Bt and Monarchs



Monsanto Statement on Bt Corn: Envrionmental Safety and a Recent Report on the Monarch Butterfly

PR Newswire
May 20, 1999

ST. LOUIS, May 20 /PRNewswire/ -- "Bt corn" refers to corn that has been enhanced through plant biotechnology with a trait that protects it from damage against specific insect pests. Because of a protective protein that the corn produces, it is not damaged by insects like the European corn borer, which can have devastating and irreversible effects on corn crops.

Prior to the introduction of Bt corn, farmers typically controlled insect pests with conventional insecticides that get rid of both those damaging insects, as well as the beneficial and desirable insects (e.g., those that help control other pests that harm plants or spread plant diseases) present in the field. An important advantage of Bt corn is that these sprays are either reduced or eliminated; as a result, the effects on beneficial and other non-target insects also are dramatically reduced or eliminated. By reducing the use of broad- spectrum insecticides, Bt corn reduces the potential to harm non-target and beneficial species, and it reduces the impacts of agricultural inputs on the environment in general.

Nature Article

The May 20 issue of the journal Nature reports on a laboratory study conducted by Cornell University researchers that asserts a negative impact of milkweed dusted with pollen from Bt corn on the growth and survival of the non-target Monarch butterfly.

We take very seriously research on Monarch butterflies and other non-target species, as well as beneficial insects that help control pests in fields. Considered in total, research conducted in the field supports the safety of Bt crops for beneficial and other non-target insects. The laboratory study in Nature provides interesting information, but reflects a situation very different than that actually prevalent in the natural environment.

Monarch larvae feed almost exclusively on milkweed. The natural habitat for milkweed is prairies, fields and roadsides, not the middle of full grown and pollinating corn fields. In real life situations, the exposure of milkweed to corn pollen is very low because only a very small portion of milkweed grows in close enough proximity to corn fields for exposure to corn pollen. This information supports the conclusion of a very low likelihood of effect of Bt pollen on non-target insects like the Monarch butterfly in their natural habitats.

The principal author of this laboratory study has cautioned against drawing conclusions until more research and data have been collected and studied. Monsanto is very supportive of initiatives that lead to better understanding of insect-protected crops and non-target and beneficial insects. To that end, we are participating in an industry effort to support additional field research to reaffirm the lack of impact of Bt crops for these insects in their natural environment. We will continue to cooperate with researchers and the industry to support studies aimed toward better understanding of insect- protected crops.

Additional editors' reference notes:

  • Over 40% of all chemical insecticides used in the United States are used on cotton plants. Use of Bt insect-protected cotton has eliminated the use of nearly 1 million gallons of broad spectrum chemical insecticides since it was first commercially grown in 1996. (1996: 250,000+ gallons, 1997: 300,000 gallons, 1998: 300,000+ gallons)

  • According to a University of Alabama study the adoption of Bt cotton has reduced chemical insecticide use in their state to the lowest levels in over 40 years since the introduction of these chemical insecticides.

  • In 1998 use of Bt insect-protected corn reduced or eliminated the use of broad spectrum chemical insecticides on some 15 million acres of U.S. farmland.

  • Farmers growing Bt insect-protected potatoes on nearly 40,000 acres have reduced their chemical insecticides use by over 40%.

Additional expert contacts:

Galen Dively, 301-441-1088
University of Maryland Professor of Entomology
4112 Plant Science Building
College Park, MD 20742

John J. Obrycki
Iowa State University
7 Insectory Drive
Ames, IA 50011
515-294-8622

** NOTICE: In accordance with Title 17 U.S.C. Section 107, this material is distributed for research and educational purposes only. **



Last Updated on 5/25/99
By Karen Lutz
Email: karen@biotech-info.net

What's New?
Home
Environmental Impacts