In April 2008, cherry (Prunus yedoensis Matsumura) in Jeju exhibited severe disease of branches forming
numerous twigs. Five isolates from diseased leaves were identified as Taphrina wiesneri on the basis of biological
and genetic characteristics. Twenty one commercial fungicides were tested for control of the disease in
vitro. Of the 21 fungicides, triazole compounds (difenoconazole, propiconazole and tebuconazole) showed relatively
good antimicrobial activities. Results from the planta bioassays indicated that triazole compounds
reduced the witches' broom disease showing control value 25.7~52.8% compared with the nontreated controls.