Early season popylation dynamics and impact of seed treatments on bird cherry-oat aphid, Rhopalosiphum padi in Arkansas winter wheat

A study was conducted to determine the duration of efficacy of the insecticidal wheat seed treatment Cruiser® on the bird-cherry oat aphid. This paper presents the data from the field portion of the study, which monitored insect immigration using yellow pan traps and evaluated dynamics of aphids on plants in treated and untreated plots. The results clearly show that the seed treatment is effective in the first two weeks, significantly reducing aphid densities. While densities continued to be significantly reduced in treated plots for more than a month after plant emergence, the difference can be attributed to the lack of significant new immigration into the plots after the insecticide efficacy declined. Controlled greenhouse studies are underway to pinpoint the duration of efficacy of the insecticide as influenced by soil type.