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Volume 50 (1984)
- Issue 5 Pages 565-
- Issue 4 Pages 455-
- Issue 3 Pages 295-
- Issue 2 Pages 149-
- Issue 1 Pages 1-
Volume 50, Issue 2
Displaying 1-22 of 22 articles from this issue
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Toshiki SHIOMI, Miyoji SUGIURA1984 Volume 50 Issue 2 Pages 149-157
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSMycoplasmalike organisms (MLOs) transmitted by the leafhopper vector, Macrosteles orientalis Virbaste, were compared in host range and symptoms in test plants. Twelve MLO diseases from Japan, including Japanese honewort witches' broom, lettuce yellows, sickle hare's ear yellows, garland chrysanthemum witches' broom, water dropwort yellows, strawberry witches' broom, onion yellows, and carrot yellows were considered to be caused by the agents closely related each other. From the result of inoculation test with M. orientalis to the test plants including 20 species in 11 families, these MLO isolates were classified into three strains. Strain I infected Lactuca sativa, Callistephus chinensis, Chrysanthemum coronarium, Daucus carota, Apium graveolens, Spinacia oleracea, Allium cepa and others. Strain II infected Brassica rapa, Pisum sativum, Solanum melongena, Nicotiana glutinosa, and others, including the host plants of strain I. Strain III infected Lycopersion esculentum in addition to the host plants of strain II. Strain II and III did not infect Geranium nepalense which was a host plant of strain I.View full abstractDownload PDF (2429K) -
Fumiyoshi FUKUMOTO, Hiroshi TOCHIHARA1984 Volume 50 Issue 2 Pages 158-165
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSTo establish simple and practical methods for preservation of some Nepovirus and Comovirus, the effect of various additives was evaluated in connection with freezing and freeze-drying. The infectivity of purified tobacco ringspot virus (TRSV) suspended in 10mM potassium phosphate buffer pH 7.0, decreased gradually at -20C under frozen condition. The infectivity, however, was maintained at a high level for 41 months by addition of 0.5% peptone, 0.5% Na-glutamate, 3% (v/v) glycerol or 3% (v/v) dimethyl sulfoxide. By freeze-drying, the infectivity of TRSV in purified preparations decreased markedly and virus particles dissociated into RNA and empty protein shell. But, the addition of 1% glucose protected the virus conformation almost completely and the infectivity of such preparation was maintained at a high level. To obtain the results of protective effect of additives in freeze-drying preservation as quick as possible, the preparations were preserved at higher temperatures of 35C and 65C. The addition of 1% glucose or 0.5% lysine suppressed decrease of infectivity and protected the conformation of the virion from dissociation. Purified radish mosaic virus (RMV) showed the similar behaviour to TRSV on freezing and freeze-drying preservation. Frozen purified RMV lost considerably its infectivity during preservation for 41 months at -20C. However, the infectivity was maintained at a high level by addition of 0.5% peptone etc. By freeze-drying, purified RMV dissociated completely into RNA and empty protein shell or small granules, but the conformation was protected considerably by the addition of 1% glucose or 0.5% lysine etc., and the loss of the infectivity could be suppressed. Upon storage at 65C, freeze-dried preparation of the purified RMV lost its infectivity in several hours. But, the preparations supplied with 0.5% lysine maintained a high infectivity even for 2 days, showing the highest effect of protection. The infectivity of virus was deeply associated with maintenance of the virus conformation.View full abstractDownload PDF (1620K) -
Takashi UEDA, Hachiro OKU, Kazuo TOMITA, Kazuo SATO, Tomonori SHIRAISH ...1984 Volume 50 Issue 2 Pages 166-175
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSTwo toxic compounds were isolated from leaves of pine trees naturally infected by pine wood nematode, and identified as benzoic acid and pyrocatechol. From wood of naturally infected branches, three active compounds were isolated and determined as benzoic acid, 8-hydroxycarvotanacetone, and dihydroconiferyl alcohol. Benzoic acid and 8-hydroxycarvotanacetone caused very similar symptoms to those caused by inoculation with pine wood nematode.View full abstractDownload PDF (1054K) -
Takeo UCHIYAMA, Hiromi KATO, Masako ITO, Nagahiro OGASAWARA1984 Volume 50 Issue 2 Pages 176-188
