Saline-alkali soil conditioner and preparation method thereof

Abstract

The invention discloses a saline-alkali soil conditioner and a preparation method thereof, and belongs to the technical field of soil treatment and regulation. The modifier comprises an organic adjusting component, microorganisms and fermentation products thereof, and an activity adjusting component. Organic components (physical salt control), microorganisms (biological salt reduction) and active regulation components (physiological salt resistance) form a complete salt and alkali regulation chain. After the humic acid is complexed with Na < + >, the humic acid is converted into a washable state through microbial degradation; the hydrogel of the sodium alginate delays salinity ascending and creates a microenvironment for microbial colonization; the root system expansion promoted by spermine further enhances microorganism-plant interaction, a virtuous cycle is formed, the soil desalination effect is synergistically improved, the crop growth environment is optimized, and efficient utilization of the saline-alkali soil is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of soil treatment and regulation, and particularly relates to a saline-alkali soil conditioner and a manufacturing method thereof. Background Art

[0002] Saline-alkali soil is the general term for various types of soils affected by the saline-alkali components in the soil body, including saline soil and alkaline soil. Due to the influence of the formation reasons, saline soil and alkaline soil often coexist. The salt components in saline-alkali soil are harmful salts such as sodium chloride, sodium sulfate, sodium bicarbonate and sodium carbonate, or the exchangeable sodium in the soil accounts for a certain proportion of the cation exchange capacity. Saline-alkali soil has the following characteristics: high pH value, containing harmful salts, poor air permeability, easy to harden, and low fertility. Soil salinization is a serious problem affecting agricultural production and ecological environment, and is also one of the two major soil factors restricting agricultural production increase at present. As a land resource, saline-alkali soil has great development potential. The treatment of salinization can not only improve the ecological environment of saline-alkali areas, enrich the local greening landscape pattern, provide a new habitat for biodiversity, but also better solve the problems encountered in regional environmental development and forestry economic development, and provide a broad space for realizing ecological virtuous cycle and sustainable development.

[0003] Soil improvement is a process of taking corresponding physical, biological or chemical measures against the poor texture and structure of the soil to improve the soil properties, increase the soil fertility, increase the crop yield, and improve the soil environment for human survival. Any material that is mainly used to improve the physical, chemical and biological properties of the soil to make it more suitable for plant growth, rather than mainly providing plant nutrients, is called a soil conditioner.

[0004] A soil conditioner is a preparation that can improve the soil structure and physical and chemical indexes. After being applied to the soil, it can improve the soil structure, increase the soil nutrient components and maintain the soil moisture, etc., and is more and more widely used in curbing soil degradation, improving medium and low-yield farmland, increasing capacity and storage, etc. At the same time, soil conditioners have been widely used in crop production, protective forest planting, grassland production, urban greening, highway greening and flower production, etc.

[0005] For example, Chinese Patent Application CN201810692279.2 discloses a saline-alkali soil conditioner, which is made of the following raw materials in parts by weight: 18-20 parts of plant withered leaf compost, 15-20 parts of plant straw compost, 5-10 parts of pond mud, 20-40 parts of powdered illite, 30-60 parts of granular illite, and 5-10 parts of humic acid. The soil conditioner of the present invention is prepared by respectively treating the raw materials and then mixing them evenly.

[0006] For example, Chinese Patent Application CN201510859400.2 discloses a method for improving saline-alkali soil, which mainly includes the following treatment steps: on-site investigation of the improvement plot; taking water samples; soil sample analysis; water sample analysis; design of the improvement plan; indoor leaching test: thoroughly mixing a soil bulking agent and the original soil of a chemical modifier, filling them into a soil column, and watering for the leaching test, where the addition amount of the soil bulking agent and the saline-alkali soil is 5%-20% by volume; the addition amount of the chemical modifier and the saline-alkali soil is 0.5 kg / m 2 -5 kg / m 2 ; uniformly mixing the soil bulking agent, the chemical modifier and the saline-alkali soil in proportion; setting up drainage ditches; burying drainage devices; irrigating and draining salt; measuring the physical and chemical indexes of the leaching water and the soil; The present invention provides a method for improving saline-alkali soil. Without replacing the soil, by adding a saline-alkali soil modifier, after engineering mixing and irrigating and draining salt operations, the saline-alkali soil is thoroughly improved so that it can be used for agricultural production or urban greening.

[0007] Most of the current soil modifiers focus on adding various acidic regulating substances or chemical reagents, with very limited regulation effects on the soil, weak regulation ability, single function, and poor persistence. Therefore, there is an urgent need to develop a new type of highly efficient and environmentally friendly soil conditioner to achieve the highly efficient improvement of saline-alkali soil. Summary of the Invention

[0008] In view of the problems existing in the prior art, the present invention screens a highly efficient salt- and alkali-tolerant functional microorganism, combined with an active regulating component composed of sodium alginate, spermine and brassinolide. The various raw materials interact with each other to achieve the highly efficient regulation of saline-alkali soil, improve the soil biological activity while improving the soil structure, promote the salt leaching effect, increase the kinetic parameters, reduce the soil water evaporation, and then change the salt composition, which is beneficial to the reduction of the saline-alkali obstacles in saline-alkali soil.

