What is a hybrid. What is a cucumber hybrid? Natural product or dangerous mixture. Hybrids in scientific nomenclature

In recent years, people have begun to seriously think about the ecology of the planet. And automakers are eagerly supporting this trend by creating vehicles that run on environmentally friendly fuels. As for electric vehicles, they are not yet being seriously considered. The same cannot be said for hybrid vehicles, which are gaining more and more popularity.

What is a hybrid car. Pros and cons of the "hybrid".

What is a hybrid car? The word hybrid comes from the Latin "hibrida", which means a cross. That is, an organism that is obtained by crossing genetically different parental forms. In our case, the parental forms are the electric motor. In one sentence: A hybrid vehicle is an electric motor-combustion engine vehicle that is highly efficient. This unit can be powered by both traditional fuel and electricity from batteries.

Each of the engines has its own specific function. For example: if the car is standing, for example, in a traffic jam, or is moving slowly, the electric motor will work. When the car picks up speed, the gasoline engine comes into play.

Pros of hybrid vehicles.

The biggest plus of hybrid cars is that they are very economical... As a rule, their fuel consumption is 25% less than that of traditional cars. And in the face of constantly rising gasoline prices, this point is the most important.

The next most important item is environmental friendliness. Hybrids do less damage to our eco-system than conventional cars. This is achieved through more rational fuel consumption. Also, when the car comes to a complete stop, the gasoline engine stops working, giving the initiative to the electric motor. That is, during stops, there is practically no carbon dioxide emissions into the atmosphere.

Unlike electric vehicle batteries, in hybrids, batteries can be recharged from a gasoline engine... Which makes its power reserve large enough. In addition, it takes longer without refueling.

Many people think that hybrids are far inferior in performance to traditional cars. This is not true. All the necessary characteristics (power, overclocking from zero to one hundred, and so on), they have, are no worse.

Best of all, hybrid cars feel at home in the city cycle, in which there are very frequent stops and the engine runs a lot when idling. In practice, in the city, it works like an electric car. If we talk about the mixed cycle, then here they have no particular advantages.

Toyota Prius is the most popular hybrid in Russia.

As already mentioned, if the car is stationary, then it switches to the electric motor mode. That gives almost complete noiselessness.

Well, the hybrid car is fueled with ordinary hydrocarbons, that is, gasoline... Everything is done in a standard way, like with traditional cars.

Cons of hybrid vehicles.

Nothing is perfect, and it also has its drawbacks. And the main one is that repairing hybrid cars is much more expensive than repairing a car with traditional equipment. This is explained by the complexity of the design of the engine device.

Also, due to the complexity of the design, it is difficult to find professionals who can fix the engine.

The batteries that come with the hybrids can self-discharge. In addition, they cannot withstand large temperature fluctuations and their lifespan is rather limited.

In addition, it is not yet known how used batteries affect the environment. Therefore, their disposal is also a problem.

Despite the fact that hybrid cars have more advantages, they are not yet popular in Russia. One of the reasons for this is the price. The cost of the most popular hybrid Toyota Prius in our country is from 1,200,000 rubles. And this car is the cheapest hybrid. Also, for the mass buyer they plan to release a Russian development of a hybrid car, the so-called "Yo-Mobile". Its price can be from 350,000 rubles. However, this project was closed.

The BMW ActiveHybrid X6 is the most powerful hybrid vehicle to date.

In connection with the struggle for the environment, buyers around the world are encouraged to purchase hybrids. So, in the United States there are a number of tax incentives for the owners of such cars, and even free parking spaces. In our country, they are also going to introduce similar laws. In particular, the reduction of duties on the import of hybrid vehicles.

Engines running on hydrocarbons will slowly but surely lose their positions. And hybrids are one of those steps. However, as long as prices for them remain at the same level, the demand for them will be small.

), obtained as a result of crossing genetically different forms. The concept of hybrid is especially common in botany, but it is also applied in zoology.

In industrial and amateur floriculture, the term Greek is also used. grex). Introduced by Carl Linnaeus for the use of binomial nomenclature in the classification of artificial hybrids.

Hybrids can be intraspecific (when crossing different varieties, forms, varieties), intrageneric (when crossing species belonging to the same genus) or intergeneric (when crossing species belonging to different genera).

In the XVIII century. hybrids in the Russian folk language were called "bastards". In 1800 Smelovsky T.A. introduced the term "hybrids", which existed throughout the 19th century, and only in 1896 A.N. Beketov proposed the term "hybrids".

Reciprocal hybrids

Reciprocal hybrids appear as a result of reciprocal crosses - hybridization that involves reversing the sex of the parents associated with each genotype.

Reciprocal effects

The differences between reciprocal hybrids - reciprocal effects - indicate the unequal contribution of males and females to the genotype of the offspring. If the offspring from the father and mother received the same genetic information, then there should have been no reciprocal effects.

Measuring reciprocal effects

To measure reciprocal effects (r), you can use the expression:

where A and B are the values ​​of the trait for the original crossed forms; a - the same for the hybrid ♂A x ♀B; b - for reciprocal hybrid ♂B x ♀A. A positive value of r (r> 0) would mean a “paternal” effect, negative (r< 0) - «материнский», а абсолютная величина r (│r│) даст относительную оценку этих эффектов в единицах, равных разности значения признака для исходных форм (B - A).

Reciprocal effects in birds

In chickens, the “paternal” effect was observed according to the inheritance of the brooding instinct (r = 0.45, 0.38, and 0.50), sexual maturity (r = 0.59), egg production (r = 0.32, −2.8, 1.07, 0.11, 0.46, 1.14, and 2.71), and live weight (r = 0.30).

According to the weight of the eggs, a “maternal effect” was observed (r = −1.0).

Reciprocal Effects in Mammals

In pigs, the “paternal” effect is observed in the number of vertebrae (selection for a long body) (r = 0.72 and 0.74), the length of the small intestine (selection for better food payment), and growth dynamics (selection for early maturity) (r = 1.8).

The “maternal effect” was observed in terms of the average weight of embryos, the digestive system and its parts, the length of the large intestine, and the weight of newborn piglets.

In cattle, the “paternal” effect was observed in milk yield (r = 0.07, 0.39, 0.23) and milk fat production (amount of fat) (r = 1.08, 1.79, 0.34).

The "maternal effect" was observed in terms of the percentage of fat in milk in cows (r = −0.13, −0.19, −0.05).

Reciprocal effect theories

"Maternal effect"

The maternal effect may be due to cytoplasmic inheritance, homogametic constitution, and uterine development in mammals. Distinguish between the actual maternal effect, when the mother's genotype is manifested in the phenotype of the offspring. Molecules in the egg, such as mRNA, can influence the early stages of the development process. There are also maternal inheritance, in which part of the genotype the offspring receives exclusively from the mother, for example, mitochondria and plastids containing their own genome. In maternal inheritance, the phenotype of the offspring reflects its own genotype.

"Paternal effect"

The greater influence of the father on the egg production of daughters in chickens was explained by the fact that in birds the female is the heterogametic sex, and the male is homogametic. Therefore, the chicken receives its only X chromosome from the father, and if egg production is determined by it, then everything is clear. This interpretation can explain the chromosomal mechanism of the phenomenon in birds, but is no longer applicable to mammals. It is also surprising that the signs that appear only in the female sex (the incubation instinct, early maturity and egg production in a hen or milk yield and the amount of milk fat in a cow), which, it would seem, should be transmitted by the mother, are nevertheless transmitted more by the father.

Interspecies and intergeneric hybridization

Interspecific hybridization is often observed both in nature and during human cultivation (keeping in captivity) in many species of plants and animals. In nature, in areas of contact of closely related species, so-called "hybrid zones" can form, where hybrids numerically prevail over parental forms.