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSAuthors recognized a decrease in morphogenetic potency of rice callus cultures by repeated subculturing. Based on this evidence, we investigated whether the rice callus cultures transferred from one to five times (F-callus) differed from that subcultured many times (M-callus) in its response to fungal infection. M-callus turned brown after 24 to 48hr by inoculation of Pyricularia oryzae and other plant pathogenic fungi. These fungi colonized favorably on M-callus. But growth of inoculated fungi on F-callus, with the exception of P. oryzae, was delayed in comparison with growth of fungi on M-callus. This evidence was based on the fact that F-callus formed the antimicrobial substances by the affection of fungi. But this activity was not so strong. However, there were no differences in growth of P. oryzae on both rice callus cultures. Quantity of polyphenols sligthly increased, but free o-diphenols were scarcely detected in both infected and noninfected rice callus cultures. Phenylalanine ammonia-lyase activity was increased in F-and M-callus by inoculation of P. oryzae and other fungi. No increase in respiration was observed in F-callus inoculated with fungi. Although tenuazonic acid caused the formation of necrotic spot on rice leaves which resembled of naturally infected one, callus surface was not changed at 50μg/ml of tenuazonic acid concentration, and callus growth was only inhibited with increasing concentration of it. We concluded from those results that R-gene actions in rice plant were not exhibited in rice callus cultures.View full abstractDownload PDF (1664K) -
(1). Suppression of Toxin Production from Germinating Spores under High Temperature StressTakashi TSUGE, Syoyo NISHIMURA1984 Volume 50 Issue 2 Pages 189-196
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSThe effect of thermal treatment on the pathogenicity of spores of Alternaria alternata Japanese pear pathotype was examined. When the virulent spores were subjected to a thermal treatment (e.g., at 50C for 10sec in water), they were not significantly inhibited their abilities of spore germination, elongation of germ tube and appressorium formation. However, they remarkably lost their pathogenicity to Japanese pear leaves susceptible to the black spot disease as well as productivity of host-specific AK-toxin during spore germination. Such an acquired effect on the pathogenicity and the toxin productivity was lost within about 24hr after the treatment. When the air-dried viable spores were continuosly exposed to hot summer temperatures for 13 days in field, the spores lost their pathogenicity and AK-toxin productivity without any visible damages on their germination ability. The above data suggest that certain thermal treatment of the spores of A. alternata Japanese pear pathotype causes to reduce their pathogenicity through the loss of AK-toxin productivity.View full abstractDownload PDF (773K) -
I. Occurrence of the Disease and the Characterization of the Causal BacteriumKouki OHTA, Koushi NISHIYAMA1984 Volume 50 Issue 2 Pages 197-204
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSCrown gall diseases of chrysanthemum, marguerite and rose were found in Shizuoka prefecture during 1974-1977. The causal bacteria were isolated from these infected plants and were tested for their pathogenicities and bacteriological characteristics. Twenty bacterial isolates were identified as Agrobacterium tumefaciens (Smith & Townsend 1907) Conn 1942 based on their pathogenicities and 70 cultural and physiological characteristics. These isolates were separated into two biovars by the difference in the following 15 physiological characteristics: 3-ketolactose production, kovac's oxidase, NaCl tolerance, maximum growth temperature, litmus milk, growth facter requirement, utilization of tartrate, malonate, and citrate, acid production from raffinose and erythritol, nitrate respiration, H2S production, arginine dihydrolase, and utilization of asparagine as a sole source of carbon and nitrogen. Six chrysanthemum, 6 marguerite and 4 rose isolates were classified into biovar 1, and other 4 rose isolates into biovar 2. DNA base composition was measured by the melting temperature (Tm) method. The Tm value of the isolates were in the range of 94.0-94.6C, and the GC contents were in the range of 58.2-59.7%.View full abstractDownload PDF (1443K) -
II. Pathogenicity and the Inoculum Potential of the Causal BacteriumKouki OHTA1984 Volume 50 Issue 2 Pages 205-210
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSPathogenicities of the crown gall bacteria isolated from chrysanthemum, marguerite and rose were investigated in relation of their biovars. These isolates were tested for their pathogenicities and inoculum potential on chrysanthemum, marguerite, rose, tomato and kidney bean. Chrysanthemum and marguerite isolates (biovar 1) were more pathogenic to their original host plants than to rose. Rose isolates (both biovar 1 and 2) were more pathogenic to rose than to chrysanthemum and marguerite. Tomato and kidney bean were also susceptible to any of the 3 isolates. Inoculation experiments with different inoculum doses of the causal bacteria showed that there were same differences in the inoculum potential of these 3 isolates.View full abstractDownload PDF (1108K) -
Takashi NAIKI, Kazuo TANAHASHI, Kohji KAGEYAMA1984 Volume 50 Issue 2 Pages 211-215
