How chemicals affect plant growth. Influence of various substances on the growth and development of plants. The influence of humates on the biological properties of soils
COURSE WORK
Influence various kinds seed treatment for plant growth and development
Introduction
The issue of presowing seed treatment, despite numerous studies, remains relevant and open so far. Interest is generated by the prospect of using various types of seed treatment in agriculture in order to increase plant productivity and obtain a higher yield.
During storage, the seeds age, the quality and germination of seeds decrease, therefore, in a batch of seeds stored for several years, there are strong seeds, weak (live, but not germinating) and dead seeds. Known methods of pre-sowing seed treatment, which can increase the germination of seeds lost during storage. Ionizing radiation in small doses, sounding, short-term thermal and shock-wave treatments, exposure to electric and magnetic fields, laser irradiation, presowing soaking in solutions of biologically active substances, and others can increase seed germination and yield by 15-25%.
As you know, to increase productivity mineral fertilizers, it is convenient to introduce them into the soil, this process is mechanized. The use of mineral fertilizers causes accelerated plant growth and increased yields. However, nitrates and nitrites, which are not dangerous for plants, but dangerous for humans, are often formed in parallel. In addition, there are more serious consequences of the use of mineral fertilizers associated with changes in soil structure. As a result, fertilizers are washed out from upper layers soils to the lower ones, where the mineral components are no longer available to plants. Then mineral fertilizers fall into ground water and are carried to surface water bodies, significantly polluting the environment. The use of organic fertilizers is more environmentally friendly, but they are clearly not enough to meet the human need to increase productivity.
Ecologically safe physical methods of seed biostimulation are very promising. At present, it has been experimentally proven that biological objects are able to sensitively respond to the impact of external electromagnetic fields. This reaction can occur at various structural levels of a living organism - from molecular and cellular to the organism as a whole. Under the influence of electromagnetic waves of the millimeter range in the cells of biological objects, the processes of biosynthesis and cell division are activated, connections and functions disturbed due to diseases are restored, substances that affect the immune status of the body are additionally synthesized.
To date, a large number of various irradiation installations and methods for activating seeds have been developed. However, they are not widely used, although compared with by chemical means they are more technologically advanced, environmentally friendly and much cheaper. One of the reasons for this situation is that the existing methods of treating seeds with radiation do not give consistently high results. This is due to the fact that in the existing methods of pre-sowing treatment, the qualitative and quantitative characteristics of radiation are not optimized.
Purpose of the study - to study the influence of various types of pre-sowing seed treatment on the growth and development of plants.
In this regard, the following tasks :
study the influence chemical substances on the growth and development of plants;
· to study the influence of electromagnetic (biophysical) treatment on growth processes in plants;
· reveal the effect of laser irradiation on the germination of barley seeds.
1. Pre-sowing seed treatment and its effect on plant growth and development
1.1 Effect of chemicals on plant growth and development
barley seed laser irradiation
The most important and effective part of the treatment is the chemical or seed dressing.
4 thousand years ago in Ancient Egypt and Greece, the seeds were soaked in onion juice or shifted during storage with cypress needles.
In the Middle Ages, with the development of alchemy and, thanks to it, chemists began to soak the seeds in rock and potash salt, blue vitriol, salts of arsenic. In Germany, the most popular were simple ways- keeping seeds in hot water or in manure solution.
At the beginning of the 16th century, it was noticed that seeds that had been in sea water during a shipwreck produced crops that were less affected by hard smut. Much later, 300 years ago, the effectiveness of pre-sowing chemical seed treatment was scientifically proven in the course of the experiments of the French scientist Thiele, who investigated the effect of seed treatment with salt and lime on the spread through the seeds of hard smut.
At the beginning of the 19th century, the use of preparations with arsenic as dangerous to human life was prohibited, but at the beginning of the 20th century they began to use mercury-containing substances, which were banned for use only in 1982, and only in Western Europe.
It was only in the 1960s that systemic fungicides for pre-treatment of seeds were developed, and industrialized countries began to actively use them. Since the 90s, complexes of modern highly effective and relatively safe insecticides and fungicides have been used.
Depending on the technology of seed treatment, three types of seed treatment are distinguished: simple dressing, drageeing and encrusting.
Standard dressing is the most common and traditional way of seed treatment. Most often used in home gardens and farms, as well as in seed production. Increases the weight of seeds by no more than 2%. If the film-forming composition covers the seeds completely, their weight can increase up to 20%.
Encrusting - the seeds are covered with sticky substances that ensure the fixing of chemicals on their surface. Treated seeds can become 5 times heavier, but the shape does not change.
Coating - substances cover the seeds with a thick layer, increasing their weight up to 25 times and changing the shape to spherical or elliptical. The most "powerful" drageeing (pelletizing) makes the seeds up to 100 times heavier.
For the treatment of seeds of grain crops, the preparations Raxil, Premix, Vincite, Divident, Colfugo Super Color are most actively used. These are systemic fungicides that kill spores of stone, dusty and hard smut, nematodes that effectively fight Fusarium, Septoria and root rot. They are produced in the form of liquids, powders or concentrated suspensions and are used for seed treatment in special devices at the rate of 0.5-2 kg per 1 ton of seeds.
In private and farm households, the use of strong chemicals is not always justified. Relatively small quantities of small seeds of vegetable or ornamental crops, such as marigolds, carrots or tomatoes, can be treated with less toxic substances. It is important not only and not so much to initially destroy the entire infection on the seeds, but to form in the plant resistance to diseases, that is, stable immunity, even at the seed embryo stage.
At the beginning of germination, growth stimulants are also beneficial, which will encourage the development of a large number of lateral roots in plants, creating a strong root system. Plant growth stimulants, which enter the embryo before germination, cause active transport nutrients in the aerial parts of the plant. Seeds treated with such preparations germinate faster, their germination increases. Seedlings become more resistant not only to diseases, but also to temperature extremes, lack of moisture and other stressful conditions. More distant consequences of proper pre-treatment with pre-sowing preparations are considered to be an increase in yield and a reduction in ripening time.
Many preparations for pre-sowing seed treatment are created on a humic basis. They are a concentrated (up to 75%) aqueous solution of humic acids and humates, potassium and sodium, saturated with the complex needed by the plant minerals, which can also be used as a fertilizer. Such preparations are produced on the basis of peat, being its water extract.
