Organic foliar fertilizer and preparation method thereof
Through heating, ultrasonic treatment and ingredient composite of methylbacterium single-cell protein fermentation broth, efficient organic foliar fertilizer was prepared, solving the problem of low utilization rate of nutrients in the prior art, and achieving efficient crop absorption and soil improvement effects.
Patent Information
- Application Number
- CN202510471890.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-15
- Publication Date
- 2025-07-11
AI Technical Summary
In the prior art, the supernatant content of the single-cell protein fermentation broth of methylbacterium is low, and the concentration of directly used as foliar fertilizer is too low and the utilization rate is low, resulting in a large loss during spraying, resulting in low crop utilization rate.
By heating and low-frequency ultrasonic treatment of the fermentation broth, chitosan, nanohumidic acid, dimethyl silicone oil and polyglycerides are enzymatically dissolved and added ingredients such as chitosan, nanohumidic acid, dimethyl silicone oil and polyglycerides to form a stable emulsion, increasing foliar adhesion and permeability, and adding Bacillus subtilis spores to improve soil structure.
It improves the nutrient concentration and utilization rate of foliar fertilizer, increases the absorption of nutrients by crops, improves the organic matter content and granular structure of the soil, extends the shelf life and improves the yield and quality of crops.
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Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of foliar fertilizers, and particularly relates to an organic foliar fertilizer and a preparation method thereof. Background Art
[0002] Foliar fertilization is to directly apply the nutrients required by crops to the leaf surface, and make up for the deficiency of root absorption of nutrients by absorbing nutrients through the leaves, so as to improve crop yield, nutrient concentration and plant reproduction efficiency, etc. Organic foliar fertilizers are widely used in the production of organic agricultural products because they are rich in organic components that promote crop growth. In the prior art process of using methylobacteria to produce single-cell protein with methanol as a carbon source, the fermentation broth is separated by centrifugation into a cell concentrate and a waste supernatant. The cell concentrate is dried to make a microbial protein product; the supernatant still contains free amino acids, polypeptides, nucleic acids and inorganic salts, etc., and direct disposal will cause waste; however, the content of its nutrient components is low, and directly used as a foliar fertilizer, the concentration is too low, and if methods such as concentration are used for treatment, due to the high treatment cost, there is no economic benefit. In addition, during the process of foliar fertilizer application, due to the inherent lotus leaf effect of the crop leaf surface, the amount of foliar fertilizer sprayed on the crop leaf surface that can adhere to the leaf surface is small, about 60%, and the loss of foliar fertilizer during spraying is large, and the utilization rate of the crop is low. Summary of the Invention
[0003] The object of the present invention is to prepare an organic foliar fertilizer with high foliar utilization rate by using the fermentation broth of methylobacteria single-cell protein.
[0004] The technical solution of the present invention is as follows:
[0005] A preparation method of an organic foliar fertilizer, comprising the following steps:
[0006] Step 1, heating the fermentation broth for producing single-cell protein bacteria to 62-68°C and keeping it warm for 100-120 min; during the heat preservation process, ultrasonic treatment is carried out, the frequency of the ultrasonic wave is 18-20 Hz, and the power is 150-200 W;
[0007] Step 2, cooling to 35-45°C, adjusting the pH value to 6.0-7.5; adding neutral protease and nuclease for enzymatic hydrolysis for 3-5 hours, and inactivating the enzyme;
[0008] Step 3, centrifuging to obtain a supernatant;
[0009] Step 4, adding chitosan, nano-humic acid and trace element additives to the supernatant, mixing evenly to obtain a pretreatment solution; the addition amount of chitosan is 0.1-0.3 wt% of the supernatant, and the addition amount of nano-humic acid is 0.1-1.0 wt% of the supernatant;
[0010] Step 5: Add dimethyl silicone oil and polyglycerol esters to the pretreatment liquid. The addition amount of the dimethyl silicone oil is 0.05 - 0.20 wt% of the supernatant, and the addition amount of the polyglycerol esters is 0.1 - 0.2 wt% of the supernatant. Homogenize using a high-pressure homogenizer to make the particle size D 90 ≤200 nm;
[0011] Step 6: Add Bacillus subtilis spores, and the addition amount is 0.10 - 0.15 wt% of the supernatant; mix evenly;
[0012] Step 7: Adjust the pH value to 5.8 - 6.2 to obtain the organic foliar fertilizer.
