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lemon,one of the citrus fruitscitrus fruits,
widely used edible fruits of plants belonging to Citrus and related genera of the family Rutaceae (orange family). Included are the tangerine, citrange, tangelo, orange, pomelo, grapefruit, lemon, lime, citron, and kumquat.
..... Click the link for more information. , from a tree (Citrus limon) of the family Rutaceae (orangeorange,
name for a tree of the family Rutaceae (rue, or orange, family), native to China and Indochina, and for its fruit, the most important fresh fruit of international commerce.
..... Click the link for more information. family), probably native to India. A small tree (to about 15 ft/5 m tall) with thorny branches and purple-edged white blossoms, it requires a mild, equable climate. The European crop is centered on the islands and coasts of the Mediterranean. In the United States, lemons are grown chiefly in S California, Arizona, and Florida. The trees are prolific, and under ideal conditions can produce ripe fruit practically all the year. In the United States the fruit is cut from the tree while green, at a standard size, and the good lemons are placed in cool, dark rooms to ripen slowly; the skin grows yellow, thin, and pliable, and the quality of the fruit is similar to when ripened on the tree. The imperfect fruit is manufactured into lemon oil, lemon juice, citric acidcitric acid
or 2-hydroxy-1,2,3-propanetricarboxylic acid,
HO2CCH2C(OH)(CO2H)CH2CO2H, an organic carboxylic acid containing three carboxyl groups; it is a solid at room temperature, melts at 153°C;, and
..... Click the link for more information. , pectin, and other useful products. There are seedless varieties. The sweeter Meyer lemon is lemon crossed with either a mandarin or an orange, and the Ponderosa lemon is a lemon-citron hybrid that has grapefruit-sized fruits. Lemons have better preservative qualities than other citrus fruits and are thus more easily transported. The fruit is high in vitamin content (especially in ascorbic acid, or vitamin C) and has long been known as a preventive of scurvy. Lemons have a refreshing, acid flavor; they are used in summer drinks, such as lemonade and punch, and are often preferred to vinegar as an ingredient in sauces and salad dressings. Lemon juice is the main source of citric acid. Lemon oil, or the essential oil extracted from the skin, usually while green, is manufactured mostly in Italy and France. It is used in the making of lemon extract, perfumes and cosmetics, and furniture polish. Lemon is classified in the division MagnoliophytaMagnoliophyta
, division of the plant kingdom consisting of those organisms commonly called the flowering plants, or angiosperms. The angiosperms have leaves, stems, and roots, and vascular, or conducting, tissue (xylem and phloem).
..... Click the link for more information. , class Magnoliopsida, order Sapindales, family Rutaceae.
(Citrus limonio), a perennial evergreen subtropical plant of the genus Citrus of the family Rutaceae and the subfamily Aurantioideae. It measures from 3 to 7 m high. The branches are usually spiny. The leaves are leathery, light green, and either elongate-lanceolate or elongate-ovate. Their tips are constricted and denticulate. The leaves have translucent glandules and a specific fragrance. The flowers, which are bisexual, white, and aromatic, are on short pedicels, in small racemes, solitary, or paired. The fruit has many sections and is ellipsoid or, more rarely, nearly round. It measures 6–7 cm in length and 5–6 cm in diameter and weighs up to 120 g. The skin of the fruit is 2–5 mm thick, lemon-yellow, and smooth or with oily glandules; it is bitter and has a characteristic aroma. The pulp is a greenish pale-yellow, fine grained, juicy, and very sour. The seeds are light in color and smooth; 20 and more are found in each fruit.
In the subtropics of the USSR there are three picking seasons —spring, summer, and fall. Between pickings the plant is relatively dormant. Lemon trees are thermophilic and photophilic. Spring growth begins when the average daily temperature is above 10°C. The period of growth and development lasts 200–220 days, and the optimum temperature for growth and flowering is 17°-18°C. Without sufficient light, large leaves form, and the trees grow and bear fruit poorly. The lemon is the most hygrophilous citrus fruit.
Native to Southeast Asia, the lemon has not been found in wild form. It is cultivated in the subtropics of the Mediterranean region, the United States, Mexico, and Argentina. It has been raised in the USSR for more than 200 years. The lemon grows best in open areas, such as the Black Sea shore of the Caucasus, the Azerbaijan SSR, and Middle Asia, where it is grown in trenches. In many places lemons are also raised indoors.
The fruits, or lemons, of the lemon tree have 3.5–8.1 percent acids (chiefly citric) and 1.9–3.0 percent sugar. For every 100 g there are 45–140 mg of vitamin C; the fruit also contains vitamins P and B, pectin substances, iron, phosphorus, calcium, sodium, potassium, and magnesium. Lemons are eaten fresh or used for producing juice and citric acid. Their peel contains lemon oil, which has a distinctive fragrance.
In the USSR several varieties are grown, including Novogruzinskii, Limon Kuznera, and Bez Koliuchek (without spines). Lemons are propagated from grafts and cuttings. Grafted lemon trees begin fruiting in the third or fourth year. A tree yields 150–300 fruits annually. In open areas lemons are grown as creeping or semidwarf trees. In the spring the plants are planted in warm areas protected from cold winds, on loose soil that is rich in humus and has good water and air drainage. Creeping varieties are planted in rows spaced 2.5–4 m apart; semidwarf plantings are spaced 2.5–3 apart, with 4 m between rows. Under each tree 10–50 kg of manure, as well as 20–300 g of nitrogen, 80–350 g of phosphorus, and 50–120 g of potassium fertilizers, are applied (quantity depending on the soil and the age of the tree). During the period of growth and development, unwanted shoots are removed and shoots that grow too vigorously are pruned.
A. D. ALEKSANDROV