Schemes of experiments on the effect of toxic substances on plants. Start in science. Influence of humates on the general development of plants, seeds and root system
City scientific - practical conference of schoolchildren "Science Day"
Research project on the topic:
"Influence of chemicals
on the growth and development of plants"
The work was completed by: a student of grade 9b
MBOU "Gymnasium No. 2"
Bashkireva Maria
Leaders:
biology teacher
Charaeva Svetlana Aleksandrovna, chemistry teacher
Rusakova Elena Vitalievna
Kurchatov
Introduction……………………………………………………………………3
Chapter I. Theoretical part……………………………………………6
6
1.2 Plants in conditions of environmental pollution……………6
1.3 The influence of various chemicals on living organisms ... 8
Chapter II. Experimental part…………..…………………………11
2.1. Description of the experiment……………………………………………...12
2.2. Research results………………………………………….. 13
2.3. Microscopic examination……………………………….. 14
Conclusion……………………………………………………………….15
References……………………………………………………………16
Internet resources………………………………………………………..17
Introduction
Rationale for the choice of the project topic and its relevance
The importance of green plants in nature is great, they heal the air, enrich it with oxygen necessary for the respiration of all living beings, and purify it from carbon dioxide. In order for plants to grow and develop normally, favorable environmental conditions are needed. The necessary conditions are heat, air, water, food, light. Due to environmental pollution, harmful compounds penetrate the soil and are absorbed from it by the roots, which negatively affects the condition and growth of flora representatives. Consider the influence of some factors on plant growth under the influence of chemicals.
One of the most dangerous types of chemical pollution of the natural environment is heavy metal pollution, which includes iron, zinc, nickel, lead, copper and chromium. Many heavy metals, such as iron, copper, zinc, molybdenum, are involved in biological processes and, in certain quantities, are trace elements necessary for the functioning of plants, animals, and humans. On the other hand, heavy metals and their compounds can have a harmful effect on the human body, they can accumulate in tissues, causing a number of diseases. Metals with no useful role in biological processes, such as lead and mercury, are defined as toxic metals.
Among the various pollutants, heavy metals (including mercury, lead, cadmium, zinc) and their compounds are distinguished by their prevalence, high toxicity, many of them also have the ability to accumulate in living organisms. They are widely used in various industrial productions, therefore, despite the purification measures, the content of heavy metal compounds in industrial wastewater is quite high. They also enter the environment with domestic sewage, with smoke and dust from industrial enterprises. Many metals form stable organic compounds; the good solubility of these complexes facilitates the migration of heavy metals in natural waters.
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 under the influence of copper sulfate Sample No. 1 The appearance of a small number of 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.
slide 1
Effect of bean seed treatment with chemical solutions on plant growth and developmentslide 2
The purpose of the study: to find out the stimulating effect of seed treatment with various chemicals on the development of bean plants. Hypothesis: Seed treatment has a stimulating effect on plant development
slide 3
Research objectives: to give a scientific description of the stimulating effect of various chemicals on the development of plants; master the methodology of the experiment to identify the stimulating effect of various chemicals on the development of plants; using the proposed method to investigate the stimulating effect of six chemicals on the development of bean plants; draw conclusions based on the results obtained about the stimulating effect of chemicals on the growth and development of plants.
slide 4
Relevance of the study: Modern crop production cannot do without special techniques that increase the yield of plants, improve their growth and development, and protect against diseases and pests. Currently, pre-sowing seed treatment is used in practice. However, there is no complete information about which chemicals and how they affect the seeds of certain plants, how the seed treatment affects the various phases of the plant. In this regard, the topic of our study is relevant.
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PRACTICAL STUDY 1 sample - 1% solution of food salt 2 sample - % glucose solution 3 sample -1% solution of drinking soda 4 sample -1% solution of boric acid 5 sample -1% solution of potassium permanganate 6 sample - water.
