What is marker-assisted backcross breeding?
Marker-assisted backcrossing is the simplest form of MAS, in which the goal is to incorporate a major gene from an agronomically inferior source (the donor parent) into an elite cultivar or breeding line (the recurrent parent).
What is the advantage of marker-assisted breeding?
Marker-assisted selection may greatly increase the efficiency and effectiveness for breeding compared to conventional breeding. The fundamental advantages of MAS compared to conventional phenotypic selection are: Simpler compared to phenotypic screening. Selection may be carried out at seedling stage.
What is backcross method of breeding?
backcross. A breeding method used to move one or a only a few desirable genes from an agronomically poor crop line to an elite line. This is done by crossing a donor parent to an elite line, and crossing offspring with the ‘desired gene(s)’ back to the elite parent.
What are marker-assisted selection?
This process has been extensively researched and proposed for plant and animal breeding. For example, using MAS to select individuals with disease resistance involves identifying a marker allele that is linked with disease resistance rather than the level of disease resistance.
How is marker-assisted selection used?
Marker-assisted breeding uses DNA markers associated with desirable traits to select a plant or animal for inclusion in a breeding program early in its development. This genetic test is helping breeders to select for hornless cattle, which makes it safer for the animals themselves and the people handling them.
What is the purpose of using an unlinked background marker for selection?
Background markers are markers that are unlinked to the target gene/QTL on all other chromosomes, in other words, markers that can be used to select against the donor genome. This is extremely useful because the RP recovery can be greatly accelerated.
What is the purpose of a backcross?
backcross, the mating of a hybrid organism (offspring of genetically unlike parents) with one of its parents or with an organism genetically similar to the parent. The backcross is useful in genetics studies for isolating (separating out) certain characteristics in a related group of animals or plants.
What are the basic requirements of backcross method?
Requirement of back cross breeding
- Suitable recurrent parent must be available which lacks in one or two characteristics.
- A suitable donor parent must be available, the character must be highly intense.
- Character to be transferred must have high heritability controlled by one or two genes.
How does marker assisted selection work?
How is marker assisted backcrossing used in genetics?
MARKER-ASSISTED backcrossing is routinely applied for gene introgression in plant and animal breeding. Its efficiency depends on the experimental design, most notably on the marker density and position, population size, and selection strategy.
What is the third level of marker assisted breeding?
The third level of MAB involves selecting backcross progeny (that have already been selected for the target trait) with ‘background’ markers. In other words, markers can be used to select against the donor genome, which may accelerate the recovery of the recurrent parent genome. Three levels of selection during marker-assisted backcrossing.
How are DNA markers used in the breeding process?
While there are several applications of DNA markers in breeding, the most promising for cultivar development is called marker assisted selection (MAS). MAS refers to the use of DNA markers that are tightly-linked to target loci as a substitute for or to assist phenotypic screening.
How is backcross breeding used in gene introgression?
BACKCROSSIN G Backcross breeding is a well-known procedure for the introgression of a target gene from a donor line into the genomic background of a recipient line. The objective is to reduce the donor genome content (DGC) of the progenies by repeated back-cross. 5.