Interspecific introgressive hybridization is widespread in daphnia. In some summer populations of Daphnia, hybrids predominate, which makes it difficult to determine the boundaries of species /

Notable experimental hybrid rafanobrassica(lat. Raphano-brassica) was obtained by G. D. Karpechenko by crossing radish with cabbage. Both species belong to different genera and have 18 chromosomes. The hybrid obtained as a result of doubling the number of chromosomes (36) was capable of reproduction, since in the process of meiosis the chromosomes of radish and cabbage were conjugated with their own kind. He possessed some of the characteristics of each of the parents and kept them clean when breeding.

Intergeneric hybrids (both natural and obtained by breeders) are also known in the families of cereals, rosaceae, citrus, orchids, etc. Thus, the hexaploid genome of soft wheat was formed by combining the diploid genomes of two ancestral wheat species and one species of a close genus Aegilops.

Hybrids in scientific nomenclature

In botany

Hybrid plant taxa are called nototaxons.

In zoology

Sterility of hybrids

Unfavorable interactions between cytoplasmic and nuclear genes also lead to sterility of interspecific hybrids in different groups of plants and animals.

Plant and animal species often differ in translocations, inversions, and other rearrangements that, in a heterozygous state, cause semi-sterility or sterility. The degree of sterility is proportional to the number of independent rearrangements: so heterozygosity for one translocation gives 50% sterility, for two independent translocations - 75% sterility, etc. The sterility of plants is determined by the gametophyte. In heterozygotes for chromosomal rearrangements, as a result of meiosis, daughter nuclei are formed, carrying deficiencies and duplications in certain areas; functional pollen grains and ovules are not obtained from such nuclei. Chromosomal sterility of this type is very common in interspecific hybrids of flowering plants.

The course of meiosis in a hybrid can be disturbed either by genetic factors or by differences in the structure of chromosomes. Both gene and chromosomal sterility can be expressed in an aberrant course of meiosis. But the types of meiotic aberrations are different. Gene sterility is common in animal hybrids, and chromosomal sterility in plant hybrids. Genetic analysis of some interspecific plant hybrids shows that often one hybrid has both chromosomal and gene sterility.

Destruction of hybrids

In cases where a certain interspecific hybrid is sufficiently viable and capable of reproduction, the generations of its offspring will contain a significant proportion of non-viable, sub-vital, sterile and semi-sterile individuals. These types are unsuccessful recombination products resulting from interspecies hybridization. This suppression of vigor and fertility in hybrid offspring is called hybrid breakdown. The destruction of hybrids is the last link in a sequence of barriers that prevent interspecific gene exchange.

Decomposition of hybrids is invariably found in the progeny of interspecific hybrids in plants, where it is easier to observe than in most crosses in animals.

Hybrids with their own names

Hybrids in the Orchid family

The selection of phalaenopsis and other flowering orchids is developing in two directions: for cutting and for potting.

Some artificial genera of orchids:

• Brassolaeliocattleya
• Rhynchosophrocattleya

see also

Notes (edit)

1. A. A. Shcherbakova The history of botany in Russia until the 60s of the XIX century (Dodravinov period). - Novosibirsk: "Science", 1979. - 368 p.
2. Roberts E., Card L. (1933). V World Poultry Congr., 2 , 353.
3. Morley F., Smith J. (1954). "Agric. Gaz. N. S. Wales " 65 , N. 1, 17.
4. Saeki J., Kondo K., et al. (1956). "Jpn. J. Breed. " 6 , N. 1, 65.
5. Warren D. (1934). "Genetics" 19 600.
6. Dubinin N.P., Glembotskiy Ya.L. (1967) Population genetics and breeding. - M .: Science p. 487, 496.
7. Dobrynina A. Ya. (1958) Reciprocal crosses of Moscow chickens and Leghorns. Tr. Institute of Genetics of the USSR Academy of Sciences, M, No. 24, p. 307.
8. Aslanyan M.M. (1962) Peculiarities of inheritance and embryonic development of piglets when crossing large white pigs and Swedish Landrace. Scientific. report higher. schools, no. 4, p. 179.

