Soybean Cyst Nematode (SCN) is present in soybean fields across 30 states and causes about $1.5 billion in economic loss to U.S. soybean farmers annually. This microscopic roundworm is virtually invisible to the naked eye and attacks soybean roots, reducing the plant’s ability to utilize nutrients.
SCN females form cysts after completing their life cycle, and these cysts contain eggs. When eggs hatch, the worm-shaped juveniles immediately seek to enter plant roots and begin feeding.
| Ways SCN Can Negatively Impact Yield
|
“After penetrating the soybean roots, juveniles move through the root until they contact vascular tissue in the center of the root,” said Professor of Plant Pathology Greg Tylka, Iowa State University Extension. “There, they stop and start to feed. The nematode injects secretions that modify soybean root cells. This turns them into specialized feeding cells for the nematode.”
SCN can go through three to five generations per season, each able to damage root systems. Affected plants cannot use nutrients and water efficiently, resulting in stunted plants with chlorotic foliage, nodule reduction and fewer nitrogen-fixing bacteria (see Figure 1).
SCN can be hard to detect. If there are low SCN populations, aboveground symptoms may not be present and crops may appear normal. As SCN numbers increase, plants may begin to show physical symptoms and yield impact will increase.
Read more from the Focus Report:
Click here to download the complete Focus Report from Valent’s Aveo™ EZ Nematicide and INTEGO® SUITE Soybeans.


