• The Plant Pathology Journal
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• 제32권2호
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• pp.157-161
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• 2016

Gamma irradiation was evaluated for its in vitro and in vivo antibacterial activity against a postharvest bacterial pathogen, Erwinia carotovora subsp. carotovora (Ecc). Gamma irradiation in a bacteria cell suspension resulted in a dramatic reduction of the viable counts as well as an increase in the amounts of DNA and protein released from the cells. Gamma irradiation showed complete inactivation of Ecc, especially at a dose of 0.6 kGy. In addition, scanning electron microscopy of irradiated cells revealed severe damage on the surface of most bacterial cells. Along with the morphological changes of cells by gamma irradiation, it also affected the membrane integrity in a dose-dependent manner. The mechanisms by which the gamma irradiation decreased the bacterial soft rot can be directly associated with the disruption of the cell membrane of the bacterial pathogen, along with DNA fragmentation, results in dose-dependent cell inactivation. These findings suggest that gamma irradiation has potential as an antibacterial approach to reduce the severity of the soft rot of paprika.

• 식물병연구
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• 제20권2호
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• pp.129-131
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• 2014

In February 2014, gray mold rotting symptoms were observed in carrots in cold storage at Gangneung, Gangwon province, Korea. The typical symptom of gray mold rot showed abundant blackish gray mycelia and conidia was observed on the infected root. The pathogen was isolated from infected root and cultured on PDA for further fungal morphological observation and confirming its pathogenicity according to Koch's postulates. Results of morphological data, pathogenicity test and rDNA internal transcribed spacer (ITS 1 and 4) sequence showed that the postharvest gray mold rot of carrot was caused by Botyrtis cinerea. This is the first report of postharvest gray mold rot on carrot in Korea.

• Mycobiology
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• 제42권4호
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• pp.409-411
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• 2014

In March 2014, a kohlrabi stem rot sample was collected from the cold storage room of Daegwallyong Horticultural Cooperative, Korea. White and fuzzy mycelial growth was observed on the stem, symptomatic of stem rot disease. The pathogen was isolated from the infected stem and cultured on potato dextrose agar for further fungal morphological observation and to confirm its pathogenicity, according to Koch's postulates. Morphological data, pathogenicity test results, and rDNA sequences of internal transcribed spacer regions (ITS 1 and 4) showed that the postharvest stem rot of kohlrabi was caused by Sclerotinia sclerotiorum. This is the first report of postharvest stem rot of kohlrabi in Korea.

• Mycobiology
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• 제39권1호
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• pp.52-53
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• 2011

Gray mold of blueberry caused by Botrytis sp. is reported for the first time in Korea. A detailed description of the fungus is given, along with its rDNA internal transcribed spacer sequence. The fungus was identified as Botrytis cinerea based on mycological characteristics and molecular data.

• Mycobiology
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• 제39권2호
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• pp.140-142
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• 2011

Soft rot in apple caused by Rhizopus oryzae was found for the first time in Korea. A detailed description of the specimen is given along with its internal transcribed spacer rDNA sequence. The fungus was identified as Rhizopus oryzae based on the mycological characteristics, molecular data, and pathogenicity testing.

• The Plant Pathology Journal
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• 제33권6호
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• pp.572-581
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• 2017

Anthracnose of papaya fruit caused by the fungus Colletotrichum gloeosporioides is one of the most economically important postharvest diseases. Hot water immersion (HW) and calcium chloride (Ca) treatments have been used to control papaya postharvest diseases; however, the effect of the combination HW-Ca on the pathogen growth and the development of the disease in infected papaya fruit has been scarcely studied. The aim of this study was to evaluate the effect of the HW-Ca treatment on the in vitro growth of C. gloesporioides conidia and the quality of infected papaya. In vitro, the HW-Ca treated conidia showed reduced mycelial growth and germination. In vivo, the HW-Ca treatment of infected papaya delayed for 5 days the onset of the anthracnose symptoms and improved the papaya postharvest quality. The combined treatment HW-Ca was better than any of the individual treatments to inhibit the in vitro development of C. gloeosporioides and to reduce the negative effects of papaya anthracnose.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.87.3-88
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• 2003

TiO$_2$photocatalytic ozonation was attempted to disinfect fungal pathogens causing postharvest spoilage of kiwifruits and to decompose fungicide residuals on kiwifruits. TiO$_2$Photocatalytic ozonation process synergistically degraded organic compound and inhibited conidial germination of the fungal pathogen compared to single treatment of ozonation or photocatalysis. The efficient control of fungal spoilage and degradation of residual fungicide on kiwifruits indicate that TiO$_2$photocatalytic ozonation is a very attractive method for postharvest disease control of kiwifruits as an alternative to fungicides application.

