A pyraclostrobin-kresoxim-methyl aqueous emulsion and a preparation method thereof

Abstract

The present application relates to a kind of pyraclostrobin chlorothalonil water emulsion and its preparation method, it relates to the technical field of pesticide preparation, wherein, by mass percentage, the water emulsion includes pyraclostrobin 8-12%, chlorothalonil 16-24%, solvent 10-18%, composite surfactant 8-15%, photosynthesis promoter 2-6%, penetration spreader 3-8%, epichlorohydrin 1-3%, glycerol 3-6%, organic silicon defoaming agent 0.1-0.5%, the rest is water;The mass ratio of pyraclostrobin and chlorothalonil is 1:2.The present application realizes the rapid penetration of liquid medicine and the rapid dry of disease spot by accurate particle size control and formula system, simultaneously significantly enhances the photosynthesis of crops using photosynthesis promoter, realizes the dual effect of spot control and leaf, quality increase and yield increase while high-efficiency sterilization.

Description

Technical Field

[0001] This invention relates to the field of pesticide formulation technology, and in particular to a pyraclostrobin·bromodiphenyl ether emulsion and its preparation method. Background Technology

[0002] Pyraclostrobin, a methoxyacrylate fungicide, exerts its bactericidal effect by inhibiting mitochondrial respiration. It also possesses plant health regulating functions, increasing chlorophyll content, delaying senescence, and improving crop yield. Bromhexanil is a broad-spectrum, low-toxicity fungicide, highly effective against anthracnose. The combination of these two fungicides exhibits a significant synergistic effect, providing broad-spectrum control and effectively preventing anthracnose, black spot, gray mold, scab, and other diseases.

[0003] In the prior art, Chinese invention patent CN103004823A discloses a compound fungicide composition containing pyraclostrobin and bromuconazole. Chinese invention patent CN104970032A discloses a pesticide microemulsion containing bromuconazole and pyraclostrobin.

[0004] However, existing formulations mainly address the issues of broadening the fungicidal spectrum and extending the duration of action. They lack targeted formulation designs for maximizing the plant health regulation function of pyraclostrobin while rapidly controlling lesions, thus achieving a synergistic effect of lesion control and leaf enhancement. Existing water-in-oil emulsions have the following technical defects: (1) Ordinary water-in-oil emulsions have a wide particle size distribution in the dispersed phase, with a high proportion of large-diameter droplets, resulting in low adhesion and penetration efficiency of the active ingredients on crop leaves, affecting the speed of action; (2) They fail to design synergistic effects on the plant health regulation function of pyraclostrobin, resulting in limited activation efficiency of crop photosynthesis; (3) They have poor spreadability on highly hydrophobic fruit tree leaves (such as mango and citrus) and fruit surfaces (such as apple russeting areas), making the solution easy to roll off and affecting the control effect; (4) For lesions that have already formed, ordinary formulations require a long time to control the spread of lesions, which cannot meet growers' expectations for rapid lesion control.

[0005] Therefore, developing a synergistic pyraclostrobin·bromodiphenyl ether emulsion that can quickly eliminate spots and significantly enhance crop photosynthesis is of great practical significance. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a pyraclostrobin·bromodiphenyl ether emulsion and its preparation method. Through precise particle size control and a well-designed formulation, this invention achieves rapid penetration of the solution and quick drying of lesions. Simultaneously, it utilizes a photosynthesis promoter to significantly enhance crop photosynthesis, achieving the dual effects of highly effective fungicide control, improved leaf appearance, and increased yield.

[0007] In a first aspect, the present invention provides a pyraclostrobin·bromodiflubenzuron water-in-oil emulsion, wherein, by mass percentage, the water-in-oil emulsion comprises 8-12% pyraclostrobin, 16-24% bromodiflubenzuron, 10-18% solvent, 8-15% composite surfactant, 2-6% photosynthesis promoter, 3-8% penetrating and spreading agent, 1-3% epichlorohydrin, 3-6% glycerol, 0.1-0.5% organosilicon defoamer, and the balance being water; the mass ratio of pyraclostrobin to bromodiflubenzuron is 1:2.

[0008] In the above technical solutions, pyraclostrobin, as a mitochondrial respiration inhibitor, causes pathogens to die due to disrupted energy metabolism by blocking electron transport. It can also induce a defensive response in crops, activating multiple defense enzyme systems; increase chlorophyll content in leaves, delay leaf senescence, and improve photosynthetic efficiency. Furthermore, it regulates the balance of hormones within plants, enhancing their resistance to adverse conditions.