Z.F. Rakhmankulova et al. studied the effect of presowing seed treatment of wheat (Triticum aestivum L.) with 0.05 mm salicylic acid (SA) on its endogenous content and the ratio of free and bound forms in the shoots and roots of seedlings. During two weeks of seedling growth, a gradual decrease in the total SA content in shoots was observed; no changes were found in the roots. At the same time, there was a redistribution of SA forms in the shoots - an increase in the level of the conjugated form and a decrease in the free form. Presowing treatment of seeds with salicylate led to a decrease in the total content of endogenous SA both in the shoots and in the roots of seedlings. The content of free SA decreased most intensively in shoots, and somewhat less in roots. It was assumed that such a decrease was caused by a violation of SA biosynthesis. This was accompanied by an increase in the mass and length of shoots and especially roots, stimulation of total dark respiration, and a change in the ratio of airways. An increase in the proportion of the cytochrome respiration pathway was observed in the roots, and an increase in the share of the alternative cyanide-resistant pathway was observed in the shoots. Changes in the antioxidant system of plants are shown. The degree of lipid peroxidation was more pronounced in shoots. Under the influence of SA pretreatment, the content of MDA in the shoots increased by 2.5 times, while in the roots it decreased by 1.7 times. It follows from the presented data that the nature and intensity of the effect of exogenous SA on growth, energy balance, and antioxidant status of plants can be associated with changes in its content in cells and redistribution between free and conjugated SA forms.
E.K. Eskov in production experiments studied the effect of presowing treatment of corn seeds with iron nanoparticles on the intensification of growth and development, increasing the yield of green mass and grain of this crop. As a result, there was an intensification of photosynthetic processes. The content of Fe, Cu, Mn, Cd, and Pb in maize ontogenesis varied widely, but the adsorption of Fe nanoparticles at the initial stages of plant development affected the decrease in the content of these chemical elements in the ripening grain, which was accompanied by a change in its bio- chemical properties.
Thus, pre-sowing treatment of seeds with chemicals is associated with at great expense labor and low manufacturability of the process. In addition, the use of pesticides for the purpose of disinfecting seeds causes great harm to the environment.
1.2 Effect of electromagnetic (biophysical) treatment on growth processes in plants
In the context of a sharp increase in the cost of energy carriers, technogenic pollution of agroecosystems, it is necessary to search for environmentally friendly and economically beneficial material and energy resources as an alternative to expensive and environmentally unsafe means of increasing productivity while improving the quality of crops.
Existing methods and technological methods of pre-sowing stimulation of seeds, based on the use of highly toxic chemicals, are associated with high labor costs and low manufacturability of the seed treatment process. In addition, the use of pesticides for the purpose of disinfecting seeds causes great harm to the environment. When seeds treated with fungicides are introduced into the soil, pesticides under the influence of wind and rain are carried into water bodies, spread over vast areas, which pollutes the environment and harms nature.
Of greatest interest for obtaining environmentally friendly products are the physical factors of the electromagnetic field, such as gamma radiation, x-rays, ultraviolet, visible optical, infrared, microwave radiation, radio frequency, magnetic and electric field, exposure to alpha and beta particles, ions of various elements, gravitational effects, etc. The use of gamma and X-ray irradiation is dangerous for human life, and therefore unsuitable for use in agriculture. The use of ultraviolet, microwave and radio frequency irradiation causes problems during operation. Relevant is the study of the impact of electromagnetic fields in the cultivation of cereals, nightshade, oilseeds, legumes, melons and root crops.
The action of magnetic fields is associated with their effect on cell membranes. The impact of the dipole stimulates these changes in the membranes, enhances the activity of enzymes. In addition, it has been established by other authors that as a result of such treatment, a number of processes occur in the seeds, leading to an increase in permeability. seed coats, accelerates the flow of water and oxygen into the seeds. As a result, it intensifies enzymatic activity, primarily hydrolytic and redox enzymes. This ensures a faster and more complete supply of nutrients to the embryo, acceleration of the rate of cell division and activation of growth processes in general. In plants grown from treated seeds, the root system develops more intensively and the transition to photosynthesis is accelerated, i.e. a solid foundation is created for the further growth and development of plants.
All this contributes to the vegetative process, accelerates its growth.
New nanotechnologies of microwave pre-sowing seed treatment and pest control were carried out as an alternative to chemical methods. For the disinsection of grain and seeds, a pulsed microwave treatment mode was used, which, due to the ultra-high intensity of the EMF in the pulse, ensures the death of insect pests. It has been established that for a 100% effect of microwave disinsection, a dose of no more than 75 MJ per 1 ton of seeds is required. But today these technologies cannot be used directly in the agro-industrial complex, since only their development is underway, and the estimated cost of introducing them into production is very high. Among the promising agricultural practices that have a stimulating effect on the growth and development of plants, one should include the use of electric and magnetic fields, which are used both in the pre-sowing preparation of seeds and during the growing season of plants by increasing the resistance of plants to stress factors, increasing the utilization factor of nutrients substances from the soil, which leads to an increase in crop yields. The positive influence of the electromagnetic field on the sowing and yielding qualities of seeds of grain crops has been proved.
Electromagnetic seed treatment, in comparison with a number of other methods of treatment, is not associated with labor-intensive and expensive operations, does not have a harmful effect on maintenance personnel (such as chemical or radionuclide treatment) or the use of pesticides, does not give lethal to seed doses, is a very technological and easily automated process, the impact is easily and accurately dosed, is environmentally friendly clean view processing, easily fits with currently used agricultural practices. It is also important that plants grown from treated seeds do not have further pathological changes and induced mutations. It is shown that the impact of an electromagnetic field increases the number of productive stems, the number of spikelets, the average length of plants and spikes, increases the number of grains in the spike and, accordingly, the mass of the grain. All this leads to an increase in yield by 10-15%.
G.V. Novitskaya studied the effect of a weak constant horizontal magnetic field (CMF) with a strength of 403 A/m on the composition and content of polar and neutral lipids and their constituent FAs in the leaves of the main magnetic-orientation types (MOT) of radish (Raphanus sativus L., var. radicula D. C.) varieties Pink-red with a white tip: north-south (NS) and west-east (WE), in which the planes of orientation of the root furrows are located along and across the magnetic meridian, respectively. Under the action of PMF in spring, the total content of lipids in the leaves of the NS MOT decreased, while in the leaves of the WE MOT it increased; in autumn, on the contrary, the total content of lipids in the leaves of SL MOT increased, while that of WE MOT decreased. In spring, the ratio of phospholipids to sterols, indirectly indicating an increase in the fluidity of the lipid bilayer of membranes, increased in plants of both MOTs, while in autumn it increased only in CL MOTs. The relative content of unsaturated fatty acids, including linolenic and linoleic acids, in the control was higher in SR MOT compared to NC MOT. Under the action of PMP, the content of these acids in the lipids of the leaves of the SL MOT increased, while that of the WE MOT remained unchanged. Thus, weak horizontal PMF differently, sometimes oppositely, affected the content of lipids in the leaves of SN and WE MOT of radish, which, apparently, is caused by their different sensitivity to the action of the field, associated with the peculiarities of their physiological status.
