Backcross-Advantages-Applications
Backcross breeding method has certain advantages and applications. Some of them are listed below.
Advantages of Back Cross Method
Merits of back cross method are given here.
- Gives predicted results. Extensive tests are not necessary as recurrent parent is usually a well established variety
- We can obtain same results again and again
- While eliminating defects of well established variety there is no much change in its adaptability, performance and genotypic background
- Only method for interspecific gene transfer.
- Independent of environment
- This method offers considerable control over the genetic variation in the segregating population under consideration
- Little record keeping
- Requires small populations
- Backcrossing is applicable for both – dominant gene transfer and recessive gene transfer.
Disadvantages of Back Cross Method
Demerits of back cross method are given here.
- Newly developed variety is superior to the recurrent parent only for the character which is transferred, not for others.
- Ineffective for traits with low heritability means quantitative traits.
- If undesirable genes are closely linked to the desired gene, the undesirable genes are probably transferred along with the desired gene to the new variety.
- Little recombination
- Its lengthy process, by the time we transfer a gene to the variety, that variety may have been replaced by other superior varieties.
Applications of Back Cross Method
Applications of back cross method are given here.
- Intervarietal transfer of qualitative characters and quantitative characters with high heritability.
- Interspecific transfer of traits with high heritability.
- To improve well established variety with respect to one or few characters.
- Isogenic lines production
- Cytoplasm transfer esp. with cytoplasmic male sterility (CMS) involved, used to transfer male sterility into purelines, which is a prerequisite for many hybrid production breeding programs.
- Production of transgressive segregants is possible by modification of the method.
