PMN Crop News Homepage   

Posted 27 August 2012. PMN Crop News.

Soybean Aphids: a Late-Season Game-Changer

Source: Syngenta Crop Protection-US Press Release.

Greensboro, North Carolina (August 1, 2012)--Hidden within the soybean canopy is a tiny but highly destructive pest known as the soybean aphid. This pest can destroy your soybean field before exhibiting a single trace of evidence. Leaving no visible feeding scars, soybean aphids threaten to significantly reduce soybean yields by feeding on the stems and undersides of soybean leaves. Because of the lack of evidence, these inconspicuous insects are difficult to detect before they have reduced yields.


Soybean aphids can appear on soybeans through pod fill and can quickly reach damaging economic thresholds if left uncontrolled. Aphid populations fluctuate due to weather, predatory feeding, disease and plant stress. During favorable conditions, populations can double every two to three days. Soybean aphids have the ability to cover an entire field due to their rapid population growth, significantly impacting yields and profits.

Soybean aphid reproduction is slow in hot dry environmental conditions. Based on this, the 2012 season should be a light year for infestations. However, when the weather pattern becomes more favorable for aphid reproduction, aphid numbers are still expected to rise in late summer/early fall.

“Soybean aphid pressure hasn’t been too high yet this growing season,” said Troy Griess, agronomic service representative, Syngenta. “However, in Minnesota and parts of Iowa, some growers are already seeing these pests in their fields. Soybean aphids become a problem when they reach the economic threshold of 250 aphids per plant in 80 percent of your field and need to be treated properly.”

Keeping ahead of the pest is vital, and Syngenta agronomists, such as Griess, want to help. New in the Midwest this year is an easy way for growers and retailers to stay on top of migrating soybean aphid populations. The Syngenta Pest Patrol program offers season-long pest updates and treatment recommendations, including information on soybean aphid patterns from agronomists, through its toll-free hotline (877-285-8525), text alert service and website ( The program is available to more than 20 regions throughout the South and the Midwest.

“The Pest Patrol program can help growers and retailers stay ahead of pest pressures in their area in addition to offering specific treatment recommendations provided by university entomologists and agronomists,” said Griess.

Wendell Calhoun