Multi-element synergistic water-soluble fertilizer and preparation method thereof

Abstract

The invention discloses a multi-element synergistic water-soluble fertilizer and a preparation method thereof in the technical field of water-soluble fertilizers. The multi-element synergistic water-soluble fertilizer is prepared from the following components in parts by weight: 40 to 50 parts of urea, 45 to 50 parts of monopotassium phosphate, 10 to 15 parts of potassium nitrate, 0.2 to 0.3 part of anhydrous magnesium sulfate, 0.1 to 0.2 part of zinc sulfate, 0.1 to 0.15 part of borax, 1 to 3 parts of functional agent and 0.4 to 0.5 part of anti-caking powder. The functional agent is added into the formula of the water-soluble fertilizer, the functional agent takes bacterial cellulose, dopamine hydrochloride and sodium alginate as carriers and loads the complex microbial inoculants, and the functional agent is used for promoting the absorption of the water-soluble fertilizer by leaf surfaces, improving the bioavailability of plants to the fertilizer and promoting the photosynthesis of the plants; therefore, the disease resistance and the plant fruit quality and yield are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of water-soluble fertilizers, and specifically refers to a multi-synergistic water-soluble fertilizer and a preparation method thereof. Background Art

[0002] Exogenous supplementation of trace elements is an important agronomic technology to maintain the normal growth of crops and improve the quality and yield of crops. As a product with quick effect, fast effect and long action period, macronutrient water-soluble fertilizer is widely used in the upstream and downstream industries of agricultural product production. Although trace elements such as zinc, boron and magnesium exist in small quantities in plants, they are components of enzymes or coenzymes in plants and have strong specificity. They play an important role in the growth and development of plants such as organ development, cell division and flower bud differentiation. Plants mainly absorb these trace elements from the soil to maintain the balance of trace elements in the body. When the trace elements in the soil are insufficient, plants will show symptoms of deficiency, such as smaller leaves when plants lack zinc; stunted growth and development when plants lack boron; and green leaves when plants lack boron. Through water-soluble fertilizers with different proportions of fully water-soluble macroelements (mainly zinc, boron and magnesium, with a total content ≥ 0.2), the trace elements necessary for crops in the growth and development process are supplemented, the normal growth of leaves is maintained, the synthesis of auxin and chlorophyll in plants is promoted, the rate of cell division and metabolism in plants is accelerated, the differentiation of plant flower buds is promoted, the stress resistance of plants is increased, the normal growth and development of plants is maintained, the quality and yield of crops are improved, and production and income for farmers are increased. Summary of the invention

[0003] In view of the above situation, in order to overcome the defects of the prior art, the present invention provides a multi-synergistic water-soluble fertilizer and a preparation method thereof. The present invention adds a functional agent to the water-soluble fertilizer formula. The functional agent is composed of bacterial cellulose, dopamine hydrochloride and sodium alginate as carriers, and a composite bacterial agent is loaded to promote the absorption of water-soluble fertilizer by the leaf surface, improve the bioavailability of fertilizer by plants, and promote photosynthesis of plants, thereby improving disease resistance and plant fruit quality and yield.

[0004] In order to achieve the above-mentioned object, the technical scheme adopted by the present invention is as follows: The present invention proposes a multi-synergistic water-soluble fertilizer, which comprises the following components in parts by weight: 40-50 parts of urea, 45-50 parts of potassium dihydrogen phosphate, 10-15 parts of potassium nitrate, 0.2-0.3 parts of anhydrous magnesium sulfate, 0.1-0.2 parts of zinc sulfate, 0.1-0.15 parts of borax, 1-3 parts of functional agent, and 0.4-0.5 parts of agglomerate powder;

[0005] Preferably, the settling powder includes at least one of talc, diatomaceous earth, calcium fluoride, sodium silicate, calcium silicate, bentonite, and polyvinyl alcohol;

[0006] Preferably, the raw materials for preparing the functional agent specifically include the following components in parts by weight: 1-1.2 parts of bacterial cellulose, 0.9-1 parts of dopamine hydrochloride, 0.25-0.35 parts of sodium alginate, and 0.5-0.6 parts of composite bacterial agent;

