2002年部分麦区小麦白粉病菌对三唑酮的抗药性监测及苯氧菌酯敏感基线的建立

 采用拌种离体叶段法测定了2002年采自北京、江苏、山东、山西、河北、新疆和四川7省市部分麦区的109个小麦白粉病菌菌株对三唑酮和苯氧菌酯的敏感性,结果表明小麦白粉病菌群体对三唑酮敏感性EC₅₀平均值是63.70 μg/mL,平均抗性水平为30.48倍,最高抗性水平达142.97倍。其中江苏、山东、四川三地的菌株抗药性水平明显高于河北、北京、山西和新疆。同时测得病菌群体对苯氧菌酯的敏感基线EC₅₀值为85.82μg/mL,且白粉病菌对甲氧基丙烯酸酯类杀菌剂苯氧菌酯和三唑类杀菌剂三唑酮之间无交互抗性。该结果可为这两类杀菌剂在生产上的合理应用和抗药性治理提供依据。

Monitoring of Blumeria graminis f. sp. tritici isolates to triadimefon in 2002 and establishment of pathogen base-line sensitivity to kresoxim-methyl

109 isolates of wheat powdery mildew (Blumeria graminis f. sp. tritici) were collected from Beijing, Jiangsu, Shandong, Shanxi, Hebei, Sichuan and Xinjiang of China in 2002. The sensitivity of these isolates to triadimefon and kresoxim-methyl was tested by seed treatment and detached leaf segment method. The results showed that the average EC₅₀ of triadimefon was 63.70 μg/mL, the mean resistant factor was 30.48. The resistance of wheat powdery mildew from Jiangsu, Shandong and Sichuan to triadimefon was higher than that from Hebei, Beijing, Shanxi and Xinjiang. The base-line sensitivity of wheat powdery mildew to kresoxim-methyl was 85.82 μg/mL, and there was no cross-resistance between triadimefon and kresoxim-methyl in B. graminis f. sp. tritici. The results will provide a reference for management of the resistance of these two kinds of fungicides to wheat powdery mildew, as well as their rational application in disease con-troll.