Pure-line selection involves selecting and breeding progeny from superior organisms for a number of generations until a pure line of organisms with only the desired characteristics has been established.
What is pure line selection method?
In pureline selection, a large number of plants are selected from a self-pollinated Crop and are harvested individually, their individual progenies are evaluated and the best progeny is released as a pureline variety. Merits of Pureline Selection: i.
What is pure line selection PPT?
In Pureline selection a large number of plants are selected from a self pollinated crop and harvested individually; individual plant progenies from them are evaluated and the best progeny is released as a Pureline variety • All the individuals within a Pureline have identical genotype and any variation present within a …
What is a pure line variety?
A pure line is the progeny of a single, homozygous, self-pollinated plant. Therefore, pureline selection is also known as individual plant selection. A pureline variety is a variety obtained from a single homozygous plant of a self-pollinated crop.
What is the aim of pure line breeding?
Purpose: In self-pollinated crops pure-line selection method has several applications: (a) Improvement of Local Varieties: It is more favourite method of improvement of local varieties which have considerable genetic variability.
What is the function of pure lines?
The definition of a pure line is a result of inbreeding where animals or plants have certain characteristics that are the same through generations. An example of a pure line is the result of inbreeding of a certain flower to help it fight off diseases.
What is the main advantage of pure line selection?
Advantages of Pureline Selection Rapid method, lines are usually genetically fixed and yield trials can be immediately conducted. Plants in such variety react in similar fashion to environmental conditions, means they are uniform in performance and at the same time in appearance too.
What are the main features of pure line?
3. Features of Pure-Line Selection:
- Homogeneous: All the genotypes of a pure-line are homogeneous i.e. genetically identical and phenotypically similar.
- Non-Heritable Variation:
- Highly Uniform:
- Selection is Ineffective:
- Narrow Adaptation:
- More Prone to New Diseases:
- Isolation of Pure-Lines:
- Sources of Variation:
What are the merits of pure line selection?
How do you maintain a pure line in plant breeding?
Pure-line selection generally involves three more or less distinct steps: (1) numerous superior appearing plants are selected from a genetically variable population; (2) progenies of the individual plant selections are grown and evaluated by simple observation, frequently over a period of several years; and (3) when …
What are the merits and demerits of pure line selection method?
Demerits of pureline selection are given below:
What is genetic nature of pure line variety?
All the plants within a pure line have the same genotype. Because the parent plant was homozygous and self-fertilized. The variation present within a pure line is environmental andnon heritable. The genetic variation is produced by mechanical mixture, Natural hybridization or mutation.
What is the genetic basis of pure-line selection?
However, the genetic basis of pure lines was explained by Johannsen, a Danish biologist in 1903. Pure-line refers to the homogenous progeny of a self pollinated homozygous plant. Development of new variety through identification and isolation of single best plant progeny is known as pure-line selection or individual plant selection.
What are the basic concepts of plant breeding?
Important :Concepts General Concepts: Special Concepts: 1.Plant introduction 1. Mutation breeding 2. Pureline selection 2. Polyploidy breeding 3. Mass selection 3. Transgenic breeding 4. Pedigree method 4. Molecular breeding 5. Bulk method 6. Single Seed descent method 7. Back cross method 8. Hetrosis breeding 11.
What are the methods of selection in crop breeding?
Various selection procedures, such as pure-line selection, progeny selection, clonal selection, recurrent selection, and disruptive selection are commonly used in crop improvement programmes depending upon the mode of pollination of a crop species, the predominant gene action, and the breeding objective.
What is pure line theory of plant reproduction?
Pure Line Theory A pure line is the progeny of a single self fertilized homozygous plant. The concept of pureline was proposed by Johannsen on the basis of his studies with beans (Phaseolus vulgaris) variety called Princess.
