Peony acinetobacter rhizosphere and application thereof

Abstract

The invention discloses peony rhizosphere acinetobacter and application thereof, and belongs to the technical field of microorganisms. The acinetobacter strain provided by the invention has a good phosphorus-dissolving effect, and can effectively convert insoluble inorganic phosphorus into soluble inorganic phosphorus. And the strain can also be applied to a soil environment for plant growth, the utilization of phosphorus in soil is improved, the growth of plants is promoted, and the strain has important agricultural and environmental values.

Description

Technical Field

[0001] The invention belongs to the technical field of microorganisms and relates to rhizospheric Acinetobacter peonyii and applications thereof, and specifically relates to a rhizospheric Acinetobacter peonyii strain and applications of the strain in soil phosphorus solubilization and plant growth promotion. Background Art

[0002] Phosphorus is one of the macronutrients necessary for plant growth and development. Natural soil is rich in phosphorus, but due to the strong fixation and adsorption of soil minerals on phosphorus, most of the phosphorus exists in the form of insoluble phosphates such as calcium phosphate, aluminum phosphate, and iron phosphate. Therefore, more than 90% of the phosphorus in the soil is ineffective phosphorus, which limits the absorption and utilization of phosphorus nutrition by plants. Phosphate-solubilizing bacteria can convert the insoluble phosphorus in the soil into soluble phosphates that can be absorbed by plants, improve the utilization rate of phosphorus in the soil, and promote plant growth. At present, studies have found that the main phosphate-solubilizing bacteria are Luxera, Bacillus, Pseudomonas, and Klebsiella. However, there have been no reports on the research of 'Fengdan' rhizosphere strains as phosphate-solubilizing bacteria. Summary of the invention

[0003] (1) A strain of Acinetobacter sp., which was deposited in the General Microbiology Center of China National Microbiological Culture Collection Administration on December 12, 2024, with the deposit number CGMCC No.33053.

[0004] (2) A microbial agent comprising the Acinetobacter sp. described in (1).

[0005] (3) The microbial agent according to (2), wherein the content of the Lactobacillus plantarum described in (1) is not less than 10 6 cfu / mL or 10 6 cfu / g.

[0006] (4) A method for reducing the content of poorly soluble inorganic phosphorus, wherein the Acinetobacter sp. described in (1) or the microbial agent described in (2) or (3) is added to a system containing poorly soluble inorganic phosphorus.

[0007] (5) The method according to (4), wherein the poorly soluble inorganic phosphorus is converted into soluble inorganic phosphorus.

[0008] (6) The method according to (4) or (5), wherein the poorly soluble inorganic phosphorus comprises calcium phosphate, iron phosphate, or aluminum phosphate.

[0009] (7) A method for promoting plant growth, comprising adding the Acinetobacter sp. described in (1) or the microbial agent described in (2) or (3) to a system for cultivating plants.

[0010] (8) The method according to (7), wherein the promoting plant growth comprises one or more of increasing plant height, increasing plant stem circumference, and increasing plant fresh weight;

[0011] Optionally, the plants include tomato, wheat, rice, corn, cotton, rapeseed, soybean, and pea.

[0012] (9) Use of the Acinetobacter sp. described in (1) or the microbial agent described in (2) or (3) for reducing the content of sparingly soluble inorganic phosphorus.

[0013] (10) The use according to (9), wherein the poorly soluble inorganic phosphorus is converted into soluble inorganic phosphorus.

[0014] Beneficial effects: Paeonia suffruticosa rhizospheric bacteria PoPSB-1 ​​has significant soil phosphorus solubilization ability and plant growth-promoting effect, can be used to improve soil phosphorus utilization and promote plant growth, and has important agricultural and environmental value.

[0015] Biomaterial Deposit

[0016] The Acinetobacter PoPSB-1 ​​provided by the present invention is classified and named Acinetobacter sp., and has been deposited in the General Microbiology Center of the China Microbiological Culture Collection Administration on December 12, 2024, with a deposit number of CGMCC No.33053, and the deposit address is No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, Institute of Microbiology, Chinese Academy of Sciences. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is the colony morphology of strain PoPSB-1.

[0018] Figure 2 This is the phylogenetic tree of the 16S rRNA gene of strain PoPSB-1. DETAILED DESCRIPTION

[0019] In this specification, "alkaline nitrogen" refers to the form of nitrogen produced by the decomposition of organic matter in an alkaline environment. It mainly exists in soil organic matter and is one of the main forms of nitrogen in the soil. The release rate of alkaline nitrogen is slow and needs to be decomposed by microorganisms to be converted into a form that can be absorbed by plants.

