Clonostachys rosea and application thereof

Abstract

The invention relates to the field of biological prevention and control, in particular to a clonostachys rosea and application of the clonostachys rosea. The spiropolyspora rosea is preserved in the China General Microbiological Culture Collection Center (CGMCC) on April 18, 2022, the address is Institute of Microbiology, Chinese Academy of Sciences, No.3, No.1 Yard, Beichen West Road, Chaoyang District, Beijing, and the preservation number is CGMCC No.40130. The spiropolyspora rosea can be used for preparing the feed additive. The microbial agent containing the clonostachys rosea, which is prepared by the preparation method disclosed by the invention, not only can be used for preventing and treating the southern blight of the peanuts, but also can be used for increasing the yield of the peanuts.

Description

Technical Field

[0001] The invention relates to the field of biological control, and in particular to Clonostachys rosea and applications thereof. Background Art

[0002] White rot of peanut caused by Sclerotium solani is a soil-borne fungal disease of peanut. Peanut can be infected by white rot fungi at all growth stages, mainly harming the stems, fruit stalks, pods and roots of the plants. White rot occurs in most peanut production areas in China. Recently, due to changes in farming systems, large-scale promotion of high-yield new varieties and changes in climatic conditions, the occurrence and damage have become more serious year by year. It has developed into one of the important diseases of peanuts and has become an important factor restricting peanut yield and quality.

[0003] Due to the lack of natural resistance resources and the limited number of disease-resistant resources that have been identified and developed, traditional breeding methods have failed to effectively control the harm of these pathogens and their toxins. For a long time, the prevention and control of white rot has mainly relied on chemical fungicides, which has led to serious environmental pollution and ecological environmental problems, and induced the resistance of pathogens and the increase of toxin production.

[0004] Therefore, there is an urgent need to develop a biological control strain that is safe for the ecology and environment and apply it to the prevention and control of peanut white rot. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a low-cost biocontrol bacterium: Clonostachys rosea. The microbial agent containing Clonostachys rosea prepared by the present invention can not only prevent and control peanut white rot, but also increase the yield of peanuts.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] In the first aspect, the present invention provides a pink spiral polysporus (Clonostachys rosea), which has been deposited in the General Microbiology Center of China National Microbiological Culture Collection Committee on April 18, 2022, with the address: Institute of Microbiology, Chinese Academy of Sciences, No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, and the deposit number is CGMCC No.40130.

[0008] The pink spiral Clonostachys rosea isolated by the present invention can prevent and control peanut white rot, and the microbial agent prepared by the pink spiral Clonostachys rosea has a control effect of more than 84.5% on peanut white rot. The microbial agent can also increase the yield of peanuts. After treatment, the yield increase rate of peanuts can reach 64.7%.

[0009] Preferably, the rDNA-ITS sequence of Polyspora rosea is as shown in SEQ ID NO.1.

[0010] In a second aspect, the present invention provides the use of the above-mentioned pink spiral polyporus in preventing and controlling peanut white rot.

[0011] In a third aspect, the present invention provides the use of the above-mentioned pink spiral polysporus in the preparation of a fungal agent for preventing and controlling peanut white rot.

[0012] Preferably, the peanut white rot is caused by infection by Sclerotium solani.

[0013] In a fourth aspect, the present invention provides a microbial agent for preventing and controlling white rot of peanut, wherein the raw material for preparing the microbial agent comprises the fermentation broth of the above-mentioned Clonostachys rosea; and the preparation method of the fermentation broth comprises the following steps:

[0014] (1) inoculating the pink spiral polysporus on a solid culture medium for activation; inoculating the pink spiral polysporus on a liquid culture medium for culturing to obtain a seed solution;

[0015] (2) inoculating the seed liquid obtained in step (1) into a fermentation medium for cultivation, and filtering to obtain the fermentation liquid.

[0016] Preferably, the solid culture medium and the liquid culture medium are both PDA culture medium.

[0017] Preferably, the activation condition is culturing at 25°C for 5 hours.