[0013] In the preparation method of the organic foliar fertilizer of the present invention, while the fermentation broth for producing single-cell protein thalli is kept at 62 - 68 °C, low-frequency ultrasonic treatment is carried out, so that the permeability of most of the cell walls of the single-cell protein thalli produced by fermentation increases, and a small part of the relatively fragile cell walls of the thalli directly rupture, thereby releasing more nutrients such as proteins, fats, carbohydrates, nucleic acids, vitamins, and inorganic compounds inside the cells. The proteins and nucleic acids in these nutrients are enzymatically hydrolyzed into soluble amino acids, small peptides, or free amino acids, etc. by neutral protease and nuclease in Step 2, and thus enter the supernatant during the centrifugal separation in Step 3, increasing the concentration of soluble amino acids, small peptides, free amino acids, carbohydrates, nucleic acids, vitamins, and inorganic compounds in the supernatant. For those thalli cells with intact cell walls, their cell walls are also fully activated under the condition of low-frequency ultrasonic treatment, increasing the permeability. After being separated in Step 3, they become high-quality thalli proteins with more easily absorbable nutritional components.
[0014] Chitosan is added in Step 4. There are a large number of hydroxyl groups and amino groups in the chitosan molecule, which can chelate with metal ions. Under the acidic action of nano-humic acid, the carboxyl groups of amino acids can combine with the amino groups in chitosan and form coordination bonds with trace elements. The synergistic effect of chitosan and nano-humic acid promotes the chelation of amino acids with trace elements, which is beneficial to the absorption of trace elements by leaves and improves the biological utilization rate of trace elements. Due to the existence form of the complex, it can effectively avoid the formation of insoluble precipitates by phytic acid, fibers, etc. and free trace elements, which hinder the absorption of trace elements.
[0015] The chitosan, nano-humic acid added in Step 4, and the dimethyl silicone oil and polyglycerol esters added in Step 5 are evenly dispersed in the pretreatment liquid after being homogenized by a high-pressure homogenizer, and the particle size D of the solid particles therein 90≤200 nm. Dimethyl silicone oil itself has a small surface tension and a low HLB value. Its molecular structure contains a large number of lipophilic groups. Polyglycerol esters have many hydrophilic hydroxyl groups and have both hydrophilic and lipophilic dual characteristics, with good emulsifying properties. The combination of dimethyl silicone oil and polyglycerol esters, on the one hand, enables the organic substances in the pretreatment liquid to be well dispersed in the liquid, forming a stable emulsion; on the other hand, the chitosan, nano-humic acid and other nano-scale solid particulate substances impregnated with dimethyl silicone oil and polyglycerol esters in the foliar fertilizer strike the crop leaves during the spraying process, microscopically changing the villus structure and physical state of the leaves, increasing the adhesion performance and permeability of the leaves, making the plant leaves more hydrophilic and having better adhesion, enabling the liquid and nano-scale solid small particles in the foliar fertilizer to better adhere to the leaves, increasing the rapid spreading, wetting, retention and penetration of nutrients on the leaves, and being beneficial to the rapid absorption of nutrients. The chitosan, nano-humic acid that directly fall into the soil during spraying and the above components that enter the soil after being washed by rain later will increase the organic matter content of the soil.
[0016] After the Bacillus subtilis spores added in Step 6 colonize in the sedimented soil, they secrete extracellular polysaccharides, which can improve the soil aggregate structure.
[0017] Preferably, trehalose is also added to the supernatant in Step 4, and the addition amount is 0.5 - 1.0 wt% of the supernatant. Trehalose can stabilize the amino acid structure, prevent the decomposition of amino acids in the foliar fertilizer during the storage period, and extend the shelf life of the foliar fertilizer.
[0018] Preferably, the trace element additive is a soluble salt of at least one element among calcium, iron, manganese, zinc and selenium.
[0019] Preferably, the addition amount of the neutral protease is 0.1 - 0.5 wt% of the fermentation broth, and the addition amount of the nuclease is 0.1 - 0.5 wt% of the fermentation broth; potassium sorbate is also added to the supernatant in Step 4, and the addition amount of potassium sorbate is 0.03 - 0.05 wt% of the supernatant. Potassium sorbate can inhibit the growth of molds and prevent the foliar fertilizer from mildewing.
[0020] Preferably, lignosulfonate is also added to the supernatant in Step 4, and the addition amount is 1.0 - 2.0 wt% of the supernatant. Lignosulfonate is beneficial to further improve the permeability of the foliar fertilizer on the leaves and increase the organic matter content of the soil after the fertilizer falls into the soil.
[0021] Preferably, the trace element additive is Fe-EDTA, and the addition amount is 0.1-0.15wt% of the supernatant; and in step 4, 0.3-0.5wt% of urea based on the supernatant is also added. More preferably, in step 4, 0.03-0.05wt% of γ-aminobutyric acid based on the supernatant is also added. Foliar fertilizer with urea and γ-aminobutyric acid added is more suitable for leafy vegetables, which can increase the thickness of leafy vegetables, reduce nitrate content, and enhance stress resistance.
