Slow-release and controlled-release compound fertilizer containing multiple nutrient elements and preparation method thereof

Abstract

The invention relates to the technical field of microbial fertilizer manufacturing, in particular to a slow-release and controlled-release compound fertilizer containing multiple nutrient elements and a preparation method of the slow-release and controlled-release compound fertilizer. The invention provides a slow-release and controlled-release compound fertilizer containing multiple nutrient elements, the compound fertilizer comprises macroelements, medium trace elements, a compound microbial agent, a carrier and controlled-release factors, the macroelements comprise nitrogen, phosphorus and potassium; the medium trace elements comprise copper, zinc, manganese, iron, magnesium, sodium, calcium, boron and silicon; the compound microbial agent comprises spore powder of bacillus and spore powder of irpex lacteus; the carrier comprises vermiculite powder, a seaweed fertilizer and humic acid; the controlled release factor comprises silicon dioxide, chitosan, lignin and silicon carbide coupled magnetic beads; the preparation method of the silicon carbide coupled magnetic beads comprises the step of coupling silicon carbide and magnetic beads under the action of percarboxylate and distearoyloxy isopropyl aluminate to obtain the silicon carbide coupled magnetic beads. The compound fertilizer can significantly promote the growth of crops.

Description

Technical Field

[0001] The present invention relates to the technical field of microbial fertilizer manufacturing, and particularly relates to a slow-release and controlled-release compound fertilizer containing multiple nutrient elements and a preparation method thereof. Background Art

[0002] In agricultural production, the rational use of fertilizers is crucial for improving the yield and quality of crops. Traditional fertilizers often only contain main nutrient elements such as nitrogen, phosphorus, and potassium, while ignoring the importance of medium and trace elements for crop growth. In addition, the release rate of traditional fertilizers is relatively fast, resulting in a large amount of nutrients being released in a short period of time, which not only reduces the utilization rate of fertilizers, but also may cause pollution to the soil and groundwater.

[0003] In recent years, with the continuous development of agricultural technology, controlled-release fertilizers have gradually become a research hotspot. Controlled-release fertilizers can adjust the release rate of nutrients according to needs, so that nutrients are continuously and stably supplied during the growth process of crops, thereby improving the utilization rate of fertilizers and reducing environmental pollution.

[0004] However, in the preparation process of existing controlled-release fertilizers, single controlled-release materials are often used or the combination of controlled-release materials is improper, resulting in limited controlled-release effects. At the same time, the carrier materials of fertilizers mostly use inorganic substances, lacking the participation of organic substances, which is not conducive to the improvement of soil structure and the enhancement of microbial activity.

[0005] Therefore, in the technical field of microbial fertilizer manufacturing, it is particularly important to provide an improved controlled-release multi-nutrient compound fertilizer. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide an improved controlled-release multi-nutrient compound fertilizer, which can significantly promote the growth of crops.

[0007] In order to achieve the above purpose, the present invention provides the following technical solutions:

[0008] In the first aspect, the present invention provides a slow-release and controlled-release compound fertilizer containing multiple nutrient elements, the compound fertilizer includes macronutrients, medium and trace elements, compound microbial inoculum, carrier, and controlled-release factor, wherein,

[0009] The macronutrients include nitrogen, phosphorus, and potassium;

[0010] The medium and trace elements include copper, zinc, manganese, iron, magnesium, sodium, calcium, boron, and silicon;

[0011] The composite microbial inoculum includes spore powder of Bacillus and spore powder of Irpex lacteus; the spore powder of Bacillus is the spore powder of Bacillus LY152, and the preservation number of Bacillus LY152 is CGMCC No. 9541; the spore powder of Irpex lacteus is the spore powder of Irpex lacteus PR2, and the preservation number of Irpex lacteus PR2 is CGMCC No. 13190;

[0012] The carrier includes vermiculite powder, seaweed fertilizer and humic acid;

[0013] The controlled release factor includes silicon dioxide, chitosan, lignin and silicon carbide coupled magnetic beads;

[0014] The preparation method of the silicon carbide coupled magnetic beads is: coupling silicon carbide and magnetic beads under the action of percarboxylic acid ester and diisopropyl stearoyl aluminate.

[0015] Preferably, the mass ratio of silicon dioxide, chitosan, lignin and silicon carbide coupled magnetic beads in the controlled release factor is 0.3 - 1:1.2 - 2:2 - 3:3 - 5.

[0016] Preferably, the mass ratio of silicon carbide, magnetic beads, percarboxylic acid ester and diisopropyl stearoyl aluminate in the preparation method of the silicon carbide coupled magnetic beads is 0.3 - 0.8:1:0.3 - 0.5:0.5 - 1.

[0017] Preferably, the mass ratio of vermiculite powder, seaweed fertilizer and humic acid in the carrier is 3 - 5:1:1 - 2.

[0018] Preferably, by mass, the compound fertilizer includes 10 - 20 parts of macronutrients, 5 - 15 parts of medium and micronutrients, 1 - 2 parts of composite microbial inoculum, 3 - 6 parts of carrier and 2 - 5 parts of controlled release factor.

[0019] Preferably, the magnetic beads are polystyrene magnetic beads.

[0020] In the present invention, the effective viable count of Bacillus is not less than 100 million CFU / g, and the effective viable count of Irpex lacteus is not less than 100 million CFU / g.

