A bacillus tequilensis and use thereof

Abstract

The application discloses Bacillus tequilensis and application thereof, and belongs to the technical field of microorganisms. The Bacillus tequilensis is Bacillus tequilensis GXL-2p which is preserved in the China Center for Type Culture Collection of Wuhan University on October 28, 2025, and the preservation number is CCTCC NO: M 20252363. The application has the functions of biocontrol and growth promotion. On one hand, the application can be used as a biocontrol bacterium for preventing and controlling root rot and leaf spot and the like; on the other hand, the application can also be used as an important plant probiotic for assisting crops in resisting stress, and the application is especially prominent in the resistance of paddy rice, corn, wheat and the like under salt stress, and is helpful to improving the planting benefits of the crops on saline-alkali land.

Description

Technical Field

[0001] This invention belongs to the field of microbial technology, specifically relating to a type of Bacillus tekirae and its applications. Background Technology

[0002] Throughout a plant's life cycle, various adverse environmental factors, such as high salinity, high temperature, drought, ultraviolet radiation, and crop diseases, can severely impact crop quality and yield. Among these, high salinity stress and crop diseases are widely recognized as having the most serious negative impacts on crop yield.

[0003] Rice, corn, and wheat, as major global food crops, are generally quite sensitive to high salt abiotic stress and diseases.

[0004] Studies have shown that the interaction between plants and microorganisms plays a crucial role in plant nutrient absorption, growth and development, tolerance to various stresses, and disease resistance. It also has advantages such as being environmentally friendly, economically feasible, and sustainable, making it an important supplementary method to crop breeding and has attracted widespread attention.

[0005] Therefore, researching and developing microbial products that can effectively suppress crop diseases and reduce the amount and dependence on chemical pesticides, while creating microbial strains that can significantly alleviate plant salt stress, is of great practical significance for improving crop yield and quality.

[0006] In view of this, a strain of Bacillus tekirae and its application were designed to solve the above problems. Summary of the Invention

[0007] To address the problems mentioned in the background section, this invention provides a Bacillus tergentii strain and its applications, which possess both biocontrol and growth-promoting functions.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a Bacillus tequilensis, wherein the Bacillus tequilensis is Bacillus tequilensis GXL-2p, which was deposited on October 28, 2025, at the China Center for Type Culture Collection of Wuhan University, Bayi Road, Wuchang District, Wuhan City, Hubei Province, with accession number CCTCC NO: M 20252363.

[0009] Furthermore, the 16S rDNA sequence of Bacillus tequilensis GXL-2p is shown in SEQ ID NO. 3.

[0010] Application of a type of Bacillus tekiria in the control of crop root rot and leaf spot.

[0011] Furthermore, the pathogens of the crop root rot and leaf spot are one or more of the following: Alternaria solanacea, Pseudomonas pilosa, Fusarium moniliforme, Rhizoctonia solani, Fusarium oxysporum, Botrytis cinerea, Aspergillus flavus, and Phytophthora capsici.

[0012] Application of a type of Bacillus tekirae in assisting crop stress resistance.

[0013] Furthermore, the crop is one or more of rice, corn, and wheat.

[0014] Furthermore, the resistance is salt stress resistance.

[0015] Furthermore, the method of assisting crops in resisting stress is to add a suspension of Bacillus equilensis GXL-2p.

[0016] Furthermore, the preparation steps of the Bacillus tequilensis GXL-2p bacterial suspension include: Using a sterile pipette tip, aspirate 100-200 μL of Bacillus tequilensis GXL-2p from a glycerol tube and transfer it onto LB solid medium. Spread the medium using the continuous streak method and incubate at 30 °C for 1-2 days to activate Bacillus tequilensis GXL-2p on the LB solid medium. Pick a single colony from the plate and transfer it to LB liquid medium. Place the medium in a constant temperature shaker and incubate overnight at 37 ℃ and 180 rmp until the bacterial solution becomes turbid. This allows Bacillus equilensis GXL-2p to be propagated in LB liquid medium. The turbid bacterial suspension with OD600≈1.0 was centrifuged at 5000 rpm at 4 ℃ for 10 min, the supernatant was discarded, a certain volume of culture medium was added to resuspend the bacterial suspension, and the bacterial suspension was diluted to OD600=1.0.

