• Research in Plant Disease
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• v.12 no.3
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• pp.249-253
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• 2006

Several fungicides such as polyoxine B, fludioxonil, tebuconazole, tebuconazole+dichlofluanid, and fenbuconazole were sprayed once a week on roses in greenhouse. Botrytis infection on stalks was reduced by 71-89% after regular fungicide spray. The reduction of conidial inoculum by these treatments is also observed. The rose petal infections were controlled significantly by these fungicides only 2 days after the application. The development of gray mold on rose flowers harvested just after spray of fludioxonil, tebuconazole and tebuconazole+dichlofluanid were reduced compared to untreated control. This beneficial effect was also shown in flowers artificially inoculated with B. cinerea conidia after harvest. Post-harvest treatments by spraying cut flowers with the fungicides such as iprodine plus thiram, tebuconazole+dichlofluanid and polyoxin D reduced disease incidence by 50-55%.

• The Korean Journal of Mycology
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• v.41 no.3
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• pp.172-180
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• 2013

Grey mold infection rate in tomato was investigated with the inoculation of dead flowers on Botrytis selective media. The grey mold infection rate of flower after fruiting were higher in the order of after 45 days, after 25 days, and fruiting day with 100%, 87% and 65%, respectively. The number of infected flowers were increased with time increase after the flowering before fruiting. BSM (Botrytis selective medium) was used to check grey mold infection rate depending on the flowering stage and cultivar. Grey mold infection rate depending on the flowering stage was similar in all the beef-tomato cultivar as 1.5~5% at preflowering, 1.5~45% at flowering and 75~90% at fruiting. On the other hand, cherry tomato cultivar "KoKo" had lower infection rates of 0~3.5% at pre-flowering, 10~30% at flowering and 20~50% at fruiting. These resulted from the fact that beaf-tomato cultivar have much bigger flowers and larger amount of pollens compared to those of cherry tomato cultivar. The amounts of falling pollens of Botrytis spp. were checked for beaf-tomato cultivar and cherry tomato cultivar using BSTM. The amounts of falling pollens were increased as growth period was extended, and the amount of spores increased rapidly during the outbreak of grey mold. Twelve field trials in Buyeo and Iksan areas showed that Fluazinam, and Diethofencarb+Carbendazim were effective fungicides to control tomato grey mold, and these results were similar to those of field trials with BSTM. This is the first report of Fluazinam as a effective fungicide for the control of grey mold of tomato even though it has not been registered yet for the control of gray mold in tomato.

• Conservation Science in Museum
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• v.7
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• pp.25-31
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• 2006

We performed the conservation treatment for Bigyeokchinjeonnoe (A kind of time bomb in the Joseon Dynasty) excavated from Hwawangsanseong Fortress in Changnyeong-gun, Gyeongsangnam-do Province. Part of the Bigyeokchinjeonnoe has been lost; we did not restore the lost part so that one can observe the inside through it. The results of X-ray investigation and C. T (Computed Tomography) scan proved the generation of many blowholes around the molding line during the casting process; a hole in the casting mold to maintain inner mold during casting was identified on the surface and traces of fortifying this part with iron plate were also identified. The main ingredients of the blue corrosion on the surface were identified as O, Fe, P, Si and Al by SEM/EDS analysis. The result of XRD analysis identified the blue corrosion as vivianite [Fe₃(PO₄)₂·8H₂O]. The metal structure clarified its material was gray cast iron.

• Journal of Microbiology and Biotechnology
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• v.8 no.5
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• pp.490-496
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• 1998

Random amplified polymorphic DNA (RAPD) markers were used to survey genetic variability among 34 Botrytis cinerea isolates from nine different host plants in Korea. For RAPD analysis, 115 arbitrary decamer primers were initially screened for polymorphic major DNA bands with 11 representative B. cinerea isolates. Eleven primers that initially detected polymorphisms were tested a second time with additional 23 isolates of B. cinerea as well as one isolate of Botrytis squamosa as an outgroup. The RAPD analyses revealed that all isolates except one showed different molecular phenotypes. Dendrograms obtained from dissimilarity matrices using the unweighted paired group method of arithmetic means (UPGMA) showed the 36.4% to 90.0% similarity among all B. cinerea isolates. The B. squamosa isolate showed the least similarity to all B. cinerea isolates. The cluster analyses indicated no correlation among all the characteristics examined including molecular phenotypes, host and geographic origins, year of isolation, or pathogenicity. The RAPD data suggest that a high level of genetic variation exists among Korean populations of B. cinerea and it seems to be caused by heterokaryosis among preexisting molecular phenotypes.

