A genetically-modified potato with resistance to late blight disease has progressed successfully through the latest stage of trials at The Sainsbury Laboratory.
Late blight is a devastating plant disease that can wipe out whole fields of potato crops unless several applications of chemical fungicides are used to combat the infection.
The latest phase of field trials conducted by The Sainsbury Laboratory on the Norwich Research Park follow successful experiments to modify commercial Maris Piper potatoes with late blight resistance genes found in wild relatives of the potato plant, which could reduce farmers' reliance on costly and environmentally-damaging chemicals.
Scientists have also been able to switched off - or "silence" - certain genes to make the potatoes less prone to bruise damage and cold-induced sweetening, the accumulation of sugars during cold storage which can blacken potatoes when cooked at high temperatures, for instance when frying chips or crisps.
And the trials in Norfolk this summer suggest that these genetic benefits have been gained without detrimental impact on the yield or performance of the potatoes in the field.
"We have developed a potato plant that looks fine in terms of yield, it is comparable to non-GM Maris Piper. But it has the benefits of blight resistance, reduced susceptibility to bruising and with lower levels of reducing sugars," said Prof Jonathan Jones of The Sainsbury Laboratory.
"The really exciting thing about this trial is that our new line also shows resistance to tuber blight - the same pathogen that causes late blight can get into tubers and rot them. This will reduce losses in storage for potato growers."
Regulation of GM crops means these new potatoes will be subject to strict scrutiny before they are available to Norfolk farmers. With the UK's future relationship with the EU still uncertain, the project will continue with trials.
"The future regulatory framework is an imponderable," said Prof Jones. "But we have shown that the technology works. The improvements were made in Maris Piper, the most planted UK potato variety. If you want to solve problems in the field, you need to do so in a popular, preferred variety.
"We want to make agriculture more sustainable, to achieve that goal, we need to find solutions to the problems farmers and consumers face. By replacing chemistry with genetics for disease control in potatoes we can reduce the environmental footprint of the food grown here in the UK."
The Sainsbury Laboratory was granted permission earlier this year by Defra to proceed with three years of field trials in controlled conditions.
The next phase of trials, funded by the BBSRC (Biotechnology and Biological Sciences Research Council), will see more extensive yield trials for 12 lines of improved potato plants, before the final GM Maris Piper can be taken forward for regulatory assessment and commercialisation.