Bacillus velezensis B313-6 and application thereof in inhibiting colletotrichum gloeosporioides of ginseng

Abstract

The invention relates to bacillus velezensis B313-6 and application thereof in inhibiting colletotrichum gloeosporioides of ginseng, and belongs to the technical field of agricultural microorganisms. The invention discloses bacillus velezensis B313-6, the preservation number of the bacillus velezensis B313-6 is CGMCC (China General Microbiological Culture Collection Center) No.31782, and the invention provides a preparation method of the bacillus velezensis B313-6 microbial inoculum. The bacillus velezensis B313-6 and the microbial inoculum thereof have high bacteriostatic activity on Colletotrichum panaccolica of ginseng, effectively reduce the occurrence of anthracnose of ginseng or American ginseng, are safe to the growth of ginseng or American ginseng, have no phytotoxicity, have no pollution to the environment, and can be widely applied to the field of biological preparations of ginseng or American ginseng, so that the bacillus velezensis B313-6 and the microbial inoculum thereof can be widely applied to the field of biological preparations of ginseng or American ginseng. The compound has good biopesticide development potential and application prospect in the aspect of preventing and treating anthracnose of ginseng or American ginseng, and has a certain growth promoting effect on ginseng roots.

Description

Technical Field

[0001] The invention belongs to the technical field of agricultural microorganisms, and particularly relates to Bacillus velez B313-6 and application thereof in inhibiting ginseng anthracnose bacteria. Background Art

[0002] Ginseng ( Panax ginseng ) is the Araliaceae ( Araliaceae ) Panax ginseng Panax ) plant, known as the "king of herbs" since ancient times, is a top-grade product for strengthening the body. It has been used for thousands of years. It tastes sweet and slightly bitter, and has the effects of greatly replenishing vital energy, nourishing blood, calming the mind, promoting fluid production and quenching thirst, and clearing the lungs and relieving asthma. It contains saponins, polysaccharides, volatile oils, amino acids, and polypeptides. my country's ginseng is mainly produced in Liaoning, Jilin, and Heilongjiang provinces in the northeast region. At present, ginseng cultivation is mainly based on farmland ginseng and forest ginseng. American ginseng ( Panax quiquefolium ), the main ingredients are American ginseng saponins, volatile oils, proteins, amino acids, polysaccharides, nucleic acids, peptides, vitamins and trace elements, which can effectively enhance the central nervous system, achieve the effects of calming the mind, eliminating fatigue, and enhancing memory. It can be used for symptoms such as insomnia, irritability, memory loss and Alzheimer's disease.

[0003] Ginseng or American ginseng has a long planting cycle and is susceptible to a variety of diseases during its growth period. Common pathogens that cause diseases include anthracnose ( Colletotrichum spp.)、Black spot fungus( Alternaria spp.), Rhizoctonia solani ( Rhizoctonia spp.), root rot pathogens ( Fusarium spp.), Botrytis cinerea ( Botrytis cinerea )、Embroidery rot fungus ( Cylindrocarpon spp.), etc. Anthracnose of ginseng or American ginseng is one of the main diseases of ginseng or American ginseng in Northeast China, which leads to the decline of agricultural product quality and huge economic losses.

[0004] Ginseng Anthracnose Colletotrichum panacicola ) is the dominant species of anthracnose fungi on ginseng and American ginseng. The pathogen causes anthracnose of ginseng or American ginseng, and its main occurrence sites are the leaves, stems and other parts of ginseng or American ginseng. Symptoms usually manifest as small circular spots on the leaf surface in the early stage of the disease, with yellow or brown halos on the edges. In the late stage of the disease, the spots change from yellow to brown to yellow-brown from the inside to the outside. In the later stage, it causes perforation of the leaves, and even the leaves fall off together with the petioles, eventually leading to the death or rot of the entire ginseng or American ginseng.

