Compound formula of silverweed cinquefoil root flowering fertilizer and application thereof

Abstract

The invention discloses a silverweed cinquefoil root flowering fertilizer composite formula and application thereof, and relates to the technical field of compound fertilizers, the silverweed cinquefoil root flowering fertilizer composite formula comprises, by weight, 15-25 parts of a nano carrier, 28-44 parts of an organic raw material, 7-15 parts of an inorganic raw material, 8-12 parts of biological bacteria, 0.2-0.3 part of a biological regulator, and 6-11 parts of a trace element composition; wherein the nano carrier is prepared from 12 to 20 parts of nano diatomite and 3 to 5 parts of nano hydroxyapatite; the nano diatomite is obtained by sequentially stirring a 2mol / L NaOH solution at the temperature of 60 DEG C for 2 hours, adjusting the pH value to 6.0 by a 1mol / L HCl solution and drying at the temperature of 105 DEG C; the specific surface area of the nano diatomite is greater than or equal to 85 m < 2 > / g The application has the effects of meeting the nutrient and physiological requirements in the key flowering period of the potentilla anserine and improving the flowering rate and the fruit setting rate of the potentilla anserine through nano-carrier modification and functional component optimization.

Description

Technical Field

[0001] This application relates to the field of compound fertilizer technology, and in particular to a compound fertilizer formula for fern root flowering and its application. Background Technology

[0002] *Fern root* (also known as *Fern rhizome*) is native to many provinces in China. It grows on riverbanks, roadsides, hillsides, grasslands, and meadows. This species has a wide distribution, spanning the temperate zones of the Northern Hemisphere across Eurasia and America, as well as Chile in South America, New Zealand in Oceania, and Tasmania. Its roots are enlarged and rich in starch, and are commercially known as "fern root" or "ginseng fruit." It is used to treat anemia and malnutrition, and can also be used in sweet foods and for brewing. The roots contain tannins, which can be used to extract tannin, and it can also be used medicinally as an astringent. The stems and leaves can be used to extract a yellow dye. It is also a source of nectar for bees and as fodder. *Fern root* prefers moist conditions and is highly adaptable. Originally wild, it is now widely cultivated. *Fern root* has no special requirements for soil; it can be planted in both fertile and poor soil, but fertile, loose soil is best.

[0003] Chinese patent application CN106810381A discloses a special fertilizer for fern root and its preparation method. The special fertilizer for fern root is made from the following raw materials in the following weight proportions: 25-40 parts manure, 8-19 parts humic acid, 20-35 parts soybean meal, 8-15 parts distiller's grains, 4-10 parts gelatin, 5-10 parts biological bacteria, 6-12 parts maifanite, 8-10 parts diatomaceous earth, 5-14 parts vermiculite, 1-3 parts borax, 2-6 parts urea, 1-3 parts monoammonium phosphate, 1-5 parts ammonium bicarbonate, 2-5 parts potassium chloride, 2-4 parts potassium sulfate, 1-5 parts calcium oxide, 1-6 parts zinc sulfate, 1-4 parts ammonium molybdate, 2-5 parts boric acid, 0.2-0.5 parts matrine, 0.3-0.6 parts gibberellin, 5-8 parts ethanol, and 35-60 parts water.

[0004] However, the special fertilizer for fern root and its preparation method have problems with the lack of synergy and targeting of functional components. In the mixture of biological bacteria, gibberellin and other trace elements used, the interaction will cause some biological bacteria to be inhibited by gibberellin or high concentration of inorganic salts, thereby affecting the release of fertilizer function and the stable flowering and growth of fern root. This needs to be improved. Summary of the Invention

[0005] In view of this, the first objective of this application is to provide a compound fertilizer formula for *Fernonia acutissima* flowering, to meet the nutrient and physiological needs of *Fernonia acutissima* during its critical flowering period, and to improve the flowering rate and fruit setting rate of *Fernonia acutissima* through nanocarrier modification and functional component optimization. The specific scheme is as follows: A compound fertilizer formula for flowering fern root includes, by weight, 15-25 parts of nano-carrier, 28-44 parts of organic raw materials, 7-15 parts of inorganic raw materials, 8-12 parts of biological bacteria, 0.2-0.3 parts of biological regulator, and 6-11 parts of a trace element composition; wherein: The nanocarrier is composed of 12-20 parts of nano-diatomite and 3-5 parts of nano-hydroxyapatite; the nano-diatomite is obtained by sequentially stirring with 2 mol / L NaOH solution at 60℃ for 2 h and adjusting the pH to 6.0 with 1 mol / L HCl solution, and then drying at 105℃; the specific surface area of ​​the nano-diatomite is ≥85 m² / g. 2 / g.

