Ecological balance fertilizer for yield increase and disease resistance of peanuts and preparation method of ecological balance fertilizer

Abstract

The invention relates to the technical field of fertilizer preparation, and discloses an ecological balance fertilizer for yield increase and disease resistance of peanuts and a preparation method of the ecological balance fertilizer. The preparation process comprises the following steps: constructing a PLGA core containing trichoderma harzianum spores and magnesium carbonate through a micro-fluidic chip low-temperature water-in-oil emulsion method; coating bacillus amyloliquefaciens and potassium silicate with ultraviolet-induced cross-linked temperature-sensitive hydrogel to form a middle layer; loading rhizobium by using aminated mesoporous S < iO2 >, and spraying and assembling an enzyme response shell through a fluidized bed; finally, the hydroxyapatite nanorod and a binder are combined and granulated and formed through a fluidized bed. Precise controlled release of functional bacteria and nutrients is realized by constructing a temperature-sensitive-enzyme response type release system, and the activity of a fungicide is guaranteed to be preserved by virtue of trichoderma harzianum-rhizobium synergistic interaction and silicon bond linkage soil remediation in combination with a low-temperature fluidized bed process, so that a'fertilizer-bacterium-soil 'ecological cycle system is finally constructed.

Description

Technical Field

[0001] The invention relates to the technical field of fertilizer preparation, in particular to an ecologically balanced fertilizer for increasing peanut yield and resisting disease, and a preparation method thereof. Background Art

[0002] In agricultural production, the coordinated application of chemical fertilizers and biofertilizers is a key means of balancing high crop yields and soil health. Although traditional chemical fertilizers can quickly replenish nitrogen, phosphorus, and potassium, their rapid release characteristics can easily lead to nutrient loss and soil compaction. Biofertilizers, on the other hand, have difficulty achieving the sustained effect of "using bacteria to promote growth and suppress disease" due to problems such as unstable bacterial activity and low rhizosphere colonization rates. With the intensification of continuous cropping problems and soil acidification, single-function fertilizers can no longer meet the complex needs of crops for stress resistance, disease resistance, and efficient nutrient utilization throughout their growth period. There is an urgent need to develop intelligent fertilizer systems that combine environmental response release and ecological regulation functions.

[0003] In current technologies, slow-release fertilizers mostly achieve controlled release of nitrogen and phosphorus through physical barriers of coating materials. However, the delivery of trace elements and functional bacteria lacks temporal and spatial coordination, resulting in a mismatch between nutrient release and crop needs. During the granulation process, biological fertilizers often damage bacterial activity due to high temperature and high pressure, and the difference in physical and chemical properties between bacterial agents and chemical fertilizers can easily lead to component antagonism, resulting in functional loss. In addition, the problems of aluminum ion toxicity and phosphorus immobilization in acidified soils have long existed. Existing fertilizers are difficult to repair the soil microenvironment while providing fertilizer, and the contradiction between the mechanical strength of the particles and the disintegration rate further limits the precise release of functional components.

[0004] The essence of the above problem lies in the fact that traditional fertilizer design does not regard "nutrients-microbial communities-soil" as a dynamically interacting organic whole. The functional components are isolated and dispersed, and cannot respond to the coordinated changes in crop growth stages and rhizosphere environment. Summary of the Invention

[0005] In response to the shortcomings of the existing technology, the present invention provides an ecologically balanced fertilizer for increasing peanut production and resisting diseases and a preparation method thereof, which solves the problems of nutrient release in traditional fertilizers being out of sync with crop needs, insufficient protection of bacterial fertilizer activity, and difficulty in repairing soil acidification.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0007] The first aspect of the present invention provides an ecologically balanced fertilizer for increasing peanut yield and resisting disease, comprising the following components by weight percentage:

[0008] Core functional microspheres 55%-65%, from inside to outside include:

[0009] PLGA core: comprising a copolymer of lactic acid and glycolic acid, wherein the particle size of the PLGA core is 80 μm-150 μm;

[0010] The PLGA core is composed of a lactic acid-glycolic acid copolymer, and its molecular weight is controlled at 12-18 kDa to regulate the degradation rate. The magnesium carbonate dispersed in the core is gradually released during the degradation process of PLGA, reacting with the lactic acid degradation products to generate alkaline ions (CO3 2- ), maintaining the internal pH of the microspheres at 7.0 ± 0.2, thereby neutralizing the acidic soil environment and eliminating the mutual inhibition between Trichoderma harzianum and Rhizobium. The addition of L-malic acid further forms a complex with magnesium ions, providing a carbon source for Rhizobia and promoting nitrogenase activity.

[0011] Thermosensitive hydrogel middle layer: coated on the surface of the PLGA core, comprising a copolymer of N-isopropylacrylamide and acrylic acid, the thickness of the thermosensitive hydrogel middle layer is 15 μm-25 μm;

[0012] The thermosensitive layer is made of N-isopropylacrylamide-acrylic acid copolymer, whose phase transition temperature matches the ground temperature threshold during the flowering and needle-setting period of peanuts. When the ground temperature exceeds the critical value, the hydrogel undergoes hydrophobic contraction, releasing Bacillus amyloliquefaciens and potassium silicate. Bacillus amyloliquefaciens suppresses soil-borne pathogens by secreting antimicrobial peptides, while potassium silicate enhances the lignification of the peanut cell walls, forming a physical barrier against disease.

[0013] Mesoporous SiO2 shell: coated on the surface of the thermosensitive hydrogel intermediate layer, formed by mesoporous SiO2 nanosheets with a pore size of 3.0nm-5.0nm modified by 3-aminopropyltriethoxysilane, with an amino modification density of 2.5μmol·m 2 -3.5 μmol·m 2 The shell contains 1.0×10 rhizobia. 8 CFU per gram shell up to 2.0 × 10 8 CFU per gram of shell, and methyl jasmonate;

[0014] After the mesoporous SiO2 shell was modified with 3-aminopropyltriethoxysilane, the amino density reached 2.5-3.5 μmol / m 2 The mesopores are designed to anchor rhizobia through electrostatic adsorption. The mesopores are sized to match the molecular size of β-glucosidase secreted by peanut roots. When the concentration of root secretions increases, enzymatic hydrolysis disrupts the mesoporous structure, precisely releasing rhizobia into the rhizosphere. Methyl jasmonate diffuses simultaneously, activating plant resistance signaling pathways.

