Soybean farmers with plants that have emergence issues should consider that seedling blight diseases might be the cause, a Purdue Extension field crops pathologist says. This would especially be the case in fields that were planted before the cool, wet conditions that persisted across Indiana in recent weeks, Kiersten Wise said. “Several different organisms can cause seedling blight diseases under a range of environmental conditions,” she said. “There are several different seedling blights that can occur in soybean, and, unfortunately, they are difficult to diagnose in a field.” Symptoms include wilting or discolored seedlings, poor stand establishment and seedlings with discolored or rotted roots.
Wise said farmers who suspect that their plants have seedling blight should submit samples to a diagnostic laboratory such as the Purdue Plant and Pest Diagnostic Laboratory for testing. That would either confirm the disease or determine that the problem might be the result of herbicide injury or simply too much moisture. A video with Wise and Gail Ruhl, senior plant disease diagnostician at PPDL, showing farmers how to properly take samples from their field and submit them for testing is available at https://extension.entm.purdue.edu/pestcrop/2016/issue6/.
The website includes links to publications, sponsored by the North Central Soybean Research Program and United Soybean Board, that can help farmers and agribusiness staff understand and manage soybean seedling diseases.
More information about the Purdue PPDL is available at www.ppdl.purdue.edu.