Bacillus cereus and tea cake powder composition and use method

Abstract

The invention provides a method for preventing and controlling peanut leaf spot disease by using a Bacillus cereus and tea cake powder composition, and a Bacillus cereus aqueous solution and powder plus tea cake powder, which can effectively improve the effect of preventing and controlling peanut leaf spot disease. The tea cake powder is completely compatible with Bacillus cereus spores and has no effect on spore germination. The tea cake powder contains fat, protein, tea saponin and other ingredients, which can improve the wetting performance and adhesion performance of the Bacillus cereus aqueous solution and powder on the target when applied, and provide nutrients for the spore germination of Bacillus cereus. The attachment rate and infection rate of Bacillus cereus on the target disease are improved, thereby improving the prevention and control effect.

Description

Technical Field

[0001] The invention belongs to the field of killing agricultural pests, and specifically relates to a Bacillus cereus and tea cake powder composition and a use method thereof. Background Art

[0002] Bacillus SC is a pathogenic bacterium that has an inhibitory effect on plant fungal and bacterial diseases. It can be widely used in the prevention and control of plant diseases on roots, stems, leaves, flowers, and fruits and vegetables. Its metabolite indoleacetic acid can promote plant growth. Since Bacillus cereus has a good effect on the prevention and control of diseases and does not cause harm to the environment and human body, it has attracted more and more attention. At present, there are 10 registered pesticide varieties in China with Bacillus cereus as the active ingredient, which are used to prevent and control fungal and bacterial diseases of rice, tomatoes, watermelons, cucumbers, tobacco, strawberries, and other crops.

[0003] However, compared with chemical pesticides, Bacillus cereus has disadvantages such as a single dosage form, biological activity that is easily affected by the environment, and low work efficiency. There are risks such as spores being digested during production and storage or not fully germinating when used, resulting in low Bacillus cereus prevention efficacy and unstable effects. Tea cake powder contains 11-13% saponins, 11-17wt% crude protein, 5-7wt% crude fat, 3-5wt% minerals and 24-35wt% easily hydrolyzed polysaccharides. It is a natural surfactant with the characteristics of fast wetting speed and strong dispersion ability. It can improve the adhesion of spores on plants and increase the prevention effect of Bacillus against certain plant bacteria and fungal diseases.

[0004] Leaf spot is a general term for black spot, brown spot and net spot that occur on peanut leaves, petioles, stems, flowers and fruits. These three diseases can occur together on the same plant. When black spot and net spot occur seriously, the leaves will fall off prematurely or even the whole plant will die. The yield of peanuts generally decreases by 10-20% after being affected, and more than 30% in severe cases. Leaf spot is one of the main diseases of peanuts in my country and one of the reasons for the low yield of peanuts in my country. At present, chemical pesticides are used to prevent and control peanut leaf spot in China. Long-term use of chemical pesticides will lead to problems of drug resistance and pesticide residues.

[0005] There is a need in the art to develop a pesticide for peanut leaf spot disease that has good safety, avoids the development of drug resistance in the leaf spot disease, and has high preventive efficacy. Summary of the invention

[0006] The present invention relates to a Bacillus cereus and tea cake powder composition and a method of use. The Bacillus cereus of the present invention is isolated from the tea garden soil in Shucheng County, named Bacillus cereus, and was deposited in the General Microbiological Center of the China Microbiological Culture Collection Administration on July 27, 2023, at No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing, and the culture collection number is CGMCC NO.28028.

[0007] The strain was isolated and identified by the pharmacodynamics team of Anhui Hefei Gaoer Life Science Research Institute Co., Ltd. from the soil of the tea garden in Shucheng County. The specific sequencing results are as follows:

[0008] ITS sequence:

[0009]

[0010] Unless otherwise specified in the present invention, the Bacillus cereus is Bacillus cereus BcSc.

[0011] One of the purposes of this application is to provide a method for preventing and treating peanut leaf spot, comprising the following steps:

[0012] (1) Dispersing a Bacillus cereus aqueous solution, a powder and tea cake powder in water to obtain a sprayable agent; the dispersion ratio of the Bacillus cereus aqueous solution and the tea cake powder in water is such that the sprayable amount per mu of the composition of Bacillus cereus and tea cake powder aqueous solution is (a) 150-400 mL of Bacillus cereus + 200-400 g of tea cake powder, and the sprayable amount per mu of the powder is 40-60 g of Bacillus cereus + 250-350 g of tea cake powder.