In recent years, a huge number of seeds of F1 hybrids of vegetables and flowers have appeared on the market. However, it is with them that the most questions are connected. Why, for example, bags with F1 seeds are much more expensive than "regular" varieties, and there are very few seeds in them (5-10 pcs.)? Why are their descriptions especially tempting - "sustainable", "fruitful", "highly decorative", "large-flowered", etc.? It happens that sellers warn: "You cannot collect your seeds from hybrids, as there will be splitting in the future." Finally, one sometimes hears from amateur gardeners that "hybrids are probably the same as transgenic plants, they are not safe for health." Let's find out what hybrids really are?

The most important feature of the variety is its ability to retain all its positive and negative properties in the next offspring. When obtaining and harvesting seeds from plants of a common variety, especially from self-pollinating (tomato, peas, beans) or partially self-pollinating vegetable crops (pepper, eggplant, lettuce, beans), in the subsequent offspring we will get plants with almost exactly the same set of traits. This ability to transfer all its properties to the offspring makes it easy to maintain and multiply, even on a personal plot, varieties of self-pollinating crops. But with mass harvesting of seeds, when regular selection of the best plants for a given variety is not used, within 3-5 years, some characteristics characteristic of this variety may be lost. There is, as vegetable growers say, the degeneration of the variety. Therefore, with a well-established seed production of varieties, even self-pollinated vegetable crops, once every 3-5 years it is necessary to purchase the seeds of the elite of the variety you like in a specialized gardening store.
It is much more difficult, but it is also quite possible to propagate or maintain a variety of any cross-pollinated vegetable crop - cucumber, cabbage, zucchini, carrots, beets, pumpkin, watermelon, etc. leads to over-pollination, and, consequently, to partial or complete loss of characteristics characteristic of a given variety. And the closer two different varieties are located, the stronger the cross-pollination occurs. At the same time, in the offspring we receive, a mixture of traits of two, three or more varieties is observed, as a result, the variety disappears and we have a set of plants with completely different traits and properties and low productivity. A bee or bumblebee carrying pollen freely fly from flower to flower over a distance of up to 2000 m.
Therefore, the reproduction of even simple cross-pollinated varieties on your personal plot requires special knowledge of the biology of flowering of a particular culture. If you observe spatial or any other isolation, as well as carry out forced self-pollination, then in the next offspring a well-selected variety will generally retain all its inherent properties. Thus, in a simple variety, it is possible for several years to obtain and harvest seeds, from which plants will grow that have retained all its main characteristics.
A hybrid variety or an F1 hybrid propagates in a completely different way. Two centuries ago it was known that when two different varieties are crossed in the offspring, the size of plants increases noticeably, their growth and development are accelerated, and early maturity and productivity increase. This phenomenon, that is, an increase in vitality in the offspring obtained from the crossing of two different varieties, is called heterosis. And the more contrasting the parental varieties, the more they differ from each other, the higher the heterosis.
The practical use of the phenomenon of heterosis began in the 20-30s of the last century. For all vegetable crops, heterotic selection is carried out and F1 hybrids are obtained, which are widely used in production. In countries with developed agriculture, ordinary varieties are practically not grown in vegetable growing. They have been ubiquitously replaced by F1 hybrids. In our protected ground, where every square meter is registered, only F1 hybrids of cucumber and tomato are used.

HYBRIDS F1 AND F2.
A hybrid is the offspring obtained from the crossing of two genetically heterogeneous parental forms: species, lines, varieties, etc. denoted by the Latin letter F and the number 1. If you collect seeds from F1 hybrids and sow them, then next year hybrids of the second generation, or F2, will grow (this designation can be found on bags with seeds of flower crops).

WHAT ARE THEIR ADVANTAGES? Different parents used in crossing may have some advantage (for example, one is disease resistant, the other is early maturing), and the resulting hybrid will have both advantages at the same time (in this case, it will be both early maturing and disease resistant). Thus, by specially selecting parents for crossing, it is possible to obtain hybrids with a set of specified positive traits that the "normal" variety does not possess. F1 hybrids are distinguished by a high level of adaptation to adverse factors. In early spring, with sudden changes in air temperature or summer heat, F1 hybrids develop much better than conventional varieties. A high level of adaptation to unfavorable factors contributes to obtaining consistently high yields.

