Salt-tolerant strain 8A-1 and application thereof

Abstract

The invention provides a salt-tolerant strain 8A-1 and application thereof, and relates to the technical field of microorganisms. The salt-tolerant strain 8A-1 obtained through screening can survive in the environment with the NaCl concentration being 16% and the pH value being 8.5, and the soil index of the saline-alkali soil can be effectively improved and the EC value and the pH value of the soil can be reduced by spraying a bacteria solution of the salt-tolerant strain 8A-1 in the saline-alkali soil. The salt-tolerant strain 8A-1 can remarkably improve the yield of cotton in saline-alkali soil, effectively relieves or relieves salt stress of the growth environment on cotton plants, lays a foundation for promoting and improving cotton growth, and has high application value in cotton planting.

Description

Technical Field

[0001] The invention relates to the technical field of microorganisms, and in particular to a salt-tolerant bacterial strain 8A-1 and an application thereof. Background Art

[0002] At present, soil salinization has become an important limiting factor for the sustainable development of world agriculture. By improving the physical and chemical properties of soil, improving water use efficiency, and improving saline-alkali land resources, saline-alkali land resources can be efficiently utilized, which has important scientific and theoretical significance for adjusting and cultivating new industrial planting areas for cash crops and for economic development.

[0003] With the growth of domestic and foreign demand for cotton since the late 1980s, and the relative salt tolerance of cotton, cotton has become the main crop grown in saline-alkali land. During the cultivation of cotton fields in saline-alkali land, salt gradually accumulates because the evaporation of the soil is far greater than the irrigation water and rainfall. In addition, due to the long-term use of inorganic fertilizers (chemical fertilizers) and little or no application of organic fertilizers, not only the physical and chemical properties of the soil have deteriorated, the aeration and fertilizer absorption capacity have deteriorated, but also the nitrogen, phosphorus and potassium ratios have been imbalanced, cotton has grown poorly, and the stability and sustainability of cotton production have become increasingly poor. Therefore, in order to ensure the sustainable development of cotton fields, it is urgent to accelerate the development of saline-alkali land improvement technology.

[0004] Halomonas bacteria play an important role in soil, especially in the treatment and degradation of various pollutants. This bacterium has the ability to adapt to extreme environments, such as salt tolerance and drought tolerance, which allows them to survive and reproduce in high-salt, arid soil environments. In particular, Halomonas bacteria show high abundance and activity in rare earth tailings ponds and petroleum-contaminated soils. These bacteria can play a role in treating petroleum pollution by secreting surfactants to help disperse and degrade hydrocarbons in the soil, such as those in petroleum. In addition, Halomonas bacteria can also adapt to environments with heavy accumulation of rare earth elements, which provides a potential solution for the remediation of contaminated soil in rare earth mining areas. However, there are no reports of Halomonas bacteria that can both improve saline-alkali land and promote cotton growth. Summary of the invention

[0005] The purpose of the present invention is to provide a salt-tolerant bacterial strain 8A-1 and its application, which can improve saline-alkali land and promote cotton growth.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] The present invention provides a salt-tolerant strain 8A-1, which is deposited in the General Microbiology Center of China Microorganism Culture Collection Administration, with a deposit number of CGMCC No.30799, a deposit date of May 28, 2024, and a deposit address of No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing.

[0008] The present invention also provides a fermentation method of the salt-tolerant strain 8A-1, which comprises inoculating the salt-tolerant strain 8A-1 into a fermentation medium for fermentation culture.

[0009] Preferably, the temperature of the fermentation culture is 28-32° C., the rotation speed of the fermentation culture is 160-200 rpm, and the time of the fermentation culture is 45-50 h.

[0010] The present invention also provides a microbial agent, which comprises the strain 8A-1, and the spore concentration in the microbial agent is 1 to 3×10 8 / L.

