Friends of the Earth, July 25 2005

Government Study Finds UK's First GM 'Superweed'

New government research, revealed today (1), reports on the discovery of the first genetically modified (GM) superweed in the UK - the result of GM oilseed rape cross-breeding with a common weed in the farm scale evaluations (FSE). The exact location of the GM weed is not revealed, but it will have been on one of 23 former FSE sites tested in 12 counties (2). The revelation raises serious concerns about the impact of growing GM oilseed rape in the UK - and comes less than a month after the UK tried to persuade other European countries to lift their own bans on growing GM oilseed rape.

The government study monitored gene flow from Bayer's herbicide resistant GM oilseed rape to related wild plants during the government-sponsored farm scale evaluations (FSE) of GM crops. At one test site, the researchers found a GM version of the common weed charlock (Sinapis Arvensis) growing in the field the year after the GM trial. The plant was resistant to the weed killer used in the GM trial and was confirmed as containing the gene inserted into the GM oilseed rape. This is the first known case of such an occurrence in the UK, and overturns previous scientific assumptions that charlock was unlikely to cross-breed with GM oilseed rape (3).

Charlock is a common weed found alongside oilseed rape in the UK and mainland Europe. If GM oilseed rape were grown commercially, herbicide resistant weeds could become widespread. Farmers would then have to use more - and more damaging - weedkillers to get rid of them, with knock-on impacts on the environment. Bayer has lodged two applications for approval to grow GM oilseed rape with the European Commission. Approval would allow the GM oilseed to be grown in the UK.

Just last month the UK Environment Minister Elliot Morley voted to try and force France and Greece to lift their bans on GM oilseed rape (4). The bans were originally put in place in 1998 because of concerns about gene escape into the environment. Elliot Morley justified the UK position saying that he had to vote on the basis of the available science (5) whilst his department was holding research confirming the risk of gene escape from GM oilseed rape.

Friends of the Earth's GM Campaigner Emily Diamand said: "The Government's trials have already shown that growing GM crops can harm wildlife. Now we're seeing the real possibility of GM superweeds being created, with serious consequences for farmers and the environment.What is disturbing is the way the Government appears to have ignored its own evidence in trying to force GM crops onto countries that have a real cause for concern. The Government must stop acting as cheerleader for GM crops, and start paying attention to its own research, and above all, to the British public."

(2) 23 sites were included in the research, in Aberdeenshire, Dorset, East Riding of Yorkshire, Gloucestershire, Hertfordshire, Lincolnshire, Norfolk, Nottinghamshire, Oxfordshire, Shropshire, Warwickshire and Worcestershire. See for details of the trial locations. It is not clear at which site the GM charlock was found. See page 12 of the full report.
(3) Up until now it was assumed that it would be very difficult for charlock to cross breed with oilseed rape, and even if it did, the offspring would be unlikely to survive. In a review of the evidence by the European Environment Agency in 2000, it was concluded that "there appears to be general agreement that natural gene flow is not likely to occur between B. napus and S. arvensis." (Brasica napus is oilseed rape, Sinapis arvensis is Charlock)
(4) Despite the UK position, a majority of EU Environment ministers voted to allow countries to keep their national GM bans
Don't let Bush and the WTO win - Help stop the European Commission from backing down on GM foods (PDF†)
(5) Environment Minister Elliot Morley is quoted on Radio 4's Farming Today programme on 24 June as saying: "We'll vote on the basis of the scientific advice that we've received."
"And they are all saying that as there has been no new evidence brought forward to defend the argument for a blanket ban, there is no reason not to support the commission."
Mr Morley acknowledged there was widespread public opposition to GM crops which could not be ignored. "But on the other hand we cannot deviate from the scientific advice because otherwise we do leave ourselves open to pressure from commercial companies, for example, and we are not going to bow to that" he said.
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July 25, 2005, The Guardian

GM crops created superweed, say scientists

Modified rape crosses with wild plant to create tough pesticide-resistant strain

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. (Paul Brown)