Special fertilizer for disease-resistant crops and preparation method thereof

Abstract

The present application relates to the field of fertilizer, in particular to a kind of special fertilizer for crop of disease resistance and preparation method thereof, special fertilizer includes nutrient core, microbial inoculant coating, trace element coating from inside to outside;Nutrient core includes nitrogen fertilizer 35-40 parts, phosphorus fertilizer 20-25 parts, potassium fertilizer 15-20 parts, synergist 3-5 parts, molasses 1-1.5 parts by weight;Microbial inoculant coating layer includes liquid microbial inoculant 1-2 parts, microbial protective agent 1-2 parts, microbial inoculant carrier 3-5 parts;Trace element coating layer includes trace element fertilizer 5-10 parts, and wrapping agent 0.8-1.6 parts.The special fertilizer for crop of disease resistance provided in the present application adds trace element by outer wrapping mode, avoids the chemical reaction of metal cation in trace element and phosphate ion in phosphorus fertilizer in the process of fertilizer production, reduces the effectiveness of nutrient composition.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of fertilizers, in particular to a disease-resistant crop special fertilizer and a preparation method thereof. BACKGROUND

[0002] Diseases caused by pathogenic microorganisms such as bacteria, fungi and pests seriously affect the yield and quality of crops. According to statistics, the grain yield caused by pathogenic microorganisms is more than 20% per year, which poses a great threat to food security. At present, the main way to prevent and control pathogenic microorganisms is to use chemical pesticides. However, long-term use of chemical pesticides not only increases the resistance of pathogenic microorganisms and reduces the efficacy, but also causes environmental pollution and other problems.

[0003] Microbial inoculants are green and environmentally friendly, low in cost, can improve soil and improve the microenvironment of crop roots, and improve the disease resistance of crops, and are widely used in modern agricultural production. In planting, microbial inoculants are often used in combination with fertilizers, but this will increase labor costs, so it is of great significance to develop a compound product of fertilizer and microbial inoculant. However, the production process of fertilizers such as high-tower granulation and spray granulation is often accompanied by high temperature, which can easily cause the number of active bacteria to decrease and affect the final application effect.

[0004] High-intensity planting activities can take away a large amount of nutrients from the soil, among which nitrogen, phosphorus and potassium macronutrients can be supplemented by fertilization, while the application of micronutrient fertilizers is generally insufficient. Micronutrient fertilizers can improve crop quality, improve crop disease resistance, and also improve soil structure. The lack of micronutrients not only causes crops to have "deficiency symptoms", but also affects the absorption of plants to macronutrients, causing low fertilizer utilization. At present, fertilizer enterprises add micronutrients to traditional compound fertilizers to produce new fertilizers, but the micronutrients are mainly divalent metal ions, and active ions such as phosphate in phosphate fertilizer can easily react with divalent cations under certain conditions to form precipitates, thereby affecting the field application effect of micronutrients. Therefore, it is urgent to develop a compound fertilizer and a production method that can efficiently utilize micronutrients. SUMMARY

[0005] In view of the problems in the prior art, the purpose of the present application is to provide a disease-resistant crop special fertilizer and a preparation method thereof.

[0006] The purpose of the present application is achieved by the following technical solutions:

[0007] In a first aspect, the present application provides a disease-resistant crop special fertilizer, the fertilizer is granular, including a nutrient core, a microbial agent coating layer and a medium trace element coating layer from inside to outside; the nutrient core includes, by weight, 35-40 parts of nitrogen fertilizer, 20-25 parts of phosphorus fertilizer, 15-20 parts of potassium fertilizer, 3-5 parts of synergist and 1-1.5 parts of molasses; the microbial agent coating layer includes 1-2 parts of liquid microbial agent, 1-2 parts of microbial protection agent and 3-5 parts of microbial agent carrier; the medium trace element coating layer includes 5-10 parts of medium trace element fertilizer and 0.8-1.6 parts of wrapping agent.

[0008] Preferably, the nitrogen fertilizer is one or more of urea, ammonium bicarbonate, ammonium sulfate, ammonium chloride, sodium nitrate, calcium nitrate and ammonium nitrate.

[0009] Preferably, the phosphorus fertilizer is one or more of monoammonium phosphate, diammonium phosphate, ammonium phosphate, ammonium polyphosphate, superphosphate, triple superphosphate, calcium magnesium phosphate and phosphate rock.

[0010] Preferably, the potassium fertilizer is one or more of potassium chloride and potassium sulfate.

[0011] Preferably, the synergist is one or more of humic acid, alginic acid, chitosan and amino acid.

[0012] Preferably, the medium trace element fertilizer is one or more of compounds of calcium, magnesium, iron, copper, zinc, manganese and molybdenum.

[0013] Preferably, the liquid microbial agent is composed of Bacillus subtilis, Bacillus mycoides and Pseudomonas fluorescens, wherein the effective viable count of Bacillus subtilis is not less than 200 million / mL, the effective viable count of Bacillus mycoides is not less than 200 million / mL and the effective viable count of Pseudomonas fluorescens is not less than 500 million / mL.

[0014] Preferably, the microbial protection agent is a mixture of brown algal oligosaccharide and rhamnolipid.

[0015] Preferably, the mass ratio of brown algal oligosaccharide to rhamnolipid in the microbial protection agent is 1:(1-1.5).

[0016] Preferably, the average degree of polymerization of brown algal oligosaccharide in the microbial protection agent is not higher than 5.

[0017] Preferably, the preparation method of the microbial agent carrier comprises:

[0018] S1, aging treatment:

[0019] After diatomite is ground and passed through a 150-180 mesh sieve, 1 mol / L sulfuric acid solution is added, stirring is performed for 1.5-2 h, then water washing is performed until the filtrate is neutral, and then drying is performed at 105°C to obtain the aged diatomite.

[0020] S2, introducing metal ions:

[0021] Manganese sulfate and ferric sulfate were added to deionized water to form a sulfate solution; after aging, diatomite was added and mixed thoroughly to obtain a diatomite mixture;

[0022] S3, modification treatment:

[0023] Humic acid (50kDa-100kDa) was added to a sodium hydroxide solution with pH = 8-9, and stirred until fully dissolved to obtain a humic acid solution; the humic acid solution was added dropwise to the diatomite mixture, and stirred constantly during the dropwise addition; after the dropwise addition was completed, the pH of the system was adjusted to 4-6, and the system was allowed to stand for 10-20h; after drying under reduced pressure, the product was washed with distilled water 3-5 times, and dried at 105℃ to obtain a microbial inoculant carrier.

[0024] Preferably, in S1, the mass-volume ratio of diatomite and sulfuric acid solution is 1g:(10-20)mL.

[0025] Preferably, in S2, the mass-volume ratio of aged diatomite, manganese sulfate, ferric sulfate, and deionized water is 1g:(0.13-0.18)g:(0.2-0.4)g:(10-20)mL.

[0026] Preferably, in S3, the mass-volume ratio of humic acid and sodium hydroxide solution is 1g:(5-10)mL; the volume ratio of humic acid solution and diatomite mixture is 1:3-6.

[0027] Preferably, the coating agent is modified gum arabic, and the preparation method comprises:

[0028] S10, preparation of phosphorylated chitosan:

[0029] Chitosan was weighed and dissolved in an acetic acid solution, and a phosphoric acid solution was added dropwise; the temperature was raised to 50-60℃, and stirring was performed for 10-15h; after the treatment was completed, the product was poured into ethanol, the precipitate was collected, washed with ethanol 3 times, and dried at 60℃ to obtain phosphorylated chitosan;

[0030] S11, preparation of raw materials:

[0031] Phosphorylated chitosan was dissolved in distilled water to prepare a phosphorylated chitosan solution; gum arabic was first dissolved in a sodium hydroxide solution, and the solution was heated to 50℃; then the solution was diluted with distilled water to prepare a gum arabic solution;

[0032] S12, preparation of modified gum arabic:

[0033] The phosphated chitosan solution is slowly added into the gum arabic solution, stirred at 600 rpm for 2-4 h at 50-60℃, then the pH of the system is adjusted to 5-6, and the modified gum arabic is obtained after filtration, washing with distilled water for 3-5 times, and drying at 60℃.

[0034] Preferably, in S10, the mass fraction of the acetic acid solution is 2%-4%, and the mass-volume ratio of chitosan and the acetic acid solution is 1 g:(10-20) mL.

[0035] Preferably, in S10, the mass fraction of the phosphoric acid solution is 80%-85%, and the addition amount of the phosphoric acid solution is 1:4-6 of the volume of the acetic acid solution.

[0036] Preferably, in S11, the mass fraction of phosphated chitosan in the phosphated chitosan solution is 1-3%, the mass fraction of sodium hydroxide solution is 0.5-2.5%, and the mass fraction of gum arabic in the gum arabic solution is 2-4%.

[0037] Preferably, in S12, the volume ratio of the phosphated chitosan solution to the gum arabic solution is 1:2-3.

[0038] In a second aspect, the present application provides a preparation method of a disease-resistant crop special fertilizer, comprising the following steps:

[0039] Step 1, preparing nutrient core: according to the weight ratio, nitrogen fertilizer, phosphorus fertilizer, potassium fertilizer and synergist are weighed and mixed uniformly, then granulated to prepare fertilizer particles, the fertilizer particles are placed in a constant temperature oven at 40-42℃ for 2 h, then a coating device is added, and molasses is sprayed to cover the surface of the nutrient core to prepare the nutrient core;

[0040] Step 2, coating microbial inoculant film: the microbial protective agent and the microbial inoculant carrier are added into the liquid microbial inoculant, and fully shaken for 10-15 min, then the solid is collected by filtration and freeze-dried to prepare the microbial inoculant film material, which is then sprayed to cover the surface of the nutrient core to prepare the nutrient core coated with the microbial inoculant film;

[0041] Step 3, coating medium trace element film: the nutrient core coated with the microbial inoculant film is heated to 40-42℃, the coating agent is sprayed to cover the nutrient core coated with the microbial inoculant film, and then the medium trace element fertilizer is further sprayed on the surface, and the disease-resistant crop special fertilizer is prepared after cooling and drying.

