Aeromonas sanarelli and use thereof

Abstract

The application belongs to the technical field of agricultural microorganisms, and particularly relates to a strain of Aeromonas sanarellii and application thereof; the Aeromonas sanarellii is classified as Aeromonas sanarellii, the strain number is P1-5, has been preserved in the China General Microbiological Culture Collection Center on October 31, 2024, the preservation number is CGMCC No. 32451; the 16S rDNA nucleotide sequence of the Aeromonas sanarellii is shown as SEQ ID NO. 1; the strain has the abilities of nitrogen fixation, phosphorus dissolution and growth promotion, and can grow normally under a 2% NaCl culture condition, thereby providing a new type of microbial resource for treatment of coastal saline-alkali soil; the strain can also significantly increase the absorption of nutrient elements such as nitrogen and phosphorus, enhance the salt tolerance and stress resistance of plants, and promote the growth of plants, and has a wide application prospect in aspects of saline-alkali soil improvement and plant growth promotion and stress resistance.

Description

Technical Field

[0001] This invention belongs to the field of agricultural microbial technology, specifically relating to a strain of Aeromonas saurischia and its applications. Background Technology

[0002] Coastal saline-alkali soil is one of the main types of saline-alkali soil. However, due to its high salt content and low soil fertility, coastal saline-alkali soil restricts plant growth and significantly reduces agricultural productivity. Excessive salt content in the soil disrupts the ion homeostasis within plant cells, hinders the absorption of necessary nutrients, and has toxic effects on plant roots and growth. Therefore, the rational utilization and improvement of saline-alkali land is of great significance to ensuring my country's food security.

[0003] Existing common methods for improving saline-alkali soil include irrigation and salt leaching, application of chemical amendments, and organic fertilizers. However, these methods are usually costly and may have negative environmental impacts. The use of biological methods to improve saline-alkali soil, particularly microbial remediation technology, has received widespread attention in recent years. Studies have shown that certain microbial groups, such as nitrogen-fixing bacteria, phosphate-solubilizing bacteria, and potassium-solubilizing bacteria, can effectively improve the soil environment, enhance plant tolerance to saline-alkali environments, and promote plant growth, demonstrating significant application potential in the improvement of saline-alkali soil and increased crop yields.

[0004] Currently, the microorganisms found to be suitable for saline-alkali land improvement are mainly salt-tolerant species such as Bacillus, Pseudomonas, and Halomonas. The potential of Aeromonas in saline-alkali land improvement is gradually being explored, with the salt tolerance and plant growth-promoting functions of the *Bivalvia* strain already proven. However, research on *Aeromonas sanarellii* in saline-alkali land improvement has not yet been reported. Therefore, developing *Aeromonas sanarellii* with strong salt and alkali adaptability and exploring its application in saline-alkali land improvement and agricultural production has significant scientific and practical value. Summary of the Invention

[0005] The technical problem this invention aims to solve is to address the shortcomings of existing technologies by providing a strain of Aeromonas saline-alkali bacteria, P1-5, for improving coastal saline-alkali soils and its applications. This strain exhibits strong salt tolerance and various growth-promoting properties, including nitrogen fixation, phosphorus solubilization, siderophore production, and indoleacetic acid (IAA) production. It can also significantly reduce soil salinity, increase available phosphorus content, and promote nutrient absorption by plants in coastal saline-alkali soils, thereby enhancing plant salt tolerance and stress resistance and promoting plant growth.

[0006] To address the aforementioned technical problems, this invention discloses a strain of Aeromonas sanarellii, classified and named P1-5, which was deposited on October 31, 2024, at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC No. 32451.

[0007] The 16S rDNA nucleotide sequence of Aeromonas saurischia is shown in SEQ ID NO.1.

[0008] SEQ ID NO.1:

[0009]

[0010] The aforementioned Aeromonas saurischia is a Gram-negative bacterium with smooth, rounded colonies that are light yellow and opaque.

