• The Plant Pathology Journal
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• 제21권1호
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• pp.27-32
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• 2005

Leaf anthracnose was observed on leaves of Japanese spindle tree in Seoul, Korea from autumn 2003 to spring 2004. The causal fungus was purely isolated from he leaf spot lesions and cultured on PDA. The colony on PDA was cream to orange but blackish in the center n old cultures. Conidia were formed in blackish orange asses and were cylindrical in shape, measured 13-17${\times}$5-7 ${\mu}$m in size. Blackish brown setae were often observed on PDA and ranged up to 100 ${\mu}$m in length. Based on morphological and ITS region sequence analyses, the fungal strain was identified as Colletotrichum boninense. Koch’s postulates were fulfilled by inoculating tree leaves with 1 ${\times}$ $106^6$ conidia per ml in a moist chamber. This is the first study on the pathogenicity, growth and phylogenetic characteristics of C. boninense causing leaf anthracnose on Japanese spindle tree in Korea.

• Mycobiology
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• 제36권4호
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• pp.274-276
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• 2008

Anthracnose occurred frequently on leaf sheaths of Welsh onions grown in Gangwha island, Korea in November, 2007. The disease incidence was as high as 30% in five fields investigated. A total of 20 single spore isolates of Colletotrichum species were obtained from the affected plants, and all the isolates were identified as Colletotrichum circinans based on their morphological and cultural characteristics. Three isolates of the fungus caused anthracnose symptoms on the leaf sheaths of Welsh onions by artificial inoculation, which were similar to those observed during the field survey. In this study, the mycological and pathological characteristics of C. circinans identified as causing anthracnose of Welsh onions are clarified.

• 한국유기농업학회지
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• 제22권4호
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• pp.705-718
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• 2014

본 연구는 인삼점무늬병과 탄저병에 대한 친환경자재로 만들어진 친환경 살균제의 억제효과를 알아보기 위해서 수행을 했다. 인삼 점무늬병과 인삼 탄저병들은 인삼뿌리가 비대하기 시작하기 전에 낙엽을 시켜서 수확량을 크게 감소하는 주요한 병들이다. 천연칼슘, 녹차추출물, 홍삼박 술등은 A. panax에 의해서 유발된 인삼 점무늬병에 대해서 상당한 억제효과를 보였고 게 껍질 발효액과 익모초자연즙액은 C. gloeosporioides에 의해서 유발된 인삼탄저병에 대해서 큰 억제효과를 나타내었다. 이들 친환경 살균제는 치료효능보다 대체적으로 예방효능이 더 우수 하였다. 그러므로 이들 친환경 자재들은 인삼 유기재배포장에서 사용할 수 없는 화학농약을 대체하는 살균제로써 이용할 수 있고 그들의 억제효과를 극대화하기 위해 발병 전에 처리를 해야 한다.

• The Plant Pathology Journal
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• 제24권1호
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• pp.46-51
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• 2008

With the goal of achieving better integrated pest management for hot pepper, a disease-forecasting system was compared to a conventional disease-control method. Experimental field plots were established at Asan, Chungnam, in 2005 to 2006, and hourly temperature and leaf wetness were measured and used as model inputs. One treatment group received applications of a protective fungicide, dithianon, every 7 days, whereas another received a curative fungicide, dimethomorph, when the model-determined infection risk (IR) exceeded a value of 3. In the unsprayed plot, fruits showed 18.9% (2005) and 14.0% (2006) anthracnose infection. Fruits sprayed with dithianon at 7-day intervals had 4.7% (2005) and 15.4% (2006) infection. The receiving model-advised sprays of dimethomorph had 9.4% (2005) and 10.9% (2006) anthracnose infection. Differences in the anthracnose levels between the conventional and model-advised treatments were not statistically significant. The efficacy of 10 (2005) and 8 (2006) applications of calendar-based sprays was same as that of three (2005 and 2006) sprays based on the disease-forecast system. In addition, we found much higher the IRs with the leaf wetness sensor from the field plots comparing without leaf wetness sensor from the weather station at Asan within 10km away. Since the wetness-periods were critical to forecast anthracnose in the model, the measurement of wetness-period in commercial fields must be refined to improve the anthracnose-forecast model.

• The Plant Pathology Journal
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• 제37권4호
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• pp.356-364
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• 2021

This study was to investigate defense mechanisms on cassava induced by salicylic acid formulation (SA) against anthracnose disease. Our results indicated that the SA could reduce anthracnose severity in cassava plants up to 33.3% under the greenhouse condition. The 𝛽-1,3-glucanase and chitinase enzyme activities were significantly increased at 24 hours after inoculation (HAI) and decrease at 48 HAI after Colletotrichum gloeosporioides challenge inoculation, respectively, for cassava treated with SA formulation. Synchrotron radiation-based Fourier-transform infrared microspectroscopy spectra revealed changes of the C=H stretching vibration (3,000-2,800 cm^-1), pectin (1,740-1,700 cm^-1), amide I protein (1,700-1,600 cm^-1), amide II protein (1,600-1,500 cm^-1), lignin (1,515 cm^-1) as well as mainly C-O-C of polysaccharides (1,300-1,100 cm^-1) in the leaf epidermal and mesophyll tissues treated with SA formulations, compared to those treated with fungicide carbendazim and distilled water after the challenged inoculation with C. gloeosporioides. The results indicate that biochemical changes in cassava leaf treated with SA played an important role in the enhancement of structural and chemical defense mechanisms leading to reduced anthracnose severity.