[0009] To achieve the above technical objectives, the technical solution adopted by the present invention is as follows: A saline-alkali soil modifier, comprising the following raw material components: an organic regulating component, a microorganism and its fermentation product, and an active regulating component.

[0010] Further, the organic regulating component comprises earthworm manure, decomposed coconut coir and humic acid, and the mass ratio of the three is (10-20):(15-23):(7-10).

[0011] Further, the microorganism and its fermentation product are obtained by mixed fermentation of the screened halophilic alkaliphilic Bacillus and the yellow curved halophilic membrane bacterium with the strain number CGMCC No. 1.16084.

[0012] Further, the halophilic alkaliphilic Bacillus ( Alkalibacillus haloalkaliphilusThe preservation number of () is CGMCC No.70240, the preservation date is June 16, 2023, and it is preserved in the China General Microbiological Culture Collection Center at No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing.

[0013] The alkaliphilic Bacillus sp. was isolated from the rhizosphere soil of rice in Sijiqing Town, Lindian County, Daqing City, Heilongjiang Province. The screening method is as follows: Take 10 g of rhizosphere soil of rice and add it to a conical flask containing 90 mL of sterile water. After shaking on a shaker at 30 °C and 160 r / min for 30 min, it is diluted successively from 10 -1 to 10 -7 , take 10 -5 , 10 -6 , 10 -7 gradient soil suspensions of 100 μL are respectively spread on LB medium plates. Three replicate experiments are set for each gradient. After inverted culture in a constant temperature incubator at 30 °C for 2-4 d, strains with different colony morphologies are selected for isolation and purification. After obtaining single colonies, they are stored in a 4 °C refrigerator for later use.

[0014] The salt tolerance and alkali tolerance of the obtained strains were measured. The strains were inoculated into LB liquid media containing 0.1-1.7 mol / L NaCl, 100, 150, 200, 250, 300 mmol / L soda salts and pH 3.0-11.0 at an inoculation amount of 1%. After shaking culture at 25-35 °C and 160 r / min for 24 h, the optical density value (OD 600 ) was measured, and the experiment was repeated 3 times. Finally, a strain showing the highest tolerance at different salt concentrations and pH values was screened, which is the alkaliphilic Bacillus sp. After streaking this strain on LB medium, it was found that the colony morphology of the strain was round, white and transparent, the colony edge was relatively neat, easy to pick up, and the colony morphology was as Figure 1 shown.

[0015] Furthermore, the preservation number of the Curvibacter salinus ( Flaviflexus salsibiostraticola ) is CGMCC No.1.16084, the original preservation date is January 15, 2017, and it is preserved in the China General Microbiological Culture Collection Center. This strain can be purchased openly through the preservation center without secondary preservation.

[0016] Further, the active regulatory component is composed of sodium alginate, spermine and brassinolide mixed in a mass ratio of 1:1:1.

[0017] A method for manufacturing a saline-alkali soil conditioner includes the following preparation steps: (1) Preparation of organic regulatory components: Mix the raw material coco coir and microbial inoculum at a mass ratio of 1:0.05, adjust the water content to 60%-65%, conduct composting fermentation for 24-26 days at a temperature of 55-65°C, turn the pile once every 3 days, and after maturity, the pH drops to 7.2-7.5 and the C / N ratio stabilizes at 22-24 to obtain matured coco coir; crush vermicompost and matured coco coir to a particle size of ≤2 mm respectively, and mix them evenly according to the mass ratio of vermicompost, matured coco coir and humic acid of (10-20):(15-23):(7-10), adjust the water content of the mixed material to 30%-35%, and let it stand for aging for 5 days to enhance the binding force to obtain the organic regulating component; (2) Preparation of microorganisms and their fermentation products: Inoculate Bacillus halophilus alkaliphilus into the activation medium A, and culture it in a shaker at 28-30°C and a rotation speed of 150-200 rpm for 48 hours to obtain the activated bacterial liquid of Bacillus halophilus alkaliphilus; inoculate Flexibacter flavus halophilus into the activation medium B, and culture it in a shaker at 28-30°C and a rotation speed of 120-150 rpm for 48 hours to obtain the activated bacterial liquid of Flexibacter flavus halophilus; mix the two bacterial liquids according to a volume ratio of 2:1, and then inoculate them into the fermentation carrier according to 8% of the mass of the fermentation carrier, adjust the water content to 50%-55% and the pH to 8.5-9.0, and conduct fermentation culture for 70-90 hours, turning the material once every 8 hours to ensure uniform distribution of the bacterial cells; after fermentation is completed, use vacuum freeze-drying to retain the bacterial cell activity and metabolites; finally, ultra-finely crush it to a particle size of ≤0.1 mm and pass through a 200-mesh sieve to obtain a grayish-white powdery mixture, which is the microorganisms and their fermentation products; (3) Preparation of the modifier: Mix the organic regulating component, the microorganisms and their fermentation products, and the active regulating component evenly according to a mass ratio of 20:3:1, granulate them using a twin-screw extrusion granulator with a die hole diameter of 3-5 mm, and dry the particles until the water content is ≤8% to obtain the final product.

[0018] Furthermore, in step (1), the microbial inoculum is EM bacteria and Bacillus subtilis, and the mass ratio between them is 5:3.

