By Brenda Cassidy, Executive Director, AGCare

The truth, as it usually does, lies somewhere in between. But there’s little doubt that crop varieties enhanced through biotechnology have significant potential for helping farmers to meet production challenges, reduce pesticide use, and maintain the quality and productivity levels their customers demand.

Most Ontario corn farmers are well-acquainted with the devastation the European corn borer can cause. Severe infestations can reduce corn yields by ten per cent or more. Damage to the Canadian corn crop in 1998 has been estimated at $40 million in reduced crop yield and quality. Genetically engineered Bt-corn, enhanced with genes from a common soil organism used as an organic pesticide for decades, provides a safe, reliable and environmentally friendly option for controlling this harmful crop pest.

As well as preventing yield losses, Bt-corn has also been shown to decrease the incidence of corn disease. When insects attack corn plants, one result is an increase in disease. This occurs because insect pests carry pathogenic fungi and predispose plants to disease development. These diseases include ear rots and stalk rots that can reduce corn yield and quality. Some of the diseases are caused by fungi that produce toxins in the grain. These toxins affect approximately 25% of grain crops.

Because Bt-corn hybrids have significantly lower levels of harmful mycotoxins, their use actually enhances the safety of food and livestock feed products.

New genetically engineered corn varieties will provide protection against a new type of corn rootworm that cannot be controlled through crop rotations. Many farmers have used rotations as an effective alternative to soil-applied insecticides, and few would look forward to reverting to the heavy use of chemical alternatives to protect their crops.

Other new Bt-corn hybrids now in development are expected to help provide better control of other kernel-feeding insects, and thus provide even better protection from insect-associated fungi. The availability of these improved crop varieties to control insects and diseases would seem far preferable to the use of foliar insecticides in terms of both human and environmental safety.

Studies released over the past few months reaffirm the safety and the advantages offered by Bt-crops. The U.S. National Academy of Sciences’ National Research Council found that such crops had no greater potential for risk than plants modified through conventional breeding practices, and less potential impact on non-target species than crops protected with chemical insecticides (1). In a report released late in September, the U.S. Environmental Protection Agency (EPA) confirmed that growers, the public and the environment all derive significant benefits from the availability and use of Bt crops. According to the EPA report, the major benefits predicted for Bt crops prior to their initial registrations – increases in yield for Bt-corn, and reduced use of chemical insecticides in Bt-cotton and Bt-potatoes – have largely been realized. EPA estimates that direct benefits to U.S. growers of the three biotech enhanced crops probably exceeded $100 million in 1999 (2).

But the safety and benefits of the technology may not be immediately apparent to the larger consumer public. Scientific reports rarely make headlines, and media personnel continue to give well-established opponents of genetic engineering a forum for their alarmist messages, however scientifically unsound or erroneous those arguments have proven to be.

As a result, public confidence in biotechnology is still tenuous. Consumer polls report widely varying results (often depending on the affiliation of the pollsters). In a study conducted this summer, consumers, given full disclosure of production methods, chose genetically engineered vegetables over their conventional counterparts by a significant margin, preferring the manipulation of crop varieties over the use of pesticides, but researchers make no claim to the general applicability of their results.

What is certain is that a serious error could have a devastating impact on public confidence in the technology. The recent incident in which a variety of corn unapproved for human consumption made its way into taco products in the U.S. underlines the need for rigid controls and established infrastructures to allow for the strict segregation of specialty products.

This need is likely to increase, with projects already underway such as the one at the University of Guelph, in which researchers are producing plant-derived antibodies in transgenic tobacco and potato plants. Biotechnology may well open up new markets for agricultural specialty products; we must be able to prove our ability to manage these products responsibly, however, if we are to maximize the benefits and minimize the risks the technology offers.

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