[0013] (2) Spraying the sprayable agent on peanut seedlings in the field, preferably during the initial flowering period of the peanuts.

[0014] In the method for preventing and controlling peanut leaf spot disease provided in the present application, the spores produced by Bacillus cereus are used to germinate and invade into the peanut plant tissue to occupy a space, thereby preventing the leaf spot mycelium from infecting the plant. The tea cake powder contains fat, protein, tea saponin and other ingredients, which can improve the dispersibility of the Bacillus cereus in water and provide nutrients for the germination of Bacillus cereus spores.

[0015] It should be noted that in the art, high-concentration, high-purity tea saponin has an inhibitory effect on bacteria and fungi, while adding tea saponin and other saponin substances in the form of tea cake powder will not inhibit Bacillus cereus, but can improve the bactericidal activity of Bacillus cereus. This may be because, on the one hand, the concentration and purity of tea saponin are diluted by other substances in tea cake powder, reducing its inhibitory effect on Bacillus cereus; on the other hand, the protein, fat and other nutrients in tea cake powder provide a growth environment for Bacillus cereus, and also offset the inhibitory effect of saponin substances; thirdly, saponin substances increase the dispersibility, improve the uniformity of spraying, and improve the prevention and control effect of leaf spot disease.

[0016] Preferably, the spore concentration of the Bacillus cereus aqueous solution is 1.3 billion spores / mL, etc. The spore concentration of the powder is 10 billion spores / g, etc.

[0017] Preferably, the Bacillus cereus aqueous solution is obtained by liquid fermentation, and the powder is obtained by solid fermentation.

[0018] The Bacillus cereus aqueous solution and powder described in the present application are obtained by the following method.

[0019] Preferably, the Bacillus cereus aqueous solution is prepared by the following method:

[0020] (a) Soil was collected from the "916" tea garden in Shucha Town, Shucheng County, and isolated and cultured on potato, glucose, corn flour, soybean flour, and agar culture media to obtain strains of Bacillus cereus;

[0021] (b) The Bacillus cereus strain is expanded and cultured to obtain a secondary strain of Bacillus cereus. In the Bacillus cereus aqueous solution, the liquid fermentation medium is 20% fresh potato liquid, 5% sucrose, 5% corn flour, 5% soybean powder, and 65% water, which are sterilized and cooled at high temperature. The cooled medium is added with 5% secondary strains, and fermented in a fermentation tank at a fermentation temperature of 36-37°C for 72 hours. The powder culture medium is 20% fresh potato, 15% corn kernels, 15% soybean powder, 5% sucrose, and 45% water. After high-temperature sterilization and cooling, the culture medium is placed in a sterilized container; a layer of secondary strains is spread on a layer of culture medium, and then placed in an incubator for fermentation at a fermentation temperature of 36-37°C, a humidity of 80%, and a time of 72 hours. It should be noted that after the separation and culture described in the present application, the spore content of the Bacillus cereus aqueous solution is at least 1.3 billion / mL, and the spores of Bacillus cereus cultured on a solid body are generally above 10 billion spores / gram.

[0022] Preferably, the separation and culture temperature is 36-37° C., and the separation and culture time is 72 h.

[0023] Preferably, the tea cake powder is obtained by crushing oil-tea tea cake.

[0024] Preferably, the particles of the tea cake powder are 1 to 10 μm.

[0025] Preferably, the oil-tea camellia kernels are hot-pressed or cold-pressed to obtain oil-tea camellia meal, and the oil-tea camellia meal is pressed and dehydrated to obtain the oil-tea camellia cake.

[0026] Tea cakes are obtained after hot or cold pressing. The tea cakes after pressing contain higher content of crude protein and crude fat, and are more easily used as nutrients for the germination or spore growth of Bacillus cereus.

[0027] Preferably, the oil-tea cake powder contains 11-13wt% of saponins, 11-17wt% of crude protein, 5-7wt% of crude fat, 3-5wt% of minerals and 24-35wt% of easily hydrolyzed polysaccharides.

