BioWorld International Correspondent
LONDON - The prospects for commercial growing of genetically modified crops in the UK receded yet further last week when the results of trials of winter oilseed rape were published showing there were fewer butterflies and bees in the GM fields compared to fields planted with conventional varieties.
Winter oilseed rape was the fourth and final crop tested in the UK government's farm-scale evaluations of herbicide-tolerant GM crops.
There was the same overall number of weeds in the GM and traditional varieties of winter oilseed rape, but there were fewer broad-leaved weeds - whose flowers and seeds provide food for insects, birds and small mammals - in the GM crop.
The differences, assessed at 65 sites across the country, were not the result of the genetic modification, but of the use of broader-spectrum herbicides on the GM crops.
But less herbicide was used on the GM crops and Tony Combes, deputy chairman of the Agricultural Biotechnology Council, the industry body representing the GM seed companies, said the trials, as a whole, show GM crops offer a better, more flexible weed management option, and that the differences between the impact of growing GM or non-GM crops on biodiversity is minimal.
"These results confirm once again that GM crops give farmers the flexibility they need to balance economic viability with environmental responsibility," he said.
The results now will be considered by the UK government's advisory group on GM crops, the Advisory Committee on Releases to the Environment.
Results for the three other crops - spring-sown oilseed rape, beet and forage maize - published in October 2003, showed conventional oilseed rape and beet were better for many groups of wildlife, while GM maize was better than conventional maize.
The GM maize results were called into question subsequently, because atrazine, the weed killer used on the conventional crop, was about to be banned by the European Union.
In March 2004, the UK government gave the go-ahead for the GM maize, Chardon LL, developed by Bayer CropScience, to be grown in the UK, but said it would contest the approval of GM beet and GM spring oilseed rape by the EU. However, it attached a condition to the GM maize approval, saying seed companies would have to fund a scheme to compensate non-GM farmers if their produce was contaminated with GM material. Three weeks later, Bayer CropScience withdrew its application for a license. There currently are no applications for licenses on the three other GM crops that were tested.
The publication of the results for winter oilseed rape was the last act in a series of initiatives dating back to 1999, which were designed to sway public opinion in favor of GM crops. In addition to the farm-scale trials, which were the largest trials of GM crops ever mounted, the government also funded a massive public consultation exercise involving more than 600 meetings, a cost-benefit assessment and a review of 600 scientific papers.
While the review concluded there was no evidence that eating GM crops posed any threat to human health, the cost-benefit analysis said weak consumer demand meant the current generation of GM crops was of little economic value to the UK. Meanwhile, it transpired that the assumption that if people were better informed about GM crops they would support the technology was wrong. In fact, attitudes hardened, and the more people found out, the more convinced they were that not enough is known about the long-term effects on human health.