[0018] Preferably, in step (1), the culture conditions are: culture at 28° C. and 180 rpm on a shaker for 3 days.

[0019] Preferably, in step (2), the inoculation amount of the seed solution is 2%.

[0020] Preferably, the fermentation medium comprises the following components in weight percentage: 1%-3% corn flour, 1-2% fish meal, 0.1%-0.5% maltose, 0.1%-0.2% manganese sulfate, 0.1%-0.2% potassium dihydrogen phosphate, and the balance water.

[0021] Preferably, the pH of the fermentation medium is 7.0-8.0.

[0022] Preferably, the raw materials for preparing the microbial agent also include at least one of sodium alginate, bentonite, skim milk, chitosan oligosaccharide, and CaCl2.

[0023] The above-mentioned raw materials can effectively adsorb or protect bacteria.

[0024] Preferably, the microbial agent comprises the following raw materials in percentage by mass: 25%-30% fermentation broth of pink spiral polysporus, 1%-2% sodium alginate, 1%-4% bentonite, 1%-4% skim milk, 1%-2% chitosan oligosaccharide, 1%-3% CaCl2, and water is added to 100%.

[0025] More preferably, the microbial agent comprises the following raw materials in percentage by mass: 30% fermentation broth of pink spiral polysporus, 2% sodium alginate, 3% bentonite, 2% skim milk, 1% chitosan oligosaccharide, 3% CaCl2, and water is added to 100%.

[0026] Preferably, the number of viable bacteria in the pink spiral polysporus fungus agent is 7.0×10 8 CFU / g-7.8×10 8 CFU / g.

[0027] In the fermentation bacterial liquid, the number of live bacteria of Pink Spirochromocybe is not less than 50 billion / gram.

[0028] Preferably, the method for preparing the fermentation broth comprises the following steps:

[0029] In a fifth aspect, the present invention provides a method for preparing the above-mentioned microbial agent for preventing and controlling white rot of peanut, comprising the following steps:

[0030] (1) mixing a fermentation solution of Polysporus rosiglita, sodium alginate, bentonite, skim milk, and chitosan oligosaccharide to obtain a mixed solution;

[0031] (2) adding the mixed solution obtained in step (1) to the CaCl2 solution to carry out a curing and cross-linking reaction, washing, and drying to obtain the microbial agent.

[0032] Preferably, the specific preparation method of the microbial agent for preventing and controlling peanut white rot comprises the following steps:

[0033] (1) mixing a fermentation solution of Polysporus rosiglita, sodium alginate, bentonite, skim milk, and chitosan oligosaccharide to obtain a mixed solution;

[0034] (2) placing the CaCl2 solution on a magnetic stirrer, using a syringe to absorb the mixed solution obtained in step (1), aligning the needle vertically with the center of the CaCl2 solution surface, and slowly pushing the syringe piston at a liquid level of 15-20 cm, so that the mixed solution drips into the CaCl2 solution in the form of water drops, and the droplet falling speed is maintained at 25-30 drops / min. After 24 hours of curing and cross-linking reaction, the mixture is filtered out, rinsed with sterile saline three times, and the wet microcapsules are placed in an oven at 40°C to dry to a constant temperature, thereby obtaining the microbial agent.

[0035] The present invention is beneficial in that:

[0036] The present invention separates and screens a pink spiral Clonostachys rosea strain, which can produce spores, has good stress resistance, can survive for a long time in some extreme environments, is easy to preserve, and is very suitable for the preservation, processing and application of microbial agents.

[0037] Preparing it into a microbial agent has the following advantages:

[0038] 1. The microbial agent prepared by the present invention can improve soil fertility while preventing and controlling white rot, activate and improve the soil, and is environmentally friendly and pollution-free.

[0039] 2. The microbial agent prepared by the present invention is environmentally friendly, can achieve green prevention and control of crop diseases, can improve the quality and safety of agricultural products and protect agricultural ecological safety, is conducive to the pollution-free production of crops, and is conducive to improving the quality of crops.

