Avocado

Avocado
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For the place in California, see Avocado, California. For the Pearl Jam album, see Pearl Jam (album).
Avocado

Avocado fruit and foliage, Huntington Library, California

Ripe avocado fruit and cross-section
Scientific classification
Kingdom: Plantae

Phylum: Angiosperms

Order: Laurales

Family: Lauraceae

Genus: Persea

Species: P. americana

Binomial name
Persea americana
Mill
Synonyms
Persea gratissima


The avocado (Persea americana) is a tree native to the Caribbean, Mexico,[1] South America and Central America, classified in the flowering plant family Lauraceae along with cinnamon, camphor and bay laurel. Avocado or alligator pear also refers to the fruit (technically a large berry that contains a large seed[2]) of the tree, which may be pear-shaped, egg-shaped or spherical.

Avocados are a commercially valuable fruit and are cultivated in tropical climates throughout the world (and some temperate ones, such as California), producing a green-skinned, pear-shaped fruit that ripens after harvesting. Trees are partially self-pollinating and often are propagated through grafting to maintain a predictable quality and quantity of the

Contents [hide]
1 History
1.1 Etymology
2 Cultivation
2.1 Harvest and post-harvest
2.2 Breeding
2.3 Propagation and rootstocks
2.4 Growing indoors
2.5 Diseases
2.6 Cultivation in California
2.7 A cultivars
2.8 B cultivars
2.9 Other cultivars
3 Avocado-related international trade issues
4 Culinary uses
5 Nutritional value
6 As a houseplant
7 Toxicity to animals
8 Co-evolution
9 See also
10 References
11 Further reading
12 External links

[edit] History

Native "criollo" avocados, the precursor to today's domesticated varietiesP. americana, or the avocado, originated in the state of Puebla, Mexico. The native, undomesticated variety is known as a criollo, and is small, with dark black skin, and contains a large seed.[3] The oldest evidence of avocado use was found in a cave located in Coxcatlán, Puebla, Mexico that dates to around 10,000 years BC. The avocado tree also has a long history of cultivation in Central and South America; a water jar shaped like an avocado, dating to AD 900, was discovered in the pre-Incan city of Chan Chan.[4] The earliest known written account of the avocado in Europe is that of Martín Fernández de Enciso (c. 1470–c. 1528) in 1518 or 1519 in his book, Suma De Geographia Que Trata De Todas Las Partidas Y Provincias Del Mundo..[5][6] The first written record in English of the use of the word 'avocado' was by Hans Sloane in a 1696 index of Jamaican plants. The plant was introduced to Indonesia in 1750, Brazil in 1809, the Levant in 1908, and South Africa and Australia in the late 19th century.

[edit] Etymology
The word 'avocado' comes from the Nahuatl word ahuacatl ('testicle', a reference to the shape of the fruit).[7] Avocados were known by the Aztecs as 'the fertility fruit'. In some countries of South America, such as Argentina, Bolivia, Chile, Peru, and Uruguay, the avocado is known by its Quechua name, palta. In other Spanish-speaking countries, it is called aguacate, and in Portuguese it is abacate. The fruit is sometimes called an avocado pear or alligator pear (due to its shape and the rough green skin of some cultivars). The Nahuatl ahuacatl can be compounded with other words, as in ahuacamolli, meaning 'avocado soup or sauce', from which the Mexican Spanish word guacamole derives.[8]

Also in some South American countries, the avocado is called manzana del invierno, which translates as 'winter apple'.[citation needed]

[edit] Cultivation

Persea americana, young avocado plant (seedling), complete with parted pit and roots
Worldwide avocado output in 2005Food and agriculture

Avocado fruit (cv. 'Fuerte'); left: whole, right: in section
Country Quantity (Tm) World Rank[9]
Mexico 1,040,390 1
Indonesia 263,575 2
United States of America 214,000 3
Colombia 185,811 4
Brazil 175,000 5
Chile 163,000 6
Dominican Republic 140,000 7
Peru 102,000 8
China 85,000 9
Ethiopia 81,500 10
[9]

The tree grows to 20 m (69 ft), with alternately arranged leaves 12 centimetres (4.7 in) – 25 centimetres (9.8 in) long. The flowers are inconspicuous, greenish-yellow, 5 millimetres (0.2 in) – 10 millimetres (0.4 in) wide. The pear-shaped fruit is 7 centimetres (2.8 in) – 20 centimetres (7.9 in) long, weighs between 100 grams (3.5 oz) – 1,000 grams (35 oz), and has a large central seed, 5 centimetres (2.0 in) – 6.4 centimetres (2.5 in) long.[10]

The subtropical species needs a climate without frost and with little wind. High winds reduce the humidity, dehydrate the flowers, and affect pollination. When even a mild frost occurs, premature fruit drop may occur, although the Hass cultivar can tolerate temperatures down to −1°C. The trees also need well-aerated soils, ideally more than 1 m deep. Yield is reduced when the irrigation water is highly saline. These soil and climate conditions are available only in a few areas of the world, particularly in southern Spain, Crete, the Levant, South Africa, Peru, parts of central and northern Chile, Vietnam, Indonesia, parts of southern India, Sri Lanka, Australia, New Zealand, the Philippines, Malaysia, Central America, the Caribbean, Mexico, California, Arizona, New Mexico, Texas, Florida and Ecuador. Each region has different types of cultivars. Mexico, the center of origin and diversity of this species, is the largest producer of the Hass variety, with over 1 million tonnes produced annually.

[edit] Harvest and post-harvest
An average avocado tree produces about 1200 avocados annually. Commercial orchards produce an average of 7 tonnes per hectare each year, with some orchards achieving 20 tonnes per hectare.[11] Biennial bearing can be a problem, with heavy crops in one year being followed by poor yields the next. The avocado tree does not tolerate freezing temperatures, and can be grown only in subtropical or tropical climates.

The avocado is a climacteric fruit (the banana is another), which means that it matures on the tree but ripens off the tree. Avocados used in commerce are picked hard and green and kept in coolers at 38 to 42°F (3.3 to 5.6°C) until they reach their final destination. Avocados must be mature to ripen properly. Avocados that fall off the tree ripen on the ground. Generally, the fruit is picked once it reaches maturity; Mexican growers pick Hass-variety avocados when they have more than 23% dry matter and other producing countries have similar standards. Once picked, avocados ripen in a few days at room temperature (faster if stored with other fruits such as apples or bananas, because of the influence of ethylene gas). Premium supermarkets sell pre-ripened avocados treated with synthetic ethylene to hasten the ripening process.[12] In some cases, avocados can be left on the tree for several months, which is an advantage to commercial growers who seek the greatest return for their crop; if the fruit remains unpicked for too long, however, it falls to the ground.

[edit)
http://en.wikipedia.org/wiki/Avocado