Vanilla (genus)

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Vanilla
Temporal range: Early Cretaceous - Recent
109–0Ma
Flat-leaved Vanilla (Vanilla planifolia)
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Monocots
Order: Asparagales
Family: Orchidaceae
Subfamily: Vanilloideae
Tribe: Vanilleae
Subtribe: Vanillinae
Genus: Vanilla
Plumier ex Mill., 1754
Species

see List of Vanilla species

Green: Distribution of Vanilla species
Synonyms

Myrobroma Salisb.[1]

Vanilla, the vanilla orchids, form a flowering plant genus of about 110 species in the orchid family (Orchidaceae). The most widely known member is the Flat-leaved Vanilla (V. planifolia), from which commercial vanilla flavoring is derived. It is the only orchid widely used for industrial purposes (in the food industry and in the cosmetic industry). Another species often grown commercially but not on an industrial scale is the Pompona Vanilla (V. pompona).

This evergreen genus occurs worldwide in tropical and subtropical regions, from tropical America to tropical Asia, New Guinea and West Africa. It was known to the Aztecs for its flavoring qualities. The genus was established in 1754 by Plumier, based on J. Miller. The word vanilla, derived from the diminutive of the Spanish word vaina (vaina itself meaning sheath or pod), simply translates as little pod.

Description[edit]

Flat-leaved Vanilla (Vanilla planifolia) habitus

This genus of vine-like plants has a monopodial climbing habitus. They can form long thin stems with a length of more than 35 m, with alternate leaves spread along their length. The short, oblong, dark green leaves of Vanilla are thick and leathery, even fleshy in some species. But there are also a significant number of species that have their leaves reduced to scales or have become nearly or totally leafless and appear to use their green climbing stems for photosynthesis. Long and strong aerial roots grow from each node.

The racemose inflorescences short-lived flowers arise successively on short peduncles from the leaf axils or scales. There may be up to 100 flowers on a single raceme, but usually no more than 20. The flowers are quite large and attractive with white, green, greenish yellow or cream colors. The flowers' sepals and petals are similar. The lip is tubular-shaped and surrounds the long, bristly column, opening up, as the bell of a trumpet, at its apex. The anther is at the top of the column and hangs over the stigma, separated by the rostellum. Most Vanilla flowers have a sweet scent.

Blooming occurs only when the flowers are fully grown. Each flower opens up in the morning and closes late in the afternoon on the same day, never to re-open. If pollination has not occurred meanwhile, it will be shed. The flowers are self-fertile but need pollinators to perform this task. The flowers are presumed to be pollinated by stingless bees (e.g. Melipona) and certain hummingbirds, which visit the flowers primarily for nectar. Hand pollination is the most reliable method in commercially grown Vanilla.

The fruit is termed "vanilla bean", though true beans are fabaceaen eudicots not at all closely related to orchids. Rather, the vanilla fruit is technically an elongate, fleshy and later dehiscent capsule 10–20 cm long. It ripens gradually for 8 to 9 months after flowering, eventually turning black in color and giving off a strong aroma. Each pod contains thousands of minute seeds, and both the pods and seeds within are used to create vanilla flavoring.

Vanilla species are used as food plants by the larvae of some Lepidoptera species, such as the wooly bear moths Hypercompe eridanus and H. icasia. Vanilla plantations require some sort of tree planting for the orchids to climb up on; off-season or when abandoned, they may serve as habitat for animals of open forest, e.g. on the Comoros for Robert Mertens' Day Gecko (Phelsuma robertmertensi).

Species[edit]

The taxonomy of the genus Vanilla is complex.[2] This is a partial list of species or synonyms:

References[edit]

  1. ^ "Genus: Vanilla Mill.". Germplasm Resources Information Network. United States Department of Agriculture. 2003-10-01. Retrieved 2011-03-02. 
  2. ^ Bory, Séverine; Michel Grisoni, Marie-France Duval and Pascale Besse (July 21, 2007). "Biodiversity and preservation of vanilla: present state of knowledge". Genetic Resources and Crop Evolution (Springer Netherlands) 55 (4): 551–571. doi:10.1007/s10722-007-9260-3. ISSN 1573-5109. 
  3. ^ "GRIN Species Records of Vanilla". Germplasm Resources Information Network. United States Department of Agriculture. Retrieved 2011-03-02. 
  • Portéres, R. Le Vanillier et la Vanille dans le monde in Bouriquet, G. Encyclopédie Biologique. Vol. 46. Paul Lechavelier, Paris, 1954.
  • Rolfe, R.A. A revision of the genus Vanilla. Kew Bull. 439-478, 1895.

External links[edit]