Root-promoting bacterium liquid for high and cold mining area as well as preparation method and application of root-promoting bacterium liquid

Abstract

The invention belongs to the technical field of soil remediation, and particularly relates to an alpine mining area root-promoting bacterium solution and a preparation method and application thereof. The strains in the root-promoting bacterium liquid disclosed by the invention comprise sphingomonas, arthrobacter, bacillus, motility coccus and red bacillus. Results of the embodiment of the invention show that the root system and plant height of elymus dahuricus hydroponically cultured by using the root-promoting bacterium solution are obviously increased. Furthermore, the combination of the root-promoting bacterial liquid and elymus dahuricus can significantly improve the soil components of the high and cold mining area, thereby promoting the restoration of the barren soil of the high and cold mining area.

Description

Technical Field

[0001] The present invention belongs to the field of microbial technology, and in particular relates to a root-promoting bacterial liquid for high-altitude mining areas, a preparation method thereof, and an application thereof. Background Art

[0002] The Qinghai-Tibet Plateau serves as a crucial ecological security barrier for my country, rich in mineral resources such as copper, chromium, and gold. High-altitude mining areas often face extreme conditions such as low temperatures and intense radiation. These conditions, compounded by mining-induced soil structural damage, nutrient deficiencies, and microbial suppression, severely limit the efficiency of vegetation restoration. The core challenge in current ecological restoration efforts in alpine mining areas lies in the vicious cycle between inefficient plant root regeneration and extreme environmental stress. Therefore, achieving efficient restoration in alpine mining areas requires first improving the efficiency of plant root growth in these harsh habitats.

[0003] Rhizosphere microorganisms are key mediators of plant-soil interactions and can play an important role in promoting growth, stress resistance and nutrient cycling. Remediation technologies based on single-functional strains have been widely used in low-altitude areas and have achieved good remediation effects. Patent CN119776239A uses the rhizosphere growth-promoting bacterium Paraburkholderia B24 to promote the growth of the grassland plant Leymus chinensis and enhance its drought resistance. Patent CN119570640A uses Paecilomyces lilacinus M-2 to improve the degradation efficiency of residual pesticides without affecting the insecticide's insecticide effect. However, the harsh environmental conditions in high-altitude mining areas can significantly inhibit the activity of single-functional microorganisms, resulting in the failure of remediation technology. In contrast, complex bacterial communities can systematically activate key pathways of root development through functional complementarity, such as nitrogen-fixing bacteria can provide nitrogen sources, and stress-resistant bacteria can improve the adaptability of plants to adverse environments. Patent CN109661963A enhances the growth of tea trees with root-promoting bacteria, but the application scope of this combination is declining tea gardens and lacks stress-resistant bacteria. It is not very applicable in the restoration of poor soil in high-altitude mining areas.

[0004] Based on this, there is an urgent need to develop a root-promoting bacterial solution to promote the growth of plant roots, thereby improving the poor soil composition in high-altitude mining areas. Summary of the Invention

[0005] The purpose of the present invention is to provide a root-promoting bacterial liquid for high-altitude mining areas, a preparation method and an application thereof. The root-promoting bacterial liquid provided by the present invention can promote the growth of the root system of Elymus dahliae, so that it can stably adapt to the soil environment of the high-altitude mining areas, and thus promote the repair of poor soil in the high-altitude mining areas.

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

[0007] The invention provides a root-promoting bacterial liquid, which is prepared by mixing logarithmic phase bacterial liquids of Sphingomonas, Arthrobacter, Bacillus, Moinecoccus and Rhodococcus.

[0008] Preferably, the effective live bacteria of the logarithmic phase bacterial solution of Sphingomonas, Arthrobacter, Bacillus, Moinecoccus and Rhodococcus in the root-promoting bacterial solution are all within 1×10 8 CFU / mL or above; the mixed volume ratio of the Sphingomonas, Arthrobacter, Bacillus, Moinecoccus and Rhodococcus is (1-3):(1-3):(1-2):1:1.

[0009] The present invention also provides a method for preparing a root-promoting bacterial solution, comprising inoculating the activated and rejuvenated logarithmic phase bacterial solution of Sphingomonas, Arthrobacter, Bacillus, Motile Coccus and Red Bacillus into a bacterial culture bottle containing culture medium according to a volume ratio to obtain the root-promoting bacterial solution.

