cucurbitaceae were not infected with PSTV. Similar scanning patterns of nucleic acid extracted from HSV and CPFV infected tomato (cv. Rutgers) were shown on 5% polyacrylamide gel electrophoresis, and infectivity assays from the gel fractions indicated that the migration rates of HSV and CPFV were almost identical. In this experiment, however, HSV and CPFV displayed identical migration rate with 7S RNA from healthy plant extracts, and thus no viroid-specific band was observed. Whereas, extractions from PSTV infected tomato displayed a typical specific band on 5% polyacrylamide gel electrophoresis, and PSTV activity was associated with this band. The results obtained indicated that pathogenic properties and molecular weight of HSV were very similar to those of CPFV. and different from those of PSTV.
    Download PDF (1862K)
  • Yosuke MINO, Ryutaro SAKAI, Akira TAMURA
    1981 Volume 47 Issue 5 Pages 606-610
    Published: December 25, 1981
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Chlorogenic acid was hydrolyzed to caffeic and quinic acids, and caffeic acid was further decarboxylated to 3, 4-dihydroxystyrene by the enzymes prepared from the timothy leaf spot fungus, Cladosporium phlei. Neither chlorogenic acid hydrolase nor caffeic acid decarboxylase was inducible.
    Download PDF (200K)
  • Tsutomu MATSUMOTO
    1981 Volume 47 Issue 5 Pages 611-617
    Published: December 25, 1981
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    The relative activities of IgM and IgG antibodies against cucumber green mottle mosaic virus-watermelon strain (CGMMV-W) in rabbits were examined by complement fixation test at different stages during the course of immunization. The immunogen was administered at one week intervals by three different methods; intramuscular injection with Freund's complete adjuvant, intravenous injection with PolyA·PolyU as adjuvant and intravenous injection without adjuvant. Regardless of the immunization methods used, the antibody activities of IgM and IgG fractions were almost the same, and/or the IgM antibodies were a little less on the third week after the first injection. Later on the fourth week, as the activity of IgG increased, that of IgM markedly declined or was not detected. These results thus suggest that early bleeding at 3 weeks after the first injection would produce relatively more specific IgM antibodies by intravenous injection, whereas late bleeding after hyperimmunization is better for the IgG antibodies against CGMMV-W.
    Download PDF (368K)
  • Masao GOTO, Katsushi YAMANAKA
    1981 Volume 47 Issue 5 Pages 618-626
    Published: December 25, 1981
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Twenty-one amino acids were identified in the intercellular fluids taken from healthy citrus leaves. Quantitative analysis was made on the changes in the concentration of these amino acids after inoculation of Xanthomonas campestris pv. citri. The amino acids detectable in a significant amount in citrus leaf tissues were tested for their role in bacterial growth. Met was an essential factor needed for growth of the bacterium and the optimum concentration was in the range of 0.05 to 0.1μmol per ml which corresponded to the amount detected in the intercellular fluids. In the presence of met, several amino acids such as asp, asn, glu, val, leu, and pro were utilized by the bacterium as nutrient. Pro was particularly important because it was the major amino acid found in the intercellular fluid of citrus leaves, and it increased rapidly after the infection of citrus trees with the bacterium. The concentration several days after inoculation became 10 times higher than that of noninoculated healthy leaves. On the other hand, ser and hylys were also important because of their ability to inhibit the growth of the bacterium. This activity was, however, prevented by the presence of two amino acids, met and pro, at concentrations equivalent to those in the intercellular fluids. Sensitivity to ser and hylys was higher in the virulent isolate than that in the avirulent isolate. Pro prevented more effectively the growth inhibition of the virulent isolate than that of the avirulent isolate. The activity of pro synergistically increased by the coexistence of ala, although ala itself did not have such an effect. The concentration of pro in the leaves of Fortunella japonica, resistant to citrus canker, was lower than that of susceptible Citrus natsudaidai leaves, but the reverse phenomenon was observed with ser. The higher ratio of ser: pro may be responsible for induction of the strong resistance of this plant to citrus canker.
