Michurin developed a method of breeding work. Classification of I.V.

Vegetative propagation is in one way or another characteristic of many plants, but the group of vegetatively propagated plants usually includes only those plants for which this form of propagation is the main one.

Vegetatively propagated plants include: potatoes, onions, garlic, almost all fruit trees and berry bushes, most flower and ornamental perennials, etc. In all these plants, the varieties are essentially nothing more than a group of plants derived from one original vegetatively propagated plant. Such varieties are called clone varieties and even just clones (the Greek word “clone” in Russian means “branch”). Our famous researcher on the genetics of vegetatively propagated plants, TV Asseeva, wrote in 1929; "Among our cultivated plants there are a number of those that under normal economic conditions do not reproduce sexually ... what such plants call a variety is, in essence, only a collection of countless independently existing branches of one initial specimen."

All the characteristic features of the selection of vegetatively propagated plants are determined by the specific properties of the clone varieties. Indeed, when breeding new varieties from vegetatively propagated plants, the task is not to create a population or a pure line that steadfastly transfer its positive properties to seed offspring, but to obtain a separate plant that has economically valuable properties that are interesting for the breeder. If such a plant can be obtained, then its positive properties are easily fixed by obtaining vegetative offspring, which gives rise to a new clone variety. The instability of sexual offspring in such a variety is of little interest to the breeder, since the variety is reproduced vegetatively.

The breeding of vegetatively propagated plants has two main ways: 1) the creation of new clone varieties by selection in a variegated source material, which is a mixture of a number of different clones (local varieties and varieties or hybrid families), and 2) breeding new varieties by improving old varieties - clones by selecting economically valuable mutations.

In vegetatively propagated plants, complex vegetative, often sterile interspecific hybrids, triploids and plants with other chromosomal deviations from the norm, plants with double flowers, parthenocarpic (i.e. seedless) plants, etc., can be isolated and fixed as new varieties.

In this regard, such techniques as distant hybridization, experimental production of polyploids, and artificial induction of other mutations in vegetatively propagated plants are of particular importance.

Let us now turn to an examination of the main forms of selection in vegetatively propagated plants.

A) Direct use of the variety of forms that exist in nature and culture.

This primitive form of selection is widely used in the initial introduction of new vegetatively propagated plants into culture, as well as in the first stages of selection aimed at improving commercial varieties that are a variegated mixture of different clones. In this way, a number of new varieties were obtained for apple, plum, apricot, peach, citrus, onion, garlic and other plants. Particularly interesting results were obtained in the study of world collections collected by the All-Union Institute of Plant Industry, from which it was possible to isolate a number of valuable varieties that are widely used in production. But in forms that have already undergone thorough breeding study, the selection of new varieties is unlikely.

B) Obtaining new varieties by sowing seeds from free pollination.

This form of selection has given rise to very many widespread varieties of vegetatively propagated plants. For example, the famous Burbank Seedling potato, which at one time was the most popular in the United States, was obtained in this way (Burbank, 1955).

Most of the old varieties of fruit trees probably also originated from selective seedlings grown from seeds formed in the fruit as a result of free pollination.

The first Russian breeder A. T. Bolotov obtained all the varieties of apple trees bred by selecting the best seedlings obtained from seeds that arose as a result of free pollination. But Bolotov already clearly understood the significance of the paternal parental form for the quality of seedlings. He paid great attention to the varieties surrounding the tree on which the seeds arose, giving rise to seedlings. These varieties could participate in the pollination of the flowers of a neighboring tree (Bolotov, 1952).

IV Michurin at the beginning of his activity quite widely practiced sowing seeds isolated from fruits that developed from free pollination. Based on his personal experience, he came to the conclusion that all varieties of fruit and berry plants can be divided into three groups. Some, under any conditions, poorly transmit their positive qualities to the family offspring that arise during free pollination. Others produce high quality offspring with free pollination only when there are no wild varieties of the same species blooming at the same time nearby. And finally, the third give good offspring from free pollination under any conditions.

However, IV Michurin considers it inexpedient to use seeds obtained from free pollination in breeding, even if the variety produces high-quality seedlings of the cultivated type with free pollination. The fact is that in breeding, the main task is usually not to obtain a plant in general with a cultivated appearance and edible fruits, but to obtain plants with completely definite combinations of economically valuable traits, previously outlined by the breeder.

C) The use of hybrids obtained by artificial crossing of different varieties.

Since sexual reproduction ceases to play a decisive role in the preservation of vegetatively propagated forms during the struggle for existence, they often have a significant reduction in sexual reproduction, various recessive lethal and semi-lethal hereditary factors accumulate, and complex heterozygosity arises. In intervariety crosses of vegetatively propagated plants, the first hybrid generation is usually very heterogeneous, and complex splitting is observed in it along a number of economically valuable traits. Therefore, when crossing varieties and varieties of vegetatively propagated plants, it is impossible to predict in advance what the appearance of the hybrids and their hereditary structure will be. Most often, such hybrids vary greatly according to the most important economic characteristics and are good material for selection. For many vegetatively propagated plants, obtaining hybrids between varieties with complementary economically valuable properties and selection in the first generation of hybrids is the main form of selection.

