Application of compound microbial agent in prevention and treatment of wheat scab

Abstract

The invention relates to application of a compound microbial agent in prevention and treatment of wheat scab. A bacterial strain in the compound microbial agent consists of a bacillus coagulans BC66 bacterial strain with the preservation number of CGMCC (China General Microbiological Culture Collection Center) 21879 and a lactobacillus plantarum LP194 bacterial strain with the preservation number of CGMCC 21766. The invention develops a brand new biocontrol preparation for preventing and treating wheat scab, active microorganisms of the biocontrol preparation consist of a bacillus coagulans BC66 strain and a lactobacillus plantarum LP194 strain, the research finds that the two strains are mutually matched and have synergistic interaction in the effect of preventing and treating wheat scab, and under the condition of consistent using bacterium amount, the biocontrol preparation has the effect of preventing and treating wheat scab. Compared with a single BC66 strain or a single LP194 strain, the effects are remarkably improved by compounding the two strains. Therefore, the compound microbial agent provides a new strategy for preventing and treating the wheat scab.

Description

[0001] This application claims the priority of a Chinese patent application with an application date of August 6, 2024, application number 202411069632.3, and invention name “Application of a composite microbial agent in the prevention and control of wheat fusarium rust”, all contents of which are incorporated by reference into this application. Technical Field

[0002] The invention belongs to the technical field of wheat planting and relates to application of a composite microbial agent in preventing and controlling wheat scab. Background Art

[0003] Wheat scab, also known as wheat ear blight, is one of the main diseases of wheat and one of the main factors for wheat yield reduction. In recent years, climate change and changes in farming systems (such as returning straw to the field and wheat-corn rotation) have promoted the accumulation of fungal sources in the field, aggravating the prevalence of wheat scab.

[0004] The disease mainly occurs in warm, humid and semi-humid areas. The infection of pathogens usually causes the "white ear" phenomenon in wheat ears. If infected in the early flowering stage, it will lead to the inability to produce grains, followed by shrinkage and withering. The infected wheat will not only cause a large-scale reduction in wheat grain production, but also produce a variety of fungal toxins, which seriously threaten the health of humans and animals. Therefore, actively responding to the prevention and control of wheat fusarium head blight is of great significance to human food safety production and human health.

[0005] At present, the prevention and control of wheat scab mainly depends on four aspects: breeding disease-resistant varieties, strengthening field management, chemical control and biological control, etc. Breeding disease-resistant varieties is one of the means to effectively control the harm of wheat scab, but breeding is difficult and the effect is poor, and progress is slow. Strengthening field management (including fertilization, crop rotation, weed removal, etc.) is also one of the methods for preventing and controlling wheat scab, but this method is not only time-consuming and laborious, but also has little effect. At present, chemical control methods are the main means of prevention and control of wheat scab, such as carbendazim, methyl thiophanate and other fungicides are the most widely used, but long-term and large-scale use of chemical agents will produce a series of problems, such as pathogens develop resistance, environmental pollution, soil degradation, etc. With people's pursuit of sustainable development of green agriculture, it is particularly important to develop green and efficient new pesticides.

[0006] Biological control agents have the advantages of not polluting the environment, being safe for humans and other organisms, leaving no residue, having strong specificity in killing pathogens, and being easy to coordinate with other plant protection measures. Therefore, developing more microbial agents for the prevention and control of wheat fusarium rust can not only enrich the resources of microbial strains that promote wheat fusarium rust, but also provide technical support for the in-depth research and development of functional strains, which is beneficial to green wheat production. Summary of the invention

[0007] In view of the deficiencies in the prior art, the object of the present invention is to provide an application of a composite microbial agent in preventing and controlling wheat fusarium head blight.

[0008] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides an application of a composite microbial agent in preventing and controlling wheat fusarium rust, wherein the strains in the composite microbial agent are composed of Bacillus coagulans BC66 strain with a preservation number of CGMCC 21879 and Lactobacillus plantarum LP194 strain with a preservation number of CGMCC 21766.

[0010] The present invention develops a new biocontrol agent for preventing and treating wheat scab, wherein the active microorganisms are composed of Bacillus coagulans BC66 strain and Lactobacillus plantarum LP194 strain. Studies have shown that the two strains cooperate with each other in the efficacy of preventing and treating wheat scab, and synergize to enhance the efficacy. When the amount of bacteria used is the same, the compound of the two bacteria significantly improves the above efficacy compared with a single BC66 strain or a single LP194 strain. Therefore, the composite microbial agent provides a new strategy for preventing and treating wheat scab.

[0011] Preferably, the ratio of the number of viable cells of the BC66 strain to that of the LP194 strain is (1-5):1, for example 1:1, 2:1, 3:1, 4:1, 5:1, etc. Other specific point values ​​within the above numerical range can be selected and will not be described one by one here.