[0007] Preferably, the preparation method of the functional agent specifically comprises the following steps:

[0008] K1. Soak the bacterial cellulose in a 0.1 mol / L NaOH solution, raise the temperature to 70-80°C, react for 2-3 hours, wash with deionized water until neutral, place in a PBS buffer solution to break, centrifuge at 3000 rpm for 30 minutes, take the precipitate, freeze-dry, and obtain pretreated bacterial cellulose;

[0009] K2, dispersing the pretreated bacterial cellulose prepared in step K1 in an ethanol solution, adjusting the pH to 8-9, and after fully dissolving, stirring at 200 rpm for 1-2 hours, adding sodium chloroacetate and fully mixing, raising the temperature to 50-60° C., reacting for 6-7 hours, filtering, washing with deionized water until neutral, and freeze-drying to obtain carboxylated bacterial cellulose;

[0010] K3, dissolving the carboxylated bacterial cellulose prepared in step K2 in deionized water, adjusting the pH to 5 with 1 mol / L dilute hydrochloric acid, mixing well, placing in an ice water bath, adding EDC and NHS, stirring at 800-1000 rpm for 1-2 h under ice water bath conditions, adding dopamine hydrochloride, stirring and reacting for 1-2 h under nitrogen atmosphere, dialyzing with deionized water for 48 h, and freeze-drying to obtain DA / bacterial cellulose;

[0011] K4, dissolving sodium alginate in deionized water, adding the DA / bacterial cellulose prepared in step K5, stirring and reacting at a speed of 500-600 rpm for 1-2 hours to obtain a composite carrier solution, and sterilizing with ultraviolet light for later use;

[0012] K5. Activate Rhodopseudomonas palustris and Bacillus atrophaeus respectively to prepare a total viable bacterial count of 5×10 8 -5×10 9 The bacterial suspension of CFU / mL was centrifuged at a speed of 3000-5000rpm for 5-10min, the supernatant was removed, and the mixture was resuspended and washed with physiological saline, and then centrifuged to obtain a composite bacterial agent;

[0013] K6. Mix the composite bacterial agent prepared in step K5 with the composite carrier solution, mix at 100 rpm for 1 hour, and then transfer to the CaCl2 solution by dripping with a syringe. After forming microspheres, place them at 4°C, soak them in CaCl2 for 20-24 hours, filter, and freeze-dry to obtain a functional agent.

[0014] Preferably, in step K1, the mass fraction of the bacterial cellulose in the NaOH solution is 5-8%;

[0015] Preferably, in step K2, the mass concentration of the pretreated cellulose in the ethanol solution is 50-80 g / L;

[0016] Preferably, in step K2, the mass ratio of sodium chloroacetate to pretreated cellulose is 1:8-10;

[0017] Preferably, in step K3, the mass concentration of the carboxylated bacterial cellulose in deionized water is 30-40 g / L;

[0018] Preferably, in step K3, the amount of EDC added is 3%-5% of the mass of the carboxylated bacterial cellulose, and the amount of NHS added is 2%-4% of the mass of the carboxylated bacterial cellulose;

[0019] Preferably, in step K4, the mass fraction of sodium alginate in deionized water is 4%-8%;

[0020] Preferably, in step K5, the Rhodopseudomonas palustris is deposited in the China Industrial Microbiological Culture Collection Center with a deposit number of CICC 23812;

[0021] Preferably, in step K5, the Bacillus atrophaeu is deposited in the China Industrial Microbiological Culture Collection Center with a deposit number of CICC A0220;

[0022] Preferably, in step K5, the ratio of the live bacteria concentration between the Rhodopseudomonas palustris and the Bacillus atrophaeus is 2-3:1;

[0023] Preferably, in step K6, the mass fraction of the CaCl2 solution is 2%-3%;

[0024] The present invention also provides a method for preparing a multi-functional water-soluble fertilizer, which specifically comprises the following steps:

[0025] S1. Keep the temperature of urea, potassium dihydrogen phosphate, potassium nitrate, anhydrous magnesium sulfate, zinc sulfate and borax solution in deionized water at 30-40°C, stir at a speed of 1000-1200 pm until the solution is uniform, add functional agent and powder, continue stirring and mixing for 20-30 minutes, and obtain water-soluble fertilizer for standby use;

[0026] S2, filtering the water-soluble fertilizer in step S1 through a 100-200 mesh sieve until the mixed fertilizer solvent is clarified;

[0027] S3, adjusting the pH of the mixed fertilizer solution to 5.5-7 to obtain a water-soluble fertilizer;

[0028] Preferably, in step S1, the mass fraction of the water-soluble fertilizer is 0.1%-0.5%;

[0029] The beneficial effects achieved by the present invention are as follows:

[0030] The present invention provides a multi-functional synergistic water-soluble fertilizer and a preparation method thereof. The present invention adds a functional agent to the water-soluble fertilizer formula. The functional agent is composed of bacterial cellulose, dopamine hydrochloride and sodium alginate as carriers, and a composite bacterial agent is loaded to promote the absorption of the water-soluble fertilizer by the leaf surface, improve the bioavailability of the fertilizer by the plant, and promote the photosynthesis of the plant, thereby improving the disease resistance and the quality and yield of the plant fruit. The functional agent of the present invention uses bacterial cellulose and dopamine hydrochloride as a high-viscosity complex, cross-links carboxylated bacterial cellulose and dopamine hydrochloride through EDC and NHS, introduces catechol groups into the bacterial cellulose structure, improves the adhesion ability of the bacterial cellulose, and cross-links with sodium alginate to form a catechol group. The composite carrier formed by cross-linking has high hydrophilicity and can be evenly dispersed in water-soluble fertilizers. After spraying, the carrier can be fixed to the leaf surface by high adhesion. The composite bacterial agent of the present invention adopts photosynthetic bacteria, which can convert inorganic compounds or organic compounds other than H2O and H2S into nutrients that can be absorbed by plants. Photosynthetic bacteria can use many different substrates to provide a material basis for their metabolism. The extracellular products contain a large amount of plant growth-promoting and immune-inducing substances, such as indole-3-acetic acid, 5-aminolevulinic acid, iron carriers, riboflavin, acylhomoserine lactones and extracellular polysaccharides, which improve the stress resistance and disease resistance of plants, promote the absorption of effective ingredients by plants, and thus improve the quality and yield of plant fruits. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a SEM image of the functional agent prepared in this example;

[0032] Figure 2 This is an infrared spectrum image of the functional agent prepared in this example;

[0033] Figure 3 The biological shape result diagram of cabbage after spraying the water-soluble fertilizer prepared in Examples 1-3 and Comparative Examples 1-3;

[0034] Figure 4 This is a result diagram showing the effect of the water-soluble fertilizers prepared in Examples 1-3 and Comparative Examples 1-3 on the yield of Chinese cabbage.

[0035] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0037] Unless otherwise defined, all professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to those described herein may be applied to the present invention. The preferred implementation methods and materials described herein are for demonstration purposes only and are not intended to limit the content of this application.

[0038] The experimental methods in the following examples are conventional methods unless otherwise specified; the experimental materials and test strains used in the following examples are purchased from commercial channels unless otherwise specified.

[0039] Example 1

[0040] This embodiment provides a multi-functional water-soluble fertilizer, which includes the following components in parts by weight: 40 parts of urea, 50 parts of potassium dihydrogen phosphate, 10 parts of potassium nitrate, 0.3 parts of anhydrous magnesium sulfate, 0.2 parts of zinc sulfate, 0.1 parts of borax, 1 part of functional agent, and 0.4 parts of diatomaceous earth;

[0041] The raw materials for preparing the functional agent specifically include the following components in parts by weight: 1 part of bacterial cellulose, 0.9 part of dopamine hydrochloride, 0.25 part of sodium alginate, and 0.5 part of composite bacterial agent;

[0042] The preparation method of the functional agent specifically comprises the following steps:

