Lactobacillus buchneri and application thereof in plant growth promotion

Abstract

The application discloses a lactobacillus buchneri and application thereof in plant growth promotion, and belongs to the technical field of microorganisms. Through 16S rRNA sequence analysis, the lactobacillus buchneri HAC1b23.7 isolated is identified as a lactobacillus, and the preservation number is CGMCC No. 28790. The fermentation liquor of the lactobacillus buchneri HAC1b23.7 strain has a broad-spectrum promoting effect on the planting and growth of crops, and can also enhance the transformation and absorption of nutrients in soil by plants. The lactobacillus buchneri HAC1b23.7 can be prepared into a microbial preparation and applied to the field of plant growth promotion, and has a wide prospect.

Description

Technical Field

[0001] This invention belongs to the field of microbial technology and relates to a strain of Lactobacillus brunelli belonging to the genus Lactobacillus, and its application in promoting crop growth. Background Technology

[0002] Microbial inoculants are commonly referred to as microbial fertilizers, microbial pesticides, and microecological preparations, depending on their specific applications. Microbial inoculants or microecological preparations play a crucial role in improving soil structure, resolving soil compaction, increasing soil fertility, enhancing plant resistance, promoting plant growth, and improving seedling survival rates. These effects are achieved through the colonization, reproduction, and transfer of functional strains on the plant surface, within the plant, or in the rhizosphere, establishing population dominance and regulating the proportion and balance of inherent microorganisms within the plant and its microenvironment. Furthermore, the metabolic products of functional strains can inhibit the activity of harmful microorganisms in the soil, reducing the damage of pathogens to plant roots. For example, Adriana Ambrosini argues that microbial inoculants are an alternative method to improve crop productivity by reducing the use of chemical fertilizers, one of the more controversial agricultural practices with environmental impacts (Ambrosini, A., R. de Souza, and LMP Passaglia, Ecological role of bacterial inoculants and their potential impact on soil microbial diversity. Plant and Soil, 2015, 400(1-2): p. 193-207.). Beneficial bacteria, collectively known as plant growth-promoting bacteria (PGPB), promote plant growth and protect plants from diseases and abiotic stresses through a variety of mechanisms. The efficiency of bacterial inoculation is related to the beneficial properties of the inoculated bacteria and the complex network of interactions occurring in the soil. Jiang Hongbo studied the effects of three AM fungi on the growth and development of dahlias, marigolds, and calendula. The results showed that AM fungi could not only improve the transplant survival rate of seedlings of these three flowers and promote plant growth and development, but also advance the flowering period, increase the number of flowers during the peak flowering period, and prolong the flowering period (Guo Shaoxia, et al. Effects of AM fungi on the growth and development of three flowers [J]. Liaoning Forestry Science and Technology, 2008(04): p.22-24+35.). Huang Pengfei's research showed that microbial inoculants can improve the absorption of nutrients by Masson pine seedlings, promote the growth of Masson pine, and improve the rhizosphere soil microecological community (Huang Pengfei. Research and application of compound microbial inoculants for Masson pine. 2012.).

[0003] Microbial fertilizers are products containing specific live microorganisms. Through the activity of these microorganisms, they increase the supply of nutrients to plants or promote plant growth, thereby increasing crop yields and improving product quality and the agricultural ecological environment. Furthermore, they also improve soil fertility, enhance plant resistance to stress, assist crops in nutrient absorption, and reduce the use of chemical fertilizers, making them increasingly important. Currently, the structure of growth-promoting fertilizer products is still dominated by chemical fertilizers, which hold an absolute market share. The variety and quantity of biological growth-promoting agents are very limited, and their market share is not high, falling far short of the requirements for green pest control and green food production. Therefore, actively screening and developing new varieties of highly efficient and low-toxicity biological growth-promoting agents is of great significance. Summary of the Invention

[0004] This invention aims to develop a broad-spectrum, multi-functional plant growth-promoting bacterium and its application in crop cultivation. To achieve the technical objective of this invention, it provides *Lactobacillus brucellosis* HAC1b23.7, and the application of microbial preparations containing *Lactobacillus brucellosis* HAC1b23.7 in promoting crop growth.