• Korean Journal of Organic Agriculture
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• v.5 no.1
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• pp.137-147
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• 1996

For the purpose of acquiring microbial agents that can be utilized to biologically control the major airborne diseases to apple trees, such as canker(Botryosphaeria dothidea), bitter rot(Glomerella cingulata), alternaria leaf spot(Alternaria mali), root rot(rosellinia necatrix), canker(Valsa ceratosperma) and gray mold rot(Botrytis cinerea), the effective microorgaisms were isolated, tested for antagonistic activity to the pathogens causing major diseases to apple trees and identifed. Screening of more than 5,000 species of microorganisms collected in nature for them antagonistic action to the pathogens causing 5 major diseases to apple trees resulted in selection of effective species. Out of the 11 species, one species designated as CAP134 demonstrated outstanding activity. The bacterial strain, CAP134 exerted antagonistic efficiency of 57% on an isolated strain and 40% on a donated strain of Botryosphaeria dothidea., 52% on an isolated strain and 46% on a purchased strain of Alternaria mali, 60% on Valsa ceratosperma 25% on Glomerella cingulata, and 64% Rosellinia necatrix. The CAP134 was identified as a bacterial strain to Bacillus subtilis ATCC 6633 based on morephology, culture conditions, and physio-biochemical characteristics.

• 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.2
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• pp.97-102
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• 2007

A total of 39 essential oils were tested for antifungal activities as volatile compounds against five phytopathogenic fungi at a dose of 1 ${\mu}l$ per plate. Five essential oils showed inhibitory activities against mycelial growth of at least one phytopathogenic fungus. Origanum vulgare essential oil inhibited mycelial growth of all of the five fungi tested. Both Cuminum cyminum and Eucalyptus citriodora oils displayed in vitro antifungal activities against four phytopathogenic fungi except for Colletotrichum gloeosporioides. The essential oil of Thymus vulgaris suppressed the mycelial growth of C. gloeosporioides, Fusarium oxysporum and Rhizoctonia solani and that of Cymbopogon citratus was active to only F. oxysporum. The chemical compositions of the five active essential oils were determined by gas chromatography-mass spectrometry. This study suggests that both E. citriodora and C. cyminum oils have a potential as antifungal preservatives for the control of storage diseases of various crops.

• The Plant Pathology Journal
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• v.34 no.3
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• pp.241-249
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• 2018

Commercial biocontrol of microbial plant diseases and plant pests, such as nematodes, requires field-effective formulations. The isolate Pseudomonas chlororaphis O6 is a Gram-negative bacterium that controls microbial plant pathogens both directly and indirectly. This bacterium also has nematocidal activity. In this study, we report on the efficacy of a wettable powder-type formulation of P. chlororaphis O6. Culturable bacteria in the formulated product were retained at above $1{\times}10^8$ colony forming units/g after storage of the powder at $25^{\circ}C$ for six months. Foliar application of the diluted formulated product controlled leaf blight and gray mold in tomato. The product also displayed preventative and curative controls for root-knot nematode (Meloidogyne spp.) in tomato. Under laboratory conditions and for commercially grown melon, the control was at levels comparable to that of a standard commercial chemical nematicide. The results indicated that the wettable powder formulation product of P. chlororaphis O6 can be used for control of plant microbial pathogens and root-knot nematodes.

• Research in Plant Disease
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• v.10 no.1
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• pp.1-7
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• 2004

The year of 2003 was characterized as a cool humid year. Low temperature and frequent rains were continued during March to July, resulting in 1.6 times higher rainfalls and 32％ less sunshine period compared to the average yean Due to 2003's climatic condition, rice blast, and bacterial leaf blight occurred severely. Higher rainfalls caused severe epidemic of phytophthora disease and, in case of red-pepper, 55％ of cultivation acreage was devastated by the disease over the country. Besides, crop diseases which become severe under cool-humid conditions, such as gray mold, sclerotinia rot, downy mildew, increased significantly compared to the previous year. In fruit trees, brown spot of apple, and pear scab occurred severely causing much yield loss.

• Research in Plant Disease
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• v.24 no.1
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• pp.1-8
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• 2018

Bacterial diseases such as bacterial canker and bacterial leaf spot and fungal diseases such as gray mold, powdery mildew, side rot and leaf spots are major diseases damaging leaves of kiwifruit in Korea. In this review, we summarize symptoms and epidemiological characteristics of the major bacterial and fungal leaf diseases of kiwifruit and propose proper control methods of the diseases that can be practically utilized at the farmers' kiwifruit orchards in order to prevent the diseases on the basis of our research works and field experiences and important research products conducted during the last three decades in the world.