RU2759172C1 - Method for obtaining a complex sorption-stimulating preparation to reduce the allelotoxicity of soils - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: the method for preparing a complex sorption-stimulating drug to reduce the allelotoxicity of the soil is characterized by the fact that aqueous solutions of bentonite, potassium or sodium humate, brewer’s yeast autolysate (BYA) and polyethylene glycol (PEG) are mixed in a mass ratio 4:0.9-1.1:2.8-3.2:0.35-0.45, accordingly, with continuous stirring for 5-6 hours, a suspension is obtained, which is dried until a dry residue is obtained, followed by its grinding into a powder.

EFFECT: invention makes it possible to increase the effectiveness of a drug that reduces the allelotoxicity of soils by sorption of allele toxins, which leads to a decrease in their negative impact on plant development, and at the same time creates optimal conditions for the vital activity of microorganisms that accelerate plant development.

4 cl, 1 tbl

Description

Technology area

The invention relates to agriculture and can be used in greenhouse farms if it is necessary to stimulate the development of berries, flowers, vegetables, seedlings, as well as for rooting seedlings of ornamental crops. The inventive method is aimed at obtaining a drug that helps accelerate the development of plants, increase their resistance to phytopathogens and pests and, as a result, increase yields by reducing the negative effect on seeds and plants of allelotoxicity (soil fatigue) of soils and soils.

State of the art

The phenomenon of soil fatigue, which consists in the negative effect of soils on the development of plants, according to many researchers, is primarily due to the accumulation of allelotoxins in the soil due to its (soil) high sorption capacity.

Studies to reduce the allelotoxicity of soils describe their washing with a large amount of water [1] or organic solvents [7], freezing, autoclaving and liming [1].

In addition, there are known methods of warming up the soil and adding manure to them to reduce allelotoxicity [8]. At the same time, the amount of manure that must be applied to the soil to achieve the desired result is large, and its availability due to the sharp reduction in the number of cattle in Russia is small, therefore this method does not give the expected effect.

During autoclaving, soil samples are kept at a temperature of 100-120 ° C at an increased pressure of water vapor for 30 minutes, after which the decrease in allelotoxicity of soils is checked based on the use of a test culture of a microorganism ( Azotobacter sp. ) [1]. The disadvantages of this method include the complexity of its implementation in agricultural practice, as well as the irreproducibility of the results obtained.

Washing of soil samples, as a rule, is carried out with 2% sulfuric acid or a solution of 2% potassium hydroxide, followed by saturation of the soil with calcium. As a result of the application of this method, a decrease in the allelotoxicity of soils and the restoration of soil fertility are indeed observed [1], however, the main disadvantage of this method is its narrow field of application, which is limited by laboratory conditions and is not projected onto an industrial scale.

Separate studies are devoted to the fact that allelotoxicity of soils can be reduced by microorganisms that use allelotoxins as carbon sources for their nutrition [1, 9-11]. It was shown [11] that the decrease in the allelotoxicity of soils occurs more slowly on sterile soils in comparison with non-sterile samples. The disadvantages of this method are the difficulty in identifying microorganisms that consume allelotoxins as a carbon source, as well as the complexity of their cultivation for use on an industrial scale.

As means and methods of reducing the allelotoxicity of the soil, it is also known to use the drug biochar [12], which is introduced into soils and, along with a decrease in allelotoxicity, increases their fertility by increasing the sorption capacity of soils in relation to nutrients and improves the availability of these substances for plants [2 ]. The disadvantages of the known drug include its high consumption, as well as the large dependence of the positive effect on the quality of the feedstock and production conditions.

A known method for reducing allelotoxicity of soils, which consists in the use of crop rotations or fruit changes [3], which reduce the flow of allelotoxins into the soil. However, this approach is applicable only to the cultivation of field crops. The possibility of its use in horticulture, vegetable growing, floriculture, protected ground is doubtful. The use of crop rotations also does not allow to actively influence the state of soils, ensuring their recovery (reduction of allelotoxicity) at a rapid pace, which is often required by various branches of agriculture. In addition, a significant disadvantage of this method is the need to alternate sown crops.

