Bacillus megaterium HP-3 and its application

Abstract

The present application relates to the field of microorganisms, and specifically discloses a Bacillus megaterium HP‑3 and an application thereof; a Bacillus megaterium HP‑3, Bacillus megaterium HP‑3 (Bacillus megaterium HP‑3) is deposited in the China Center for Type Culture Collection, with a deposit number of CCTCCNO.M20221791; application: a biological fertilizer, comprising the following raw materials in parts by weight: potassium phosphate, diammonium phosphate, EDTA chelated calcium, EDTA chelated iron, magnesium sulfate, zinc sulfate, humic acid, plant fiber, porous particles, and Bacillus megaterium HP‑3 bacterial liquid; Bacillus megaterium HP‑3 has the advantages of strong environmental tolerance, high temperature resistance, and ultraviolet resistance, and the prepared biological fertilizer can inhibit diseases and promote the growth of crops and vegetables.

Description

Technical Field

[0001] The present application relates to the field of microorganisms, and more specifically, to Bacillus megaterium HP-3 and its application. Background Art

[0002] Bacillus megaterium is a Gram-positive bacterium belonging to the genus Bacillus. It is short rod-shaped, with a single diameter of 2.5 to 3.0 microns and a length of more than 20 microns. It is characterized by the ability to form endogenous spores. This bacterium is widely distributed in nature and is commonly found in soil, water, air, and the body surface and intestines of animals and plants. Bacillus megaterium can be used to produce enzymes, antibiotics, biological control agents, and biological fertilizers.

[0003] When Bacillus megaterium is used as a biological fertilizer, it can effectively alleviate fruit tree diseases, vegetable diseases, grain diseases, cotton diseases, etc., increase the yield of fruits, vegetables and grains, and reduce the use of chemical pesticides, avoiding harm to the environment and human health.

[0004] However, Bacillus megaterium is highly dependent on environmental conditions. If the conditions are not suitable, its growth rate will slow down or even die, thus affecting the fertilizer efficiency of the bio-fertilizer. Moreover, during the storage and transportation of bio-fertilizer, the survival rate of Bacillus megaterium may be affected by high temperature, dryness, ultraviolet rays, etc., affecting the number of effective live bacteria in the bio-fertilizer and thus affecting the use effect of the bio-fertilizer.

[0005] Therefore, how to obtain a new Bacillus megaterium with strong environmental tolerance and not easily affected by external high temperature, ultraviolet rays, etc., so that the survival rate and activity of Bacillus megaterium can be affected, and the obtained biological fertilizer can prevent and control diseases while increasing the yield of fruits, vegetables and crops. Summary of the invention

[0006] In order to obtain a new Bacillus megaterium with strong environmental tolerance and not easily affected by external high temperature, ultraviolet rays and the like, the survival rate and activity of Bacillus megaterium can be affected, and the prepared biological fertilizer can prevent and control diseases while increasing the yield of fruits, vegetables and crops. The present application provides a Bacillus megaterium HP-3 and its application.

[0007] In a first aspect, the present application provides a Bacillus megaterium HP-3, which adopts the following technical solution:

[0008] A Bacillus megaterium HP-3, Bacillus megaterium HP-3 (Bacillus megaterium HP-3) is deposited in China Center for Type Culture Collection, with the deposit number: CCTCCNO.M20221791.

[0009] By adopting the above technical scheme, Bacillus megaterium HP-3 has the advantages of good high temperature resistance and ultraviolet resistance. During the preparation, transportation and storage process, the effective live bacteria number of Bacillus megaterium HP-3 is not easily affected by external environmental factors. When Bacillus megaterium is added to the biological fertilizer as a raw material, the biological fertilizer can prevent and control diseases while increasing the yield of fruits, vegetables and crops.

[0010] In a second aspect, the present application provides a biofertilizer, which adopts the following technical solution:

[0011] A biological fertilizer comprises the following raw materials in parts by weight:

[0012] 20-30 parts of potassium phosphate, 20-30 parts of ammonium dihydrogen phosphate, 0.0001-0.0005 parts of EDTA chelated calcium, 0.0001-0.0003 parts of EDTA chelated iron, 0.001-0.0015 parts of magnesium sulfate, 0.0001-0.0008 parts of zinc sulfate, 0.1-0.25 parts of humic acid, 1-3 parts of plant fiber, 1-5 parts of porous particles, and 35-50 parts of Bacillus megaterium HP-3 bacterial liquid.

