• The Plant Pathology Journal
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• 제16권6호
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• pp.325-327
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• 2000

A leaf spot of rye (Secale cereale L.) was observed during the summer 1999 in Korea. A fungus associated with the disease was identified as Bipolaris sorokiniana (Sacc.) Shoem., based on the morphological characteristics of conidia and conidiophores. Pathogenicity of the fungus was proven by artificial inoculation on rye plants. This is the first record of leaf spot on rye caused by B. sorokiniana in Korea.

• 식물병과 농업
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• 제1권2호
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• pp.26-28
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• 1995

Anthracnose of tea tree, Camellia sinensis, occurred severely at tea plantation of Boseung, Chonnam. Irregular, dark brown spots appeared on tips and margins of mature leaves in early stage. As the disease progresses, the lesions were covered with numerous, small, black, slightly raised pustules (acervuli). The causal fungus of anthracnose was identified as Colletotrichum theae-sinensis (Miyake) Yamamoto. Symptoms by C. theae-sinensis appeared around 20 days after artificial inoculation.

• 식물병연구
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• 제19권1호
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• pp.49-54
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• 2013

Sclerotinia white rot disease was observed on 5 and 6-year-old ginseng (Panax ginseng) roots in Hongchun, Cheorwon, and Yanggu, Gangwon Province, Korea from 2006 to 2010. Symptoms included a brownish watery soft rot of the roots, and black sclerotia were often found on the rotten roots. The causal agent of the disease was identified as Sclerotinia nivalis based on cultural characteristics and sequence analyses of the internal transcribed spacer region of rDNA and ${\beta}$-tubulin gene with 100% sequence similarity. Pathogenicity tests were performed on 2-year-old ginseng roots with mycelium plugs without wounds. A watery soft rot of the roots and black sclerotia were observed 10 days after inoculation. These symptoms were identical to those observed on naturally infected roots. The same fungus was re-isolated from the lesions induced by artificial inoculation. This is the first report of sclerotinia white rot caused by S. nivalis on P. ginseng in Korea.

• 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.

• Mycobiology
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• 제38권2호
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• pp.133-136
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• 2010

Stromatal fruiting bodies of Cordyceps cardinalis were successfully produced in cereals. Brown rice, German millet and standard millet produced the longest-length of stromata, followed by Chinese pearl barley, Indian millet, black rice and standard barley. Oatmeal produced the shortest-length of fruiting bodies. Supplementation of pupa and larva to the grains resulted in a slightly enhanced production of fruiting bodies; pupa showing better production than larva. 50~60 g of brown rice and 10~20 g of pupa mixed with 50~60 mL of water in 1,000 mL polypropylene (PP) bottle was found to be optimum for fruiting body production. Liquid inoculation of 15~20 mL per PP bottle produced best fruiting bodies. The optimal temperature for the formation of fruiting bodies was $25^{\circ}C$, under conditions of continuous light. Few fruiting bodies were produced under the condition of complete darkness, and the fresh weight was considerable low, compared to that of light condition.

• The Plant Pathology Journal
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• 제17권1호
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• pp.45-51
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• 2001

A root rot/vine decline disease occurred naturally on bottle gourd-stocked watermelon, melon, oriental melon and squash grown in greenhouses, but not on these plants grown in fields. Self-rooted watermelon, cucumber, pumpkin and luffa were also proven to be hosts of the pathogen by artificial inoculation in this experiment. The pathogen was identified as Monosporascus cannonballus by comparing microscopic characteristics of fungal structures with those of previously identified fungal strains. Our field investigations showed that the temperature and electric conductivity of soil in infected greenhouses were higher and the soil moisture content was lower than in noninfected greenhouses. To investigate soil-environmental factors affecting disease development, greenhouse trials and inoculation experiments were conducted. The host plants inoculated and grown under conditions of high soil temperature and electrical conductivity ($35\pm2^{\circ}$, 3.2-3.5 mS) and with low soil moisture content (pF 3.0-4.5) were most severely damaged by the fungal disease. Since plants growing in greenhouses ae usually exposed to such environmental conditions, this may be the reason why the monosporascus root rot/vine decline disease has occurred only on cucurbits cultivated in greenhouses but not in field conditions.

