A network that helps people worldwide obtain rapid advice and information on crop protection, including the identification and management of plant pests.
PestNet is a network that helps people worldwide obtain rapid advice and information on crop protection, including the identification and management of plant pests. It started in 1999. Anyone with an interest in plant protection is welcome to join. PestNet is free and is moderated, ensuring that messages are confined to plant protection.
March 2006. A request to identify leaf spots of Plumeria from Puket, Thailand and information on how to get rid of them.
From teh photos it appeared to be Plumeria (Frangipani) rust, Coleosporium plumeriae.It should be possible to find the orange spores, especially on leaves that have been recently infected. And, if it is rust, expect to see some defoliationdue to this disease.
It is possible to have mixtured infections of the rust and also anthracnose (Colletotrichum gloeosporioides). The lesions do not look very rust-like, rather they look to have the symptoms expected from anthracnose infection. However, there are sure to be rust pustules in the lesions as well. there are some useful references to the rust disease on the Internet: