This decline is because of varieties with more types of SCN resistance, use of MSU-ES's nematode control programs, and naturally occurring nematode parasites. SCN was first found in DeSoto County, Mississippi, in 1957.
Infestations are most prevalent in the northeastern part of the state.
Approximately one million acres in Mississippi are infested. You should suspect SCN infestations whenever you see randomly spaced circular areas of stunted and yellow soybeans in the field. Affected plants may wilt, even with adequate soil moisture, and severely infected young plants may die. Heavy infection results in root distortion and smaller than normal root systems. The roots of such plants are generally dark and discolored, and the number of nitrogen fixing nodules is reduced.