Many of the best potato varieties are obtained by selection in the split first generation obtained from intervarietal crosses. An example of such varieties is the widespread variety Lorkh, selected by A.G. Lorkh when crossing the varieties Epicurus with Alma, and many others.

A number of other vegetatively propagated plants have approximately the same picture. However, in the first generation, it is not always possible to find plants with a combination of economically valuable traits desirable for the breeder, and then one has to resort to selection in the next generations of hybrids.

D) The use of hybrids of the next generations, obtained either by self-pollination, or by crossing with one of the original forms or other varieties.

The variety of forms in the first generation depends on a variety of combinations of traits determined by hereditary factors for which the original forms are heterozygous. However, the most important traits for the breeder are often associated with hereditary factors that are homozygous in the original forms. According to such characteristics, splitting is absent in the first generation. If the breeder is not satisfied with the combination of traits observed in the first generation, then it is necessary to resort to obtaining the next hybrid generations. The most natural way to obtain them is self-pollination of plants in the first generation or crossing them with each other, that is, getting the usual second generation. In some vegetatively propagated plants, this route has been quite widely used.

Thus, one of the most famous potato varieties, Early Rose, was obtained by self-pollination of the hybrid Chilean pomegranate variety. Several other widespread potato varieties are also self-pollinated and first-generation hybrid crosses. But this form of selection is fraught with the danger of the onset and accumulation of depression, which is usually observed during inzukhta. This danger for vegetatively propagated plants is especially great, since they have especially favorable conditions for the accumulation of recessive lethal and semi-lethal mutations. These mutations, passing into a homozygous state during inzuchta, can easily cause a sharp weakening of plants in the offspring.

This phenomenon can be quite clearly demonstrated by the example of potato breeding. The homeland of the potato is Central and South America, where there is a wide variety of wild and cultivated species, varieties and varieties of potatoes. Potatoes were introduced to Europe in the 16th century in a relatively small number of samples, which served as the starting material for the work of the first potato breeders. As a result, at the beginning of the 19th century, all European potato varieties turned out to be morphologically very uniform and had a sharply reduced resistance to various diseases and a reduced ability for sexual reproduction.

In 1842, an epidemic of potato rot broke out, engulfing all of Europe and North America. At one time it seemed that this disease would nullify the entire potato crop. And only as a result of the heroic efforts of two breeders - Goodrich in the USA and Paterson in Scotland, who widely used a number of varieties and varieties obtained from Central and South America in their breeding work, it was possible to obtain new varieties resistant to potato rot, and thereby save potato culture.

However, many modern potato varieties are nevertheless closely related to each other and, when crossed, give a rather similar offspring, of little interest from an economic point of view and often showing more or less pronounced depression. These negative consequences of blood cultivation had an especially strong effect on potato breeding in the USA, where, due to the peculiar requirements of the market, which highly appreciated the characteristic features of the Early Rose variety, all varieties and forms not related in their origin to the Early Rose were simply thrown out of the culture as non-standard, not meeting market requirements. As a result, the hereditary diversity (gene pool) of modern American potato varieties has become very narrow. It became very difficult to get something outstanding, since almost all practically valuable combinations have already been realized within the existing complex of genes. All this led to a kind of crisis in potato breeding in the United States. Phenomena of the same order also take place in the countries of Western Europe.

AP Gern (1934) writes the following about this: “The consequences of the loss of most of the gene pool for Europe will be the same as for America. In the presence of a close relationship between modern potato varieties, it becomes more and more difficult to find such combinations of traits that would not repeat the existing ones and would surpass them in a number of points. In Europe, the difference in national tastes and the wider national economic use of potatoes so far ensures the preservation of somewhat greater genetic diversity than is the case in America, but still this base is close to its exhaustion. " To overcome these difficulties, breeders who worked with potatoes began, during intervarietal hybridization, to cross varieties of different origins that did not have common ancestors. But within the varieties of the United States and Europe, which are closely related to each other, the selection of such combinations was very difficult.

In this regard, the discovery by expeditions of the All-Union Institute of Plant Growing of a huge variety of cultivated and wild forms of potatoes in Mexico and Central and South America and their involvement in the field of breeders' activities aroused keen interest and made a kind of revolution in potato breeding (Veselovsky, 1934; Yuzepchuk and Bukasov, 1929; Broili, 1921; Müller, 1935).

Thus, the largest English breeder and expert on potatoes, R. N. Salaman, back in 1943, in his article "Latest research on potato breeding" (Salaman, 1943), clearly raised the question of the great importance of new forms found by expeditions of the All-Union Institute of Plant Industry for the creation of new varieties of potatoes and wrote that the potato now "has become promising in the sense of the possibility of creating forms that meet the most diverse requirements."

RN Salaman noted that the main task of potato breeding when crossing old cultivated varieties with newly discovered forms is to create varieties that are immune to diseases and pests, having at the same time increased productivity and increased starch content.

Soviet breeders in the 20s and 30s widely launched work on interspecific hybridization of potatoes. At a number of stations, tens and hundreds of thousands of seedlings obtained by distant hybridization were grown. Despite a number of difficulties associated with the presence of a number of negative "savage" traits in hybrids of the first generation and with a sharp weakening in hybrids of subsequent generations of such positive traits as frost resistance and resistance to a number of fungal diseases, in this way it was possible to obtain a number of seedlings that showed great promise and to develop several new varieties resistant to late blight and some other potato diseases.