[0017] Furthermore, the preparation steps of the LB culture medium include: 5.0 g / L tryptone, 3.0 g / L yeast, 0.87 g / L calcium chloride, distilled water to a final volume of 1 L, autoclaved at 121℃ for 20 min; For solid culture media, 15.0 g / L of agar powder is added.

[0018] Compared with the prior art, the beneficial effects of the present invention are: This invention, *Bacillus tequilensis* GXL-2p, significantly inhibits the growth and reproduction of at least eight common pathogens causing root rot and leaf spot diseases in crops, including *Alternaria alternata*, *Pseudomonas aeruginosa*, *Fusarium moniliforme*, *Rhizoctonia solani*, *Fusarium oxysporum*, *Botrytis cinerea*, *Aspergillus flavus*, and *Phytophthora capsici*. Simultaneously, it assists plants in resisting salt stress and significantly increases plant biomass under stress conditions. In other words, it possesses both biocontrol and growth-promoting functions. On the one hand, it can serve as a biocontrol agent for controlling various diseases such as root rot and leaf spot; on the other hand, it can also act as an important plant probiotic to assist crops in resisting stress. It is particularly effective in improving the resistance of field crops such as rice, corn, and wheat under salt stress, thus contributing to the improved planting efficiency of these crops in saline-alkali soils. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the colony of Bacillus tequilensis GXL-2p of the present invention; Figure 2 This is a schematic diagram of Gram staining of Bacillus tequilensis GXL-2p according to the present invention; Figure 3 This is a schematic diagram of the comparative analysis results of Bacillus tequilensis GXL-2p on the Ezbiocloud website. Figure 4 This is a schematic diagram of the 16S phylogenetic tree of Bacillus tequilensis GXL-2p of the present invention; Figure 5 This is a schematic diagram illustrating the results of Bacillus tequilensis GXL-2p inhibiting the growth of various crop pathogenic microorganisms according to the present invention; Figure 6 This diagram illustrates the effects of Bacillus tequilensis GXL-2p on rice plant growth, as described in this invention. In this diagram, A represents no salt stress and no bacterial infection; B represents no salt stress and Bacillus tequilensis GXL-2p; C represents 100 mM NaCl stress treatment and no bacterial infection; and D represents 100 mM NaCl stress treatment and Bacillus tequilensis GXL-2p. Figure 7This is a schematic diagram showing the results of measuring growth indicators of rice under salt stress using Bacillus tequilensis GXL-2p, as described in this invention. In the diagram, A represents the statistical results of rice plant height, B represents the statistical results of rice root length, C and D represent the statistical results of fresh weight and dry weight of the aboveground parts of rice, respectively, and E and F represent the statistical results of fresh weight and dry weight of rice roots, respectively. Figure 8 This diagram illustrates the effect of Bacillus tequilensis GXL-2p on maize plant growth. CK represents a suspension of Bacillus tequilensis GXL-2p without salt or Bacillus tequilensis GXL-2p; CK0 represents a suspension of Bacillus tequilensis GXL-2p with salt but without salt; and B6 represents a suspension with salt but with 1×10⁻⁶ Bacillus tequilensis GXL-2p. 6 Bacillus tequilensis GXL-2p bacterial suspension at CFU / g, B7 is salted but with 1×10⁻⁶ added. 7 Bacillus tequilensis GXL-2p bacterial suspension at CFU / g, B8 is salted but with 1×10⁻⁶ added. 8 Bacillus tequilensis GXL-2p bacterial suspension at CFU / g, B9 is salted but with 1×10⁻⁶ added. 9 CFU / g of Bacillus tequilensis GXL-2p bacterial suspension; Figure 9 This diagram illustrates the determination of growth indicators of maize under salt stress using Bacillus tequilensis GXL-2p, as described in this invention. CK represents a suspension of Bacillus tequilensis GXL-2p without salt or Bacillus tequilensis GXL-2p; CK0 represents a suspension of Bacillus tequilensis GXL-2p with salt but without salt; and B6 represents a suspension with salt but with the addition of 1×10⁻⁶ Bacillus tequilensis GXL-2p. 6 Bacillus equilensis GXL-2p bacterial suspension at CFU / g, B7 is salted but with 1×10⁻⁶ added. 