[0005] The biocontrol bacteria for ginseng or American ginseng anthracnose are mainly biocontrol bacteria, including Bacillus, Streptomyces, etc. In 2012, Lee et al. found that Bacillus subtilis DJ5, KC1, KC2 and KC4 had antagonistic activity against ginseng anthracnose bacteria, and the effect of preventing anthracnose bacteria after inoculation could reach 83-90%. In 2014, Ryu et al. found that Bacillus subtilis HK-CSM-1 strain can inhibit the growth of ginseng anthracnose bacteria. In 2015, Nguyen et al. found that Streptomyces A3265 showed antifungal activity against ginseng anthracnose bacteria. In 2023, Liu Ziyao et al. found that a strain of Bacillus Velezii LXS-N2 had an inhibitory effect on ginseng anthracnose bacteria.

[0006] Bacillus Velez Bacillus velezensis It belongs to the genus Bacillus of the family Bacillaceae. It has been reported to be effective against sweet potato stem rot pathogen ( Dickeya dadantii )、Tomato wilt pathogen ( Ralstonia solanacearum ), Fusarium oxysporum ( Fusarium oxysporum ) has good antibacterial activity and also has good growth-promoting ability. It is a biocontrol bacterium with great development potential. Foreign reports have shown that Bacillus Velez has a good inhibitory effect on a variety of diseases. TingHuang et al. found that Bacillus Velez BV01 has a good control effect on wheat root rot and pepper wilt, and has a broad-spectrum antibacterial property. It is a material for the research and development of biocontrol bacteria. Zhaoyu Li et al. reported that Bacillus Velez has a significant inhibitory effect on tomato gray mold. Qiu Yue in China reported that Bacillus Velez SDTB038 has a significant inhibitory effect on the pathogen of tomato neck rot root rot ( F. oxysporum f. sp. radicislycopersici , FORL) has good antibacterial activity and has a growth-promoting effect on tomato seed germination and plant growth. Studies by Li Kun, Hong Xiujie and others have shown that Bacillus Velezii TC-5 has a growth-promoting effect on rice seedlings and has an antibacterial effect on rice damping-off disease ( Fusarium oxysporum ) has excellent control effect. Yang Shengqing isolated and screened the Velez-Bacillus strain S6 from the soil of a horticultural greenhouse where tomatoes have been grown for many years. It has a good control effect on tomato early blight pathogen ( Alternaria solani )、Botrytis cinerea( Botrytis cinerea ) has a good inhibitory effect.

[0007] At present, the prevention and control of anthracnose of ginseng or American ginseng mainly relies on chemical pesticides, but pesticides have the disadvantages of easy residue and toxicity to humans and animals. Therefore, the development of green and pollution-free biocontrol agents has become the main research direction for the prevention and control of ginseng diseases in the future. Summary of the invention

[0008] The invention provides a Bacillus Velezii B313-6 and an application thereof in inhibiting ginseng anthracnose bacteria, and aims to inhibit ginseng anthracnose bacteria, prevent and treat ginseng or American ginseng anthracnose caused by ginseng anthracnose bacteria, and combine with chemical pesticide control to reduce crop pesticide residues, have a certain growth-promoting effect on American ginseng roots, and improve the quality of ginseng or American ginseng.

[0009] The technical solution adopted by the present invention is that a Bacillus Velezii ( Bacillus velezensis ) B313-6, its deposit number at the General Microbiology Center of China Microorganism Culture Collection Administration is: CGMCC No. 31782, the deposit date is August 29, 2024, and the address is: Institute of Microbiology, Chinese Academy of Sciences, No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing.

[0010] The Bacillus Velez Bacillus velezensis ) Application of B313-6 in inhibiting ginseng anthracnose bacteria.

[0011] A bacterial agent containing the Bacillus Velez B313-6.

[0012] The viable count of the bacterial agent is 10 7 CFU / mL.

