By Andi Anderson
Sugarbeet root aphids have become a growing concern for Michigan sugarbeet producers as infestations continue to increase across the state's production region. The pest feeds primarily on the secondary roots of sugarbeet plants, reducing their ability to absorb water and nutrients efficiently. As a result, growers can experience lower yields, reduced sugar content, decreased recoverable sugar, and poorer storage quality.
Root aphids reproduce rapidly because the population consists entirely of females that can produce live offspring without mating. Multiple generations can develop on sugarbeets during a single growing season, allowing populations to increase quickly under favorable conditions.
One of the most common signs of a heavy infestation is the appearance of wilted sugarbeet canopies in circular patches throughout a field. When affected roots are dug up, growers often find yellowish-green aphids along with distinctive white waxy secretions surrounding the roots. These waxy deposits help protect the insects from moisture and physical damage while they live in the soil.
After harvest, sugarbeet root aphids can survive the winter on sugarbeets left in the field or on related weed species such as common lambsquarters and redroot pigweed. Because these weeds can act as alternative hosts, effective weed control throughout the crop rotation can help reduce aphid survival and future infestations.
Plant resistance remains one of the most important management tools available to producers. Sugarbeet breeding programs continue to evaluate and develop varieties with improved resistance to the pest. When infestations become severe, growers may also consider systemic insecticides containing spirotetramat, the active ingredient found in products such as Boxadon 360 SC and Movento.
To better understand control options, Michigan State University researchers established replicated field trials during the 2026 growing season. These studies compare standard seed treatments with additional spirotetramat applications later in the season. Researchers are evaluating effects on both yield and sugar production while also studying the effectiveness of rescue treatments in heavily infested fields.
Natural enemies also play a role in suppressing root aphid populations. Larvae of the chloropid fly Thaumatomyia glabra feed on aphids below ground, while beneficial fungi infect and kill aphids later in the season. These biological controls provide valuable support but are often unable to prevent outbreaks when aphid populations increase rapidly.
Root aphid infestations have been significantly more common during the 2025 and 2026 growing seasons than in previous decades. Experts are still investigating the reasons behind this increase. Extended periods of hot, dry weather during July and August may have favored aphid development. Other possible factors include changes in weed host populations or shifts in the effectiveness of current resistance traits.
To address the problem, sugarbeet seed companies, Michigan Sugar Company, Michigan State University Extension, and the USDA are working together to monitor fields, collect data, and conduct research. Their efforts aim to develop improved management strategies and better understand the causes of these recent outbreaks.
As research continues, growers are encouraged to scout fields regularly, manage weed hosts effectively, and utilize available resistance and control options to reduce the impact of sugarbeet root aphids on crop productivity and profitability.
Photo Credit: gettyimages-luiscarlosjimenezi
Categories: Michigan, Crops, Sugar Beets, Sustainable Agriculture