GM crops created superweed, say scientists
Modified rape crosses with wild plant to create tough
pesticide-resistant strain
Paul Brown, environment correspondent
Monday July 25, 2005
The Guardian

http://www.guardian.co.uk/gmdebate/S...535428,00.html

Modified genes from crops in a GM crop trial have transferred into
local wild plants, creating a form of herbicide-resistant
"superweed", the Guardian can reveal.

The cross-fertilisation between GM oilseed rape, a brassica, and a
distantly related plant, charlock, had been discounted as virtually
impossible by scientists with the environment department. It was
found during a follow up to the government's three-year trials of GM
crops which ended two years ago.

The new form of charlock was growing among many others in a field
which had been used to grow GM rape. When scientists treated it with
lethal herbicide it showed no ill-effects.

Unlike the results of the original trials, which were the subject of
large-scale press briefings from scientists, the discovery of hybrid
plants that could cause a serious problem to farmers has not been
announced.

The scientists also collected seeds from other weeds in the oilseed
rape field and grew them in the laboratory. They found that two -
both wild turnips - were herbicide resistant.

The five scientists from the Centre for Ecology and Hydrology, the
government research station at Winfrith in Dorset, placed their
findings on the department's website last week.

A reviewer of the paper has appended to its front page: "The
frequency of such an event [the cross-fertilisation of charlock] in
the field is likely to be very low, as highlighted by the fact it has
never been detected in numerous previous assessments."

However, he adds: "This unusual occurrence merits further study in
order to adequately assess any potential risk of gene transfer."

Brian Johnson, an ecological geneticist and member of the
government's specialist scientific group which assessed the farm
trials, has no doubt of the significance. "You only need one event in
several million. As soon as it has taken place the new plant has a
huge selective advantage. That plant will multiply rapidly."

Dr Johnson, who is head of the biotechnology advisory unit and head
of the land management technologies group at English Nature, the
government nature advisers, said: "Unlike the researchers I am not
surprised by this. If you apply herbicide to plants which is lethal,
eventually a resistant survivor will turn up."

The glufosinate-ammonium herbicide used in this case put "huge
selective pressure likely to cause rapid evolution of resistance".

To assess the potential of herbicide-resistant weeds as a danger to
crops, a French researcher placed a single triazine-resistant weed,
known as fat hen, in maize fields where atrazine was being used to
control weeds. After four years the plants had multiplied to an
average of 103,000 plants, Dr Johnson said.

What is not clear in the English case is whether the charlock was
fertile. Scientists collected eight seeds from the plant but they
failed to germinate them and concluded the plant was "not viable".

But Dr Johnson points out that the plant was very large and produced
many flowers.

He said: "There is every reason to suppose that the GM trait could be
in the plant's pollen and thus be carried to other charlock in the
neighbourhood, spreading the GM genes in that way. This is after all
how the cross-fertilisation between the rape and charlock must have
occurred in the first place."

Since charlock seeds can remain in the soil for 20 to 30 years before
they germinate, once GM plants have produced seeds it would be almost
impossible to eliminate them.

Although the government has never conceded that gene transfer was a
problem, it was fear of this that led the French and Greek
governments to seek to ban GM rape.

Emily Diamond, a Friends of the Earth GM researcher, said: "I was
shocked when I saw this paper. This is what we were reassured could
not happen - and yet now it has happened the finding has been hidden
away. This is exactly what the French and Greeks were afraid of when
they opposed the introduction of GM rape."

The findings will now have to be assessed by the government's
Advisory Committee on Releases to the Environment (Acre). The
question is whether it is safe to release GM crops into the UK
environment when there are wild relatives that might become
superweeds and pose a serious threat to farm productivity. This has
already occurred in Canada.

The discovery that herbicide-resistant genes have transferred to farm
weeds from GM crops is the second blow to the hopes of bio-tech
companies to introduce their crops into Britain. Following farm scale
trials there was already scientific evidence that herbicide-tolerant
oilseed rape and GM sugar beet were bad for biodiversity because the
herbicide used to kill the weeds around the crops wiped out more
wildlife than with conventionally grown crops. Now this new research,
a follow-up on the original trials, shows that a second undesirable
potential result is a race of superweeds.

The findings mirror the Canadian experience with GM crops, which has
seen farmers and the environment plagued with severe problems.

Farmers the world over are always troubled by what they call
"volunteers" - crop plants which grow from seeds spilled from the
previous harvest, of which oilseed rape is probably the greatest
offender, Anyone familiar with the British countryside, or even the
verges of motorways, will recognise thousands of oilseed rape plants
growing uninvited amid crops of wheat or barley, and in great swaths
by the roadside where the "small greasy ballbearings" of seeds have
spilled from lorries.

