Seed coating agent for promoting stress resistance of plants as well as preparation method and application of seed coating agent

Abstract

The invention discloses a seed coating agent for promoting stress resistance of plants as well as a preparation method and application of the seed coating agent. The coating agent comprises an agent A, an agent B and an agent C, the agent A comprises ground phosphate rock, potassium mineral powder and biological carbon powder, the agent B comprises Marialea and / or Brevibacillus brevis, and the agent C comprises maltodextrin. The preservation number of the maziria is CCTCC (China Center For Type Culture Collection) NO: M2023996, and the preservation number of the brevibacillus is CCTCC NO: M2023995. The coating agent provided by the invention can improve the ability of plants to resist drought or salt adversity stress.

Description

Technical Field

[0001] The invention belongs to the technical field of microbial resource utilization and ecological agriculture, and relates to a seed coating agent for promoting plant stress resistance, and a preparation method and application thereof. Background Art

[0002] Elymus salsa is a high-quality forage grass that is easy to grow in the desert and has good feeding value. Livestock prefer to eat Elymus salsa during the tillering period. However, drought and poor soil reduce the plant coverage of the land, which further leads to low edible grass production, which is not only not conducive to the restoration of areas with severe desertification, but also limits related production. In recent decades, due to the increase in pastoral population and social and economic development, the pressure on grassland has increased, grassland overload and overgrazing have become increasingly serious, and grassland degradation has accelerated. Severe grassland degradation may lead to a sharp decline in the species diversity index, the risk of extinction of rare and endangered plants, the state of uncontrolled utilization of natural grasslands, the lack of opportunities for forage growth and renewal, the increasingly prominent contradiction between livestock and grass, and the serious imbalance of the grassland ecosystem balance system. Improving plant nutrient supply, especially increasing the levels of potassium and silicate, can help plants resist drought and salt stress. Microorganisms can promote the growth, yield and quality of plants under adverse stress through a series of functions and effects: produce a variety of plant hormones such as auxin to promote the development and construction of plant roots, increase nutrient and water absorption; stimulate plants to synthesize soluble sugars and proline and increase the activity of antioxidant enzymes such as SOD to reduce adverse stress such as drought; improve photosynthetic performance and enhance plant productivity; produce ACC deaminase to inhibit premature senescence or premature apoptosis of plants; inhibit the occurrence and development of diseases; etc. Nitrogen, phosphorus and potassium are large amounts of nutrients required for plant growth, and microorganisms can increase their supply through phosphorus and potassium solubilization and nitrogen fixation functions and effects. Drought and other adversities have the greatest impact on plant emergence and seedling growth. Coating plant seeds and reproductive roots or stems is an important means to promote plant emergence and seedling growth.

[0003] Currently, some patents related to seed coating can be retrieved. Among them, the most are coating agents related to chemical agents for controlling pests and diseases. There are also a small number of coating agents involving chemical substances and microorganisms. For example, the patent named "Coating composition for pathogen control in vegetables" (application number "201280030540.3") describes the combination of wax and some microorganisms to form a granular carrier to control pathogenic organisms; the patent named "Disease-resistant, insect-repellent, biological seed coating bacterial agent and preparation method thereof" (application number "201710206032.0") describes the mixture of Pseudomonas fluorescens, Bacillus subtilis and chitin to form a liquid coating agent to control pests and diseases; the patent named "A microbial seed coating The patent entitled "Preparation method and application thereof" (application number "201910299546.4") emphasizes the use of thick-walled spores of Trichoderma, and coating technology bonded with diatomaceous earth, cyclodextrin, etc., mainly to solve the problem of short shelf life of Trichoderma spores; the patent entitled "A microbial seed pelletized coating composition" (application number "201910124557.9") describes the use of calcium peroxide to compound a variety of Bacillus and molds to form a microbial coating composition, so as to prevent and control diseases and improve seed germination in barren land; and so on. Summary of the invention

[0004] Based on the technical problems existing in the prior art, the first purpose of the present invention is to provide a microorganism that promotes plant stress resistance; the second purpose of the present invention is to provide a coating agent that promotes plant stress resistance; the third purpose of the present invention is to provide a method for preparing a coating agent that promotes plant stress resistance; the fourth purpose of the present invention is to provide the application of a composite coating agent in promoting plant stress resistance.

[0005] In one aspect, the present invention provides an isolated microorganism, comprising Massilia sp. and / or Brevibacillus parabrevis, wherein the deposit number of Massilia sp. is CCTCC NO: M2023996, and the deposit number of Brevibacillus parabrevis is CCTCC NO: M2023995. In some preferred embodiments, the microorganism is a group consisting of Massilia sp. and Brevibacillus parabrevis.