• The Plant Pathology Journal
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• 제28권1호
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• pp.114-114
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• 2012

• 식물병연구
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• 제9권4호
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• pp.229-236
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• 2003

사과 푸른곰팡이병을 방제하기 위하여 사과, 배, 복숭아 등 370점의 과일을 채취하여 과일표면으로부터 세균 1,080균주를 분리하였다. 분리한 1,080균주를 공시 하여 사과 저장병을 일으키는 Penicillium expansum, Alternaria alternata 그리고 Botrytis cinerea을 대상으로 항균활성 및 병 진전억제효과를 검정하여 8종의 길항세균을 선발하였다. 이 들 길항세균에 대한 세균학적 특성과 Biolog system에 의한 영양원 이용성을 조사한 결과 Bacillus amyloliquefaciens가 2균주, B. megaterium, B. subtilis var. gladioli, B. licheniformis， B. pumilus 및 Serratia marcescens로 동정하였다. Glucose, mannose, starch 등 8종의 탄소원을 공시하여 병원균의 생장 및 길항균의 중식에 미치는 영향을 조사한 결과, 병원균의 증식을 억제하고 길항균의 증식을 촉진하는 영양원으로 glucose가 선발되었다. 길항균의 처리효과를 높이기 위하여 길항균 현탁액에 glucose를 1% 첨가하여 사과에 처리한 다음 푸른곰팡이 병균을 $10^5$포자/ml 농도로 처리하였을 때, 병 진전억제효과가 S. marsecens P76-9처리에서 48%, B. amyloliquefaciens P43-2 처리에서 46% 그리고 B. licheniformis P94-1 처리에서 14% 증가되었다. 사과표면의 상처부위에서 처리한 길항균의 밀도변동에 있어서는 Bacillus 속 세균인 B. amyloliquefaciens P43-2과 B. licheniformis P94-1는 처리 후 7일까지 밀도가 증가하다가 처리 후 10일부터는 감소되는 경향이었으며, S. marsecens P76-9는 초기(처리 후 4일)에는 밀도가 감소되다가 처리 후 7일부터 증가되어 처리 후 7일까지도 일정한 수준으로 밀도가 유지되었다.

• The Plant Pathology Journal
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• 제36권2호
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• pp.133-147
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• 2020

Hexanal, a C-6 aldehyde has been implicated to have antimicrobial properties. Hence, this study was conducted to determine the antifungal activities of hexanal vapor against major postharvest pathogens of banana viz., Colletotrichum gloeosporioides and Lasiodiplodia theobromae. The pathogens were cultured in vitro and exposed to hexanal vapor at 600, 800, 1,000 and 1,200 ppm. Mycelial growth of both fungal pathogens were inhibited completely at 800 ppm and the incidence of anthracnose and stem-end rot diseases reduced by 75.2% and 80.2%, respectively. The activities of peroxidase, polyphenol oxidase, phenylalanine ammonia-lyase and glucanase had transiently increased in hexanal vapor treated banana by 5 to 7 days and declined thereafter. Postharvest treatment of banana with hexanal vapor resulted in phospholipase D inhibition and also resulted in cell wall thickening of the treated fruit, which impeded the penetration of the pathogenic spores. This was further confirmed by scanning electron micrographs. The defense-related protein intermediaries had increased in hexanal vapor treated banana fruit, which suggests induced resistance against C. gloeosporioides and L. theobromae, via., the phenylpropanoid pathway which plays a significant role in hindering the pathogen quiescence. Delayed ripening due to inhibition of phospholipase D enzyme, inhibition of mycelial growth and induced systemic resistance by defense enzymes collectively contributed to the postharvest disease reduction and extended shelf life of fruit.