[0013] By adopting the above technical scheme, the biofertilizer has sufficient potassium source, calcium source, nitrogen source, carbon source and other substances, and utilizes the adsorption loading effect of plant fiber and porous particles, so that Bacillus megaterium HP-3 can resist the high humidity erosion of external rain water, and ensure that Bacillus megaterium HP-3 adheres to the soil surface; and utilizes the porous structure of plant fiber and porous particles to further improve the high temperature resistance and ultraviolet resistance of Bacillus megaterium HP-3 in the soil through the heat insulation effect, and combined with the high temperature resistance and ultraviolet resistance of the screened Bacillus megaterium HP-3, the Bacillus megaterium HP-3 in the biofertilizer can play a role for a long time, and is not easily affected by high temperature and ultraviolet rays, resulting in the activity being affected.

[0014] Preferably, the preparation method of the Bacillus megaterium HP-3 bacterial liquid is as follows:

[0015] Inoculate Bacillus megaterium HP-3 into PDA solid culture medium, and culture for 8-12 hours at 28-32° C. and pH 6.5-7.5 to obtain activated bacteria;

[0016] The activated bacteria were transferred to LB liquid culture medium at an inoculation rate of 4-8%, cultured at 28-32° C. and 110-150 rpm for 5-8 days, and centrifuged to remove the supernatant to obtain a bacterial solution.

[0017] By adopting the above technical scheme, the bacterial liquid obtained after activation and expansion culture not only has a high bacterial content, but also has high bacterial activity, and at the same time has good high temperature resistance and ultraviolet resistance. During transportation and storage, the bacterial activity and content are not easily affected, so that Bacillus megaterium HP-3 can play a role in the soil efficiently and increase the yield of fruits, vegetables and crops.

[0018] Preferably, the plant fiber is made of coconut shell fiber, inulin and carboxymethyl cellulose solution in a mass ratio of 1:0.5-1:0.1-0.3.

[0019] By adopting the above technical scheme, coconut shell fiber, inulin and carboxymethyl cellulose solution are matched, and the viscosity of the carboxymethyl cellulose solution is utilized to facilitate the adhesion of inulin to the surface of coconut shell fiber, and the water absorption and hydrophilicity of inulin and coconut shell fiber are utilized to facilitate the adsorption of Bacillus megaterium HP-3 on the surface of plant fiber.

[0020] The combination of coconut shell fiber and inulin utilizes the porosity of coconut shell fiber, which can not only insulate, but also reflect and isolate ultraviolet rays. Combined with the adsorption effect of coconut shell fiber on Bacillus megaterium HP-3, it can further improve the high temperature resistance and ultraviolet resistance of Bacillus megaterium HP-3, and increase Bacillus megaterium HP-3's tolerance to the external environment; combined with the multi-molecular fructose in the surface inulin, it can provide nutrients for the growth and reproduction of Bacillus megaterium HP-3, thereby promoting the growth and reproduction of Bacillus megaterium HP-3 in the soil, prolonging the effect of Bacillus megaterium HP-3 in the soil, and increasing the yield of fruits, vegetables and crops.

[0021] Preferably, the porous particles are composed of ceramsite and biochar in a mass ratio of 1:1-2.

[0022] Preferably, the average particle size of the ceramsite and biochar is 1-3 mm.

[0023] By adopting the above technical solution, ceramsite and biochar are combined, and the porous adsorption effect of ceramsite and biochar is utilized to facilitate the adsorption of Bacillus megaterium HP-3; the density of ceramsite is about 0.9-1.4g / cm 3 The biochar density is about 0.45-1.1g / cm 3Therefore, ceramsite is lighter than biochar. Ceramsite adsorbs and carries Bacillus megaterium HP-3 close to the upper surface of the soil, while biochar easily carries Bacillus megaterium HP-3 below the ceramsite in the soil. The hierarchical porous permeability of ceramsite and biochar increases the air permeability and water retention of the soil. The porous structure of ceramsite and biochar can provide Bacillus megaterium with the air and moisture required for growth, ensuring the growth of Bacillus megaterium. The heat insulation and refraction effects of the porous structure are used to further improve the high temperature resistance and ultraviolet resistance of Bacillus megaterium HP-3, so that Bacillus megaterium has the advantage of long-term effect on the soil, which is helpful for the transformation of organic matter and the release of nutrients in the soil, promotes the growth of fruits, vegetables, crops, etc., and increases their yield.