[0028] The composition of the oil-tea tea cake powder can not only improve the dispersibility of Bacillus cereus, but also promote the spore production and hyphae growth of the Bacillus cereus, and the inhibitory effect of saponins on Bacillus cereus is not obvious.

[0029] As a preferred technical solution, step (1) "dispersing the Bacillus cereus amplification solution and tea cake powder in water to obtain a sprayable agent" can be carried out according to the following steps:

[0030] (1a) dispersing tea cake powder in a small amount of water to obtain a tea cake powder aqueous dispersion;

[0031] (1b) The tea cake powder aqueous dispersion is added to the remaining water, and then the Bacillus cereus propagation liquid is added to obtain a sprayable agent.

[0032] (1c) Adding the tea cake powder aqueous dispersion to the Bacillus cereus powder to obtain a sprayable agent.

[0033] Preferably, in step (1a), the tea cake powder aqueous dispersion is first subjected to ultrasonic pretreatment, and then steps (1b, 1c) are performed.

[0034] In the preferred embodiment, the tea cake powder aqueous dispersion is pretreated under ultrasonic conditions, which can unfold the secondary or tertiary structure of the protein, expose the lipophilic group and the hydrophilic group, and improve the water dispersibility of the protein in the tea cake powder. In particular, since the tea cake powder also contains some saponins, the dispersibility of the protein is further improved under the action of ultrasound, thereby improving the utilization rate of the protein by Bacillus cereus. In addition, since the protein in the treated tea cake powder aqueous dispersion also exposes the lipophilic group, it can improve its binding with fat, that is, it also increases the water solubility of fat to a certain extent, and can shorten the distance between fat and protein, and can also improve the utilization rate of fat and protein by Bacillus cereus. The use of ultrasound to pretreat the tea cake powder aqueous dispersion, combined with Bacillus cereus isolated and cultured from tea garden soil, can increase the 7d prevention effect of leaf spot disease to more than 74%, and the 15d prevention effect can reach more than 81%.

[0035] Preferably, the total amount of stearic acid added is 2.5-3.5 wt % of the mass of the tea cake powder.

[0036] The addition of stearic acid can defoam the ultrasonically pretreated tea cake powder aqueous dispersion without affecting the germination and growth of Bacillus cereus spores after spraying. In addition, due to the effective elimination of foam, the contact between Bacillus cereus and protein and fat is improved, thereby improving the germination and growth of Bacillus cereus spores.

[0037] Preferably, after step (1) is completed, step (2) is performed within 10 minutes.

[0038] After step (1) is completed, performing step (2) quickly can reduce the impact of saponins on Bacillus cereus spores, and after spraying, the water evaporates quickly, the Bacillus cereus spores come into contact with nutrients, and under the action of saponins, they quickly enter the peanut plant tissues to occupy space.

[0039] The second object of the present application is to provide a method for culturing Bacillus cereus, the method comprising the following steps:

[0040] (a) collecting soil from a tea garden, isolating and culturing it on potato, sucrose, corn flour, soybean flour, and agar culture media to obtain a strain of Bacillus cereus;

[0041] (b) The strain of Bacillus cereus is expanded and cultured to obtain a secondary strain of Bacillus cereus. The liquid fermentation medium is sterilized and cooled at high temperature according to the ratio of 20% fresh potato liquid, 5% sucrose, 5% corn flour, 5% soybean powder and 1L water. The cooled medium is added with 5% secondary strains and fermented in a fermentation tank at a fermentation temperature of 36-37°C for 72 hours. The powder culture medium is 20% fresh potatoes, 15% corn kernels, 15% soybean powder, 5% sucrose, and 45% water. After high-temperature sterilization and cooling, the culture medium is placed in a sterilized container. The method is: a layer of secondary strains is spread on a layer of culture medium, and then placed in an incubator for fermentation at a fermentation temperature of 36-37°C, a humidity of 80%, and a time of 72 hours. Preferably, the separation and fermentation culture temperature is 36-37°C, and the culture time is 72h.

[0042] The Bacillus cereus propagation material obtained by the Bacillus cereus cultivation method provided in the present application has a specific effect on peanut leaf spot disease.