[0006] The Massilia sp. strain (Massilia sp.EPRRC13) and the Brevibacillus parabrevis strain (Brevibacillus parabrevis EPRRN17) in the present invention have been deposited in the China Center for Type Culture Collection on June 12, 2023. The deposit number of Massilia sp.EPRRC13 is CCTCC NO: M2023996, and the deposit number of Brevibacillus parabrevis EPRRN17 is CCTCC NO: M2023995.

[0007] In the present invention, the functions of the microorganisms include but are not limited to producing plant hormones such as auxin, gibberellins, cytokinins, or jasmonic acid, dissolving calcium phosphate-phosphorus (phosphate rock powder-phosphorus), dissolving potassium (potassium rock powder-potassium), autogenous nitrogen fixation, producing ACC (2,4-diacetyl garcinol) deaminase, producing siderophores, producing HCN (hydrocyanic acid) or producing DAPG (2,4-diacetyl garcinol). One or more of the microorganisms can produce extracellular polysaccharides and form biofilms. The microorganisms have no obvious antagonism with each other.

[0008] On the other hand, the present invention provides a composition, which includes agent A, agent B and agent C, wherein the agent A includes phosphate rock powder, potassium rock powder, and biocarbon powder, the agent B includes the microorganisms described above, and the agent C includes maltodextrin.

[0009] In the present invention, the biochar powder is obtained by crushing and high-temperature decomposing discarded plants of various plants, and together with the polysaccharides produced by the microorganisms and other materials, forms a well-ventilated membrane, which can better utilize its own pore size to adsorb microorganisms, thereby achieving the effect of storing microorganisms, and can be sterilized at high temperature before use.

[0010] In some preferred embodiments, the microorganism is a combination of the Massilia bacteria and the Brevibacillus. In some particularly preferred embodiments, the effective viable count ratio of the Massilia bacteria and the Brevibacillus is (1-3):(1-3). More preferably, the effective viable count ratio of the Massilia bacteria and the Brevibacillus is 1:1.

[0011] In some preferred embodiments, the effective viable count of the microorganism in the composition is 10 9 -10 12 CFU / g.

[0012] In some preferred embodiments, the weight ratio of the A agent, the B agent and the C agent is (1000-1500): (1-5): (1000-2500). More preferably, the weight ratio of the A agent, the B agent and the C agent is 1050:4:1300.

[0013] In some preferred embodiments, the weight ratio of the phosphate rock powder, potash rock powder and bio-carbon powder is (5-10): (5-10): (200-400). In some more preferred embodiments, the weight ratio of the phosphate rock powder, potash rock powder and bio-carbon powder is 1:1:40.

[0014] In some embodiments, the agent A further comprises EDTA and / or fulvic acid.

[0015] In some embodiments, the agent C further comprises trehalose and / or molasses.

[0016] In an embodiment of the present invention, the concentration of maltodextrin is 30% of the total amount of Agent C.

[0017] As a preferred embodiment, the agent C comprises maltodextrin and molasses. More preferably, the ratio of maltodextrin to molasses is 5:1. More preferably, in the agent C, the total mass percentage concentration of the maltodextrin and molasses is 30-60%.

[0018] In a specific embodiment of the present invention, the C agent includes 1000 mL of sterile water, 50 g of molasses, and 250 g of maltodextrin.

[0019] In some embodiments, the composition can be prepared as one or more of the following formulations: emulsions, colloids, powders, granules, pellets, dusts, sprays, emulsions, and solutions.

[0020] In some preferred embodiments, the composition is a coating agent.

[0021] Another aspect of the present invention provides a method for promoting plant stress resistance or preventing and controlling plant diseases, wherein the method comprises applying the aforementioned microorganism or the aforementioned composition to the plant or its seeds, or to the surrounding environment of the plant or its seeds,

[0022] In some preferred embodiments, the method comprises stirring the composition and the seeds of the plant evenly. More preferably, each stirring needs to be air-dried for at least 10-12 hours to ensure sufficient adsorption, and the seeds are sown in time after air-dried, or sealed in a clean packaging bag and stored in a cool place for no more than 2 days before sowing.

[0023] In some preferred embodiments, the weight and volume ratio of the plant seeds to the composition is (50-100 kg): (1-5 L). More preferably, the weight and volume ratio of the plant seeds to the composition is 50 kg: 1 L.

