Biological agent capable of improving saline-alkali soil and application of biological agent in fertilizer

Abstract

The invention discloses a biological agent capable of improving saline-alkali soil and application of the biological agent in a fertilizer. The biological agent provided by the invention comprises halophilic pseudomonas, agrobacterium, rhodovulum sulfidophilum, rhodopseudomonas palustris and bacillus velezensis. The biological agent has good salt-reducing and fertility-increasing effects, has an obvious saline-alkali soil improvement effect, and has a great practical value.

Description

Technical Field

[0001] The invention belongs to the field of saline-alkali land improvement, and particularly relates to a biological microbial agent capable of improving saline-alkali land and application of the biological agent in fertilizer. Background Art

[0002] As a widespread, low-yield soil type, saline-alkali lands, characterized by surface soil soluble salt content exceeding 0.3wt% or a pH value greater than 8.5, severely restrict crop growth and land productivity. These soils are commonly plagued by prominent issues such as sodium ion toxicity, disrupted aggregate structure, and low nutrient availability. Traditional amelioration methods to address these issues have significant limitations. For example, while salt washing methods using hydraulic engineering can reduce surface salinity in the short term, they consume a lot of water and are prone to capillary return of salt in deeper layers. Chemical amendments such as gypsum and phosphogypsum can replace sodium ions, but the high single application rates are associated with high costs and the risk of secondary pollution. Improvement with organic materials is limited by the long humification cycle and low carbon conversion efficiency.

[0003] To address these technical pain points, there is an urgent need to develop a composite microbial agent with multi-dimensional saline-alkali amelioration capabilities and significant bacterial synergy. By using strains with specific desalination properties, the improvement of saline-alkali land can be improved by orders of magnitude. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a biological agent that can improve saline-alkali land and its application in fertilizer. The biological agent can effectively reduce salt and increase fertilizer, thereby improving saline-alkali land.

[0005] To achieve this object, the present invention adopts the following technical solutions: In the first aspect, the present invention discloses a biological microbial agent, which comprises halophilic Pseudomonas, Agrobacterium, sulfur-loving red oomycetes, palustris Rhodopseudomonas, and Bacillus velez. The ratio of the number of live bacteria of halophilic Pseudomonas, Agrobacterium, sulfur-loving red oomycetes, palustris Rhodopseudomonas, and Bacillus velez is 1:(2-3):(0.5-1):(1-2):(0.7-0.9), and the total number of live bacteria of the biological microbial agent is 1×10 10 -1×10 13 CFU / g; The halophilic Pseudomonas sp. is deposited with CCTCC NO.M2013070. The Agrobacterium deposit number is GDMCC NO.64499; The deposit number of the sulfur-loving micropyle is: CCTCC NO: M2012369; The deposit number of the Rhodopseudomonas palustris is: CGMCC NO.9316; The deposit number of the Bacillus Velez is: CGMCC NO.29565.

[0006] Preferably, the biological agent includes halophilic Pseudomonas, Agrobacterium, sulfur-loving red oomycetes, palustris Rhodopseudomonas, and Bacillus Velezii. The ratio of the live bacteria count of the halophilic Pseudomonas, Agrobacterium, sulfur-loving red oomycetes, palustris Rhodopseudomonas, and Bacillus Velezii is 1: (2.5-3): (0.7-1): (1.5-2): (0.8-0.9), and the total live bacteria count of the biological agent is 1×10 12 -1×10 13 CFU / g; The halophilic Pseudomonas sp. is deposited with CCTCC NO: M2013070. The Agrobacterium deposit number is GDMCC NO.64499; The deposit number of the sulfur-loving micropyle is: CCTCC NO: M2012369; The deposit number of the Rhodopseudomonas palustris is: CGMCC NO.9316; The deposit number of the Bacillus Velez is: CGMCC NO.29565.

[0007] Further preferably, the biological agent includes halophilic Pseudomonas, Agrobacterium, sulfur-loving red oomycetes, palustris Rhodopseudomonas, and Bacillus velez. The ratio of the live bacteria count of halophilic Pseudomonas, Agrobacterium, sulfur-loving red oomycetes, palustris Rhodopseudomonas, and Bacillus velez is 1:2.5:0.7:1.5:0.8, and the total live bacteria count of the biological agent is 1×10 13 CFU / g; The halophilic Pseudomonas sp. is deposited with CCTCC NO: M2013070. The Agrobacterium deposit number is GDMCC NO.64499; The deposit number of the sulfur-loving micropyle is: CCTCC NO: M2012369; The deposit number of the Rhodopseudomonas palustris is: CGMCC NO.9316; The deposit number of the Bacillus velez is: CGMCC NO.29565.