Farmers in Canada soon found that these volunteers were resistant to
at least one herbicide, and became impossible to kill with two or
three applications of different weedkillers after a succession of
various GM crops were grown.

The new plants were dubbed superweeds because they proved resistant
to three herbicides while the crops they were growing among had been
genetically engineered to be resistant to only one.

To stop their farm crops being overwhelmed with superweeds, farmers
had to resort to using older, much stronger varieties of "dirty"
herbicide long since outlawed as seriously damaging to biodiversity.

Q&A: What the discovery means for UK farmers

What's the GM situation in the UK?

No GM crops are currently grown commercially in the UK. Companies who
wish to introduce them face a series of licensing hurdles in Britain
and Europe and interest has waned in recent years amid public
opposition.

Other firms have dropped applications in the wake of the government
field scale trials that showed growing two GM varieties - oilseed
rape and sugar beet - was bad for biodiversity.

The EU has approved several GM varieties and the UK government
insists that applications will be considered on a case-by-case basis.

Where are GM crops grown?

Extensively in the wide open spaces of the US, Canada and Argentina.
In Europe, Portugal, France and Germany have all dabbled with GM
insect-resistant maize. Spain plants about 100,000 hectares (250,000
acres) of it each year for animal feed.

What is a superweed?

Many GM crop varieties are given genes that allow them to resist a
specific herbicide, which farmers can then apply to kill the weeds
while allowing the GM crop to thrive.

Environmental campaigners have long feared that if pollen from the GM
crop fertilised a related weed, it could transfer the resistance and
create a superweed. This "gene transfer" is what appears to have
happened at the field scale trial site. It raises the prospect of
farmers who grow some GM crops being forced to use stronger
herbicides on their fields to deal with the upstart weeds.

Is it a big problem?

Not yet. Farmers in the UK do not grow GM crops commercially. If they
did, then the scale of possible superweed contamination depends on
two things: whether the hybrid superweed can reproduce (many hybrids
are sterile) and, if it could, how well its offspring could compete
with other plants. Herbicide-resistant weeds could potentially grow
very well in agricultural fields where the relevant herbicide is
applied. Most experts say superweeds would be unlikely to sweep
across the UK countryside as, without the herbicide being used to
kill their competitors, their GM status offers no advantage.

Some GM crops, such as maize, have no wild relatives in the UK,
making gene transfer and the creation of a superweed from them
impossible.

Is it a surprise?

On one level no, gene flow and hybridisation are as old as plants
themselves. Short of creating sterile male plants, it's simply
impossible to stop crops releasing pollen to fertilise related
neighbours. But government scientists had thought that GM oilseed
rape and charlock were too distantly related for it to occur.

The dangers of hybridisation where it does happen are well documented
- experts from the Dorset centre behind the latest research published
a high-profile paper in 2003 in the US journal Science showing
widespread gene flow from non-GM oilseed rape to wild flowers.

Have superweeds surfaced elsewhere?

Farmers in Canada and Argentina growing GM soya beans have large
problems with herbicide-resistant weeds, though these have arisen
through natural selection and not gene flow through hybridisation.
Experiments in Germany have shown sugar beets genetically modified to
resist one herbicide accidentally acquired the genes to resist
another - so called "gene stacking", which has also been observed in
oilseed rape grown in Canada.

"Beach Runner" > wrote in message
. ..
> GM crops created superweed, say scientists
> Modified rape crosses with wild plant to create tough
> pesticide-resistant strain
As an ex-chemical engineer that worked for Monsanto and Polaroid giving
everyone cancer for a living before I turned into a health nut, I say: If
you liked chemical pollution, you will LOVE genetic pollution.
Why? Chemicals do not reproduce, change their genetic code and
reproduce again: that is evolution. GMO's will interfere with evolution
itself, it already has, and may lead to much wider and more severe disasters
than chemical pollution ever could.
What if, say, the bacteria that they use to "eat" the carbon-carbon
bonds in petroleum spills mutates, over several million generations, to
"eat" the carbon-carbon bonds in plant material, and it comes ashore??
They are tinkering around with Life itself, with near total ignorance,
and look what they did with simple chemicals and petroleum, with near total
ignorance.
There is NO rational scientific or ethical oversight in current
biological/genetic research, or science in general, just as there was none
for the entire history of the Industrial Revolution.
The force driving genetic research is "Can we do it; and how do we make
a buck out of it?"
Economics, noBalls, will destroy the planet, and people of your
psychopathic mentality are the harbingers.

Laurie