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Introduction to Mass Selection
Mass selection: In mass selection a large number of plants of different desirable phenotypes are selected and their seeds are mixed together to constitute a new variety. The plants are selected on the basis of their appearance or phenotype. The population obtained from the selected plants would be more uniform than the original population.
Applications of mass selection: 1. Improvement of local varieties.
2. Purification of existing pure line varieties. Procedure:
Merits of Mass selection:-
1. Since a large number of plants are selected the adoption of the original variety is not changed. It is generally accepted that a mix of closely related pure lines is more stable in performance over different environment than a single pure line. Thus varieties developed through mass selection are more widely adapted than pure lines.
2. Often extensive and prolonged yield trials are not necessary. This reduces the time and cost needed for developing a new variety. 3. It is a less demanding method. The breeder can devote more time to other breeding programmes. Demerits:
1. The varieties developed through mass selection show variation and are not as uniform as pure line varieties. 2. The improvement through mass selection is generally less than they through pure line selection. 3. In the absence of progeny test, it is not possible to determine if the selected plants are homozygous. 4. Due to popularity of pure line varieties, mass selection is not commonly used in improvement of self palliated crops. But it is quick and convenient method of improving old local variety in the areas or crop spp where crop improvement has just begun. 5. Varieties developed by mass selection are more difficult to identify than pure line in seed certification programme. |
Last modified: Tuesday, 7 August 2012, 8:57 AM