At present,people usually spray triadimefon against wheat powdery mildew.Spraying on leaf segments in vitro may be a good way to monitor the resistance of wheat powdery mildew to triadimefon.To set up the monitoring standard of this method,the isolates of Blumeria graminis f.sp.tritici were isolated from Henan and Hebei province,and the sensitivity of 101 isolates to triadimefon were tested with leaf treatment and detached leaf segment methods in 2013.The results showed that the EC50 value to triadimefon di...