Japanese Journal of Phytopathology
Online ISSN : 1882-0484
Print ISSN : 0031-9473
ISSN-L : 0031-9473
Volume 58 , Issue 3
Showing 1-26 articles out of 26 articles from the selected issue
  • Chae Gun PHAE, Makoto SHODA, Nobuhiro KITA, Mituyuki NAKANO, Kinji USH ...
    1992 Volume 58 Issue 3 Pages 329-339
    Published: July 25, 1992
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    Antagonistic activities of Bacillus subtilis NB22 (NB22) isolated from a compost against plant pathogenic fungi and bacteria were examined in vitro. NB22 strongly suppressed not only the growth of 19 plant pathogenic fungi tested but also of 8 plant pathogenic bacteria. Its application to the biological control of crown and root rot and bacterial wilt of tomato caused by Fusarium oxysporum f.sp. radicis-lycopersici (FoR) and Pseudomonas solanacearum (Ps), respectively, was carried out in the field. When rice straw was immersed in cultural suspension of NB22 and then mixed into soils infested with FoR, the occurrence of crown and root rot of tomato was significantly reduced. In addition, when combined with steam sterilization, the suppressive effect was conspicuously enhanced and three to four times greater amount of yield was obtained compared with unsterilized control. Occurrence of bacterial wilt of tomato was also suppressed remarkably when the cultural suspension of NB22 was poured into heavily infested soils, and the percentage of dead plant with NB22 was one-third of the control. These results suggest that NB22 has a wide range of antifungal and antibacterial activities and can be used as a prominent agent to control these soilborne diseases of tomato.
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  • Kimiharu INAGAKI, Yoshihiro ISOMURA
    1992 Volume 58 Issue 3 Pages 340-346
    Published: July 25, 1992
    Released: February 19, 2009
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    Field isolates of Sclerotium oryzae-sativae Sawada were obtained from sheath blight-like lesions on maturing rice plants in 1983-1989 and were classified into strains according to anastomosis reactions (Hyphal fusion without cell death was observed in every pairing test between isolates within the same strain, but the fusion with cell death was observed in the test between isolates belong to different strains).Two hundred and eighteen and 245 isolates from two paddy fields differed in rice variety cultivated were assorted into 37 and 50 strains, respectively. Survey of presense of these strains in paddy fields for 6 years resulted that 55% of strains survived for one year and 22% of them were for 4-6 years. Strains distributing over a wide area in a field tended to survive for longer periods. In survival for 4-6 years, any strains did not remain at the same or neighbouring plot where those previously appeared. About 60% of strains were new ones which had not been detected in previous years, although the percentage differed in the year and the field. Three to 5 among 9-20 strains detected in each of two neighboring fields (ca. 20m apart) were common in the both fields in 1986 and 1987.
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  • Yasunori KOGA-BAN, Masanori SAKANISHI, Masato IKEGAMI
    1992 Volume 58 Issue 3 Pages 347-353
    Published: July 25, 1992
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    The changes in protein profiles of bean leaves (Phaseolus vulgaris) during the infection process of geminivirus, bean golden mosaic virus (BGMV), were studied using one- and two-dimensional polyacrylamide gel electrophoresis. After Coomassie Blue staining, no differences between BGMV- and mock-infected plants were observed in either one- or two-dimensional gel profiles. However, comparison of the protein profiles after incorporation of [35S] methionine showed that two specific polypeptides were induced by virus infection. One was the coat protein of BGMV and the other was a 24kDa protein assumed to be expressed by the host plant genome. During the progress of viral infection, the virus coat protein was strongly expressed at the late stage, while the 24kDa protein was expressed mainly at the early stage of infection. We suggest that this 24kDa protein plays an important role in BGMV infection.
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  • Seiji UEMATSU, Kousaku HIROTA, Toshimasa SHIRAISHI, Toshikatsu OOIZUMI ...
    1992 Volume 58 Issue 3 Pages 354-359
    Published: July 25, 1992
    Released: February 19, 2009
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    A fungus was isolated from rotted roots of bottle gourd stocks of collapsed watermelon plants in Chiba Prefecture Japan. The fungus was identified as Monosporascus cannonballus, which is known as one of the soilborne pathogens of melon. Pathogenicity of two isolates (CH86-1, CH86-2) was positive on bottle gourd stocks of watermelon plants as well as melon plants under greenhouse conditions. The disease was also found recently in Aichi and Gunma Prefectures.