[0021] The vegetative cells of Bacillus mainly appear rod-shaped or oval-shaped. The rod-shaped can be further divided into long rods and short rods, and the oval-shaped includes long ovals and short ovals. Bacillus is widely present in soil, plants, food, and animal intestines, and its vegetative body divides and proliferates about once every half hour. CN106007950A discloses the application of Bacillus LY152 in the preparation of microbial fertilizers. The preservation number of Bacillus LY152 is CGMCC NO.9541. It can reproduce rapidly and secrete 3-indoleacetic acid, stimulating crop growth so that the crops can fully absorb and utilize the nutrients in the fertilizer. At present, the research on Bacillus LY152 mainly focuses on the role of this microorganism itself, and there is no report on its cooperation with other microorganisms (such as Irpex lacteus).

[0022] Irpex lacteus is a saprophytic fungus. The fruiting body generally grows on the dead wood or rotten wood of broad-leaved trees. This strain contains many nutrients, such as proteins, polysaccharides, polypeptides, etc., and has an immunomodulatory function. At present, the research on Irpex lacteus mainly focuses on the role of this microorganism itself, and there is no report on its cooperation with other microorganisms (such as Bacillus). CN106399132A discloses a strain of Irpex lacteus named Irpex lacteus PR2, and the preservation number of the strain is CGMCC NO.13190. It can promote the growth of crop roots.

[0023] In the present invention, the nitrogen in the macronutrients is derived from urea, the phosphorus in the macronutrients is derived from monoammonium phosphate, the potassium in the macronutrients is derived from potassium sulfate, and the medium and micronutrients are derived from the sulfate series. Further, the present invention does not limit the nitrogen content in urea, the phosphorus content in monoammonium phosphate, or the potassium content in potassium sulfate. Similarly, the present invention also does not limit the copper content, zinc content, manganese content, iron content, magnesium content, sodium content, calcium content, boron content, and silicon content in the sulfate series.

[0024] Second, a preparation method of the compound fertilizer described in the present invention is provided. The preparation method is as follows: After fully mixing the macronutrients, medium and micronutrients, compound microbial inoculant, carrier, and controlled-release factor evenly, add mother liquor water to adjust the pH to neutral, and obtain the product through extrusion granulation and screening.

[0025] Preferably, the mother liquor water is prepared from natural brassinolide and crop root-promoting auxiliaries.

[0026] Preferably, the crop root-promoting auxiliaries include one or more of paclobutrazol, octanoate, Genwang, brassinolide-like, DMPP (nitrification inhibitor), hypersensitive protein, fruit swelling and beautifying agent, phthalanilic acid, ethephon, and chlormequat chloride.

[0027] Preferably, by mass parts, the mother liquor water is prepared from 0.01 - 0.05 parts of natural brassinolide and 2 - 5 parts of crop root growth promoter.

[0028] In the present invention, when the main active components of the compound fertilizer and their mass parts are determined, those skilled in the art can easily obtain the mass parts of the mother liquor water. For example, when the mass parts of macronutrients, medium and micronutrients, compound microbial inoculum, carrier and controlled release factor are determined, those skilled in the art can easily obtain the mass parts of the mother liquor water. The compound fertilizer of the present invention is diluted with water at a ratio of 1:50 - 70 (mass ratio).

[0029] In the third aspect, a fertilizer for promoting the growth of crops is provided, including the compound fertilizer of the present invention.

[0030] In the fourth aspect, the application of the compound fertilizer of the present invention in promoting the growth of crops is provided.

[0031] In the fifth aspect, the application of the compound fertilizer of the present invention in improving the resistance of green onions to purple spot disease is provided.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] (1) The slow-release and controlled-release compound fertilizer containing multiple nutrient elements of the present invention can significantly promote the growth of crops by using a controlled release factor including silicon dioxide, chitosan, lignin and silicon carbide coupled magnetic beads. The applicant speculates that this may be because there are a large number of amino and hydroxyl active groups in the chitosan molecule, and these groups can undergo hydrolysis and condensation polymerization reactions with silicon dioxide precursors (such as tetraethyl orthosilicate TEOS) to form hydrogen bond interactions, gradually constructing a network structure of composite sol. In addition, the active groups in the lignin structure may interact with chitosan or silicon dioxide (such as hydrogen bonds, van der Waals forces, etc.), further enhancing the stability of the network structure. Moreover, the silicon carbide coupled magnetic beads combine the hardness and wear resistance of silicon carbide. In the network structure, the silicon carbide coupled magnetic beads may play the role of an "enhanced intelligent component", further improving the stability of the network structure.

[0034] (2) Since macronutrients, medium and micronutrients, compound microbial inoculum and carrier are present in the above network structure, the fertilizer can be filled in the network structure composed of the controlled release factor. On the one hand, the network structure of the present invention allows the slow penetration of water and nutrients, which helps to form a slow-release effect, enabling the nutrients in the fertilizer to be slowly released to the crops. On the other hand, the network structure can form a protective film covering the surface of the fertilizer particles, delaying the release rate of the fertilizer.

[0035] (3) The coupling of silicon carbide and magnetic beads may change the surface properties of the magnetic beads, thereby affecting their interaction with fertilizers and the controlled-release effect. In the present invention, percarboxylic esters and diisopropyl stearoyl aluminate are selected to enhance the binding force between silicon carbide particles and magnetic beads, so as to form stable silicon carbide-coupled magnetic beads, enabling the silicon carbide-coupled magnetic beads of the present invention to maintain a long service life in fertilizers. Their presence can slow down the wear and breakage speed of fertilizer particles, thereby extending the release period of fertilizers; it also helps to prevent the nutrients in fertilizers from being decomposed or lost too quickly during the release process; thus ensuring the controlled-release effect of fertilizers, improving the utilization rate of fertilizers, and having a good yield increase effect.

