- NEW YORK - Steve Love claims the best argument for using genetically engineered
crops is a beetle-infested potato field.
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- "I've stood in fields that are completely
brown because not only was there not a single leaf left, but the beetles
had even chewed the stems down," said Love, a potato breeder at the
University of Idaho. "It leaves the field's production at zero."
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- Rather than battling the Colorado potato
beetle with hazardous, chemical pesticides, Love and others say a farmer's
best defense is a "smarter" potato. By inserting genes from a
certain bacterium into the potato, researchers have created a crop whose
very DNA contains a defense against the insect.
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- But while Monsanto, Love's employer and
the corporate creator of the insect-resistant New Leaf potato, makes grand
claims for its genetically engineered food products, critics fear the genetic
tinkering could lead to disastrous implications in the agricultural world.
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- "It's not moral to go in and mess
about with genomes and then throw it out into nature without the slightest
idea of what you're doing," said Donella Meadows, an organic farmer
in New Hampshire and adjunct professor of environmental studies at Dartmouth
College.
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- So far, the rift between those who forecast
trouble from genetically engineered foods and those who hold it as agriculture's
salvation has been unbridgeable. Last week, talks to create a world treaty
regulating trade in genetically modified products broke down when the United
States and five other large agricultural exporters resisted claims that
genetically engineered corn and wheat pose enough of a danger to require
international monitoring.
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- What is so dangerous about a crop with
an extra gene? In the field of agriculture, there are two main worries:
superweeds and mutant bugs.
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- Plants reproduce by releasing pollen
- spores that contain the plant's complete genetic information. It is possible
for pollen from one plant to fertilize a plant of a different, but closely
related species. Scientists fear if this occurred between a genetically
engineered plant and a wild relative, the process could breed a fortified
weed.
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- "Many of the important domesticated
crops do not have wild relatives in the U.S. so it's not as much of a danger,"
explained Jane Rissler, a plant pathologist at the Union of Concerned Scientists.
"But in other parts of the world, the problem may be more severe."
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- Rissler refers to Mexico, where it is
common for pollen to flow between domesticated corn crops and a local wild
corn breed, teosinte. If a genetically engineered corn is introduced to
a Mexican farm, she argues, its pollen may cross with teosinte and produce
an unruly version of the wild corn.
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- Corbis The Colorado potato beetle has
proven to be a worthy adversary to farmers, by evolving resistance to pesticides
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- Another concern is a genetically engineered
crop could prove to be overly persistent, turn up in unwanted places in
years to come and become a weed itself.
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- Plants aren't the only organisms that
people fear could take on Frankenstein-like qualities. Once pests like
the Colorado potato beetle are exposed to a genetically engineered crop,
there is a possibility they could evolve to become super-resistant to a
farmer's arsenal of defenses.
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- For example, the gene that steels the
New Leaf potato against the Colorado potato beetle comes from a bacterium
called Bacillus thuringiensis, or Bt. Bt is now commonly used as an organic
pesticide, but its effectiveness only lasts as long as the Bt remains on
the leaves of potato plants - usually a few days. By inserting the Bt protein
directly into the potato plant, the protein - lethal only to the beetle
- is encased by the plant, root to shoot.
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- The problem is, if a beetle with a Bt-resistant
gene emerges, it will mate with other Bt-resistant beetles and perpetuate
subsequent generations of a Bt-hearty breed. This way, the beetle may
eventually develop a resistance to the Bt protein just as it has adapted
to survive repeated doses of chemical pesticides.
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- "Resistant insects will emerge,
there's no question about that," said Maarten Chrispeels, a biology
professor at the University of California in San Diego. "But that
will happen whenever you kill most of the pests."
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- Chrispeels argues the alternatives to
possibly losing Bt as an effective agricultural weapon are worse. Pesticides
pose toxic harm to the farmers who apply them and to the people consuming
the crops they're protecting. And while organic farmers like Meadows argue
that rotating crops and planting a mosaic of crops can beat the bug problem,
Chrispeels claims those methods just aren't economically viable.
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- "There aren't enough profitable
crops for farmers to introduce three or four crops in rotation," he
said.
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- The prospect of an emerging Bt-resistant
beetle is especially threatening to organic farmers since it is one of
the only natural pesticides that meets organic farming guidelines. That's
one reason why, on Feb. 18, organic farmers joined a coalition of environmentalists
and consumers to sue the Environmental Protection Agency over the issue
of Bt-engineered plants.
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- "Stealing is stealing is stealing,"
said Meadows. "They're taking a vital tool away from organic farmers."
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- From his potato laboratory in Idaho,
Love says he's sympathetic to such claims, but that he's more sympathetic
to farmers who stand to lose vast crop fields to infestation.
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- "Organic growers are almost a nonexistent
portion of our agricultural production," he said. "If we mind
our Ps and Qs, then the potential to benefit a huge segment of production
is probably worth the risk."
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- About 45 million acres of American farmland
have been planted with genetically engineered crops, most of it corn, soybeans,
cotton and potatoes. Discussions for a treaty on international trade of
genetically altered foods is expected to resume in May 2000. Chrispeels
believes these talks will be vital.
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- "We're going to need long-term tests
to determine what rules we need for specific kinds of genetically engineered
organisms," he said. "We have to remember this is not just economics,
it's science."
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