In addition, G.V. Novitskaya et al. studied the effect of PMF with a strength of 403 A/m on the composition and content of polar (head) and neutral lipids and their constituent fatty acids isolated from 3, 4 and 5 leaves of onion plants (Allium sera L.) cv. using TLC and GLC methods. Plants grown in the natural magnetic field of the Earth served as control. Under the action of PMF, the greatest changes in the lipid content were found in the fourth leaf of the onion: the total content of lipids increased, in particular, polar lipids (glyco- and phospholipids), while the amount of neutral lipids decreased or remained unchanged. The ratio of phospholipids/sterols increased, indicating an increase in the fluidity of the lipid bilayer of the membranes. Under the influence of PMP, the proportion of linolenic acid increased, and the relative content of the total unsaturated fatty acids also increased. The effect of PMP on the composition and lipid content of the third and fifth onion leaves was less pronounced, which indicates a different sensitivity of onion leaves of different ages to the action of the field. It is concluded that changes in the weak PMF within the past evolutionary-historical changes in the strength of the Earth's magnetic field can affect bio chemical composition and physiological processes in plants.
In the course of studies on the influence of an alternating magnetic field (AMF) with a frequency of 50 Hz on the dynamics of the deployment of cotyledon leaves, the composition and content of polar and neutral lipids and their constituent fatty acids in 5-day-old radish seedlings grown in light and in the dark ( Raphanus sativus L. var. radicula D.L.) variety Rose-red with a white tip, it was found that PMF weakened the inhibitory effect of light on the dynamics of cotyledon leaf unfolding. In the light in PMP, the total content of lipids, the content of polar and neutral lipids in the seedlings was higher than in the control. Among polar lipids, the total content of glyco- and phospholipids increased; among neutral lipids, the content of triacylglycerols increased. The ratio of phospholipids to sterols (PL/ST) increased. In the dark, in PMF, the total content of lipids, as well as neutral lipids in seedlings, was lower than in the control, and the PL/ST ratio decreased. In the control, no differences were found in the relative total content of unsaturated fatty acids in the light and in the dark; the content of linolenic acid in the seedlings was higher in the light than in the dark. Under the action of PMF, the content of linolenic acid in the light decreased, increased in the dark, and erucic acid decreased in the light. The ratio of unsaturated to saturated fatty acids decreased both in the light and in the dark. It is concluded that PMF with a frequency of 50 Hz significantly changed the lipid content in radish seedlings in the light and in the dark, acting as a corrective factor.
Thus, the studies of many authors have established that under the influence of an electromagnetic field, forces are mobilized and the energy reserves of the body are released, physiological and biochemical processes are activated at the early stages of seed germination, there is an increase in intra-metabolic processes and a steady increase in germination energy, germination, strength, initial growth, spring-summer survival, which favorably affect the entire subsequent period of plant development.
However, they have not received wide distribution, although they are more technologically advanced, environmentally safe and much cheaper compared to chemical methods. One of the reasons for this situation is that the existing methods of treating seeds with radiation do not give consistently high results. This is due to changes in external conditions, heterogeneity of the seed material and insufficient knowledge of the essence of the interaction of seed cells with electromagnetic fields and electric charges.
1.3 Effect of laser irradiation on plant growth and development
Since ancient times, the improvement of soil fertility has rightly been considered the most important condition for increasing the productivity of crop production. Huge amounts of money and efforts of scientists all over the world are spent on land reclamation, irrigation and chemicalization of agriculture. However, the sad paradox of progress in the chemicalization of agriculture is that after the excessive use of nitrates, phosphates, pesticides, synthetic growth regulators, an evil shadow follows the poisoning of crops, food, water, a threat to human health and life. Hence, as a consequence, there is an intensification of the development of new ways and methods of intensifying the productivity of crop production.
In the form of one of these methods, a laser or laser radiation is presented. Since modern scientific centers have begun to pay great attention to modern technologies growing crops, then in such conditions a number of methods have been developed for influencing crops with various physical factors that have a stimulating effect on the growth and development of plants and, ultimately, on the yield of the crops themselves. Plants or their seeds began to be placed in strong magnetic or electric fields, affect cultures with ionizing radiation or plasma, as well as irradiating concentrated sunbeam- light of modern artificially created radiation sources - lasers.
The action of laser processing as a whole can be called specific, since it is a positive factor in terms of ecology and safety for environment, since no foreign elements are introduced into nature during its action.
The method of exposure to a laser concentrates a sufficient number of advantages compared to other existing physical and chemical methods of pre-sowing seed preparation, namely:
1) a stable increase in crop yields against the background of various soil and climatic conditions;
2) improving the quality of agricultural products (increasing sugars, vitamins, protein and gluten content);
3) the possibility of reducing the seeding rate by 10-30% by increasing the field germination of seeds and enhancing growth processes (depending on the variety, type of crop, frequency of processing);
4) increasing the resistance of plants to damage by various diseases;
5) harmlessness of processing for seeds and service personnel.
However, the positive effect of laser irradiation of seeds and plants also has a share of disadvantages that must also be taken into account. Thus, the magnitude of the activation effect and its reproducibility depend on the condition of the seeds, which is influenced by many natural and uncontrollable factors during storage and irradiation. In addition, under certain conditions, irradiation of seeds with optimal doses may not affect plant activity at all and even have a depressing effect.
F.D. Samuilov studied the microviscosity of the aqueous medium in the embryos and endosperm of corn (Zea mays L.) seeds irradiated using a Lvov-1 electronics laser using a spin probe. According to the parameters of the EPR spectra of nitroxyl radicals (probes) absorbed by the seeds with water during swelling, the correlation times of the rotational diffusion of the C probe in the embryos and endosperm of the seeds were determined. A decrease in C of the probes in the embryos of irradiated seeds compared to non-irradiated seeds was found, and the dependence of the C value on the time of seed swelling was established. It is concluded that in the cells of seed embryos under the action of laser irradiation, the microviscosity of the aqueous medium decreases and the mobility of the probes increases. The effect of irradiation on C probes in the seed endosperm is manifested to a lesser extent and is also accompanied by an increase in probe mobility.
Thus, the laser treatment method has a number of advantages over physical and chemical methods of pre-sowing seed preparation. These include: improving the quality of agricultural products (increasing sugars, vitamins, protein and gluten content); the possibility of reducing the seeding rate by 10-30% by increasing the field germination of seeds and enhancing growth processes; harmlessness of processing for seeds and service personnel; short duration of exposure. But laser seed treatment is very expensive and therefore not widely used on the farm. Gamma irradiation makes it possible to accelerate the germination of seeds of some cultivated plants, increases field germination and the number of productive stems and, as a result, yields (up to 13%). The disadvantages include the dependence of the effectiveness of presowing irradiation on weather conditions during the growing season, a negative impact on a number of economic traits of plants, and a decrease in the intensity of the respiratory regime of plants. The main disadvantage this method stimulation is that increasing the dose of treatment can cause death.
