- Worldwide distribution. On Canna and relatives.
- Yellow to tan powdery spots on leaves and stems, often parallel to veins, becoming dark. Leaves die early. Spores ('urediniospores') spread in wind, but need water to germinate.
- A disease affecting the quality of ornamentals.
- Cultural control: remove infected leaves when spots first appear; do not compost the diseased leaves.
- Chemical control: copper or mancozeb.
Pacific Pests, Pathogens, Weeds & Pesticides
Canna rust (193)
Photo 2. Spots of canna rust, Puccinia thaliae, beginning to discharge spores on underside of the leaf.
Puccinia thaliae (previously known as Puccinia cannae).
AUTHOR Grahame Jackson
Information from (including Photos 1,3&4) McKenzie, E. (2014) Puccinia thaliae: PaDIL - (http://www.padil.gov.au); and from Bhasabutra T, et al. (2011) Canna rust (Puccinia thaliae): PaDIL - http://www.padil.gov.au; Nelson S (2013) Rust of Canna Lily. College of Tropical Agriculture and Human Resources, University of Hawai'i at Manoa. (https://www.ctahr.hawaii.edu/oc/freepubs/pdf/PD-96.pdf). Photo 2 Kohler F, et al. (1997) Diseases of cultivated crops in Pacific Island countries. South Pacific Commission. Pirie Printers Pty Limited, Canberra, Australia.
Produced with support from the Australian Centre for International Agricultural Research under project PC/2010/090: Strengthening integrated crop management research in the Pacific Islands in support of sustainable intensification of high-value crop production, implemented by the University of Queensland and the Secretariat of the Pacific Community.