Stay Ahead of Sudden Death Syndrome for 2025

Protecting against Sudden Death Syndrome (SDS) starts before planting season. But before we can talk about management, let's take a look at what causes SDS and how to identify it.

📷 BASF Employee | illustrating SDS foliar symptoms included interveinal necrosis

Symptoms

● Although infection initially begins in the root, the first observed symptoms are often on the leaves.

● At the beginning foliar symptom stages, yellow spots begin between the leaf veins, resulting in interveinal chlorosis. Veins remain green.

📷 BASF Employee | illustrating Foliar symptoms of SDS start as interveinal chlorosis, as the disease progresses the lesions expand and turn brown

●As the disease progresses, lesions expand and turn brown between the veins, resulting in interveinal necrosis. Veins remain green as the disease progresses, the lesions will expand and turn brown

📷 BASF Employee

●In the final stages, the leaves die prematurely and fall off leaving the petioles attached to the plant. Pods and seeds become aborted resulting in yield loss.

● In wet soils the SDS fungus can reproduce resulting in a mass of blue spores on the root.

● Brown stem rot has a similar foliar appearance to SDS. To differ between them, split the stem and observe the pith. If the pith is brown and discolored, the disease could be brown stem rot. If the upper portion of the stem pith is white, it is more likely SDS.

📷 BASF Employee

SDS and Brown Stem Rot have similar foliar symptoms, one way to differentiate is look for the more characteristic white pith in the upper portion of the stem associated with SDS. Plants with Brown Stem Rot will have a brown pith.

Environmental Conditions Favoring Disease

● Cool, wet field conditions in the spring  increase chances of the initial root infection

● Frequent and/or heavy rains midseason result in foliar symptoms appearing

● The presence of Soybean Cyst Nematode (SCN) can exacerbate the disease

Disease Management

SDS must be controlled with preventative tactics, as foliar fungicides are not effective. Plant a variety with resistance (many Xitavo varieties offer tolerance to SDS), manage SCN, and use ILEVO® seed treatment. Rotating to corn typically does not reduce SDS in following soybean crops, because the fungus is able to survive on corn residue.

Ilevo is a registered trademark of BASF. Xitavo is a registered trademark of M.S. Technologies, L.L.C., Xitavo soybean seed is exclusively distributed by BASF..