[0036] (4) The type of magnetic beads also affects the effect of compound fertilizers, which is mainly due to the physical and chemical properties of the magnetic beads themselves. The magnetic beads may interact with other components in fertilizers (such as macronutrients, medium and micronutrients, carriers, etc.), thereby affecting the structure and performance of fertilizers. This interaction may affect the dissolution rate, release mode of fertilizers, and the absorption efficiency of plants for nutrients. The polystyrene magnetic beads selected in the present invention can better delay the release rate of fertilizers and promote the absorption rate of nutrients by crops. These magnetic beads interact with water, nutrients, and microorganisms in the soil, etc.; these interactions may further affect the release rate and mode of fertilizers, making the nutrients more in line with the actual needs of crops.

[0037] (5) The cooperation of the compound microbial inoculant and the network structure, as well as the special role of the controlled-release factor, jointly endow the compound fertilizer of the present invention with slow-release and controlled-release properties. This property helps to reduce the loss and waste of nutrients, improve the utilization rate of fertilizers, and the yield and quality of crops.

[0038] (6) The compound fertilizer of the present invention indirectly or directly improves the resistance of green onions to purple spot disease by providing comprehensive nutrient elements, regulating the nutrient release rate, improving the soil environment, and enhancing the overall health of plants. Specific Embodiments

[0039] The following will specifically describe the present invention in combination with specific embodiments and examples, and the advantages and various effects of the present invention will be presented more clearly therefrom. Those skilled in the art should understand that these specific embodiments and examples are used to illustrate the present invention, rather than to limit the present invention.

[0040] Next, the technical solutions of the present invention will be described in combination with examples. However, the present invention is not limited to the following examples. The experimental methods and detection methods described in each example are conventional methods unless otherwise specified; the reagents and materials described are commercially available unless otherwise specified.

[0041] Bacillus LY152 and Irpex lacteus PR2 were obtained through donation. The preservation number of Bacillus LY152 is CGMCC No. 9541, and the preservation number of Irpex lacteus PR2 is CGMCC No. 13190. For the record of Bacillus LY152, refer to Patent CN106007950A, and for the record of Irpex lacteus PR2, refer to Patent CN106399132A.

[0042] The method for preparing the spore powder of Bacillus LY152 is as follows:

[0043] Inoculate Bacillus LY152 into a nutrient-rich medium (100 g of soy peptone, 5 g of beef extract, 5 g of yeast extract, 5 g of sodium chloride, 1000 mL of distilled water), and culture it at 55 °C and 200 rpm / min for 12 h; the above steps can be repeated to obtain sufficient nutrient cell culture solution.

[0044] Add the nutrient cell culture solution to an inorganic ion medium (1 g of NaCl, 1 g of MnSO4·H2O, 0.5 g of MgSO4·2H2O, 0.05 g of CaCl2·2H2O, 0.05 g of KH2PO4, 1000 mL of distilled water, pH 7.2 - 7.5), and culture it at 60 °C and 150 rpm / min for 12 h; then add a certain amount of inorganic ion medium at regular intervals (such as every 12 h) until the total mass fraction of the added inorganic ion medium and the mass fraction of the nutrient-rich medium reach 8:1; during this process, Bacillus LY152 will gradually transform into spores.

[0045] Centrifuge the spores at 5000 r / min to collect the precipitate, and perform low-temperature (such as 30 - 40 °C) drying treatment on the collected precipitate to obtain the spore powder of Bacillus LY152 with a spore concentration of 2.5×10 8 spores / g.

[0046] The method for preparing the spore powder of Irpex lacteus PR2 is as follows:

[0047] Inoculate the strain of Irpex lacteus PR2 onto a basic medium (200 g of potato, 20 g of glucose, 20 g of agar, 1000 mL of water) for activation culture until the strain grows; inoculate the activated strain into a first fermentation medium (3% glucose, 2% peptone, 0.2% KH2PO4, 0.1% MgSO4, the balance is water) for seed culture to obtain sufficient seed culture solution.

[0048] Inoculate the seed culture solution into the second fermentation medium (1.5% glucose, 1.5% starch, 2% wheat bran juice, 5% soybean cake powder, 0.2% CaCl2, 0.2% KH2PO4, 0.15% MgSO4, and the balance is water), and culture it at 30 °C and 150 rpm / min for 5 days. In the later stage of fermentation culture, the formation of spores by Irpex lacteus PR2 can be induced by adjusting conditions such as the medium composition, temperature, and humidity.

[0049] Centrifuge to collect spores at 5000 r / min, and purify the collected spores to remove impurities and bacteria that have not formed spores; subject the purified spores to low-temperature drying (such as 30 - 40 °C) to remove moisture and maintain the activity of the spores; obtain spore powder of Irpex lacteus PR2 with a spore concentration of 3×10 8 spores per gram.

[0050] Example 1

[0051] This example provides a slow-release and controlled-release compound fertilizer containing multiple nutrient elements. By mass, the compound fertilizer includes 10 parts of macronutrients, 5 parts of medium and micronutrients, 1 part of compound microbial inoculant, 3 parts of carrier, and 2 parts of controlled-release factor;

[0052] The macronutrients include nitrogen, phosphorus, and potassium;

[0053] The medium and micronutrients include copper, zinc, manganese, iron, magnesium, sodium, calcium, boron, and silicon;

[0054] The compound microbial inoculant includes spore powder of Bacillus and spore powder of Irpex lacteus; the spore powder of Bacillus is the spore powder of Bacillus LY152, and the preservation number of Bacillus LY152 is CGMCC No. 9541; the spore powder of Irpex lacteus is the spore powder of Irpex lacteus PR2, and the preservation number of Irpex lacteus PR2 is CGMCC No. 13190;

