By David Wishowski
Sugarbeet root aphid populations have been increasing across the Michigan growing region. Root aphids primarily feed on secondary roots, inhibiting the plant’s ability to properly absorb water and nutrients. This results in direct loss in tonnage, sugar content, recoverable sugar and storability.
Several generations of sugarbeet root aphid occur on sugarbeets in a single season because they are all female, reproduce without mating, and give birth to live young. A heavy root aphid infestation often shows up as a wilted canopy in circular patches throughout the field. When roots are dug in one of these patches, white waxy secretions are visible (often remaining even after a rain event) along with the yellowish green aphids (Photo 1). Root aphids secrete this wax to repel water and protect themselves from physical damage in the soil.
After harvest in Michigan, sugarbeet root aphid overwinters on beets left in the ground or on roots of related weeds in the amaranth plant family, such as common lambsquarters or redroot pigweed. Good weed control across the entire crop rotation can reduce these alternate hosts and long-term root aphid survival.
Sugarbeet breeding programs screen varieties for genetic resistance to sugarbeet root aphid as a primary defense against this pest. In the absence of host plant resistance or during a root aphid outbreak, the systemic insecticide spirotetramat—the active ingredient in Boxadon 360 SC and Movento—may be an option for control.
During the 2026 growing season, Michigan State University established replicated strip trials (6-8 rows by at least 1,000 feet) comparing Cruiser 5FS seed treatment (thiamethoxam) with Cruiser 5FS plus spirotetramat applied later in the season. Researchers will evaluate both yield and sugar content at harvest. Additional research trials of similar design were established to evaluate the efficacy of spirotetramat as a rescue treatment in fields with infested areas later in the season.
Source : msu.edu