BRITAIN'S favourite potatoes, including Maris Piper and King Edwards, may not exist in 20 years time.

Scientists have warned that diseases are killing crops of traditional potato varieties, which are often used to make chips.

Now, experts are attempting to create new breeds of potatoes that can resist diseases before some of Britain's favourite varieties are wiped out.

Max Coleman, a potato scientist at the Royal Botanic Gardens in Edinburgh, said: "People are familiar with King Edward potatoes and like them but don't realise they're no longer a viable crop.

"We can guarantee that in 20 years time we won't be growing Maris Piper because they won't be viable.

"Even now King Edward is one you don't see so much.

"But they have this reputation so people still want them."

Maris Piper and King Edwards are often used for popular potato side dishes, including chips, mash and roast spuds, because of their taste and versatility.

Crisps could be safe for now, with big name brands such as Walkers using alternatives varieties such as Lady Rosetta, Hermes, and Saturna.

But traditional varieties are being ravaged by diseases because of the way they're grown.

All potatoes grown from tubers left to sprout after the previous year's crops have been harvested.

But that makes them vulnerable to diseases such as late blight, which can spread through a whole crop.

The new potato project aims to create more sustainable ways of growing potatoes without the need for using stronger pesticides.

Scientists will focus on potatoes grown in Scotland, a major producer of potatoes for the whole of the UK.

Dr Coleman added: "Blight is a living thing and it evolves.

"You can have a potato variety that is resistant now and won't be in 10 years' time."

He continued: "We have to run to stand still. These problems are never truly solved - we manage them."

Scientists from the Royal Botanic Gardens and the James Hutton Institute in Dundee have begun crossing modern varieties of potato with wild breeds from South and Central America.

Wild varieties have a natural resistance to blight but often don't resemble the potatoes customers are used to buying as they can appear knobbly or have different coloured flesh.

Gordon Stark, who runs a potato import and export business in Perthshire, said retailers are reluctant to replace familiar potatoes with varieties that are not guaranteed to sell well.

He said customers also like to stick with what they know.

Mr Stark said: "Blight is a problem. "It's very difficult for new varieties to break into the market - very difficult.

"There are new varieties coming to the market but 80 per cent of the market is 20 per cent of the varieties, maybe even 90 per cent.

"None of them are particularly blight resistant."

He added: "To get a substantial new variety is going to be very hard.

"The customer and the retailers don’t want to change."

A potato shortage last year caused packs of crisps to rise in price, we revealed last month.

Meanwhile, fans fear there could be another KFC shortage after the chicken chain's main supplier DHL quit.

There was a huge salad and vegetable shortage two years ago after poor weather in Europe affected crops.