Bacillus subtilis JTCS-01 and application thereof

Abstract

The invention provides bacillus subtilis JTCS-01 and application thereof, and belongs to the field of microorganisms. The preservation number of the bacillus subtilis JTCS-01 is CGMCC (China General Microbiological Culture Collection Center) NO.37197, the preservation address of the bacillus subtilis JTCS-01 is China General Microbiological Culture Collection Center, and the preservation time of the bacillus subtilis JTCS-01 is December 25, 2025. The strain disclosed by the invention can efficiently secrete plant growth regulators such as indoleacetic acid and cytokinin at the same time and generate antibacterial substances such as lipopeptide antibiotics, so that multiple functions of promoting plant growth, preventing and treating fungal diseases and improving a soil micro-ecological environment are integrated, and a powder or liquid fungicide developed on the basis of the strain has a good application prospect. The fertilizer can be applied to seed treatment, root irrigation and soil application.

Description

Technical Field

[0001] This application relates to the field of microbial technology, and in particular to a Bacillus subtilis JTCS-01 and its applications. Background Technology

[0002] Bacillus subtilis, a common plant rhizosphere growth-promoting bacterium, has attracted widespread attention in the field of agricultural microbiology due to its ability to form highly resistant spores. Currently, related research and applications largely focus on utilizing its single or partial functions. For example, some strains emphasize promoting plant growth by producing substances such as indoleacetic acid, while others primarily rely on secreting antimicrobial substances to control specific diseases. However, in actual agricultural production, healthy crop growth often requires addressing multiple challenges simultaneously, including slow growth, disease invasion, and soil degradation.

[0003] Existing technical solutions typically employ a combination of multiple single-function microbial agents or chemical fertilizers and pesticides. This not only increases application costs and operational complexity but may also lead to unstable efficacy, antagonistic interactions between microbial strains, and potential environmental risks. Therefore, obtaining a Bacillus subtilis strain that can simultaneously and efficiently promote plant growth, control plant diseases, and improve the soil microecological environment, and developing stable and efficient products, has become an urgent technical problem to be solved. Summary of the Invention

[0004] This application provides a Bacillus subtilis JTCS-01 and its application, which solves the following technical problem: how to simultaneously promote plant growth, prevent and control plant diseases and improve the soil micro-ecological environment.

[0005] In the first aspect, this application provides a Bacillus subtilis JTCS-01, which has the accession number CGMCC NO.37197, is deposited at the China General Microbiological Culture Collection Center, and was deposited on December 25, 2025.

[0006] Optionally, the 16S rDNA sequence of Bacillus subtilis JTCS-01 is shown in SEQ ID No. 1.

[0007] Optionally, the Bacillus subtilis JTCS-01 may produce indoleacetic acid and cytokinin.

[0008] Optionally, the Bacillus subtilis JTCS-01 can produce lipopeptide antibiotics and antimicrobial proteins to inhibit plant pathogenic fungi.

[0009] Secondly, embodiments of this application provide a microbial agent, which includes Bacillus subtilis JTCS-01, fermentation product of Bacillus subtilis JTCS-01, or culture of Bacillus subtilis JTCS-01 as described in the first aspect.

[0010] Optionally, the microbial agent may be in the form of a powder or a liquid.

[0011] Thirdly, embodiments of this application provide the application of Bacillus subtilis JTCS-01 as described in the first aspect in promoting plant growth.

[0012] Fourthly, embodiments of this application provide the application of Bacillus subtilis JTCS-01 as described in the first aspect in the prevention and control of plant diseases.

[0013] Fifthly, embodiments of this application provide the application of Bacillus subtilis JTCS-01 as described in the first aspect in improving soil environments.

[0014] The technical solutions provided in this application have the following advantages compared with the prior art:

[0015] (1) Promote plant growth: Bacillus subtilis JTCS-01 can produce a large amount of plant growth regulators such as indoleacetic acid and cytokinin after fermentation. After application, it can effectively stimulate the rapid division and growth of plant cells, promote crop growth, help crops to take root, improve the lodging resistance of crops, and increase crop yield.

