• 식물병연구
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• 제28권2호
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• pp.108-111
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• 2022

In December 2020, stem and leaf rot symptoms in small-fruited tomato (Solanum lycopersicum) plants were observed in a farmer's vinyl greenhouse located in Pyeongtaek, Gyeonggi Province, Korea. The incidence of diseased plants in the vinyl greenhouse was 2-6%. Seven single-spore isolates of Phoma sp. were obtained from the diseased stems and leaves. All the isolates were identified as Boeremia linicola based on the cultural, morphological and molecular characteristics. Two isolates of B. linicola were tested for pathogenicity on stems and leaves of small-fruited tomato and large-fruited tomato using artificial inoculation. All the tested isolates caused stem and leaf rot symptoms in the inoculated plants. The symptoms were similar to those observed in plants from the vinyl greenhouse investigated. This is the first report of B. linicola causing stem and leaf rot in tomato.

• 생명과학회지
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• 제14권4호
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• pp.689-695
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• 2004

2003년 11월 경상남도 부림면 신반리의 결구상추 재배 플라스틱 하우스내에서 늦가을부터 밑둥썩음병이 발생하여 수확기인 11월에 평균 5.3%의 발병율이 조사되었다. 이는 비교적 낮은 수치이나, 2차적으로 균핵병과 잿빛곰팡이병이 유발되어 큰 경제적 피해를 야기하였다. 이때의 병징은 아랫잎의 밑둥 부위에 수침상의 원형 내지 타원형의 담갈색 또는 갈색점무늬가 나타나고 진전되면 윗잎쪽으로 병반이 부정형으로 크게 확대되어 결국 잎이 무르게 썩고 누렇게 변하며 종이처럼 말라죽는 증상이 관찰되었다. 이에, 밑둥썩음병이 발생한 지역의 병든 식물체와 토양으로부터 병원균을 분리하였으며 이 중 병원성이 가장 강한 PY-1 균주가 Rhizoctonia solani AG1 (IB)로 동정되었다. 균사생육 최적온도는 25∼30$^{\circ}C였으며, 병원성 검정을 위해 가장 효과적인 접종원으로 검정 방법이 용이하면서도 효율적인 균사조각 부유액 접종원을 생육상내 폿트 검정용으로 선발하였고, 토양내 부생적 착생을 위한 플라스틱 하우스내 토경 재배 검정용으로는 WRSP배지 접종원을 선발하였다. 또한, 선발된 각 접종원의 최적 처리농도 및 처리량에서는 각각 균사조각 부유액 접종원의 경우, 평균 주당 51.1%의 발병도를 보인 $A_{550}$=1.0농도를 가장 적합한 처리 농도로 선발하였으며, WRSP 배지 접종원의 처리량 비교에서는 평균 주당 61.6%의 발병도를 보인 40 $m\ell$를 최적 처리량으로 선발하였다.

• 식물병과 농업
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• 제5권1호
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• pp.34-40
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• 1999

The virus infection rates and disease symptoms of three major citrus viruses, citrus tristeza virus (CTV), satsuma dwarf virus (SDV), and citrus tatter leaf virus (CTLV), were investigated at 35 citrus orchards in Cheju Island from 1995. The infection rates of CTV, SDV, and CTLV were 69.8%, 8.6%, and 9.3%, respectively. However, depending on cultivars there were significant differences in the infection rates. The infection rates of CTV were highest in early satsuma mandarin (Citrusunshiu) with 80.9% and lowest in very early satsuma mandarin with 51.9%. In SDV, the highest was in very early stasuma mandarin with 23.1% and the lowest was in early satsuma mandarin with 6.3%. And the highest infection rate in very early satsuma mandarin with 17.9% and the lowest in tangors with 7.3% in CTLV. The symptoms of virus-infected citrus were very diverse; small and abnormal shape of fruits, abnormal leaves such as narrow boat and small spoon shapes of leaves, stem-pitting on the twig, bud-union crease and swelling of the graft part, reduction of the plant vigor and poor yields.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.107.2-108
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• 2003

