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Plants as source of biologically active substances Plants are producers of many BAS – substances, capable to affect on biological processes in an organism. For ex., glycosides, saponins, sterols, carothenoids, polyphenols, alkaloids, vitamins, quinones, and also the substances possessing specific aroma, taste and coloring. Biologically active agents are products of a secondary methabolism which are called biosynthesis by-products. Now it is known more than 100 000 secondary metabolites produced by plants. Many of them are practically, economically important products and are used in the pharmacological, cosmetic, food industry. Plant product Plant species Codein (alcaloid) Papaver somniferum Diosgenin (steroid) Dioscorea deltoidea Quinin (alcaloid) Cinchona ledgeriana Digoxin (cardiosteroid) Digitalias lanata Scopolamin (alcaloid) Datura stramonium Vincristin (alcaloid) Catharanthus roseus Cell engineering of plants is considering various ways to get cell culture, cultivation of plant and animal cells, the selection of isolated protoplasts, biological engineering, and the creation of experimental systems association between cultured cells of higher plants and microorganisms. Cell technologies, based on in vitro cultivation of organs, tissues, cells and isolated protoplasts of higher plants, can facilitate and speed up the traditional breeding process. This, above all, the following technologies: the culture of ovules and embryos, the regeneration of plants from tissue lethal 1 hybrids, experimental haploids, cryopreservation of the gene pool, clonal micropropagation. Cell Engineering offers new ways for developing high plant shapes. This hybridization of somatic cell transfer of foreign genes. Ten most used medicinal substances, received from plants API Steroids from diosgenin Action Contraceptive Source plant Dioscorea deltoidea Codein Pain-killer Papaver somniferum Atropin Anticholinergic Atropa belladonna L. Reserpin Hipotensive Rauwolfia serpentina L. Hyosciamin Anticholinergic Hyoscyamus niger L. Digoxin Cardiac stimulant Digitalis lanata L. Scopolamin Anticholinergic Datura metel L. Digitoxin Cardio-vascular Digitalis purpurea L. Pilocarpin Cholinergic Pilocarpus jabonandi Chinidin Antimalarial Cinchona ledgeriana Examples of medicinal substances received on a basis of callus cultures Steviozid is natural sweetener and sugar substitute, is successfully used instead of artificial sweetening substances. Initial plant is Stevia rebaudiana Bertoni. Arglabin is antineoplastic substance. Initial plant is Artemisia glabella Kar. et Kir. Is a part of the preparation of the same name. Lappakonitin is diterpen alkaloid, antiaritmic. Initial plant is Aconitum septentrionale Koelle. Is a part of Allapinin's preparation 2 Genetic engineering of plants is not as well developed as in the case of animals and microbial cells. However, it is now attracting more and more attention, because it opens new opportunities in agriculture. The usual selection is a slow process and, in addition, it is limited by natural species barrier. The introduction of new genes using recombinat DNA technology could accelerate this process and to significantly expand its capabilities. Besides plants have significant feature - the whole plant can be grown from a single cell. This does not apply to all plants. For example, cells of cereals or legumes rarely undergo such redifferenciation, while the cells of tobacco, tomato or carrot, as shown, are redifferenciation relatively easy. When dissolving the cellulose of plant cell wall enzymes by celulases, protoplasts are formed. They can easily penetrate macromolecules, including DNA. Two different cells as protoplasts connected with the formation of protoplast fusion - somatic hybrid cells. Protoplasts are able to restore the cell wall and then give the whole plant. The plant can be obtained from protoplasts that have incorporated foreign DNA or hybrid protoplasts. If there are methods of introduction into plant cells of certain genes that are capable of functioning and stable inheritance, offers real opportunities to create plants with pre useful properties. Vectors to introduce genes into plant cells can be based on the replicons of plant viruses. However, to date, attempts to obtain such vectors satisfying, in particular the requirement of stable inheritance, were not very successful. Created transgenic canola containing the genes of individual human neuropeptides such as Leu-enkephalin gene-related albumin rapeseed. With one hectare of land sown with rape so, you can receive up to 3 kg of neuropeptide. A new variety of tomatoes, long lasting without softening due to the suppression of activity of the enzyme polihalacturonidase. 