[0043] Compared with the prior art, this application has the following beneficial effects:

[0044] (1) In the method for preventing peanut leaf spot provided by the present application, the spores produced by Bacillus cereus are used to germinate and invade the peanut plant tissue to occupy space, thereby inhibiting the spread of leaf spot disease in the peanut plant. The tea cake powder contains fat, protein, tea saponin and other ingredients, which can improve the dispersibility of the Bacillus cereus in water and provide nutrients for the germination of Bacillus cereus. Tea saponin itself has insecticidal and disease-preventing effects. The prevention and control of peanut leaf spot disease provided by the present application can reach more than 81% 15 days after the application.

[0045] (2) The Bacillus cereus propagation medium obtained by the cultivation method of Bacillus cereus provided in the present application has a specific effect on peanut leaf spot disease. DETAILED DESCRIPTION

[0046] The technical solution of the present invention is further explained below in conjunction with specific implementation methods. However, it should be noted that the specific implementation methods are only a specific implementation and explanation of the essence of the technical solution of the present invention, and should not be understood as a limitation on the protection scope of the present invention.

[0047] The reagents and instruments used in the examples can all be purchased from commercial products, and the detection methods are conventional methods well known in the art.

[0048] Culture Example 1

[0049] A method for culturing Bacillus cereus comprises the following steps:

[0050] (a) Sampling soil from tea gardens,

[0051] The strains of Bacillus cereus were isolated and cultured on potato, glucose, corn flour, soybean flour and agar medium; the light intensity of the incubator was ≤5×10 4 lx, culture temperature is 36-37°C, culture time is 72h;

[0052] (b) The strain BcSc of Bacillus cereus is expanded and cultured to obtain a secondary strain of Bacillus cereus; the liquid fermentation medium is sterilized at high temperature according to the ratio of 20% fresh potato liquid, 5% sucrose, 5% corn flour, 5% soybean flour and 1L water, and the isolated strain is added after cooling, and fermented and cultured on a shaker at a fermentation temperature of 36-37°C and a rotation speed of 156-159r / min, and the secondary strain. The spore concentration of the expanded Bacillus cereus is about 1.3 billion spores / ml.

[0053] Culture Example 2

[0054] A method for culturing a Bacillus cereus biological preparation comprises the following steps:

[0055] (a) Preparation method of Bacillus cereus aqueous solution: The propagation material is sterilized at high temperature according to the ratio of 20% fresh potato liquid, 5% sucrose, 5% corn flour, 5% soybean flour and 1L water, and then inoculated with 5% secondary bacteria after cooling, and cultured in a 50L fermenter. The culture temperature is 37±0.5℃, the culture time is 72h, and the spore concentration is about 1.3 billion spores / ml.

[0056] (b) Preparation method of Bacillus cereus powder: the propagation material is a propagation medium composed of 20% fresh potatoes, 15% corn kernels, 15% soybean powder, 5% sucrose, and 45% water. After high temperature sterilization and cooling, the culture medium is placed in a sterilized container. The method is: a layer of secondary bacteria is spread on a layer of culture medium, and then placed in an incubator for fermentation at a temperature of 36-37°C, a humidity of 80%, and a time of 72 hours. The propagation culture is carried out under a light intensity of less than 5×10 4 The spore concentration of the Bacillus cereus propagation medium is about 10 billion spores / gram.

[0057] Test 1: Indoor biological activity assay

[0058] Test method: including the following steps:

[0059] (a) Preparation method of Bacillus cereus BcSc spore suspension: The liquid fermentation medium is sterilized at high temperature according to the ratio of 20% fresh potato liquid, 5% sucrose, 5% corn flour, 5% soybean flour and 1L water, and then the isolated strain is inoculated after cooling, and fermented on a shaker at a temperature of 36-37°C and a rotation speed of 156-159r / min for 3 days. The spore concentration of the Bacillus cereus fermentation liquid is about 1.3 billion spores / mL. The above 1.3 billion spores / mL fermentation liquid is diluted to 10 8 spores / mL of fermentation broth (A);

[0060] (Note: (a) was used to prepare 10 8 Spores / mL of fermentation broth (NY3). Bacillus cereus NY3 is a known strain, see patent document CN106190932B, and its strain collection number is CGMCC NO.11962.