7 Bacillus tequilensis GXL-2p bacterial suspension at CFU / g, B8 is salted but with 1×10⁻⁶ added. 8Bacillus tequilensis GXL-2p bacterial suspension at CFU / g, B9 is salted but with 1×10⁻⁶ added. 9 CFU / g of Bacillus tequilensis GXL-2p bacterial suspension; Figure 10 This diagram illustrates the effect of Bacillus tequilensis GXL-2p on wheat plant growth. CK represents a suspension of Bacillus tequilensis GXL-2p without salt or Bacillus tequilensis GXL-2p; CK0 represents a suspension of Bacillus tequilensis GXL-2p with salt but without salt; and B6 represents a suspension with salt but with 1×10⁻⁶ added. 6 Bacillus tequilensis GXL-2p bacterial suspension at CFU / g, B7 is salted but with 1×10⁻⁶ added. 7 Bacillus tequilensis GXL-2p bacterial suspension at CFU / g, B8 is salted but with 1×10⁻⁶ added. 8 Bacillus tequilensis GXL-2p bacterial suspension at CFU / g, B9 is salted but with 1×10⁻⁶ added. 9 CFU / g of Bacillus tequilensis GXL-2p bacterial suspension; Figure 11 This diagram illustrates the determination of growth indicators of wheat under salt stress using Bacillus tequilensis GXL-2p, as described in this invention. CK represents a suspension of Bacillus tequilensis GXL-2p without salt or Bacillus tequilensis GXL-2p; CK0 represents a suspension of Bacillus tequilensis GXL-2p with salt but without salt; and B6 represents a suspension with salt but with the addition of 1×10⁻⁶ Bacillus tequilensis GXL-2p. 6 Bacillus equilensis GXL-2p bacterial suspension at CFU / g, B7 is salted but with 1×10⁻⁶ added. 7 Bacillus tequilensis GXL-2p bacterial suspension at CFU / g, B8 is salted but with 1×10⁻⁶ added. 8Bacillus tequilensis GXL-2p bacterial suspension at CFU / g, B9 is salted but with 1×10⁻⁶ added. 9 CFU / g of Bacillus tequilensis GXL-2p bacterial suspension. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] 1. Isolation and screening of Bacillus tequilensis GXL-2p Bacillus tequilensis GXL-2p was obtained by culturing, isolating, and purifying it in saline-alkali soil in Tianjin Binhai New Area. Separation and screening process: Crop growth-promoting microorganisms with significant salt tolerance and growth-promoting effects were isolated and screened using common bacterial culture and identification methods (Dong Xiuzhu, Zhou Yuguang, Zhu Honghui et al., eds. (2023) Handbook of Systematic Classification and Identification of Common Bacteria and Archaea). Soil samples were selected from saline-alkali land in Binhai New Area, Tianjin. Multiple samples were collected using mixed sampling. Stones and dead branches were removed, and the samples were placed in sterile self-sealing bags, refrigerated at 4℃, and brought back for processing within 24 hours. Weigh 10 g of soil sample, add 90 mL of sterile physiological saline (0.9% NaCl), place on a shaker at 180 rpm and 30 ℃ for 30 min, and prepare 10 -1 Soil suspension; Take 1 mL of soil suspension and add 9 mL of sterile water, then dilute to 10 mL. -2 10 -3 10 -4 10 -5 10 -6 ; Using beef extract peptone NA medium as the basal medium, NA plates with 3%, 5%, 7%, and 9% NaCl were prepared. 0.2 mL of bacterial suspension was taken from each dilution and spread onto the plate to prepare selective medium with added NaCl. The plates were incubated at 30 °C for 24-48 h. The plates with the highest salt concentration that produced colonies were selected. Single colonies with different colors, sizes, edges, and glosses were picked and purified by streak plating in four zones for 2-3 generations to ensure pure culture. The culture was then stored in slant agar / glycerol tubes. Prepare NB liquid culture medium containing 0%, 3%, 5%, 7%, 9%, 11%, and 13% NaCl, inoculate the test strains, and culture in a shaker at 30℃ for 24-48 hours. Observe the turbidity and measure OD600. Retain strains that can grow in ≥5% NaCl as candidate crop growth-promoting microorganisms with salt tolerance and growth-promoting effects, and store them in glycerol at -80℃.

