• Mycobiology
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• 제28권1호
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• pp.54-56
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• 2000

A black scab disease occurred on sword bean (Canavalia gladiata) in plastic film houses around Chinju area during the spring season of 1999. The disease started from flower bud, then moved to flower stalk, pod, petiole, cirrus, stem and leaves. The lesions started with small dark brown spots then were gradually expanded. Severely infected plants reached 37.4% of whole plant covered with scab. Numerous conidia were produced on the diseased flower disk, pod, floral axis, stem and leaves. Most of the conidia were appeared to be readily dispersed in the air, but the mycelia were not suggested causing of sooty mold by ectoparasitism. A fungus was isolated from the diseased stem, and inoculated to healthy plants to satisfy the Koch's postulates and proved the fungus was the causal agent of the disease. The isolated fungus grew on potato dextrose agar, forming greenish black to pale brown colonies. Conidia were ellipsoidal, fusiform or subspherical, mostly one-celled but occasionally septated. The conidia were $3.9{\sim}34.1{\times}2.7{\sim}5.1\;{\mu}m$ in size and formed in long branched chains on the erected conidiophores which were pale olivaceous brown and variable in length between $7.2{\sim}210.7\;{\mu}m$ in size. Ramoconidia were $7.6{\sim}29.2{\times}3.2{\sim}14.4\;{\mu}m$ in size. The fungus was identified as Cladosporium cucumerinum based on the above morphological characteristics. The optimum temperature for mycelial growth and conidial formation was about 15 to $25^{\circ}C$. Cladosporium scab of sword bean caused by the fungi has not been reported in Korea previously.

• 식물병연구
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• 제10권2호
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• pp.135-137
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• 2004

제주지역 감자재배포장에서 문제가 되고 있는 더뎅이병의 방제대책 마련의 일환으로 1997년과 2001년에 감자 더뎅이병 저항성인 품종을 선발하기 위한 시험을 실시한 결과 외국에서 도입하여 재배 가능성을 검토 중이거나 국내에서 재배중인 감자품종 중 더뎅이병 발생이 적은 포장에서는 알파, 젬칩, 대서, 조풍, 유곤골드 품종이 더뎅이병에 매우 강한 편이었으며, 더뎅이병 발생이 심한 포장에서는 젬칩, 대서, 조풍이 더뎅이병에 비교적 낮은 이병율을 보였다. 우리나라에서 재배되고 있는 주요 장려품종 중에는 수미, 추백, 조풍 품종이 더뎅이병에 저항성이었다.

• The Plant Pathology Journal
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• 제39권2호
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• pp.228-233
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• 2023

Two pear cultivars with different degrees of resistance to Venturia nashicola were evaluated on the basis of a disease severity rating for pear scab resistance under controlled environmental condition. Two inoculation techniques were tested: the procedure for inoculation by dropping conidia suspension of V. nashicola; the procedure by deposition of agar plug on the abaxial surface of pear leaves. All tested cultivars resulted in blight symptoms on the inoculated leaves and became spread to uninoculated region or other leaves. Although both methods provide satisfactory infection of V. nashicola on pear leaves, the mycelial plug method of inoculation was more reliable than the spray inoculation method for the evaluation of pear scab disease resistance. The incubation period of V. nashicola in the resistant pear cultivar, Greensis was longer than that in the susceptible cultivar, Hwasan.

• 한국균학회지
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• 제13권4호
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• pp.263-265
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• 1985

한국에 발생하는 배나무 검은별 무늬병 병원균의 특성과 병원성을 조사한 결과 한국에서 분리된 검은별 무늬병균의 분생자의 길이와 폭은 평균 $14.6-6.4\;{\mu}m$이었으며 분생자경의 길이와 폭은 평균 $13.5-4.6\;{\mu}m$이었다. 병원성 경정은 Flemish Beauty, Beurre Delicious, Winter Nelis (서양배), 신고(일본배)에 인공상처 접종한 결과 신고의 잎에서만 전형적인 검은별 무늬병의 병징이 재현 되었다. 이상의 결과로 보아 한국에서 발생하고 있는 배 검은별 무늬병균은 V. nashicola에 가까운 것으로 판정 되었다.