[0006] Preferably, the preparation method of the nanocarrier includes step ① mixing nano-diatomite and nano-hydroxyapatite, adding 0.5% by mass of silane coupling agent KH-550, and obtaining a modified composite carrier by stirring; step ② the modified composite carrier has a particle size of 50-100 nm, and is dispersed in anhydrous ethanol, adding 1% by mass of silane coupling agent KH-792, and refluxed at 70±0.5℃ for 4 h to obtain an aminated composite carrier; step ③ the aminated composite carrier is added to a 2% by mass maleic anhydride ethanol solution, and stirred at 65±0.5℃ for 6 h to obtain an amino-carboxyl bifunctional carrier with a surface amino density ≥2.5 mmol / g and a carboxyl density ≥1.8 mmol / g.

[0007] Preferably, the amino-carboxyl bifunctional carrier further includes a core-shell coating treatment; the core-shell coating treatment includes step ① mixing N-isopropylacrylamide and methacrylic acid at a mass ratio of 3-3.2:2, adding 0.5% ammonium persulfate as an initiator, and controlling the temperature at 60°C to obtain a shell polymer emulsion; step ② immersing the amino-carboxyl bifunctional carrier in the shell polymer emulsion, and spray drying the mixture to obtain a core-shell coated carrier.

[0008] Preferably, the inlet air temperature of the spray drying process is 120°C and the outlet air temperature is 50°C; the shell membrane thickness of the core-shell coated carrier is 5-8 μm.

[0009] Preferably, the organic raw material consists of 15-22 parts by weight of fermented soybean meal, 8-12 parts by weight of distiller's grains, and 5-10 parts by weight of humic acid.

[0010] Preferably, the inorganic raw material consists of 2-4 parts by weight of ammonium nitrate, 3-6 parts by weight of superphosphate, and 2-5 parts by weight of potassium chloride.

[0011] Preferably, the microorganisms consist of 4-6 parts by weight of Bacillus spp. gelatinosa, 2-3 parts by weight of Pseudomonas phosphate-solubilizingis, and 2-3 parts by weight of yeast, and the viable count is ≥2×10⁻⁶. 9 CFU / g.

[0012] Preferably, the bioregulator is composed of 0.1-0.15 parts by weight of zeatin, 0.05-0.1 parts by weight of triacontanol and 0.05 parts by weight of salicylic acid.

[0013] Preferably, the trace element composition consists of 2-3 parts by weight of borax, 1.5-2 parts by weight of zinc sulfate, 1-1.5 parts by weight of ammonium molybdate, 0.5-1 parts by weight of copper sulfate, 0.5-1 parts by weight of manganese sulfate, and 0.5-2 parts by weight of chelated iron.

[0014] The second objective of this invention is to provide an application of a compound fertilizer formula for flowering fern, including the use of a compound fertilizer formula for flowering fern as described above, and its application for fertilization during the flowering period of fern.

[0015] As can be seen from the above scheme, this application provides a compound fertilizer formula for *Pteris vittata* flowering and its application. When applied to *Pteris vittata* during its flowering period, this compound fertilizer formula directly promotes flower bud differentiation and floral organ development through biological regulators. Combined with the continuous nutrients provided by organic raw materials and the efficient adsorption and slow-release effect of nanocarriers, it provides sufficient and stable nutrition for flower bud formation, significantly increasing the number and uniformity of flowers. Simultaneously, trace elements promote pollen germination and pollen tube elongation, solving the problem of low fruit set due to poor pollination. Biological bacteria activate soil nutrients and improve root absorption capacity. Combined with the precise nutrient release of the shell-core coated carrier, it provides essential nutrients for ovary development after pollination during the critical flowering stage, reducing flower and fruit drop. Furthermore, the dual slow-release system formed by the amino-carboxyl dual-group carrier and the shell-core coated structure effectively avoids nutrient imbalance in plants caused by the sudden release of inorganic nutrients. This synergistic effect of biological bacteria improves the soil microenvironment, enhances the stress resistance of *Pteris vittata*, and reduces the impact of adverse environmental conditions during flowering on fruit set, thereby effectively improving the flowering and fruit set rates of *Pteris vittata*. Detailed Implementation

