Plumeria rust caused by Coleosporium plumeriae on frangipani trees in Sumatra, Indonesia

Powdery rust pustules of bright yellow-orange color were observed forming on both mature and young leaves of red frangipani (Plumeria rubra) in the province of Riau, Sumatra, Indonesia. Based on morphological characteristics and DNA sequence of the internal transcribed spacer region (ITS), the rust fungus was identified as Coleosporium plumeriae, only urediniospores were found on the infected leave. Inoculation trials confirmed the pathogenicity of C. plumeria, fulfilling the Koch’s postulates. This is the first report and characterization of plumeria rust caused by C. plumeria on frangipani on the island of Sumatra, Indonesia.