湖北省小麦赤霉病菌对多菌灵、戊唑醇和咪鲜胺的敏感性

对2014年采自中国湖北省7个县、市的206株小麦赤霉病菌样品进行单孢分离与鉴定，并采用菌丝生长速率法随机测定了其中100株菌株对多菌灵、戊唑醇和咪鲜胺的敏感性，建立了其敏感基线。结果表明:多菌灵、戊唑醇和咪鲜胺对湖北省小麦赤霉病菌的EC50值范围分别为0.115~0.705、0.006~1.356和0.002~0.370 μg/mL，平均值分别为0.248、0.181和0.040 μg/mL；供试100株小麦赤霉病菌对3种药剂的敏感性频率均呈单峰拟正态分布，因此可将所得各EC50平均值分别作为湖北省小麦赤霉病菌对3种药剂的敏感基线参考值。以各药剂EC50平均值的10倍作为敏感性鉴别浓度，对2015及2016年湖北省小麦赤霉病菌的敏感性进行了监测，在该鉴别浓度下，多菌灵、戊唑醇和咪鲜胺对2015年小麦赤霉病菌的平均抑制率分别为100%、85.14%和82.35%，对2016年小麦赤霉病菌的平均抑制率分别为100%、76.67%和73.62%。研究表明，虽然戊唑醇和咪鲜胺对2016年小麦赤霉病菌的抑制率略有下降，但整体而言，湖北省小麦赤霉病菌对多菌灵、戊唑醇及咪鲜胺仍具有较高的敏感性。

Sensitivity of Fusarium graminearum from Hubei province to carbendazim, tebuconazole and prochloraz

In 2014, 206 single-spore isolates ofFusarium graminearum collected from seven districts in Hubei province were identified by morphology. Sensitivity of 100 randomly selected isolates to carbendazim, tebuconazole and prochloraz was assayed by using mycelium growth inhibition method, and the sensitivity baseline was established. The results showed that the EC50 values of carbendazim, tebuconazole and prochloraz toF. graminearum isolates were in the ranges of 0.115-0.705, 0.006-1.356 and 0.002-0.370 μg/mL, and mean values of 0.248, 0.181 and 0.040 μg/mL, respectively. The sensitivity distributions of the 100 isolates to these three fungicides all followed unimodal quasi-normal distribution , which indicated that the EC50 mean values could be used as the sensitivity baseline ofF. graminearum in Hubei province to these three fungicides. Using 10 times of the mean EC50 value of each fungicide as the discriminatory dose, the sensitivity ofF. graminearum in Hubei province was monitored from 2015–2016. The study showed that the average inhibition rates of carbendazim, tebuconazole and prochloraz toF. graminearum isolates were 100%, 85.14%, 82.35%, respectively, in 2015, and 100%, 76.67%, 73.62%, respectively, in 2016. In summary,F. graminearum isolates in Hubei province still wxhibit high sensitivity to carbendazim, tebuconazole and prochloraz, although the inhibition rates of tebuconazole and prochloraz were slightly decreased in 2016.