[0016] (2) Prevention and control of plant diseases: Bacillus subtilis JTCS-01 can produce active substances such as lipopeptide antibiotics and antibacterial proteins, which cause the fungal hyphae that cause crop fungal diseases to break, twist, swell and deform, effectively inhibiting crop fungal diseases and can effectively prevent soil-borne diseases such as root rot, stem rot, stem base rot, damping-off, Verticillium wilt, and take-all disease.

[0017] (3) Improved soil microecological environment: After applying Bacillus subtilis JTCS-01 to the soil, the number of pathogenic fungi causing plant diseases decreased significantly, while the number of beneficial bacteria increased significantly, effectively changing the soil rhizosphere microbial community environment and making the soil healthier. Furthermore, after applying Bacillus subtilis JTCS-01, the activities of major soil enzymes such as protease, phosphatase, and amylase were significantly enhanced, while the activity of urease decreased, resulting in a significant improvement in soil vitality. This effectively increases fertilizer utilization, improves the efficiency of plant fertilizer absorption, increases crop yield, and improves crop quality. In addition, Bacillus subtilis JTCS-01 can effectively colonize the soil, occupy ecological niches, compress the living space of fungal diseases, reduce the number of pathogenic fungi in the soil, and alleviate or eliminate continuous cropping obstacles. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a morphological diagram of the plate culture of Bacillus subtilis JTCS-01 provided in the embodiments of this application;

[0021] Figure 2 This is a diagram illustrating the growth-promoting effect of JTCS-01 on corn seedlings, provided in Example 4 of this application.

[0022] Figure 3 This is a diagram illustrating the growth-promoting effect of JTCS-01 on wheat seedlings, provided in Example 4 of this application.

[0023] Figure 4 This is a diagram illustrating the effect of JTCS-01 on the root growth of cucumber seedlings, provided in Example 4 of this application.

[0024] Figure 5 The image shows the inhibitory and hyphal disruption effects of JTCS-01 on pathogenic fungi, as provided in Example 5 of this application. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0026] This application provides a Bacillus subtilis JTCS-01, which has the accession number CGMCC NO.37197, is deposited at the China General Microbiological Culture Collection Center, and was deposited on December 25, 2025.

[0027] In some embodiments, the 16S rDNA sequence of the Bacillus subtilis JTCS-01 is shown in SEQ ID No. 1.

[0028] In some embodiments, the Bacillus subtilis JTCS-01 can produce indoleacetic acid and cytokinin.

[0029] In some embodiments, the Bacillus subtilis JTCS-01 can produce lipopeptide antibiotics and antimicrobial proteins to inhibit plant pathogenic fungi.

[0030] Based on a general inventive concept, this application provides a microbial agent comprising Bacillus subtilis JTCS-01, fermentation product of Bacillus subtilis JTCS-01, or culture of Bacillus subtilis JTCS-01 as described above.

[0031] In some embodiments, the microbial agent is in the form of a powder or a liquid.

[0032] Bacillus subtilis strains can produce spores and are highly resistant to adverse conditions, making them one of the most commonly used and important microbial species in agriculture. This application describes the *Bacillus subtilis* strain JTCS-01, a high-yielding plant growth-promoting rhizobacteria (PGPR) strain screened from soils surrounding the Longwangshan Nature Reserve in Anji County. This strain exhibits strong inhibitory effects against plant pathogens, effectively controlling fungal diseases and increasing crop yield.

[0033] After years of research, the research team has continuously improved and innovated the strain, optimized the fermentation process, increased the content of fermentation products, and stabilized the filling process. Currently, the JTCS-01 strain exhibits high liquid fermentation levels, high spore formation rates, high growth regulator yields, product stability, and long shelf life. Multiple product forms, including powder and liquid formulations, have been developed, and the products have received unanimous praise from growers for their effectiveness.

[0034] Based on a general inventive concept, embodiments of this application provide an application of Bacillus subtilis JTCS-01 as described above in promoting plant growth.

[0035] After fermentation, Bacillus subtilis JTCS-01 can produce a large amount of plant growth regulators such as indoleacetic acid and cytokinins. After application, it can effectively stimulate the rapid division and growth of plant cells, promote crop growth, help crops to take root, improve the lodging resistance of crops, and increase crop yield.

