Biotech Trees Rooted in Controversy; Engineering a Better
Poplar has Advocates and Critics
12/20/99
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RELAYED TEXT STARTS HERE:
Title: Biotech trees rooted in controversy; Engineering a better
poplar has advocates and critics
Source: Newhouse News Service
Status: Copyright 1999, contact source for permission to reprint
Date: December 20, 1999
Byline: Patrick O'Neill
CORVALLIS, Ore., Dec. 20 - The delicate plants sprouting in glass
dishes are little spots of greenery about the size of erasers. They
are coddled by scientists in a room filled with artificial light,
where the temperature is always 77 degrees. Steven Strauss hopes that
one day these dabs of plant life, taking root in a gelatinous
solution of nutrients and growth hormones, will become 30-foot-tall
poplar trees, genetically engineered to resist beetles and even the
most potent weed spray.
THE NEXT generation of the trees, which already grow faster than most
other kinds of trees, might even be shorter and bulkier, reprogrammed
to use their energy to grow wide instead of tall. Eventually, Strauss
hopes, thousands of acres of the genetically altered poplars would be
grown in neat rows like corn, becoming a super-efficient manufacturer
of plant fiber. The domesticated poplars may even become more
attractive to the forest products companies than regular trees.
"What we're doing is domesticating the organism so it produces what
people want," said Strauss, a professor of genetics and molecular
biology at Oregon State University.
THE OTHER SIDE
But where Strauss sees efficiency and a way to save forests, the
World Wildlife Fund and other environmental groups see a threat to
the habitats of creatures who live in and around the trees and to the
diversity of plant life.
Several environmental organizations - including at least one
Washington group that vandalized a test crop of genetically altered
poplars last month - worry about whether the technology might create
bugs resistant to insecticides manufactured in genetically engineered
trees. Too little is known about the long-term effects of subtle
changes in these altered trees, critics say.
"Without adequate safety testing, we don't know what the impact will
be on the ecology," said Charles Margulis, a spokesman for Greenpeace
U.S.A.
ABOUT THE SCIENCE
The key to Strauss' work, and that of all genetic engineers, is
altering a complex molecule called deoxyribonucleic acid, or DNA.
Genes, which carry the instructions that tell all living cells how to
become plants and animals, are segments of the molecular code inside
strands of DNA.
During the past decade, advances in computer technology and molecular
biology have brought an avalanche of knowledge about ways to
manipulate DNA. The challenge for researchers such as Strauss is to
figure out how to switch genes on or off, or add new genes from other
organisms, in such a way that the plant develops new traits.
Sometimes a new trait - such as resistance to insects - can be
achieved with the addition of a single gene. Other traits - such as
fast growth - require more genes, making the task vastly more
difficult.
One of the two genes that Strauss inserted in the poplars is from the
Bacillus thuringiensis bacterium, which produces a protein that is
deadly to certain kinds of insects, including poplar-eating beetles.
The second gene, from a strain of the single-celled Agrobacterium,
neutralizes the effects of glyphosate, the plant-killing ingredient
in the commercial product Roundup. If the crops are immune to the
effects of glyphosate, growers can spray an entire field and only the
weeds will die.
MONSANTO'S CUT
The two genes that Strauss is using were discovered by the Monsanto
Corp., which has used the technology to produce corn, soybean and
other crops that are resistant to insects and Roundup. Strauss
acquired the genes under a research agreement with Monsanto. If the
engineered poplars go into commercial production, Monsanto will
receive revenue from their use.
The fiber-hungry forest products industry is eyeing the poplar
project as a possible source of paper and wood. The U.S. Department
of Energy sees poplars as a potential source of fuel.
The versatile tree also acts as a kind of environmental sponge, using
its roots to absorb heavy metal pollution and converting it into
harmless substances.
CLONING, NO SEEDS
Poplars are relatively easy plants to modify. Because each cell has
the ability to grow into a tree, researchers don't have to produce
seeds to grow a poplar. They can simply clone them by chopping up one
tree and, in effect, planting the pieces.
