Canna rust (193)

Pacific Pests, Pathogens and Weeds - Online edition

Pacific Pests, Pathogens & Weeds

Canna rust (193)

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Photo 1. Canna with rust, Puccinia thaliae.

Photo 2. Spots of canna rust, Puccinia thaliae, beginning to discharge spores on underside of the leaf.

Photo 3. Close-up of the powdery masses of Puccinia thaliae spores, released from pustules on the lower surface of the leaf.

Summary

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.

Common Name

Canna rust

Scientific Name

Puccinia thaliae (previously known as Puccinia cannae).

Photo 4. Dark brown structures developing which contain the teliospores of Puccinia thaliae.

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.

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