[0008] In a second aspect, the present invention provides an application of the biological agent as described in the first aspect in preparing fertilizer; the fertilizer is either solid fertilizer or liquid fertilizer. In a third aspect, the present invention provides a fertilizer for improving saline-alkali land, the fertilizer comprising 1-50 wt% of the biological agent described in the first aspect; Preferably, the fertilizer further includes at least one of organic fertilizer, inorganic fertilizer, humic acid, and trace elements.

[0009] Preferably, the organic fertilizer includes at least one of animal bone meal, animal feces, municipal sludge, industrial organic waste, and plant residues.

[0010] Preferably, the inorganic fertilizer includes at least one of nitrogen fertilizer, phosphate fertilizer, and potassium fertilizer, wherein the nitrogen fertilizer includes at least one of ammonia water, ammonium bicarbonate, ammonium sulfate, and ammonium chloride; the phosphate fertilizer includes at least one of superphosphate, calcium magnesium phosphate, monoammonium phosphate, diammonium phosphate, and phosphate rock; and the potassium fertilizer includes at least one of potassium chloride, potassium phosphate, potassium nitrate, and potassium sulfate.

[0011] Preferably, the trace elements include inorganic salts containing at least one element selected from the group consisting of iron, boron, manganese, copper, zinc and molybdenum.

[0012] In a fourth aspect, the present invention provides a method for improving saline-alkali land, comprising the following steps: The fertilizer described in the third aspect is evenly spread in saline-alkali land with a soil pH of ≥8.5 and / or a salt content of ≥0.3% at an application rate of 5-10 kg / mu.

[0013] Compared with the prior art, the present invention has the following beneficial effects: The present invention has the following beneficial effects through the synergistic combination of specific strains: Beneficial effects

[0014] The composite microbial agent provided by the present invention is constructed through a multi-species synergistic metabolic network, demonstrating a breakthrough in saline-alkali land improvement, specifically manifested in the following multi-dimensional advantages: The five-bacteria synergistic system (halophilic Pseudomonas - Agrobacterium - Rhodopseudomonas thiophilus - Rhodopseudomonas palustris - Bacillus velez) forms a "desalination-structure stabilization-carbon fixation" cascade reaction through metabolic complementarity: Halophilic Pseudomonas aeruginosa (CCTCC M2013070) secretes halophilic polysaccharides to absorb salt ions in the soil, and combines with the nitrate reductase of Agrobacterium tumefaciens (GDMCC 64499) to synergistically reduce osmotic pressure. Rhodopseudomonas palustris (CGMCC 9316) performs photosynthesis, promoting the secretion of organic acids to regulate the pH of saline-alkali soils. Bacillus velez (CGMCC 29565) and Rhodopseudomonas thiophilus (CCTCC M2012369) form a three-dimensional "hyphae bridge-biofilm" repair system, producing lipopeptides to break down soil compaction and secreting ACC deaminase to alleviate salt stress.

[0015] Through the synergistic effect of five strains, the total salt content of saline-alkali land can be reduced while improving soil fertility, which has good market application prospects. DETAILED DESCRIPTION

[0016] The technical features of the present invention are further described below by way of specific embodiments. It should be understood by those skilled in the art that the embodiments are merely to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0017] The strains described in the present invention are specifically as follows: The halophilic Pseudomonas sp. is deposited with CCTCC NO: M2013070. The Agrobacterium deposit number is: GDMCC NO.64499; The deposit number of the sulfur-loving micropyle is: CCTCC NO: M2012369; The deposit number of the Rhodopseudomonas palustris is: CGMCC NO.9316; The deposit number of the Bacillus velez is: CGMCC NO.29565; Commercially available halophilic Pseudomonas: purchased from Ningbo Mingzhou Biotechnology Co., Ltd., product number: B65972; Commercially available Agrobacterium: purchased from Ningbo Testo Biotechnology Co., Ltd., product number: TS290635; Commercially available sulfur-loving red oomycetes: purchased from Wuhan Huizao Biotechnology Co., Ltd. Hangzhou Branch, product number: HZB149535; Commercially available Rhodopseudomonas palustris: purchased from Wuhan Huizao Biotechnology Co., Ltd. Hangzhou Branch, catalog number: HZB119728; Commercially available Bacillus velezensis was purchased from Wuhan Huizao Biotechnology Co., Ltd. Hangzhou Branch, product number: HZB507780.