[0011] The present invention also provides the use of the salt-tolerant strain 8A-1 in all or part of the following (1) to (3):

[0012] (1) Application in improving saline-alkali land;

[0013] (2) Application in promoting cotton growth in light or heavy saline-alkali land;

[0014] (3) Application in the preparation of cotton growth promoters in light or heavy saline-alkali soils.

[0015] The present invention also provides a microbial fertilizer, which comprises the salt-tolerant strain 8A-1 and / or the microbial agent.

[0016] The present invention also provides a method for improving saline-alkali land, which comprises applying the salt-tolerant strain 8A-1, the microbial agent or the microbial fertilizer to the saline-alkali land soil.

[0017] The present invention also provides a method for promoting plant growth in saline-alkali land, which comprises applying the salt-tolerant strain 8A-1, the microbial agent or the microbial fertilizer to soil where the plants grow.

[0018] Preferably, the plant comprises cotton.

[0019] By adopting the above technical scheme, the present invention has the following beneficial effects: the salt-tolerant strain 8A-1 screened by the present invention can survive in an environment with a NaCl concentration of 16% and a pH of 8.5, and spraying the bacterial solution of the salt-tolerant strain 8A-1 in saline-alkali soil can effectively improve the soil indicators of the saline-alkali land and reduce the EC value and pH value of the soil. The salt-tolerant strain 8A-1 of the present invention can significantly improve the survival rate of cotton in saline-alkali land, effectively alleviate or relieve the salt stress of the growth environment on cotton plants, lay a foundation for increasing cotton yield, and has a high application value in cotton planting. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is the colony picture of the salt-tolerant strain 8A-1 after culturing for 4 days.

[0021] Figure 2 This is the sequence alignment of the salt-tolerant strain 8A-1 on NCBI.

[0022] Figure 3 This is a diagram showing the effect of the salt-tolerant strain 8A-1 in promoting cotton growth in mild saline-alkali land.

[0023] Biological Deposit Description

[0024] The salt-tolerant strain provided by the present invention is Halomonas sp. 8A-1, which is deposited in the General Microbiological Center of China National Microbiological Culture Collection Committee, with a deposit number of CGMCC No. 30799, a deposit date of May 28, 2024, and a deposit address of No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing. DETAILED DESCRIPTION

[0025] The present invention provides a salt-tolerant strain 8A-1, which is deposited in the General Microbiology Center of China Microorganism Culture Collection Administration, with a deposit number of CGMCC No.30799, a deposit date of May 28, 2024, and a deposit address of No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing.

[0026] The present invention also provides a fermentation method of the salt-tolerant strain 8A-1, which comprises inoculating the salt-tolerant strain 8A-1 into a fermentation medium for fermentation culture. The fermentation culture temperature is 28 to 32°C, more preferably 29 to 31°C, and more preferably 30°C; the fermentation culture rotation speed is 160 to 200rpm, more preferably 170 to 190rpm, and more preferably 180rpm; the fermentation culture time is 45 to 50h, more preferably 46 to 49h, and more preferably 48h.

[0027] The present invention also provides a microbial agent, which comprises the strain 8A-1, and the spore concentration in the microbial agent is 1 to 3×10 7 / L, more preferably 1.5 to 2.5×10 8 / L, more preferably 2×10 8 / L.

[0028] The present invention also provides the use of the salt-tolerant strain 8A-1 in all or part of the following (1) to (3):

[0029] (1) Application in improving saline-alkali land;

[0030] (2) Application in promoting cotton growth in light or heavy saline-alkali land;

[0031] (3) Application in the preparation of cotton growth promoters in light or heavy saline-alkali soils.

[0032] The present invention also provides a microbial fertilizer, which comprises the salt-tolerant strain 8A-1 and / or the microbial agent.

[0033] The present invention also provides a method for improving saline-alkali land, which comprises applying the salt-tolerant strain 8A-1, the microbial agent or the microbial fertilizer to the saline-alkali land soil.