[0019] Furthermore, by mass percentage: in step (2), the composition of the activation medium A is: peptone 1%, yeast extract 0.5%, NaCl 8%, the balance is water, and the pH is 8.5-9.0; the composition of the medium B is: glucose 2%, peptone 1%, NaCl 5%, MgSO4 0.1%, the balance is water, and the pH is 8.5; the composition of the fermentation carrier is: corncob powder 60%, soybean meal powder 30%, diatomaceous earth 10%, adjust the water content to 50%-55% and the pH to 8.5-9.0.

[0020] All raw material substances used in the present invention are commercially available.

[0021] Dosage and usage: Light saline-alkali land (EC < 4 mS / cm, pH < 8.5): 100 - 150 kg / mu.

[0022] Medium saline-alkali land (EC 4 - 8 mS / cm, pH 8.5 - 9.0): 150 - 200 kg / mu.

[0023] Heavy saline-alkali land (EC > 8 mS / cm, pH > 9.0): 200 - 250 kg / mu. Spread the modifier evenly on the field surface, and incorporate it into the 20 - 30 cm soil layer by rotary tillage to ensure full mixing with the soil. After application, irrigate the field and soak it for 5 - 7 days to promote salt leaching and microbial colonization. Apply continuously for 2 years, 1 - 2 times a year, and the saline-alkali land can be gradually transformed into a high-yield field.

[0024] Beneficial effects: (1) The halophilic alkaliphilic Bacillus screened in the present invention can first tolerate high saline-alkali environments. Secondly, bioactive substances secreted by the strain, such as exopolysaccharides (EPS), can form biofilms in the soil to wrap salt crystals and inhibit salt precipitation; at the same time, enzymes such as alkaline phosphatase and urease are produced to promote the activation of insoluble phosphorus and potassium. The metabolites of Flexistipes sinusarabici, such as organic small molecules like γ-aminobutyric acid (GABA) and proline, reduce the osmotic potential of plant cells, activate the expression of plant salt-tolerant genes, enhance the ability of cells to regionalize and isolate Na⁺, and improve the salt and alkali resistance of crops.

[0025] (2) Earthworm manure and decomposed coconut coir are rich in humus and colloidal substances, which can significantly increase the soil organic matter content. Through the physical adsorption and bridging action of colloidal particles, it promotes the formation of soil aggregate structures, reduces soil bulk density, increases porosity, and enhances water permeability and air permeability; the carboxyl, phenolic hydroxyl and other active groups of humic acid can undergo ion exchange or complexation reactions with Na in saline-alkali soil + to form stable humic acid-sodium complexes, effectively reducing the toxicity of sodium ions to plant roots, and at the same time promoting the leaching of salt ions with water infiltration. At the same time, the lignocellulose degradation products (such as reducing sugars) of decomposed coconut coir provide long-term nutrition for microorganisms and maintain the activity of the microbial community.

[0026] (3) Active regulatory components play a role in enhancing crop resistance on the one hand and can regulate microbial activity on the other hand. The β-1,4-mannuronic acid chain of sodium alginate can form a three-dimensional network hydrogel in the soil, locking up moisture and reducing the surface accumulation of salts caused by evaporation; its oligosaccharide fragments can be used as signal molecules to induce an increase in the activities of antioxidant enzymes such as superoxide dismutase (SOD) and peroxidase (POD) in plants, enhancing the plant's resistance to oxidative stress and further alleviating the stress effect of the saline-alkali environment on crops. Spermine, as a polyamine substance, can promote the synthesis of cytokinins (such as ZR), stimulate the proliferation of root meristems, and at the same time inhibit the activity of ACC oxidase in the ethylene production pathway, delaying senescence induced by salt stress; and brassinosteroids are not only a good plant hormone. Brassinosteroids can bind to regulatory proteins such as TypA and Lrp in microorganisms, inducing the synthesis of salt-tolerant related enzymes (such as urease and glutamine synthetase) and secondary metabolites (such as antibiotic substances), enhancing the advantages of strains in a competitive environment and ensuring their continuous and effective regulatory role.

[0027] (4) In summary, the organic components (physical salt control), microorganisms (biological salt reduction), and active components (physiological salt resistance) form a complete saline-alkali regulation chain. For example: After humic acid chelates Na + it is degraded and transformed into a leachable state by microorganisms; the hydrogel of sodium alginate delays the upward movement of salts, creating a microenvironment for microbial colonization; the root expansion promoted by spermine further enhances the microbe-plant interaction, forming a virtuous cycle, synergistically improving the soil desalination effect, optimizing the crop growth environment, and realizing the efficient utilization of saline-alkali land. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is the colony morphology diagram of the halophilic alkaliphilic Bacillus of the present invention; Figure 2 It is the experimental diagram of the rice planting yield in the examples and comparative examples. DETAILED DESCRIPTION OF THE INVENTION

[0029] The technical solutions of the present invention will be further described below in conjunction with specific embodiments, but are not limited thereto.

[0030] Example 1 A saline-alkali soil conditioner contains the following raw material components: organic regulatory components, microorganisms and their fermentation products, and active regulatory components.

[0031] The organic regulatory components include earthworm manure, decomposed coconut coir, and humic acid, and the mass ratio of the three is 20:15:7.

[0032] The microorganisms and their fermentation products are obtained by mixed fermentation of the screened halophilic alkaliphilic Bacillus and the yellow curved halophilic membrane bacterium with the strain number CGMCC No. 1.16084.