[0024] Preferably, the PDA solid culture medium comprises 180-220 g / L of potato, 10-15 g / L of glucose, 5-10 g / L of sucrose, 15-20 g / L of agar, and the balance of water.

[0025] By adopting the above technical scheme, the high-content carbon source and nitrogen source contained in substances such as potato extract, glucose, and agar in the PDA culture medium are utilized to provide the nutrient elements and vitamins required for the growth of Bacillus megaterium HP-3, thereby activating Bacillus megaterium.

[0026] Preferably, the LB liquid culture medium comprises 8-15 g / L of tryptone, 2-6 g / L of yeast extract, 8-12 g / L of sodium chloride, and the balance water.

[0027] By adopting the above technical scheme, LB medium uses substances such as tryptone and yeast extract to provide Bacillus megaterium HP-3 with rich carbon sources, nitrogen sources and minerals, as well as amino acids and vitamins required for growth, so as to expand the culture of Bacillus megaterium HP-3. On the LB medium, Bacillus megaterium can grow better and form obvious colonies.

[0028] In summary, this application has the following beneficial effects:

[0029] 1. Bacillus megaterium HP-3 has the advantages of good resistance to high temperature and ultraviolet rays. During the preparation, transportation and storage process, the effective number of live bacteria of Bacillus megaterium HP-3 is not easily affected by external environmental factors. When Bacillus megaterium is added to biological fertilizer as a raw material, the biological fertilizer can prevent and control diseases while increasing the yield of fruits, vegetables and crops.

[0030] 2. The biofertilizer is supplemented with potassium source, calcium source, nitrogen source, carbon source and other substances, and the porous structure of plant fiber and porous particles is used to further improve the high temperature resistance and ultraviolet resistance of Bacillus megaterium HP-3 in the soil through heat insulation. Combined with the high temperature resistance and ultraviolet resistance of the screened Bacillus megaterium HP-3, the Bacillus megaterium HP-3 in the biofertilizer can function for a long time and is not easily affected by high temperature and ultraviolet rays, which may affect its activity.

[0031] 3. The combination of coconut shell fiber and inulin can utilize the porosity of coconut shell fiber to not only insulate, but also reflect and isolate ultraviolet rays. Combined with the adsorption effect of coconut shell fiber on Bacillus megaterium HP-3, it can further improve the high temperature resistance and ultraviolet resistance of Bacillus megaterium HP-3, and increase Bacillus megaterium's tolerance to the external environment; combined with the multi-molecular fructose in the surface inulin, it can provide nutrients for the growth and reproduction of Bacillus megaterium, thereby promoting the growth and reproduction of Bacillus megaterium HP-3 in the soil, prolonging the effect of Bacillus megaterium HP-3 in the soil, and increasing the yield of fruits, vegetables and crops. DETAILED DESCRIPTION

[0032] The present application is further described in detail below with reference to the embodiments.

[0033] Example

[0034] Example 1: Isolation and screening of Bacillus megaterium:

[0035] (1) Test soil: Soil was collected from an orchard in Laoshan, Qingdao. The sampling site was a place where fruit trees had been planted for more than ten years. The collected soil was mixed, crushed, and weeds, stones, tree roots and other debris were removed. The soil was mixed evenly and placed in an ice bucket at 4°C for future use. The basic physical and chemical properties of the test soil are shown in Table 1.

[0036] Table 1 Physical and chemical properties of the tested soils

[0037]

[0038] (2) Culture medium:

[0039] Beef extract peptone medium: 10g peptone, 5g sodium chloride, 4g beef extract, 1000mL deionized water, pH 7.4; LB liquid medium: 10g sodium chloride, 4g yeast powder, 15g tryptone, 12g agar, 1000mL deionized water, pH 7.5.

