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The potato is a starchy, tuberous crop from the perennial Solanum tuberosum of the Solanaceae family (also known as the nightshades). The word potato may refer to the plant itself as well as the edible tuber. In the region of the Andes, there are some other closely related cultivated potato species. First introduced outside the Andes region four centuries ago, today potatoes have become an integral part of much of the world’s cuisine and are the world’s fourth-largest food crop, following rice, wheat, and maize. Long-term storage of potatoes requires specialised care in cold warehouses and such warehouses are among the oldest and largest storage facilities for perishable goods in the world. Wild potato species occur throughout the Americas, from the United States to Uruguay. Today over 99% of all cultivated potatoes worldwide are descendants of a subspecies indigenous to south-central Chile. Based on historical records, local agriculturalists, and DNA analyses, the most widely cultivated variety worldwide, Solanum tuberosum ssp. tuberosum, is believed to be indigenous to the Chiloé Archipelago where it was cultivated as long as 10,000 years ago. However, genetic testing of the wide variety of cultivars and wild species suggests that all potatoes have a single origin in the area of southern Peru (from a species in the Solanum brevicaule complex), where potatoes were first domesticated between 3000 BC and 2000 BC. Introduced to Europe by Spain in 1536, the potato was subsequently conveyed by European mariners to territories and ports throughout the world. Thousands of varieties persist in the Andes, where over 100 cultivars might be found in a single valley, and a dozen or more might be maintained by a single agricultural household. Once established in Europe, the potato soon became an important food staple and field crop. But lack of genetic diversity, due to the very limited number of varieties initially introduced, left the crop vulnerable to disease. In 1845, a plant disease known as late blight, caused by the fungus-like oomycete Phytophthora infestans, spread rapidly through the poorer communities of western Ireland, resulting in the crop failures that led to the Great Irish Famine. The annual diet of an average global citizen in the first decade of the 21st century included about 33 kg (73 lb) of potato. However, the local importance of potato is extremely variable and rapidly changing. It remains an essential crop in Europe (especially eastern and central Europe), where per capita production is still the highest in the world, but the most rapid expansion over the past few decades has occurred in southern and eastern Asia. China is now the world’s largest potato-producing country, and nearly a third of the world’s potatoes are harvested in China and India.
Potato plants are herbaceous perennials that grow about 60 cm (24 in) high, depending on variety, the culms dying back after flowering. They bear white, pink, red, blue, or purple flowers with yellow stamens. In general, the tubers of varieties with white flowers have white skins, while those of varieties with colored flowers tend to have pinkish skins. Potatoes are cross-pollinated mostly by insects, including bumblebees, which carry pollen from other potato plants, but a substantial amount of self-fertilizing occurs as well. Tubers form in response to decreasing day length, although this tendency has been minimized in commercial varieties. 
Flowers of a potato plant 
Russet potatoes with sprouts 
Potato plants
Potato output in 2005 The potato contains vitamins and minerals, as well as an assortment of phytochemicals, such as carotenoids and polyphenols. Chlorogenic acid constitutes up to 90% of the potato tuber polyphenols. Others polyphenols found in potatoes are 4-O-caffeoylquinic (crypto-chlorogenic acid), 5-O-caffeoylquinic (neo-chlorogenic acid), 3,4-dicaffeoylquinic and 3,5-dicaffeoylquinic acids. A medium-size 150 g (5.3 oz) potato with the skin provides 27 mg of vitamin C (45% of the Daily Value (DV)), 620 mg of potassium (18% of DV), 0.2 mg vitamin B6 (10% of DV) and trace amounts of thiamin, riboflavin, folate, niacin, magnesium, phosphorus, iron, and zinc. The fiber content of a potato with skin (2 g) is equivalent to that of many whole grain breads, pastas, and cereals. In terms of nutrition, the potato is best known for its carbohydrate content (approximately 26 grams in a medium potato). The predominant form of this carbohydrate is starch. A small but significant portion of this starch is resistant to digestion by enzymes in the stomach and small intestine, and so reaches the large intestine essentially intact. This resistant starch is considered to have similar physiological effects and health benefits as fiber: It provides bulk, offers protection against colon cancer, improves glucose tolerance and insulin sensitivity, lowers plasma cholesterol and triglyceride concentrations, increases satiety, and possibly even reduces fat storage. The amount of resistant starch in potatoes depends much on preparation methods. Cooking and then cooling potatoes significantly increased resistant starch. For example, cooked potato starch contains about 7% resistant starch, which increases to about 13% upon cooling. The nutrients of the potato seem to be fairly evenly distributed between the flesh and the skin. For a medium potato, with and without the skin, nutritiondata.com gives the following:
Potato planting in Washington 
Potato field in Fort Fairfield, Maine 
Potatoes grown in a tall bag are common in gardens as they increase potato yield and minimize the amount of digging required at harvest 
Various potato dishes 
French fries served with a hamburger 
Poutine: Fried potatoes, cheese curds, and gravy
From Wikipedia, the free encyclopedia : Wholesale table potatoes |
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