[0033] Furthermore, the preservation number of the alkaliphilic Bacillus is CGMCC No. 70240, the preservation date is June 16, 2023, and it is preserved in the China General Microbiological Culture Collection Center at No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing.

[0034] The alkaliphilic Bacillus was isolated from the rhizosphere soil of rice in Lin Dian Sijiqing Town, Daqing City, Heilongjiang Province. The screening method is as follows: Take 10 g of rhizosphere soil of rice and add it to a conical flask containing 90 mL of sterile water. After shaking at 30 °C and 160 r / min for 30 min, dilute it successively from 10 -1 to 10 -7 Take 10 -5 , 10 -6 , 10 -7 Gradient soil suspensions of 100 μL were respectively spread on LB medium plates. Three replicate experiments were set for each gradient. After inverted culture in a constant temperature incubator at 30 °C for 2 - 4 d, strains with different colony morphologies were selected for isolation and purification. After obtaining single colonies, they were stored in a refrigerator at 4 °C for standby.

[0035] The salt tolerance and alkali tolerance of the obtained strains were determined. The strains were inoculated into LB liquid media containing 0.1 - 1.7 mol / L NaCl, 100, 150, 200, 250, 300 mmol / L soda salts, and pH 3.0 - 11.0 at an inoculation amount of 1%. After shaking culture at 25 - 35 °C and 160 r / min for 24 h, the optical absorption value (OD 600 ) was measured, and this was repeated 3 times. Finally, a strain showing the highest tolerance at different salt concentrations and pH values was screened out, which is the alkaliphilic Bacillus. After streaking this strain on the LB medium, it was found that the colony morphology of the strain was round, white and transparent, the colony edge was relatively neat, and it was easy to pick up. The colony morphology is as Figure 1 shown.

[0036] The preservation number of the yellow curved bacterium living in salt film is CGMCC No. 1.16084, the original preservation date is January 15, 2017, and it is preserved in the China General Microbiological Culture Collection Center. This strain can be purchased openly through the preservation center without the need for secondary preservation.

[0037] The active regulatory component is composed of sodium alginate, spermine, and brassinolide mixed in a mass ratio of 1:1:1.

[0038] A method for manufacturing a saline-alkali soil conditioner includes the following preparation steps: (1) Preparation of the organic regulatory component: Mix the raw material coco coir with the microbial inoculant at a mass ratio of 1:0.05, adjust the water content to 60%-65%, conduct composting fermentation for 24-26 days at a temperature of 55-65°C, with a turning frequency of once every 3 days. After compost maturity, the pH drops to 7.2-7.5 and the C / N ratio stabilizes at 22-24 to obtain matured coco coir; separately crush vermicompost and matured coco coir to a particle size of ≤2 mm, and mix them evenly according to the mass ratio of vermicompost, matured coco coir, and humic acid of 20:15:7. Adjust the water content of the mixed materials to 30%-35%, and let it stand and age for 5 days to enhance the binding force to obtain the organic regulating component; (2) Preparation of microorganisms and their fermentation products: Inoculate Bacillus halophilus alkaliphilus into the activation medium A, and culture it on a shaker at 28-30°C and a rotation speed of 150 - 200 rpm for 48 hours to obtain the activated bacterial liquid of Bacillus halophilus alkaliphilus; inoculate Flexibacter flavus halophilus into the activation medium B, and culture it on a shaker at 28-30°C and a rotation speed of 120-150 rpm for 48 hours to obtain the activated bacterial liquid of Flexibacter flavus halophilus; after mixing the two bacterial liquids according to a volume ratio of 2:1, inoculate them into the fermentation carrier at 8% of the mass of the fermentation carrier, adjust the water content to 50%-55%, pH 8.5-9.0, and conduct fermentation culture for 70 hours, turning the materials once every 8 hours to ensure uniform distribution of the bacteria; after fermentation is completed, use vacuum freeze-drying to retain the bacterial activity and metabolites; finally, ultrafinely crush to a particle size of ≤0.1 mm and pass through a 200-mesh sieve to obtain a grayish-white powdery mixture, which is the microorganisms and their fermentation products; (3) Preparation of the modifier: Mix the organic regulating component, microorganisms and their fermentation products, and the active regulating component evenly according to a mass ratio of 20:3:1, and granulate them using a twin-screw extrusion granulator with a die hole diameter of 3-5 mm. Dry the granules until the water content is ≤8% to obtain the final product.

[0039] Among them, in step (1), the microbial inoculant is EM bacteria and Bacillus subtilis, and their mass ratio is 5:3.

[0040] According to the mass percentage: Among them, the composition of the activation medium A in step (2) is: peptone 1%, yeast extract 0.5%, NaCl 8%, and the balance is water, pH 8.5-9.0; the composition of the medium B is: glucose 2%, peptone 1%, NaCl 5%, MgSO4 0.1%, and the balance is water, pH 8.5; the composition of the fermentation carrier is: corncob powder 60%, soybean meal powder 30%, diatomaceous earth 10%, adjust the water content to 50%-55%, pH 8.5-9.0.

[0041] Example 2 A saline-alkali soil modifier contains the following raw material components: organic regulating component, microorganisms and their fermentation products, and active regulating component.

