Norwich plant scientists have outlined plans for a field trial of genetically-modified (GM) potatoes which they believe could help defeat a major crop disease.

The Sainsbury Laboratory (TSL) has applied to Defra for permission to test the effectiveness of genes which could make potatoes resistant to late blight – a destructive disease responsible for significant crop losses across the UK and Europe.

Three separate resistance genes, discovered in related wild plants, have been transferred into commercial Maris Piper potatoes in the laboratory. But now scientists want to test how these altered varieties respond in a realistic open-air environment, without relying on pesticides.

Prof Jonathan Jones, lead scientist for the project, said: 'Late blight is the most important potato disease across the world. Estimates vary, but it costs between $4bn and $7bn of losses a year, plus the cost of controlling it with chemical applications.

'Farmers spray 10 or 15 times a year, more if it is wet, to control blight and it is very destructive, so we want to put genes in that enable the plant to spot the disease and activate its own defences.

'The organic farmers will tell you that there are already varieties that are blight-resistant, but none reach the top 20 of varieties that are planted, because they all have other properties which render them less attractive commercially. Maris Piper is a good all-rounder for this trial.

'What I hope to do is to show that it is possible to generate a blight-immune potato, and society will have the final say on whether that technology is deployed, or whether they would rather farmers carried on spraying chemicals.'

The cultivation of GM crops was a source of controversy when the technology emerged 20 years ago, and opponents still harbour concerns including the potential for contamination of conventional or organic crops, and a lack of studies on the potential impact on human health.

Prof Jones said, if the trial is approved and successful, the commercial viability of blight-resistant GM potatoes will ultimately depend on consumer demand and public opinion.

'We would hope by then we will be confident that the public mood would not be appalled at the prospect,' he said. 'My sense is that there are a lot more people in the 'I'm not bothered' camp than in the 'I'm strenuously opposed' camp. But we have to respect those who have reservations about the GM method even though, in the opinion of every authoritative science body, there are no science-based grounds for concern.'

At last week's Norfolk Farming Conference, also held on the Norwich Research Park, veteran farmer and commentator David Richardson asked whether the centre's world-renowned expertise in plant genetics would be applied in the UK after the country's exit from the EU – which currently regulates against the commercial growing of GM crops.

He said: 'Can we look forward to the ability to use these technologies or will we be held back by European regulations?'

George Freeman, the Mid Norfolk MP who is also chair of the prime minister's policy board, responded: 'I don't talk about GM any more, I talk about the opportunities of agri-genetics and advanced breeding. We have got the potential right here to do that and we would be bonkers if we didn't use it.'

CONTROLLING THE TRIAL

If consent is granted, the trial will take place on a small parcel of land, no larger than 1,000sqm, at the Norwich Research Park between May 2017 and November 2020.

The Sainsbury Laboratory's application – a revised submission to a proposal which was approved last summer – says steps will be taken to contain the GM plants within the trial area and prevent them from mixing with conventional crops.

They will be grown at least 20m away from other potato varieties, and a 3m fence will prevent human interference or damage by large animals. At the end of each season during the four-year trial period, all harvested material will be sealed and removed from site to be incinerated at an authorised waste disposal facility.

Following the end of the trial, the plot will be left fallow and monitored for any remaining 'volunteer' plants, which will be destroyed immediately.

The application to Defra says: 'In addition to the absence of known harmful properties of any of the genetic elements present in the modified potatoes, no harmful properties are expected to emerge when the above-mentioned genes and traits are combined. Finally, tubers will be destroyed at harvest and thus there will be no risk of the genetically modified material entering the food chain.'

What do you think of the proposed trial? Contact chris.hill@archant.co.uk.