[0011] Among them, Aeromonas sauris has the functions of nitrogen fixation and inorganic phosphorus dissolution.

[0012] Among them, Aeromonas saurischia has plant stress resistance and growth-promoting functions by secreting siderophores and producing indoleacetic acid.

[0013] Furthermore, the application of Aeromonas saline-alkali in the improvement of coastal saline-alkali soil is also within the scope of protection of this invention.

[0014] Specifically, the application refers to the use of Aeromonas sanguinis in reducing soil salinity and / or increasing available phosphorus in coastal saline-alkali soils.

[0015] Furthermore, the application of Aeromonas saline-alkali in promoting plant growth in coastal saline-alkali soils is also within the scope of protection of this invention.

[0016] Specifically, the application includes at least one of the following applications:

[0017] The application of Aeromonas saline-alkali bacteria in promoting plant growth such as biomass, vine length, and stem diameter in coastal saline-alkali soil;

[0018] The application of Aeromonas saline-alkali in promoting the absorption of nitrogen and phosphorus nutrients by plants in coastal saline-alkali soil;

[0019] The *Aeromonas sanrelii* species reduces Na+ in plants in coastal saline-alkali soils. + / K + Compared to other applications, this increases the salt tolerance and stress resistance of plants;

[0020] Preferably, the above-mentioned plants include, but are not limited to, sweet potatoes.

[0021] Furthermore, the present invention also provides a coastal saline-alkali soil conditioner, wherein the conditioner contains the aforementioned Aeromonas saline-alkali.

[0022] Specifically, in some embodiments of the present invention, a seed culture is prepared by inoculating the *Aeromonas sanleriensis* in LB liquid medium and culturing it at 30°C and 180 rpm for 12 h with shaking. Then, the seed culture is inoculated into LB liquid medium at a 1% v / v inoculation rate and cultured for 24 h to obtain a bacterial culture (~10). 8(CFU / ml); After 5 days of normal growth, each pot of sweet potato seedlings was irrigated with 50 mL of bacterial solution, while the control group was irrigated with an equal volume of sterile culture medium. Fourteen days later, bacterial solution and an equal volume of sterile culture medium were applied again. The soil salinity and available phosphorus content after sweet potato harvest were measured, indicating that *Aeromonas sanguinis* has good salt-reducing and phosphorus-dissolving capabilities in coastal saline-alkali soils, demonstrating its application potential in the preparation of coastal saline-alkali soil conditioners.

[0023] Furthermore, a plant growth promoter for coastal saline-alkali soil, wherein the promoter contains the aforementioned Aeromonas saline-alkali.

[0024] Specifically, in some embodiments of the present invention, a seed culture is prepared by inoculating the *Aeromonas sanleriensis* in LB liquid medium and culturing it at 30°C and 180 rpm for 12 h with shaking. Then, the seed culture is inoculated into LB liquid medium at a 1% v / v inoculation rate and cultured for 24 h to obtain a bacterial culture (~10). 8 (CFU / ml); After 5 days of normal growth, each pot of sweet potato seedlings was watered with 50mL of bacterial solution, while the control group was watered with an equal volume of sterile culture medium. 14 days later, bacterial solution and an equal volume of sterile culture medium were applied again. The aboveground biomass, vine length, stem diameter, total phosphorus, total potassium, and sodium content of the sweet potato plants were then compared after harvest. + The results of the K assay showed that Aeromonas sanguinis significantly promoted the growth of sweet potato in coastal saline-alkali soil, demonstrating the application potential of Aeromonas sanguinis in the preparation of plant growth promoters in coastal saline-alkali soil.

[0025] The aforementioned coastal saline-alkali soil refers to moderately saline-alkali coastal soil with a soluble salt content of 2–4 g / kg.

[0026] Beneficial effects:

[0027] (1) This invention discovers and preserves a salt-tolerant strain of Aeromonas saline-alkali bacteria P1-5 for the first time. This strain has nitrogen-fixing, phosphorus-solubilizing, and growth-promoting properties, and can grow normally under 2% NaCl culture conditions, providing a new type of microbial resource for the treatment of coastal saline-alkali soil.