[0015] 8%-15% of hydroxyapatite nanorods, wherein the nanorods are 80nm-120nm in length, 15nm-25nm in diameter, and are surface-loaded with zinc, boron, and molybdenum;

[0016] The Zn, B, and Mo elements loaded on the surface of hydroxyapatite nanorods enter the root hair cells through the size effect. The nanorods dissociate in the weakly acidic environment of the rhizosphere (pH ≈ 5.5), and the released Zn 2+ Activate dehydrogenase activity, MoO4 2- As a nitrogenase cofactor, it improves the nitrogen fixation efficiency of rhizobia.

[0017] 4%-8% H2S slow-release precursor, which is L-cysteine loaded on a ZIF-8 metal-organic framework, where the drug loading of L-cysteine is 10%-15%;

[0018] L-cysteine loaded on ZIF-8 is released under low pH conditions in the rhizosphere and metabolized by rhizobia to produce H2S. H2S inhibits complex III of the mitochondrial electron transport chain, reducing oxygen tension within the nodule and creating an anaerobic microenvironment that protects nitrogenase activity while inducing the expression of endogenous plant disease resistance proteins (PR-1 and PR-5).

[0019] The binder is 8%-15%, and is composed of humic acid and sodium alginate in a mass ratio of 3:1.

[0020] Preferably, the molar ratio of lactic acid to glycolic acid is 75:25-80:20, the molecular weight is 12KDa-18KDa, and magnesium carbonate with a particle size of 5μm-15μm, 1.0×10 6 CFU per gram of PLGA core to 5.0 × 10 6 CFU per gram of PLGA core, and L-malic acid.

[0021] Preferably, the molar ratio of N-isopropylacrylamide to acrylic acid is 8:2 to 9:1, and the phase transition temperature of the copolymer is 24°C-26°C. The thermosensitive hydrogel middle layer is loaded with 5.0×10 7 CFU per gram of the middle layer to 1.0 × 10 8 CFU per gram of middle layer, and potassium silicate.

[0022] Preferably, the thickness of the mesoporous SiO2 shell is 5 μm-10 μm.

[0023] Preferably, the zinc, boron and molybdenum loadings of the hydroxyapatite nanorods are 4%-6%, 2%-4% and 1%-3%, respectively, based on the total weight of the nanorods.

[0024] Preferably, the molecular weight of humic acid in the binder is 1500Dal-2000Dal.

[0025] A second aspect of the present invention provides a method for preparing an ecologically balanced fertilizer for increasing peanut yield and resisting disease, comprising the following steps:

[0026] Preparation of the PLGA core: Lactic acid-glycolic acid copolymer, magnesium carbonate, Trichoderma harzianum chlamydospores, and L-malic acid were dissolved in dichloromethane to form an 8%-12% solution. The solution was passed through a microfluidic chip at a water-to-oil ratio of 1:4 to 1:6 at 10°C-20°C to form a water-in-oil emulsion. The solvent was evaporated for 12-24 hours to obtain the PLGA core.

[0027] The PLGA cores are prepared on a microfluidic chip at 10-20°C, avoiding the inactivation of the bacterial agent caused by traditional high-temperature granulation. Silicone oil is used as the oil phase to reduce shear forces, ensuring a survival rate of >95% for Trichoderma harzianum spores.

[0028] Thermosensitive hydrogel coating: N-isopropylacrylamide, acrylic acid, Bacillus amyloliquefaciens and potassium silicate were mixed to prepare thermosensitive hydrogel prepolymer solution. The PLGA core was immersed in the prepolymer solution. Under nitrogen protection, the temperature was measured at a wavelength of 360nm-370nm and an intensity of 8mW / cm 2 -12mW / cm 2 UV irradiation for 2-5 minutes to form an intermediate layer;

[0029] Thermosensitive hydrogel polymerization is initiated using 360-370nm UV light to avoid the toxicity of thermal initiators to Bacillus amyloliquefaciens. Irradiation is performed under nitrogen for 2-5 minutes to ensure uniform and controllable thickness of the intermediate layer.

[0030] Assembly of mesoporous SiO2 shell: Mesoporous SiO2 nanosheets were modified with 3-aminopropyltriethoxysilane and adsorbed with a rhizobium suspension at a pH of 7.0-8.0 for 12-24 hours to obtain rhizobium-loaded mesoporous SiO2. The mesoporous SiO2 was then coated onto the surface of the intermediate layer using a fluidized bed spraying process at an inlet air temperature of 30°C-40°C and an atomization pressure of 0.2MPa-0.4MPa to form a shell.

[0031] Fluidized bed spraying achieves uniform coating of the mesoporous SiO2 shell. The electrostatic adsorption efficiency of amino-modified mesoporous SiO2 and rhizobia is >90%, far exceeding the loading level of physical mixing method (<50%).

[0032] Composite granulation: The core microspheres, hydroxyapatite nanorods, H2S slow-release precursor and binder are mixed and granules with a particle size of 2mm-4mm are prepared by a fluidized bed granulation process at an inlet air temperature of 40℃-50℃.

[0033] Preferably, in the PLGA core preparation step, the oil phase is silicone oil with a viscosity of 50 MPa·s-100 MPa·s.

[0034] Preferably, the OD600 value of the rhizobium suspension in the mesoporous SiO2 shell assembly step is 0.8-1.2.

[0035] The present invention provides an ecologically balanced fertilizer for increasing peanut production and resisting disease, and a preparation method thereof.

[0036] Beneficial effects:

[0037] 1. The present invention breaks through the limitation of "one-time release" of traditional fertilizers by dynamically matching the multi-layer coating structure with soil environmental factors. The phase change of the thermosensitive layer triggers the on-demand release of Bacillus amyloliquefaciens, the enzyme-responsive shell directionally transports rhizobia to the root action site, and the ZIF-8 carrier delays the oxidative loss of L-cysteine, forming a temporal synergy of "disease resistance, growth promotion, and stress resistance", significantly improving the utilization efficiency of nutrients and biological functional factors.

[0038] 2. The cross-scale metabolic interaction between Trichoderma harzianum and Rhizobium in the present invention activates the nitrogen fixation potential of the roots, and at the same time inhibits soil-borne diseases by secreting antibacterial substances. The root silicification induced by the slow release of potassium silicate cooperates with the colonization of the bacterial community, forming a dual protection of physical barrier and biological antagonism, breaking the technical bottleneck of single bacterial species in traditional bacterial fertilizers that are easily disturbed by the environment.

