Submitted to: Barley Newsletter
Publication Type: Other
Publication Acceptance Date: March 31, 1997
Publication Date: N/A
Technical Abstract: Barley stem rust infection was light in the northern plains in 1996, probably because of the decrease in prevalence of stem rust race Pgt-QCCJ, which can overcome the resistance of commercial barley varieties but not most wheat varieties. The reduced frequency of Pgt-QCCJ and the increased frequency of race Pgt-TPMK, which cannot attack most barley varieties, are attributed to reduced acreage of winter wheat varieties susceptible to Pgt-QCCJ in the central plains. Yield losses in barley to both stem rust and leaf rust were minimal in 1996, totaling only 0.02% for stem rust and 0.07% for leaf rust nationally. Three million bushels were lost to barley stripe rust in 1996, which greatly exceeded the combined losses to stem rust and leaf rust. Barley stripe rust was especially severe in California, causing 15% yield losses. An emergency label for Folicur to control stripe rust on barley in the Pacific Northwest helped to hold down losses in Oregon and Washington to just 1% and 2%, respectively. Crown rust, a new disease on barley, was severe in isolated sites in the Dakotas, but did minimal damage overall. Barley crown rust still appears to be restricted to sites relatively close to buckthorn bushes, its alternate host.