Stem Rust of Wheat: An Oklahoma Perspective B. Hunger, B. Tipton, J. Edwards, A. Klatt, and B. Carver Oklahoma State University

Wheat Leaf Rust (Puccinia triticina)

Wheat Stripe Rust (Puccinia striiformis f. sp. tritici) Apache, OK; Mar, 2005Lahoma, OK; Apr, 2005

Wheat Stem Rust ( Wheat Stem Rust (Puccinia graminis f. sp. tritici) Photo above courtesy of Cereal Disease Lab, St. Paul, MN Lahoma; mid 1980s

Wheat Rust Losses: Oklahoma Data from Cereal Disease Lab, St. Paul, MN

StateNo. of years since 1918 Avg. loss (%) Greatest loss & year TX % in 1922, 1935 OK % in 1918 KS % in 1935 NE % in 1962 SD % in 1953 ND % in 1935 Wheat Yield Losses Reported for Stem Rust Since 1918 in the Great Plains (Source: Cereal Disease Lab, St. Paul, MN) Only minimal losses since the mid-1960s

1935: Percent Loss to Wheat Stem Rust Data and slide courtesy of Cereal Disease Lab, St. Paul, MN

M. Lee Phillips, 1940 Canadian Cty. Ag Extension Report, p. 17

Mr. Joseph Danne

M. Lee Phillips, 1939 Canadian Cty. Ag Extension Report, p. 21

Pedigree for Triumph Hard Red Winter Wheat Kanred/Blackhull//Burbank’s Quality/3/Kanred/Blackhull Kanred: a selection from Crimean (a ‘Turkey’ type) released from KSU in Blackhull: a selection from Turkey made by E.G. Clark (KS farmer-breeder) also released in Burbank’s Quality (CItr 6607): a white spring wheat; “grown experimentally and to a small extent commercially in CA, MT, and OK in 1920.” Danne’s first crosses with Burbank’s Quality were made in 1925.

Triumph Hard Red Winter Wheat Released in 1940 by Joseph Danne; grown in TX, OK, KS, CO, MO, IL, and KY. Superior characteristics included early maturity, short & stiff straw, resistance to loose smut & stem rust, et al. Acreage reached: 1944 – 72, – 3,364, – 5,596, – 2,223, – 6,341, – 2,298,643

Triumph 64 Hard Red Winter Wheat Originally released by Mr. Danne in 1948 or 1949 as ‘Rust Resistant Triumph’; in 1964, was re-released by the OAES as ‘Triumph 64’. Tmp 64 is very similar to Triumph except for the rust resistance (which had been adapted to by PRT). Tmp 64 heads 10 to 11 days earlier than Turkey or Kharkof, which head about 2 weeks later and mature about 1 week later than wheats grown in Oklahoma today (Dr. Brett Carver, OSU Wheat Breeder).

Comparison of Heading and Cutting Dates Earliest (1940): heads – May 7 th cut – June 19 th Latest (1940): heads – May 17 th cut – June 29 th March 28 th – wheat is approaching boot stage, and we will see heads by mid-April.” “Our earliest maturing varieties are quite likely a month earlier than those varieties popular back in the day of Joseph Danne.” “I don’t remember a year in the 18 I have been in Canadian County that at least some wheat wasn’t cut before Memorial Day – harvest in most years has a solid start by the last week of May.” – Brad Tipton – Extension Educator, Canadian County

Burleigh, Schulze, and Eversmeyer Some aspects of the summer & winter ecology of wheat rust fungi. Plant Dis. Rep. 53: Conclusions: PGT persist through the summer and fall months but no inoculum in any form detected after January of any year. PRT present continuously in the area studied. Figure 1. Darkened area indicates where samples were taken during the 4-year study.

Chester, Ray, McLaughlin, and Hoffmaster Diseases of field crops in Oklahoma. OAES Circular C-119, 23 pp.

Chester, K. S The Nature and Prevention of Plant Diseases. The Blakiston Company, Philadelphia, 584 pp. ► PGT lives through the winter on wheat & produces uredospores in southern TX & Old Mexico; spring infections result from uredospores from the winter infections; teliospores are functionless. ► Stem rust in northern TX, OK, and southern KS is caused by uredospores blown in by south winds from southern TX and Old Mexico; teliospores are functionless. ► From northern KS to Canada, aeciospores from barberry and uredospores blown up from the south serve as inoculum; also teliospores may overwinter and lead to stem rust. ► In the southern Great Plains, varieties such as Early Blackhull escape stem rust because of their earliness.

Summary/Conclusions ► Historically, stem rust is more severe in TX and states north of Oklahoma. ► This is occurs for two reasons: 1.The early maturity of varieties grown in OK. 2.The inability of PGT to overwinter in OK. ► Because of these factors, stem rust in OK results from uredospores blown up from TX, which arrive too late in the spring to cause significant damage. ► Could this change?? Historically stripe rust has not been a problem in OK because of these same reasons. However, in three of the last six years, this has not been the case.

Popham, W.L. ???? Stem rust and the common barberry. USDA, Bureau of Entomology and Plant Quarantine, Division of Plant Disease Control.

Popham, W.L. ???? Stem rust and the common barberry. USDA, Bureau of Entomology and Plant Quarantine, Division of Plant Disease Control.