[0010] Preferably, the effective viable bacteria of the logarithmic phase bacteria after activation and rejuvenation of Sphingomonas, Arthrobacter, Bacillus, Motile Coccus and Red Bacillus are all within 1×10 8 CFU / mL or above; the volume ratio of the logarithmic phase bacterial liquid of the Sphingomonas, Arthrobacter, Bacillus, Motile Coccus and Red Bacillus after activation and rejuvenation is (1-3):(1-3):(1-2):1:1.

[0011] Preferably, the total volume of the inoculated logarithmic phase bacterial solution is 1 / 6-1 / 3 of the culture medium volume.

[0012] Preferably, the components of the culture medium are: 10 g / L glucose, 5 g / L sucrose, 5 g / L peptone, 3 g / L yeast powder, 2 g / L ammonium chloride, 3 g / L potassium dihydrogen phosphate, 1.5 g / L potassium hydrogen phosphate, and 0.5 g / L magnesium sulfate.

[0013] Preferably, the culture conditions are: pH 7.0, temperature 15°C, air pressure 70 kPa, and time 48 h.

[0014] The present invention also provides the use of the root-promoting bacterial solution or the root-promoting bacterial solution prepared by the above preparation method in promoting the growth of plant roots.

[0015] The present invention also provides the use of the root-promoting bacterial solution or the root-promoting bacterial solution prepared by the above preparation method in promoting the growth of plants.

[0016] The present invention also provides the use of the root-promoting bacterial solution in combination with Elymus dahliae in repairing soil in high-altitude mining areas.

[0017] Beneficial effects of the present invention:

[0018] The present invention provides a root-promoting bacterial solution for alpine mining areas and a method for its preparation. The method has the advantages of a simple preparation process and ease of industrial production. The root-promoting bacterial solution systematically promotes plant root development through functional complementarity, maintains high activity even at low temperatures, and is adaptable to the extreme environments of alpine mining areas, thereby promoting the restoration of poor soils in these areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 This is a statistical chart showing the effects of Examples 1-5 on the root system and plant height of Elymus dahliae;

[0021] Figure 2 This is a statistical chart showing the effects of the comparative defect combination and Example 5 on the root system and plant height of Elymus dahliae. DETAILED DESCRIPTION

[0022] The present invention provides a root-promoting bacterial liquid for high-altitude mining areas. The root-promoting bacterial liquid is obtained by mixed culturing logarithmic phase bacterial liquids of Sphingomonas with a deposit number of CPCC S231596 at the China Pharmaceutical Microorganism Culture Collection Center, Arthrobacter with a deposit number of CPCC S240611 at the China Pharmaceutical Microorganism Culture Collection Center, Bacillus with a deposit number of CPCC S231278 at the China Pharmaceutical Microorganism Culture Collection Center, Planococcus with a deposit number of CPCC 101736 at the China Pharmaceutical Microorganism Culture Collection Center, and Rubrobacter with a deposit number of CPCC 203483 at the China Pharmaceutical Microorganism Culture Collection Center, according to a volume ratio of (1-3):(1-3):(1-2):1:1, preferably 3:3:2:1:1.

[0023] The method for constructing the root-promoting bacterial liquid described in the present invention is as follows: rhizosphere soil is collected from a high-altitude mining area and high-throughput sequencing is performed; the microorganisms obtained after high-throughput sequencing are analyzed to obtain information including microbial functions and sales status, and specific functional species are screened out; bacteria with root-promoting functions are cultured, activated and rejuvenated to obtain a logarithmic phase bacterial liquid of the species bacteria; the logarithmic phase bacterial liquid of the bacteria is inoculated into a conical flask filled with culture medium according to a volume ratio for culture to obtain an artificially synthesized bacterial community mother liquid.

[0024] The artificial synthetic bacterial consortium mother liquid culture medium of the present invention comprises the following components: 10 g / L glucose, 5 g / L sucrose, 5 g / L peptone, 3 g / L yeast powder, 2 g / L ammonium chloride, 3 g / L potassium dihydrogen phosphate, 1.5 g / L dipotassium hydrogen phosphate, and 0.5 g / L magnesium sulfate; the activation culture time is 7-10 days, and the rejuvenation passage number is 4 times before culture; and the volume ratio of the five types of bacteria in the logarithmic phase bacterial liquid is (1-3):(1-3):(1-2):1:1.