[0036] Based on a general inventive concept, embodiments of this application provide an application of Bacillus subtilis JTCS-01 as described above in the prevention and control of plant diseases.

[0037] Bacillus subtilis JTCS-01 can produce active substances such as lipopeptide antibiotics and antibacterial proteins, which cause the mycelia of fungi that cause fungal diseases in crops to break, twist, swell and deform, thus effectively inhibiting fungal diseases in crops and can effectively prevent soil-borne diseases such as root rot, stem rot, stem base rot, damping-off, Verticillium wilt and take-all disease.

[0038] Based on a general inventive concept, embodiments of this application provide an application of Bacillus subtilis JTCS-01 as described above in improving soil environments.

[0039] After applying Bacillus subtilis JTCS-01 to the soil, the number of pathogenic fungi causing plant diseases significantly decreased, while the number of beneficial bacteria significantly increased, effectively altering the soil rhizosphere microbial environment and making the soil healthier. Furthermore, after applying Bacillus subtilis JTCS-01, the activities of major soil enzymes such as protease, phosphatase, and amylase significantly increased, while the activity of urease decreased, resulting in significantly improved soil vitality. This effectively increases fertilizer utilization, improves the efficiency of plant fertilizer absorption, increases crop yield, and improves crop quality. In addition, Bacillus subtilis JTCS-01 can effectively colonize the soil, occupy ecological niches, compress the living space of fungal diseases, reduce the number of pathogenic fungi in the soil, and alleviate or eliminate continuous cropping obstacles.

[0040] In summary, the Bacillus subtilis JTCS-01 strain and its application involved in this patent application demonstrate significant advantages on multiple levels.

[0041] From the perspective of strain origin and function, this invention possesses the advantages of original innovation and functional synergy. The JTCS-01 strain was screened from soils surrounding a nature reserve with special ecological value, and its genetic background may contain unique metabolic potential. More importantly, this strain successfully integrates three core functions: growth promotion, disease resistance, and soil improvement. It can efficiently secrete indoleacetic acid and cytokinins to directly promote crop growth; simultaneously, it produces lipopeptide antibiotics and other substances to effectively inhibit various pathogenic fungi; and it can improve soil health through rhizosphere colonization, optimization of the microbial community, and regulation of soil enzyme activity. This multifunctionality enables it to systematically address complex agricultural production problems, exhibiting higher comprehensive benefits and field stability than single-function microbial agents.

[0042] From a technological research and development and industrialization perspective, this invention demonstrates excellent technological maturity and process controllability. Through long-term strain selection and fermentation process optimization, JTCS-01 has acquired superior industrialization characteristics, exhibiting high-density fermentation levels, high spore formation rates, and high and stable production of growth regulators. The final product, existing in spore form, endows it with excellent stress resistance and a long shelf life. Currently, based on this strain, various stable products, including powder and liquid formulations, have been successfully developed, forming a complete production process and providing reliable technical support for large-scale market application.

[0043] The present application is further illustrated below with reference to specific embodiments. Experimental methods in the following embodiments that do not specify specific conditions are generally determined according to national standards / industry standards / the disclosure herein; if there are no corresponding national standards / industry standards / the disclosure herein, they are performed according to generally accepted international standards, conventional conditions, or conditions recommended by the manufacturer.

[0044] Example 1: Isolation, screening and identification of Bacillus subtilis JTCS-01

[0045] Sample source and isolation: Samples were collected from the rhizosphere soil of healthy vegetation surrounding the Longwangshan Nature Reserve in Anji County, Zhejiang Province. Isolation was performed on LB agar plates using the dilution spread method and incubated at 35-37℃ for 24-48 hours.

[0046] Functional screening: Single colonies with different morphologies were selected and inoculated onto a medium containing L-tryptophan. The Salkowski colorimetric method was used to screen strains with strong indoleacetic acid (IAA) production ability. At the same time, the plate confrontation method was used to test their inhibitory ability against common pathogenic fungi (such as Fusarium and Rhizoctonia).

[0047] Secondary screening and identification of strains: Strains exhibiting both high IAA production and strong antagonistic function were selected from the initial screening strains for secondary screening via liquid fermentation. IAA and cytokinin production and antimicrobial activity were quantitatively determined. Finally, the strain with the best performance was identified and named JTCS-01.