2. Objects and methods of research
The research was carried out at the Department of Botany and Fundamentals of Agriculture, Belarusian State Pedagogical University. M. Tanka and the Faculty of Physics of BSU.
2.1 Object of study
The object of the study is the seeds of barley variety Yakub. This variety of Belarusian selection, obtained by the Republican Unitary Enterprise "Scientific and Practical Center of the National Academy of Sciences of Belarus for Agriculture" and included in the State Register in 2002.
Morphological featuresvarieties. A plant in the tillering phase of an intermediate type. The stem is up to 100 cm high. The position of the ear is semi-erect. The spike is two-row, cylindrical, up to 10 cm long, with 26-28 spikelets per spike. Awns of medium length in relation to the ear. Filmy grain. The ventral groove is not pubescent. The aleurone layer of the caryopsis is slightly colored. Type of development - spring.
Economic and biological characteristicsvarieties. Cereal variety. Grain size - high (weight of 1000 grains - 45-50 g). High-protein variety (average protein content 15.4%, protein yield per hectare up to 6.0 q). Medium late variety. Average yield - 42.3 q/ha , m the maximum yield of 79.3 c/ha was obtained at the Shchuchinsky GSU in 2001. Moderately resistant to lodging and drought. Disease resistant. High demands on growing conditions. High responsiveness to fungicides. Medium sensitivity to herbicides.
2.2 Research methods
Research methods - experiment, comparison method.
The experience was based on the following options:
1) control (seeds without treatment);
2) seed treatment with 660 nm waves for 15 min;
3) seed treatment with 660 nm waves for 30 min;
4) treatment of seeds with waves of 775 nm for 15 minutes
5) seed treatment with 775 nm waves for 30 min.
In options 2-5, the power of laser exposure (P) is 100 mW.
Seed treatment was carried out on laser systems (Figure 2.2).
The repetition of experience 3-fold. The number of seeds in repetition - 20 pcs.
Under laboratory conditions, the germination and energy of seed germination were determined. To do this, the seeds of grain crops were germinated at a temperature of 23 about C for 7 days.
Definition insimilarities of barley sprouts. Germination was determined in order to establish the number of seeds capable of producing normally developed seedlings. In normally developed seedlings, the germinal root must be at least half the length of the seed. To calculate the germination of seeds of one sample, the number of normally germinated seeds is summed up when germination is taken into account and their total number is expressed in%. In the course of this experiment, seedlings were counted quantitatively from the same sites on the 7th day.
Determination of the energy of germination. Germination energy was determined in one analysis with germination, but normally germinated seeds were counted on the 3rd day.
In normally developed seedlings, the germinal root must be at least the length or diameter of the seed and usually with root hairs, and the sprout must be at least half the length of the seed. Those species that germinate with several roots (barley, wheat, rye) must have at least two roots.
3. Effect of laser irradiation on the growth rates of barley seeds
As a result of the study, the selective nature of the laser effect on the growth rates of barley seeds, namely, the germination energy and germination, was established. As a rule, the condition of the seed determines the quantity and quality of the crop.
Germination energy characterizes the friendliness and speed of seed germination. Germination energy is the percentage of normally germinated seeds in a sample taken for analysis.
The results of our research showed (Figure 3.1) that the germination energy of barley seeds was the highest when exposed to laser irradiation at a wavelength of 775 nm for 30 minutes. Compared with the control, it increased by 54% and amounted to 54%.
Seeds irradiated with the same wavelength, only for 15 minutes, had a lower germination energy - 27%. This is lower than the control results by 1.3 times.
Seeds irradiated with a wavelength of 660 nm had a lower germination energy when irradiated for 30 min. Compared with the control, it decreased by 77% and amounted to 8%. When irradiated with the same wavelength, but for 15 min, this indicator also decreased compared to the control by 46% and amounted to 19%.
Seed germination is one of the important indicators of their sowing qualities. A decrease in germination even by 10-20% leads to a two-three-fold decrease in yield.
During the research, it was found adverse effect laser treatment for laboratory germination of barley seeds (Figure 3.2).
The most depressing was the treatment with waves with a length of 660 nm for 30 min. In this variant, compared with the control (85%), the germination rate decreased by 75% and amounted to 21%. When seeds are irradiated with the same wavelength, but for 15 minutes, an increase in germination is observed, but it does not exceed the control value. This indicator is lower than the control by 18% and amounted to 70%.
Treatment of seeds with waves of 775 nm reduced their germination by 33% (exposure 15 min) and 25% (exposure 30 min) compared to the control.
Thus, laser treatment did not have a positive effect either on the germination energy of seeds of barley cv. Treatment with 660 nm rays for 30 minutes had the most depressing effect on seed germination.
Conclusion
Thus, having studied the literature on this topic, we can draw the following conclusions:
1. Pre-sowing treatment of seeds with chemicals is associated with high labor costs and low manufacturability of the process. In addition, the use of pesticides for the purpose of disinfecting seeds causes great harm to the environment.
2. Under the influence of the electromagnetic field, forces are mobilized and the energy reserves of the body are released, physiological and biochemical processes are activated at the early stages of seed germination, there is an increase in intra-metabolic processes and a steady increase in germination energy, germination, strength, initial growth, spring-summer survival, which are favorable affect the entire subsequent period of plant development. However, they have not received wide distribution, although they are more technologically advanced, environmentally safe and much cheaper compared to chemical methods. One of the reasons for this situation is that the existing methods of treating seeds with radiation do not give consistently high results. This is due to changes in external conditions, heterogeneity of the seed material and insufficient knowledge of the essence of the interaction of seed cells with electromagnetic fields and electric charges.
3. The laser treatment method has a number of advantages over physical and chemical methods of pre-sowing seed treatment:
Improving the quality of agricultural products (increase in sugars, vitamins, protein and gluten content);
· the possibility of reducing the seeding rate by 10-30% by increasing the field germination of seeds and enhancing growth processes;
Harmlessness of processing for seeds and service personnel;
increasing the resistance of plants to damage by various diseases;
The short duration of the impact
· an increase in the germination of seeds of some cultivated plants, field germination and the number of productive stems and, as a result, productivity (up to 13%).
The disadvantages of this method include:
· dependence of the efficiency of presowing irradiation on weather conditions during the growing season;
· a negative impact on a number of economic characteristics of plants, a decrease in the intensity of the respiratory regime of plants;
· an increase in the dose of treatment can cause death;
very expensive and therefore not widely used in the economy.
4. Based on the results of our research, we can draw the following conclusions:
Laser treatment did not have a positive effect on the germination energy of seeds of barley variety Yakub, except for the variant with the use of rays with a wavelength of 775 nm for 30 minutes. In this variant, there was an increase in E ave by 54% compared with the control.
The use of laser treatment with a power of 100 mW, regardless of the wavelength and exposure, reduced the germination of barley seeds in laboratory conditions. Treatment with 660 nm rays for 30 minutes had the most depressing effect on seed germination.
