Pseudomonas syringae FJ-3, bacterial agent and application thereof

Abstract

The present invention belongs to the technical field of biological microbial agents, and specifically relates to a kind of Pseudomonas sargentii FJ‑3, a microbial agent and its application. The Pseudomonas sargentii FJ‑3 of the present invention is easy to culture and has a fast reproduction speed. On this basis, the Pseudomonas sargentii FJ‑3 and its microbial agent of the present invention can effectively improve the germination rate and emergence rate of plant seeds under salt stress, promote the growth of plant seedlings, and then achieve the ability of improving the plant's resistance to salt stress, and at the same time can effectively increase the yield of the plant; the microbial agent containing Pseudomonas sargentii FJ‑3 is promoted and used in the agricultural field by seed coating or foliar spraying, and provides technical support for the development of functional microbial preparations with salt stress resistance and growth promotion functions, and is of great significance.

Description

Technical Field

[0001] The invention belongs to the technical field of biological microbial agents, and particularly relates to Pseudomonas syringae FJ-3, a microbial agent and applications thereof. Background Art

[0002] There are many microorganisms in the ocean that can decompose kelp, and they can maintain strong activity in high-salinity environments (more than 5%). Pseudomonas hibiscicola ) is a Proteobacteria, Proteobacteria, Pseudomonas, Pseudomonas, Pseudomonas genus, Pseudomonas syringae, and is a bacterium widely distributed in soil and oceans (such as kelp, seaweed, coral and anemone). This microorganism has received widespread attention due to its strong salt tolerance, fast growth rate and strong adaptability.

[0003] Related studies have shown that Pseudomonas hibiscicola has the ability to remove Ni(II), Cr(VI), Cu(II) and nitrate from wastewater (An, Q., et al., Ni(II), Cr(VI), Cu(II) and nitrate removal by the co-system of Pseudomonas hibiscicola strain L1 immobilized on peanut shellbiochar. Science of the Total Environment, 2021); in addition, studies have shown that Pseudomonas hibiscicola has the ability to fix nitrogen (Ramos, PL, et al., Screening for endophytic nitrogen-fixing bacteria in Brazilian sugar cane varieties used in organic farming and description of Stenotrophomonas pavanii sp. nov. International Journal ofSystematic and Evolutionary Microbiology, 2011); in addition, studies have shown that Pseudomonas hibiscicola has the ability to produce auxins and solubilize phosphates (Ayangbenro, AS, MR Adem and OOBabalola, Bambara Nut Root-Nodules Bacteria from a Semi-Arid Region of South Africa and Their Plant Growth-Promoting Traits. International Journal of Microbiology, 2023). However, there are no reports on the application of Pseudomonas syringae in agriculture in terms of salt resistance and growth promotion. Summary of the invention

[0004] The object of the present invention is to provide a Pseudomonas aeruginosa FJ-3, a bacterial agent and an application thereof. The Pseudomonas aeruginosa FJ-3 can effectively improve the ability of plants to resist salt stress and promote the growth of plants.

[0005] The invention provides a Pseudomonas sargentii FJ-3. The preservation number of the Pseudomonas sargentii FJ-3 is CGMCC No.30327, and the preservation unit is the General Microbiology Center of China National Committee for the Preservation of Microbiological Cultures.

[0006] The present invention also provides a bacterial agent containing the Pseudomonas syringae FJ-3 described in the above technical solution.

[0007] Preferably, the bacterial agent includes a fermentation broth of Pseudomonas aeruginosa FJ-3 and / or a bacterial suspension containing Pseudomonas aeruginosa FJ-3.

[0008] Preferably, the effective viable count of Pseudomonas aeruginosa FJ-3 in the bacterial agent is 10 7 ~10 8 CFU / mL.

[0009] The present invention also provides the use of the bacterial agent described in the above technical solution in one or more of improving the salt stress tolerance of plants, promoting plant growth and preparing seed coating agents.

[0010] Preferably, the plant comprises a monocotyledonous plant.

[0011] Preferably, the plants include wheat and / or corn.

[0012] Preferably, the promoting plant growth comprises one or more of increasing the germination rate of seeds, increasing the emergence rate of plants, promoting the growth of plant seedlings and increasing plant yield.