[0042] Preferably, in Step 1, the diameter of the nutrient core is 2.6-2.8 mm; in Step 2, the diameter of the nutrient core coated with the microbial inoculant film is 3.0-3.2 mm; and in Step 3, the diameter of the disease-resistant crop special fertilizer is 3.5-3.7 mm.

[0043] The present application has the following advantages:

[0044] 1. The anti-disease crop special fertilizer provided by the present application has a multi-layer coating structure, the innermost nutrient core can slowly release macronutrients and synergists to the soil through the microbial agent coating layer and the medium and trace element coating layer, meeting the demand of crop growth period for macronutrients; the microbial agent coating layer contains beneficial microorganisms that can improve soil physical and chemical properties, improve the rhizosphere microenvironment of crops, and improve the stress resistance of crops, which can effectively improve the resistance of crops to adverse environments and improve crop quality; the medium and trace element coating layer can effectively supplement the lack of medium and trace elements in the soil, further improving the yield and quality of crops.

[0045] 2. The anti-disease crop special fertilizer provided by the present application, the microbial agent coating layer includes a microbial protective agent and a microbial agent carrier, the microbial protective agent is composed of brown algal oligosaccharide and rhamnolipid, which can effectively reduce the problem of reduced microbial activity caused by adverse environmental factors such as high temperature during fertilizer production, and the microbial agent carrier introduces humic acid and manganese-iron complex on the basis of diatomite, which not only has rich micropores and adsorption, but also can provide a microenvironment for efficient reproduction of microorganisms, reducing the influence of adverse environmental factors on microbial activity.

[0046] 3. The anti-disease crop special fertilizer provided by the present application adds medium and trace elements by external coating, avoiding the chemical reaction between the metal cations of medium and trace elements and the phosphate ions in phosphate fertilizer during fertilizer production, which reduces the effectiveness of nutrient components.

[0047] 4. The anti-disease crop special fertilizer provided by the present application, the coating agent in the medium and trace element coating layer is modified gum arabic, which is obtained by phosphatizing chitosan and gum arabic after phosphatization reaction. The modified gum arabic has stronger adsorption to medium and trace element fertilizer, which not only can gradually supply nutrients during crop growth, improving the nutrient utilization rate of crops, but also can further protect the microbial agent, avoiding the influence of fertilizer storage and transportation on microbial activity. DETAILED DESCRIPTION

[0048] The technical solutions of the present application are described below through specific examples. It should be understood that the one or more method steps mentioned in the present application do not exclude other method steps before and after the combination steps or other method steps inserted between the explicitly mentioned steps; it should also be understood that the examples are only used to illustrate the present application and not to limit the scope of the present application. Moreover, unless otherwise specified, the numbering of the method steps is only a convenient tool to identify the method steps and not a limitation on the arrangement order of the method steps or a limitation on the scope of the present application, and the change or adjustment of the relative relationship without substantial change of the technical content is also considered as the scope of the present application.

[0049] In order to better understand the above technical solutions, the exemplary embodiments of the present application are described in more detail below. Although exemplary embodiments of the present application are shown, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present application and to fully convey the scope of the present application to those skilled in the art.

[0050] The present application is further described below in conjunction with the following examples.

[0051] Example 1

[0052] A disease-resistant crop-specific fertilizer, the fertilizer is in granular form, including from inside to outside a nutrient core, a microbial agent coating, and a medium and trace element coating; the nutrient core includes, by weight, urea 37 parts, monoammonium phosphate 22 parts, potassium chloride 18 parts, humic acid 4 parts, and molasses 1 part; the microbial agent coating layer includes liquid microbial agent 1.5 parts, microbial protection agent 1.5 parts, and microbial agent carrier 4 parts; the medium and trace element coating layer includes medium and trace element fertilizer 7 parts and coating agent 1.2 parts.

[0053] The liquid microbial agent is composed of Bacillus subtilis, Bacillus mycoides, and Pseudomonas fluorescens, the effective viable count of Bacillus subtilis is not less than 200 million / mL, the effective viable count of Bacillus mycoides is not less than 200 million / mL, and the effective viable count of Pseudomonas fluorescens is not less than 500 million / mL.

[0054] The microbial protection agent is a mixture of brown algal oligosaccharide (average degree of polymerization 4) and rhamnolipid at a mass ratio of 1:1.

[0055] The preparation method of the microbial agent carrier includes:

[0056] S1, 1g of diatomite is ground and passed through a 160-mesh sieve, then added to 15mL of 1mol / L sulfuric acid solution, stirred for 2h, then washed with water until the filtrate is neutral, and then dried at 105℃ to obtain aged diatomite;

[0057] S2. Add 0.15g of manganese sulfate and 0.3g of ferric sulfate to 15mL of deionized water to form a sulfate solution; add 1g of aged diatomaceous earth and mix thoroughly until homogeneous to obtain a diatomaceous earth mixture.

[0058] S3. Add 1g of humic acid (80kDa) to 8mL of sodium hydroxide solution with pH=8-9 and stir until fully dissolved to obtain a humic acid solution. Add the humic acid solution dropwise to the diatomaceous earth mixture at a volume ratio of 1:4, stirring continuously during the addition. After the addition is complete, adjust the pH of the system to 4-6, let it stand for 15h, dry under reduced pressure, wash three times with distilled water, and dry at 105℃ to obtain the microbial inoculant carrier.

