Pure Line

(redirected from pure lines)
Also found in: Dictionary, Medical.

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.

I. I. TOLSTORUKOV

References in periodicals archive ?
Mr Barker said: "Hybrids clearly have far more strength in depth than pure lines these days too.
Use of the back crossed males greatly simplified our research because it gave us access to pure lines of male date palms," Malek recalled while adding that varieties of dates are notoriously hard to identify even by experienced growers.
The verticals symbolize the owner of the state, while the concrete blocs with pure lines the spirit of the majority of the people.
The artist, Romhein, said the sculpture uses simple and pure lines to demonstrate the universality and simplicity of the duality of man and woman.
Hubbard specializes in state-of-the-art selection programs to improve the performance of their pure lines, and offers a range of products to respond to current and future needs of the broiler industry.
Liao's neat studio seems to echo the pure lines of her ceramics while another potter's studio seems barred against the light and intruding distractions and another's is lined with windows overlooking a garden.
In addition to their more generous size, these two new launches enrich the Riviera MAGNUM line with several advanced design features: a case redesigned with one side shaped like a car radiator grille; new hollowed hands; a larger crown; and a new rubber strap with pure lines, secured by an adjustable triple folding clasp.
It originally was created as a sake bottle, with simple curves and pure lines.
It is characterised by pure lines, a specific profile, remarkable ergonomic qualities and the use of innovative materials.
The second set of contrasts ignored the pure lines altogether and for each of the five parental strains, compared the mean of the four hybrid strains to which it contributed to the mean of all 10 outbred lines.
NYSE: MOT), a global leader in wireless communications, is adding four beautiful shades to the smooth, pure lines of the iconic PEBL, showcasing the driving importance of color inspiration in the mobile space.
Topics covered in the chapters include crop biology, heterosis, pollination control mechanisms, hybrid seed production, and maintenance of inbred and pure lines.