Skip to main content

Content by Emmanuel Byamukama

Green soybean plant with white mold present on the stem and pod.

Start of Flowering Is the Ideal Time for White Mold Management in Soybeans

Some early planted soybeans are starting to flower (R1 growth stage). One soybean disease that needs to be managed at this growth stage is white mold.

Map of South Dakota showing Fusarium head blight risk. Green indicates low risk, yellow moderate risk, and red high risk. Most of the state is green except for scattered, yellow areas within Edmunds, Faulk, Hyde, Hand, Buffalo, Jerauld, Brule, Aurora, Turner, Lincoln, McCook, Lake, Brookings, and Kingsbury counties. Some red, high risk areas are in Buffalo, Brule, Hyde, and Minnehaha counties.

Fusarium Head Blight Predicted Risk for Spring Wheat

Most of the spring wheat is at or will soon be at flowering. One disease that can develop in wheat at this growth stage is fusarium head blight (FHB or scab).

Yellow and brown streaks on a winter wheat leaf indicative of bacterial leaf streak symptoms.

Bacterial Leaf Streak Developing at Low Level in Winter Wheat

A few winter wheat fields were found with bacterial leaf streak starting to develop at low levels. Bacterial leaf streak is usually observed starting from flag leaf growth stage. It can be severe on the upper leaves when there is prolonged leaf wetness resulting from frequent rains.

Green winter wheat leaf with yellow-orange strips indicative of stripe rust.

Stripe Rust Found in Winter Wheat at Low Severity

Stripe rust was observed in the crop performance trials at the Dakota Lakes Research Farm in Hughes County and at Ideal in Tripp County. At both locations, stripe rust was at a low severity.

Yellow and green leaf of oats. Yellowing color is a symptom of Barley yellow dwarf virus.

Barley Yellow Dwarf Developing in Oats

A few oat fields that were recently scouted were found to have barley yellow dwarf virus infected plants. The infected plants were few and scattered throughout the oat fields.

Map showing the risk of Fusarium head blight with green equaling no risk, yellow equaling moderate risk, and red equaling high risk. Much of the eastern half of South Dakota is red.

The Fusarium Head Blight Prediction Tool Indicates High Risk

Winter wheat is starting to flower. It is important to monitor weather conditions from when wheat is heading until flowering to decide the need for fungicide application to manage Fusarium head blight.

Three wheat plants exhibiting disease symptoms. From left: Tan spot, powdery mildew, and Barley yellow dwarf.

Winter Wheat Diseases Update: Fungal Diseases and Barley Yellow Dwarf Developing

Tan spot and powdery mildew as well as barley yellow dwarf were found developing at low levels in winter wheat fields scouted the week of May 24, 2020.

A soybean root with several small white cysts growing on it.

Soybean Cyst Nematode in South Dakota: History, Biology, and Management

Factsheet about Soybean Cyst Nematode history, biology and management in South Dakota

Wheat plants exhibiting symptoms of tan spot and powdery mildew.

Does Early Fungicide at Tillering Result in a Profitable Yield?

Tan spot and powdery mildew pathogens are two residue-borne pathogens that can infect wheat early in the season. These diseases can lead to poor tillering, and their continued development can lead to yield loss.

wheat field

2019 Wheat Field Plot Trials Summary: Fungal and Bacterial Disease Trials

This publication provides a summary of wheat trials conducted in 2019 to determine efficacy of various products in managing wheat diseases.