[0059] The micronutrient fertilizer is composed of magnesium sulfate, diammonium humate ferric sulfate, copper sulfate monohydrate, zinc sulfate monohydrate, manganese sulfate, and sodium molybdate in a mass ratio of 1:1:1:1:1:1.

[0060] The encapsulating agent is modified gum arabic, and the preparation method includes:

[0061] S10. Weigh 1g of chitosan and dissolve it in 15mL of 4wt% acetic acid solution. Add 85wt% phosphoric acid solution dropwise, with the addition volume being 1:5 of the volume of the acetic acid solution. Heat to 50-60℃ and stir for 12h. After the treatment is completed, pour it into 2 times the volume of ethanol, collect the precipitate, wash it 3 times with ethanol, and dry it at 60℃ to obtain phosphorylated chitosan.

[0062] S11. Dissolve phosphorylated chitosan in distilled water to prepare a 2% phosphorylated chitosan solution; dissolve gum arabic in a 1.5% sodium hydroxide solution, heat the solution to 50°C, and then dilute with distilled water to prepare a 3% gum arabic solution.

[0063] S12. The phosphorylated chitosan solution is slowly added to the gum arabic solution, with a volume ratio of gum arabic solution to phosphorylated chitosan solution of 2.5:1. The mixture is stirred at 55°C and 600 rpm for 3 hours. The pH of the system is then adjusted to 5-6. After filtration, the mixture is washed three times with distilled water and dried at 60°C to obtain the modified gum arabic.

[0064] The preparation method of the above-mentioned disease-resistant crop-specific fertilizer includes the following steps:

[0065] Step 1: Preparation of nutrient core: Weigh nitrogen fertilizer, phosphorus fertilizer, potassium fertilizer and synergist according to the weight ratio, mix evenly and granulate to make fertilizer granules. Place the fertilizer granules at 42℃ for constant temperature drying for 2 hours, then add a coating device and spray molasses to cover the surface of the nutrient core to obtain a nutrient core with a diameter of 2.8mm.

[0066] Step 2, covering the microbial inoculant film: add the microbial protective agent and the microbial inoculant carrier into the liquid microbial inoculant, fully shake for 15 min, collect the solid by filtration, and freeze-dry to obtain the microbial inoculant film material. Then, spray the microbial inoculant film material on the surface of the nutrient core to obtain the nutrient core coated with the microbial inoculant film, with a diameter of 3.2 mm.

[0067] Step 3, covering the medium trace element film: heat the nutrient core coated with the microbial inoculant film to 42℃, spray the coating agent on the nutrient core coated with the microbial inoculant film, and then further spray the medium trace element fertilizer on the surface. After cooling and drying, the disease-resistant special fertilizer for crops is obtained, with a diameter of 3.7 mm.

[0068] Example 2

[0069] A disease-resistant special fertilizer for crops, which is in the form of granules and comprises, from inside to outside, a nutrient core, a microbial inoculant film, and a medium trace element film. The nutrient core comprises, by weight, 40 parts of ammonium chloride, 20 parts of diammonium phosphate, 18 parts of potassium sulfate, 4 parts of alginic acid, and 1.5 parts of molasses. The microbial inoculant film comprises 1 part of liquid microbial inoculant, 1 part of microbial protective agent, and 3 parts of microbial inoculant carrier. The medium trace element film comprises 5 parts of medium trace element fertilizer and 0.8 parts of coating agent.

[0070] The liquid microbial inoculant is composed of Bacillus subtilis, Bacillus mycoides, and Pseudomonas fluorescens. The effective viable count of Bacillus subtilis is not less than 200 million / mL, the effective viable count of Bacillus mycoides is not less than 200 million / mL, and the effective viable count of Pseudomonas fluorescens is not less than 500 million / mL.

[0071] The microbial protective agent is a mixture of brown algal oligosaccharide (with an average degree of polymerization of 4.5) and rhamnolipid at a mass ratio of 1:1.

[0072] The preparation method of the microbial inoculant carrier comprises:

[0073] S1, grind 1 g of diatomite and pass it through a 150-mesh sieve, then add 10 mL of 1 mol / L sulfuric acid solution, stir for 1.5 h, then wash with water until the filtrate is neutral, and then dry at 105℃ to obtain aged diatomite;

[0074] S2, add 0.13 g of manganese sulfate and 0.2 g of ferric sulfate to 10 mL of deionized water to form a sulfate solution; add 1 g of aged diatomite, mix thoroughly until uniform, and then obtain a diatomite mixture;

[0075] S3. Add 1g of humic acid (50kDa) to 5mL of sodium hydroxide solution with pH=8-9 and stir until fully dissolved to obtain a humic acid solution. Add the humic acid solution dropwise to the diatomaceous earth mixture at a volume ratio of 1:3, stirring continuously during the addition. After the addition is complete, adjust the pH of the system to 4-6, let it stand for 10 hours, dry under reduced pressure, wash three times with distilled water, and dry at 105℃ to obtain the microbial inoculant carrier.

