(Pioneer/Dupont)--Soybean cyst nematode (SCN) is the single most damaging soybean pest in the United States. This pest may decrease yields substantially without inducing obvious symptoms. Soil sampling strategies for SCN vary, depending on the history of the pest in the field. In fields without symptoms or known history of SCN, DuPont Pioneer agronomists suggest soil sampling in the fall when SCN numbers are highest.
For growers without a known SCN problem, sampling fields without symptoms every 4-6 years is the only way to detect these pests before becoming an economic problem. When sampling, target areas likely to be introduction points for SCN such as entryways, fence lines, areas prone to flooding, and consistently low-yielding areas. If SCN is found, use the predictive sampling procedure to determine egg or cyst numbers before planting soybeans again.
SCN requires a combination of strategies for effective control. Soil sampling, clean equipment, crop rotation and selecting resistant varieties will help protect against SCN. Additional management practices — such as avoiding low fertility, compaction, drought stress and other disease or insect pressure — promote good soybean health and enable plants to better withstand the effects of SCN.
Pioneer soybean breeders are intensifying their efforts to develop more, improved SCN-resistant varieties. In the future, Pioneer soybean breeders expect additional as well as better varieties to counter the increasing pressure from SCN.