[0043] K1, soak 5g bacterial cellulose in 100mL 0.1mol / LNaOH solution, raise the temperature to 80°C, react for 2h, wash with deionized water until neutral, place in 300mL PBS buffer solution to break, centrifuge at 3000rpm for 30min, take the precipitate, freeze-dry, and obtain pretreated bacterial cellulose;

[0044] K2, dispersing the pretreated bacterial cellulose prepared in step K1 in 100 mL of 85 vol% ethanol solution, adjusting the pH to 9, and after fully dissolving, stirring at 200 rpm for 2 hours, adding 0.5 g of sodium chloroacetate and fully mixing, raising the temperature to 60° C., reacting for 6 hours, filtering, washing with deionized water until neutral, and freeze-drying to obtain carboxylated bacterial cellulose;

[0045] K3, dissolving the carboxylated bacterial cellulose prepared in step K2 in 125 mL of deionized water, adjusting the pH to 5 with 1 mol / L dilute hydrochloric acid, mixing well, placing in an ice water bath, adding 0.15 g of EDC and 0.1 g of NHS, stirring at 800 rpm for 2 h in an ice water bath, adding 5 g of dopamine hydrochloride, stirring and reacting for 2 h under a nitrogen atmosphere, dialyzing with deionized water for 48 h, and freeze-drying to obtain DA / bacterial cellulose;

[0046] K4, dissolving 1.5 g of sodium alginate in 30 mL of deionized water, adding the DA / bacterial cellulose prepared in step K5, stirring and reacting at a speed of 600 rpm for 1 hour to obtain a composite carrier solution, and sterilizing with ultraviolet light for later use;

[0047] K5. Activate Rhodopseudomonas palustris and Bacillus atrophaeus respectively, and prepare a total live bacterial count of 5×10 8 The bacterial suspension of CFU / mL was centrifuged at 3000 rpm for 10 min, the supernatant was removed, and the mixture was resuspended and washed with physiological saline, and then centrifuged to obtain the composite bacterial agent;

[0048] K6. Mix the composite bacterial agent prepared in step K5 with the composite carrier solution, mix at 100 rpm for 1 hour, and then transfer to a 2 wt% CaCl2 solution by dripping with a syringe. After forming microspheres, place them at 4°C, soak them in CaCl2 for 20 hours, filter, and freeze-dry to obtain a functional agent.

[0049] Figure 1 This is the SEM image of the functional agent prepared in this example. Figure 2 This is an infrared spectrum image of the functional agent prepared in this example, indicating that this example successfully synthesized the functional agent.

[0050] The present invention also provides a method for preparing a multi-functional water-soluble fertilizer, which specifically comprises the following steps:

[0051] S1. Place urea, potassium dihydrogen phosphate, potassium nitrate, anhydrous magnesium sulfate, zinc sulfate and borax solution in 10.2L deionized water at 40°C, stir at 1000 pm until the solution is uniform, add functional agent and powder, continue stirring and mixing for 30 minutes to obtain water-soluble fertilizer for standby use. The mass fraction of the water-soluble fertilizer is 0.1%;

[0052] S2, filtering the water-soluble fertilizer in step S1 through a 200-mesh sieve until the mixed fertilizer solvent is clarified;

[0053] S3. Adjust the pH of the mixed fertilizer solution to 7 to obtain a water-soluble fertilizer.

[0054] Example 2

[0055] This embodiment provides a multi-functional water-soluble fertilizer, which includes the following components in parts by weight: 45 parts of urea, 45 parts of potassium dihydrogen phosphate, 12 parts of potassium nitrate, 0.25 parts of anhydrous magnesium sulfate, 0.1 parts of zinc sulfate, 0.15 parts of borax, 3 parts of functional agent, and 0.45 parts of calcium silicate;

[0056] The raw materials for preparing the functional agent specifically include the following components in parts by weight: 1.1 parts of bacterial cellulose, 1 part of dopamine hydrochloride, 0.3 parts of sodium alginate, and 0.6 parts of composite bacterial agent;

[0057] The preparation method of the functional agent specifically comprises the following steps:

