Stripe Rust Report May 5th 2013

Stripe rust has been reported in Northern Idaho by Doug Finkelnburg in the soft white winter variety 'Brundage' on the University of Idaho's research farm in Moscow, ID. Stripe rust is also confirmed in southern Idaho from the Twin Falls / Filer areas (also in Brundage) and in Declo (also in Brundage). If you are growing a susceptible variety, please scout and spray with fungicides as needed. While visiting fields in the Twin Falls area, many fields (approximately 30%) of winter wheat and winter barley were infected with BYDV. Most of the fields of winter wheat were Stephens. What appeared to be a resistant reaction to stripe rust was visible on many of the flag leaves of Stephens. Please don't assume resistance with be maintained in varieties reported as resistant, as changes can and do occur in the race structure of the stripe rust fungi. Please check our website for additional information, pictures, and fungicide efficacy chart.  

Additional reports of stripe rust in wheat are coming in from Aberdeen, American Falls and the Pocatello area. Chad Jackson (University of Idaho) reported stripe rust in Brundage in the border of research plots on the Research station. Brad Clayson and Ron Ellis report stripe rust on the Fort Hall reservation and near Pocatello and American Falls. Additional reports continue from the Magic Valley. Most reports are of stripe rust in Brundage. If you find stripe rust in other varieties, please let me know. Again, further information is available on our website.

 

We are having reports of WSMV in winter wheat from the northern Utah / very southern Idaho area in winter wheat. I had a beautiful sample last week. Reports of brown wheat mite in spring barley in the Soda Springs area gives concern with the possible vectoring of Barley yellow streak mosaic virus, but I have not yet seen viral symptoms in barley. 

Please refer to this publication put out by Montana State University on Brown wheat mite:

http://msuextension.org/publications/AgandNaturalResources/MT200212AG.pdf

Also, this information from  Kansas State:

http://entomology.k-state.edu/extension/insect-information/crop-pests/wheat/brown-wheat-mite.html 

and these references to wheat curl mite (vector of WSMV):

http://www.ca.uky.edu/entomology/entfacts/ef117.asp

http://www.ext.colostate.edu/pubs/insect/05578.html

 

 

 

Juliet Marshall, Ph.D.

Associate Professor, Cereals Pathology and Agronomy

Idaho Falls R&E Center
1776 Science Drive Suite 205
Idaho Falls, ID 83402
208-529-8376 office
208-390-4859 cell

http://www.extension.uidaho.edu/scseidaho/