List of sources used
1. Atroshchenko, E.E. The effect of shock-wave seed treatment on morphophysiological characteristics and plant productivity: Ph.D. dis…. cand. bio. Sciences: VAK 03.00.12. - M., 1997.
2. Veselova, T.V. Changes in the state of seeds during their storage, germination and under the influence of external factors (ionizing radiation in small doses and other weak influences), determined by the method of delayed luminescence: author. dis…. dr. bio. Sciences: 03.00.02-03. - M., 2008.
3. Danko, S.F. Intensification of the process of barley malting by the action of sound of different frequencies: dis…. cand. those. Sciences: VAK RF. - M., 2001.
4. Eskov, E.K. Influence of treatment of corn seeds with ultrafine iron powder on the development of plants and the accumulation of chemical elements in them / E.K. Eskov // Agrochemistry, No. 1, 2012. - P. 74-77.
5. Kazakova, A.S. Effect of pre-sowing treatment of spring barley seeds electromagnetic field variable frequency on their sowing qualities. / A.S. Kazakova, M.G. Fedorishchenko, P.A. Bondarenko // Technology, agrochemistry and protection of agricultural crops. Intercollegiate collection scientific papers. Zernograd, 2005. Ed. RIO FGOU VPO ACHGAA. - S. 207-210.
6. Ksenz, N.V. Analysis of electrical and magnetic effects on seeds / N.V. Ksenz, S.V. Kacheishvili // Mechanization and electrification of agriculture. - 2000. - No. 5. - S. 10-12.
7. Melnikova, A.M. Effect of laser irradiation on seed germination and seedling development / Melnikova A.M., Pastukhova N. // Ecology. Radiation safety. Socio-ecological problems. - Donbass State Technical University.
8. Neshchadim, N.N. Theoretical study of the effect of seed and crop treatment with growth substances, magnetic field, laser irradiation on yield and product quality, practical advice; experiments with wheat, barley, peanuts and roses: author. dis…. dr. Agricultural Sciences: Kuban Agronomic University. - Krasnodar, 1997.
9. Novitskaya, G.V. Changes in the composition and content of lipids in the leaves of magnetically oriented types of radish under the influence of a weak constant magnetic field / G.V. Novitskaya, T.V. Feofilaktova, T.K. Kocheshkova, I.U. Yusupova, Yu.I. Novitsky // Plant Physiology, V. 55, No. 4. - S. 541-551.
10. Novitskaya, G.V. Influence of an alternating magnetic field on the composition and content of lipids in radish seedlings / G.V. Novitskaya, O.A. Tserenova, T.K. Kocheshkova, Yu.I. Novitsky // Plant Physiology, V. 53, No. 1. - S. 83-93.
11. Novitskaya, G.V. Influence of a weak constant magnetic field on the composition and lipid content of onion leaves of different ages / G.V. Novitskaya, T.K. Kocheshkova, Yu.I. Novitsky // Plant Physiology, V. 53, No. 3. -
pp. 721-731.
12. Seed treatment - protection against diseases and guarantee of harvest // ChPUP "Biohim" URL: http://biohim-bel.com/obrabotka-semyan (Accessed: 20.03.2013).
13. Rakhmankulova, Z.F. Influence of presowing treatment of wheat seeds with salicylic acid on its endogenous content, respiratory tract activity and antioxidant balance of plants / Z.F. Rakhmankulova, V.V. Fedyaev, S.R. Rakhmatullina, S.P. Ivanov, I.G. Gilvanova, I.Yu. Usmanov // Plant Physiology, vol. 57, no. 6, pp. 835-840.
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thesis, added 10/14/2011
Features of the growth and development of soybeans. Diseases and pests. Regulators of growth and development of plants, as an element of technology that increases the resistance of plants to stress. Features of growth and development of soybean variety Vilana. Presowing treatment of seeds with regulators.
thesis, added 02/26/2009
Description of the need for zinc for the normal growth of a large number of species of higher plants. Study of the influence of Zn on the degree of germination of sunflower seeds. Measurement of chlorophyll content. Determination of the absorption capacity of the root system.
practice report, added 08/27/2015
Soybean yield in the Kaluga region. Efficiency of legume-rhizobium symbiosis. Protein content in soybeans. The yield of soybean seeds depending on the type of preparation and the method of treatment with growth regulators. Soaking seeds in fusicoccin solution.
article, added 08/02/2013
Fungi of the genus Fusarium as pathogens of more than 200 species of cultivated plants. Sources of primary infection: seeds, soil, plant debris. Features of the method of seed germination. The importance of mycorrhizal fungi in the nutrition of higher plants.
thesis, added 04/11/2012
Research of economic value and biological features of spring barley. The role of mineral nutrition for barley. Analysis of the effect of fertilizers and plant protection products on the yield, chemical composition and quality of the crop, on the development of barley diseases.
term paper, added 12/15/2013
general characteristics RRR. The effect of phytohormones on the growth of tissues and organs, the formation of seeds and fruits. The mechanism of action of phytohormones on the stress state of plants, their growth and morphogenesis. The use of phytohormones and physiologically active substances.
control work, added 11/11/2010
Characteristics of the cultivation of spring barley, its biological characteristics, especially the cultivation of soil and seeds. Consumption rates of pesticides for the treatment of barley crops from pests. The essence and purpose of harrowing, agrotechnical requirements.
term paper, added 01/04/2011
The process of post-harvest processing of grain. Active ventilation of grain and seeds. The main types of granaries in agricultural enterprises. Operational performance of the secondary cleaning machine MVU-1500. Technology of processing into pearl barley.
The goal is to study the effect of chemicals on plant growth. Objectives: to study the available literature on this issue; studying the available literature on this issue; study of the influence of certain chemicals on plants (for example, onions). study of the influence of certain chemicals on plants (for example, onions).
Experiment Method 
To study the effect of chemicals, 4 samples were made: 1 - nickel sulfate 1 - nickel sulfate 2 - iron sulfate 2 - iron sulfate 3 - control sample (without adding chemicals) 3 - control sample (without adding chemicals) 4 - potassium permanganate 4 - potassium permanganate
Conclusions Excess ferrous sulphate stains the cells in a dark color and slows down the growth of the root system. Excess iron sulfate stains the cells dark and slows down the growth of the root system. Potassium permanganate has the same effect. Potassium permanganate has the same effect. An excess of nickel sulphate destroys the cells of the plant and stops its growth. An excess of nickel sulphate destroys the cells of the plant and stops its growth.