[0009] Bromoxyfenozide is a broad-spectrum fungicide that effectively kills Deuteromycetes fungi (especially anthracnose fungi) by interfering with the cell membrane function of pathogens. It can also compensate for the insufficient efficacy of pyraclostrobin alone against certain diseases.

[0010] Epichlorohydrin acts as a stabilizer to prevent the hydrolysis and oxidative decomposition of active ingredients, and synergistically enhances the strength of the interfacial film with surfactants, thereby improving emulsion stability.

[0011] Glycerol, as an antifreeze agent, can lower the freezing point of formulations and ensure stability during low-temperature storage. It also has a moisturizing effect, delaying the drying time of drug drops and promoting absorption.

[0012] Organosilicon defoamers can prevent excessive foaming during production and use, ensuring accurate measurement and ease of use.

[0013] Optionally, the photosynthesis promoter is a complex of chlorogenic acid and zinc ions in a molar ratio of 1:1. The preparation steps of the complex are as follows: Chlorogenic acid is added to water, heated to 50-60℃, and stirred until completely dissolved to prepare a 0.05-0.1 mol / L chlorogenic acid solution. Zinc sulfate is dissolved in water to prepare a 0.025-0.05 mol / L zinc salt solution. Under stirring at 300-400 rpm, the zinc salt solution is slowly added dropwise to the chlorogenic acid solution at a dropping rate of 2-3 mL / min. The reaction temperature is maintained at 50-60℃, and the reaction is continuously stirred for 2-3 hours. Finally, the pH of the reaction solution is slowly adjusted to 5.5-6.5 with 0.1 mol / L dilute NaOH solution to obtain the complex.

[0014] In the above technical solution, chlorogenic acid, as a natural phenolic acid compound, has antioxidant properties and can scavenge reactive oxygen species. It can induce disease resistance in plants, activate defense enzyme systems, and protect chloroplast membrane structures. Zinc ions, as an essential element for chlorophyll synthesis and a cofactor for many photosynthetic enzymes, can promote auxin synthesis.

[0015] Pyraclostrobin itself can increase chlorophyll content and delay senescence. The chlorogenic acid-zinc complex directly provides zinc, a raw material for chlorophyll synthesis, and chlorogenic acid, which protects chloroplasts. The synergistic effect of both increases chlorophyll content far beyond the effect of using either alone. Pyraclostrobin induces a defense response in plants, activating some defense enzymes. Chlorogenic acid directly activates these enzymes, and the synergistic effect enhances their activity, leading to stronger systemic resistance in crops. Disease infection causes oxidative stress in plants. Pyraclostrobin reduces oxidative damage by regulating plant metabolism, while chlorogenic acid directly scavenge reactive oxygen species. Together, they protect cell membranes and chloroplast structure.

[0016] Optionally, the penetrating spreader is a composition of organosilicon-modified polyether and vegetable oleic acid in a mass ratio of 1.5-2.5:1.

[0017] In the above technical solution, organosilicon allows the pesticide solution to spread instantly on the leaf surface and enter the leaf interior through stomata. Plant oleic acid softens the cuticle and promotes transmembrane transport. The synergistic effect of these two substances further enhances the penetration of the active ingredient in a short time, achieving rapid sterilization. The active ingredient quickly reaches the site of pathogen infection, reaching a lethal concentration before the pathogen develops resistance. The penetrating spreader helps the active ingredient penetrate the cell walls of pathogen hyphae; the synergistic effect of these two substances causes rapid shrinkage of lesions after application. Organosilicon forms a uniform film on the leaf surface with good adhesion after drying, while plant oleic acid increases the adhesiveness of the pesticide solution; the synergistic effect of these two substances reduces rainwater runoff loss.

[0018] Meanwhile, organosilicon helps the pesticide spread to all parts of the leaves, while plant oleic acid softens the cuticle and promotes the transmembrane transport of zinc ions. Together, they can improve the absorption rate of zinc on the leaf surface. Plant oleic acid forms a protective film on the leaf surface, reducing the photolysis and oxidation of chlorogenic acid, while organosilicon helps chlorogenic acid to be evenly distributed on the leaf surface. Together, they prolong the duration of chlorogenic acid's effectiveness on the leaf surface.

