For researchers at the UK's Rothamsted research center, the past few weeks must have felt like a train wreck in slow motion. The team engineered a strain of wheat to carry an enzyme, found in many other plant species, that will produce an aphid-repelling chemical. After what was undoubtedly a lot of time in the lab spent preparing the wheat, the Rothamsted staff was finally ready to test whether their modified wheat actually did what it was supposed to in the field.

But starting in early April, they had reason to wonder whether they'd be able to learn anything from their test. In mid-April, a group calling itself 'Take the Flour Back' issued a blunt threat: "Pull up the GM wheat, or we will." Now, their deadline for action is fast approaching, and efforts to defuse the situation have gone nowhere, leaving researchers facing a potential confrontation this Sunday.

In Europe, genetically modified crops have met a very high level of public resistance. Derided as "frankenfoods," the crops have attracted a broad spectrum of fears, from technical concerns like the possible spread of the engineered genetic material, to vague worries about what is "natural" and the role of modern agribusiness. As a result, a number of countries have attempted to ban them outright, and many have strict labeling requirements. In general, consumer demand has kept food derived from genetically modified crops from making it to market.

(In the US, genetically modified crop products are considered indistinguishable from unmodified versions, and no specific labeling is required. There has been no significant consumer backlash, although some research fields have been vandalized.)

The lack of local consumer acceptance, however, has not stopped European researchers from working on various ways of modifying crop plants. Rothamsted, for example, participates in many international research projects, and offers training to fellows from developing nations. Even if there were no local market for the results of its research, it could still find a home in a variety of other countries.

This specific trial is actually designed to test a strain that has the potential to reduce pesticide use. Aphids, which feed on many crop plants, signal to each other via pheromones, one of which includes an alarm signal. A number of plants naturally produce this chemical (including, apparently, the peppermint), but wheat doesn't. So the researchers engineered a DNA construct that contains the two genes necessary to produce the chemical, along with sequences to let them select for the presence of the DNA in plant cells. This DNA was then inserted into wheat cells, which have now been developed into a viable wheat plant.

The next step is to actually test whether this alarm pheromone does repel aphids in real-world situations, which is why the Rothamsted researchers have planted it in a nearby field, while taking several precautions to prevent the spread of any transgenic material. They have planted buffer zones surrounding the field of genetically modified wheat, and have destroyed nearby plants following the test.

The genes used in this experiment are actually so common that they're found in many mammals; the ones used in this experiment have been modified to work well in wheat, but this has (somewhat ironically) left them most similar to the versions of the gene found in cows. That gave Take the Flour Back inspiration for its logo, which is a hybrid of a cow and a loaf of bread.

The group fears... well, just about everything, and often makes a hash of the science in the process. For example, in a summary of concerns on its website, the section entitled "Unknown health / environmental impacts" mostly describes the European public's lack of interest in foods derived from genetically modified crops; it doesn't actually list a significant health concern. It does mention the use of an antibiotic resistance gene in the work, but neglects to mention that the gene originally came from bacteria. In one paragraph, it suggests that the whole approach is flawed, while in the next, it complains that if the tests do work, they'll simply drive the aphids into the fields of farmers nearby.

In any case, the group has concluded that it must destroy this test planting. "This crop is a threat to our thriving wheat industry and our food security," the group writes, calling for what it terms 'a decontamination.' "We’d rather not have to clean it up, but there simply aren't any other avenues open to us." This action has received the support of other groups, including the UK's Green Party.

Late in April, Rothamsted responded, pointing out that their work was an effort to reduce pesticide use, that cross-contamination isn't much of a problem with wheat, and that they had taken several precautions to prevent the spread of any transgenic plants. Its open letter also points out that Rothamsted contains some experiments that have been going on for over a century, so inviting a bunch of people to invade its fields to tear up crops might lead to a truly tragic loss of some one-of-a-kind resources. The scientists invited the people at Take the Flour Back to meet and talk with the researchers, rather than tear up their crops.

The offer was not well received. The response from Take the Flour Back again shows serious misunderstandings of the science behind the tests, lumping all approaches to genetically modified crops together where convenient and focusing on the risk posed by the antibiotic resistance gene. The response ends by reiterating the group's threat: "You ask us not to pull up the GM wheat. We ask you not to recklessly endanger livelihoods and our food supply by letting it remain in the open air. We do not believe that it should be lawful for you to spread contamination in this way. If the government, through its close bio-tech industry ties, refuses to take responsibility for this problem, then we are left with no other choice."

While the district council that has jurisdiction over the Rothamsted fields has restricted public access to the area over the weekend, the protesters may find some other form of confrontation. The key question appears to be what sort of damage results.

Full disclosure: a family member volunteered at Rothamsted for several years, but was not involved in any research there.