[0076] The micronutrient fertilizer is composed of magnesium sulfate, diammonium humate ferric sulfate, copper sulfate monohydrate, zinc sulfate monohydrate, manganese sulfate, and sodium molybdate in a mass ratio of 1:1:1:1:1:1.

[0077] The encapsulating agent is modified gum arabic, and the preparation method includes:

[0078] S10. Weigh 1g of chitosan and dissolve it in 10mL of 2wt% acetic acid solution. Add 80wt% phosphoric acid solution dropwise, with the addition volume being 1:4 of the volume of the acetic acid solution. Heat to 50℃ and stir for 10h. After the treatment is completed, pour it into 2 times the volume of ethanol, collect the precipitate, wash it 3 times with ethanol, and dry it at 60℃ to obtain phosphorylated chitosan.

[0079] S11. Dissolve phosphorylated chitosan in distilled water to prepare a 1% (w / w) phosphorylated chitosan solution; dissolve gum arabic in a 0.5% (w / w) sodium hydroxide solution, heat the solution to 50°C, and then dilute with distilled water to prepare a 2-4% (w / w) gum arabic solution.

[0080] S12. The phosphorylated chitosan solution is slowly added to the gum arabic solution, with a volume ratio of gum arabic solution to phosphorylated chitosan solution of 2:1. The mixture is stirred at 50°C and 600 rpm for 2 hours. The pH of the system is then adjusted to 5-6. After filtration, the mixture is washed three times with distilled water and dried at 60°C to obtain the modified gum arabic.

[0081] The preparation method of the above-mentioned disease-resistant crop-specific fertilizer includes the following steps:

[0082] Step 1: Preparation of nutrient core: Weigh nitrogen fertilizer, phosphorus fertilizer, potassium fertilizer and synergist according to the weight ratio, mix evenly and granulate to make fertilizer granules. Place the fertilizer granules at 40℃ for constant temperature drying for 2 hours, then add a coating device and spray molasses to cover the surface of the nutrient core to obtain a nutrient core with a diameter of 2.6 mm.

[0083] Step 2, covering the microbial inoculant film: the microbial protective agent, the microbial inoculant carrier are added into the liquid microbial inoculant, and the mixture is shaken for 10 minutes to contact each other, and then the solid is collected by filtration and freeze-dried to obtain the microbial inoculant film material. Then, the microbial inoculant film material is sprayed on the surface of the nutrient core to obtain the nutrient core coated with the microbial inoculant film, and the diameter of the nutrient core is 3.0 mm.

[0084] Step 3, covering the medium trace element film: the nutrient core coated with the microbial inoculant film is heated to 40℃, and the coating agent is sprayed on the nutrient core coated with the microbial inoculant film, and then the medium trace element fertilizer is further sprayed on the surface. After cooling and drying, the disease-resistant special fertilizer for crops is obtained, and the diameter of the disease-resistant special fertilizer for crops is 3.5 mm.

[0085] Example 3

[0086] A disease-resistant special fertilizer for crops, the fertilizer is in a granular form, and includes a nutrient core, a microbial inoculant film and a medium trace element film from inside to outside. The nutrient core includes 35 parts of ammonium nitrate, 25 parts of calcium superphosphate, 15 parts of potassium sulfate, 4 parts of chitosan and 1.5 parts of molasses by weight. The microbial inoculant film includes 2 parts of liquid microbial inoculant, 2 parts of microbial protective agent and 5 parts of microbial inoculant carrier. The medium trace element film includes 10 parts of medium trace element fertilizer and 1.6 parts of coating agent.

[0087] The liquid microbial inoculant is composed of Bacillus subtilis, Bacillus mycoides and Pseudomonas fluorescens. The effective viable count of Bacillus subtilis is not less than 200 million / mL, the effective viable count of Bacillus mycoides is not less than 200 million / mL, and the effective viable count of Pseudomonas fluorescens is not less than 500 million / mL.

[0088] The microbial protective agent is a mixture of brown algal oligosaccharide (average degree of polymerization is 5) and rhamnolipid at a mass ratio of 1:1.

[0089] The preparation method of the microbial inoculant carrier includes:

[0090] S1, 1g of diatomite is ground and passed through a 180-mesh sieve, and then added into 20mL of 1mol / L sulfuric acid solution, and stirred for 2h. Then, the diatomite is washed with water until the filtrate is neutral, and then dried at 105℃ to obtain aged diatomite.

[0091] S2, 0.18g of manganese sulfate and 0.4g of ferric sulfate are added into 20mL of deionized water to form a sulfate solution. Then, 1g of the aged diatomite is added and mixed uniformly to obtain a diatomite mixture.

[0092] S3. Add 1g of humic acid (100kDa) to 10mL of sodium hydroxide solution with pH=8-9 and stir until fully dissolved to obtain a humic acid solution. Add the humic acid solution dropwise to the diatomaceous earth mixture at a volume ratio of 1:6, stirring continuously during the addition. After the addition is complete, adjust the pH of the system to 4-6, let it stand for 20h, dry under reduced pressure, wash 5 times with distilled water, and dry at 105℃ to obtain the microbial agent carrier.

