Japanese Journal of Phytopathology
Online ISSN : 1882-0484
Print ISSN : 0031-9473
ISSN-L : 0031-9473
Volume 44 , Issue 3
Showing 1-21 articles out of 21 articles from the selected issue
  • Kiyoshi YORA
    1978 Volume 44 Issue 3 Pages 228-230
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Download PDF (331K)
  • Natsuki NISHIHARA
    1978 Volume 44 Issue 3 Pages 231-234
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
  • Kan-ichi OHATA
    1978 Volume 44 Issue 3 Pages 235-237
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
  • Takeshi NARITA
    1978 Volume 44 Issue 3 Pages 238-240
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
  • Kimio SUZUKI, Minoru TAKAHASHI
    1978 Volume 44 Issue 3 Pages 241-246
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Zoospores of Pythium aphanidermatum were strongly attracted by crude exudates from cucumber roots and then encysted. When the root exudates were fractionated, chemotactic substances were found to be unadsorbed by 0.5% activated charcoal and soluble in 80% hot ethyl alcohol. These substances were also ethyl ether insoluble and cationic. By paper chromatographic bioassay and amino acid analysis for this cationic fraction, serine and glutamic acid showed zoospore attraction and encystment. Serine was more chemotactic agent than glutamic acid, but it was impossible to clarify the mechanism of attraction of P. aphanidermatum zoospores toward cucumber roots within seconds in terms of serine and glutamic acid. Chemotactic response was also found by the extracts of rhizosphere soil of cucumber. This may indicates that another chemotactic substances may exist in the extracts of rhizosphere soil besides amino acids found in cucumber root exudates.
    Download PDF (1088K)
  • Toshihiro OMURA, Satoshi WAKIMOTO
    1978 Volume 44 Issue 3 Pages 247-254
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Among stock calli successively transferred for 70 generations at 30 days intervals, the green colored compact calli containing high concentration of tobacco mosaic virus (TMV) vigorously differentiated shoots when they were transferred to a differentiation medium. However, TMV-eliminated translucent calli derived from TMV-containing green calli by successive transfers of the translucent part of the tissue showed no sign of differentiation.
    TMV-eliminated translucent callus became greenish and compact when the selected greenish and compact peripheral tissue was successively transferred on the medium containing higher concentration (2mg/l) of kinetin. Transfers with longer intervals (50 days) and incubation under higher intensity of light (3, 000-12, 000lux) promoted the change. TMV-eliminated green and compact callus thus obtained acquired the ability of differentiation.
    All the plantlets differentiated from the 6 year-old callus were aneuploid. However, virus-free plantlets obtained from newly established virus-eliminated callus were diploid (2n=48).
    Download PDF (1447K)
  • Mamoru SATO
    1978 Volume 44 Issue 3 Pages 255-261
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Five lysogenic strains in Pseudomonas mori, the pathogen of bacterial blight of mulberry, were detected by plating and other methods. Each temperate phage isolated from these lysogenic strains was named as φ5, φ6, φ7b, φ7c and φM5, and their properties were investigated.
    Both φ7b and φ7c showed a broader host range and were spontaneously produced to attain higher concentrations (106 to 107/ml) as compared to others from each parent bacterial strain after shaking culture for 24 hours at 28C. Plating efficiency was markedly influenced by the bacterial strain used as indicator.
    All the phage isolates formed plaques at the temperature range of 5 to 28C. Three isolates, φ7b, φ7c and φ5, formed small round and turbid plaques of about 0.5mm in diameter at 20C of optimum growth temperature, while others formed medium-sized round and comparatively clear plaques of 1 to 2mm in diameter.
    Both φ7b and φ7c were extreamely heat stable, showing thermal inactivation point of 95C for 10min., and sensitive to chloroform, while other isolates were inactivated at about 50C and resistant to chloroform.
    From the foregoing properties, these phage isolates were classified into three groups, A, B and C, respectively including φ6 and φM5, φ5, andφ7b and φ7c.
    Each lysogenic strain did not lose its lysogeny even by 15 times repeated single colony isolation or passing mulberry leaves. The lysogeny was also independent from colony type mutation from smooth to rough. Several mutants appeared to be defective lysogenic strain were obtained during the course of this experiment.