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  • Tsuneo WATANABE
    1992 Volume 58 Issue 3 Pages 360-365
    Published: July 25, 1992
    Released: February 19, 2009
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    Soil samples from 28 locations (4-10 samples/Pref.) in South Kinki district were assayed for Pythium taxa by a trapping isolation method with cucumber seeds as a baiting substrate. One to seven taxa/sample (=location) were isolated or detected from 26 samples, but no Pythium was isolated from two samples from Wakayama prefecture. A total of 253 isolates were identified into 18 taxa including H-Zs, a provisional Pythium group with zoospore formation from hypha-like sporangia, but without sexual organs. Among these fungi, H-Zs was predominantly isolated from 20 samples, followed by P. sylvaticum, P. irregulare, P. ultimum, and P. aphanidermatum, all of which were isolated from 10-15 samples.
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  • Fumiyoshi FUKUMOTO, Hiroshi TOCHIHARA
    1992 Volume 58 Issue 3 Pages 366-372
    Published: July 25, 1992
    Released: February 19, 2009
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    The conditions of preservation of three freeze-dried cucumoviruses were investigated. From analysis of the viral virions using sucrose density gradient centrifugation, there were some differences in its profiles among freeze-dried preparations of three viruses. Freezedried preparations of purified cucumber mosaic virus gave a smaller peak at the same position of the sucrose gradients compared with the untreated control. Some of the virions of chrysanthemum mild mottle or peanut stunt viruses swelled and their sedimentation rate was slower than that of untreated viruses. In the preparations of the viruses supplemented with sucrose or inositol, the alteration of the virus particles was completely prevented. Also, the effect of various additives and the rate of the decrease of infectivity were similar when the freeze-dried preparations were stored at 65°C for assessing promptly the effect of additives during the preservation. Consequently, these facts suggest that the viruses, which belong to the same group and have similar stabilizing forces of virions, may exhibit similar characteristics during the preservation by freeze-drying or by additives and could be preserved under the same conditions.
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  • Yoshikuni NOMURA
    1992 Volume 58 Issue 3 Pages 373-379
    Published: July 25, 1992
    Released: February 19, 2009
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    Acute wilting of watermelons grafted on pumpkin rootstocks first occurred in plastic greenhouses in Kumamoto Prefecture in 1977. A fungus was isolated from the grafted tissues of the plant, being identified to be Fusarium oxysporum f. sp. lagenariae Matuo et Yamamoto, the pathogen of Fusarium wilt of bottle gourd (Lagenaria siceraria). This pathogen also infected Cucurbita ficifolia and C. maxima of pumpkin plants, although no infection was found on C. moschata, C. pepo and C. maxima×C. moschata. The symptoms of the infected C. ficifolia and C. maxima appeared as follows: the cotyledons became yellow and wilted at the early growing stage, and the foliage leaves soon wilted from the lower position after having become yellow. The growth of wilting plants gradually declined, followed by death finally. The roots of the diseased plant were poor and their root surface became brown. The pathogen was isolated from pieces of the stem tissues with browned vascular bundles in a high rate. This disease is proposed naming as ‘Fusarium wilt of pumpkin’.
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  • Samuel S. GNANAMANICKAM, Twng Wah MEW
    1992 Volume 58 Issue 3 Pages 380-385
    Published: July 25, 1992
    Released: February 19, 2009
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    Rice plant associated microorganisms both Pseudomonas spp. and Bacillus spp. were isolated and tested for antagonism against the rice blast fungus Pyricularia oryzae Cav. Field test of four selected strains in an upland rice farm in the Philippines afforded significant leaf blast reduction with rice var. UPLRi-5. Strain 7-14, identified as P. fluorescens was most effective. The crude extract prepared from this strain provided 70-100% inhibition of conidial germination at 1.0ppm. The antiblast extract also protected IR 50 rice seedlings from infection of P. oryzae. Evidence suggested that siderophore was unlikely to be involved in the mechanism of strain 7-14 in its antagonism against the rice blast fungus. In vitro test showed that inhibition of P. oryzae by strain 7-14 was not reversed by Fe amendments. Thus, the antiblast antibiotic, instead of siderophore production from Pseudomonas strain 7-14 protected rice seedlings from infection by P. oryzae.