[0042] The organic regulating component comprises earthworm castings, coconut bran decomposed matter and humic acid, and the mass ratio of the three is 20:23:10.

[0043] The microorganism and the fermentation product thereof are obtained by mixed fermentation of the screened halophilic alkaline bacillus and the salt-film yellow Campylobacter with a strain number of CGMCC No. 1.16084.

[0044] The preservation number of the halophilic alkaline Bacillus is CGMCC No.70240, the preservation date is June 16, 2023, and it is deposited in the General Microbiology Center of the China Culture Collection Administration, with the address at No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing.

[0045] The separation and screening method of the halophilic alkaline Bacillus is the same as that in Example 1.

[0046] The salt membrane yellow Campylobacter is the same as that in Example 1.

[0047] The active regulating component is prepared by mixing sodium alginate, spermine and brassinosteroid in a mass ratio of 1:1:1.

[0048] A method for preparing a saline-alkali soil conditioner comprises the following preparation steps: (1) Preparation of organic regulating components: The raw material coconut bran is mixed with the microbial agent in a mass ratio of 1:0.05, the moisture content is adjusted to 60%-65%, the compost is fermented for 24-26 days at a temperature of 55-65°C, the compost is turned every 3 days, the pH value is reduced to 7.2-7.5 after decomposition, and the C / N ratio is stabilized at 22-24 to obtain the coconut bran decomposed material; the earthworm manure and the coconut bran decomposed material are respectively crushed to a particle size of ≤2mm, the earthworm manure, the coconut bran decomposed material and the humic acid are mixed evenly in a mass ratio of 20:23:10, the moisture content of the mixed material is adjusted to 30%-35%, and the mixed material is aged for 5 days to enhance the binding force to obtain the organic regulating component; (2) Preparation of microorganisms and their fermentation products: Inoculate Bacillus halophilus in activation medium A, and culture it in a shaker at 28 - 30°C and a rotation speed of 150 - 200 rpm for 48 hours to obtain an activated bacterial solution of Bacillus halophilus; inoculate Campylobacter lari in activation medium B, and culture it in a shaker at 28 - 30°C and a rotation speed of 120 - 150 rpm for 48 hours to obtain an activated bacterial solution of Campylobacter lari; mix the two bacterial solutions according to a volume ratio of 2:1, inoculate them into a fermentation carrier at 8% of the mass of the fermentation carrier, adjust the water content to 50% - 55%, pH 8.5 - 9.0, and carry out fermentation culture for 90 hours, turning the materials once every 8 hours to ensure uniform distribution of the bacterial bodies; after fermentation is completed, carry out vacuum freeze-drying to retain the activity of the bacterial bodies and metabolites; finally, ultrafinely pulverize to a particle size of ≤0.1 mm, and pass through a 200-mesh sieve to obtain a grayish-white powdery mixture, which is the microorganism and its fermentation product; (3) Preparation of the modifier: Mix the organic regulating component, the microorganism and its fermentation product, and the activity regulating component evenly according to a mass ratio of 20:3:1, granulate using a twin-screw extrusion granulator, with a die hole diameter of 3 - 5 mm, and dry the particles to a water content of ≤8% to obtain the final product.

[0049] Among them, in step (1), the microbial inoculum is EM bacteria and Bacillus subtilis, and their mass ratio is 5:3.

[0050] According to the mass percentage: Among them, the composition of activation medium A in step (2) is: peptone 1%, yeast extract 0.5%, NaCl 8%, and the balance is water, pH 8.5 - 9.0; the composition of medium B is: glucose 2%, peptone 1%, NaCl 5%, MgSO4 0.1%, and the balance is water, pH 8.5; the composition of the fermentation carrier is: corncob powder 60%, soybean meal powder 30%, diatomaceous earth 10%, adjust the water content to 50% - 55%, pH 8.5 - 9.0.

[0051] Comparative Example 1 In this comparative example, except that only Campylobacter lari was used in total in the microorganism and its fermentation product, the other raw materials and process steps were the same as in Example 1.

[0052] A saline-alkali soil modifier contains the following raw material components: an organic regulating component, a microorganism and its fermentation product, and an activity regulating component.

[0053] The organic regulating component includes earthworm manure, decomposed coconut coir, and humic acid, and their mass ratio is 20:15:7.

[0054] The microorganism and its fermentation product are obtained by fermenting Campylobacter lari with the strain number CGMCC No. 1.16084.

[0055] The preservation number of the described Vibrio flavus halophilus is CGMCC No. 1.16084, and the original preservation date is January 15, 2017. It is preserved in the General Microbiology Center of the China National Center for Culture Collection of Microorganisms. This strain can be purchased through the open purchase of the preservation center without secondary preservation.

[0056] The described active regulatory component is composed of sodium alginate, spermine, and brassinolide mixed in a mass ratio of 1:1:1.