3 Such genetically engineered soybean varieties that are resistant to insects, herbicides, viruses, and produce more storage protein-enriched methionine was designed. Based on the methods of genomic engineering obtained interspecific hybrids of cabbage, potatoes and tobacco with turnips, potatoes with tomato - "Pomat" tomato wild species that is resistant to some viruses, and cultural variety. The world's first genetically engineering a chimeric plant "sanbin" received in the U.S. as a result of gene transfer bean storage protein gene in fazeolina sunflower. In 1984-87. Transgenic plants: tobacco, tomato, celery, alfalfa and cotton. The introduction of transgenic wheat genes that determine animal proteins (myosin) can bring bread to the quality of animal products. Introduction into a plant gene encoding the protein thaumatin (600 times sweeter than glucose), can improve the taste of many fruits, without increasing the carbohydrate content. In the United States are grown transgenic rapeseed, soybean, cotton, and herbicide-resistant, created transgenic tomatoes containing genes of tobacco mosaic virus, which makes them resistant to other viruses. Genetic engineering methods are introduced into the plant genome, genes encoding proteins that are toxic to many insects. So are plant varieties that are resistant to pests. Genetic engineering solves the problem of artificial food. Already, the bacteria enter the genes that control the synthesis of amino acids, the problem is a strain of yeast, bacteria that produce food proteins, and they are intended to cultivate sugar industry waste. Transgenic (or genetically modified) is a plant in which the gene by genetic engineering transferred genes (called "transgenic") from other organisms. Transfer process is called genetic transformation. The main advantages of this technology compared to conventional breeding are: the possibility of transfer of a single gene, which is practically not affect the original genotype, the ability to make the signs that can’t be transferred by mating with closely related species, and a significant acceleration of the acceleration of new genotypes. The most widely used method of transformation - Agrobacterium has been developed based on the natural process. The soil bacterium Agrobacterium tumefaciens to infect dicotyledonous plants, causing the tumor - the Gaulsspreader. As it turned out, and there are transfer and integration into the plant genome of two groups of genes: some products interfere with the normal metabolism of plants and contribute to the widening of the tumor, and other products synthesized opin substances unwanted plants, but are used as food by 4 bacteria. Scientists modified Agrobacterium so that they are instead transferred to a plant's own genes to the right person. Subsequently, a number of other methods of transforming plant cells, of which the most widely purchased bioballistic. It is used most often for genetic modification of monocots are unaffected by Agrobacterium. In special installations of gold or tungsten microparticles coated with DNA are accelerated by compressed gel, and they penetrate the target cell DNA. Symptoms, which may give them with the help of genetic engineering, are very diverse and mostly limited to the presence of the corresponding genes. Roughly speaking, they can be divided into three groups. The first is the features and interesting producers: resistance to various environmental factors - herbicides, diseases, pests, drought, salinity, improved mineral nutrition, rooting. The second group of features of interest directly to consumers - the modification of flavor and aroma of fruit, longer storage, change in color of flowers, seedlessness, improving the nutritional value of plants. The third group includes plants' biofactories "capable of synthesizing vaccines, enzymes, biopolymers and other useful substances. Cell Engineering produces varieties of plants under controlled conditions, as well as pharmaceutical preparations (ubiquinone-10-tobacco-yatrorrizin barberry, shikonin- lithospermum). Callus culture is disorganized proliferative tissue, consisting of differentiated cells. Callus (means corn) may be formed as isolated pieces of tissue explants, and the whole plant in the defeat. Callus tissue is amorphous and has no anatomical structure, and can be of different consistencies: 1. loose, consisting of strongly cell hydration, easily divided into separate loose agregates; 2. medium density with well-defined individual meristematic centers; 3. thick, in which the elements are differentiated cambium and conducting system. Obligatory condition of tissue dedifferentiation and turning it into callus is the presence in the medium of phytohormones: auxin and cytokinin. Auxins promote differentiation, and cytokinins cause proliferation. 