• Research in Plant Disease
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• v.14 no.2
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• pp.79-84
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• 2008

A wilt disease on lettuce was observed in 2006 and 2007 in commercial plastic house at main production areas of lettuce in Icheon, Yongin and Goyang of Gyeonggi Province. The disease was characterized by the wilting of lower leaves, accompanied by stunting symptoms of the whole plants. Old affected stems showed the black streak in the vascular system. The pathogen, Fusarium oxysporum f. sp. lactucae was isolated from stems and roots of diseased plants. Isolated pathogen also produced the microconidia and macroconidia with chlamydospores on carnation leaf agar medium. The pathogen easily invaded and made many chlamydospores on the roots of lettuce and also made dark streaking through the vascular in the lettuce stems. The density of Fusarium sp. in the severely diseased field soil was more higher populations than that in the healthy and less diseased field soil. The minimum population of pathogen would be above $10^3$cfu/g soil to induce the Fusarium wilt on lettuce in plastic house. The results of pathogenicity test showed 'Sunpung' and 'Mipungpochap' was high susceptible to Fusarium pathogen isolates while some cultivar 'Mihongjeokchukmyeon' and 'Jinjachukmyeon' showed moderate resistance. Disease development for some lettuce was related to treated temperature, so the symptom was more severe above $25^{\circ}C$. Selection of appropriate lettuce cultivar and planting time should be related for the successful control of Fusarium wilt.

• Korean journal of applied entomology
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• v.19 no.4 s.45
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• pp.193-198
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• 1980

This paper deals with the studies on the occurence of a new virus disease of sesame and the identification of the causal virus. The virus disease of sesame has been regarded as a widespread disease in the sesame-growing areas in the southern part of Korea. The disease was found to be caused by watermelon mosaic virus (WMV). During the years since 1978, stunting of sesame plants, with yellow mosaic, necrotic spot, and malformation, were collected from 17 different places. Virus isolates from 27 out of 32 samples were identified as WMV. Natural infection of squash, pumpkin, cucumber, and watermelon by WMV as well as sesame was proved. The virus is inactivated at temperatures of 55 to $60^{\circ}C$, at dilution of $10^{-3}\;to\;10^{-4}$, and in the aging of 10 to 14 days at about $20^{\circ}C$. Sesame, Chenopodium amaranticelor, pea, bean, as well as many plants of the Cucurbitaceae, are susceptible to the sesame-isolates of WMV. In negatively stained preparations, particles of the virus appear under the electron microscope as flexible filaments of about $750\~800nm$ in length. Cylindrical inclusions and virus particles were found in the cytoplasm of mesophyll cells by ultra-thin sections of WMV infected tissues.

• Korean Journal Plant Pathology
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• v.3 no.3
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• pp.223-235
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• 1987

Samples showing yellow mosaic symptom of Lilium spp. with necrotic fleck, stunting, malformation, and colour breaking were collected from lily-growing areas in the southern part of Korea. Two viruses were distinguished under a electron microscope and their host range, serological reaction, stability in sap, type of aphid transmission, and relations with cells and tissues were examined. Broad bean wilt virus (BBWV) was transmitted by sap-inoculation to 23 plant species in 8 families and by the aphid, Myzus persicae. This virus was inactivated after 10 min at 70C, at dilution of $10^{-3}$, and after 6 days at about 20C. Electron microscopic examination of purified preparation showed that the virus is spherical particle of 28nm in diameter. The virus reacted positively with BBWV-antiserum in agar gel diffusion test. In ultrathin sections of BBWV infected tissues, large aggregates or crystalline array of virus particles and vesicular body were found in the cytoplasm, vacuole, and nucleus of mesophyll cells. Cucumber mosaic virus (CMV) was transmitted by sap-inoculation. Electron microscopic examination of its purified preparation showed spherical particles of 30nm in diameter. The virus reacted positively with CMV-Y strain-antiserum in agar gel diffusion test. In ultrathin sections of CMV infected tissues, crystalline array of virus particles were found in the vacuole and a large number 0f virus particles were found in the cytoplasm and the plasmodesmata of mesophyll cells. When each of these viruses was retransmitted to Lilium tigrinum. L. concolor, and L. auratum, BBWV induced slight symtoms and colour breaking, but CMV induced yellowing mosaic or necrotic fleck.