[0022] 2. Biological characteristics of Bacillus tequilensis GXL-2p Single colonies were isolated and purified using the streak plate method, and the morphological characteristics of single bacterial colonies were observed and recorded. Prepare a smear from a small amount of bacterial culture and stain it with Gram stain. The morphological observation results of Bacillus equilensis GXL-2p using optical microscopy to observe individual bacterial morphology and staining characteristics are attached. Figure 1 and attached Figure 2 As shown, the results indicate that on LB plates, the colonies of this strain are pale yellow, smooth and moist, with irregular edges, opaque, and Gram-positive. The bacterial cells are short rod-shaped. Based on the above characteristics, it is preliminarily determined that this strain belongs to the genus Bacillus.

[0023] 3. Molecular biological identification information and phylogenetic tree construction of Bacillus tequilensis GXL-2p Genomic DNA of Bacillus tekirae was extracted using a rapid bacterial DNA extraction kit (Tiangen DP304, Tiangen Biotech (Beijing) Co., Ltd.); PCR amplification was performed using universal primers 27F and 1541R for bacterial 16S rDNA. The amplification products were sent to Shanghai Sangon Biotech Co., Ltd. for sequencing. The sequence of primer 27F is shown in SEQ ID NO.1; The sequence of primer 1541R is shown in SEQ ID NO.2; The sequencing sequence of the amplified product is shown in SEQ ID NO.3; The sequencing sequences of the amplified products were compared and analyzed with the type species of various bacteria on the bacterial taxonomy and identification standards website (https: / / www.ezbiocloud.net / ). The results are attached. Figure 3 As shown, strain GXL-2p is most closely related to Bacillustequilensis KCTC 13622ᵀ in terms of evolution; Simultaneously, phylogenetic analysis was constructed using the Maximum Likelihood Estimate method on MEGA 11.0, with Query Cover value of 100%, E value of 0.0, and Per. Ident value of 100%. Tree analysis was performed, and the results are attached. Figure 4 As shown, this sequence clusters on the same branch as the strain Bacillus tequilensis KCTC 13622ᵀ, whose species information is already known, indicating that they are most closely related. Based on the above, strain GXL-2p can be identified as Bacillus tequilensis and named Bacillus tequilensis GXL-2p; The strain was deposited at the China Center for Type Culture Collection, Wuhan University, on October 28, 2025, with accession number CCTCC NO: M 20252363.

[0024] 1. Preparation of LB medium 5.0 g / L tryptone, 3.0 g / L yeast, 0.87 g / L calcium chloride, distilled water to a final volume of 1 L, autoclaved at 121℃ for 20 min; For solid culture media, 15.0 g / L of agar powder is added.

[0025] 2. Preparation of Bacillus tequilensis GXL-2p bacterial suspension Using a sterile pipette tip, aspirate 100-200 μL of Bacillus tequilensis GXL-2p from a glycerol tube and transfer it onto LB solid medium. Spread the medium using the continuous streak method and incubate at 30 °C for 1-2 days to activate Bacillus tequilensis GXL-2p on the LB solid medium. Pick a single colony from the plate and transfer it to LB liquid medium. Place the medium in a constant temperature shaker and incubate overnight at 37 ℃ and 180 rmp until the bacterial solution becomes turbid. This allows Bacillus equilensis GXL-2p to be propagated in LB liquid medium. The turbid bacterial suspension (OD600≈1.0) was centrifuged at 5000 rpm at 4 ℃ for 10 min, the supernatant was discarded, a certain volume of culture medium was added to resuspend the bacterial suspension, and the bacterial suspension was diluted to OD600=1.0.

[0026] 3. Bacillus tequilensis GXL-2p antagonistic pathogen experiment After soaking sterilized filter paper discs in a suspension of Bacillus tequilensis GXL-2p, they were spread evenly on a plate coated with a specific crop pathogen and incubated in a 28°C incubator for 2 days. The presence of an inhibition zone around the filter paper discs was then observed. The results are attached. Figure 5 As shown, Bacillus tequilensis GXL-2p can significantly inhibit the growth and reproduction of at least eight common pathogens causing root rot and leaf spot diseases, including Alternaria solanacea, Pseudomonas pilosa, Fusarium moniliforme, Rhizoctonia solani, Fusarium oxysporum, Botrytis cinerea, Aspergillus flavus, and Phytophthora capsici.

