A kind of phosphorus-solubilizing bacteria agent and its application

Abstract

The application provides a kind of phosphorus-solubilizing bacteria of natural origin and as adsorbable carrier poultry manure, straw class exogenous organic raw materials are mixed to make phosphorus-solubilizing bacteria agent resistant to poor soil, raw material cost is low and can better improve soil microbial environment, activate soil holding nutrients, promote the nutrient absorption of plant, improve the yield and quality of plant products.

Description

Technical Field

[0001] This invention relates to the field of microbial technology, specifically to a phosphorus-solubilizing agent tolerant to poor soil and its application. Background Technology

[0002] Soil infertility and salinization are significant challenges in current agricultural production and ecological restoration. Low levels of available phosphorus in infertile soils severely impact plant growth and development. While traditional chemical fertilizers can improve soil fertility in the short term, long-term use leads to soil compaction, salinization, and environmental pollution. In recent years, environmentally friendly microbial fertilizers that activate soil nutrients and improve soil microecology have gradually become an important research direction for modern agriculture. Therefore, screening for microbial strains that can tolerate infertile and saline-alkali environments while possessing highly efficient phosphorus-solubilizing capabilities and developing related microbial agents is of great significance for soil ecological restoration and sustainable agricultural development. Summary of the Invention

[0003] The primary objective of this invention is to provide a phosphate-solubilizing agent containing microorganisms capable of tolerating barren and saline-alkali soil environments. This agent can be used for soil ecological environment restoration and forage planting.

[0004] The second objective of this invention is to provide an application of the aforementioned tolerant phosphorus-solubilizing bacteria in soil phosphorus solubilization.

[0005] The third objective of this invention is to provide an application of the aforementioned phosphate-solubilizing agent tolerant to poor soil conditions in forage cultivation.

[0006] To achieve the aforementioned first objective, this invention provides a phosphate-solubilizing bacterial agent tolerant to poor soil conditions. Its unique feature is that it comprises bacterial cells and an adsorbable carrier, wherein the adsorbable carrier is livestock or poultry manure or straw, and the bacterial cells contain phosphate-solubilizing bacteria with preservation number CGMCC No. 33382, and the phosphate-solubilizing bacteria are classified as halophilic Bacillus (Bacillus). Bacillus halotolerans The 16S rRNA sequence of phosphate-solubilizing bacteria is shown in SEQ ID No. 1.

[0007] The aforementioned phosphate-solubilizing bacteria strain was screened from the rhizosphere soil of *Leymus chinensis* in the Baiyinhua mining area of ​​Inner Mongolia. This strain is a rod-shaped, Gram-positive bacterium with smooth, moist, opaque, milky-white colonies. It is an aerobic bacterium, capable of tolerating poor and saline-alkali soil environments and possessing phosphate-solubilizing ability. This phosphate-solubilizing strain is deposited at the China General Microbiological Culture Collection Center (CGMCC), located at No. 3, Courtyard 1, Beichen West Road, Chaoyang District, Beijing, with accession number CGMCC No. 33382.

[0008] The aforementioned adsorbable carriers are selected from biomass raw materials such as poultry and livestock manure and straw, which are relatively inexpensive and readily available, and can be decomposed and utilized by phosphate-solubilizing bacteria and soil microorganisms. The inoculant obtained by mixing the adsorbable carrier with phosphate-solubilizing bacteria can effectively improve the soil microbial environment, activate soil-fixed nutrients, promote plant nutrient absorption, and increase the yield and quality of plant products. The above-mentioned phosphate-solubilizing inoculant is not limited to barren or saline-alkali soil environments; it can also be applied when soil phosphorus resources are relatively abundant and the target crop has a high phosphorus requirement.

[0009] A further proposed method is to ensure that the viable count of phosphate-solubilizing bacteria with preservation number CGMCC No. 33382 in each gram of phosphate-solubilizing bacteria tolerant to poor soil conditions is (1.0~1.5) × 10⁻¹⁰. 11 CFU.