    Download PDF (1256K)
  • Yasushi TAKAGI
    1978 Volume 44 Issue 3 Pages 262-269
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    An investigation was made on the inhibitory effect on tobacco mosaic virus (TMV) infection exerted by the aqueous extract from the cultre of Flammulina velutipes grown in the saw dust-rice bran medium. The extract was noted to have an inhibitory activity in fractions of a wide range eluted from the Sephadex G-75 column. The molecular weight of an active substance in the extract was presumed to be 15000-50000 from the elution pattern on the Sephadex column chromatogram. The fractions with an inhibitory activity showed positive color reaction to protein and sugar. Such activity remained unchanged even after the procedure to remove protein or protease treatment. This suggests that the activity of the substance depends primarily on sugar. Detected as a result of thin-layer chromatography of hydrolyzate of the above fractions were galactose, glucose, mannose, xylose and an unidentified sugar. The inhibitory activity of the extract varied somewhat according to test plants. TMV infection was inhibited not only by the application of the mixture of the extract and TMV to plant leaves but also by its application prior to virus inoculation. In case the extract was applied after virus inoculation, however, it failed to exhibit satisfactory effect. Its inhibitory effect by the pre-treatment was diminished when the treated leaves were washed before virus inoculation. Dilution of the mixture of the extract and TMV with water resulted in restoration of virus infectivity. When the above mixture was eluted through the Sephadex G-75 column, virus infectivity was recognized in fractions containing TMV.
    Download PDF (879K)
  • Masao GOTO, Tamio SHIRAMATSU, Kazutoshi NOZAKI, Kunio KAWAGUCHI
    1978 Volume 44 Issue 3 Pages 270-276
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Bacterial wilt of strawberry caused by Pseudomonas solanacearum has been observed in nurseries in some areas of Shizuoka Prefecture, killing around 30 percent seedlings at most every year. The symptoms found on the cultivar HOKO WASE under the natural conditions were the acute wilting of the younger leaves, resulting soon in total death of the plants. The cultures isolated from the diseased plants were identified as the pathovar 8a (biovar III) and 4 (biovar IV). In the inoculation tests, however, the disease development was rather mild and slow regardless of the inoculation techniques such as the prick method or the immersion method in which the root systems or the cut-end of runners were dipped into the bacterial suspensions for 10min. The pathogen could survive in the tissues of some inoculated plants until next spring. The reisolation trials made 8 to 10 months after inoculation revealed that the rates of the carrier plants were about 10% in the cultivar FUKUBA and 5% in HOKO WASE. In most cases, these plants grew as vigorous as the non-inoculated healthy plants and set fruits normally. In the diseased plants, either under the natural conditions or artificially inoculated, plugging by bacterial cells was usually restricted to only a small number of tracheary elements in a xylem tissue, where the cell walls were often broken down forming bacterial pockets. It was remarkable that the bacterial fissures were often observed in the parenchymatous tissues of the infected stems even when the invasion of the vascular tissues was slight.
    Download PDF (1869K)
  • Toshihiro OMURA, Satoshi WAKIMOTO
    1978 Volume 44 Issue 3 Pages 277-281
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Tobacco callus tissues infected with potato virus X (PVX), potato virus Y (PVY) or cucumber mosaic virus (CMV), tomato callus tissue infected with tobacco mosaic virus (TMV) or potato callus tissue infected with PVX were established respectively from the stems of inoculated plants. These tissues were successively transferred under the suitable conditions for proliferating either compact tissue or soft tissue, and the virus concentrations in the tissues were periodically assayed. In all the host-virus combinations tested, virus concentration in callus tissues rapidly decreased under the conditions of producing friable callus. Generally, the virus concentration was maintained at high level in compact callus. However, CMV in tobacco callus tissue and TMV in tomato callus tissue decreased rapidly even under the conditions to grow compact callus.
    Download PDF (585K)
  • Yasushi TAKAGI, Katsuro OGAWA
    1978 Volume 44 Issue 3 Pages 282-287
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Nineteen nonionic surface active agents were tested for their inhibitory effects on tobacco mosaic virus (TMV) infection to Nicotiana tabacum L. cv. Xanthi-nc. The hydrophilic-lipophilic balance (HLB) values of the chemicals tested varied from 4.7 to 16.7, showing no significant relationship between inhibitory activities and HLB values. However, in the group of polyoxyethylene nonylphenol ethers with HLB values varying from 9.2 to 17.5 the inhibitory activity was the highest at HLB 13.7. Inhibitory activity of the chemicals depended also upon the structure of hydrophobic group, i.e., nonylphenol group was the most effective among alkylphenol groups, and lauryl was the most effective among alkyl groups. Polyoxyethylene nonylphenol ether, HLB 13.7, was the most effective among 19 chemicals tested. Examination on the action mechanism of polyoxyethylene nonylphenol ether, HLB 13.7, revealed that the chemical interferes with the attachment of the virus particles to infectible sites of the host and/or conversion of the infectible sites to infective centers.
