Daylily Rust Information Page

Daylily Rust Information Page

Daylily rust on daylily.
Image by Susan Bergeron

Daylily rust on Patrinia villosa
in Japan. Image by Dr. Y. Ono

Introduction

Daylily rust is caused by the fungus Puccinia hemerocallidis. It is not a new disease of daylilies, having been reported previously from China, Taiwan, Korea, Japan and Russia (Sakhalin, Kuriles and Siberia). There is a record of daylily rust specimens having been collected in Siberia, Russia, as long ago as 1878. Unfortunately, the disease is now also in North America, having first been identified in the south-eastern United States in August 2000. While it was initially spread to many other areas on shipped plants, the main method of rust spread in nature is by wind blown spores.

Daylily rust so far appears to have successfully overwintered in the warmer areas of the United States to USDA Zone 7. It apparently does not persist in all infected Zone 7 gardens however, therefore it is hoped that rust will not be a significant problem in colder zones unless, perhaps, it can utilize the alternate host, Patrinia, as it does in Asia (while there are many different plant rusts affecting many different plants, only Hemerocallis and Patrinia are susceptible to daylily rust). It is conceivable that daylily rust could persist in some colder areas than one would otherwise expect where there is a protective covering of deep and continuous snow throughout the winter, or perhaps under a heavy winter mulch, or in close proximity to a warm house wall. Of course, it may also persist in greenhouses.

On this site you will find images of daylily rust on daylily and Patrinia; information from its native Asia, animations, diagrams, and explanations of the rather complicated life cycle; a list of daylily and patrinia species reported to be susceptible; images of rust and non-rust problems; a suggestion for reducing the risk of bringing the disease into your garden; a page of relevant scientific research articles, some with links; links to other sites on daylily rust, breeding for disease resistance, fungicide information and a link to a survey. Please input your daylily rust observations into the survey. The more people do this the more useful the results on cultivar susceptibility will become. You can access the survey results (for cultivars that have had sufficient input) on the survey page.

Daylily Rust in its Native Regions

Daylily Rust Biology

Images of Daylily Rust

Images of Non-Rust Leaf Problems

Reducing the Risk

Suggested way to reduce the risk of introducing daylily rust

Daylily Rust Research

List of research articles, presentations etc. that discuss daylily rust

Daylily Rust Survey

Daylily Rust Survey (External link)

Links to Other Relevant Web Sites

Links Page

Photo credits: All rust images on this page except where otherwise specified are by Jay Laundre except for the "Tissue Test" and Daylily Leaf with Rust - Image 6 which are by Jennifer Jackson, and Early Daylily Rust and Early Daylily Rust - Check Undersides of Leaves which are by Jennifer Llewellyn. All non-rust images (except for Not Rust Image 3 by Jay Laundre, and the first image of leaf streak) are by Susan Bergeron except where specified otherwise. Animations by Susan Bergeron

� Susan Bergeron, this page last updated 5th December 2009. Please report any problems with this page to:
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