[0034] The present invention also provides a method for promoting plant growth in saline-alkali land, which comprises applying the salt-tolerant strain 8A-1, the microbial agent or the microbial fertilizer to soil where the plants grow; the plants include cotton.

[0035] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0036] Example 1 Strain Isolation and Purification

[0037] Preparation of LB liquid medium:

[0038] LB liquid medium (NaCl 5%, pH 8.5): containing 10.0 g of tryptone, 5.0 g of yeast extract, 50.0 g of NaCl, fixed to 1 L with ddH2O, and adjusted to pH = 8.5 with NaOH 1 mol / L solution.

[0039] LB liquid medium (NaCl 7%, pH 8.5): contains 10.0 g of tryptone, 5.0 g of yeast extract, 70.0 g of NaCl, and ddH2O to make up to 1 L, and adjusted to pH = 8.5 with NaOH 1 mol / L solution.

[0040] LB liquid medium (NaCl 10%, pH 8.5): containing 10.0 g of tryptone, 5.0 g of yeast extract, 100.0 g of NaCl, fixed to 1 L with ddH2O, and adjusted to pH = 8.5 with NaOH 1 mol / L solution.

[0041] LB liquid medium (NaCl 16%, pH 8.5): containing 10.0 g of tryptone, 5.0 g of yeast extract, 160.0 g of NaCl, fixed to 1 L with ddH2O, and adjusted to pH = 8.5 with NaOH 1 mol / L solution.

[0042] Samples were collected from saline-alkali soil in Qiketai Town, Shanshan, Xinjiang for bacterial isolation and purification.

[0043] Weigh 5 g of soil sample and add it to 100 mL of LB liquid culture medium (NaCl 5%, pH=8.5), and carry out enrichment culture at 30°C and 180 rpm for 7 days, which is recorded as the first generation.

[0044] The above culture solution was re-transferred into 100 mL LB liquid culture medium (NaCl 5%, pH=8.5) at a ratio of 2%, and cultured under the same conditions for 7 days, which was recorded as the second generation.

[0045] The second generation culture fluid was re-transferred into 100 mL LB liquid culture medium (NaCl 7%, pH=8.5) at a ratio of 2%, and cultured under the same conditions for 7 days, which was recorded as the third generation.

[0046] The third generation culture fluid was re-transferred into 100 mL LB liquid culture medium (NaCl 10%, pH=8.5) at a ratio of 2%, and cultured under the same conditions for 7 days, which was recorded as the fourth generation.

[0047] The fourth generation culture fluid was re-transferred into 100 mL LB liquid culture medium (NaCl 16%, pH=8.5) at a ratio of 2%, and cultured under the same conditions for 7 days, which was recorded as the fifth generation.

[0048] Use a sterile pipette tip to dip the fifth generation bacterial solution and streak it on LB solid medium (NaCl 16%, pH 8.5), and culture it at 30℃. After 2-3 days, a single colony will grow. Extract the genomic DNA of the strain and perform PCR amplification. Then perform 16S sequencing on the PCR amplification product to identify the strain. The morphology of strain 8A-1 after 4 days of culture is as follows Figure 1 shown.

[0049] The forward primer and reverse primer of PCR are shown as SEQ ID No.1 and SEQ ID No.2.

[0050] 27F: 5'-AGTTTGACMTGGCTCAG-3' (SEQ ID No. 1);

[0051] 1492R: 5'-CGGTTACCTTGTTACGACTT-3' (SEQ ID No. 2);

[0052] PCR system (49.5 μL): pick half of a single colony of the strain, Mix (2×Phanta MaxMaster Mix) 25 μL, primers 1492R and 27F 2 μL each, ultrapure water 20.5 μL;

[0053] The PCR program was: 95°C for 3 min; 95°C for 10 s, 60°C for 10 s, 72°C for 15 s, 35 cycles; 72°C for 10 min; 4°C forever.

[0054] The amplified product was sequenced for 16S rDNA, and the sequencing result is shown in SEQ ID No. 3. A BLAST comparison was performed on NCBI, and the comparison diagram is shown in Figure 2 As shown, the strain was identified as Halomonas sp.