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Slide 7
Slide 8
Slide 9
The results of the study showed many chemicals are plant growth regulators; some chemicals have an inhibitory effect. In this case, it is a solution of boric acid; the stimulating effect of chemicals is manifested at different stages of development of bean plants; edible salt affects the rate of fruit ripening; drinking soda affects the rate of emergence of the germinal root, the dynamics of seedlings; potassium permanganate affects the height of plants; glucose affects yield.
Mineral elements play an important role in the metabolism of plants, as well as the colloid-chemical properties of the cytoplasm. Normal development, growth and physiological processes cannot be without mineral elements. They can play the role of structural components of plant tissues, catalysts for various reactions, regulators of osmotic pressure, components of buffer systems, and regulators of membrane permeability.
Some elements, including iron, copper and zinc, are required in very small amounts, but they are necessary because they are part of the prosthetic groups or coenzymes of certain enzyme systems.
Other elements such as manganese and magnesium function as activators or inhibitors of enzyme systems.
Some elements, such as boron, copper and zinc, which are necessary for the functioning of enzymes in small quantities, are very toxic in higher concentrations. Copper is part of the oxidative enzymes polyphenol oxidase and ascorbine oxidase. Iron - is part of the cytochromes and the enzymes catalase and peroxidase. Manganese - stimulates plant respiration, redox processes, photosynthesis, formation and movement of sugars. Its main function is to activate enzyme systems. In addition, it affects the availability of iron. The average content of manganese in plants is 0.001%.
Excess or lack of macro or microelements adversely affects plants. A high concentration of elements causes coagulation of plasma colloids and its death.
Currently, environmental pollution, including heavy metals, is increasing every year, which has a negative impact on soils and plants and poses a threat to human health.
Excessive intake of heavy metals in organisms disrupts metabolic processes, inhibits growth and development, and leads to a decrease in the productivity of crops.
The greatest danger is represented by those metals that, under normal conditions, are necessary for plants as trace elements. These primarily include zinc, copper, manganese, cobalt and others. Accumulating in plants cause negative effects. With an excess of copper in plants, chlorosis and necrosis of young leaves occurs, the veins remain green, iron stops the growth of the root system and the entire plant. The leaves take on a darker shade. If, for some reason, the excess of iron turned out to be very strong, then the leaves begin to die and crumble without any visible changes. Petroleum products disrupt membrane permeability, block the action of a number of enzymes, negatively affect plants, reduce yield and fruit ripening time.
GOU Gymnasium 1505
"Moscow City Pedagogical Gymnasium-Laboratory"
"The influence of 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 the ecological 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 |
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2pcs broke 3.4cm-6.3cm |
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1 piece broke, stopped absorbing water. Plant Size: 3.8cm-6.8cm |
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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 |
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4.1cm-7.2cm, watering has not started, the plants still do not absorb water. |
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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 |
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4.2cm-7.3cm, the largest number of surviving plants |
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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 |
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plants look frail, 1pc wilted, become dark green in color, much darker than other groups of plants. Plant Size: 3.2cm-6.7cm |
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1 piece withered, 5 pieces fell, 1 piece broke, they began to absorb water poorly. Plant Size: 3.3cm-6.9cm |
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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 |
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Almost all plants have fallen, look sluggish and lifeless compared to other groups of plants 2pcs have fallen |
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3.7cm-7.8cm cost only 5pcs, all others fell off, look lifeless |
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3.8cm-8cm the last day of observations, due to the death of most plants |
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IV group | ||
1.6cm-2.3cm 1pc wilted |
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Several plants have fallen start to wrap leaves 2.7cm-5.8cm |
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1 piece fell and broke, all the plants leaned to one side, the leaves wrapped even more tightly. Plant size: 3.1cm–6.2cm |
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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, |
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2 pieces fell off, the real leaf is clearly visible, some plants look quite frail. Plant size 3.6cm–7cm |
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1 piece broke, almost all plants look frail and lifeless, practically did not change in growth, the largest true leaf of all plant groups |
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Look sick, 1pc wilted. Plant size: 4.5-7.9 |
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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. *****