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  • Naohiko HIROTA, Teruyoshi HASHIBA, Hozumi YOSHIDA, Toshio KIKUMOTO, Yo ...
    1992 Volume 58 Issue 3 Pages 386-392
    Published: July 25, 1992
    Released: February 19, 2009
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    Plasmid-like DNA (plDNA) was found in 10 out of 61 field isolates of Fusarium oxysporum. These 10 isolates were distributed among 6 formae speciales. Electron microscopic analysis revealed that all these plDNAs were linear molecules. The sizes of plDNAs found were varied from 1.9 to 8.0kb. The sequence homology among four 1.9kb plDNAs, pFOA, pFOL, pFOC and pFOR found in four different F. oxysporum formae speciales was examined by Southern blot analysis, using nick-translated plDNAs as probes. Considerable sequence homology was observed among pFOA, pFOL and pFOC DNA, but pFOR had no homology with three other 1.9kb plasmid DNAs. pFOM and pFOB DNAs of the sizes of 8.0 and 2.2kb, respectively, had no sequence homology with four plDNAs of 1.9kb.
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  • Shinya TSUDA, Kaoru HANADA, Soh HIDAKA, Yuzo MINOBE, Mitsuro KAMEYA-IW ...
    1992 Volume 58 Issue 3 Pages 393-404
    Published: July 25, 1992
    Released: February 19, 2009
    JOURNALS FREE ACCESS
    P isolate of tomato spotted wilt virus (TSWV-P) was purified by ultracentrifugation followed by metrizamide isopycnic density-gradient. Nucleocapsid purified after Triton X-100 treatment was disrupted with 1% SDS and analyzed by 1% agarose gel electrophoresis. RNA patterns were indistinguishable from those obtained from intact particles and both contained six single-stranded RNA species (ss1-ss6). When RNAs were extracted by phenol and precipitated by ethanol, three double-stranded RNA species (ds1-ds3) were appeared. The ds1, ds2 and ds3 was formed after annealing ss1 with ss2, ss3 with ss4 and ss5 with ss6, respectively. Glyoxal treatment rendered ds1-ds3 to three single-stranded RNA segments (L, M and S RNA). In Northern blot hybridization analyses using three glyoxalated single-stranded RNA segments as probes, S RNA hybridized with ss5 and ss6, in addition to ds3. M RNA hybridized with ss3, ss4 and ds2. L RNA also hybridized with ss1, ss2 and ds1. Moreover, S RNA segment, ss5, ss6 and ds3, hybridized with oligonu-cleotide probes of both polarities representing 3′ end sequence of S RNA segment and an internal part on N protein coding region. A probe of viral strand on N protein coding region, however, hybridized weakly to S RNA segment and seemed not to react to ss5. Interestingly, the amount of viral strand was about 4 times larger than the amount of viral complementary strand in S RNA species, as judged from reactivity of hybridization using strand-specific probes. These results indicate that three different-sized RNA segments are present in both viral and viral complementary strands in the nucleocapsid of TSWV.
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  • Hirofumi YOSHIOKA, Tomonori SHIRAISHI, Kimio NASU, Tetsuji YAMADA, Yuk ...
    1992 Volume 58 Issue 3 Pages 405-415
    Published: July 25, 1992
    Released: February 19, 2009
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    A pea pathogen, Mycosphaerella pinodes, secretes both an elicitor and a suppressor in its pycnospore germination fluid. The effects of the elicitor, the suppressor and orthovanadate, an inhibitor of P-type ATPase, on the activation of pathogenesis-related proteins such as endochitinase and β-1, 3-glucanase were examined. The elicitor induced the activation of these enzymes in pea, soybean and kidney bean. Such activation in 3 plant species tested was suppressed by the concomitant presence of 1mM orthovanadate with the elicitor. The suppressor, however, suppressed the activation in only pea plants but did not in nonhost plants of M. pinodes. These results suggest that the inhibition of the ATPase in plasma membranes highly correlates to the suppression of the activation of endochitinase and β-1, 3-glucanase.
