Breeding is the science of creating new and improving existing breeds. Breeding is the science of creating new breeds of animals. The concept of a breed, variety, strain

Physicists have been aware of quantum effects for more than a hundred years, such as the ability of quanta to disappear in one place and appear in another, or to be in two places at the same time. However, the amazing properties of quantum mechanics are applicable not only in physics, but also in biology.

The best example of quantum biology is photosynthesis: plants and some bacteria use the energy of sunlight to build the molecules they need. It turns out that photosynthesis actually relies on an amazing phenomenon - small masses of energy "learn" all possible ways to apply themselves, and then "choose" the most effective one. Perhaps bird navigation, DNA mutations, and even our sense of smell rely on quantum effects in one way or another. Although this area of ​​science is still very speculative and controversial, scientists believe that once gleaned from quantum biology, ideas can lead to the creation of new drugs and biomimetic systems (biomimetrics is another new scientific field where biological systems and structures are used to create new materials and devices). ).

3. Exometeorology

Jupiter

Along with exo-oceanographers and exogeologists, exometeorologists are interested in studying natural processes occurring on other planets. Now that, thanks to powerful telescopes, it has become possible to study the internal processes on nearby planets and satellites, exometeorologists can monitor their atmospheric and weather conditions. and Saturn, with its incredible size, are prime candidates for exploration, as is Mars, with its regular dust storms.

Exometeorologists even study planets beyond our own. solar system. And interestingly, it is they who can eventually find signs of extraterrestrial life on exoplanets by detecting organic traces in the atmosphere or elevated levels of carbon dioxide - a sign of industrial civilization.

4. Nutrigenomics

Nutrigenomics is the study of the complex relationships between food and genome expression. Scientists working in this field are striving to understand the role of genetic variation and dietary responses in how nutrients affect the genome.

Food really has a huge impact on health - and it all starts at the molecular level, literally. Nutrigenomics works both ways: it studies how our genome influences food preferences, and vice versa. The main purpose of the discipline is to create personalized nutrition - this is necessary to ensure that our food is ideally suited to our unique set of genes.

5. Cliodynamics

Cliodynamics is a discipline that combines historical macrosociology, economic history (cliometrics), mathematical modeling of long-term social processes, and the systematization and analysis of historical data.

The name comes from the name of the Greek muse of history and poetry Clio. Simply put, cliodynamics is an attempt to predict and describe the broad social connections of history - both to study the past and as a potential way to predict the future, for example, to predict social unrest.

6. Synthetic biology

Synthetic biology is the design and construction of new biological parts, devices, and systems. It also includes upgrading existing biological systems for an infinite number of useful applications.

Craig Venter, one of the leading experts in this field, stated in 2008 that he had recreated the entire genome of a bacterium by gluing together its chemical components. Two years later, his team created "synthetic life" - DNA molecules created with a digital code and then 3D printed and inserted into a living bacterium.

In the future, biologists intend to analyze various types of genome to create useful organisms for introduction into the body and biorobots that can produce chemical substances- biofuel - from scratch. There is also the idea of ​​creating pollution-fighting artificial bacteria or vaccines to treat serious illnesses. The potential of this scientific discipline is simply enormous.

7. Recombinant memetics

This field of science is just emerging, but it is already clear that it is only a matter of time - sooner or later scientists will gain a better understanding of the entire human noosphere (the totality of all known to people information) and how the dissemination of information affects virtually every aspect of human life.

Like recombinant DNA, where different genetic sequences come together to create something new, recombinant memetics studies how - ideas passed from person to person - can be adjusted and combined with other memes and memeplexes - well-established complexes of interconnected memes. This can be useful for "social therapeutic" purposes, such as combating the spread of radical and extremist ideologies.

8. Computational sociology

Like cliodynamics, computational sociology deals with the study of social phenomena and trends. Central to this discipline is the use of computers and related information processing technologies. Of course, this discipline only developed with the advent of computers and the ubiquity of the Internet.

Particular attention in this discipline is given to the huge flows of information from our daily lives, for example, letters to e-mail, phone calls, social media posts, credit card purchases, search engine queries, and so on. Examples of work can serve as a study of the structure social networks and how information spreads through them, or how intimate relationships arise on the Internet.