However, even in those years, there were voices from the followers of T. D. Lysenko who objected to the widespread use of distant hybridization and suggested replacing it with vegetative hybridization and directed education of hybrid seedlings (Maksimovich, 1940). These breeders pointed out that many of the promising seedlings obtained by distant hybridization, during vegetative propagation, quickly lose their positive qualities, and believed that directed education can prevent the deterioration of hybrid seedlings.

After 1948, the scope of work on distant hybridization was sharply reduced, and work on directed education and vegetative hybridization was dramatically expanded (Chmora and Arnautov, 1953). At the same time, the main attention was paid to creating the most favorable conditions for the seedlings (fat background) in order to ensure the maximum yield, since it was believed that such yield would be preserved in the future. At the same time, they forgot that varieties bred against a fat background, when grown in production conditions against a much poorer background, sharply reduce their yield.

At present, when the ineffectiveness of the method of vegetative hybridization has become obvious to everyone, interest in distant hybridization in potatoes has increased again and interspecific crosses are beginning to be produced on a wider scale.

In the works of I. V. Michurin, the method of distant hybridization in the selection of fruits occupied a central place; on the basis of this method, he created an integrated synthetic approach to the problems of selection of vegetatively propagating forms. In this integrated approach, a number of methods were harmoniously synthesized and served as the basis for his breeding activity.

A rigorous analysis of this issue is especially necessary now, since many authors incorrectly presented the methods of IV Michurin's work. First of all, this concerns the role of vegetative hybridization, which is often described as almost the main method of Michurin's practical work.

In order to establish the real significance of different methods, to reveal their subordination in Michurin's breeding practice, there is only one reliable way. It is necessary to analyze, based on the materials of IV Michurin himself, how the best varieties were created by him.

The analysis is based on the study of the following materials: 1) data on the pomological description of varieties; 2) "List of new varieties of fruit plants bred by IV Michurin and subject to reproduction"; 3) "List of new varieties of fruit plants bred in the Kozlovsky garden nursery"; 4) "Inventory of plant material by IV Michurin", compiled by PN Yakovlev on behalf of IV Michurin.

As a result, data were collected on the breeding origin of 265 varieties and forms, which fall into the following 5 groups.

Varieties and forms obtained by hybridization (individual outstanding seedlings among first generation hybrids, from free crossing of first generation hybrids with other varieties, from repeated crossing of hybrids to cultivar).

We will give a list of varieties and forms obtained by hybridization, compiled by us on the basis of documents and materials left by IV Michurin. Apple trees: Anisovka, Antonovka yellow, Antonovka saffron, Bellefleur-record, Bellefleur-phoenix, Bessemyanka Michurinskaya, Bolshak, Borsdorf-Chinese, Daughter of Cinnamon, Calvil anise, Kandil-record, Chinese anise, Chinese golden early, Cream-Chinese, Komsomol Visant, Red Standard, Pendant-Kitaika, Paradizka Michurinskaya, Paradox, Pepin No. 4, Pepin-Kitaika, Pepin saffron, Pomon-Kitaika, Soviet, Ribbed, Renet sugar, Northern Buzhbon, Slavyanka, Taezhnoe, Truvor, Flava, Chelebi-Kitaika , Arkadovaya kitaika, Saffron-kitaika, Northern autumn saffron, Yakhontovoe, Sinap Michurina, Evolution, Seedling Kandil-kitaika, Winter Siberian, Winter sugar Renet, Severe Chuvash, No. 2009, hybrid Winter white Calvil X Chinese apple, Izumrud, Sina Green-leaved hybrid, Nedzvetsky hybrids - 1, 2, 3, 4, 5, Antonovka-tablet, Winter sweet, Brother Arcade of winter, Bellefleur-Chinese hybrid, Winter arcade, Salicil-Chinese, mestizo of Paper Reneta with Antonovka Kamenichka, Renet Michurina, Sharov ik, Easter anise, Calvilik, Pouring white autumn, Cinnamon Chinese, Antonovka sweet, Hermes, hybrid Kronsel X Bellefleur-Chinese, Anniversary turnip.

Pears: Bere winter Michurina, Bere kozlovskaya, Bere Pobeda, Room, Proletarian, Bere October, Russian Moldavka, Russian Esperen, Bergamot Kozlovsky, Sugar surrogate, Bere Tolstobezhka, Bere shallow, Bere autumn, Melisa, hybrid Saint-Germain X Thinkoveka, Dwarf, new pear variety, 1st sister Bere Michurina, Diana variegated, Lakovaya, Bere Ross, Bakhold's hybrid pear, Sister Bere winter Michurina, Kilbas bottle X Tsarskaya pear.

Quince: North.

Rowan: Black, Hybrid, Liqueur, Burka, Pomegranate, Michurinskaya dessert.

Cherries: Cherry bastard, Nadezhda Krupskaya, Ideal, Combine, Myrtle, Monomakh, Lazyabkaya, Black consumer goods, Polfir, Serving, Fertile, Michurina, Almond, Grace, Ultra-fruited, Grape, Hero of the early, Magma, Marked, Pioneer No., Vole, Tserap 1, Cerapadus is large, Cerapadus is sweet.

