One of the most challenging issues for corn producers to control in Kansas is the root-lesion nematode (RLN), according to experts at Kansas State University’s (KSU) Department of Agronomy. This is because it does its damage underground on the roots, and there are typically no identifiable symptoms aside from yield loss. Now, the KSU experts are providing insight into how corn producers can manage the problem to ensure their entire crop doesn’t go to waste.
Visible symptoms, if any, are typically limited to patchy areas of the field where growth appears to be stunted; yellowing of the crop may also occur. On occasion, roots may have lesions on them, or they may appear to be pruned.
An entire root assay may be necessary to determine if root-lesion nematode is an issue in a particular field. Optimal sampling can be conducted between V5 and V7 growth stages. When sampling is being conducted, affected plants should be dug from the soil while keeping the roots intact.
If a corn producer suspects that a field may be impacted by RLN, the experts at KSU note that there are many commercial seed treatment nematicides available on the market. However, it’s worth acknowledging that results have been inconsistent. The experts say that soybean and sorghum are effective rotation crops for controlling the most common species of RLN across Kansas.
For more information, producers can contact their local K-State Extension office. Providing photos, along with root and soil samples to the K-State Plant Disease and Diagnostic Lab, is also helpful.