[0019] Optionally, the organosilicon-modified polyether is polyether-modified heptamethyltrisiloxane, and the vegetable oleic acid is plant-derived oleic acid with an oleic acid content ≥75%. The preparation steps of the polyether-modified heptamethyltrisiloxane are as follows: heptamethyltrisiloxane and allyl polyether in a molar ratio of 1:1.05-1.1 are dissolved in toluene, added to a four-necked flask, protected by nitrogen, heated to 75-85℃, chloroplatinic acid catalyst is added, the temperature is raised to 110-115℃, and the reaction is carried out for 4-6 hours. After the reaction is completed, the solvent is removed by vacuum distillation, activated carbon is added for decolorization, the mixture is stirred at 55-65℃ for 25-35 minutes, and filtered to obtain the polyether-modified heptamethyltrisiloxane.

[0020] Optionally, the solvent is a mixture of cyclohexanone and Solvesso 200 in a volume ratio of 2-4:1.

[0021] In the above technical solution, cyclohexanone is used to dissolve the active ingredient, forming a stable oil phase with a moderate boiling point, which contributes to the stability of the formulation. Solvesso 200, as an aromatic solvent, has good solubility for bromodiphenyl ether and low volatility, which can reduce the problem of poor absorption caused by excessively rapid drying of the drug solution.

[0022] Optionally, the composite surfactant is a compound of phenylethylphenol polyoxyethylene ether and calcium dodecylbenzenesulfonate in a mass ratio of 2.5-3.5:1.

[0023] In the above technical solution, phenethylphenol polyoxyethylene ether, as a nonionic emulsifier, provides steric stabilization, reduces oil-water interfacial tension, promotes emulsification, and enhances the wettability of the pesticide solution on the leaf surface. Calcium dodecylbenzenesulfonate, as an anionic emulsifier, provides charge repulsion stabilization and, when combined with nonionic surfactants, produces a synergistic emulsifying effect.

[0024] Secondly, the present invention provides a method for preparing a pyraclostrobin·bromodiphenyl ether emulsion, the preparation method comprising the following steps: (1) Preparation of oil phase: Weigh pyraclostrobin and bromodiphenyl ether according to the ratio, add them to the solvent, heat to 40-50℃ and stir to dissolve, then add the composite surfactant and stir evenly to obtain the oil phase; (2) Preparation of aqueous phase: Weigh the photosynthesis promoter, glycerol and some water according to the ratio, mix and stir until completely dissolved to obtain the aqueous phase; (3) Primary emulsification: Under high-speed shearing conditions, the aqueous phase is slowly added to the oil phase at a shearing speed of 2000-3000 rpm and a shearing time of 15-30 min to obtain a primary emulsion; (4) Homogenization and refinement: The primary emulsion is homogenized 1-3 times under a pressure of 30-50MPa using a high-pressure homogenizer; (5) Post-mixing: Add penetrating spreading agent, epichlorohydrin and organosilicon defoamer, stir and mix evenly, add the remaining water, continue stirring for 10-15 minutes, take a sample for testing and filter after passing the test, and you will get pyraclostrobin·bromodimethalin emulsion.

[0025] In the above technical solution, during the aqueous phase preparation step, water is added first, followed by the dissolution of the chlorogenic acid-zinc complex, and finally glycerol. This is because the solubility of the chlorogenic acid-zinc complex in water is limited, and adding pure water first provides the maximum driving force for dissolution. If glycerol is added first, the activity of water decreases, and the solubility declines. If the order is reversed, the chlorogenic acid-zinc complex will not dissolve completely, the aqueous phase will be turbid, and the functional components in the final product will be unevenly distributed.

[0026] The reason for adding a penetrating spreader after homogenization is that the polyether segments of organosilicon-modified polyether are sensitive to high shear. The mechanical force of high-pressure homogenization may break the polyether chains, destroy their surface activity, and reduce their spreadability.

[0027] Thirdly, the present invention provides the application of the above-mentioned pyraclostrobin·bromodiflubenzuron water-in-oil emulsion in the prevention and control of anthracnose in fruit trees, melons and vegetables, wherein the fruit trees include apples, pears, citrus and mangoes, the melons include watermelons and cantaloupes, and the vegetables include eggplants, peppers and strawberries.

[0028] In summary, the present invention has at least one of the following beneficial technical effects: 1. This invention combines pyraclostrobin and bromuconazole in a 1:2 ratio, with complementary mechanisms of action and a broadened fungicidal spectrum. The product of this invention is highly effective against anthracnose and also has excellent control effects on a variety of diseases such as black spot, gray mold, scab, vine blight, leaf spot, grease spot, and black and red spot.