[0025] In the root-promoting bacterial liquid of the present invention, Sphingomonas can secrete growth hormones, Arthrobacter has the functions of solubilizing phosphate and producing cytokinins, Bacillus has the functions of fixing nitrogen and producing plant hormones, Mosella can stabilize the rhizosphere colony and enhance the disease resistance of plants, and Rhodococcus can improve the stress resistance of plants.

[0026] Elymus dahliae is a perennial herb that is drought-tolerant, cold-resistant, and saline-alkali-tolerant, with strong environmental adaptability. These characteristics give it unique advantages in ecological restoration. Its drought tolerance: Its well-developed root system allows it to penetrate deep into the soil to absorb water, helping to improve soil moisture retention. Its salt-alkali tolerance: Planting it in saline-alkali soils can effectively reduce soil salinity and improve soil structure. Its strong stress resistance: It is well-adapted to poor soils and can grow in harsh environments, thereby promoting soil improvement.

[0027] The present invention promotes the root growth of Elymus dahliae by utilizing a root-promoting bacterial solution. Because Elymus dahliae has a well-developed and dense root system, it can form a strong root network structure. This structure helps to stabilize soil particles, reduce soil erosion, and improve the soil's resistance to erosion. During the growth of Elymus dahliae's roots, the porosity of the soil can be increased, improving its air and water permeability, thereby creating better conditions for plant growth. Therefore, Elymus dahliae can significantly improve the physical structure of the soil through the action of its roots.

[0028] In the barren soil of high-altitude mining areas, the application of Elymus dahliae in combination with the root-promoting bacteria solution of the present invention can significantly increase the available nutrients, organic matter content and cation exchange capacity of the soil, thereby improving soil quality.

[0029] In order to further illustrate the present invention, the technical solution provided by the present invention is described in detail below with reference to the accompanying drawings and embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0030] The deposit number of Sphingomonas in the China Pharmaceutical Microorganism Culture Collection is CPCC S231596, the deposit number of Arthrobacter in the China Pharmaceutical Microorganism Culture Collection is CPCC S240611, the deposit number of Bacillus in the China Pharmaceutical Microorganism Culture Collection is CPCC S231278, the deposit number of Planococcus in the China Pharmaceutical Microorganism Culture Collection is CPCC 101736, and the deposit number of Rubrobacter in the China Pharmaceutical Microorganism Culture Collection is CPCC 203483. All of them are commercially available products.

[0031] Unless otherwise specified, the production processes, experimental methods or detection methods involved in the embodiments of the present invention are all conventional methods in the prior art, and their names and / or abbreviations are conventional names in the field and are very clear and unambiguous in the relevant fields of use. Those skilled in the art can understand the conventional process steps based on the names and apply the corresponding equipment to implement them according to conventional conditions or the conditions recommended by the manufacturer.

[0032] The various instruments, equipment, raw materials or reagents used in the embodiments of the present invention are not particularly limited in their sources and are all conventional products that can be purchased through regular commercial channels or prepared according to conventional methods well known to those skilled in the art.

[0033] Example 1

[0034] (1) Rhizosphere soil samples were collected in the alpine mining area and high-throughput sequencing was performed to obtain bacterial species information. Among the bacterial species with a relative abundance greater than 2%, Sphingomonas, Arthrobacter, Bacillus, Moinecoccus, and Rhodococcus were selected to construct artificial bacterial communities.

[0035] (2) The five bacteria, Sphingomonas, Arthrobacter, Bacillus, Motile Coccus and Rhodococcus, were activated and rejuvenated respectively to obtain the logarithmic bacterial solutions of the five bacteria. The effective viable bacteria in each logarithmic bacterial solution were 1×10 8 CFU / mL or above.

[0036] (3) Use a 250 mL conical flask as a bacterial culture flask, fill it with 150 mL of culture medium, and sterilize it at 121°C for 20 min. The culture medium composition is: glucose 10 g / L, sucrose 5 g / L, peptone 5 g / L, yeast powder 3 g / L, ammonium chloride 2 g / L, potassium dihydrogen phosphate 3 g / L, potassium hydrogen phosphate 1.5 g / L, and magnesium sulfate 0.5 g / L.