    Download PDF (621K)
  • Masanobu NAKATA, Kenzo FUKUNAGA, Naoji SUZUKI
    1978 Volume 44 Issue 3 Pages 288-296
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Polyacrylamide gel electrophoresis of the solubilized protein of rice dwarf virus (RDV), purified from RDV-infected rice plants, showed the virus to be composed of seven structural polypeptides. The molecular weights of these were calculated to be 193, 000; 152, 000; 131, 000; 110, 000; 62, 000; 46, 000 and 45, 000 daltons. These were designated I, II, III, IV, V, VI, and VII respectively. Chymotrypsin-treatment of the virus was not effective for removing the outer components of capsid, whereas centrifugation of the virus through preformed cesium chloride gradients separated the preparation into four zones, top (T), upper-middle(M1), lower-middle (M2), and bottom (B), the buoyant densities of these being 1.26, 1.39-1.42, 1.43, and 1.46g/ml respectively. Recentrifugation of M1 through the cesium chloride gradients yielded three zones, M1, M2, and B, indicating that the latter two resulted from M1 by the shearing effect of cesium chloride centrifugation. Electron microscopy and SDS-polyacrylamide gel electrophoresis of B showed complete loss of II and IV, and a marked decrease of VI and VII, indicating that VI and VII compose the outer capsomeres and II and IV are the amorphous polypeptides that surround the outer capsomeres. The inner core was found to contain I, III, and V, among these V seemed to be the internal protein associated with nucleic acid because this was readily released from virions by freeze-thawing together with nucleic acid.
    Download PDF (2324K)
  • Osamu HORINO
    1978 Volume 44 Issue 3 Pages 297-304
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    To investigate distributions of pathogenic strains of Xanthomonas oryzae in Japan, isolates collected from various areas of Japan in 1973 and 1975 were examined by the qualitative virulence test on four differential varieties of rice. Two hundreds and fifty-nine isolates were classified as group I, 128 as group II, 36 as group III, 3 as group IV, and one as group V. Group I and II were found to distribute widely in almost all areas. Group III distributed in Yamanashi and Nagano prefectures, and the western part of Japan; especially it was found frequently in Nagano, Kumamoto, and Kagoshima prefectures. In 1975, 3 isolates of group IV were found in Nago-city, Onna-village of Okinawa prefecture, and Nagasaki-city, while one isolate of group V in Gokase-twon of Miyazaki prefecture. In Kyushu-Okinawa region, all of the five groups distributed and among them group II was found most frequently. Such a high incidence of group II in this region may be attributed to predominant cultivation of Kogyoku group varieties which can be attacked by group II. It is readily assumed that cultivated varieties in certain regions are a major factor to determine the distributions of bacterial groups. However, the present results that groups II to IV which can attack Kogyoku group varieties were found in regions where Kinmaze group varieties had been cultivated extensively, suggest that some other factors must be involved in determining distributions of bacterial groups. Further studies should be done to examine effects of these factors such as environment and cultivation conditions on distributions of bacterial group. To investigate associations between virulences of bacterial isolates and their host varieties, 66 isolates collected from Kyushu region were further categorized, based on their host varieties. Among 42 isolates from Kinmaze group varieties, 18 isolates were identified as group I, 17 isolates as group II, 6 isolates as group III, and one isolate as group V, while among 24 isolates from Kogyoku group varieties, 20 isolates were identified as group II and 4 isolates as group III.
    Download PDF (1562K)
  • Katsuyoshi YONEYAMA, Tomomasa MISATO
    1978 Volume 44 Issue 3 Pages 305-312
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    The mechanism of action of sodium dimethyldithiocarbamate (NaDMDC) was examined by using Xanthomonas oryzae, the causal pathogen of bacterial leaf blight on rice plant. The result showed that NaDMDC inhibited selectively the incorporation of 14C-acetate into the lipids of X. oryzae, and this inhibition was exerted more strongly when the cells were active in metabolism. Also, NaDMDC inhibited nonspecifically the incorporation of radioactive precursors into all lipid components of cells. In the phosphatidylethanolamine from 14C-glucose labeled cells, labeling of the fatty acid constituent, rather than the glycerlyphosphorylethanolamine constituent, was markedly inhibited by NaDMDC. However, NaDMDC did not inhibit the incorporation of radioactive long-chain fatty acids into the phospholipids of cells. These results suggested that the process from long-chain fatty acids to phospholipids was not affected by NaDMDC. Thus, the primary action of NaDMDC may be involved in the fatty acid synthesis of X. oryzae.
