Entomology and Plant Pathology, Oklahoma State University
127 Noble Research Center, Stillwater, OK74078
Vol. 12, No. 5
Feb 27, 2013
Wheat Disease Update
Bob Hunger, Extension Wheat Pathologist
Although still no confirmed reports of foliar disease in Oklahoma wheat, the recent moisture will facilitate foliar disease development as temperature raises as we enter March. Symptoms of wheat soilborne mosaic/wheat spindle streak mosaic are evident in that disease nursery here at Stillwater, and with the wet/cold weather of this and last week should become more prominent as we get into March.
Below are reports from several other states that I have received recently in which you may have an interest. I would call your attention to the sentences in the report from Dr. Harrison (Louisiana) that I have underlined as these describe the appearance of stripe rust on seedling wheat, which typically does not produce the characteristic striping associated with stripe rust on adult plants.
Texas Dr. Amir Ibrahim (Prof, Small Grains Breeding and Genetics, Texas A&M University) 23-24 Feb-2013: The following are leaf and stripe rusts conditions at Uvalde, Castroville, and College Station in South Texas:
Uvalde (2/23/2013): The wheat crop is at Feekes 4-5. Leaf rust continues to develop uniformly at this location and is severe on susceptible cultivars such as ‘TAM 110’. Strip rust continues to develop but might be slowed by increasing temperatures at this location. It seems we have the same race that was virulent on ‘Everest’ and ‘TAM 111’ last year. I could not detect stripe rust on lines that have Yr17. I noticed the severest reaction on ‘Garrison’ as expected based on last year’s reaction. ‘TAM 111’ and ‘Armour’ were rated 10S each, and Everest was rated 5S.
Castroville (2/23/2013): The rust evaluation nursery looks very pretty and lush. Leaf rust continues to develop uniformly at this location. Powdery mildew is heavy in the lower and