Special biological bacterial fertilizer for strawberries and preparation method thereof

Abstract

The biogas slurry is mainly used as a raw material, the yield and quality of crops can be improved, nutrient substances in the biogas slurry are easily absorbed by the crops, nutrients needed by growth of the crops can be provided, and therefore the yield and quality of the crops are improved. Researches show that by applying the biogas slurry, the content of soluble sugar, vitamin C, protein, mineral substances and the like of agricultural products can be greatly increased; microorganisms in the biogas slurry can promote decomposition and absorption of substances in the soil and increase the fertility and biological activity of the soil, so that the physical properties and the structure of the soil are improved; biological control of plant diseases and insect pests: butyric acid, indoleacetic acid, gibberellin and other substances contained in the biogas slurry have the effects of expelling and killing insects, also have a strong inhibition effect on various pathogenic bacteria, and are a green biological insecticide; the biogas slurry is recycled as agricultural waste, so that the environmental pollution can be reduced, and the sustainable utilization of resources can be realized.

Description

Technical Field

[0001] The invention relates to the field of strawberry cultivation technology and fertilization, and in particular to a biological fertilizer special for strawberries and a preparation method thereof. Background Art

[0002] Strawberry is a fruit with high nutrition and high economic value. With the development of facility agriculture, the cultivation area of ​​facility strawberry has gradually increased, resulting in continuous cropping of strawberries and restricting the large-scale production of strawberries. Studies have shown that continuous cropping will destroy the structure of soil microbial communities, causing the alternation of dominant soil bacteria, imbalance of soil nutrients, and reduced soil fertility. Microorganisms can effectively improve the microbial community of plant roots, promote the release of soil fixed nutrients, and improve fertilizer utilization.

[0003] Among them, soil microorganisms affect the growth and development of plants in various aspects, and the composition and activity of their communities are also related to plant productivity. Soil is the habitat for the life and reproduction of microorganisms. As organisms in the soil, microorganisms are more sensitive to environmental changes. Generally, moist, warm and fertile neutral soils contain the largest number of microorganisms. There are a large number of microorganisms in the soil, and while decomposing the residues, they also produce metabolites. The composition of the microbial community is a determining factor in the mineralization of soil organic matter. Changes in the composition of the microbial community may affect the decomposition of soil organic matter and the soil respiration rate. Some bacteria, such as actinomycetes, participate in the degradation of polymer compounds such as cellulose, while yeast and sugar fungi also degrade simple compounds such as sugars. Bacteria in the soil are mainly involved in the degradation of simple, soluble substrates, while fungi are decomposers of solid, difficult-to-decompose substrates. In recent years, the study of soil microbial community composition and diversity has become one of the hot topics in the fields of international soil microbiology, soil ecology and global change biology.

[0004] The changes in soil microorganisms are mainly affected by the soil environment and management measures. In terms of soil environment, the physical and chemical properties of the soil, season, soil texture, and vegetation type have an impact on the changes in microorganisms. At the same time, the number of microorganisms will decrease with the increase of soil depth. In terms of management measures, the effects of fertilizers, pesticides, and farming methods on microorganisms are extremely complex. Studies have found that the degree of promotion of soil microorganisms is organic fertilizers > mixed organic and inorganic fertilizers > inorganic fertilizers.

[0005] Beneficial microorganisms in microbial fertilizers can produce sugar substances, improve soil aggregate structure, release plant active factors, promote plant root growth, enhance crop disease resistance, improve crop yield and quality without polluting the environment, and have been widely used in the agricultural field in recent years. At present, microbial fertilizers have a single strain, simple function, high cost, large dosage and inconvenient transportation, which limit their popularization and promotion. It can be seen in patent documents that most biological fertilizers have only one strain. Some fertilizers have many strains, but the carrier raw materials are rare, so it is worth studying and improving. Summary of the invention

[0006] In view of the deficiencies in the above-mentioned prior art, the object of the present invention is to provide a biological fertilizer specifically for strawberries and a preparation method thereof.