[0093] The micronutrient fertilizer is composed of magnesium sulfate, diammonium humate ferric sulfate, copper sulfate monohydrate, zinc sulfate monohydrate, manganese sulfate, and sodium molybdate in a mass ratio of 1:1:1:1:1:1.

[0094] The encapsulating agent is modified gum arabic, and the preparation method includes:

[0095] S10. Weigh 1g of chitosan and dissolve it in 20mL of 4wt% acetic acid solution. Add 85wt% phosphoric acid solution dropwise at a ratio of 1:6 to the volume of the acetic acid solution. Heat to 60℃ and stir for 15h. After the treatment is completed, pour it into 3 times the volume of ethanol, collect the precipitate, wash it 3 times with ethanol, and dry it at 60℃ to obtain phosphorylated chitosan.

[0096] S11. Dissolve phosphorylated chitosan in distilled water to prepare a 3% phosphorylated chitosan solution; dissolve gum arabic in a 2.5% sodium hydroxide solution, heat the solution to 50°C, and then dilute with distilled water to prepare a 4% gum arabic solution.

[0097] S12. The phosphorylated chitosan solution is slowly added to the gum arabic solution, with a volume ratio of gum arabic solution to phosphorylated chitosan solution of 3:1. The mixture is stirred at 60°C and 600 rpm for 4 hours. The pH of the system is then adjusted to 5-6. After filtration, the mixture is washed 5 times with distilled water and dried at 60°C to obtain the modified gum arabic.

[0098] The preparation method of the above-mentioned disease-resistant crop-specific fertilizer includes the following steps:

[0099] Step 1: Preparation of nutrient core: Weigh nitrogen fertilizer, phosphorus fertilizer, potassium fertilizer and synergist according to the weight ratio, mix evenly and granulate to make fertilizer granules. Place the fertilizer granules at 42℃ for constant temperature drying for 2 hours, then add a coating device and spray molasses to cover the surface of the nutrient core to obtain a nutrient core with a diameter of 2.8mm.

[0100] Step 2, covering the microbial inoculant film: the microbial protective agent and the microbial inoculant carrier are added into the liquid microbial inoculant, and the mixture is shaken for 15 min, then the solid is collected by filtration and freeze-dried to obtain the microbial inoculant film material. Then the microbial inoculant film material is sprayed on the surface of the nutrient core to obtain the nutrient core coated with the microbial inoculant film, and the diameter is 3.2 mm.

[0101] Step 3, covering the trace element film: the nutrient core coated with the microbial inoculant film is heated to 42℃, and the coating agent is sprayed on the surface of the nutrient core coated with the microbial inoculant film, and then the trace element fertilizer is further sprayed on the surface. After cooling and drying, the disease-resistant special fertilizer for crops is obtained, and the diameter is 3.7 mm.

[0102] Comparative Example 1

[0103] A granular fertilizer, which is different from Example 1 in that no film coating treatment is performed, and no microbial inoculant carrier, microbial protective agent and coating agent is added, and other components are unchanged.

[0104] The fertilizer is prepared by granulation and screening, and the diameter of the fertilizer particles is 3.7 mm. The fertilizer contains urea 37 parts, monoammonium phosphate 22 parts, potassium chloride 18 parts, humic acid 4 parts, molasses 1 part, microbial inoculant 1.5 parts (containing Bacillus subtilis with an effective viable count of not less than 200 million / g, Bacillus mycoides with an effective viable count of not less than 200 million / g, and Pseudomonas fluorescens with an effective viable count of not less than 500 million / g), and trace element fertilizer 7 parts (consisting of magnesium sulfate, diammonium iron oxalate, copper sulfate monohydrate, zinc sulfate monohydrate, manganese sulfate and sodium molybdate in a mass ratio of 1:1:1:1:1:1).

[0105] Comparative Example 2

[0106] A film-coated granular fertilizer, which is different from Example 1 in that no microbial protective agent is added, the microbial inoculant carrier is replaced by ordinary diatomite, and the coating agent is replaced by gum arabic, and other components are unchanged.

[0107] The fertilizer is granular, and comprises from inside to outside a nutrient core, a microbial agent coating, and a medium and trace element coating. The nutrient core comprises, by weight, 37 parts of urea, 22 parts of monoammonium phosphate, 18 parts of potassium chloride, 4 parts of humic acid, and 1 part of molasses. The microbial agent coating comprises 1.5 parts of a liquid microbial agent (consisting of Bacillus subtilis, Bacillus mycoides, and Pseudomonas fluorescens, wherein the effective viable count of Bacillus subtilis is not less than 200 million / mL, the effective viable count of Bacillus mycoides is not less than 200 million / mL, and the effective viable count of Pseudomonas fluorescens is not less than 500 million / mL), 4 parts of a microbial agent carrier (ordinary diatomite), and 1.5 parts of a microbial protective agent (the same as in Example 1). The medium and trace element coating comprises 7 parts of a medium and trace element fertilizer (consisting of magnesium sulfate, diammonium iron yellow humic acid, copper sulfate monohydrate, zinc sulfate monohydrate, manganese sulfate, and sodium molybdate at a mass ratio of 1:1:1:1:1:1), and 0.8 parts of a wrapping agent (Arabic gum).

