The results of controversial field scale GM wheat trials in the UK have been published this week. The experiment conducted in 2012 and 2013 aimed to show that wheat with a genetic modification to produce aphid disrupting pheromone EßF could play an important role in aphid control. EßF is an alarm pheromone released by aphids to warn others of the presence of predators such as ladybirds and lacewings. The pheromone is produced naturally by some plants such as peppermint, and by using genetic material from peppermint the team at Rothamsted Research were able to produce an EßF producing wheat variety, which they had hoped could reduce the need for insecticide applications. The trials went ahead despite protests and threats of vandalism. Security for the site cost the taxpayer over £2 million compared to the cost of the trial itself at £732,000.
The results however, were not what the team at expected, at the farm level the crop did not significantly repel aphids compared to a conventional control crop as was expected and shown in initial experiments in the laboratory. If anything that work serves to illustrate the importance of field scale trials of new agricultural technology, what works in the lab does not always work in the real conditions on the farm.
There may be a number of reasons for the results, the wet conditions encountered in 2013 meant a low threat from aphids anyway, and less chance of a significant difference being detected. In addition some believe that the aphids may have simply become accustomed to the constant presence of the alarm pheromone.
Despite the results attracting negative publicity from the media, and claims that the work was a waste of money, the research team are claiming a number of successes, first in demonstrating stable genetic engineering of an insect pheromone into a crop plant, which has not been done before. They have also identified areas for further work such as engineering the plant to only release the pheromone when the aphids arrive or intermittently to better mimic more natural conditions. Further work could also focus on testing the wheat in areas and conditions where there is a greater risk of aphids.
What is clear is that the planting of a commercial GM wheat variety in the UK is some way off, even if the trials had proved a success there would still be significant work in getting the variety tested for food safety issues, licensed and cleared by EU regulators, and then, and not least in overcoming consumer resistance to GM food.