References 1. Bezel V.S., Zhuikova T.V. Chemical pollution of the environment: removal of chemical elements by aboveground phytomass of herbaceous vegetation // Ecology. - - 4. - S Dobrolyubsky O.K. Microelements and life. – M., Ilkun G.M. Air pollutants and plants. - Kyiv: Naukova Dumka, - 248 p. 4. Kulagin Yu.Z. Woody plants and the industrial environment. – M.: Nauka, – 126 p. 5. Solyarnikova Z.N. Tree and shrub plants in the conditions of tire production // Introduction and experimental ecology of plants: Sat. articles. - Dnepropetrovsk: Science, - Shkolnik M.Ya., Makarova N.A. Microelements in agriculture. - M., 1957.
Influence of chemicals on the growth and development of plants. Completed by: Victoria Ignatieva, 6th grade student Supervisor: Yu.K. Putina, teacher of biology and chemistry Municipal public educational institution Nizhnesanarskaya secondary school of the Troitsky municipal district of the Chelyabinsk region 2017
Purpose: to study the effect of chemicals on the growth and development of plants. Objectives: To study the available literature on this issue; To get acquainted with the available methods for studying the effect of chemicals on the growth and development of plants. Make a conclusion about the effects of chemicals based on your own research. Develop recommendations for improving conditions for growing cultivated plants. Hypothesis: We assume that chemicals will negatively affect the growth and development of plants.
Object of study: Bulb onion, Common bean Subject of study: the effect of chemicals on plants.
Chemical Sampling Technique
To study the effect of chemicals, 6 samples were taken: No. 1 - copper sulfate CuSO4 * 5H2O No. 2 - zinc sulfate ZnSO4 * 7H2O No. 3 - iron sulfate FeSO4 * 7H2O No. 4 - potassium permanganate KMnO4 No. 5 - lead sulfate PbSO4 No. 6 - control sample (no added chemicals)
The results of the study of control samples Control sample No. 6 (onion bulb) development proceeds intensively with the formation of many adventitious roots) Control sample No. 6 (Bean plant) - growth and development are within the normal range
The results of the study of test samples when exposed to copper sulfate Sample No. 1 The appearance is not a large number roots, their growth soon stops, they darken. Sample No. 1After adding a copper sulfate solution, the leaves curled immediately, the plant died by the end of the 1st week of the experiment
The results of the study of test samples under the influence of zinc sulfate Sample No. 2 The appearance of a large number of roots, their growth is insignificant. Sample No. 2 In the plant, after adding a solution of zinc sulfate, the leaves usually developed during the first week of experiments, then with an increase in the concentration of the solution, the leaves turned yellow, curled up
The results of the study of test samples under the influence of iron sulfate Sample No. 3 The appearance of a small number of roots, their growth soon stops, they darken. Sample No. 3. the plant developed three leaves, but then they began to curl and turn yellow
The results of the study of test samples when exposed to potassium permanganate Sample No. 4 The bulb with the addition of potassium permanganate solution (No. 4) developed poorly, roots 1-2 mm, then growth stopped Sample No. 4 The plant lost 3 leaves on day 4, then the rest withered
The results of the study of test samples under the influence of lead sulphate Sample No. 5 The bulb had a sufficient number of roots, but small in size. The bean plant had large leaves, but of a pale color, which also curled slightly at the end of 2 weeks
The control sample (No. 6) had even light cells without signs of any deformation.
Onion cells from the experimental sample with the addition of iron sulfate (No. 3) had an even structure, but their cytoplasm was darkly colored.
Onion cells from an experimental sample with the addition of potassium permanganate (No. 4) turned blue. The cells had an even structure.
Conclusions: An excess of iron sulfate stains the cells in a dark color and slows down the growth of the root system. Potassium permanganate has the same effect. Excess copper sulphate destroys plant cells and stops its growth.
GOU Gymnasium 1505
"Moscow City Pedagogical Gymnasium-Laboratory"
"Influence various substances on the growth and development of plants"
Supervisor:
Moscow, 2011
Introduction……………………………………………………………………………3
Theoretical part
1.1 Plant growth and development factors…………………………………………………….5
1.2 The influence of heavy metals on the growth and development of plants…………………………6
2. Experimental part
2.1. Research results. Dry residue analysis……………………………….14
3. Conclusion……………………………………………………………………………….19
References………………………………………………………………………….21
Introduction
The relevance of research. Megacities are large centers of intensive environmental pollution with heavy metals: Moscow is one of them. In such a densely populated city, it is necessary to take into account the impact of heavy metal salts on human health, both in homes and in workplaces and schools. The relevance of my research follows from the fact that homes and workplaces are almost always poorly ventilated, and sources of heavy metals are usually ignored. Especially, plants that are in every house or apartment are exposed to the harmful effects of salts of heavy metals. Plants easily accumulate various substances and are not capable of active movement. Therefore, according to their condition, one can judge about environmental situation. And since plants are bioindicators, i.e. many changes have specific manifestations, they are ideal for research work. Thus, in this work it is necessary to find out exactly how salts of heavy metals affect the growth and development of plants.
aim research is the accumulation and processing of data on the effect of salts of heavy metals on the growth and development of plants, as well as the comparison of information from the literature used with the results of a scientific experiment that I am going to conduct and then describe in my work. Before starting the experimental activity, I set up several important tasks:
Plant Development Table
1 Plants of groups 3 and 4 were watered with solutions exceeding MPC (Maximum Permissible Concentration)
CuSO4 - 0.05g/10l - exceeded 10 times
Pb(NO,02mg/10l - exceeded 200 times
plant group | Date of observation | Observation (plant growth) |
|
(Control) | ||
1pc broke 2.9cm-5.7cm |
||
2pcs broke 3.4cm-6.3cm |
||
1 piece broke, stopped absorbing water. Plant Size: 3.8cm-6.8cm |
||
1pc broke, a real leaf began to grow, the stems of the plant grew strongly, stopped watering the plants 3.9cm-6.8cm, a real leaf began to erupt |
||
4.1cm-7.2cm, watering has not started, the plants still do not absorb water. |
||
4.3cm -7.5cm |
||
4.5cm–7.7cm the last day of observations, due to the death of most plants |
||
The smallest of all plant groups. Plant size: 1.5cm–2.5cm |
||
1pc broke 2.5cm-4.9cm |
||
1 piece died, the plants became frail, they look worse than other groups of plants. Plant size: 3.6cm-6.2cm |
||
2 pieces broke, stopped watering, as they stopped absorbing water. Plant size 3.8cm-6.7cm |
||
4.1cm-7cm, real leaf appeared |
||
They practically did not change in growth, the real leaf became even larger, did not start watering, since they still do not absorb water |
||
4.2cm-7.3cm, the largest number of surviving plants |
||
4.6cm-7.4cm, the last day of observations, due to the death of most plants |
||
III group | ||
1pc perished 1.5cm-3.2cm |
||
1pc broke 2.7cm-6cm |
||
plants look frail, 1pc wilted, become dark green in color, much darker than other groups of plants. Plant Size: 3.2cm-6.7cm |
||
1 piece withered, 5 pieces fell, 1 piece broke, they began to absorb water poorly. Plant Size: 3.3cm-6.9cm |
||
A new real leaf began to cut through, the plants completely stopped absorbing water, in connection with this, they stopped watering 7 pieces grow, the rest fell and broke. Plant size 3.4cm-7.3cm |
||
Almost all plants have fallen, look sluggish and lifeless compared to other groups of plants 2pcs have fallen |
||
3.7cm-7.8cm cost only 5pcs, all others fell off, look lifeless |
||
3.8cm-8cm the last day of observations, due to the death of most plants |
||
IV group | ||
1.6cm-2.3cm 1pc wilted |
||
Several plants have fallen start to wrap leaves 2.7cm-5.8cm |
||
1 piece fell and broke, all the plants leaned to one side, the leaves wrapped even more tightly. Plant size: 3.1cm–6.2cm |
||
2 pieces fell and broke, a real leaf began to grow, stopped watering, because the plants stopped absorbing water. Plant size: 3.4cm–6.7cm, |
||
2 pieces fell off, the real leaf is clearly visible, some plants look quite frail. Plant size 3.6cm–7cm |
||
1 piece broke, almost all plants look frail and lifeless, practically did not change in growth, the largest true leaf of all plant groups |
||
Look sick, 1pc wilted. Plant size: 4.5-7.9 |
||
4.6cm-8cm the last day of observations, due to the death of most plants |
From the data given in the table, it follows that, compared with the control group, plants watered with a solution of lead nitrate grew more intensively, the growth of watercress watered with melt water and a solution of copper sulfate was slowed down.