[0027] 4. Preparation of 1 / 2 MS solid culture medium Dissolve 2.2 g MS medium (containing vitamins) powder and 8.0 g plant gel in 1 L sterile deionized water, adjust the pH to 5.8, autoclave at 121 ℃ for 15 min, and dispense into 13 cm square petri dishes in a laminar flow hood.

[0028] 5. Preparation of Kimura B nutrient solution Dissolve 254 mg of Kimura B rice nutrient solution powder and 0.2 ml of the matching 5,000× calcium concentrate in 1 L of sterile deionized water, adjust the pH to 5.8, and autoclave at 121 ℃ for 15 min.

[0029] 6. Seedling cultivation of rice (9311), maize (Zhengdan 958), and wheat (Jimai 22). Select plump rice, corn, and wheat seeds, discard shriveled seeds, and place them in sterile Erlenmeyer flasks; Add 75% alcohol until the seeds are completely submerged, sterilize for 30 seconds, and shake the bottle continuously during this time to ensure that each seed is fully in contact with the alcohol. Discard the alcohol. Add a sodium hypochlorite solution with an effective chlorine concentration of 2.5%, ensuring the solution covers the seeds, and sterilize for 15 minutes, shaking the bottle continuously during this time. Discard the sodium hypochlorite. Repeat this step 3 times. Add sterile deionized water until the seeds are submerged, and wash for 10 minutes, shaking the bottle continuously during the process. Discard the sterile water and repeat this step 3 times. Using sterile forceps, neatly and evenly spread the seeds on the surface of 1 / 2 MS solid culture medium. Each dish can hold 10 seeds. Arrange the seeds horizontally and evenly about 5 cm above the bottom of the plate, with the seed embryos facing upwards. Seal the plate with Parafilm sealing film. Place the petri dishes vertically and incubate them for 7-9 days in a culture room with 25 ℃, 16 h light, and 21% humidity; Sterile and uniformly growing rice seedlings were removed from the petri dish, and the residual culture medium on the roots was washed away with sterile water. They were then transplanted into sterile Kimura B nutrient solution. Rice seedlings were transplanted into sterile culture solution when they reached the two-leaf stage. Corn and wheat seedlings were directly transplanted into nutrient soil (nutrient substrate: vermiculite: perlite = 3:3:4).

[0030] 7. Experiment on Bacillus tequilensis GXL-2p in alleviating salt stress in rice Rice plants were divided into four groups based on a salt stress concentration of 100 mM NaCl: Group 1: Transplant rice seedlings at the two-leaf stage into Kimura B nutrient solution; Group 2: Two-leaf stage rice seedlings were transplanted into a Kimura B nutrient solution containing Bacillus tequilensis GXL-2p bacterial suspension and Kimura B nutrient solution diluted at a volume ratio of 1:9. Group 3: Transplant the two-leaf stage rice seedlings into a sterile Kimura B nutrient solution containing 100 mM NaCl; Group 4: Rice seedlings at the two-leaf stage were transplanted into Kimura B nutrient solution, which contained both Bacillus tequilensis GXL-2p bacterial suspension and 100 mM NaCl diluted in a 1:9 volume ratio with Kimura B nutrient solution. Each bottle contains 5 rice seedlings, and each treatment is replicated in 8 bottles. The rice seedlings are placed in a light incubator and the corresponding nutrient solution is added every three days or so. Data is collected on the 12th day after treatment. The results are attached. Figure 6 As shown, A represents salt-free stress and no bacterial growth; B represents salt-free stress and Bacillus tequilensis GXL-2p; C represents 100 mM NaCl stress treatment and no bacterial growth; and D represents 100 mM NaCl stress treatment and Bacillus tequilensis GXL-2p. The results are attached. Figure 7As shown in the figure, A represents the statistics of rice plant height, B represents the statistics of rice root length, C and D represent the statistics of fresh weight and dry weight of rice aboveground parts, and E and F represent the statistics of fresh weight and dry weight of rice roots, respectively; dark columns represent 0 mM NaCl treatment, and light columns represent 100 mM NaCl treatment; "*" indicates a significant difference at the p≤0.05 level, "**" indicates a significant difference at the p≤0.01 level, and "***" indicates a significant difference at the p≤0.001 level. From the appendix Figure 6 and 7 It was found that under salt-free stress conditions, the growth of rice was not significantly affected 12 days after inoculation with Bacillus tequilensis GXL-2p. However, under 100 mM NaCl stress for 12 days, the rice leaves almost completely withered and wrinkled, and white salt frost was visible at the leaf tips. In contrast, rice inoculated with Bacillus tequilensis GXL-2p significantly alleviated the damage caused by salt stress, with wilting mainly concentrated at the leaf tips. At the same time, the aboveground fresh weight, aboveground dry weight, root fresh weight, and root dry weight of rice inoculated with Bacillus tequilensis GXL-2p were all significantly higher than those of the control group (p<0.05), with increases of 23.71%, 17.62%, 12.87%, and 17.43%, respectively.