[0022] Preferably, in step 4, 0.1-0.3wt% of potassium dihydrogen phosphate and 0.03-0.05wt% of sodium borate are also added based on the supernatant. Potassium dihydrogen phosphate and sodium borate can promote sugar accumulation, which can effectively increase the soluble solids of fruits and vegetables, and extend the picking period of fruits and vegetables. Such foliar fertilizer is more suitable for sweet fruits and vegetables. More preferably, in step 4, 0.01-0.02wt% of methyl jasmonate or 0.01-0.02wt% of perillyl alcohol are also added based on the supernatant. Foliar fertilizers with the addition of methyl jasmonate or perillyl alcohol are beneficial to the synthesis of aroma substances in fruits, making fruits and vegetables more fragrant.
[0023] The invention provides an organic foliar fertilizer, which is prepared by the method.
[0024] The technical effects of the present invention are:
[0025] The method for preparing the organic foliar fertilizer of the present invention comprises the following steps: subjecting the fermented liquid to low-frequency ultrasonic treatment while keeping it warm to destroy part of the single-cell protein bacteria, releasing more nutrients into the supernatant to increase the concentration, adding chitosan, nano-humic acid, dimethyl silicone oil and polyglycerol ester to fully emulsify, and adding Bacillus subtilis spores to prepare the foliar fertilizer, thereby making full effective use of the supernatant of the methyl bacterium single-cell protein fermentation liquid, and improving the comprehensive economic benefits of the single-cell protein production process. The organic foliar fertilizer prepared by the present invention comprises chitosan, nano-humic acid, dimethyl silicone oil and polyglycerol ester, which synergistically improve the attachment and absorption of the foliar fertilizer by the crop leaves, and the nutrients falling into the soil improve the organic matter content of the soil and improve the aggregate structure of the soil. DETAILED DESCRIPTION
[0026] The present invention is described in detail below in conjunction with the embodiments. The main raw materials used in the embodiments of the present invention are from the following sources:
[0027] Dimethyl silicone oil, Guangzhou Xinguan Chemical Technology Co., Ltd., model PMX-200, viscosity 100CS;
[0028] Polyglycerol ester, Jiangsu Libin Bioengineering Co., Ltd., model 0688;
[0029] Chitosan, Nanjing Xinjiehui Biotechnology Co., Ltd., model number xjh2858.
[0030] The single-cell protein bacteria used in the following examples and comparative examples are from the same batch of fermentation broth, which is prepared using methylotrophic bacteria as the fermentation bacteria.
[0031] Example 1
[0032] Prepare an organic foliar fertilizer, the method is as follows:
[0033] Step 1, heat the fermentation broth for producing single-cell protein bacteria to 62 - 65 °C and keep warm for 100 min; perform ultrasonic treatment during the heat preservation process, the frequency of the ultrasonic wave is 18 Hz, and the power is 150 W.
[0034] Step 2, cool down to 35 °C, adjust the pH value to 6.0; add neutral protease and nuclease for enzymatic hydrolysis for 3 hours, and inactivate the enzymes; among them, the addition amount of neutral protease is 0.5 wt% of the fermentation broth, and the addition amount of nuclease is 0.1 wt% of the fermentation broth.
[0035] Step 3, perform centrifugal separation to obtain the supernatant;
[0036] Step 4, add chitosan, nano-humic acid and trace element additive to the supernatant, mix evenly to obtain the pretreatment liquid; the addition amount of chitosan is 0.1 wt% of the supernatant, and the addition amount of nano-humic acid is 1.0 wt% of the supernatant; the trace element additive is 0.1 wt% of Fe-EDTA, 0.15 wt% of Zn-EDT, and 0.05 g / L of sodium selenite based on the supernatant.
[0037] Step 5, add dimethyl silicone oil and polyglycerol ester to the pretreatment liquid, the addition amount of dimethyl silicone oil is 0.05 wt% of the supernatant, and the addition amount of polyglycerol ester is 0.1 wt% of the supernatant. Homogenize with a high-pressure homogenizer at 80 MPa to make the particle size D 90 be 190 nm.
[0038] Step 6, add Bacillus subtilis spores, the addition amount is 0.10 wt% of the supernatant, and mix evenly.
[0039] Step 7, adjust the pH value to 5.8 to obtain the organic foliar fertilizer.
[0040] Example 2
[0041] Prepare an organic foliar fertilizer, the method is as follows:
[0042] Step 1, heat the fermentation broth for producing single-cell protein bacteria to 65 - 68 °C and keep warm for 120 min; perform ultrasonic treatment during the heat preservation process, the frequency of the ultrasonic wave is 20 Hz, and the power is 200 W.
[0043] Step 2: Cool down to 45°C and adjust the pH value to 7.5; add neutral protease and nuclease for enzymatic hydrolysis for 5 hours, and inactivate the enzymes; among them, the addition amount of neutral protease is 0.1 wt% of the fermentation broth, and the addition amount of nuclease is 0.5 wt% of the fermentation broth.
