Published on Monday, August 17, 2015
In Christy’s final scouting report for the summer, she discusses the Sudden Death Syndrome (SDS) she has been seeing throughout soybean fields in central Indiana. We were pleased to have Christy as our sales intern this summer and hope you have found her scouting reports informative. We wish her the best as she heads back to Purdue University for fall classes.
Sudden Death Syndrome in Indiana Soybeans
Christy Kettler | Sales Intern | Central Indiana
August 10-14, 2015
Soybeans throughout the area have shown some Sudden Death Syndrome (SDS). The fungus that causes SDS in soybeans can survive through the winter in the soil, cysts from mature soybean roots, and crop residues. When the temperatures rise in the spring, the fungi begin to infect the new roots and reproduce underground. All of this will go on without showing any symptoms. When the soybeans begin to flower, the leaves will begin to turn yellow and show mottling in the leaf tissue. This is a result of toxins entering through the roots and moving to the stem. The toxins from the fungus will not actually mobilize through a plant, even though the leaves show the first symptoms. The next phase of symptoms can be seen as the leaves start to turn brown and die off.
The symptoms that are typically seen from the edge of a field may lead to a misdiagnosis. Chemical burn or another disease may be the true cause of the yellow or brown leaves. Brown stem rot is often confused with SDS because of the very similar look. By cutting open the stem and main root of the soybean plant, you can examine the pith. If it is white or a light tan, SDS is likely the culprit. If the pith is a chocolate brown inside, brown stem rot most likely is what caused that leaf damage. Chemical damage can cause leaf discoloration as well, but this will usually have more of a distinct pattern in a field of affected and not affected plants.
SDS in Soybeans
Managing SDS can be a challenge for any farmer. Foliar fungicide applications will not help fight this disease. In furrow fungicides and planning ahead is key for controlling and preventing SDS. Choosing varieties that are more resistant to the fungus, changing tillage practices, rotating crops, and evaluating planting date are all ways to be proactive in preventing SDS in your soybeans. Work with your local seed advisor or dealer to create a plan to manage the risks of SDS in your operation.
I have more than appreciated the opportunity to share my experiences through writing. I hope that by following my reports each week this summer, you have learned a little bit and felt closer to the fields, rain, crops, insects, and other farmers through reading. A big thank you to Beck’s for such a wonderful internship.
If you have any questions on these findings or want to learn more, please contact your local seed advisor or dealer.
Author: Denny Cobb
Categories: Agronomy, N Indiana, Michigan