[0040] (3) Isolation and screening of Bacillus megaterium strains: Weigh 10 g of the test soil sample, add 90 mL of sterile water, and shake at 30 °C and 116 r / min for 2 h to form a suspension. The suspension is diluted by gradient dilution to make 10 -1, 10 -2 , 10 -3 , 10 -4 , 10 -5 , 10 -6 , 10 -7 times the dilution, take 10 μL of the dilutions of different gradients and evenly spread them on beef extract peptone medium, do three parallel replicates for each gradient, culture at 30°C for 3 days, select strains with fast growth or transparent circles around them, use the streak method to separate and purify them in the medium, and set aside to obtain the primary screening strains; inoculate the primary screening strains into LB liquid medium, and culture them on a shaking table at 30°C and 180 r / min for 1 day to obtain the screening strains;

[0041] (4) Purification: purify and preserve the screened strains;

[0042] The purified strain was named Bacillus megaterium HP-3 and was deposited in the China Center for Type Culture Collection on November 14, 2022 with the accession number CCTCC No. M20221791 and the classification name Bacillus megaterium HP-3.

[0043] Identification of Bacillus megaterium HP-3:

[0044] (1) Bacterial and colony morphology: The screened strains were subjected to Gram staining, capsule staining, and spore staining, and the bacterial morphology was observed under a microscope.

[0045] Bacillus megaterium HP-3 is a short rod-shaped, Gram-positive bacterium with spores. The spores are oval, blunt at both ends, and motile. The colonies formed on beef extract peptone medium are round, milky white, about 2 to 3 mm in diameter, with neat edges, flat and moist.

[0046] (2) Antagonistic characteristics:

[0047] ① Gelatin liquefaction: Take gelatin culture medium and inoculate Bacillus megaterium HP-3 by puncture inoculation method, and use no inoculation as blank control. After culturing at 37℃ for 48h, gently put the gelatin culture medium into a 4℃ refrigerator for 30min, and observe the changes of gelatin. The liquefaction indicates that Bacillus megaterium HP-3 can produce extracellular enzymes of gelatinase; the experimental results show that the gelatin inoculated with Bacillus megaterium HP-3 did not liquefy, indicating that Bacillus megaterium HP-3 does not produce extracellular enzymes of gelatinase;

[0048] ② Starch hydrolysis experiment: Bacillus megaterium HP-3 was inoculated on starch plate culture medium and cultured at 30℃ for 48h. Iodine solution was dripped directly on the culture surface to see if it turned blue to determine whether amylase was produced; if the experimental result showed blue, it indicated that Bacillus megaterium HP-3 produced starch hydrolyzing enzyme;

[0049] ③ Catalase test: The purified strain was cultured in a liquid culture medium containing 5g beef extract, 5g peptone, 5g sodium chloride and 1L water at a speed of 116rpm, a temperature of 30°C and a pH value of 7.5 for 12h to obtain a strain culture solution; 3% hydrogen peroxide was added dropwise to the strain culture solution, and the result showed that a large number of bubbles were generated, which was a positive reaction, indicating that Bacillus megaterium HP-3 contained catalase;

[0050] ④Sugar fermentation experiment: weigh 0.5g glucose, 0.5g peptone, and K 2 HPO 4 0.5g of Bacillus megaterium and 100ml of water were used to prepare peptone culture medium. 1% bromothymol blue was added and mixed. The culture solution was dispensed into test tubes with a height of about 4cm. A Dulbecco's tube was inverted in the tube to fill it with the culture solution. The tube was sterilized at 115℃ for 20min. The Bacillus megaterium HP-3 strain that had been cultured for 10h was inoculated into the culture medium with a puncture needle. After culturing at room temperature for 1d, 3d and 5d, the color turned yellow and bubbles were generated, which was a positive reaction, indicating that the sugar could be fermented and utilized.

[0051] Application and preparation examples of plant fibers

[0052] Application preparation example 1: Plant fiber is prepared by the following method:

[0053] 0.2 kg of carboxymethyl cellulose solution is uniformly sprayed on the surface of 1 kg of coconut shell fiber, the average length of the coconut shell fiber is 3 mm, and the carboxymethyl cellulose solution is a 1% by mass sodium carboxymethyl cellulose aqueous solution; then 0.8 kg of inulin is added, the inulin is sieved through an 80-mesh sieve, and the inulin is added at a speed of 120 g / min. During the adding process, the coconut shell fiber is stirred at a speed of 200 r / min. After being evenly mixed, it is dried and dispersed until the coconut shell fibers are not adhered to each other and agglomerated, so as to obtain a finished plant fiber.

