• Animal cells and systems
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• v.9 no.1
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• pp.37-40
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• 2005

In okra Macrophomina phaseolina and Furasium verticilloides cause collar-rot, seedling-rot and other severe diseases at fruit maturing stages. These stages were located in all the components of the seeds. The seeds collected from seeds infected with Macrophomina phaseolina and Fusarium verticilloides revealed 100% infection. Such seeds resulted in pre- and post-emergence mortalities. Inoculated seeds also showed pre- and post-emergence death of the seedlings. The fungi seed-transmitted showed disease symptoms at different growth of okra plant. Fusarium verticilloides causes the wilt and Macrophomina phaseolina causes the collar-rot. Until now seed transmission of these fungi have not been studied. Hence, in the present study an attempt has been made to fill this lacunae.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.25-27
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• 2003

Since 1993, a total of 50 problematic plant diseases unrecorded in Korea were surveyed in Gyeongnam province. Totally 34 new host plants to corresponding pathogens investigated in this study were 5 fruit trees, 9 vegetables, 12 ornamental plants, 3 industrial crops, and 5 medicinal plants. Among the newly recorded fruit tree diseases, fruit rot of pomegranate caused by Coniella granati and Rhizopus soft rot of peach caused by Rhizopus nigricans damaged severely showing 65.5% and 82.4% infection rate. Among the vegetable diseases, corynespora leaf spot of pepper caused by Corynespora cassiicola and the crown gall of pepper caused by Agrobacterium tumefaciens, powdery mildew of tomato caused by Oidiopsis taurica were the most severe revealing 47.6%, 84.7%, and 54.5% infection rate in heavily infected fields, respectively. In ornamental plants, collar rot of lily caused by Sclerotium rolfsii, gray mold of primula caused by Botrytis cinerea, soot leaf blight of dendrobium caused by Pseudocercospora dendrobium, sclerotinia rot of obedient plant caused by Sclerotinia sclerotiorum showed 32.7 to 64.8% disease incidence. On three industrial plants such as sword bean, broad bean, and cowpea, eight diseases were firstly found in this study. Among the diseases occurring on broad bean, rust caused by Uromyces viciae-fabae and red spot caused by Botrytis fabae were the major limiting factor for the cultivation of the plant showing over 64% infection rate in fields. In medicinal plants, anthracnose of safflower caused by Collectotrichum acutatum was considered the most severe disease on the plant and followed by collar rot caused by Sclerotium rolfsii.(중략)

• The Plant Pathology Journal
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• v.23 no.3
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• pp.166-173
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• 2007

In a trial to select suitable fungicides for developing a spray program that can control apple white rot effectively, after-infection activities in some protective fungicides were detected. Six fungicides, mancozeb, propineb, benomyl, folpet, azoxystrobin and iminoctadine-triacetate, which had been extensively used in apple orchards, were sprayed on 12-year-old apple trees (cv. Fuji) at 15-day intervals from late May to late July. Disease incidences and infection frequencies of the fruit bagged just before and soon after each spray were examined. When the infection frequency or disease incidence of the fruit bagged after each spraying of fungicide was significantly lower than those of the fruit bagged before spraying, the fungicides appeared to confer after-infection activity. The six fungicides showed diverse activities on white rot: folpet showed after-infection activity on disease development, iminoctadine-triacetate showed after-infection activity on infection, azoxystrobin showed after-infection activity on disease development and infection, and mancozeb, propineb and benomyl showed no distinct activity. The activity of a fungicide became much higher when it was sprayed alternately with other fungicide rather than successive spraying of the same fungicide. Analysis of the properties of these protective fungicides could lead to the development of a highly effective spray program against white rot.

• Research in Plant Disease
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• v.26 no.1
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• pp.48-52
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• 2020

In July 2019, typical rot symptom was observed on peach fruits harvested from the fields at Andong, Korea. As the disease progressed, white and purple colored mycelial mat developed on the surface of the infected fruits. A causal pathogen was isolated from the infected fruit and cultured on potato dextrose agar media for identification. Fungal colonies on potato dextrose agar produced 3 pigments, including purple, yellow, and white colors. The isolate incited fruit rot symptoms on artificially inoculated peach fruits, from which the same fungus was isolated, fulfilling Koch's postulates. Based on the morphological characteristics and sequence analysis of rDNA internal transcribed spacer, translation elongation factor 1-alpha, and β-tubulin, the causal agent of the disease was identified as Fusarium avenaceum. This study is the first report of fruit rot of peach fruits caused by Fusarium avenaceum in Korea.

