• Research in Plant Disease
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• v.13 no.3
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• pp.191-196
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• 2007

An isolate of Ampelomyces quisqualis 94013(AQ94013) was selected as an effective agent for biological control against cucumber powdery mildew. In order to develop mass production technique, six cereal media made with barley, rice, mille and brown rice, sorghumand rice seed were tested. Among them, barley medium was the best for the growth and conidial production of AQ94013. Optimum temperature for the mass production of AQ94013 was $25^{\circ}C$ and followed by $20^{\circ}C$ and $30^{\circ}C$. Light radiation inhibited conidial production of AQ94013 since number of conidia formed on barely medium under continuous light or 12 hrs alternative light were much less than cultured in darkness. Tthe conidia produced on the medium at $30^{\circ}C$ maintained the parasitic ability to Sphaerotheca fusca for 30 days. A culture method of AQ94013 in barley liquid medium with adding barely power(40 g/l) in darkness for five days at $25^{\circ}C$using a 30 l-fermenter was very effective for mass production of conidia.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1999.04a
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• pp.35.1-35
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• 1999

• The Plant Pathology Journal
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• v.17 no.6
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• pp.370.2-370
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• 2001

• Research in Plant Disease
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• v.15 no.3
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• pp.209-216
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• 2009

During the period of June, 2005 to May, 2008, 44 host plants infected with powdery mildew were collected in the Jeon-ju and Jang-su districts of Jeonbuk province and in the Jang-sung district of Jeonnam province. The hyperparasites, Ampelomyces were confirmed in 12 plant species. Most of the pycnidium shapes of Ampelomyces were circular or oval shaped, and the sizes were different even within the same host plant, and also the color of pycnidium was ranged from light brown to dark brown. Ampelomyces species were isolated from 4 hosts including Impatiens balsamina L., Cucurbita pepo, Rudbeckia laciniata var. elatier and Youngia sonchifolia, and thus the most appropriate 12 Ampelomyces strains for the current experiment were selected. When analyzing the selected 12 strains' incubational and nutritional characteristics, the malt extract agar was the most appropriate media. When investigating the effect of osmotic pressure on the spore germination, 0.15M NaCl concentration was the optimum germination concentration. When the isolated Ampelomyces sp. was tested in-vitro, it was found to be effective to control in other plant pathogens, isolated Ampelomyces showed no pathogenicity to the plant. strains isolated . studied on rDNA ITS sequence analysis. The rDNA ITS sequence data of Ampelomyces sp. isolate BSLAH16 from Impatiens balsamina L. were analyzed and identified.

• The Korean Journal of Mycology
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• v.35 no.2
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• pp.115-120
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• 2007

Powdery mildew caused by Podosphaera fusca is one of the most important diseases in leafy lettuce (Lactuca sativa L.). Since the disease has been a threat to safe cultivation of leafy lettuce, its control methods have to develop to produce good quality of lettuce for farmer and consumer. Occurrence of lettuce powdery mildew is increasing more and more due to continuous cultivation of lettuce all through the year, non-removal of diseased plant parts of lettuce, spray of inadequate fungicides by mistaken acknowledge of lettuce powdery mildew for lettuce downy mildew, etc. The control effect of five fungicides against lettuce powdery mildew was examined in a plastic greenhouse located in Suwon. When fungicides were sprayed three times at 10 days-intervals in the early stage of occurrence of powdery mildew, the incidence of powdery mildew in the plants treated with kresoxim-methy SC, azoxystrobin SC, Ampelomyces quisqualis AQ94013 WP, Paenibacillus polymyxa AC-1 SC and Bacillus subtilis Y 1336 WP was 0.7%, 0.7%, 26.0%, 36.7% and 42.0%, respectively, whereas the incidence of non-treated control was 55.3% on eight days after final application. Phytotoxicity of five fungicides tested was not observed in lettuce seedling plants.

• Mycobiology
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• v.37 no.4
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• pp.308-309
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• 2009

Powdery mildews on over 40 plants in Bangalore were screened during July-December of 2003~2008. Isolates from mycoparasitised Oidium caesalpiniacearum of Bauhinia purpurea comprised Lasiodiplodia theobromae, in addition to Ampelomyces quisqualis. Koch's postulates were satisfied to establish the mycoparasitism of L. theobromae. This is the first report that L. theobromae acts as a mycoparasite of a powdery mildew.

• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.413-420
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• 2013

The purpose of this study was to evaluate the control efficacy of major environment-friendly control agents against powdery mildew, as affected by the application condition such as disease-developing stage and microclimate, as compared with the efficacy of pesticides in plug seedling of three Cucurbitaceae vegetables, including cucumber, melon, and oriental melon. Single or combined application of major six environment-friendly control agents was used in the experiment: two biofungicide (Ampelomyces quisqualis 94013 and Bacillus subtilis Y1336), two plant extracts (neem oil and extracts of Rheum undulatum), and two mineral materials (wettable sulfur powder and lime bordeaux mixture). These control agents were treated to the plug seedlings for preventing powdery mildew and curative applications for managing powdery mildew. In all treatments, the disease incidence declined as daily average temperatures increased to $30^{\circ}C$ for consecutive 6~8 days with maximum temperature over $40^{\circ}C$. In preventative application, the control efficacy against powdery mildew was the highest in the treatment of wettable sulfur powder, and lowest in the B. subtilis Y1336, with values of 20~40%. In cucumber seedlings, the preventive single application of neem oil or wettable sulfur powder was more effective than curative application of fungicides, while the control efficacy of these agents was similar to those of fungicides in melon seedlings. The single application of R. undulatum extracts was also effective in preventing the disease for both cucumber and melon seedlings, showing a higher control efficacy than those of biofungicides during seedling stage. The treatment of water spray was not effective and showed a higher disease incidence than the untreated control plot in the oriental melon and melon seedlings. The curative application with environment friendly control agents, after powdery mildew was first detected, could not successfully controlled the disease at the middle stage (5~10% of disease incidence) of disease development. The curative combined application of [R. undulatum extracts (1st application) + wettable sulfur powder (2nd) + neem oil (3rd)] showed the highest control efficacy among the other treatments, with control value over 80% at the early stage (less than 1% of disease incidence) of disease development.