[0054] Application Preparation Example 2: This preparation example differs from Preparation Example 1 in that:

[0055] 0.1 kg of carboxymethyl cellulose solution is uniformly sprayed on the surface of 1 kg of coconut shell fiber, the average length of the coconut shell fiber is 3 mm, and the carboxymethyl cellulose solution is a 1% by mass sodium carboxymethyl cellulose aqueous solution; then 0.5 kg of inulin is added, the inulin is sieved through an 80-mesh sieve, and the inulin is added at a speed of 120 g / min. During the adding process, the coconut shell fiber is stirred at a speed of 200 r / min. After being evenly mixed, it is dried and dispersed until the coconut shell fibers are not adhered to each other and agglomerated, so as to obtain a finished plant fiber.

[0056] Application Preparation Example 3: This preparation example differs from Preparation Example 1 in that:

[0057] 0.3 kg of carboxymethyl cellulose solution is uniformly sprayed on the surface of 1 kg of coconut shell fiber, the average length of the coconut shell fiber is 3 mm, and the carboxymethyl cellulose solution is a 1% by mass sodium carboxymethyl cellulose aqueous solution; then 1 kg of inulin is added, the inulin is sieved through an 80-mesh sieve, and the inulin is added at a speed of 120 g / min. During the adding process, the coconut shell fiber is stirred at a speed of 200 r / min. After being evenly mixed, it is dried and dispersed until the coconut shell fibers are not adhered to each other and agglomerated, so as to obtain a finished plant fiber.

[0058] Application and preparation example of Bacillus megaterium liquid

[0059] Application Preparation Example 4: Bacillus megaterium liquid was prepared by the following method:

[0060] Weigh 200 g / L of potatoes, 12 g / L of glucose, 8 g / L of sucrose, 18 g / L of agar, and the balance of water; peel and cut the potatoes into pieces, put them into a pot, add 1000 mL of water, boil and keep for 30 min, then filter with gauze, and make up the filtrate to 1000 mL with water to obtain potato filtrate; add mashed agar to the filtrate, heat to 60°C, stir continuously until the agar is completely dissolved, adjust the pH to 5.8 with HCL or NaOH, package and seal, sterilize at 121°C for 25 min, and let stand to cool to obtain PDA solid culture medium;

[0061] Weigh 12 g / L of tryptone, 4 g / L of yeast extract, 10 g / L of sodium chloride, and the balance of water; weigh tryptone, yeast extract, and sodium chloride, mix them, add 800 mL of water, stir until they are completely dissolved, then add NaOH to adjust the pH to 7.0, add water to make the volume to 1000 mL, then package, seal, and wrap, sterilize at 121°C for 25 min, and cool to obtain LB liquid culture medium;

[0062] The Bacillus megaterium HP-3 of Example 1 was inoculated into a PDA solid culture medium at an inoculum rate of 5%, and cultured at 30° C. and pH 7.0 for 10 h to obtain activated bacteria;

[0063] The activated bacteria were transferred to LB liquid culture medium at a 6% inoculation rate and cultured at 30°C and 130 rpm for 7 days. The supernatant was removed after centrifugation to obtain a bacterial solution. The average content of effective bacterial cells in the bacterial solution was 4.52×10 9 cfu / mL.

[0064] Application Preparation Example 5: This Preparation Example differs from Preparation Example 4 in that:

[0065] Weigh 180 g / L of potatoes, 15 g / L of glucose, 5 g / L of sucrose, 20 g / L of agar, and the balance of water; peel and cut the potatoes into pieces, put them into a pot, add 1000 mL of water, boil and keep for 30 minutes, then filter with gauze, and make up the filtrate to 1000 mL with water to obtain potato filtrate; add mashed agar to the filtrate, heat to 60°C, stir continuously until the agar is completely dissolved, adjust the pH to 5.8 with HCL or NaOH, package and seal, sterilize at 121°C for 25 minutes, and let stand to cool to obtain PDA solid culture medium;

[0066] Weigh 8 g / L of tryptone, 6 g / L of yeast extract, 8 g / L of sodium chloride, and the balance of water; weigh tryptone, yeast extract and sodium chloride, mix them, add 800 mL of water, stir until they are completely dissolved, then add NaOH to adjust the pH to 7.0, add water to make the volume to 1000 mL, then package, seal, and wrap, sterilize at 121°C for 25 min, and cool to obtain LB liquid culture medium;

[0067] Bacillus megaterium HP-3 was inoculated into PDA solid culture medium at an inoculum rate of 5%, and cultured at 28° C. and pH 6.5 for 12 h to obtain activated bacteria;

[0068] The activated bacteria were transferred to LB liquid culture medium at an inoculation rate of 4%, cultured at 28° C. and 110 rpm for 8 days, and centrifuged to remove the supernatant to obtain a bacterial liquid.

