Anthracnose, in soybeans?

August 1, 2016 4:58 PM
Blog Post

Typically anthracnose is a disease associated with corn as a leaf blight or stalk rot, or top-tie back, but there is also a soybean disease called Anthracnose Stem Blight. 

Although both diseases are caused by a fungus they are not caused by the same fungus pathogen. Anthracnose in corn is caused by the fungus, Colletotrichum graminicola, and in soybeans it is caused by Colletotrichum truncatum. 

Anthracnose stem blight may not be a common soybean disease, but periods of moderate temperatures and high humidity or wet weather provide favorable conditions for soybean plants to become infected if the pathogen is present.

Key symptoms that give this disease away are the Shepard's crooking of stems (left image below) and also the irregularly shaped red to dark-drown blotches on the stems (right image below). These images were taken in a soybean field in Washington County on July 28, 2016. 


Learn more about Anthracnose Stem Blight and how to manage it:

Spend some time scouting your crops. What diseases (if any) are you seeing? 


Rebecca Vittetoe Field Agronomist in EC Iowa

Rebecca Vittetoe is an extension field agronomist in east central Iowa. Educational programs are available for farmers, agribusiness, pesticide applicators, and certified crop advisors.

Areas of expertise include agronomy, field crop production and management of corn, soybeans, and...