[0020] In this specification, "available potassium" refers to potassium in the soil that is easily absorbed and utilized by crops, including soil solution potassium and soil exchangeable potassium. Available potassium accounts for 0.1% to 2% of the total potassium in the soil, of which soil solution potassium accounts for 1% to 2% of the available potassium. Due to its low proportion, it is often included in the exchangeable potassium. The available potassium content is one of the important indicators to characterize the soil potassium supply status.

[0021] In this specification, "available phosphorus" refers to the phosphorus components in the soil that can be absorbed by plants. It includes all water-soluble phosphorus, part of adsorbed phosphorus and organic phosphorus, and some soils also include some precipitated phosphorus.

[0022] In this specification, "organic matter" refers to substances in the soil that are derived from life, including soil microorganisms and soil animals and their secretions, as well as plant residues and plant secretions in the soil.

[0023] The present invention first screened a phosphate-solubilizing strain PoPSB-1 ​​which can convert insoluble phosphorus into soluble phosphorus from the soil where the tree peony 'Fengdan' grows, and the strain has a good conversion effect.

[0024] As a plant that needs soluble phosphorus to support its growth and development, tomatoes are highly dependent on soluble phosphorus. Soluble phosphorus is a key factor in biological processes such as photosynthesis, energy metabolism and signal transduction in tomato plants. Soluble phosphorus in the soil can be absorbed by the tomato roots and converted into phosphorus compounds required by the plants, promoting the formation and ripening of fruits. Therefore, in some exemplary embodiments, the screened phosphate-solubilizing strain PoPSB-1 ​​is added to the soil for culturing tomatoes. The results show that after adding the phosphate-solubilizing strain PoPSB-1 ​​to cultivate tomatoes, the growth state of tomatoes is better. At the same time, due to the action of the phosphate-solubilizing strain PoPSB-1, the organic matter content in the soil is also significantly improved compared with the control.

[0025] Example

[0026] The alkaline nitrogen, available potassium, available phosphorus and organic matter content in the examples were determined according to LY / T 1228-2015, NY / T889-2004, NY / T 1121.7-2014 and NY / T 1121.6-2006, respectively.

[0027] Example 1

[0028] 1.Prepare liquid and solid culture media containing insoluble inorganic phosphorus for the isolation and screening of phosphate-solubilizing bacteria.

[0029] PVF inorganic phosphorus liquid culture medium: glucose 10.0 g, ammonium sulfate 0.5 g, sodium chloride 0.3 g, magnesium sulfate heptahydrate 0.3 g, manganese sulfate 0.03 g, potassium chloride 0.3 g, ferrous sulfate heptahydrate 0.03 g, calcium phosphate 5.0 g, distilled water 1000 mL, pH 6.8-7.2, sterilization at 121°C for 20 min.

[0030] PVF inorganic phosphate solid medium: Add 15.0 g agar to PVF inorganic phosphate liquid medium.

[0031] 2. The soil bacteria suspension was spread on PVF inorganic phosphorus solid culture medium by plate spreading method, and cultured in an incubator at 30°C until colonies grew. Colonies with phosphate-solubilizing circles were selected for purification to obtain strain PoPSB-1.

[0032] 3. Determination of the phosphate solubilization ability of strain PoPSB-1

[0033] After the strain PoPSB-1 ​​was inoculated into PVF inorganic phosphorus solid medium, obvious phosphate solubilization circles appeared around the colonies after 1 to 2 days of cultivation, and these phosphate solubilization circles gradually expanded with the extension of the culture time, and basically stabilized on the seventh day. The phosphate solubilization ability of phosphate solubilizing bacteria was qualitatively analyzed by the diameter ratio (D / d) of the phosphate solubilization circle (D) and the single colony (d) on PVF inorganic phosphorus solid medium (Table 1).

[0034] Table 1

[0035] Strain name Diameter ratio (D / d) PoPSB-1 2.58±0.12

[0036] Take OD 600 =1.0, was inoculated into PVF inorganic phosphorus liquid culture medium at an inoculum size of 2% (v / v), and an equal volume of sterilized LB liquid culture medium was inoculated as a control. After constant temperature culture at 30°C for 7 days, the supernatant was collected after centrifugation, and the soluble inorganic phosphorus content in the supernatant was determined by molybdenum antimony antimicrobial spectrophotometry.

[0037] The results showed that the soluble inorganic phosphorus content in the fermentation supernatant of strain PoPSB-1 ​​reached 628.29 mg / L, while the soluble inorganic phosphorus content in the control group was less than 10 mg / L.

[0038] 4. 16S rDNA sequencing and physiological and biochemical identification of PoPSB-1 ​​strain

[0039] The efficient phosphate-solubilizing bacteria PoPSB-1 ​​strain is rod-shaped and is a Gram-negative bacterium. On inorganic phosphorus solid culture medium, its colonies are round, milky white, flat in the middle, moist on the surface, with neat and transparent edges ( Figure 1 ).

