The above photo shows how severe soybean cyst nematode pressures can affect a non-cyst resistant soybean variety.Growers should be testing their fields long before reaching this stage of Soybean cyst nematode injury.Soybean cyst nematode infection doesn't have to look anywhere close to what these shots show before significant yield losses can occur.Rotation and the selection of a good cyst nematode resistant variety can prevent such a problem from ever occurring.
Undetected Soybean cyst nematode injury is still rated as the #1 yield robber in soybean production across North America today.Its estimated that growers lose roughly $1 Billion dollars from this devastating disease annually.Once cyst levels reach 1500 + eggs per 100 grams of soil fields can start to show a rolling
affect like that in the shot above.There has been much historical evidence to show that fields can appear to look perfectly healthy and yet still have cyst infection in their roots.THATS WHY SOYBEAN CYST NEMATODE IS OFTEN REFERRED TO AS THE SILENT YIELD ROBBER.
Soybean leaves will start showing a definitive yellowing to their perimeter leaf edges as nodule formation in the roots is severely curtailed and nitrogen production limited.The end result is leaf yellowing much like that of corn firing from N shortage.Not all of this yellowing may be the direct result of less nodule formation and less N-fixation by fewer functioning nodules.Some of it may be the direct result of poorer root development and less potash uptake from the soil profile.Other detrimental soil pathogens that can infect soybean roots as a result of soybean cyst infection are Brown Stem Rot and Sudden Death Syndrome.
The field above shows a more moderate infection of SCN ( soybean cyst nematode )Yield losses with this kind of visual expression can still run 8-10 + bu per acre.
These shots again show how yellowing can occur along the plants leaf margins when cyst pressures are high and a non cyst tolerant soybean variety is grown.The good news for growers is that their fields don't ever have to look like this.They can be managed.Between good crop rotations and the selection of high yielding cyst nematode resistant varieties growers can produce high yielding soybean crops that have very little to no yield loss from cyst nematodes.
If you have any suspicions about any of your fields or you want to learn more talk to your Pioneer sales rep today.Pioneer has a number of excellent performing cyst nematode resistant varieties on the market today.Soybean Cyst Mematodes have been detected in most Southwestern Ontario Counties.Anything that can cause soil movement from one farm to another can cause cyst movement.ie wind erosion,soil movement on birds feet,human transfer through soil on boots,soil movement through machinery via auction purchase,custom work etc.