[0037] (4) Use a pipette to add the logarithmic phase bacterial solutions of Sphingomonas, Arthrobacter, Bacillus, Moinecoccus, and Rhodococcus into the conical flask at a volume ratio of 1:1:1:1:1, i.e., 5 mL of each bacterial strain was added.

[0038] (5) The mixed bacterial solution was cultured to simulate the environmental conditions of the high-altitude mining area. The culture conditions were set as follows: pH 7.0, simulated temperature 15°C, air pressure 70kPa, and time 48 hours.

[0039] (6) Take the cultured root-promoting bacterial solution for root-promoting test. Take Elymus dahliae seeds in the germination period (germinate in advance in the seedling tray, and take seeds with the same state for subsequent research), culture them in a hydroponic manner and observe the plant roots. The hydroponic solution components include 0.5g / L potassium nitrate, 0.6g / L calcium nitrate, 0.1g / L potassium dihydrogen phosphate, and 0.2g / L magnesium sulfate. Add 2mL / L of root-promoting bacterial solution to the hydroponic bottle, and add the same proportion of pure water to the control group. Replace the culture solution every 7 days and continue to culture for 28 days, simulating a temperature of 15℃ and an air pressure of 70kPa. Record the longest root length of the plant.

[0040] Example 2

[0041] (1) Rhizosphere soil samples were collected in the alpine mining area and high-throughput sequencing was performed to obtain bacterial species information. Among the bacterial species with a relative abundance greater than 2%, Sphingomonas, Arthrobacter, Bacillus, Moinecoccus, and Rhodococcus were selected to construct artificial bacterial communities.

[0042] (2) The five bacteria, Sphingomonas, Arthrobacter, Bacillus, Motile Coccus and Rhodococcus, were activated and rejuvenated respectively to obtain the logarithmic bacterial solutions of the five bacteria. The effective viable bacteria in each logarithmic bacterial solution were 1×10 8 CFU / mL or above.

[0043] (3) Use a 250 mL conical flask as a bacterial culture flask, fill it with 150 mL of culture medium, and sterilize it at 121°C for 20 min. The culture medium composition is: glucose 10 g / L, sucrose 5 g / L, peptone 5 g / L, yeast powder 3 g / L, ammonium chloride 2 g / L, potassium dihydrogen phosphate 3 g / L, potassium hydrogen phosphate 1.5 g / L, and magnesium sulfate 0.5 g / L.

[0044] (4) Using a pipette, add the logarithmic phase bacterial solutions of Sphingomonas, Arthrobacter, Bacillus, Moinecoccus, and Rhodococcus into a conical flask at a volume ratio of 2:1:1:1:1. The amount of Sphingomonas added was 10 mL, and the amount of the other four bacteria added was 5 mL each.

[0045] (5) The mixed bacterial solution was cultured under the following conditions: pH 7.0, simulated temperature 15°C, simulated air pressure 70 kPa, and time 48 hours.

[0046] (6) Take the cultured root-promoting bacterial solution for root-promoting test. Take Elymus dahliae seeds in the germination period (germinate in advance in the seedling tray, and take seeds with the same state for subsequent research), culture them in a hydroponic manner and observe the plant roots. The hydroponic solution components include 0.5g / L potassium nitrate, 0.6g / L calcium nitrate, 0.1g / L potassium dihydrogen phosphate, and 0.2g / L magnesium sulfate. Add 2mL / L of root-promoting bacterial solution to the hydroponic bottle. Replace the culture solution every 7 days and continue to culture for 28 days. The simulated temperature is 15℃ and the air pressure is 70kPa. Record the longest root length of the plant.

[0047] Example 3

[0048] (1) Rhizosphere soil samples were collected in the alpine mining area and high-throughput sequencing was performed to obtain bacterial species information. Among the bacterial species with a relative abundance greater than 2%, Sphingomonas, Arthrobacter, Bacillus, Moinecoccus, and Rhodococcus were selected to construct artificial bacterial communities.

[0049] (2) The five bacteria, Sphingomonas, Arthrobacter, Bacillus, Motile Coccus and Rhodococcus, were activated and rejuvenated respectively to obtain the logarithmic bacterial solutions of the five bacteria. The effective viable bacteria in each logarithmic bacterial solution were 1×10 8 CFU / mL or above.

