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The potato is a starchy, tuberous crop from the perennial nightshade Solanum tuberosum L. The word "potato" may refer either to the plant itself or the edible tuber. In the Andes, where the species is indigenous, there are some other closely related cultivated potato species. Potatoes were introduced outside the Andes region approximately four centuries ago,[1] and have since become an integral part of much of the world's food supply. It is the world's fourth-largest food crop, following maize, wheat, and rice.[2]
Wild potato species occur throughout the Americas from the United States to southern Chile.[3] The potato was originally believed to have been domesticated independently in multiple locations,[4] but later genetic testing of the wide variety of cultivars and wild species proved a single origin for potatoes in the area of present-day southern Peru and extreme northwestern Bolivia (from a species in the Solanum brevicaule complex), where they were domesticated approximately 7,000–10,000 years ago.[5][6][7] Following centuries of selective breeding, there are now over a thousand different types of potatoes.[6] Over 99% of the presently cultivated potatoes worldwide descended from varieties that originated in the lowlands of south-central Chile, which have displaced formerly popular varieties from the Andean highlands.[8][9]
The annual diet of an average person in the first decade of the 21st century included about 33 kg (73 lb) of potato.[citation needed] 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 now leads the world in potato production, and nearly a third of the world's potatoes are harvested in China and India.[10]
The potato was first domesticated in the region of modern-day southern Peru and extreme northwestern Bolivia[5] between 8000 and 5000 BC.[6] It has since spread around the world and become a staple crop in many countries.
According to conservative estimates, the introduction of the potato was responsible for a quarter of the growth in Old World population and urbanization between 1700 and 1900.[28] Following the Spanish conquest of the Inca Empire, the Spanish introduced the potato to Europe in the second half of the 16th century. The staple was subsequently conveyed by European mariners to territories and ports throughout the world. The potato was slow to be adopted by distrustful European farmers, but soon enough it became an important food staple and field crop that played a major role in the European 19th century population boom.[7] However, 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.[25] Thousands of varieties still persist in the Andes however, where over 100 cultivars might be found in a single valley, and a dozen or more might be maintained by a single agricultural householdThere are about 5,000 potato varieties worldwide. Three thousand of them are found in the Andes alone, mainly in Peru, Bolivia, Ecuador, Chile, and Colombia. They belong to eight or nine species, depending on the taxonomic school. Apart from the 5,000 cultivated varieties, there are about 200 wild species and subspecies, many of which can be cross-bred with cultivated varieties. Cross-breeding has been done repeatedly to transfer resistances to certain pests and diseases from the gene pool of wild species to the gene pool of cultivated potato species. Genetically modified varieties have met public resistance in the United States and in the European Union.The major species grown worldwide is Solanum tuberosum (a tetraploid with 48 chromosomes), and modern varieties of this species are the most widely cultivated. There are also four diploid species (with 24 chromosomes): S. stenotomum, S. phureja, S. goniocalyx, and S. ajanhuiri. There are two triploid species (with 36 chromosomes): S. chaucha and S. juzepczukii. There is one pentaploid cultivated species (with 60 chromosomes): S. curtilobum. There are two major subspecies of Solanum tuberosum: andigena, or Andean; and tuberosum, or Chilean.[19] The Andean potato is adapted to the short-day conditions prevalent in the mountainous equatorial and tropical regions where it originated; the Chilean potato, however, native to the Chiloé Archipelago, is adapted to the long-day conditions prevalent in the higher latitude region of southern Chile.The International Potato Center, based in Lima, Peru, holds an ISO-accredited collection of potato germplasm.[21] The international Potato Genome Sequencing Consortium announced in 2009 that they had achieved a draft sequence of the potato genome.[22] The potato genome contains 12 chromosomes and 860 million base pairs, making it a medium-sized plant genome.[23] More than 99 percent of all current varieties of potatoes currently grown are direct descendants of a subspecies that once grew in the lowlands of south-central Chile.[24] Nonetheless, genetic testing of the wide variety of cultivars and wild species affirms that all potato subspecies derive from a single origin in the area of present-day southern Peru and extreme northwestern Bolivia (from a species in the Solanum brevicaule complex).Most modern potatoes grown in North America arrived through European settlement and not independently from the South American sources; however, at least one wild potato species, Solanum fendleri, is found as far north as Texas and is used in breeding for resistance to a nematode species that attacks cultivated potatoes. A secondary center of genetic variability of the potato is Mexico, where important wild species that have been used extensively in modern breeding are found, such as the hexaploid Solanum demissum, as a source of resistance to the devastating late blight disease.[25] Another relative native to this region, Solanum bulbocastanum, has been used to genetically engineer the potato to resist potato blight.Potatoes yield abundantly with little effort, and adapt readily to diverse climates as long as the climate is cool and moist enough for the plants to gather sufficient water from the soil to form the starchy tubers. Potatoes do not keep very well in storage and are vulnerable to molds that feed on the stored tubers and quickly turn them rotten; however, crops such as grain can be stored for several years with a low risk of rot.
Potato Recipes Recipes for Kids in Urdu for Desserts for Dinner for Chicken with Ground Beef In Hindi for Cakes for Cookies Photos
Potato Recipes Recipes for Kids in Urdu for Desserts for Dinner for Chicken with Ground Beef In Hindi for Cakes for Cookies Photos
Potato Recipes Recipes for Kids in Urdu for Desserts for Dinner for Chicken with Ground Beef In Hindi for Cakes for Cookies Photos
Potato Recipes Recipes for Kids in Urdu for Desserts for Dinner for Chicken with Ground Beef In Hindi for Cakes for Cookies Photos
Potato Recipes Recipes for Kids in Urdu for Desserts for Dinner for Chicken with Ground Beef In Hindi for Cakes for Cookies Photos
Potato Recipes Recipes for Kids in Urdu for Desserts for Dinner for Chicken with Ground Beef In Hindi for Cakes for Cookies Photos
Potato Recipes Recipes for Kids in Urdu for Desserts for Dinner for Chicken with Ground Beef In Hindi for Cakes for Cookies Photos
Potato Recipes Recipes for Kids in Urdu for Desserts for Dinner for Chicken with Ground Beef In Hindi for Cakes for Cookies Photos
Potato Recipes Recipes for Kids in Urdu for Desserts for Dinner for Chicken with Ground Beef In Hindi for Cakes for Cookies Photos
Potato Recipes Recipes for Kids in Urdu for Desserts for Dinner for Chicken with Ground Beef In Hindi for Cakes for Cookies Photos
Potato Recipes Recipes for Kids in Urdu for Desserts for Dinner for Chicken with Ground Beef In Hindi for Cakes for Cookies Photos
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