[0013] The present invention also provides a method for improving plant salt stress tolerance and / or promoting plant growth, comprising any one of the following two items:

[0014] 1) Planting the plant seeds after coating them with the bacterial agent described in the above technical solution;

[0015] 2) Spraying the bacterial agent described in the above technical solution onto the plant seedlings.

[0016] Preferably, the seed coating comprises: soaking the plant seeds in a fungal agent.

[0017] Beneficial effects:

[0018] The present invention provides Pseudomonas sargentii FJ-3, and biological preservation has been completed. The Pseudomonas sargentii FJ-3 is easy to culture and has a fast reproduction speed. On this basis, the present invention also provides a bacterial agent containing the Pseudomonas sargentii FJ-3. The Pseudomonas sargentii FJ-3 and its bacterial agent can effectively improve the germination rate and emergence rate of plant seeds under salt stress, promote the growth of plant seedlings, and thus achieve the ability to improve the salt stress resistance of plants, and can effectively increase the yield of plants; the bacterial agent containing Pseudomonas sargentii is promoted and used in the agricultural field by seed coating or foliar spraying, and provides technical support for the development of functional microbial preparations with salt stress resistance and growth promotion functions, and is of great significance.

[0019] Biological deposit information

[0020] Pseudomonas syringae FJ-3, biological classification Pseudomonas hibiscicola , deposited on April 12, 2024 in the General Microbiology Center of China Microorganism Culture Collection (CGMCC), the deposit address is No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, Institute of Microbiology, Chinese Academy of Sciences, and the deposit number is CGMCC No.30327. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be used in the embodiments are briefly introduced below.

[0022] Figure 1 The enrichment and identification results of Pseudomonas syringae FJ-3 in Example 1 are shown in Figure 1, wherein (a) is a sample of the enrichment and fermentation of Laminaria japonica, (b) is a streaking colony, and (c) is a morphological image of the strain under a scanning electron microscope;

[0023] Figure 2 This is a comparison result diagram of Pseudomonas aeruginosa FJ-3 in Example 1 in NCBI;

[0024] Figure 3 The figures are the growth and physiological index result graphs of wheat seedlings in Example 3 and Comparative Example 1, wherein (a) to (e) are respectively the measurement result graphs of germination rate, fresh weight, dry weight, plant height and root length of wheat seedlings, and (f) to (l) are respectively the measurement result graphs of chlorophyll, catalase, superoxide dismutase, peroxidase, proline, malondialdehyde and hydrogen peroxide content in wheat seedlings;

[0025] Figure 4 The phenotype diagrams of wheat seedlings in Examples 3 to 4 and Comparative Examples 1 to 2, wherein (a) is the phenotype diagram of wheat seedlings in Example 3 and Comparative Example 1, and (b) is the phenotype diagram of wheat seedlings in Example 4 and Comparative Example 2;

[0026] Figure 5 The figures are the growth and physiological index result graphs of wheat seedlings in Example 4 and Comparative Example 2, wherein (a) to (e) are respectively the measurement result graphs of germination rate, fresh weight, dry weight, plant height and root length of wheat seedlings, and (f) to (l) are respectively the measurement result graphs of chlorophyll, catalase, superoxide dismutase, peroxidase, proline, malondialdehyde and hydrogen peroxide content in wheat seedlings;

[0027] Figure 6 The figures are the growth index result graphs of corn in Example 5 and Comparative Example 3, wherein (a) to (f) are the measurement result graphs of corn emergence rate, plant height, number of ear rows, number of kernels per row, 100-kernel weight and yield, respectively. DETAILED DESCRIPTION

[0028] The invention provides a Pseudomonas sargentii FJ-3. The preservation number of the Pseudomonas sargentii FJ-3 is CGMCC No.30327, and the preservation unit is the General Microbiology Center of China National Committee for the Preservation of Microbiological Cultures.