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  • Noemi P. OROLAZA, Itsuo KAWAGUCHI, Takashi TSUGE, Noriyuki DOKE
    1992 Volume 58 Issue 3 Pages 411-415
    Published: July 25, 1992
    Released: February 19, 2009
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    The effect of AL-toxin produced by Alternaria alternata tomato pathotype on susceptible and resistant plants was investigated by employing a quantitative, simple and easy assay system using cultured roots of tomato. Root growth and root cell viability were examined by weighing and MTT [3-(4, 5-dimethylthiazol-2-yl)-2, 5-Biphenyl tetrazolium bromide] colorimetric assay, respectively. Cultured roots of susceptible cv. Mie First incubated in culture media containing different concentrations of AL-toxin I showed a detectable reduction and complete inhibition of the growth at toxin concentrations of 0.01 and 1μg/ml, respectively. The growth of cultured roots of resistant tomato cv. Saturn was significantly and completely reduced at toxin concentrations of 0.1 and 10μg/ml, respectively. When the root viability was determined by the colorimetric assay using MTT, the viability of susceptible cultivar was significantly reduced at a toxin concentration of 1μg/ml, two days after treatment, while reduction in the viability of resistant cultivar was not detected even at a toxin concentration of 10μg/ml. These results indicate that the use of cultured roots of tomato may contribute to a quantitative and qualitative determination for evaluating the host specific mode of action of AL-toxin.
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  • Motoyasu OCHI, Satoshi KASHIWAZAKI, Kazuyuki HIRATSUKA, Shigetou NAMBA ...
    1992 Volume 58 Issue 3 Pages 416-425
    Published: July 25, 1992
    Released: February 19, 2009
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    The partial sequence of the capillovirus potato virus T (PVT) RNA containing the 3′-terminal 2392 nucleotides, excluding the poly (A) tail, was determined from cloned cDNA. The sequence contains three open reading frames (ORFs) which encode putative proteins (in the 5′→3′ direction) of Mr>29, 000 (>29K; ORF 1), Mr 40, 451 (40K; ORF 2) and Mr 23, 596 (24K; ORF 3), followed by an untranslated region of 188 nucleotides upstream of the 3′ poly (A) tail. The 5′-proximal ORF 1 encodes a product with significant homologies to the C-terminal portions of the putative polymerase proteins of “alpha-like” supergroup of plant RNA viruses, including apple chlorotic leaf spot virus (ACLSV; closterovirus subgroup A), carlavirus, potexvirus and tymovirus. The PVT 24K protein shared several blocks of conserved amino acids with the coat proteins of filamentous viruses, i.e. ACLSV, beet yellows virus (BYV; closterovirus subgroup B), citrus tristeza virus (CTV; closterovirus subgroup C), potexvirus and carlavirus. The PVT 40K protein had homologies with putative movement proteins encoded by several plant viruses (e.g. ACLSV 50K protein). PVT and ACLSV showed a similar arrangement of three ORFs in the 3′-terminal region of their genomes. However, this arrangement differs significantly from that of BYV. The sequence represented here is the first report on the group capillovirus which was established recently. These results support a close relationship of PVT with ACLSV which is currently classified in the closterovirus subgroup A.
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  • Kinji USHIYAMA, Nobuhiro KITA, Kazuo SUYAMA, Nobuo AONO, Junko OGAWA, ...
    1992 Volume 58 Issue 3 Pages 426-430
    Published: July 25, 1992
    Released: February 19, 2009
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    An attempt was made at isolating the pathogenic bacterium, Pseudomonas syringae pv. actinidiae, on several kinds of actinidia plants for the purpose of identifying the infection source of the bacterial canker of kiwifruit (Actinidia deliciosa), an infection which is peculiar to Japan. Isolates, which were classified as P. syringae pv. actinidiae on the basis of serological characteristics using a monoclonal antibody against pathogenic agents, were isolated on six samples of A. arguta and A. kolomikta, This was out of a total of ninety samples collected from all over Japan. Twenty-two isolates within these causal agents showed some differences in pathogenicity but indicated a susceptibility reaction to actinidia plants. As the bacterial agent was also found to be distributed in Hokkaido, where kiwifruit plants are not found, it was concluded that the bacterial canker pathogen originated on the actinidia plants grown in Japan and was disseminated to kiwifruit vines.