[0018] Commercial fertilizer: purchased from Liaoning Sangu Agricultural Technology Co., Ltd., named organic fertilizer (for drip irrigation) (mineral source molecular carbon) Example

[0019] A biological agent capable of improving saline-alkali land, the biological agent comprises halophilic Pseudomonas, Agrobacterium, sulfur-loving red oomycetes, palustris Rhodopseudomonas, and Bacillus velez. The ratio of the number of live bacteria of the halophilic Pseudomonas, Agrobacterium, sulfur-loving red oomycetes, palustris Rhodopseudomonas, and Bacillus velez is 1:2.5:0.7:1.5:0.8, and the total number of live bacteria of the biological agent is 1×10 13 CFU / g. Example

[0020] A biological agent capable of improving saline-alkali land, the biological agent comprises halophilic Pseudomonas, Agrobacterium, sulfur-loving red oomycete, palustrine Rhodopseudomonas, and Bacillus velez. The ratio of the number of live bacteria of the halophilic Pseudomonas, Agrobacterium, sulfur-loving red oomycete, palustrine Rhodopseudomonas, and Bacillus velez is 1:3:1:2:0.9, and the total number of live bacteria of the biological agent is 1×10 12 CFU / g. Example

[0021] A biological agent capable of improving saline-alkali land, the biological agent is composed of halophilic Pseudomonas, Agrobacterium, sulfur-loving red oomycetes, palustris Rhodopseudomonas, and Bacillus Velezii, wherein the ratio of the live bacteria counts of the halophilic Pseudomonas, Agrobacterium, sulfur-loving red oomycetes, palustris Rhodopseudomonas, and Bacillus Velezii is 1:2:0.5:1:0.7, and the total live bacteria count of the biological agent is 1×10 10 CFU / g.

[0022] Comparative Example 1 The difference from Example 1 is that the biological agent only uses halophilic Pseudomonas, and the other parameters are the same as Example 1.

[0023] Comparative Example 2 The difference from Example 1 is that the biological agent only uses Agrobacterium, and the other parameters are the same as Example 1.

[0024] Comparative Example 3 The difference from Example 1 is that the biological microbial agent only uses the sulfur-loving red oomycete, and the other parameters are the same as Example 1.

[0025] Comparative Example 4 The difference from Example 1 is that the biological agent only uses Rhodopseudomonas palustris, and the other parameters are the same as Example 1.

[0026] Comparative Example 5 The difference from Example 1 is that the biological agent only uses Bacillus velezensis, and the other parameters are the same as Example 1.

[0027] Comparative Example 6 The difference from Example 1 is that commercially available halophilic Pseudomonas halophilicus CCTCC NO: M2013070 is used instead of halophilic Pseudomonas halophilicus. The other parameters are the same as those in Example 1.

[0028] Comparative Example 7 The difference from Example 1 is that commercially available Agrobacterium is used instead of Agrobacterium GDMCC NO.64499, and the other parameters are the same as Example 1.

[0029] Comparative Example 8 The difference from Example 1 is that commercially available sulfur-loving Rhodomonas aeruginosa is used to replace Rhodomonas aeruginosa CCTCC NO: M2012369, and the other parameters are the same as in Example 1.

[0030] Comparative Example 9 The difference from Example 1 is that commercially available Rhodopseudomonas palustris CGMCC NO.9316 is used instead of Rhodopseudomonas palustris CGMCC NO.9316, and the other parameters are the same as Example 1.

[0031] Comparative Example 10 The difference from Example 1 is that commercially available Bacillus velez is used instead of Bacillus velez CGMCC NO. 29565, and the other parameters are the same as Example 1.

[0032] Comparative Example 11 The difference from Example 1 is that halophilic Pseudomonas is not contained, and the missing viable bacteria count is supplemented by Agrobacterium, Rhodobacterium thiophilum, Rhodobacterium palustris, and Bacillus velezensis at a viable bacteria count ratio of 2.5:0.7:1.5:0.8. The other parameters are the same as those in Example 1.

[0033] Comparative Example 12 The difference from Example 1 is that Agrobacterium is not contained, and the missing viable bacteria count is supplemented by halophilic Pseudomonas, sulfur-loving Rhodobacterium, Rhodobacter palustris, and Bacillus velez with a viable bacteria count ratio of 1:0.7:1.5:0.8. The other parameters are the same as those in Example 1.