[0031] 8. Experiment on Bacillus tequilensis GXL-2p in alleviating salt stress in maize Corn was divided into the following six groups based on the salt stress concentration of 0.8% NaCl in moderately to severely saline soil: Group 1: Transfer the corn to nutrient soil; Group 2: The corn was transferred to sterile, moderately to severely saline soil containing 0.8% NaCl; Group 3: Move the corn to the area where 1×10 is added. 6 CFU / g concentration of Bacillus stequilensis GXL-2p bacterial suspension in moderately to heavily saline soil containing 0.8% NaCl; Group 4: Move the corn to the area where 1×10 7 CFU / g concentration of Bacillus stequilensis GXL-2p bacterial suspension in moderately to heavily saline soil containing 0.8% NaCl; Group 5: Move the corn to the area where 1×10 8CFU / g concentration of Bacillus stequilensis GXL-2p bacterial suspension in moderately to heavily saline soil containing 0.8% NaCl; Group 6: Move the corn to the area where 1×10 9 CFU / g concentration of Bacillus stequilensis GXL-2p bacterial suspension in moderately to heavily saline soil containing 0.8% NaCl; Each treatment was repeated in 3 pots, with 3 plants per pot. The corn was placed in a light incubator and the corresponding nutrient solution was added every three days or so. Data was collected on the 12th day after treatment. The results are attached. Figure 8 As shown, CK is a suspension of Bacillus tequilensis GXL-2p without salt or Bacillus tequilensis GXL-2p; CK0 is a suspension of Bacillus tequilensis GXL-2p with salt but without salt; B6 is a suspension of Bacillus tequilensis with salt but with 1×10⁻⁶ added. 6 Bacillus equilensis GXL-2p bacterial suspension at CFU / g; B7 is salted but with 1×10⁻⁶ added. 7 Bacillus tequilensis GXL-2p bacterial suspension at CFU / g; B8 is salted but with 1×10⁻⁶ added. 8 Bacillus tequilensis GXL-2p bacterial suspension at CFU / g; B9 is salted but with 1×10⁻⁶ added. 9 CFU / g of Bacillus tequilensis GXL-2p bacterial suspension; The results are attached. Figure 9 As shown, CK is a suspension of Bacillus tequilensis GXL-2p without salt or Bacillus tequilensis GXL-2p; CK0 is a suspension of Bacillus tequilensis GXL-2p with salt but without salt; B6 is a suspension of Bacillus tequilensis with salt but with 1×10⁻⁶ added. 6 Bacillus equilensis GXL-2p bacterial suspension at CFU / g; B7 is salted but with 1×10⁻⁶ added. 7 Bacillus tequilensis GXL-2p bacterial suspension at CFU / g; B8 is salted but with 1×10⁻⁶ added. 8Bacillus tequilensis GXL-2p bacterial suspension at CFU / g; B9 is salted but with 1×10⁻⁶ added. 9 CFU / g of Bacillus tequilensis GXL-2p bacterial suspension; "*" indicates a significant difference at the p≤0.05 level, "**" indicates a significant difference at the p≤0.01 level, and "***" indicates a significant difference at the p≤0.001 level; From the appendix Figure 8 and 9 It was found that maize seedlings under 0.8% NaCl stress for 12 days showed significant differences between different treatments. Plants without salt or Bacillus tequilensis GXL-2p suspension grew well; plants with salt but without Bacillus tequilensis GXL-2p suspension showed wilting and shriveling, especially at the leaf tips. In contrast, inoculation with different concentrations of Bacillus tequilensis GXL-2p suspension significantly alleviated the effects of salt stress on maize, and the alleviating effect increased with increasing Bacillus tequilensis GXL-2p suspension concentration. Specifically, the effect was most pronounced at a concentration of 1×10⁻⁶. 8 The most significant relief effect was observed at CFU / g; the fresh weight of plants inoculated with Bacillus tequilensis GXL-2p suspension was significantly increased compared with that of plants not inoculated with Bacillus tequilensis GXL-2p suspension (p<0.05), with increases of 19.61%, 32.42%, 39.37%, and 35.67%, respectively.