[0048] Strain identification: The 16S rDNA sequence of JTCS-01 was determined (sequence shown in SEQ ID NO: 1, >2930-XM-25-0343-LB8-32_TSS20251217-0571-08708-BSND). The 16S rDNA sequence length of Bacillus subtilis strain JTCS-01 was 1467 bp. Homology was compared with all previously determined 16S rDNA sequences of prokaryotes in GenBank. Bacillus subtilis JTCS-01 showed 99.93% similarity to NR113265 Bacillus subtilis. Their cell morphology (e.g., ...) was also similar. Figure 1 The image shown matches the characteristics of Bacillus subtilis and can be identified as Bacillus subtilis.

[0049] This strain was deposited at the China General Microbiological Culture Collection Center on December 25, 2025, with accession number CGMCC NO. 37197.

[0050] Example 2: Fermentation culture of Bacillus subtilis JTCS-01

[0051] Liquid fermentation medium formulation (1L): 10 g tryptone, 5 g yeast extract, 10 g sodium chloride, pH 7.2 (no agar added to the liquid medium). Inoculate a single colony of JTCS-01 into this medium and incubate at 35-37℃ with shaking at 200 rpm for approximately 24 hours to reach the late logarithmic growth stage, at which point the cell concentration and spore formation rate are high.

[0052] Example 3: Preparation of Bacillus subtilis JTCS-01 inoculum

[0053] The fermentation broth obtained in Example 2 was then post-treated:

[0054] Liquid inoculum: Fermentation broth tested (live count ≥ 2×10⁻⁶) 9 After obtaining the concentration of CFU / mL, stabilizers, additives, etc. can be added directly for filling.

[0055] Powdered microbial inoculum: The fermentation broth is centrifuged to collect the microbial cells, which are then mixed with a carrier (such as diatomaceous earth, wheat bran, humic acid, etc.) and spray-dried or dried at low temperature to produce a powder, ensuring that the effective viable count in the finished product is ≥ 2×10⁻⁶. 10 CFU / g.

[0056] Example 4

[0057] Example 4: Verification of the growth-promoting effect of JTCS-01 based on plant growth regulators

[0058] This embodiment aims to directly quantify the content of rhizosphere plant growth regulators and analyze their correlation with growth-promoting phenotypes, mechanistically demonstrating that Bacillus subtilis JTCS-01 promotes plant growth by secreting substances such as indoleacetic acid (IAA) and cytokinin (CTK). The experimental results are shown in Table 1.

[0059] 1. Preparation and optimization of microbial inoculants (aiming to maximize the yield of plant growth regulators)

[0060] To obtain inoculum material for high-yield plant growth regulators, the fermentation process of JTCS-01 was optimized as follows:

[0061] Fermentation medium optimization: An optimized growth-promoting metabolic medium (GMPM) was used, with the following formulation: tryptone 5 g / L, yeast extract 3 g / L, L-tryptophan 1 g / L, adenine sulfate 0.05 g / L, glucose 10 g / L, pH 7.0. L-tryptophan is a precursor for IAA synthesis, and adenine sulfate promotes CTK synthesis.

[0062] Fermentation process: JTCS-01 seed culture was inoculated into GMPM medium at a 2% inoculum and fermented at 35℃ and 200 rpm for 60 hours with shaking. The fermentation endpoint time, determined by previous experiments, was the common peak period of IAA and CTK yields, rather than the single maximum biomass period.

[0063] Inoculum preparation: After fermentation, the fermentation broth is used directly as the whole fermentation broth containing metabolites without centrifugation. After determining its basic IAA and CTK content, it is diluted with sterile water to the application concentration.

[0064] 2. Application Methods and Experimental Design

[0065] The tested crops were: corn, wheat, and cucumber.

[0066] Experimental treatment:

[0067] T (JTCS-01 treatment group): Use the above-mentioned diluted JTCS-01 whole fermentation broth (viable count 1×10⁻⁶). 8 The root irrigation was performed using CFU / mL. Each seedling (three-leaf stage) was irrigated with 50 mL, and the treatment was repeated on days 3, 7, and 14 after the initial treatment.

[0068] CK (blank control group): roots were drenched with an equal volume of sterile fermentation medium (without bacteria) of the same pH value.

