河南省小麦纹枯病菌及小麦全蚀病菌对丙环唑的敏感性

Sensitivity of Rhizoctonia cerealis and Gaeumannomyces graminsis isolates from Henan Province to propiconazol

小麦纹枯病和小麦全蚀病是河南省小麦生产上重要的土传病害,发病面积分别在300万和30万hm2[1,2]。近年来,由于小麦高产栽培措施（早播、密植、高肥）的推广,以及气候条件适宜、农机跨区作业等原因,两种病害的发生面积日益增大,

The sensitivity of Rhizoctonia cerealis and Gaeumannomyces graminsis to propiconazol was determined by measuring the mycelial growth on the fungicide-amended media using 98 isolates of R. cerealis and 88 isolates of G. graminsis from Henan Province. The results indicated that 50% effective concentration（EC50） values of R. cerealis and G. graminsis to propiconazol ranged from 0.119 3 to 2.581 3,0.001 5 to 0.172 4 μg ·mL-1,respectively. The results of the frequency analysis revealed that lowsensitivity subcolony to propiconazol had been discovered in R. cerealis and G. graminsis. The mean EC50 values of（0.484 8±0.200 9） and（0.049 3±0.029 0） μg·mL-1for most isolates showed a unimodal curve distribution,which were treated as the sensitivity baseline of R. cerealis and G. graminsis to propiconazol,respectively. The isolates collected from different regions showed different sensitivities. The results provided a theoretical basis for the efficient application of propiconazol in the control of wheat sharp eyespot and take-all in the field of Henan Province.