9. Cognitive economics

As a rule, economics is not associated with traditional scientific disciplines, but this may change due to the close interaction of all scientific branches. This discipline is often confused with behavioral economics (the study of our behavior in the context of economic decisions). Cognitive economics is the science of how we think. Lee Caldwell, a blogger about the discipline, writes about it:

“Cognitive (or financial) economics… pays attention to what actually happens in a person’s mind when he makes a choice. What is the internal structure of decision-making, what influences it, what information is perceived by the mind at this moment and how is it processed, what are the internal forms of preference for a person, and, ultimately, how all these processes are reflected in behavior?

In other words, scientists start their research at a lower, simplified level, and form micromodels of decision principles to develop a model of large-scale economic behavior. Often this scientific discipline interacts with related fields, such as computational economics or cognitive science.

10. Plastic electronics

Typically, electronics is associated with inert and inorganic conductors and semiconductors such as copper and silicon. But the new branch of electronics uses conductive polymers and conductive small molecules based on carbon. Organic electronics includes the development, synthesis and processing of functional organic and inorganic materials along with the development of advanced micro- and nanotechnologies.

In truth, this is not such a new branch of science, the first developments were made back in the 1970s. However, it was only recently that it was possible to bring all the accumulated data together, in particular, due to the nanotechnological revolution. Thanks to organic electronics, we may soon have organic solar panels, self-organizing monolayers in electronic devices and organic prostheses, which in the future will be able to replace damaged human limbs: in the future, the so-called cyborgs, it is quite possible, will consist more of organic matter than of synthetic parts.

11 Computational Biology

If you like mathematics and biology equally, then this discipline is just for you. Computational biology seeks to understand biological processes through the language of mathematics. This is equally used for other quantitative systems, such as physics and computer science. Scientists from the University of Ottawa explain how this was possible:

“With the development of biological instrumentation and easy access to computing power, biology as such has to operate with an increasing amount of data, and the speed of the knowledge gained is only growing. Thus, making sense of the data now requires a computational approach. At the same time, from the point of view of physicists and mathematicians, biology has grown to a level where theoretical models of biological mechanisms can be tested experimentally. This led to the development of computational biology.”

Scientists working in this field analyze and measure everything from molecules to ecosystems.

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Selection (lat. selectio - choose) - the science of creating new and improving existing breeds animals, plant varieties, strains of microorganisms. Selection is also called the industry Agriculture engaged in breeding new varieties and hybrids of agricultural crops and animal breeds

breed - in fruit growing, a set of genera and species of useful food plants that have certain similar characteristics.

Variety (English cultivar) - group cultivated plants, obtained as a result of selection within the lowest known botanical taxa and possessing a certain set of characteristics (useful or ornamental) that distinguishes this group of plants from other plants of the same species.

Strain (from German Stamm, literally - "trunk", "basis") - a pure culture of viruses, bacteria, other microorganisms or cell culture, isolated at a certain time and in a certain place. Since many microorganisms reproduce by mitosis (division), without the participation of the sexual process, in essence, the species of such microorganisms consist of clonal lines that are genetically and morphologically identical to the original cell. A strain is not a taxonomic category, the lowest taxon in all organisms is a species, the same strain cannot be isolated a second time from the same source at another time.

The assignment of a microorganism to a particular species occurs on the basis of fairly broad features, such as the type of nucleic acid and the structure of the capsid in viruses; the ability to grow on certain hydrocarbons and the type of metabolic products produced, as well as conserved genome sequences in bacteria. Within species, there are variations in the size and shape of plaques (negative "colonies" of the virus) or colonies of the microorganism, the level of enzyme production, the presence of plasmids, virulence, etc.

There is no universally recognized nomenclature for the names of strains in the world, and the names used are rather arbitrary. As a rule, they consist of individual letters and numbers, which are written after the species name. For example, one of the most famous strains of Escherichia coli.

Selection and types of crossing

The selection of parental forms and types of crossing of animals are carried out taking into account the goal set by the breeder. This can be a purposeful obtaining of a certain exterior, an increase in milk production, milk fat content, meat quality, etc. Breeding animals are evaluated not only by external signs, but also by the origin and quality of offspring. Therefore, it is necessary to know their pedigree well. In breeding farms, when selecting producers, a record of pedigrees is always kept, in which the exterior features and productivity of parental forms are evaluated over a number of generations. According to the traits of the ancestors, especially on the maternal line, one can judge with a certain probability about the genotype of the producers.

In breeding work with animals, two methods of crossing are mainly used: outbreeding and inbreeding.

