All issues
Volume 40 (1974)
- Issue 5 Pages 383-
- Issue 4 Pages 277-
- Issue 3 Pages 159-
- Issue 2 Pages 79-
- Issue 1 Pages 1-
Volume 40, Issue 5
Displaying 1-13 of 13 articles from this issue
- |<
- <
- 1
- >
- >|
-
Toshiro NAKANISHI, Yukiyoshi TAKAHI, Kazuo TOMITA1974 Volume 40 Issue 5 Pages 383-391
Published: December 25, 1974
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSThe metabolism of hymexazol (3-hydroxy-5-methylisoxazole) in soil was studied by using 14C-labeled chemical (14C-labeled at the 3 position on the isoxazole ring) to obtain fundamental information on its persistence in disease controlling activity and on residue analysis. Radioactive hymexazol was degraded in the unsterilized soil, and three radioactive metabolites were identified with carbon dioxide, acetoacetamide, and 5-methyl-2(3H)-oxazolone. The amount of 14CO2 evolved from radioactive hymexazoltreated soil increased with time, whereas those of the other metabolites decreased. The breakdown of hymexazol in unsterilized soil is biological, since only a trace of 14CO2 was evolved from the sterilized soil. Production of 14CO2 was remarkable in submerged condition compared to that in moist one. The amount of 14CO2 evolved from radioactive hymexazol treated soil increased with increasing temperature levels from 15C to 35C. Hymexazol was also degraded to CO2, acetoacetamide, and 5-methyl-2(3H)-oxazolone in the soil infested with Bacillus subtilis, Streptomyces griseus, Aspergillus niger, Arthrinium sp., or Penicillium sp. A certain portion of hymexazol and/or its metabolites were so tightly adsorbed by the soil that it could not be removed by extraction with 1N HCl and subsequent elution with 1N NaOH or methanol. Since acetoacetamide and 5-methyl-2(3H)-oxazolone were found to be less effective than hymexazol against Fusarium wilt of cucumber, the metabolism of hymexazol in soil can be considered as a detoxication step.View full abstractDownload PDF (990K) -
Tadao UI, Yoshihisa HOMMA1974 Volume 40 Issue 5 Pages 392-400
Published: December 25, 1974
Released on J-STAGE: April 03, 2009
JOURNAL FREE ACCESSThe decay of underground tissues of bean plants that had been inoculated with R. solani was induced by the removal of their shoot. R. solani and other fungi were isolated from lesions in the decying hypocotyls. The frequency of R. solani isolated from lesions decreased rapidly with increased decay of tissues, while that of other fungi increased. However, the remains of lesions from which no Rhizoctonia was isolated on agar plates, and the decomposed tissues of fibrous appearance from which the remains of lesions were removed, retained infectivity to bean hypocotyls. Histological studies of infected hypocotyls of shoot-removed plants showed the reactivation of inoculant fungus in lesions. When the inoculated plants become moribund, the pathogen grew from lesions into uninfected cortical tissues and penetrated vascular bundles directly or through endodermis. And monilioid cells of the fungus filled the thick walled vascular cells. The infected cortical layer decomposed in the early stage of decay, but the lesions consisting of sclerotia-like masses of hyphae were not decomposed. The decay of pith and vascular bundles proceeded slowly. They remained in the soil as fibrous plant residues containing monilioid cells of R. solani. The fungus in such remains of lesions and vascular cells persistes in soil at least until the next spring.View full abstractDownload PDF (2032K) -
Part I. The parasitisms of Pseudomonas eriobotryae phages and their morphologyAkira MORITA1974 Volume 40 Issue 5 Pages 401-411
Published: December 25, 1974
Released on J-STAGE: April 03, 2009
JOURNAL FREE ACCESSFifty one isolates of Pseudomonas eriobotryae phages were obtained from the cankerinfected loquat plant (Eriobotrya japonica Lind.) which were collected from various localities of loquat cultivation areas in Japan. These phages originated from the blightinfected bud, from the halo lesions of the leaf, and from the canker twigs were designated as EP1, EP2, and EP3 respectively.
The phage particles of both EP1 and EP2 are tadpole-shaped, and consist of a polyhedral head attached with long tail. EP1 phage has a head of 105nm in diameter with a tail of 170nm in length and 31nm in width, while EP2 phage consists of a head of 92nm in diameter with a tail of 118nm in length and 27nm in width. On the other hand, the shape of EP3 phage is much different from that of above two phages, and consists of a polyhedral head of 92nm in diameter with an extremely short tail of 17nm in length and 22nm in width.
