How potatoes could save the world

They require very little water, mature in as little as 50 days and can yield between two and four times more food per hectare than wheat or rice.

"The recent shocks to the food supply are very real and that means we could potentially be moving into a reality where there is not enough food to feed the world" - said Pamela Anderson, director of the International Potato Centre in Lima, a non-profit scientific group.

Like others, she says the potato is part of the solution to the hunger caused by higher food prices, a population that is growing by one billion people each decade, climbing costs for fertiliser and diesel and more cropland being sown for biofuel production.

To focus attention on this, the United Nations named 2008 the International Year of the Potato - calling the vegetable a 'hidden treasure'.

Governments are also turning to the tuber. Peru's leaders, frustrated by a doubling of wheat prices in the past year, have started encouraging bakers to use potato flour to make bread. Potato bread is being given to schoolchildren, prisoners and the military, in the hope the trend will catch-on.

Supporters say that it tastes just as good, but not enough mills are set up to make potato flour. "We have to change people's eating habits" - Ismael Benavides, Peru's agriculture minister, said. "People got addicted to wheat when it was cheap."

Even though the potato emerged in Peru 8,000 years ago near Lake Titicaca, Peruvians eat fewer potatoes than people in Europe. Belarus leads the world in consumption, with each inhabitant devouring an average of 376lb a year.

China, a huge rice consumer that historically has suffered devastating famines, has become the world's top potato grower, while in sub-Saharan Africa, the potato is expanding more than any other crop. India has told food experts it wants to double potato production in the next five to ten years. In Latvia, sharp price rises caused bread sales to drop by 10 to 15 per cent in January and February, as consumers bought 20 per cent more potatoes.

The developing world is where most new potato crops are being planted - and, as consumption rises, poor farmers have a chance to earn more money. "The countries themselves are looking at the potato as a good option for both food security and also income generation" - Ms Anderson said.

The potato is already the world's third most-important food crop after wheat and rice. Potatoes come in some 5,000 types and Peru is sending thousands of seeds this year to the Doomsday Vault near the Arctic Circle - contributing to a gene bank for food crops that was set up in case of a global disaster.

In colours ranging from alabaster white to bright yellow and deep purple - and, with countless shapes, textures and sizes - potatoes offer inventive chefs a chance to create new, eye-catching dishes. The Lima potato centre says they are a great source of complex carbohydrates, which release their energy slowly and have only 5 per cent of the fat content of wheat.

They also have a quarter of the calories of bread and, when boiled, have more protein than corn and nearly twice the calcium. They contain vitamin C, iron, potassium and zinc.

Science is moving fast. Genetically modified potatoes that resist 'late blight' are being developed by the German chemicals group BASF. 'Late blight' is the disease that led to famine in Ireland during the 19th century and still causes about 20 per cent of potato-harvest losses in the world, the company says.

Scientists say that farmers who use clean, virus-free seeds can boost yields by 30 per cent and be cleared for export. That would generate more income for farmers and encourage more production, as companies could sell speciality potatoes abroad, instead of just having them turned into frozen chips or crisps.