[0005] The *Lactobacillus brunetti* HAC1b23.7 described in this invention was collected from wild Artemisia argyi leaves at an altitude of 1220 meters in Xuefeng Township, Hancheng City, Shaanxi Province. Preservation information is as follows:

[0006] Classification and nomenclature: Lactobacillus buchneri;

[0007] Preservation date: October 27, 2023;

[0008] Preservation institution: China General Microbiological Culture Collection Center, China Committee on the Preservation and Management of Microbial Culture Collections;

[0009] Address of the depositary: Institute of Microbiology, Chinese Academy of Sciences, No. 3, No. 1 Beichen West Road, Chaoyang District, Beijing, China;

[0010] Accession number: CGMCC No.28790.

[0011] Furthermore, the *Lactobacillus bruneri* HAC1b23.7 described in this invention was isolated from wild Artemisia argyi leaves at an altitude of 1220 meters in Xuefeng Township, Hancheng City, Shaanxi Province. *Lactobacillus bruneri* colonies are typically white or milky white and irregularly round or irregular in shape. Colonies are usually small, generally 1–2 mm in diameter, but the specific size may vary depending on the strain. Colonies are typically dry, milky, or powdery in texture, do not produce mucus, and the colony surface is usually relatively smooth.

[0012] Furthermore, the 16S rRNA gene sequence of Lactobacillus buchneri HAC1b23.7 described in this invention has a similarity of 99.93% with strain Lentilactobacillus buchneri strain (GenBank: MT463457.1), and Lactobacillus buchneri described in this invention belongs to the genus Lactobacillus.

[0013] Furthermore, the present invention relates to a method for activating and fermenting Lactobacillus brunelli HAC1b23.7, as one of the preferred embodiments of the technical solution of the present invention.

[0014] Preferably, in the activation method provided by the present invention, the activation medium is preferably MRS medium, and the activation conditions are: 36℃, culture for 3 to 5 days.

[0015] Preferably, in the fermentation method provided by the present invention, the concentration of the Lactobacillus bromide suspension is controlled at 10. 6 The number of cells / mL was on the order of magnitude; for inoculation and fermentation, the suspension was inoculated into the fermentation medium at a volume ratio of 5%, and the fermentation conditions were: 30℃ and 120r / min shaking culture for 72h under anaerobic or hypoxic conditions.

[0016] Furthermore, the present invention, through a phosphorus solubilization test of Lactobacillus buchneri strain HAC1b23.7, found that the phosphorus solubilization capacity of Lactobacillus buchneri strain was D / d = 5.2, the phosphorus solubilization capacity was 8.7 mg / mL, and the pH was 4.8.

[0017] Furthermore, the present invention, through an ability test of Lactobacillus bruneri HAC1b23.7 to produce the plant hormone indoleacetic acid (IAA), found that the indoleacetic acid content produced by Lactobacillus bruneri HAC1b23.7 strain was 32.41 mg / mL.

[0018] Furthermore, the present invention provides a microbial preparation comprising the aforementioned *Lactobacillus brunelli* HAC1b23.7. This microbial preparation can be used to promote the growth and increase the yield of crops such as corn and leeks.

[0019] The aforementioned microbial preparations include, but are not limited to, solid or liquid preparations, such as powders or suspensions. If it is a suspension, the bacterial count of *Lactobacillus bruneri* HAC1b23.7 is preferably 3 × 10⁻⁶. 8 cfu / mL.