[0032] 9. Experiment on Bacillus tequilensis GXL-2p in alleviating wheat salt stress Wheat was divided into the following six groups based on the salt stress concentration of 0.8% NaCl in moderately to severely saline soil: Group 1: Transfer the wheat to nutrient soil; Group 2: Wheat was transferred to sterile, moderately to severely saline soil containing 0.8% NaCl; Group 3: Move wheat to add 1×10 6 CFU / g concentration of Bacillus stequilensis GXL-2p bacterial suspension in moderately to heavily saline soil containing 0.8% NaCl; Group 4: Move the wheat to the area where 1×10⁻⁶ mol / L wheat is added. 7 CFU / g concentration of Bacillus stequilensis GXL-2p bacterial suspension in moderately to heavily saline soil containing 0.8% NaCl; Group 5: Move the wheat to the area where 1×10⁻⁶ ppm is added. 8 CFU / g concentration of Bacillus stequilensis GXL-2p bacterial suspension in moderately to heavily saline soil containing 0.8% NaCl; Group 6: Move the wheat to the area where 1×10⁻⁶ ppm is added. 9 CFU / g concentration of Bacillus stequilensis GXL-2p bacterial suspension in moderately to heavily saline soil containing 0.8% NaCl; Each treatment was repeated in 3 pots, with 5 plants per pot. The wheat was placed in a light incubator and the corresponding nutrient solution was added every three days or so. Data was collected on the 10th day after treatment. The results are attached. Figure 10 As shown, CK is a suspension of Bacillus tequilensis GXL-2p without salt or Bacillus tequilensis GXL-2p; CK0 is a suspension of Bacillus tequilensis GXL-2p with salt but without salt; B6 is a suspension of Bacillus tequilensis with salt but with 1×10⁻⁶ added. 6 Bacillus equilensis GXL-2p bacterial suspension at CFU / g; B7 is salted but with 1×10⁻⁶ added. 7 Bacillus tequilensis GXL-2p bacterial suspension at CFU / g; B8 is salted but with 1×10⁻⁶ added. 8 Bacillus tequilensis GXL-2p bacterial suspension at CFU / g; B9 is salted but with 1×10⁻⁶ added. 9 CFU / g of Bacillus tequilensis GXL-2p bacterial suspension; The results are attached. Figure 11 As shown, CK is a suspension of Bacillus tequilensis GXL-2p without salt or Bacillus tequilensis GXL-2p; CK0 is a suspension of Bacillus tequilensis GXL-2p with salt but without salt; B6 is a suspension of Bacillus tequilensis with salt but with 1×10⁻⁶ added. 6Bacillus equilensis GXL-2p bacterial suspension at CFU / g; B7 is salted but with 1×10⁻⁶ added. 7 Bacillus tequilensis GXL-2p bacterial suspension at CFU / g; B8 is salted but with 1×10⁻⁶ added. 8 Bacillus tequilensis GXL-2p bacterial suspension at CFU / g; B9 is salted but with 1×10⁻⁶ added. 9 CFU / g of Bacillus tequilensis GXL-2p bacterial suspension; "*" indicates significant difference at the p≤0.05 level; From the appendix Figure 10 and 11 The results showed that wheat seedlings under 0.8% NaCl stress for 10 days exhibited significant differences between treatments. Plants without salt or Bacillus tequilensis GXL-2p suspension showed good growth. Plants with salt but without Bacillus tequilensis GXL-2p suspension were significantly shorter, but did not show severe wilting or leaf drop, indicating that wheat itself has some resistance to salt stress; however, this salt concentration still significantly inhibited its growth. In contrast, inoculation with different concentrations of Bacillus tequilensis GXL-2p suspension significantly alleviated the effects of salt stress on wheat, but the alleviating effect did not differ significantly with increasing inoculation amount. The fresh weight of plants inoculated with Bacillus tequilensis GXL-2p suspension was significantly lower than that of plants not inoculated with Bacillus tequilensis GXL-2p suspension. The fresh weight of plants treated with GXL-2p bacterial suspension of tequilensis was significantly increased (p<0.05), with increases of 31.61%, 32.42%, 35.37%, and 36.17%, respectively.

