Genetic Engineering Has Failed to Significantly Boost US Crop Yields Despite Biotech Industry Claims, New Report Finds

For years, the biotechnology industry has trumpeted that it will feed
the world, promising that its genetically engineered crops will produce
higher yields.

That
promise has proven to be empty, according to a new report by the Union
of Concerned Scientists (UCS). Despite 20 years of research and 13
years of commercialization, genetic engineering has failed to
significantly increase U.S. crop yields.

"The
biotech industry has spent billions on research and public relations
hype, but genetically engineered food and feed crops haven't enabled
American farmers to grow significantly more crops per acre of land,"
said Doug Gurian-Sherman, a biologist in the UCS Food and Environment
Program and author of the report. "In comparison, traditional breeding
continues to deliver better results."

The
report, "Failure to Yield: Evaluating the Performance of Genetically
Engineered Crops," is the first to closely evaluate the overall effect
genetic engineering has had on crop yields in relation to other
agricultural technologies. It reviewed two dozen academic studies of
corn and soybeans, the two primary genetically engineered food and feed
crops grown in the United States.
Based on those studies, the UCS report concluded that genetically
engineering herbicide-tolerant soybeans and herbicide-tolerant corn has
not increased yields. Insect-resistant corn, meanwhile, has improved
yields only marginally. The increase in yields for both crops over the
last 13 years, the report found, was largely due to traditional
breeding or improvements in agricultural practices. (For the report, go
here.)

The UCS report comes at a time when food
price spikes and localized shortages worldwide have prompted calls to
boost agricultural productivity, or yield -- the amount of a crop
produced per unit of land over a specified amount of time.
Biotechnology companies maintain that genetic engineering is essential
to meeting this goal. Monsanto, for example, is currently running an
advertising campaign warning of an exploding world population and
claiming that its "advanced seeds . significantly increase crop
yields.." (For a pdf of the ad, go here.)
The UCS report debunks that claim, concluding that genetic engineering
is unlikely to play a significant role in increasing food production in
the foreseeable future.

The
biotechnology industry has been promising better yields since the
mid-1990s, but "Failure to Yield" documents that the industry has been
carrying out gene field trials to increase yields for 20 years without
significant results.

"After
more than 3,000 field trials, only two types of engineered genes are in
widespread use, and they haven't helped raise the ceiling on potential
yields," said Margaret Mellon, a microbiologist and director of UCS's
Food and Environment Program. "This record does not inspire confidence
in the future of the technology."

"Failure
to Yield" makes a critical distinction between potential -- or
intrinsic -- yield and operational yield, concepts that are often
conflated by the industry and misunderstood by others. Intrinsic yield
refers to a crop's ultimate production potential under the best
possible conditions. Operational yield refers to production levels
after losses due to pests, drought and other environmental factors.

The
study reviewed the intrinsic and operational yield achievements of the
three most common genetically altered food and feed crops in the United States: herbicide-tolerant soybeans, herbicide-tolerant corn and insect-resistant corn (known as Bt corn, after the bacterium Bacillus thuringiensis, whose genes enable the corn to resist several kinds of insects).

Herbicide-tolerant soybeans, herbicide-tolerant corn and Bt
corn have failed to increase intrinsic yields, the report found.
Herbicide-tolerant soybeans and herbicide-tolerant corn also have
failed to increase operational yields, compared with conventional
methods.

Meanwhile, the report found that Bt corn likely provides a marginal operational yield advantage of 3 to 4 percent over typical conventional practices. Since Bt
corn became commercially available in 1996, its yield advantage
averages out to a 0.2 to 0.3 percent yield increase per year. To put
that figure in context, overall U.S.
corn yields over the last several decades have annually averaged an
increase of approximately 1 percent, which is considerably more than
what Bt traits have provided.

In
addition to evaluating genetic engineering's record, "Failure to Yield"
considers the technology's potential role in increasing food production
over the next few decades. The report does not discount the possibility
of genetic engineering eventually contributing to increase crop yields.
It does, however, suggest that it makes little sense to support genetic
engineering at the expense of technologies that have proven to substantially increase yields, especially in many developing countries.
In addition, recent studies have shown that organic and similar farming
methods that minimize the use of pesticides and synthetic fertilizers
can more than double crop yields at little cost to poor farmers in such
developing regions as Sub-Saharan Africa.

The
report recommends that the U.S. Department of Agriculture, state
agricultural agencies, and universities increase research and
development for proven approaches to boost crop yields. Those
approaches should include modern conventional plant breeding methods,
sustainable and organic farming, and other sophisticated farming
practices that do not require farmers to pay significant upfront costs.
The report also recommends that U.S. food aid organizations make these more promising and affordable alternatives available to farmers in developing countries.

"If
we are going to make headway in combating hunger due to overpopulation
and climate change, we will need to increase crop yields," said
Gurian-Sherman. "Traditional breeding outperforms genetic engineering
hands down."