Aphid populations surged in Illinois fields last week, particularly in June-planted corn.
“They like a higher sugar load, so that’s why the June hybrids are getting hit hard,” explains Ken Ferrie, Farm Journal Field Agronomist and owner of CropTech, Inc., near Heyworth, Ill. “Some of the fields that were mildly affected on Monday were blown apart by Friday,” he adds.
Aphids are “tasters,” meaning they sample corn from field-to-field until they find hybrids that provide the amount of sugar desired. They then typically settle into that field and feed. That desire for sugar is why farmers often find one field of their corn is loaded with aphids, while the one next to it isn’t.
While an aphid infestation is bad enough, Ferrie also saw Goss’s wilt in some of the same fields this past week and suspects aphids are a vector for the disease--though insects are not a confirmed factor in the spread or development of it.
“Because Goss’s wilt is a bacterial disease it can’t get into the leaf on its own; it needs an entry point,” he notes. “Thousands of aphids sticking their noses into the corn are the perfect tool for that.”
In the following podcast, Ferrie addresses how to manage aphids yet this season as well as cultural practices farmers can use in 2020, along with hybrid selection, to sidestep Goss’s wilt.