[0057] A method for manufacturing a saline-alkali soil conditioner includes the following preparation steps: (1) Preparation of the organic regulatory component: Mix the raw material coconut coir with the microbial inoculant in a mass ratio of 1:0.05, adjust the water content to 60%-65%, and perform composting fermentation for 24-26 days at a temperature of 55-65°C, with a turning frequency of once every 3 days. After composting, the pH drops to 7.2-7.5, and the C / N ratio stabilizes at 22-24 to obtain the decomposed coconut coir; crush the earthworm manure and the decomposed coconut coir to a particle size of ≤2 mm respectively, and mix them evenly according to the mass ratio of earthworm manure, decomposed coconut coir, and humic acid of 20:15:7. Adjust the water content of the mixed material to 30%-35%, and let it stand for aging for 5 days to enhance the binding force to obtain the organic regulatory component; (2) Preparation of microorganisms and their fermentation products: Inoculate Vibrio flavus halophilus into the activated medium B, and culture it in a shaker at 28-30°C and a rotation speed of 120-150 rpm for 48 hours to obtain the activated bacterial liquid of Vibrio flavus halophilus; inoculate the activated bacterial liquid into the fermentation carrier at 8% of the mass of the fermentation carrier, adjust the water content to 50%-55%, pH 8.5-9.0, and perform fermentation culture for 70 hours, turning the material once every 8 hours to ensure uniform distribution of the bacterial cells; after fermentation, use vacuum freeze-drying to retain the bacterial cell activity and metabolites; finally, ultra-finely crush it to a particle size of ≤0.1 mm and pass through a 200-mesh sieve to obtain a grayish-white powdery mixture, which is the microorganisms and their fermentation products; (3) Preparation of the conditioner: Mix the organic regulatory component, the microorganisms and their fermentation products, and the active regulatory component evenly in a mass ratio of 20:3:1, and granulate them using a twin-screw extrusion granulator with a die hole diameter of 3-5 mm. The granules are dried to a water content of ≤8% to obtain the final product.

[0058] Comparative Example 2 In this comparative example, except that only Bacillus alkalophilus halophilus is used in total in the microorganisms and their fermentation products, the other raw materials and process steps are the same as those in Example 1.

[0059] A saline-alkali soil conditioner contains the following raw material components: an organic regulatory component, microorganisms and their fermentation products, and an active regulatory component.

[0060] The organic regulating component comprises earthworm castings, coconut bran decomposed matter and humic acid, and the mass ratio of the three is 20:15:7.

[0061] The microorganism and the fermented product thereof are obtained by fermenting the screened halophilic alkaline bacillus.

[0062] The preservation number of the halophilic alkaline Bacillus is CGMCC No.70240, the preservation date is June 16, 2023, and it is deposited in the General Microbiology Center of the China Culture Collection Administration, with the address at No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing.

[0063] The separation and screening method of the halophilic alkaline Bacillus is the same as that in Example 1.

[0064] A method for preparing a saline-alkali soil conditioner comprises the following preparation steps: (1) Preparation of organic regulating components: The raw material coconut bran is mixed with the microbial agent in a mass ratio of 1:0.05, the moisture content is adjusted to 60%-65%, the compost is fermented for 24-26 days at a temperature of 55-65°C, the compost is turned every 3 days, the pH value is reduced to 7.2-7.5 after decomposition, and the C / N ratio is stabilized at 22-24 to obtain the coconut bran decomposed material; the earthworm manure and the coconut bran decomposed material are respectively crushed to a particle size of ≤2mm, and the earthworm manure, the coconut bran decomposed material and the humic acid are mixed uniformly in a mass ratio of 20:15:7, the moisture content of the mixed material is adjusted to 30%-35%, and the mixed material is aged for 5 days to enhance the binding force to obtain the organic regulating component; (2) Preparation of microorganisms and their fermentation products: The halophilic alkaline Bacillus was inoculated into an activation medium A, and cultured in a shaking table at 28-30° C. and a rotation speed of 150-200 rpm for 48 hours to obtain an activated bacterial solution of the halophilic alkaline Bacillus; the bacterial solution was inoculated into a fermentation carrier according to 8% of the mass of the fermentation carrier, and the water content was adjusted to 50%-55%, and the pH value was 8.5-9.0, and fermentation culture was carried out for 70 hours, and the material was turned over every 8 hours to ensure that the bacteria were evenly distributed; after the fermentation was completed, vacuum freeze drying was performed to retain the activity of the bacteria and metabolites; finally, ultrafine grinding was performed to a particle size of ≤0.1 mm, and a 200-mesh sieve was passed to obtain an off-white powder mixture, which was the microorganism and its fermentation product; (3) Preparation of improver: The organic regulating component, microorganism and its fermentation product and active regulating ingredient are mixed uniformly in a mass ratio of 20:3:1, and granulated by a twin-screw extruder granulator with a die hole diameter of 3-5 mm. The granules are dried to a moisture content of ≤8% to obtain the final product.

[0065] Comparative Example 3 In this comparative example, except that spermine is not used in the activity regulating component, the other raw materials and process steps are the same as those in Example 1.

[0066] The active regulating component is composed of sodium alginate and brassinosterol mixed in a mass ratio of 1:1.

[0067] Comparative Example 4 In this comparative example, except for not using brassinosterol in the active regulating component, the other raw materials and process steps are the same as those in Example 1.

[0068] The active regulating component is composed of sodium alginate and spermine mixed in a mass ratio of 1:1.

[0069] Comparative Example 5 In this comparative example, except for not using spermine and brassinosterol in the active regulating component, the other raw materials and process steps are the same as those in Example 1.

[0070] The active regulating component is sodium alginate.