[0040] 3. The microbial agent of the present invention has low production cost, can enhance the international competitiveness of agricultural products, and is easy to promote and popularize. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 The morphological characteristics of strain YB-2001 were observed; Figure A is the front of the strain, Figure B is the back of the strain, Figure C is the conidiophore, and Figure D is the conidia.

[0042] Figure 2 This is the phylogenetic tree of strain YB-2001 based on rDNA-ITS sequence homology. DETAILED DESCRIPTION

[0043] In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0044] Unless otherwise specified, the instruments and equipment involved in the following examples are all conventional instruments and equipment; unless otherwise specified, the reagents involved are all commercially available conventional reagents; unless otherwise specified, the test methods involved are all conventional methods.

[0045] Example 1: Isolation and identification of strains

[0046] (1) Strain isolation

[0047] The invention obtains a strain by separating and screening the peanut stem base from Huaizhou Family Farm in Zhengyang County, Henan Province, and the strain is named as strain YB-2001.

[0048] (2) Morphological characteristics of strains

[0049] The strain YB-2001 was inoculated on a PDA medium plate and cultured at 29°C for 5 days, and then the morphological characteristics of the strain were observed.

[0050] The formula of the PDA medium is as follows: 200 g of potato, 20 g of glucose, 15-20 g of agar, and distilled water is added to 1 L, and the medium is sterilized by high pressure at 121° C. for 30 min to obtain the PDA medium.

[0051] The morphological characteristics of the strains were observed as follows Figure 1 As shown in the figure, the colony edge of strain YB-2001 is neat, the hyphae are creeping, loose, and the color is light pink to light yellow. The hyphae of the strain have septa, and the conidiophores grow directly from the hyphae, are colorless, and have broom-like branches at the top. The conidiophores are attached to the ends of the conidiophores, which are antoflask-shaped, and the conidia are attached to the top of the conidiophores, which are long and oval.

[0052] (3) Molecular biological characteristics

[0053] The genomic DNA of strain YB-2001 was extracted and sequenced. The rDNA-ITS sequence of strain YB-2001 is shown in SEQ ID NO. 1. The DNA sequence obtained by sequencing was searched for homology with the GeneBank database using the BLAST function of NCBI. The sequence homology was calculated using MEGE software and a basic phylogenetic tree was constructed. The results are shown in Figure 2 shown.

[0054] Based on the above identification results, strain YB-2001 was identified as Clonostachys rosea, and the strain was named Clonostachys rosea. It was deposited in the General Microbiology Center of China Culture Collection on April 18, 2022, at the Institute of Microbiology, Chinese Academy of Sciences, No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, with the deposit number CGMCC No.40130.

[0055] Example 2: Preparation of Pink Spiral Polysporus Fermentation Broth

[0056] The preparation method of the pink spiral polysporus fermentation liquid comprises the following steps:

[0057] (1) Clonostachys rosea was inoculated on a PDA plate under sterile conditions, cultured at 25°C for 5 hours, and a bacterial cake was punched at the edge of the colony with a borer;

[0058] (2) Inoculate 3 bacterial cakes per 100 mL of PDB medium and culture at 28°C and 180 rpm for 3 days to obtain seed solution;

[0059] (3) 2% of the seed liquid was inoculated into the fermentation medium, and the mixture was cultured in a shaking incubator at 28° C. for 3 days. Mycelium and impurities in the medium were removed by filtration through a sterile double-layer gauze to obtain a fermentation liquid of Polysporum roseum.

[0060] The formula of the fermentation medium is (by weight percentage): 3% corn flour, 1% fish meal, 0.5% maltose, 0.1% manganese sulfate, 0.2% potassium dihydrogen phosphate, the balance is water, and the pH value is 7.0-8.0.

[0061] Example 3

[0062] An embodiment of the microbial agent for preventing and controlling peanut white rot of the present invention is a microcapsule preparation; the microbial agent comprises the following raw materials in percentage by mass: 30% fermentation liquid of pink spiral polysporus, 2% sodium alginate, 3% bentonite, 2% skim milk, 1% chitosan oligosaccharide, 3% CaCl2, and water is supplemented to 100%.