[0010] As can be seen from the above scheme, the number of live phosphate-solubilizing bacteria per gram of phosphate-solubilizing agent that reaches the above range is beneficial to the long-term preservation of the agent, and can play a significant role in phosphate solubilization after being applied to barren soil.

[0011] To achieve the second objective mentioned above, the present invention provides an application of the aforementioned nutrient-poor soil-tolerant phosphorus-solubilizing bacteria in soil phosphorus solubilization.

[0012] A further proposed approach is to apply 10-15g of phosphate-solubilizing bacteria per kilogram of soil.

[0013] As can be seen from the above scheme, the phosphorus-solubilizing agent tolerant to poor soil can be used by applying it directly to the soil. The application rate of 10-15g per kilogram of soil can achieve a good phosphorus-solubilizing effect and the dosage is relatively economical.

[0014] To achieve the third objective mentioned above, the present invention provides an application of the aforementioned phosphate-solubilizing agent tolerant to poor soil in forage cultivation.

[0015] As can be seen from the above scheme, soils in barren and saline-alkali environments are generally not suitable for planting cash crops, so they are mainly used for animal husbandry. Forage grasses have relatively low requirements for soil fertility, so applying phosphate-solubilizing agents that are tolerant to barren soils to forage grasses is more suitable.

[0016] This invention mixes naturally sourced phosphate-solubilizing bacteria with exogenous organic raw materials such as poultry and livestock manure and straw, which serve as adsorbent carriers, to produce a phosphate-solubilizing agent tolerant to poor soil conditions. The raw material cost is low, and it can effectively improve the soil microbial environment, activate soil nutrient retention, promote plant nutrient absorption, and increase the yield and quality of plant products. Attached Figure Description

[0017] Figure 1 This is a microscopic image of the cell structure of the phosphorus-solubilizing strain tolerant to poor soil obtained in Example 1. Figure 2This is a colony morphology diagram of the phosphorus-solubilizing strains tolerant to poor soil conditions obtained in Example 1. Figure 3 This is a comparison chart of the initial viable cell counts of different dosage forms and the viable cell counts after 1 month and 3 months of storage in Example 2; Figure 4 This is a comparison chart of the available phosphorus content in the soil of the straw microbial agent treatment group, the sheep manure microbial agent treatment group, and the three control groups in Example 3; Figure 5 This is a comparison chart of soil available phosphorus conversion at 7 days and 30 days in the experimental group and blank control group with different dosages of phosphorus-solubilizing bacteria in Example 4; Figure 6 This is a comparison chart of the plant height of Leymus chinensis in Example 5 at 30d, 60d, and 90d, showing the phosphate fertilizer treatment group, the phosphate-solubilizing bacteria treatment group, and the blank control group. Detailed Implementation

[0018] The Baiyinhua mining area is located in Baiyinhua Town, in the southeastern part of Xiwuzhumuqin Banner, Xilingol League, Inner Mongolia Autonomous Region. The area has an arid and semi-arid temperate continental climate with severe soil desertification. Representative native plants include sheepgrass of the grass family.

[0019] The inventor isolated and cultured a new strain of *Bacillus subtilis* from the rhizosphere soil of *Leymus chinensis* in the Baiyinhua mining area of ​​Inner Mongolia. This strain was identified as belonging to the halophilic spore-forming bacillus group. Bacillus halotolerans This strain is a rod-shaped, Gram-positive bacterium with a smooth, moist, opaque, milky-white colony surface, and is an aerobic bacterium. This strain can tolerate poor and saline-alkali soil environments and possesses phosphorus-solubilizing ability, meaning it has the capacity to decompose insoluble phosphorus in the soil to improve the phosphorus supply to crops. Therefore, this invention refers to this strain as a phosphorus-solubilizing bacterium. The aforementioned phosphorus-solubilizing strain was deposited on January 13, 2025, at the China Microbiological Culture Collection Center (CGMCC), located at No. 3, Courtyard 1, Beichen West Road, Chaoyang District, Beijing, with accession number CGMCC No. 33382. The 16S rRNA sequence of the aforementioned phosphorus-solubilizing bacterium is shown in SEQ ID No. 1.