[0039] 3. The cross-scale metabolic interaction between Trichoderma harzianum and Rhizobium in the present invention activates the nitrogen fixation potential of the roots, and at the same time inhibits soil-borne diseases by secreting antibacterial substances. The root silicification induced by the slow release of potassium silicate cooperates with the colonization of the bacterial community, forming a dual protection of physical barrier and biological antagonism, breaking the technical bottleneck of single bacterial species in traditional bacterial fertilizers that are easily disturbed by the environment.

[0040] 4. The microfluidic low-temperature granulation process of the present invention achieves dense encapsulation of the PLGA core through interfacial tension regulation. Combined with fluidized bed airflow suspension technology, it takes into account both the mechanical strength of the particles and the protection of the bacterial agent activity. The intelligent disintegration characteristics of the binder system ensure that the release of functional components is precisely synchronized with the root metabolic cycle, providing a feasible path for large-scale production.

[0041] 5. The present invention uses silicon as a link to connect the improvement of root stress resistance, the proliferation of beneficial bacteria and the improvement of soil aggregate structure, and build a virtuous cycle of "fertilizer nourishes soil and soil promotes growth". This design deeply integrates the reduction of chemical fertilizers, biological control substitution and soil health maintenance, and promotes the transformation of agricultural inputs from "single production increase" to "ecological balance". BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 The figure is a flow chart of the preparation method of the present invention. DETAILED DESCRIPTION

[0043] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the present specification. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0044] Please see the attached Figure 1 The present invention provides an ecologically balanced fertilizer for increasing peanut yield and resisting disease and a preparation method thereof through the following multiple embodiments. The specific contents are as follows:

[0045] Example 1:

[0046] Step 1: PLGA core preparation

[0047] 12 g of a copolymer of lactic acid and glycolic acid (molar ratio 77:23) (molecular weight 15 kDa), 13 g of magnesium carbonate (particle size 10 μm), 3.0 × 10 6 CFU / gPLGA core) and 0.5 g of L-malic acid were dissolved in dichloromethane to prepare a 10% w / v solution;

[0048] A W / O emulsion was formed at 15°C using a microfluidic chip with a flow rate ratio of 1:5 between the aqueous phase (2% PVA) and the oil phase (silicone oil, viscosity 75 MPa·s);

[0049] The solvent was evaporated for 18 h to obtain a PLGA core with a particle size of 115 μm.

[0050] Step 2: Thermosensitive hydrogel coating

[0051] N-isopropylacrylamide was copolymerized with acrylic acid (molar ratio 8.5:1.5), and Bacillus amyloliquefaciens (7.5×10 7 CFU / g middle layer) with potassium silicate 10%;

[0052] The PLGA core was immersed in the prepolymer solution and the PLGA core was irradiated under nitrogen at a wavelength of 365 nm and an intensity of 10 mW / cm 2 After 3.5 min of ultraviolet irradiation, an intermediate layer with a thickness of 20 μm was formed.

[0053] Step 3: Mesoporous SiO2 Shell Assembly

[0054] Mesoporous SiO2 nanosheets with a pore size of 4.0 nm were modified with APTES (amino group density 3.0 μmol / m 2 ), adsorbed with rhizobium suspension (OD600 = 1.0) at pH 7.5 for 18 h;

[0055] A shell with a thickness of 7.5 μm was formed by fluidized bed spraying (inlet air temperature 35° C., atomization pressure 0.3 MPa).

[0056] Step 4: Composite granulation

[0057] Core microspheres (60%), hydroxyapatite nanorods (length 100 nm, diameter 20 nm, Zn 5%, B 3%, Mo 2%) 11.5%, H2S sustained-release precursor (L-cysteine loading 12.5%) 6% and binder (humic acid: sodium alginate = 3:1) 12.5% were mixed;

[0058] The fluidized bed granulation (inlet air temperature 45 ° C) was used to produce particles with a particle size of 3 mm.

[0059] Example 2:

[0060] Step 1: PLGA core preparation

[0061] 12 g of a copolymer of lactic acid and glycolic acid (molar ratio 75:25) (molecular weight 12 kDa), 10 g of magnesium carbonate (particle size 5 μm), 1.0 × 10 6 CFU / gPLGA core) and 0.3 g of L-malic acid were dissolved in dichloromethane to prepare an 8% w / v solution;

[0062] A W / O emulsion was formed at 10°C using a microfluidic chip with a flow rate ratio of 1:4 between the water phase and the oil phase (silicone oil, viscosity 50 MPa·s);

[0063] The solvent was evaporated for 12 h to obtain a PLGA core with a particle size of 80 μm.

[0064] Step 2: Thermosensitive hydrogel coating

[0065] N-isopropylacrylamide was copolymerized with acrylic acid (molar ratio 8:2), and Bacillus amyloliquefaciens (5.0×10 7 CFU / g middle layer) with potassium silicate 8%;

[0066] UV radiation wavelength 360nm, intensity 8mW / cm 2 , time 2min, forming an intermediate layer with a thickness of 15μm.

[0067] Step 3: Mesoporous SiO2 Shell Assembly

[0068] Mesoporous SiO2 pore size 3.0nm, amino density 2.5μmol / m 2 , Rhizobium suspension OD600=0.8;

[0069] The fluidized bed spraying air inlet temperature is 30°C, the atomization pressure is 0.2 MPa, and the shell thickness is 5 μm.

[0070] Step 4: Composite granulation

[0071] Core microspheres 55%, hydroxyapatite nanorods (Zn4%, B2%, Mo1%) 8%, H2S sustained-release precursor (drug loading 10%) 4% and binder 8%;

[0072] The inlet air temperature was 40°C, and the particles with a particle size of 2 mm were obtained.

[0073] Example 3:

[0074] Step 1: PLGA core preparation

[0075] 12 g of a copolymer of lactic acid and glycolic acid (molar ratio 80:20) (molecular weight 18 kDa), 15 g of magnesium carbonate (particle size 15 μm), 5.0 × 10 6 CFU / gPLGA core) and 0.8 g of L-malic acid were dissolved in dichloromethane to prepare a 12% w / v solution;

[0076] A W / O emulsion was formed at 20°C using a microfluidic chip with a flow rate ratio of 1:6 between the water phase and the oil phase (silicone oil, viscosity 100 MPa·s);

[0077] The solvent was evaporated for 24 h to obtain a PLGA core with a particle size of 150 μm.

[0078] Step 2: Thermosensitive hydrogel coating

[0079] N-isopropylacrylamide was copolymerized with acrylic acid (molar ratio 9:1), and Bacillus amyloliquefaciens (1.0×10 8 CFU / g middle layer) with potassium silicate 12%;

[0080] UV radiation wavelength 370nm, intensity 12mW / cm 2 , time 5min, forming an intermediate layer with a thickness of 25μm.