[0044] Step 3: Centrifuge to obtain the supernatant.
[0045] Step 4: Add chitosan, nano-humic acid and trace element additive to the supernatant, mix evenly to obtain the pretreatment liquid; the addition amount of chitosan is 0.3 wt% of the supernatant, and the addition amount of nano-humic acid is 0.1 wt% of the supernatant; the trace element additive is 0.15 wt% of Fe-EDTA, 0.15 wt% of Zn-EDT, and 0.05 g / L of sodium selenite based on the supernatant.
[0046] Step 5: Add dimethyl silicone oil and polyglycerol ester to the pretreatment liquid. The addition amount of dimethyl silicone oil is 0.20 wt% of the supernatant, and the addition amount of polyglycerol ester is 0.2 wt% of the supernatant. Homogenize with a high-pressure homogenizer at 80 MPa to make the particle size D 90 be 180 nm.
[0047] Step 6: Add Bacillus subtilis spores, and the addition amount is 0.15 wt% of the supernatant, and mix evenly.
[0048] Step 7: Adjust the pH value to 6.2 to obtain the organic foliar fertilizer.
[0049] Example 3
[0050] Prepare an organic foliar fertilizer.
[0051] The only difference between the preparation method of this example and that of Example 1 lies in Step 4. The Step 4 of this example is as follows:
[0052] Step 4: Add chitosan, trehalose, nano-humic acid, urea and trace element additive to the supernatant, mix evenly to obtain the pretreatment liquid; the addition amount of chitosan is 0.3 wt% of the supernatant, the addition amount of trehalose is 0.5 wt% of the supernatant, and the addition amount of nano-humic acid is 1.0 wt% of the supernatant; the addition amount of urea is 0.5 wt% of the supernatant. The trace element additive is 0.10 wt% of Fe-EDTA, 0.15 wt% of Zn-EDT, and 0.05 g / L of sodium selenite based on the supernatant.
[0053] The remaining steps are exactly the same as those in Example 1.
[0054] Example 4
[0055] Prepare an organic foliar fertilizer.
[0056] The only difference in the preparation method between this example and Example 1 lies in Step 4, and Step 4 of this example is as follows:
[0057] Step 4: Add chitosan, trehalose, nano-humic acid, sodium lignosulfonate, potassium sorbate, urea and trace element additive to the supernatant, and mix evenly to obtain a pretreatment solution; the addition amount of chitosan is 0.3 wt% of the supernatant, the addition amount of trehalose is 1.0 wt% of the supernatant, and the addition amount of nano-humic acid is 1.0 wt% of the supernatant; the addition amount of sodium lignosulfonate is 2.0 wt% of the supernatant; the addition amount of potassium sorbate is 0.05 wt% of the supernatant; the addition amount of urea is 0.3 wt% of the supernatant. The addition amount of the trace element additive is 0.15 wt% of Fe-EDTA, 0.15 wt% of Zn-EDT, and 0.05 g / L of sodium selenite based on the supernatant.
[0058] The remaining steps are exactly the same as those in Example 1.
[0059] Example 5
[0060] Prepare an organic foliar fertilizer.
[0061] The only difference in the preparation method between this example and Example 1 lies in Step 4, and Step 4 of this example is as follows:
[0062] Step 4: Add chitosan, nano-humic acid, sodium lignosulfonate, γ-aminobutyric acid, potassium sorbate, urea and trace element additive to the supernatant, and mix evenly to obtain a pretreatment solution; the addition amount of chitosan is 0.3 wt% of the supernatant, the addition amount of nano-humic acid is 1.0 wt% of the supernatant; the addition amount of sodium lignosulfonate is 1.0 wt% of the supernatant; the addition amount of γ-aminobutyric acid is 0.04 wt% of the supernatant; the addition amount of potassium sorbate is 0.05 wt% of the supernatant; the addition amount of urea is 0.3 wt% of the supernatant. The trace element additive is 0.15 wt% of Fe-EDTA, 0.15 wt% of Zn-EDT, and 0.05 g / L of sodium selenite based on the supernatant.
[0063] The remaining steps are exactly the same as those in Example 1.
[0064] Example 6
[0065] Prepare an organic foliar fertilizer.
[0066] The only difference in the preparation method between this example and Example 2 lies in Step 4, and Step 4 of this example is as follows:
[0067] Step 4: Add chitosan, nano-humic acid, KH2PO4, NaBO2, and trace element additive into the supernatant, mix evenly to obtain a pretreatment solution. The addition amount of chitosan is 0.3 wt% of the supernatant, the addition amount of nano-humic acid is 0.5 wt% of the supernatant; the addition amount of KH2PO4 is 0.2 wt% of the supernatant; the addition amount of NaBO2 is 0.04 wt% of the supernatant. The trace element additive is 0.15 wt% of Fe-EDTA, 0.15 wt% of Zn-EDT, and 0.05 g / L of sodium selenite based on the supernatant.
