Multifunctional fertilizer synergist and preparation method thereof

Abstract

This invention provides a multifunctional fertilizer synergist and its preparation method. By screening multiple components and optimizing their ratio, a synergistic system of "nutrient controlled release + root induction + stress resistance enhancement" is constructed. At the same time, the preparation process is optimized to achieve component activity retention and green process, solving the technical defects of existing synergists such as single function, poor component compatibility, easy loss of microbial activity, and complex preparation process. This improves fertilizer utilization, improves the soil environment, enhances crop stress resistance, and leaves no harmful residues throughout the process, meeting the needs of green agricultural development.

Description

Technical Field

[0001] This invention belongs to the field of agricultural chemistry and bio-fertilizer technology, specifically relating to a multifunctional fertilizer synergist and its preparation method. Background Technology

[0002] In current agricultural production, low fertilizer utilization efficiency and severe nutrient loss are widespread problems. Traditional nitrogen and potassium fertilizers are easily leached or volatilized by rainwater after application in the field, causing not only huge economic losses but also environmental and agricultural problems such as eutrophication of water bodies, soil compaction, and non-physiological obstacles in crops. To address these challenges, technologies such as controlled-release fertilizers, slow-release additives, and functional synergists are being gradually promoted and applied. Among these, bio-based fertilizer synergists have become a research hotspot in recent years due to their advantages of being derived from natural renewable resources, having good biocompatibility, and being biodegradable with no residue.

[0003] The existing technology CN202511703054.9 discloses a fertilizer synergist based on polyaspartic acid, fucoidan, and mannan oligosaccharide, which only achieves nutrient controlled release and root induction by constructing a complex network of the three, without involving the functions of soil microecological regulation and crop stress resistance enhancement; CN202411034688.5 uses modified polyglutamic acid and biochar as a compound, which has a certain fertilizer retention capacity, but the biochar has poor dispersibility and weak synergistic effect with other components.

[0004] Therefore, developing a bio-based compound fertilizer synergist with multiple components, a green and simple preparation process, the ability to simultaneously enhance nutrient efficiency, improve soil, and improve crop stress resistance, and with good stability of each component and no environmental residues, has become an urgent technical problem to be solved in this field. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a multifunctional fertilizer synergist and its preparation method. By screening multiple components and optimizing their ratios, a synergistic system of "nutrient controlled release + root induction + stress resistance enhancement" is constructed. At the same time, the preparation process is optimized to achieve component activity retention and green process, solving the technical defects of existing synergists such as single function, poor component compatibility, easy loss of microbial activity, and complex preparation process. This improves fertilizer utilization, improves the soil environment, enhances crop stress resistance, and leaves no harmful residues throughout the process, meeting the needs of green agricultural development.

[0006] Specifically, the present invention is achieved through the following technical solution: A multifunctional fertilizer synergist, comprising the following raw material components by weight: 35-55 parts aspartic acid, 10-30 parts glutamic acid, 25-45 parts seaweed extract, 0.3-1.0 parts spermidine, 0.3-1.0 parts γ-aminobutyric acid, and 2-7 parts binder; wherein the binder is a mixture of maltodextrin and sodium carboxymethyl cellulose in a mass ratio of 3-5:1.

[0007] Preferably, the multifunctional fertilizer synergist comprises the following raw material components by weight: The mixture consists of 45 parts aspartic acid, 20 parts glutamic acid, 35 parts seaweed extract, 0.6 parts spermidine, 0.6 parts γ-aminobutyric acid, and 4.5 parts binder. The binder is a mixture of maltodextrin and sodium carboxymethyl cellulose in a mass ratio of 4:1.

[0008] In a second aspect, the present invention provides a method for preparing a multifunctional fertilizer synergist, specifically comprising the following steps: (1) Dissolve aspartic acid and glutamic acid in deionized water, stir until completely dissolved, adjust pH, add phosphoric acid catalyst to the mixed amino acid solution, heat and stir, then cool to room temperature, add deionized water to dilute, filter to remove insoluble impurities, then concentrate under reduced pressure, and finally freeze dry and pulverize to obtain aspartic acid-glutamic acid powder. (2) Mix aspartic acid-glutamic acid powder, seaweed extract, spermidine, γ-aminobutyric acid and some binder evenly, add an appropriate amount of purified water, perform the first granulation, dry and crush, and sieve; then mix with the remaining binder, add an appropriate amount of purified water, perform the second granulation, dry the wet granules, granulate, and sieve to obtain a multifunctional fertilizer synergist.

[0009] Preferably, in step (1), the amount of phosphoric acid catalyst added is 2% to 4% of the total mass of the mixed amino acids; Preferably, in step (1), the pH is adjusted to 7.0–8.0; Preferably, the heating temperature in step (1) is 170–200°C; Preferably, the stirring is carried out for 3 to 5 hours in step (1); Preferably, in step (2), the amount of binder added during the first granulation is 65-75% of the total amount; Preferably, in step (2), the sieve is sieved through a mesh of 80-100.

