The tomato









The tomato is native to South America. Genetic evidence shows that the progenitors of tomatoes were herbaceous green plants with small green fruit with a center of diversity in the highlands of PeruThese early Solanums diversified into the dozen or so species of tomato recognized today. One species, Solanum lycopersicum, was transported to Mexico where it was grown and consumed by prehistoric humans. The exact date of domestication is not known. Evidence supports the theory that the first domesticated tomato was a little yellow fruit, ancestor of L. cerasiforme,[citation needed] grown by the Aztecs of Central Mexico who called it xitomatl (pronounced), meaning plump thing with a navel, and later called tomatl by other Mesoamerican peoples. Aztec writings mention tomatoes were prepared with peppers, corn and salt, likely to be the original salsa recipe.
The word tomato comes from a word in the Nahuatl language, tomato. The specific name, lycopersicum, means "wolf-peach".
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Varieties




There are many (around 7500) tomato varieties grown for various purposes. Heirloom tomatoes are becoming increasingly popular, particularly among home gardeners and organic producers, since they tend to produce more interesting and flavorful[citation needed] crops at the cost of disease resistance and productivity. Hybrid plants remain common, since they tend to be heavier producers and sometimes combine unusual characteristics of heirloom tomatoes with the ruggedness of conventional commercial tomatoes.
Tomato varieties are roughly divided into several categories, based mostly on shape and size. "Slicing" or "globe" tomatoes are the usual tomatoes of commerce; beefsteak are large tomatoes often used for sandwiches and similar applications - their kidney-bean shape makes commercial use impractical along with a thinner skin and being not bred for a long shelf life; globe tomatoes are of the category of canners used for a wide variety of processing and fresh eating; oxheart tomatoes can range in size up to beefsteaks, and are shaped like large strawberries; plum tomatoes, or paste tomatoes (including pear tomatoes), are bred with a higher solid content for use in tomato sauce and paste and are usually oblong; pear tomatoes are obviously pear shaped and based upon the San Marzano types for a richer gourmet paste; cherry tomatoes are small and round, often sweet tomatoes generally eaten whole in salads; and grape tomatoes which are a more recent introduction are smaller and oblong used in salads; campari tomatoes are also sweet and noted for their juiciness, low acidity, and lack of mealiness; they are bigger then cherry tomatoes, but are smaller than plum tomato.
Early tomatoes and cool-summer tomatoes bear fruit even where nights are cool, which usually discourages fruit set There are also varieties high in beta carotenes and vitamin A, hollow tomatoes and tomatoes which keep for months in storage.
Tomatoes are also commonly classified as determinate or indeterminate. Determinate, or bush, types bear a full crop all at once and top off at a specific height; they are often good choices for container growing. Determinate types are preferred by commercial growers who wish to harvest a whole field at one time, or home growers interested in canning. Indeterminate varieties develop into vines that never top off and continue producing until killed by frost. They are preferred by home growers and local-market farmers who want ripe fruit throughout the season. As an intermediate form, there are plants sometimes known as "vigorous determinate" or "semi-determinate"; these top off like determinates but produce a second crop after the initial crop. The majority of heirloom tomatoes are indeterminate, although some determinate heirlooms exist.

A variety of specific cultivars, including Brandywine (biggest red), Black Krim (lower left corner), Green Zebra (top right), et cetera.
Most modern tomato cultivars are smooth surfaced, but some older tomato cultivars and most modern beefsteaks often show pronounced ribbing, a feature that may have been common to virtually all pre-Columbian cultivars. While virtually all commercial tomato varieties are red, some tomato cultivars - especially heirlooms - produce fruit in colors other than red, including yellow, orange, pink, black, brown, ivory, white, and purple, though such fruit is not widely available in grocery stores, nor are their seedlings available in typical nurseries, but must be bought as seed, often via mail-order. Less common variations include fruit with stripes (Green Zebra), fuzzy skin on the fruit (Fuzzy Peach, Red Boar), multiple colors (Hillbilly, Burracker's Favorite, Lucky Cross), etc.
There is also a considerable gap between commercial and home-gardener cultivars; home cultivars are often bred for flavor to the exclusion of all other qualities, while commercial cultivars are bred for such factors as consistent size and shape, disease and pest resistance, and suitability for mechanized picking and shipping, as well as their ability to be picked before fully ripening. The most commonly home grown tomato is the Beefsteak variety.
Tomatoes grow well with 7 hours of sunlight a day. A fertilizer with the ratio 5-10-10, often sold as tomato fertilizer or vegetable fertilizer can be used for extra growth and production, but manure or compost work well, too.
Diseases and pests





