5 Tumor cells, in contrast to the callus can grow on nutrient media lacking phytohormones (auxin, IAA, etc.). They cannot form normally organized vegetative organs. And in some cases, of which there may be ugly organ-like structure, so they cannot be applied breeding. Bacterial DNA exists not only in the form of chromosomes, but in the form of small circular molecules (plasmids). Bacterium Agrobacterium tumefaciens plasmids contain among others, causing tumors (Ti-plasmid). On this plasmid among other genes have an area of T-DNA containing the genes for tumor formation in plants and opine synthesis. It is this piece of Agrobacterium plasmid DNA inserted into plants. It turned out that, in principle, Agrobacterium can survive in any plant DNA, which is located at the site of plasmid. Therefore, in the plasmids used in genetic engineering purposes, natural substitute for any other genes of interest to the person. Typically, it is two to three genes: the target, which gives, for example, resistance to insects, selective, which confers resistance to certain substances (most often - antibiotics), which allows transformed cells to grow in a culture medium with antibiotics, while non-transformed cells in it are dying, and sometimes a reporter gene, which can qualitatively determine the transformed cells, such as painting or glow in ultraviolet light. Plant regeneration from callus based on totipotent. This phenomenon was discovered in the Gaberland’s laboratory. Totipotency - a property of somatic cells of plants fully realize its potential for the formation of the whole organism. Its essence is that if a plant cell is isolated, it behaves like the cells of the embryo sac that is formed embrioid and whole plant. Totipotency of cultured cells suggests that genetic information is stored. But its implementation requires specific conditions. Among the factors that could completely or at least partially restore the masked genetic information, are light, growth regulators, precursors and batteries. The stimulating effect of light on the formation of secondary compounds have been shown by the example of carotenoids, essential oils. Additionally important is the temperature, humidity, light and periodically update the medium, since the growth of the cells it accumulates metabolites that adversely affects the crop. therefore, this technique is associated with changes, i. e. with the transfer of part of the biomass to the new environment in another vessel ("passages"). When cultured plant cells have a low rate of reproduction than microbiological objects, so the duration of cultivation determined not tens of hours and tens of days. Method for growing cells in vitro is that the plant, isolated from any plant organ tissue (explant) is placed on the culture medium, the components of which are chosen so that they support the normal functioning of cells and stimulate the division. Therefore, these cells can be cultivated only in complex nutrient media containing salts of nitrogen. K, Mg, P and a number of trace elements, organic 6 substances - carbohydrates, amino acids, vitamins, hormones (kinetin, indoleacetic acid). Callus cells have different shapes. When callus in the membranes increases the content of saturated fatty acids, unsaturated and disappear, there is a process of differentiation, i. e. transition of cells to the level of the isolated cells. Callus can be obtained from a number of plant tissues. Young cells are more suitable for this purpose than mature, this is especially noticeable on the leaves. Pieces of the stem of trees is bad material for callus. Any type of plant callus provides, subject to certain methodological techniques of cultivation. In the cells of explants, consisting of specialized cells dividing at the beginning of cultivation can be observed changes in metabolism associated with traumatic synthesis, with dedifferentiation and prepare for the process of division. It can be assumed that the injury results in the release of cell biologically active substances - inducers of cell division, different in nature from the known growth factors (auxins, gibberellins). Clonal micropropagation is the use of in vitro techniques for rapid propagation of plants, identical to the original, asexually. The term "clone" (from the Greek - the son) was proposed Weber in 1903 in the study of vegetative propagation of plants. Clone is a collection of cells or individuals descended from a common ancestor by asexual reproduction - the basic unit of account in the genetics of microorganisms. At the heart of the formation of clones is mitosis, so it is believed that the clone is made from genetically homogeneous cells. However, this is very concerning because of spontaneous mutations. Only cloning can save particular grade. Clonal micropropagation is the way to obtain clones of plants by growing them from a single cell by totipotent cell culture. Clonal reproduction has many advantages and is very promising: 1. Clonal reproduction ratio is much higher than the usual methods of reproduction. So, from one plant gerbera a year you can get 50-100 plants in the usual way, in clonal propagation of tissue culture to 1 million 2. Plants can be propagated throughout the year. 3. Thousands of plants can grow in a relatively small area of the laboratory. 