🚀 go-pugleaf

On Sat, 09 Jun 2007 10:53:45 -0400, ah <splifingate@gmail.com> wrote:

>Aunt Sally wrote:
>> On Mon, 25 Jul 2005 23:01:50 +0200, marcus@myrealbox.com wrote:
>> 
>>>		
>>>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
>>>
>>>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.
>>>
>>>Article continues
>>>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.
>>>
>>>� David Adam
>>>
>>>http://www.guardian.co.uk/gmdebate/Story/0,2763,1535428,00.html
>>>
>> 
>> Go organic, go veggie. Safest all round by far.
>
>Lies!

True!