Vitis

Developing inflorescences of Vitis vinifera

Flower buds are formed late in the growing season and overwinter for blooming in spring of the next year. They produce leaf-opposed cymes. Vitis is distinguished from other genera of Vitaceae by having petals which remain joined at the tip and detach from the base to fall together as a calyptra or 'cap'. The flowers are mostly bisexual,[7]^:143 pentamerous, with a hypogynous disk. The calyx is greatly reduced or nonexistent in most species and the petals are joined together at the tip into one unit but separated at the base. The fruit is a berry, ovoid in shape and juicy, with a two-celled ovary each containing two ovules, thus normally producing four seeds per flower (or fewer by way of aborted embryos).[8]

Other parts of the vine include the tendrils which are leaf-opposed, branched in Vitis vinifera, and are used to support the climbing plant by twining onto surrounding structures such as branches or the trellising of a vine-training system.

In the wild, all species of Vitis are normally dioecious, but under domestication, variants with perfect flowers appear to have been selected.

The genus Vitis is divided into two subgenera Euvitis Planch. have 38 chromosomes (n=19) with berries borne on clusters[9] and Muscadinia Planch. 40 (n=20) with small custers.[10][11]

Vitis coignetiae with autumn leaves

Most Vitis species are found mostly in the temperate regions of the Northern Hemisphere in North America and eastern Asia, exceptions being a few in the tropics and the wine grape Vitis vinifera which originated in southern Europe and southwestern Asia. Grape species occur in widely different geographical areas and show a great diversity of form.

Their growth makes leaf collection challenging and polymorphic leaves make identification of species difficult. Mature grapevines can grow up to 48 cm (19 in) in diameter at breast height and reach the upper canopy of trees more than 35 m (115 ft) in height.[12]

Many species are sufficiently closely related to allow easy interbreeding and the resultant interspecific hybrids are invariably fertile and vigorous. Thus the concept of a species is less well defined and more likely represents the identification of different ecotypes of Vitis that have evolved in distinct geographical and environmental circumstances.

The exact number of species is not certain, with species in Asia in particular being poorly defined.[13] Approximately 25 species are known in North American and about 55 in eastern Asia. Just one, Vitis vinifera has Eurasian origins.[14]| Some of the more notable include:

• Vitis arizonica, The Arizona grape is native to Arizona, Utah, Nevada, California, New Mexico, Texas, and Northern Mexico.[15]
• Vitis vinifera, the European grapevine. Native to the Mediterranean and Central Asia.
• Vitis labrusca, the fox grapevine, sometimes used for winemaking and for jam. Native to the Eastern United States and Canada. The Concord grape is a common cultivar.
• Vitis riparia, the riverbank grapevine, sometimes used for winemaking and for jam. Native to the entire Eastern U.S. and north to Quebec.
• Vitis aestivalis, the summer grape, native to the Eastern United States, especially the Southeastern United States.
• Vitis rotundifolia (syn. Muscadinia rotundifolia), the muscadine, used for jams and wine. Native to the Southeastern United States from Delaware to the Gulf of Mexico.
• Vitis rupestris, the rock grapevine, used for breeding of Phylloxera resistant rootstock. Native to the Southern United States.
• Vitis coignetiae, the crimson glory vine, a species from East Asia grown as an ornamental plant for its crimson autumn foliage.
• Vitis amurensis, native to the Asian continent, including parts of Siberia and China.
• Vitis vulpina, the frost grape, native to the Eastern United States, from Massachusetts to Florida, and west to Nebraska, Kansas, and Texas.[16] Treated by some as a synonym of V. riparia.[17]
• Vitis californica, the California wild grape, or Northern California grape, or Pacific grape, is a wild grape species widespread across much of California as well as southwestern Oregon.

There are many cultivars of grapevines; most are cultivars of V. vinifera.

Hybrid grapes also exist, and these are primarily crosses between V. vinifera and one or more of V. labrusca, V. riparia or V. aestivalis. Hybrids tend to be less susceptible to frost and disease (notably phylloxera), but wine from some hybrids may have a little of the characteristic "foxy" taste of V. labrusca.