[0069] Experimental setup: A pot experiment was conducted, with 10 replicates per treatment, arranged in a completely randomized block design. Samples were collected and measured on day 7 after the last treatment (i.e., the end of the seedling period).

[0070] 3. Measurement Indicators and Methods

[0071] Preparation of rhizosphere soil extract: Carefully shake off the loose soil from the plant roots and collect the tightly attached rhizosphere soil. Weigh 5.0 g of fresh rhizosphere soil, add 10 mL of pre-cooled 80% methanol extract, and extract by ultrasonication in an ice bath for 30 minutes. Centrifuge at 4℃ and 10,000 rpm for 15 minutes, collect the supernatant, dry it under nitrogen, redissolve it in 1 mL of methanol, filter it through a 0.22 μm filter membrane, and prepare for analysis.

[0072] IAA content determination: Absolute quantification was performed using high-performance liquid chromatography-mass spectrometry (HPLC-MS / MS). Chromatographic column: C18 column; mobile phase: 0.1% formic acid-acetonitrile; multiple reaction monitoring mode. External standard method was used for quantification.

[0073] CTK content determination: Four major cytokinins, namely zeatin (Z), zeatin nucleoside (ZR), isopentenyl adenine (iP), and isopentenyl adenine (iPA), were simultaneously determined by HPLC-MS / MS. The method was the same as that for IAA determination.

[0074] Table 1. Effects of JTCS-01 treatment on rhizosphere plant growth regulator content and growth in crops.

[0075]

[0076] From Table 1 and Figures 2-4 This embodiment demonstrates the core mechanism and main effects of Bacillus subtilis JTCS-01 treatment: it significantly increases the content of indoleacetic acid (IAA) and cytokinin (CTK) in the rhizosphere soil of maize, wheat, and cucumber, with increases exceeding 2.5 times. This mechanism translates into a coordinated growth-promoting effect in maize and wheat, manifested as a significant increase of 30%–60% in plant height, total root length, and aboveground biomass, with the most prominent effect on root development, which highly aligns with the classic functions of plant growth regulators.

[0077] However, the response data for cucumber exhibited a significant peculiarity, differing from the patterns observed in maize and wheat. Although the JTCS-01 treatment also significantly increased the rhizosphere IAA and CTK contents in cucumber (by 2.8 and 2.6 times, respectively), its growth-promoting effect showed a strong "bias": the root growth response was extremely vigorous, with a total root length increase of up to 98.4%. Cucumber may be more sensitive to the surge in IAA / CTK in the rhizosphere, and its signal transduction or resource allocation mechanism may have led to an extremely preferential allocation of photosynthetic products and energy to the construction and expansion of the underground root system during the experimental period, temporarily inhibiting the elongation growth of the aboveground parts.

[0078] Example 5: Inhibitory effect of Bacillus subtilis JTCS-01 on pathogenic fungi

[0079] This embodiment aims to verify the inhibitory effect of Bacillus subtilis JTCS-01 on various plant pathogenic fungi and to observe its destructive effect on the hyphal morphology of pathogenic fungi.

[0080] 1. Test strains and culture

[0081] Biocontrol bacteria: Bacillus subtilis JTCS-01, activated and prepared at a concentration of 1×10⁻⁶ according to the method in Example 2. 8Fresh bacterial suspension at CFU / mL.

[0082] Pathogenic fungi: Three important plant pathogenic fungi were selected as targets: Fusarium oxysporum (causing wilt), Rhizoctonia solani (causing damping-off), and Botrytis cinerea (causing gray mold). The pathogenic fungi were activated and cultured on PDA (potato dextrose agar) plates at 28°C for later use.

[0083] 2. Flat Plate Standoff Test

[0084] The antibacterial activity of JTCS-01 was evaluated using the plate confrontation method. A 5 mm diameter fungal disc was inoculated into the center of a PDA plate. Two μL of fresh JTCS-01 bacterial suspension (or sterile LB medium as a blank control) was then inoculated at equal intervals 2.5 cm from the fungal disc. Each treatment was performed in triplicate. The plates were incubated at 28°C. Data were measured and recorded when the fungal colonies in the blank control group had completely covered the plates (approximately 5-7 days).