[0063] The preparation method of the microbial agent comprises the following steps:

[0064] (1) mixing a fermentation solution of Polysporus rosiglita, sodium alginate, bentonite, skim milk, and chitosan oligosaccharide to obtain a mixed solution;

[0065] (2) placing the CaCl2 solution on a magnetic stirrer, using a syringe to absorb the mixed solution obtained in step (1), aligning the needle vertically with the center of the CaCl2 solution surface, and slowly pushing the syringe piston at a liquid level of 15-20 cm, so that the mixed solution drips into the CaCl2 solution in the form of water drops, and the droplet falling speed is maintained at 25-30 drops / min. After 24 hours of curing and cross-linking reaction, the mixture is filtered out, rinsed with sterile saline three times, and the wet microcapsules are placed in an oven at 40°C to dry to a constant temperature, thereby obtaining the microbial agent.

[0066] Test Example 1: Embedding Rate Test

[0067] Under the conditions of 30% inoculation amount of the fermentation liquid of pink spiral polysporus, 3% CaCl2 concentration, and 24h cross-linking curing time, 2% sodium alginate, 3% bentonite, 2% skim milk, and 1% chitosan oligosaccharide were added respectively to obtain a microcapsule preparation (i.e., the microcapsule preparation prepared in Example 3). The embedding rate of the obtained microcapsule preparation for the strain was measured; the embedding rate was calculated according to the following formula:

[0068] Embedding rate (%) = number of viable bacteria in microcapsule preparation / number of viable bacteria administered × 100%

[0069] The method for determining the number of viable bacteria in the microcapsule preparation is as follows: take 1g of microcapsules and add 9mL of citrate buffer (0.2mol / L), vortex and shake for 10min to fully dissolve the microcapsules and release the bacteria into the solution. Uninoculated microcapsules and free bacteria are used as controls. After gradient dilution, the colonies are counted using a PDA plate.

[0070] The number of viable bacteria in the microcapsule preparation was determined to be 7.8×10 8 CFU / g; the embedding rate of the microcapsule preparation prepared in Example 3 reached 96.2%.

[0071] Test Example 2: Stability test of microbial agents

[0072] Test sample: Pink spiral polysporus fermentation liquid prepared in Example 2 (viable bacteria count 7.78×10 8 CFU / g), the pink spiral polysporus microbial agent prepared in Example 3 (the number of viable bacteria was 7.52×10 8 CFU / g).

[0073] The test sample was stored at 25° C. and the number of viable bacteria was determined by a plate spreading method after 60 days to evaluate the stability of the microbial agent prepared by the present invention.

[0074] The stability test results showed that as time went on, the number of live bacteria in the pink spiral polysporus microbial agent slowly decreased, while the number of live bacteria in the pink spiral polysporus fermentation liquid decreased rapidly, and the rate of decrease of the number of live bacteria in the pink spiral polysporus fermentation liquid was significantly higher than that of the pink spiral polysporus microbial agent. On day 0, the number of live bacteria in the pink spiral polysporus fermentation liquid was 7.78×10 8 CFU / g, the number of live bacteria of the pink spiral polysporus microbial agent was 7.52×10 8 CFU / g; after 60 days, the number of live bacteria in the fermentation liquid of Pink Spiral Polysporon was 5.02×10 5 CFU / g, the number of live bacteria of the pink spiral polysporus microbial agent was 8.55×10 7CFU / g; compared with day 0, the number of live bacteria in the pink spiral polysporus microbial agent decreased by one order of magnitude, while the number of live bacteria in the pink spiral polysporus fermentation liquid decreased by three orders of magnitude. It can be seen that the pink spiral polysporus microbial agent can improve the strain stability of pink spiral polysporus.

