The Well-Travelled Tuber
A Brief History of the Potato
From a food science perspective, the fascinating thing about the potato is its nutritional value; potatoes provide everything except calcium and vitamins A and D, which are readily available from milk. Thus, a simple diet of potatoes and milk can provide a healthy diet for people with little access to other foods, such as fresh fruits and vegetables.
Potatoes are also easy to grow. They are perfectly suited to Irish soil, and a large crop can be grown on a tiny plot of land. Few tools are required and, in an emergency, a crop can even be grown and harvested with one's bare hands. In preparation, no threshing, grinding or baking is required, just a pot and a peat fire — both items that were readily available in the humblest of Irish cabins.
Further, the potato produced more food per acre than any other crop Irish farmers had grown before. Not only that, it also produced more calories per acre, an added bonus for people who were constantly engaged in hard physical labour. Indeed, rye was the only grain that could be depended on to ripen in the short, rainy summers that prevailed in that region of Northern Europe that extended from the North Sea to the Ural Mountains. Replace this rye with potatoes, though, and four times as many people could live on produce from the same amount of soil that produced the rye. Better still, potatoes could be planted in the fallow fields required for the successful cultivation of rye. Eventually, potatoes came to be propagated in lazybeds throughout the country. Lazybeds could be prepared on any type of ground regardless of stones, soil quality or even how level it was. Nothing could inhibit potatoes growing in these self-draining beds.
So, to the 19th century Irish peasant, who raised a pig not to be eaten but to pay the annual rent, a crop that could feed your family and your pig all year round without the added burden of being labour intensive was attractive. Thus, with its great nutritional value, coupled with its ease of cultiavation, the potato soon became Ireland's food of the poor.
During the 17th and 18th centuries, the potato experienced a surge of popularity as war-torn Europe found that the potato was easy to hide from pillaging soldiers. Unlike grains that needed to be harvested and stored in barns, potatoes could be left in the ground and only removed as required. The Belgians were the first to benefit from the practice of leaving a good stock of potatoes underground in the 1680s, during the wars of Louis XIV. The practice was later appreciated in Germany, during the wars of the Spanish Succession (1700-1713), in Prussia and Poland during the Seven Years War (1756-63), and in Russia and Northern Europe during the Napoleonic Wars (1792-1815). From the soldiers' perspective, it was easier to grab a sack of grain from a barn than to dig for potatoes!
However, though the potato was cultivated throughout Europe, it was only in Ireland that it becme the sole subsistence crop. Unfortunately, though, they had no method of preserving it for emergency rations.
Centuries before, though, farmers in the altiplano — a high elevation desert that spans portions of Chile, Argentina and Bolivia — had devised a clever way of preserving potatoes before they were ruined by frost. They would let the potatoes, which are comprised of 80% water, freeze overnight. They would then squeeze the water out, leaving them with a freeze-dried version called chu_o. This could be stored in a sealed room for up to ten years, and could then be easily reconstituted in boiling water whenever it was needed.
With this method of preserving potatoes, Andean farmers were able to save potatoes for times of need. In this way, potatoes successfully prevented famine in the altiplano. In Ireland, though, where no method for preserving potatoes existed, dependence on the potato ended up being the cause of famine. Several varieties of potato were grown in Ireland, and the very worst of them — lumpers — were what the peasants ate. By the time the "lumpers went black" in 1845, the potato was so entrenched as the mainstay of the Irish peasant diet, that its absence meant starvation.
Some scientists suspect that the potatoes in Ireland were brought over from the altiplano, though it is not known how they travelled from the New World to the Old World. It is certain, though, that much thanks is due to the Andean farmers who first collected potatoes from the wild and cultivated them, as their endeavors ultimately provided Eurpoe with a major food staple. It is ironic, though, that in addition to giving Europe the potato, they likely also gave Ireland the pathogen that made the lumpers go black in 1845.
According to Dr. Jean Ristano of North Carolina State University, the Ia strain of the haplotype P. infestans that heralded the late blight that caused the Irish famine, more than likely originated from the Andean region:
"The pathogen probably moved in infected seed potatoes shipped from South America. In 1840s Mexico, Santa Anna was fighting a war, so commercial potatoes were not being grown there. But the Peruvians were shipping potatoes to New Zealand and Australia, and over land and by sea to the US ports of Philadelphia and New York and to Europe. Furthermore, bat guano, used as a fertiliser, was also being shipped out of Peru. [Thus], circumstantial evidence from ship records suggests South America [as the source of the pathogen that caused the famine]."
Late blight is still a major worldwide problem. Dr. Ristano believed that South American is likely to be the best location for searching for resistant potato varieties in the wild, as her data suggests that the host and pathogen have evolved in this region the longest. If the resistant varieties are in fact found in South America, it will be an excellent example of things coming full circle.