[0034] Comparative Example 13 The difference from Example 1 is that the sulfur-loving Rhodomonas sp. is not contained, and the missing viable bacteria count is supplemented by halophilic Pseudomonas, Agrobacterium, Rhodopseudomonas palustris, and Bacillus velezensis at a viable bacteria count ratio of 1:2.5:1.5:0.8. The other parameters are the same as those in Example 1.

[0035] Comparative Example 14 The difference from Example 1 is that Rhodopseudomonas palustris is not contained, and the missing viable bacteria count is supplemented by Halophilic Pseudomonas, Agrobacterium, Rhodopseudomonas thiophilus, and Bacillus velezensis at a viable bacteria count ratio of 1:2.5:0.7:0.8. The other parameters are the same as Example 1.

[0036] Comparative Example 15 The difference from Example 1 is that Bacillus Velezii is not contained, and the missing viable bacteria count is supplemented by halophilic Pseudomonas, Agrobacterium, Rhodobacterium sulfidophilum, and Rhodobacterium palustris at a viable bacteria count ratio of 1:2.5:0.7:1.5. The other parameters are the same as Example 1.

[0037] Comparative Example 16 The ratio of the number of live bacteria of halophilic Pseudomonas, Agrobacterium, sulfur-loving Rhodomonas, palustris, and Bacillus Velezii was 1:0.7:2.5:0.8:1.5; the number of live bacteria of the biological agent was 1×10 13 CFU / g.

[0038] Components of fertilizer and their mass percentages: Fertilizer 1: 30 wt% of biological agent (Example 1), 70 wt% of commercial fertilizer.

[0039] Fertilizer 2: biological agent (Example 2) 30wt%, commercial fertilizer 70wt%.

[0040] Fertilizer 3: biological agent (Example 3) 30wt%, commercial fertilizer 70wt%.

[0041] Fertilizer preparation method: Mix the biological agent with commercial fertilizer and stir evenly.

[0042] Test determination: Heavy metal detection: The heavy metals total cadmium, total chromium, total mercury, total lead and total arsenic were detected in Examples 1-3 and Comparative Examples 1-16 according to the standard GB 38400-2019 "Limit Requirements for Toxic and Hazardous Substances in Fertilizers".

[0043] The results show that the biological agent prepared by the present invention complies with the GB 38400-2019 standard, does not contain harmful heavy metal components, does not cause pollution to the soil and surrounding environment, and helps maintain ecological balance; it meets the requirements of sustainable agricultural development, is conducive to the recycling of resources and the long-term stability of the agricultural ecosystem.

[0044] Determination of the ability to improve saline-alkali land Experiment 1: The saline-alkali land test field was divided into 20 blocks of 1 m × 1 m, and each block was separated by a 40 cm deep and 20 cm wide ditch. The 20 blocks were plowed, and the total salt content of the 20 blocks was measured. Then, 19 of the blocks were sown with Examples 1-3 and Comparative Examples 1-16, respectively. The remaining block was kept as a blank block and was not sown; the sowing amount was 10 kg per mu. Then, the 20 blocks were plowed again and leveled. After 3 months, the total salt content of the 20 blocks was measured again.

[0045] The total salt content was tested using the residue drying-mass method; Decline rate = (measurement value before sowing - measurement value after sowing) / measurement value before sowing × 100% The organic matter improvement rate was determined using the potassium dichromate method; Organic matter improvement rate = (measurement value after sowing - measurement value before sowing) / measurement value before sowing × 100% Table 1 Results of determination of ability to improve saline-alkali land experimental group Total salt content reduction rate pH Organic matter content increase rate experimental group Total salt content reduction rate pH Organic matter content Example 1 43.27% 8.13 26.75% Comparative Example 8 30.31% 8.61 17.42% Example 2 37.65% 8.29 24.31% Comparative Example 9 32.16% 8.56 20.31% Example 3 37.33% 8.31 26.75% Comparative Example 10 24.55% 8.87 12.55% Comparative Example 1 6.62% 9.59 3.62% Comparative Example 11 29.31% 8.64 16.57% Comparative Example 2 8.31% 9.46 4.73% Comparative Example 12 20.26% 9.01 10.03% Comparative Example 3 8.55% 9.45 4.92% Comparative Example 13 21.67% 8.92 10.39% Comparative Example 4 5.72% 9.62 3.16% Comparative Example 14 34.31% 8.49 21.05% Comparative Example 5 3.38% 9.65 2.71% Comparative Example 15 12.57% 9.35 6.54% Comparative Example 6 34.52% 8.42 21.44% Comparative Example 16 28.24% 8.72 16.04% Comparative Example 7 30.64% 8.56 17.93% blank -1.42% 9.84 1.03% The results in Table 1 show that the bio-microbial agent provided by the present invention can significantly reduce the salt content in the soil, lower the soil pH value, and increase the soil organic matter content, which can effectively improve saline-alkali soil.

