Posted on Sep 20, 2016 by Suzanne Bissonnette
Soybean rust (Phakopsora pachyrhizi) has been found in southern Illinois. Samples were collected in Williamson county on 9/11/16 to make observations for other fungal foliar leaf disease. Soybean rust was found sporulating in pustules on the bottom surface of the leaves. The field was at R6 so yield loss to that field is unlikely. While this very late in the season, there are still many fields in southern Illinois that are green and producers should consider scouting for soybean rust.
The IPM PIPE website shows soybean rust observations in North America (http://sbr.ipmpipe.org). Soybean rust sentinel plots and monitoring programs are no longer active in Illinois. Any soybean leaves that are suspicious for soybean rust however, can be sent to the University of Illinois Plant Clinic (http://web.extension.illinois.edu/plantclinic/) for diagnosis. Further information on soybean rust can be found from this 2013 article http://bulletin.ipm.illinois.edu/?p=1501