[0016] The technical solutions described below in conjunction with the embodiments of this application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0017] It should be mentioned that the fermented soybean meal in this application embodiment has a protein content of ≥45%, an alcohol content of ≤5%, a fulvic acid content of humic acid of ≥60%, a nitrogen content of ammonium nitrate of ≥33%, an available phosphorus content of superphosphate of ≥16%, a potassium content of potassium chloride of ≥60%, a boron content of borax of ≥11%, a zinc content of zinc sulfate of ≥22%, a molybdenum content of ammonium molybdate of ≥54%, a copper content of copper sulfate of ≥25%, a manganese content of manganese sulfate of ≥26%, and an EDTA-Fe content of chelated iron of ≥99%.

[0018] Of course, other embodiments obtained by adjusting the content of the main components in different components and the weight parts of the components in the embodiments of this application are also within the scope of protection of this application, and will not be elaborated here.

[0019] The following is a detailed description of a compound fertilizer formula for flowering fern root and its application, based on this application.

[0020] A compound fertilizer formula for flowering fern root includes 15-25 parts by weight of nanocarrier, 28-44 parts by weight of organic raw materials, 7-15 parts by weight of inorganic raw materials, 8-12 parts by weight of biological bacteria, 0.2-0.3 parts by weight of biological regulator, and 6-11 parts by weight of trace element composition.

[0021] It should be noted that the organic raw materials in this application embodiment consist of 15-22 parts by weight of fermented soybean meal, 8-12 parts by weight of distiller's grains, and 5-10 parts by weight of humic acid. The inorganic raw materials consist of 2-4 parts by weight of ammonium nitrate, 3-6 parts by weight of superphosphate, and 2-5 parts by weight of potassium chloride. The microbial organisms consist of 4-6 parts by weight of Bacillus mucilaginosus, 2-3 parts by weight of Pseudomonas phosphate-solubilizing, and 2-3 parts by weight of yeast, with a viable count ≥ 2 × 10⁻⁶. 9 CFU / g. The bioregulator consists of 0.1-0.15 parts by weight of zeatin, 0.05-0.1 parts by weight of triacontanol, and 0.05 parts by weight of salicylic acid. The trace element composition consists of 2-3 parts by weight of borax, 1.5-2 parts by weight of zinc sulfate, 1-1.5 parts by weight of ammonium molybdate, 0.5-1 parts by weight of copper sulfate, 0.5-1 parts by weight of manganese sulfate, and 0.5-2 parts by weight of chelated iron.

[0022] Meanwhile, to ensure precise regional loading and avoid interference between components such as cationic trace elements and anionic bacteria, the nanocarrier used in this embodiment is composed of 12-20 parts of nano-diatomite and 3-5 parts of nano-hydroxyapatite. The nano-diatomite is obtained by sequentially stirring in a 2 mol / L NaOH solution at 60°C for 2 hours, adjusting the pH to 6.0 with a 1 mol / L HCl solution, and then drying at 105°C. The specific surface area of ​​the nano-diatomite is ≥85 m² / g. 2 / g.

[0023] It should be mentioned that the preparation method of the nanocarrier includes step ① mixing nano-diatomite and nano-hydroxyapatite, adding 0.5% by mass of silane coupling agent KH-550, and obtaining a modified composite carrier by stirring; step ② the modified composite carrier has a particle size of 50-100 nm, and is dispersed in anhydrous ethanol, adding 1% by mass of silane coupling agent KH-792, and refluxed at 70±0.5℃ for 4 h to obtain an aminated composite carrier; step ③ the aminated composite carrier is added to a 2% by mass maleic anhydride ethanol solution, and stirred at 65±0.5℃ for 6 h to obtain an amino-carboxyl bifunctional carrier with a surface amino density ≥2.5 mmol / g and a carboxyl density ≥1.8 mmol / g.

[0024] Furthermore, to further improve the matching effect of flowering period of *Pteris vittata* and avoid the problems of ineffective nutrient release under low temperature and low light and rapid nutrient release under high temperature and high humidity, the amino-carboxyl bifunctional carrier in this application embodiment also includes a core-shell coating treatment. The core-shell coating treatment includes step ① mixing N-isopropylacrylamide and methacrylic acid at a mass ratio of 3-3.2:2, adding 0.5% ammonium persulfate as an initiator, and controlling the temperature at 60°C to obtain a shell polymer emulsion; step ② immersing the amino-carboxyl bifunctional carrier in the shell polymer emulsion, and spray drying at an inlet air temperature of 120°C and an outlet air temperature of 50°C to obtain a core-shell coated carrier with a shell membrane thickness of 5-8 μm.

