Pyrethroid resistance concerns and changing soybean aphid (Aphis glycines Matsumura) management: Evidence from the Midwest United States

Pyrethroid resistance concerns and changing soybean aphid (Aphis glycines Matsumura) management: Evidence from the Midwest United States



Soybean aphid (Aphis glycines Matsumura) was first detected on United States (US) farms in 2000 and is now considered the most important insect pest by US soybean farmers. Aphid infestation can result in a significant reduction in the number of soybean pods and seeds, and seed size. While farmers are advised to use diverse practices to manage aphid, they have relied heavily on the application of pyrethroid foliar insecticides. This reliance has resulted in pyrethroid control failures in the field and confirmed pyrethroid-resistant aphids. This explores how soybean farmers awareness of pyrethroid resistance has raised concerns and motivated changes in management. To accomplish this objective, we use 2021 Midwest soybean farmer survey data with a structural causal model to estimate management practice differences attributable to pyrethroid resistance concerns and awareness. Preliminary results suggest that farmers who changed their management due to resistance concerns 1) were more likely to have applied a foliar insecticide in the past five years, 2) had applied foliar insecticides more often in the past five years, and 3) were more likely to use organophosphate insecticides. The outcomes of this research elucidate factors influencing soybean farmer behavior and decision-making related to soybean aphid management while suggesting more effective insecticide resistance management practices to respond to resistance concerns. The results can also help extension specialists and researchers develop new resistance management strategies.