The Latin word Vitis has feminine grammatical gender,[18] and therefore species names with adjectival specific epithets take feminine forms, such as V. vinifera.[19][lower-alpha 1]

The fruit of several Vitis species are grown commercially for consumption as fresh grapes and for fermentation into wine.[21] Vitis vinifera is the most important such species.[22]

The leaves of several species of grapevine are edible and are used in the production of dolmades and Vietnamese lot leaves.[23]

Vitis for producing Sherry at Jerez.

Vitis near a house in Hontecillas.

According to the "Food and Agriculture Organization" (FAO), 75,866 square kilometres of the world is dedicated to grapes. Approximately 71% of world grape production is used for wine, 27% as fresh fruit, and 2% as dried fruit. A portion of grape production goes to producing grape juice to be used as a sweetener for fruits canned "with no added sugar" and "100% natural". The area dedicated to vineyards is increasing by about 2% per year.

The following list of top wine-producers shows the corresponding areas dedicated to grapes (regardless of the grapes’ final destination):[24]

Country	Area under vine (ha x103)	Grape production (metric ton x106)
World	7511	75.7
Spain	1021	6.0
China	830	12.6
France	786	6.3
Italy	682	8.2
Turkey	497	3.6
United States	419	7.0
Argentina	225	2.4
Iran	223	2.1
Portugal	217
Chile	211	3.1
Romania	192
Australia	149	1.7
Moldova	140
South Africa	130	2.0
India	120	2.6
Brazil	85	1.5
Bulgaria	60
New Zealand	39

Grapevines are widely cultivated by gardeners, and numerous suppliers cater specifically for this trade. The plants are valued for their decorative foliage, often colouring brightly in autumn; their ability to clothe walls, pergolas and arches, thus providing shade; and their fruits, which may be eaten as dessert or provide the basis for homemade wines. Popular varieties include:-

The following varieties have gained the Royal Horticultural Society's Award of Garden Merit:-[26]

'Palatina', a Hungary grape

Phylloxera is an American root aphid that devastated V. vinifera vineyards in Europe when accidentally introduced in the late 19th century. Attempts were made to breed in resistance from American species, but many winemakers didn't like the unusual flavour profile of the hybrid vines. However, V. vinifera grafts readily onto rootstocks of the American species and their hybrids with V. vinifera, and most commercial production of grapes now relies on such grafts.

The black vine weevil is another root pest.

Grapevines are used as food plants by the larvae of some Lepidoptera species - see list of Lepidoptera that feed on grapevines.{{Unreferenced section}}

The grapevine (typically Vitis vinifera) has been used as a symbol since ancient times. In Greek mythology, Dionysus (called Bacchus by the Romans) was god of the vintage and, therefore, a grapevine with bunches of the fruit are among his attributes. His attendants at the Bacchanalian festivals hence had the vine as an attribute, together with the thyrsus, the latter often entwined with vine branches. For the same reason, the Greek wine cup (cantharos) is commonly decorated with the vine and grapes, wine being drunk as a libation to the god.

In Christian iconography, the vine also frequently appears. It is mentioned several times in the New Testament. We have the parable of the kingdom of heaven likened to the father starting to engage laborers for his vineyard. The vine is used as symbol of Jesus Christ based on his own statement, “I am the true vine (John 15:1).” In that sense, a vine is placed as sole symbol on the tomb of Constantia, the sister of Constantine the Great, and elsewhere. In Byzantine art, the vine and grapes figure in early mosaics, and on the throne of Maximianus of Ravenna it is used as a decoration.

The vine as symbol of the chosen people is employed several times in the Old Testament. The vine and wheat ear have been frequently used as symbol of the blood and flesh of Christ, hence figuring as symbols (bread and wine) of the Eucharist and are found depicted on ostensories. Often the symbolic vine laden with grapes is found in ecclesiastical decorations with animals biting at the grapes. At times, the vine is used as symbol of temporal blessing.[31]

• Vine staff
• Annual growth cycle of grapevines
• Old vine

• Media related to Vitis at Wikimedia Commons
• Data related to Vitis at Wikispecies
• List of 48 descriptors defined in the GRAPEGEN06 project (selected from the 151 OIV descriptors published in June 2007)