[0029] The Pseudomonas truncatum of the present invention was isolated from kelp obtained from the seashore of Dongying City, Shandong Province, China, and was confirmed to be Pseudomonas truncatum by colony characteristics and 16S rDNA sequence identification. The colony of Pseudomonas truncatum FJ-3 of the present invention on solid culture medium is white, has a smooth surface, and is Gram-negative. Figure 1 (b)], bacteria are observed under a microscope to be tubular and densely grown [ Figure 1

[0030] The present invention also provides a bacterial agent containing the Pseudomonas aeruginosa FJ-3 described in the above technical solution. The bacterial agent of the present invention preferably includes a fermentation broth of Pseudomonas aeruginosa FJ-3 and / or a bacterial suspension containing the Pseudomonas aeruginosa FJ-3, more preferably a fermentation broth of Pseudomonas aeruginosa FJ-3 or a bacterial suspension containing the Pseudomonas aeruginosa FJ-3. The effective viable count of Pseudomonas aeruginosa FJ-3 in the bacterial agent of the present invention is preferably 10 5 ~10 8 CFU / mL, more preferably 10 7 ~10 8 CFU / mL.

[0031] The method for preparing the fermentation broth of Pseudomonas aeruginosa FJ-3 of the present invention preferably comprises: inoculating Pseudomonas aeruginosa FJ-3 into a fermentation medium for fermentation culture to obtain the Pseudomonas aeruginosa FJ-3. The fermentation medium of the present invention preferably uses water as a solvent, and preferably comprises the following components in concentrations: 0.5-1.5 g / L of peptone, 0.5-1.5 g / L of yeast extract, 3-8 g / L of ammonium sulfate, 10-20 g / L of sodium chloride, and 20-100 mL / L of Weiss salt solution, more preferably the following components in concentrations: 1 g / L of peptone, 1 g / L of yeast extract, 5 g / L of ammonium sulfate, 15 g / L of sodium chloride, and 50 mL / L of Weiss salt solution, and the pH value is preferably 7-7.5, more preferably 7.5. The fermentation temperature of the present invention is preferably 20-35°C, more preferably 30°C; the fermentation speed is preferably 150-200 rpm, more preferably 180 rpm; the fermentation time is preferably 3-5 days, more preferably 3.5-4.5 days.

[0032] The method for preparing the bacterial suspension containing the Pseudomonas aeruginosa FJ-3 of the present invention preferably comprises: inoculating the Pseudomonas aeruginosa FJ-3 into a solid culture medium for expansion culture, washing the obtained Pseudomonas aeruginosa FJ-3 with sterile deionized water to obtain an initial bacterial suspension; diluting the initial bacterial suspension with sterile deionized water to obtain an effective viable bacterial count of 10 7 ~10 8 CFU / mL, and obtain the bacterial suspension containing the Pseudomonas aeruginosa FJ-3. The temperature of the expanded culture of the present invention is preferably 20-35°C, more preferably 30°C. The solid culture medium of the present invention is preferably added with 1.5% agar by mass percentage of the liquid culture medium on the basis of the liquid culture medium described in the above technical solution.

[0033] The Pseudomonas sibiricum FJ-3 of the present invention can be stably propagated in saline-alkali soils including coastal saline soils, and has the characteristics of being green, environmentally friendly, simple, convenient, safe and of high quality. The cultivation process of the Pseudomonas sibiricum FJ-3 is simple, the preparation cost of the microbial agent is low, and it is conducive to its promotion in agriculture.

[0034] The present invention also provides the use of the bacterial agent described in the above technical solution in one or more of improving the ability of plants to tolerate salt stress, promoting plant growth and preparing seed coating agents. The plants described in the present invention preferably include monocotyledons, and more preferably include wheat and / or corn. The promoting plant growth described in the present invention preferably includes: improving the germination rate of plant seeds, improving the emergence rate of plants, promoting the growth of plant seedlings and increasing plant yield. One or more of them are more preferably improving the germination rate of plant seeds, improving the emergence rate of plants, promoting the growth of plant seedlings and increasing plant yield; the promoting the growth of plant seedlings preferably includes increasing the fresh weight, dry weight, plant height, root length, number of ear rows, number of grains per row and one hundred grain weight of seedlings, and more preferably increasing the fresh weight, dry weight, plant height, root length and one hundred grain weight of seedlings. The invention relates to improving the ability of plants to tolerate salt stress, preferably including promoting plant growth under salt stress conditions, and preferably including increasing the chlorophyll content, catalase content, superoxide dismutase content, peroxidase content and proline content of plant seedlings under salt stress conditions, and reducing the malondialdehyde content and / or hydrogen peroxide content. The scope of promoting plant growth according to the invention is preferably the same as the above technical solution, and will not be repeated. The invention preferably uses the bacterial agent to infiltrate and coat plant seeds to achieve the purpose of improving the ability of plants to tolerate salt stress and promoting plant growth.