[0108] Comparative Example 3

[0109] A coated granular fertilizer, which is different from Example 1 in that the microbial agent carrier is replaced by ordinary diatomite, the wrapping agent is replaced by Arabic gum and chitosan, and the other components remain unchanged.

[0110] The fertilizer is granular, and comprises from inside to outside a nutrient core, a microbial agent coating, and a medium and trace element coating. The nutrient core comprises, by weight, 37 parts of urea, 22 parts of monoammonium phosphate, 18 parts of potassium chloride, 4 parts of humic acid, and 1 part of molasses. The microbial agent coating comprises 1.5 parts of a liquid microbial agent (consisting of Bacillus subtilis, Bacillus mycoides, and Pseudomonas fluorescens, wherein the effective viable count of Bacillus subtilis is not less than 200 million / mL, the effective viable count of Bacillus mycoides is not less than 200 million / mL, and the effective viable count of Pseudomonas fluorescens is not less than 500 million / mL), 4 parts of a microbial agent carrier (ordinary diatomite), and 1.5 parts of a microbial protective agent (the same as in Example 1). The medium and trace element coating comprises 7 parts of a medium and trace element fertilizer (consisting of magnesium sulfate, diammonium iron yellow humic acid, copper sulfate monohydrate, zinc sulfate monohydrate, manganese sulfate, and sodium molybdate at a mass ratio of 1:1:1:1:1:1), and 0.8 parts of a wrapping agent (Arabic gum and chitosan at a mass ratio of 7.5:2).

[0111] Comparative Example 4

[0112] A conventional compound fertilizer with a nitrogen-phosphorus-potassium ratio of 15-15-15.

[0113] Experimental detection

[0114] The test point is selected in a tomato planting area in Jingmen City, Hubei Province, and the basic physicochemical properties of the soil are as follows: pH = 7.41, organic matter content 3.26%, alkali-hydrolyzable nitrogen 92.4 mg / kg, available phosphorus 25.6 mg / kg, and available potassium 167.7 mg / kg. The test adopts a randomized block design, and the plot area is 60 m 2 , examples 1-3, comparative examples 1-4, a total of 7 treatments, each treatment is provided with 3 repetitions, planting adopts the ridge planting method, and the fertilization amount of each treatment is 40 kg / mu. Except that the types of fertilizers are different, the other field measures such as sowing, watering and weeding are consistent. Tomatoes are picked for determination of soluble sugar, vitamin C and lycopene content, and calculation of yield per mu, and the disease incidence of early blight, gray mold, late blight and leaf mold is also determined.

[0115] Table 1 comparison of quality indicators and yield indicators of tomatoes under different treatments

[0116]

[0117] From the quality indicators, compared with the conventional compound fertilizer (comparative example 4) and the fertilizer without adopting the double-layer coating structure (comparative example 1), after applying the disease-resistant crop special fertilizer of the application, the soluble sugar content, vitamin C content and lycopene content of the tomatoes are significantly improved, and compared with comparative examples 2 and 3, the improvement is also to a certain extent. From the yield indicators, compared with the conventional compound fertilizer (comparative example 4) and the fertilizer without adopting the double-layer coating structure (comparative example 1), after applying the disease-resistant crop special fertilizer of the application, the tomato yield is increased by more than 17.03% and 10.79% respectively, and compared with comparative examples 2 and 3, the improvement is also to a certain extent.

[0118] Table 2 influence of different treatments on disease incidence of tomatoes

[0119] Quality indicators Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Early blight 1.9％ 2.0％ 2.3％ 8.5％ 5.8％ 4.2％ 13.4％ Grey mould 2.4％ 2.7％ 2.5％ 16.1％ 6.2％ 4.9％ 26.2％ Late blight 0.8％ 1.1％ 1.0％ 12.2％ 6.1％ 3.0％ 18.2％ Leaf mould 1.8％ 1.9％ 2.3％ 14.8％ 8.2％ 5.6％ 22.3％

[0120] As can be seen from Table 2, compared with the conventional compound fertilizer (comparative example 4) and the fertilizer without adopting the double-layer coating structure (comparative example 1), after applying the disease-resistant crop special fertilizer of the application, the number of diseased plants of early blight, gray mold, late blight and leaf mold of tomatoes is significantly reduced, and compared with comparative examples 2 and 3, the improvement is also to a certain extent.

[0121] In summary, the disease-resistant crop special fertilizer provided by the application can improve the quality indicators and yield of tomatoes, and can significantly improve the influence of early blight, gray mold, late blight and leaf mold on tomatoes.

[0122] In the description of the specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the specification, the illustrative description of the above terms should not be understood as necessarily referring to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate different embodiments or examples described in the specification.

[0123] Although the embodiments of the present application have been shown and described above, it is understood that the above-described embodiments are exemplary, and should not be construed as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above-described embodiments within the scope of the present application.