An equally important requirement for F1 hybrids is their genetic resistance to diseases and pests. This is especially true when growing vegetables in film greenhouses. The specificity of the microclimate of protected ground, long-term cultivation in one place of one or two crops lead to a significant accumulation of pathogenic microflora and fauna. Chemical methods of controlling diseases and pests in greenhouses are not always effective and reliable. In addition, tomato or cucumber fruits intended for fresh consumption should not contain pesticide residues. Therefore, the genetic resistance of F1 hybrids to diseases due to the combination of the traits of the two parental lines is always higher than that of conventional varieties. Already obtained and used in the production of F1 tomato hybrids with group resistance to three or four diseases (tobacco mosaic virus, brown leaf spot, fusarium, verticillosis) and root-knot nematodes.

For seeds only in a special store.

Unlike conventional varieties from hybrid plants, it is unacceptable to harvest seeds. The offspring, due to splitting, turns out to be so variegated and heterogeneous that there can be no question of any high yield. The fact that F1 hybrid seeds have to be purchased from the store every time is their only drawback.
It is impossible to get hybrid seeds on your own in a backyard economy without the original parental lines. Therefore, if you see F1 hybrid seeds for sale from private traders, then this is probably not true. When you buy hybrid seeds from the market, you risk your harvest.
Now about the price of seeds for F1 hybrids. All work on crossing two parental lines to obtain hybrid seeds is carried out, as a rule, manually in protected ground. For example, on a tomato culture, when F1 hybrids are obtained, it is necessary to trim (that is, remove the stamens) all the opening flowers on the maternal line, prepare pollen from the opened flowers of the paternal line with a vibrator and very carefully apply it several times (within two to three days) on stigma of the pistil. Hybrid seed production continues every day for two to three months. One person can receive only 3-4 kg of hybrid tomato seeds per season. Therefore, the price for hybrid seeds is several times higher than for ordinary varietal ones. For the buyer, the cost of seeds is only 0.5-1% of the cost of the resulting product and justifies itself in the harvest. However, the question arises:

Why do we need this?

Man has always tried to get a larger crop per unit area.
With the development of technologies for growing agricultural products, the requirements for varieties are changing. So, with the advent of harvesters for harvesting, varieties with fruits that are resistant to contact with the mechanical parts of the harvester were required. With the development of the processing industry, there is a demand for varieties, the fruits of which are ideal for various processing methods (canning, pasta production, drying, freezing, etc.). With the increase in the area of ​​protected ground, it became necessary to create special varieties for these growing conditions.
The development of economic ties and trade between different regions and countries in order to ensure a year-round supply of fresh vegetables and fruits has contributed to the development of varieties that tolerate transportation well while maintaining high commercial qualities.

As you can see, the creation of new varieties is an objective necessity for the successful development of traditional agriculture and the processing industry. Professional growers work only with hybrids when growing vegetables and flowers.

The bio-dynamic direction of agriculture does not use or recognize hybrids, claiming that their quality and nutritional value for humans are controversial issues. The use of hybrids in floriculture is completely justified: they surpass varieties in compactness, abundant flowering and color range. And whether it is necessary to grow vegetable hybrids for their nutrition, it is up to everyone to decide for himself.

What are hybrids? How are they made? What are the advantages of hybrid seeds over varietal seeds. Why hybrid seeds are more expensive than varietal seeds. Why seeds obtained from hybrid plants are not recommended for growing in subsequent years.

Hybrid seeds are the fruit of the patient breeders' labor. The seeds of the first generation hybrids are on sale. The distinguishing mark of the hybrid that distinguishes it from the variety is the F1 symbol. For example "Farmer F1". F - These are children (from Italian Filli). 1 is the generation number.

