Diseases & Disorders

All Diseases & Disorders Content

A soybean field with plants yellowing and dropping leaves in larger portion of the field while the rest of the field has green soybean plants.

Drought Stress or Stem Canker Killing Soybean Plants?

Several soybean fields scouted in a number of Eastern counties have plants dying or dropping leaves prematurely. While the majority of these fields have drought stress causing early senescence, a few fields have also stem canker developing

: Golden colored wheat field with much taller, golden colored, volunteer rye within.

Volunteer Winter Rye Could Be a Source of Ergot in Your Wheat

A few wheat fields scouted this summer were found with volunteer rye infested with ergot. Volunteer rye, in addition to being a weed, can be a source of ergot, which is a concern for winter wheat producers.

soybean field with white mold

White Mold (Sclerotinia Stem Rot) of Soybean

Fact sheet of the symptoms and signs for while mold in soybean.

Soybean plant with with yellow-chlorotic blotches between leaf veins and noticable browning due to sudden death syndrome.

Sudden Death Syndrome of Soybean

Fact sheet discussing sudden death syndrome of soybean.

Small white cylindrical mites on a wheat leaf.

Wheat Streak Mosaic Virus is Prevented Before Planting Winter Wheat

Wheat streak mosaic disease (WSMD) is one of the important diseases in winter wheat and can lead to severe yield losses.

Diseases on three different wheat plants. From the left: powdery mildew, fusarium head blight, and leaf rust.

Winter Wheat Diseases Update

Powdery mildew, fusarium head blight and leaf rust were observed in a few winter wheat fields recently scouted. The recent rainfall showers and warm temperatures have favored these diseases to develop in winter wheat.

Green corn plant with abnormal tassel growth.

Crazy Top Disease Developing in Corn

Crazy top disease was observed in a few fields in the Southeast counties in the state. This disease develops in corn that is flooded or under full water saturation when corn has not reached the four-to-five leaf stage.

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.