• The Korean Journal of Mycology
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• v.42 no.4
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• pp.353-356
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• 2014

In August 2013, brown rot was observed on cherry fruits (Prunus avium L.) in Hwaseong city, Korea. Fruit rot first appears as small, circular brown spots that increase rapidly in size causing the entire fruit to rot. Grayish spores appear in tufts on rotted areas. Based on these morphological characteristics, the two isolates were identified as Monilinia fructicola. Molecular analysis of 5.8S subunit and flanking internal transcribed spacers (ITS1 and ITS2) was performed to confirm the identification. The ITS sequences had 100% identity with those of other reference M. fructicola isolates of NCBI GenBank. Pathogenicity was tested using spore suspension inoculation on wounded or unwounded cherry fruits. The lesions were observed on wounded and unwounded fruits after inoculation for 7 days. This is the first report on M. fructicola causing brown rot on cherry fruits in Korea.

• Mycobiology
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• v.46 no.2
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• pp.154-158
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• 2018

Bitter rot caused by the fungal genus Colletotrichum is a well-known, common disease of apple and causes significant yield loss. In 2013, six fungal strains were isolated from Fuji apple fruits exhibiting symptoms of bitter rot from Andong, Korea. These strains were identified as Colletotrichum fructicola and C. siamense based on morphological characteristics and multilocus sequence analysis of the internal transcribed spacer rDNA, actin, calmodulin, chitin synthase, and glyceraldehyde-3-phosphate dehydrogenase Pathogenicity tests confirmed the involvement of C. fructicola and C. siamense in the development of disease symptoms on apple fruits. This is the first report of C. fructicola and C. siamense causing bitter rot on apple fruit in Korea.

• The Korean Journal of Mycology
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• v.32 no.2
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• pp.130-133
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• 2004

Leaf blight and fruit rot of sweet persimmon (cv. Fuyu) caused by Pestalotia diospyri were observed during the growing season and postharvest such as storage and transport, respectively. Typical symptoms on leaves developed with small brown spots and were later reddish brown colors. In the storage fruit, the white mycelial mats formed between fruit and calyx. The pathogenic fungus was isolated from infected fruits and cultured on potato dextrose agar (PDA). Colony color of the fungus was white at first on PDA. Conidia were ovoid or fusiform, 5 cells, middle 3 cells were olive, upper and lower 2 cells were colorless, and their size were $16{\sim}22\;{\times}\;6{\sim}8\;{\mu}m$. They had were $2{\sim}3$ appendage at basal cell and size $9{\sim}18\;{\mu}m$. Based on the cultural and mycological characteristics and pathogenicity test on host plants and fruits, the fungus was identified as Pestalotia diospyri Syd.&P. Syd. This is the first report on the leaf blight and fruit rot of sweet persimmon caused by Pestalotia diospyri in Korea.

• The Korean Journal of Community Living Science
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• v.18 no.2
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• pp.241-246
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• 2007

This study was conducted to select and screen for an antifungal bacterial strain showing pathogen inhibitory activity against Diaporthe actinidiae, which causes stem-end rot in kiwi fruit. Four bacterial strains were isolated which strongly inhibit Diaporthe actinidiae from among two hundred and fifty bacterial strains screened from the soil where kiwi fruit were grown. By co-culturing bacterial strain #72 and the pathogen causing the stem-end rot of kiwi fruit, bacterial strain #72 showed 81.0% antifungal activity against Diaporthe actinidiae. Bacterial strain #72 was identified to be from the genus Bacillus sp. based on morphological and biochemical characterization. The bacterialization of culture broth for Bacillus sp. #72 which was sterilized at $121^{\circ}C$ for 15 minutes and than purified by $0.45{\mu}m$ membrane filter showed almost all of the antagonistic activity against Diaporthe actinidiae. We have also confirmed that in vitro treatment of Bacillus sp. #72 cultured in SD+B+P(sugar 5%, soy sauce 3%, beef extract 0.2%, peptone 0.2%) medium efficiently inhibited the growth of Diaporthe actinidiae responsible for stem-end rot in kiwi fruit.

• Research in Plant Disease
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• v.15 no.1
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• pp.51-53
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• 2009

The fruit rot of watermelon (Citrullus lanatus) occurred sporadically in the farmers field at Chojeondong, Jinju city, Korea, in 2007. The typical symptom was water-soaked, brown on the fruit, and than infected fruits were mostly rotted. White mycelial mats were spread over lesions, and then sclerotia were formed on fruit and near soil line. The sclerotia were globoid in shape, $1{\sim}3\;mm$ in size and white to brown in color. The optimum temperature for mycelial growth and sclerotia formation on PDA was $30^{\circ}C$ and the hyphal width was $4{\sim}8{\mu}m$. The typical clamp connections were observed in the hyphae of the fungus. On the basis of mycological characteristics and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii. This is the first report on the fruit rot of watermelon by S. rolfsii in Korea.

• Korean journal of applied entomology
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• v.24 no.3 s.64
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• pp.129-133
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• 1985

Effect of some physical and chemical factors on germination of conidia of Alternaria alternata (Fries) Keissler causing fruit rot of apple was investigated. The germination was maximum at $30^{\circ}C$, 100 per cent RH and at 5.5 pH Syllit, amongst the 11 fungicides and Planofix, amongst the 5 growth regulators caused maximum inhibition of conidial germination.