Pure Line

Also found in: Dictionary, Thesaurus, Medical, Legal, Financial, Wikipedia.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Pure Line


the homogenous generations of repeatedly self-pollinating plants or self-fertilizing animals, in which most genes are homozygous. The term was introduced in 1903 by the Danish geneticist W. Johannsen, who proved by experimentation on legumes that pure lines exhibit analogous phenotypes under identical conditions.

Pure lines are obtained from a single ancestor and are maintained by self-pollinization and selection. Individuals in pure lines repeat over several generations the same genetically fixed traits. Pure lines are important in agriculture inasmuch as they are the main structural elements of plant varieties. Hybridization of two pure lines often results in heterosis in the first hybrid generation; certain hybrid varieties of corn are obtained in this way.

The term “pure line” is sometimes incorrectly applied to inbred lines, which are the progeny of animals or cross-pollinated plants obtained from a single pair of ancestors and maintained over a number of generations by constant crossing of related individuals and by selection. Such lines are almost always used in genetic research on higher organisms. For example, “pure line” laboratory mice are used to study carcinogenesis and cancer treatment.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Canonical discriminant analysis is an example of multivariate technique that represents the multivariate dispersion of qualitative explanatory variables, e.g., pure lines of beans.
It does not exclude good performance at high density on the presupposition that the final outcome is a pure line variety where just intra- and not intergenotypic competition prevails [10,18].
The PURE line debuts with two pasta sauces, PURE SUGO and PURE SUGO ARROSTO.
Soffiips has also introduced the Softlips Pure line of natural and organic items and Softlips Lip Relief for treatment of cold sores.
Rather than seeking to produce a pure line of anarchist thought, the book traces influences, continuities and discontinuities, networks of association: a culture of anarchist ideas refracted through novels, essays, journalism, and political pamphlets, in fields ranging from sexology to town planning.
Mrs Beckham's show was a brilliant succession of pure line and slim seduction, but then you would hardly expect chunky stuff from the thinnest woman on the planet.
Chantal launched its new Pure line of bakeware and tea accessories, made of ceramic stoneware and free of coloring agents.
The Fourier transform of the complex Fourier series is a one-sided pure line spectrum at multiples of the gear rotation rate.
In the field, inbreeding depression was restricted to lines that showed poor pure strain performance, and these strains also showed poor general combining ability, whereas strains with good pure line performance showed out-breeding depression and good general combining ability.
The F4:5 line was selected in Keiser, AR, in 1998, and seeds were bulked as a pure line for subsequent yield trials.