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Emmanuel Byamukama

Associate Professor & SDSU Extension Plant Pathologist


Plant Science Building 107
Agronomy, Horticulture & Plant Science-Box 2108
University Station
Brookings, SD 57007

Generate research-based information to help growers manage plant diseases effectively and sustainably.
Provide alerts and updates of diseases developing in crops
Help growers diagnose plant diseases affecting their field crops
Provide fungicide safety and resistance management education

Also by Emmanuel Byamukama

Three corn diseases. From left: Southern Rust, Bacterial Leaf Streak, and Eyespot.

Southern Rust, Bacterial Leaf Streak, and Eyespot Are Developing in Corn

Southern rust was found in Yankton County, bacterial leaf streak was found in Brule County, and eyespot was found in several fields and counties the week of July 27, 2020.

Left: Green soybean plants covered with yellow and brown spots indicative of frogeye leaf spot infection.  Right: Green soybean trifoliate that is covered in brown spots.

Deciding on Fungicide Application to Manage Mid-Late Season Soybean Leaf Fungal Diseases

Soybean leaf diseases can develop in some soybean fields to reach yield-reducing levels. The question that growers often ask is whether it is profitable to apply a fungicide to soybeans at the R3/R4 growth stage in South Dakota.

A mostly green corn leaf that is in brown to yellow markings caused by southern rust.

Is a Fungicide Applied at Tasseling Profitable in Corn?

Corn is currently at tasseling/silking across the state. This is usually the growth stage when a fungicide is applied to control fungal diseases.