US using less pesticides on sweet corn with biocontrols

In the US EPA-funded project, Cathy Thomas, PA IPM Coordinator at the Pennsylvania Department of Agriculture and biocontrol specialist, is focusing on corn earworm, a major pest of sweet corn. "The larvae damage the fruit of the plant by first feeding on the silks, hindering pollination, and later by feeding on the kernels inside the ear," she explains.

Farmers feel pressure to use multiple applications of broad-spectrum pesticides because there is little consumer tolerance of worm-damaged corn. But heavy pesticide use can have serious affects on the farm environment and surrounding areas and can cause insects to be resistant to insecticides. According to Thomas, the goal of the project is to reduce or eliminated broad-spectrum pesticides to control corn earworm by training growers to use IPM and biocontrols.

IPM, or integrated pest management, aims to manage pests -- such as insects, diseases, weeds and animals -- by combining physical, biological and chemical tactics that are safe, profitable and environmentally compatible.

Thomas has been working with three Amish farmers in York county who were interested in IPM and reduced spray programs. "They all have farm markets and take produce to the local produce auction, so it's important the corn be marketable" says Thomas. "The standards for produce sold at auction and roadside stands are very stringent, purchasers want vegetables to be free of blemishes."

Thomas is helping growers incorporate biocontrols such as the parasitic wasp,Trichogramma pretiosum  and other biological treatments. She is also educating growers on the identification and life cycle of corn earworm and other sweet corn pests. Additionally, the project team is producing educational posters and brochures to help consumers and retailers understand that produce grown with fewer pesticides may result in some worm damage, but will be better for farm worker protection, consumers and the environment.

Thomas explains that many Amish and Mennonite farms are family operated and children often participate in harvesting and maintenance in the fields, risking potential pesticide exposure. "Pesticide reduction or elimination will make farm environments safer for the children, other family members and farm employees.   Also, there is less risk of pesticide runoff in local water ways, local pollinators won't be harmed by excessive pesticide use, resistance to pesticides will be reduced, and the surrounding communities will be pleased to know that there are fewer high-risk pesticides being used in their region," she says. Also, the project promises to be more economical. "Farmers will save money they would spend on chemicals and should be able to draw a higher price for produce grown with reduced pesticides."