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Soybean Diseases

All Soybean Diseases Content

aerial view of South Dakota farm and surrounding land

Crops

During the growing season, SDSU Extension provides weekly production recommendations.

soybean pods

Soybean

SDSU Extension is your partner to increase yields and improve efficiency.

Soybean cyst nematode symptoms.

Know Soybean Cyst Nematode, Numbers Matter!

Have you noticed parts of your soybean field turning yellow earlier than expected? Are some of the plants stunted or showcasing a roller coaster appearance? Soybean cyst nematode may be to blame.

Three soybean diseases. Brown spot, Phytophthora Root Rot, and white mold.

Mid-to-Late Soybean Disease Management

Even though it has been hot and humid this summer, some soybeans around the state have seen ideal conditions for mid-to-late season disease development. Learn some common diseases to scout for.

Hail-damaged corn field.

Are Fungicides Needed on Crops Damaged by Wind, Sand Blasting or Hail?

When extreme weather brings hail and sand blasting to fields, many growers wonder if a fungicide application is needed afterwards to protect wounded plants from bacterial diseases.

Hand holding a dead early-planted soybean seed.

Risks of Early Soybean Planting in South Dakota

Early soybean planting offers potential yield benefits, but it also poses some risks. Learn some expert tips and considerations for early soybean planting this growing season.

A portion of a soybean field with soybean plants maturing with the soybean leaves turning yellow with the leaves and stems drying down.  The plants in the middle of the picture were also found with charcoal rot.

Charcoal and Fusarium Rots Observed in Early Senescing Soybean Plants

The drought conditions in South Dakota have led to early soybean senescence in some areas. However, some of the early senescing may be due to dry-season diseases, such as charcoal and Fusarium rots.

Young farmer examining soybean plants n a field at sunset.

Be Aware of Fungicide Resistance in Field Crops

A few soybean and corn fields have received or will be receiving a fungicide application this season. We recommend scouting fields treated with fungicides to determine if diseases are controlled as expected or if there are signs of reduced sensitivity.

Green soybeans with yellowing throughout.

Bacterial Blight Developing In Some Soybean Fields

Bacterial blight was found developing in a few soybean fields scouted the week of July 19. Leaf tattering is a common symptom of bacterial blight and happens when expanding bacterial blight lesions coalesce and form large brown patches.

A soybean plant with wilting leaves due to stem canker surrounded by healthy soybean plants.

Stem Canker Developing in Some Soybean Fields

A few soybean fields are showing some wilting plants due to stem canker. The field entries and head rows are the most-impacted parts of these fields. The current dry conditions are stressing the plants and causing early development of the disease.