[0055] The carrier includes vermiculite powder, seaweed fertilizer, and humic acid;

[0056] The controlled-release factor includes silicon dioxide, chitosan, lignin, and silicon carbide-coupled magnetic beads;

[0057] The preparation method of the silicon carbide-coupled magnetic beads is as follows: silicon carbide and polystyrene magnetic beads are coupled under the action of percarboxylic ester and diisopropyl stearoyl aluminate; the mass ratio of silicon carbide, polystyrene magnetic beads, percarboxylic ester, and diisopropyl stearoyl aluminate is 0.3:1:0.3:0.5;

[0058] The mass ratio of silicon dioxide, chitosan, lignin, and silicon carbide-coupled magnetic beads in the controlled-release factor is 0.3:1.2:2:3;

[0059] The mass ratio of vermiculite powder, seaweed fertilizer and humic acid in the carrier is 3:1:1.

[0060] Example 2

[0061] This example provides a slow-release and controlled-release compound fertilizer containing multiple nutrient elements. By mass, the compound fertilizer includes 20 parts of macronutrients, 15 parts of medium and micronutrients, 2 parts of compound microbial inoculum, 6 parts of carrier and 5 parts of controlled-release factor;

[0062] The macronutrients include nitrogen, phosphorus and potassium;

[0063] The medium and micronutrients include copper, zinc, manganese, iron, magnesium, sodium, calcium, boron and silicon;

[0064] The compound microbial inoculum includes spore powder of Bacillus and spore powder of Irpex lacteus. The spore powder of Bacillus is the spore powder of Bacillus LY152, and the preservation number of Bacillus LY152 is CGMCC No.9541; the spore powder of Irpex lacteus is the spore powder of Irpex lacteus PR2, and the preservation number of Irpex lacteus PR2 is CGMCC No.13190;

[0065] The carrier includes vermiculite powder, seaweed fertilizer and humic acid;

[0066] The controlled-release factor includes silicon dioxide, chitosan, lignin and silicon carbide-coupled magnetic beads;

[0067] The preparation method of the silicon carbide-coupled magnetic beads is: coupling silicon carbide and polystyrene magnetic beads under the action of percarboxylic acid ester and diisopropyl stearoyl aluminate; the mass ratio of silicon carbide, polystyrene magnetic beads, percarboxylic acid ester and diisopropyl stearoyl aluminate is 0.8:1:0.5:1;

[0068] The mass ratio of silicon dioxide, chitosan, lignin and silicon carbide-coupled magnetic beads in the controlled-release factor is 1:2:3:5;

[0069] The mass ratio of vermiculite powder and humic acid in the carrier is 5:1:2.

[0070] Example 3

[0071] This example provides a slow-release and controlled-release compound fertilizer containing multiple nutrient elements. By mass, the compound fertilizer includes 15 parts of macronutrients, 11 parts of medium and micronutrients, 2 parts of compound microbial inoculum, 4 parts of carrier and 3 parts of controlled-release factor;

[0072] The macronutrients include nitrogen, phosphorus and potassium;

[0073] The medium and micronutrients include copper, zinc, manganese, iron, magnesium, sodium, calcium, boron and silicon;

[0074] The composite microbial inoculant includes spore powder of Bacillus and spore powder of Irpex lacteus; the spore powder of Bacillus is the spore powder of Bacillus LY152, and the preservation number of Bacillus LY152 is CGMCC No. 9541; the spore powder of Irpex lacteus is the spore powder of Irpex lacteus PR2, and the preservation number of Irpex lacteus PR2 is CGMCC No. 13190;

[0075] The carrier includes vermiculite powder, seaweed fertilizer and humic acid;

[0076] The controlled release factor includes silicon dioxide, chitosan, lignin and silicon carbide coupled magnetic beads;

[0077] The preparation method of the silicon carbide coupled magnetic beads is as follows: silicon carbide and polystyrene magnetic beads are coupled under the action of percarboxylic acid ester and diisopropyl stearoyl aluminate; the mass ratio of silicon carbide, polystyrene magnetic beads, percarboxylic acid ester and diisopropyl stearoyl aluminate is 0.5:1:0.3:0.6;

[0078] In the controlled release factor, the mass ratio of silicon dioxide, chitosan, lignin and silicon carbide coupled magnetic beads is 0.5:1.2:2.5:4;

[0079] In the carrier, the mass ratio of vermiculite powder, seaweed fertilizer and humic acid is 4:1:2.

[0080] Example 4

[0081] This example provides a preparation method of a slow-release and controlled-release compound fertilizer containing multiple nutrient elements. The preparation method is as follows: macronutrients, medium and micronutrients, composite microbial inoculant, carrier and controlled release factor are fully mixed evenly in a mixer, then mother liquor water is added to adjust the pH to neutral, and after extrusion granulation, granules with a diameter of 2.5 - 3 mm are obtained, and then physical cooling, screening of granules and quantitative packaging are carried out;

[0082] By mass, the mother liquor water is prepared from 0.01 - 0.05 parts of natural brassinolide and 2 - 5 parts of Genwang.

[0083] Comparative Example 1

[0084] This comparative example is the same as Example 3, the difference is that chitosan is replaced by cellulose.

[0085] Comparative Example 2

[0086] This comparative example is the same as Example 3, the difference is that silicon carbide is not coupled with magnetic beads.

[0087] Comparative Example 3

[0088] This comparative example is the same as Example 3, the difference is that silicon dioxide is not added.