Plums: Oriental beauty, Transparent yellow, Golden Renklode, Kolkhoz Renklode, Peach, Renklode reform, Renklode of thorns, Apricot bastard, Caraway Renklode, Sweet turn, Dessert turn, Kozlovsky Prunes, Aghansky Renclode, Nizvetzha, Rosy, Pereklode Agro

Currant: Kyzyrgan.

Almond: Mediator, Michurin's almond.

Nut: Gretsky, Voloshsky.

Grape: Northern White, Northern Black, Northern Blue, Russian Concord.

Actinidia large Michurina; Improved Blackberry Strawberry; raspberry Arabka, raspberry Fairy; gooseberry Black negus; rose Queen of light; early ribbed melon, Cucumber melon, Kommunarka melon; lily Violet; tobacco Yellow Michurin.

There are 163 varieties and shapes in total.

Varieties obtained from individual outstanding seedlings, which appeared within the variety without the use of hybridization (mutations, algae).

Apple trees: Large tablet, Oleg, Renet Reshetnikova, Tablet aportovaya, Seedling of Kandilevaya seedling, Anise pear, Anise seedling, Chinese apple-tree Xiao-li, Calvil crimson, Seedling of aport Strelnikova, Mother of a Chinese woman, apple-trees Nedzvetsky, 4, Filya-1, Pomona, Popolevoe, Antonovka-sonfler, Ermak, Esaul Ermaka, Dessert Kitayka.

Pears: Butter Dilya, Limonka, Seed lemon, Pygmy, Second limonka, Moldavka seedling, Aurora, Coupon, Blankova's daughter, Oktyabrskaya.

Black currant: Ondine, Purple, Saffron, Black-fruited, Red-fruited, Amber-yellow round, Oval yellow, Crandal's seedling, Sorokovka, Grape.

Cherries: Ando, ​​Griot pear-shaped, Zakharovskaya, Practical, Rogneda, Japanese cherry.

Cherries: First Swallow, Firstborn, Kozlovskaya 3, Biggarro Michurina.

Plums: Chinese, Cannery, Low-growing Renklod, Victoria, Egg northern, MOPR, Egg.

Apricots: 84, 86, 241, 242, Best Michurin, Mongol, Satser, Comrade, Severny, Chitasatser.

Blackberry: Eastern, Abundant; raspberry texas.

Grape: Seedling Malengr, Zeta pink, Eastern, Boar, Large, Siberian productive, Taigovy.

Actinidia: Harvest, Early, Late, Pineapple Michurina, Clara Zetkin.

Gooseberry Anibut; hazelnut, YuglansManchurik variety walnut; white acacia Baikal, white North acacia; melon 50 days old.

There are 88 varieties and shapes in total.

Varieties obtained by using rare sports deviations (somatic mutations).

Apple trees: Antonovka one and a half pounds; pears: Bere folk; cherries: Anniversary.

Only 3 varieties.

Varieties obtained by hybridization from individual individually selected seedlings of first generation hybrids with the additional use of a mentor.

Apple trees: Bellefleur-Chinese, Bellefleur-red, Kandil-Chinese, Champanrene-Chinese.,

Cherries: Beauty of the North, Tern sweet, Almond Morel.

There are 7 varieties and shapes in total.

Varieties obtained from distant seedlings, selected during sowing varieties with the additional use of a mentor.

Apple trees: Renette bergamot;

pears: Bergamot Novik.

Only 2 varieties.

Analysis of IV Michurin's varieties and forms according to the methods of their breeding shows with the utmost clarity that distant hybridization was the main method of his work. Michurin himself has repeatedly emphasized this circumstance (see above). NV Tsitsin constantly draws the attention of our science and the public to this most important provision of IV Michurin's teachings (see, for example, NV Tsitsin, Remote hybridization is the main method of Michurin's work. Izvestia, October 20, 1955 g .; proceedings of the conference but hybridization, held in 1958, and other works).

In the works of N.V. Tsitsin himself and his collaborators, distant hybridization of wheat with wheatgrass led to great practical achievements in the form of the creation of valuable varieties of grain crops.

Above, by analyzing the history of the origin of 265 varieties of IV Michurin, we saw that 163 varieties, that is, more than 60%, were created from individual outstanding seedlings obtained by hybridization. We included 10 varieties from seedlings of the second generation in this group of varieties, because the seeds were sown from fruits obtained from free pollination. PN Yakovlev's remark is correct: "The genetic meaning that we usually put into the term" second generation "will not be here, since the first hybrid generation is obtained from free pollination, and even very heterozygous material." This group also includes several varieties obtained by IV Michurin from backcrossing to a cultivar. In addition, it should be noted that for such crops as apple, plum, and some others, the specific weight of the hybridization method was especially high. Among apple varieties, 76 were obtained on the basis of hybridization and 23 without it; among plums, 18 and 6 varieties, respectively, were obtained, etc.