[0013] The preparation method of the bacterial agent comprises the following steps: (1) Strain activation: inoculate Bacillus velezensis B313-6 on solid culture medium and culture at 28°C for 1-2 days; (2) Fermentation seed liquid culture: The activated strain was inoculated into a liquid culture medium, and cultured in a shaker at 28°C and 180 rpm for 12 h to obtain a seed liquid; (3) Fermentation of bacterial agent: The seed liquid was inoculated into the fermentation culture medium, and the culture was shaken in a shaker at 180 rpm at 28°C for 24 h to obtain the bacterial agent of Bacillus Velezii B313-6.

[0014] The solid culture medium in step (1) is: 3.0 g beef extract, 5.0 g peptone, 3.0 g yeast powder, 15.0 g agar powder, 1000 mL distilled water, pH 7.0.

[0015] The seed culture liquid medium in step (2) is: 5.0 g yeast powder, 10.0 g peptone, 10.0 g NaCl, 1000 mL distilled water, pH 7.0.

[0016] The bacterial agent formula in step (3) is: 20.0 g glucose, 20.0 g tryptone, 2.0 g KCl, 1000 mL distilled water, pH 7.0.

[0017] The inoculation amount of the seed liquid in step (3) is 2%.

[0018] The bacterial agent is used in inhibiting ginseng anthrax bacteria.

[0019] The Bacillus Velez subsp. B313-6 and its fermented liquid microbial agent provided by the present invention have a good inhibitory effect on ginseng anthracnose bacteria. In addition, the microbial agent has a good protective and therapeutic effect on ginseng anthracnose bacteria inoculated on ginseng detached leaves. The microbial agent of Bacillus Velez subsp. B313-6 provided by the present invention has a good field prevention and control effect on American ginseng anthracnose caused by ginseng anthracnose bacteria.

[0020] The beneficial effects of the present invention are: The Velez Bacillus B313-6 and the bacterial agent thereof of the present invention have good antagonistic effect on ginseng anthracnose bacteria, and have good inhibitory effect on ginseng anthracnose bacteria in ginseng detached leaf inoculation. It promotes the reduction of the use of chemical pesticides, is conducive to reducing the residual amount of pesticides in ginseng, is safe for the growth of American ginseng without pesticide damage, is non-toxic to humans and animals, does not pollute the environment, has a certain growth-promoting effect on American ginseng roots, and has good application development prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The morphological diagram of the Bacillus Velezii B313-6 strain of the present invention, wherein A: colony morphology on NA plate; B: single colony morphology on NA plate; C: Gram staining result of B313-6 strain, scale bar = 10 μm; Figure 2 : This is a graph showing the antibacterial activity of the Velez Bacillus B313-6 strain of the present invention, wherein A: the inhibitory effect of the Velez Bacillus B313-6 strain on the colony growth of ginseng anthracnose bacteria; B: the mycelial morphology of ginseng anthracnose bacteria hyphae under the inhibitory effect of the Velez Bacillus B313-6 strain; C: the normal mycelial morphology of ginseng anthracnose bacteria bar=10μm; Figure 3 The present invention is a diagram of the in vitro ginseng leaves inoculated with the Velez subtilis B313-6 strain, wherein A: the therapeutic effect of water treatment on the in vitro ginseng leaves inoculated with ginseng anthracnose bacteria; B: 10 7 CFU / mL Velez subtilis B313-6 inoculant against ginseng leaves inoculated with ginseng anthracnose pathogen; C: The protective effect of water treatment on ginseng leaves inoculated with ginseng anthracnose pathogen; D: 10 7 The protective effect of CFU / mL Bacillus Velezii B313-6 inoculant on ginseng detached leaves inoculated with ginseng anthracnose pathogen; Figure 4This is a field control effect diagram of the Velez Bacillus B313-6 bacterial agent of the present invention on ginseng anthracnose bacteria, wherein A, B, C, D are water controls; E, F, G, H are 10 7 Field control effect of CFU / mL Bacillus Velezii B313-6 on ginseng anthracnose pathogen; Figure 5 The figure is the effect of the Velez Bacillus B313-6 of the present invention on the agronomic traits of 2-year-old American ginseng that has naturally developed anthrax, wherein A and B: the effect of clean water on the agronomic traits of 2-year-old American ginseng; C and D: 10 7 Effect of CFU / mL Bacillus Velezii B313-6 on agronomic traits of two-year-old American ginseng. DETAILED DESCRIPTION

[0022] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention. Without departing from the spirit and essence of the present invention, modifications or substitutions made to the methods, steps or conditions of the present invention all belong to the scope of the present invention.