4. Along with breeding and improvement of plants are (from viruses and pathogens). 5. Clonal propagation method are planting plants that reproduce sexually slowly or not at all propagated vegetatively. 7 6. In clonal reproduction, as opposed to sexual reproduction, the offspring are genetically homogeneous. There are 2 types of clonal propagation: 1) small-scale (with selection works); 2) mass-clonal, commercial reproduction; a) the release of virus (potato); b) obtaining planting material (flowers, crops). When used as explants differentiated plant tissues may cause mutant forms. All manipulations in clonal micropropagation of plants carried out under aseptic conditions, that is in compliance with the microbiological technique works. Work is carried out or in microbiological boxes irradiated with UV light, or in a laminar box, where asepsis is achieved applying sterile air. The whole process of clonal micropropagation has a duration of about three months, and it can be divided into 4 stages. At the first stage, the choice of the donor plant, isolation and sterilization of explant and creating conditions for the formation of callus on solid medium. The second stage is associated with an increase in the number of initials on the callus formation and shoot. The third stage - the test-tube rooting propagated plants and their adaptation to the conditions in vitro. Fourth stage - growing plants taken from test tubes in a greenhouse and hardening before planting in the field. One of the major problems with the multiplication of the callus is a reduction in the callus growth. 8 Getting plants through organogenesis can be done in 3 ways: 1. By forming adventitious of callus derived from explants. 2. Through the formation of adventitious organs directly from explants without an intervening callus phase. 3. Through the formation of regenerated plants from shoots formed from the swollen buds. The main disadvantages of clonal micropropagation of plants: 1. Most of the complexity and high cost. The need to automate and radically new techniques. These include the failure of rooting plants in vitro and involvement of hydro-and aeroponics. Further progress will be linked to the automation and robotization of time-consuming procedures. 2. All specimens of this species occur from a single meristem and have reduced genetic diversity. Therefore, new diseases can be catastrophic for them by the same susceptibility to pathogens. Therefore, along with the development of vegetative propagation technique based on the culture of meristematic cells and is necessary to have a collection of seeds for conservation of genotypes necessary to maintain genetic diversity. 9 Cultivation of protoplasts Protoplast culture methods are consistent with those used for cell cultivation. Protoplasts were plated as a liquid and on solid medium of the same composition with different concentrations of agar. The main requirement for used means is that in the process of cultivation is no destruction of protoplasts and the environment was optimal for the formation of cell colonies. As long as the protoplasts did not form a cell wall, they are a very delicate structure and work with them should be carried out under mild conditions. The conditions in which the protoplasts are cultivated, mainly corresponding to those used for the cultivation of plant cells in culture. The content of mineral salts may change somewhat. As a rule, the medium should consist of physical stabilizer, inorganic compounds, carbon sources, vitamins, organic nitrogen sources and phytohormones. Mannitol, sorbitol, and their combination can be used as an osmotic stabilizer. The basis is the composition of mineral salts in the culture media of plant cells. You can change the ratio of ammonium and nitrate nitrogen, depending on the needs in their cells, increase the concentration of CaCl 2 to stabilize the resulting cell wall. Once formed and began to share cells, they can be placed in culture conditions usually used for plant cells. In the first days of cultivation a number protoplatov dies, which may be due to the heterogeneity of the population with respect to the action of osmolitikov. The remaining protoplasts within hours start to synthesize cell wall. This process is fully completed when the right conditions of isolation and