[0081] Step 3: Mesoporous SiO2 Shell Assembly

[0082] Mesoporous SiO2 pore size 5.0nm, amino density 3.5μmol / m 2 , Rhizobium suspension OD600=1.2;

[0083] The fluidized bed spraying air inlet temperature is 40°C, the atomization pressure is 0.4 MPa, and the shell thickness is 10 μm.

[0084] Step 4: Composite granulation

[0085] Core microspheres 65%, hydroxyapatite nanorods (Zn6%, B4%, Mo3%) 15%, H2S sustained-release precursor (drug loading 15%) 8% and binder 15%;

[0086] The inlet air temperature was 50°C, and the particles with a particle size of 4 mm were obtained.

[0087] Comparative Examples 1-7:

[0088] Comparative Example 1:

[0089] Compared with Example 1, the difference is:

[0090] Magnesium carbonate and L-malic acid were not added to the PLGA core, and only lactic acid-glycolic acid copolymer and Trichoderma harzianum chlamydospores were retained. The other components and process parameters were the same.

[0091] Comparative Example 2:

[0092] Compared with Example 1, the difference is:

[0093] The thermosensitive hydrogel middle layer was replaced with ordinary polyacrylic acid hydrogel (without thermosensitive properties), and Bacillus amyloliquefaciens and potassium silicate were not loaded. The other components and process parameters were the same.

[0094] Comparative Example 3:

[0095] Compared with Example 1, the difference is:

[0096] The mesoporous SiO2 shell was not amino-modified, and unmodified mesoporous SiO2 nanosheets were directly used to adsorb rhizobia. The other components and process parameters were the same.

[0097] Comparative Example 4:

[0098] Compared with Example 1, the difference is:

[0099] The hydroxyapatite nanorods were replaced by ordinary calcium hydrogen phosphate powder (particle size 1-5 μm), and no zinc, boron, or molybdenum elements were loaded. The other components and process parameters were the same.

[0100] Comparative Example 5:

[0101] Compared with Example 1, the difference is:

[0102] The H2S slow-release precursor was replaced by unencapsulated L-cysteine powder (directly mixed with fertilizer), and ZIF-8 loading was not used. The other components and process parameters were the same.

[0103] Comparative Example 6:

[0104] Compared with Example 1, the difference is:

[0105] The PLGA core was prepared by using a high-temperature (50°C) emulsification solvent evaporation method instead of a microfluidic low-temperature process. The remaining components and process parameters were the same.

[0106] Comparative Example 7:

[0107] Compared with Example 1, the difference is:

[0108] The fluidized bed process was not used in the composite granulation, but conventional extrusion granulation (temperature 80°C) was used instead, with the other components and process parameters being the same.

[0109] Test Example 1-5:

[0110] Test Example 1: Bacterial Agent Activity and Symbiotic Effect Test

[0111] Purpose of the experiment:

[0112] Verify the pH buffering effect of the PLGA core (Comparative Example 1), the effect of amino-modified mesoporous SiO2 on the adsorption of rhizobia (Comparative Example 3), and the protective effect of the microfluidic low-temperature process on the activity of the bacterial agent (Comparative Example 6).

[0113] Experimental steps:

[0114] Sample preparation:

[0115] Test groups: Example 1, Comparative Example 1 (no magnesium carbonate / L-malic acid), Comparative Example 3 (unmodified mesoporous SiO2), Comparative Example 6 (high temperature process PLGA core);

[0116] Soil treatment: Sandy loam soil (pH 5.8) was divided into 4 groups of potted plants, and each group was fertilized with 2 g / kg soil;

[0117] Culture conditions: constant temperature of 25°C, humidity of 60%, light intensity of 12h / d, continuous culture for 14 days;

[0118] Rhizobium adsorption rate test:

[0119] Sampling: On the 7th day of incubation, rhizosphere soil (0-5 cm depth) was collected, and three random mixed samples were taken from each pot;

[0120] Colony count:

[0121] The soil suspension was diluted to 10 -5 , spread on YMA medium (containing Congo red);

[0122] After incubation at 30°C for 48 h, the number of typical rhizobia colonies (CFU / g soil) was counted;

[0123] Trichoderma harzianum survival rate test:

[0124] Spore extraction: 0.1 g of PLGA core was dissolved in 0.1 M PBS (pH 7.4) and shaken to release spores.

[0125] Germination rate determination:

[0126] The spore suspension was spread on PDA medium and cultured at 25°C for 24 h;

[0127] The proportion of germinated spores was counted under a microscope (germination standard: germ tube length ≥ spore diameter);

[0128] Observation of mutual exclusivity of bacterial communities.

[0129] Co-culture experiments:

[0130] Take the rhizosphere soil suspension (10 -3 dilution), inoculated into liquid LB medium;

[0131] Incubate at 30°C in a shaking incubator for 72 h, and observe the turbidity of the bacterial solution and the morphology of the sediment;

[0132] PCR was used to detect the abundance ratio of Trichoderma harzianum (ITS sequence) and Rhizobium (nodC gene).

[0133] Experimental data:

[0134] Table 1 Test results of bacterial agent activity and symbiotic effect

[0135]

[0136] Data Description:

[0137] Rhizobium adsorption rate: Example 1 is significantly higher than that of Comparative Example 3 (unmodified) due to the directional adsorption of amino-modified mesoporous SiO2;

[0138] Survival rate of Trichoderma harzianum: The spore germination rate of Comparative Example 6 (high temperature process) decreased by 23%, proving the necessity of low temperature process;

[0139] Bacterial coexistence status: In Comparative Example 1 (no pH buffer), Trichoderma harzianum inhibited the growth of rhizobia (abundance ratio imbalance).

[0140] Experimental summary: This experiment verified the key role of multi-level structure design and material interface regulation in ecologically balanced fertilizers on the activity of bacterial agents and symbiotic balance. Magnesium carbonate and L-malic acid were introduced into the PLGA core. Through the acidification reaction of lactic acid degradation and the alkaline neutralization reaction of magnesium carbonate, the pH inside the microspheres was dynamically maintained stable (7.0±0.2), which effectively alleviated the mutual inhibition effect between Trichoderma harzianum and Rhizobium in an acidic environment. Experimental data showed that when the buffer system was missing (Comparative Example 1), the colonization efficiency of Rhizobia in the rhizosphere decreased by 62%, and the bacterial abundance ratio was unbalanced (Trichoderma harzianum dominated), which directly confirmed the necessity of pH regulation for bacterial symbiosis.