    Download PDF (4488K)
  • Hiroshi KAMIUNTEN, Satoshi WAKIMOTO
    1981 Volume 47 Issue 5 Pages 627-636
    Published: December 25, 1981
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    The effects of the infection with filamentous phage Xf2 on the properties of Xanthomonas campestris pv. oryzae N5850 were investigated. The bacteria infected with Xf2 released the phage into medium to reach the maximum concentration of about 1×1011 PFU/ml after 48hr of shaking culture. The multiplication of bacteria was considerably retarded by infection with Xf2 at temperatures lower than 33.5C. The infected bacteria, however, reached the same or higher level as compared with uninfected control later on. The infected cells grew even at 35C to some extent, while the uninfected cells did not. The Xf2-infected bacteria grown at different temperatures of 30, 33.5 and 35C for 72hr were ultrathin sectioned and their structural change was investigated with electron microscope. Although no remarkable difference was observed between Xf2-infected and uninfected cells in cytoplasmic structures, the cell wall of the former was vesiculated, denatured or partially stripped from the cells. The Xf2-infected bacteria multiplied in the inoculated rice leaves more slowly than uninfected bacteria during the first few days after inoculation. The former's population, however, exceeded the latter later on. The Xf2-infected bacteria incited symptoms on rice leaves earlier than uninfected bacteria. No difference was observed between Xf2-infected and uninfected bacteria in activities of xylanase, cellulase and lipase in culture filtrates. The amout of extracellular polysaccharide produced by Xf2-infected bacteria was higher than that produced by uninfected bacteria, suggesting some correlation with virulence.
    Download PDF (4594K)
  • Katsuhiko ANDO, Keizo KATSUYA
    1981 Volume 47 Issue 5 Pages 637-645
    Published: December 25, 1981
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    The satisfactory growth of colonies from wheat leaf segments infected with urediniospores of Puccinia recondita f. sp. tritici and placed on the medium was observed in cultures growing at 10, 15, 20 and 25C in darkness. The following morphological characteristics of the colonies were observed: colonies which grew in darkness at 15, 20 and 25C had a felt-like appearance and the others which developed at 10 and 15C in darkness had a muciform appearance. The muciform colony, designated as “reproductive colony”, consisted mainly of sporogenous cells and urediniospores. At 30C in darkness, colony growth from rust infected leaf segments on the medium was not observed. Light inhibited the mycelial growth of cultures grown at 20C and given an illumination at about 1, 000lux for 16hr per day. The vegetative growth colony (Prt 51-2-4) developed well at 10, 15, 20 and 25C in darkness, with the optimal temperature being 25C. However, it did not grow in darkness at 30C. Urediniospores, which were produced in the colony cultured at 10C in darkness for more than 3 months, were able to infect wheat seedlings.
    Download PDF (4980K)
  • Michiaki IWATA, Yasuharu SEKIZAWA, Hisako IWAMATSU, Yukio SUZUKI, Tets ...
    1981 Volume 47 Issue 5 Pages 646-653
    Published: December 25, 1981
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    The relationship between plant hormones and shift of peroxidase activity in the rice blast lesion was investigated using a compatible race-cultivar combination. Peroxidase activities in the leaf tissues were increased by the application of auxins, ethylene or their precursors, especially at the inoculated site. When kinetin was subsequently applied, the increase in the peroxidase activity by IAA or ethylene was enhanced, on the other hand, the increase by IAA or ethylene was suppressed by the subsequent application of ABA. The degree of rice blast incidence was suppressed by the application of auxins, ethylene or their precursors. The suppression of blast incidence by IAA or ethylene was strongly counteracted by the application of ABA prior to inoculation. The metabolic inhibitors such as formycin A, cycloheximide and blasticidin S caused considerable inhibition of IAA-or ethylene-induced increase in peroxidase. The hypothetical role of plant hormones on induced disease resistance of rice plant was proposed.
    Download PDF (432K)
  • Nobuaki MATSUYAMA, Takuji KOZAKA
    1981 Volume 47 Issue 5 Pages 654-661
    Published: December 25, 1981
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    In an incompatible combination of rice cultivar and blast fungus race, the rapid increase of peroxidase activity of rice leaves occured within 24hr after inoculation, while a little or no increase was observed in a compatible case at early stage of infection. However, sudden increase occured at 3-5 days after inoculation in a compatible combination and the activity exceeded that of an incompatible combination. These alteration of activities occured more rapidly in aged leaves. The highest activity was observed at the time of rapid lesion enlargement in compatible case. The isozymes activated by the infection were fixed, and no new isozyme specific to compatible or incompatible combination was detected. The distinct difference between both combinations was the time of increase started. The ample supplies of nitrogenous fertilizer reduced the degree of resistance to rice blast disease. However, peroxidase activities increased with the doses of N-fertilizer and the highest activity was observed at the highest dose, i. e., under the most susceptible condition. These results indicate that the increase of peroxidase activity is possibly the reflection of host cell collapse or physiological disorder and may not be directly involved in the resistance mechanism.