[0089] Experiment 1: Application Effect

[0090] Test Samples: Compound fertilizers prepared from Examples 1 - 3 and Comparative Examples 1 - 3 according to the preparation method of Example 4. When using the test samples, dilute them 60 times with water.

[0091] Experimental Method: Use 50 kg of the compound fertilizer of the present invention. The experiment was carried out in Meijin Vegetable Plantation, Zhouzhi County, Xi'an City, Shaanxi Province. There are 6 plots in total for the experiment, with a 60 - cm interval between each plot. No replicates are set. The tested crop is pepper Zhongjiao No. 106, and it is managed according to the conventional method. All experimental management methods are the same. After the peppers are harvested, measure the yield per single plant and the number of peppers per single plant obtained from the 6 plots respectively.

[0092] Experimental Results: As shown in Table 1 below.

[0093] Table 1 Application Effects of Compound Fertilizers in Each Group

[0094] Experimental group Yield per plant (g / plant) Number of peppers per plant (peppers / plant) Example 1 406 36 Example 2 403 33 Example 3 411 38 Comparative example 1 201 20 Comparative example 2 200 18 Comparative example 3 187 16

[0095] Similarly, to further illustrate the beneficial effects of the present invention, the following comparative examples are provided:

[0096] Provide Comparative Example 1.1. Compared with Example 3, the difference in this Comparative Example 1.1 is that the silica of the present invention is replaced by mesoporous spherical silica;

[0097] Provide Comparative Example 1.2. Compared with Example 3, the difference in this Comparative Example 1.2 is that the polystyrene magnetic beads of the present invention are replaced by iron hydroxide magnetic beads;

[0098] Provide Comparative Example 1.3. Compared with Example 3, the difference in this Comparative Example 1.3 is that the lignin of the present invention is replaced by cellulose;

[0099] Provide Comparative Example 1.4. Compared with Example 3, the difference in this Comparative Example 1.4 is that the percarboxylate of the present invention is replaced by acetate;

[0100] Provide Comparative Example 1.5. Compared with Example 3, the difference in this Comparative Example 1.5 is that the aluminum diisostearoyl oxyisopropyl aluminate of the present invention is replaced by aluminum distearate;

[0101] Provide Comparative Example 1.6. Compared with Example 3, the difference in this Comparative Example 1.6 is that the vermiculite powder of the present invention is replaced by perlite powder, bentonite, diatomite or biochar;

[0102] Provide Comparative Example 1.7. Compared with Example 3, the difference in this Comparative Example 1.7 is that the humic acid of the present invention is replaced by citric acid, tartaric acid, peat or weathered coal;

[0103] The compound fertilizer is prepared by combining with the preparation method of the present invention and tested according to the test method of Experiment 1. Observe the application effects of the compound fertilizers prepared in Comparative Example 1.1, Comparative Example 1.2, Comparative Example 1.3, Comparative Example 1.4, Comparative Example 1.5, Comparative Example 1.6, and Comparative Example 1.7. The results are similar to those in Comparative Example 1 above.

[0104] Similarly, in order to further illustrate the beneficial effects of the present invention, the following comparative examples are provided:

[0105] Provide Comparative Example 3.1. Compared with Example 3, the difference in this Comparative Example 3.1 is that chitosan is not added;

[0106] Provide Comparative Example 3.2. Compared with Example 3, the difference in this Comparative Example 3.2 is that lignin is not added;

[0107] Provide Comparative Example 3.3. Compared with Example 3, the difference in this Comparative Example 3.3 is that silicon carbide-coupled magnetic beads are not added;

[0108] Provide Comparative Example 3.4. Compared with Example 3, the difference in this Comparative Example 3.4 is that vermiculite powder is not added;

[0109] Provide Comparative Example 3.5. Compared with Example 3, the difference in this Comparative Example 3.5 is that humic acid is not added;

[0110] The compound fertilizer is prepared by combining with the preparation method of the present invention and tested according to the test method of Experiment 1. Observe the application effects of the compound fertilizers prepared in Comparative Example 3.1, Comparative Example 3.2, Comparative Example 3.3, Comparative Example 3.4, and Comparative Example 3.5. The results are similar to those in Comparative Example 3 above.

[0111] As can be seen from Table 1:

[0112] From the application effects, it can be seen that the yield per plant of the peppers applied with the compound fertilizer of the present invention is 403 - 411, which is better than that of the compound fertilizer without applying the formula system of the present invention. The number of peppers per plant of the peppers applied with the compound fertilizer of the present invention is 33 - 38, which is better than the number of peppers per plant of the compound fertilizer without applying the formula system of the present invention. It can be seen that the compound fertilizer of the present invention has a more significant effect in effectively promoting the growth of peppers and increasing the yield of peppers.

[0113] Experiment 2: Controlled release effect test

[0114] Test samples: The compound fertilizers prepared from Examples 1 - 3 and Comparative Examples 1 - 3 according to the preparation method of Example 4.

[0115] Experimental method: Test the nutrient release performance according to "Controlled Release Fertilizer (HG / T4215 - 2011)".

[0116] Test results:

[0117] Example 1: The release period is 105 days, the initial nutrient release rate is 0.77%, the cumulative nutrient release rate at 28 days is 22.23%, and the cumulative nutrient release rate at 105 days is 81.13%. That is, the nutrient release period of this compound fertilizer is 105 days.

[0118] Example 2: The release period is 103 days, the initial nutrient release rate is 0.89%, the cumulative nutrient release rate at 28 days is 25.27%, and the cumulative nutrient release rate at 103 days is 80.61%. That is, the nutrient release period of this compound fertilizer is 103 days.