• 식물병연구
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• 제8권1호
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• pp.45-49
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• 2002

딸기탄저병의 발병특성은 정식 직후 격발하다가 시간이 지날수록 발병율이 감소하였으며, 11월 이후에는 발병이 감소하였다. 정식 직후에는 주로 런너로 침입하였으나 엽병 제거 후는 제거한 상처부위로 주로 침입을 하였다. 식물체의 부위별로는 런너에서 가장 강한 병원력을 보였으며 접종방법별로는 생장점 부위로 관주를 할 경우 가장 발병율이 높았다. 딸기탄저병에 의해 고사된 포기를 제거한 자리에 건전한 포기를 심었을 경우 옮겨 심은 포기에서는 발병이 되지 않았다.

• Mycobiology
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• 제29권2호
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• pp.107-109
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• 2001

Anthracnose symptoms severely occurred up to 50% on leaves of English ivy growing in greenhouses in Cheongwon area of Korea during disease survey in April, 2000. The symptoms developed as concentric spots with dot-like acervuli on leaves of the plant. A total of 24 isolates of Colletotrichum sp. were obtained from the spotted lesions and identified as Colletotrichum trichellum based on the morphological and cultural characteristics. Leaf spots similar to the original anthracnose symptoms were induced on the host leaves by artificial inoculation with the isolates of the fungus. This is the first record of C. trichellum causing anthracnose of English ivy in Korea.

• Mycobiology
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• 제30권1호
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• pp.57-59
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• 2002

Anthracnose symptoms severely occurred up to 100% on leaves of May lily grown in four locations in Korea during a disease survey in 2001. The symptoms appeared as circular to irregular spots with brown to dark brown discoloration on leaves of the plant, and severely infected leaves blighted. A total of 35 isolates of Colletotrichum sp. was obtained from the spotted lesions and identified as Colletotrichum liliacearum based on the morphological and cultural characteristics. Leaf spots similar to the original anthracnose symptoms were induced on the host leaves by artificial inoculation with the isolates of the fungus. This is the first report that C. liliacearum causes anthracnose of May lily.

• 한국식물병리학회지
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• 제11권3호
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• pp.224-229
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• 1995

Occurrence and incidences of major diseases of peach (Prunus persicae pv. vulgaris), leaf curl caused by Taphrina deformans, bacterial shot hole caused by Xanthomonas campestris pv. pruni, brown rot caused by Monilinia fructicola, and anthracnose caused by Glomerella cingulata in peach orchards in Cheongdo and Kyungsan areas of Gyeongbuk province, Korea, were investigated for four years from 1990 to 1993. In leaf curl and bacterial shot hole which mainly occurred on leaves, frist disease occurrences were dated from late April to early May. The maximum leaf curl incidence was dated in mid May, while dates of the maximum bacterial shot hole incidence varied from mid May to mid August depending on the years surveyed. In brown rot and anthracnose on fruit, the first disease occurrence dates ranged from early June to early August; however, the maximum disease incidences for both were invariably dated in late August. The disease incidences on the dates of the maximum incidences differed year by year, and the averages for the 4 years were 13.2%, 10.5%, 10.9% and 3.8% for leaf curl, bacterial shot hole, brown rot and anthracnose, respectively. Especially in the leaf curl disease, the first disease occurrence dates and the maximum disease incidences matched with the amounts of precipitation of rain up to April, suggesting that the disease occurrence may be related to the precipitation during the early season. The occurrence of leaf curl was somewhat higher in cultivar“Baekmi”than other cultivars. All of the major disease occurred more in hilly orchards than in plain ones.

• Mycobiology
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• 제30권1호
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• pp.31-36
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• 2002

Soil bacteria were screened for the ability to control cucumber anthracnose caused by Colletotrichum orbiculare through induced systemic resistance(ISR). Sixty-four bacterial strains having in vitro antifungal activity were used for selecting ISR-inducing strains in cucumber. Cucumber seeds(cv. Baeknokdadagi) were sown in potting mixtures incorporated with the soil bacteria, at a rate of ca. $10^8$ cells per gram of the mixture. Two week-old plants were then transplanted into the steam-sterilized soil. Three leaf-stage plants were inoculated with a conidial suspension($5{\times}10^5$ conidia/ml) of C. orbiculare. Diseased leaf area(%) and number of lesions per $cm^2$ leaf were evaluated on third leaves of the plants, $5{\sim}6$ days after inoculation. Among 64 strains tested, nine strains, GC-B19, GC-B35, GK-B18, MM-B22, PK-B14, RC-B41, RC-B64, RC-B65, and RC-B77 significantly(P=0.05) reduced anthracnose disease compared to the untreated control. In contrast, some bacterial strains promoted susceptibility of cucumber to the disease. From the repeated experiments using the nine bacterial strains, GC-B19, MM-B22, PK-B14, and RC-B65 significantly(P=0.05) reduced both diseased leaf area(%) and number of lesions per $cm^2$ leaf in at lease one experiment. These strains with control efficacy of $37{\sim}80%$ were determined to be effective ISR-inducing strains.