[0028] (2) Multiple functions and high efficiency: The strain P1-5 provided by this invention not only has the effect of reducing salt and dissolving phosphorus in coastal saline-alkali soil, but also significantly increases the absorption of nutrients such as nitrogen and phosphorus, enhances the salt tolerance and stress resistance of plants, and promotes plant growth. This strain has broad application prospects in saline-alkali land improvement and plant growth promotion and stress resistance.

[0029] (3) Environmentally friendly: The strain P1-5 provided by this invention is an indigenous microorganism screened from coastal saline-alkali soil. It is easy to adapt to the soil environment, has the characteristics of low cost and green environmental protection, and will not cause pollution to the environment. Attached Figure Description

[0030] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, and the advantages of the present invention in the above and / or other aspects will become clearer.

[0031] Figure 1 The colony morphology of strain P1-5 of the present invention and its morphology under a microscope;

[0032] Figure 2 The cell morphology of strain P1-5 of the present invention after Gram staining under a microscope;

[0033] Figure 3 The effects of strain P1-5 of this invention on the salinity and available phosphorus content of coastal saline-alkali soils;

[0034] Figure 4 The effects of strain P1-5 of this invention on the growth indicators of sweet potato in coastal saline-alkali soil;

[0035] Figure 5 The present invention relates to the effects of strain P1-5 on nitrogen, phosphorus, and Na+ in sweet potato plants grown in coastal saline-alkali soil. + / K + The impact. Detailed Implementation

[0036] Unless otherwise specified, the experimental methods described in the following examples are conventional methods; unless otherwise specified, the reagents and materials are commercially available.

[0037] Example 1: Isolation, screening and identification of strain P1-5

[0038] (1) Rhizosphere soil collection: Rhizosphere soil of crops was collected from soils with different salinities at Jinhai Farm, Dafeng District, Yancheng (120.493°E, 32.594°N). The collected rhizosphere soil was packed into self-sealing bags and brought back to the laboratory and stored at 4℃.

[0039] (2) Initial screening of bacterial strains: After passing the soil sample through a 10-mesh sieve (approximately 2 mm in diameter), weigh 5 g of rhizosphere soil sample in a sterile laminar flow hood and place it in a conical flask containing 45 ml of sterile water (with 7-8 sterile glass beads in the flask). Shake at 180 r / min on a shaker at a constant temperature of 25°C for 30 min. After standing for 10 min, obtain 10... -1 The soil sample was diluted. 0.5 ml of the diluted solution was pipetted into the solution. -1 The sample dilution was placed in a centrifuge tube containing 4.5 ml of sterile water and shaken well to obtain 10. -2 The sample dilution was prepared by serially diluting it to 10⁻⁶ using this concentration gradient method. -3 10 -4 10 -5 10 -6The sample dilutions were prepared. 100 μL of each gradient was spread onto beef extract peptone solid medium, with each concentration repeated three times. The plates were incubated upside down in a 30°C incubator for 48 hours. Single colonies of different morphologies were then picked from the solid medium and inoculated onto fresh beef extract peptone solid medium. The bacterial growth was observed every 24 hours. The culture was purified at least five times until healthy single colonies were formed. These single colonies were then inoculated onto beef extract peptone solid medium and stored at 4°C for later use.

[0040] The formula for the beef extract peptone solid culture medium is as follows: 10g peptone, 5g sodium chloride, 3g beef extract powder, 15g agar, 1L water, pH 7.2-7.4; sterilized at 121℃ for 20min.

[0041] (3) Secondary screening of strains: To screen for salt-tolerant microorganisms, all initially screened bacteria were inoculated into sterile LB liquid medium for batch activation. Beef extract peptone solid medium with NaCl concentrations of 2%, 4%, 6%, 8%, and 10% (wt%) was prepared, and the activated strains were streaked onto plates and incubated at 30℃ for 24–48 h. The growth of the strains was observed and the results were recorded to determine their salt tolerance. Colonies growing within 48 h were considered tolerant; no colonies growing indicated intolerance.