    Download PDF (423K)
  • Yasuko SHIBA, Toshimi NAGATA
    1981 Volume 47 Issue 5 Pages 662-667
    Published: December 25, 1981
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Tricyclazole [Beam®, 5-methyl-1, 2, 4-triazolo (3, 4-b)-benzothiazole], a new systemic fungicide registered recently in Japan for the control of rice blast caused by Pyricularia oryzae Cav., hardly inhibited the mycelial growth, conidial germination and appressorial formation of P. oryzae at concentrations less than 125ppm, but it protected the plants almost completely from the disease by foliage application at as low as 10 to 20ppm. Rice seedlings in a seedling box 60×30×4cm were treated with tricyclazole through the soil at a dosage of 2.5g as 75% wettable powder per box one week before transplanting. They were satisfactorily protected from the infection for about one month after transplanting; tricyclazole content was estimated to be about 3 to 8ppm. The basic fraction of petroleum extracts from the treated rice leaves was found to have considerably high inhibitory action against the conidial germination of P. oryzae, although no tricyclazole was detected. These results suggest the possibility that an antifungal substance may be produced in leaves treated with tricyclazole.
    Download PDF (343K)
  • Jae Eul CHOI, Kenichi TSUCHIYA, Nobuaki MATSUYAMA, Satoshi WAKIMOTO
    1981 Volume 47 Issue 5 Pages 668-676
    Published: December 25, 1981
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    The colony type variants of Xanthomonas campestris pv. oryzae derived from wild type during subculture on PSA medium were greatly different in virulence one another and most of them were attenuated as compared to wild type. Virulence of these variants was closely related with colony types, serological properties, autoagglutination in 1% CaCl2 solution, phage sensitivity and ability of slime polysaccharide production. In general, the colony type variants Lw (large, smooth, waxy yellow) and Lh (Large, dark yellow, with halo) of serovar A produced greater amount of slime polysaccharide and were more virulent than the variants St (small, transparent) and Sm (small, mucoid) of serovar B-II. The variants Ld (large, dark yellow) and Lh of serovar B-I were intermediate between serovar A and B-II in virulence and polysaccharide production. Avirulent and weakly virulent variants of serovar B-I and B-II agglutinated remarkably in 1% CaCl2 solution while wild type and virulent variants did not. No correlation was observed between their bacteriological properties and pathogenic specialization. Weakly virulent and avirulent variants interfered with wild type to suppress symptom expression. The decrease of virulence during subculture of X. campestris pv. oryzae was considered to be mainly caused by the population increase of weakly virulent and avirulent variants and partially caused by interference of these variants to wild type in symptom expression.
    Download PDF (450K)
  • Hiroshi YAEGASHI, Koichi ASAGA
    1981 Volume 47 Issue 5 Pages 677-679
    Published: December 25, 1981
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Download PDF (177K)
  • Yasuyuki TETSUKA, Keizo KATSUYA, Makoto KAKISHIMA
    1981 Volume 47 Issue 5 Pages 680-684
    Published: December 25, 1981
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Download PDF (5441K)
  • Yuichi YAMAOKA, Keizo KATSUYA, Yasuyuki TETSUKA
    1981 Volume 47 Issue 5 Pages 685-687
    Published: December 25, 1981
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Download PDF (2737K)
  • Fumiyoshi FUKUMOTO, Hiroshi TOCHIHARA
    1981 Volume 47 Issue 5 Pages 688-690
    Published: December 25, 1981
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    By freeze-drying, the infectivity of crude extracts of plants infected with tomato spotted wilt virus was reduced to 4% of the original infectivity, whereas the preparations containing 1% cysteine maintained 81% of their original infectivity. Freeze-dried preparations of crude extracts or plant tissues lost their infectivity after preservation for 4 months at 4C, while the preparations containing 1% cysteine remained infectious for 24 months.
    Download PDF (197K)
  • Osamu TAMURA, Izumi SAITO
    1981 Volume 47 Issue 5 Pages 691-693
    Published: December 25, 1981
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Download PDF (2437K)
  • Tadaoki INABA, Toshihiko HINO
    1981 Volume 47 Issue 5 Pages 694-696
    Published: December 25, 1981
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Download PDF (159K)
  • Shinji KAWANO, Toshihiro SENBOKU, Eishiro SHIKATA
    1981 Volume 47 Issue 5 Pages 697-699
    Published: December 25, 1981
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Rice ragged stunt virus (RRSV) was inoculated to 9 species of Gramineae by viruliferous brown planthoppers, Nilaparvata lugens (Stål). Five species, such as maize, wheat, barley, rye and common millet were infected and developed symptoms, similar to those on rice, e.g. twisted leaf, ragged leaf and stunting. Only 1 out of 10 inoculated oat plants and 2 out of 15 japanese millet plants developed slight ragged leaves about one month after inoculation, but no virus was recovered by back inoculation to rice and by electron microscopic detection. No infection occurred on sorghum and Coix lachryma-jobi var. ƒrumentacea.
    Download PDF (1935K)
feedback
Top