27) With advancements in genetics molecular biology and tissue culture, new traits have been incorporated into crop into crop plants. Explain the main steps in breeding a new genetic variety of a crop.
Dear student,
Steps involved in breeding a new genetic variety of crop are as follows:
1. Collection of variability: The differences among the individuals of the population for a given trait show the variation of that trait. Some variations occur due to genetic (genetic variations). This is the basis of any breeding programme. The sum total of all the alleles of genes present in a crop and its wild relatives constitutes the germplasm. Collection of germplasm is the first andstep for successful breeding programme. Germplasm consists of:-
3. Cross hybridisation among the selected parents: This is a time consuming process. Mating between two (or more) individuals or lines differing in genotype is called hybridisation. It is the most common method of creating genetic variation by bringing traits of two individuals (parents) together in the progeny. The desired characters often have to be combined from two different parents. For example, high protein quality of one parent may need to be combined with disease resistance from another parent.
4. Selection and testing of superior recombinants: In this step, the plants which have the combination of desired characters, are selected from the progeny of hybrids. The process is crucial to the success of the breeding programme and requires careful scientific evaluation of progeny. The selection process yields plants that are superior to both the parents. The selected plants are self-pollinated for several generations till they reach a state of uniformity (homozygosity).
5. Testing, release and commercialisation of new cultivars: The newly selected lines are evaluated for their yield and other traits of quality, disease, etc. The evaluation is done by growing the selected lines first in the research fields. After this the material is evaluated in the farmers field for at least three growing seasons. A new material that is found superior to the existing varieties may be released as a new variety after giving it a name. The government notifies each new release.
Regards
Steps involved in breeding a new genetic variety of crop are as follows:
1. Collection of variability: The differences among the individuals of the population for a given trait show the variation of that trait. Some variations occur due to genetic (genetic variations). This is the basis of any breeding programme. The sum total of all the alleles of genes present in a crop and its wild relatives constitutes the germplasm. Collection of germplasm is the first andstep for successful breeding programme. Germplasm consists of:-
- cultivated improved varieties
- improved varieties that are no more cultivated
- old varieties and wild species related to the crop species.
3. Cross hybridisation among the selected parents: This is a time consuming process. Mating between two (or more) individuals or lines differing in genotype is called hybridisation. It is the most common method of creating genetic variation by bringing traits of two individuals (parents) together in the progeny. The desired characters often have to be combined from two different parents. For example, high protein quality of one parent may need to be combined with disease resistance from another parent.
4. Selection and testing of superior recombinants: In this step, the plants which have the combination of desired characters, are selected from the progeny of hybrids. The process is crucial to the success of the breeding programme and requires careful scientific evaluation of progeny. The selection process yields plants that are superior to both the parents. The selected plants are self-pollinated for several generations till they reach a state of uniformity (homozygosity).
5. Testing, release and commercialisation of new cultivars: The newly selected lines are evaluated for their yield and other traits of quality, disease, etc. The evaluation is done by growing the selected lines first in the research fields. After this the material is evaluated in the farmers field for at least three growing seasons. A new material that is found superior to the existing varieties may be released as a new variety after giving it a name. The government notifies each new release.
Regards