culturing for 1-4 hours. In this case, the protoplasts lose spherical, elongated cells. The rate of regeneration of the cell wall depends on the plant species and tissues from which derived protoplasts, as well as on the degree of differentiation. Under adverse conditions, the isolation and culture of protoplasts cell walls are not formed on the entire surface. At the break out part of the protoplasm, being surrounded by the plasma membrane. It may be in the vacuole. This so-called kidney. "Budding" comes at an elevated concentration of osmotically active substances in the presence of unsuitable for the crop of sugar, with a low content of CaCl2, etc. When the right conditions for the isolation and cultivation of the third and fourth days after sowing observe the first division of the protoplasts. In most cases, then formed multicellular aggregates, developing later in the callus, which can regenerate the whole plant. Plant regenerates from protoplasts prepared now for alfalfa, tobacco, carrots, tomatoes and many other agriculturally important plants. Prospects of drugs based on plant cells 10 Advantages of a number of pharmacological agents from plants is as follows: • independence from climatic, seasonal and geographical conditions; • stability of output during the year; • reduction of the area of the soil involved in the economy. At the base of cell culture you can: • receive certain substances inherent in certain plants, such as nicotine, codeine, quinine, saponins, etc.; • to ensure the synthesis of new products difficult to grow plants such as ginseng adaptogen out; • receive a new substance; • use of cells for biotransformation of the final product. Currently, there are industrial production of several valuable compounds from plant biomass by in vitro. Well established in Japan, the release of such drugs: shikoin (vorobeynika of pharmacy), ubiquinone (from tobacco, digoxin (digitalis of woolly), diosgenin (Dioscorea deltoid). Industrial production of drugs on the basis of cultures, cells guarantee a good yield. This can be confirmed by comparing the output percent of the active ingredient of solid biomass feedstock taken in an equivalent amount. For example, preparation of anthraquinones from Cassia: • Biomass - 0.334% 0.209% whole plant dry weight; • diosgenin - a tuber, 26 mg per 1 g of dry weight, biomass - 26 g per 1 g of dry weight. In the 60's proved the ability of cells and tissues of plants to grow, divide, organoobrazovaniyu and secondary metabolism, ie the ability of any cell to form a complete plant, as genetic and physiological capacity for secondary metabolites present in every cell. For crops needed highly plant cell. Since the growth of Rhodiola rosea more promising are cells of root system. 11 For growth and synthesis of products of secondary metabolism requires the selection of ingredients of the culture medium, which is carried out in two directions and evaluate: - The impact of environment on the formation of biomass; - The impact of the environment on the synthesis of secondary products. The components of the growth medium plant cell cultures should include: basic inorganic nutrients, sources of iron, organic supplements (vitamins, growth regulators), a carbon source, as described above. There are several standard culture media, widely used in cultivation, but the amount of growth regulators in them varies depending on the type of plant. the yield can affect the concentration of the carbon source, and the other components of the environment. So in cell culture vinca alkaloids increased output was due to the increase in the concentration of sucrose in the medium, and the culture of carrot cells accumulate anthocyanins stabilized, when used as a limiting factor of the phosphate. As regulators of growth and synthesis of products of secondary metabolism using auxins, including indole-3-acetic acid, naphthylacetic acid, 2,4dichlorophenoxyacetic acid, and tsitohininy. The synthesis of secondary metabolites affect introduced into the medium quadrupeds predecessors, which can stimulate certain enzymatic pathways. Since the introduction of phenylalanine in the cell culture medium increased the yield of diosgenin by about 100%. The degree of accumulation of secondary metabolites are also affected by light, temperature, pH, and with a suspension suspending cultivation - aeration and agitation speed vessels, gas composition, etc. Thus creating for each plant cell culture facilities at the growth stage and the synthesis of secondary metabolites, it is possible to guarantee receipt of any product from metabolic activity. For the accumulation of industrial raw materials by growing the cells and tissues of plants using callus and suspension cultures, the latter derived from the callus. Technology for producing plant material