This soybean rust update is provided to you by the Michigan State University Field Crop CAT Alert Team.

Asian Soybean Rust Sentinel Plot Scouting Report: July 28 to August 3
Thirteen reports were filed from the 20 sentinel plots during the reporting week.

No soybean rust has been found on soybeans or other plants in Michigan or anywhere in the region, including Ontario, Canada.

Following is a compilation of the scouting reports.

• Growth stage: Ranged between R3 and R5.
• Plant height: Ranged between 20 and 44 inches.
• Degree of canopy closure: Ranged between 95 and 100%.
• Soybean diseases present: Diseases (brown spot, bacterial blight and Phytophthora stem canker) remain at low levels and were only reported in 6 plots. There was one report of moderate downy mildew infection.
• Insects present: Soybean aphids were reported in 10 plots. Five plots have very low levels and five plots ranged from 218 to 280 aphids per plant. One plot had been sprayed for soybean aphids. Other insects present and causing minor foliar damage included Japanese beetles, lady beetles, spider mites and bean leaf beetle.

Three soybean samples from the sentinel plots were submitted to MSU Diagnostic Services to be assayed for soybean rust during the week. These samples all tested negative for soybean rust, testing was done with real time PCR.

MSU Diagnostic Services reports the following pests and problems found on field crop samples submitted in the last two weeks:
Corn: Nitrogen deficiency, Glyphosate injury
Soybean: Downy mildew, Stem canker (Diaporthe), Phytophthora rot, Brown spot (Septoria), Soybean cyst nematode, Potassium deficiency, Dicamba injury
Sugar beets: Cercospora leaf spot, Sugar beet cyst nematode

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