Foliar Fungicides Publication Available

March 18, 2008
ICM News

Daren Mueller, Extension Plant Pathologist

If the risk of soybean rust development is high and the crop is before growth stage R6, fungicides may be needed. For fungicides to be most effective, they need to be applied as close to the time soybean rust initially infects plants in a field.

In most cases, this means that fungicide decisions will have to be made at a time when the risk is high, but before the time when rust is detectable in the field. Detecting low levels of soybean rust (<10 percent) typically requires incubating leaves and observing them under laboratory conditions by a trained diagnostician.

A bulletin titled Using Foliar Fungicides to Manage Soybean Rust was originally published in 2005 and recently was updated and expanded. This book reviews the factors involved in making fungicide spray decisions and basic fungicide information, including mode of action, application and use strategies. An updated list of available products also is posted in Appendix B.

This book was prepared by soybean pathologists working in many regions of North America. This full-color publication contains numerous illustrations, photographs, maps, tables, and charts, as well as a glossary of terms and a list of sources for additional information.

Daren Mueller is an extension specialist in the Department of Plant Pathology.

Links to this article are strongly encouraged, and this article may be republished without further permission if published as written and if credit is given to the author, Integrated Crop Management News, and Iowa State University Extension and Outreach. If this article is to be used in any other manner, permission from the author is required. This article was originally published on March 18, 2008. The information contained within may not be the most current and accurate depending on when it is accessed.


Daren Mueller Professor

Daren Mueller is an associate professor and extension plant pathologist at Iowa State University. He is also the coordinator of the Iowa State Integrated Pest Management (IPM) program. Daren received his bachelor's degree from the University of Wisconsin-Madison in 1996, and his master's degree a...