[0058] K1, soak 7.5g bacterial cellulose in 100mL 0.1mol / LNaOH solution, raise the temperature to 70°C, react for 2.5h, wash with deionized water until neutral, place in 300mL PBS buffer solution to break, centrifuge at 3000rpm for 30min, take the precipitate, freeze-dry, and obtain pretreated bacterial cellulose;

[0059] K2, dispersing the pretreated bacterial cellulose prepared in step K1 in 100 mL of 85 vol% ethanol solution, adjusting the pH to 8, and fully dissolving, stirring at 200 rpm for 1.5 h, adding 0.8 g of sodium chloroacetate and fully mixing, raising the temperature to 50° C., reacting for 7 h, filtering, washing with deionized water until neutral, and freeze-drying to obtain carboxylated bacterial cellulose;

[0060] K3, dissolving the carboxylated bacterial cellulose prepared in step K2 in 250 mL of deionized water, adjusting the pH to 5 with 1 mol / L dilute hydrochloric acid, mixing well, placing in an ice water bath, adding 0.3 g of EDC and 0.3 g of NHS, stirring at 1000 rpm for 2 h in an ice water bath, adding 6.8 g of dopamine hydrochloride, stirring and reacting for 2 h under a nitrogen atmosphere, dialyzing with deionized water for 48 h, and freeze-drying to obtain DA / bacterial cellulose;

[0061] K4, dissolving 2 g of sodium alginate in 50 mL of deionized water, adding the DA / bacterial cellulose prepared in step K5, stirring and reacting at a speed of 500 rpm for 1 hour to obtain a composite carrier solution, and sterilizing with ultraviolet light for later use;

[0062] K5. Activate Rhodopseudomonas palustris and Bacillus atrophaeus respectively, and prepare a total live bacterial count of 1×10 9 The bacterial suspension of CFU / mL was centrifuged at 4000 rpm for 5 min, the supernatant was removed, and the mixture was resuspended and washed with physiological saline, and then centrifuged to obtain the composite bacterial agent;

[0063] K6, the composite bacterial agent prepared in step K5 is mixed with the composite carrier solution, mixed at 100 rpm for 1 hour, and then transferred to a 3wt% CaCl2 solution by dripping with a syringe, and after forming microspheres, placed at 4°C, soaked in CaCl2 for 24 hours, filtered, and freeze-dried to obtain a functional agent. The present invention also provides a method for preparing a multi-synergistic water-soluble fertilizer, which specifically comprises the following steps:

[0064] S1. Place urea, potassium dihydrogen phosphate, potassium nitrate, anhydrous magnesium sulfate, zinc sulfate and borax solution in 4.2L of deionized water at 30°C, stir at a speed of 1000 pm until the solution is uniform, add functional agent and powder, continue stirring and mixing for 30 minutes to obtain a water-soluble fertilizer for standby use. The mass fraction of the water-soluble fertilizer is 0.25%;

[0065] S2, filtering the water-soluble fertilizer in step S1 through a 200-mesh sieve until the mixed fertilizer solvent is clarified;

[0066] S3. Adjust the pH of the mixed fertilizer solution to 5.5 to obtain a water-soluble fertilizer.

[0067] Example 3

[0068] This embodiment provides a multi-functional synergistic water-soluble fertilizer, which includes the following components in parts by weight: 50 parts of urea, 45 parts of potassium dihydrogen phosphate, 15 parts of potassium nitrate, 0.2 parts of anhydrous magnesium sulfate, 0.1 parts of zinc sulfate, 0.1 parts of borax, 2 parts of functional agent, and 0.5 parts of bentonite;

[0069] The raw materials for preparing the functional agent specifically include the following components in parts by weight: 1.2 parts of bacterial cellulose, 1 part of dopamine hydrochloride, 0.35 parts of sodium alginate, and 0.55 parts of composite bacterial agent;

[0070] The preparation method of the functional agent specifically comprises the following steps:

[0071] K1, soak 8g of bacterial cellulose in 100mL of 0.1mol / LNaOH solution, raise the temperature to 75°C, react for 3h, wash with deionized water until neutral, place in 300mL of PBS buffer solution to break, centrifuge at 3000rpm for 30min, take the precipitate, freeze-dry, and obtain pretreated bacterial cellulose;

[0072] K2, dispersing the pretreated bacterial cellulose prepared in step K1 in 100 mL of 85 vol% ethanol solution, adjusting the pH to 8.5, and after fully dissolving, stirring at 200 rpm for 1 hour, adding 1 g of sodium chloroacetate and fully mixing, raising the temperature to 60° C., reacting for 7 hours, filtering, washing with deionized water until neutral, and freeze-drying to obtain carboxylated bacterial cellulose;

[0073] K3, dissolving the carboxylated bacterial cellulose prepared in step K2 in 200 mL of deionized water, adjusting the pH to 5 with 1 mol / L dilute hydrochloric acid, mixing well, placing in an ice water bath, adding 0.4 g of EDC and 0.24 g of NHS, stirring at 900 rpm for 2 h in an ice water bath, adding 6.7 g of dopamine hydrochloride, stirring and reacting for 2 h under a nitrogen atmosphere, dialyzing with deionized water for 48 h, and freeze-drying to obtain DA / bacterial cellulose;

[0074] K4, dissolving 2.4 g of sodium alginate in 40 mL of deionized water, adding the DA / bacterial cellulose prepared in step K5, stirring and reacting at a speed of 580 rpm for 1 hour to obtain a composite carrier solution, and sterilizing with ultraviolet light for later use;

[0075] K5. Activate Rhodopseudomonas palustris and Bacillus atrophaeus respectively, and prepare a total live bacterial count of 5×10 9 The bacterial suspension of CFU / mL was centrifuged at 5000 rpm for 8 min, the supernatant was removed, and the mixture was resuspended and washed with physiological saline, and then centrifuged to obtain the composite bacterial agent;

[0076] K6, the composite bacterial agent prepared in step K5 is mixed with the composite carrier solution, mixed at 100 rpm for 1 hour, and then transferred to a 2wt% CaCl2 solution by dripping with a syringe, and after forming microspheres, placed at 4°C, soaked in CaCl2 for 22 hours, filtered, and freeze-dried to obtain a functional agent. The present invention also provides a method for preparing a multi-synergistic water-soluble fertilizer, which specifically comprises the following steps:

[0077] S1. Place urea, potassium dihydrogen phosphate, potassium nitrate, anhydrous magnesium sulfate, zinc sulfate and borax solution in 2.3L deionized water at 40°C, stir at 1000 pm until the solution is uniform, add functional agent and powder, continue stirring and mixing for 30 minutes to obtain water-soluble fertilizer for standby use. The mass fraction of the water-soluble fertilizer is 0.5%;

[0078] S2, filtering the water-soluble fertilizer in step S1 through a 100-mesh sieve until the mixed fertilizer solvent is clarified;

[0079] S3. Adjust the pH of the mixed fertilizer solution to 6 to obtain a water-soluble fertilizer.

[0080] Comparative Example 1

[0081] This comparative example provides a water-soluble fertilizer and a preparation method thereof, which differs from Example 1 only in that no functional agent is included in all components, and the remaining components and component contents are the same as those in Example 1.

[0082] Comparative Example 2

[0083] This comparative example provides a water-soluble fertilizer and a preparation method thereof, which is different from Example 1 only in that dopamine hydrochloride is not included in the functional agent, and the remaining components and component contents are the same as those in Example 1.

[0084] Comparative Example 3

[0085] This comparative example provides a water-soluble fertilizer and a preparation method thereof, which is different from Example 1 only in that the functional agent does not include a composite bacterial agent, and the remaining components and component contents are the same as those in Example 1.