[0020] Compared with the prior art, the technical solution provided by the present invention has at least the following beneficial effects or advantages:

[0021] This invention isolates Lactobacillus bryonicus HAC1b23.7 from the leaves of wild Artemisia argyi at an altitude of 1220 meters. This strain has certain phosphorus-solubilizing ability and the ability to produce the plant hormone indoleacetic acid, and has multiple functions such as promoting plant growth and strengthening roots.

[0022] This invention provides a broad-spectrum, multi-effect plant growth-promoting bacterium, which can be prepared into a microbial preparation of Lactobacillus bruneri HAC1b23.7 as a fertilizer for agricultural planting, and can promote the growth and development of crops efficiently and without pollution. Attached Figure Description

[0023] Figure 1 This is a colony morphology diagram of HAC1b23.7 described in this invention after anaerobic culture on MRS medium for 2 days.

[0024] Figure 2 This is a morphological image of Lactobacillus brunetti HAC1b23.7 after anaerobic culture on MRS medium for 5 days, as described in this invention.

[0025] Figure 3 This is a scanning electron microscope image of the bacterial cells of Lactobacillus brunetti HAC1b23.7 described in this invention.

[0026] Figure 4 This is a scanning electron microscope image of the cell proliferation of Lactobacillus brunetti HAC1b23.7 described in this invention.

[0027] Figure 5 This is a Gram-stained microscopic image of Lactobacillus brunetti HAC1b23.7 as described in this invention.

[0028] Figure 6 This is a fermentation growth curve of Lactobacillus bruneri HAC1b23.7 in fermentation medium according to the present invention.

[0029] Figure 7 For the standard curve of growth hormone IAA, R 2 >0.9997.

[0030] Figure 8 This is a before-and-after comparison of the growth-promoting effect of Lactobacillus bruneri HAC1b23.7 bacterial solution on corn pot plants as described in this invention. Detailed Implementation

[0031] The technical solution of the present invention will be described below with reference to embodiments. However, the present invention is not limited to the following embodiments. Unless otherwise specified, the experimental methods and detection methods described in each embodiment are conventional methods; unless otherwise specified, the reagents and materials can be purchased commercially.

[0032] Example 1

[0033] This embodiment provides the isolation and identification of Lactobacillus brunelli HAC1b23.7.

[0034] 1. Isolation of Lactobacillus bruneri HAC1b23.7 strain

[0035] The bacterial strain was derived from endophytic bacteria on wild Artemisia argyi leaves grown at an altitude of 1220 meters in Xuefeng Township, Hancheng City, Shaanxi Province. The harvested Artemisia argyi leaves were rinsed with water, placed in a clean bench, and cut into 5cm x 5cm pieces. The leaves were then immersed in 75% ethanol for 30 seconds, rinsed four times with sterile water, and then immersed in 0.01% HgCl2 for 3 minutes. After sterilization, the leaves were cut into approximately 0.5cm lengths and inoculated into Petri dishes, with two leaves per dish and three replicates.

[0036] Lactobacillus blight strain HAC1b23.7 was isolated using both nitrogen anaerobic viable cell isolation and detection and aerobic MRS viable cell isolation and detection. The culture dishes were sealed in resealable bags to maintain an anaerobic environment and incubated at 36°C for 3–5 days. Once colonies appeared around the tissue blocks in the culture dishes, bacterial cells were picked up using an inoculation loop. The cells were streaked onto MRS medium, sealed, and marked, then incubated at 36°C using the same method. This process was repeated until colonies appeared, and single colonies were obtained. These were then cultured on MRS slant agar and finally stored at 4°C for later use.

