경기 지역 오이 흰가루병균(Sphaerotheca fusca)의 살균제 저항성 검정 |
김진영, 홍순성, 임재욱, 박경열, 김홍기 |
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Screening of Fungicide Resistance of Cucumber Powdery Mildew Pathogen, Sphaerotheca fusca in Gyeonggi Province |
Jin Young Kim, Sun Sung Hong, Jae Wook Lim, Kyeong Yeol Park, Hong Gi Kim |
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Abstract |
Fungicide resistance of cucumber powdery mildew was screened among the pathogens isolated from diseased plants in main cucumber productuion areas in Gyeonggi Province. Each fungicide from different activity group for the control of powdery mildew were sprayed on cucumber leaves according to application concentration. Each conidia mixed with sterilized water isolated of pathogens were transferred on the cucumber leaf disks treated with each fungicide. At 7 to 9 days after inoculation of pathogen, disease severity was recorded under the microscope. Most of pathogen isolates showed moderate resistance to difenoconazole belonged to DMI group fungicide while some isolates from Osan were resistant even 300 μg/ml. Isolates from Pyeongtaek, Osan and Yongin area also showed moderate resistance to fenarimol while one isolate showed resistant to fenarimol even 300 μg/ml. Most of isolates from Pyeongtaek, Osan and Yongin showed highly resistant to azoxystrobin belonged to strobilurin group fungicide. Standard sensitive isolates the minimum inhibition concentration (MIC) value for azoxystrobin showed 200 μg/ml while resistance isolates showed above 2000 μg/ ml. Resistant isloates also showed cross resistance among strobilurin group fungicides and low control efficacy in the field test. These results suggest that treatment of strobilurin fungicides should be reduced for the control of powdery mildew. |
Key Words:
Cucumber, DMI, Powdery mildew, Resistance, Strobilurin |
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