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSThe relationship between the frequency of root hair infection and clubroot severity caused by Plasmodiophora brassicae was studied using the European Clubroot Differential (ECD) hosts and 54 cultivars of 5 species of cruciferous plants which have been commonly cultivated in Japan. Root hair infection occurred in all test plants, but its frequency differed significantly among varieties and among cultivars even within the same species. Severe clubed roots occurred irrespective of the frequency of root hair infection. Although root hair infection is essential to induce club formation, the frequency of root hair infection was not closely related with the disease index representing subsequent disease severity.View full abstractDownload PDF (496K) -
Takashi NAIKI, Chizuko KAWAGUCHI, Hatiro IKEGAMI1984 Volume 50 Issue 2 Pages 216-220
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSThe root hair reinfection by Plasmodiophora brassicae occurred in healthy Chinese cabbage seedlings grown around the infected plant in which the fungus was present only in the zoosporangial stage. When reinfected seedling were transplanted again as an inoculum into the non-inoculated soil, root hairs in healthy seedlings became infected and the zoosporangial stage was developed. Our study revealed that the secondary zoospores released from zoosporangia in infected root hairs are able to reinfect healthy root hairs and repeat the zoosporangial stage in root hairs and epidermal cells.View full abstractDownload PDF (914K) -
Tadanori GOTO, Norio IIZUKA, Shoji KOMOCHI1984 Volume 50 Issue 2 Pages 221-228
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSAn attenuated virus isolate named Pa18 was successfully selected from the pepper plants in which the parent isolate P6 of tobacco mosaic virus pepper strain (TMV-P) has been inoculated and subjected to the subsequent heat treatment according to Holmes. The attenuated isolate Pa18 induced very mild symptoms on sweet pepper plants, and completely protected the plants from the infection by the parent isolate (P6) if the former was inoculated 10 days before the inoculation of the latter. The isolate Pa18, however, did not completely protect the plants from infection by tomato strain, yellow mosaic strain or another strain of TMV. The symptoms on sweet pepper caused by the isolated Pa18 remained mild throughout the growth period of the plant. The host range of the isolate Pa18 was found to be identical to that of the parent isolate (P6) which is infectious to 24 plant species belonging to 5 families. These host plants excepting Nicotiana megalosiphon, N. benthamiana and Physalis floridana failed to show symptoms or developed only faint mottling. Practical utilization of Pa18 for the control of the mosaic disease of sweet pepper was evaluated in the field. The growth of the plants infected with Pa18 was quite similar to that of the uninoculated control, while the growth of P6-infected plants was considerably poorer than that of Pa18-infected plants. The yield of the plants inoculated with TMV-P (P6) decreased as much as 36% of the uninoculated control, while that of Pa18-infected plants was almost the same as that of the uninoculated control. The yield of the plants inoculated with Pa18 and challenged by P6 decreased about 18% of that of the uninoculated plants, whereas the yield of the Pa18-infected plants increased 21.6% over that of plants inoculated with P6. In addition, the inoculation of the isolate Pa18 resulted in the suppression of mosaic symptoms on the fruit caused by the isolate P6. These results indicate that the attenuated isolate Pa18 may be effectively utilized for the control of mosaic disease caused by TMV-P in pepper plants.View full abstractDownload PDF (1464K) -
Yoshihisa HOMMA, Masayoshi ISHII1984 Volume 50 Issue 2 Pages 229-240
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSAnnular depressions and perforations in fungal cell walls were observed on hyphae and sclerotia of Rhizoctonia solani and on conidia of Cochliobolus miyabeanus following burial of these respective fungus propagules for 4 to 8 weeks in vegetable field soils obtained from various locations in Shikoku, Japan. The annular depressions and perforations were 1.0 to 5.5μm in diameter with 1 to 7 perforations per hyphal cell or conidium. Vampyrellid amoebae were isolated from soils and were estimated to number 2.0 to 33.0 per gram of soil. Trophozoites of the amoebae extended 500μm and more with extremely fine filopodia. Plasmotomy was common in large trophozoites before encystment. Digestive cysts were pale yellow, orbicular or elliptic and averaged 33.5×40.1μm in diameter. During excystment, trophozoites emerged through 10 to 20 holes 2.0 to 10.0μm in diameter in the cyst walls. Trophozoites engulfed hyphae in 5 to 20min after attaching to the fungal cell and emptied the contents of the cell within 40 to 90min for hyphae of R. solani and 60 to 120min for conidia of C. miyabeanus. Morphology of the trophozoites and cysts, the mode of encystment and excystment, and the feeding behaviour of the amoebae all match the descriptions for Arachnula impatiens Cienkowski.View full abstractDownload PDF (3252K) -