Claims

1. A disease-resistant crop-specific fertilizer, characterized by, The nutrient core comprises 35-40 parts of nitrogen fertilizer, 20-25 parts of phosphorus fertilizer, 15-20 parts of potassium fertilizer, 3-5 parts of synergist and 1-1.5 parts of molasses by weight. The preparation method of the microbial agent carrier comprises: S1, grinding diatomite and passing it through a 150-180 mesh sieve, adding 1 mol / L sulfuric acid solution, stirring for 1.5-2 hours, then washing with water until the filtrate is neutral, and then drying at 105 DEG C to obtain aged diatomite; S2, adding manganese sulfate and iron sulfate to deionized water to form a sulfate solution; adding the aged diatomite, mixing thoroughly and uniformly to obtain a diatomite mixture; S3, adding humic acid into a sodium hydroxide solution with pH = 8-9, stirring until it is fully dissolved to obtain a humic acid solution; adding the humic acid solution dropwise into the diatomite mixture, continuously stirring during the dropping process, adjusting the pH of the system to 4-6 after the dropping is completed, standing for 10-20 hours, drying under reduced pressure, washing with distilled water for 3-5 times, and drying at 105 DEG C to obtain the microbial agent carrier.

2. The disease-resistant crop-specific fertilizer according to claim 1, characterized in that, The nitrogen fertilizer is one or more of urea, ammonium bicarbonate, ammonium sulfate, ammonium chloride, sodium nitrate, calcium nitrate and ammonium nitrate; the phosphorus fertilizer is one or more of monoammonium phosphate, diammonium phosphate, ammonium phosphate, ammonium polyphosphate, superphosphate, triple superphosphate, calcium magnesium phosphate and phosphate rock powder; the potassium fertilizer is one or more of potassium chloride and potassium sulfate.

3. The disease-resistant crop-specific fertilizer according to claim 1, characterized in that, The synergist is one or more of humic acid, alginic acid, chitosan and amino acid.

4. The disease-resistant crop-specific fertilizer according to claim 1, characterized in that, The medium trace element fertilizer is one or more of compounds of calcium, magnesium, iron, copper, zinc, manganese and molybdenum.

5. The disease-resistant crop-specific fertilizer according to claim 1, characterized in that, The liquid microbial agent solution is composed of Bacillus subtilis, Bacillus mycoides and Pseudomonas fluorescens, wherein the effective viable count of Bacillus subtilis is not less than 200 million / mL, the effective viable count of Bacillus mycoides is not less than 200 million / mL, and the effective viable count of Pseudomonas fluorescens is not less than 500 million / mL.

6. The disease-resistant crop-specific fertilizer according to claim 1, characterized in that, The microbial protective agent is a mixture of brown algal oligosaccharide and rhamnolipid, and the mass ratio of brown algal oligosaccharide to rhamnolipid is 1:1-1.

5.

7. The disease-resistant crop-specific fertilizer according to claim 1, characterized in that, The wrapping agent is modified gum arabic, and the preparation method comprises: S10, weighing chitosan and dissolving it in acetic acid solution, adding phosphoric acid solution, heating to 50-60 DEG C, stirring for 10-15 hours, after the treatment is completed, pouring into ethanol, collecting the precipitate, washing with ethanol for 3 times, drying at 60 DEG C to obtain phosphated chitosan; S11, dissolving the phosphated chitosan in distilled water to prepare a phosphated chitosan solution; dissolving gum arabic in a sodium hydroxide solution first, heating the solution to 50 DEG C, then diluting with distilled water to prepare a gum arabic solution; S12, slowly add the phosphorylated chitosan solution into the gum arabic solution, stirring at 600 rpm for 2-4 h at 50-60℃, then adjust the pH of the system to 5-6, filter and wash with distilled water for 3-5 times, dry at 60℃ to obtain the modified gum arabic.

8. A method of preparing the disease-resistant crop-specific fertilizer according to claim 1, characterized by, The method comprises the following steps: Step 1, preparing the nutrient core: according to the weight ratio, weigh the nitrogen fertilizer, phosphorus fertilizer, potassium fertilizer and synergist, mix uniformly, granulate to prepare the fertilizer particles, place the fertilizer particles in a constant temperature oven at 40-42℃ for 2 h, then add a coating device, spray molasses on the surface of the nutrient core to prepare the nutrient core; Step 2, covering the microbial inoculant coating: add the microbial protective agent and microbial inoculant carrier into the liquid microbial inoculant, fully shake for 10-15 min, filter and collect the solid, freeze-dry to prepare the microbial inoculant coating material, then cover the microbial inoculant coating material on the surface of the nutrient core to prepare the nutrient core covered with the microbial inoculant coating; Step 3, covering the medium trace element coating: heat the nutrient core covered with the microbial inoculant coating to 40-42℃, spray the coating agent on the nutrient core covered with the microbial inoculant coating, then further spray the medium trace element fertilizer on the surface, cool and dry to prepare the disease-resistant special fertilizer for crops.

9. The method of claim 8, wherein the disease-resistant crop-specific fertilizer is prepared by mixing the disease-resistant crop-specific fertilizer with a carrier, and then drying the mixture. The diameter of the nutrient core in Step 1 is 2.6-2.8 mm; the diameter of the nutrient core covered with the microbial inoculant coating in Step 2 is 3.0-3.2 mm; and the diameter of the disease-resistant special fertilizer for crops in Step 3 is 3.5-3.7 mm.

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