[0068] The remaining steps are exactly the same as those in Example 2.
[0069] Example 7
[0070] Prepare an organic foliar fertilizer.
[0071] The only difference in the preparation method between this example and Example 6 lies in Step 4. In Step 4 of this example, methyl jasmonate at 0.01 wt% based on the supernatant is further added to the supernatant.
[0072] The remaining steps are exactly the same as those in Example 6.
[0073] Example 8
[0074] Prepare an organic foliar fertilizer.
[0075] The only difference in the preparation method between this example and Example 6 lies in Step 4. In Step 4 of this example, perillyl alcohol at 0.02 wt% based on the supernatant is further added to the supernatant.
[0076] The remaining steps are exactly the same as those in Example 6.
[0077] Comparative Example 1
[0078] Prepare an organic foliar fertilizer.
[0079] The difference between the method used in this comparative example and that in Example 1 is that there is no Step 1. It directly starts from Step 2, that is, directly use the fermentation broth for producing single-cell protein bacteria and control the temperature to 35°C, adjust the pH value to 6.0; add neutral protease and nuclease and enzymolyze for 3 hours, inactivate the enzyme; among them, the addition amount of neutral protease is 0.5 wt% of the fermentation broth, and the addition amount of nuclease is 0.1 wt% of the fermentation broth. Then carry out Steps 3, 4, 5, 6, and 7 in the same method as in Example 1 to obtain the organic foliar fertilizer.
[0080] Comparative Example 2
[0081] Prepare an organic foliar fertilizer.
[0082] The method used in this comparative example is different from that in Example 1 in Step 5. In Step 5 of this comparative example, dimethyl silicone oil was not added, and the specific steps are as follows:
[0083] Step 5: Add polyglycerol ester to the pretreatment liquid. The addition amount of polyglycerol ester is 0.15 wt% of the supernatant. Homogenize using a high-pressure homogenizer at 80 MPa to make the particle size D 90 be 190 nm.
[0084] The remaining steps are exactly the same as those in Example 1.
[0085] Comparative Example 3
[0086] Prepare an organic foliar fertilizer.
[0087] The method used in this comparative example is different from that in Example 1 in Step 5. In Step 5 of this comparative example, polyglycerol ester was not added, and the specific steps are as follows:
[0088] Step 5: Add dimethyl silicone oil to the pretreatment liquid. The addition amount of dimethyl silicone oil is 0.15 wt% of the supernatant. Homogenize using a high-pressure homogenizer at 80 MPa to make the particle size D 90 be 190 nm.
[0089] The remaining steps are exactly the same as those in Example 1.
[0090] Comparative Example 4
[0091] Prepare an organic foliar fertilizer.
[0092] The method used in this comparative example is different from that in Example 1 in Step 4. In Step 4 of this comparative example, nano-humic acid was not added, and the specific steps are as follows:
[0093] Step 4: Add chitosan and trace element additives to the supernatant and mix evenly to obtain a pretreatment liquid; the addition amount of chitosan is 0.1 wt% of the supernatant; the trace element additives are 0.1 wt% of Fe-EDTA, 0.15 wt% of Zn-EDT, and 0.05 g / L of sodium selenite based on the supernatant.
[0094] The remaining steps are exactly the same as those in Example 1.
[0095] Comparative Example 5
[0096] Prepare an organic foliar fertilizer.
[0097] The method used in this comparative example is different from that in Example 1 in Step 4. In Step 4 of this comparative example, chitosan was not added, and the specific steps are as follows:
[0098] Step 4: Add nano-humic acid and trace element additive to the supernatant, mix evenly to obtain a pretreatment solution; the addition amount of nano-humic acid is 1.0 wt% of the supernatant; the trace element additive is 0.1 wt% of Fe-EDTA, 0.15 wt% of Zn-EDT, and 0.05 g / L of sodium selenite based on the supernatant.
[0099] The remaining steps are exactly the same as those in Example 1.
[0100] Comparative Example 6
[0101] Prepare an organic foliar fertilizer.
[0102] The method used in this comparative example is different from that in Example 1 in Step 5. In Step 5 of this comparative example, high-pressure homogenization is not carried out.
[0103] The remaining steps are exactly the same as those in Example 1.
[0104] Test:
[0105] The organic foliar fertilizers prepared in Examples 1 to 8 and Comparative Examples 1 to 6 were respectively subjected to the following tests, and the test results were recorded in Table 1.
[0106] 1. Detection of the organic matter content of the organic foliar fertilizer
[0107] Directly measure the liquid foliar fertilizer, and use the potassium dichromate oxidation method to determine the organic matter content of the organic foliar fertilizer. The test results are recorded in Table 1.