[0010] In a preferred embodiment, a method for preparing a multifunctional fertilizer synergist specifically includes the following steps: (1) Dissolve aspartic acid and glutamic acid in deionized water, stir until completely dissolved, adjust pH to 7.0-8.0, add 2%-4% phosphoric acid catalyst to the mixed amino acid solution, heat to 170-200℃, stir for 3-5 hours, then cool to room temperature, add deionized water to dilute, filter to remove insoluble impurities, then concentrate under reduced pressure, and finally freeze dry and pulverize to obtain aspartic acid-glutamic acid powder; (2) Mix aspartic acid-glutamic acid powder, seaweed extract, spermidine, γ-aminobutyric acid and 65-75% binder evenly, add an appropriate amount of purified water, perform the first granulation, dry and crush, and pass through an 80-100 mesh sieve; then mix with the remaining 35-45% binder, add an appropriate amount of purified water, perform the second granulation, dry the wet granules, granulate, and pass through an 80-100 mesh sieve to obtain a multifunctional fertilizer synergist.

[0011] The beneficial effects of this invention are: The modification of aspartic acid with glutamic acid and the secondary granulation method result in better nutrient controlled release effect; seaweed extract can activate the expression of crop stress resistance genes, and the combination of γ-aminobutyric acid and spermidine can repair soil and crop micro-ecology, taking into account both crop growth and soil maintenance. Detailed Implementation

[0012] The present invention will be further illustrated below through embodiments. It should be understood that the embodiments of the present invention are merely illustrative and not intended to limit the invention. Therefore, any simple modifications to the present invention based on the method described herein are within the scope of protection claimed by the present invention. Unless otherwise stated, the raw materials and reagents used in the embodiments are commercially available products, and reagents, instruments, or operating procedures not described herein are all matters that can be conventionally determined by those skilled in the art.

[0013] Example 1 A multifunctional fertilizer synergist comprises the following components in parts by weight: 45 parts aspartic acid, 20 parts glutamic acid, 35 parts seaweed extract, 0.6 parts spermidine, 0.6 parts γ-aminobutyric acid, and 4.5 parts binder; wherein the binder is a mixture of maltodextrin and sodium carboxymethyl cellulose in a mass ratio of 4:1.

[0014] Its preparation method includes the following steps: (1) Dissolve aspartic acid and glutamic acid in deionized water, stir until completely dissolved, adjust pH to 7.5, add 3% phosphoric acid catalyst to the mixed amino acid solution, heat to 190℃, stir for 4h, then cool to room temperature, add deionized water to dilute, filter to remove insoluble impurities, then concentrate under reduced pressure, and finally freeze dry and pulverize to obtain aspartic acid-glutamic acid powder; (2) Mix aspartic acid-glutamic acid powder, seaweed extract, spermidine, γ-aminobutyric acid and 70% binder evenly, add an appropriate amount of purified water, perform the first granulation, dry and crush, and pass through an 80-100 mesh sieve; then mix with the remaining 30% binder, add an appropriate amount of purified water, perform the second granulation, dry the wet granules, granulate, and pass through an 80-100 mesh sieve to obtain a multifunctional fertilizer synergist.

[0015] Example 2 A multifunctional fertilizer synergist comprises the following components in parts by weight: 35 parts aspartic acid, 30 parts glutamic acid, 25 parts seaweed extract, 0.3 parts spermidine, 1.0 part γ-aminobutyric acid, and 2 parts binder; wherein the binder is a mixture of maltodextrin and sodium carboxymethyl cellulose in a mass ratio of 5:1.

[0016] A multifunctional fertilizer synergist was prepared according to the method in Example 1.

[0017] Example 3 A multifunctional fertilizer synergist comprises the following components in parts by weight: 55 parts aspartic acid, 10 parts glutamic acid, 45 parts seaweed extract, 1.0 part spermidine, 0.3 parts γ-aminobutyric acid, and 7 parts binder; wherein the binder is a mixture of maltodextrin and sodium carboxymethyl cellulose in a mass ratio of 3:1.

[0018] A multifunctional fertilizer synergist was prepared according to the method in Example 1.

[0019] Comparative Example 1 A multifunctional fertilizer synergist comprises the following components in parts by weight: 45 parts aspartic acid, 35 parts seaweed extract, 0.6 parts spermidine, 0.6 parts γ-aminobutyric acid, and 4.5 parts binder; wherein the binder is a mixture of maltodextrin and sodium carboxymethyl cellulose in a mass ratio of 4:1.