[0085] 3. Antibacterial activity assay

[0086] After the confrontation culture was completed, JTCS-01 showed significant inhibitory effects on all three pathogenic fungi (Table 2).

[0087] Table 2. Inhibitory effect of JTCS-01 on three plant pathogenic fungi in plate confrontation.

[0088]

[0089] As shown in Table 2, JTCS-01 has an inhibition rate of over 65% against all three pathogenic fungi, with the strongest inhibitory effect against Rhizoctonia solani, reaching an inhibition rate of 76.4%.

[0090] Depend on Figure 5 It can be seen that a clear and wide inhibition zone was formed around the JTCS-01 colony, indicating that it can effectively inhibit the spread of pathogenic fungi, and JTCS-01 can cause severe morphological damage to the hyphae of pathogenic fungi.

[0091] Example 6: The effect of Bacillus subtilis JTCS-01 on improving the soil microecological environment

[0092] This embodiment aims to systematically verify the effect of applying Bacillus subtilis JTCS-01 on improving soil microbial flora, key enzyme activity and continuous cropping obstacles through pot experiments, and to clarify its application potential in cultivating healthy soil.

[0093] 1. Experimental Design

[0094] Test soil: Collect diseased soil from greenhouse cucumbers with continuous cropping obstacles (cucumbers have been planted for 3 consecutive seasons), sieve and mix well before use.

[0095] The crop tested was cucumber ('Jinchun No. 4').

[0096] Experimental treatment: There were 4 treatments, with 5 replicates for each treatment.

[0097] CK (blank control): No microbial agents or fertilizers were applied.

[0098] CF (Fertilizer Control): Application of conventional compound fertilizer (N-P2O5-K2O = 15-15-15).

[0099] CP (Commercial Inoculum Control): Application of commercially available Bacillus subtilis inoculum (live count ≥ 2 × 10⁻⁶) 9 CFU / g).

[0100] T (JTCS-01 treatment): Apply the JTCS-01 bacterial agent of the present invention (viable count ≥ 2 × 10⁻⁶). 9 CFU / g).

[0101] Application method: All microbial agents and fertilizers should be mixed with the soil during seedling cultivation. The dosage of JTCS-01 and commercial microbial agents is 2 g / kg soil. Apply conventional compound fertilizer according to local recommendations. Perform routine water management during the cucumber seedling growth period.

[0102] 2. Measurement Items and Methods

[0103] After the cucumber seedling stage ended (60 days after treatment), rhizosphere soil samples were collected from each treatment and the following measurements were performed: Soil microbial community analysis: High-throughput sequencing technology (16S rRNA gene and ITS gene sequencing) was used to analyze the community composition and diversity of soil bacteria and fungi.

[0104] Soil enzyme activity determination: Protease activity: The ninhydrin colorimetric method was used with casein as the substrate, and the results were expressed as the number of milligrams of amino acids produced per gram of soil after 24 hours.

[0105] Phosphatase activity: The results were expressed as the number of milligrams of phenol released per gram of soil after 24 hours, using the sodium phenyl phosphate colorimetric method.

[0106] Amylase activity: The 3,5-dinitrosalicylic acid colorimetric method was used, and the results were expressed as the number of milligrams of glucose produced per gram of soil after 24 hours.

[0107] Urease activity: The indophenol blue colorimetric method was used, and the results were expressed as the number of milligrams of NH3-N released per gram of soil after 24 hours.

[0108] Soil physicochemical and biological indicators: Soil pH, electrical conductivity (EC), and organic matter content were measured, and the ratio of culturable fungi to bacteria (F / B) was determined using the dilution plating method.

[0109] Plant growth response: The aboveground dry weight of cucumber plants was measured.

[0110] 3. Impact on soil microbial community

[0111] High-throughput sequencing results (Table 3) showed that, compared with CK, T treatment (JTCS-01) significantly altered the rhizosphere soil microbial community structure.

[0112] Bacterial diversity: The Chao1 and Shannon indices of the bacterial community in the T treatment were significantly higher than those in the CK and CF treatments, indicating that JTCS-01 can significantly increase the richness and diversity of soil bacteria.