[0069] Application Preparation Example 6: This Preparation Example differs from Preparation Example 4 in that:

[0070] Weigh 220 g / L of potatoes, 10 g / L of glucose, 10 g / L of sucrose, 15 g / L of agar, and the balance of water; peel and cut the potatoes into pieces, put them into a pot, add 1000 mL of water, boil and keep for 30 minutes, then filter with gauze, and make up the filtrate to 1000 mL with water to obtain potato filtrate; add mashed agar to the filtrate, heat to 60°C, stir continuously until the agar is completely dissolved, adjust the pH to 5.8 with HCL or NaOH, package and seal, sterilize at 121°C for 25 minutes, and let stand to cool to obtain PDA solid culture medium;

[0071] Weigh 15 g / L of tryptone, 2 g / L of yeast extract, 12 g / L of sodium chloride, and the balance of water; weigh tryptone, yeast extract, and sodium chloride, mix them, add 800 mL of water, stir until they are completely dissolved, then add NaOH to adjust the pH to 7.0, add water to make the volume to 1000 mL, then package, seal, and wrap, sterilize at 121°C for 25 min, and cool to obtain LB liquid culture medium;

[0072] Inoculate Bacillus megaterium HP-3 at an inoculum rate of 5% into a PDA solid culture medium, and culture at 32° C. and pH 7.5 for 8 hours to obtain activated bacteria;

[0073] The activated bacteria were transferred to LB liquid culture medium at an inoculation rate of 8%, cultured at 32° C. and 150 rpm for 5 days, and centrifuged to remove the supernatant to obtain a bacterial liquid.

[0074] Application Examples

[0075] Application example 1: A biological fertilizer:

[0076] 25kg potassium phosphate, 25kg diammonium phosphate, 0.0003kg EDTA chelated calcium, 0.0002kg EDTA chelated iron, 0.0012kg magnesium sulfate, 0.0005kg zinc sulfate, 0.2kg humic acid, 2kg plant fiber, 3kg porous particles, 45kg Bacillus megaterium HP-3 bacterial liquid; the plant fiber is selected from the plant fiber prepared in Application Preparation Example 1, the porous particles are composed of ceramsite and biochar in a mass ratio of 1:1, the average particle size of the ceramsite and the biochar is 2mm, and the average porosity of the ceramsite and the biochar is 55%; the Bacillus megaterium HP-3 bacterial liquid is selected from the bacterial liquid prepared in Application Preparation Example 4.

[0077] Application Example 2: The difference between this application example and application example 1 is:

[0078] 20kg potassium phosphate, 20kg diammonium phosphate, 0.0001kg EDTA chelated calcium, 0.0001kg EDTA chelated iron, 0.001kg magnesium sulfate, 0.0001kg zinc sulfate, 0.1kg humic acid, 1kg plant fiber, 1kg porous particles, 35kg Bacillus megaterium HP-3 bacterial liquid; the plant fiber is selected from the plant fiber prepared in Application Preparation Example 2, the porous particles are composed of ceramsite and biochar in a mass ratio of 1:1, and the average particle size of the ceramsite and biochar is 1mm; the Bacillus megaterium HP-3 bacterial liquid is selected from the bacterial liquid prepared in Application Preparation Example 5.

[0079] Application Example 3: The difference between this application example and application example 1 is:

[0080] 30kg potassium phosphate, 30kg diammonium phosphate, 0.0005kg EDTA chelated calcium, 0.0003kg EDTA chelated iron, 0.0015kg magnesium sulfate, 0.0008kg zinc sulfate, 0.25kg humic acid, 3kg plant fiber, 5kg porous particles, 50kg Bacillus megaterium HP-3 bacterial liquid; the plant fiber is selected from the plant fiber prepared in Application Preparation Example 3, the porous particles are composed of ceramsite and biochar in a mass ratio of 1:2, and the average particle size of the ceramsite and biochar is 3mm; the Bacillus megaterium HP-3 bacterial liquid is selected from the bacterial liquid prepared in Application Preparation Example 6.

