• 식물병연구
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• 제11권1호
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• pp.85-87
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• 2005

2003년 6월에 경상남도 농업기술원 함양 약초시험포장에 재배중임 섬쑥부쟁이에서 Sclerotium rolfsii에 의한 흰비단병이 발생되였다. 병징은 줄기와 지제부위가 수침상으로 물러지고 부패하면서 암갈색으로 변하고 그 위에 흰색의 곰팡이가 솜털처럼 생기고, 병반부와 지제부위의 토양 표면에 갈색의 둥근 균핵을 많이 형성되었다. 병원균은 감자한천 배지상에서 왕성하게 생장하였으며 균사생장 중에 특유의 clamp connection이 관찰되었다. 균사의 크기는 3~$8\mu\textrm{m}$이었다. 감자한천 배지에서 갈색을 띤 구형 또는 부정형의 많은 균핵을 형성하였는데 균핵의 크기는 1~3mm였다. 균사생육 적온은 $30^{\circ}C$였다. 이상과 같이 병징과 균학적 특징 및 병원성을 검정한 결과, 이 병을 Sclerotium rolfsii에 의한 섬쑥부쟁이 흰비단병으로 명명하고자 한다.

• The Plant Pathology Journal
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• 제16권4호
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• pp.242-245
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• 2000

In 1999 and 2000, a rot of graft-cacti including Hylocereus trigonus (three-angled cactus), Gymnocalycium mihanovichii, and Chamaecereus silvestrii occurred in several greenhouses in major cactus-growing areas of Korea. Typical symptoms included a moist, light brown rot or a watery rot of the stems. A Colletotrichum sp. was isolated from the lesions. The fungus formed dark gray, dense or floccose colonies on potato dextrose agar, frequently forming many light pink acervuli often surrounded with setae. The hyaline, cylindrical conidia were one-celled with round ends. Appressoria were mostly semicircular or clavate. Thin-walled asci contained eight, one-celled, hyaline ascospores (biseriate in ascus). Ascopspores were strainht or curved, ellipsoidal or subcylindrical. Based on these characteristics, the fungus was identified as Glomerlla cingulata (anamorph : C. gloeosporioides). Wound inoculation of basal stems of the cactus by the mycelial plugs or conidia produced symptoms identical to those described above. Various cactus species were compared in susceptibility using stem disc inoculation. Cereus tetragonus, Eriocereus jusbertii, Myrtillocactus geomentrizans, and three-angled cacti from Mexico and Taiwan were susceptible, but C. peruvianus (Peruvian apple cactus) and Harrisia tortuosa not. This is the first report of G. cingulata causing stem rot of graft-cactus in Korea.

• The Plant Pathology Journal
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• 제35권3호
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• pp.189-199
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• 2019

In this research, the relationships among the 31 microsatellite markers with charcoal rot disease resistance related indices in 130 different soybean cultivars and lines were evaluated using association analysis based on the general linear model (GLM) and the mixed linear model (MLM) by the Structure and Tassel software. The results of microsatellite markers showed that the genetic structure of the studied population has three subpopulations (K=3) which the results of bar plat also confirmed it. In association analysis based on GLM and MLM models, 31 and 35 loci showed significant relationships with the evaluated traits, respectively, and confirmed considerable variation of the studied traits. The identified markers related to some of the studied traits were the same which can probably be due to pleiotropic effects or tight linkage among the genomic regions controlling these traits. Some of these relationships were including, the relationship between Sat_252 marker with amount of charcoal rot disease, Satt359, Satt190 and Sat_169 markers with number of microsclerota in stem, amount of charcoal rot disease and severity of charcoal rot disease, Sat_416 marker with number of microsclerota in stem and amount of charcoal rot disease and the Satt460 marker with number of microsclerota in stem and severity of charcoal rot disease. The results of this research and the linked microsatellite markers with the charcoal rot disease-related characteristics can be used to identify the suitable parents and to improve the soybean population in future breeding programs.

• 한국식물병리학회지
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• 제14권5호
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• pp.458-462
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• 1998

Stem rot symptomof lily caused by Phytophthora was observed in Chilkok, Korea in 1997. Oogonia of Phytophthora were abundantly developed on epidermal tissues of stem and leaves of the diseased plants. The casual fungus was identified as Phytophthora cactorum based on their cultural and morphological characteristics. Sporangia were markedly papillate and the shape was broadly spherical to ovoid both on agar and in water. The size was 28~44$\times$20~28 ${\mu}{\textrm}{m}$ (av. 36~24) and a short pedicel was attached to each sporangium. The fungus was homothallic and oogonia were 28~32 ${\mu}{\textrm}{m}$ (av. 30) in size and slightly yellow. Antheridia were paragynous and spherical or irregularly club shaped. Optimal temperature for mycelial growth was 25~27$^{\circ}C$. The fungus did not grow under 6$^{\circ}C$ and over 34$^{\circ}C$. The fungus was highly pathogenic to three cultivars of lily. Symptom was developed at 4-day after artificial inoculation with zoospores (103 cell/ml) on the stem of lily. The symptom was identical to those produced by natural infection in the field and the plant was blighted within 14 days after inoculation.

