The Union of Concerned Scientists (UCS) on June 16 relayed an +action alert
to organic farmers regarding the pending EPA approval of genetically
engineered corn and cotton containing B.t. genes for insect control. The
document falsely represented the activities of seed companies in developing
these crops. The following message serves to present the facts regarding
B.t. crops from the perspective of Mycogen Plant Sciences, which is
developing B.t. corn. Mycogen believes that B.t. corn can be a valuable
resource to organic and sustainable agriculture farmers.
B.t. is currently sprayed on corn to control several pests, including the
European Corn Borer (ECB), which is the target pest for corn that is
genetically engineered to express a B.t. toxin. B.t. sprays have
conventionally been applied at a rate of up to 100 grams of toxin per acre.
B.t. toxin in corn is expressed in vivo at a rate of about 5 grams per acre,
specifically in plant tissues that are affected by the pest. This
significant reduction in use rates clearly aids organic farmers. If the UCS
accurately presented the facts, it could not justify the accusation that the
EPA approval of B.t. crops will serve to +squander B.t. as a natural
The +widespread adoption of B.t. crops mentioned by the UCS, particularly
with regard to corn engineered for ECB control, cannot reasonably be expected
to occur. Mycogen and Ciba Seeds, our partner in B.t. corn development,
together produce about 5% of the seed corn in the U.S. Additionally, an
individual farmer will not typically plant all acreage to one particular
hybrid; more than ample acreage of non-B.t. corn will exist in the
foreseeable future to prevent the alleged +widespread adoption of B.t. crops.
It is expected that the development of resistance by insects can be avoided
by the deployment of an effective and comprehensive resistance management
strategy, using the best available scientific information. Companies
developing and marketing transgenic crops expressing B.t. proteins have a
vested interest in maintaining the utility and added value of these seeds.
Organic farmers and industry have the same goal: preserving the utility of
these highly specific pesticidal proteins for as long as possible. Mycogen
Plant Sciences has worked with Ciba Seeds to develop a multi-faceted
resistance management strategy. Our strategy employs the following
Maintain substantial refugia for susceptible insects with a combination of
market forces and grower practices. This approach is the cornerstone of our
strategy, allowing wild-type sensitive pest insects to interbreed with the
rare resistant individuals to reduce selection pressure and genetically
+dilute out resistance genes in a population.
High dosage toxin gene expression that eliminates heterozygous pest
Monitor pest insect populations in areas where transgenic crops are planted.
Deploy native-resistant plants to provide multiple, independent mechanisms
of control, significantly reducing the chance for resistance development.
Develop alternative B.t.-derived proteins for future deployment that are
effective on insects resistant to existing toxins.
Continually refine resistance management strategies by consulting with
leading academic researchers expert in this area.
Resistance management is not a matter of enforcement as suggested by the UCS;
rather it is a matter of cooperation between the seed industry, farmers and
researchers to maintain the long-term availability of this resource as a pest
control tool for organic, sustainable, and conventional farming.
B.t. crops are a valuable tool to achieve significant reductions in the use
of synthetic chemical pesticides. While the UCS contends that some
scientists predict that resistance to B.t. crops could develop within just a
few growing seasons, they fail to acknowledge that scientists on EPA's
Pesticide Resistance Management Workgroup have stated publicly that
appropriate resistance management practices can be developed for these
products that will prevent or delay the development of resistance while
maintaining the value of B.t. crops as alternatives to synthetic chemical
EPA approval of B.t. crops and their subsequent commercialization will not be
a disadvantage to organic farmers. It is incorrect to think that EPA would
approve the deployment of these crops prior to the demonstration by seed
companies that effective resistance management strategies are in place. Such
strategies for B.t. corn are in the hands of EPA. USDA has already reviewed
B.t. corn; a Determination of Nonregulated Status was issued in April.
Organic farmers will profit by the pending EPA approval of B.t. corn, as it
will actually preserve B.t. as a natural resource. If you have questions
about B.t. corn, please write to the Regulatory and Environmental Affairs
Department, Mycogen Corporation, 5501 Oberlin Drive, San Diego, CA 92121 or
phone 619-453-8030 x423.