[0071] Experimental test Determination of the salt tolerance ability of the strains: Inoculate Bacillus halophilus and Flexibacter flavus halophilus into LB liquid medium respectively, and culture at 30 °C and 180 r / min until the OD600 value reaches 0.6 - 0.8. Streak-culture the bacterial liquid on LB solid medium with the medium pH value of 9.0, NaCl concentrations of 0, 20, 40, 60, 80, 100, 120, 140, 160, 180 and 200 g / L respectively, and without adjusting the pH, and the salt concentration of 0 g / L [abbreviated as 0(-)]. Incubate the culture in an inverted position in a constant temperature incubator at 30 °C. Count the colony diameter size of the strains every 24 h, repeat the measurement 3 times at each time point, and take the average value.

[0072] Table 1 Salt tolerance ability of Bacillus halophilus and Flexibacter flavus halophilus Note: -: No growth; +: Growth and colony diameter < 0.3 mm; ++: Colony diameter 0.3 - 0.5 mm; +++: Colony diameter 0.5 - 0.8 mm; ++++: Colony diameter > 0.8 mm.

[0073] At pH 9.0, the strains can grow on LB plates with NaCl concentrations of 0 - 180 g / L. When the NaCl concentration is 60 - 140 g / L, the growth is the best, and both strains have good salt tolerance performance.

[0074] Determination of the alkali reduction ability of the strains: Inoculate OD respectively in LB liquid medium with pH 8.0 - 10.0 600The bacterial solutions of Bacillus halophilus and Flexibacter flavus halophilus with values of 0.6 - 0.8 were cultured at 30 °C and 180 r / min for 4 d. Every 12 h, 0.5 mL of the bacterial solution was taken and centrifuged at 4000 r / min for 5 min. The supernatant was taken and the pH value of the bacterial solution was measured with a pH meter. The alkali reduction rate was calculated according to formula (1): η alkali(%) = (pH before - pH after) / pH before × 100 (1) In formula (1): η alkali is the alkali reduction ability of the strain; pH before is the pH value of the culture medium before fermentation; pH after is the pH value of the bacterial solution after fermentation.

[0075] Table 1 Alkali reduction abilities of Bacillus halophilus and Flexibacter flavus halophilus It can be seen that both strains have good alkali reduction abilities. At pH 9.0, the alkali reduction rate of Bacillus halophilus is higher than that of Flexibacter flavus halophilus, showing a stronger alkali environment adaptation ability. As the pH value increases, the alkali reduction abilities of both strains increase, indicating that they can still maintain a certain growth activity in a high-alkali environment. Under the high-salt and high-alkali environment, the excellent performance of these two strains provides a strong basis for their application in extreme environments. Actual planting experiment The test field is a newly developed field test area for soil improvement and fertilization of saline-alkali land. The crop planted in this test area is rice, with one crop per year and a crop growth period of about 130 days. The soil type of the test area is typical soda saline-alkali soil, with a shallow groundwater depth of about 1.0 - 2.5 m, a soil texture of silty loam, a soil pH of 10.2, and an EC of 2.23 (mS·cm -1 ).

[0076] The following experimental groups were set up in the experiment: The control group without applying any modifier (T1), the application of the soil modifiers of Examples 1 - 2 of the present invention (T2 - T3), the application of the modifiers of Comparative Examples 1 - 5 (T4 - T8), and the aluminum sulfate control group T9.

[0077] Among them, the modifiers of the examples and comparative examples were evenly spread on the field surface at a rate of 100 kg / mu, and combined with a rotary tiller to plow to a soil layer of 20 - 30 cm to ensure full mixing with the soil. After application, the field was flooded and soaked for 5 - 7 days. The aluminum sulfate used in this test was industrial iron-containing aluminum sulfate, light gray granular or flaky; the application rate of aluminum sulfate was 2 t·hm -2 , and the area of each test area was 700 m 2 . Each test area was provided with independent water inlet and drainage devices. The base fertilizer was a compound fertilizer of 12 - 18 - 15%, and the application rate was 400 kg·hm -2 , and the later stage was uniformly top-dressed with 100 kg·hm -2。

[0078] The rice variety planted is Longjing 31, and its growth period is about 130 days.

[0079] Soil sample collection and determination: Soil samples were collected before the start of the experiment and after rice harvest. For each treatment, the five-point sampling method was used to dig a rectangular soil profile of 1×1.5 m, and soil samples from the soil layer of 20 - 40 cm were collected.

[0080] The collected soil samples were removed of obvious sundries such as plant roots and gravel. After the soil samples were naturally air-dried indoors, they were sieved through 2 mm and 0.25 mm sieves, and the soil salinity indexes and soil enzyme activities were determined.

[0081] The pH value of the soil was measured using a glass electrode pH meter, and the soil-water ratio was 5:1; the soil salt content was measured by the drying method; urease was measured by the sodium phenolate - sodium hypochlorite colorimetric method; sucrase was measured by the sodium thiosulfate titration method; catalase was measured by the potassium permanganate titration method; alkaline phosphatase was measured by the disodium phenyl phosphate colorimetric method. Ten samples were taken for all soil indexes, and the results were averaged.

[0082] Determination of rice yield and quality: Yield measurement of rice in each test area was carried out at the mature stage of rice.

[0083] Calculation method of soil sodium adsorption ratio: The formula (1) of soil sodium adsorption ratio (SAR) is as shown: (1) Table 3 Soil adjustment data From the data in Table 3, we can see that applying the soil conditioner of the embodiment of the present invention can effectively reduce the soil pH level and reduce the soil salt content, thereby improving the soil permeability and crop growth environment.