[0035] Under salt stress, applying a bacterial agent containing Pseudomonas syringae FJ-3 to plants can help plants maintain normal metabolism and growth under salt stress; in addition, antioxidant enzymes will reduce oxidative damage to cells by participating in the removal of free radicals in the plant body and reducing the content of reactive oxygen, thereby improving the adaptability of plants under salt stress. In addition, proline can alleviate the problem of osmotic accumulation caused by salt stress, help cells maintain normal osmotic regulation, maintain the stability of cell membranes, and ultimately improve plant growth and development. Finally, the reduction of malondialdehyde and hydrogen peroxide content in plants is of great significance for inhibiting cell oxidative damage and maintaining the stability of plant cells.

[0036] The present invention also provides a method for improving plant salt stress tolerance and / or promoting plant growth, comprising any one of the following two items: 1) coating plant seeds with the bacterial agent described in the above technical solution and then planting them; 2) spraying the bacterial agent described in the above technical solution on the leaves of plant seedlings.

[0037] The seed coating of the present invention preferably includes: soaking the plant seeds in the bacterial agent; the soaking time is preferably based on the soaking of the plant seeds. The spraying amount of the foliar spraying of the present invention is preferably such that the bacterial agent on the leaf surface no longer drips, and in practical applications, the foliar spraying is preferably sprayed once at the plant seedling stage.

[0038] In order to further illustrate the present invention, the technical solution provided by the present invention is described in detail below in conjunction with the accompanying drawings and embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0039] The culture medium used in the following examples and comparative examples:

[0040] Enrichment medium (g / L): fresh kelp pieces (1 cm 2 100 g of sodium sulfate, 5 g of ammonium sulfate, 15 g of sodium chloride, 50 mL of Weiss salt solution, pH 7.5. Weiss salt solution: K2HPO4·3H2O 6.50 g, MgSO4·7H2O 2.50 g, NaCl 2.50 g, FeSO4·7H2O 0.05 g, MnSO4·H2O 0.04 g, distilled water 1000 mL.

[0041] Liquid culture medium (g / L): peptone 1 g, yeast extract 1 g, ammonium sulfate 5 g, sodium chloride 15 g, Weiss salt solution 50 mL, pH 7.5.

[0042] Solid culture medium (g / L): Liquid culture medium plus 1.5% agar.

[0043] Example 1

[0044] The enrichment, isolation and identification of Pseudomonas syringae FJ-3 were carried out as follows:

[0045] Take 10 g of fresh kelp obtained from the seaside of Dongying City, Shandong Province, China, and place it in a 500 mL triangular flask containing 90 mL of enrichment medium, and culture it at 30°C and 180 rpm. Observe the turbidity of the culture solution and the residue of kelp every day. When the kelp shows 50% degradation, take 10 mL of the culture solution and transfer it to another 500 mL triangular flask containing 90 mL of enrichment medium, and continue to culture it at 30°C and 180 rpm. As above, observe every day, and when the kelp shows 50% degradation again, continue to transfer it to a new bottle of enrichment medium until the kelp shows 50% degradation within 3 days during the transfer process. Repeat the transfer again, and transfer it 3 times in total until a stable degrading bacterial community is obtained. The enrichment fermentation sample of kelp is shown in the figure below. Figure 1In (a), the two triangular bottles from left to right represent the degradation bacterial solution of the initial culture and the period when 50% degradation of Laminaria japonica occurred within 3 days (the final period).

[0046] The enriched bacterial solution was diluted 10 times and 10 8 0.1 mL of bacterial solution with CFU / mL was spread on solid culture medium plates, 4 plates for each dilution, and cultured at 30℃ for 1-2 days. Colonies were picked from the separation plates one by one for streaking purification. The streaking was performed three times continuously until a single pure colony was obtained, and then the strain was saved for later use. Figure 1 (b) The morphology of the bacteria under a scanning electron microscope Figure 1 Middle (c).