[0020] Its preparation method includes the following steps: Aspartic acid, seaweed extract, spermidine, γ-aminobutyric acid, and 70% binder are mixed evenly, and an appropriate amount of purified water is added for the first granulation. After drying, the mixture is pulverized and passed through an 80-100 mesh sieve. Then, it is mixed with the remaining 30% binder, and an appropriate amount of purified water is added for the second granulation. After the wet granules are dried, they are granulated and passed through an 80-100 mesh sieve to obtain a multifunctional fertilizer synergist.

[0021] Comparative Example 2 A multifunctional fertilizer synergist comprises the following components in parts by weight: 45 parts aspartic acid, 20 parts glutamic acid, 35 parts seaweed extract, 0.6 parts spermidine, and 4.5 parts binder; wherein the binder is a mixture of maltodextrin and sodium carboxymethyl cellulose in a mass ratio of 4:1.

[0022] A multifunctional fertilizer synergist was prepared according to the method in Example 1.

[0023] Comparative Example 3 A multifunctional fertilizer synergist comprises the following components in parts by weight: 45 parts aspartic acid, 20 parts glutamic acid, 0.6 parts spermidine, 0.6 parts γ-aminobutyric acid, and 4.5 parts binder; wherein the binder is a mixture of maltodextrin and sodium carboxymethyl cellulose in a mass ratio of 4:1.

[0024] A multifunctional fertilizer synergist was prepared according to the method in Example 1.

[0025] Comparative Example 4 A multifunctional fertilizer synergist comprises the following components in parts by weight: 45 parts aspartic acid, 20 parts glutamic acid, 35 parts seaweed extract, 0.6 parts spermidine, 0.6 parts γ-aminobutyric acid, and 4.5 parts maltodextrin.

[0026] Its preparation method includes the following steps: (1) Dissolve aspartic acid and glutamic acid in deionized water, stir until completely dissolved, adjust pH to 7.5, add 3% phosphoric acid catalyst to the mixed amino acid solution, heat to 190℃, stir for 4h, then cool to room temperature, add deionized water to dilute, filter to remove insoluble impurities, then concentrate under reduced pressure, and finally freeze dry and pulverize to obtain aspartic acid-glutamic acid powder; (2) Mix aspartic acid-glutamic acid powder, seaweed extract, spermidine, γ-aminobutyric acid and 70% maltodextrin evenly, add an appropriate amount of purified water, perform the first granulation, dry and crush, and pass through an 80-100 mesh sieve; then mix with the remaining 30% maltodextrin, add an appropriate amount of purified water, perform the second granulation, dry the wet granules, granulate, and pass through an 80-100 mesh sieve to obtain a multifunctional fertilizer synergist.

[0027] Comparative Example 5 A multifunctional fertilizer synergist comprises the following components in parts by weight: 45 parts aspartic acid, 20 parts glutamic acid, 35 parts seaweed extract, 0.6 parts spermidine, 0.6 parts γ-aminobutyric acid, and 4.5 parts binder; wherein the binder is a mixture of maltodextrin and sodium carboxymethyl cellulose in a mass ratio of 4:1.

[0028] Its preparation method includes the following steps: Aspartic acid, glutamic acid, seaweed extract, spermidine, γ-aminobutyric acid, and 70% binder are mixed evenly, and an appropriate amount of purified water is added for the first granulation. After drying, the mixture is pulverized and passed through an 80-100 mesh sieve. Then, it is mixed with the remaining 30% binder, and an appropriate amount of purified water is added for the second granulation. After the wet granules are dried, they are granulated and passed through an 80-100 mesh sieve to obtain a multifunctional fertilizer synergist.

[0029] Comparative Example 6 A multifunctional fertilizer synergist comprises the following components in parts by weight: 45 parts aspartic acid, 20 parts glutamic acid, 35 parts seaweed extract, 0.6 parts spermidine, 0.6 parts γ-aminobutyric acid, and 4.5 parts binder; wherein the binder is a mixture of maltodextrin and sodium carboxymethyl cellulose in a mass ratio of 4:1.

[0030] Its preparation method includes the following steps: (1) Dissolve aspartic acid and glutamic acid in deionized water, stir until completely dissolved, adjust pH to 7.5, add 3% phosphoric acid catalyst to the mixed amino acid solution, heat to 190℃, stir for 4h, then cool to room temperature, add deionized water to dilute, filter to remove insoluble impurities, then concentrate under reduced pressure, and finally freeze dry and pulverize to obtain aspartic acid-glutamic acid powder; (2) Mix aspartic acid-glutamic acid powder, seaweed extract, spermidine, γ-aminobutyric acid and binder evenly, add an appropriate amount of purified water, granulate for the first time, dry the wet granules, granulate, and pass through an 80-100 mesh sieve to obtain a multifunctional fertilizer synergist.