It is also known from the prior art to use bentonites and humates as agents for treating seeds and feeding plants (RF patent No. 2722727, 2724511), while, as a rule, a humus preparation (humate) is activated by introducing bentonite into it with subsequent action on the mixture, for example, ultrasound. The known method makes it possible to obtain a modified humus preparation enriched with bentonite and having empirically confirmed data on the degree of influence on the stimulation of plant growth. However, there is no information in the prior art on the effectiveness of bentonite-humate mixtures for reducing the allelotoxicity of the soil when it is treated with such preparations.

From the prior art (RF patent No. 2728697), a preparation is known containing bentonite, sodium or potassium humate, autolysate of brewer's yeast (APD) and polyethylene glycol (PEG) in certain proportions, however, this preparation is intended for treating seeds in a semi-dry way and does not give the expected effect when introducing it into the soil.

The closest to the claimed technical solution is the use of activated carbon, which reduces allelotoxicity [4].

The main disadvantage of this technique is its low efficiency, as a result of which, to achieve the optimal effect, a significant amount of sorbent is required, which significantly limits the cost-effective areas of application.

The technical problem solved by the claimed invention consists in the need to overcome the disadvantages inherent in analogs and the prototype, by reducing consumption while increasing the effectiveness of the drug that reduces allelotoxicity of soils through sorption of allelotoxins, which leads to a decrease in their negative impact on plant development, and thus creating optimal conditions for the vital activity of microorganisms that accelerate the development of plants.

Brief disclosure of the essence of the invention

The technical result achieved with the use of the claimed invention consists in providing the possibility of reducing the allelotoxicity of soils and, as a consequence, reducing the supply of allelotoxins to plants, as well as creating favorable conditions for the functioning of microorganisms that stimulate the development of plants when using a sorption-stimulating drug obtained by the claimed method. The use of such a preparation helps to increase the resistance of plants to phytopathogens and pests, as well as to accelerate the germination of seeds and the development of plants from them.

The claimed technical result is achieved by the fact that in the method of obtaining a complex sorption-stimulating drug to reduce the allelotoxicity of the soil, according to the technical solution, aqueous solutions of bentonite, potassium or sodium humate, brewer's yeast autolysate (APD) and polyethylene glycol (PEG) are mixed in a mass ratio of 4: 0 , 9-1.1: 2.8-3.2: 0.35-0.45, respectively, with continuous stirring for 5-6 hours to obtain a suspension, which is dried until a dry residue is obtained, followed by grinding it into powder ... Suspension of bentonite, humate, APD and PEG has a concentration of 50-100 g / l. In the course of preparation, the resulting suspension is dried by keeping at a temperature of 70-80 ^° C until traces of visible moisture are removed. Grinding of the dry residue can be carried out, for example, with an impact mill to obtain particles of 5-200 microns in size.

Concentration ranges were selected in which the resulting drug acts most effectively. It was revealed that at certain ratios "calcium bentonite - humate - APD - PEG" a bentonite-humate complex appears, which has a significant sorption capacity in relation to organic substances (allelotoxins).

To ensure a balanced amount of bentonite-humate complex in the preparation empirically determined and checked the boundaries of the range of its concentration. The value of the lower boundaries of the intervals of calcium bentonite and humate is due to the ability of the bentonite-humate complex to effectively absorb and fix allelotoxins entering the seeds from the soil, and the upper limit is due to the fact that the amount of biologically active substances from soils that can stimulate the development of seeds is fixed on the sorbent in the minimum degree.

For APD, the selected lower limit of the concentration range is associated with the need for additional blocking of the active centers of the sorbent capable of fixing stimulating biologically active substances from soils, and the upper limit is due to the displacement of allelotoxins from soils by stimulating biologically active substances and an increase in their amount entering the seeds, which leads to an increase in inhibiting seed development. At the same time, it should be borne in mind that this process is superimposed on the intake of substances from the APD into the seeds that stimulate the development of seeds (for example, vitamins).