[0113] Community composition: At the phylum level, the T treatment significantly increased the relative abundance of Proteobacteria (the group to which many beneficial growth-promoting bacteria belong) and Firmicutes, while decreasing the relative abundance of Acidobacteria. At the genus level, the relative abundance of Bacillus increased dramatically.

[0114] Table 3. Effects of different treatments on the rhizosphere soil microbial community and biological properties of cucumber.

[0115]

[0116] As shown in Table 3, the relative abundance of Fusarium oxysporum, the causative agent of wilt disease, decreased by 65.8% in the T treatment compared to the CK treatment, while it only decreased by 31.2% in the CP treatment (commercial inoculant). Simultaneously, the culturable fungal / bacterial ratio (F / B) in the soil was lowest in the T treatment, indicating a shift in the soil microecology from a "fungal type" to a healthier "bacterial type".

[0117] 4. Effects on the activity of key soil enzymes

[0118] Soil enzyme activity is a direct indicator of soil metabolic function. As shown in Table 4, the JTCS-01 treatment specifically regulated soil enzyme activity.

[0119] Table 4 Effects of different treatments on enzyme activity in cucumber rhizosphere soil

[0120]

[0121] As shown in Table 4, the activities of protease, phosphatase, and amylase in treatment T were significantly higher than those in all other treatments, increasing by 42.7%, 58.3%, and 36.1% respectively compared to the control (CK). This indicates that JTCS-01 can effectively enhance the decomposition of organic matter, the activation of phosphorus, and the conversion of carbon in the soil, thereby improving soil fertility and nutrient supply.

[0122] Meanwhile, compared with the CK and CF treatments, the urease activity in the T treatment was significantly reduced by 25.4%. Excessive urease activity leads to rapid hydrolysis of urea into ammonia, resulting in volatilization and loss. The moderate inhibition of urease activity by JTCS-01 helps slow down nitrogen fertilizer release, improve nitrogen utilization efficiency, and reduce losses.

[0123] The range descriptions used herein, such as numerical ranges and proportional ranges, include all possible sub-ranges and single numerical values ​​within that range. For example, the range descriptions of "1 to 6" or "1~6" cover all sub-ranges from 1 to 6 (such as 1 to 3, 2 to 5, etc.) and single numbers (such as 1, 2, 3, 4, 5, 6). Unless otherwise specified, the terms "including" and "contains" as used herein mean "including but not limited to"; relational terms such as "first" and "second" are used only to distinguish different entities or operations and do not imply an actual order or relationship; "and / or" indicates that multiple situations can exist individually or simultaneously; expressions such as "at least one," "multiple," and "at least one" refer to any combination of the corresponding objects, including combinations of single or multiple objects.

[0124] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A Bacillus subtilis JTCS-01, characterized in that, The Bacillus subtilis JTCS-01 has the accession number CGMCC NO.37197, is deposited at the China General Microbiological Culture Collection Center, and was deposited on December 25, 2025.

2. The Bacillus subtilis JTCS-01 according to claim 1, characterized in that, The 16S rDNA sequence of Bacillus subtilis JTCS-01 is shown in SEQ ID No.

1.

3. The Bacillus subtilis JTCS-01 according to claim 2, characterized in that, The Bacillus subtilis JTCS-01 can produce indoleacetic acid and cytokinin.

4. The Bacillus subtilis JTCS-01 according to claim 2, characterized in that, The Bacillus subtilis JTCS-01 can produce lipopeptide antibiotics and antimicrobial proteins to inhibit plant pathogenic fungi.

5. A microbial inoculant, characterized in that, The microbial agent includes Bacillus subtilis JTCS-01, fermentation product of Bacillus subtilis JTCS-01, or culture of Bacillus subtilis JTCS-01 as described in any one of claims 1 to 4.

6. The microbial agent according to claim 5, characterized in that, The microbial agent is in the form of powder or liquid.

7. The use of Bacillus subtilis JTCS-01 according to any one of claims 1 to 4 in promoting plant growth.

8. The application of Bacillus subtilis JTCS-01 according to any one of claims 1 to 4 in the prevention and control of plant diseases.

9. The application of Bacillus subtilis JTCS-01 according to any one of claims 1 to 4 in improving soil environments.

Images