[0023] Unless otherwise specified, the technical means used in the examples are conventional means well known to those skilled in the art.

[0024] Example 1 Isolation, Screening and Identification of Bacillus Velezii B313-6 Strain 1.1 Isolation of bacterial strains The plate dilution separation method was used to separate the samples collected from the ginseng rhizosphere soil. 3 g of soil sample was added to 30 mL of sterile water and shaken at 180 r / min and 28°C for 30 min before being taken out for use. The soil suspension was diluted to 10% with sterile water under sterile conditions. -4 , 10 -5 , 10 -6 Three concentration gradients. Take 100 μL and apply it on the surface of NA medium in sequence. Set 3 replicates for each treatment and culture in a 28℃ constant temperature incubator for 48 h. Observe regularly during the culture period, select the dominant bacterial colonies for purification, and save for later use.

[0025] Beef extract peptone (NA) medium: beef extract 3.0g, peptone 5.0g, yeast powder 3.0g, agar powder 15.0g, distilled water 1000mL, pH 7.0-7.2.

[0026] 1.2 Screening and acquisition of Bacillus velezinii B313-6 strain Initial screening: The plate confrontation method was used to screen the antagonism of the bacterial strains isolated and purified in 1.1. Use a puncher with an inner diameter of 8 mm to punch the activated pathogens and place them in the center of the PDA plate. Use a puncher (diameter 8 mm) to punch holes on both sides 2.2 cm away from the center of the plate, and use a pipette to draw 20 μL of the biocontrol bacteria solution into the holes. Set up 3 replicates for each treatment, measure the width of the inhibition zone after culturing at 25℃ for 7 days, and save the strains with antagonistic effects for later use.

[0027] PDA medium formula: 200.0 g potato, 20.0 g glucose, 15.0 g agar, 1000 mL distilled water.

[0028] Rescreening: The filter paper method was used to activate the antagonistic strains obtained in the initial screening on beef extract peptone solid medium for 48 h, and the single colony was taken in the seed culture solution of the bacterial lawn, and cultured at 28°C and 180 r / min for 12 h as the seed solution. An 8 mm bacterial cake was taken from the edge of the YL2-2 colony and placed in the center of the blank PDA plate. Sterile filter paper was placed 2.2 cm away from both sides of the bacterial cake. 10 μL of biocontrol bacterial suspension was dripped on each filter paper, and the filter paper was sealed after the bacterial solution was completely absorbed. The culture was carried out at a constant temperature of 25°C for 7 days, and each treatment was repeated 3 times to calculate the inhibition rate. The target strain B313-6 was obtained.

[0029] Beef extract peptone solid culture medium formula: beef extract 3.0g, peptone 5.0g, yeast powder 3.0g, agar powder 15.0g, distilled water 1000 mL, pH 7.0.

[0030] The liquid culture medium formula for strain fermentation seed culture is: yeast powder 5.0g, peptone 10.0g, NaCl 10.0g, distilled water 1000mL, pH7.0.

[0031] 1.3 Identification of Bacillus velezinii B313-6 The morphological observation results showed that strain B313-6 formed white colonies on NA medium, which were opaque and had irregular colony edges. The B313-6 strain was Gram-positive and the cells were rod-shaped, such as Figure 1 As shown. The starch hydrolysis, gelatin liquefaction, VP test, nitrate reduction and other reactions of strain B313-6 were positive; the malonate and fluorescence tests were negative. 16S r DNA and gyrA, gyrB Sequence analysis results showed that the 16S rDNA and gyrA, gyrB The sequence has a high similarity of 99% with the reported Bacillus Velezii. In summary, strain B313-6 was identified as Bacillus Velezii ( Bacillus velezensis ).

