Scientific classification Kingdom: Plantae (unranked): Angiosperms (unranked): Eudicots (unranked): Asterids Order: Solanales Family: Solanaceae Genus: Solanum Species: S. tuberosum Binomial name Solanum tuberosum L. 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. In the
region of the Andes, there are some other closely related
cultivated potato species. Potatoes 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 from the United States to Uruguay and
Peru. Genetic testing of the wide variety of cultivars and wild
species suggest that the potato has a single origin in the area of
southern Peru, from a species in the Solanum brevicaule complex.
Although Peru is essentially the birthplace of the potato, 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. Introduced to Europe 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
fact that very few varieties were 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 potato was the first vegetable inherited by the early
Australians, the Aborigines. The annual diet of an average global citizen in the first decade of
the twenty-first century would include about 33 kg (or 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. More generally, the geographic shift of potato
production has been away from wealthier countries toward
lower-income areas of the world, although the degree of this trend
is ambiguous. 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. The tubers of varieties with white
flowers generally have white skins, while those of varieties with
colored flowers tend to have pinkish skins. Potatoes are
cross-pollinated mostly by insects, including bumblebees that 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. Potato plantsAfter potato plants flower, some varieties will
produce small green fruits that resemble green cherry tomatoes,
each containing up to 300 true seeds. Potato fruit contains large
amounts of the toxic alkaloid solanine, and is therefore unsuitable
for consumption. All new potato varieties are grown from seeds,
also called "true seed" or "botanical seed" to distinguish it from
seed tubers. By finely chopping the fruit and soaking it in water,
the seeds will separate from the flesh by sinking to the bottom
after about a day (the remnants of the fruit will float). Any
potato variety can also be propagated vegetatively by planting
tubers, pieces of tubers, cut to include at least one or two eyes,
or also by cuttings, a practice used in greenhouse |