[0007] To achieve the above-mentioned purpose, the present invention provides the following technical scheme: a biological fertilizer specially used for strawberries, comprising the following raw materials in parts by weight: 1-100 parts of biogas slurry, 0.1-5 parts of potassium dihydrogen phosphate, 0.1-5 parts of dipotassium hydrogen phosphate, 0.01-0.1 parts of sulfate, 1-20 parts of molasses, 0.1-2 parts of Bacillus subtilis, and 0.1-2 parts of Bacillus licheniformis.

[0008] Furthermore, the biogas slurry is the residue after anaerobic fermentation of the biogas slurry for one month, and the filtrate after filtering and removing solid impurities.

[0009] Furthermore, the filtering refers to screening the biogas slurry through a 35-150 mesh filter.

[0010] Furthermore, the sulfate is any one of potassium sulfate or ammonium sulfate.

[0011] Furthermore, the molasses comprises molasses dry powder, wherein the water content of the molasses is less than 20%.

[0012] As a preferred solution of the present application, a method for preparing a biological fertilizer for strawberries is also included, which is prepared by using the biological fertilizer for strawberries prepared by the above technical solution, and specifically comprises: S1: filtering and pretreating 1-100 portions of the biogas slurry to obtain filtered biogas slurry;

[0013] S2: adding 0.1-5 parts of potassium dihydrogen phosphate, 0.1-5 parts of dipotassium hydrogen phosphate, and 0.01-0.1 parts of sulfate to the filtered biogas slurry in order according to the formula to obtain acidic biogas slurry;

[0014] S3: adding 1-20 parts of molasses to the acidic biogas slurry, inoculating 0.1-2 parts of Bacillus subtilis and 0.1-2 parts of Bacillus licheniformis at the same time, and stirring evenly to obtain a product to be fermented;

[0015] S4: The fermented material is fermented at 16° C.-30° C. for 2-5 days to obtain a biological fertilizer specifically for strawberries.

[0016] Furthermore, the pH value of the acidic biogas slurry is 6-6.5.

[0017] Furthermore, the EC value of the acidic biogas slurry is 5-10S / m.

[0018] Furthermore, the bacterial density of the strawberry-specific biological fertilizer is ≥1*10^6 cfu / ml.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] This application mainly uses biogas slurry as raw material. The application of biogas slurry can greatly increase the soluble sugar, vitamin C, protein, mineral content, etc. of agricultural products, thereby improving crop yield and quality: the nutrients in biogas slurry are easily absorbed by crops and can provide the nutrients needed for crop growth, thereby improving crop yield and quality.

[0021] Improve soil structure: Microorganisms in biogas slurry can promote the decomposition and absorption of substances in the soil, increase soil fertility and biological activity, and thus improve the physical properties and structure of the soil.

[0022] Biological control of pests and diseases: Substances such as butyric acid, indoleacetic acid, and gibberellins contained in biogas slurry have the effects of repelling and killing insects, and have a strong inhibitory effect on a variety of pathogens. It is a green biological pesticide.

[0023] Environmentally friendly and sustainable: The reuse of biogas slurry as agricultural waste can not only reduce environmental pollution, but also achieve sustainable utilization of resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Other features, objects and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0025] Figure 1 This is a schematic diagram of the comparison of experimental strawberry plant heights;

[0026] Figure 2 This is a schematic diagram for comparing the thickness of experimental strawberry stems. DETAILED DESCRIPTION

[0027] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0028] The Bacillus subtilis used in the following embodiments is purchased from the China Industrial Microbiological Culture Collection Center, and the Bacillus subtilis strain collection number is CICC No.10089.

[0029] The deposit number of Bacillus licheniformis strain is CICC No.20514.

[0030] The biogas slurry is liquid conventionally extracted from a biogas slurry tank.

[0031] In the following embodiments, before inoculating Bacillus subtilis and Bacillus licheniformis, Bacillus subtilis and Bacillus licheniformis need to be activated, wherein the activation method of Bacillus subtilis includes but is not limited to:

[0032] 1. Brown sugar water activation method (preferred method of this application):

[0033] Dissolve an appropriate amount of brown sugar in hot water and wait for it to cool to around 30-40℃.

[0034] Add Bacillus subtilis powder and mix well.

[0035] Place it in a warm, dark place and let it sit for 1-4 hours to allow the Bacillus subtilis to fully activate.

[0036] During the activation process, appropriate stirring can be performed to ensure that the bacteria are evenly distributed.