[0025] The application of a compound fertilizer formula for flowering fern includes using the compound fertilizer formula for flowering fern as described above and applying it to the flowering period of fern.

[0026] Example 1

[0027] A compound fertilizer formula for flowering fern root includes 15 parts by weight of nanocarrier, 28 parts by weight of organic raw materials, 7 parts by weight of inorganic raw materials, 8 parts by weight of biological bacteria, 0.2 parts by weight of biological regulator and 6 parts by weight of trace element composition.

[0028] It should be noted that the organic raw materials in this embodiment consist of 15 parts by weight of fermented soybean meal, 8 parts by weight of distiller's grains, and 5 parts by weight of humic acid. The inorganic raw materials consist of 2 parts by weight of ammonium nitrate, 3 parts by weight of superphosphate, and 2 parts by weight of potassium chloride. The microorganisms consist of 4 parts by weight of Bacillus mucilaginosus, 2 parts by weight of Pseudomonas phosphate-solubilizing, and 2 parts by weight of yeast. The biological regulator consists of 0.1 parts by weight of zeatin, 0.05 parts by weight of triacontanol, and 0.05 parts by weight of salicylic acid. The trace element composition consists of 2 parts by weight of borax, 1.5 parts by weight of zinc sulfate, 1 part by weight of ammonium molybdate, 0.5 parts by weight of copper sulfate, 0.5 parts by weight of manganese sulfate, and 0.5 parts by weight of chelated iron.

[0029] Meanwhile, to ensure precise regional loading and avoid interference between components such as cationic trace elements and anionic bacteria, the nanocarrier used in this embodiment consists of 12 parts nano-diatomaceous earth and 3 parts nano-hydroxyapatite. The nano-diatomaceous earth is obtained by sequentially stirring in a 2 mol / L NaOH solution at 60°C for 2 hours, adjusting the pH to 6.0 with a 1 mol / L HCl solution, and then drying at 105°C. The specific surface area of ​​the nano-diatomaceous earth is ≥85 m² / g. 2 / g.

[0030] It should be mentioned that the preparation method of the nanocarrier includes step ① mixing nano-diatomite and nano-hydroxyapatite, adding 0.5% by mass of silane coupling agent KH-550, and obtaining a modified composite carrier by stirring; step ② the modified composite carrier has a particle size of 50-100 nm, and is dispersed in anhydrous ethanol, adding 1% by mass of silane coupling agent KH-792, and refluxed at 70±0.5℃ for 4 h to obtain an aminated composite carrier; step ③ the aminated composite carrier is added to a 2% by mass maleic anhydride ethanol solution, and stirred at 65±0.5℃ for 6 h to obtain an amino-carboxyl bifunctional carrier with a surface amino density ≥2.5 mmol / g and a carboxyl density ≥1.8 mmol / g.

[0031] Furthermore, to further improve the matching effect of flowering period of *Pteris vittata* and avoid the problems of ineffective nutrient release under low temperature and low light and rapid nutrient release under high temperature and high humidity, the amino-carboxyl bifunctional carrier in this application embodiment also includes a core-shell coating treatment. The core-shell coating treatment includes step ① mixing N-isopropylacrylamide and methacrylic acid at a mass ratio of 3:2, adding 0.5% ammonium persulfate as an initiator, and controlling the temperature at 60°C to obtain a shell polymer emulsion; step ② immersing the amino-carboxyl bifunctional carrier in the shell polymer emulsion, and spray drying at an inlet air temperature of 120°C and an outlet air temperature of 50°C to obtain a core-shell coated carrier with a shell membrane thickness of 5-8 μm.

[0032] The application of a compound fertilizer formula for flowering fern includes using the compound fertilizer formula for flowering fern as described above and applying it to the flowering period of fern.

[0033] Example 2

[0034] A compound fertilizer formula for flowering fern root includes 20 parts by weight of nanocarrier, 35 parts of organic raw materials, 11 parts of inorganic raw materials, 10 parts of biological bacteria, 0.25 parts of biological regulator and 8 parts of trace element composition.