Nobuo MURATA, Hiroshi FUJII, Hitoshi MURATA1984 Volume 50 Issue 2 Pages 241-248
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSUnlike Erwinia chrysanthemi, E. amylovora or E. herbicola, many strains of which are compatible with F- and R-factors of enterobacteria, Erwinia carotovora hardly accepts these plasmids. This fact has delayed the development of genetic analysis in this important group of phytopathogenio bacteria. We introduced Mu-prophage into cultures of E. carotovora in the form of RP4::Mu and explored the possibility of using this plasmid for mobilizing chromosomal genes.RP4::Mucts61 (thermo-inducible Mu-prophage associated with RP4) was introduced from E. coli B228 into two strains of E. carotovora subsp. carotovora, and one strain each of E. carotovora subsp. atroseptica, E. chrysanthemi, and E. rubrifaciens. Thermal induction of the Mu-prophage in the transconjugants and the transfer of RP4::Mu from the transconjugants to other cultures of erwiniae were confirmed. Partial induction of Mu transconjugants at 37C showed that about a half of the colonies had lost the antibiotic resistance endowed by RP4. This treatment also induced an auxotroph requiring lysine. Mobilization of chromosomal markers during conjugation between donor cultures with partially induced Mu-prophage and recipient cultures harboring Mu-prophage was examined. In the matings between donors and recipients within E. carotovora subsp. carotovora, transfer of lysine synthesizing ability and of streptomycin resistance occurred at the rates of 3.4×10-9 to 4.2×10-7 and 1-1.2×10-8 per donor cell, respectively. The transfer of lysine synthesizing ability was also observed in the mating between donor E. chrysanthemi with RP4::Mu and a lysine auxotroph E. carotovora recipient. In most cases transconjugants receiving chromosomal markers were devoid of the antibiotic resistances conferred by the RP4 moiety of the plasmid.View full abstractDownload PDF (916K) -
Yoshiaki CHIKUO, Toshiya SUGIMOTO1984 Volume 50 Issue 2 Pages 249-254
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSInfection of sugar beet seed by Colletotrichum dematium f. spinaciae (sugar beet anthracnose pathogen) was examined. Severe damage was often seen on the seeds infected at early stage of flower development, from outset of flowering to its peak. Even in case of less heavier infection, seeds are fail to mature and die. If the seeds are able to mature, seed weight and germination rate is very low. Further, 80% of the seeds were found to carry the pathogen. The degree of the disease was different depending largely on sugar beet strains. The pathogen was isolated not only from seed cap and pericarp, but also from true seed inside the seed cap and pericarp. Thus polishing and/or processing of infected seed was not effective in reducing the rate of seed contamination.View full abstractDownload PDF (1148K) -
Mitsuro HYAKUMACHI, Tadao UI1984 Volume 50 Issue 2 Pages 255-262
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSDiseased isolates of Rhizoctonia solani (DIRS) which show abnormally slow growth in the early stage (less than half of the hyphal growth of healthy isolates during 5 days on potato dextrose agar) were isolated from the artificially inoculated sugarbeet field soil. DIRS were also obtained from the soil in the sugarbeet root-rot disease declined field. Among DIRS though the degree of disease is different, disease characteristics such as slow growth, hypal distortion, lysis of protoplasm, thin density of hypae in the apical part of the colony, and bad formation of sclerotia are commonly observed. Hyphal growth rate from the basal part of the colony of DIRS is better than that from the apical part of DIRS. DIRS could not be cured by incubation in the medium containing various amounts of streptomycin, ethydiumbromide, chloramphenicol, or cycloheximide. Disease agent(s) of DIRS could not be transferred to healthy isolates by hyphal anastomosis, and dsRNA also could not be detected from DIRS. Pathogenicity of DIRS varies from isolate to isolate, but is rather lower than that of healthy isolates. DIRS could be obtained in any of the R. solani anastomosis groups preserved by routine transfers. It has been suggested that if DIRS increase in field soil, inoculum potential becomes low as their low pathogenicity and slow growth, and consequently, disease is reduced and declines.View full abstractDownload PDF (1996K) -
Kiroku KOBAYASHI, Shyunichi INAMI, Takashi NAKAJIMA, Tadao UI1984 Volume 50 Issue 2 Pages 263-269
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSAntibacterial antibiotics, compound A and B, were isolated from sclerotia of R. solani AG-6 and identified them spectroscopically as the same pyron compounds as those from sclerotia of R. tuliparum. Of which, a compound inhibited the growth of many bacteria, but the other had no effect either on the fungi or on the bacteria.
