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Variety is a low-level taxonomic rank used in botanical nomenclature.
In botanical nomenclature or biological nomenclature, variety is a low-level taxonomic rank below that of species and signifies members of different populations can interbreed easily, but not usually such that all traits (appearance attributes) will run true, and in fact usually will blend. As such, it gets a ternary name (a name in three parts). The Variety taxonomy is most often used in classifying plants, but is on occasion used colloquially and industrially to differentiate between pedigree bloodlines in the animal kingdom as well. Official zoological nomenclature does not recognize the rank of variety, only sub-species.
A variety will have an appearance distinct from other varieties, but will hybridize freely with those other varieties (if brought into contact). Usually varieties will be geographically separate from each other, or as in the case of animals, bred carefully in controlled segregation from other varieties.
Example: The pincushion cactus, Escobaria vivipara (Nutt.) Buxb., is a wide-ranging variable species occurring from Canada to Mexico, and found throughout New Mexico below about 2600 m. Nine varieties have been described. Where the varieties of the pincushion cactus meet, they intergrade. The variety Escobaria vivipara var. arizonica is from Arizona, while Escobaria vivipara var. neo-mexicana is from New Mexico.
Notes
- To plant breeders, at least in countries that are signatory to the UPOV Convention, "variety" or "plant variety" is a legal term.
- In zoological nomenclature, the only officially-regulated rank below that of species is that of subspecies. Forms and morphs are used instead of varieties if needed, but are unregulated by the ICZN.
- In bacteriological nomenclature "variety" and "subspecies" are used interchangeably.
- In viticulture, what is referred to as "grape varieties" are in reality cultivars rather than varieties according to usage in the International Code of Nomenclature for Cultivated Plants, since they are propagated by cuttings and have properties that are not stable under sexual reproduction (seed plants). However, usage of the term variety is so entrenched in viticulture that a change to cultivar is unlikely.
See also
- Breed
- Cultivar
- Form (botany)
- Hybrid (biology)
- Race (biology)
- Subvariety
- Trinomial nomenclature
- Variety (plant)
Wikipedia content modification information:
- This page was last modified on 26 November 2008, at 00:43.
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