[0020] Example 1 This example illustrates the isolation and identification of phosphate-solubilizing strains.

[0021] Sample collection: Samples were collected from the reclaimed area of ​​Baiyinhua mining area in Inner Mongolia. Well-grown sheepgrass was selected, its root system was dug up, and the rhizosphere soil was brushed off with a brush. About 2g of rhizosphere soil was collected from each plant, and a total of 5 samples of rhizosphere soil were collected. Each sample was placed in a sterile bag and sealed. The bag was labeled with key information such as collection number, collection location, and date. The bags were placed in a thermos containing dry ice and brought back to the laboratory for storage at 4℃.

[0022] Preparation of soil microbial suspension and isolation of strains: The aforementioned collected soil sample was passed through a 100-mesh sieve. 1g of soil sample and 9mL of sterile water were added to an Erlenmeyer flask, and the flask was placed on a shaker for 30 minutes to fully disperse the microorganisms in the soil and obtain a soil suspension diluted 10 times, which was recorded as 10. -1 Diluent. Then, in the clean bench, take 1 mL of 10... -1 The diluent was placed in an Erlenmeyer flask containing 9 mL of sterile water and mixed thoroughly to obtain 10 -2 Diluent, continue to dilute and prepare 10 by the same method. -3 10 -4 Diluent.

[0023] Preparation of screening medium plates: Following the principle of reducing carbon source nutrients, a nutrient-poor inorganic phosphorus-free medium was prepared as the screening medium to simulate the barren soil conditions in mine ecological restoration. The screening medium formula was based on NBRIP medium, with the amount of glucose adjusted to 1 / 5 of the conventional amount. The specific formula was: glucose: 2g, ammonium sulfate: 0.5g, magnesium sulfate: 0.3g, manganese sulfate: 0.03g, potassium chloride: 0.3g, ferrous sulfate: 0.03g, calcium phosphate: 5g, agar: 15g, water: 1L. The components were mixed according to the above proportions, heated to dissolve, and the pH was adjusted to 7.0. After sterilization, the screening medium was obtained. The screening medium was dispensed into sterile petri dishes at a volume of 20mL per dish to prepare screening medium plates. The screening medium was used to provide a barren environment and to determine the phosphorus-solubilizing ability of the strains.

[0024] Take 1 mL of the aforementioned 10 -4 The diluted solution was evenly spread on the surface of the screening medium plate and incubated at 28°C for 48-96 hours. After isolation and purification, colonies with different morphologies and good growth were selected. After repeating the above isolation and purification process multiple times, single colonies with consistent colony characteristics were selected.

[0025] The selected single colonies were transferred to culture tubes containing screening medium with inoculation slant. These tubes were incubated at 37°C for 48 hours to obtain the selected strain, which was then stored at 4°C for later use. The selected strain was then inoculated into liquid medium and incubated at 28°C for 48 hours. The liquid medium formulation was largely the same as the screening medium, except that it did not contain agar. Subsequently, 1 mL of bacterial culture was inoculated into each 250 mL Erlenmeyer flask, and the culture was incubated at 28°C and 150 rpm for 48 hours to obtain the transplanted bacterial culture. The soluble phosphorus content in the transplanted bacterial culture was determined using the molybdenum-antimony colorimetric method.