[0047] Depend on Figure 1 From (b) to (c), we can conclude that the colonies of this strain are white, with a smooth surface and Gram-negative. Under a microscope, the bacteria are tubular and densely grown.

[0048] The 16S rDNA sequence of the strain of the present invention is shown in SEQ ID NO.1, and the strain has a GenBank accession number of NR_024709.1. Pseudomonas hibiscicola The strains have 99.14% similarity ( Figure 2 ), therefore, the strain was identified as Pseudomonas aeruginosa based on the colony characteristics, and was deposited in the General Microbiology Center of China Microorganism Culture Collection Committee (CGMCC) and named as Pseudomonas aeruginosa FJ-3, with the deposit number of CGMCC No.30327.

[0049] Example 2

[0050] The preparation method of the bacterial agent containing Pseudomonas aeruginosa FJ-3 comprises the following steps:

[0051] 1) Preparation of Pseudomonas aeruginosa FJ-3 fermentation broth: Pseudomonas aeruginosa FJ-3 grown on solid culture medium was inoculated into liquid culture medium and cultured at 30°C and 180 rpm in a shaking incubator for 3-5 days until the effective viable bacterial concentration in the culture broth reached 10 7 ~10 8 CFU / mL, and the fermentation broth of Pseudomonas aeruginosa FJ-3 was obtained.

[0052] 2) Inoculate Pseudomonas aeruginosa FJ-3 onto solid culture medium and culture it in a sterile 30°C constant temperature incubator for 3-5 days. At this time, the colony morphology is moist, sticky, easy to pick up, and the surface is smooth. Then, the Pseudomonas aeruginosa FJ-3 strain grown on the solid culture medium is washed away with sterile deionized water to form an initial bacterial suspension, and then the initial bacterial suspension is diluted to 10 with sterile deionized water.7 ~10 8 CFU / mL, and the bacterial suspension of Pseudomonas aeruginosa FJ-3 was obtained.

[0053] Example 3

[0054] 1) After the wheat seeds were sterilized with 1% sodium hypochlorite for 10 dishes, the sterilized wheat seeds were immersed in the fermentation liquid of Pseudomonas aeruginosa FJ-3 prepared in Example 2 until they were soaked, thereby completing the coating of the wheat seeds.

[0055] 2) After potting the saline soil (EC: 6 dS / m, salt stress tolerance test was conducted according to Adil M, Bashir S, Bashir S, et al. Zinc oxide nanoparticles improved chlorophyll contents, physical parameters, and wheat yield under salt stress[J]. Frontiers in Plant Science, 2022.), the wheat seeds soaked in step 1) were planted in the saline soil.

[0056] Comparative Example 1

[0057] 1) After the wheat seeds are sterilized with 1% sodium hypochlorite for 10 dishes, the sterilized wheat seeds are immersed in sterile deionized water until they are soaked, thereby completing the coating of the wheat seeds.

[0058] 2) After filling the saline soil (EC: 6 dS / m) with pots, the wheat seeds soaked in step 1) were planted in the saline soil.

[0059] The growth and physiological indices of the wheat seedlings grown in saline soil for 7 days in Example 3 and Comparative Example 1 were measured, including germination rate, fresh weight, dry weight, plant height, root length, chlorophyll content, catalase content, superoxide dismutase content, peroxidase, proline content, malondialdehyde content and hydrogen peroxide content. The results are as follows: Figure 3 As shown in Table 1; the phenotypes of wheat seedlings grown for 7 days in Example 3 and Comparative Example 1 are shown in Figure 4 As shown in (a); Figure 3~4 CK represents comparative example 1, and W-Coating represents example 3.

[0060] Table 1 Growth and physiological indicators of wheat seedlings grown for 7 days in Example 3 and Comparative Example 1

[0061]

[0062] Depend on Figure 3 It can be concluded from Table 1 that under salt stress conditions, compared with Comparative Example 1, wheat seeds dipped in the fermentation liquid of Pseudomonas syringae FJ-3 can effectively improve growth indicators: germination rate ( Figure 3 Medium (a), fresh weight ( Figure 3 Middle (b)), dry weight ( Figure 3 Middle (c)), plant height ( Figure 3 middle (d)) and root length ( Figure 3 Middle (e). Physiological indicators: Chlorophyll ( Figure 3 Middle (f)), catalase ( Figure 3 Medium (g)), superoxide dismutase ( Figure 3 medium (h)), peroxidase ( Figure 3 in (i)), proline ( Figure 3 The content of (j)) in the samples increased significantly, while the content of malondialdehyde ( Figure 3 (k) content and hydrogen peroxide ( Figure 3 The content of (l)) was significantly reduced.