[0037] 2. Rice bran or wheat bran activation method:

[0038] Moisten the rice bran or bran with water and adjust the humidity to a suitable level.

[0039] Add Bacillus subtilis powder and stir thoroughly.

[0040] Place it in a warm and ventilated place, maintain a certain humidity and temperature, and let it stand for about half a day until the bacteria are activated.

[0041] 3. Other methods:

[0042] You can also use nutrient broth, yeast extract solution and other culture media for activation. The specific method is similar, that is, Bacillus subtilis is inoculated into the culture medium, cultured at 30-40°C for 1-4 hours, and stored for 24 hours to activate it; this application mainly uses 1 brown sugar water for activation.

[0043] The activation method of Bacillus licheniformis is:

[0044] 1. Take out the strain from the ultra-low temperature refrigerator:

[0045] Strains are usually stored as lyophilized powder or in the form of slants.

[0046] Under sterile conditions, use an inoculation loop or needle to inoculate the bacteria onto a suitable sterile culture medium, such as a slant culture medium.

[0047] 2. Constant temperature incubator activation:

[0048] Place the inoculated slant in a constant temperature incubator set at about 37°C.

[0049] The culture time is generally 24 hours, allowing the bacteria to recover from a dormant state to an actively growing state.

[0050] 3. Liquid culture medium expansion culture (preferred method of this application):

[0051] In cases where a large amount of bacterial liquid is required, the activated bacteria on the slant can be transferred to a liquid culture medium containing a carbon source such as brown sugar and necessary nutrients.

[0052] Expand the culture at an appropriate temperature and time while ensuring adequate oxygen supply.

[0053] The following is a detailed description of a strawberry-specific biofertilizer based on biogas slurry, which is made from the following raw materials in parts by weight: 40 parts of biogas slurry, 2 parts of potassium dihydrogen phosphate, 0.1 parts of potassium hydrogen phosphate, 0.05 parts of sulfate, 5 parts of molasses, 0.5 parts of Bacillus subtilis, and 0.5 parts of Bacillus licheniformis.

[0054] The biogas slurry is the residue after the biogas slurry is subjected to anaerobic fermentation for one month, and is the filtrate after filtering and removing solid impurities.

[0055] The filtration refers to screening the biogas slurry through a 35-mesh filter.

[0056] The sulfate is potassium sulfate.

[0057] The molasses comprises dry molasses powder, wherein the water content of the molasses is less than 20%.

[0058] Also included is a method for preparing a special strawberry biofertilizer, which is prepared by using the special strawberry biofertilizer prepared by the above technical solution, specifically comprising: S1: filtering and pre-treating 40 portions of the biogas slurry to obtain filtered biogas slurry;

[0059] S2: adding 2 parts of potassium dihydrogen phosphate, 0.1 parts of dipotassium hydrogen phosphate, and 0.05 parts of sulfate in the filtered biogas slurry in order according to the formula to obtain acidic biogas slurry;

[0060] S3: adding 5 parts of molasses to the acidic biogas slurry, inoculating 0.5 parts of Bacillus subtilis and 0.5 parts of Bacillus licheniformis at the same time, and stirring evenly to obtain a product to be fermented;

[0061] S4: The fermented material is fermented at 21° C. in an open environment for 3 days to obtain a biological fertilizer specifically for strawberries.

[0062] The pH value of the acidic biogas slurry is 6-6.5.

[0063] The EC value of the acidic biogas slurry is 5-10S / m.

[0064] The bacterial density of the strawberry-specific biological fertilizer is ≥1*10^6 cfu / ml.

[0065] Embodiment 2:

[0066] The filtration refers to screening the biogas slurry through a 35-mesh filter.

[0067] The sulfate is potassium sulfate.

[0068] The molasses comprises dry molasses powder, wherein the water content of the molasses is less than 20%.

[0069] A method for preparing a biological fertilizer for strawberries, which is prepared by using the biological fertilizer for strawberries prepared by the above technical solution, specifically comprising: S1: filtering and pre-treating 1 portion of the biogas slurry to obtain filtered biogas slurry;

[0070] S2: adding 0.1 parts of potassium dihydrogen phosphate, 0.1 parts of dipotassium hydrogen phosphate, and 0.01 parts of sulfate in order according to the formula amount to obtain acidic biogas slurry;

[0071] S3: adding 1 part of molasses to the acidic biogas slurry, inoculating 0.1 parts of Bacillus subtilis and 0.1 parts of Bacillus licheniformis at the same time, and stirring evenly to obtain a product to be fermented;

[0072] S4: The fermented material is fermented at 16° C. in an open environment for 2 days to obtain a biological fertilizer specifically for strawberries.