[0026] See Figure 1In this embodiment, a phosphorus-solubilizing strain tolerant to poor soil conditions was successfully screened using the above method. This strain exhibits a rod-shaped bacterial cell and is Gram-positive under microscopic examination. See also... Figure 2 The colonies of this phosphate-solubilizing bacterium, tolerant to poor soil conditions, are milky white with wrinkled edges, opaque, and capable of producing a clear zone for phosphorus solubilization. This strain exhibited significant phosphorus-solubilizing ability in nutrient-poor inorganic phosphorus-free media, with the soluble phosphorus content in the bacterial culture (3.21 mg / L) significantly higher than the blank control group (0.37 mg / L). 16S rRNA sequencing identified this phosphate-solubilizing strain as *Bacillus halotolerans*.

[0027] Example 2 This example illustrates the impact of different formulation designs on the shelf life of phosphate-solubilizing bacteria tolerant to poor soil conditions.

[0028] This embodiment aims to compare the effects of two different formulations, wettable powder and microbial fertilizer, on the shelf life and survival rate of phosphate-solubilizing bacteria. The wettable powder formulation used kaolin, silica, and diatomaceous earth as adsorbent carriers, respectively, while the microbial fertilizer formulation used sheep manure and straw as adsorbent carriers, respectively.

[0029] Preservation experiment of wettable powder group: The screened strains in Example 1 were inoculated into LB liquid medium diluted 10 times and cultured with shaking at 30°C and 180 rpm until the late logarithmic growth stage (about 48 h). The bacterial cells were collected by centrifugation and resuspended in sterile physiological saline, and the bacterial concentration was adjusted to about 10. 12 CFU / mL was used as the inoculum suspension. For carrier mixing, 100g of sterilized kaolin, silica, and diatomaceous earth (used as adsorbent carriers) were weighed and placed in three separate mixers. 100mL of the inoculum suspension, along with 1% sodium lignosulfonate and 0.5% sodium dodecyl sulfate (based on the dry weight of the adsorbent carrier), were slowly added to each carrier. The mixture was thoroughly stirred under aseptic conditions to obtain a wet mixture. This wet mixture was then dried in a 40℃ vacuum drying oven until the moisture content was below 5%, yielding a dry mixture. The dry mixture was then pulverized using an ultrafine pulverizer and passed through a 200-mesh sieve to obtain the wettable powder product. Testing showed that the initial viable count of each powder was approximately 10. 11 CFU / g. The initial phosphate-solubilizing bacteria counts of the three wettable powders were all within the range of (1.0~1.5) × 10⁻⁶. 11 After storage at room temperature (25℃) for one month within the CFU / g range, the number of phosphate-solubilizing bacteria in all three groups of wettable powders decreased to 10. 9 CFU / g levels further decreased to 10 after 3 months. 8The CFU / g level indicates that although kaolin, silica, and diatomaceous earth can protect microorganisms to some extent, the nutrients in the carrier are insufficient to maintain microbial activity over a long period, leading to a rapid decline in microbial survival rate in the later stages of storage. Therefore, wettable powder formulations are not suitable for long-term storage and are only suitable for short-term use or scenarios requiring frequent replenishment of microorganisms.

[0030] Preservation experiment of the inoculum agent group: The inoculum suspension was prepared in the same manner as the wettable powder group. Phosphate-solubilizing inoculum was prepared using pulverized and sterilized sheep grass straw (length <1cm) and sheep manure (pH 6.5~7.0, organic matter ≥50%) as adsorbable carriers. Specifically, 100mL of the inoculum suspension was mixed with 100g of the above adsorbable carrier, dried at 35℃ until the moisture content was below 10%, and then pulverized through a 100-mesh sieve to obtain the finished inoculum agent. Testing showed that the initial viable count of both types of inoculum agents was (1.0~1.5)×10⁻¹⁰. 11 After storage at room temperature (25℃) for one month within the CFU / g range, the number of phosphate-solubilizing bacteria remained at 10. 10 The CFU / g level, after 3 months, the number of phosphate-solubilizing bacteria can still be maintained at approximately 10. 10 The CFU / g level indicates that sheep manure and straw, being rich in organic matter and nutrients necessary for microbial growth, effectively maintain microbial activity, thus demonstrating the good stability of microbial inoculant formulations. Microbial inoculant formulations have significant advantages in long-term storage, making them suitable for long-term storage and practical application, especially for soil improvement and plant growth promotion in agricultural production.