[0119] Example 3: The release period is 112 days, the initial nutrient release rate is 0.51%, the cumulative nutrient release rate at 28 days is 19.36%, and the cumulative nutrient release rate at 112 days is 80.27%. That is, the nutrient release period of this compound fertilizer is 112 days.

[0120] Comparative Example 1: The release period is 50 days, the initial nutrient release rate is 4.23%, the cumulative nutrient release rate at 28 days is 56.32%, and the cumulative nutrient release rate at 50 days is 82.70%. That is, the nutrient release period of this compound fertilizer is 50 days.

[0121] Comparative Example 2: The release period is 55 days, the initial nutrient release rate is 3.66%, the cumulative nutrient release rate at 28 days is 53.28%, and the cumulative nutrient release rate at 55 days is 83.11%. That is, the nutrient release period of this compound fertilizer is 55 days.

[0122] Comparative Example 3: The release period is 52 days, the initial nutrient release rate is 5.28%, the cumulative nutrient release rate at 28 days is 46.51%, and the cumulative nutrient release rate at 52 days is 83.43%. That is, the nutrient release period of this compound fertilizer is 52 days.

[0123] Similarly, to further illustrate the beneficial effects of the present invention, the following comparative examples are provided:

[0124] Provide Comparative Example 1.1. Compared with Example 3, the difference of this Comparative Example 1.1 is that: the silica of the present invention is replaced by mesoporous spherical silica;

[0125] Provide Comparative Example 1.2. Compared with Example 3, the difference of this Comparative Example 1.2 is that: the polystyrene magnetic beads of the present invention are replaced by iron hydroxide magnetic beads;

[0126] Provide Comparative Example 1.3. Compared with Example 3, the difference of this Comparative Example 1.3 is that: the lignin of the present invention is replaced by cellulose;

[0127] Provide Comparative Example 1.4. Compared with Example 3, the difference of this Comparative Example 1.4 is that: the percarboxylic acid ester of the present invention is replaced by acetate;

[0128] Provide Comparative Example 1.5. Compared with Example 3, the difference in this Comparative Example 1.5 is that the distearoyl oxyisopropyl aluminate of the present invention is replaced by distearoyl oxyaluminum;

[0129] Provide Comparative Example 1.6. Compared with Example 3, the difference in this Comparative Example 1.6 is that the vermiculite powder of the present invention is replaced by perlite powder, bentonite, diatomite or biomass charcoal;

[0130] Provide Comparative Example 1.7. Compared with Example 3, the difference in this Comparative Example 1.7 is that the humic acid of the present invention is replaced by citric acid, tartaric acid, peat or weathered coal;

[0131] Prepare compound fertilizers by combining with the preparation method of the present invention and test according to the test method of Experiment 2. Observe the controlled release effects of the compound fertilizers prepared in Comparative Example 1.1, Comparative Example 1.2, Comparative Example 1.3, Comparative Example 1.4, Comparative Example 1.5, Comparative Example 1.6 and Comparative Example 1.7. The results are similar to those in Comparative Example 1 above.

[0132] Similarly, in order to further illustrate the beneficial effects of the present invention, the following comparative examples are provided:

[0133] Provide Comparative Example 3.1. Compared with Example 3, the difference in this Comparative Example 3.1 is that chitosan is not added;

[0134] Provide Comparative Example 3.2. Compared with Example 3, the difference in this Comparative Example 3.2 is that lignin is not added;

[0135] Provide Comparative Example 3.3. Compared with Example 3, the difference in this Comparative Example 3.3 is that silicon carbide coupled magnetic beads are not added;

[0136] Provide Comparative Example 3.4. Compared with Example 3, the difference in this Comparative Example 3.4 is that vermiculite powder is not added;

[0137] Provide Comparative Example 3.5. Compared with Example 3, the difference in this Comparative Example 3.5 is that humic acid is not added;

[0138] Prepare compound fertilizers by combining with the preparation method of the present invention and test according to the test method of Experiment 2. Observe the controlled release effects of the compound fertilizers prepared in Comparative Example 3.1, Comparative Example 3.2, Comparative Example 3.3, Comparative Example 3.4 and Comparative Example 3.5. The results are similar to those in Comparative Example 3 above.

[0139] It can be seen from Experiment 2 that:

[0140] Since the fertilizer of the present invention can be filled in the network structure composed of controlled-release factors, the network structure of the present invention allows the slow penetration of water and nutrients, which helps to form a slow-release effect, enabling the nutrients in the fertilizer to be slowly released to the crops. On the other hand, the network structure can form a protective film covering the surface of the fertilizer particles, delaying the release rate of the fertilizer. In addition, the percarboxylic acid ester and diisopropyl stearoyl aluminate selected in the present invention can enhance the binding force between the silicon carbide particles and the magnetic beads, forming stable silicon carbide-coupled magnetic beads, so that the silicon carbide-coupled magnetic beads of the present invention can maintain a long service life in the fertilizer. Their presence can slow down the wear and breakage speed of the fertilizer particles, thereby extending the release period of the fertilizer; it also helps to prevent the nutrients in the fertilizer from being decomposed or lost too quickly during the release process; thus ensuring the controlled-release effect of the fertilizer, improving the utilization rate of the fertilizer, and having a good yield increase effect.

[0141] Experiment 3: Test on the effect of green onions against Alternaria porri

[0142] Test samples: Compound fertilizers prepared according to the preparation method of Example 4 from Examples 1-3 and Comparative Examples 1-3.