[0086] Experimental Example 1: Field Test

[0087] Trial period: June 2023 to December 2023;

[0088] Test crops: Chinese cabbage (Mayeqing), cultivated in the open field;

[0089] Climate conditions during the test: The test is located at 30°04~'33.65"N, 103°50~'54.46"E, 391.4 meters above sea level. The Dongpo area belongs to the subtropical humid climate zone, with no severe cold in winter, no extreme heat in summer, rare frost and snow, distinct four seasons, abundant rainfall, and rich light and temperature resources. The annual average temperature is 17.2℃, the frost-free period is 318 days, the annual average rainfall is 1057.5 mm, and the annual average sunshine hours are 1193.8 hours. The water resources are abundant, with an annual average runoff of 543 million cubic meters and a total water volume of 1.503 billion cubic meters;

[0090] Experimental design: A completely randomized block design was used, with 7 treatments (including blank, which was water), 3 repetitions, and a total of 12 plots with an area of ​​30m2. Each plot in the same plot was planted for 3 consecutive crops. The experiment set up protected rows.

[0091] Figure 3 The results of the biological morphology of cabbage after spraying the water-soluble fertilizers prepared in Examples 1-3 and Comparative Examples 1-3 are shown. As shown in the figure, the water-soluble fertilizers prepared in Examples 1-3 have a greater effect on the biological morphology of cabbage. The present invention improves the functional agent by using bacterial cellulose, dopamine hydrochloride and sodium alginate as carriers to load the composite bacterial agent to promote the absorption of water-soluble fertilizers by the leaves, improve the bioavailability of fertilizers by plants, promote photosynthesis of plants, and promote plant growth.

[0092] Figure 4 The results of the influence of the water-soluble fertilizers prepared in Examples 1-3 and Comparative Examples 1-3 on the yield of cabbage are shown in the figure. As shown in the figure, the water-soluble fertilizers prepared in Examples 1-3 can promote the yield of cabbage, and its yield can reach 4200kg / mu. The above data show that the water-soluble fertilizers prepared in the present invention can promote the growth of cabbage and increase the yield.

[0093] While the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that many changes, modifications, substitutions and variations can be made to the embodiments without departing from the principles and spirit of the invention.

[0094] The present invention and its implementation methods are described above, which is not restrictive. The drawings are only one of the implementation methods of the present invention, and the actual application is not limited thereto. In short, if ordinary technicians in the field are inspired by it and design methods and embodiments similar to the technical solution without creativity without departing from the purpose of the invention, they should all fall within the protection scope of the present invention.

Claims

1. A multi-functional water-soluble fertilizer, characterized in that: The water-soluble fertilizer comprises the following components in parts by weight: 40-50 parts of urea, 45-50 parts of potassium dihydrogen phosphate, 10-15 parts of potassium nitrate, 0.2-0.3 parts of anhydrous magnesium sulfate, 0.1-0.2 parts of zinc sulfate, 0.1-0.15 parts of borax, 1-3 parts of functional agent, and 0.4-0.5 parts of setting powder; the raw materials for preparing the functional agent specifically comprise the following components in parts by weight: 1-1.2 parts of bacterial cellulose, 0.9-1 parts of dopamine hydrochloride, 0.25-0.35 parts of sodium alginate, and 0.5-0.6 parts of composite bacterial agent.

2. The multi-synergistic water-soluble fertilizer according to claim 1, characterized in that: The settling powder includes at least one of talcum powder, diatomaceous earth, calcium fluoride, sodium silicate, calcium silicate, bentonite and polyvinyl alcohol.

3. A method for preparing the multi-synergistic water-soluble fertilizer according to claim 1 or 2, characterized in that: The specific steps include: S1. Keep the temperature of urea, potassium dihydrogen phosphate, potassium nitrate, anhydrous magnesium sulfate, zinc sulfate and borax solution in deionized water at 30-40°C, stir at a speed of 1000-1200 pm until the solution is uniform, add functional agent and powder, continue stirring and mixing for 20-30 minutes, and obtain water-soluble fertilizer for standby use; the mass fraction of the water-soluble fertilizer is 0.1%-0.5%; S2, filtering the water-soluble fertilizer in step S1 through a 100-200 mesh sieve until the mixed fertilizer solvent is clarified; S3. Adjust the pH of the mixed fertilizer solution to 5.5-7 to obtain a water-soluble fertilizer;.

