🚀 go-pugleaf

Jim Webster wrote:
> 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!

Only vegetarians can hear plants scream.