[0143] Experimental method: Use 50 kg of the compound fertilizer of the present invention. The test was carried out in a vegetable plantation in Zhouzhi County, Xi'an City, Shaanxi Province. Before planting green onions in the experimental group, half of it was evenly spread in the ridges for green onion planting, and the other half was evenly applied near the roots of the green onion seedlings in the experimental group. 1200 green onion seedlings were evenly divided into 6 groups for the experiment. The tested crop was iron rod green onions, and they were managed according to the conventional method. All experimental management methods were the same.

[0144] Experimental results: As shown in Table 2 below.

[0145] Table 2 Effect of compound fertilizers in each group on the resistance of green onions to Alternaria porri

[0146] Experimental group Non-diseased / plant Diseased / plant Prevalence rate / % Example 1 197 3 1.5 Example 2 196 4 2 Example 3 200 0 0 Comparative example 1 132 68 34 Comparative example 2 126 74 37 Comparative example 3 130 70 35

[0147] Similarly, in order to further illustrate the beneficial effects of the present invention, the following comparative examples are provided:

[0148] Provide Comparative Example 1.1. Compared with Example 3, the difference in this Comparative Example 1.1 is that the silica of the present invention is replaced by mesoporous spherical silica;

[0149] Provide Comparative Example 1.2. Compared with Example 3, the difference in this Comparative Example 1.2 is that the polystyrene magnetic beads of the present invention are replaced by iron hydroxide magnetic beads;

[0150] Provide Comparative Example 1.3. Compared with Example 3, the difference in this Comparative Example 1.3 is that the lignin of the present invention is replaced by cellulose;

[0151] Provide Comparative Example 1.4. Compared with Example 3, the difference in this Comparative Example 1.4 is that the percarboxylic acid ester of the present invention is replaced with acetate;

[0152] Provide Comparative Example 1.5. Compared with Example 3, the difference in this Comparative Example 1.5 is that the aluminum distearoyloxyisopropyl aluminate of the present invention is replaced with aluminum distearate;

[0153] Provide Comparative Example 1.6. Compared with Example 3, the difference in this Comparative Example 1.6 is that the vermiculite powder of the present invention is replaced with perlite powder, bentonite, diatomite or biomass charcoal;

[0154] Provide Comparative Example 1.7. Compared with Example 3, the difference in this Comparative Example 1.7 is that the humic acid of the present invention is replaced with citric acid, tartaric acid, peat or weathered coal;

[0155] Prepare compound fertilizers by combining with the preparation method of the present invention and test them according to the test method of Experiment 3. Observe the disease resistance effects of the compound fertilizers prepared in Comparative Example 1.1, Comparative Example 1.2, Comparative Example 1.3, Comparative Example 1.4, Comparative Example 1.5, Comparative Example 1.6, and Comparative Example 1.7. The results are similar to those in Comparative Example 1 above.

[0156] Similarly, in order to further illustrate the beneficial effects of the present invention, the following comparative examples are provided:

[0157] Provide Comparative Example 3.1. Compared with Example 3, the difference in this Comparative Example 3.1 is that chitosan is not added;

[0158] Provide Comparative Example 3.2. Compared with Example 3, the difference in this Comparative Example 3.2 is that lignin is not added;

[0159] Provide Comparative Example 3.3. Compared with Example 3, the difference in this Comparative Example 3.3 is that silicon carbide-coupled magnetic beads are not added;

[0160] Provide Comparative Example 3.4. Compared with Example 3, the difference in this Comparative Example 3.4 is that vermiculite powder is not added;

[0161] Provide Comparative Example 3.5. Compared with Example 3, the difference in this Comparative Example 3.5 is that humic acid is not added;

[0162] Prepare compound fertilizers by combining with the preparation method of the present invention and test them according to the test method of Experiment 3. Observe the disease resistance effects of the compound fertilizers prepared in Comparative Example 3.1, Comparative Example 3.2, Comparative Example 3.3, Comparative Example 3.4, and Comparative Example 3.5. The results are similar to those in Comparative Example 3 above.

[0163] As can be seen from Table 2, the rate of welsh onion suffering from Alternaria leaf spot after applying the compound fertilizer of the present invention is 0-2, and the disease resistance effect is very significant, which is better than that of the compound fertilizer without applying the formula system of the present invention. It can be seen that the compound fertilizer of the present invention can increase the ability of welsh onion to resist Alternaria leaf spot, thereby improving the cultivation effect of welsh onion.

[0164] As can be seen from Experiments 1-3, the compound fertilizer of the present invention can significantly promote the growth of crops by using controlled-release factors including silica, chitosan, lignin and silicon carbide-coupled magnetic beads. The applicant speculates that this may be because there are a large number of amino and hydroxyl active groups in the chitosan molecule, and these groups can undergo hydrolysis and condensation polymerization reactions with silica precursors (such as tetraethyl orthosilicate TEOS) to form hydrogen bond interactions and gradually construct a composite sol with a network structure. In addition, the active groups in the lignin structure may interact with chitosan or silica (such as hydrogen bonds, van der Waals forces, etc.), further enhancing the stability of the network structure. Moreover, the silicon carbide-coupled magnetic beads combine the hardness and wear resistance of silicon carbide. In the network structure, the silicon carbide-coupled magnetic beads may play the role of an "enhanced intelligent component", further improving the stability of the network structure.

[0165] Since macronutrients, medium and micronutrients, compound microbial inoculants, and carriers exist in the above network structure, the fertilizer can be filled in the network structure composed of controlled-release factors. On the one hand, the network structure of the present invention allows the slow penetration of water and nutrients, which helps to form a slow-release effect, enabling the nutrients in the fertilizer to be slowly released to the crops. On the other hand, the network structure can form a protective film covering the surface of the fertilizer particles, delaying the release rate of the fertilizer.

