Selection is a branch of science devoted to methods of improving existing and creating new breeds of animals and plant varieties.

History of breeding

Initially, up to XVI-XVII centuries was characterized by the selection of artificial selection, when people just selected the best animal breeds and plant varieties.This process was haphazard - a person simply chose to plant the best and large seeds, kept in a herd of the most advanced and prolific animals, etc.

its present development of selection received only during the last century.People began to use the crossing to be combined into a new breed or best grade characteristics of animals or plants.

Genetics - the basis of
selection

The selection is based on the science of genetics.Genetics studies the laws of heredity and variation.With the help of modern genetics, breeders can manage mutations and predict the results of hybridization.It is thanks to the knowledge of genetic laws is now created more than ten thousand varieties of wheat on the basis of a few initial varieties.And that's not all.Many years of breeding work will bring new breeds of chickens, gooseberry varieties, strains of microorganisms capable of producing the desired antibiotics, proteins, etc.

Plant breeding

The modern plant breeding is based on two principles - hybridization and selection.The selection process scientists selected plant varieties with desirable properties, and hybridization - such properties are combined in a single variety.When carrying out hybridization generally used cross-pollination.As a result, there are new hybrids that are in the first generation are more active growth and high yield.This phenomenon is known as heterosis.

Sometimes plant breeding using polyploidy.So is the process when seeds influence of special substances (eg colchicine).As a result of the impact of the number of chromosomes doubles and there are new varieties.

breeding animals

principle selection of animals is different from plant breeding.It also relies on the hybridization and selection.The peculiarities of breeding animals include the presence of a possible sexual reproduction, a small number of individuals in the progeny and a rare change of generations.

Through selection, breeders were able to bring Russia and improve the variety of animal species.Examples of such rocks can serve Kostroma breed of cattle, characterized by high milk yield and the Russian meat-wool breed of sheep.