[0075] Test Example 3: Stress resistance test of microbial agents

[0076] Test sample: Pink spiral polysporus fermentation liquid prepared in Example 2 (viable bacteria count 7.52×10 8 CFU / g), the pink spiral polysporus microbial agent prepared in Example 3 (the number of viable bacteria was 7.78×10 8 CFU / g).

[0077] Testing process:

[0078] PD culture media (formula: 200 g potato, 20 g glucose, 17-20 g agar, 1 L water) with different NaCl concentrations (0%, 1%, 2% and 3%) and different pH values ​​(4.0, 5.0, 6.0, 7.0, 8.0, 9.0 and 10.0) were prepared respectively.

[0079] 80 μL of the test sample was spread on PD culture medium with different salt concentrations and pH values, and the number of viable bacteria was measured after 7 days to determine the salt resistance and acid-base resistance of the microbial agent.

[0080] The results of salt tolerance showed that the number of live bacteria of the pink spiral polysporus microbial agent and the pink spiral polysporus fermentation liquid was the highest after being cultured in the medium containing 1% NaCl, which was 7.88×10 8 CFU / mL, 7.56×10 8 CFU / mL, there was no significant difference between the two. However, when the NaCl concentration was increased to 2% and 3%, the number of live bacteria in the pink spiral polysporus microbial inoculant was 7.23×10 8 CFU / mL, 7.65×10 8 CFU / mL, while the number of viable bacteria in the fermentation broth of Pink Spiral Polysporon was 7.99×10 7 CFU / mL, 7.58×10 7 CFU / mL. That is, as the salt concentration increases, the number of live bacteria in the fermentation broth of Pink Spiral Polysporon is significantly lower than the number of live bacteria in the Pink Spiral Polysporon microbial agent. It can be seen that preparing Pink Spiral Polysporon into a microcapsule formulation can significantly increase the salt tolerance of Pink Spiral Polysporon.

[0081] The results of acid and alkali resistance showed that the change of medium pH affected the activity of the strain. When the pH of the medium was 7, the number of live bacteria in the pink spiral polysporon microbial agent and the pink spiral polysporon fermentation liquid was the highest, which were 4.23×10 8 CFU / mL, 4.56×10 8 CFU / mL, there was no significant difference in the number of live bacteria between the two. When the pH of the culture medium was 6, the number of live bacteria in the pink spiral polysporon microbial agent and the pink spiral polysporon fermentation liquid were 3.54×10 8 CFU / mL and 3.21×10 8 CFU / mL, the difference in the number of live bacteria between the two was not significant. When the pH of the culture medium was less than 5 or greater than 8, the number of live bacteria in the pink spiral polysporon microbial agent and the pink spiral polysporon fermentation broth was significantly reduced, indicating that the pH value of the culture medium has an important influence on the activity of the strain. In addition, when the pH of the culture medium was 5, 8, 9, and 10, the number of live bacteria in the pink spiral polysporon microbial agent was significantly higher than that in the pink spiral polysporon fermentation broth, indicating that preparing pink spiral polysporon into a microcapsule formulation can significantly increase the acid and alkali resistance of pink spiral polysporon.

[0082] Test Example 4: Test on the resistance of microbial agents to ultraviolet radiation

[0083] Test samples: the fermentation broth of pink spiral polysporus prepared in Example 2 and the pink spiral polysporus microbial agent prepared in Example 3.

[0084] Testing process:

[0085] The test samples were irradiated under a broad-wavelength ultraviolet lamp for 0h, 0.5h, 1h, 2h, 3h, 6h, 12h, and 24h, and the number of viable bacteria was determined. The test samples stored in the dark under the same conditions were used as controls to evaluate the ultraviolet radiation resistance of the pink spiral spore microbial agent.