[0061] (b) Preparation method of tea cake powder suspension: accurately weigh 5 g of tea cake powder into 100 mL of distilled water, heat on an electric stove until slightly boiling, filter after cooling, collect the filtrate in a conical flask, sterilize at high temperature, and cool to obtain a filtrate (B);

[0062] (c) Antibacterial test method: The fermentation liquid (A) and the filtrate (B) were mixed in a volume ratio of 1:1, 1:2, 1:3, 2:1, and 3:1, respectively. 100 μl of the mixed liquids in different ratios were spread on a plate (PDA medium). After the spread liquid was slightly dry, the peanut leaf spot pathogen was inoculated in the center of the culture dish and cultured in a constant temperature incubator at 30°C for 3 days. The colony diameter was measured and the mycelium growth inhibition rate (%) was calculated.

[0063] Indoor antibacterial test results

[0064] The test was repeated three times with different ratios of Bacillus cereus to tea cake powder, and the colony diameter was measured 3 days after inoculation to calculate the inhibition rate. The results are shown in Table 1.

[0065]

[0066] Table 1 The results of different ratios of Bacillus cereus and tea cake powder on the mycelial growth inhibition of peanut leaf spot pathogen

[0067]

[0068] As can be seen from Table 1, there are certain differences in the inhibitory effects of different ratios on peanut leaf spot pathogens. 8The inhibition rates of spore liquid and tea cake powder at spores / mL on mycelium growth were 43.42% and 25.80%, respectively. The mycelium growth inhibition rates of each ratio were between 58.19% and 86.65%, which were higher than those of the spore liquid and tea cake powder alone. Among them, the inhibition rates of the 1:1 and 1:2 ratios were the highest, which were 72.95% and 86.65%, respectively.

[0069] In addition, Bacillus cereus BcSc is significantly more active than existing strains.

[0070] Test 2: Field efficacy determination

[0071] Embodiment 1:

[0072] (1) Test method: Peanut variety: Luhua No. 9, plot area: 20m 2 , 4 replicates. Apply the pesticide twice, with an interval of 10 days. The efficacy is investigated 15 days after the second application. In each plot, 5 points are investigated, and 4 peanut plants are investigated at each point. The total number of leaves, the number of diseased leaves and the disease level are counted.

[0073] Disease level standard:

[0074] Level 0: No disease

[0075] Level 1: The area of ​​lesions accounts for less than 5% of the entire leaf area;

[0076] Level 3 lesions account for 6 to 25% of the entire leaf area;

[0077] Level 5 lesions account for 26-50% of the entire leaf area;

[0078] Level 7 lesions account for 51-75% of the entire leaf area;

[0079] Level 9 lesions account for more than 75% of the entire leaf area

[0080] (2) dispersing 250 g of tea cake powder in 1 L of water to obtain a tea cake powder aqueous dispersion; the tea cake powder is obtained by crushing cold-pressed oil-tea tea cakes into 2-8 μm, and is determined to contain 12.5 wt % of saponins, 16.5 wt % of crude protein, 6.8 wt % of crude fat, 4.2 wt % of minerals and 28.2 wt % of easily hydrolyzed polysaccharides;

[0081] (3) adding 200 mL of Bacillus cereus aqueous solution to the obtained tea cake powder aqueous dispersion to obtain a sprayable agent;

[0082] (4) within 10 minutes, spraying the spray agent on the peanut plants;

[0083] (5) Apply the pesticide twice. The first application is when the peanut starts to bloom, and the second application is done 10 days later. See (1) for the survey method.

[0084] Example 2

[0085] (1) The implementation method is shown in Example 1 (1);

[0086] (2) taking 300 g of tea cake powder and dispersing it in 1 L of water to obtain a tea cake powder aqueous dispersion; the tea cake powder is obtained by crushing hot-pressed oil-tea tea cakes into 1-10 μm, and is determined to contain 11.8 wt % of saponins, 12.4 wt % of crude protein, 5.7 wt % of crude fat, 3.4 wt % of minerals and 24.1 wt % of easily hydrolyzed polysaccharides;

[0087] (3) adding 200 mL of Bacillus cereus aqueous solution to the obtained tea cake powder aqueous dispersion to obtain a sprayable agent; (4) spraying the sprayable agent on the peanut plants within 10 minutes;

[0088] (5) Apply the pesticide twice. The first application is at the beginning of flowering of peanuts, and the second application is done after an interval of 10 days. The investigation method is shown in Example 1 (1).