[0108] 2. Evaluation of the shelf life of the organic foliar fertilizer
[0109] Use the accelerated aging test method to evaluate the shelf life of the organic foliar fertilizer. The method is as follows:
[0110] Place the organic foliar fertilizer in a constant temperature and humidity chamber at 40°C and 75% RH for storage. After 90 days (equivalent to 12 months at room temperature), take it out for observation, and use high-performance liquid chromatography to measure the decomposition rate of amino acids. Observe once every 7 days after 90 days. Every 7-day extension is equivalent to one month's extension of the shelf life.
[0111] When the appearance of the organic foliar fertilizer shows stratification, mildew, or the amino acid decomposition rate is greater than 10% in any one of them, it is determined to be qualitatively changed. The qualitative change terminates the evaluation, and the time in the constant temperature and humidity chamber at this time is counted as the shelf life and recorded in Table 1.
[0112] 3. Detection of mildew of the organic foliar fertilizer
[0113] Method: Plate counting method
[0114] Steps:
[0115] 1) Take 10 g of organic foliar fertilizer, add 90 mL of sterile water, and shake for 30 min.
[0116] 2) After dilution, coat it on PDA medium and culture at 28 °C for 72 h.
[0117] 3) Count the colonies. When the number of molds > 1000 CFU / g, it is a high risk; when it is 800 - 1000 CFU / g, it is a medium risk; when it is 800 - 500 CFU / g, it is a low risk; when it is below 500 CFU / g, it is an extremely low risk.
[0118] Record the test results in Table 1.
[0119] Table 1
[0120]
[0121] It can be seen from the data in Table 1 that the organic matter content of the foliar fertilizers prepared in Examples 1 to 8 by using the preparation method of the present invention is relatively high, all above 18.0%; while the organic matter content of the foliar fertilizer prepared in Comparative Example 1 without using the method of the present invention is only 14.1% at most. It can be seen that heating and low-frequency ultrasonic treatment in the first step of using the method of the present invention can effectively release the organic matter in the single-cell protein bacteria. In addition, it can also be seen from Table 1 that the shelf life of the organic foliar fertilizers prepared in Examples 3 and 4 is long, which is 16 months, while the shelf lives of the organic foliar fertilizers prepared in other examples and comparative examples are relatively short, which is 12 months. This is mainly because the trehalose added in the organic foliar fertilizers prepared in Examples 3 and 4 can stabilize the amino acid structure, avoid the decomposition of amino acids in the foliar fertilizer during storage, and extend the shelf life of the foliar fertilizer. It can also be seen from Table 1 that the foliar fertilizers prepared in Examples 4 and 5 are added with potassium sorbate, and the mildew risk is extremely low. The mildew risk of the foliar fertilizer prepared in Example 2 is low; while the mildew risks of the foliar fertilizers prepared in other examples and all comparative examples are medium because they are not added with potassium sorbate.
[0122] Application Example 1
[0123] Divide the planting area of honeydew melons planted in the greenhouse into 15 different planting areas at intervals, and name them Area A1 to A15 respectively, with a distance of more than 3 meters between the areas. Before planting, measure the soil organic matter of each area according to NY / T 1121.6 - 2006 "Soil Testing - Part 6: Determination of Soil Organic Matter" and record them respectively.
[0124] After the melon seedlings are planted, no foliar fertilizer is applied in Area A15; in Areas A1 to A14, spray the foliar fertilizers prepared in each example and each comparative example respectively. The specific fertilization types in each area are shown in Table 2.
[0125] The fertilization plan for areas A1 to A14 is as follows: The fertilization time is during the vine elongation stage and the fruit swelling stage after pollination. When topdressing, dilute the organic foliar fertilizer 50 times and spray it on the melon leaves. The spraying amount should be such that the melon leaves are moist and just have water droplets dripping.
[0126] After the melons in areas A1 to A15 are mature, record the time of picking the first batch of melons. The maturity criteria are: the fruit skin color conversion rate > 90% and the seeds are browned. Record the first picking time of each area and compare it with the first picking time of area A15 respectively, which is the advanced time of the picking period and is recorded in Table 2.
[0127] After the first batch of melons in each planting area are mature, detect their sugar content and soluble solids.
[0128] 1) Sugar content; Use the handheld refractometer method for determination. After determining the sugar content, take the melons harvested in area A1 as the benchmark and calculate the sugar content increase rate. The test results are recorded in Table 2.
[0129] The method for sugar content determination is as follows:
[0130] Put the melons into a blender to make a pulp, drop it on the prism of the refractometer, and directly read the Brix value (%). Repeat 3 times and take the average. Calibrate the refractometer with distilled water (0% Brix) after each measurement.