Viral disease symptoms were investigated in the field grown Longiflorum hybrid cultivars, and the damages caused by infection with Lily mottle virus (LMoV) and Cucumber mosaic virus (CMV) were assessed by comparing growth of plants produced from seeds of Longiflorum hybrid cultivar both infected by artificial inoculation and free from infection with theses viruses. Dominant symptom caused by spotaneous infection with LMoV and CMV in the field was mottle combined with chlorotic stripe on leaves. LMoV developed brownish necrotic lesion on floral leaves. The incidence of viral disease by mixed infection with LMoV, CMV or Lily symptomless virus (LSV) in the filed grown Longiflorum hybrid cultivar, cultivated for more than 6 years, was 80 to 84 percent. In comparison with virus-free plants, plants doubly infected with CMV and LMoV by artificial inoculation decreased stem length by 14 percent and fresh weight by 38 percent. In conclusion, flower quality and the stem length of Longiflorum hybrid cultivar were affected by LMoV and CMV infection.

• 식물병과 농업
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• 제5권2호
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• pp.77-83
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• 1999

In 1997 surveys 82 out of 180 crucifer fields were infected with clubroot disease in a range of 1-100% of diseased plants and among crucifier crops Chinese cabbage was the most severe, In cropping systems Chinese cabbage-monocropping of Chinese cabbage-radish were found to be most common in major Chinese cabbage production areas. Welsh onion squash or paddy rice were also planted between cropping of Chinese cabbage. Paddy fields converted to upland were lowered in incidence of clubroot disease and fields with loam to silty loam soil were more severe in disease than those with sandy soil. Soil pH and organic contents were nor related to clubroot disease severity. Soil fauua such as total fungi bacteria actinomyces Pseudomonads and Bascillus were not correlated with severity of the disease. Root rall development on Chinese cabbage seedlings was initifially observed under a microscope 13 days after inoculation with Plasmodiophora brassicae but 18 days by naked eyes after inoculation. Root galls were formed mostly around collar roots and gradually spread to main root lateral roots and secondary root branches. Root galls started to enlarge greatly in size and weight from 23 days after inoculation. Chinese cabbage plants at mid-growth stage with root gall development were reduced to 1/2 of that of healthy plants in number of leaves 1/4-1/5 in above ground fresh weight 1/6 in root length but increased to 3 times in diameter of collar root. Diseased plants had little root hairs. Diseased Chinese cabbage plants at harvest were reduced by 9,1-11.8% in head weight compared to healthy plants a positive correlation was observed between root and head weight but those relationships were rot found in the diseased plants.

• 한국식물병리학회지
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• 제14권2호
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• pp.188-190
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• 1998

Fusarium wilt of lisianthus occurred severely throughout all cultivation areas, especially in alpoine areas during summer season and the disease incidence was 5 to 30 percent in Korea. The major symptoms of the disease were wilt with chlorosis and water deficiency, stunted plants and scorched leaves. Severe symptoms appeared just after high temperature period around late August in Daekwallyong area. Whit and pale red colored mycelia were developed on stems of infected plants near the soil surface. The causal organism of Fusarium wilt of lisianthus was isolated and identified as Fusarium oxysporum f. sp. eustomae on the basis of pathogenic and cultural characteristics. The causal organism was reisolated from all infected and inoculated stems of plants. This is the first report referring to F. oxysporum f. sp. eustomae of lisianthus in Korea.

• 식물병연구
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• 제13권2호
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• pp.75-81
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• 2007

전국 52개 지역에서 2002년, 2004년에서 2006년, 4년 간 고추 바이러스 이병물을 채집하여 바이러스 감염양상을 조사하였다. 감염된 바이러스 종류는 Cucumber mosaic virus(CMV), Pepper mottle virus(PepMoV), Pepper mild mottle virus(PMMoV), Broad bean wilt virus 2(BBWV2), Tobacco mild green mosaic virus(TMGMV), Tomato spotted wilt virus(TSWV) 6종이었다. CMV, PepMoV PMMoV와 BBWV2의 발생률은 각각 29.4%, 13.6%, 14.3%, 25.6%이었다. TMGMV와 TSWV의 발생률은 1.0%로 매우 낮았다. 2002년과 2004년의 CMV 발생률은 53.3%와 34.2%로 가장 높았으나 2005년과 2006년에는 18.2%와 11.9%로 감소하였다. BBWV2의 발생률은 2002년에 1.3%, 2004년에 1.8%로 낮았으나, 2005년에 41.3%, 2006년에 58.2%로 크게 증가하였다. CMV+BBWV2의 발생률은 2002년에 0.0%, 2004년에 2.1%이었으나 2005년과 2006년에 각각 33.3%와 83.2% 증가하여 BBWV2의 단독감염과 함께 복합감염에서도 급격히 증가하였고 CMV+BBWV2+PepMoV의 삼중 복합감염률은 평균 6.4%이었다. CMV는 고추 잎에 심한 모자이크병징, BBWV2는 원형반점 병징을 일으키며, CMV와 BBWV2의 복합감염 경우에는 퇴록병징을 일으켰다. TSWV는 고추 잎과 과일에 전형적인 다중 원형반점을 일으켰다.