[0037] 2. Identification of Lactobacillus bruneri HAC1b23.7 strain

[0038] This embodiment classifies and identifies *Lactobacillus buchneri* HAC1b23.7 using its 16S rRNA sequence. Those skilled in the art can easily extract the DNA of *Lactobacillus buchneri* and amplify the 16S rRNA sequence using existing techniques. The primer sequences used in the PCR amplification of the 16S rRNA gene are: 27F: (5'-AGAGTTTGATCCTGGCTCAG-3') 1492R: (5'-CGGTTACCTTGTTACGA CTT-3'), with an amplified fragment size of approximately 1200bp-1500bp. The amplified product was subjected to Sanger bidirectional sequencing, and the sequencing results were compared and analyzed on NCBI. The species with the highest homology (above 99.93%) was used to determine the species of the strain. The sequencing results showed that the 16S rRNA gene sequence of the *Lactobacillus buchneri* strain had a similarity of 99.93% to that of the strain *Lentilactobacillus buchneri* (GenBank: MT463457.1).

[0039] The gene sequence of the Lactobacillus brunelli strain has been submitted to the NCBI GenBank database. The accession number of Lactobacillus brunelli HAC1b23.7 in GenBank is OR711076.

[0040] This embodiment also classifies and identifies the Lactobacillus brunelli strain based on morphological characteristics. Figure 1 The colony morphology of *Lactobacillus bruneri* HAC1b23.7 after anaerobic culture on MRS medium for 2 days is shown. Figure 2 The image shows the cell morphology of Lactobacillus bruneri HAC1b23.7 after 5 days of fermentation culture. Figure 3 This is a scanning electron microscope image of the bacterial cells of *Lactobacillus bruneri* HAC1b23.7. When inoculated onto MRS medium, *Lactobacillus bruneri* colonies typically appear white or milky white, with irregularly round or irregular shapes; colonies are usually small, generally 1–2 mm in diameter, but the exact size may vary depending on the strain; colonies are usually dry, milky, or powdery in texture, do not produce mucus, and the colony surface is usually relatively smooth.

[0041] Based on the observation of strain morphology, culture characteristics and 16S rRNA identification results, the *Lactobacillus bucheri* described in this invention belongs to the genus *Lactobacillus*, and the inventors named it HAC1b23.7.

[0042] Example 2

[0043] This embodiment provides an optimized selection of culture media (activation medium and fermentation medium) for Lactobacillus brunelli HAC1b23.7.

[0044] The inventors added the following reagents to the basic culture medium of *Lactobacillus bruneri* HAC1b23.7 (10.0 g peptone, 10.0 g beef extract, 5.0 g yeast extract, 2.0 g diammonium hydrogen citrate, 20.0 g glucose, 18.0 g agar, 1000 mL distilled water, pH 6.2–6.6): 1.0 mL Tween-80, 5.0 g sodium acetate, 2.0 g dipotassium hydrogen phosphate, 0.58 g magnesium sulfate, and 0.25 g manganese sulfate to obtain an activation culture medium. This activation culture medium accelerated bacterial growth and increased bacterial cell count. The activation conditions for this strain were: incubation at 36°C for 3–5 days.

[0045] The fermentation medium for *Lactobacillus brucellosis* HAC1b23.7 consisted of: 12.0 g peptone, 6.0 g beef extract, 3.0 g yeast extract, 2.0 g diammonium citrate, 10.0 g glucose, 1.0 g dipotassium hydrogen phosphate, 0.5 g magnesium sulfate, and 1000 mL distilled water, with a pH of 6.2–6.6. A suspension of *Lactobacillus brucellosis* HAC1b23.7 was prepared, with the concentration controlled at 10-1. 6 The cell count was on the order of magnitude (in cells / mL). For inoculation and fermentation, the suspension was inoculated into the fermentation medium at a 5% (v / v) inoculum. The fermentation conditions for this strain were: 30°C under anaerobic or hypoxic conditions with shaking at 120 rpm for 72 h. The cell concentration after fermentation was 3 × 10⁻⁶ cells / mL. 8 cfu / mL. Figure 6 The fermentation growth curve of Lactobacillus bruneri HAC1b23.7 in fermentation medium is shown.

[0046] Example 3

[0047] This embodiment provides a phosphorus solubility test of Lactobacillus brunelli strain HAC1b23.7.

