• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.668-675
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• 1998

These surveys were conducted to check the occurrence of disease in various horticultural crops in alpine areas, especially Daekwallyong areas, Pyongchang-Gun, and Hyeongseong-Gun in Kangwon province. TuMV on Chinese cabbage was one of the most serious diseases, especially in 1994 and 1997. The incidence of soft rot and clubroot has been increased gradually. Brittle root rot on Chinese cabbage was significantly decreased. Soft rot, gray mold, downy mildew, powdery mildew, bottom rot and Alternaria leaf spot were the common diseases on most vegetable crops. Gray mold (Botrytis cinerea) on celery, cercospora leaf spot (Cercospora sp.) on melon, powdery mildew (Erysiphe cichoracearum) on lettuce, and clubroot (Plasmodiophora brassicae) on parsley are newly found in Korea. The most common and predominant diseases were viruses, especially CMV, TMV, TuMV, BBMV, and gray mold, wilts, and cercospora leaf spot on many flowers in alpine areas. Fusarium oxysporum f. sp. eustomae causing wilting on lisianthus (Eustoma grandiflorum), Turnip mosaic virus causing mosaic and color breaking on stock, Cercospora spp. causing cercospora leaf spot on various wild lily, Cladosporum echinulatum causing leaf spot on carnation, and phytoplasma causing witches' broom on statice (Limonium sinuatum) and blazing star (Liatris spp.) were newly found during these surveys in Korea.

• Horticultural Science & Technology
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• v.34 no.4
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• pp.626-633
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• 2016

The objective of this study was to assess the effect of precooling and application of gaseous $ClO_2$ on the retention of freshness and quality of 'Maehyang' strawberry fruits intended for export. 'Maehyang' strawberry fruits (Fragaria ${\times}$ ananassa Duch.) were grown in commercial greenhouses and then harvested. Fruits of uniform and medium size at 60% ripeness were selected and assigned to one of four treatment groups: non-treatment (control), precooling only (PO), gaseous $ClO_2$ only (GCO) or precooling combined with gaseous $ClO_2$ (P + C). Weight loss was lowest in the PO treatment and greatest in the GCO treatment after export. Compared to the control and PO treatment groups, strawberry fruits in the GCO treatment group maintained high brightness and high chroma. Six days after shipping, fruits in the P + C treatment group had the highest soluble solids content, even as high as $10.05^{\circ}Brix$; the lowest value was observed in the PO treatment. The incidence rate of gray mold in strawberry fruits was 20% and 17% in the control and the PO treatment, respectively; in the GCO treatment, the incidence rate of gray mold amounted to 10%. No gray mold was observed in the P + C treatment group. These results indicate that gaseous $ClO_2$ treatment combined with precooling (P + C) was effective in maintaining the freshness of 'Maehyang' strawberry fruits intended for export from South Korea to Hong Kong.

• The Plant Pathology Journal
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• v.15 no.3
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• pp.162-167
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• 1999

Integration of microbial antagonists with fungicides was tried to control the gray mold caused by Botrytis cinerea on pepper in greenhouse conditions and to reduce fungicide uses. All of the selected bacterial antagonists, Bacillus amyloliquefaciens BL3, Paenibacillus polymyxa BL4, and Pseudomonas putida Cha94, completely inhibited the conidial germination of B. cinerea until 30 days after treatment. However, bacterial colonization of pepper phylloplane was poor in BL4, while the other bacterial isolates and the fungal antagonist Trichoderma harzianum TM colonized well on the phylloplane, maintaining the population density of 104-105 cfu/g until 15 days after microbial treatments. Out of 13 kinds of selected fungicides used for gray mold diseases, polyoxin B and BKF 1995 showed the most discriminatory activity on the fungal growth between B. cinerea and TM. TM grew readily on the media containing those fungicides, while B. cinerea showed poor or no mycelial growth on them. The selected fungicides and antagonists alone reduced incidence of gray mold on pepper, showing disease indices of about 2.4 to 3.0, while its was increased up to 4.2 in the untreated control. Alternate treatments with the antagonists and 2-fold diluted fungicides inhibited the disease incidence as much as the antagonists or fungicides alone, and reduced the secondary inoculum more than the single treatments. This suggests that integration of antagonists and fungicides may be an efficient way to reduce fungicide sprays with reliable control efficacy of the disease. However, there was not much difference in the early and mid-term disease progress among the treatments and the untreated control, probably due to extremely favorable environmental conditions for the disease development in this experiment.

• Research in Plant Disease
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• v.18 no.3
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• pp.217-224
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• 2012

Post-harvest rot of grape causes a severe economic loss and lower of the grape quality. It is also one of the important limiting factors for grape export. Grape rots and their casual agents on 'Red Globe' variety imported from Chile were identified. Grapes shown rotting symptom were collected from the storages near the import harbor. The 3 different rots were identified on the imported 'Red Globe'; melting decay, gray mold, and blue mold. A bacterium that isolated from a typical melting decay symptom was identified as Gluconobacter cerinus on basis of its nucleotide sequence of 16S rDNA and fatty acid profile. By inoculation on grape, it caused cracking and dissolution of epidermis of grape which were the characteristics of melting decay. Botrytis cinerea and Penicillium expansum were isolated from grapes showing gray mold and blue mold. The 2 fungal isolates were identified on basis of their morphological characteristics and nucleotide sequence of their beta-tubulin genes. They showed strong pathogenicity on 'Campbell Early' variety that is a major table grape in Korea.

• 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 Korean Journal of Mycology
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• v.41 no.1
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• pp.38-41
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• 2013

In 2010 and 2011, gray mold was found on common fig (Ficus carica) fruit grown at the research field of Jeollabuk-do Agricultural Research and Extension Services, Korea. Gray mold symptoms on common fig fruit mainly occurred after harvest season until December. The typical symptom included brown water-soaked rot and fruit decay. The diseased fruit was covered by gray to brown colored conidiophore and conidia. The conidiophores were tree shape and measured $15-33{\times}2{\mu}m$. Conidia on conidiophore were ellipsoidal or lemon shape, colorless, single cell, and measured $7.3-14.6{\times}6.8-11.1{\mu}m$. The nucleotide sequences of the rDNA ITS region obtained from the pure culture of the gray mold on common fig were 100% similar to the sequences of the GenBank accession number HQ171052, EU519210, HQ171053, FN812726, HM849615, and EU563120 of B. cinerea isolates. In phylogenetic tree, the representative isolate was placed within same clade of B. cinerea. Based on the morphological characteristics and analysis of rDNA ITS sequence data, the fungus was identified as B. cinerea.

• The Plant Pathology Journal
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• v.17 no.6
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• pp.384.3-384
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• 2001

• The Plant Pathology Journal
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• v.17 no.6
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• pp.385.1-385
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• 2001

• The Plant Pathology Journal
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• v.17 no.6
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• pp.384.4-385
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• 2001

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2002.11a
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• pp.49.1-49
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• 2002