• Mycobiology
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• 제51권5호
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• pp.313-319
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• 2023

During disease surveys of Angelica acutiloba plants in Korea, leaf spot symptoms were observed in a field in Andong in July 2019, and stem rot symptoms in vinyl greenhouses in Yangpyeong in April 2020. Incidence of leaf spot and stem rot of the plants ranged from 10 to 20% and 5 to 30%, respectively. Morphological and cultural characteristics of fungal isolates from the leaf spot and stem rot symptoms fitted into those of the genus Phoma. Molecular phylogenetic analyses of two single-spore isolates from the symptoms using concatenated sequences of LSU, ITS, TUB2, and RPB2 genes authenticated an independent cluster from other Didymella (anamorph: Phoma) species. Moreover, the isolates showed different morphological and cultural characteristics in comparison to closely related Didymella species. These discoveries confirmed the novelty of the isolates. Pathogenicity of the novel Didymella species isolates was substantiated on leaves and stems of A. acutiloba through artificial inoculation. Thus, this study reveals that Didymella acutilobae sp. nov. causes leaf spot and stem rot in Angelica acutiloba.

• 식물병연구
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• 제20권3호
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• pp.211-215
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• 2014

본 연구는 파인 오일과 수산화동의 혼용에 의한 고추의 세균성 점무늬병과 탄저병에 대한 방제 효과를 구명하고자 수행하였다. 세균성 점무늬병에 대한 방제 효과는 파인 오일만 단독 처리한 경우 발병엽률 59.6%와 방제 효과 28.9%로 나타났지만 파인 오일과 수산화동을 4:1로 혼용 처리하였을 때 발병엽률 20.0%와 방제효과 76.1%로 가장 효과적이었다. 탄저병에 대한 방제 효과는 파인 오일만 단독 처리한 경우 발병률 79.1%와 방제 효과 7.4%로 나타났지만 파인 오일과 수산화동을 4:1로 혼용 처리하였을 때 발병률 49.9%와 방제 효과 41.7%로 가장 효과적이었다. 이상의 결과는 고추의 세균성 점무늬병과 탄저병의 발병을 파인 오일과 수산화동을 4:1로 혼용 처리함으로서 친환경적으로 방제할 수 있음을 나타낸다.

• Mycobiology
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• 제30권1호
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• pp.41-46
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• 2002

Composite vegetable crops grown in greenhouses and open fields in Korea were surveyed from 1995 to 1999. Occurrence of Sclerotinia rot was observed in 123 of 277 lettuce fields, in 11 of 18 head lettuce fields, in 12 of 14 endive fields, and in 4 of 38 garland chrysanthemum fields surveyed during the growing seasons. The disease most severely occurred up to 80% on lettuce. Incidence of the disease was as high as 20% at its maximum on endive and garland chrysanthemum but relatively low on head lettuce. Symptoms of the disease developed on leaves of all the composites, crowns of lettuce and head lettuce, and stems of garland chrysanthemum. Out of 240 isolates of Sclerotinia species obtained from the diseased composites, 169 isolates were identified as Sclerotinia sclerotiorum, and the others as S. minor based on their morphological and cultural characteristics. S. sclerotiorum was isolated from all the composites, and S. minor only from lettuce and endive. Eight isolates of S. sclerotiorum and four isolates of S. minor were tested for their pathogenicity to the composites by artificial inoculation. All the isolates of the two Sclerotinia spp. induced rot symptoms on the plants of the composites by artificial inoculation, which were similar to those observed in the fields. The pathogenicity tests revealed that there is no significant difference in virulence of the isolates to the composites and in susceptibility of the composites to the isolates.