This year’s drought conditions may hold one benefit for soybean producers: a better opportunity than most years to scout for the elusive soybean cyst nematode (SCN).
Damage due to soybean cyst nematode typically does not show any above ground symptoms, especially with normal conditions for soybean production. In years with stressful conditions, especially drought stress, symptoms will be more evident.
Patches of stunted, yellow, and/or wilted soybeans could indicate the presence of SCN. The nematode population will vary across the field and will be found in dense pockets. You may see patches of soybeans that are more affected with gradients of damage extending out from a center area which corresponds to these pockets of higher soybean cyst nematode. This will look much like a low spot in the field that has a root rot problem.
Other clues for the presence of SCN include, good corn yields with soybean yields hitting a plateau or even dropping over time. This combined with any symptoms in drought is a strong indication that SCN may be present in your field.
If you see these symptoms and have not tested for SCN in your fields, consider collecting soil from these sites. The Nebraska Soybean Board is funding a free sample program. Send in your soil sample to receive have it tested and determine the egg density in your field. Further information and sample bags are available from your local UNL Extension office or by calling (402) 472-2559.