[0089] Example 3

[0090] (1) The implementation method is shown in Example 1 (1);

[0091] (2) 350 g of tea cake powder was dispersed in 1 L of water to obtain a tea cake powder aqueous dispersion; the tea cake powder was the same as that in Example 1 (2);

[0092] (3) adding 200 mL of Bacillus cereus aqueous solution to the obtained tea cake powder aqueous dispersion to obtain a sprayable agent;

[0093] (4) within 10 minutes, spraying the spray agent on the peanut plants;

[0094] (5) Apply the pesticide twice. The first application is at the beginning of flowering of peanuts, and the second application is done after an interval of 10 days. The investigation method is shown in Example 1 (1).

[0095] Example 4

[0096] (1) The implementation method is shown in Example 1 (1);

[0097] (2) 300 g of tea cake powder was dispersed in 1 L of water to obtain a tea cake powder aqueous dispersion; the tea cake powder was the same as that in Example 1 (2);

[0098] (3) adding 150 mL of Bacillus cereus aqueous solution to the obtained tea cake powder aqueous dispersion to obtain a sprayable agent;

[0099] (4) within 10 minutes, spraying the spray agent on the peanut plants;

[0100] (5) Apply the pesticide twice. The first application is at the beginning of flowering of peanuts, and the second application is done after an interval of 10 days. The investigation method is shown in Example 1 (1).

[0101] Example 5

[0102] (1) The implementation method is shown in Example 1 (1);

[0103] (2) 300 g of tea cake powder was dispersed in 1 L of water to obtain a tea cake powder aqueous dispersion; the tea cake powder was the same as that in Example 1 (2);

[0104] (3) adding 250 mL of Bacillus cereus aqueous solution to the obtained tea cake powder aqueous dispersion to obtain a sprayable agent;

[0105] (4) within 10 minutes, spraying the spray agent on the peanut plants;

[0106] (5) Apply the pesticide twice. The first application is at the beginning of flowering of peanuts, and the second application is done after an interval of 10 days. The investigation method is shown in Example 1 (1).

[0107] Example 6

[0108] (1) The implementation method is shown in Example 1 (1);

[0109] (2) 300 g of tea cake powder was dispersed in 1 L of water to obtain a tea cake powder aqueous dispersion; the tea cake powder was the same as that in Example 1 (2);

[0110] (3) adding 350 mL of Bacillus cereus aqueous solution to the obtained tea cake powder aqueous dispersion to obtain a sprayable agent;

[0111] (4) within 10 minutes, spraying the spray agent on the peanut plants;

[0112] (5) Apply the pesticide twice. The first application is at the beginning of flowering of peanuts, and the second application is done after an interval of 10 days. The investigation method is shown in Example 1 (1).

[0113] Example 7

[0114] (1) The implementation method is shown in Example 1 (1).

[0115] (2) 300 g of tea cake powder was dispersed in 1 L of water to obtain a tea cake powder aqueous dispersion; the tea cake powder was the same as that in Example 1 (2);

[0116] (3) adding 40 g of 10 billion spores / g of Bacillus cereus powder to the obtained tea cake powder aqueous dispersion to obtain a sprayable agent;

[0117] (4) within 10 minutes, spraying the spray agent on the peanut plants;

[0118] (5) Apply the pesticide twice. The first application is at the beginning of flowering of peanuts, and the second application is done after an interval of 10 days. The investigation method is shown in Example 1 (1).

[0119] Example 8

[0120] (1) The implementation method is shown in Example 1 (1).

[0121] (2) 300 g of tea cake powder was dispersed in 1 L of water to obtain a tea cake powder aqueous dispersion; the tea cake powder was the same as that in Example 1 (2);

[0122] (3) adding 50 g of 10 billion spores / g of Bacillus cereus powder to the obtained tea cake powder aqueous dispersion to obtain a sprayable agent;

[0123] (4) within 10 minutes, spraying the spray agent on the peanut plants;

[0124] (5) Apply the pesticide twice. The first application is at the beginning of flowering of peanuts, and the second application is done after an interval of 10 days. The investigation method is shown in Example 1 (1).

[0125] Example 9

[0126] (1) The implementation method is shown in Example 1 (1).