• 농약과학회지
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• 제18권4호
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• pp.434-438
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• 2014

Fluxapyroxad/pyraclostrobin 합제와 살균제를 9회 처리하는 처리체계의 검은별무늬병 방제효과를 조사하였다. 살균제가 처리되지 않은 무처리구의 이병엽률은 58.4%, 그리고 이병과율은 100%로 살균제 효과를 평가하기에 충분하였다. Fluxapyroxad/pyraclostrobin 합제만을 7회 처리한 처리구의 이병엽률은 평균 6.3%로 나타났고 방제가는 89.2%로 조사되었으며, 이병과율은 평균 16.7%, 방제가는 83.3%로 조사되었다. 서로 다른 계통의 살균제를 9회 처리한 검은별무늬병 처리체계의 효과를 조사한 결과, 이병엽률은 5.0%, 이병과율은 13.3%로, 각각의 방제가가 91.4%와 86.7%로 조사되었다. Fluxapyroxad/pyraclostrobin 합제 처리구와 비교해 보았을 때, 살균제를 9회 처리하는 처리체계에서 잎과 과실 모두에서 검은별무늬병의 발병률이 다소 낮게 나타났으나, 통계적인 유의성은 보이지 않았다. 이러한 결과는 수출전업농가에서 사용 가능한 새로운 살균제의 선발을 통한 효율적인 방제가 이루어 진다면 검은별무늬병 방제체계를 확립하는데 도움을 줄 수 있을 것으로 생각한다.

• 한국환경과학회지
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• 제32권11호
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• pp.777-788
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• 2023

Potato common scab disease is caused by pathogens belonging to Streptomyces spp. and results in a serious yield loss worldwide. Despite decades of research aimed at disease management, a definitive control method remains undiscovered. This study aims to explore the correlation between the C/N ratio and urea application with potato common scab pathogen dynamics and disease severity. We applied sawdust with a high C/N ratio and urea into the soil prior to potato cropping, both in pot and field experiments. Disease severity assessments and quantification of the TxtB gene were conducted at the harvest stage. Furthermore, culture experiments were performed to assess the direct impact of urea on the pathogen. Our findings revealed that higher disease severity was correlated with a high C/N ratio application and pathogenic gene quantity. Urea exhibited a direct influence on S. scabiei activity, reducing the disease severity in pot experiments. However, the effects of urea application on disease suppression in the conductive field were inconclusive. Although the results of urea application experiments displayed inconsistencies between pot and field trials, urea worked as the control to suppress S. scabiei activity. Further investigations are needed under various field conditions to confirm these findings.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2005년도 International Meeting of the Microbiological Society of Korea
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• pp.162-165
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• 2005

Potato scab, an important disease that affects developing tubers, causes a major problem in potato cultivation. The major potato cultivation areas in Korea are located in two Northern provinces, Gangwon and Gyeonggi, and two Southern provinces, Jeju island, and South Jeolla. In these areas, potato scab is widely distributed and has caused severe problem in potato cultivation. Therefore, potato-growing areas were surveyed for identification and distribution of potato scab pathogens from 1996 to 1999. Pathogenic Streptomyces strains were isolated from potato scab lesions and six representative Streptomyces species were characterized based on their phenotypic and molecular characteristics including, pathogenicity, physiological and morphological properties, analyses of 16SrRNA genes and 16S-23S ITS region, DNA relatedness, production of thaxtomin A, and the presence of nec1 and ORFtnp gene homologs. Three species were identified as previously described Streptomyces scabies, S. turgidiscabies, and S. acidiscabies, while other three species having distinct phenotypics properties were identified as novel S. luridiscabiei, S. puniciscabiei, and S. niveiscabiei.