[0024] In some preferred embodiments, the promoting plant stress resistance includes improving the ability of the plant to resist drought or salt stress.

[0025] In some preferred embodiments, the plant is Elymus dahliae.

[0026] Another aspect of the present invention provides a method for preparing a composite coating agent, which comprises the following steps:

[0027] The aforementioned microorganisms are activated, cultured, and collected by centrifugation to obtain the aforementioned agent B;

[0028] The aforementioned agent C is formulated into a solvent;

[0029] Add agent B to agent C and stir evenly; add agent A mentioned above to the mixed solution of agent B and agent C to obtain a composite coating agent.

[0030] In some preferred embodiments, the microorganism is a combination of Massilia sp. and Brevibacillus parabrevis. The two microorganisms can be cultured separately or mixed.

[0031] In some preferred embodiments, the weight-to-volume ratio of the agent A to the mixed solution is (1-1.5 kg): (1-2.5 L).

[0032] In some preferred embodiments, the effective viable count of the microorganisms in the composite coating is 10 9 -10 13 In some preferred embodiments, the culture comprises shake flask culture and fermenter amplification culture.

[0033] In some embodiments, the composite coating agent of the present invention can be prepared and used immediately.

[0034] Another aspect of the present invention provides the following application:

[0035] (1) Use of the aforementioned microorganisms or the aforementioned compositions in the preparation of products for promoting plant stress resistance or preventing and controlling plant diseases;

[0036] (2) Use of the aforementioned microorganisms or the aforementioned compositions in promoting plant stress resistance or preventing and controlling plant diseases.

[0037] In some preferred embodiments, the product comprises a coating agent or a fertilizer.

[0038] In some preferred embodiments, the promoting plant stress resistance includes improving the ability of the plant to resist drought or salt stress.

[0039] In some preferred embodiments, the plant is Elymus dahliae.

[0040] Definition of terms

[0041] Elymus dahuricus Turcz. is a sparse, upright plant of the genus Elymus in the Poaceae family. The plant height of Elymus dahuricus is 70-140 cm, with sparse culms, smooth and hairless leaf sheaths, and dense spike inflorescences. The plant mainly grows on hillside grasslands or roadsides. It is drought-resistant, cold-resistant, alkali-resistant, and wind-resistant. The flowering and fruiting period is from July to September, and it is mainly used as forage.

[0042] "Promoting plant stress resistance" includes but is not limited to promoting the growth, yield and quality of plants under adverse stress, producing a variety of plant hormones such as auxin to promote the development and construction of plant roots, increasing nutrient and water absorption, stimulating plants to synthesize soluble sugars and proline, and increasing the activity of antioxidant enzymes such as SOD to reduce adverse stress such as drought, improve photosynthetic performance, enhance plant productivity, produce ACC deaminase, inhibit premature senescence or premature apoptosis of plants, and inhibit the occurrence and development of diseases.

[0043] Beneficial effects:

[0044] The present invention screened and obtained strains with strong plant growth-promoting functions for the first time, including Massiliasp. and Brevibacillus parabrevis. The present invention specifically clarifies the functions that functional microorganisms should have, which facilitates the combination of strains according to local conditions in production, is more open and will have wider applications.

[0045] The present invention discloses a coating agent, which can not only prevent and treat diseases, but also achieve the purpose of improving plant resistance to drought and salt stress. The coating agent of the present invention is different from the material combination of the composite coating agent in the prior art, especially using low-cost mineral powder, such as silicate mineral powder, etc., and there is no composite coating agent containing all the same materials. In the coating agent of this patent, different functional components are packaged separately and mixed in proportion when used, which is more conducive to ensuring the survival of microorganisms, extending the storage time, and ensuring the coating effect. The material components and proportions of the coating agent of the present invention are suitable for the cultivation of Elymus salsa. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 The effects of different treatments on the plant height of Elymus dahliae;

[0047] Figure 2 Effects of different treatments on the aboveground fresh weight of Elymus salsa.

[0048] Deposit of microorganisms for patent procedures:

[0049] 1. Massilia sp. EPRRC13 of the present invention

[0050] Deposit date: June 12, 2023;

[0051] Depository: China Center for Type Culture Collection (CCTCC);

[0052] Deposit number: CCTCC NO:M2023996;

[0053] Classification and nomenclature: Massilia sp.;

[0054] Storage address: No. 299, Bayi Road, Wuchang District, Wuhan City, Hubei Province.

