SCIENTISTS are preparing to weaponise a parasitic worm’s DNA against it to prevent the loss of billions of pounds worth of food every year.

The parasitic yellow potato cyst nematode (PCN) worm devastates fields full of produce and, once established in a plot, can leave the land unworkable for potato farmers for up to 20 years.

Now an international research collaboration led by Scottish scientists has made an “exciting discovery” about the pest’s make-up.

The team, headed by Dundee University and the James Hutton Institute, is now planning to use a previously unknown genetic “signpost” to target the parasites.

Dr Sebastian Eves-van den Akker of Dundee University’s Division of Plant Sciences, based at the James Hutton Institute, said: “This is an exciting discovery which reveals the potato cyst nematode’s ‘parasitism toolkit’.

“Once we had sequenced the genome of the nematode, we uncovered a hidden genetic code, or signpost, that points towards the molecular tools the nematode uses against plants. We believe this genetic code is actually how the nematode categorises which genes it needs when infecting plants so, in a way, we can use their own signpost against them.

“Using this information we will now be able to much better target how we can prevent nematode infection.”

The US Department of Agriculture has classified the yellow PCN as potentially more dangerous than any insect or disease affecting the potato industry.

All major crops are thought to be infected by at least one species of plant-parasitic nematode, which cause damage valued at more than $80 billion (£56bn) each year.

Most feed on plant roots and “inject” the plant with destructive proteins and plant hormones.

Meanwhile, most pesticides designed to wipe out the problem have been withdrawn, necessitating the development of new ways to prevent crop infection.

The development comes as the importance of the potato as a major world food staple increases, with its use growing in countries including China.

Eves-van den Akker said: “Nematodes are the hidden enemy to crops. Thousands of these microscopic worms can infect a single plant and there can be several million in an infected field.

“If we can target these areas of the nematode’s activity then we will be better able to stop it.”

Named after the Scottish Enlightenment scientist and farmer, The James Hutton Institute operates from several sites, including two main bases in Dundee and Aberdeen, and focuses on crops, soils, land use and the environment.