[0046] Comparing the results of Examples 1-3 and the blank group in Table 1, it can be seen that the biological agent provided by the present invention reduces the salt content in the soil, reduces the soil pH value, and increases the soil organic matter content.

[0047] Comparing the results of Example 1 and Comparative Examples 1-5 in Table 1, it can be seen that the effect of a single bacterial species on improving saline-alkali land is not obvious, indicating that there is a synergistic effect between the bacterial species in the biological microbial agent prepared by the present invention.

[0048] By comparing the results of Example 1 and Comparative Examples 6-10 in Table 1, it can be seen that the combination of the strains defined in the present invention has better efficacy. Although the use of commercial strains of the same species can also have a certain effect of reducing soil salinity, reducing soil pH, and increasing soil organic matter, it is less effective than the strains defined in the present invention.

[0049] Comparison of the results of Example 1 and Comparative Examples 11-15 in Table 1 shows that the bacterial species in the biological microbial agent of the present invention have a significant synergistic effect.

[0050] By comparing the results of Example 1 and Comparative Example 16 in Table 1, it can be seen that the combined use of the strains provided by the present invention has a certain effect of reducing the salt content in the soil, and the effect is particularly prominent when used at the viable bacterial count ratio specified in the present invention.

[0051] The embodiments described above are part of the embodiments of the present application, rather than all of the embodiments. The detailed description of the embodiments of the present application is not intended to limit the scope of the present application for protection, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of the present application.

Claims

1. A biological agent capable of improving saline-alkali land, characterized in that: The biological agents include halophilic Pseudomonas, Agrobacterium, sulfur-loving Rhodomonas, palustris Rhodopseudomonas, and Bacillus velez; The halophilic Pseudomonas sp. is deposited with CCTCC NO: M2013070. The Agrobacterium deposit number is: GDMCC NO.64499; The deposit number of the sulfur-loving micropyle is: CCTCC NO: M2012369; The deposit number of the Rhodopseudomonas palustris is: CGMCC NO.9316; The deposit number of the Bacillus velez is: CGMCC NO.29565.

2. The biological agent according to claim 1, characterized in that The live bacterial count ratio of the halophilic Pseudomonas, Agrobacterium, sulfur-loving Rhodomonas, palustris Rhodopseudomonas, and Bacillus Velezii is 1:(2-3):(0.5-1):(1-2):(0.7-0.9), and the total live bacterial count of the biological agent is 1×10 10 -1×10 13 CFU / g.

3. Use of the biological agent capable of improving saline-alkali land according to claim 1 or 2 in the preparation of fertilizer.

4. The application according to claim 3, characterized in that The fertilizer is liquid fertilizer or solid fertilizer.

5. A fertilizer capable of improving saline-alkali land, characterized in that: The fertilizer comprises 1-50 wt % of the biological agent according to claim 1 or 2.

6. The fertilizer according to claim 5, characterized in that The fertilizer also includes at least one of organic fertilizer, inorganic fertilizer, humic acid, and trace elements.

7. The fertilizer according to claim 6, characterized in that The organic fertilizer includes at least one of animal bone meal, animal feces, urban sludge, industrial organic waste, and plant residues.

8. The fertilizer according to claim 6, characterized in that The inorganic fertilizer includes at least one of nitrogen fertilizer, phosphate fertilizer, and potash fertilizer, wherein the nitrogen fertilizer includes at least one of ammonia water, ammonium bicarbonate, ammonium sulfate, and ammonium chloride; the phosphate fertilizer includes at least one of superphosphate, calcium magnesium phosphate, monoammonium phosphate, diammonium phosphate, and phosphate rock powder; and the potash fertilizer includes at least one of potassium chloride, potassium phosphate, potassium nitrate, and potassium sulfate.

9. The fertilizer according to claim 6, characterized in that The trace elements include inorganic salts containing at least one element among iron, boron, manganese, copper, zinc and molybdenum.

10. A method for improving saline-alkali land, characterized in that The following steps are involved: The fertilizer according to any one of claims 5 to 9 is evenly spread in saline-alkali land with a soil pH of ≥8.5 and / or a salt content of ≥0.3% at an application rate of 5-10 kg / mu.