[0055] 2. Brevibacillus parabrevis EPRRN17 of the present invention

[0056] Deposit date: June 12, 2023;

[0057] Depository: China Center for Type Culture Collection (CCTCC);

[0058] Deposit number: CCTCC NO:M2023995;

[0059] Classification name: Brevibacillus parabrevis

[0060] Storage address: No. 299, Bayi Road, Wuchang District, Wuhan City, Hubei Province. DETAILED DESCRIPTION

[0061] Before further describing the specific embodiments of the present invention, it should be understood that the scope of protection of the present invention is not limited to the specific embodiments described below; it should also be understood that the terms used in the examples of the present invention are for describing the specific embodiments rather than for limiting the scope of protection of the present invention.

[0062] When the embodiments give numerical ranges, it should be understood that, unless otherwise specified in the present invention, both endpoints of each numerical range and any numerical value between the two endpoints can be selected. Unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as those generally understood by those skilled in the art. In addition to the specific methods, equipment, and materials used in the embodiments, according to the grasp of the prior art by those skilled in the art and the record of the present invention, any methods, equipment, and materials of the prior art similar or equivalent to the methods, equipment, and materials described in the embodiments of the present invention can also be used to realize the present invention.

[0063] Unless otherwise stated, the experimental methods, detection methods, and preparation methods disclosed in the present invention all adopt conventional techniques in the technical field.

[0064] Example 1 Isolation and Identification of Bacteria

[0065] The wild Elymus dahliae plants were collected, and the strain functions of plant growth-promoting traits such as nitrogen fixation, phosphorus solubilization, potassium solubilization, plant hormone production, iron carrier production and ACC deaminase production in the rhizosphere were isolated by coating and streaking technology; the genomic DNA of the isolated and purified strains was used as a template, 27F and 1492R were used as primers, and the 16S rRNA gene of the strains was amplified by PCR, and the amplified products were sequenced. The obtained sequences were classified by online EzTaxon (the 16S rRNA gene sequence similarity greater than 97% was preliminarily determined to be the same species), and the 16S rRNA gene sequences of the 9 bacterial strains obtained were 98% to 100% similar to the model species. The results are shown in Table 1, which shows the 16S rRNA gene similarity analysis of strains with strong plant growth-promoting functions.

[0066] Table 1 Strain isolation information

[0067]

[0068] Example 2 Bacteria activation, cultivation and collection

[0069] Activate and culture strains with strong plant growth-promoting ability: 100 mL of glycerol-containing bacterial solution was applied to solid culture medium with corresponding ability, such as nitrogen fixation or phosphorus and potassium solubilization, and cultured at 25°C. Single colonies with typical colony characteristics and rapid growth were selected and placed in modified corresponding liquid culture medium, and cultured at 25°C. When cultured to the middle and late logarithmic phase, the cells were centrifuged at 8000 g, washed repeatedly with K2HPO4-KH2PO4 buffer (pH 7.2) for 3 times, and then resuspended with the same buffer to a cell concentration of 10 13 CFU / mL.

[0070] Example 3 Determination of basic biological characteristics of strains and their plant growth-promoting ability

[0071] The Massilia sp. strain (Massilia sp.EPRRC13) and the Brevibacillus parabrevis strain (Brevibacillus parabrevis EPRRN17) in the present invention have been deposited in the China Center for Type Culture Collection on June 12, 2023. The deposit number of Massilia sp.EPRRC13 is CCTCC NO: M2023996, and the deposit number of Brevibacillus parabrevis EPRRN17 is CCTCC NO: M2023995.

[0072] The effects of salinity, temperature and pH on bacterial growth were determined, and qualitative or quantitative determination of plant growth-promoting abilities was performed using nitrogen fixation, phosphorus solubilization, potassium solubilization and other culture media. Some of the results are shown in Table 2. It can be seen that Massilia sp. (MC) and Brevibacillus parabrevis (BP) have multiple growth-promoting abilities and are more adaptable to the climate or geological conditions (large temperature difference, drought and salinity, etc.) in the arid areas of the north. Subsequent plate confrontation analysis found that there was no mutual antagonism between the strains, and mixed inoculation had a better effect on promoting the growth of Elymus salsa than single coating inoculation.

[0073] Table 2 Single strain inoculation experiment

[0074]

[0075] Example 4 Coating Preparation and Application Method

[0076] Step 1: Microbial culture: Activate, culture in shake flasks and amplify in fermenter with corresponding functional microbial strains using phosphate-dissolving, potassium-dissolving and nitrogen-fixing medium respectively; collect cells by centrifugation; mix cells of various strains, freeze-dry or add protective agents such as glycerol to store at low temperature for standby use, or use directly. Thus, Agent B is prepared.