[0055] SEQ ID No.3:

[0056]

[0057] Example 2

[0058] Preparation method of bacterial solution: transfer the bacteria stored on the slant into a test tube containing 5 mL LB liquid culture medium (NaCl 5%, pH = 8.5), and culture it in a constant temperature shaker for 48 hours at 30°C and 180 rpm; inoculate the activated bacterial solution into 50 mL LB liquid culture medium at a 1% inoculation rate, and culture it in a shaker for 16 hours at 37°C and 180 rpm to make a bacterial solution.

[0059] The experiment was conducted on May 30 in a mild saline-alkali land demonstration field in Dongying, Shandong. The mild saline-alkali land demonstration field was sprayed with a 500-fold diluted bacterial solution at a spraying rate of 25L / mu, and the mild saline-alkali land demonstration field without bacterial solution was used as a control. Each group of experimental fields planted cotton at a density of 2041 plants / mu, and the soil physical and chemical properties, microbial counts, and vegetation growth of the experimental fields were monitored on October 28. The results are shown in Tables 1 and Figure 3 By comparing and analyzing the monitoring data of different treatment groups, the effects of strain inoculation and organic fertilizer improvement on saline-alkali land improvement were evaluated.

[0060] Table 1 Soil and crop indicators for saline-alkali land improvement

[0061]

[0062] The yield measurement results showed that the mechanized yield of the mild saline-alkali land demonstration field after spraying the bacterial solution was 239.44 kg / mu, which was 84% ​​higher than the yield per mu of the control treatment (129.98 kg / mu). This shows that the salt-tolerant strain of the present invention has significant application value in cotton cultivation.

[0063] It can be seen from the above embodiments that the present invention provides a salt-tolerant strain 8A-1 and its application. The salt-tolerant strain of the present invention can significantly improve the survival rate of cotton in saline-alkali land in a saline-alkali environment, lays a foundation for increasing cotton yield, and has significant application value in cotton cultivation.

[0064] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A salt-tolerant strain 8A-1, It is characterized in that It is deposited in the General Microbiology Center of China Microorganism Culture Collection Administration, with the deposit number CGMCC No.30799, the deposit date is May 28, 2024, and the deposit address is No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing.

2. The fermentation method of the salt-tolerant strain 8A-1 according to claim 1, It is characterized in that The salt-tolerant strain 8A-1 is inoculated into a fermentation medium for fermentation culture.

3. The fermentation method according to claim 2, It is characterized in that The temperature of the fermentation culture is 28-32° C., the rotation speed of the fermentation culture is 160-200 rpm, and the time of the fermentation culture is 45-50 hours.

4. A microbial agent, It is characterized in that The microbial agent comprises the strain 8A-1 according to claim 1, and the spore concentration in the microbial agent is 1 to 3×10 8 / L.

5. Use of the salt-tolerant strain 8A-1 according to claim 1 in all or part of the following (1) to (3): (1) Application in improving saline-alkali land; (2) Application in promoting cotton growth in slightly saline-alkali land; (3) Application in the preparation of cotton growth promoters in slightly saline-alkali soil.

6. A microbial fertilizer, It is characterized in that The microbial fertilizer comprises the salt-tolerant strain 8A-1 according to claim 1 and / or the microbial agent according to claim 4.

7. A method for improving saline-alkali land, It is characterized in that The salt-tolerant strain 8A-1 according to claim 1, the microbial agent according to claim 4 or the microbial fertilizer according to claim 6 is applied to saline-alkali soil.

8. A method for promoting plant growth in saline-alkali land, It is characterized in that The salt-tolerant strain 8A-1 according to claim 1, the microbial agent according to claim 4 or the microbial fertilizer according to claim 6 is applied to the soil where the plants grow.

9. The method according to claim 8, It is characterized in that The plants include cotton.

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