[0012] Based on the potential interaction between the BC66 strain and the LP194 strain, the present invention also found that when the two strains are compounded in the above-mentioned specific ratio of viable bacteria count, their efficacy in preventing and controlling wheat fusarium rust is more significant.

[0013] Preferably, the content of live bacteria in the composite microbial agent is not less than 2×10 9 CFU / g or 2×10 9 CFU / mL, for example 2×10 9 CFU / mL (CFU / g), 5×10 9 CFU / mL (CFU / g), 1×10 10 CFU / mL (CFU / g), 1×10 11 CFU / mL (CFU / g), 1×10 12CFU / mL (CFU / g), etc.; other specific point values ​​within this numerical range can be selected and will not be described here one by one.

[0014] Preferably, the dosage form of the composite microbial agent includes solution, lyophilized powder, capsule, tablet or granule. The dosage form of the composite microbial agent involved in the present invention is not limited, including the most commonly used lyophilized powder, or further prepared capsule, tablet or granule.

[0015] Preferably, the composite microbial agent is in the form of a freeze-dried powder, which is prepared by a method comprising the following steps:

[0016] The BC66 strain and the LP194 strain are inoculated into a culture medium respectively for activation and fermentation culture in sequence to obtain a fermentation broth; the fermentation broth is centrifuged respectively, mixed with a protective agent and freeze-dried to obtain BC66 bacterial powder and LP194 bacterial powder; the BC66 bacterial powder and the LP194 bacterial powder are mixed according to the ratio of the number of live bacteria to obtain the composite microbial agent.

[0017] The protective agent includes any one of skim milk, gelatin, dextrin, gum arabic, dextran, sodium alginate, polyvinyl pyrrolidone, sucrose, lactose, trehalose, sorbitol or xylitol, or a combination of at least two thereof.

[0018] Preferably, the composite microbial agent is in the form of a solution, which is prepared by a method comprising the following steps:

[0019] The BC66 strain and the LP194 strain are inoculated into a culture medium respectively for activation and fermentation culture in sequence to obtain a fermentation broth; the fermentation broth is centrifuged respectively, and the bacterial sludge is resuspended to obtain a BC66 bacterial suspension and a LP194 bacterial suspension; the BC66 bacterial suspension and the LP194 bacterial suspension are mixed according to the ratio of the number of live bacteria to obtain the composite microbial agent.

[0020] In a second aspect, the present invention also provides a composite microbial agent for preventing and controlling wheat fusarium rust, wherein the strains in the composite microbial agent for preventing and controlling wheat fusarium rust are composed of Bacillus coagulans BC66 strain with a preservation number of CGMCC 21879 and Lactobacillus plantarum LP194 strain with a preservation number of CGMCC 21766.

[0021] The present invention develops a new microbial compounding method, in which Bacillus coagulans BC66 strain and Lactobacillus plantarum LP194 strain are compounded for preventing and treating wheat fusarium rust, and it is found that the two have potential interaction and can cooperate with each other to synergize in this effect.

[0022] Preferably, the ratio of the number of viable cells of the BC66 strain to that of the LP194 strain is (1-5):1, for example 1:1, 2:1, 3:1, 4:1, 5:1, etc. Other specific point values ​​within the above numerical range can be selected and will not be described one by one here.

[0023] Preferably, the content of live bacteria in the composite microbial agent is not less than 2×10 9 CFU / g or 2×10 9 CFU / mL, for example 2×10 9 CFU / mL (CFU / g), 5×10 9 CFU / mL (CFU / g), 1×10 10 CFU / mL (CFU / g), 1×10 11 CFU / mL (CFU / g), 1×10 12 CFU / mL (CFU / g), etc.; other specific point values ​​within this numerical range can be selected and will not be described here one by one.

[0024] In a third aspect, the present invention provides a method for preventing and controlling wheat fusarium rust, the method comprising: mixing the composite microbial agent described in the second aspect with wheat seeds, and then sowing and cultivating the treated wheat seeds.

[0025] In a fourth aspect, the present invention further provides use of the composite microbial agent described in the second aspect in the preparation of a drug for preventing and treating wheat fusarium head blight.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The present invention develops a new biocontrol agent for preventing and treating wheat scab, wherein the active microorganisms are composed of Bacillus coagulans BC66 strain and Lactobacillus plantarum LP194 strain. Studies have shown that the two strains cooperate with each other in the efficacy of preventing and treating wheat scab, and synergize to enhance the efficacy. When the amount of bacteria used is the same, the compound of the two bacteria significantly improves the above efficacy compared with a single BC66 strain or a single LP194 strain. Therefore, the composite microbial agent provides a new strategy for preventing and treating wheat scab.

