Defra has approved field trials of genetically modified barley that scientists say could reduce the need for synthetic fertilisers.

The trial, run by researchers at the Crop Science Centre in Cambridge, will evaluate whether improved crop interaction with naturally occurring soil fungi can result in more sustainable food production.

See also: Debate: Gene editing the pros and cons for farming

The barley variety has been genetically modified to boost expression levels of the NSP2 gene.

This gene is naturally present in barley and boosting its expression enhances the crop’s capacity to engage with mycorrhizal fungi.

Five-year study

Starting this April, the small field trials will take place over the next five years at three sites operated by the Crop Science Centre, which is a partnership between the National Institute of Agricultural Botany (Niab) and the University of Cambridge.

Professor Giles Oldroyd is leading the trial and said there was an urgent need to satisfy the demands of a growing population, while respecting limits on natural resources.

“We believe biotechnology can be a valuable tool for expanding the options available to farmers around the world,” he said.

The trial will also test varieties of barley that have been gene-edited to suppress their interaction with arbuscular mycorrhizal fungi (AMF).

The scientists say this will help them to better quantify how the microbes support plant development by assessing the full range of interactions.

They will measure yield and grain nutritional content in varieties with an enhanced capacity to engage the fungi and those in which it has been suppressed, while comparing both to the performance of a typical barley plant.

Prof Oldroyd said: “The ultimate goal is to understand whether this same approach can be used to enhance the capacity of other food crops to interact with soil fungi in ways that boost productivity without the need for synthetic fertilisers.”

The trial will assess production under high- and low-phosphate conditions. It will also investigate additional potential benefits of the relationship with mycorrhizal fungi, such as protecting crops from pests and disease.

Risks and criticisms

The Advisory Committee on Releases to the Environment (Acre) said it was satisfied the trial could go ahead after it assessed the risk to human health and the environment.

But Pat Thomas, director of environmental group Beyond GM, questioned the narrowness of Acre’s considerations when it comes to genetically modified organism field trials.

“Acre’s remit in assessing field trial applications is extremely limited and often the most important questions, the kinds of question that farmers might ask, are outside Acre’s remit,” Ms Thomas told Farmers Weekly.  

“These include whether re-engineering a plant is the most effective, most reliable and most easily adopted approach for farmers who wish to improve soil health and therefore plant health and resilience.”

Ms Thomas said there were a lot of unknowns that could make an open field trial more risky, “particularly related to escape and how the engineered plant might interact with the wider environment”.

Controls

But Acre acknowledged some of these issues in its advice and has given scientists eight control measures to follow.

The advice includes ensuring that the 20m surrounding the trial sites is planted with a non-cereal crop and that cereal volunteers are controlled (prior to flowering) in this area during the trial.

Ms Thomas added: “The kinds of conditions that interfere with AMF proliferation are caused by modern industrial farming practices such as heavy application of phosphorus-containing fertilisers and fungicides.

“Agroecological farmers would argue that we already have the tools and protocols to address these issues and that these can be put into practice today, rather than waiting five years for the results of this trial and, assuming good results, another several years before a genetically engineered barley might become commercially available.”