Soybean producers are encouraged to examine roots of soybean plants that exhibit yellowing of leaves this year. If roots are infested with small, white insects, report these findings to Mike Gray, University of Illinois Extension entomologist. They could be trochanter mealybugs.

Trochanter mealybugs are root feeders that remove fluids from plant tissue with their piercing and sucking mouthparts. The host range for trochanter mealybugs is large and includes many legumes such as alfalfa, red clover, white clover and soybeans. They have also been collected from corn, johnsongrass and sorghum.

“In 2008, trochanter mealybug infestations were reported in the August 25 issue of the Kentucky Pest News,” Gray says. “Last year, an Ohio State University Extension entomologist reported infestations in fields where a potassium deficiency was suspected due to the yellow coloration on leaves.”

At this point, it remains unclear if trochanter mealybugs will emerge as a new management challenge for soybean producers. But Gray recommends that producers keep a close eye out for these insects.

Gray says if he receives numerous reports, a more formal survey may be initiated in the future.

For more information, check out The Bulletin, an online publication written by U of I Extension crop science specialists.