An open field trial with GM wheat in Harpenden near London can go ahead thanks to the police, who prevented a planned destruction of the trial on May 27. In the run-up to the protest action there was a broad public debate throughout the UK in which the scientists engaged proactively with the GM opponents. The protest group argued that the research project was unnecessary and would pose risks to the environment. The scientists explained in a video and blog and on Twitter that they are attempting to contribute to a more environmentally friendly form of agriculture. An online petition against the trial destruction received over 6,000 signatures.

On May 1, after the protest group Take the Flour Back had announced publicly that they intended to destroy the trial field at the Rothamsted Research Institute on May 27, they received a public video message. In the video, four of the scientists involved in the research explain their project, ask the protesters not to destroy the trial field and appeal to them to join the debate. The video appeal was published on the Sense about Science website together with the text of the message and an online petition against the trial destruction. A large number of newspapers reported the story and on May 22 representatives from both sides clashed on BBC Newsnight.

In order to facilitate a more in-depth discussion, the Rothamsted Research Institute invited the GM opponents to attend a public discussion at a neutral location on May 24. Take the Flour Back had originally suggested a public debate of this kind, but declined the invitation to attend the May 24 event shortly beforehand.

The research project: pest-resistant wheat

As part of publicly funded research, a mechanism used by some plants to protect themselves against aphids was transferred to wheat. A large proportion of conventionally grown wheat in Britain is currently treated with broad-spectrum insecticides to control aphids. The aphids suck sap from the plants and transmit viruses, so can cause considerable damage to crops. Repeated use of insecticides can lead to the pests developing resistance and can harm non-target organisms. Moreover, insecticides have to be applied using agricultural machinery, which uses energy.

The transgenic wheat carries a gene similar to one found in peppermint which contains information for a chemical alarm signal that deters aphids: the aphids move away as soon as they come into contact with the E-ß-farnesene. As well as deterring aphids, the substance also attracts their natural enemies, including ladybirds. In addition, the wheat carries a gene for an enzyme that produces the precursor molecule for E-ß-farnesene. This enzyme, farnesyl pyrophosphate synthase (FPPS), is present in almost all organisms, although there are species-specific differences in the gene sequence. Wheat naturally contains an FPPS gene, but the transgenic wheat variety has had an additional FPPS gene inserted so that it produces E-ß-farnesene more efficiently. The added FPPS gene is synthesised artificially. Its DNA sequence is closest to that found in cows.

It was this alleged “cow gene” that provided the inspiration for the logo used by the Take the Flour Back campaign: a loaf of bread with the legs and head of a cow. The idea that an animal gene had been added to wheat set lots of people against the research project.

Fear of cross-pollination

The debate: opportunities versus risks

The opponents’ main fear is cross-pollination. They claim this would be a problem not only because of the two inserted genes, but also because of the plant’s resistance to the herbicide glufosinate, which is conferred by a marker. If the plants were to outcross, wild grasses could develop glufosinate resistance. The trial’s opponents also believe it is conceivable that the pheromone could harm non-target organisms or that a change in the aphids’ behaviour and modification of the wheat plants’ make-up could lead to changes in the ecosystem.

The scientists responded to these concerns saying that the purpose of the current field trial is to investigate potential agroecological impacts. They claim that the risk of outcrossing is almost zero, since wheat is a self-pollinating plant. Nevertheless, a buffer strip of conventional wheat has been planted around the trial field and there is a fence to prevent plant material being carried off the field by animals.

Another of the protesters’ accusations is that the research project is unnecessary. The genetic modifications have been carried out on spring wheat, which is hardly grown in the UK and is not affected by aphids. They claim that experience with insecticide- and herbicide-resistant GM plants has generally shown that pests develop resistance, leading eventually to an increased use of chemicals. Organic farming is, they say, a better solution. The critics point out that the Rothamsted Research Institute itself trialled companion cropping recently. Companion cropping involves sowing plants alongside a crop that deter pests by emitting odours.

The scientists stress that spring wheat is just being used as a model plant in this instance and that the new genes can be transferred to winter wheat at a later date without any problem. They say that companion cropping is very labour-intensive and is mainly suitable for small subsistence farms, e.g. in Africa. It would be too costly, however, for Britain’s high-performance agricultural sector.

Finally, the critics question the scientists’ claim that the trial is purely for public research and is not intended for commercialisation or patent purposes. They cite the Rothamsted Research Institute’s numerous industrial partnerships. If the plants are in fact grown, they claim, they will have to be marketed commercially, and only large corporations would have the necessary resources.

Scientists seek publicity

It is partly thanks to the scientists’ proactive stance that there has been such an intense public debate about plant genetic engineering in Britain in recent weeks. The online petition against the crop destruction had received around 6000 signatures from a broad cross-section of society by May 27. However, because Take the Flour Back did not call off the planned destruction, the trial field was eventually given police protection. On May 27 around 400 GM opponents and about the same number of police officers turned up at the site. The demonstration in Rothamsted Park remained peaceful and lasted several hours. The following night, however, the institute’s website was down for several hours as the result of a cyber attack. Nevertheless, the open field trial can continue, and so can the debate about plant genetic engineering.