[0077] Step 2: Preparation of Agent A and Agent C: First, sterilize the biocarbon powder at high temperature, then weigh each substance by weight or volume, mix evenly according to the components of Agent A and Agent C, seal and store at room temperature for later use, or use directly. Agent A and Agent C are prepared in this way.

[0078] Step 3: Preparation of composite coating agent: Add B to C, then add an appropriate amount of sterile water that has been filtered or sterilized at high temperature, and stir evenly in a clean environment; add agent A to the mixture of B and C, with a weight volume ratio of

[0079] (1-1.5kg): (1-2.5L), and the effective viable count is 10 9 -10 12 CFU / mL, ready for use.

[0080] Step 4. Application of the composite coating agent: The weight and volume ratio of the composite coating agent mixture prepared in step 3 is 50kg:1L. The composite coating agent mixture and the Elymus salsa seeds are evenly stirred. After each stirring, they need to be air-dried for at least 10-12 hours to ensure sufficient adsorption. After drying, sow the seeds in time, or seal them in clean packaging bags and store them in a cool place for no more than 2 days before sowing.

[0081] The above-mentioned agent B is a single microbial strain or a combination of microbial strains involved in the present invention, and the dosage is 4g;

[0082] The above-mentioned agent A is 25g of phosphate rock powder, 25g of potash rock powder, and 1000g of biocarbon powder;

[0083] The above-mentioned Agent C is 1000 mL of sterile water, 50 g of molasses, and 250 g of maltodextrin;

[0084] In this embodiment, the weight ratio of agent A, agent B and agent C is 1050:4:1300.

[0085] Example 5 Optimization of non-biological coating components

[0086] Using PEG6000 to simulate drought stress in potted Elymus dahliae, based on single factor research, the total number of viable bacteria of composite bacteria MC and BP, the emergence speed and size of Elymus dahliae at 15 days, and adhesion (the shedding rate after being shaken upside down at a speed of 100 rpm for 10 minutes after drying, i.e., the weight of seed coating material falling / the total weight of coating material before falling) were comprehensively selected to optimize the non-biological coating component ratio. Some results are shown in Tables 3 to 5. Tables 3 to 5 show that combination 1 has excellent comprehensive effects in coating effect and growth promotion, and is the preferred component ratio combination.

[0087] Table 3 Optimization of Massilia sp.EPRRC13 single bacterial coating

[0088]

[0089] The combination number represents: 1, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 10:10:400; 2, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 10:10:350; 3, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 10:10:200; 4, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 5:5:300; 5, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 10:10:200; The weight ratio of the powder is 10:5:300; 6, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 5:10:300; 7, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 7:7:400; 8, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 7:7:300; 9, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 7:7:200; 10, CK (uncoated).

[0090] Table 4 Optimization of single bacterial coating of Brevibacillus parabrevis EPRRN17

[0091]

[0092]

[0093] The combination number represents: 1, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 10:10:400; 2, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 10:10:350; 3, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 10:10:200; 4, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 5:5:300; 5, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 10:10:200; The weight ratio of the powder is 10:5:300; 6, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 5:10:300; 7, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 7:7:400; 8, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 7:7:300; 9, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 7:7:200; 10, CK (uncoated).

[0094] Table 5 Composite strain coating optimization experiment

[0095]

[0096] The combination number represents: 1, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 10:10:400; 2, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 1010350; 3, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 10:10:200; 4, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 5:5:300; 5, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 10:5:300; 6, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 5:10:300; 7, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 7:7:400; 8, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 7:7:300; 9, the weight ratio of phosphate rock powder, potassium ore powder and bio-carbon powder is 7:7:200; 10, CK (uncoated).

[0097] Example 6

[0098] Strain culture medium formula:

[0099] R2A complete nutrient medium: soluble starch 2.5 g, glucose 2.5 g, bacteriological peptone 2.5 g, acid hydrolyzed casein 2.5 g, yeast extract 2.5 g, K2HPO3·3H2O 1.5 g, sodium pyruvate 1.5 g, MgSO4·7H2O 0.25 g, distilled water 1000 mL.

