Seed Treatment Alternatives

Seedcorn maggot (Delia platura) is a pest of economic significance in large-seeded crops like soybeans and corn, with the potential to dramatically reduce yield in fields with high organic matter. Traditional mitigation efforts rely on the use of neonicotinoid seed treatments, prompting New York State Integrated Pest Management to initiate research projects designed to assess the potential efficacy of alternative treatments. 

Under the direction of Field Crops and Livestock Coordinator Kenneth Wise, NYSIPM launched a series of trials to evaluate the success of the anthranilic diamide Chlorantraniliprole and Spinosad seed  treatments in controlling seedcorn maggot. Both claim to be effective against the pest, while posing significantly less risk to non-target species, including pollinators. Spinosad is also labeled for organic production. 

Ten trials were conducted in four locations across New York in 2022, with limited year-one data revealing little difference in the effectiveness of the traditional or alternative treatments. 

Year two research will be expanded to include 12 to 16 trials in seven locations and will explore the efficacy of traditional neonics, fungicide, diamides and untreated seed. 

Progress Report

NYSIPM conducted ten trials at research plots in Willsboro, Chazy, Cobleskill and Canandaigua, NY during the 2022 growing season. Canandaigua and Cobleskill played host to one trial each, while Chazy and Willsboro hosted four trials, each planted one week apart.  

Cobleskill

The trial plot was planted on May 25 with data collection occurring on June 3. Unfortunately, much of the corn was fed on by crows, reducing plant populations and the potential for the development of seedcorn maggot infestation. As a result, the data collected at SUNY Cobleskill was not used in the year-one analysis. 

Canandaigua

The Western New York site was planted on May 20, with data collection taking place on June 3. No significant differences between treatments and control were observed, and the site saw almost no seedcorn maggot infestation. 

Willsboro

Four trials were planted one week apart in Willsboro in an effort to capture the peak flight of the seedcorn maggot fly. The first trial, planted May 27, with data collection on June 8, revealed no significant difference between treatments but did reveal extensive seagull damage. The second trial, planted June 3, with data collection on June 18, captured no significant differences in the treatments. The third trial, planted on June 10, with data collection on June 18, resulted in no significant findings related to the treatments but also saw bird damage. The final trial, planted June 15, with data collection on June 27, revealed significantly more damage in the plots treated with neonicotinoids compared to the other treatments.  

Chazy

At the Northeastern border of New York State, Chazy hosted four trials planted one week apart. The first, planted May 23, with data collection on June 8, revealed no significant difference between the treatments. The second trial, planted May 31, with data collection on June 18, mirrored the fourth trial in Willsboro, with significantly more damage occurring in the plots treated with neonics. The third and fourth trial, with June 9 and 13 plantings and June 18 and June 27 data collection, respectively, revealed no significant differences between the treatments. 

Year-One Findings 

Once the data from all sites was pooled and a multivariant analysis conducted, it was determined that there were no significant differences in any of the treatments, meaning that overall, seedcorn maggots were not a factor in establishing corn in any of NYSIPM’s year-one trials.