It should be noted that no matter how great the significance of the remote hybridization method in Michurin's works, he nevertheless bred many varieties by selecting outstanding seedlings from among the usual crops of varieties, without the use of artificial hybridization. Among the 125 varieties analyzed by us, 88, that is, 30-35%, were created by IV Michurin by this method. It should be borne in mind that here, too, the selection of hybrid forms is not excluded due to natural pollination by other varieties with complex heterozygosity of both the varieties themselves and possible pollinators. Three varieties were obtained from individual cases of sports deviations (somatic mutations) and among them Antonovka one and a half pounds, or 600 grams - the first variety among apple trees bred by IV Michurin (first fruiting in 1888).

All this shows that the methods used by IV Michurin in his work are completely clear and deeply substantiated. Michurin himself hated the ascription of knowledge of some secrets to him, the fact that in his work some special methods were used in the form of recipes, having learned which you can easily create new varieties. In the note “On Methods,” he writes: “When I receive requests for an explanation of my methods of brooding new, qualitatively improved varieties of fruit plants, I find it hard to understand why they consider my work to be based on some special methods. Meanwhile, in essence, all my successes depend only on the fact that, starting each case, I first considered the task set for myself in all its smallest details from all sides ... Here, in general, everything depends on deep attention to the matter, from labor, most importantly, from patience and, of course, from the knowledge accumulated through long experience ... Where is there any special method? Meanwhile, as you can see, everyone is looking for some kind of gibberish, a non-existent secret, having discovered which, every quitter hopes to complete the job without much difficulty. "

If we turn to the zoning of varieties of vegetatively propagating plants, except for fruit (according to data for 1963-1964), we will find that in all cases the leading role is played by the methods of genetics, and primarily by distant hybridization (table).

We see that when creating varieties in different crops of vegetatively propagated plants, the main factors are the actions of selection and crossing. The main place in the selection of these plants is occupied by Michurin's deeply developed method of using heterosis and vegetative hybrids, which genetically combine valuable properties. We see that out of 109 varieties of domestic breeding, the origin of which is well known (141 minus 27 introduced varieties and 5 varieties of unknown origin), 73 varieties, i.e. 67%, originated in this way. Crossbreeding of different forms, which, being complex heterozygotes, give a huge form formation already in the first generation of hybrids, allows you to find unique valuable genotypes. It is impossible to save them during sexual reproduction. However, by vegetative propagation, any such genotypic combination can be maintained and propagated as a variety.

On potatoes, one can especially clearly compare, on the one hand, the results of work on the classical methods of Darwinism and genetics, and on the other, according to the methods of T. D. Lysenko. At this object, the techniques of vegetative hybridization and, loosening of heredity with obtaining tissue of different quality, in the case of their real significance, it would seem, should give especially effective results. In fact, of the entire varietal diversity, only in two cases there are dubious references to the role of vegetative hybridization.

After wheat, potatoes are the second largest source of carbohydrates in the global food balance. In 1963, the total area under potatoes was 24 700 thousand hectares, including 8 672 thousand hectares in the USSR. On average in wet weight, world potato production far exceeds the total yield of any cereal. We have seen that the overwhelming majority of the varieties currently released in the USSR have been obtained by hybridization and selection.

The outstanding Russian scientist and breeder Ivan Vladimirovich Michurin spent most of his life in the district town of Kozlov (Tambov province), which was later renamed Michurinsk in recognition of his work. He is considered one of the founders of the science of fruit crop breeding. From a young age he was fascinated by work in the garden. His whole life was devoted to one goal: to develop new high-yielding varieties of agricultural crops in the climatic conditions of Russia. And he managed to achieve this dream, despite the incredible difficulties and hardships.

One of the most important results of his many years of work was the original practical methods he developed for producing hybrids with new, valuable properties. In addition, on the basis of the work done, he made very important theoretical conclusions.

Initially Michurin set himself the task of acclimatizing the southern varieties of fruit trees to the conditions of central Russia. However, a failure awaited him here, due to the fact that the heat-loving southern varieties of plants, even if grown in the new conditions, could not stand the harsh winter. This is due to the fact that one change in the conditions of existence of an organism cannot change a phylogenetically developed stable genotype, moreover, in a certain direction.

Thus, Michurin realized that the acclimatization method did not give the desired results. This led him to the idea that it is possible to obtain varieties with the required properties if one crosses one with another, that is, by engaging in breeding work. Three main types of influence were used by Michurin in his work: hybridization, education of a developing hybrid under various conditions, and selection.

^

Hybridization method

Getting a variety with new, improved characteristics is called hybridization. As a rule, it is carried out by crossing a local variety with a southern one with a higher taste. However, due to the historical adaptability of the local variety to the conditions of existence of the given area, the characteristics of the local variety were dominant in the resulting hybrids.

In order for hybridization to be successful, Michurin took parents from very remote geographical areas for crossing. Michurin believed that in this case unilateral domination would not occur, since the conditions of existence would not be familiar to any of the parental forms. Based on this, it is possible to control the development of the new resulting hybrid.

Subsequently, Michurin practically proved the validity of the above statement, having received a completely new pear variety Bere Zimnyaya Michurin. It was distinguished by large, maturing fruits with good taste, while the hybrid plant itself tolerated cold up to -36 °. The southern pear variety Bere Royal with large juicy fruits was taken as the father, and the wild Ussuri pear with small fruits and high winter hardiness was taken as the mother. For both parents, the conditions of central Russia were unusual.