[0032] Example 2 Preparation of Bacillus Velezii B313-6 bacterial agent (1) Strain activation: inoculate Bacillus velezensis B313-6 on solid culture medium and culture at 28°C for 1-2 days; (2) Fermentation seed culture: The activated strain was inoculated into a liquid culture medium and cultured in a shaker at 28°C and 180 rpm for 12 h to obtain a seed solution. (3) Fermentation of inoculum: The above seed solution was inoculated into the fermentation medium at a 2% inoculation rate, and cultured in a shaker at 180 rpm for 24 h at 28°C to obtain the inoculum of Bacillus Velezii B313-6 (the number of viable cells was about 10 7 CFU / mL).

[0033] The solid culture medium formula for strain activation culture is: 3.0 g beef extract, 5.0 g peptone, 3.0 g yeast powder, 15.0 g agar powder, 1000 mL distilled water, pH 7.0.

[0034] The formula of liquid culture medium for strain fermentation seed culture is: yeast powder 5.0g, peptone 10.0g, NaCl 10.0g, distilled water 1000mL, pH7.0.

[0035] The formula of the bacterial fermentation culture medium is: 20.0 g glucose, 20.0 g tryptone, 2.0 g KCl, 1000 mL distilled water, pH 7.0.

[0036] Example 3 Determination of the antibacterial activity of Bacillus velezinsis B313-6 against ginseng anthracnose The plate confrontation culture method was used to determine the antagonistic effect of Bacillus Velezii B313-6 on ginseng anthracnose bacteria: the activated ginseng anthracnose bacteria colonies were made into bacterial cakes of corresponding sizes using an 8 mm diameter puncher, and aseptically inoculated into the center of a PDA plate (90 mm in diameter). At the same time, a 8 mm diameter puncher was used to punch holes (8 mm in diameter) symmetrically on both sides at a distance of 25 mm from the center. The strain B313-6 was made into a bacterial suspension (concentration of about 10 7 CFU / mL), 20 μL of bacterial suspension was inoculated in each well as the treatment group; the target bacteria were inoculated only as the control group, and 20 μL of sterile water was inoculated in the holes of the control group. Each treatment was repeated 3 times and cultured in a 25°C constant temperature incubator for 7 days. When the pathogen colonies in the control group were full of the plate, the diameter of the pathogen colonies in the treatment group was measured (unit: mm), and the inhibition rate was calculated according to the following formula. The experiment was repeated 3 times and the results were averaged.

[0037] Inhibition rate (%) = [(control diameter - treatment diameter) / control diameter] × 100.

[0038] Note: The control diameter is the diameter of the pathogen colony in the control group; the treatment diameter is the diameter of the pathogen colony in the treatment group.

[0039] Preparation method of potato glucose agar PDA culture medium: weigh 200.0 g of peeled potatoes and 20.0 g of glucose, heat in a boiling water bath for 20 min, filter with gauze, adjust the solution to pH 7.0, add 15.0 g of agar powder, melt and make up to 1000 mL, and package and sterilize with wet heat (121°C, 30 min).

[0040] The preparation method of the bacterial suspension for inoculation on the plate is as follows: the preserved Bacillus Velezii B313-6 strain is activated by streaking on the plate for 1 to 2 days, a single bacterial colony is taken with an inoculation loop, inoculated into a 50 mL conical flask containing 20 mL LB liquid culture medium, and cultured in a shaking incubator at 180 r / min and 28°C for 12 hours to prepare a suspension with a concentration of about 10 7 CFU / mL bacterial suspension. LB liquid medium formula: yeast powder 5.0 g, peptone 10.0 g, NaCl 10.0 g, distilled water 1000 mL, pH 7.0. The results are shown in Table 1. Table 1 Inhibition rate of Bacillus velez B313-6 against ginseng anthracnose pathogens Serial number Pathogens Antibacterial rate (%) 1 94.62±1.08 The inhibition rate of B313-6 on the mycelial growth of ginseng anthracnose pathogens reached 94.62%, reflecting that the Bacillus Velezii B313-6 strain had a significant inhibitory effect on the growth of ginseng anthracnose pathogens. Figure 2 shown.