[0073] The pH value of the acidic biogas slurry is 6-6.5.

[0074] The EC value of the acidic biogas slurry is 5-10S / m.

[0075] The bacterial density of the strawberry-specific biological fertilizer is ≥1*10^6 cfu / ml.

[0076] Embodiment 3:

[0077] The filtering refers to screening the biogas slurry through an 80-mesh filter.

[0078] The sulfate is ammonium sulfate.

[0079] The molasses comprises dry molasses powder, wherein the water content of the molasses is less than 20%.

[0080] Also included is a method for preparing a special strawberry biofertilizer, which is prepared by using the special strawberry biofertilizer prepared by the above technical solution, specifically comprising: S1: filtering and pre-treating 60 portions of the biogas slurry to obtain filtered biogas slurry;

[0081] S2: adding 2 parts of potassium dihydrogen phosphate, 0.1 parts of dipotassium hydrogen phosphate, and 0.05 parts of sulfate in the filtered biogas slurry in order according to the formula to obtain acidic biogas slurry;

[0082] S3: adding 5 parts of molasses to the acidic biogas slurry, inoculating 0.5 parts of Bacillus subtilis and 0.5 parts of Bacillus licheniformis at the same time, and stirring evenly to obtain a product to be fermented;

[0083] S4: The fermented material is fermented at 21° C. in an open environment for 3 days to obtain a biological fertilizer specifically for strawberries.

[0084] The pH value of the acidic biogas slurry is 6-6.5.

[0085] The EC value of the acidic biogas slurry is 5-10S / m.

[0086] The bacterial density of the strawberry-specific biological fertilizer is ≥1*10^6 cfu / ml.

[0087] Embodiment 4:

[0088] The biogas slurry is the residue after the biogas slurry is subjected to anaerobic fermentation for one month, and is the filtrate after filtering and removing solid impurities.

[0089] The filtration refers to screening the biogas slurry through a 35-mesh filter.

[0090] The sulfate is ammonium sulfate.

[0091] The molasses comprises dry molasses powder, wherein the water content of the molasses is less than 20%.

[0092] Also included is a method for preparing a special strawberry biofertilizer, which is prepared by using the special strawberry biofertilizer prepared by the above technical solution, specifically comprising: S1: filtering and pre-treating 80 portions of the biogas slurry to obtain filtered biogas slurry;

[0093] S2: adding 4 parts of potassium dihydrogen phosphate, 4 parts of dipotassium hydrogen phosphate and 0.08 parts of sulfate in the filtered biogas slurry in order according to the formula to obtain acidic biogas slurry;

[0094] S3: adding 15 parts of molasses to the acidic biogas slurry, and inoculating 1.5 parts of Bacillus subtilis and 1.5 parts of Bacillus licheniformis at the same time, and stirring evenly to obtain a product to be fermented;

[0095] S4: The fermented material is fermented at 30° C. in an open environment for 5 days to obtain a biological fertilizer specifically for strawberries.

[0096] The pH value of the acidic biogas slurry is 6-6.5.

[0097] The EC value of the acidic biogas slurry is 5-10S / m.

[0098] The bacterial density of the strawberry-specific biological fertilizer is ≥1*10^6 cfu / ml.

[0099] According to the strawberry-specific biological fertilizer prepared in the above-mentioned embodiments 1-4, the present application also includes a method of using the same, adding 10-100L of the prepared strawberry-specific biological fertilizer into 10-100L of water per cubic meter of water, so that the EC value is less than 1.6S / m, and fertilizing through the drip irrigation pipe.