Forty nine species (55 isolates) of pathogenic bacteria including 41 species of pseudomonads were tested on the susceptibility to each phages by means of the drop method. The host range of EP1 phage was strictly specific for P. eriobotryae, while others were non-specific. EP2 phage attacked P. ovalis and EP3 phage attacked P. striafaciens, P. mori, and P. flura, besides P. eriobotryae. Most of the isolates of P. mori were susceptible to EP3, but any kinds of P. mori phage did not attack P. eriobotryae isolates.
All the 123 isolates of P. eriobotryae were classified on the bases of their susceptibility to EP1, EP2, and EP3 phages as follows:
strain I; isolates which are susceptible to only EP1 but not to EP2 and EP3
strain II; isolates which are susceptible to only EP2 but not to EP1 and EP3
strain III; isolates which are susceptible to only EP3 but not to EP1 and EP2
strain IV; isolates which are susceptible to both EP2 and EP3 but not to EP1
strain V; isolates which are resistant to all of three phages
These strains seem to be different in their distribution patterns: the isolates belonging to strain I and III were widely distributed in Japan, and those belonging to strain II and IV were found to be distributed only in the intensivly cultivated area in Nagasaki Prefecture.View full abstractDownload PDF (2033K) -
Yukio HARADA, Kenzo SAWAMURA, Koki KONNO1974 Volume 40 Issue 5 Pages 412-418
Published: December 25, 1974
Released on J-STAGE: April 03, 2009
JOURNAL FREE ACCESSAn apothecium was found on apple leaves infected with blotch which had been overwintered out of doors on the ground. The ascospore grown on a culture medium produced Marssonina-type conidia. The ascospore caused typical symptoms of blotch when inoculated to apple leaves. The apothecium produced on overwintered diseased leaves is the perfect state of the causal fungus of blotch, Marssonina coronaria (Marssonina mali). After Nannfeldt's classification, the perfect state of the fungus belongs to the genus Diplocarpon of Dermateaceae, Helotiales. Morphological characters and host plants of the present fungus are distinct from those of the species known hitherto in this genus, hence Diplocarpon mali Y. Harada et K. Sawamura, sp. nov., is proposed for it. A possible role of the ascospores as primary inocula in spring to early summer is suggested.View full abstractDownload PDF (1368K) -
Tomizo OHGUCHI, Yoshio YAMASHITA, Yasuji ASADA1974 Volume 40 Issue 5 Pages 419-426
Published: December 25, 1974
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSLignin is formed in the cell wall of the downy mildew-infected Japanese radish root and peroxidase activity increases in the neibouring tissues. Attempts were made to study the functional role of this increased peroxidase activity in lignification in diseased tissues. The crude peroxidase prepared from the healthy tissue with ammonium sulfate precipitation and isoelectric point precipitation was fractionated into 11 fractions by cellulose column chromatography. The activity of the crude enzyme preparation increased gradually in response to the infection, reached a maximum 9 days after inoculation and then decreased. Elution profiles of peroxidase extracted from the root 9 days after inoculation showed that activities in acidic and neutral fractions apparently decreased while those of basic fractions increased. Polyacrylamide gel electrofocusing of the crude peroxidase preparation showed a decrease in activity of acidic isoperoxidases and an increase in activity of a part of basic and neutral isoperoxidases in the diseased tissue.View full abstractDownload PDF (1296K) -
Liberation of Cell Wall-Polysaccharides by the Action of Pectolytic Enzyme from Soft Rot PseudomonadAkira OHUCHI, Tokito TOMINAGA1974 Volume 40 Issue 5 Pages 427-432
Published: December 25, 1974
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSPreviously, we demonstrated histochemically that pectic substances in middle lamella and primary walls were specifically dissolved by the infection of soft rot pseudomonads. The present investigation was conducted to confirm the characteristics of carbohydrates liberated from cell wall materials during enzymatic maceration, using purified endo-PTE preparation from Pseudomonas marginalis (Brown) Stevens, N-6301 isolate. When radish fiber, instead of cell wall materials, was incubated with the purified enzyme at 30C in 0.033M tris-HCl buffer (pH 8.0), a large amount of carbohydrates were released rapidly in water-soluble state at the initial stage of reaction. The total yield of carbohydrates was about 27.5mg per 100mg of radish fiber at 90min. incubation, which corresponds to about 3 to 4 folds of non-enzymatic degradation. About 80% of these water-soluble carbohydrates were galacturonide residue, and about 95% of them were insoluble with 80%-EtOH. It is concluded, therefore, they mainly correspond to pectin-like substances.
