THE OUTBREAK IN WALES of a highly contagious new potato disease has, we learn, sent “panic” through the British countryside. This might seem an exaggeration, but the word is well chosen, for after the other successive blows that have recently befallen British agriculture, the threat of a fresh epidemic afflicting to the once mighty potato seems, symbolically, the final straw.

The most important edible vegetable the world has known, the potato rose to power from the end of the 18th century to win iconic status in our fields, hearts and menus. We like to think of the oak as the plant that most accurately reflects the national character, but in truth, alongside the Irish, we are potato people: knobbly, adaptable, resilient and slightly grubby.

But now, just as the rural community seemed to be recovering, Solanum tuberosum is under attack from Clavibacter michiganensis sepedonicus, or ring rot, a bacterium that turns the common tattie to rotten slime. Townies may shrug; the chips around the fish seem unaffected. But the psychological impact of this latest agricultural disaster can be understood only when our rural history is seen, as it were, through the eyes of the potato.

Spuds have been eaten for 7,000 years, and often controversially. When first brought to Europe from South America by the Spanish in the late 16th century, the tuber was viewed with deep suspicion. Henry VIII believed it to be an aphrodisiac, but others looked less kindly on the root, associating it with madness, syphilis, chronic wind and leprosy. The Swiss botanist Gaspard Bauhin believed the potato, as a cousin to the evil mandrake root and deadly nightshade, possessed diabolical powers, while William Cobbett, the great rural reformer, loathed this “lazy root”, considering it the cause of “all slovenliness, filth, misery and slavery”.

The population growth in England and Ireland between 1750 and 1850 was linked to the abundance of potatoes, and like others, Cobbett feared that a crop so easy to cultivate would turn generations of workers into layabouts. Malthus rightly pointed out that a population dependent on a single crop was toying with calamity.

Initially the Catholic Church was also fiercely anti-spud, since the Bible makes no mention of potatoes; Russians spurned them as “Satan’s Apples” and until the middle of the 19th century the Japanese regarded potatoes as mere cattle fodder. Gastronomes sneered: “I appreciate the potato only as a protection against famine,” sniffed Anthelme Brillat-Savarin, arguably the first French foodie. “I know of nothing more eminently tasteless.”

Even today, the potato gets a bad press, in the form of “couch potatoes” and “potato heads”. That former Vice-President Dan Quayle could not spell so modest and ubiquitous a word was redoubled evidence of stupidity. It is no accident that Robert Atkins, purveyor of the eponymous diet, should launch his broadside against the spud, the humble workhorse of nutrition, the vegetable fall-guy.

Yet the potato is a social force that has shaped history in profound and lasting ways. Easy to plant and harvestable with the bare hands, the potato provided cheap nutrition; but when the crop failed, as it did most dramatically in Ireland in 1845, it could bring famine, mass emigration and huge social dislocation.

Mostly, however, the potato was a force for good, the tuber that got things done: the American West was won by men and women fortified by potatoes; Napoleon’s army marched on its stomach which was often full of potatoes (pommes frites first appeared in 1818).

Potatoes, the largest single source of vitamin C in the 20th century, affected working hours and the length of fingernails, changed patterns of housework, cuisine and agriculture. The spud was even, briefly, a fashion statement, when Marie Antoinette wore purple potato blossoms in her hair.

The potato is the most democratic and liberating of vegetables, for by providing cheap and nutritious food, it freed many men and women from the permanent anxiety over where the next meal might come from. Oats and corn could be fickle, but the versatile, all-weather potato offered independence.

The rural labourer with his potato patch was in some measure defended against both hunger and exploitation: which is why many landowners bitterly opposed potato cultivation. “Had the potato not existed,” writes Larry Zuckerman, the greatest historian of the potato, then “19th-century England would have been hungrier and harder-pressed.”

The ancient Andeans who first cultivated potatoes associated them with mystical, healing properties, and their descendants, the Incas, worshipped potato deities and developed a system for telling the time based on how long it took to cook a potato. The vegetable is still held in special reverence. Think of Van Gogh’s Potato Eaters, painted in 1885: “I have tried,” the painter wrote, “to make clear how these people, eating their potatoes under the lamplight, have dug the earth with those very hands they put in the dish.” Van Gogh would never have painted broccoli or rocket.

The horror at the new outbreak of ring rot threatens an industry worth £580 million a year, but it should be understood in cultural as well as economic terms. The British farming community is still reeling from BSE and foot- and-mouth, and deeply angered by a government that seems to understand the countryside little, and care less; now even the potato, hitherto a hardy and dependable ally, seems to be falling apart.

Farmers might feel that the Incan spud gods have turned against them, but perhaps they should take heart from the story of the potato itself: an unglamorous hero, the victim of superstition and fashion, disease and disdain, the potato has seen good times and bad, but it has always pulled through when the chips were down.

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