Michurin also selected and crossed local frost-resistant varieties with southern thermophilic varieties, which differed in other characteristics. He strictly observed that the resulting hybrids were frost-resistant. Thanks to this, the Slavyanka apple variety was obtained from the crossing of Antonovka with the southern Ranet pineapple variety.

Michurin's experiments on crossing plants of different species were also widely known, while interspecific and intergeneric hybrids were obtained, such as hybrids between cherry and bird cherry (cerapadus), between apricot and plum, plum and blackthorn, rowan and Siberian hawthorn, etc.

Under natural conditions, crossing of varietal plants does not occur due to the fact that foreign pollen of another species is not perceived by the mother plant. Michurin used several methods to overcome non-breeding during distant hybridization.

^ Pre-vegetative rapprochement method

This method was used by Michurin when crossing rowan and pear. It consists of two stages.

First, an annual cutting of a hybrid rowan seedling (scion) is grafted into the crown of a plant of another species or genus, for example, to a pear (stock). After 5-6 years of nutrition due to the substances produced by the stock, there is some change, the convergence of the physiological and biochemical properties of the stock.

Then, during the flowering of mountain ash, its flowers are pollinated with the pollen of the rootstock. In this case, crossing is carried out.

^ Mediator method

The essence of this method is that in case of impossibility of direct hybridization of two forms of plants, a third is used. This plant is crossed with one of the first two, and then the resulting hybrid is crossed with the second, resulting in a hybrid of the first two forms. The third form acts as a mediator.

The mediator's method was used by Michurin when crossing a cultivated peach with a wild Mongolian bean almond (to increase the frost resistance of the peach). Since direct crossing of these forms was not successful, Michurin crossed the legume with the semi-cultivated peach of David. Their hybrid was crossed with a cultivated peach, for which he was named an intermediary.

^ Pollination method with a mixture of pollen .

IV Michurin used various versions of a mixture of pollen. A small amount of the pollen of the mother plant was mixed with the pollen of the father. In this case, its own pollen irritated the stigma of the pistil, which became able to perceive foreign pollen as well. When the flowers of an apple tree were pollinated with pear pollen, a little apple pollen was added to the latter. Part of the ovules was fertilized with their own pollen, the other part was foreign (pear).

Non-breeding was also overcome when the flowers of the mother plant were pollinated with a mixture of pollen of different species without adding pollen of their own variety. Essential oils and other secrets secreted by foreign pollen irritated the stigma of the mother plant and facilitated its perception.

Through all his many years of work on the development of new varieties of plants, IV Michurin showed the importance of the subsequent upbringing of young hybrids after crossing.

When raising a developing hybrid, Michurin paid attention to the composition of the soil, the method of storing hybrid seeds, frequent transplantation, the nature and degree of nutrition of the seedlings, and other factors.

^

Mentor Method

This method was developed by Michurin and was widely used by him in practice. It consists in the fact that a seedling is grafted into a plant that has the necessary qualities for bringing up desirable qualities in a hybrid seedling. As a result, the desired qualities are enhanced in the hybrid, and its further development proceeds under the influence of substances produced by the plant-educator (mentor). In this case, during the development of hybrids, a change in the properties of dominance occurs. In this case, both the rootstock and the scion can be a mentor.

By the method of the mentor Michurin bred two varieties - Bellefleur-Kitayka and Kandil-Kitayka.

Kandil-Kitayka is the result of crossing Kitayka with the Crimean variety Kandil-Sinap. Michurin grafted the hybrid into the crown of the frost-hardy mother Kitayka in order to develop and consolidate the frost-hardiness sign. Thanks to the nutrition of the mother's substances, the hybrid acquired the desired quality.

The second variety, Bellefleur-Kitayanka, was bred to prevent the hybrid from deviating towards the frost-resistant and early-maturing Kitayanka, and therefore the fruits of the hybrid could not be stored for a long time. Michurin planted several cuttings of late-ripening varieties in the crown of the Bellefleur-Chinese hybrid seedling in order to increase keeping quality in the hybrid. As a result of the hybridization, the Bellefleur-Chinese fruits became more mature and mature.

The effect of this method can be regulated by the following methods:

1) the duration of the mentor's activity; 2) the ratio of the age of the mentor and the hybrid; 3) the quantitative ratio of the foliage of the mentor and the hybrid.

The older the mentor is, the richer the foliage of the crown and the longer it acts, the higher the intensity of its action. When carrying out breeding work Michurin made repeated and rather strict selection, which made it possible to obtain hybrids of excellent quality. Hybrid seeds were selected for their roundness and size; hybrids - according to the configuration and thickness of the leaf blade and petiole, the shape of the shoot, the location of the lateral buds, winter hardiness and resistance to fungal diseases, pests and many other signs, and, finally, the quality of the fruit.

As a result of his research IV Michurin created several hundred new varieties of plants. New cold-resistant varieties of apple and berry crops were bred. These plants are characterized by high palatability and at the same time are perfectly adapted to local conditions. One of these types is the Antonovka apple variety, six hundred grams, which gives a yield from one tree up to 350 kg. The grapes bred by Michurin withstood the winter without dusting the vines, which is done even in the Crimea. However, he did not reduce his commodity indicators.