based on callus culture has several advantages - reliability and stability of the biomass yield and the products of secondary metabolism, as well as the use of callus for immobilization and subsequent biotransformation, but has a significant drawback - the need manual labor. In Russia, the technology for production of substances of ginseng, Rhodiola rosea, Unger based on callus cultures. These drugs have been used in medicine, 12 cosmetics and food industry. With the implementation of suspension cultivation is necessary to consider the basic properties of plant cells: plant cells are 50-100 times greater than the fungal cells, resulting in the growth of the cells increase in size, they appear large vacuole, suspension cultures consist of cell aggregates, the presence of the cellulose cell wall , respiratory rate. Growing plant cells are in the blood vessels of various sizes (up to 200 liters) with a stirring system (turbines, rising air, shaking). Currently, multi-step process used to produce biomass and products of secondary metabolism: - Growing in aerated reatore; - The transfer of cells from one medium to another, richer micro-and macro nutrients, but devoid of organic additives; , The subsequent addition of cycle organics. In general, cells are grown in a batch reactor. To increase the yield of products of secondary metabolism are developed in relation to methods of immobilization plant cells, biotransformation. On some models, cell cultures, for example, corn has been shown that the synthesis and accumulation of secondary metabolites related to the state of aggregation, it is noted that the closer the cells and groups of cells to the whole plant, the higher their metabolic potential. However, there is a lot of data about the inverse relationship between the state of aggregation and accumulation of secondary metabolites. This is due to two types of mechanisms. The first is based on the fact that determines the level of aggregation of cells, and it is sufficient power can be achieved in a slow-growing cultures. The second mechanism is related to the kinetics of the growth rate and suggests that the primary and secondary metabolic pathways in different ways compete for precursors in the fast-and slow-growing cells. On the basis of the above, it is clear that immobilized cells with a low rate of growth, the ability to efficient generation of metabolites. One of the conditions for the immobilization of cells - a metabolite excretion into the medium from which it can be easily removed. These cultures are cells that produce alkaloids. The advantages of immobilized cells compared to suspension cultures are: - Repeated use of biomass; - Clear separation of biomass from metabolic products; - Increasing the duration of cultivation stage production; - Getting a large number of secondary metabolites. 13 Another promising way of using plant cell cultures in the pharmaceutical industry should consider their application for the biotransformation. Biotransformation - a method that uses enzymes that are localized in the plant cell, which are able to change the functionality of the added external chemicals. This method is suitable for increasing the biological activity of the specific chemical structure and the implementation of a series of specific chemical reactions by including one or more consistently related enzymes. Possibility of biotransformation in the synthesis of some compounds has been shown on the conversion of digitoxin to digoxin cells Digitalis lanata (woolly foxglove). After a 10-day incubation D.lanata in "growth" medium (Murashige and Skoog) cell culture was transferred to "a production" environment (8% glucose) with the substrate for the biotransformation - digitoxin. Under these conditions all digitoxin for 2 days was transformed into deatsetillantozid C (digoxin) and purpurglikozid A 88% and 12% respectively. Digitoxin and digoxin belongs to the group "cardenolides" used for the treatment of chronic heart disease. Currently These compounds are in sixth and eighth place in the list of the most common drugs in United States, but the use of digoxin is preferred because of its lower toxicity compared to that of digitoxin. Both compounds in the U.S. is produced by extracting the plantation grown plants, but it stands out mainly digitoxin. Undifferentiated culture do not form Digitalis cardiac glycosides, but can perform certain biotransformation reactions of substrates that have been added to the culture medium. Biotransformation of digitoxin to digoxin is due to the 12hydroxylation reaction catalyzed by an enzyme found in the cells of Digitalis lanata. The work was carried out using free undifferentiated suspension cultures in Germany in 1977, and to date, put into production, made out of digoxin within the 700 g / L in 