[0035] It should be noted that the organic raw materials in this embodiment consist of 17 parts by weight of fermented soybean meal, 10 parts by weight of distiller's grains, and 8 parts by weight of humic acid. The inorganic raw materials consist of 3 parts by weight of ammonium nitrate, 5 parts by weight of superphosphate, and 3 parts by weight of potassium chloride. The microorganisms consist of 5 parts by weight of Bacillus mucilaginosus, 2.5 parts by weight of Pseudomonas phosphate-solubilizing, and 2.5 parts by weight of yeast. The biological regulators consist of 0.1 parts by weight of zeatin, 0.1 parts by weight of triacontanol, and 0.05 parts by weight of salicylic acid. The trace element composition consists of 2.5 parts by weight of borax, 1.6 parts by weight of zinc sulfate, 1.7 parts by weight of ammonium molybdate, 0.8 parts by weight of copper sulfate, 0.6 parts by weight of manganese sulfate, and 1 part by weight of chelated iron.

[0036] Meanwhile, to ensure precise regional loading and avoid interference between components such as cationic trace elements and anionic bacteria, the nanocarrier used in this embodiment consists of 16 parts of nano-diatomite and 4 parts of nano-hydroxyapatite. The nano-diatomite is obtained by sequentially stirring in a 2 mol / L NaOH solution at 60°C for 2 hours, adjusting the pH to 6.0 with a 1 mol / L HCl solution, and then drying at 105°C. The specific surface area of ​​the nano-diatomite is ≥85 m² / g. 2 / g.

[0037] It should be mentioned that the preparation method of the nanocarrier includes step ① mixing nano-diatomite and nano-hydroxyapatite, adding 0.5% by mass of silane coupling agent KH-550, and obtaining a modified composite carrier by stirring; step ② the modified composite carrier has a particle size of 50-100 nm, and is dispersed in anhydrous ethanol, adding 1% by mass of silane coupling agent KH-792, and refluxed at 70±0.5℃ for 4 h to obtain an aminated composite carrier; step ③ the aminated composite carrier is added to a 2% by mass maleic anhydride ethanol solution, and stirred at 65±0.5℃ for 6 h to obtain an amino-carboxyl bifunctional carrier with a surface amino density ≥2.5 mmol / g and a carboxyl density ≥1.8 mmol / g.

[0038] Furthermore, to further improve the matching effect of flowering period of *Pteris vittata* and avoid the problems of ineffective nutrient release under low temperature and low light and rapid nutrient release under high temperature and high humidity, the amino-carboxyl bifunctional carrier in this application embodiment also includes a core-shell coating treatment. The core-shell coating treatment includes step ① mixing N-isopropylacrylamide and methacrylic acid at a mass ratio of 3.1:2, adding 0.5% ammonium persulfate as an initiator, and controlling the temperature at 60°C to obtain a shell polymer emulsion; step ② immersing the amino-carboxyl bifunctional carrier in the shell polymer emulsion, and spray drying at an inlet air temperature of 120°C and an outlet air temperature of 50°C to obtain a core-shell coated carrier with a shell membrane thickness of 5-8 μm.

[0039] The application of a compound fertilizer formula for flowering fern includes using the compound fertilizer formula for flowering fern as described above and applying it to the flowering period of fern.

[0040] Example 3

[0041] A compound fertilizer formula for flowering fern root includes 25 parts by weight of nanocarrier, 44 parts of organic raw materials, 15 parts of inorganic raw materials, 12 parts of biological bacteria, 0.3 parts of biological regulator and 11 parts of trace element composition.

[0042] It should be noted that the organic raw materials in this embodiment consist of 22 parts by weight of fermented soybean meal, 12 parts by weight of distiller's grains, and 10 parts by weight of humic acid. The inorganic raw materials consist of 4 parts by weight of ammonium nitrate, 6 parts by weight of superphosphate, and 5 parts by weight of potassium chloride. The microorganisms consist of 6 parts by weight of Bacillus mucilaginosus, 3 parts by weight of Pseudomonas phosphate-solubilizing, and 3 parts by weight of yeast. The biological regulators consist of 0.15 parts by weight of zeatin, 0.1 parts by weight of triacontanol, and 0.05 parts by weight of salicylic acid. The trace element composition consists of 3 parts by weight of borax, 2 parts by weight of zinc sulfate, 1.5 parts by weight of ammonium molybdate, 1 part by weight of copper sulfate, 1 part by weight of manganese sulfate, and 2 parts by weight of chelated iron.

[0043] Meanwhile, to ensure precise regional loading and avoid interference between components such as cationic trace elements and anionic bacteria, the nanocarrier used in this embodiment consists of 20 parts of nano-diatomite and 5 parts of nano-hydroxyapatite. The nano-diatomite is obtained by sequentially stirring in a 2 mol / L NaOH solution at 60°C for 2 hours, adjusting the pH to 6.0 with a 1 mol / L HCl solution, and then drying at 105°C. The specific surface area of ​​the nano-diatomite is ≥85 m² / g. 2 / g.

[0044] It should be mentioned that the preparation method of the nanocarrier includes step ① mixing nano-diatomite and nano-hydroxyapatite, adding 0.5% by mass of silane coupling agent KH-550, and obtaining a modified composite carrier by stirring; step ② the modified composite carrier has a particle size of 50-100 nm, and is dispersed in anhydrous ethanol, adding 1% by mass of silane coupling agent KH-792, and refluxed at 70±0.5℃ for 4 h to obtain an aminated composite carrier; step ③ the aminated composite carrier is added to a 2% by mass maleic anhydride ethanol solution, and stirred at 65±0.5℃ for 6 h to obtain an amino-carboxyl bifunctional carrier with a surface amino density ≥2.5 mmol / g and a carboxyl density ≥1.8 mmol / g.

[0045] Furthermore, to further improve the matching effect of flowering period of *Pteris vittata* and avoid the problems of ineffective nutrient release under low temperature and low light and rapid nutrient release under high temperature and high humidity, the amino-carboxyl bifunctional carrier in this application embodiment also includes a core-shell coating treatment. The core-shell coating treatment includes step ① mixing N-isopropylacrylamide and methacrylic acid at a mass ratio of 3.2:2, adding 0.5% ammonium persulfate as an initiator, and controlling the temperature at 60°C to obtain a shell polymer emulsion; step ② immersing the amino-carboxyl bifunctional carrier in the shell polymer emulsion, and spray drying at an inlet air temperature of 120°C and an outlet air temperature of 50°C to obtain a core-shell coated carrier with a shell membrane thickness of 5-8 μm.

[0046] The application of a compound fertilizer formula for flowering fern includes using the compound fertilizer formula for flowering fern as described above and applying it to the flowering period of fern.

[0047] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that the preparation method of the nanocarrier in Comparative Example 1 includes mixing nano-diatomite and nano-hydroxyapatite.

[0048] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that the amino-carboxyl bifunctional carrier in Comparative Example 2 was not subjected to shell-core coating treatment.

[0049] Comparative Example 3 The difference between Comparative Example 3 and Example 1 is that ammonium molybdate was not added in Comparative Example 3.

[0050] Performance testing: 1. Experimental Basis: Selected seedlings of *Pteris vittata* with uniform growth, a height of 15-20cm, 6-8 leaves, and free from pests and diseases; a blank control group was set up corresponding to Example 1. The blank control group was not given flowering fertilizer, but only an equal amount of water. Each group was replicated 3 times, with 20 *Pteris vittata* plants per replicate; based on greenhouse or field experiments, the soil type was sandy loam, pH was 6.5-7.0, and soil moisture was 60-70%; fertilizer was applied once in holes at the early budding stage of *Pteris vittata*, with a depth of 5-8cm and an application rate of 15g / plant; 2. Flowering quality: The percentage of flowering plants in each group 20 days after application is taken as the flowering rate; the average number of open flowers per plant in each group of 10 plants is taken as the number of flowers per plant. 3. Nutrient utilization rate: Before application of pesticides and 10 days after flowering, rhizosphere soil samples were taken. Available phosphorus was determined by the molybdenum-antimony colorimetric method and available potassium was determined by the flame photometry method. The nutrient consumption rate was calculated as the available phosphorus / potassium content of the soil. After flowering, the plants were harvested, and the stems, leaves and flower buds were dried, weighed, digested, and nitrogen was determined by the Kjeldahl method, phosphorus by the molybdenum-antimony colorimetric method, and potassium by the flame photometry method. The total accumulation per plant was calculated as the nitrogen / phosphorus / potassium accumulation of the plant. 4. Stress resistance matching: The flower drop rate and recovery flowering rate were counted as the low temperature and low light stress response under artificially simulated low temperature of 12℃ and low light of 4h / day for 3 days; the flower deformity rate and nutrient leaching amount were counted as the high temperature and high humidity stress response under artificially simulated high temperature of 30℃ and high humidity of 90% for 3 days. 5. Bioactivity: Rhizosphere soil was collected after flowering, and the number of Bacillus spp. and Pseudomonas phosphate-solubilizing bacteria was counted using the dilution plate counting method to determine the number of effective bacteria in the rhizosphere.

[0051] The performance test results are shown in Table 1 below.

[0052] Table 1 Performance Test Results

[0053] As shown in Table 1 above, in Examples 1-3 of this application, fermented soybean meal, distiller's grains, and humic acid from the organic raw materials provide slow-release carbon sources and amino acids to *Strombax ceiba pentans*, promoting the reproduction of beneficial microorganisms and improving soil aggregate structure and root absorption capacity. Ammonium nitrate, superphosphate, and potassium chloride from the inorganic raw materials promote flower organ development by providing readily available nitrogen necessary for flowering, promote flower bud differentiation by providing phosphorus, and enhance stress resistance by providing potassium. *Bacillus mucilaginosus* from the beneficial microorganisms fixes nitrogen, while *Pseudomonas phosphate-solubilizing* is used for phosphorus solubilization, converting unavailable phosphorus in the soil into available phosphorus.

[0054] In Comparative Example 1, the carrier lacked sufficient loading capacity and was not modified or treated with maleic anhydride, thus lacking amino-carboxyl bigroups and charge sites. This resulted in direct contact between the bacteria and trace elements, and the toxicity of trace elements to bacteria caused a sharp drop in bacterial activity. Simultaneously, the unmodified carrier had low surface area utilization, failing to effectively adsorb inorganic nutrients, leading to easy nutrient leaching. Furthermore, the bacteria, lacking carrier protection, were susceptible to inactivation under environmental stress.

[0055] Comparative Example 2, due to its lack of environmental responsiveness, resulted in continuous nutrient release under low temperature and low light conditions, but the plants were unable to absorb it, leading to waste and making the roots susceptible to high-concentration nutrient stress. Furthermore, under high temperature and high humidity, the high temperature accelerated nutrient dissolution, resulting in excessively high concentrations in a short period, causing deformed flower organs and increased nutrient leaching. In contrast, Examples 1 to 3 showed that under low temperature and low light conditions, the polymer shell contracted, reducing the pore size and allowing for slow nutrient release, avoiding nutrient retention and ineffectiveness due to weak plant absorption; and under high temperature and high humidity conditions, the polymer shell swelled, allowing for controllable expansion of the pore size, promoting a stable nutrient release and avoiding problems such as flower burn or leaching loss caused by sudden release.

[0056] In Comparative Example 3, molybdenum, as a component of nitrogenase, promotes nitrogen fixation efficiency in rhizosphere bacteria, providing nitrogen reserves for fruit set after flowering. Therefore, without its addition, molybdenum leads to pollen deformities and a decreased fertilization rate, directly reducing fruit set. However, since molybdenum only affects the fertilization stage of reproductive growth and does not directly participate in nutrient adsorption or stress resistance structure construction, the stress resistance and number of bacteria in Comparative Example 3 are similar to those in Example 1, but the fruit set rate is significantly lower.

[0057] In summary, this application provides a compound fertilizer formula for *Pteris vittata* flowering and its application. When applied to *Pteris vittata* during its flowering period, this compound fertilizer formula directly promotes flower bud differentiation and floral organ development through bio-regulators. Combined with the continuous nutrients provided by organic raw materials and the efficient adsorption and slow-release effect of nano-carriers, it provides sufficient and stable nutrition for flower bud formation, significantly increasing the number and uniformity of flowers. Simultaneously, trace elements promote pollen germination and pollen tube elongation, solving the problem of low fruit set due to poor pollination. Biological bacteria activate soil nutrients and improve root absorption capacity. Combined with the precise nutrient release of the shell-core coated carrier, it provides essential nutrients for ovary development after pollination during the critical flowering stage, reducing flower and fruit drop. Furthermore, the dual slow-release system formed by the amino-carboxyl dual-group carrier and the shell-core coated structure effectively avoids nutrient imbalance in the plant caused by the sudden release of inorganic nutrients. This synergistic effect of biological bacteria improves the soil microenvironment, enhances the stress resistance of *Pteris vittata*, and reduces the impact of adverse environmental conditions during flowering on fruit set, thereby effectively improving the flowering and fruit set rates of *Pteris vittata*.