[0086] The results of UV radiation resistance showed that the viable counts of the fermentation liquid of Pink Spiral Polysporus and the Pink Spiral Polysporus microbial agent at 0 h of UV irradiation were 7.25×10 8 CFU / g, 7.64×10 8 CFU / g; however, after 0.5 h of UV light irradiation, the number of live bacteria in the fermentation liquid of Pink Spiral Polysporon was 0, and the number of live bacteria in the Pink Spiral Polysporon microbial agent was 5.65×10 8 CFU / g. Although the number of live bacteria in the pink spiral polysporus microbial inoculant gradually decreased with the increase of UV irradiation time, the number of live bacteria in the pink spiral polysporus microbial inoculant could still reach 2.78×10 8CFU / g. This indicates that preparing pink spiral polysporus into microcapsule dosage form can significantly increase the ability of pink spiral polysporus to resist ultraviolet radiation.

[0087] Test Example 5: Test on the high temperature resistance of microbial agents

[0088] Test samples: the fermentation broth of pink spiral polysporus prepared in Example 2 and the pink spiral polysporus microbial agent prepared in Example 3.

[0089] Testing process:

[0090] The test samples were placed in incubators at 25°C, 30°C, 35°C, and 40°C for 7 days, and the number of viable bacteria was measured to evaluate the high temperature resistance.

[0091] The results of high temperature resistance showed that with the increase of culture temperature, the number of live bacteria in the pink spiral polysporon microbial agent and the pink spiral polysporon fermentation liquid gradually decreased. Among them, there was no significant difference in the number of live bacteria between the pink spiral polysporon microbial agent and the pink spiral polysporon fermentation liquid after being stored at a culture temperature of 25℃ for 7 days, which were 6.34×10 8 CFU / g, 6.02×10 8 CFU / g.

[0092] However, when the culture temperature was 30℃, 35℃, and 40℃, the number of live bacteria in the pink spiral polysporon microbial agent was significantly higher than that in the pink spiral polysporon fermentation broth. Among them, when the culture temperature was 30℃, the number of live bacteria in the pink spiral polysporon microbial agent and the pink spiral polysporon fermentation broth were 4.85×10 8 CFU / g, 4.11×10 8 CFU / g; when the culture temperature was 35℃, the number of viable bacteria in the pink spiral polysporon microbial agent and the pink spiral polysporon fermentation liquid were 2.61×10 8 CFU / g, 0.49×10 8 CFU / g; when the culture temperature is 40℃, the number of viable bacteria in the pink spiral polysporus microbial inoculant is 1.56×10 8 CFU / g, while the number of viable bacteria in the fermentation broth of Pink Spirocystis was 3.29×10 3 CFU / g. It can be seen that preparing pink spiral polysporus into microcapsule dosage form can significantly increase the high temperature resistance of pink spiral polysporus.

[0093] Test Example 6: Verification of the control effect of microbial agents on peanut white rot

[0094] The indoor control effect of the pink spiral polysporon microbial agent prepared in Example 3 on peanut white rot was determined. Four treatments were set in the pot test: (1) 0.6 g of microorganism / plant hole application; (2) 1 g of microorganism / plant hole application; (3) 240 g / L thiothiocarb 5 μL / plant hole application; (4) blank control. Peanut seeds were disinfected with 75% alcohol for 1 min, rinsed with sterile water 3 times, and germinated at 28°C for 2 days. Peanut seeds with consistent germination status were selected for planting, and 2 seeds were planted per pot. Peanut seedlings with consistent growth were selected for inoculation with the pathogen, and each peanut was inoculated with a peanut white rot fungus cake with a diameter of 5 mm. After one month, the incidence of peanut plants was investigated, the disease grade of peanuts in each treatment was recorded, and the disease index and control effect were calculated. After three months, the yield of each peanut plant was investigated.

[0095] The disease grading standards are as follows: Level 0: the plant has no symptoms; Level 1: only lesions appear at the base of the stem; Level 3: constriction symptoms appear at the base of the stem, and finally less than 1 / 3 of the plants show systemic symptoms (wilt, death, wilt, etc.); Level 5: eventually less than 2 / 3 of the plants show systemic symptoms (wilt, death, wilt, etc.); Level 7: eventually more than 2 / 3 of the plants show systemic symptoms (wilt, death, wilt, etc.); Level 9: The entire plant eventually dies.