[0031] The initial viable cell counts and viable cell counts after 1 month and 3 months of storage for the above wettable powder and microbial agent are as follows: Figure 3 As shown in this example, wettable powder formulations using kaolin, silica, or diatomaceous earth as adsorbent carriers exhibit a rapid decline in microbial survival rate during the shelf life. In contrast, microbial formulations using sheep manure or hay stalks as adsorbent carriers effectively maintain microbial activity and have better long-term preservation effects. Therefore, microbial formulations have greater application potential in agriculture and ecological restoration.

[0032] Example 3 This embodiment illustrates the effects of nutrient-poor soil-tolerant phosphorus-solubilizing bacteria using poultry and livestock manure and straw as adsorbable carriers, respectively, on the available phosphorus content in the soil.

[0033] This example studies the effects of phosphate-solubilizing bacterial agents using different types of organic adsorbable carriers on the available phosphorus content in soil. Referring to Example 2, phosphate-solubilizing bacterial agents were prepared using sheep manure and sheep grass straw as adsorbent carriers, respectively. The initial number of phosphate-solubilizing bacteria in both agents was (1.0~1.5) × 10⁻⁶. 11Within the CFU / g range, the two phosphate-solubilizing agents were applied to corresponding culture pots at a ratio of 10g per kilogram of test soil. The pots were then sealed indoors without planting any plants. Corresponding adsorbable carrier controls and blank controls were also provided. The test soils were collected from reclaimed soil in the Baiyinhua mining area of ​​Inner Mongolia, air-dried, and sieved through a 2mm sieve. The basic physicochemical properties of the test soils were: pH 6.8, organic matter 12.5g / kg, total nitrogen 4.5g / kg, available potassium 105mg / kg, and available phosphorus 7.5mg / kg.

[0034] The available phosphorus content in the soil of the sheep manure microbial agent treatment group, sheep grass straw microbial agent treatment group, sheep manure control group, sheep grass straw control group, and blank control group was determined on days 7 and 30 using the sodium bicarbonate extraction-molybdenum antimony colorimetric method based on national standard HJ704-2014 (unless otherwise specified, the relevant detection methods mentioned below are the same as those mentioned here). On day 7, the available phosphorus content in the soil of the blank control group was 7.5 mg / kg, the available phosphorus content in the soil of the sheep grass straw control group was 7.6 mg / kg, the available phosphorus content in the soil of the sheep manure control group was 8.1 mg / kg, the available phosphorus content in the soil of the straw microbial agent treatment group was 11.8 mg / kg, and the available phosphorus content in the soil of the sheep manure microbial agent treatment group was the highest, reaching 15.6 mg / kg. By day 30, the available phosphorus content in the soil of the blank control group remained unchanged at 7.5 mg / kg, the available phosphorus content in the soil of the sheep grass straw control group was 7.6 mg / kg, the available phosphorus content in the soil of the sheep manure control group was 8.0 mg / kg, the available phosphorus content in the soil of the sheep grass straw inoculant treatment group was 10.4 mg / kg, and the available phosphorus content in the soil of the sheep manure inoculant treatment group was 14.3 mg / kg.

[0035] The effects of the straw microbial agent treatment group, the sheep manure microbial agent treatment group, and the three control groups on the available phosphorus content of the tested soil are as follows: Figure 4 As shown in this embodiment, sheep manure microbial inoculant has the most significant effect on increasing the available phosphorus content in the soil, followed by sheep grass straw microbial inoculant. Furthermore, the available phosphorus content in the soil of both inoculant groups was significantly higher than that of the three control groups. Sheep manure, rich in organic matter and phosphorus, can better promote the release and transformation of available phosphorus when used as an adsorbent carrier. Sheep grass straw microbial inoculant can also positively influence the transformation of available phosphorus in the soil through microbial activity and the decomposition of organic matter.

