Southern root-knot nematode is causing problems in the Southeast, according to John Mueller, a Clemson University professor. Root-knot nematodes can cause severe reduction in soybean yield, worsen injury caused by other fungal diseases and cause plant death.
“There are several nematode species that cause economic damage, such as soybean cyst, southern root-knot, peanut root-knot, Columbia lance, reniform, sting and lesion,” he says “Of these, the most well-known is soybean cyst, but in the southern part of the country, southern root-knot probably causes the most damage across the greatest acreage.”
In a recent “Focus on Soybean” webcast,  Mueller discusses the differences between these two most common soybean nematodes, along with management practices for all nematode species.
He suggests four practices to help minimize nematodes’ effect on soybean yield:
- Soil sampling — Farmers should take soil samples after harvest. By doing so, you can determine which type of nematode you have.
- Crop rotation — Once you know which nematodes are present, you can determine the crops affected by the nematode species in your field and plan a crop-rotation schedule accordingly.
- Use resistant varieties — If you know which nematode species, and in the case of SCN which HG types or races, live in your fields, you can select soybean varieties resistant to those nematodes.
- Use of a nematicide —Use this method when there are multiple species of nematodes present in a field or when you have a species of nematode for which no resistant variety exists. Nematicides are available in granular or fumigant forms, chemical or biological seed treatments and harpins, which induce resistance in plants.
The soy checkoff supports the “Focus on Soybean”  webcasts through a partnership with the Plant Management Network. All U.S. soybean farmers have access to this full presentation until April 14, a shorter executive-summary version of the presentation will be available indefinitely after that time.