[0033] In summary, Bacillus tequilensis GXL-2p significantly inhibits the growth and reproduction of at least eight common pathogens causing root rot and leaf spot diseases in crops, including Alternaria alternata, Pseudomonas stolonifera, Fusarium moniliforme, Rhizoctonia solani, Fusarium oxysporum, Botrytis cinerea, Aspergillus flavus, and Phytophthora capsici. Simultaneously, it assists plants in resisting salt stress and significantly increases plant biomass under stress conditions. Thus, it possesses both biocontrol and growth-promoting functions. On the one hand, it can serve as a biocontrol agent for controlling various diseases such as root rot and leaf spot; on the other hand, it is an important plant probiotic that assists crops in resisting stress. It is particularly effective in enhancing the resistance of field crops such as rice, corn, and wheat under salt stress, thus helping to improve the planting efficiency of these crops in saline-alkali land.

[0034] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A type of Bacillus tergentii, characterized in that, The Bacillus tequilensis mentioned is Bacillus tequilensis GXL-2p, which was deposited at the China Center for Type Culture Collection, Wuhan University on October 28, 2025, with accession number CCTCC NO: M 20252363.

2. The *Bacillus tekirii* strain according to claim 1, characterized in that: The 16S rDNA sequence of Bacillus tequilensis GXL-2p is shown in SEQ ID NO.

3.

3. The application of Bacillus tekirii as described in claim 1 in the control of crop root rot and leaf spot diseases.

4. The application according to claim 3, characterized in that: The pathogens causing the root rot and leaf spot diseases of the crops are one or more of the following: Alternaria solanacea, Pseudomonas stolonifera, Fusarium moniliforme, Rhizoctonia solani, Fusarium oxysporum, Botrytis cinerea, Aspergillus flavus, and Phytophthora capsici.

5. An application of Bacillus tekiria as described in claim 1 in assisting crop stress resistance.

6. The application according to claim 5, characterized in that: The crop is one or more of rice, corn, and wheat.

7. The application according to claim 6, characterized in that: The resistance mentioned is salt stress resistance.

8. The application according to claim 7, characterized in that: The method of assisting crops in resisting stress is to add a suspension of Bacillus tequilensis GXL-2p.

9. The application according to claim 8, characterized in that: The preparation steps of the Bacillus equilensis GXL-2p bacterial suspension include: Using a sterile pipette tip, aspirate 100-200 μL of Bacillus tequilensis GXL-2p from a glycerol tube and transfer it onto LB solid medium. Spread the medium using the continuous streak method and incubate at 30 °C for 1-2 days to activate Bacillus tequilensis GXL-2p on the LB solid medium. Pick a single colony from the plate and transfer it to LB liquid medium. Place the medium in a constant temperature shaker and incubate overnight at 37 ℃ and 180 rpm until the bacterial solution becomes turbid, so that Bacillus equilensis GXL-2p can be propagated in LB liquid medium. The turbid bacterial suspension with OD600≈1.0 was centrifuged at 5000 rpm at 4 ℃ for 10 min, the supernatant was discarded, the bacterial suspension was resuspended in culture medium, and the bacterial suspension was diluted to OD600=1.

0.

10. The application according to claim 9, characterized in that: The preparation steps of the LB medium include: 5.0 g / L tryptone, 3.0 g / L yeast, 0.87 g / L calcium chloride, distilled water to a final volume of 1 L, autoclaved at 121 °C for 20 min; For solid culture media, 15.0 g / L of agar powder is added.

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