[0031] Verification Example: Nitrogen fertilizer controlled release performance test 1000g of samples prepared in Examples 1-3 and Comparative Examples 1-6 were weighed, placed in permeable nonwoven bags and sealed, and then immersed in 250mL of deionized water and allowed to stand at a constant temperature of 25℃. The water was changed every 24 hours, and water samples from the previous cycle were collected. The total nitrogen content was determined using the Kjeldahl method. The experiment lasted for 28 days, and the nitrogen release of each sample at different time points was recorded. The time required to reach 80% cumulative release, i.e., the controlled-release duration, was calculated. The results are shown in Table 1 below.

[0032] Table 1 Controlled Release Time The results showed that Examples 1 to 3 all exhibited good nitrogen controlled release performance. Comparative Example 1 did not add glutamic acid, and Comparative Example 5 did not undergo reaction treatment, resulting in structural loss, rapid initial nitrogen release, and a sharp reduction in the duration of controlled release. Although Comparative Example 6 had the same formula, it did not undergo secondary granulation, and also showed a shortened controlled release time.

[0033] Crop yield increase test Field comparison trials were conducted on samples prepared in Examples 1-3 and Comparative Examples 1-6. The control group was not treated with synergists. The experimental crop was wheat. The soil fertility of the experimental plots was uniform, and the field management measures such as seeding rate, irrigation, and pest and disease control were consistent. The experimental area of ​​each group was 100 m². The experimental results are shown in Table 2 below: Table 2 Soil modification test A random sample of soil was divided into 10 equal portions. The organic matter and microbial content of the soil were first tested. Then, samples from Examples 1-3 and Comparative Examples 1-6 were evenly spread onto the remaining 9 portions of soil. The control group received no synergist. The soil was immediately deep-plown to a depth of 25-30 cm to ensure proper mixing of fertilizer and soil. Sixty days after fertilization, soil samples from the topsoil layer (0-20 cm) were collected using an "S-shaped" method. After thorough mixing, the samples were air-dried, pulverized, and sieved through a 3-5 mm sieve. The soil organic matter content was tested according to GB 9834-1988 standard, and the microbial content was tested according to GB / T 39228-2020 standard, "Determination of Soil Microbial Biomass, Fumigation Extraction Method". The experimental results are shown in Table 3 below. Table 3 The synergists in Examples 1-3 can effectively increase the total amount of soil microorganisms, while in Comparative Example 2, no γ-aminobutyric acid was added, which greatly reduced the effect of the synergist.

Claims

1. A multi-functional fertilizer synergist, characterized in that, The components include the following parts by weight: 35-55 parts aspartic acid, 10-30 parts glutamic acid, 25-45 parts seaweed extract, 0.3-1.0 parts spermidine, 0.3-1.0 parts γ-aminobutyric acid, and 2-7 parts binder; wherein the binder is a mixture of maltodextrin and sodium carboxymethyl cellulose in a mass ratio of 3-5:

1.

2. The fertilizer synergist of claim 1, wherein, The components include the following parts by weight: The mixture consists of 45 parts aspartic acid, 20 parts glutamic acid, 35 parts seaweed extract, 0.6 parts spermidine, 0.6 parts γ-aminobutyric acid, and 4.5 parts binder. The binder is a mixture of maltodextrin and sodium carboxymethyl cellulose in a mass ratio of 4:

1.

3. A method of preparing the fertilizer efficacy enhancer of any one of claims 1-2, characterized in that, The steps include: 1) Dissolving aspartic acid and glutamic acid in deionized water, stirring until completely dissolved, adjusting the pH, adding phosphoric acid catalyst to the mixed amino acid solution, heating and stirring, then cooling to room temperature, adding deionized water to dilute, filtering to remove insoluble impurities, then concentrating under reduced pressure, and finally freeze-drying and pulverizing to obtain aspartic acid-glutamic acid powder. 2) Mix aspartic acid-glutamic acid powder, seaweed extract, spermidine, γ-aminobutyric acid and some binder evenly, add an appropriate amount of purified water, perform the first granulation, dry and crush, and sieve; then mix with the remaining binder, add an appropriate amount of purified water, perform the second granulation, dry the wet granules, granulate, and sieve to obtain a multifunctional fertilizer synergist.

4. The production method according to claim 3, characterized by, In step 1), the amount of phosphoric acid catalyst added is 2% to 4% of the total mass of the mixed amino acids.

5. The preparation method according to claim 3, characterized in that, In step 1), adjust the pH to 7.0–8.

0.

6. The preparation method according to claim 3, characterized in that, The heating temperature in step 1) is 170-200℃.

7. The preparation method according to claim 3, characterized in that, In step 2), the amount of binder added during the first granulation is 65-75% of the total amount.

8. The preparation method according to claim 3, characterized in that, In step 2), sieve through an 80-100 mesh screen.

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