[0042] The formula for the NaCl-containing beef extract peptone solid culture medium is as follows: 10g peptone, 5g sodium chloride, 3g beef extract powder, 15g agar, and 1L water. Then, 2%, 4%, 6%, 8%, and 10% (wt%) of NaCl are added respectively, with a pH of 7.2–7.4; sterilized at 121℃ for 20 minutes.

[0043] The above LB liquid culture medium formula is: 10g tryptone, 5g yeast extract, 10g NaCl, 1L water, pH 7.0; sterilize at 121℃ for 20min.

[0044] (4) Strain purification and preservation: The isolated and purified strain was inoculated into 25 ml of LB liquid medium and cultured overnight at 30°C with shaking at 150 r / min. The cultured bacterial solution was mixed with 50% glycerol at a ratio of 1:1 in a 2 ml centrifuge tube and stored in an ultra-low temperature freezer at -80°C.

[0045] (5) Morphological identification of the strain: The purified strain P1-5 was selected and cultured on beef extract peptone agar using the streak plate method at 30°C for 1 day. The colony morphology was observed as follows. Figure 1 As shown. The colonies are smooth, round, pale yellow, opaque, and easy to pick up. Microscopic examination reveals them to be Gram-negative bacteria. Figure 2 ).

[0046] (6) Molecular biological identification of the strain: DNA was extracted from the screened strain P1-5 and amplified using the strain as a template with universal bacterial primers 27F (SEQ ID No. 2: 5'-AGAGTTTGATCCTGGCTCAG-3') and 1492R (SEQ ID No. 3: 5'-TACGGTTACCTTGTTACGACTT-3'). The amplified DNA was then sequenced by Nanjing Jisi Huiyuan Biotechnology Co., Ltd. The 16S rDNA nucleotide sequence obtained is shown in SEQ ID NO. 1. The sequenced sequence was compared for homology in the NCBI database (https: / / blast.ncbi.nlm.nih.gov / Blast.cgi). The results showed that strain P1-5 had a similarity of 99.65% with Aeromonas sanarellii strain HAE1. Therefore, this invention has successfully isolated and purified a strain of Aeromonas sanarellii, P1-5.

[0047] (7) Preservation of strain: Aeromonas sauris P1-5 was deposited at the China General Microbiological Culture Collection Center (CGMCC) on October 31, 2024. The strain was classified as Aeromonas sauris, strain number P1-5, preservation number CGMCC No.32451, and the deposit address is No.3, No.1 Beichen West Road, Chaoyang District, Beijing.

[0048] Example 2: Analysis of growth-promoting characteristics of strain P1-5

[0049] Single colonies of the isolated strain P1-5 were transferred to Erlenmeyer flasks containing 25 mL of liquid culture medium and cultured at 30 °C with shaking at 150 rpm for 24 h to obtain seed culture. The nitrogen fixation, inorganic phosphorus solubilization, potassium solubilization, siderophore production, indoleacetic acid (IAA) production, and 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase production abilities of strain P1-5 were determined.

[0050] (1) Nitrogen fixation capacity test: 10 μL of seed liquid was inoculated onto Ashby nitrogen-free medium and incubated upside down in a 30°C constant temperature incubator for 7 days. The colonies were observed to see if they could grow normally on the nitrogen-free medium.

[0051] (2) Test of inorganic phosphorus solubility: Take 10 μL of seed liquid and spot it onto inorganic phosphorus solid culture medium. Incubate in an inverted incubator at 30°C for 7 days and observe whether a degradation transparent zone is generated around the colony.

[0052] (3) Potassium solubilization capacity test: Take 10uL of seed liquid and spot it onto silicate bacteria culture medium. Incubate in an inverted incubator at 30℃ for 7 days and observe whether a degradation transparent zone is produced on the culture medium.