[0050] (3) Use a 250 mL conical flask as a bacterial culture flask, fill it with 150 mL of culture medium, and sterilize it at 121°C for 20 min. The culture medium composition is: glucose 10 g / L, sucrose 5 g / L, peptone 5 g / L, yeast powder 3 g / L, ammonium chloride 2 g / L, potassium dihydrogen phosphate 3 g / L, potassium hydrogen phosphate 1.5 g / L, and magnesium sulfate 0.5 g / L.

[0051] (4) Using a pipette, add the logarithmic phase bacterial solutions of Sphingomonas, Arthrobacter, Bacillus, Moinecoccus, and Rhodococcus into a conical flask at a volume ratio of 2:2:1:1:1. The amount of Sphingomonas added was 10 mL, the amount of Arthrobacter added was 10 mL, and the amount of the other three bacteria added was 5 mL each.

[0052] (5) The mixed bacterial solution was cultured under the following conditions: pH 7.0, simulated temperature 15°C, air pressure 70 kPa, and time 48 hours.

[0053] (6) Take the cultured root-promoting bacterial solution for root-promoting test. Take Elymus dahliae seeds in the germination period (germinate in advance in the seedling tray, and take seeds with the same state for subsequent research), culture and observe the plant roots in a hydroponic manner. The hydroponic solution components include 0.5g / L potassium nitrate, 0.6g / L calcium nitrate, 0.1g / L potassium dihydrogen phosphate, and 0.2g / L magnesium sulfate. Add 2mL / L of root-promoting bacterial solution to the hydroponic bottle. Replace the culture solution every 7 days and continue to culture for 28 days. The simulated temperature is 15℃ and the simulated air pressure is 70kPa. Record the longest root length of the plant.

[0054] Example 4

[0055] (1) Rhizosphere soil samples were collected in the alpine mining area and high-throughput sequencing was performed to obtain bacterial species information. Among the bacterial species with a relative abundance greater than 2%, Sphingomonas, Arthrobacter, Bacillus, Moinecoccus, and Rhodococcus were selected to construct artificial bacterial communities.

[0056] (2) The five bacteria, Sphingomonas, Arthrobacter, Bacillus, Motile Coccus and Rhodococcus, were activated and rejuvenated respectively to obtain the logarithmic bacterial solutions of the five bacteria. The effective viable bacteria in each logarithmic bacterial solution were 1×10 8 CFU / mL or above.

[0057] (3) Use a 250 mL conical flask as a bacterial culture flask, fill it with 150 mL of culture medium, and sterilize it at 121°C for 20 min. The culture medium composition is: glucose 10 g / L, sucrose 5 g / L, peptone 5 g / L, yeast powder 3 g / L, ammonium chloride 2 g / L, potassium dihydrogen phosphate 3 g / L, potassium hydrogen phosphate 1.5 g / L, and magnesium sulfate 0.5 g / L.

[0058] (4) Use a pipette to add the logarithmic phase bacterial solutions of Sphingomonas, Arthrobacter, Bacillus, Moinecoccus, and Rhodococcus into a conical flask at a volume ratio of 2:2:2:1:1. The amount of Sphingomonas added is 10 mL, the amount of Arthrobacter added is 10 mL, the amount of Bacillus added is 10 mL, and the amount of the other two bacteria added is 5 mL each.

[0059] (5) The mixed bacterial solution was cultured under the following conditions: pH 7.0, simulated temperature 15°C, air pressure 70 kPa, and time 48 hours.

[0060] (6) Take the cultured root-promoting bacterial solution for root-promoting test. Take Elymus dahliae seeds in the germination period (germinate in advance in the seedling tray, and take seeds with the same state for subsequent research), culture them in a hydroponic manner and observe the plant roots. The hydroponic solution components include 0.5g / L potassium nitrate, 0.6g / L calcium nitrate, 0.1g / L potassium dihydrogen phosphate, and 0.2g / L magnesium sulfate. Add 2mL / L of root-promoting bacterial solution to the hydroponic bottle. Replace the culture solution every 7 days and continue to culture for 28 days. The simulated temperature is 15℃ and the air pressure is 70kPa. Record the longest root length of the plant.