[0166] The coupling of silicon carbide and magnetic beads may change the surface properties of the magnetic beads, thereby affecting their interaction with the fertilizer and the controlled-release effect. The present invention selects percarboxylic acid ester and diisopropyl stearoyl aluminate to enhance the binding force between silicon carbide particles and magnetic beads, enabling them to form stable silicon carbide-coupled magnetic beads, so that the silicon carbide-coupled magnetic beads of the present invention can maintain a long service life in the fertilizer. Their presence can slow down the wear and breakage speed of the fertilizer particles, thereby extending the release period of the fertilizer; it also helps to prevent the nutrients in the fertilizer from being decomposed or lost too quickly during the release process; thus ensuring the controlled-release effect of the fertilizer, improving the utilization rate of the fertilizer, and having a good yield-increasing effect.

[0167] The types of magnetic beads can also affect the effect of compound fertilizers, which is mainly due to the physical and chemical properties of the magnetic beads themselves. The magnetic beads may interact with other components in the fertilizer (such as macronutrients, medium and micronutrients, carriers, etc.), thus affecting the structure and performance of the fertilizer. Such interactions may affect the dissolution rate, release pattern of the fertilizer and the nutrient absorption efficiency of plants. The polystyrene magnetic beads selected in the present invention can better delay the release rate of the fertilizer and promote the nutrient absorption rate of crops. These magnetic beads interact with water, nutrients, microorganisms, etc. in the soil; these interactions may further affect the release rate and pattern of the fertilizer, making the nutrients more in line with the actual needs of the crops.

[0168] The combination of the compound microbial inoculant and the network structure, as well as the special function of the controlled release factor, endow the compound fertilizer of the present invention with slow-release and controlled-release properties. Such properties help to reduce the loss and waste of nutrients, and improve the utilization rate of fertilizers and the yield and quality of crops.

[0169] The compound fertilizer of the present invention indirectly or directly improves the resistance of scallions to purple spot disease in various ways, such as providing comprehensive nutrient elements, regulating the nutrient release rate, improving the soil environment and enhancing the overall health of plants.

[0170] It should be understood that the present invention disclosed is not limited to the specific methods, schemes and substances described, as these can vary. It should also be understood that the terms used herein are for the purpose of describing specific embodiments only and are not intended to limit the scope of the present invention, the scope of which is limited only by the appended claims.

[0171] Those skilled in the art will also recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. These equivalents are also included in the appended claims. It should be noted that each embodiment in this specification is described in a progressive manner, and the key point of each embodiment is to illustrate the differences from other embodiments. The same and similar parts among the various embodiments can be referred to each other.

Claims

1. A compound fertilizer containing multiple nutrient elements with slow release and controlled release, characterized in that: The compound fertilizer includes macroelements, medium and trace elements, composite microbial agents, carriers and controlled release factors, wherein: The macronutrients include nitrogen, phosphorus and potassium; The trace elements include copper, zinc, manganese, iron, magnesium, sodium, calcium, boron and silicon; The composite microbial inoculant comprises spore powder of Bacillus and spore powder of white capsule rake tooth fungus; the spore powder of Bacillus is spore powder of Bacillus LY152, and the preservation number of Bacillus LY152 is CGMCC No.9541; the spore powder of white capsule rake tooth fungus is spore powder of white capsule rake tooth fungus PR2, and the preservation number of white capsule rake tooth fungus PR2 is CGMCC No.13190; The carrier includes vermiculite powder, seaweed fertilizer and humic acid; The controlled release factors include silicon dioxide, chitosan, lignin and silicon carbide coupled magnetic beads; The preparation method of the silicon carbide coupled magnetic beads is as follows: silicon carbide and magnetic beads are coupled under the action of percarboxylic acid ester and distearoyloxyisopropylaluminate to obtain the obtained beads.

2. The compound fertilizer according to claim 1, characterized in that The mass ratio of silicon dioxide, chitosan, lignin and silicon carbide coupled magnetic beads in the controlled release factor is 0.3-1:1.2-2:2-3:3-5.

3. The compound fertilizer according to claim 1, characterized in that In the preparation method of silicon carbide coupled magnetic beads, the mass ratio of silicon carbide, magnetic beads, percarboxylic acid ester and distearoyloxyisopropylaluminate is 0.3-0.8:1:0.3-0.5:0.5-1.

4. The compound fertilizer according to claim 1, characterized in that The mass ratio of vermiculite powder, seaweed fertilizer and humic acid in the carrier is 3-5:1:1-2.

5. The compound fertilizer according to claim 1, characterized in that In terms of mass proportions, the compound fertilizer comprises 10-20 parts of macroelements, 5-15 parts of medium and trace elements, 1-2 parts of composite microbial agents, 3-6 parts of carriers and 2-5 parts of controlled-release factors.

6. The compound fertilizer according to claim 1, characterized in that The magnetic beads are polystyrene magnetic beads.

7. The method for preparing compound fertilizer according to any one of claims 1 to 6, characterized in that: The preparation method comprises the following steps: fully and uniformly mixing macroelements, medium and trace elements, composite microbial agents, carriers and controlled release factors, adding mother liquor water to adjust the pH to neutral, and obtaining the product by extrusion granulation and sieving.

8. The preparation method according to claim 7, characterized in that: The mother liquid water is prepared from natural brassinolide and a crop root enhancement aid.

9. A fertilizer for promoting the growth of crops, characterized in that: The compound fertilizer comprises the compound fertilizer according to any one of claims 1 to 6.

10. Use of the compound fertilizer according to any one of claims 1 to 6 in promoting the growth of crops.