[0100] Using the strawberry-specific biological fertilizer prepared in Example 4 and the above-mentioned method of use, the applicant conducted a strawberry cultivation comparative test:

[0101] The experimental strawberry variety was Hongyan (Shuofeng. It was bred by the Horticulture Research Institute of Jiangsu Academy of Agricultural Sciences from the hybrid combination of MDUS 4484×MDUS4493). The control fertilizer was a mixture of a large number of element water-soluble fertilizer, Fushu seaweed high potassium and high calcium fertilizer, and NF300 biological organic fertilizer. The test fertilizer was a self-developed strawberry bacterial fertilizer.

[0102] The test sites were: strawberry picking greenhouses in Beilangzhong Village, Shunyi District, Beijing (No. 32, No. 29, No. 1, No. 3), strawberry plantation in Qubeiying Village (No. 4 bacterial fertilizer shed, sterile fertilizer shed), strawberry picking garden in Xingshou Town, Changping District, Beijing (No. 303, No. 304), and strawberry picking garden of Aojinhe Agricultural Development Co., Ltd., Shunyi District, Beijing (C-01, C-15). The soil fertility of the plots in the greenhouses was uniform and flat, and the greenhouses using the control fertilizer and the bacterial fertilizer had the same site size, temperature in the greenhouse, and light intensity.

[0103] Six sampling points were randomly selected from the control shed and the treatment shed respectively, and 10 strawberry plants were randomly selected from each sampling point, with a total of 60 strawberry plants to investigate the plant height and stem thickness; 10 strawberry plants were randomly selected to test the horizontal diameter, vertical diameter, fruit sweetness and fruit weight of the strawberry fruit; 3 strawberry plants were randomly selected to test the root length, dry weight and fresh weight of the whole strawberry plant.

[0104] Plant height: Use a ruler to measure the natural height from the ground to the tallest leaf

[0105] Stem diameter: Use a vernier caliper to measure the plant diameter at the middle of the main stem.

[0106] Fruit sweetness: Squeeze strawberry fruit into juice and measure with a digital refractometer

[0107] Strawberry dry weight: Dry in a dryer at 105℃ for 1-2 hours, then continue drying at 60℃ until constant weight is reached

[0108] Test results analysis

[0109] Effects of different treatments on growth characteristics of strawberry plants

[0110] The analysis of the growth of the aboveground part of strawberry plants showed that the effects of different treatments on the height and stem diameter of strawberry plants were not very different, but all had different degrees of promoting effects ( Figure 1 , Figure 2 ), the average plant height of greenhouse No. 1 where bacterial fertilizer was applied was 20.2 cm, and the average stem diameter was 3.7 mm, both of which were higher than those of the control group No. 3 greenhouse without sterile fertilizer. The average dry weight and fresh weight of strawberry plants that were applied with bacterial fertilizer were also higher than those of the control group that was not applied with bacterial fertilizer to varying degrees. This result shows that bacterial fertilizer treatment of strawberry plants can promote plant health and growth.

[0111] Analysis of the underground growth of strawberry plants (Table 1) showed that both bacterial fertilizer and other control fertilizers promoted root growth. The longest root length of strawberries in shed 32, where bacterial fertilizer was applied, was 24.33 cm.

[0112] Effects of different treatments on strawberry fruit characteristics

[0113] Analysis of strawberry fruit traits (Table 2) showed that different treatments had some effects on strawberry fruit diameter, longitudinal diameter and fruit weight. In the statistics of strawberry fruit data from 8 greenhouses in 4 groups, the fruit weight of strawberry fruits in the greenhouses where bacterial fertilizer was applied was slightly higher than that in the control greenhouses where bacterial fertilizer was not applied, with an average fruit weight of up to 21.7g and a single fruit weight of up to 39.40g.

[0114] The analysis of the flavor quality of strawberry fruit (Table 1) showed that the sweetness of strawberry fruit treated with bacterial fertilizer was higher than that of the control group without bacterial fertilizer. The highest average sweetness was 12.51% in fertilizer shed No. 32, and the highest sweetness of a single fruit was 14.3%, indicating that the application of bacterial fertilizer can improve the flavor quality of the fruit.

[0115]

[0116]

[0117] Table 1 Data on dry weight, fresh weight and root length of strawberries under different treatments

[0118]

[0119]

[0120] Table 2 Data on the diameter, longitudinal diameter and fruit weight of strawberry fruits under different treatments

[0121]

[0122]

[0123] Table 3 Sweetness data of strawberry fruits under different treatments

[0124] To sum up, bio-fertilizer is a pollution-free biological fertilizer made by fermenting one or more beneficial bacteria species. It has advantages in improving soil environment, improving soil fertility, promoting crop growth and development, and improving crop quality.