[0028] The BC66 strain involved in the present invention is classified and named Bacillus coagulans. The preservation unit is the General Microbiology Center of China Microorganism Culture Collection Administration. The preservation time is March 8, 2021. The preservation number is CGMCC 21879. The address is: No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing.

[0029] The LP194 strain involved in the present invention is classified and named Lactobacillus plantarum, and the preservation unit is the General Microbiology Center of China Microorganism Culture Collection Administration. The preservation time is January 29, 2021, the preservation number is CGMCC 21766, and the address is: No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing. DETAILED DESCRIPTION

[0030] In order to further explain the technical means and effects adopted by the present invention, the technical solution of the present invention is further described below in conjunction with the preferred embodiments of the present invention, but the present invention is not limited to the scope of the embodiments.

[0031] The culture medium formula involved in the following examples is as follows:

[0032] PCA medium: 5.0 g of tryptone, 2.5 g of yeast extract powder, and 1.0 g of glucose were dissolved in 1 L of distilled water and the pH was adjusted to 7.0.

[0033] The BC66 strain involved in the following examples is classified and named Bacillus coagulans, deposited on March 8, 2021, and has a deposit number of CGMCC 21879.

[0034] The LP194 strain involved in the following examples is classified and named Lactobacillus plantarum, with a preservation date of January 29, 2021 and a preservation number of CGMCC 21766.

[0035] The preparation method of the bacterial powder involved in the following embodiment is as follows: inoculate the BC66 strain or the LP194 strain into a PCA liquid culture medium, culture at 37°C for 24 hours for activation, and activate twice continuously to obtain an activated solution; inoculate the activated solution into a PCA liquid culture medium at an inoculum amount of 5% (v / v), amplify and culture at 37°C to obtain a bacterial solution; centrifuge the bacterial solution at 5000 rpm for 10 minutes at 4°C, filter, obtain bacterial bodies, and then mix and emulsify with a protective agent (15% skim milk, 5% glycerol, 80% water) in a mass ratio of 1:1, and freeze-dry to obtain BC66 bacterial powder or LP194 bacterial powder, the number of viable bacteria is 1×10 10 CFU / g.

[0036] Example 1

[0037] Verification of the effect of composite microbial agents on the growth performance of wheat (variety Luomai 26):

[0038] (1) Grouping: The experiment was conducted in a wheat experimental field in Xinxiang City, Henan Province, and was divided into 7 groups: blank control group, positive control group, BC66 group (intervention with BC66 powder), LP194 group (intervention with LP194 powder), BC66+LP194 group 1 (intervention with BC66 powder and LP194 powder, with a live bacteria count ratio of 1:1), BC66+LP194 group 2 (intervention with BC66 powder and LP194 powder, with a live bacteria count ratio of 5:1), and ATCC7050+ATCC8014 group (intervention with commercially available Bacillus coagulans ATCC7050 powder and commercially available Lactobacillus plantarum ATCC8014 powder, with a live bacteria count ratio of 1:1).

[0039] (2) Planting method: The base fertilizer is commercially available Xinlianxin 15-15-15 compound fertilizer, 150 catties per mu. Soil type: sandy loam, soil fertility is good, the test temperature range is 10℃-35℃, soil moisture is controlled between 20%-60%, and the watering method is flooding, with a water volume of 50-85m 3 / mu, the experimental plot was divided into seven plots on average, with a 20cm aisle between plots, and each plot was 1.3×1.5m in shape. The planting density was 0.25m in row spacing per plot, and five rows were cultivated in each plot with a hoe, with a row spacing of 5cm, and 100 wheat seeds were planted in each plot. The cultivation and management measures of each group were the same.

[0040] (3) Intervention method: The control group used untreated wheat seeds for sowing. Each probiotic intervention group used different diluted aqueous solutions of bacterial agents to treat wheat seeds first. Specifically, 1 mL of the diluted aqueous solution of each group of bacterial agents (the concentration was 2×10 4 CFU / mL) was mixed with 15g wheat seeds, stirred evenly, and then the seeds were air-dried before sowing. The commercially available chemical product control group used Coolas seed coating agent (active ingredients are 22.6% thiamethoxam, 2.2% fludioxonil, and 2.2% difenoconazole) to treat wheat seeds first, specifically: 10g of Coolas seed coating agent was added to 1mL of water, mixed with 1kg wheat seeds, stirred evenly, and then the seeds were air-dried before sowing.

[0041] (4)Indicator analysis:

[0042] Observation of seedling data indicators was carried out 15 days after wheat sowing, including emergence rate (%), plant height (cm) and leaf length (cm). The results are shown in Table 1.

[0043] Table 1

[0044]

[0045] From the data results in Table 1, it can be seen that the germination rate of each intervention group was higher than that of the blank control group, and the various indicators of BC66+LP194 group 1 and BC66+LP194 group 2 were relatively better.