[0127] (2) 300 g of tea cake powder was dispersed in 1 L of water to obtain a tea cake powder aqueous dispersion; the tea cake powder was the same as that in Example 1 (2);

[0128] (3) adding 60 g of 10 billion spores / g of Bacillus cereus powder to the obtained tea cake powder aqueous dispersion to obtain a sprayable agent;

[0129] (4) within 10 minutes, spraying the spray agent on the peanut plants;

[0130] (5) Apply the pesticide twice. The first application is at the beginning of flowering of peanuts, and the second application is done after an interval of 10 days. The investigation method is shown in Example 1 (1).

[0131] Comparative Example 1

[0132] (1) The implementation method is shown in Example 1 (1);

[0133] (2) Take 1.3 billion spores / mL of the Bacillus cereus aqueous solution obtained in Culture Example 2 (a), use 250 mL of the preparation per mu, add 50 L of water, and obtain a sprayable agent;

[0134] (3) within 10 minutes, spraying the spray agent on the peanut plants;

[0135] (4) Apply the pesticide twice. The first application is at the beginning of flowering of peanuts, and the second application is done 10 days later. The survey method is shown in Example 1 (1).

[0136] Comparative Example 2

[0137] (1) The implementation method is shown in Example 1 (1);

[0138] (2) 300 g of tea cake powder was dispersed in 1 L of water to obtain a tea cake powder aqueous dispersion; the tea cake powder was the same as that in Example 1 (2).

[0139] (3) within 10 minutes, spraying the spray agent on the peanut plants;

[0140] (4) Apply the pesticide twice. The first application is at the beginning of flowering of peanuts, and the second application is done 10 days later. The survey method is shown in Example 1 (1).

[0141] Comparative Example 3

[0142] Use 1L of clean water as a blank control.

[0143] Field control results

[0144] The test was repeated 4 times for both the embodiment and the comparative example. The disease index was investigated 15 days after the second application of the pesticide. The test results are shown in Table 2.

[0145]

[0146]

[0147] Table 2 Field control results of the embodiments and comparative examples on peanut leaf spot

[0148]

[0149]

[0150] As can be seen from Table 2, the field control results of peanut leaf spot disease provided by the embodiments of the present application are good. The control effects of the Bacillus cereus aqueous solution, powder and tea cake powder composition on peanut leaf spot disease are all above 71%, especially Example 3 (350g tea cake powder + 200mL Bacillus cereus aqueous solution), the control effect is above 80%; Example 6 (300g tea cake + 350mL Bacillus cereus aqueous solution) has a higher control effect, which can reach above 84%.

[0151] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preventing and treating peanut leaf spot disease using a composition of Bacillus cereus and tea cake powder, characterized in that: The steps include: (1) dispersing the Bacillus cereus aqueous solution and tea cake powder in water to obtain a sprayable agent; the dispersion ratio of Bacillus cereus and tea cake powder in water is: 150-400 mL of Bacillus cereus + 200-400 g of tea cake powder; (2) compounding Bacillus cereus powder and tea cake powder to obtain a spraying agent; the ratio of the two is: 40-60 g of Bacillus cereus + 250-350 g of tea cake powder; (3) spraying the spraying agent of step (1) or step (2) on the peanut plants; The Bacillus cereus is Bacillus cereus ( Bacillus cereus )SC was deposited on July 27, 2023 at the General Microbiology Center of China Microorganism Culture Collection Administration, address: No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing, with the culture collection number CGMCC NO.28028; The spore concentration of the Bacillus cereus aqueous solution is 1.3 billion spores / mL, and the spore amount of the Bacillus cereus powder is 10 billion spores / g.

2. The method according to claim 1, characterized in that The bacillus cereus is obtained by liquid or solid fermentation.

3. The method according to claim 1 or 2, characterized in that: The oil-tea camellia kernels are hot-pressed or cold-pressed to obtain oil-tea camellia meal, and the oil-tea camellia meal is pressed and dehydrated to obtain tea cake powder.

4. The method according to claim 3, characterized in that The oil-tea cake powder contains 11-13 wt% of saponin substances, 11-17 wt% of crude protein, 5-7 wt% of crude fat, 3-5 wt% of minerals and 24-35 wt% of easily hydrolyzed polysaccharides.

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