To start the process, Strauss and his technicians cut young poplar
trees into small pieces and soak them for two days in a solution of
Agrobacterium. The bacterium has been genetically engineered to carry
genes for herbicide tolerance and insect resistance. Also included
are genes that enable the plant cells to withstand the effects of an
antibiotic.
As the pieces of poplar soak, the Agrobacterium acts as a kind of
Trojan horse to smuggle the foreign genes into the poplar's genetic
structure. The pieces of poplar are then put into petri dishes filled
with a jellylike plant food, hormones to promote root growth and an
antibiotic.
If the gene transfer is successful - it works in 5 percent to 10
percent of the poplar pieces - the plants will be protected from the
antibiotic and develop leaves and roots. If the transfer doesn't
work, the antibiotic does not let the plant develop.
The growing pieces of poplar are then transplanted and will,
eventually, grow into genetically altered trees.
TEST FARM
Boise Cascade provides some test plots for the modified trees on its
tree farm in eastern Oregon. The Boise company grows 18,000 acres of
regular poplars there and uses the fiber in its paper plant in
Wallula, Wash.
"It's striking," said Chuck Wierman, the company's farm manager. "You
can walk down the row and actually pick out which ones have been
modified with the gene. They haven't been defoliated by the insect."
From Strauss' perspective, bug- and herbicide-resistant poplars are
just the beginning.
Nature designed poplars to grow tall and slender, reaching
frantically for the sky, seeking life-giving sunlight. In the wild,
those traits are vital for the tree's survival.
But for plantation-grown poplars, they're a waste of energy. Strauss
would like to eliminate poplars' wasteful tendencies by making them
concentrate their efforts on producing wood. But those efforts will
require more research.
FLOWERLESS POPLAR?
Another area being researched is a way to eliminate flowers on
poplars. Such trees would grow faster because they would not spend
energy on reproduction, and they would cause fewer allergic reactions
because they wouldn't produce pollen or cottony seeds.
Eliminating flowers would also shortcut one of the critics'
objections to genetically engineered trees - that engineered genes
could escape into the wild tree varieties, with unknowable
consequences. A flowerless poplar would produce no pollen, leaving no
way for modified genes to escape.
"Unless you have flowering control, it might be difficult to go
forward with this commercially," Strauss said.
ALL THOSE AGAINST
Not everyone shares Strauss' vision of a genetically engineered
future.
On Nov. 9, the World Wildlife Fund called for a global moratorium
against the commercial release of genetically modified trees, pending
more safety studies. The WWF wants assurances that genes from
modified trees won't escape into other plants, producing "super
weeds," among other things.
A group called Washington Tree Improvement Association also opposes
what it believes are the unforeseen hazards of bioengineered trees.
It claimed responsibility for vandalizing genetically engineered
poplars in a Washington State University research area in Seattle on
Nov. 26, as part of protests against the World Trade Organization.
Environmentalist groups also have voiced concern about similar
genetic alterations in food crops, particularly in corn and soybeans.
Opposition to genetically altered foods has rooted itself firmly in
Europe during the past several years, and in the past six months a
chorus of protest has risen in the United States.
FDA'S ROLE
In response to growing public concern, the U.S. Food and Drug
Administration, which oversees food derived from genetically
engineered sources, has been conducting hearings across the country
with an eye to changing its policies. Such uncertainties have cast a
chill over all plant genetic engineering, including that done by
Strauss.
This has put Strauss in an uncomfortable position. The researcher
considers himself an environmentalist. Raised in Brooklyn, N.Y.,
where forests are few and far between, Strauss developed a deep
interest in woodlands during long hikes in the Adirondack Mountains
in upstate New York.
But he worries about the future of funding for his project and those
like it. Right now, his research is being paid for by an organization
called the Tree Genetic Engineering Cooperative, which includes 20
companies - mostly from the forest products industry - and government
agencies, including the Department of Energy. Strauss says opponents
of genetic engineering are engaging in scare tactics and that they're
unable to show any instance in which genetically engineered plants
have harmed the environment.
"How do you find out if it's safe?" he said. "Sit down and model it
on a computer? You need to put the trees out to see if they're going
to fall over in the wind and see whether they'll be more susceptible
to pests."
Patrick O'Neill is a staff writer with The Oregonian of Portland,
Ore.