[0046] Example 2

[0047] Verification of the effect of compound microbial agents on the prevention and treatment of wheat (variety Luomai 26) fusarium head blight:

[0048] (1) The grouping method is the same as that in Example 1.

[0049] (2) Planting method: The base fertilizer is commercially available Xinlianxin 15-15-15 compound fertilizer, 150 catties per mu. Soil type: sandy loam, soil fertility is good, the test temperature range is 10℃-35℃, soil moisture is controlled between 20%-60%, and the watering method is flooding, with a water volume of 50-85m 3 / mu, the area of ​​the experimental field for planting wheat in each group was 7.2m×2m, and 300g of wheat seeds were planted in each group. Seven rows were cultivated in each experimental field with a hoe, and the spacing between each row was 100cm. The cultivation and management measures of each group were the same.

[0050] (3) The intervention method is the same as that in Example 1.

[0051] (4)Indicator analysis:

[0052] Observation of disease indicators including scab incidence (%) and control effect was carried out 7 months after wheat sowing, where control effect = (blank control group incidence - intervention group incidence) / blank control group incidence. The results are shown in Table 2.

[0053] Table 2

[0054]

[0055]

[0056] It can be seen from the data results in Table 2 that the incidence rate of each intervention group is lower than that of the blank control group, and the incidence rate of BC66+LP194 group 1 and BC66+LP194 group 2 is relatively lower, which shows that the microbial agent involved in the present invention has excellent effect in preventing and treating wheat fusarium rust, and the BC66 strain and the LP194 strain have synergistic effects in preventing and treating wheat fusarium rust.

[0057] The applicant declares that the present invention illustrates the technical solution of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned embodiments, that is, it does not mean that the present invention must rely on the above-mentioned embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

[0058] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0059] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

Claims

1. An application of a composite microbial agent in preventing and controlling wheat scab, characterized in that: The strains in the composite microbial agent are composed of Bacillus coagulans BC66 strain with a preservation number of CGMCC 21879 and Lactobacillus plantarum LP194 strain with a preservation number of CGMCC 21766.

2. The use according to claim 1, characterized in that: The ratio of the number of viable bacteria of the BC66 strain to that of the LP194 strain is (1-5):

1.

3. The use according to claim 1, characterized in that: The content of live bacteria in the composite microbial agent is not less than 2×10 9 CFU / g or 2×10 9 CFU / mL.

4. The use according to claim 1, characterized in that: The dosage form of the composite microbial agent includes solution, lyophilized powder, capsule, tablet or granule.

5. The use according to claim 4, characterized in that: The composite microbial agent is in the form of a freeze-dried powder, which is prepared by a method comprising the following steps: The BC66 strain and the LP194 strain are inoculated into a culture medium respectively for activation and fermentation culture in sequence to obtain a fermentation broth; the fermentation broth is centrifuged respectively, mixed with a protective agent and freeze-dried to obtain BC66 bacterial powder and LP194 bacterial powder; the BC66 bacterial powder and the LP194 bacterial powder are mixed according to the ratio of the number of live bacteria to obtain the composite microbial agent; The protective agent includes any one of skim milk, gelatin, dextrin, gum arabic, dextran, sodium alginate, polyvinyl pyrrolidone, sucrose, lactose, trehalose, sorbitol or xylitol, or a combination of at least two thereof.

6. The use according to claim 4, characterized in that: The composite microbial agent is in the form of a solution, which is prepared by a method comprising the following steps: The BC66 strain and the LP194 strain are inoculated into a culture medium respectively for activation and fermentation culture in sequence to obtain a fermentation broth; the fermentation broth is centrifuged respectively, and the bacterial sludge is resuspended to obtain a BC66 bacterial suspension and a LP194 bacterial suspension; the BC66 bacterial suspension and the LP194 bacterial suspension are mixed according to the ratio of the number of live bacteria to obtain the composite microbial agent.

7. A composite microbial agent for preventing and treating wheat scab, characterized in that: The strains in the composite microbial agent for preventing and controlling wheat fusarium rust are composed of Bacillus coagulans BC66 strain with a preservation number of CGMCC 21879 and Lactobacillus plantarum LP194 strain with a preservation number of CGMCC 21766.

8. The composite microbial agent according to claim 7, characterized in that: The ratio of the number of viable bacteria of the BC66 strain to that of the LP194 strain is (1-5):

1.

9. The composite microbial agent according to claim 7, characterized in that: The content of live bacteria in the composite microbial agent is not less than 2×10 9 CFU / g or 2×10 9 CFU / mL.

10. A method for preventing and controlling wheat scab, characterized in that: The method comprises: mixing the composite microbial agent according to any one of claims 7 to 9 with wheat seeds, and then sowing and cultivating the treated wheat seeds.

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