Explanation:
Backcross involves crossing the F1 hybrid to either of the parents. It is a type of breeding technique used to transfer a desired trait from one parent to an offspring. The desired trait can be present in one of the parents which is used for backcrossing. This technique is widely used in plant and animal breeding to produce offspring with desirable traits.

Steps involved in backcrossing:

1. Select the parent with the desired trait: The first step in backcrossing is to select the parent with the desired trait. This parent is used as one of the parents in the cross.

2. Cross the F1 hybrid with the selected parent: The F1 hybrid is then crossed with the selected parent to produce the first generation of offspring.

3. Select the offspring with the desired trait: The offspring from the first generation are then screened for the desired trait. The ones with the desired trait are selected for the next round of backcrossing.

4. Repeat the process: The selected offspring are then crossed with the same parent to produce the next generation of offspring. This process is repeated until the offspring have the desired trait and are genetically similar to the parent with the trait.

Applications of backcrossing:

Backcrossing is widely used in plant and animal breeding to produce offspring with desirable traits. Some of the applications of backcrossing are:

1. To introduce disease resistance in plants
2. To introduce desirable traits in domestic animals
3. To improve crop yield
4. To improve the quality of fruits and vegetables.

Conclusion:

Backcrossing is a breeding technique used to transfer a desired trait from one parent to an offspring. It involves crossing the F1 hybrid with either of the parents. This technique is widely used in plant and animal breeding to produce offspring with desirable traits.

Back cross involves crossing the f1 generation with either of two parents fr ex. you have crossed TT×tt in f1 generation you will get all heterozygous tall Tt then if Tt is crossed with TT ie filal generation progeny is crossed with its parentTT its called back cross n if progeny crossed with tt other parent which is double recessive it will be called as test cross.