[0053] (4) Test of siderophore production capacity: Take 10uL of seed liquid and spot it onto CAS test medium. Incubate in an inverted incubator at 30℃ for 7 days and observe whether a yellow halo appears on the medium.

[0054] (5) IAA production capacity test: Take 0.5 ml of seed culture and add it to 25 mL of liquid culture medium (the liquid culture medium is a mixture of YN liquid culture medium and 2.5 mg / mL tryptophan in a 4:1 ratio). Incubate at 30℃ and 180 r / min for 48 h. After 48 h, take 1 ml of culture medium and centrifuge at 4℃ and 8000 r / min for 10 min. After centrifugation, take 200 μl of supernatant and add 400 μl of Salkowski colorimetric reagent. Let it stand in the dark for 30 min and observe whether a colorimetric reaction occurs. If a red color appears, it indicates that it has the ability to produce IAA.

[0055] (6) Detection of ACC deaminase production capacity: Take 0.5 ml of seed culture and inoculate it into 25 mL of YN liquid medium. After 3 days at 30℃ and 150 r / min, take another 0.5 ml of culture medium and transfer it into 5 ml of DF and 5 ml of ADF liquid medium respectively. After culturing for one day each, after centrifugation, measure the absorbance of the supernatant at 540 nm. If the growth of the strain in ADF medium is significantly better than that in DF medium, it indicates that the strain has the ability to produce ACC deaminase.

[0056] The above Ashby nitrogen-free medium consists of: 0.2g potassium dihydrogen phosphate, 0.2g magnesium sulfate, 0.2g sodium chloride, 5.0g calcium carbonate, 10.0g mannitol, 0.1g calcium sulfate, 15g agar, 1L deionized water, and pH 6.9–7.1.

[0057] The above-mentioned inorganic phosphorus solid culture medium consists of: 10.0g glucose, 0.5g ammonium sulfate, 0.5g yeast extract, 0.3g sodium chloride, 0.3g potassium chloride, 0.3g magnesium sulfate, 0.03g ferrous sulfate, 0.03g manganese sulfate, 5.0g tricalcium phosphate, 15g agar, and 1L deionized water, with a pH of 7.0–7.5; sterilized at 121℃ for 15 minutes.

[0058] The above-mentioned silicate bacteria culture medium consists of: 5.0g sucrose, 0.5g magnesium sulfate, 0.1g calcium carbonate, 2.0g disodium hydrogen phosphate, 0.005g ferric chloride, 1.0g glass powder, 15.0g agar, and 1L deionized water, with a pH of 6.8–7.2; sterilized at 121℃ for 15min.

[0059] The CAS detection medium composition was as follows: 0.0605g Chromium Azurite S, 0.0729g hexadecyltrimethylammonium bromide, 0.00265g ferric chloride hexahydrate, 0.295g sodium dihydrogen phosphate dihydrate, 1.214g sodium dihydrogen phosphate dodecahydrate, 0.125g ammonium chloride, 0.0375g potassium dihydrogen phosphate, 0.0625g sodium chloride, 15g agar, and 1L deionized water, pH 6.7–6.9; sterilized at 115℃ for 30min.

[0060] The above YN liquid culture medium consists of: 10.0g sucrose, 0.5g yeast extract, 0.1g sodium chloride, 1.0g ammonium sulfate, 1.0g dipotassium hydrogen phosphate, 0.5g magnesium sulfate heptahydrate, 1L deionized water, pH 7.2; sterilized at 121℃ for 20min.

[0061] The preparation method of Salkowaki colorimetric reagent is as follows: add 7.5 mL of 0.5 mol / L ferric chloride hexahydrate to 150 mL of sulfuric acid, and then add 250 mL of deionized water.

[0062] The above-mentioned DF liquid culture medium consists of: 4g potassium dihydrogen phosphate, 6g disodium hydrogen phosphate, 0.2g magnesium sulfate heptahydrate, 2g glucose, 2g gluconic acid, 2g citric acid, 0.01mg boric acid, 0.0112mg magnesium sulfate, 0.1246mg zinc sulfate, 0.0782mg copper sulfate, 0.01mg molybdenum trioxide, 1.0mg ferrous sulfate heptahydrate, and 1L deionized water; sterilized at 121℃ for 20min.