EtOH-soluble carbohydrates contained two fractions, neutral sugars and oligogalacturonides. In neutral sugar, no visible change was observed between incubation mixture with enzyme and without enzyme. Oligogalacturonides specifically increased by the enzyme action, and the liberation of methyl esters was confirmed by paper chromatographic analysis. These results suggest that oligogalacturonide methyl esters are released from cell wall polysaccharides by trans-eliminative reaction of the enzyme used.View full abstractDownload PDF (799K) -
(I) Optical Microscopic Observations of Mycelia of Alternaria kikuchiana TanakaHiroshi ISHIZAKI, Kikuo MITSUOKA, Hitoshi KUNOH1974 Volume 40 Issue 5 Pages 433-438
Published: December 25, 1974
Released on J-STAGE: April 03, 2009
JOURNAL FREE ACCESSThe effects of polyoxin on mycelia of Alternaria kikuchiana Tanaka were observed with an optical microscope. The effects were roughly classified into four types, i) induction of characteristic bulbous structure at the hyphal tip and on the lateral hyphal wall, ii) induction of intrahyphae in relatively older hyphae, iii) acceleration of septation in relatively older hyphae, and iv) accleration of pigmentation in a whole mycelium. The above observations suggested that polyoxin might have several effects on this fungus in addition to the inhibition of chitin synthesis of the hyphal cell wall.View full abstractDownload PDF (1326K) -
Seiichi OKUDA, Norio NISHIMURA1974 Volume 40 Issue 5 Pages 439-451
Published: December 25, 1974
Released on J-STAGE: April 03, 2009
JOURNAL FREE ACCESSWitches' broom of Cryptotaenia japonica, a common vegetable in Japan, is widely distributed in Kanto area, and its occurrence is a serious problem in the culture of this vegetable. The symptoms consist of general yellowing and dwarfing of the plant, abnormal production of thin secondary shoots, and final death of the plant. Flower formation is considerably reduced, but no virescence or phyllody in floral parts is observed. Under the electron microscope, a large number of pleomorphic mycoplasmalike bodies were observed in sieve tubes, occasionally in the cytoplasm of phloem parenchyma cells, of the diseased plants, but these bodies were absent in the control healthy plants. These bodies were morphologically quite similar to those of mycoplasmalike organisms so far reported in plants. Thin filamentous forms were sometimes seen to protrude from these bodies. These forms were filled with electron transparent material, and netlike strands of nuclear material or ribosomelike granules could not be discerned. Of seven leafhopper species tested, Macrosteles orientalis was proved to transmit the disease in persistent manner. The incubation period in the leafhopper vector was 20∼26 days. The incubation period in the host plant was 20 days at 25∼30C, but it became longer as the temperature fell. No symptom developed on plants grown at 10∼15C. The disease was transmitted by the leafhopper to lettuce, garland chrysanthemum, and spinach. Electron microscopy of viruliferous M. orientalis revealed the presence of mycoplasmalike bodies in the cytoplasm of epitherial cells and muscle cells of midgut, and also of glandular cells of salivary gland. Their shape, size, and fine structure were very similar to those observed in plants. These results strongly suggest that a mycoplasmalike organism might be the causal agent of witches' broom of Cryptotaenia japonica.View full abstractDownload PDF (4457K) -
Mitsuo HIURA1974 Volume 40 Issue 5 Pages 452-453
Published: December 25, 1974
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSDownload PDF (177K) -
Rrozo YOKOSAWA, Shiro KUNINAGA, Michiaki TERANAKA1974 Volume 40 Issue 5 Pages 454-457
Published: December 25, 1974
Released on J-STAGE: April 03, 2009
JOURNAL FREE ACCESSDownload PDF (922K) -
Fujio ARAKI1974 Volume 40 Issue 5 Pages 458-460
Published: December 25, 1974
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSThe pathogenicity of Pyricularia oryzae and the inhibitory activity of fungicides against it with barley were very comparable to those of rice plant. The use of barley may be convenient for investigating the relation between infection behavior of fungus and disease development.View full abstractDownload PDF (663K) -
Hideki NAITO, Yukio KOSHIMIZU1974 Volume 40 Issue 5 Pages 461-463
Published: December 25, 1974
Released on J-STAGE: April 03, 2009
JOURNAL FREE ACCESSPartially emerged panicles were frequently observed in the paday fields where the Fusarium leaf spot was severe. Such symptoms in panicles were reproduced by injecting conidial suspension or extract of the fungus into the sheath cavity at the booting stage. Abortive grains also increased highly by the injection.View full abstractDownload PDF (730K) -
Seiichi OKUDA, Yoji DOI, Kiyoshi YORA1974 Volume 40 Issue 5 Pages 464-468
Published: December 25, 1974
Released on J-STAGE: April 03, 2009
JOURNAL FREE ACCESSChestnut yellow was dsescribed as a graft-transmissible virus disease by Shimada and Kouda (1954). Electron microscopy revealed the presence of possible causal mycoplasmalike bodies in sieve tubes of diseased chestnut leaves.View full abstractDownload PDF (1802K)
- |<
- <
- 1
- >
- >|