Outbreeding, or unrelated crossing between individuals of the same breed or different breeds of animals, with further strict selection, leads to the maintenance of useful qualities and to their strengthening in the next generations.

When inbreeding, brothers and sisters or parents and offspring (father-daughter, mother-son, cousins, etc.) are used as initial forms. Such crossing is to a certain extent similar to self-pollination in plants, which also leads to an increase in homozygosity and, as a result, to the consolidation of economically valuable traits in the offspring. At the same time, homozygotization for the genes that control the studied trait occurs the faster, the more inbreeding used in inbreeding. However, homozygotization during inbreeding, as in the case of plants, leads to the weakening of animals, reduces their resistance to environmental influences, and increases the incidence. To avoid this, it is necessary to carry out a strict selection of individuals with valuable economic traits.

In breeding, inbreeding is usually only one step in improving a breed. This is followed by crossing different interline hybrids, as a result of which unwanted recessive alleles are transferred to a heterozygous state and the harmful effects of inbreeding are markedly reduced.

In domestic animals, as in plants, the phenomenon of heterosis is observed: during interbreeding or interspecific crosses, hybrids of the first generation experience especially powerful development and an increase in viability. A classic example of the manifestation of heterosis is the mule - a hybrid of a mare and a donkey. This is a strong, hardy animal that can be used in much more difficult conditions than the parental forms.

Heterosis is widely used in industrial poultry farming (for example, broiler chickens) and pig breeding, since the first generation of hybrids is directly used for economic purposes.

distant hybridization. Distant hybridization of domestic animals is less efficient than that of plants. Interspecific hybrids of animals are often sterile. At the same time, the restoration of fertility in animals is a more difficult task, since it is impossible to obtain polyploids based on the multiplication of the number of chromosomes in them. True, in some cases, distant hybridization is accompanied by normal fusion of gametes, normal meiosis and further development of the embryo, which made it possible to obtain some breeds that combine valuable features of both species used in hybridization. For example, in Kazakhstan, based on the hybridization of fine-fleeced sheep with wild mountain sheep argali, a new breed of fine-fleeced argali merinos has been created, which, like argali, graze on high mountain pastures that are inaccessible to fine-fleeced merinos. Improved breeds of local cattle.

Achievements of Russian and Belarusian livestock breeders

Breeders in Russia have achieved significant success in creating new and improving existing breeds of animals. Thus, the Kostroma breed of cattle is distinguished by high milk productivity - more than 10 thousand kg of milk per year. The Siberian type of the Russian meat and wool breed of sheep is characterized by high meat and wool productivity. The average weight of breeding rams is 110-130 kg, and the average wool shear in pure fiber is 6-8 kg. There are also great achievements in the selection of pigs, horses, chickens and many other animals.

As a result of a long and purposeful selection and breeding work, scientists and practitioners of Belarus have bred a black-and-white type of cattle. Cows of this breed in good feeding and keeping conditions provide milk yields of 4-5 thousand kg of milk with a fat content of 3.6-3.8% per year. The genetic potential of the milk productivity of the Black-and-White breed is 6.0-7.5 thousand kg of milk per lactation. There are about 300 thousand heads of this type of cattle in Belarusian farms.

Breeds of Belarusian black-and-white and large white pigs were created by specialists of the breeding center of the Scientific Research Institute of Animal Husbandry. Such breeds of pigs are distinguished by the fact that animals reach a live weight of 100 kg in 178-182 days on control fattening with an average daily gain of over 700 g, and the offspring is 9-12 piglets per farrowing.

Various crosses of chickens (for example, Belarus-9) are characterized by high egg production: for 72 weeks of life - 239-269 eggs with an average weight of each 60 g, which corresponds to the indicators of highly productive crosses at international competitions.

Breeding work continues to enlarge, increase the precocity and working capacity of the horses of the Belarusian draft group, improve the productive potential of sheep in terms of wool shearing, live weight and fertility, to create lines and crosses of meat ducks, geese, a highly productive breed of carp, etc.

To successfully solve the problems facing selection, Academician N.I. Vavilov emphasized the importance of studying the varietal, species, and generic diversity of crops; study hereditary variability; the influence of the environment on the development of traits of interest to the breeder; knowledge of the patterns of inheritance of traits during hybridization; features of the selection process for self- or cross-pollinators; artificial selection strategies.

