Brussels, 06 February 2002
A representative of the UK government agency English Nature has called on the European Commission to 'think twice' before authorising the use of genetically modified (GM) oilseed rape crops in the EU, following a study which shows that they can lead to the development of nuisance weeds.
A study on GM herbicide-tolerant oilseed rape crops in Canada, commissioned by English Nature, has revealed that the planting of these crops can lead to a process called 'gene stacking,' where genes from separate GM varieties accumulate in plants that grow from seed spilled at harvest (volunteer plants). This can result in cross-pollination between the different varieties of crop and the creation of plants with accumulated genetic traits from different GM varieties.
The Canadian study has revealed that plants created through 'gene stacking' are now resistant to several widely-used herbicides, with farmers regularly resorting to older herbicides to control them. The problem is exacerbated in Canada by the breakdown of the voluntary system of crop separation, which has lead to increased rates of cross-pollination between GM varieties.
Dr Brian Johnson, English Nature's biotechnology advisor, told CORDIS News that the report 'argues rightly that its inevitable we would see this kind of gene stacking in Europe' if GM oilseed rape crops like the ones studied in Canada were introduced in the EU.
Dr Johnson urged those responsible for GM regulation to 'think very carefully' before releasing this type of oilseed rape in the EU. 'We do not yet know how 'stacked gene' plants would behave either in farmers' fields or in the wild. The European regulatory system has not yet approved GM herbicide tolerant oilseeds for general release,' he said. English Nature will work 'to ensure the risks from possible gene stacking are properly addressed, and that we avoid the mistakes that have been made in Canada,' he added.
Dr Johnson said that he is concerned that 'gene stacking' oilseed rape could be introduced in the EU without a full understanding of its possible effects if the current de facto moratorium on authorisations of new GM products is lifted. He highlighted in particular glyphosate-tolerant GM oilseed rape, such as US company Monsanto's brand of Roundup Ready oilseed rape, saying that the introduction of the brand would 'inevitably...lead to multiple herbicide tolerance.'
English Nature also expressed concern at the European Commission's proposal to allow a threshold of up to 0.7 per cent GM seed in batches of conventional crop seed. Dr Johnson told CORDIS News it would be 'almost impossible to police these thresholds,' explaining that a one per cent GM contamination in a field could be equivalent to thousands of plants. He added that if there this one per cent contains several GM varieties then you end with up with several GM strains in one field, 'all of which are freely exchanging genes.'
Dr Johnson called on the Commission to 'hold back on making a decision on this proposal' until research into gene stacking and herbicide tolerance in oilseed rape currently being carried out in France and the UK 'is completed and understood.' During this research, he explained, different GM varieties of oilseed rape are deliberately planted close to one another, and results so far show this can lead to the development of multiple herbicide tolerance in the species.
English Nature is concerned that attempts to eliminate crop strains with multiple herbicide tolerance could lead to more intensive herbicide use in field margins and uncropped habitats, which act as important refuges for wildlife. He said that 'a lot of wildlife in Europe lives in the margins of fields' and it would be ironic if the Commission and the UK government, both of whom are trying to cut down on the use of chemicals in agriculture, created a need for the use of more herbicides 'by accident.'
For further information on English Nature, please consult the following web address:
For further information on the results of EC-funded research on GMOs (genetically modified organisms), please consult the following web address: