Intelligent controlled-release fertilizer containing biological inducer and preparation method of intelligent controlled-release fertilizer

Abstract

The invention discloses an intelligent controlled-release fertilizer containing a biological inducer and a preparation method of the intelligent controlled-release fertilizer, and belongs to the technical field of agricultural fertilizers. The fertilizer constructs a'targeted nano delivery-three-level response synergy 'system, and comprises a targeted polylactic acid-glycolic acid copolymer nano carrier loaded with a biological inducer precursor, a pH-nutrient double-sensitive controlled-release coating and a fertilizer matrix. Through linkage response of rhizosphere pH signals, soil nutrient concentration and microbial esterase activation inducers, targeted aggregation and on-demand release of the inducers and nutrients are realized, and a dynamic supply closed loop is formed. The preparation method comprises the steps of nano-carrier synthesis modification, inducer loading, envelope preparation and forming. The problems that a traditional fertilizer is low in utilization rate, asynchronous in release and prone to leaching loss are solved, the nutrient utilization rate can be increased to 35%-50%, the crop disease occurrence rate can be reduced by 15%-20%, and the fertilizer is suitable for various crops and soil.

Description

Technical Field

[0001] This invention relates to the field of intelligent controlled-release fertilizers, specifically to an intelligent controlled-release fertilizer containing a bio-inducing agent and its preparation method. Background Technology

[0002] With the increasing demand for sustainable development in modern agriculture, traditional chemical fertilizers, while increasing crop yields, have also led to soil degradation and environmental pollution. Existing controlled-release fertilizers typically control nutrient release only through physical or chemical methods, failing to effectively respond to crop needs and resulting in a mismatch between nutrient release and actual demand. Furthermore, the bio-inducers in traditional fertilizers are mostly released passively, failing to synchronize with crop growth and microbial activity, thus limiting their effectiveness. Therefore, developing a fertilizer system that can intelligently control nutrient release and dynamically regulate the release of bio-inducers has become crucial for improving fertilizer efficiency and promoting green agriculture.

[0003] This invention proposes an intelligent controlled-release fertilizer based on "rhizosphere targeted delivery" and "three-level response mechanism," which can accurately release nutrients and bio-inducers, solve the drawbacks of traditional fertilizers, improve crop growth and stress resistance, and reduce environmental pollution. Summary of the Invention

[0004] To address the aforementioned problems, this invention proposes a smart controlled-release fertilizer containing a bio-inducing agent and its preparation method. This fertilizer can precisely release nutrients according to crop needs, and achieves intelligent release of the bio-inducing agent through a rhizosphere-targeted delivery system and a three-level response mechanism, effectively improving fertilizer utilization efficiency, promoting crop growth and stress resistance, while reducing negative environmental impacts. This fertilizer exhibits excellent performance in nutrient release synchronization, crop growth promotion, and environmental adaptability, meeting the demands of modern agriculture for efficient and green fertilizers.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A smart controlled-release fertilizer containing a bio-inducing agent, said fertilizer being prepared from the following raw materials in parts by weight: 50-80 parts fertilizer matrix, 5-15 parts targeted nanocarrier loaded with biological inducer precursor, and 10-25 parts pH-nutrient dual-sensitive controlled-release coating material; In this embodiment, the targeted nanocarrier loaded with the bio-inducing agent precursor has a mass ratio of 8%-20% for the bio-inducing agent precursor; the targeted nanocarrier is polylactic-co-glycolic acid (PLGA) nanoparticles with a surface modified with crop rhizosphere-specific ligands, and the particle size of the PLGA nanoparticles is 10-100 nm; the pH-nutrient dual-sensitive controlled-release coating is made of polyacrylic acid and polyβ-hydroxybutyrate blended together, with a mass ratio of polyacrylic acid to polyβ-hydroxybutyrate of 3:7-7:3; the bio-inducing agent precursor is a microbial esterase-degraded derivative, and the intelligent controlled-release fertilizer achieves on-demand release of inducers and nutrients through a three-level response mechanism, which includes: a primary response to the rhizosphere pH signal under crop nutrient stress, a secondary response to the soil available nutrient concentration threshold, and a tertiary response to the activation effect of the bio-inducing agent precursor by esterases secreted by beneficial rhizosphere bacteria.

[0006] Preferably, the crop rhizosphere-specific ligand is selected from one or more of the following: root hair cell surface glycoprotein receptors, root-secreted flavonoids, and specific antibodies against plant root surface glycoproteins.

[0007] Preferably, the rhizosphere pH signal range of the first-order response is 5.0-5.5 or 7.5-8.0; the soil available nitrogen concentration threshold of the second-order response is 30-80 mg / kg, and the soil available phosphorus concentration threshold is 10-30 mg / kg.

[0008] Preferably, the biological inducer precursor is one or more of methyl jasmonate, indoleacetic acid, flavonoid derivatives, and gibberellin ethyl ester.

[0009] Preferably, the molar ratio of lactic acid to glycolic acid in the polylactic acid-glycolic acid copolymer nanoparticles is 50:50-85:15.

[0010] Preferably, the fertilizer matrix includes two or more of a nitrogen source, a phosphorus source, and a potassium source. The nitrogen source is selected from one or more of urea, ammonium nitrate, and amino acid salts. The phosphorus source is selected from one or more of potassium dihydrogen phosphate, superphosphate, and ammonium phosphate. The potassium source is selected from one or more of potassium chloride, potassium sulfate, and potassium nitrate.

[0011] Preferably, the loading of the targeted nanocarrier is 5wt%-15wt%, and the thickness of the pH-nutrient dual-sensitive controlled-release membrane is 50-200 μm.

[0012] Preferably, the preparation method of the intelligent controlled-release fertilizer containing a bio-inducing agent includes the following specific preparation steps: S1. Dissolve polylactic acid-glycolic acid copolymer in dichloromethane or ethyl acetate, add 1wt%-5wt% polyvinyl alcohol or polyethylene glycol dispersant, emulsify at 25-35℃ and 800-1200 rpm for 30-60 min, and then stir and volatilize at 30-40℃ for 4-8 h to prepare blank polylactic acid-glycolic acid copolymer nanoparticles; S2. The crop rhizosphere-specific ligands are reacted with the carboxyl groups on the surface of blank polylactic acid-glycolic acid copolymer nanoparticles through a composite coupling agent at 25-40℃ for 2-6 h to obtain targeted nanocarriers. S3. Dissolve the biological inducer precursor in ethanol or acetone, add the targeted nanocarrier, and stir at 500-800 rpm at 20-30℃ for 1-3 h to adsorb. Then centrifuge at 8000-12000 rpm for 15-30 min to obtain the targeted nanocarrier loaded with the inducer precursor. S4. Mix polyacrylic acid and polyβ-hydroxybutyrate in a mass ratio of 3:7-7:3, add 3%-8% of tributyl citrate plasticizer in the total mass of the mixture, and melt-blend at 160-180℃ for 20-40 min to obtain a pH-nutrient dual-sensitive controlled-release coating material. S5. Mix the fertilizer matrix with the targeted nanocarrier carrying the inducer precursor evenly, and use a spray coating method to coat the surface of the mixture with a pH-nutrient dual-sensitive controlled-release coating material. Control the inlet air temperature at 60-90℃, the outlet air temperature at 30-50℃, and the spray pressure at 0.3-0.8MPa. After drying, the intelligent controlled-release fertilizer containing the biological inducer is obtained.

[0013] The beneficial effects of this invention are: This invention utilizes a "targeted nanodelivery-three-level response synergy" system. Through a PLGA nanocarrier with surface-modified ligands, it precisely delivers the inducer precursor to the rhizosphere. Combined with a pH- and nutrient-sensitive dual-sensitivity coating for on-demand release, nutrient utilization is improved by 35%-50% compared to traditional fertilizers. The activated inducer achieves a synergistic effect of "growth promotion and stress resistance," increasing crop yield by 20%-25% and reducing disease incidence by 15%-20%. Both the carrier and the coating are biodegradable, leaving no environmental residue. The modular design adapts to different crops and soils, and the mature process facilitates large-scale production, precisely addressing the problems of asynchronous supply and demand, limited functionality, and pollution associated with traditional fertilizers. Attached Figure Description

[0014] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0015] Figure 1 This is a line graph showing the cumulative release amount of different samples of the present invention over time; Figure 2 This is a comparison chart of the yield increase rate and disaster incidence rate of different samples in this invention. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0017] Example 1: This embodiment 1 describes a smart controlled-release fertilizer for corn containing a bio-inducing agent, prepared from the following raw materials in parts by weight: Fertilizer matrix: 40 parts urea, 20 parts potassium dihydrogen phosphate, 10 parts potassium chloride; Targeted nanocarrier loaded with biological inducer precursor: 10 parts PLGA nanocarrier loaded with naringin; pH-nutrient dual-sensitive controlled-release coating material: 20 parts polyacrylic acid: polyβ-hydroxybutyrate = 5:5. This embodiment describes a method for preparing a smart controlled-release fertilizer containing a bio-inducing agent. The specific preparation steps are as follows: S1. Dissolve PLGA in dichloromethane, add 3wt% polyvinyl alcohol, emulsify at 28℃ and 1000 rpm for 45 min, stir and volatilize at 35℃ for 6 h to obtain blank polylactic acid-glycolic acid copolymer nanoparticles. S2. Disperse blank PLGA nanoparticles in PBS buffer at pH 7.4, add 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) / N-hydroxysuccinimide (NHS) composite coupling agent at a molar ratio of 1:1, and stir to activate for 30 min; then add root-secreting flavonoid-specific antibody, and react at 30℃ with shaking for 4 h. After the reaction, centrifuge and wash 3 times to obtain the targeted nanocarrier. S3. Naringin was dissolved in anhydrous ethanol and added dropwise to an aqueous dispersion containing the targeted nanocarrier. The mixture was stirred at 600 rpm at 25°C for 2 h to adsorb the anaringin. Then, it was centrifuged at 10,000 rpm for 20 min, the supernatant was discarded, and the precipitate was dried under vacuum to obtain the targeted nanocarrier loaded with naringin. S4. Polyacrylic acid and polyβ-hydroxybutyrate are mixed at a mass ratio of 5:5. Tributyl citrate plasticizer accounting for 5% of the total mass of the mixture is added. The mixture is melt-blended at 170°C for 30 min and then extruded and granulated to obtain a pH-nutrient dual-sensitive controlled-release coating material. S5. Mix the fertilizer matrix with the targeted nanocarrier loaded with the inducer precursor evenly, and use a spray coating method to coat the surface of the mixture with a pH-nutrient dual-sensitive controlled-release coating material. Control the inlet air temperature to 75℃, the outlet air temperature to 40℃, and the spray pressure to 0.5 MPa. After coating, dry the mixture at 60℃ for 2 hours to obtain a smart controlled-release fertilizer containing a biological inducer.

[0018] Example 2: This Example 2 describes a smart controlled-release fertilizer for tomatoes containing a bio-inducing agent. The fertilizer is prepared from the following raw materials in parts by weight: Fertilizer matrix: 30 parts urea, 25 parts superphosphate, 10 parts potassium sulfate; Targeted nanocarrier loaded with biological inducer precursor: 8 parts PLGA nanocarrier loaded with naringin; pH-nutrient dual-sensitive controlled-release coating material: 22 parts polyacrylic acid: polyβ-hydroxybutyrate = 4:6. The preparation method of the intelligent controlled-release fertilizer containing a bio-inducer in this embodiment is the same as that in Example 1, except that the ratio in step S4 is adjusted to 4:6.

[0019] Example 3: This embodiment 2 presents a soybean-specific intelligent controlled-release fertilizer containing a bio-inducing agent, prepared from the following raw materials in parts by weight: Fertilizer matrix: 25 parts urea, 30 parts potassium dihydrogen phosphate, 15 parts potassium chloride; Targeted nanocarrier loaded with biological inducer precursor: 12 parts PLGA nanocarrier loaded with naringin; pH-nutrient dual-sensitive controlled-release coating material: 22 parts polyacrylic acid: polyβ-hydroxybutyrate = 6:4. The preparation method of the intelligent controlled-release fertilizer containing a bio-inducer in this embodiment is the same as that in Example 1, except that the ratio in step S4 is adjusted to 6:4.

[0020] Comparative Example 1: The fertilizer in Comparative Example 1 was prepared from the following raw materials in parts by weight: Fertilizer matrix: 40 parts urea, 20 parts potassium dihydrogen phosphate, 10 parts potassium chloride; Targeted nanocarrier loaded with biological inducer precursor: 0 parts PLGA nanocarrier loaded with naringin; pH-nutrient dual-sensitive controlled-release coating material: 20 parts polyacrylic acid: polyβ-hydroxybutyrate = 5:5. In this comparative example, the fertilizer was prepared using the same method as in Example 1, by directly mixing naringin with the fertilizer matrix without adding any targeted nanocarriers.

[0021] Comparative Example 2: The fertilizer in Comparative Example 2 was prepared from the following raw materials in parts by weight: Fertilizer matrix: 40 parts urea, 20 parts potassium dihydrogen phosphate, 10 parts potassium chloride; Targeted nanocarrier loaded with biological inducer precursor: 10 parts PLGA nanocarrier loaded with naringin; pH-nutrient dual-sensitive controlled-release coating material: 20 parts poly-β-hydroxybutyrate. The fertilizer preparation method in this comparative example is the same as in Example 1, except that the coating material is replaced with a single poly-β-hydroxybutyrate.

[0022] Comparative Example 3: The fertilizer in Comparative Example 3 was prepared from the following raw materials in parts by weight: Fertilizer matrix: 40 parts urea, 20 parts potassium dihydrogen phosphate, 10 parts potassium chloride; Targeted nanocarrier loaded with biological inducer precursor: 10 parts PLGA nanocarrier; pH-nutrient dual-sensitive controlled-release coating material: 20 parts polyacrylic acid: polyβ-hydroxybutyrate = 5:5. The fertilizer in this comparative example was prepared using the same method as in Example 1, without the addition of the bio-inducing agent naringin.

[0023] Comparative Example 4: Commercially available corn-specific coated controlled-release fertilizer with a nitrogen, phosphorus, and potassium ratio of 28:10:12.

[0024] Performance testing 1. Targeted delivery efficiency test 0.1 g of sodium fluorescein was dissolved in 10 mL of ethanol, and 1 g of PLGA blank nanocarrier with surface-modified specific ligands was added. The mixture was stirred at 25 °C and 600 rpm for 2 h to allow the fluorescent probe to adsorb onto the nanocarrier. Then, the mixture was centrifuged at 10000 rpm for 20 min, and the precipitate was collected to obtain the fluorescently labeled targeting nanocarrier. Next, the fluorescently labeled nanocarrier was mixed with soil and applied around the roots of potted crops. Corn, tomato, and soybean seeds were sown in pots of uniform size. Seedling management was initiated when the seedlings reached 3 leaves and 1 heart, and the labeled targeting nanocarrier was applied. After 30 days of cultivation, 10 g each of rhizosphere and non-rhizosphere soil were collected.

[0025] After adding 20 mL of deionized water to the collected soil samples, ultrasonic extraction was performed for 30 min, followed by centrifugation. The supernatant was collected, and the fluorescence intensity was measured using a fluorescence spectrophotometer (excitation wavelength 490 nm, emission wavelength 520 nm). The ratio of fluorescence intensity between rhizosphere soil and non-rhizosphere soil was calculated, and the rhizosphere enrichment rate was finally obtained. When the ratio of fluorescence intensity between rhizosphere soil and non-rhizosphere soil was ≥3.5, it had a precise enrichment effect.

[0026] Table 1. Data on the rhizosphere enrichment rate of targeted nanocarriers in different samples.

[0027] The rhizosphere enrichment rates of Examples 1-3 reached 4.2, 3.8 and 4.0 respectively, all meeting the criterion of ≥3.5, which confirms that crop rhizosphere-specific ligand modification can achieve precise enrichment of nanocarriers into the rhizosphere, providing a core guarantee for targeted nutrient supply.

[0028] 2. pH-Nutrient Dual-Sensitive Controlled-Release Performance Test The fertilizer sample was crushed and sieved through a 2 mm sieve. 5 g of the sample was weighed and placed in dialysis bags. The surface of the dialysis bags was washed with deionized water and the bags were sealed tightly. Two buffer solutions were prepared in 500 mL: an acetate-sodium acetate buffer solution with pH=5.5 and a potassium dihydrogen phosphate-disodium hydrogen phosphate buffer solution with pH=7.0. The buffer solutions were poured into 1000 mL Erlenmeyer flasks, and the dialysis bags containing the fertilizer samples were completely immersed in the buffer solutions and the flasks were sealed. The sealed conical flask was placed in a constant-temperature water bath shaker and shaken continuously at 30℃ and 150 rpm. At 1, 7, 14, and 28 days of shaking, 5 mL of the extract was taken, and 5 mL of the corresponding buffer solution was added simultaneously to maintain a constant volume. The concentrations of nitrogen, phosphorus, and potassium in the extract were measured using a UV spectrophotometer. The cumulative nutrient release was calculated using the following formula:

[0029]

[0030] Table 2. Cumulative nutrient release data (%) of different samples under two pH conditions

[0031] Examples 1-3 showed a cumulative nutrient release of 85%-90% in the rhizosphere acidic environment over 28 days, compared to only 30%-35% in the non-rhizosphere neutral environment, indicating a significant difference in release response. In contrast, Comparative Example 2 showed a release difference of less than 10% between the two pH environments, fully verifying that the pH-nutrient dual-sensitive coating material of this invention can achieve on-demand nutrient release and effectively reduce nutrient loss in non-rhizosphere environments.

[0032] 3. Crop application effect test Experimental Materials and Grouping: The crop varieties used in the experiment were the same as those used in the targeted delivery efficiency test. The test soil was alluvial soil with an organic matter content of 12.5 g / kg, available nitrogen of 86.3 mg / kg, available phosphorus of 15.2 mg / kg, and available potassium of 98.7 mg / kg. The experiment was divided into 8 treatment groups: Examples 1-3, Comparative Examples 1-4, and a blank control group (no fertilizer applied). Each group was replicated in 3 pots.

[0033] Fertilizer application and cultivation management: Based on a pure nitrogen dosage of 1.5 g / pot, each treatment group was given the corresponding amount of fertilizer as a base fertilizer, applied once to a depth of 10 cm in the soil. Corn, tomato, and soybean were each given their respective specialized fertilizers; Comparative Example 4 was used only for the corn experiment. All pots were placed in a smart greenhouse, with the temperature maintained at 25±2℃, light duration at 16 h / day, and relative humidity controlled between 60% and 70%. Watering was performed using a weighing method to maintain soil moisture content at 70% of field capacity.

[0034] Indicator Measurement and Calculation: After crop harvest, the biomass of the aboveground and underground parts of the plant is measured separately. After crushing, the contents of total nitrogen, total phosphorus, and total potassium are measured. The total nutrient absorption and nutrient utilization rate are calculated. The yield increase rate is calculated by measuring the yield of corn kernels, the total fruit yield per tomato plant, and the yield of soybean kernels. The disease incidence rate is calculated by investigating the occurrence of crop diseases once a week during the growing season.

[0035] Table 3. Test data on the application effects of different crop samples

[0036] The nutrient utilization rates of Examples 1-3 were increased by 13.1%-15.7%, 9.8%-12.4%, 7.5%-10.1%, and 17.0%-20.0% respectively compared with Comparative Examples 1-4; the yield increase rate was also significantly higher than that of each comparative example; and the disease incidence rate was reduced by 5.4%-14.6% compared with the comparative examples.

[0037] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A smart controlled release fertilizer containing a bio-inducer, characterized in that, The fertilizer is prepared from the following raw materials by weight parts: 5-15 parts of the targeted nanocarrier loaded with a biological inducer precursor, and 10-25 parts of a pH-nutrient dual-sensitive controlled-release coating material; The targeted nanocarrier loaded with the biological inducer precursor has a mass fraction of the biological inducer precursor of 8%-20%; the targeted nanocarrier is a polylactic acid-glycolic acid copolymer nanoparticle with a crop rhizosphere specific ligand on the surface, the polylactic acid-glycolic acid copolymer nanoparticle has a particle size of 10-100 nm; the pH-nutrient dual-sensitive controlled-release coating is made of polyacrylic acid and poly-beta-hydroxybutyric acid ester, and the mass ratio of the polyacrylic acid to the poly-beta-hydroxybutyric acid ester is 3:7-7:3; the biological inducer precursor is a microbial esterase degradation type derivative, and the intelligent controlled-release fertilizer realizes on-demand release of the inducer and the nutrient through a three-level response mechanism, the three-level response mechanism includes a primary response to a rhizosphere pH signal under crop nutrient stress, a secondary response to a soil available nutrient concentration threshold, and a tertiary response to an activation effect of an esterase secreted by a rhizosphere beneficial bacteria on the biological inducer precursor.

2. The intelligent controlled release fertilizer containing a biological elicitor according to claim 1, characterized in that, The crop rhizosphere specific ligand is selected from one or more of a root hair cell surface glycoprotein receptor, a root system secreted flavonoid, and a specific antibody of a plant root system surface specific glycoprotein.

3. The intelligent controlled release fertilizer containing a biological elicitor according to claim 1, characterized in that, The rhizosphere pH signal interval of the primary response is 5.0-5.5 or 7.5-8.0; the soil available nitrogen concentration threshold of the secondary response is 30-80 mg / kg, and the soil available phosphorus concentration threshold is 10-30 mg / kg.

4. The bio-elicitor containing smart controlled release fertilizer according to claim 1, wherein, The biological inducer precursor is one or more of methyl jasmonate, indole acetic ester, flavonoid derivatives, and gibberellin ethyl ester.

5. The bio-elicitor containing smart controlled release fertilizer according to claim 1, wherein, The polylactic acid-glycolic acid copolymer nanoparticle has a molar ratio of lactic acid to glycolic acid of 50:50-85:

15.

6. The bio-elicitor containing smart controlled release fertilizer according to claim 1, wherein, The fertilizer base includes two or more of a nitrogen source, a phosphorus source, and a potassium source, the nitrogen source is selected from one or more of urea, ammonium nitrate, and amino acid salt, the phosphorus source is selected from one or more of potassium dihydrogen phosphate, superphosphate, and ammonium phosphate, and the potassium source is selected from one or more of potassium chloride, potassium sulfate, and potassium nitrate.

7. The bio-elicitor containing smart controlled release fertilizer according to claim 1, wherein, The loading amount of the targeted nanocarrier is 5wt%-15wt%, and the thickness of the pH-nutrient dual-sensitive controlled-release coating is 50-200 μm.

8. A process for the preparation of a smart controlled release fertilizer containing a bio-elicitor, the fertilizer being as claimed in any one of claims 1 to 7, characterized in that, The specific preparation steps are as follows: S1, dissolve the polylactic acid-glycolic acid copolymer in dichloromethane or ethyl acetate, add a polyvinyl alcohol or polyethylene glycol dispersant with a concentration of 1wt%-5wt%, emulsify at a speed of 800-1200 rpm for 30-60 min at 25-35℃, and then volatilize at 30-40℃ for 4-8 h to prepare the blank polylactic acid-glycolic acid copolymer nanoparticle; S2, react the crop rhizosphere specific ligand with the carboxyl group on the surface of the blank polylactic acid-glycolic acid copolymer nanoparticle through complex coupling agent, and react for 2-6 h at 25-40℃ to obtain the targeted nanocarrier; S3, dissolving the biological inducer precursor in ethanol or acetone, adding the targeted nano-carrier, stirring and adsorbing at 500-800 rpm for 1-3 h at 20-30℃, then centrifuging at 8000-12000 rpm for 15-30 min to obtain the targeted nano-carrier loaded with the inducer precursor; S4, mixing polyacrylic acid and poly-β-hydroxybutyric acid at a mass ratio of 3:7-7:3, adding 3%-8% of the total mass of the mixture tributyl citrate plasticizer, and melt blending at 160-180℃ for 20-40 min to obtain the pH-nutrient dual-sensitive controlled-release coating material; S5, uniformly mixing the fertilizer matrix and the targeted nano-carrier loaded with the inducer precursor, using the spray coating method to coat the pH-nutrient dual-sensitive controlled-release coating material on the surface of the mixture, controlling the inlet air temperature of 60-90℃, the outlet air temperature of 30-50℃, and the spraying pressure of 0.3-0.8 MPa, and drying to obtain the intelligent controlled-release fertilizer containing biological inducer.

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