The introduction of PEG into the preparation enhances the disintegration of aggregates of montmorillonite particles, which are part of bentonite, to individual particles and an increase in the sorption surface area of the preparation. For PEG, which is a surfactant, the selected range of values is due to the presence of optimal concentrations in seeds (plants), at which biochemical reactions take place at maximum speed, taking into account the fact that part of the PEG is fixed on the bentonite-humate complex during the preparation of the claimed preparation.

Implementation of the invention

The inventive method provides for the preparation of a complex sorption-stimulating preparation intended not for seed treatment, but for introduction into the soil. At the same time, calcium bentonite, APD and PEG are added to humic substances in selected proportions. When humic substances interact with bentonite, clay-humus complexes are formed, which have a much higher sorption capacity (compared to individual components) in relation to organic substances [5], and when introduced into the soil, allelotoxins are fixed, preventing them from entering plants and inhibiting their development. It should be noted that a simple addition of solutions of the above components does not give the expected effect, but only provides a preparation in which each active component acts in accordance with its inherent physicochemical properties without additional synergistic effect. The introduction of PEG into the preparation enhances the disintegration of aggregates of montmorillonite particles included in the bentonite composition to individual particles and an increase in the sorption surface area of the bentonite-humate mixture. The addition of autolysate of brewer's yeast to the obtained sorption complex improves the conditions for the functioning of microorganisms that stimulate the development of plants.

Further description of the essence of the invention is made using examples of specific implementation.

The experiments were carried out on the seeds of a test culture - spring wheat variety "Liza" on sod-podzolic soil from the vicinity of the Yakhroma river floodplain with a moisture content of 18.1%.

For the preparation of the sorption-stimulating preparation, we used a liquid concentrate of potassium (sodium) humate produced by OOO NVC Agrotechnology from brown coal and calcium bentonite according to OST 18-49-71 (http://novagrohim.ru/index.php/partners/agriculture / 27-agriculture / 85-humates), autolysate of brewer's yeast (APD) produced by Biotech plus LLC and polyethylene glycol (PEG) from Merck with a molecular weight of 400. These preparations have proven themselves well as agents for seed treatment and plant nutrition , however, there is no information on their effectiveness in the composition of bentonite-humate mixtures and their derivatives in soil cultivation in the prior art.

In general, aqueous solutions of bentonite (with a concentration of 30 to 60 g / l, preferably 35 to 45 g / l, preferably 40 g / l), humate (with a concentration of 5 to 40 g / l, preferably 10 g / l), and APD (concentration from 8 to 15 g / l, preferably 12 g / l).

The preparation procedure consisted in obtaining a suspension of bentonite, humate, APD and PEG with a concentration of 50-100 g / l (for a ratio of 4 parts of bentonite to 1 part of humate, 3 parts of APD and 0.4 parts of PEG) and its mechanical stirring for 5- 6 o'clock. After that, the suspension was dried at 70-80 ° C for 6 hours to remove visible traces of moisture. The resulting dried mixture was ground with an impact mill to a powder with a particle size of 5-200 μm.

For introduction into the soil, the resulting preparation was mixed with the final volume of soil taken from the planting zone. The optimum is the introduction of 0.25% of the drug by weight of the soil. In laboratory conditions, the drug was introduced into the soil directly and, by mixing, ensured its uniform distribution in the volume of the soil. When carrying out large-scale experiments (for example, in greenhouses) and working with small doses of the drug, it is possible to premix it with a small volume of soil, and introduce the resulting mixture into the bulk of the soil, followed by mixing it with a cultivator or cutter.

To achieve equilibrium, the soil with the applied preparation was kept for 3 days, after which the seeds were sown into it. It should be noted that in field conditions this fact will not have a significant effect on the effectiveness of the drug, since the development time of plants on which the use of this drug is supposed to be calculated is 2-3 months.