[0063] The composition of the above ADF liquid culture medium is as follows: 4g potassium dihydrogen phosphate, 6g disodium hydrogen phosphate, 0.2g magnesium sulfate heptahydrate, 2g glucose, 2g gluconic acid, 2g citric acid, 5.0mmol / L ACC stock solution, 0.01mg boric acid, 0.0112mg magnesium sulfate, 0.1246mg zinc sulfate, 0.0782mg copper sulfate, 0.01mg molybdenum trioxide, 1.0mg ferrous sulfate heptahydrate, and 1L deionized water; sterilized at 121℃ for 20min.

[0064] The results of the strain growth promotion ability test (Table 1) showed that strain P1-5 had good nitrogen fixation, inorganic phosphorus dissolution, siderophore production and IAA production abilities, while strain P1-5 did not show significant effects in potassium solubilization and ACC deaminase production.

[0065] Table 1. Growth-promoting ability of strain P1-5

[0066] P1-5 + + - + + -

[0067] Note: "+" means "present", and "-" means "absent".

[0068] Example 3: Application of the strain in coastal saline-alkali soil for salt reduction, phosphorus solubilization, and growth promotion.

[0069] (1) Pot Experiment: The test soil was collected from the Tiaozini Reclamation Area of ​​Dongtai Town, Yancheng City, Jiangsu Province. The soil type was coastal saline-alkali soil, with a pH of 8.99, a salt content of 2.38 g / kg, an organic matter content of 4.92 g / kg, a total nitrogen content of 0.33 g / kg, an available phosphorus content of 17.69 mg / kg, and a available potassium content of 242.50 mg / kg. After air-drying and sieving (2 mm), the soil was placed in plastic pots with a diameter of 13 cm and a height of 12 cm, with 2 kg per pot. The test plants were Xushu 51, with 2 cuttings of uniform growth in each pot. The experiment set up two treatments: no bacterial culture (CK) and inoculation with bacterial solution (P1-5) alone. Each treatment was repeated 3 times.

[0070] (2) Preparation of bacterial culture: Strain P1-5 was inoculated into 25 mL of LB liquid medium and cultured at 30℃ and 180 r / min for 12 h to obtain seed culture. Then, 1% of the seed culture was inoculated into 200 mL of LB liquid medium and cultured for 24 h before use (~10) 8 (CFU / ml).

[0071] (3) Five days after the sweet potato seedlings began to grow normally, each pot was irrigated with 50 mL of bacterial solution, while the control group was irrigated with an equal volume of sterile culture medium. Fourteen days later, another 50 mL of bacterial solution and an equal volume of sterile culture medium were applied. During this period, watering and weeding were carried out regularly. The potted plants were grown in a greenhouse at the Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences. Watering was applied appropriately and timely in the later stages to maintain soil moisture at 60% field capacity. Sweet potatoes were harvested and sampled after 42 days of growth. Aboveground biomass, vine length, stem diameter, total phosphorus, total potassium, and sodium content were measured. + / K + As well as soil salinity and available phosphorus content. Results are as follows: Figures 3-5 As shown.

[0072] Compared with the uninoculated control, application of P1-5 bacterial solution significantly reduced the salinity of coastal saline-alkali soil by 14.5% and significantly increased the available phosphorus content by 6.3%. Figure 3 This indicates that strain P1-5 has good salt reduction and phosphorus dissolution capabilities in coastal saline-alkali soil.

[0073] Compared with the uninoculated control, application of P1-5 bacterial solution significantly increased the aboveground biomass dry weight of sweet potato by 42.9%, and significantly increased vine length and stem diameter by 37.4% and 34.4%, respectively. Figure 4 The results indicate that strain P1-5 can significantly promote the growth of sweet potato in coastal saline-alkali soil.

