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Soybean Diseases

All Soybean Diseases Content

Alfalfa shoots with top leaves showing yellow patches interspersed with green patches, symptoms for Alfalfa mosaic virus

Alfalfa Mosaic Developing in a Few Alfalfa Fields

In South Dakota, alfalfa fields that were recently scouted were found to be infected with Alfalfa mosaic virus (AMV) at a very low incidence. AMV is a common virus in alfalfa that can also infect soybeans.

An empty grain bin full-air floor is plugged by insect webbing.

Stored Grain Pests: Spring Insect and Disease Issues

Grain storage is a key component in getting your crop to market. Aside from watching bins for spoilage, moisture, and temperature changes, make sure you are looking for signs of pest infestation.

Soybean seed drill. Courtesy: United Soybean Board

Fungicide Seed Treatment Considerations for 2019

With the excessive soil moisture and flooding that has occurred throughout South Dakota, growers may be thinking about using a fungicide seed treatment this planting season.

soybean pods

2018 Field Plot Summaries for Soybeans: Plant Disease and Fungicide Trials

This is a summary of soybean field research studies that were conducted in 2018. The purpose of these studies was to assess efficacies of fungicides for foliar disease management and nematicides/seed treatment products for nematode management. The studies were conducted on growers’ land in Brookings and Volga Research Farm.

Diseases & Disorders teaser

Fungicide Resistance: Risk and Management

What is fungicide resistance?
Fungicide resistance can be defined as when a pathogen population is no longer sensitive or has reduced sensitivity to the fungicide that used to control the same pathogen.

A patch of soybeans with several plants exhibiting browning and yellowing leaves.

Plant Disease Management Decisions to Make Before Planting

For most plant diseases, in-season management choices are very limited. In fact, there are no in-season management options available for diseases caused by nematodes, viruses, and bacteria.

green leafy plants

Soybean Vein Necrosis Virus Detected in South Dakota Soybeans

A new soybean virus called Soybean vein necrosis virus (SVNV) was detected in South Dakota soybean fields in Davison and Union counties. Symptomatic plants were sporadic and found along the field borders. Infected plants showed mild to moderate severity.

A soybean field with a large brown area due to a lightning strike.

Seeing Dead Soybean Plants in a Circular Pattern? Could Be Due to Lightning

While quite uncommon for lightning to damage row crops, it does happen. Thunderstorms can have lightning that can burn soybeans plants leading to their death.

green soybeans with white mold

White Mold Development: Is your soybean field at risk?

According to USDA-NASS crop progress report for the week of July 17, 49% of the soybeans in South Dakota are at flowering. The flowering growth stage is also the time when white mold infection is initiated. The white mold pathogen infects the soybeans through the flowers that are senescing after pollination.

A young man driving a soil sampling tool into a soybean field

Consider SCN Sampling This Spring 

Soybean cyst nematode management starts with a soil test to determine the presence or absence of this nematode in the soil.