Sclerotia of seven anastomosis groups of R. solani (AG-1, AG-2, AG-3, AG-4, AG-5, AG-6 and AG-BI) were checked the ability to produce compounds by TLC and GLC. Antibacterial antibiotic compounds were detected in sclerotia of all isolates of AG-6, but not of other anastomosis groups of R. solani so far tested.
From these results, it was found that there might be group specificity in the production of antibiotic pyron compounds among anastomosis groups of R. solani.View full abstractDownload PDF (1070K) -
Chikara MASUTA1984 Volume 50 Issue 2 Pages 270-272
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSA crude self-inhibitor of Botrytis cinerea was successfully extracted from highly concentrated spore suspension by ethylacetate (EtOAc). The inhibitory spot was shown at Rf 0.5-0.6 by the following procedure: after development with EtOAc: cyclohexane=1:1 (v/v), the thin-layer chromatogram was covered with water agar, and cellophane membrane was laid on the solid water agar, and then spores were spread over cellophane membrane. The ED50 of the crude extract determined from a plot of the percent inhibition of germination against the logarithm of concentration was 642ppm. The inhibitory activity was not lost after heating for 10min at 121C. The substance was permeable through cellophane membrane.View full abstractDownload PDF (853K) -
Taeko TAKEUCHI, Yuji NAGAI1984 Volume 50 Issue 2 Pages 273-275
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSMycelial growth and virulence of the dicarboximide-resistant strains of Botrytis cinerea isolated from greenhouses were compared with those of the sensitive strains after 6 month preservation at 10, 20, and 25C. The resistant strains were significantly inferior to sensitive ones in both mycelial growth on PSA media and virulence to excised kidney bean leaves. Sclerotia of the resistant strains buried in soil during summer were inferior to those of sensitive ones in viability.View full abstractDownload PDF (296K) -
Takahito NODA, Akira OHUCHI1984 Volume 50 Issue 2 Pages 276-277
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSIn this paper, the authors report a new finding that an isolate of Xanthomonas campestris pv. oryzae became unexpectedly avirulent to a rice variety Kinmaze and some others. This isolate is the variant derived from Q6809 belonging to bacterial group III of X. campestris pv. oryzae. It was originally virulent to rice varieties belonging to Kinmaze, Kogyoku and Rantai Emas group and to IR 8, but has lost its virulence to japonica type rice varieties including Kinmaze group through successive transfers on artificial media. The virulence pattern of the variant is quite different from that of any of the already known bacterial groups.View full abstractDownload PDF (265K) -
Masako KATAGIRI, Yasuhiko UESUGI1984 Volume 50 Issue 2 Pages 278-280
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSDownload PDF (230K) -
Mitsuro HYAKUMACHI, Yoshihisa HOMMA, Tadao UI1984 Volume 50 Issue 2 Pages 281-285
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSDamping-off disease of radish seedlings declined in the soil into which normal field isolate 1271 belonging to Rhizoctonia solani AG-4 was repeatedly (3 times or more) inoculated. Diseased isolates which show abnormally slow growth were isolated from this disease declined soil. By incubating normal and diseased isolates in pair, diseased agent(s) of diseased isolate could be transferred to isolate 1271 by hyphal anastomosis, but not to other isolates of AG-4 and AG-2-2. This shows transmission of diseased agent is isolate-specific. Diseased isolates produce acidific substances, particularly oxalic acid. In comparison with that of isolate 1271, pathogenicity of diseased isolates is extremely low, though it varies from high to low. Using as inocula mixtures of isolate 1271 and diseased isolates, damping-off disease of radish seedlings decreased when inoculum of isolate 1271 was low, and cross protection could be seen among isolates.View full abstractDownload PDF (1570K) -
Takeshi TANIGUCHI, Emma S. DATA, Oliver J. BURDEN, Ikuzo URITANI, Mari ...1984 Volume 50 Issue 2 Pages 286-288
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSDownload PDF (1213K) -
Tokiya SHIMIZU, Takio ICHITANI1984 Volume 50 Issue 2 Pages 289-293
Published: April 25, 1984
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSDownload PDF (1530K)
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