[0048] This embodiment uses the plate method to detect the phosphate-solubilizing ability of *Lactobacillus burlensis* strain. The inoculation loop is flame-ignited, and after cooling, the strain is inoculated onto chromogenic MRS solid medium and incubated at 30°C for 3 days. Colonies exhibiting a phosphate-solubilizing zone (the original medium is blue, the phosphate-solubilizing zone is pale yellow) are measured. The diameter (D) of the phosphate-solubilizing zone and the diameter (d) of the colony are obtained, and the D / d value is calculated.

[0049] The phosphate-solubilizing ability of the strains was quantitatively screened using the shake-flask method on NBRIP medium. 150 mL of NBRIP medium was added to a 250 mL Erlenmeyer flask and autoclaved at 121 °C for 20 min. The *Lactobacillus bromide* cells cultured overnight in MRS liquid medium were collected by centrifugation and resuspended in sterile water to prepare a bacterial suspension of 1 × 10⁻⁶. 7 cfu / mL. Take 2 mL of bacterial suspension and inoculate it into the sterilized NBRIP medium. Use an equal volume (2 mL) of sterile water as a control. Repeat each treatment 3 times. Then, culture in a shaker at 30℃ and 170 r / min for 7 days. Centrifuge the fermentation broth at 10000 rpm for 10 min and take the supernatant to determine the phosphorus content and pH using the molybdenum antimony colorimetric method and a pH meter, respectively.

[0050] The experimental results showed that the phosphorus solubilization capacity of this Lactobacillus brunelli was D / d = 5.2, the phosphorus solubilization capacity was 8.7 mg / mL, and the pH was 4.8.

[0051] Example 4

[0052] This embodiment provides a test of the ability of Lactobacillus brunelli HAC1b23.7 to produce the plant hormone indoleacetic acid (IAA).

[0053] PC colorimetric solution: Weigh 100mg of FeCl3 and dissolve it in 3mL of distilled water, then slowly add 4.3mL of 98% H2SO4 solution, and after cooling, make up to 10mL.

[0054] S2 colorimetric solution: Dissolve 45 mg FeCl3 in 3 mL of distilled water, then slowly add 5.8 mL of 98% H2SO4 solution, and bring the volume to 10 mL after cooling.

[0055] Lactobacillus bruneri HAC1b23.7 was cultured in MRS liquid medium for 48 h (36℃, 130 rpm). The optical density (OD600 value) of the bacterial suspension was adjusted to 0.01 using sterile water. 100 μL of the bacterial suspension was added to MRS culture medium containing 100 mg / L tryptophan (total volume 50 mL), and this process was repeated three times. A blank control experiment was also conducted, in which 100 μL of sterile water was added to the MRS culture medium. All cultures were placed in a temperature-controlled shaker, maintained at 36℃ and 130 rpm, and cultured for 5 days. After culture, 200 μL of liquid from both the culture medium and the blank control group were taken as samples and centrifuged at high speed (10000 rpm) to remove bacterial cells, obtaining the supernatant. 200 μL of Salkowski chromogenic solution was added to each supernatant. Under light-protected conditions, allow the sample to stand at room temperature and observe the color change. If all three replicates turn red, it indicates a positive reaction, meaning the bacteria can secrete IAA; the darker the color, the greater the amount of IAA secreted.

[0056] Further quantitative determination of IAA production by Lactobacillus bruneri HAC1b23.7: The culture conditions were the same as above. After centrifugation to remove bacterial cells and obtaining the supernatant, 200 μL of PC colorimetric solution and S2 colorimetric solution were added to the supernatant, and the absorbance of the color-changing solution at 530 nm was detected.

[0057] The experiment used uninoculated culture medium as a control for zeroing, and a standard curve was plotted using a standard solution containing indoleacetic acid, as shown below. Figure 7 The IAA content of the strain was calculated based on the standard curve, and the result was 32.41 mg / mL.