20-liter reactor within 17 days of cultivation. Thus, the major problems associated with the biotransformation of cardiac glycosides Digitalis lanata cells currently allowed. However, further development of this area should be further selection of specialized cell lines and optimization of the conditions of cultivation, reducing fermentation time and extend the life of cells. Basic conditions for the transfer of laboratory methods of cultivation of plant cells in industrial production is economically viable and relatively simple technology of cell culture and isolation of the final products. For example, production aymalina through meristem culture Rauwolfia became real when, in the course of breeding and selection were obtained subclones of cells that synthesize this alkaloid is much higher than the original parent strains. 14 Production based on the serpentine suspension cultures partially differentiated cells meristem Catharatus roseus was effective and economically justified only after received subclones able to accumulate over 10 daily cycle of growing up to 25 g of dry matter per 1 liter of suspension culture. A similar situation took place in the organization of the biotechnological production of tincture of ginseng. Yield of the biological substance in terms of dry matter ginseng callus was lower than that of ginseng obtained by plantation cultivation, about 3-4 times. Production of bio-ginseng has become economically viable only after it was possible to increase the productivity of callus cultures, keeping unchanged reactogenic properties extracted medicinal tinctures. It turned out that the more differentiated cells in the meristem culture, the higher their productivity. The technology of the culture of so-called "bearded" roots, where growth conditions in a cluster of cells arise subpopulations with increased differentsirvkoy. These populations are the most productive on biologically active substances. VECTORS genetic engineering of plants In genetic engineering of plants are used as vectors Ti-plasmid constructed by Agrobacterium Agrobacterium tumifaciens, and Gauls-spreader Natural Ti-plasmid system of gene transfer in plants needs to be modified before it can be used. Universal vector system based on the T-DNA should: a) contain all the signals necessary for the transfer and stable integration into the nuclear DNA of plants, all of the products required for these processes, a system for the expression of genes transferred into plants, a marker that helps selecting transformed cells; b) contains functions that can affect cell differentiation and regeneration of plants; c) describe a simple method of introducing foreign DNA into the vector; d) to have reliable methods for introducing Ti-plasmid sequences of the cloned alien X-gene into the plant; 2. Transposed elements (TE). Are segments of DNA that are autonomously control their own exposure (cut) from the chromosome and integration of the new site of DNA. 3. Plant viruses. 15 Another possibility is the construction of vectors associated with the use of plants phytoviruses and viroids. Because with recombinant nucleic acids are easier to manipulate DNA, the real candidates for becoming kaulinovirusy vectors containing double-stranded DNA geminiviruses containing single-stranded DNA. DNA viruses that are present only these two groups account for only 1-2% of the total number of viruses infecting plants. Modern herbicides are much more efficient and environmentally safer than their predecessors, but they operate on the vegetation succession, not understanding where the crop plants, where the weeds, so earlier is mainly used to planting or after harvest. With the advent of genetic information has become possible to build into the plant genes that make them insensitive to these herbicides. Thus, after herbicide treatment weeds are killed, and transgenic crops no. To give resistance to pests most commonly used Bt-toxin gene, isolated from the bacterium Bacillus thuringiensis. Preparations of this bacteria for about 50 years used in agriculture as a safe for humans and animals bioinsecticides, but they quickly lose their activity, and therefore, their share in world production of insecticides is not more than 2%. The toxin affects the gut bacteria pests that feed on plants, and with very high specificity. By incorporating a gene plant begins producing the toxin itself. So, no need to handle hazardous chemicals, crop insecticides. Questions for self-checking: 1. What type of metabolites of plants are alkaloids? 2. What are the chemical structures of the most technologically receive with the help of vegetable producers? 3. name the basic biotechnological form vegetable producers; 4. name the main reasons for the need for the development of biotechnological plant producers. 16