[0141] The amino modification of the mesoporous SiO2 shell significantly improved the directional anchoring efficiency of rhizobia through the electrostatic adsorption mechanism. The amino density (2.5-3.5μmol / m 2 ) matches the negative charge on the bacterial surface, increasing the rhizobium adsorption rate by more than 14 times compared to the unmodified group (Comparative Example 3). This result synergizes with the enzyme-responsive release logic of mesoporous SiO2: when the roots secrete β-glucosidase, the enzyme molecules (approximately 4.2nm in size) can penetrate the mesopores (3.0-5.0nm) and destroy the pore structure, achieving targeted release of rhizobia, thereby avoiding the premature inactivation of the agent caused by traditional physical mixing.

[0142] In addition, the microfluidic low-temperature process (10-20°C) combined with the low-shear properties of silicone oil increased the survival rate of Trichoderma harzianum spores to 95.3%, which is 23% higher than the higher-temperature emulsification method (Comparative Example 6). This difference stems from the protection mechanism for heat-sensitive bacterial agents during the preparation of the PLGA core: the low-temperature environment inhibits the mechanical damage to the spore cell membrane caused by the sudden change in the interfacial tension of the emulsion, while avoiding the heat stress effect during the solvent volatilization stage. This process innovation provides a key technical guarantee for the retention of the activity of functional bacteria, and together with the environmental response logic of the three-layer structure, it constructs a synergistic enhancement system of bacteria-fertilizer-soil.

[0143] Test Example 2: Environmental Response and Release Behavior Test

[0144] Purpose of the experiment:

[0145] Verify the temperature-responsive release characteristics of the thermosensitive hydrogel (Comparative Example 2), the regulatory effect of ZIF-8 loading on the sustained release of L-cysteine (Comparative Example 5), and the enzyme-triggered release mechanism of the mesoporous SiO2 shell (self-verification of Example 1).

[0146] Experimental steps:

[0147] Temperature response release rate test:

[0148] Sample group: Example 1, Comparative Example 2 (ordinary hydrogel, non-thermosensitive).

[0149] Experimental conditions:

[0150] Take 0.5 g of fertilizer granules and disperse them in 50 mL of PBS buffer (pH 6.0);

[0151] 2. Constant temperature oscillation (120 rpm) at 24°C (lower ground temperature threshold during peanut flowering) and 30°C (extreme high temperature simulation);

[0152] Samples were taken at 0 h, 6 h, 24 h, and 48 h, and the amount of Bacillus amyloliquefaciens released (CFU / mL) was determined.

[0153] H2S slow-release kinetics test:

[0154] Sample groups: Example 1, Comparative Example 5 (not embedded with L-cysteine).

[0155] Experimental methods:

[0156] 0.5 g of fertilizer granules were placed in a closed reactor and simulated rhizosphere solution (pH 5.5) was added;

[0157] Nitrogen was continuously introduced to remove oxygen, and gas samples were taken every 2 hours;

[0158] The cumulative release of H2S (μg / g fertilizer) was determined by methylene blue spectrophotometry.

[0159] Enzyme-triggered release verification:

[0160] Sample group: Example 1.

[0161] Operation process:

[0162] 0.5 g of fertilizer granules were soaked in PBS solution (pH 6.0) containing β-glucosidase (1 U / mL); the control group was treated with the same solution without enzyme addition;

[0163] Samples were taken every 4 h within 24 h to determine the amount of rhizobium released (CFU / mL).

[0164] Experimental data:

[0165] Table 2 Environmental response and release behavior test results

[0166]

[0167]

[0168] Data Description:

[0169] Temperature-responsive release: Example 1 shows a 316% increase in the release of Bacillus amyloliquefaciens at 30°C compared to 24°C, while there is no significant difference in Comparative Example 2 (ordinary hydrogel), demonstrating the effectiveness of the temperature-sensitive layer phase transition logic.

[0170] H2S sustained release: The ZIF-8 loading in Example 1 extended the sustained release period of L-cysteine to 48 h, which was more in line with the metabolic needs of rhizobia than the burst release in Comparative Example 5 (unencapsulated) (44% reduction in release in 48 h);

[0171] Enzyme-triggered release: After adding β-glucosidase, the release of rhizobia increased by 15 times, verifying the enzyme response mechanism of mesoporous SiO2.

[0172] Experimental summary: This experiment reveals the precise regulation mechanism of the release behavior of functional components by the environmentally responsive material system in ecologically balanced fertilizers. The thermosensitive hydrogel middle layer achieves dynamic matching with the rising ground temperature during the flowering period of peanuts through the phase change characteristics of the copolymer of N-isopropylacrylamide and acrylic acid (phase change temperature 24-26°C). When the soil temperature exceeds the critical threshold, the hydrophobic contraction of the hydrogel forces the release of Bacillus amyloliquefaciens and potassium silicate. Experimental data show that the release of bacterial agents at 30°C is 316% higher than that at room temperature, while ordinary hydrogel (Comparative Example 2) has no significant response. This feature is highly consistent with the physiological need of peanuts to simultaneously enhance disease resistance during the growth period, verifying the effectiveness of the temperature-triggered release logic.

[0173] The ZIF-8 metal-organic framework (MOF) acts as a sustained-release carrier for L-cysteine, regulating the rate of H2S production through its micropore confinement effect and pH-responsive properties. In the weakly acidic rhizosphere environment (pH 5.5), the ZIF-8 framework gradually dissociates and releases L-cysteine. Experimental data demonstrating H2S metabolism by rhizobia show that the 48-hour cumulative release in Example 1 is 44% lower than that obtained by directly adding unencapsulated L-cysteine (Comparative Example 5). This demonstrates that the ZIF-8 carrier effectively prevents the toxic effects of explosive H2S release on the root system and prolongs its duration of action in inducing systemic resistance.

[0174] The enzyme-responsive release mechanism of the mesoporous SiO2 shell is achieved through a precise match of pore size to the molecular size of β-glucosidase (3.0-5.0 nm). Experimental data showed that in a simulated rhizosphere environment with the addition of β-glucosidase, the release of rhizobia increased 15-fold compared to the absence of enzyme, demonstrating that enzymatic hydrolysis can target the mesoporous structure. This design allows the release of rhizobia only in response to peanut root secretions, avoiding the colonization failure of microorganisms in traditional fertilizers due to premature exposure, thereby significantly improving the efficiency of symbiotic nitrogen fixation.

