Research & Innovation

A new strain of genetically modified potato appears immune to the devastating fungus responsible for the great Irish Famine of 1845, research has shown.

Late blight, caused by the organism phytophthora infestans, remains the potato farmer’s greatest enemy to this day.

In the latest of a series of field trials, conducted in 2012, the fungus was unable to break down the defences of any GM potatoes.

Non-modified plants grown at the trial site were all infected after being denied protection from chemicals.

However, nobody can say at this stage how long the GM strain will hold out against blight, which is notorious for its ability to overcome resistance.

Scientists are now conducting further research aimed at identifying multiple resistance genes that will thwart future blight attacks.

“Breeding from wild relatives is laborious and slow and by the time a gene is successfully introduced into a cultivated variety, the late blight pathogen may already have evolved the ability to overcome it,” said lead scientist Professor Jonathan Jones, from the Sainsbury Laboratory.

“With new insights into both the pathogen and its potato host, we can use GM technology to tip the evolutionary balance in favour of potatoes and against late blight.”

The Famine of 1845 was a disaster for the poorer people of Ireland who depended on potatoes. Over the next 10 years, more than 750,000 men, women, and children died and another 2m left emigrated.

Because of late blight, potatoes are one of the crops most affected by chemical pesticides. In Europe, farmers typically spray a potato crop 10-15 times.

The aim of the study was to produce a crop that could fight off blight without the aid of chemicals.

Results from the trials appear in the journal Philosophical Transactions of the Royal Society B.