Beyond SCN: Soybean nematode pressure

Published on: 16:37PM May 07, 2010
David Long
Most soybean growers are aware of Soybean Cyst Nematodes (SCN). But there is another group of nematodes that feed on soybeans. Non-cyst-forming nematodes include root-knot, reniform and lance nematodes. And they nibble on soybean roots, as well.
Remember, nematodes are microscopic, thread-like, non-segmented worms that live in soil and feed on plant roots. Plant parasitic nematodes are tiny – barely more than a millimeter long – and translucent. That makes them invisible to the naked eye.
Although many soybean varieties now have SCN resistance, SCN still accounts for significant soybean yield losses, especially across the southern United States. However, root-knot and other non-cyst forming nematodes may be considered a bigger threat, because they are more difficult to manage. 
Most of the non-cyst forming nematodes also attack rotational crops such as cotton and corn. Since there are few rotational options and limited resistant soybean germplasm, management of these nematodes may require a nematicide.
(Photo: Juvenile root-knot nematode entering root gall.)