Investigating New Management Approaches for Picture-Winged Flies in Sweet Corn

View the project final report

• 2016 annual report

Commodities

• Vegetables: sweet corn

Practices

• Pest Management: chemical control

A group of picturewinged flies, referred to as silk flies, are severe primary pests of corn grown in Florida and in Central and South America. Females oviposit in developing ears, and larvae consume silks and kernels, rendering the ear unmarketable. Current management relies solely on numerous broad spectrum insecticide applications, especially pyrethroids. Alternative management tactics need to be evaluated in order to mitigate potential for insecticide resistance development and to reduce environmental costs. Crop destruction is an important integrated pest management tactic that reduces fly populations by eliminating developing larvae after harvest. This project will evaluate three methods of crop removal for their efficiency at reducing silk fly adult emergence. Reduced-risk insecticides mixed with a sucrose feeding stimulant will be investigated and compared to a grower standard treatment. At the same time, flies treated with conventional pyrethroids in the field will be collected and returned to the lab to evaluate silk fly recovery, an indication of resistance development. Finally, water sensitive paper will be placed in a corn canopy to determine how different application techniques influence canopy penetration. Combining optimal sprayer settings, alternative insecticides, insecticide resistance monitoring, and efficacious crop removal will help growers manage sweet corn more sustainably.

1. Determine most efficient and timely means of crop residue removal to reduce silk fly production
2. Determine if the reduced risk insecticide spinetoram can be applied in a bait to provide adequate fly control
3. Determine if silk flies demonstrate reduced pyrethroid susceptibility in field settings
4. Determine how insecticide application methods can be improved for increasing canopy penetration