Entomology and Plant Pathology, Oklahoma State University
127 Noble Research Center, Stillwater, OK74078
Vol. 11, No. 16
Apr 2, 2012
Wheat Disease Update
Bob Hunger, Extension Wheat Pathologist
Wheat continued rapid development across Oklahoma this past week with yield potentials still looking outstanding. Yesterday I sprayed my foliar fungicide trial (Jagger), which ranged from boot (GS 10) to heads nearly fully emerged (GS 10.5). Overall I would place that trial at GS 10.2 (heads about ¼ emerged). This is 2-3 weeks earlier than I typically make this application. It strikes me from calls over this past week, that this is representative of where wheat is at across much of Oklahoma.
Stripe rust continues to be reported from across southwestern, central, and west central Oklahoma, but not as many reports from the north central and northwestern parts of the state. However, these reports indicate only scattered/light infections. With daytime temperatures into the 90s over the weekend (and 80s last week) and night temperatures in the 60s, stripe rust should be “shutting down.” It could be revived with strikingly cool temperatures and moisture, but I don’t see it being a major factor in most parts of Oklahoma this year.