Daily Herald | Posted: Tuesday, August 19, 2008 11:00 pm
33Why?
Those who follow world food production will know that acreage devoted to spuds is growing at a faster rate than for any other crop. The reason? The world food shortage and the fact that demand for grains is outstripping supply. (The news that the United States is on track for its second-largest corn crop and fourth-largest soybean crop is welcome, but we're talking worldwide production here.) In many countries, it is apparently the practice to let land lie fallow for a time between grain crops, and farmers have found that they can sneak in a crop of potatoes during that period. Potatoes mature more rapidly than the grains and possess a host of nutritional values. According to the Aug. 2 issue of New Scientist, potatoes are more nutritious than the grains, require less land and water, can tolerate worse conditions, give four times the complex carbohydrates per unit land area than grains, have several vitamins and a higher-quality protein (they make more of the essential amino acids that our bodies cannot manufacture). And in this day of concern about both obesity and food insufficiency, they contain virtually no fat.
Potatoes originated in Peru, of course, and were taken to Europe early on. But they did not catch on very quickly. It is said that cooks for the court of Queen Elizabeth I threw away the tubers and served the boiled leaves and stems, promptly causing many cases of nightshade poisoning. But Europe's peasants adopted the tubers even though the upper classes did not, and spuds' benefits were eventually recognized. Marie Antoinette, famous for her remark to let the French peasants eat cake since they had too little bread, apparently wore potato flowers to suggest an alternative to cake.
The popularity of the potato eventually swept across Europe and in Ireland, in particular, it became virtually the sole food crop for the peasants. But a Mexican fungus-like organism, Phytophthora infestans, commonly called late blight, was brought to Europe with some seed potatoes from the United States in 1845, and there devastated the European crop. The famous Irish Potato Famine of 1846-1847 was not limited to Ireland. It took hundreds of thousands of lives all across Europe. (See Cecil Woodham-Smith's "The Great Hunger" for a fascinating though macabre account.)
The sad news is that we still do not have good blight-resistant potatoes. John Niederhauser, an American scientist, was given a $200,000 prize in 1990 for the first in a considerable line of potatoes with some resistance, but the blight has evolved resistance so that potato farmers spend as much as 16 percent of their budgets just for fungicide. New Scientist quotes a Scottish agriculturalist who said he had to spray 12 times last season, and in tropical areas that may require spraying every few days. Can we really afford to make potatoes into even more of a critical crop for the world's peoples when another round of blight evolution may cause a potato famine redux?
Potatoes are tetraploids, indicating that they have a complex genetic system that makes traditional breeding techniques very difficult. It seems that genetic engineering, or genetic modification, is our clear-cut best hope. This will take genes for blight resistance (eight are known among wild potato relatives) and insert them into our favorite edibles. Germany and the Netherlands now have promising strains under development, but at best it will be several years before they can come to market.