Question

What do you understand by outcross?

Answer 1

Outcross or outbreeding is an important animal breeding and horticulture technique. This involves a cross between two superior species for their combination in new superior progeny. It is done consecutively for 4 to 6 generations.

Complete answer:
The outcross as the name suggests is cross or breeding between two unrelated species. This is usually done to obtain superior characters of both parents into the new progeny. It is an essential breeding technique used in animal breeding and horticulture practices. Unrelated genetic material is introduced into a breeding line. This is because the parent breeds are very different, having no common ancestors. The benefits of an outcross are that it gives good genetic diversity and reduces the probability of an individual being subjected to genetic abnormalities. It is mostly used in animal breeding. Many of the dogs as pets are examples of cross-breeding. For example, Labradoodles are the result of outcross in Poodle and Labrador dog species.
It is thought that outcrossing is a norm in the wild. In plants, outcross occurs through enforced self-incompatibility. Breeders do outcross to eliminate undesirable traits and enhance and spread superior desirable traits. Outcross allows for the restoration of vigor and size and fertility of a breeding line. The variance of genes can be increased through outcross. The opposite of outcross or outbreeding is inbreeding. It involves a cross between related species. But it leads to inbreeding depression which means a reduction in fertility and variance among individuals.

Note: Outbreeding is now becoming more common and it is being used as an alternative to inbreeding. It is known that the higher the genetic variations in a breeding population, the lower will be the chances for it to suffer inbreeding depression. So, outbreeding provides a solution for inbreeding depression by increasing variations in breeding lines.