Hybrids are obtained by artificial pollination of flowers of different varieties of the same culture. For such a crossing, parents are carefully selected until the planned positive result is obtained. And when the result is achieved, the hybrid is patented. At the same time, parental forms are usually kept secret. One of the parents does not always have the best characteristics from the point of view of the consumer of the fruit, but at the same time it may have unique abilities to withstand dangerous diseases. So when using the various characteristics of the parents when crossing, children can be "born" who inherited resistance to diseases from one parent and excellent yield from the other. Just like people. The fashion model declares - "I received a beautiful figure from my mother, and an expressive look from my father."

Sometimes F1 hybrids are superior to both parents in a number of positive traits. Breeders call such a miracle heterosis. And hybrids with such traits are called heterotic. On the package with seeds, this feature is certainly mentioned. Today, there are a huge number of hybrids that seriously compete with varieties in the seed market. The seeds of the hybrids are expensive, and the plants from them grow powerful, strong and abundantly fruitful.

Hybrid plants produce very few seeds compared to varieties. This is one of the reasons for their high cost. Vegetable growers - amateurs are advised to buy exactly expensive seeds, because in the end they will become cheap, bringing a plentiful and high-quality harvest. There is a lot more fuss with cheap seeds, and the end result is usually only satisfactory. Often there is a complete lack of harvest, as a result, unwisely purchased cheap seeds turn golden.

You should not save the seeds obtained from the hybrids for sowing for the next year. Since in the second generation there is a "scattering" of the positive characteristics of the hybrid into parental forms, the quality of which will not satisfy the vegetable grower for the reasons stated above. Which of them can grow, only the author of the hybrid knows.

BMW 7 Mild Hybrid ActiveHybrid: Electric motor assists the combustion engine

Full hybrid concept: the BMW X6 ActiveHybrid can rely entirely on its electric motor

The word "hybrid" comes from the Latin language and means something that is of mixed origin or combines dissimilar elements. In automotive technology, it refers to a vehicle with two types of powertrain. Usually this is an internal combustion engine and an electric motor.

In lightweight hybrid installations, the electric motor is used only as an auxiliary to the internal combustion engine (ICE). But in a full-fledged hybrid installation, the internal combustion engine is more efficiently paired with an electric motor. Moreover, the electric motor is used quite powerful, capable of independently driving the car at low speeds.

For modern automakers, a “hybrid car” means more than simply integrating an electric motor into a powertrain. This is "intelligent" control of the flow of energy in the car. An effective combination of internal combustion engines with electric motors reduces fuel consumption, exhaust toxicity, improves dynamics and driving comfort. A good example of this is the luxurious BMW 7 ActiveHybrid, which we talked about in the article "Active Hybrids". Today auto makers are developing five main varieties of hybrid vehicles.

Consistent... In such a hybrid system, the internal combustion engine operates in the most economical mode, solely in order to charge the battery of the electric motor. The car itself is driven by an electric motor.

Parallel... In such a hybrid, the internal combustion engine and the electric motor operate independently of each other, and, depending on the type (mild or full hybrid), they can drive the car simultaneously or in turn.

Soft... Here, the traditional starter and alternator are completely replaced by an electric motor, which is used to start and support the engine. This helps to increase vehicle dynamics and reduce fuel consumption by about 15%. The electric motor and batteries are not designed to propel the vehicle on their own. But this makes it possible to significantly lighten them and reduce the cost, in comparison with the components of a full hybrid. The BMW 7 ActiveHybrid is based on the mild hybrid concept.

Full... In fully hybrid systems, the car can be propelled by an electric motor at any stage of the movement: both when accelerating and when driving at a constant speed. For example, in a "city cycle", a car can use only one electric motor. The system components of such a concept are noticeably larger, more massive, and much more difficult to install than in the case of a "soft" hybrid. However, they can significantly improve vehicle dynamics. In addition, using only electricity when driving in the city can reduce fuel consumption by 20%. The full hybrid is the BMW X6 ActiveHybrid.

Rechargeable... The capacity, size and weight of the battery depends on its purpose. In recent years, new developments in this area have greatly expanded the applicability of batteries in automobiles. High capacity and durability make Li-Ion and Ni-MH power supplies fully suitable for use in hybrid vehicles.