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  • Pyoyun PARK, Sung-Suk LEE, Tohgo OHNO, Takashi TSUGE, Syoyo NISHIMURA
    1992 Volume 58 Issue 3 Pages 431-445
    Published: July 25, 1992
    Released: February 19, 2009
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    Plasma membrane modifications in AF-toxin I-treated susceptible strawberry leaves were similar to those in AK-toxin I-treated susceptible Japanese pear leaves, but the former was slightly different in ultrastructural features from the latter. The modifications due to AF-toxin I had the characteristic features in ultrastructure as follows: 1) the specific occurrence of small plasmalemmal invaginations at plasmodesmata, 2) the accumulation of scanty polysaccharide-components and a small amount of membranous fragments into the invaginated spaces between the cell walls and the plasma membranes, 3) the appearance of a moderate number of exocytotic Golgi vesicles, and 4) the relatively low incidence of the invaginations. The AF-toxin I-induced modifications were recognized as the slightly damaged type of plasma membrane modifications while the AK-toxin I-induced modifications as the severely damaged type. The results suggested that the effects of AF-toxin I on susceptible strawberry cells were different in some ways from those of AK-toxin I on susceptible Japanese pear cells. In addition, the leakage-sites of tissue-ions were examined in AF-toxin I-treated strawberry leaves, using both antimonate-fixation method and analytical electron microscopy. As the results, it was proved that Na and Mg ions were leaked from the plasma membranes in the vicinity of plasmodesmata at which the modifications specifically occurred in AF-toxin I-treated susceptible cells. This indicated that the slightly damaged type of plasma membrane modifications caused by AF-toxin I in susceptible strawberry leaves was closely associated with the electrolyte-leakage as well as the severely damaged type of plasma membrane modifications caused by AK-toxin I in susceptible Japanese pear leaves.
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  • Mamoru SATO, Fukumi SAKAI
    1992 Volume 58 Issue 3 Pages 446-451
    Published: July 25, 1992
    Released: February 19, 2009
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    Cell survival and plasmid stability in Pseudomonas syringae pv. mori Ni27 containing RSF1010 or its derivative recombinant plasmids (newly constructed pNIA1, pNIA2) were studied in soil and culture media. There was no apparent difference in survival-rate in sterile or non-sterile soil between plasmid-bearing strains and plasmid-free strain. Plasmid stability was strongly influenced by soil conditions (sterile or non-sterile/incubation temperature) and plasmid type in soil, and it was influenced by some culture conditions (temperature/slant or liquid/shaking or still/kind of medium) in culture media. Especially a low temperature (5°C) treatment was effective to lose plasmids in the broth still culture and in sterile soil.
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  • Yasuaki MORITA, Tsutomu ARIE, Shuichi KAWARABAYASHI, Kazuo SUYAMA, Shi ...
    1992 Volume 58 Issue 3 Pages 452-455
    Published: July 25, 1992
    Released: February 19, 2009
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  • Shu ISHIKURI, Hirokatsu UCHINO, Katsuichi KANZAWA
    1992 Volume 58 Issue 3 Pages 456-460
    Published: July 25, 1992
    Released: February 19, 2009
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  • Susumu UEDA, Takumi YOSHIZAWA
    1992 Volume 58 Issue 3 Pages 461-463
    Published: July 25, 1992
    Released: February 19, 2009
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    Total number of the trapped ascospores of Gibberella zeae in middle April was correlated with the degree of scab damage in wheat and barley in Ehime Prefecture from 1960 to 1990 (r=0.769, P<0.01). Field trials of fungicide application to the disease showed that the degree of scab damage was highly correlated with the degree of yield loss of the crops (r=0.977, P<0.01). Based on these results, the degree of yield loss, the degree of scab damage and the total number of the trapped ascospores corresponding to the economic injury level were estimated to be 5.77%. 2.65% and 18.52 spores, respectively.
