September 28, 2007

Figure 1. Locations where soybean rust has been scouted (green) and identified (red). (Map courtesty the national USDA Soybean Rust Web site.)

On Friday, September 21 soybean rust was found for the first time in Kansas. The reported find was in a sentinel plot in Montgomery County which is on the southern border of Kansas, close to some finds in northern Oklahoma. This was one of 20 sentinel sites established in Kansas as part of the national soybean rust monitoring efforts. Funding for the sentinel monitoring program is provided by the Soybean Checkoff program and USDA. Current sites where soybean rust has been confirmed are shown in Figure 1.

At this time late-planted, double-cropped soybeans of which there are 300,000 to 400,000 acres are the only fields which might be affected. The yield potential on these acres is usually low enough that a fungicide application would be questionable. Growers of double crop soybeans in Nebraska are encouraged to stay tuned for what develops in Kansas. While it may not affect them this year, it could be a good lesson on how to handle the situation, should it develop next year.

We are monitoring 30 sentinel plots in Nebraska. No soybean rust has been found in Nebraska yet. To keep up with further soybean rust developments and to track movement, please check the national USDA Soybean Rust Web site at sbrusa.net. There is also a link to this site at the UNL Soybean Rust Web site at soybeanrust.unl.edu.

Loren J. Giesler
Extension Plant Pathologist