4. The method for preparing a multi-synergistic water-soluble fertilizer according to claim 3, characterized in that: The preparation method of the functional agent specifically comprises the following steps: K1. Soak the bacterial cellulose in a 0.1 mol / L NaOH solution, raise the temperature to 70-80°C, react for 2-3 hours, wash with deionized water until neutral, place in a PBS buffer solution to break, centrifuge at 3000 rpm for 30 minutes, take the precipitate, freeze-dry, and obtain pretreated bacterial cellulose; K2, dispersing the pretreated bacterial cellulose prepared in step K1 in an ethanol solution, adjusting the pH to 8-9, and after fully dissolving, stirring at 200 rpm for 1-2 hours, adding sodium chloroacetate and fully mixing, raising the temperature to 50-60° C., reacting for 6-7 hours, filtering, washing with deionized water until neutral, and freeze-drying to obtain carboxylated bacterial cellulose; K3, dissolving the carboxylated bacterial cellulose prepared in step K2 in deionized water, adjusting the pH to 5 with 1 mol / L dilute hydrochloric acid, mixing well, placing in an ice water bath, adding EDC and NHS, stirring at 800-1000 rpm for 1-2 h under ice water bath conditions, adding dopamine hydrochloride, stirring and reacting for 1-2 h under nitrogen atmosphere, dialyzing with deionized water for 48 h, and freeze-drying to obtain DA / bacterial cellulose; K4, dissolving sodium alginate in deionized water, adding the DA / bacterial cellulose prepared in step K5, stirring and reacting at a speed of 500-600 rpm for 1-2 hours to obtain a composite carrier solution, and sterilizing with ultraviolet light for later use; K5. Activate Rhodopseudomonas palustris and Bacillus atrophaeus respectively to prepare a total viable bacterial count of 5×10 8 -5×10 9 The bacterial suspension of CFU / mL was centrifuged at a speed of 3000-5000rpm for 5-10min, the supernatant was removed, and the mixture was resuspended and washed with physiological saline, and then centrifuged to obtain a composite bacterial agent; K6. Mix the composite bacterial agent prepared in step K5 with the composite carrier solution, mix at 100 rpm for 1 hour, and then transfer to the CaCl2 solution by dripping with a syringe. After forming microspheres, place them at 4°C, soak them in CaCl2 for 20-24 hours, filter, and freeze-dry to obtain the functional agent.

5. The method for preparing a multi-functional water-soluble fertilizer according to claim 4, characterized in that: In step K1, the mass fraction of the bacterial cellulose in the NaOH solution is 5-8%.

6. The method for preparing a multi-synergistic water-soluble fertilizer according to claim 5, characterized in that: In step K2, the mass concentration of the pretreated cellulose in the ethanol solution is 50-80 g / L; the mass ratio of the sodium chloroacetate to the pretreated cellulose is 1:8-10.

7. The method for preparing a multi-synergistic water-soluble fertilizer according to claim 6, characterized in that: In step K3, the mass concentration of the carboxylated bacterial cellulose in deionized water is 30-40 g / L; the amount of EDC added is 3%-5% of the mass of the carboxylated bacterial cellulose, and the amount of NHS added is 2%-4% of the mass of the carboxylated bacterial cellulose.

8. The method for preparing a multi-functional water-soluble fertilizer according to claim 7, characterized in that: In step K4, the mass fraction of sodium alginate in deionized water is 4%-8%.

9. The method for preparing a multi-functional water-soluble fertilizer according to claim 8, characterized in that: In step K5, the Rhodopseudomonas palustris is deposited in the China Industrial Microbiological Culture Collection Center with a deposit number of CICC 23812; the Bacillus atrophaeu is deposited in the China Industrial Microbiological Culture Collection Center with a deposit number of CICC A0220; the live bacteria concentration ratio between the Rhodopseudomonas palustris and the Bacillus atrophaeu is 2-3:

1.

10. The method for preparing a multi-functional water-soluble fertilizer according to claim 9, characterized in that: In step K6, the mass fraction of the CaCl2 solution is 2%-3%.

Images