[0063] Combination Figure 3 and Figure 4 From (a) and Table 1, it can be concluded that seed coating with Pseudomonas aeruginosa improves the ability of wheat to cope with salt stress and is beneficial to the growth of wheat in saline soil environment.

[0064] Example 4

[0065] A flower pot filled with wheat planting substrate (peat substrate purchased from Pinstop Horticulture (Shanghai) Co., Ltd., the main component of which is peat moss) was placed in a 100 mM / L NaCl solution. NaCl moved through capillaries and was evenly distributed in the flower pot after half an hour. The conductivity EC of the potting substrate was 6 dS / m, and then the disinfected wheat seeds were sown (the disinfection and sterilization method was the same as in Example 1). The seeds were grown at 25°C (daytime) or 20°C (nighttime), with a photoperiod of 12 h and a light intensity of 240 μmol m -2 s -1 .

[0066] The bacterial suspension of Pseudomonas aeruginosa FJ-3 prepared in Example 2 was prepared into a 1% solution by volume with water as solvent, and the solution was sprayed on the leaves every two days after the wheat seedlings emerged until the liquid of the bacterial suspension no longer dripped on the leaf surface.

[0067] Sampling was carried out after 7 days of growth to measure the growth and physiological indicators of wheat.

[0068] Comparative Example 2

[0069] The method in Example 4 was used for wheat planting and foliar spraying, except that the Pseudomonas aeruginosa FJ-3 bacterial suspension in Example 4 was replaced with sterile deionized water.

[0070] The phenotypes of wheat seedlings after 7 days of growth in Example 4 and Comparative Example 2 are shown in FIG. Figure 4 As shown in (b).

[0071] The growth and physiological indices included germination rate, fresh weight, dry weight, plant height, root length, chlorophyll content, catalase content, superoxide dismutase content, peroxidase, proline content, malondialdehyde content and hydrogen peroxide content. Figure 5 As shown in Table 2, Figures 4 and 5 CK represents Comparative Example 2, and Sprinkling represents Example 4.

[0072] Table 2 Growth and physiological indicators of wheat seedlings grown for 7 days in Example 4 and Comparative Example 2

[0073]

[0074] Depend on Figure 5 From Table 2, it can be concluded that under salt stress, compared with Comparative Example 2, the wheat foliar spraying of Pseudomonas syringae FJ-3 suspension can effectively improve the growth indexes: germination rate ( Figure 5 Medium (a), fresh weight ( Figure 5 Middle (b)), dry weight ( Figure 5 Middle (c)), plant height ( Figure 5 middle (d)) and root length ( Figure 5 Middle (e). Physiological indicators: Chlorophyll ( Figure 5 Middle (f)), catalase ( Figure 5 Medium (g)), superoxide dismutase ( Figure 5 medium (h)), peroxidase ( Figure 5 in (i)), proline ( Figure 5 The content of (j)) in the samples increased significantly, while the content of malondialdehyde ( Figure 5 (k) content and hydrogen peroxide ( Figure 5 The content of (l)) was significantly reduced.

[0075] Combination Figure 4 Middle (b), Figure 5 As shown in Table 2, foliar spraying of Pseudomonas aeruginosa FJ-3 improved the ability of wheat to cope with salt stress and was beneficial to the growth of wheat in saline soil environment.

[0076] Example 5

[0077] The saline-alkali land used in this embodiment is Dongying soil, which belongs to moderate saline-alkali soil, has a sandy texture, and the basic physical and chemical properties of the 0-20 cm soil are: salt content 3.15 g / kg, pH value 8.2, organic matter 16.2 g / kg, total nitrogen 1.1 g / kg, total phosphorus 1.2 g / kg, total potassium 16.5 g / kg, available phosphorus 22.1 g / kg, and available potassium 134.4 mg / kg.