[0125] In this study, after applying biological fertilizer, the average plant height of strawberries reached 20.2cm, the average stem diameter reached 3.7mm, the average sweetness of the fruit reached 14%, the average fresh weight of strawberry plants reached 61.08g, and the root length reached 24.33cm, all of which were higher than those of the control group that applied ordinary fertilizer. The results show that the application of bacterial fertilizer can promote the healthy growth of strawberries and improve the flavor quality of the fruit. There was no significant difference between the experimental group and the control group in terms of fruit diameter, longitudinal diameter and fruit weight. The maximum average fruit weight was 23.41g, which was only 1.01g different from the control group.

[0126] The application of biological fertilizer increased the height of strawberry plants, the thickness of stems, and the sweetness of fruits, making the strawberries grow strong and having good fruit quality. The main reason may be that biological fertilizer can effectively increase the content of beneficial bacteria in the soil of the facility, achieving the effect of inhibiting bacteria with bacteria and treating bacteria with bacteria, effectively preventing the harm of pathogenic bacteria in the soil to the strawberry root system; at the same time, it is beneficial to the growth of strawberry roots, cultivating strong plants, and increasing the absorption and utilization of deep soil nutrients by strawberry plants. In addition, the application of biological fertilizer can improve the soil fertility level, reduce the application of chemical fertilizers, reduce the pollution of chemical fertilizers to soil and water sources, and enable strawberries to meet green and safe production standards. Therefore, biological fertilizer is suitable for promotion and use in strawberry production.

[0127] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A biological fertilizer for strawberries, characterized in that: The invention comprises the following raw materials in parts by weight: 1-100 parts of biogas slurry, 0.1-5 parts of potassium dihydrogen phosphate, 0.1-5 parts of dipotassium hydrogen phosphate, 0.01-0.1 parts of sulfate, 1-20 parts of molasses, 0.1-2 parts of Bacillus subtilis and 0.1-2 parts of Bacillus licheniformis.

2. The strawberry-specific biological fertilizer according to claim 1, characterized in that: The biogas slurry is the residue after the biogas slurry is subjected to anaerobic fermentation for one month, and is the filtrate after filtering and removing solid impurities.

3. The strawberry-specific biological fertilizer according to claim 2, characterized in that: The filtering refers to screening the biogas slurry through a 35-150 mesh filter.

4. The strawberry-specific biological fertilizer according to claim 1, characterized in that: The sulfate is any one of potassium sulfate or ammonium sulfate.

5. The strawberry-specific biological fertilizer according to claim 3, characterized in that: The molasses comprises dry molasses powder, wherein the water content of the molasses is less than 20%.

6. The method for preparing a biological fertilizer for strawberry as claimed in claims 1-5, characterized in that: S1: filtering and pretreating 1 to 100 portions of the biogas slurry to obtain filtered biogas slurry; S2: adding 0.1-5 parts of potassium dihydrogen phosphate, 0.1-5 parts of dipotassium hydrogen phosphate, and 0.01-0.1 parts of sulfate to the filtered biogas slurry in order according to the formula to obtain acidic biogas slurry; S3: adding 1-20 parts of molasses to the acidic biogas slurry, inoculating 0.1-2 parts of Bacillus subtilis and 0.1-2 parts of Bacillus licheniformis at the same time, and stirring evenly to obtain a product to be fermented; S4: The fermented material is fermented at 16° C.-30° C. for 2-5 days to obtain a biological fertilizer specifically for strawberries.

7. A strawberry-specific biological fertilizer and a preparation method thereof as claimed in claim 6, characterized in that: The pH value of the acidic biogas slurry is 6-6.

5.

8. A strawberry-specific biological fertilizer and a preparation method thereof as claimed in claim 7, characterized in that: The EC value of the acidic biogas slurry is 5-10S / m.

9. A strawberry-specific biological fertilizer and a preparation method thereof as claimed in claim 7, characterized in that: The bacterial density of the strawberry-specific biological fertilizer is ≥1*10^6 cfu / ml.

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