[0041] Example 4 Protective and therapeutic effects of Bacillus Velezii B313-6 on detached ginseng leaves inoculated with ginseng anthracnose Select healthy and mature leaves of basically the same size and growth, disinfect the surface with 75% alcohol, dry them, put them in a sterile tray covered with sterilized gauze, and soak the gauze with distilled water. A total of 3 treatment groups were set up. Use a handheld sprayer to spray different concentrations of biocontrol agents on the leaves. Inoculate the bacterial cake of ginseng anthracnose bacteria on the treated leaves. The leaves in the treatment group were inoculated with the bacterial cake of ginseng anthracnose bacteria 24 hours before spraying the bacterial agent, and the leaves in the protection group were inoculated with the bacterial cake 24 hours after spraying the bacterial agent. The control group was treated with clean water. The length of the lesion was measured by the cross method, and the lesion area was calculated using the ellipse formula. Lesion area (mm 2 ) = 1 / 4 × π × long diameter × short diameter. The results of the experimental study on the control effect of Bacillus Velezii B313-6 on detached ginseng leaves are shown in Figure 3 and Table 2.

[0042] Table 2 The protective and therapeutic effects of Bacillus Velezii B313-6 on detached ginseng leaves inoculated with ginseng anthracnose pathogens

[0043] Depend on Figure 3 It can be seen that the B313-6 agent has a certain preventive effect on ginseng anthracnose pathogens under different treatments. The lesion area of ​​the protection group is 1.24 cm 2 The inhibition rate reached 63.59% (Table 2), indicating that strain B313-6 has a protective effect against ginseng anthracnose. All ginseng leaves in the treatment group showed different degrees of lesions. The area of ​​lesions after treatment with Bacillus Velezii B313-6 was 1.25 cm 2 The inhibition rate was 41.37% (Table 2). Figure 3 It can be seen that the strain B313-6 has a therapeutic effect on ginseng anthracnose bacteria.

[0044] Example 5 Field control effect of Bacillus Velezii B313-6 on anthracnose of American ginseng caused by anthracnose pathogens In Yangcha Village, Ji'an City, Jilin Province (301.7 meters above sea level), a 2-year-old American ginseng field with a high incidence of anthracnose was selected. After the leaves of American ginseng became diseased naturally in the field, the pathogen was identified as ginseng anthracnose. The B313-6 bacterial agent (10 7 CFU / mL) was sprayed on the leaves, and water was sprayed on the leaves as a blank control. The second and third foliar sprays were carried out on the 10th and 20th days after the first foliar spray, respectively. After each foliar spray, the leaf disease grade was investigated, and the disease index and control effect were calculated. The foliar control effect of Bacillus Velezii B313-6 10 days after the third foliar spray was as follows Figure 4 , Table 3.

[0045] Table 3 Field inhibitory effect of Bacillus Velezii B313-6 on ginseng anthracnose pathogens

[0046] The control efficiency of Bacillus Velezii B313-6 after the first foliar spray was 75.21%, the control efficiency after the second foliar spray was 76.97%, and the control efficiency after the third foliar spray was 68.19%. The survey results showed that the biocontrol strain B313-6 had a good field control effect on the anthracnose of American ginseng caused by ginseng anthracnose pathogens.