The condition of the plants of different groups differed: after 6 days of observation, the plants of the 2nd and 3rd groups began to break, in the plants of the 4th group, the leaves began to wrap. In plants watered with melt water, growth retardation was observed earlier than others (after 8 days), watercress with lead was ahead of the control group plants in growth.
2.2. Dry residue analysis for lead and copper ions.
After finishing the watercress growth rate study, I analyzed the dry residue for the presence of lead and copper ions in each sample. For this, the plants were dried, each group of plants burned separately, and analyzed for the presence of ions. The following are examples of qualitative reactions to lead ions and copper ions:
1. Qualitative reaction for lead ions: lead ions in solution are determined using iodide ion I -
Potassium iodide solution was taken as a source of iodide ions.
2. Qualitative reaction to copper ions: copper ions in solution are determined with the power of sulfide ions S2-
Sodium sulfide solution was taken as a source of sulfide ions.
Analysis results:
None of the studied ions was determined in the control group of plants. In the group of plants watered with melted snow, lead ions and copper ions in a very small amount were determined. In the dry residue of plants watered with a solution containing copper, only traces of copper were found. In the group of plants watered with a solution of lead nitrate, lead ions were determined only the next day.
As a result of the work carried out, I came to the following conclusions:
1. Lead stimulates watercress growth, causing leaf curl and premature plant death.
2. Copper accumulates in plants and causes slight stunting of watercress growth and brittle stems.
3. Analysis of plants watered with melt water showed that in the snow collected along the road to the street. The playing room contains both lead ions and copper ions, which have a detrimental effect on the growth and development of plants.
3. Conclusion
The conducted study of literary sources and experimental research made it possible to compare the obtained data.
3.1. Literary information
Information from the literature indicates that with an excess of lead, there is a decrease in yield, suppression of photosynthesis processes, the appearance of dark green leaves, twisting of old leaves and leaf fall. In general, the effect of lead excess on plant growth and development has not been sufficiently studied.
Copper causes toxic poisoning and premature death of plants.
3.2 Experimental data
Our study on the cultivation of watercress plants under conditions of intake of various heavy metal ions (lead and copper), as well as the effect of melted snow on the growth and development of lettuce, showed that lead causes increased plant growth when leaves are twisted; copper slows down the growth rate and increases the brittleness of the stems. Melted snow causes early stunting and increased fragility of plants.
3.3 Conclusions
Comparing the data from the literature sources and the obtained experimental data, we came to the conclusion that the literature sources are confirmed by the study. However, there are peculiarities: we did not conduct a study of the effect of lead on plant yields, it is interesting that lead in the group of plants watered with a solution of lead nitrate was determined only the next day. An additional study of the literature data showed that lead accumulates primarily in the roots of plants. To analyze the dry residue for lead and copper ions, we took only the aerial part of the shoot. Increasing the concentration of copper ions in the solution by 200 times from the MPC did not give the expected results - instead of the expected early death of watercress, growth lag was observed. The presence of lead and copper ions in melted snow did not cause a net effect (increased plant growth and brittle stems), but slowed down the rate of growth and development of plants with an increase in brittleness.
Applications
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Development of watercress plants
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Stem brittleness in individual watercress groups
Bibliography.
Dobrolyubsky and life, - M .: Mol. Guards, 1956. Drobkov and natural radioactive elements in the life of plants and animals, - Popular science series., M .: AN SSSR, 1958. Harmful chemicals. Inorganic compounds of groups I-IV, Ed. prof. Filov. V. A. - M.: Chemistry, 1988. Shapiro Y. S. Biological Chemistry, M. - Ventana-Graf Publishing Center, 2010. General Chemistry, Ed. , - M .: Higher school, 2005. Podgorny, - M .: Publishing house of agricultural literature, magazines and posters, 1963. , Kovekovdova in soils and plants of Ussuriysk and the Ussuriysk region, - El. journal Researched in Russia, 2003. zhurnal. ape. *****/articles/2003/182.pdf Medical reference book. www. *****
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A plant organism is made up of many cells. Cells are the basic biological units in the structure of the plant body. In all cells, the most important life processes take place, and above all the process of metabolism. Different cells are adapted to different types of life. However, a plant is not a simple collection of cells. All cells, tissues and organs are closely interconnected and form a single whole. Different cells are specialized in different directions, they cannot live without other cells. For example, root cells could not live without green leaf pulp cells. An important role in the life of plants is played by mineral nutrition, carried out by the root of the plant. Deficiency or excess of any chemical element in plant nutrition negatively affects its growth and development. aim my job was to study the effect of chemicals on plant growth.
To achieve this goal, the following tasks :
studying the literature on this issue;
study of the influence of certain chemicals on plants (for example, onions).
Thus, object research was the onion plant. This plant was chosen because in the 5th grade, while studying the topic "Structure of the cell", I learned how to prepare a micropreparation of onion peel. Using micropreparations, it is possible to study the effect of chemicals not only on plant growth, but also on the development of plant cells. Subject research was the effect of chemicals on plant growth.
Was formulated hypothesis studies - some chemicals can negatively affect the growth and development of plants
Chapter I. Literature Review
The role of plants in nature and human life
Imagine that there is not a single plant left in the world. What will happen then? The fact that it will not be beautiful is not so bad. But the fact that we cannot live without plants is really very bad. After all, plants have one very important secret!