[0131] Sugar content increase rate == (sugar content of melons in area Ai - sugar content of melons in area A15) / sugar content of melons in area A15 × 100%
[0132] Among them, i = 1 - 14.
[0133] 2) Method for detecting soluble solids:
[0134] Put the melons into a blender to make a pulp, take 10 mL of the sample pulp, and dry it to a constant weight at 105 °C. Calculate the soluble solids increase rate and record the results in Table 2.
[0135] Soluble solids = residue weight (g) / 10 (sample volume, mL) × 100%
[0136] Soluble solids increase rate == (soluble solids of melons in area Ai - soluble solids of melons in area A15) / soluble solids of melons in area A15 × 100%
[0137] Among them, i = 1 - 14.
[0138] 3) Evaluation of the improvement of fruit aroma
[0139] Method: Use headspace solid-phase microextraction GC-MS to analyze the contents of aroma substances: esters (such as ethyl acetate) and aldehydes (hexanal).
[0140] Steps:
[0141] A. Grind 50g of pulp and balance at 40℃ for 30min
[0142] B. Solid phase microextraction fiber adsorbs volatile components, and GC-MS analyzes the content of esters (such as ethyl acetate) and aldehydes (hexanal). The measurement results are compared with the test values of area A15, and the fruity aroma enhancement value is calculated, and the results are recorded in Table 2.
[0143] 4) Determination of soil organic matter improvement ratio:
[0144] After the melon harvest period, after cleaning the melon vines, the soil organic matter in each area was measured according to NY / T 1121.6-2006 "Soil Testing Part 6: Determination of Soil Organic Matter", and the soil organic matter improvement rate was calculated. The results are recorded in Table 2.
[0145] Soil organic matter improvement ratio = (organic matter after fertilization - organic matter before fertilization) / organic matter before fertilization × 100%
[0146] Table 2
[0147]
[0148] From the data in Table 2, it can be seen that the foliar fertilizers prepared by Examples 1 to 8 of the method of the present invention can advance the picking period of melons, especially the foliar fertilizers prepared by Examples 1, 7, and 8 to which potassium dihydrogen phosphate and sodium borate are added, the picking period is advanced the most, and the sugar content and soluble solids are increased the most. The foliar fertilizers prepared by Examples 7 and 8 also highly increase the aroma substances of melons and fruits.
[0149] It can also be seen from the data in Table 2 that the foliar fertilizer prepared in Comparative Example 1, which does not adopt the method of the present invention, does not advance the picking period due to its low organic content, and does not significantly improve the sugar content and soluble solids. The foliar fertilizers prepared in Comparative Examples 2 and 3, although they have a lot of organic content, do not significantly improve the picking period, sugar content and soluble solids. It can be seen that the use of dimethyl silicone oil or polyglycerol ester alone does not improve the absorption of foliar fertilizers much.
[0150] It can also be seen from the data in Table 2 that the foliar fertilizer prepared in Comparative Example 4, which did not adopt the method of the present invention, did not significantly improve the early picking period, sugar content and soluble solids due to the absence of the addition of nano humic acid; the foliar fertilizer prepared in Comparative Example 5, which did not adopt the method of the present invention, did not significantly improve the early picking period, sugar content and soluble solids due to the absence of the addition of chitosan. The foliar fertilizer prepared in Comparative Example 6, due to the lack of high-pressure homogenization, had poor leaf absorption, resulting in no significant improvement in the early picking period, sugar content and soluble solids.
[0151] It can also be seen from the data in Table 2 that the method of the present invention can effectively improve soil organic matter. In particular, for the foliar fertilizers prepared in Examples 7 and 8, lignosulfonate is added, and the soil organic matter is increased the most.
[0152] Application Example 2
[0153] The spinach-growing area in the greenhouse was divided into 15 different regions at intervals, named Region B1 to B15 respectively, with a distance of more than 3 meters between regions. When the spinach seedlings had 3 - 4 true leaves, no foliar fertilizer was applied in Region B15; the foliar fertilizers prepared in each example and each comparative example were sprayed in Regions B1 to B14 respectively. The specific fertilization types for each region are shown in Table 3. When fertilizing, the organic foliar fertilizer was diluted 500 times and then sprayed, and the amount of fertilization was 10 kg per mu. After 45 days of planting, the spinach was harvested, and the leaf thickness was measured using a digital micrometer. The method was as follows: Select the fully expanded leaves in the middle of the plant, avoid the leaf veins, and measure the thickness at 3 points in the middle of the leaf with a micrometer (accuracy 0.01 mm), take the average value, and calculate the leaf thickness increase rate. The results are shown in Table 1.
[0154] Leaf thickness increase rate of Region Bi = (Leaf thickness of Region Bi - Leaf thickness of Region B15) / Leaf thickness of Region B15 × 100%
[0155] where i = 1 - 14.
