Soybean cyst nematode management often starts with knowing what is present in a field, but BASF’s Mike McCarville says growers should not let the process end with a soil sample and an egg count.
McCarville says farmers need to take a more active approach to SCN management, particularly as the effectiveness of some widely used sources of genetic resistance continues to decline.
McCarville says nearly all soybeans grown across the Midwest already carry some form of SCN resistance, but much of the soybean seed available to farmers continues to rely on PI 88788.
That means simply planting an SCN-resistant variety does not necessarily mean a farmer is actively addressing the specific SCN pressure in an individual field. McCarville says growers should know their numbers and work with an agronomist to determine whether changes in management are needed.
But even those SCN population numbers do not tell the entire story.
Researchers have continued learning more about the relationship between SCN, soil characteristics, and yield loss. McCarville says factors including soil texture and pH can help determine how much risk the pest poses in a particular field.
McCarville says an egg count by itself may explain only a small portion of the variation in SCN-related yield loss from field to field. Combining that information with other field characteristics can provide a much clearer picture of where the greatest risk may be.
That can also help growers identify fields where different management practices may have the greatest opportunity to make a measurable difference.
For farmers, the message is not to stop sampling for SCN. Instead, McCarville says sampling should be the starting point for understanding the pest and making more active management decisions based on the conditions in each field.