[0081] Performance testing

[0082] 1. High temperature resistance test

[0083] The Bacillus megaterium HP-3 bacterial solution prepared in Preparation Example 4 was placed at 80, 90, and 100° C. for 30 min, and the number of effective live bacteria in the bacterial solution was detected and calculated, and the data was recorded.

[0084] 2. UV resistance test

[0085] The Bacillus megaterium HP-3 bacterial solution prepared in Preparation Example 4 was irradiated under an ultraviolet lamp, which was a UV-B type ultraviolet lamp with a wavelength of 320nm. The irradiation was carried out for 30min, 45min, and 60min. The content of effective bacteria in the bacterial solution was detected and calculated, and the data was recorded.

[0086] Table 2 Performance test table

[0087]

[0088] This indicates that after high temperature and ultraviolet light treatment, the number of effective live bacteria in the bacterial solution tends to the initial effective live bacteria number, and Bacillus megaterium HP-3 has good resistance to high temperature and ultraviolet light.

[0089] 3. Disease prevention and control

[0090] The experimental fields are: Qingdao City, Shandong Province;

[0091] The 3 mu of land correspond to the biological fertilizers prepared in Application Examples 1-3 respectively.

[0092] Select rice of the same batch and variety that are grown normally, apply biofertilizer to the rice fields, and add 30kg of biofertilizer to 1 mu of land. After the rice is fully mature, observe the sheath blight rate and yield of rice in different test fields, and use rice without adding biofertilizer as a control, and record the data.

[0093] 4. Growth promotion detection

[0094] The experimental fields are: Qingdao City, Shandong Province;

[0095] The 3 mu of land correspond to the biological fertilizers prepared in Application Examples 1-3 respectively.

[0096] Select cabbages of the same batch and variety that are planted normally. After the cabbage seeds are germinated, transplant them into the land. Add 15kg of biofertilizer per acre of cabbage field. When the cabbage is harvested, observe the yield of cabbage in different test fields, and use rice without adding biofertilizer as a control, and record the data.

[0097] In the above experiments, except for the different biofertilizers, the other test conditions were the same, compounding the single variable principle.

[0098] Table 3 Performance test table

[0099] project Rice sheath blight rate / % Rice yield / kg / mu Cabbage yield / kg / mu Application Example 1 0 1010 1600 Application Example 2 2 970 1500 Application Example 3 1 1000 1550 Comparison 75 740 1000

[0100] Combined with the data in Table 3, it can be seen that biological fertilizers can not only inhibit pathogens, but also promote the growth of crops and vegetables, thereby increasing the yield of crops and vegetables.

[0101] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A Bacillus megaterium HP-3, characterized in that Bacillus megaterium HP-3 is deposited in China Center for Type Culture Collection with the deposit number: CCTCC NO.M 20221791.

2. A biological fertilizer, characterized in that: Contains the following raw materials in parts by weight: 20-30 parts of potassium phosphate, 20-30 parts of ammonium dihydrogen phosphate, 0.0001-0.0005 parts of EDTA chelated calcium, 0.0001-0.0003 parts of EDTA chelated iron, 0.001-0.0015 parts of magnesium sulfate, 0.0001-0.0008 parts of zinc sulfate, 0.1-0.25 parts of humic acid, 1-3 parts of plant fiber, 1-5 parts of porous particles, and 35-50 parts of Bacillus megaterium HP-3 bacterial liquid; the Bacillus megaterium bacterial liquid is prepared by the Bacillus megaterium HP-3 described in claim 1.

3. A biological fertilizer according to claim 2, characterized in that: The plant fiber is made of coconut shell fiber, inulin and carboxymethyl cellulose solution in a mass ratio of 1:0.5-1:0.1-0.

3.

4. A biological fertilizer according to claim 2, characterized in that: The porous particles are composed of ceramsite and biochar in a mass ratio of 1:1-2.

5. A biological fertilizer according to claim 4, characterized in that: The average particle size of the ceramsite and biochar is 1-3 mm.

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