• 한국어병학회지
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• 제32권2호
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• pp.123-127
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• 2019

In this study, white spots appearing in carapace of imported white leg shrimp Litopenaeus vannamei were observed by macroscopic and microscopic examination. White spots due to white spot disease showed two types, white spots with a regular circular shape ranging from 0.4 mm to 1.7 mm and white spots with an irregular shape ranging from 0.05 mm to 2 mm. White spots due to other causes showed four types that appeared as crystalized materials in range of 100 ㎛ around the tegumental gland, as polygonal inorganic deposits ranging from 58 ㎛ to 188 ㎛, as Linear inorganic deposits ranging from 0.8 mm to 9 mm, as brownish spots ranging from 0.1 mm to 0.4 mm, and brownish spots containing melanin ranging from 0.1 mm to 2 mm. As a result, white spots occurred in imported white leg shrimp Litopenaeus vannamei were divide two type, due to white spot disease or other causes, for quarantine works.

• 한국식물병리학회지
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• 제14권6호
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• pp.676-681
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• 1998

Disease incidence of Codonopsis lanceolata was surveyed at the major cultivating fields in Chonbuk province in 1996 to 1997. The main diseases of Codonopsis lanceolata were ovserved as leaf spot caused by Septoria codonopsis, anthracnose by Glomerella cingulata, brown leaf spot by Cercospora sp., rust by Coleosporium koreanum, powdery mildew by Erysiphe sp., Fusarium wilt caused by Fusarium oxyporum, and white root rot by Sclerotium rolfsii. Anthracnose, leaf spot and brown leaf spot occurred severely on leaves from early July to late August. They were caused early fallen leaves. Fusarium wilt and white root rot occurred severely on stem and below the soil line in late August. They resulted in withering to death or chlorosis and fallen of leaves. Disease incidence of Codonopsis lanceolata was also substantially different in occurrence with a method of cultivation in late growth stage. Fusarium wilt and white root rot were more severe with a method of no support cultivation than those with a method of support cultivation with a stick. Fusarium wilt occurred 48.8% in a method of no support cultivation but 3.1% in a method of support cultivation with a stick. And white root rot occurred 18.9% in a method of no support cultivation but 0.3% in a method of no support cultivation with a stick. Thus, it proved that soil-borne diseases could be controlled support cultivation with a stick.

• Journal of Microbiology and Biotechnology
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• 제17권3호
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• pp.511-515
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• 2007

White-spot syndrome virus (WSSV) is a devastating, infectious virus affecting shrimp. Although sensitive techniques involving PCR have been developed to assist farmers in screening shrimp (brood stock) for WSSV prior to stocking ponds, such practices have not yet been applied in Korea. Despite the rationality of implementing screening, there has been some doubt as to whether the stocking of WSSV-PCR-negative fly epidemiologically decreases white-spot disease outbreaks. Here, we report a retrospective analysis of data from shrimp farms in the western coast of Korea where WSSV-PCR-negative brood stocks were used to stock rearing ponds. A total of 366 shrimp from Heuksan Island were sampled for WSSV with PCR. Of the tested shrimp, 7.2% (28 brood stocks) were identified as WSSV positive; only WSSV-PCR-negative shrimp were used for brood stocks. Total unit production (final shrimp production/ the area of the ponds) was higher, at 1.96, in ponds where WSSV-PCR-negative shrimp were used, as compared with 1.02 in other ponds in Korea in 2004. This retrospective analysis of WSSV in Korea may be useful to the shrimp aquaculture industry, suggesting a testable hypothesis that may contribute to the eventual control of WSSV outbreaks.

• 아시안잔디학회지
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• 제14권1호
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• pp.241-250
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• 2000

In 1997, a new disease on creeping bentgrass and Kentucky bluegrass occurred in the green and fairway of a few golf courses in Korea. The disease spread gradually throughout the country and became a threat to turfgrass management. Symptoms of the disease consisted of small, circular, and sunken patches sized 3~5cm in diameter. The disease named as a dollar spot following its characteristic symptoms of circular blight and bleach on the green. The disease peaked two times in a year from April to June and from late August to October and white cottony mycelia of the causal fungus developed on diseased turfs in the early morning when the conditions were favored. A causal fungus was consistently isolated from the infected tufgrass and seven isolates originated from seven golf courses located in six provinces were selected for further study. The fungus produced abundant white aerial mycelia on PDA and turned to dark gray or light brown as it aged. Width of the mycelium was ca. $5~8\mu\textrm{m}$. While sclerotia were not readily formed on the medium, scattered small and dark colored stromata were developed on the surface. The fungus grew well on PDA between 5 to $30^{\circ}C$ and maximally around $25^{\circ}C$. Based on investigated mycological and cultural characteristics, the causal agent of dollar spot was identified as Sclerotinia homoeocarpa. The fungus showed strong pathogenicity to several turfs as creeping bentgrass, Kentucky bluegrass, perennial ryegrass, tall fescues, and zoysiagrass.

