A recent study conducted in the Department of Entomology has raised questions regarding the usage of a specific type of genetically modified corn.

Bacillus thuringiensis (Bt) corn was genetically engineered to be resistant to pests, specifically European corn borers.

It was developed in the 1990s with the hopes of reducing insecticide use in corn fields.

The new study conducted by John Obrycki, professor of entomology, indicated the increased planting of Bt corn in Iowa has not reduced insecticide usage or increased crop yields as originally hoped.

Obrycki came to this conclusion with the help of graduate assistant Laura Jesse and Cornell University entomologist John Losey.

Their paper, published in the May edition of BioScience, addresses issues relating to Bt corn, such as its ecological effects, rates of insecticide use and overall corn yields.

“I do believe that this technology has many benefits for agriculture, but this specific use might not be the best use of the technology,” Obrycki said.

He said many people overuse Bt corn because they consider it a safe alternative since it occurs naturally in fields.

“Bt is naturally occurring, but it is packaged completely differently in modified Bt corn,” Obrycki said.

“It seems that farmers use this technology as a preventative measure, but they may not be getting any economic return.”

Obrycki said his main purpose in conducting this study was to create awareness for farmers.

“Farmers will make their own decisions relative to planting genetic plants,” Obrycki said. “I am trying to assess the research and present the facts.”

The study also took a look at the effects of Bt corn on Iowa’s monarch butterfly population.

Obrycki’s lab and field studies showed higher levels of Bt pollen in the air have some minimal adverse effects on monarchs.

These effects occur mainly because Bt corn affects milkweed plants, which is a primary food source for these butterflies.

Bob Hartzler, professor of agronomy, said his studies have shown that half of the country’s monarch butterfly population originates in the Midwest.

Since the butterflies prefer to lay their eggs on milkweed plants growing in corn and soybean fields, research needs to be done on Bt corn’s impact.

“If Bt pollen has an impact on the growth of milkweed it is relatively small,” Hartzler said.

“But it could cause additional stress on the monarch population in light of their already high mortality.”

Bill Shimon, president of Agriculture and Investment Management in Perry, is skeptical of the latest Bt corn findings.

“From my own experience, I haven’t used as much insecticide for corn borers recently,” he said.

“So I will use Bt corn initially and only use insecticide as a last resort.”

Shimon also said people need to be less critical of farmers because they aren’t trying to harm the environment.

“If more research finds that Bt corn has significant negative effects on the environment, then I will stop using it,” Shimon said.

“People need to remember that farmers live with the environment. It is their livelihood and they don’t want to destroy it.”