[0029] 2. This invention adds chlorogenic acid-zinc complex as a photosynthesis promoter, which synergistically enhances the plant health regulation function of pyraclostrobin. Chlorogenic acid provides antioxidant protection, and zinc ions are an essential element for chlorophyll synthesis and a cofactor for photosynthetic enzymes. The bioavailability is improved after the two are complexed.

[0030] 3. This invention forms a dense oil-water interface film by combining the synergistic emulsification effect of composite surfactants with high-pressure homogenization process to control particle size. At the same time, epichlorohydrin acts as a stabilizer to further enhance the strength of the interface film and inhibit the hydrolysis of active ingredients.

[0031] 4. This invention utilizes the synergistic effect of penetrating spreaders and organosilicon to allow the liquid to spread instantly on the leaf surface and enter the leaf interior through stomata. Plant oil acids soften the cuticle and promote transmembrane transport. The synergistic effect of both increases the penetration of active ingredients in a short time, achieving rapid sterilization.

[0032] 5. This invention uses organosilicon-modified polyether in the penetrating spreader to form a uniform film on the leaf surface, which has good adhesion after drying; plant oleic acid increases the adhesion of the liquid, and the synergistic effect of the two significantly improves the liquid's resistance to rain washout, making it suitable for use in rainy areas and rainy seasons.

[0033] 6. The preparation method of the present invention is simple to operate, has low energy consumption, good reproducibility, and is suitable for large-scale industrial production. The order of addition of each component has been optimized, which not only protects the activity of sensitive functional components, but also ensures the stability of the product. Detailed Implementation

[0034] The present invention will be further described in detail below with reference to the embodiments.

[0035] All materials used in the following examples are available for purchase on the market.

[0036] Example 1: This example provides a pyraclostrobin·bromodiphenyl ether emulsion and its preparation method.

[0037] The water-in-oil emulsion comprises, by mass percentage: 8% pyraclostrobin, 16% bromodiphenyl ether, 10% a mixed solvent of cyclohexanone and Solvesso 200 (volume ratio 3:1), 8% composite surfactant, 2% photosynthesis promoter, 3% penetrating spreader, 1% epichlorohydrin, 3% glycerol, 0.1% silicone defoamer, with the balance being water; the mass ratio of pyraclostrobin to bromodiphenyl ether is 1:2. The photosynthesis promoter is a complex of chlorogenic acid and zinc ions in a molar ratio of 1:1. The penetrating spreader is a composition of polyether-modified heptamethyltrisiloxane and plant-derived oleic acid with an oleic acid content ≥75% in a mass ratio of 2:1. The composite surfactant is a compound of phenethylphenol polyoxyethylene ether and calcium dodecylbenzenesulfonate in a mass ratio of 3:1.

[0038] The preparation method includes the following steps: S1. Preparation of chlorogenic acid-zinc complex: Chlorogenic acid was added to deionized water, heated to 55℃, and stirred until completely dissolved to prepare a 0.08 mol / L chlorogenic acid solution. Zinc sulfate was dissolved in water to prepare a 0.04 mol / L zinc salt solution. Under stirring at 350 rpm, the zinc salt solution was slowly added dropwise to the chlorogenic acid solution at a rate of 2.5 mL / min. The reaction temperature was maintained at 55℃, and the reaction was stirred continuously for 2.5 h. Then, the pH of the reaction solution was slowly adjusted to 6.0 with 0.1 mol / L dilute NaOH solution, and stirring was continued for 30 min to obtain an aqueous solution of chlorogenic acid-zinc complex.

[0039] S2. Preparation of polyether-modified heptamethyltrisiloxane: In a dry four-necked flask, heptamethyltrisiloxane and allyl polyether (molecular weight 600) were added in a molar ratio of 1:1.08. An appropriate amount of toluene was added to make the solid content about 60%. Under nitrogen protection, the mixture was heated to 80°C, and chloroplatinic acid catalyst (platinum dosage 15 ppm) was added. The temperature was raised to 112°C and refluxed for 5 h. After the reaction was completed, the solvent was removed by vacuum distillation, activated carbon was added for decolorization, and the mixture was stirred at 60°C for 30 min. After filtration, the polyether-modified heptamethyltrisiloxane was obtained.

[0040] S3. Preparation of oil phase: Weigh out pyraclostrobin and bromodiphenyl ether according to the formula, add them to a mixed solvent of cyclohexanone and Solvesso 200, heat to 45°C, stir at 350 rpm for 25 min until completely dissolved, then add the composite surfactant and continue stirring for 15 min to obtain a homogeneous oil phase.

