The soybean cyst nematode (SCN) is the most destructive soybean pathogen in the United States.   In 2019, the soybean cyst nematode caused an estimated loss of over 77 million bushels in the U.S., with an estimated loss of over 2 million bushels in Kentucky. These bushels lost were worth over $673 million in the U.S. and over $18 million in Kentucky. Testing for SCN in fields is the first step in managing this important pathogen of soybean.

Beginning in the Fall of 2019 and continuing through 2021, Dr. Carl Bradley initiated a soybean cyst nematode field survey program to determine the percentage of fields in Kentucky infested with SCN and to determine the level of infestation. From preliminary results, 84% of the fields tested were infested with SCN. Of the infested fields, nearly 50% had SCN populations high enough to cause measurable yield losses to soybean (at least 500 SCN eggs per 100 cm³ of soil).

In 2021, Dr. Bradley worked with the Kentucky Soybean Promotion Board to initiate a free SCN Testing Program for Kentucky farmers, where the Promotion Board would pay for testing up to 400 samples in the state. Dr. Bradley worked closely with UK Extension County Agents to help deliver this SCN testing program to their counties. So far, 30 counties have participated in this program.  

Kentucky soybean farmers have used the results from the Free SCN Testing Program to make management decisions on their farm to help mitigate losses caused by SCN and to increase the profitability of their farm.