A rare, invasive aphid has been found attacking wheat crops in Hampton County, South Carolina.
This is the first documented case of the Sipha maydis aphid in South Carolina, said Francis Reay-Jones, an entomologist at the Clemson University Pee Dee Research and Education Center in Florence.
More commonly found in Europe, Asia and parts of Africa, the Sipha maydis aphid has been moving eastward since its first U.S. sighting in California in 2007. The invasive pest was found in a Georgia greenhouse in 2012 and in an Alabama wheat field last year.
In South Carolina, the aphid was spotted by Clemson University Extension agent Andrew Warner on both rye cover crops and wheat, though they were more abundant on the wheat, Reay-Jones said. A taxonomist confirmed Warner's discovery.
"The insect has been reported to feed on a range of grass hosts, including wheat, oats, barley, johnsongrass, sorghum and corn," he said. "The insect is of particular concern in small grain crops as it can transmit barley yellow dwarf virus."
Sipha maydis aphid -Image Credit: Melissa Franklin / Colorado State University
The aphid feeds on leaves, which can cause them to become chlorotic, a yellowing or whitening of leaves due to insufficient chlorophyll, Reay-Jones said. This reduces plant growth.
Little else is known at this point about this uncommon pest, including control methods, he said.
"While it's been found in some wheat and oat fields in Alabama, it hasn't yet become a major issue over there, so it's hard to predict how much of an issue this insect will be for us," Reay-Jones said.
Growers should scout their fields for this pest and contact their local county Extension agent for help. The Sipha maydis aphid is identifiable by its dark color and the white hairs on its abdomen.