J'espère que vous ne serez pas surpris mais le gouvernement canadien se prépare à autoriser les arbres OGM. Le GLOBE AND MAIL de Toronto a publié un article intéressant au sujet des arbres OGM. Les essais des arbres OGM se trouvent tous au Québec. Les essais sont effectués par le Service canadien des forêts du gouvernement canadien qui est basé à Québec. Aussi un article dans Le Soleil.
THE GLOBE AND MAIL
9 décembre 2006
O FrankentreeGenetically engineered spruce and poplars could save Canada's forests from over-harvesting and vicious pests such as the pine beetle. So why aren't environmentalists hugging these trees? SHARON OOSTHOEK reports SHARON OOSTHOEK
QUEBEC CITY -- When Christmas snows thaw this spring, Armand Seguin will cut down a stand of about 300 trees outside Quebec City. Although he spent years growing these spruce and poplars, he will take care to completely burn their trunks, branches, leaves and roots. And environmental groups such as Greenpeace can hardly wait for the chainsaws to rev up.
That's because these are Canada's first and only genetically modified trees to be grown outdoors. While some scientists believe that they represent the future of our forests -- and a forest-product industry that accounted for nearly 60 per cent of our $55.1-billion trade balance in 2005 -- others fear the fallout from experimenting with "frankenpines."
These environmentalists say trees with novel traits could spell the end of tree biodiversity and threaten the larger ecosystem. They point to scientific studies suggesting that animals developed abnormalities after being fed crops genetically engineered by biotech giant Monsanto. In short, they cannot fathom Mr. Seguin's argument that GM trees could be good for the environment.
Mr. Seguin works for the Canadian Forest Service, a federal government agency, and is one of the country's foremost experts in tree biotechnology.
In 1997, he planted poplars engineered to contain a gene from an E. coli bacterium. These acted as a marker to show whether the trees could be successfully genetically altered. He then followed that experiment in 2000 by planting spruce trees that were genetically engineered to contain DNA from the insecticide Bt (Bacillus thuringiensis), a bacterium used to control plant pests.
Mr. Seguin needed to know that when these genes were introduced, they would persist long enough to have the desired effect. But, now that he can confirm that genes were expressed throughout these trees' lives, they must be destroyed.
Still, Mr. Seguin has high hopes for his work going forward. One day, he sees plantations of trees with designer genes yielding more usable wood than they do now, removing incentive for logging old-growth forests. "I don't think we can continue to harvest the natural forest much longer," he says.
(In Mr. Seguin's home province of Quebec, the government's Coulombe Forest Commission made headlines two years ago when it denounced flawed calculations that led to over-harvesting. It recommended reducing the allowable cut by 20 per cent.)
But over-harvesting is not the only thing on Mr. Seguin's mind. He also hopes that by engineering trees that produce toxins against bugs, he can one day eliminate the need for pesticides.
"I like genetic engineering more than chemically sprayed trees," he says. "Those chemicals get in the water and stay around . . . my genetically engineered spruce Bt gene will degrade."
A robust but safe pesticide-generating tree certainly has implications for British Columbia, where the mountain pine beetle infected 8.7 million hectares of pine forest last year and continues to be one of the largest causes of economic loss in the province.
Says Mr. Seguin, a slim, energetic man who rides his bike to work: "These technologies have great potential for the environment. I understand there were some mistakes made in agriculture. But if we can start from zero again, I think we can present a positive aspect of GMOs [genetically modified organisms]."
Panos Grames, a forest researcher at the Vancouver-based David Suzuki Foundation, remains skeptical. He doubts that it will ever be possible to engineer a pesticide-producing tree that could prove harmless to either other trees or to the larger ecosystems they inhabit.
"The science is very experimental," he says. "With fewer insects, there are fewer birds. And insects break down organic matter for the ecosystem."
Even if the toxin a tree produces were targeted to just one insect, Mr. Grames adds, nature abhors a vacuum and another bug will inevitably come along to fill the void. "There may be a short-term gain, but there are long-term consequences every time you try to improve on Mother Nature," he says.
Speaking on the phone from his Montreal office, Greenpeace Canada's Eric Darier has concerns about Mr. Seguin's strategy as well. He argues that we know so little about how genetically modified organisms behave -- including GM trees grown in controlled test plots -- that we can't predict their impact should they find their way into natural forests.
"It's one thing to know what one gene can do. What we really don't know is the interaction between all these genes," he warns. Tree pollen can travel long distances and there are limited options for locating plantations. "Where are they going to plant these trees? On the Prairies? I don't think so. It's going to be in old clear-cut areas,
next to old-growth forest."
Mr. Seguin freely admits that it will never be possible to guarantee that GM trees won't cross-pollinate. Instead, he advocates creating genes that will not harm natural forests.
University of Toronto's Malcolm Campbell says the work Mr. Seguin and others are doing is crucial, that the cost of dismissing genetic engineering is too high. Climate change means trees are fighting off threats for which they have few defences -- pests and diseases more typical of warmer regions, drought, floods and extreme temperatures.
"We simply cannot afford to be throwing options out," says the molecular geneticist, part of an international team of scientists who announced in September that they had decoded the genome of the black cottonwood poplar -- a first for a forest tree.
"We have to decide what level of risk is acceptable [in genetic engineering]. For most environmentalists, no risk is acceptable. I can't accept that. It's the kind of thinking that would outlaw the use of the wheel."
China seems to agree. In 2002, the government there approved commercial plantations of poplars genetically engineered with the Bt bacterium. About 1.5 million trees have already been planted.
Meanwhile, big forestry companies in Canada see genetically engineered trees as a tool whose time has not yet come. Seth Kursman, the spokesman for Abitibi-Consolidated, says his company's emphasis is on natural generation. And scientists predict commercial planting in this country is still decades away.
As for environmentalists such as Mr. Darier? They recommend that Canada manage supply rather than try to keep up with demand for wood products. "We're being greedy in the short term and not thinking about the medium and long term," he says. "A shortage of a commodity is a good thing. It can encourage conservation. I think we're tackling the issue the wrong way."
Toronto-based Sharon Oosthoek writes on the environment.