[0058] The terms “first,” “second,” “third,” “fourth,” etc., used in this application (if applicable) are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, or apparatus that includes a series of steps or units is not necessarily limited to those explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, or apparatus.

[0059] It should be noted that the use of terms such as "first" and "second" in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of those features. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed in this application.

[0060] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A compound fertilizer formula for flowering fern shoots, characterized in that: It includes 15-25 parts by weight of nanocarrier, 28-44 parts of organic raw materials, 7-15 parts of inorganic raw materials, 8-12 parts of biological bacteria, 0.2-0.3 parts of bioregulators, and 6-11 parts of trace element composition; wherein: The nanocarrier is composed of 12-20 parts of nano-diatomite and 3-5 parts of nano-hydroxyapatite; the nano-diatomite is obtained by sequentially stirring with 2 mol / L NaOH solution at 60℃ for 2 h and adjusting the pH to 6.0 with 1 mol / L HCl solution, and then drying at 105℃; the specific surface area of ​​the nano-diatomite is ≥85 m² / g. 2 / g.

2. The compound fertilizer formula for flowering fern root according to claim 1, characterized in that: The preparation method of the nanocarrier includes step ① mixing nano-diatomite and nano-hydroxyapatite, adding 0.5% by mass of silane coupling agent KH-550, and obtaining a modified composite carrier by stirring; step ② the modified composite carrier has a particle size of 50-100 nm, and is dispersed in anhydrous ethanol, adding 1% by mass of silane coupling agent KH-792, and refluxed at 70±0.5℃ for 4 h to obtain an aminated composite carrier; step ③ the aminated composite carrier is added to a 2% by mass maleic anhydride ethanol solution, and stirred at 65±0.5℃ for 6 h to obtain an amino-carboxyl bifunctional carrier with a surface amino density ≥2.5 mmol / g and a carboxyl density ≥1.8 mmol / g.

3. The compound fertilizer formula for flowering fern root according to claim 2, characterized in that: The amino-carboxyl bifunctional carrier further includes a core-shell coating treatment; the core-shell coating treatment includes step ① mixing N-isopropylacrylamide and methacrylic acid at a mass ratio of 3-3.2:2, adding 0.5% ammonium persulfate as an initiator, and controlling the temperature at 60°C to obtain a shell polymer emulsion; step ② immersing the amino-carboxyl bifunctional carrier in the shell polymer emulsion, and spray drying the mixture to obtain a core-shell coated carrier.

4. The compound fertilizer formula for flowering fern root according to claim 2, characterized in that: The inlet air temperature of the spray drying process is 120℃, and the outlet air temperature is 50℃; the shell membrane thickness of the core-shell coated carrier is 5-8μm.

5. The compound fertilizer formula for fern root flowering as described in claim 1, characterized in that: The organic raw material consists of 15-22 parts by weight of fermented soybean meal, 8-12 parts by weight of distiller's grains, and 5-10 parts by weight of humic acid.

6. The compound fertilizer formula for flowering fern root according to claim 1, characterized in that: The inorganic raw material consists of 2-4 parts by weight of ammonium nitrate, 3-6 parts by weight of superphosphate, and 2-5 parts by weight of potassium chloride.

7. The compound fertilizer formula for flowering fern root according to claim 1, characterized in that: The microorganisms consist of 4-6 parts by weight of Bacillus spp. gelatinosa, 2-3 parts by weight of Pseudomonas phosphate-solubilizingis, and 2-3 parts by weight of yeast, with a viable count ≥ 2 × 10⁻⁶. 9 CFU / g.

8. The compound fertilizer formula for flowering fern root according to claim 1, characterized in that: The bioregulator is composed of 0.1-0.15 parts by weight of zeatin, 0.05-0.1 parts by weight of triacontanol and 0.05 parts by weight of salicylic acid.

9. The compound fertilizer formula for flowering fern root according to claim 1, characterized in that: The trace element composition consists of 2-3 parts by weight of borax, 1.5-2 parts by weight of zinc sulfate, 1-1.5 parts by weight of ammonium molybdate, 0.5-1 parts by weight of copper sulfate, 0.5-1 parts by weight of manganese sulfate, and 0.5-2 parts by weight of chelated iron.

10. The application of a compound fertilizer formula for flowering fern root, characterized in that: This includes using a compound fertilizer formula for flowering fern as described in any one of claims 1-9, and applying it to the flowering period of fern.

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