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  • Seiichi OKUDA, Wei Quin WANG, Tomohide NATSUAKI, Michiaki TERANAKA
    1992 Volume 58 Issue 3 Pages 464-468
    Published: July 25, 1992
    Released: February 19, 2009
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    A new disease of tomato with yellow mosaic symptoms was found in Japan in 1983. A strain of alfalfa mosaic virus (AMV-T), proved to be the causal agent of the disease, was characterized comparing with another isolate of AMV from red clover (AMV-R). The two isolates varied in symptomatology in tomato, pea and petunia. Neither of the isolates affected soybean which is susceptible to many strains of AMV. AMV-T and AMV-R were slightly different from each other in polyacrylamide gel electrophoresis of double-stranded RNAs extracted from Nicotiana glutinosa plants infected with the two isolates, indicating that they had distinct electrophero-types. In agar gel diffusion using anti-AMV-T serum, a spur was formed, which was not formed in a test using anti-AMV-R serum, indicating that these two isolates were serologically related but antigenically different.
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  • Shinji KOTANI, Munenaga KURATA
    1992 Volume 58 Issue 3 Pages 469-472
    Published: July 25, 1992
    Released: February 19, 2009
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  • Katsushi YOKOYAMA, Tsutomu IJIRI, Yasuhisa FUJITA, Teruyoshi HASHIBA
    1992 Volume 58 Issue 3 Pages 473-475
    Published: July 25, 1992
    Released: February 19, 2009
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    A new method (HUMIDAS) for estimating relative humidity from data of AMeDAS (Automated Meteorological Data Aquisition System) was developed by multiple regression analysis. In this method, relative humidity (Y) for a 3-hr period is expressed as follows: Y=AX1+BX2+CX3+DX4+EX5+F. X1=temperature, X2=precipitation, X3=wind velocity, X4=shining hour and X5=range of temperature. The A-E values are regression coefficients and F is a constant. The relative humidity actually observed agreed well with the estimated values.
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  • Kinji USHIYAMA, Kazuo SUYAMA, Nobuhiro KITA, Nobuo AONO, Hiroshi FUJII
    1992 Volume 58 Issue 3 Pages 476-479
    Published: July 25, 1992
    Released: February 19, 2009
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    A new bacterial disease causing brown spot with yellow halo on the tara vine (Actinidia arguta) was found in 1988 in Kanagawa Prefecture. Two kinds of bacterium were isolated from these leaves. Bacterium isolated at high frequency produced brown spot with yellow halo on the leaves of A. arguta and canker symptoms on the kiwifruit. These symptoms were similar to naturally infected A. arguta and kiwifruit canker disease described by Serizawa et al. The second bacterium was not isolated so often and produced only brown spot without halo on the leaves of A. arguta. These bacteria were identified as Pseudomonas syringae pv. actinidiae and P.s. pv. syringae respectively on the basis of the bacteriological characteristics, and the reaction with a monoclonal antibody against P.s. pv. actinidiae and it's pathogenicity. This is first report that P.s. pv. actinidiae was isolated from wild grown A. arguta.
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  • Yoshihiko SUZUKI, Shinichi FUJI, Yoshiyuki TAKAHASHI, Makoto KOJIMA
    1992 Volume 58 Issue 3 Pages 480-484
    Published: July 25, 1992
    Released: February 19, 2009
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  • Daijiro HOSOKAWA, Minoru WATANABE
    1992 Volume 58 Issue 3 Pages 485-490
    Published: July 25, 1992
    Released: February 19, 2009
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  • Mitsuro KAMEYA-IWAKI, Hiroshi TOCHIHARA, Kaoru HANADA, Hiroaki TORIGOE
    1992 Volume 58 Issue 3 Pages 491-494
    Published: July 25, 1992
    Released: February 19, 2009
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    Attenuated isolates of watermelon mosaic virus 2 (WMV-2) were obtained by local lesion selection on Chenopodium quinoa after the treatments of partially purified materials of WMV-2 (W-80) with ultraviolet irradiation and nitrous acid. Squash, cucumber, muskmelon and watermelon seedlings inoculated with one of the isolates designated WI-9 remained symptomless, except mild symptoms on first true leaf, and showed protection to the later inoculation with virulent isolate of WMV-2 in greenhouse conditions.
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