Each animal breed, plant variety, strain of microorganisms is adapted to certain conditions, therefore, in each zone of our country there are specialized variety testing stations and breeding farms for comparing and testing new varieties and breeds. For successful work the breeder needs varietal diversity of the source material. At the All-Union Institute of Plant Industry N.I. Vavilov collected a collection of varieties of cultivated plants and their wild ancestors from all over the globe, which is currently being replenished and is the basis for breeding any crop.

Centers of origin Location Cultivated plants 1. South Asian tropical Tropical India, Indochina, Southeast Asian islands Rice, sugar cane, citrus, eggplant, etc. (50% of cultivated plants) 2. East Asian Central and East China, Japan, Korea, Taiwan Soybean, millet, buckwheat, fruit and vegetable crops plum, cherry, etc. (20% of cultivated plants) 3. Southwest Asian Asia Minor, Central Asia, Iran, Afghanistan, Southwest India Wheat, rye, legumes, flax , hemp, turnip, garlic, grapes, etc. (14% of cultivated plants) 4. Mediterranean Countries along the shores of the Mediterranean Sea Cabbage, sugar beet, olives, clover (11% of cultivated plants) 5. Abyssinian Abyssinian Highlands of Africa Durum wheat, barley, bananas, coffee tree, sorghum 6. Central American South Mexico Corn, cocoa, pumpkin, tobacco, cotton 7. South American West Coast of South America Potato, pineapple, cinchona

Mass selection is used in the selection of cross-pollinated plants (rye, corn, sunflower). In this case, the variety is a population of heterozygous individuals, and each seed has a unique genotype. With the help of mass selection, varietal qualities are preserved and improved, but the selection results are unstable due to random cross-pollination.

Individual selection is used in the selection of self-pollinated plants (wheat, barley, peas). In this case, the offspring retains the characteristics of the parental form, is homozygous and is called a pure line. Pure line A pure line is the offspring of one homozygous self-pollinated individual. Since mutation processes are constantly occurring, there are practically no absolutely homozygous individuals in nature. Mutations are most often recessive. Under the control of natural and artificial selection, they fall only when they pass into the homozygous state.

This type of selection plays a decisive role in selection. A complex of factors acts on any plant during its life. environment, and it must be resistant to pests and diseases, adapted to a certain temperature and water regime.

This is called inbreeding. Inbreeding occurs during self-pollination of cross-pollinated plants. For inbreeding, plants are selected whose hybrids give the maximum effect of heterosis. Such selected plants undergo forced self-pollination for a number of years. As a result of inbreeding, many unfavorable recessive genes go into a homozygous state, which leads to a decrease in plant viability, to their "depression". Then the resulting lines are crossed with each other, hybrid seeds are formed, giving a heterotic generation.

This is a phenomenon in which hybrids surpass parental forms in a number of characteristics and properties. Heterosis is typical for hybrids of the first generation, the first hybrid generation gives an increase in yield up to 30%. In subsequent generations, its effect weakens and disappears. The effect of heterosis is explained by two main hypotheses. The dominance hypothesis suggests that the effect of heterosis depends on the number of dominant genes in the homozygous or heterozygous state. The more genes in the genotype in the dominant state, the greater the effect of heterosis. P AAbbCCdd×aaBBccDD F 1 AaBbCcDd

The hypothesis of overdominance explains the phenomenon of heterosis by the effect of overdominance. Overdominance Overdominance is a type of interaction of allelic genes, in which heterozygotes are superior in their characteristics (in weight and productivity) to the corresponding homozygotes. Starting from the second generation, heterosis fades, as part of the genes passes into the homozygous state. Aa × Aa AA 2Aa aa

It makes it possible to combine the properties of different varieties. For example, when breeding wheat, proceed as follows. Anthers are removed from the flowers of a plant of one variety, a plant of another variety is placed next to it in a vessel with water, and plants of two varieties are covered with a common insulator. As a result, hybrid seeds are obtained that combine the traits of different varieties that the breeder needs.

Polyploid plants have a larger mass of vegetative organs, larger fruits and seeds. Many crops are natural polyploids: wheat, potatoes, varieties of polyploid buckwheat, sugar beets have been bred. Species in which the same genome is multiply multiplied are called autopolyploids. The classic method for obtaining polyploids is the treatment of seedlings with colchicine. This substance blocks the formation of spindle microtubules during mitosis, the set of chromosomes doubles in the cells, and the cells become tetraploid.

