2011年我国主要麦区小麦白粉病菌群体对三唑酮和苯锈啶的敏感性

 小麦白粉病(Wheat Powdery Mildew)是我国小麦生产上常发性病害之一^1]。小麦白粉病的防治主要采用抗病品种和化学药剂,辅之以栽培措施的综合防治技术。由于目前生产上抗病品种相对缺乏,药剂防治成为我国小麦白粉病防治的主要措施之一^2]。自20世纪80年代以来三唑类杀菌剂一直是我国防治小麦白粉病的主要药剂,由于长期、大范围、单一的使用导致小麦白粉病菌对三唑类杀菌剂的抗药性大大提高。监测结果表明,2009年我国小麦白粉病菌群体对三唑酮的平均抗性水平已经达到56.58倍,抗性频率达到99.09%,其中高抗菌株占49.09%^3]。目前小麦白粉病菌对三唑酮的抗性形势十分严峻,寻找三唑类杀菌剂的替代药剂成为控制该病害的迫切需求。

Sensitivity of Blumeria graminis f.sp.tritici isolates to triadimefon and fenpropidin in China in 2011

The sensitivity of 100 isolates of Blumeria graminis f. sp. tritici sampled from eight provinces or cities to triadimefon and fenpropidin was tested by seed treatment and detached leaf segment methods. The results showed that the mean EC₅₀ of all the tested isolates to triadimefon was 47.27 mg/L, and the mean resis-tance factor (RF) was 22.62. The frequency of resistant isolates to triadimefon reached 97.00%. The resistance factor of the tested isolates from Shandong to triadimefon was the highest, reached 52.63. The base-line of sensitivity of B. graminis f. sp. tritici to fenpropidin was 100.47 mg/L. There was no significant cross-resistance between triadimefon and fenpropidin in B. graminis f. sp. tritici population. These results will provide the refe-rence for fungicide resistant management and the rational use of fungicides.