Sensitivity of Cercospora chrysanthemi to Benomyl and QoI fungicides in Osaka Prefecture, Japan

Abstract

Thirty isolates of Cercospora chrysanthemi were collected from garland chrysanthemum fields in Osaka Prefecture and their sensitivity to benomyl and azoxystrobin (QoI) was evaluated. For benomyl, 83% and 8% of the isolates collected in 2016–2017 and 2021–2023, respectively, were resistant. For azoxystrobin, 100% and 50% of the isolates collected in 2016–2017 and 2021–2023, respectively, were resistant. The QoI sensitivity may have been influenced by its application to another disease.