Diazinon for severe infestations. Improve air circulation. Benomyl or Captan. Round brown or black spots on the upper or under surface of leaves, sometimes on tips. Centre of plant turns black and rotten.
Leaves pull off easily.
Slightly damp brown spots on leaf surface. Mostly affect Phalaenopsis and Paphiopedilum. Remove infected parts and treat with copper-based fungicide. Disinfect all tools. Disinfect all tools.