plant breeding is called the science of creating a qualitatively new and improvement of existing cultivars.The basis of selection are its main methods - selection and hybridization.The theoretical basis of selection - the science of genetics.Features
plant breeding due to successfully meet the challenges that it faces.A very significant study of high-quality, genera and species diversity of cultures, environmental influences on the development of the main features, laws of inheritance of characteristics for hybridization, as well as the features of the process of selection and artificial selection strategy.
Each variety of plants adapted to any particular conditions, and therefore in different areas there are different specialized stations and breeding farms to test and compare new varieties of plants.
to plant breeding has been successful, the breeder should have varietal diversity of the starting material.Academic NIVavilov once gathered a huge collection of varieties of plants and their ancestors from all over the planet Earth, which is now successfully updated and is considered the basis for the work on the selection of any culture.
Vavilov identified seven centers of origin of crops: tropical South Asian, East Asian, Mediterranean, South-West Asian, Abyssinian, South American, Central American.The richest region in the number of cultures - the ancient centers of civilization.In such places, the earliest farming standards, respectively, and plant breeding and artificial selection carried out over a long period of time.Let us consider in more detail what is this concept presents.
There are certain methods of plant breeding: the selection and hybridization.Tackling turn can be an individual and mass.
mass selection is called a form of artificial selection, which is used in the selection of so-called "cross-pollinated" plants (rye, corn, sunflower).In this case, the Class is a population that consists of heterozygous individuals, where each seed carries a unique genotype.Thanks to a massive selection of preserved and improved varietal characteristics, but the results of this selection is very unstable due to the uncertainty of cross-pollination.
individual selection is used in plant breeding, are pollinated by yourself (barley, wheat).Progeny retains all, without exception, the parent signs the form and is called pure lines (so-called self-pollinated progeny of a single homozygous individuals).Since mutational processes occur constantly, in fact, homozygous individuals are extremely rare.Under the control of artificial and natural selection they fall only after the transition in a homozygous state.
Plant breeding method natural selection plays a very important role.Any plant throughout its life under the influence of certain external factors, so it must be resistant to diseases and pests, and adapted to the water temperature.
Inbreeding - inbreeding.This phenomenon occurs in cross-pollinated plants by self-pollination.For this method of selection chosen such plants, hybrids which are able to give the maximum effect of heterosis.Such plants are subject to many years of forced self-pollination.
There is also a method such as remote hybridization.So called crossbreeding of plants that belong to different species.As a rule, distant hybrids are sterile, so the gametes are formed.
Plant breeding has also methods such as the use of somatic mutations, experimental mutagenesis and selection methods proposed JVMichurin.These and other methods you can learn more by reading the work of these scientists.
