Citrus is a genus of flowering trees and shrubs in the rue family, Rutaceae. Plants in the genus produce citrus fruits, including crops such as oranges, mandarins, lemons, grapefruits, pomelos, and limes. The genus Citrus is native to South Asia, East Asia, Southeast Asia, Melanesia, and Australia. Various citrus species have been used and domesticated by indigenous cultures in these areas since ancient times. From there its cultivation spread into Micronesia and Polynesia by the Austronesian expansion ; and to the Middle East and the Mediterranean via the incense trade route, and onwards to Europe and the Americas.
The grapefruit is a subtropical citrus tree known for its relatively large, sour to semi-sweet, somewhat bitter fruit. The interior flesh is segmented and varies in color from pale yellow to dark pink/red.
The mandarin orange, also known as mandarin or mandarine, is a small, rounded citrus tree fruit. Treated as a distinct species of orange, it is usually eaten plain or in fruit salads. Tangerines are a group of orange-colored citrus fruit consisting of hybrids of mandarin orange with some pomelo contribution.
Citrus cavaleriei, the Ichang papeda, is a slow-growing species of papeda that has characteristic lemon-scented foliage and flowers.
The tangelo, Citrus × tangelo, is a citrus fruit hybrid of a Citrus reticulata variety, such as mandarin orange or tangerine, and a Citrus maxima variety, such as a pomelo or grapefruit. The name is a portmanteau of 'tangerine' and 'pomelo'.
The trifoliate orange, Citrus trifoliata, is a member of the family Rutaceae. Whether the trifoliate oranges should be considered to belong to their own genus, Poncirus, or be included in the genus Citrus is debated. The species is unusual among citrus for having deciduous, compound leaves and pubescent (downy) fruit.
The Key lime or acid lime is a citrus hybrid native to tropical Southeast Asia. It has a spherical fruit, 2.5–5 centimetres in diameter. The Key lime is usually picked while it is still green, but it becomes yellow when ripe.
An oroblanco, oro blanco, or sweetie (Israel) is a sweet seedless citrus hybrid fruit similar to grapefruit. It is often referred to as oroblanco grapefruit.
Ponkan ; Citrus poonensis; "Chinese Honey Orange") is a high-yield sweet Citrus cultivar with large fruits in the size of an orange. It is a citrus hybrid, though it was once thought to be a pure mandarin.
Rangpur, Citrus × limonia or Citrus reticulata × medica, sometimes called the rangpur lime, mandarin lime or lemandarin, is a hybrid between the mandarin orange and the citron. It is a citrus fruit with a very acidic taste and an orange peel and flesh.
An orange, also called sweet orange to distinguish it from the bitter orange, is the fruit of a tree in the family Rutaceae. Botanically, this is the hybrid Citrus × sinensis, between the pomelo and the mandarin orange. The chloroplast genome, and therefore the maternal line, is that of pomelo. The sweet orange has had its full genome sequenced.
The citrange is a citrus hybrid of the sweet orange and the trifoliate orange.
Citrus tristeza virus (CTV) is a viral species of the genus Closterovirus that causes the most economically damaging disease to its namesake plant genus, Citrus. The disease has led to the death of millions of Citrus trees all over the world and has rendered millions of others useless for production. Farmers in Brazil and other South American countries gave it the name "tristeza", meaning sadness in Portuguese and Spanish, referring to the devastation produced by the disease in the 1930s. The virus is transmitted most efficiently by the brown citrus aphid.
The lemon is a species of small evergreen tree in the flowering plant family Rutaceae, native to Asia, primarily Northeast India (Assam), Northern Myanmar, and China.
Cold-hardy citrus is citrus with increased frost tolerance and which may be cultivated far beyond traditional citrus growing regions. Citrus species and citrus hybrids typically described as cold-hardy generally display an ability to withstand wintertime temperatures below −5 to −10 °C. Cold-hardy citrus may be generally accepted 'true' species or hybrids involving various other citrus species. All citrus fruits are technically edible, though some have bitter flavors often regarded as unpleasant, and this variability is also seen in cold-hardy citrus fruits. Those listed as "inedible fresh" or "semi-edible" can be cooked to make marmalade.
Citrus taxonomy refers to the botanical classification of the species, varieties, cultivars, and graft hybrids within the genus Citrus and related genera, found in cultivation and in the wild.
Citrumelo is also called Swingle citrumelo trifoliate hybrid, because it is cold hardy and is a hybrid between a 'Duncan' grapefruit and a trifoliate orange, developed by Walter Tennyson Swingle.
Citrus reshni also known as Cleopatra mandarin is a citrus tree that is commonly used in agriculture as a rootstock of different cultivated species of citrus, mostly orange, grapefruit, tangerine and lemon. It originated in India and later was introduced to Florida from Jamaica in the mid-nineteenth century.
Citrus blight is a type of blight that occurs in tropical and semi-tropical regions. Specializing in infecting citrus trees, the blight is found in North America, the Caribbean, South America, South Africa and Australia. The blight injures plants by forming blockages in xylem and phloem, inhibiting resource distribution and resulting in plant die-back and smaller fruit yields. As of 2020 there is no cure for the blight, and neither the causal agent nor spreading mechanism is known.
Volkamer lemon, often misspelled Volckamer lemon, is known as 沃 尔卡默柠檬 in Chinese, citron de Volkamer in French, limone Volkameriano in Italian, and chanh Volkamer in Vietnamese. It is a Citrus hybrid cultivated for its edible fruit. The specific epithet (volkameriana) honors German botanist Johann Christoph Volkamer. It is a taxonomical synonym of Citrus limon.