[0175] Test Example 3: Nutrient Utilization and Disease Resistance Test

[0176] Purpose of the experiment:

[0177] Verify the enhanced effect of hydroxyapatite nanorods on the sustained release of trace elements (Comparative Example 4), the regulation of the disease-resistant function of the thermosensitive hydrogel middle layer (Comparative Example 2), and the effect of potassium silicate release on the stress resistance of peanuts.

[0178] Experimental steps:

[0179] Trace element release rate test:

[0180] Sample group: Example 1, Comparative Example 4 (ordinary calcium hydrogen phosphate powder).

[0181] Operation process:

[0182] Mix 0.5 g of fertilizer granules with 50 g of sandy loam (pH 5.8) and place in a petri dish;

[0183] 2. Add deionized water daily to maintain humidity and culture continuously for 21 days;

[0184] Rhizosphere soil (0-5 cm depth) was collected weekly, and the cumulative release of Zn, B, and Mo (μg / g soil) was determined by ICP-OES.

[0185] Disease resistance induction effect test:

[0186] Sample group: Example 1, Comparative Example 2 (ordinary hydrogel, non-thermosensitive).

[0187] Pathogen inoculation:

[0188] Peanut seedlings (3-leaf stage) were transplanted into pots containing fertilizer (2 g / kg soil);

[0189] After 7 days of cultivation, the rhizosphere was inoculated with a spore suspension of Fusarium spp. (1×10 6 CFU / mL);

[0190] The plants were observed for 14 days, and the incidence of root rot (percentage of lesion area) and plant mortality were calculated.

[0191] Potassium silicate release test:

[0192] Sample group: Example 1.

[0193] Determination method:

[0194] Take 0.5 g of fertilizer granules and soak them in simulated rhizosphere solution (pH 6.0);

[0195] The mixture was shaken (100 rpm) at 25 °C and samples were taken at 12 h, 24 h, and 48 h;

[0196] The silicon concentration (mg / L) in the solution was determined by ammonium molybdate colorimetry.

[0197] Experimental data:

[0198] Table 3 Nutrient utilization and disease resistance test results

[0199]

[0200] Data Description:

[0201] Zn release: The nanorod structure in Example 1 increased Zn release by 173% compared to Comparative Example 4 (normal phosphate), verifying nanoscale synergy.

[0202] Disease resistance: The incidence of root rot in Example 1 was reduced by 71% compared with that in Comparative Example 2 (ordinary hydrogel), demonstrating the key role of thermosensitive release of Bacillus amyloliquefaciens.

[0203] Potassium silicate release: The silicon release in Example 1 reaches 36.8 mg / L in 48 hours, which matches the peak silicon demand of peanuts during flowering.

[0204] Experimental summary: This experiment confirmed the synergistic effect of nanostructure design and environmental response release logic in ecologically balanced fertilizers on nutrient efficiency and disease resistance. Hydroxyapatite nanorods (80-120nm long) continuously release trace elements such as Zn, B, and Mo in the slightly acidic environment of the rhizosphere through the surface weak acid dissociation mechanism. Experimental data show that its Zn release is 173% higher than that of ordinary calcium hydrogen phosphate (Comparative Example 4), which is due to the high specific surface area of the nanorods (about 120m 2 / g) is compatible with the absorption size of root hair cells, making Zn 2+ It is slowly released in a form that can be used by plants, avoiding the loss of trace elements in traditional phosphate fertilizers due to fixation.

[0205] The temperature-responsive properties of the thermosensitive hydrogel middle layer precisely regulate the release sequence of Bacillus amyloliquefaciens. When the soil temperature reaches the threshold for peanut flowering (24-26°C), the hydrophobic contraction of the hydrogel triggers the release of the bacterial agent. The incidence of root rot in the experimental group is 71% lower than that of the control group 2, which has no thermosensitive properties. This result is consistent with the mechanism by which Bacillus amyloliquefaciens secretes antimicrobial lipopeptides (such as surfactin) to directly inhibit Fusarium infection. At the same time, the synergistic release of potassium silicate enhances the silicification of plant cell walls, forming a physical disease-resistant barrier.

[0206] The phased release of potassium silicate further demonstrates its growth-stage-matched design. Experimental data showed that silicon release reached 36.8 mg / L within 48 hours, coinciding with the peak silicon demand during peanut flowering. Silicon promotes cell wall thickening and lignin deposition, enhancing both disease resistance and lodging resistance. This synergistic "nutrient-disease resistance" mechanism overcomes the technical limitations of traditional fertilizers, which separate nutrient supply from biological control, and demonstrates the innovative nature of cross-scale functional integration.

[0207] Test Example 4: Process Stability and Particle Performance Test

[0208] Purpose of the experiment:

[0209] Verify the improvement of the mechanical strength of the particles by the microfluidic low-temperature process (Comparative Example 6), the protective effect of fluidized bed granulation on the survival rate of the bacterial agent (Comparative Example 7), and the regulation of the particle disintegration rate by the binder system.

[0210] Experimental steps:

[0211] Particle compressive strength test:

[0212] Sample groups: Example 1, Comparative Example 6 (PLGA core prepared by high temperature emulsification method).

[0213] Test method:

[0214] 50 particles (2.0-2.5 mm in diameter) were randomly selected and the single-particle crushing force was measured using a universal material testing machine (speed 1 mm / min);

[0215] Calculate the mean and standard deviation to screen out groups with significant differences in crushing force.

[0216] Bacterial agent survival rate test:

[0217] Sample group: Example 1, Comparative Example 7 (conventional extrusion granulation).

[0218] Operation process:

[0219] 0.5 g of the granules after granulation were taken, ground and dissolved in 10 mL of PBS buffer (pH 7.0);

[0220] Serial dilution to 10 -4 , spread on LB solid medium;

[0221] The cells were cultured at 30°C for 24 h, and the survival rate of Bacillus amyloliquefaciens (CFU / g particles) was calculated.

[0222] Disintegration rate observation:

[0223] Sample group: Example 1.

[0224] Simulation experiment:

[0225] 5 g of particles were placed in a beaker and 200 mL of simulated rhizosphere solution (pH 6.0) was added;

[0226] The mixture was stirred magnetically (50 rpm), and the particle morphology was observed every 10 min and the complete disintegration time was recorded. The microstructural differences between the disintegrated residue and the initial particles were compared.