[0100] The specific implementation steps are as follows: activate strains Massilia sp. and Brevibacillus parabrevis in R2A liquid culture medium, culture in liquid for 2-3 days, collect the cells by centrifugation, mix the two cells in a slurry at a ratio of 1:1, and the total number of live bacteria in the slurry is about 10 11 CFU / g. After obtaining the bacterial sludge, it was diluted with sterile water to make a bacterial suspension with a bacterial suspension concentration of about 10 9 CFU / mL. Agent A is mixed with agent B according to a certain proportion, and then mixed with agent C to obtain a composite coating agent.

[0101] The above-mentioned agent B is bacterial mud.

[0102] The above-mentioned Agent A is 25g of phosphate rock powder, 25g of potassium rock powder, and 1000g of bio-carbon powder.

[0103] The above-mentioned Agent C is composed of 1000 mL of sterile water, 50 g of molasses, and 250 g of maltodextrin.

[0104] The weight ratio of agent A, agent B and agent C is 1050:4:1300.

[0105] Single strain coating, sterile coating and blank treatment were also prepared. The preparation method of single strain coating is the same as that of composite strain coating, except that the B agent contains only a single strain. In the B agent bacterial sludge, the number of viable bacteria of a single strain is about 10 11CFU / g.

[0106] The experimental results are shown in Table 6. Figure 1 , Figure 2 As shown, the mixed inoculation of Massilia sp. strain (MC) and Brevibacillus parabrevis strain (BP) had a better effect on promoting the growth of Elymus dahliae than single coating inoculation.

[0107] Table 6

[0108]

[0109] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. An isolated microorganism comprising Massilia sp. and / or Brevibacillus parabrevis, wherein the Massilia sp. has a deposit number of CCTCC NO: M2023996 and the Brevibacillus parabrevis has a deposit number of CCTCC NO: M2023995.

2. A composition comprising agent A, agent B and agent C, wherein: The agent A comprises phosphate rock powder, potash rock powder, and biocarbon powder. The agent B comprises the microorganism according to claim 1, The agent C includes maltodextrin.

3. The composition according to claim 2, wherein The microorganism is a combination of the Marsiliensis and the Brevibacillus. More preferably, the ratio of the effective viable counts of the Marsiliensis and the Brevibacillus is (1-3):(1-3). Preferably, the ratio of the effective viable counts of the Marsiliensis and the Brevibacillus is 1:

1.

4. The composition according to claim 2, wherein the weight ratio of agent A, agent B and agent C is (1000-1500):(1-5):(1000-2500), preferably 1050:4:1300.

5. The composition according to claim 2, wherein The weight ratio of the phosphate rock powder, potash rock powder and biocarbon powder is (5-10): (5-10): (200-400). Preferably, the weight ratio of the phosphate rock powder, the potassium rock powder and the bio-carbon powder is 1:1:

40.

6. The composition according to claim 2, wherein The agent A also includes EDTA and / or fulvic acid, Preferably, the agent C further comprises trehalose and / or molasses.

7. The composition according to any one of claims 2 to 6, wherein The composition is a coating agent.

8. A method for promoting plant resistance or preventing and controlling plant diseases, wherein: The method comprises applying the microorganism according to claim 1 or the composition according to any one of claims 2 to 7 to the plant or its seed, or to the surrounding environment of the plant or its seed, Preferably, the method comprises stirring the composition and the seeds of the plant evenly, and preferably, the weight and volume ratio of the seeds of the plant to the composition is (50-100 kg): (1-5 L); Preferably, the promoting plant stress resistance comprises improving the ability of plants to resist drought or salt stress. Preferably, the plant is Elymus dahliae.

9. A method for preparing a composite coating agent, comprising the following steps: Activating and culturing the microorganism described in claim 1, and collecting by centrifugation to obtain the agent B described in any one of claims 2 to 7; The agent C described in any one of claims 2 to 7 is formulated into a solvent; Add agent B to agent C and stir evenly; add agent A described in any one of claims 2 to 7 to the mixed solution of agent B and agent C to obtain a composite coating agent; Preferably, the weight-to-volume ratio of the agent A to the mixed solution is (1-1.5 kg): (1-2.5 L); Preferably, the effective viable count of microorganisms in the composite coating is 10 9 -10 13 CFU / mL.

10. Application as follows: (1) Use of the microorganism according to claim 1 or the composition according to any one of claims 2 to 7 in the preparation of a product for promoting plant stress resistance or preventing and controlling plant diseases; (2) Use of the microorganism according to claim 1 or the composition according to any one of claims 2 to 7 in promoting plant stress resistance or preventing and controlling plant diseases; Preferably, the promoting plant stress resistance comprises improving the ability of plants to resist drought or salt stress; Preferably, the plant is Elymus dahliae.

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