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In biology, strain is a low-level taxonomic rank used in three related ways.

Contents 1 Microbiology and virology 2 Plants 3 Rodents 4 External links 5 References

[edit] Microbiology and virology

A strain is a genetic variant or subtype of a microorganism (e.g. virus or bacterium or fungus). For example, a "flu strain" is a certain biological form of the influenza or "flu" virus. Compare clade.

[edit] Plants

The term has no official ranking status in botany; the term refers to the collective descendants produced from a common ancestor that share a uniform morphological or physiological character.^[1] A strain is a designated group of offspring that have descended from a modified plant, produced either by conventional breeding or by biotechnological means or result from genetic mutation. As an example, some rice strains are made by inserting new genetic material into a rice plant,^[2] all the descendants of the genetically modified rice plant are a strain with a unique genetic code that is passed on to later generations; the strain designation, which is normally a number or a formal name, covers all the plants that descent from the originally modified plant. The rice plants in the strain can be breed to other rice strains or cultivars, and if desirable plants are produced, these are further breed to stabilize the desirable traits; the stabilized plants that can be propagated and come true, are given a cultivar name and released into production to be used by farmers.

[edit] Rodents

A mouse or a rat strain is a group of animals that is genetically uniform. Strains are used in laboratory experiments. Mouse strains can be inbred, mutated or genetically engineered, while rat strains are usually inbred.

[edit] External links

• International Mouse Strain Resource (IMSR)
• Rat strain index
• E. coli strain index

[edit] References