Dry conditions in the southern United States early this growing season greatly reduced the risk soybean rust will show up in Nebraska this year, says Loren Giesler, a University of Nebraska-Lincoln plant pathologist.
Soybean rust hasn't hit Nebraska in the four seasons it's been in the U.S. "Once we get to early July, if rust has not become more active, our risk for a significant disease problem is very low to no chance," Giesler says.
Recent rains in some southern U.S. states should increase soybean rust activity, but it may simply to be too late for rust to move into Nebraska this year, he adds.
Soybean rust was found June 2 in Liberty County along the gulf in eastern Texas. "That was the earliest we have seen soybean rust this far west, but a significant amount of rust has not been found in Texas and they are currently pretty dry," Gielser says. "This is definitely a potential source of rust for Nebraska, but there will need to be much more development and spread for this to reach us."
Although it's still unknown whether rust will strike Nebraska, several resources are available to soybean growers to keep track of its movement and to gain more information about the disease and its management.
The UNL Targeting Soybean Rust Web site is available at soybeanrust.unl.edu, a site that offers a one-stop soybean rust resource center for Nebraska soybean growers.
"Staying aware of where soybean rust is throughout the growing season is critical to managing the disease," says Giesler. "This Web site offers a link to the latest confirmed occurrences as posted on the U.S. Department of Agriculture's Soybean Rust Information Web site. It also will offer up-to-date soybean rust fungicide information."
The Web site offers photos of soybeans infected with rust and other diseases, crop insurance information and other recommended Web sites.
Again, sentinel plots have been planted across the U.S., including 30 in Nebraska. Many of these plots are being coordinated by UNL Extension educators.
All sentinel plot observations are entered into the USDA Soybean Rust Web site at www.sbrusa.net.
Other resources available throughout the growing season include:
- The soybean rust phone hotline at (877) NEB-RUST. This recorded message offers updates on where soybean rust has spread, risk level for Nebraska and management recommendations throughout the growing season. It is funded by the Nebraska Soybean Board and is operated by UNL Extension.
- Crop Watch, UNL Extension's crop production newsletter, at cropwatch.unl.edu/.
- Nebraska Extension NebGuides NF633, Soybean Rust: How Great is the Threat for Nebraska?, NF634, Fungicides to Manage Soybean Rust: What are the Product Differences?, and NF652, Soybean Rust Fungicide Use Guidelines for Nebraska. All are available online at http://www.ianrpubs.unl.edu/epublic/pages/publicationD.jsp?publicationId=333, http://www.ianrpubs.unl.edu/epublic/pages/publicationD.jsp?publicationId=335 and http://www.ianrpubs.unl.edu/epublic/live/nf652/build/nf652.pdf.
- A national land-grant university soybean rust publication developed by soybean rust specialists across the United States, Using Foliar Fungicides to Manage Soybean Rust (SR-2005), is available at http://www.oardc.ohio-state.edu/SoyRust/index.htm or from local UNL Extension offices for $2.