• 식물병연구
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• 제28권4호
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• pp.245-247
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• 2022

In August 2021, we surveyed diseases of wild vegetables grown in Taebaek, Gangwon Province, Korea. During the disease survey, we observed severe damping-off symptoms in young edible aster (Aster scaber) plants in a vinyl greenhouse investigated. The incidence of the disease in the plants ranged from 5% to 20%. Diseased plants of edible aster were collected from the vinyl greenhouse, and fungi were isolated from petiole lesions of the diseased plants. Rhizoctonia sp. was consistently isolated from the petiole lesions. We examined morphological characteristics and anastomosis groups of nine Rhizoctonia sp. isolates obtained from the petiole lesions. The examination results revealed that all the isolates corresponded to Rhizoctonia solani AG-4 based on the morphological characteristics and anastomosis test. Three isolates of R. solani AG-4 were tested for their pathogenicity on edible aster plants by artificial inoculation. Inoculation tests showed that the tested isolates caused damping-off symptoms on the inoculated plants. The induced symptoms were similar to those observed in the vinyl greenhouse investigated. Damping-off of edible aster caused by R. solani AG-4 is first reported in this study.

• 한국균학회지
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• 제36권2호
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• pp.144-147
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• 2008

차가버섯균을 접종한 자작나무를 조사한 결과, 6$\sim$13cm 직경의 나무들에서 균이 확인되었다. 또한 나무 직경과 차가버섯균의 활착 간에는 유의성이 없는 것으로 나타났으며 접종 위치에 따른 활착 차이도 거의 없었다. 차가버섯균이 활착된 나무의 절단면 관찰에서는 차가버섯균이 위아래 방향으로는 활발히 움직인 반면에 방사상으로는 그렇지 않음을 알 수 있었다. 그리고 나무에서 분리한 균과 보관균 간의 대치배양에서는 대치선이 형성되지 않았다. 차가버섯 접종목에서 8종(Trichoderma reesei, T. atroviride, Cryptococcus neoformans, Botrytis cinerea, Fusarium sp., 명확하게 되지 않는 균 3종)의 오염균이 분리되었다.

• 식물병연구
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• 제20권4호
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• pp.270-274
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• 2014

본 연구의 목적은 신갈나무에서 참나무시들음병 병원균인 Raffaelea quercus-mongolicae의 지역별 균주와 기타 Raffaelea 속 근연종의 병원성을 평가하는 것이다. 이 연구에서는 신갈나무에 다양한 균주를 접종한 후, 변재부 내 변색정도로 각 균주의 병원성을 판단하였다. 그 결과 변색부의 평균 측면 확산 정도는 국내에서 분리한 Raffaelea quercus-mongolicae 병원균(8.69 cm)이 일본 병원균(7.51 cm)이나 기타 Raffaelea 속 근연종(3.35 cm)의 평균보다 높았고, 국내 지역별 Raffaelea quercusmongolicae 균주간에는 변색부 측면 확산정도가 4.71-14.90 cm로 병원성의 차이를 보였다. 균주간의 변색부 면적 확산정도는 $1.57-8.42cm^2$로 서로 다른 병원성의 차이를 보였으며, 가장 높은 병원성은 강원도에서 분리한 YY와 전라북도에서 분리한 wj43에서 나타났다.

• The Plant Pathology Journal
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• 제37권4호
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• pp.347-355
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• 2021

Ripe rot caused by Botryosphaeria dothidea is one of the serious diseases of postharvest kiwifruit. In order to control ripe rot on Actinidia chinensis cultivar 'Zesy002', several commercial agrofungicides were selected by an antifungal test on an artificial medium. Furthermore, disease suppression by the selected fungicides was evaluated on the kiwifruit by inoculation with a conidial suspension of B. dothidea. On the artificial media containing boscalid + fludioxonil was shown to be the most effective antifungal activity. However, in the bio-test pyraclostrobin + boscalid and iminoctadinetris were the most effective agrochemicals on the fruit. On the other hand, the infection structures of B. dothidea on kiwifruit treated with pyraclostrobin + boscalid were observed with a fluorescent microscope. Most of the fungal conidia had not germinated on the kiwifruit treated with the agrochemicals whereas on the untreated fruit the fungal conidia had mostly germinated. Electron microscopy of the fine structures showed morphological changes to the conidia and branch of hyphae on the kiwifruit pre-treated with pyraclostrobin + boscalid, indicating its suppression effect on fungal growth. Based on this observation, it is suggested that ripe rot by B. dothidea may be suppressed through the inhibition of conidial germination on the kiwifruit treated with the agrochemicals.