• The Plant Pathology Journal
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• 제16권6호
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• pp.328-330
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• 2000

A terget leaf spot of red and white clovers was observed during 1998-2000 growing seasons in several fields of Chungnam and Chungbuk provinces in Korea. Lesions were circular to oval in outline, brown to dark brown, ranging from a pinpoint to 3-4 mm in diameter, often concentrically zonate and presenting a target effect. A fungus associated with the disease was identified as Stemphylium sarciniforme based on the morphological characteristics of the conidiophores and conidia. The fungus was pathogenic on red and white clovers in the inoculation test. This is the first record of a terget leaf spot of red and white clovers in Korea.

• 한국어병학회지
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• 제25권3호
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• pp.271-277
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• 2012

2012년 5월에서 11월 사이에 우리나라 넙치, 조피볼락, 무지개송어, 뱀장어, 흰다리새우, 전복 양식장에서 발생하는 폐사피해를 표본조사를 통해 모니터링하였다. 조사의 방식은 해당 양식장과 거래하고 있거나 관계를 맺고 있는 전국의 수산질병관리사 조사요원의 직접 현장 방문을 통한 면접과 표준 매뉴얼을 통한 진단을 통하여 실시하였다. 조사기간 중 넙치 양식장에서는 총 27.9%의 누적 피해율을 보여주었고, 이중 스쿠티카병, 연쇄구균병, VHS, 비감염성 원인에 의한 폐사, 비브리오병, 활주세균병의 순으로 폐사피해가 높은 것으로 나타났다. 조피볼락 양식장에서는 13.6%의 누적 피해율을 보여주었고, 아가미 흡충병, 연쇄구균병, 비브리오병, 활주세균병, 비감염성 원인에 의한 폐사 순의 폐사피해가 나타났다. 무지개송어의 경우 총 17.1%의 피해율을 기록하였고, 비감염성 원인에 의한 폐사와 백점병이 주된 폐사 원인으로 집계되었다. 뱀장어의 경우 비교적 낮은 0.6%의 피해율을 기록하였으며, 에드워드병, 백점병, 아가미흡충병이 주된 피해요인이었다. 흰다리새우는 71.2%의 피해율을 보였으며, 대부분 비감염성 원인에 의한 폐사으로 집계되었고, 바이러스성 흰반점병도 12.5%의 피해를 준 것으로 나타났다. 전복의 경우 10.7%의 피해율 모두가 비감염성 원인에 의한 폐사 피해인 것으로 조사되었다.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2001년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.519-520
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• 2001

1993년 초여름부터 발생한 양식대하의 WSBV에 의한 대량 폐사가 1996년에는 폐사율이 거의 75％에 이를 정도로 피해가 많이 발생하였다(허 등, 1998). WSBV에 감염된 새우는 두흉갑과 체표에 흰반점 증상이 나타나므로 병명을 일반적으로 White spot syndrome disease(WSSD)라고 하고 원인 바이러스를 WSBV라 일반적으로 명명하고 있고 이와 같은 증상으로 인한 새우의 대량 폐사는 아시아 전역에서 일어나고 있다(Chou 등, 1995; Inouye 등, 1996). (중략)

• 한국양식학회:학술대회논문집
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• 한국양식학회 2001년도 추계 한국양식학회 학술대회
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• pp.227.2-228
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• 2001

• Journal of Microbiology and Biotechnology
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• 제11권3호
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• pp.394-398
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• 2001

Because of the great concern over the possibility of contamination from the rod-shaped nuclear virus (PRDV) from Japan and white spot virus (WSSV) from Taiwan, most eggs used in Korean shrimp farms are currently obtained from local broodstock. In addition, the screening of imported broodstock for any viral presence at the National Fisheries Research and Development Institute is also mandatory. Nonetheless, massive mortality from white spot syndrome continues in Korea. In the present study, we present an improved PCR method to use tissue-extracted DNA instead of viral DNA extracted from a purified virus based on a sucrose density gradient, and produced results within 8 h. In 1998, this modified PCR method was able to detect that diseased Penaeus japonicus were infected within 8 h. In 1998, this modified PCR method was able to detect that diseased Penaeus japonicus were infected only with PRDV, while Fenneropenaeus chinensis were infected with both PRDV and WSSV. In 1999, PRDV and WSSV were detected in F. chinensis with signs of infection, but not with WSSV alone.

• BMB Reports
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• 제37권6호
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• pp.726-734
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• 2004

White spot disease (WSD) is caused by the white spot syndrome virus (WSSV), which results in devastating losses to the shrimp farming industry around the world. However, the mechanism of virus entry and spread into the shrimp cells is unknown. A binding assay in vitro demonstrated VP28-EGFP (envelope protein VP28 fused with enhanced green fluorescence protein) binding to shrimp cells. This provides direct evidence that VP28-EGFP can bind to shrimp cells at pH 6.0 within 0.5 h. However, the protein was observed to enter the cytoplasm 3 h post-adsorption. Meanwhile, the plaque inhibition test showed that the polyclonal antibody against VP28 (a major envelope protein of WSSV) could neutralize the WSSV and block an infection with the virus. The result of competition ELISA further confirmed that the envelope protein VP28 could compete with WSSV to bind to shrimp cells. Overall, VP28 of the WSSV can bind to shrimp cells as an attachment protein, and can help the virus enter the cytoplasm.