Monitoring for the Resistance of Botrytis cinerea Causing Gray Mold Against Mepanipyrim

Abstract With 86 isolates of Botrytis cinerea obtained from diseased fruits of tomato, strawberry andcucumber, it was conducted to detect the fungicide resistance of B. cinerea against mepanipyrim through anagar dilution method. FGA medium was used for monitoring the resistance. Among 86 isolates of B. cinerea,resistant isolates were composed by 23.3%, which was different according to regions isolating the pathogen.In accordance with isolation region, the isolation frequency of resistant isolates was as follows; that ofGyeonggi, Gyeongnam/Pusan and chungnam was 28.6%, 33.3% and 12.8%, respectively. The resistant isolatesof B. cinerea showed the cross resistance between mepanipyrim and pyrimethanil. Also the pathogenicity ofB. cinerea resistant to mepanipyrim was high as like that of sensitive isolates. Because of them, it should benecessary to manage the spraying system of mepanipyrim and the monitoring for the fungicide resistance.Key words Botrytis cinerea, fungicide resistance, mepanipyrim, cross resistance