[0061] Example 5

[0062] (1) Rhizosphere soil samples were collected in the alpine mining area and high-throughput sequencing was performed to obtain bacterial species information. Among the bacterial species with a relative abundance greater than 2%, Sphingomonas, Arthrobacter, Bacillus, Moinecoccus, and Rhodococcus were selected to construct artificial bacterial communities.

[0063] (2) The five bacteria, Sphingomonas, Arthrobacter, Bacillus, Motile Coccus and Rhodococcus, were activated and rejuvenated respectively to obtain the logarithmic bacterial solutions of the five bacteria. The effective viable bacteria in each logarithmic bacterial solution were 1×10 8 CFU / mL or above.

[0064] (3) Use a 250 mL conical flask as a bacterial culture flask, fill it with 150 mL of culture medium, and sterilize it at 121°C for 20 min. The culture medium composition is: glucose 10 g / L, sucrose 5 g / L, peptone 5 g / L, yeast powder 3 g / L, ammonium chloride 2 g / L, potassium dihydrogen phosphate 3 g / L, potassium hydrogen phosphate 1.5 g / L, and magnesium sulfate 0.5 g / L.

[0065] (4) Use a pipette to add the logarithmic phase bacterial solutions of Sphingomonas, Arthrobacter, Bacillus, Moinecoccus, and Rhodococcus into a conical flask at a volume ratio of 3:3:2:1:1. The amount of Sphingomonas added is 15 mL, the amount of Arthrobacter added is 15 mL, the amount of Bacillus added is 10 mL, and the amount of the other two bacteria added is 5 mL each.

[0066] (5) The mixed bacterial solution was cultured under the following conditions: pH 7.0, simulated temperature 15°C, simulated air pressure 70 kPa, and time 48 hours.

[0067] (6) Take the cultured root-promoting bacterial solution for root-promoting test. Take Elymus dahliae seeds in the germination period (germinate in advance in the seedling tray, and take seeds with the same state for subsequent research), culture and observe the plant roots in a hydroponic manner. The hydroponic solution components include 0.5g / L potassium nitrate, 0.6g / L calcium nitrate, 0.1g / L potassium dihydrogen phosphate, and 0.2g / L magnesium sulfate. Add 2mL / L of root-promoting bacterial solution to the hydroponic bottle. Replace the culture solution every 7 days and continue to culture for 28 days. The simulated temperature is 15℃ and the simulated air pressure is 70kPa. Record the longest root length of the plant.

[0068] The experimental results of Examples 1-5 are as follows Figure 1 As shown, it is shown that the root-promoting bacterial solution provided by the present invention can promote the growth of Elymus dahliae under low temperature and low pressure environments, and the longest root length and plant height are both increased.

[0069] Comparative Example

[0070] A comparative example was set based on Example 5, and the comparative example was divided into four groups. The logarithmic bacterial solution volume ratios of Sphingomonas, Arthrobacter, Bacillus, Moinecoccus, and Rhodococcus in the root-promoting bacterial solution of each group were 3:3:2:0:0, 3:3:0:1:0, 3:0:2:1:0, and 3:0:0:1:1, respectively. The specific comparative examples were set as follows:

[0071] (1) Rhizosphere soil samples were collected in the alpine mining area and high-throughput sequencing was performed to obtain bacterial species information. Among the bacterial species with a relative abundance greater than 2%, Sphingomonas, Arthrobacter, Bacillus, Moinecoccus, and Rhodococcus were selected to construct artificial bacterial communities.

[0072] (2) The five bacteria, Sphingomonas, Arthrobacter, Bacillus, Motile Coccus and Rhodococcus, were activated and rejuvenated respectively to obtain the logarithmic bacterial solutions of the five bacteria. The effective viable bacteria in each logarithmic bacterial solution were 1×10 8 CFU / mL or above.

[0073] (3) Use a 250 mL conical flask as a bacterial culture flask, fill it with 150 mL of culture medium, and sterilize it at 121°C for 20 min. The culture medium composition is: glucose 10 g / L, sucrose 5 g / L, peptone 5 g / L, yeast powder 3 g / L, ammonium chloride 2 g / L, potassium dihydrogen phosphate 3 g / L, potassium hydrogen phosphate 1.5 g / L, and magnesium sulfate 0.5 g / L.