Amazing transformations take place in the leaves of plants. Water, sunlight and carbon dioxide - the one that we exhale, turn into oxygen and organic substances. Oxygen is necessary for us and all living beings for breathing, and organic matter for nutrition. So, we can say that in plants there is a real chemical laboratory for the production of vital substances. In addition, the oxygen released by plants maintains the ozone layer of the atmosphere. It protects all life on Earth from the harmful effects of short-wave ultraviolet rays.
Plants play an important role in our lives, participating in ecological food chains, being producers of atmospheric oxygen, and performing environmental protection functions. Therefore, it is especially important to know how plants react to different chemicals.
The influence of various chemicals on living organisms
Chemicals are made up of elements. Mineral elements play an important role in the metabolism of plants, as well as the chemical properties of the cytoplasm of the cell. Normal development, growth cannot be without mineral elements. All nutrients are divided into macro- and microelements. Macroelements include those that are found in plants in significant quantities - carbon, oxygen, hydrogen, nitrogen,
phosphorus, potassium, sulfur, magnesium and iron. Trace elements include those that are found in plants in very small quantities, these are boron, copper, zinc, molybdenum, manganese, cobalt, etc.
All plants cannot develop normally without these elements, since they are part of the most important enzymes, vitamins, hormones and other physiologically active compounds that play an important role in plant life. Macronutrients regulate the growth of the vegetative mass and determine the size and quality of the crop, activate the growth of the root system, enhance the formation of sugars and their movement through plant tissues; trace elements are involved in the synthesis of proteins, carbohydrates, fats, vitamins. Under their influence, the content of chlorophyll in the leaves increases, and the process of photosynthesis improves. Microelements play an extremely important role in the processes of fertilization. They have a positive effect on the development of seeds and their sowing qualities. Under their influence, plants become more resistant to adverse conditions, drought, disease, pests, etc.
Some elements, such as boron, copper, zinc, are needed in small quantities; in higher concentrations, they are very toxic. Excessive content in the soil has a toxic effect on the plant. manganese . The harmful effect of this element is enhanced on acidic (sandy, sandy, peaty), as well as compacted or excessively moistened soils containing little mobile compounds of phosphorus and calcium. The lack of these elements enhances the flow of manganese into the plant and its harmful effects on tissues. On potatoes, this manifests itself in the form of brown spots on the stems and petioles of the leaves, the stems and petioles become watery, brittle. The tops dry out prematurely. Parallel to harmful influence manganese on the plant can
there are also signs of starvation from a lack of molybdenum and magnesium, the flow of which into the plant, in this case, sharply weakens.
Failed to install role for a long time iodine in plant metabolism. It is known that vegetables and mushrooms are richer in them than fruits. Moreover, there is more iodine in the aerial parts of plants than in the roots. Terrestrial plants contain several times less iodine than marine plants, in which it reaches 8800 mg/kg dry weight. For comparison, cabbage, for example, can accumulate iodine from 0.07 to 10 mg per kg of dry matter. What is the role of iodine in plant life? It turned out that in low concentrations, iodine stimulates plant growth and improves crop quality. This happens due to the fact that iodine affects nitrogen metabolism, in particular, the ratio of protein and non-protein nitrogen and regulates the activity of certain enzymes. Using stimulating properties, seeds are treated with a solution of potassium iodide (0.02%) before sowing. Content sodium in the body of plants is an average of 0.02% (by weight). Sodium is important for the transport of substances across membranes, is included in the so-called sodium-potassium pump (Na + /K +). Sodium regulates the transport of carbohydrates in the plant. A good supply of sodium to plants increases their winter hardiness. With its deficiency, the formation of chlorophyll slows down. Sodium is part of table salt, which negatively affects the life of the plant cell. Plasmolysis of the cell is observed under the action of sodium chloride solution (appendix). Plasmolysis is the separation of the parietal layer of the cytoplasm from the cell membrane of the plant cell. Solutions of salts or sugars of high concentration do not penetrate into the cytoplasm, but draw water from it. Plasmolysis is usually reversible. If the cell is moved from a saline solution to water, then it will again be vigorously absorbed by the cell and the cytoplasm will return to its original position.
Chapter II. Experiment Method
The research was carried out in 2015. For work, I needed onion to germinate it, and then feed it with chemicals. To determine the effect of chemicals, the most accessible substances that are found at home were selected: table salt, potassium permanganate (potassium permanganate), iodine.
To study the effect of chemicals, 5 samples were made, which were fed with different chemicals 2 times a week (Fig. 1):
No. 1 - control sample ( tap water, no added chemicals)
No. 2 - holy water
No. 3 - potassium permanganate solution
No. 4 - salt solution
No. 5 - iodine solution
After observing the development of the root system, the prototypes were dissected, the resulting sections were examined under a digital microscope, and photographs were taken.
Chapter III. Results of own research and their analysis
In the course of the study, I found that in samples with the addition of potassium permanganate and table salt, the root system developed poorly for three weeks. The most powerful root system was in the control sample No. 1 without the addition of chemicals (Fig. 2). You should pay attention to sample No. 5 iodine solution. In the onion plant, not only the roots, but also the leaves are well expressed. During the experiment, I observed intensive leaf development from the second week.
Examining onion cells under a microscope, the following results were obtained:
The control sample No. 1 had even light cells without signs of any deformation (Fig. 3)
Sample No. 2, holy water, had even cells without signs of any deformation, but compared to the cells of the control sample, the cell size was smaller (Fig. 4)
Onion cells from a prototype with the addition of potassium permanganate No. 3 acquired a shade of blue color. The cells had an even structure (Fig. 5)
In sample No. 4 with the addition of table salt, plasmolysis is observed - the parietal layer of the cytoplasm is separated from the cell wall of the plant cell (Fig. 6)
Sample No. 5 with the addition of iodine had even light cells without signs of deformation, similar to the cells of the control sample (Fig. 7)
Conclusion
As a result of the work, it was found that some chemicals can accumulate in plant cells and negatively affect their growth and development, thus, the hypothesis was confirmed. Excess potassium permanganate stains cells more dark color and slows down the growth of the root system. Excess salt destroys the cells of the plant and stops its growth.
According to the studied literature sources, I experimentally confirmed the stimulating effect of iodine on plant growth.
Bibliography
Artamonov V.I. Entertaining plant physiology - M.: Agropromizdat, 1991.
Dobrolyubsky O.K. Microelements and life. - M., 1996.
Ilkun G.M. Air pollutants and plants. - Kyiv: Naukova Dumka, 1998.
Orlova A.N. From nitrogen to harvest. - M.: Enlightenment, 1997
Shkolnik M.Ya., Makarova N.A. Microelements in agriculture. - M., 1957.
Internet resources:
dachnik-odessa.ucoz.ru
biofile.ru
Application
Plant cell plasmolysis