The technique for overcoming infertility in distant hybrids was developed in 1924 by the Soviet scientist G.D. Karpechenko. He acted as follows. First I crossed radish (2n = 18) and cabbage (2n = 18). The diploid set of the hybrid was equal to 18 chromosomes, of which 9 chromosomes were "rare" and 9 "cabbage". The resulting cabbage-rare hybrid was sterile, since during meiosis the "rare" and "cabbage" chromosomes were not conjugated.

Further, with the help of colchicine G.D. Karpechenko doubled the chromosome set of the hybrid, the polyploid began to have 36 chromosomes, during meiosis "rare" (9 + 9) chromosomes conjugated with "rare", "cabbage" (9 + 9) with "cabbage". Fertility has been restored. In this way, wheat-rye hybrids (triticale), wheat-couch grass hybrids, etc. were obtained. Species that combine different genomes in one organism, and then multiply them, are called allopolyploids.

Somatic mutations are used to select vegetatively propagating plants. This was used in his work by I.V. Michurin. By vegetative propagation, a beneficial somatic mutation can be maintained. In addition, only with the help of vegetative propagation, the properties of many varieties of fruit and berry crops are preserved.

It is based on the discovery of the impact of various radiations to obtain mutations and on the use of chemical mutagens. Mutagens allow you to get a wide range of different mutations. Now more than a thousand varieties have been created in the world, leading a pedigree from individual mutant plants obtained after exposure to mutagens.

The mentor's method With the help of the mentor's method I.V. Michurin sought to change the properties of the hybrid in the right direction. For example, if it was necessary to improve the taste of a hybrid, cuttings from a parent organism that had good taste were grafted into its crown, or a hybrid plant was grafted onto a rootstock, in the direction of which it was necessary to change the quality of the hybrid. I.V. Michurin pointed to the possibility of controlling the dominance of certain traits during the development of a hybrid. For this, in the early stages of development, it is necessary to influence certain external factors. For example, if hybrids are grown in open ground, their frost resistance increases on poor soils.

Selection - the science of creating new and improving existing plant varieties, animal breeds and strains of microorganisms. The scientific foundations of selection were laid by Charles Darwin in his work On the Origin of Species (1859), where he highlighted the causes and nature of the variability of organisms and showed the role of selection in the creation of new forms. An important milestone further development selection was the discovery of the laws of heredity. A great contribution to the development of selection was made by M. I. Vavilov, author of the law of homological series in hereditary variability and the theory of the centers of origin of cultivated plants.

The subject of selection is the study, under conditions created by man, of the patterns of change, development, and transformation of plants, animals, and microorganisms. With the help of selection, methods of influencing cultivated plants and domestic animals are being developed. This happens in order to change their hereditary qualities in the direction necessary for a person. Selection has become one of the forms of evolution of the plant and animal world. It is subject to the same laws as the evolution of species in nature, but natural selection is partially replaced by artificial selection.

Theoretical basis of selection is genetics, evolutionary doctrine. Using evolutionary theory, the laws of heredity and variability, the doctrine of pure lines and mutation, breeders have developed various methods breeding plant varieties, animal breeds and strains of microorganisms. The main selection methods are selection, hybridization, polyploidy, experimental mutagenesis, genetic engineering methods, etc.

The main tasks of modern breeding is to increase the productivity of varieties and breeds, transfer them to an industrial basis, create breeds, varieties and strains adapted to the conditions of modern agriculture, ensure full production food products at the lowest cost, etc.

Breeding is divided into three main sections: plant breeding, animal breeding and microbial breeding.

The concept of the breed, variety, strain

The objects and end result of the selection process are breeds, varieties and strains.

animal breed is the totality of individuals within a certain kind animals, as if it has genetically determined stable characteristics (properties and signs) , which distinguish it from other sets of individuals of this species of animals, steadily pass them on to their descendants and is the result of human intellectual activity. Animals of the same breed are similar in body type, productivity, fertility, color. This allows them to be distinguished from such other breeds. There must be a sufficient number of animals in the breed, otherwise the possibility of applying selection is limited, quickly leads to forced inbreeding and, as a result, to the degeneration of the breed. In addition to high productivity and numbers, the breed should be fairly common. This increases the possibilities for creating different types in it, which contributes to its further improvement. Natural and geographical conditions have a great influence on the formation of rock features - features of soils, plants, climate, terrain, and the like. When animals are brought into new natural and climatic conditions, physiological changes occur in their bodies, and in some cases they are deep, in others - storey ones. The restructuring of the body systems is the deeper, the greater the difference between the new and previous conditions of existence. The process of adaptation of animals to new conditions of existence is called acclimatization, it can last several generations.

plant variety - a group of cultivated plants that, as a result of selection, have received a certain set of characteristics (useful or decorative) , which distinguish this group of plants from other plants of the same species. Each variety of plants has a unique name and retains its properties with repeated cultivation.