• Research in Plant Disease
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• v.24 no.1
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• pp.75-80
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• 2018

From 2014 to 2016, Fusarium wilt disease was found on fassionfruit in Iksan and Jeju, Korea. Symptoms included wilting of foliage, drying and withering of leaves, and stunting of the plants. The infected plants eventually died during growth. Colonies on potato dextrose agar were pinkish white, and felted with cottony and aerial mycelia with 35 mm after one week. Macroconidia were falcate to almost straight, thin-walled and usually 2-3 septate. Microconidia were usually formed on monophialides of the hyphae and were hyaline, smooth, oval to ellipsoidal, aseptate or medianly 1-septate, very occasionally 2-septate, slightly constricted at the septa, $3-12{\times}2.5-6{\mu}m$. On the basis of the morphological characteristics and phylogenetic analyses of two molecular markers, internal transcribed spacer rDNA and translation elongation factor $1{\alpha}$, the fungus was identified as Fusarium oxysporum. Pathogenicity of a representative isolate was proved by artificial inoculation, fulfilling Koch's postulates. To our knowledge, this is the first report on the occurrence of F. oxysporum on fassionfruit in Korea.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.4
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• pp.607-612
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• 2009

The malignant tumor in childhood is one of the main causes of children s death due to disease. The traditional treatment for the malignancy is known for the radiation therapy and the chemical therapy or both. However, the treatments tend to induce intraoral complications. Different from adults, almost all children on cancer therapy are expected to have dental complications, because their permanent teeth are on the developmental stage. The degree of dental complication depends on the patient's age, type of chemical and other factors-radiation dose and frequency. In this report, 3 children who had experienced the anti-cancer therapy on their age between 1 and 4 years were selected and dental complications were examined. The children have chance for the various oral complications including the developmental problems such as agenesis, microdontia and hypoplasia of the teeth. Therefore, it's important to understand the side-effects of anticancer therapy during the permanent teeth had been developmental stage in young patients. Also, oral health care specialists, including pediatric and hospital dentist can support the oncology team by providing basic oral care, implementing oral care protocols, delivering emergency dental treatment undergoing anticancer treatment.

• Korean Journal of Weed Science
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• v.16 no.1
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• pp.28-35
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• 1996

Tetrapion(2,2,3,3-tetrafluoropropionate sodium) has commonly been used for reed(Phragmites communis Trin.) control in uncultivated areas, especially in Japan. As an attempt to establish the screening system for selective herbicide controlling reed, tetrapion was tested as a standard herbicide to various weeds and crops including rice in a greenhouse. Symptoms of yellowing, twisting, stunting, and necrosis were observed in the herbicide-treated plants. The herbicide caused a severe damage on all crops examined, except cotton. Both direct seeded and transplanted rice were also sensitive to the herbicide. Its herbicidal activity was generally higher on grass weeds than on broadleaf weeds. It had a higher herbicidal activity with preemergence treatment than with postemergence treatment. In addition, field and greenhouse experiments were conducted to examine the effect of the herbicide on reed control. Its effect varied with the soil type of the treated field and the growth stage of reed. A relatively high dosage of the herbicide was required to control reed. It had an almost same effect on fairygrass(Miscanthus sinensis Anderss) as on reed. However, reed grown in a greenhouse was effectively controlled by the herbicide, having more effect with preemergence treatment than with postemergence treatment as observed in other plants treated with the herbicide. In conclusion, tetrapion has a great potential as a standard herbicide during the herbicide screening for selective reed control.

• Journal of Bio-Environment Control
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• v.12 no.3
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• pp.139-146
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• 2003

This study was conducted to investigate the effects on the over-growth inhibition of fruit vegetables (tomato, cucumber, and hot pepper) seedling by the treatment of triazole-typechemicals and to select the most effective chemicals for the over-growth inhibition, and to investigate suitabla concentration treatment and times of the newly selected chemical. The triazole-type chemicals inhibited stem height more, the more the concentration is increased in any crops. The diniconazole showed the highest dwarfing ration, and the tebuconazole and hexaconazole are also good for dwarfing ratio. The diniconazole decreased the plant height of cucumber, tomato, and hot pepper as the concentration is increased. In cucumber, thc dwarfing ratio was 30% in the 5 mg${\cdot}L^{-1}$ treatment, and was 60% in thc l00 mg${\cdot}L^{-1}$ treatment. In tomato and hot pepper, the dwarfing ratio was 30% in the 25 mg${\cdot}L^{-1}$ treatment in any times. In diniconazole treatment, the cucumber and tomato should have 5 mg${\cdot}L^{-1}$ at the lst growth stage and the hot pepper should have 5 mg${\cdot}L^{-1}$ at the 2nd growth stage to obtain good seedlings.