[0074] Compared with the uninoculated control, application of P1-5 bacterial solution significantly increased the total nitrogen and total phosphorus content of plants by 8.3% and 23.5%, respectively, and reduced the Na content in the plants. + / K+ A significant decrease of 37.6% ( Figure 5 This indicates that strain P1-5 can not only significantly promote the absorption of nitrogen and phosphorus nutrients in sweet potatoes and improve their mineral nutritional status, but also reduce Na+. + / K + This method can increase the salt tolerance and stress resistance of sweet potatoes, and alleviate the adverse effects of salt on sweet potato growth.

[0075] In summary, the *Aeromonas saline-alkali* strain P1-5, screened from coastal saline-alkali soils in this study, possesses nitrogen fixation, phosphorus solubilization, siderophore production, and IAA production capabilities. Potato pot experiments showed that under saline-alkali conditions, strain P1-5 not only effectively reduced soil salinity and increased available phosphorus content, but also significantly improved sweet potato biomass, vine length, stem diameter, and other growth indicators, improved plant nutrition, increased nitrogen and phosphorus absorption, and simultaneously reduced sodium levels within the plant. + / K + The ratio enhances the salt tolerance of sweet potatoes.

[0076] This invention provides a strain of Aeromonas sauris and its applications. Many methods and approaches exist for implementing this technical solution; the above description is merely a preferred embodiment. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention. All components not explicitly stated in this embodiment can be implemented using existing technologies.

Claims

1. A strain of Aeromonas saurischia, characterized in that, Category naming Aeromonas sanarellii The strain number is P1-5, which was deposited at the China General Microbiological Culture Collection Center on October 31, 2024, with the accession number CGMCC No. 32451.

2. The application of Aeromonas saline-alkali as described in claim 1 in the improvement of coastal saline-alkali soil; characterized in that, The coastal saline-alkali soil is a moderately saline-alkali coastal soil with a soluble salt content of 2-4 g / kg; the coastal saline-alkali soil improvement in the application is to reduce the soil salinity and / or increase the available phosphorus content of the soil.

3. The application of Aeromonas saline-alkali as described in claim 1 in promoting plant growth in coastal saline-alkali soils; characterized in that, The coastal saline-alkali soil is a moderately saline-alkali coastal soil with a soluble salt content of 2-4 g / kg; the plant is sweet potato; the application includes at least one of the following: The application of Aeromonas saline-alkali in promoting the growth of sweet potato plant biomass, vine length and stem diameter in coastal saline-alkali soil. The application of Aeromonas saline-alkali in promoting nitrogen and phosphorus nutrient absorption by sweet potato plants in coastal saline-alkali soil. The *Aeromonas sanrelii* strain reduced Na+ in sweet potato plants in coastal saline-alkali soil. + / K + Compared to other methods, this increases the application of salt tolerance and stress resistance in sweet potato plants.

4. A coastal saline-alkali soil conditioner, characterized in that, The amendment contains Aeromonas saline as described in claim 1; the coastal saline-alkali soil is a moderately saline-alkali coastal soil with a soluble salt content of 2-4 g / kg; the amendment is used to reduce soil salinity and / or increase soil available phosphorus content.

5. A plant growth promoter for coastal saline-alkali soil, characterized in that, The growth promoter contains Aeromonas saline as described in claim 1; the coastal saline-alkali soil is a moderately saline-alkali coastal soil with a soluble salt content of 2-4 g / kg; the plant is sweet potato; the growth promoter is used in at least one of the following applications: The growth promoter is used to promote the growth of sweet potato plant biomass, vine length and stem diameter in coastal saline-alkali soil. The application of the growth promoter in promoting the absorption of nitrogen and phosphorus nutrients by sweet potato plants in coastal saline-alkali soil; The growth promoter reduces the Na+ content of sweet potato plants in coastal saline-alkali soil. + / K + Compared to other methods, this increases the application of salt tolerance and stress resistance in sweet potato plants.

Images