Microorganism strain - pure culture of a certain type of microorganisms, morphological physiological features which are well studied. Strains can be isolated from various sources (soil, water, food) or from one source in different time. Therefore, the same type of bacteria, yeast, microscopic fungi can have a large number of strains that differ in a number of properties, such as sensitivity to antibiotics, the ability to form toxins, enzymes, and other factors. Strains of microorganisms that are used in industry for the microbiological synthesis of proteins (in particular, enzymes), antibiotics, vitamins, organic acids, etc., are much more productive (as a result of selection) than wild strains.

Breeds, varieties, strains are not able to exist without constant attention person. For each variety, breed, strain is characteristic specific response to environmental conditions. This means that their positive traits can manifest themselves only at a certain intensity of environmental factors. Scientists in scientific and practical institutions comprehensively investigate the properties of new breeds and varieties and check their suitability for use in a certain climatic zone, that is, they carry out their zoning. zoning research - a set of measures aimed at checking the conformity of the qualities of certain breeds or varieties to the conditions of a certain natural area, That is necessary condition their rational use on the territory of any country. The best for use in a certain climatic zone are regionalized varieties, breeds, the positive properties of which can manifest themselves only under certain conditions.

Breeding is the science of creating new breeds of animals, plant varieties, strains of microorganisms. Breeding is also called the branch of agriculture engaged in the development of new varieties and hybrids of crops and animal breeds. Selection and seed production of winter wheat in Siberia.

Plant breeding Methods of plant breeding. The main methods of plant breeding are selection and hybridization. However, it is impossible to obtain forms with new features and properties by the selection method; it only allows one to isolate genotypes already present in the population. To enrich the gene pool of the created plant variety and obtain optimal combinations of traits, hybridization is used with subsequent selection. In breeding, two main types of artificial selection are distinguished: mass and individual. plant mutation breeding

Mass and individual selection Mass selection is the selection of a group of individuals that are similar in one or a set of desired traits, without checking their genotype. For example, from the entire population of cereals of one variety or another, only those plants are left for further reproduction that are resistant to pathogens and lodging, have a large ear with a large number of spikelets, etc. When they are re-sown, plants with necessary qualities. The variety obtained in this way is genetically homogeneous, and the selection is periodically repeated. With individual selection (by genotype), the offspring of each individual plant in a number of generations is obtained and evaluated with mandatory control of the inheritance of traits of interest to the breeder. As a result of individual selection, the number of homozygotes increases, i.e., the resulting generation becomes genetically homogeneous. Such selection is usually used among self-pollinated plants (wheat, barley, etc.) to obtain pure lines. A pure line is a group of plants that are descendants of one homozygous self-pollinated individual. They have the highest degree of homozygosity and represent a very valuable source material for selection.

Animal breeding Features of animal breeding. The basic principles of animal breeding are no different from the principles of plant breeding. However, the selection of animals has some features: they are characterized only by sexual reproduction; mostly very rare alternation of generations (in most animals after a few years); the number of individuals in the offspring is small. Therefore, in breeding work with animals, the analysis of the totality of external signs, or exterior, characteristic of a particular breed.

Selection of goldfish and parrots By selection, a veiled form was obtained. Professional experience in breeding and selection of 27 years.

Selection of microorganisms Microorganisms (bacteria, microscopic fungi, protozoa, etc.) play an extremely important role in the biosphere and economic activity person. Of the more than 100 thousand species of microorganisms known in nature, several hundred are used by man, and this number is growing. A qualitative leap in their use has taken place in recent decades, when many genetic mechanisms for the regulation of biochemical processes in microorganism cells have been established. The selection of microorganisms (unlike the selection of plants and animals) has a number of features: 1) the breeder has an unlimited amount of material for work: billions of cells can be grown in Petri dishes or test tubes on nutrient media in a matter of days; 2) more efficient use of the mutation process, since the genome of microorganisms is haploid, which makes it possible to detect any mutations already in the first generation; 3) the simplicity of the genetic organization of bacteria: a significantly smaller number of genes, their genetic regulation is simpler, gene interactions are simple or absent.