The optimal ratios of the components of the sorption-stimulating drug were determined experimentally. Variants of the ratios of components and doses of application are shown in Table 1.

For comparison (in accordance with the prototype), a control sample was prepared, in which the seeds of the test culture were sown in soil pretreated with activated carbon at the rate of 0.25% of coal by weight of the soil.

All the results of the experiments performed are shown in Table 1.

To assess the effectiveness of the implementation of the proposed method used a technique based on the existence of a linear relationship between the length of seedlings of large arrays of seeds and their bulk volume in water [6]. The known method for evaluating the stimulating activity of drugs-stimulants allows processing large batches of seeds in a short time, which makes it applicable on an industrial scale. The total length of seedlings determines their bulk volume. The longer the seedlings are, the greater the bulk of the germinated seeds. Thus, the change in the bulk volume of germinated seeds characterizes the total length of their seedlings and makes it possible to compare the germinated seeds planted in the soil treated by the claimed method and the seeds planted in the soil treated in accordance with the prototype with respect to untreated soil.

To estimate the length of seedlings for each experimental batch of seeds, the following steps were performed.

The following soil samples were preliminarily prepared:

untreated soil (1 sample, in relation to which the% change in allelotoxicity is given, is not presented in the table due to the absence of the introduction of sorption-stimulating components);

soil treated with activated carbon as follows:

the coal was crushed in an impact mill to a particle size of 5-200 microns;

the resulting powder was taken in an amount providing a ratio of 0.25 part of the preparation per 100 parts of soil;

for uniform application of the selected sample of the powder, it was divided into 4 parts, each of which was applied to the soil surface, thoroughly mixed, and the next portion of the sample was added.

soil treated with the preparation obtained by the claimed method, where the sorption-stimulating preparation is prepared from bentonite, humate, APD and PEG (in the ratio 4: 0.67-1.5: 1.2-3.2: 0.3-0, 5), and the introduction of the drug into the soil was carried out in accordance with paragraphs 2.1.-2.3.

soil treated with a mixture of bentonite, humate, APD and PEG with deviations from the optimal conditions for preparing the drug according to the claimed method (table 1).

When conducting experiments to assess the effect of drugs on reducing the allelotoxicity of soils, 30 g of soil (samples 1, 2, 3, and 4) were placed on the bottom of a dish with a diameter of 95 mm, then 7.5 g of seeds from one batch were placed in an even layer, and on top - 30 g of soil (samples 1, 2, 3, and 4, respectively). After that, water was evenly added to the dish from a measuring pipette. A sixfold repetition was used with subsequent statistical processing of the results.

The seeds germinated in the soil were washed from the soil and placed in portions into a 100 ml measuring cylinder with water, placed on a vibrating table vibrating at a frequency of 50 Hz. After placing each portion of the germinated seeds in a cylinder, which created an openwork porous structure, a small weight of 8 g in the form of a rubber stopper was placed on them for 15-20 seconds, which led to the compaction of the structure. After placing all the germinated seeds in the cylinder, a weight was placed on them and additional compaction of the structure was carried out by lightly tapping (30-40) the cylinder with seeds on the table. These operations made it possible to create a fairly homogeneous structure, and the lower boundary of the load made it possible to determine the bulk volume with an accuracy of 0.5 ml.

Before conducting experiments to assess the reduction of allelotoxicity of soils by the preparations, the optimal initial soil moisture was determined, at which the tests were carried out. For this, according to the method described above, the amount of water added to the soil was determined, which would provide the maximum total length of seedlings planted in untreated soil in 2 days. The optimum amount of water added to the soil was 9 g.

The results of reducing the allelotoxicity of soils by the preparations were expressed as a percentage of the change in the length of seedlings in the treated (prototype or by the claimed method) soil compared to seeds germinated in untreated soil.

From the data obtained, it can be seen that the optimal parameters for introducing the drug into the soil are the ratios of calcium bentonite, humate, APD and PEG equal to 4: 0.9-1.1: 2.8-3.2: 0.35-0.45.