I. V. Michurin with his works turned the idea of ​​human capabilities and laid a solid foundation for further research on plant breeding

Bibliography

Biology manual for university applicants. Minsk, I., "Higher School", 1978

Encyclopedic Dictionary of a Young Naturalist. Moscow, I., "Pedagogy". 1981 year

IV Michurin is an outstanding scientist-breeder, one of the founders of the science of selection of fruit crops. He lived and worked in the district town of Kozlov (Tambov province), which was renamed Michurinsk in 1932. Working in the garden from a young age was his favorite thing. He set himself the goal of his life to enrich the gardens of Russia with new varieties and achieved the realization of this dream, despite incredible difficulties and hardships.

He developed original practical methods for obtaining hybrids with new properties useful for humans, and also made very important theoretical conclusions.

Having set himself the task of promoting southern varieties of fruit trees in central Russia, Michurin first tried to solve it by acclimatizing these varieties in new conditions. But the southern varieties grown by him froze out in winter. A change in the conditions of existence of an organism alone cannot change a phylogenetically developed stable genotype, moreover, in a certain direction.

Convinced of the unsuitability of the acclimatization method, Michurin devoted his life to breeding work, in which he used three main types of influence on the nature of the plant: hybridization, education of a developing hybrid under various conditions, and selection.

Hybridization, that is, obtaining a variety with new, improved characteristics, was most often carried out by crossing a local variety with a southern one, which had a higher taste. At the same time, a negative phenomenon was observed - the dominance of the characteristics of the local variety in the hybrid. The reason for this was the historical adaptation of the local variety to certain conditions of existence.

Michurin considered the selection of parental pairs to be one of the main conditions contributing to the success of hybridization. In some cases, he took parents for crossing, distant in their geographical habitat. If the conditions of existence for parental forms do not correspond to their usual ones, he reasoned, then the hybrids obtained from them will be able to more easily

adapt to new factors, as there will be no unilateral domination. The breeder will then be able to manage the development of a hybrid that adapts to new conditions.

This method was used to develop the pear variety Bere Zimnyaya Michurina. As a mother, the Ussuriyskaya wild pear was taken, distinguished by small fruits, but winter-hardy, as a father - the southern variety Bere Royal with large juicy fruits. For both parents, the conditions of central Russia were unusual. The hybrid showed the qualities of the parents necessary for the breeder: the fruits were large, mature, had high taste, and the hybrid plant itself tolerated cold up to -36 °.

In other cases, Michurin selected local frost-resistant varieties and crossed them with southern thermophilic ones, but with other excellent qualities. Carefully selected hybrids Michurin brought up in Spartan conditions, believing that otherwise they will have traits of thermophilicity. This is how the Slavyanka apple variety was obtained by crossing Antonovka with the southern Ranet pineapple variety.

In addition to crossing two forms belonging to the same systematic category (apple and apple, pear and pear), Michurin also used the hybridization of distant forms: he received interspecific and interspecific hybrids.

He obtained hybrids between cherry and bird cherry (cerapadus), between apricot and plum, plum and blackthorn, mountain ash and Siberian hawthorn, etc.

Under natural conditions, foreign pollen of another species is not perceived by the mother plant and crossing does not occur. To overcome non-breeding during distant hybridization, Michurin used several methods.

Ivan Vladimirovich Michurin, an outstanding Soviet scientist and breeder, devoted 60 years of hard work to the development of new varieties of fruit trees and other cultivated plants. His work began in the 70s of the last century in a small nursery in the town of Kozlov (now Michurinsk), the former Tambov province.

To expand the research of I.V. Michurin was able to only after the October Revolution, when his nursery was turned into a large state institution. V.I. was interested in Michurin's activities. Lenin, who attached great importance to it. M.I. Kalinin visited Michurin's nursery and in every possible way contributed to his work.

I.V. Michurin did not immediately arrive at the methods and views that led to great success. In the first period of his activity, he spent a lot of time and energy on experiments on simple acclimatization (training) of southern varieties to the relatively harsh climate of the Tambov province with cold winters. These attempts were unsuccessful. All southern varieties were frozen in winter.

Convinced of the futility of the method of simple acclimatization, I.V. Michurin began to develop new methods for changing the nature of plants.

The works of I.V. Michurin is a combination of three main methods: hybridization, selection and environmental impact on developing hybrids(their "education" in the desired direction).

I.V. Michurin devoted himself to the selection of the initial parental forms for hybridization. He used crossbreeding of local frost-resistant varieties with the best southern ones. The resulting seedlings were subjected to rigorous selection. I.V. Michurin kept the hybrids obtained in this way in relatively harsh conditions, without giving them rich soil. IV Michurin points to the possibility of controlling the dominance of traits during the development of a hybrid, and the influence of external factors on dominance is effective only in the early stages of hybrid development. The varieties obtained by this method include, for example, the Slavyanka apple tree, bred as a result of hybridization of Antonovka with the southern variety Ranet pineapple.

Of particular importance in the selection of parental forms for hybridization I.V. Michurin gave the crossing geographically distant forms that do not grow in the area where hybridization is carried out. He wrote in this regard: "The further apart the pairs of crossed breeding plants are in the place of their homeland and environmental conditions, the easier it is for the hybrid seedlings to adapt to the environmental conditions in the new locality." This way I.V. Michurin created a number of first-class varieties of fruit trees. Among them is the Bellefleur-Chinese apple variety, obtained as a result of hybridization of the Chinese apple tree from Siberia and the American Bellefleur yellow variety. Kitayka is characterized by hardiness to frost and disease resistance, Bellefleur - by the remarkable taste of the fruit. Received by I.V. Michurin, the new variety is distinguished by excellent taste and significant frost resistance.