[0156] Table 3
[0157] Planting area Source of foliar fertilizer Leaf thickness increase rate (%) Area B1 Example 1 6.0 Area B2 Example 2 6.1 Area B3 Example 3 9.0 Area B4 Example 4 8.0 Area B5 Example 5 9.0 Area B6 Example 6 6.0 Area B7 Example 7 6.1 Area B8 Example 8 6.2 Area B9 Comparative example 1 1.0 Area B10 Comparative example 2 3.4 Area B11 Comparative example 3 3.2 Area B12 Comparative example 4 3.6 Area B13 Comparative example 5 3.2 Area B14 Comparative example 6 3.5
[0158] It can be seen from the data in Table 3 that the foliar fertilizers prepared in Examples 1 to 8 of the method of the present invention can all increase the leaf thickness of spinach. In particular, for the foliar fertilizers prepared in Examples 3, 4, and 5 with Fe-EDTA and urea added, the leaf thickness of spinach increases the most. However, the foliar fertilizers prepared in each comparative example have a relatively small increase in leaf thickness.
[0159] It should be noted here that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation to the present invention. In addition, the technical features involved in the various embodiments of the present invention described above can be combined with each other as long as they do not conflict with each other. In addition, the above are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.
Claims
1. A preparation method of an organic foliar fertilizer, characterized in that, It includes the following steps: Step 1: Heat the fermentation broth for producing single-cell protein thalli to 62 - 68 °C and keep warm for 100 - 120 min; perform ultrasonic treatment during the warming process, where the frequency of the ultrasonic wave is 18 - 20 Hz and the power is 150 - 200 W; Step 2: Cool down to 35 - 45 °C, adjust the pH value to 6.0 - 7.5; add neutral protease and nuclease for enzymatic hydrolysis for 3 - 5 hours, and inactivate the enzymes; Step 3: Centrifuge to obtain the supernatant; Step 4: Add chitosan, nano-humic acid, and trace element additive to the supernatant and mix evenly to obtain a pretreatment solution; the addition amount of chitosan is 0.1 - 0.3 wt% of the supernatant, and the addition amount of nano-humic acid is 0.1 - 1.0 wt% of the supernatant; Step 5: Add dimethyl silicone oil and polyglycerol esters to the pretreatment solution. The addition amount of the dimethyl silicone oil is 0.05-0.20 wt% of the supernatant, and the addition amount of the polyglycerol esters is 0.1-0.2 wt% of the supernatant. Homogenize using a high-pressure homogenizer to make the particle size D 90 ≤200 nm; Step 6: Add Bacillus subtilis spores, and the addition amount is 0.10 - 0.15 wt% of the supernatant; mix evenly; Step 7: Adjust the pH value to 5.8 - 6.2 to obtain an organic foliar fertilizer.
2. The preparation method of the organic foliar fertilizer according to claim 1, wherein, Trehalose is also added to the supernatant in Step 4, and the addition amount is 0.5 - 1.0 wt% of the supernatant.
3. The preparation method of the organic foliar fertilizer according to claim 1, characterized in that, The trace element additive is a soluble salt of at least one element among calcium, iron, manganese, zinc, and selenium.
4. The preparation method of the organic foliar fertilizer according to claim 1, characterized in that The addition amount of the neutral protease is 0.1 - 0.5 wt% of the fermentation broth, and the addition amount of the nuclease is 0.1 - 0.5 wt% of the fermentation broth; potassium sorbate is also added to the supernatant in Step 4, and the addition amount of potassium sorbate is 0.03 - 0.05 wt% of the supernatant.
5. The preparation method of the organic foliar fertilizer according to claim 1, wherein, Lignosulfonate is also added to the supernatant in Step 4, and the addition amount is 1.0 - 2.0 wt% of the supernatant.
6. The preparation method of the organic foliar fertilizer according to claim 1, characterized in that The trace element additive is Fe-EDTA, and the addition amount is 0.1 - 0.15 wt% of the supernatant; and 0.3 - 0.5 wt% of urea based on the supernatant is also added in Step 4.
7. The preparation method of the organic foliar fertilizer according to claim 6, characterized in that, 0.03 - 0.05 wt% of γ-aminobutyric acid based on the supernatant is also added in Step 4.
8. The preparation method of the organic foliar fertilizer according to claim 1, wherein, 0.1 - 0.3 wt% of potassium dihydrogen phosphate and 0.03 - 0.05 wt% of sodium borate based on the supernatant are also added in Step 4.
9. The preparation method of the organic foliar fertilizer according to claim 8, characterized in that, 0.01 - 0.02 wt% of methyl jasmonate or 0.01 - 0.02 wt% of perilla alcohol based on the supernatant is also added in Step 4.
10. An organic foliar fertilizer, characterized in that, It is made by the method according to any one of claims 1 to 9.