Monitoring of sensitivity of Rhizoctonia cerealis to jinggangmycin in Jiangsu,Henan,Anhui and Shandong Provinces

The sensitivity of Rhizoctonia cerealis populations collected in 1984,2001 and 2010 from Jiangsu Province to jinggangmycin was surveyed to monitor the trend in resistance of R.cereals,and the sensitivity of isolates collected from Shandong,Henan and Anhui Provinces were also surveyed in 2010.EC50 value of isolates in 1984 ranged from 0.31 to 0.87 μg/mL,from 0.05 to 1.21 μg/mL in 2001,and from 0.20 to 1.09 μg/mL in 2010.There was no significant difference in sensitivity of R.cerealis populations to jinggangmycin during 26 years in Jiangsu Province.EC50 value of isolates in Henan Province ranged from 0.15 to 1.16 μg/mL,from 0.09 to 1.33 μg/mL in Shandong Province,and from 0.43 to 0.90 μg/mL in Anhui Province.There was also no significant difference in sensitivity of isolates from four provinces in 2010.These results indicated that jinggangmycin can be used as major fungicide to control wheat sharp eyespot in future.