Biological Control of European Corn Borer in Peppers

Posted: November 4, 2011

There are many factors that must be considered when making a pest control plan. Some of those factors are the biology of the pest, how pest damage impacts the value of the crop, the time it takes to apply controls, the cost of the control, how marketing impacts the use of pest control measures, and probably most important, is the control effective.
European corn borer in bell pepper. photo by Tom Kuhar Virginia Tech.

European corn borer in bell pepper. photo by Tom Kuhar Virginia Tech.

One pepper grower in Northeastern Pennsylvania, Lenny Burger, chose to use only the parasitic wasp Trichogamma ostriniae to control European corn borer in his 6 acres of peppers in 2011. So what were the factors that helped Lenny decide to try biological control for the first time? He knew the biology of the pest and that he had the pest on the farm. He has been growing crops for many years that are attractive to corn borers: sweet corn, peppers, and potatoes. He has been using pheromone traps to monitor sweet corn pests for about 14 years. He targeted the second generation of the European corn borer since that is the generation that enters pepper fruit. He knew that a pepper with a worm in it is not only not salable, it also negatively impacts future sales. He considered the number of crops he is growing to supply the on farm market as well as the pest control demands that come with each crop. Time is at a premium during that time of year.

He learned that the cost of using biological control was comparable to conventional insecticide control. Since most of the peppers were harvested as pick your own, it is hard to control where pickers pick. Many customers assume that when they are told not to pick peppers in a certain area it is because that is where the best peppers are and you are saving them for yourself.  Biological control eliminates the concern of peppers being picked that are still within pesticide label restricted harvest intervals. The final question was whether he could count on Trichogamma ostriniae to effectively control European corn borer in his pepper crop. Without any past experience to rely on, Lenny was taking a gamble.

Lenny spoke with Carol Glenister of IPM Laboratories in Locke, New York about his desire to use biological controls in his peppers. Carol provided a schedule of when the wasps would be sent to his farm and how they should be set out in the field. A total of seven weekly shipments were received starting on July 25 and ending on September 5. The shipments ended when the pheromone trapping indicated that the flight of adult European corn borers was over.

It took up to thirty minutes each week to place the packets containing the tiny wasps in the field. The time it typically takes to spray the same block of peppers is about 1.25 hours a week.

So what was the end result? European corn borer damage was not detected in the pepper crop. The final cost was about $189.00 per acre which is about the same as or less than the cost of seven applications of an insecticide. The time saved from not having to apply the insecticide was about 7 hours. The 7 hour saving came at a time when the work demand was intense. Additional benefits that are hard to put a dollar value on include; the fact that insecticide label restrictions did not interfere with harvest, there is no concern of pesticide residue on the fruit, resistance management is not a concern, and there are no ruts through the field caused by pulling the sprayer through a field saturated by hurricane Irene and tropical storm Lee.

It is important to point out that this is the experience of one grower in one year. It is not replicated research. Hopefully this growers’ experience will give other growers the confidence to incorporate biological controls like the Trichogamma ostriniae into their pest management plans. Start out small. Gain knowledge and experience before expanding.