Tomato cultivars vary widely in their resistance to disease. Modern hybrids focus on improving disease resistance over the heirloom plants. One common tomato disease is tobacco mosaic virus, and for this reason smoking or use of tobacco products are discouraged around tomatoes, although there is some scientific debate over whether the virus could possibly survive being burned and converted into smoke.[23] Various forms of mildew and blight are also common tomato afflictions, which is why tomato cultivars are often marked with a combination of letters which refer to specific disease resistance. The most common letters are: V - verticillium wilt, F - fusarium wilt strain I, FF - fusarium wilt strain I & II, N - nematodes, T - tobacco mosaic virus, and A - alternaria.

Another particularly dreaded disease is curly top, carried by the beet leafhopper, which interrupts the lifecycle, ruining a nightshade plant as a crop. As the name implies, it has the symptom of making the top leaves of the plant wrinkle up and grow abnormally.
Some common tomato pests are stink bugs, cutworms, tomato hornworms and tobacco hornworms, aphids, cabbage loopers, whiteflies, tomato fruitworms, flea beetles, red spider mite, slugs,[24] and Colorado potato beetles.
Fruit or vegetable?

Botanically, a tomato is the ovary, together with its seeds, of a flowering plant: therefore it is a fruit. However, the tomato is not as sweet as those foodstuffs usually called fruits and, from a culinary standpoint, it is typically served as part of a salad or main course of a meal, as are vegetables, rather than at dessert in the case of most fruits. As noted above, the term vegetable has no botanical meaning and is purely a culinary term. Originally the controversy was that tomatoes are treated as a fruit in home canning practices. Tomatoes are acidic enough to be processed in a water bath rather than a pressure cooker as "vegetables" require.
This argument has had legal implications in the United States. In 1887, U.S. tariff laws that imposed a duty on vegetables but not on fruits caused the tomato's status to become a matter of legal importance. The U.S. Supreme Court settled the controversy on May 10, 1893 by declaring that the tomato is a vegetable, based on the popular definition that classifies vegetables by use, that they are generally served with dinner and not dessert (Nix v. Hedden (149 U.S. 304)).[34] The holding of the case applies only to the interpretation of the Tariff Act of March 3, 1883, and the court did not purport to reclassify the tomato for botanical or other purpose. Tomatoes have been designated the state vegetable of New Jersey. Arkansas took both sides by declaring the "South Arkansas Vine Ripe Pink Tomato" to be both the state fruit and the state vegetable in the same law, citing both its culinary and botanical classifications. In 2006, the Ohio House of Representatives passed a law that would have declared the tomato to be the official state fruit, but the bill died when the Ohio Senate failed to act on it. However, in April 2009 a new form of the bill passed, making the tomato the official fruit of the state of Ohio. Tomato juice has been the official beverage of Ohio since 1965. A.W. Livingston, of Reynoldsburg, Ohio, played a large part in popularizing the tomato in the late 1800s.
Due to the scientific definition of a fruit, the tomato remains a fruit when not dealing with US tariffs. Nor is it the only culinary vegetable that is a botanical fruit: eggplants, cucumbers, and squashes of all kinds (such as zucchini and pumpkins) share the same ambiguity.
الموضوع الأصلي: Tomato // الكاتب: الصباح النجار // المصدر: خير بلدنا الزراعي

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