[0036] Example 4 This example illustrates the effect of different application rates of phosphate-solubilizing bacteria tolerant to poor soil conditions on the available phosphorus content in the soil.

[0037] This example studies the effect of different dosages of phosphate-solubilizing bacteria on the available phosphorus content in soil. The same test soil and *Leymus chinensis* straw bacteria agent as in Example 3 were used. The phosphate-solubilizing bacteria agent was applied to corresponding culture pots at proportions of 0 g (blank control group), 5 g, 10 g, 15 g, and 20 g per kilogram of test soil. The available phosphorus content in the soil was detected using the sodium bicarbonate extraction-molybdenum antimony colorimetric method on days 7 and 30 after application. On day 7 after application, the available phosphorus content in the soil for each group was as follows: blank control group 7.5 mg / kg, 5 g / kg phosphate-solubilizing bacteria agent treatment group 11.2 mg / kg, 10 g / kg phosphate-solubilizing bacteria agent treatment group 15.0 mg / kg, 15 g / kg phosphate-solubilizing bacteria agent treatment group 17.5 mg / kg, and 20 g / kg phosphate-solubilizing bacteria agent treatment group 18.8 mg / kg. It is evident that the available phosphorus content in all four experimental groups was significantly higher than that in the blank control group, indicating that the bacteria agent has a significant effect on activating soil phosphorus in the short term. It is worth noting that although there were differences in the available phosphorus content in the soil among the four experimental groups, statistical analysis showed that the differences among the four experimental groups were not significant, indicating that the effects of phosphate-solubilizing agents did not differ significantly in the short term within a small dosage range.

[0038] On day 30 after application, the available phosphorus content in the soil was tested again. The specific data were as follows: control group 7.5 mg / kg, 5 g / kg phosphate-solubilizing agent treatment group 9.8 mg / kg, 10 g / kg phosphate-solubilizing agent treatment group 14.5 mg / kg, 15 g / kg phosphate-solubilizing agent treatment group 15.8 mg / kg, and 20 g / kg phosphate-solubilizing agent treatment group 16.0 mg / kg. The results showed that although the available phosphorus content in the 10 g / kg, 15 g / kg, and 20 g / kg phosphate-solubilizing agent treatment groups was lower, it was still significantly higher than that in the blank control group and the 5 g / kg phosphate-solubilizing agent treatment group. Furthermore, there was no significant difference among the three experimental groups (10 g / kg, 15 g / kg, and 20 g / kg), indicating that at higher application rates, the effect of the agent tends to be stable and can maintain a high available phosphorus content in the soil for a longer period. It is worth noting that although the available phosphorus content in the 5 g / kg treatment group decreased on day 30, it was still significantly higher than that in the blank control group, indicating that even a small dose of inoculant can continuously promote the activation of soil phosphorus over a long period of time.

[0039] Figure 5 This study reflects the available phosphorus content and changes in the soil of the experimental groups and the blank control group on days 7 and 30. This example demonstrates that phosphate-solubilizing bacteria, when applied at appropriate dosages, can effectively increase the available phosphorus content in the soil and maintain its phosphorus activation effect for a relatively long period. However, excessive application may not bring significant additional benefits but instead increase costs. Considering both effectiveness and economy, an application rate of 10-15 g / kg is more suitable.

[0040] Example 5 This embodiment is used to compare the effects of phosphate-solubilizing agents tolerant to poor soil and conventional phosphate fertilizers on pasture growth.