    Download PDF (941K)
  • Katsuyoshi YONEYAMA, Shigeko SEKIDO, Tomomasa MISATO
    1978 Volume 44 Issue 3 Pages 313-320
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    The previous studies made on the mode of action of sodium dimethyldithiocarbamate (NaDMDC) showed that the compound inhibited the lipid synthesis of Xanthomonas oryzae, but not the process from long-chain fatty acids to phospholipids in the biosynthetic pathway of lipids. Further examinations were made on the effects of NaDMDC on the process from acetate to fatty acid formation. NaDMDC inhibited neither the two kinds of enzymes involving in the formation of acetyl CoA from acetate, acetate kinase and phosphotransacetylase, nor the enzyme concerning in the synthesis of malonyl CoA from acetyl CoA, acetyl CoA carboxylase. However, the compound had a high inhibitory effect on the incorporation of 14C-malonyl CoA into fatty acids, in either the fatty acid-synthesizing enzyme system of Escherichia coli or the cellfree extracts of X. oryzae.
    From these results, it is concluded that NaDMDC inhibits primarily the fatty acid synthesis of X. oryzae, and gives a remarkable influence upon the entire lipid biosynthesis.
    Download PDF (975K)
  • L.S. LEU
    1978 Volume 44 Issue 3 Pages 321-324
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    A new pathogenic strain No.3 was obtained by artificial hybridization of sporidia of Ustilago scitaminea between pathogenic strains No.1 and No.2. Pathogenic strain No.3 attacked both NCo310 and F134, which were susceptible only to strain No.1 and strain No.2, respectively.
    If the inoculated cuttings were kept in room temperature (26-28C) for a few days before planting, only one of the two strains (either No.1 or No.2) could be recovered from the newly developed whips resulting from the inoculation with a mixture of teliospores of both strains on the compatible varieties.
    Further studies on the compatibility of U. scitaminea revealed that all tested 5 sets of sporidia isolated from 5 teliospores showed two mating types with two allele systems. Compatible matings resulted in mycelial growth on colonies.
    Download PDF (446K)
  • Toshikazu TANI, Hiroyuki YAMAMOTO, Yoshitaka OHASA, Youko YAMASHITA
    1978 Volume 44 Issue 3 Pages 325-333
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Non-host responses of primary leaves of oat seedlings (cultivar Shokan 1) following inoculation with uredospores of fourteen rust fungi were investigated. Of the rust fungi used, six were pathogenic on gramineous plants and the remainders were nonpathogenic on any of gramineous plants. The fungi of the former group, except Puccinia zoysiae, differentiated high numbers of appressoria over stomata and produced substomatal vesicles in stomata cavities equally well as the infection with the pathogen, Puccinia coronata avenae. In contrast, all fungi belonging to the latter group failed to grow towards stomata and consequently no essential penetration through stomata occurred. The development of the fungi non-pathogenic on oat within oat leaf tissues was inferior to that of the incompatible race of the pathogen. The difference between both was statistically significant before the haustorium formation could be expected. The previous inoculation of the leaves with the five rust fungi of the former group markedly inhibited the development of the normally compatible race of the pathogen. The incorporation of 3H-uridine and 14C-leucine into the acid insoluble fraction was greater at 12 or 16hr after inoculation in the leaves invaded by these fungi, as compared with corresponding non-inoculated controls. Administration of either the RNA synthesis or protein synthesis inhibitor, cordycepin or blasticidin S, into the leaves stimulated the development of these fungi. It was therefore postulated (a) that the failure of stomata infection of rust fungi that were non-pathogenic on gramineous plants was attributable to the lack of specific relationships between the fungi and the surface features of oat leaves, and (b) that the restricted development of the fungi that were pathogenic on gramineous plants was due, at least in part, to the activation of defense mechanism induced in the leaf tissues.
    Download PDF (989K)
  • Hiroshi YANO, Hiroshi FUJII, Hideo MUKOO, Tsuguaki FUKUYASU, Tetsuro W ...
    1978 Volume 44 Issue 3 Pages 334-336
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Download PDF (307K)
  • Mitsuro IWAKI
    1978 Volume 44 Issue 3 Pages 337-339
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Download PDF (346K)
  • Akira SHIRATA, Kokichi TAKAHASHI, Kohei TOMIYAMA
    1978 Volume 44 Issue 3 Pages 340-343
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Download PDF (324K)
  • 1978 Volume 44 Issue 3 Pages 344-406
    Published: July 25, 1978
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Download PDF (11459K)
feedback
Top