[0227] Experimental data:

[0228] Table 4 Process stability and particle performance test results

[0229]

[0230]

[0231] Data Description:

[0232] Compressive strength: Due to the microfluidic low-temperature process to form a dense PLGA core, the compressive strength of Example 1 is increased by 98% compared with that of Comparative Example 6;

[0233] Survival rate of bacterial agent: The survival rate of fluidized bed low-temperature granulation (Example 1) was 521% higher than that of extrusion granulation (Comparative Example 7), proving that the low-temperature process protects the activity of the bacterial agent;

[0234] Disintegration time: The particles of Example 1 completely disintegrated in the simulated rhizosphere solution within 38 minutes, matching the release rhythm of root exudates.

[0235] Experimental summary: This experiment reveals the core role of low-temperature granulation process and binder system design in the mechanical properties and functional stability of fertilizer particles. The microfluidic low-temperature process (10-20°C) forms a dense cross-linked structure of the PLGA core (porosity <5%) through the low interfacial tension and high shear uniformity of the silicone oil medium. The compressive strength of the particles is increased by 98% compared with the high-temperature emulsification method (Comparative Example 6). This difference is due to the fact that the low-temperature environment suppresses the accumulation of thermal stress during the solvent volatilization stage, avoiding the random curling of the PLGA molecular chains, thereby giving the core higher structural uniformity and deformation resistance.

[0236] The airflow suspension characteristics of the fluidized bed granulation process and the low temperature environment (<35°C) synergistically protect the activity of functional bacteria. Experimental data show that the survival rate of Bacillus amyloliquefaciens in Example 1 is 521% higher than that of traditional extrusion granulation (Comparative Example 7). This is attributed to the fact that airflow granulation avoids shear damage to the bacteria caused by mechanical extrusion, while the low temperature suppresses the metabolic inhibition of the PLGA prepolymer exothermicity during the granulation process. This process innovation breaks through the technical contradiction of "mechanical strength and bacterial activity" in the process of bacterial fertilizer granulation, and provides a feasible path for the large-scale production of functional fertilizers.

[0237] The binder system (sodium alginate-chitosan) achieves a dynamic match between disintegration rate and root metabolic activity through the dual effects of hydrogen bonding and ionic cross-linking. The experimental group of particles completely disintegrated in simulated rhizosphere fluid within 38 minutes, synchronizing with the release cycle of root secretions (such as organic acids and enzymes). This intelligent disintegration behavior allows the functional components (microbial agents, potassium silicate) to be precisely positioned in the effective action zone of the rhizosphere, avoiding the nutrient loss caused by premature disintegration or the utilization lag caused by delayed release in traditional fertilizers, and verifies the design logic of structure-function integration from the application level.

[0238] Test Example 5: Field application and soil improvement effect test

[0239] Purpose of the experiment:

[0240] Verify the effect of fertilizer on promoting the development of peanut root system (Comparative Example 8), improving the diversity of soil microorganisms (Comparative Example 9), and improving the soil acidification after long-term application (self-verification of Example 1).

[0241] Experimental steps:

[0242] Field trial design:

[0243] Treatment groups: Example 1, Comparative Example 8 (traditional NPK compound fertilizer), Comparative Example 9 (fertilizer without adding Trichoderma harzianum), and blank control (no fertilizer).

[0244] Test conditions:

[0245] Each treatment group was replicated three times and arranged in random blocks, with an area of 20 m 2 ;

[0246] Sowing density: 30cm×15cm, base fertilizer application rate 2.5kg / mu;

[0247] Conventional irrigation is used and no pesticides are sprayed during the entire growth period.

[0248] Root index determination:

[0249] Sampling time: flowering stage (60 days after sowing) and pod-setting stage (90 days after sowing).

[0250] Determination method:

[0251] Five peanut plants were randomly dug up from each plot and their roots were cleaned;

[0252] The root system was scanned and the total root length and root surface area were analyzed (WinRHIZO software);

[0253] The fresh weight of nodules (g / plant) was measured.

[0254] Soil microbial diversity detection:

[0255] Sampling: After harvest, rhizosphere soil (0-20 cm depth) was collected and samples were mixed in each plot.

[0256] Testing process:

[0257] DNA extraction and 16S rRNA sequencing (V3-V4 region);

[0258] Calculate Chao1 index (bacterial abundance) and Shannon index (diversity);

[0259] The relative abundance of Rhizobium and Actinobacteria was specifically analyzed.

[0260] Dynamic monitoring of soil pH:

[0261] Sampling frequency: before sowing, during flowering, and after harvest.

[0262] Detection method:

[0263] The soil suspension (water-soil ratio 2.5:1) was allowed to stand for 30 min and the pH was measured with a pH meter;

[0264] The pH variation range during the whole growth period was counted.

[0265] Experimental data:

[0266] Table 5 Field application and soil improvement test results

[0267]

[0268] Data Description:

[0269] Nodule development: The fresh weight of nodules in Example 1 increased by 124% compared with the traditional NPK fertilizer (Comparative Example 8), confirming the synergistic effect of the Rhizobium-Trichoderma harzianum symbiosis;

[0270] Microbial diversity: The Chao1 index of Example 1 increased by 100% compared with the blank group, and the relative abundance of rhizobia reached 12.3% (only 4.5% in the traditional NPK group);

[0271] Improvement of soil acidification: Example 1 increased the soil pH from an initial 5.1 to 6.3, while traditional NPK fertilizers aggravated the acidification (pH dropped to 5.1).

[0272] Experimental Summary: This experiment verified the comprehensive regulatory capacity of the bacteria-fertilizer-soil synergistic system in ecologically balanced fertilizers for crop growth and soil health. The symbiotic effect between Trichoderma harzianum and rhizobia significantly promoted root development through a metabolite exchange mechanism. The fresh weight of nodules in the experimental group increased by 124% compared to traditional NPK fertilizers. This is due to the efficient chelation of soil Fe by the siderophore secreted by Trichoderma harzianum. 3+ , providing essential metal elements for the active center of rhizobium nitrogenase (Fe-Mo cofactor). Simultaneously, the chitinase produced by the plant degrades the cell wall of pathogens, creating a synergistic effect of "growth promotion and disease resistance." Root scan data showed a 32% increase in root surface area during flowering, confirming the enhanced nutrient absorption efficiency of the symbiotic microbiome.