[0058] Example 5

[0059] This embodiment provides a method for preparing Lactobacillus brunelli HAC1b23.7 inoculum and a pot experiment on promoting maize growth.

[0060] 1. Preparation of seed solution

[0061] Lactobacillus bruneri HAC1b23.7 was inoculated into MRS liquid medium and cultured statically at 36°C for 72 h to obtain fermented Lactobacillus bruneri seed culture.

[0062] 2. At an inoculum ratio of 1:100, *Lactobacillus bruneri* seed culture was added to the culture medium and incubated at 36°C for 48 hours to obtain *Lactobacillus bruneri* HAC1b23.7 bacterial suspension. The suspension was tested and found to have an effective viable count ≥3×10⁻⁶. 8 The bacterial culture was prepared using cfu / mL as the inoculum. The culture medium consisted of 12.0 g peptone, 5.0 g yeast extract, 8.0 g molasses, and distilled water to a final volume of 1 L, at its natural pH.

[0063] 3. Test methods

[0064] A total of 100 potted plants were used in the experiment, with 25 replicates for each treatment. The treatments were as follows:

[0065] Treatment 1 used water as a blank control. 25 potted plants were tested, and the treatment time was 10 days.

[0066] Treatment 2 involved diluting Lactobacillus bromide HAC1b23.7 bacterial suspension 50 times and applying it to the roots and neck of corn seedlings. 25 pots were used in the experiment, and the treatment lasted for 10 days.

[0067] Treatment 3 involved diluting Lactobacillus bryonicus HAC1b23.7 bacterial suspension 150 times and applying it to the roots and neck of corn seedlings. 25 pots were used in the experiment, and the treatment lasted for 10 days.

[0068] Treatment 4 involved diluting Lactobacillus bryonicus HAC1b23.7 bacterial suspension 250 times and applying it to the roots and neck of corn seedlings. 25 pots were used in the experiment, and the treatment lasted for 10 days.

[0069] 4. Measurement and Statistical Analysis Methods

[0070] Statistical analysis method: SPSS data processing system was used for statistical analysis.

[0071] As can be seen from Table 1, compared with treatment 1, the values ​​of seedlings in treatment 3 increased significantly, reaching 213.32% in plant height, 187.14% in root length, and 305.65% in stem diameter. The other treatments also showed significant improvements compared with treatment 1, indicating that Lactobacillus bryonicus HAC1b23.7 played an important role in promoting the growth of maize seedlings.

[0072] Table 1. Results of different dilutions of Lactobacillus bruneri HAC1b23.7 promoting the growth of maize seedlings for 10 days.

[0073] Process 1 (CK) Process 2 (×50) Process 3 (×150) Process 4 (×250) Plant height (cm) <![CDATA[10.21±0.52 c ]]> <![CDATA[15.85±0.54 b ]]> <![CDATA[21.78±1.24 a ]]> <![CDATA[17.43±1.21 b ]]> Root length (cm) <![CDATA[15.24±1.12 c ]]> <![CDATA[22.43±0.69 c ]]> <![CDATA[28.52±1.38 a ]]> <![CDATA[19.57±1.09 c <!-- 5 -->]]> Diameter (mm) <![CDATA[5.31±0.64 b ]]> <![CDATA[9.25±1.12 b ]]> <![CDATA[16.23±0.94 a ]]> <![CDATA[11.64±0.94 b ]]>

[0074] Note: The above values ​​are the average values ​​of 25 maize plants in each treatment group, which are representative; mean ± standard deviation, different letters represent the significance level of P<0.05.