[0041] This embodiment uses the same test soil and sheep manure inoculant as in Example 3 to grow Leymus chinensis for a comparative experiment. A 5 g / kg phosphate fertilizer treatment group, a 10 g / kg phosphate-solubilizing inoculant treatment group, and a blank control group were set up. The phosphate fertilizer treatment group used commercially available superphosphate phosphate fertilizer. All experimental groups and the blank control group were cultivated under the same single-pot planting quantity, watering amount, and light conditions. The plant height of Leymus chinensis was measured on days 30, 60, and 90. On day 90, the Leymus chinensis was harvested and the aboveground biomass was measured. On day 30, the average plant height of Leymus chinensis in the phosphate fertilizer treatment group was 38.3 cm, the average plant height in the phosphate-solubilizing inoculant treatment group was 36.2 cm, while the average plant height in the blank control group was only 28.5 cm. This indicates that after 30 days of cultivation, phosphate fertilizer had the most significant effect on promoting the growth of Leymus chinensis, followed by the phosphate-solubilizing inoculant, and the blank control group had the lowest effect.

[0042] On day 60 of cultivation, the average height of *Leymus chinensis* plants was measured. The average height in the phosphate fertilizer treatment group was 69.5 cm, in the phosphate-solubilizing agent treatment group it was 68.7 cm, and in the blank control group it was 40.1 cm. On day 90, the average height was measured again. The average height in the phosphate fertilizer treatment group was 87.5 cm, in the phosphate-solubilizing agent treatment group it was 90.4 cm, and in the blank control group it was 56.7 cm. After harvesting, the average aboveground biomass (dry weight) was 88.4 g / pot in the phosphate fertilizer treatment group, 97.1 g / pot in the phosphate-solubilizing agent treatment group, and 45.2 g / pot in the blank control group. These results indicate that phosphate-solubilizing agents and phosphate fertilizers have similar promoting effects on *Leymus chinensis* growth in the short term, both significantly improving the growth of forage plants. The blank control group, however, showed significantly limited growth due to a lack of nutrient supply. Phosphate-solubilizing bacteria can not only assist phosphate fertilizer in promoting plant growth in the short term, but also have a more significant effect on promoting the growth of forage plants over a longer period compared with conventional phosphate fertilizer, indicating that it has good potential for sustainable utilization.

[0043] Figure 5 This can reflect the plant height and changes of Leymus chinensis in the above experimental groups and blank control group at 30, 60 and 90 days. This example shows that the phosphate-solubilizing bacteria can not only assist phosphate fertilizer in promoting plant growth in the short term, but also show the same effect as phosphate fertilizer under long-term application, indicating that it has good potential for sustainable utilization.

[0044] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0045] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A phosphorus-solubilizing agent tolerant to poor soil conditions, characterized in that, The bacteria consist of bacterial cells and an adsorbable carrier, wherein the adsorbable carrier is livestock or poultry manure or straw, and the bacterial cells contain phosphate-solubilizing bacteria with preservation number CGMCC No. 33382, and the phosphate-solubilizing bacteria are classified as halophilic Bacillus (Bacillus). Bacillus halotolerans The 16S rRNA sequence of the phosphate-solubilizing bacteria is shown in SEQ ID No.

1.

2. The phosphorus-solubilizing agent tolerant to poor soil conditions as described in claim 1, characterized in that: In each gram of the aforementioned phosphate-solubilizing bacterial agent tolerant to poor soil conditions, the viable count of the phosphate-solubilizing bacteria with preservation number CGMCC No. 33382 is (1.0~1.5) × 10⁻¹⁰. 11 CFU.

3. The application of the phosphorus-solubilizing agent tolerant to poor soil as described in claim 1 or 2 in soil phosphorus solubilization.

4. The application according to claim 3, wherein, The application rate of phosphate-solubilizing bacteria tolerant to poor soil is 10-15g per kilogram of soil.

5. The application of the phosphorus-solubilizing agent for poor soil conditions as described in claim 1 or 2 in forage grass cultivation.

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