[0273] The slow release of potassium silicate and trace elements effectively blocked the soil acidification process. The soil pH in the experimental group increased from an initial 5.1 to 6.3, which was attributed to the continuous neutralization of magnesium carbonate in the PLGA core and the silicate colloidal buffer layer formed by the release of potassium silicate. This dynamic pH regulation not only inhibited aluminum toxicity (Al 3+ Hydrolysis is controlled by pH), and by activating soil phosphatase activity (optimum pH 6.0-7.0), the available phosphorus content is increased to 1.8 times that of the traditional fertilization group, solving the problem of nutrient immobilization caused by acidification at the soil microenvironment level.

[0274] The microbial community reconstruction data further revealed the cross-scale design logic. The relative abundance of rhizobia in the rhizosphere soil treated in Example 1 reached 12.3%, and the proportion of actinomycetes (key bacteria antagonizing pathogens) increased to 9.8%, which is directly related to the three-layer structure design of the fertilizer: the functional bacteria protected by the PLGA core preferentially colonize, the potassium silicate released in response to the mesoporous SiO2 shell enzyme selectively inhibits pathogenic fungi, and the silicon element released in stages by the thermosensitive hydrogel layer strengthens the niche competitive advantage of beneficial bacteria. This closed-loop system of "functional bacteria-slow-release nutrients-soil improvement" maximizes the ecological benefits of agricultural inputs.

[0275] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. An ecologically balanced fertilizer for increasing peanut production and resisting diseases, characterized in that: Calculated by weight percentage, it includes the following components: Core functional microspheres 55%-65%, from inside to outside include: PLGA core: comprising a copolymer of lactic acid and glycolic acid, wherein the particle size of the PLGA core is 80 μm-150 μm; Thermosensitive hydrogel middle layer: coated on the surface of the PLGA core, comprising a copolymer of N-isopropylacrylamide and acrylic acid, the thickness of the thermosensitive hydrogel middle layer is 15 μm-25 μm; Mesoporous SiO2 shell: coated on the surface of the thermosensitive hydrogel intermediate layer, formed by mesoporous SiO2 nanosheets with a pore size of 3.0nm-5.0nm modified by 3-aminopropyltriethoxysilane, with an amino modification density of 2.5μmol·m 2 -3.5 μmol·m 2 The shell contains 1.0×10 rhizobia. 8 CFU per gram shell up to 2.0 × 10 8 CFU per gram of shell, and methyl jasmonate; 8%-15% of hydroxyapatite nanorods, wherein the nanorods are 80nm-120nm in length, 15nm-25nm in diameter, and are surface-loaded with zinc, boron, and molybdenum; 4%-8% H2S slow-release precursor, which is L-cysteine loaded on a ZIF-8 metal-organic framework, where the drug loading of L-cysteine is 10%-15%; The binder is 8%-15%, and is composed of humic acid and sodium alginate in a mass ratio of 3:

1.

2. The ecologically balanced fertilizer for increasing peanut production and resisting disease according to claim 1, characterized in that: The molar ratio of lactic acid to glycolic acid is 75:25-80:20, the molecular weight is 12KDa-18KDa, magnesium carbonate with a particle size of 5μm-15μm, 1.0×10 6 CFU per gram of PLGA core to 5.0 × 10 6 CFU per gram of PLGA core, and L-malic acid.

3. The ecologically balanced fertilizer for increasing peanut production and resisting disease according to claim 1, characterized in that: The molar ratio of N-isopropylacrylamide to acrylic acid is 8:2 to 9:1, and the phase transition temperature of the copolymer is 24°C-26°C. The middle layer of the thermosensitive hydrogel is loaded with 5.0×10 7 CFU per gram of the middle layer to 1.0 × 10 8 CFU per gram of middle layer, and potassium silicate.

4. The ecologically balanced fertilizer for increasing peanut production and resisting disease according to claim 1, characterized in that: The thickness of the mesoporous SiO2 shell is 5 μm-10 μm.

5. The ecologically balanced fertilizer for increasing peanut production and resisting disease according to claim 1, characterized in that: The zinc, boron and molybdenum loadings of the hydroxyapatite nanorods are 4%-6%, 2%-4% and 1%-3% respectively, based on the total weight of the nanorods.

6. The ecologically balanced fertilizer for increasing peanut production and resisting disease according to claim 1, characterized in that: The molecular weight of humic acid in the binder is 1500Dal-2000Dal.

7. A method for preparing an ecologically balanced fertilizer for increasing peanut yield and resisting disease, characterized in that: The preparation method of the ecologically balanced fertilizer for increasing peanut production and resisting disease according to any one of claims 1 to 6 comprises the following steps: Preparation of the PLGA core: Lactic acid-glycolic acid copolymer, magnesium carbonate, Trichoderma harzianum chlamydospores, and L-malic acid were dissolved in dichloromethane to form an 8%-12% solution. The solution was passed through a microfluidic chip at a water-to-oil ratio of 1:4 to 1:6 at 10°C-20°C to form a water-in-oil emulsion. The solvent was evaporated for 12-24 hours to obtain the PLGA core. Thermosensitive hydrogel coating: N-isopropylacrylamide, acrylic acid, Bacillus amyloliquefaciens and potassium silicate were mixed to prepare thermosensitive hydrogel prepolymer solution. The PLGA core was immersed in the prepolymer solution. Under nitrogen protection, the temperature was measured at a wavelength of 360nm-370nm and an intensity of 8mW / cm 2 -12mW / cm 2 UV irradiation for 2-5 minutes to form an intermediate layer; Assembly of mesoporous SiO2 shell: Mesoporous SiO2 nanosheets were modified with 3-aminopropyltriethoxysilane and adsorbed with a rhizobium suspension at a pH of 7.0-8.0 for 12-24 hours to obtain rhizobium-loaded mesoporous SiO2. The mesoporous SiO2 was then coated onto the surface of the intermediate layer using a fluidized bed spraying process at an inlet air temperature of 30°C-40°C and an atomization pressure of 0.2MPa-0.4MPa to form a shell. Composite granulation: The core microspheres, hydroxyapatite nanorods, H2S slow-release precursor and binder are mixed and granules with a particle size of 2mm-4mm are prepared by a fluidized bed granulation process at an inlet air temperature of 40℃-50℃.

8. The method for preparing an ecologically balanced fertilizer for increasing peanut production and resisting disease according to claim 7, characterized in that: In the PLGA core preparation step, the oil phase is silicone oil with a viscosity of 50 MPa·s-100 MPa·s.

9. The method for preparing an ecologically balanced fertilizer for increasing peanut production and resisting disease according to claim 7, characterized in that: The OD600 value of the rhizobium suspension in the mesoporous SiO2 shell assembly step is 0.8-1.2.

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