[0047] Example 6 Effects of Bacillus Velezii B313-6 on agronomic traits of 2-year-old American ginseng with high incidence of anthracnose In Yangcha Village, Ji'an City, Jilin Province (301.7 meters above sea level), a 2-year-old American ginseng field with a high incidence of anthracnose was selected. The pathogen was identified as ginseng anthracnose. During its growth period, from June to July, the B313-6 bacterial agent (10 7 CFU / mL) was sprayed on the leaves of American ginseng. The spraying was carried out four times, with an interval of 10 days each time. In September, the plant height, root length, root fresh weight and stem and leaf fresh weight of American ginseng were measured. Figure 5 , when the same planting area of ​​American ginseng was used, it was found that there were 10 plants of 2-year-old American ginseng treated with B313-6 in the continuous cropping land, while only 3 plants were left in the same area of ​​the clear water control, and the other American ginseng plants had all rotted. The average plant height of the 2-year-old American ginseng treated with B313-6 was 27.50 cm, an increase of 9.69% compared with the clear water control; the average root length of the 2-year-old American ginseng treated with B313-6 was 15.13 cm, an increase of 11.25% compared with the clear water control; the fresh weight of the stems and leaves of the treatment group was 11.13 g, an increase of 9.87% compared with the clear water control; the fresh weight of the roots of the treatment group was 44.67 g, an increase of 38.73% compared with the clear water control.

[0048] Table 4 Effects of Bacillus Velezii B313-6 on agronomic traits of 2-year-old American ginseng infected with anthracnose deal with Plant height (cm) Root length (cm) Fresh weight of stems and leaves (g) Root fresh weight (g) B313-6 bacterial agent 27.50±0.15 15.13±1.58 11.13±2.33 44.67±6.26 CK 25.07±0.96 13.60±1.27 10.13±3.32 32.20±2.00 The results showed that the biocontrol agent B313-6 can effectively promote the growth of roots and leaves of American ginseng, and has a certain growth-promoting effect.

[0049] Although the present invention has been described in detail above with general descriptions and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements may be made based on the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection claimed by the present invention.

Claims

1. A Bacillus Velezii ( Bacillus velezensis )B313-6, characterized in that: Its deposit number at the General Microbiology Center of China Microorganism Culture Collection Administration is: CGMCC No. 31782, the deposit date is August 29, 2024, and the address is: Institute of Microbiology, Chinese Academy of Sciences, No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing.

2. The Bacillus Velezii as claimed in claim 1 ( Bacillus velezensis ) Application of B313-6 in inhibiting ginseng anthracnose bacteria.

3. A bacterial agent containing the Bacillus Velezii B313-6 as claimed in claim 1.

4. The bacterial agent according to claim 3, characterized in that The viable count of the bacterial agent is 10 7 CFU / mL.

5. The method for preparing the bacterial agent according to claim 3 or 4, characterized in that: The following steps are involved: (1) Strain activation: inoculate Bacillus velezensis B313-6 on solid culture medium and culture at 28°C for 1-2 days; (2) Fermentation seed liquid culture: The activated strain was inoculated into a liquid culture medium, and cultured in a shaker at 180 rpm at 28°C for 12 h to obtain a seed liquid; (3) Fermentation of bacterial agent: The seed liquid was inoculated into the fermentation culture medium, and the culture was shaken in a shaker at 180 rpm at 28°C for 24 h to obtain the bacterial agent of Bacillus Velezii B313-6.

6. The preparation method according to claim 5, characterized in that: The solid culture medium in step (1) is: 3.0 g beef extract, 5.0 g peptone, 3.0 g yeast powder, 15.0 g agar powder, 1000 mL distilled water, pH 7.

0.

7. The preparation method according to claim 5, characterized in that: The seed culture liquid medium in step (2) is: 5.0 g yeast powder, 10.0 g peptone, 10.0 g NaCl, 1000 mL distilled water, pH 7.

0.

8. The preparation method according to claim 5, characterized in that: The bacterial agent formula in step (3) is: 20.0 g glucose, 20.0 g tryptone, 2.0 g KCl, 1000 mL distilled water, pH 7.

0.

9. The preparation method according to claim 5, characterized in that: The inoculation amount of the seed liquid in step (3) is 2%.

10. Use of the bacterial agent as claimed in claim 3 or 4 in inhibiting ginseng anthracnose bacteria.

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