• Korean journal of applied entomology
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• v.23 no.1 s.58
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• pp.15-21
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• 1984

The virus infecting French bean (Phaseolus vulgaris L.) was identified as Bean Common Mosaic Virus(BCMV) based on the host range, symptomatology, serology, morphology of virus particles and inclusion bodies. Isolates of BCMV were obtained from seeds of P. vulgaris collected at Suweon, Jangsu and Jinju in Korea. French bean produced vein clearing, mosaic, stunting and leaf curling. Symptom of Chenopodium quinoa was local lesions on the inoculated leaves, not on the upper leaves. The electron micrograph of the virus from French bean was flexuous approximately 750nm in length. Cylindrical and pinwheel cytoplasmic inclusion bodies were observed in French bean leaf infected by BCMV. BCMV from the French bean was transmitted through seed and green peach aphid, Myzus persicae. The thermal inactivation point was $55\~60^{\circ}C$, dilution end point was $10^{-3}\~10^{-5}$ and longevity in vitro was $2\~3$ days for BCMV from French bean. The isolates of BCMV reacted positively against BCMV antiserum. The extract of BCMV infected bean leaves, Azukibean mosaic virus (AZMV) and Cowpea aphid borne mosaic virus(CaMV) also reacted with BCMV antiserum, however, BCMV and CaMV showed the spur in agar gel diffusion test.

• Korean journal of applied entomology
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• v.2
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• pp.47-54
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• 1963

The chestnut gall wasp, Dryocosmus kuriphilus $Y^{ASUMATSU}$, has been recently distributed and chestnut trees have teen seriously damaged by this insects in Korea. However, this insect pest has not been investigated in Korea. This paper gives an account of field and Laboratory observations on the seasonal occurrence and the life history of the chestnut gall wasp, and the damage of the chestnut trees by. its insects. This study was carried out at Chungchungpukdo, Kangwon-do and Kyungi-do in Korea, from 1961 to 1963, inclusive. 1. The Chestnut gall wasp (Dryocosmus kuriphilus $Y^{ASUMATSU}$) has one generathion per year and females are only known. 2. The adult wasps were observed from late June to late July with peak of wasp emergence about early and middle July. Most of new adult wasps were coming out from, the galls in the morning rather than the afternoon. 3. Each wasp produced auerage 198.5 eggs and about 4.89 eggs was observed in each bud of the chestnut tree. 4, The egg period of wasps was about 30 days and they were hatching from July to August. 5. The larval period of wasps were from middle of August to middle of next June and pupation took places about early June to middle of July. 6. The adult wasps were ovipositing into the buds and from early May next year, galls were growing. They caused stunting of growth and no fruiting or dying of the chestnut tries. 7. The first observation of the wasp was made at Chaechun of Chungchung-pukdo in 1958. Up to 1963 this insects are distributed in Kangwon-do, Kyunggi-do, north part of Chungchung-pukdo and north part of Kyungsangpukdo

• The Korean Journal of Mycology
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• v.45 no.1
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• pp.74-82
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• 2017

Lisianthus (Eustoma grandiflorum) is a flowering ornamental plant used widely in Korea. In 2015, wilting, damping-off, stunting, and root rot symptoms were observed in lisianthus plants of Yeoju and Gimhae, Korea. Affected seedlings appeared yellow and showed poor development of root systems in the field and in nursery boxes. Furthermore, affected plants were yellow, stunted, and died at approximately 2-3 months after transplanting. Fusarium species were consistently isolated from the basal stems of diseased plants. Nine isolates were identified as Fusarium solani based on morphological characteristics. Macroconidia of isolates were relatively wide, straight-to-slightly curved, and microconidia formed in false heads on long monophialides. Abundant chlamydospores were produced at the middle or tips of hyphae. To confirm this identification, a molecular analysis of the translation elongation factor 1 alpha (TEF) and RNA polymerase II subunit (RPB2) genes was conducted. The sequences of TEF and RPB2 showed 99.2-99.9% and 98.0-98.1% similarity, respectively, to those of reference F. solani strains in NCBI GenBank. Pathogenicity was tested using root dipping inoculation of healthy lisianthus seedlings. Symptoms were observed within 7 days of inoculation only in inoculated plants. This is the first report of F. solani causing Fusarium root rot on lisianthus in Korea.