• 한국균학회지
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• 제47권4호
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• pp.443-446
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• 2019

In 2017, wilting symptom was observed on seedlings of Anthurium andraeranum in Youngin, Korea. Brownish lesions with water soaking were developed on the stems and roots of the infected plants. The stems and leaves wilted and finally died. One fungal isolate was obtained in pure culture. Morphological features and nucleotide sequences of internal transcribed spacer rDNA and cytochrome oxidase subunit II mt DNA were analyzed. The results of this study indicated that the fungus is identified as Phytopythium vexans. Pathogenicity tests showed the isolate was pathogenic to the seedlings of A. andraeanum. To our knowledge, this is the first report of P. vexans causing stem rot on A. andraeanum in Korea.

• Mycobiology
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• 제38권4호
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• pp.339-342
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• 2010

Basal stem rot symptoms were found on blueberry seedlings imported from the United States of America in 2008. The fungus obtained from the diseased seedlings was identified as Calonectria colhounii based on morphological and molecular characteristics. The consignments of the blueberry seedlings infected with C. colhounii were destroyed to prevent introduction of the fungus to Korea.

• 한국식물병리학회지
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• 제10권4호
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• pp.314-318
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• 1994

Incidence of stem rot on carnation (Dianthus caryophyllus L.) ranged 11 to 29% in Namwon and Chongup area during the growing seasons from 1993 to 1994. Among 129 isolates from carnations in Namwon, 77 isolates were identified as Rhizoctonia solani, 38 isolates were Fusarium oxysporum and 14 isolates were not identified. Among 169 isolates in Chongup, 19 isolates were identified as R. solani, 106 isolates as F. oxysporum and 44 isolates were not identified. Among 77 isolates of R. solani isolated from the specimens of Namwon, 52 isolates were classified as anastomosis group AG 2-2 by anastomosis test, 14 isolates as AG 2-1 and 11 isolates as AG 4. Among 19 isolates from specimens of Chongup, 14 isolates were classified as anastomosis group AG 2-2 and 5 isolates as AG 4. Pathogenicity tests revealed that isolates of F. oxysporum and R.solani AG 2-2 were highly virulent and isolates of R.solani AG 2-1 and AG 4 were mildly virulent.

• 한국식물병리학회지
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• 제10권1호
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• pp.64-67
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• 1994

Crown rot was found find tomatoes growing on a rockwool culture system in a glasshouse at Dongkwangyang in 1992. The disease occurred on the stem of 'Trust' tomato plants with 3~4 cluster of flowers. Infected plants showed stem girdling and necrosis at or slightly above the rockwool line. Internal tissues of crown and stem including cortex, vascular bundle, and pith became decayed resulting in a chocolate-brown discoloration extending no more than 10~15 cm above the crown. Diseased tomato plants with the similar symptoms were found at Ansung and Taejon where tomatoes were grown on either rockwool or soil in plastic greenhouses. The size of macroconidia of Fusarium isolated from a diseased plant was 26.0~41.6$\times$2.9~4.7${\mu}{\textrm}{m}$, and microconidia were formed on short monophialide and the size was 3.6~12.5$\times$2.9~3.6 ${\mu}{\textrm}{m}$. Morphological characteristics and inoculation tests indicated that the causal organism of the disease was Fusarium oxysporum.

• 식물병연구
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• 제10권1호
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• pp.21-24
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• 2004

2002년 경남 하동군 진교면 노지재배 포장과 2003년 진주시 문산읍 촉성재배 비닐하우스 고추에서 이상증상이 발생하였다 병징은 지제부의 줄기가 수침상으로 물러지고 부패하면서 암갈색으로 변하고 시들면서 말라 죽는다. 병반부에 흰색의 곰팡이가 솜털처럼 생기고, 병반 부위와 토양 표면에 갈색의 둥근 균핵이 많이 형성된다 병원균의 균사생장 및 균핵형성은 감자한천배지에 배양시 3$0^{\circ}C$에서 가장 양호하였다. 균핵은 갈색 또는 암갈색으로 크기는 1.0∼2.7 mm이었다. 균사 특유의 clamp connection이 관찰되었고 균사 폭은 3.6∼10.2 $\mu\textrm{m}$이었다. 본 병원균을 Sclerotium rolfsii로 동정하였으며 고추 흰비단병으로 명명할 것을 제안한다.

• The Plant Pathology Journal
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• 제31권1호
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• pp.67-71
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• 2015

During late August and early September 2011, stem rot symptoms were observed on adzuki bean plants (Vigna angularis) growing in fields located in Beijing and Hebei Province, China, respectively. In this study, four isolates were obtained from infected stems of adzuki bean plants. Based on their morphology, and sequence and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analyses of the ribosomal DNA internal transcribed spacers (rDNA-ITS) region, the four isolates were identified as Rhizoctonia solani in anastomosis group (AG) 4 HGI. Pathogenicity tests showed that all isolates were strongly pathogenic to adzuki bean and resulted in serious wilt symptoms which was similar to observations in the fields. Additionally, the isolates infected several other crops and induced related rot on the roots and basal stems. To our knowledge, this is the first report of Rhizoctonia solani AG 4 HGI causing stem rot on adzuki bean.