Rust fungus, Puccinia monoica, on plants in the Truckee District on Mar. 17, 2015. Photo: Joanna Rutkowski.

Rust fungus (Puccinia monoica) on plants located close to the Truckee River near Squaw Valley, CA. Mar. 17, 2015. Photo: Joanna Rutkowski.

Rust Fungus
Puccinia monoica
  • Looks like a bright yellow flower.
  • “Blooms” in the early spring.
  • Usually infects plants of the Arabus genus of the Brassicaceae (Mustard Family).

Record Observations
Species Description:

Puccinia monoica is a type of rust fungus that usually infects plants of the Arabis genus of the Mustard Family (Brassicaceae).  Plants become infected with spores of the rust fungus during the late summer.  During the following spring, the infected plants sprout flower-like clusters of bright yellow leaves, which look completely different from the host plant’s normal flowers and are coated in a sticky, sweet-smelling substance (Roy 1993).  This is an example of floral mimicry: Fungi masquerading as flowers.

In spring, as insects go from flower to flower looking for pollen, they may instead be lured in by the bright colors and fragrant odors of a rust fungus. Frequent visitors to rust fungus include bees, butterflies and flies. The rust fungus uses these insects to transport its spermatia (reproductive cells) from plant to plant (Roy 1993) — a fascinating (and slightly creepy) reproductive strategy.

Additional Images:
Puccinia monoica growing on plants along the Truckee River on Mar. 17, 2015. Photo: Joanna Rutkowski.

Puccinia monoica growing on plants along the Truckee River on Mar. 17, 2015. Photo: Joanna Rutkowski.


A close-up of the Puccinia monoica spores on Mar. 17, 2015. Photo: Joanna Rutkowski.

A close-up of the Puccinia monoica spores on Mar. 17, 2015. Photo: Joanna Rutkowski.

Photos & Information needed!

Do you have information on Rust fungus, or original photographs taken locally?  If so, please contribute photos and observations here, or email information to kelseymccutcheon@gmail.com. Thanks!

 

References:

Roy, B. 1993. Floral mimicry by a plant pathogen. Nature. Vol 362. P.56-58.

Wikipedia: Puccinia monoica http://en.wikipedia.org/wiki/Puccinia_monoica

Characteristics

Share this Project

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.