[0040] The selected strains were cultured and sent to Beijing Qingke Biotechnology Co., Ltd. for 16S rDNA sequencing. After blast comparison, the sequence similarity with the existing strains was less than 90%, indicating that it was a new strain. The 16SrRNA gene phylogenetic tree was constructed using MEGA7.0 software, and it had a high homology with some bacteria of the genus Acinetobacter ( Figure 2 ).

[0041] Refer to the Manual of Identification of Common Bacterial Systems for physiological and biochemical identification of bacteria, including catalase test, oxidase test, methyl red test, VP test, indole test, starch hydrolysis, glucose oxidation, sucrose fermentation, and gelatin liquefaction.

[0042] The results are shown in Table 2. The strain PoPSB-1 ​​was catalase positive, and the other indicators were negative.

[0043] Thus, PoPSB-1 ​​was identified as Acinetobacter.

[0044] Table 2

[0045] index PoPSB-1 index PoPSB-1 Catalase + glucose - Oxidase - sucrose - Methyl red - Starch hydrolysis - VP - Gelatin liquefaction - Indole -

[0046] Example 2

[0047] The PoPSB-1 ​​strain was inoculated into LB liquid culture medium to prepare a bacterial suspension for plant growth promotion experiments.

[0048] The selected phosphate-solubilizing bacteria PoPSB-1 ​​were inoculated into 40 mL LB liquid medium and cultured overnight at 180 r / min and 30 °C. After 18 h, the bacterial solution was collected by centrifugation, and 40 mL of sterile water was added to wash the bacteria twice. Finally, sterile water was added to adjust the bacterial solution concentration by 10 8 cfu / mL for future use.

[0049] Another strain of Bacillus subtilis WB800 (commonly used commercial phosphate-dissolving bacteria) was purchased for control, and the WB800 bacterial suspension was prepared using the same procedure.

[0050] Each pot was filled with 1.0 kg of test soil, and 30 tomato seedlings with basically the same growth were selected and planted in it. 40 mL of bacterial suspension (bacterial concentration 10 8 cfu / mL), with 40mL sterile water or 40mL WB800 bacterial suspension (bacterial concentration 10 8 cfu / mL) was used as the control. Six replicates were set for both the treatment group and the control group. The root irrigation method was used for inoculation, and the inoculation was placed in an artificial climate incubator for cultivation. After 25 days of cultivation, samples were taken to measure the growth index of tomato seedlings and the nutrient content of the soil. The results are shown in Tables 3 and 4: Tomatoes treated with strain PoPSB-1 ​​can grow better, and the organic matter content in the soil where tomatoes are cultivated is higher.

[0051] Table 3 Tomato growth indicators:

[0052] deal with Plant height (cm) Stem diameter (mm) Fresh weight of underground part (g) Fresh weight of above-ground part (g) water 20.18±1.82 4.96±0.45 3.84±0.23 5.34±0.20 PoPSB-1 23.67±1.81 5.24±0.52 4.22±0.17 6.82±0.17 WB800 22.72±2.12 4.91±0.44 3.91±0.20 6.30±0.28

[0053] Table 4 Soil nutrient content:

[0054]

[0055]

[0056] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. A strain of Acinetobacter sp. was deposited in the General Microbiology Center of China Microorganism Culture Collection Administration on December 12, 2024, with the deposit number CGMCC No.33053.

2. A microbial agent, characterized in that: Contains the Acinetobacter sp. according to claim 1.

3. The microbial agent according to claim 2, characterized in that: The content of the plant lactobacillus described in claim 1 in the microbial agent is not less than 10 6 cfu / mL or 10 6 cfu / g.

4. A method for reducing the content of sparingly soluble inorganic phosphorus, characterized in that: The Acinetobacter sp. according to claim 1 or the microbial agent according to claim 2 or 3 is added to a system containing poorly soluble inorganic phosphorus.

5. The method according to claim 4, characterized in that The poorly soluble inorganic phosphorus is converted into soluble inorganic phosphorus.

6. The method according to claim 4 or 5, characterized in that: The poorly soluble inorganic phosphorus includes calcium phosphate, iron phosphate and aluminum phosphate.

7. A method for promoting plant growth, characterized in that: The Acinetobacter sp. according to claim 1 or the microbial agent according to claim 2 or 3 is added to the plant culture system.

8. The method according to claim 7, characterized in that The promoting plant growth comprises one or more of increasing plant height, increasing plant stem circumference, and increasing plant fresh weight; Optionally, the plants include tomato, wheat, rice, corn, cotton, rapeseed, soybean, and pea.

9. Use of the Acinetobacter sp. according to claim 1 or the microbial agent according to claim 2 or 3 in reducing the content of poorly soluble inorganic phosphorus.

10. The use according to claim 9, characterized in that: The poorly soluble inorganic phosphorus is converted into soluble inorganic phosphorus.

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