[0074] (4) Use a pipette to add the logarithmic phase bacterial solutions of Sphingomonas, Arthrobacter, Bacillus, Moinecoccus, and Rhodococcus into a conical flask at a volume ratio of 3:3:2:0:0, 3:3:0:1:0, 3:0:2:1:0, and 3:0:0:1:1, respectively. The inoculation volume of the mixed bacterial solution is 1 / 5 of the culture medium volume, i.e., 50 mL.

[0075] (5) The mixed bacterial solution was cultured under the following conditions: pH 7.0, simulated temperature 15°C, simulated air pressure 70 kPa, and time 48 hours.

[0076] (6) Take the cultured root-promoting bacterial solution for root-promoting test. Take Elymus dahliae seeds in the germination period (germinate in advance in the seedling tray, and take seeds with the same state for subsequent research), culture and observe the plant roots in a hydroponic manner. The hydroponic solution components include 0.5g / L potassium nitrate, 0.6g / L calcium nitrate, 0.1g / L potassium dihydrogen phosphate, and 0.2g / L magnesium sulfate. Add 2mL / L of root-promoting bacterial solution to the hydroponic bottle. Replace the culture solution every 7 days and continue to culture for 28 days. The simulated temperature is 15℃ and the simulated air pressure is 70kPa. Record the longest root length of the plant.

[0077] The results are as follows Figure 2 As shown, the growth-promoting performance of the bacterial combination of the root-promoting bacterial liquid provided by the present invention decreases when some bacterial species are missing, indicating that the bacterial species combination of the root-promoting bacterial liquid provided by the present invention is functionally irreplaceable.

[0078] Although the above embodiment provides a detailed description of the present invention, 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 scope of protection of the present invention.

Claims

1. A root-promoting bacterial liquid, characterized in that The root-promoting bacterial liquid is prepared by mixing logarithmic phase bacterial liquids of Sphingomonas, Arthrobacter, Bacillus, Moinecoccus and Rhodococcus.

2. The root-promoting bacterial liquid according to claim 1, characterized in that The effective live bacteria of the logarithmic phase bacterial solution of Sphingomonas, Arthrobacter, Bacillus, Motile Coccus and Red Bacillus in the root-promoting bacterial solution are all within 1×10 8 CFU / mL or above; the mixed volume ratio of the Sphingomonas, Arthrobacter, Bacillus, Moinecoccus and Rhodococcus is (1-3):(1-3):(1-2):1:

1.

3. A method for preparing a root-promoting bacterial solution, characterized in that: The method comprises the steps of inoculating activated and rejuvenated logarithmic phase bacterial liquid of Sphingomonas, Arthrobacter, Bacillus, Motile Coccus and Red Bacillus into a bacterial culture bottle filled with culture medium according to a volume ratio to obtain a root-promoting bacterial liquid.

4. The preparation method according to claim 3, characterized in that The effective living bacteria of the logarithmic phase bacteria of Sphingomonas, Arthrobacter, Bacillus, Motile Coccus and Red Bacillus after activation and rejuvenation are all within 1×10 8 CFU / mL or above; the volume ratio of the logarithmic phase bacterial liquid of the Sphingomonas, Arthrobacter, Bacillus, Motile Coccus and Red Bacillus after activation and rejuvenation is (1-3):(1-3):(1-2):1:

1.

5. The preparation method according to claim 3, characterized in that: The total volume of the inoculated logarithmic phase bacterial solution is 1 / 6-1 / 3 of the culture medium volume.

6. The preparation method according to claim 3, characterized in that: The components of the culture medium are: 10 g / L glucose, 5 g / L sucrose, 5 g / L peptone, 3 g / L yeast powder, 2 g / L ammonium chloride, 3 g / L potassium dihydrogen phosphate, 1.5 g / L potassium hydrogen phosphate, and 0.5 g / L magnesium sulfate.

7. The preparation method according to claim 3, characterized in that: The culture conditions are as follows: pH 7.0, temperature 15° C., air pressure 70 kPa, and time 48 h.

8. Use of the root-promoting bacterial solution according to claim 1 or the root-promoting bacterial solution prepared by the preparation method according to claim 3 in promoting plant root growth.

9. Use of the root-promoting bacterial solution according to claim 1 or the root-promoting bacterial solution prepared by the preparation method according to claim 3 in promoting plant growth.

10. Use of the root-promoting bacterial solution according to claim 1 in combination with Elymus dahliae in repairing soil in alpine mining areas.

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