The widely known Michurin pear variety Bere Zimnaya Michurina was obtained as a result of hybridization of the wild Ussuri pear and the southern French variety Bere-Royal.

Among the methods of "education" developed by I.V. Michurin, one should point out mentor method. Its essence boils down to the fact that the characteristics of a developing hybrid change under the influence of a scion or rootstock. This method was used by Michurin in two versions.

The first of them boiled down to the fact that the hybrid seedling served as a scion and was grafted onto an adult fruiting plant (stock), in the direction of the properties of which it was desirable to change the properties of the hybrid.

The second version of the mentor's method consisted in the fact that in the crown of a young hybrid seedling, which in this case served as a stock, a cutting was grafted from the variety in the direction of which it was desirable to change the properties of the hybrid.

The mentor's method was applied by I.V. Michurin, for example, when creating the already mentioned apple variety Belle Fleur-Chinese. In the first year of fruiting of the hybrids that gave rise to the variety, it turned out that, in terms of fruit quality, they deviate towards Kitayka, which has small sour fruits. To change the further development of the hybrid in the desired direction, Bellefleur cuttings were grafted into the crown of young hybrids, under the influence of which the formation of the hybrid trait in subsequent years went towards acquiring the high taste of Bellefleur. This method was applied by I.V. Michurin and when creating some other varieties, but he did not receive widespread use. The influence of the mentor should, obviously, be considered as a change in the property of dominance in the process of hybrid development. In this case, the mentor contributed to the phenotypic manifestation (i.e., dominance) of the genes obtained from the Bellefleur variety.

In his work I.V. Michurin also used distant hybridization - crossing between different species and even genera, and thus obtained several valuable new fruit crops.

He obtained hybrids of blackberries and raspberries, plums and thorns, mountain ash and Siberian hawthorn, etc.

The majority of I.V. The Michurin varieties were complex heterozygotes. To preserve their qualities, they reproduced vegetatively: by layering, grafting, etc.

In his work, IV Michurin made extensive use of hybridization. In doing so, he took into account the complex nature of the hybrids. He believed that hybrid seedlings go through critical periods at various stages of development, during which the implementation of different-quality parental genes takes place.

Based on this assumption, IV Michurin used methods of raising seedlings, influencing them with environmental factors. He used various methods of tillage, fertilization, the mentor's method.

Mentor Method consists in the fact that in the crown of the hybrid seedling a graft is made from the plant, the properties of which must be transferred to the hybrid. Sometimes the hybrid is grafted onto the corresponding stock.

Remote hybridization in the works of Michurin

IV Michurin also widely used and. He found that when southern varieties hybridize with local varieties, the traits of local varieties usually dominate. To avoid this, he came to the conclusion that it was necessary to match parents from different geographic areas.

Thus, he developed the Bere winter pear variety thanks to the hybridization of the South European pear Bere a grand piano with the Ussuri pear. With such hybridization in a hybrid, the hereditary basis of both initial parental forms is found in unusual natural conditions.

By changing the conditions for growing hybrids, Michurin brought up economically valuable traits from them, borrowed from one or the other of the parents. In this particular case, the Bere Zimnaya variety inherited from its southern parent large-fruited, high taste and the possibility of long-term winter storage, and from the Ussuriysk parent - cold resistance.

Due to the fact that organisms under the influence of the environment can change within the limits of the reaction norm, external factors can influence the phenotypic manifestations of traits. This was used by Michurin when growing hybrids of fruit trees, changing certain conditions at different stages of ontogenesis. The dominance of traits that find the most favorable conditions for development in the environment, Michurin called dominance control.

To overcome non-breeding during distant hybridization, Michurin developed a number of methods.

Michurin's methods

Vegetative convergence method consists in the preliminary grafting of one type of plant onto another. As a result, the chemical composition of tissues changes, which, apparently, contributes to the germination of pollen tubes in the pistil of the mother plant. Thus, it is possible to achieve fertilization during hybridization of species that usually do not cross.

Mediator method is that, if it is necessary to obtain a hybrid between non-breeding species A and B, the hybridization of the crossing of species B with C is first carried out, and the hybrid is crossed with species A.

Pollination method with a mixture of pollen from different species may also favor the germination of pollen tubes in the flower pistil and promote fertilization.

Most of the varieties bred by Michurin are heterozygous in genotype, therefore they cannot be reproduced sexually, they will split. They are propagated vegetatively.

Michurin paid much attention to the acclimatization of southern fruit plants and laid the foundation for the advancement of grapes, apricots, cherries, etc. to the north.

A lot has been done by breeders to develop new varieties of agricultural plants. Great is the merit of N.V. Tsitsin, P.P. Lukyanenko, V.N. Remeslo, F.G. Kirichenko, V.E. Pisarev, who developed new varieties of wheat. V.S. Pustovoit created high-oil varieties of sunflower, I.M. Khadzhinov achieved great success in breeding corn.