Utah State University Extension
Stripe rust, or yellow rust, is primarily a foliar fungal disease of wheat, although it can infect spike and stem tissues. If the pathogen infects the spike (head) it causes extensive quality and grain yield loss. The disease is caused by the fungus Puccinia striiformis f. sp. tritici. The fungus can only survive and reproduce on wheat. It survives from one season to the next on volunteer plants.
Pace, Mike; Israelsen, Clark; Evans, Kent; and Barnhill, James, "Wheat Stripe Rust" (2008). All Current Publications. Paper 989.