The need for mixing the composition for more than 5 hours is due to the processes of disintegration of aggregates of particles of montmorillonite, which is part of bentonite, to individual particles and an increase in the sorption surface of the preparation.

Table 1

Sample No. as described Preparation (P) Composition of the preparation Time of drug formation while stirring the suspension, hours Water removal temperature from drug suspension, ° С Decrease in allelotoxicity of soils,% The share of bentonite in the preparation, parts The share of humate in the composition of the preparation, parts The share of APD in the composition of the drug, parts The share of PEG in the composition of the drug, parts Consumption of the preparation,% of the weight of the soil 2 sample Activated carbon - - - - 0.25 - 70-80 +3 3 sample P-1 4 0.67 - - 0.25 5-6 70-80 +4 P-2 4 0.9 - - 0.25 5-6 70-80 +8 P-3 4 1 - - 0.25 5-6 70-80 +8 P-4 4 1.1 - - 0.25 5-6 70-80 +8 P-5 4 1.5 - - 0.25 5-6 70-80 +5 P-6 4 1 1,2 - 0.25 5-6 70-80 +13 P-7 4 1 1.8 - 0.25 5-6 70-80 +19 P-8 4 1 2.8 - 0.25 5-6 70-80 +30 P-9 4 1 3.0 - 0.25 5-6 70-80 +30 P-10 4 1 3.2 - 0.25 5-6 70-80 +30 P-11 4 1 3.6 - 0.25 5-6 70-80 +23 P-12 4 1 3.0 0.30 0.25 5-6 70-80 +40 P-13 4 1 3.0 0.35 0.25 5-6 70-80 +45 P-14 4 1 3.0 0.40 0.25 5-6 70-80 +45 P-15 4 1 3.0 0.45 0.25 5-6 70-80 +45 P-16 4 1 3.0 0.50 0.25 5-6 70-80 +40 P-14 4 1 3.0 0.40 0.25 1-2 70-80 +17 P-14 4 1 3.0 0.40 0.25 3-4 70-80 +23 P-14 4 1 3.0 0.40 0.25 7-8 70-80 +45 P-14 4 1 3.0 0.40 0.25 24-28 70-80 +45 P-14 4 1 3.0 0.40 0.25 5-6 100-110 +30 P-14 4 1 3.0 0.40 0.25 5-6 150-160 +25 4 sample 4 1 3 0,4 0.25 0.2 +8

P-1-16 - the numbers of the component compositions of the preparations obtained by the claimed method.

Thus, the proposed invention, when used as a means of soil cultivation, can significantly reduce its allelotoxicity and, due to this, increase the rate of development of plants in the soil from 2% (prototype) to 45% (the claimed method).

Sources of information

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3. Lobkov V.T. The use of soil-biological factor in agriculture: monograph. Orel: Publishing house of the Federal State Budgetary Educational Institution of Higher Education Oryol GAU. 2017.166 p.

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5. Kulikova N.A. binding capacity and detoxifying properties of humic acids in relation to atrazine. Diss. Cand. Biol. Science. M.: Moscow State University. 1999.171 s.

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Claims (4)

1. A method of preparing a complex sorption-stimulating drug for reducing allelotoxicity of the soil, characterized in that aqueous solutions of bentonite, potassium or sodium humate, autolysate of brewer's yeast (APD) and polyethylene glycol (PEG) are mixed in a mass ratio of 4: 0.9-1, 1: 2.8-3.2: 0.35-0.45, respectively, with continuous stirring for 5-6 hours to obtain a suspension, which is dried to obtain a dry residue, followed by grinding into powder. 2. The method according to claim 1, characterized in that the suspension of bentonite, humate, APD and PEG has a concentration of 50-100 g / l. 3. The method according to claim 1, characterized in that the suspension is dried by keeping at a temperature of 70-80 ° C until traces of visible moisture are removed. 4. The method according to claim 1, characterized in that the grinding of the dry residue is carried out with an impact mill to obtain particles with a size of 5-200 microns.