[0084] Table 4 Soil enzyme activities in rice roots From Tables 3 - 4, we can see that there are obvious differences in enzyme activities between the soil applied with the conditioner and the untreated soil. The soil enzyme activities of Example 1 and Example 2 are generally higher, especially the urease and sucrase activities are much higher than those of the control group and the soil without conditioner in T1. This indicates that the application of the conditioner can effectively enhance the biological activity of the soil, thereby providing a more favorable environment for the growth of rice. For Comparative Examples 1 - 5, which have changed the microbial composition and active ingredients, the soil enzyme activities have also been improved to varying degrees, but they are all lower than those of the soil in the examples, which further proves the superiority of the soil conditioner of the present invention.

[0085] It should be noted that the above embodiments are only partial embodiments of the preferred ways to implement the present invention, rather than all embodiments. Obviously, based on the above embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

Claims

1. A saline-alkali soil conditioner, characterized in that: The invention comprises the following raw material components: organic regulating components, microorganisms and their fermented products, and active regulating components.

2. The saline-alkali soil conditioner according to claim 1, characterized in that: The organic regulating component comprises earthworm castings, coconut bran decomposed matter and humic acid, and the mass ratio of the three is (10-20): (15-23): (7-10).

3. The saline-alkali soil conditioner according to claim 1, characterized in that: The microorganism and the fermentation product thereof are obtained by mixed fermentation of the screened halophilic alkaline bacillus and the salt-film yellow Campylobacter with a strain number of CGMCC No.1.16084.

4. The saline-alkali soil conditioner according to claim 3, characterized in that: The preservation number of the halophilic alkaline Bacillus is CGMCC No.70240, the preservation date is June 16, 2023, and it is deposited in the General Microbiology Center of the China Culture Collection Administration, with the address at No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing.

5. The saline-alkali soil conditioner according to claim 3, characterized in that: The active regulating component is prepared by mixing sodium alginate, spermine and brassinosteroid in a mass ratio of 1:1:

1.

6. A method for producing the saline-alkali soil conditioner according to any one of claims 1 to 5, characterized in that: The method comprises the following preparation steps: (1) Preparation of organic regulating components: The raw material coconut bran is mixed with the microbial agent in a mass ratio of 1:0.05, the moisture content is adjusted to 60%-65%, the compost is fermented for 24-26 days at a temperature of 55-65°C, the compost is turned every 3 days, the pH value is reduced to 7.2-7.5 after decomposition, and the C / N ratio is stabilized at 22-24 to obtain the coconut bran decomposed material; the earthworm manure and the coconut bran decomposed material are respectively crushed to a particle size of ≤2mm, the earthworm manure, the coconut bran decomposed material and the humic acid are mixed in a mass ratio of (10-20): (15-23): (7-10), the moisture content of the mixture is adjusted to 30%-35%, and the mixture is aged for 5 days to enhance the binding force to obtain the organic regulating component; (2) Preparation of microorganisms and their fermentation products: The halophilic alkaline Bacillus was inoculated into an activation medium A, and cultured in a shaking table at 28-30°C and a speed of 150-200 rpm for 48 hours to obtain an activated bacterial solution of the halophilic alkaline Bacillus; the salt film yellow Campylobacter was inoculated into an activation medium B, and cultured in a shaking table at 28-30°C and a speed of 120-150 rpm for 48 hours to obtain an activated bacterial solution of the salt film yellow Campylobacter; the two bacterial solutions were mixed at a volume ratio of 2:1, and inoculated into a fermentation carrier according to 8% of the mass of the fermentation carrier, and the water content was adjusted to 50%-55%, and the pH was 8.5-9.0, and fermentation was carried out for 70-90 hours, and the material was turned over every 8 hours to ensure uniform distribution of the bacteria; after the fermentation was completed, vacuum freeze drying was performed to retain the activity of the bacteria and metabolites; finally, ultrafine grinding was performed to a particle size of ≤0.1 mm, and a 200-mesh sieve was passed to obtain an off-white powder mixture, which was the microorganism and its fermentation product; (3) Preparation of improver: The organic regulating component, microorganism and its fermentation product and active regulating ingredient are mixed uniformly in a mass ratio of 20:3:1, and granulated by a twin-screw extruder granulator with a die hole diameter of 3-5 mm. The granules are dried to a moisture content of ≤8% to obtain the final product.

7. The method for producing the saline-alkali soil conditioner according to claim 6, characterized in that: The microbial agents in step (1) are EM bacteria and Bacillus subtilis, and the mass ratio of the two is 5:

3.

8. The method for producing the saline-alkali soil conditioner according to claim 6, characterized in that: According to mass percentage: the composition of activation medium A in step (2) is: 1% peptone, 0.5% yeast extract, 8% NaCl, and the balance is water, pH 8.5-9.0; the composition of medium B is: 2% glucose, 1% peptone, 5% NaCl, 0.1% MgSO4, and the balance is water, pH 8.5; the composition of fermentation carrier is: 60% corn cob powder, 30% soybean meal powder, and 10% diatomaceous earth, and the water content is adjusted to 50%-55%, and the pH is 8.5-9.0.

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