[0078] The test plants were maize ( Zea mays L.), the variety is Zhengdan 958.

[0079] The corn seeds that have been disinfected and sterilized (the disinfection and sterilization method is the same as that in Example 1) are dipped in the bacterial suspension of Pseudomonas aeruginosa FJ-3 prepared in Example 2 until the surface of the seeds is soaked to complete the coating of the bacterial suspension of Pseudomonas aeruginosa FJ-3.

[0080] Fifteen days after sowing in saline-alkali land, the emergence rate of corn was calculated, and at the harvest time, the plant height, number of ear rows, number of kernels per row, 100-kernel weight and yield of corn were calculated.

[0081] Comparative Example 3

[0082] Corn was planted under the same conditions as in Example 5, except that the Pseudomonas aeruginosa FJ-3 bacterial suspension in Example 5 was replaced with sterile water.

[0083] The results of the determination of corn germination rate, corn plant height, ear row number, row kernel number, 100-kernel weight and yield in Example 5 and Comparative Example 3 are as follows: Figure 6 As shown in Table 3, Figure 6 CK represents comparative example 3, and M-Coating represents example 5.

[0084] Table 3 Growth indicators of corn in Example 5 and Comparative Example 3 after 15 days of sowing

[0085]

[0086] From Table 3 and Figure 6 It can be concluded that compared with corn not coated with Pseudomonas aeruginosa FJ-3 suspension, the growth index of corn coated with Pseudomonas aeruginosa FJ-3 suspension was: the germination rate of corn seeds increased by 10.68% ( Figure 6 (a)); the 100-grain weight of corn seeds increased by 8.78% ( Figure 6 (e)); the yield of corn seeds increased by 8.41% ( Figure 6 Middle (f). Seed coating with suspension of Pseudomonas syringae FJ-3 in saline-alkali soil can increase seed germination rate, 100-grain weight and yield.

[0087] It can be concluded from the above embodiments that the seed coating of Pseudomonas aeruginosa FJ-3 and the foliar spraying of Pseudomonas aeruginosa FJ-3 can not only improve the seed germination rate and the growth of seedlings, but also increase the antioxidant enzymes to participate in the removal of active oxygen content in the plant body, reduce the oxidative damage to the cells, and also alleviate the problem of osmotic accumulation caused by salt stress, help cells maintain normal osmotic regulation, maintain the stability of the cell membrane, thereby improving the adaptability of plants under salt stress, and then promoting plant growth. In addition, the bacterial suspension seed coating can significantly improve the emergence rate, thereby increasing plant yield.

[0088] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A Pseudomonas syringae ( Pseudomonas hibiscicola ) FJ-3, characterized in that, The preservation number of the Pseudomonas syringae FJ-3 is CGMCC No.30327, and the preservation unit is the General Microbiology Center of China Microbiological Culture Collection Administration.

2. A bacterial agent containing the Pseudomonas aeruginosa FJ-3 according to claim 1.

3. The bacterial agent according to claim 2, characterized in that The bacterial agent includes the fermentation liquid of Pseudomonas aeruginosa FJ-3 and / or a bacterial suspension containing the Pseudomonas aeruginosa FJ-3.

4. The bacterial agent according to claim 2 or 3, characterized in that: The effective viable count of Pseudomonas aeruginosa FJ-3 in the bacterial agent is 10 7 ~10 8 CFU / mL.

5. Use of the Pseudomonas syringae FJ-3 described in claim 1 or the bacterial agent described in any one of claims 2 to 4 in one or more of improving plant salt stress tolerance, promoting plant growth and preparing seed coating agents; The plants are wheat and / or corn.

6. The use according to claim 5, characterized in that: The promoting plant growth includes one or more of increasing the germination rate of seeds, increasing the emergence rate of plants, promoting the growth of plant seedlings and increasing plant yield.

7. A method for improving plant salt stress tolerance and / or promoting plant growth, characterized in that: Includes either of the following: 1) Planting the plant seeds after coating them with the fungicide according to any one of claims 2 to 4; 2) spraying the bacterial agent according to any one of claims 2 to 4 on plant seedlings; The plants are wheat and / or corn.

8. The method according to claim 7, characterized in that The seed coating comprises: soaking the plant seeds in a fungal agent.

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