[0096] Table 1 Results of potted plant test on pink spiral polysporus microbial agent for controlling white rot of peanut

[0097] Treatment Group Disease index Control effect (%) Yield per plant (g) Microbial agent 0.6g / strain 15.1b 67.6 11.2 Microbial agent 1g / strain 7.2c 84.5 14.0 240g / L Thifluzamide 5μL / plant 7.5c 83.9 12.8 Blank control 46.6a / 8.5

[0098] Note: Different letters after the data in the same column indicate significant differences (P<0.05) using Duncan's new multiple range test.

[0099] The results are shown in Table 1. The disease index of the microbial agent 1g / plant was 7.2, and the control effect on peanut white rot was 84.5%; the disease index of 240g / L thiofuran 5μL / plant was 7.5, and the control effect was 83.9%, and there was no significant difference between the two. In addition, the disease index and control effect of the microbial agent 0.6g / plant reached 15.1 and 67.6%, respectively. In addition, the single plant yield of the microbial agent 1g / plant was 14.0g, and the single plant yield of the blank control was 8.5g, which was 64.7% higher than the control. It can be seen that the pink spiral polysporus microbial agent has good application potential in the control of peanut white rot.

[0100] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A Clonostachys rosea, characterized in that The pink spiral Clonostachys rosea was deposited at the General Microbiology Center of the China Culture Collection Administration on April 18, 2022, at the Institute of Microbiology, Chinese Academy of Sciences, No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, with the deposit number CGMCC No.40130.

2. Use of the pink spiral spore mold as claimed in claim 1 in preventing and treating peanut white rot.

3. Use of the pink spiral polysporon as claimed in claim 1 in preparing a fungicide for preventing and treating peanut white rot.

4. A microbial agent for preventing and treating peanut white rot, characterized in that: The raw materials for preparing the microbial agent include the fermentation broth of the pink spiral polysporus according to claim 1; and the preparation method of the fermentation broth includes the following steps: (1) inoculating pink spiral polysporus on a solid culture medium for activation; inoculating and culturing in a liquid culture medium to obtain a seed solution; (2) inoculating the seed liquid obtained in step (1) into a fermentation medium for cultivation, and filtering to obtain the fermentation liquid.

5. The microbial agent for preventing and treating peanut white rot as claimed in claim 4, characterized in that: The fermentation medium comprises the following components in weight percentage: 1%-3% corn flour, 1%-2% fish meal, 0.1%-0.5% maltose, 0.1%-0.2% manganese sulfate, 0.1%-0.2% potassium dihydrogen phosphate, and the balance water.

6. The microbial agent for preventing and treating peanut white rot as claimed in claim 4, characterized in that: The raw materials for preparing the microbial agent also include at least one of sodium alginate, bentonite, skim milk, chitosan oligosaccharide and CaCl2.

7. The microbial agent for preventing and treating peanut white rot as claimed in claim 6, characterized in that: The microbial agent comprises the following raw materials in percentage by mass: 25%-30% of fermented bacterial liquid of pink spiral polysporus, 1%-2% of sodium alginate, 1%-4% of bentonite, 1%-4% of skim milk, 1%-2% of chitosan oligosaccharide, 1%-3% of CaCl2, and water is added to 100%.

8. The microbial agent for preventing and treating peanut white rot as claimed in claim 4, characterized in that: The number of live bacteria in the pink spiral polysporus fungicide is 7.0×10 8 CFU / g-7.8×10 8 CFU / g.

9. A method for preparing a microbial agent for controlling peanut white rot as claimed in any one of claims 4 to 8, characterized in that: The steps include: (1) mixing a fermentation solution of Polysporus rosiglita, sodium alginate, bentonite, skim milk, and chitosan oligosaccharide to obtain a mixed solution; (2) adding the mixed solution obtained in step (1) to the CaCl2 solution to carry out a curing and cross-linking reaction, washing, and drying to obtain the microbial agent.

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