[0075] 5. Analysis of Experimental Results

[0076] Table 1 shows that application of *Lactobacillus bruneri* HAC1b23.7 bacterial solution resulted in vigorous seedling growth. To select the optimal treatment, multiple comparisons were conducted on root-dip treatments of maize seedlings under different treatments. The results showed that treatment 3 was the optimal treatment, with a statistically significant difference compared to treatment 1. The *Lactobacillus bruneri* HAC1b23.7 bacterial agent produced in this invention (effective viable count ≥3 × 10⁻⁶) 8 The cfu / mL concentration of Lactobacillus bryonicus showed a significant effect on corn seedlings. A 150-fold dilution significantly promoted root adhesion of the seedlings, while other dilutions of Lactobacillus bryonicus also promoted root adhesion of the seedlings.

[0077] Example 6

[0078] This embodiment provides a growth-promoting experiment of Lactobacillus bruneri HAC1b23.7 inoculum on leeks.

[0079] The location of this embodiment is Shangtan Village, Daquan Township, Haojiaqiao Town, Lingwu City, Ningxia Hui Autonomous Region, and the number of greenhouses is 2.

[0080] Greenhouse 1

[0081] Area: 84 meters long and 9 meters wide;

[0082] First root drenching time and dosage: October 23, 2023, 30kg;

[0083] First foliar spraying time and dosage: October 8, 2023, dilution ratio 50 times;

[0084] Second root drenching time and dosage: November 13, 2023, 30kg;

[0085] Second foliar spraying time and dosage: November 20, 2023, dilution ratio 25 times;

[0086] The third foliar spraying was carried out on November 26, 2023, with a dilution ratio of 50 times.

[0087] Greenhouse 2

[0088] Area: 58 meters long and 9 meters wide;

[0089] First root drenching time and dosage: October 23, 2023, 30kg;

[0090] First foliar spraying time and dosage: October 8, 2023, dilution ratio 50 times;

[0091] Second root drenching time and dosage: November 13, 2023, 30kg;

[0092] Second foliar spraying time and dosage: November 20, 2023, dilution ratio 25 times;

[0093] The third foliar spraying was carried out on November 26, 2023, with a dilution ratio of 50 times.

[0094] Yield: Before spraying, the total yield of the two greenhouses in the first crop of 2022 was 1260 jin; after spraying, the total yield of the two greenhouses in the first crop of 2023 was 2142 jin.

[0095] The results of the growth-promoting experiment on leeks by microbial agents showed that applying a 50-fold dilution of *Lactobacillus brucellosis* HAC1b23.7 bacterial solution resulted in a 1.7-fold increase in leek yield compared to the previous year. The produced *Lactobacillus brucellosis* HAC1b23.7 bacterial solution (effective viable count ≥3×10⁻⁶) 8 The cfu / mL concentration of Lactobacillus bromide solution showed a particularly significant yield-increasing effect in leek cultivation, resulting in a stronger flavor and improved quality. Other diluted concentrations of Lactobacillus bromide solution also promoted crop growth.

[0096] The embodiments described above are some, but not all, of the embodiments of the present invention. The detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art through related deductions and substitutions based on the inventive concept, without inventive effort, are within the scope of protection of the present invention.

Claims

1. A type of Lactobacillus brunelli, characterized in that, The Lactobacillus bruneri is Lactobacillus bruneri ( Lactobacillus buchneri HAC1b23.7 is deposited at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC No. 28790.

2. A composition comprising *Lactobacillus brunelli* as described in claim 1, characterized in that, The composition is any one of microbial agents, plant growth promoters, or fertilizers; The total viable count of Lactobacillus bucheri in the composition is not less than 3 × 10⁻⁶. 8 cfu / mL.

3. The use of the Lactobacillus buchneri according to claim 1, or the composition according to claim 2, in promoting phosphorus conversion.

4. The use of Lactobacillus buchneri as described in claim 1, or the composition as described in claim 2, in the production of plant growth regulators; The plant growth hormones include indoleacetic acid.

5. The use of the Lactobacillus buchneri according to claim 1, or the composition according to claim 2, in promoting plant growth; The plants mentioned include corn and chives.

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