• The Plant Pathology Journal
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• 제33권5호
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• pp.450-457
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• 2017

Scabs caused by Venturia carpophila greatly reduce the quality of the fruits of the Japanese apricot (Prunus mume) when the disease is not properly managed. The disease produces a superficial blemish that is unlikely to affect the overall yield of processed fruit, but reduce the value of fruit intended for the fresh market. Incidence rates of scab at sprayed and unsprayed orchards range from 0% to 21.5% and from 30.2% to 100%, respectively, in the major cultivation regions of Jeonnam Province during the growing season of 2009. The trends in disease progress were quite similar, regardless of regions, and cultivar Namgo was relatively less damaged by scab compared to cultivar Cheonmae among the tested Japanese apricot cultivars. The fruits on branches 1.5 m above the infected Japanese apricot trees and the stem-end parts of the infected fruits were more severely damaged by scabs, possibly because of rain and run-off facilitate dissemination of conidia of V. carpophila and subsequent infection of the fruits or branches. The conidia of V. carpophila were dispersed from March 24 to April 26 in 2010, and more conidia were dispersed from 2-year-old branches than 1-year-old branches. Since the control efficacies were higher than 90% after more than two applications of Trifloxystrobin WG at 10-day-intervals from mid April, it is that effective fungicides be applied at least two times at 10-day-intervals from the middle of April to manage scabs of Japanese apricot in orchards.

• 식물병연구
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• 제29권2호
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• pp.101-107
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• 2023

배 검은별무늬병을 일으키는 원인 병원균은 Venturia nashicola는 국내를 포함한 일본, 중국, 대만에서 가장 문제가 되는 대표적인 병이다. 이 병을 관리하기 위해서는 주로 화학적 방제에 의존하는 방식으로 관리가 되고 있었다. 하지만 지속인 화학적방제는 환경오염뿐만 아니라 병원균의 저항성 출현을 야기하여 보다 지속 가능한 관리방안이 필요한 시점이다. 이에 V. nashicola의 생환 및 감염 특성을 이해하고 과거부터 이어져온 달력형 방제나 특정 계통의 살균제 연용에서보다 기상환경조건에 따라 능동적인 방제시기 설정이 필요한 상황이다. 이 논문에서는 배 검은별무늬병인 V. nashicola의 병환, 감염특성 그리고 방제체계에 대한 내용을 정리하고 보다 효과적인 방제관리체계에 대한 방안을 논의하고자 다양한 연구결과들을 리뷰하였다.

• 한국자원식물학회지
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• 제32권4호
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• pp.296-302
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• 2019

본 연구는 주요 배유전자원 43 accession을 대상으로 육종소재로 활용할 수 있는 배 유전자원 선발과 종내 또는 종간 5개 교배집단 609 seedling에서 배 검은별무늬병 저항성 발현을 확인하고자 수행하였다. P. pyrifolia, P. bretschneideri, P. ussuriensis는 검은별무늬병 병든 과실률이 각각 59.5, 73.4, 63.0%, P. pyrifolia와 P. bretschneideri 종간 교잡으로 얻어진 품종은 77.7%로 병든 과실률이 비교적 높았으나 P. communis, P. pyrifolia ${\times}$ P. communis종간교잡에 속하는 품종들은 15% 미만의 병든 과실률을 보였다. 검은별무늬병에 대한 저항성을 종별로 구분하여 Duncan 검정한 결과, P. bretschneideri, P. pyrifolia, P. ussuriensis, pyrifolia ${\times}$ P. bretschneideri 종이 P. communis, P. pyrifolia ${\times}$ P. communis두 개 종 그룹보다 검은별무늬병 병든 과실률이 유의하게 높았고 이러한 경향은 교배집단에서도 동일하였다. P. pyrifolia 종내 교배집단은 80% 이상의 검은별무늬병 감염률을 보인 반면, P. pyrifolia ${\times}$ P. communis의종간교배 집단은 2% 수준의 낮은 배 검은별무늬병 감염률을 보였다. P. pyrifolia 와 P. communis를 종간교배 하면 서양배의 저항성 인자가 우성으로 작용하여 그 후대에서 배 검은별무늬병에 강한 개체들이 대부분 얻어지기 때문에 P. communis는 배 검은별무늬병저항성 품종 육종소재로 적합하다.