[0041] S4. Preparation of aqueous phase: Weigh out chlorogenic acid-zinc complex, glycerol and 60% water according to the formula, and stir at 250 rpm for 15 min at room temperature until completely dissolved to obtain the aqueous phase.

[0042] S5. Primary Emulsification: The oil phase is transferred to a high-speed shear emulsification vessel. Under shear conditions of 2800 rpm, the aqueous phase is slowly added to the oil phase at a rate of 2.5 L / min. After the addition is complete, shearing continues for 20 min to obtain the primary emulsion.

[0043] S6. Homogenization and Refinement: The primary emulsion is homogenized twice under a high-pressure homogenizer at a pressure of 45 MPa.

[0044] S7. Post-mixing: Transfer the homogenized emulsion to a mixing tank, add the penetrating spreader, epichlorohydrin and organosilicon defoamer, stir at 120 rpm for 15 min to mix evenly, then add the remaining deionized water, continue stirring for 10 min, take a sample for testing and filter after passing the test, and you will get pyraclostrobin·bromodimethalin emulsion.

[0045] Example 2: This example provides a pyraclostrobin·bromodiphenyl ether emulsion and its preparation method.

[0046] The water-in-oil emulsion comprises, by mass percentage: 12% pyraclostrobin, 24% bromodiphenyl ether, 18% a mixed solvent of cyclohexanone and Solvesso 200 (volume ratio 3:1), 15% a composite surfactant, 6% a photosynthesis promoter, 8% a penetrating and spreading agent, 3% epichlorohydrin, 6% glycerol, 0.5% a silicone defoamer, and the balance being water; the mass ratio of pyraclostrobin to bromodiphenyl ether is 1:2. The photosynthesis promoter is a complex of chlorogenic acid and zinc ions in a molar ratio of 1:1. The penetrating and spreading agent is a composition of polyether-modified heptamethyltrisiloxane and plant-derived oleic acid with an oleic acid content ≥75% in a mass ratio of 1.5:1. The composite surfactant is a compound of phenethylphenol polyoxyethylene ether and calcium dodecylbenzenesulfonate in a mass ratio of 3:1.

[0047] The preparation method is the same as in Example 1.

[0048] Example 3: This example provides a pyraclostrobin·bromodiphenyl ether emulsion and its preparation method.

[0049] The water-in-oil emulsion comprises, by mass percentage: 10% pyraclostrobin, 20% bromodiphenyl ether, 14% a mixed solvent of cyclohexanone and Solvesso 200 (volume ratio 3:1), 12% a composite surfactant, 4% a photosynthesis promoter, 5% a penetrating and spreading agent, 2% epichlorohydrin, 4% glycerol, 0.3% a silicone defoamer, and the balance being water; the mass ratio of pyraclostrobin to bromodiphenyl ether is 1:2. The photosynthesis promoter is a complex of chlorogenic acid and zinc ions in a molar ratio of 1:1. The penetrating and spreading agent is a composition of polyether-modified heptamethyltrisiloxane and plant-derived oleic acid with an oleic acid content ≥75% in a mass ratio of 1.5:1. The composite surfactant is a compound of phenethylphenol polyoxyethylene ether and calcium dodecylbenzenesulfonate in a mass ratio of 3:1.

[0050] The preparation method is the same as in Example 1.

[0051] Example 4: This example provides a pyraclostrobin·bromodiphenyl ether emulsion and its preparation method.

[0052] The pyraclostrobin·bromodiphenyl ether emulsion and its preparation method in this embodiment are the same as those in Example 3, except that the homogenization pressure is 35 MPa and the homogenization is performed twice.

[0053] Example 5: This example provides a pyraclostrobin·bromodiphenyl ether emulsion and its preparation method.

[0054] The pyraclostrobin·bromodiphenyl ether emulsion and its preparation method in this embodiment are the same as those in Example 3, except that the penetrating spreader is a combination of organosilicon-modified polyether and vegetable oleic acid with a mass ratio of 1.5:1.

[0055] Example 6: This example provides a pyraclostrobin·bromodiphenyl ether emulsion and its preparation method.

[0056] The pyraclostrobin·bromodiphenyl ether emulsion and its preparation method in this embodiment are the same as those in Example 5, except that the composite surfactant is a compound of phenylethylphenol polyoxyethylene ether and calcium dodecylbenzenesulfonate in a mass ratio of 3.5:1.

[0057] Example 7: This example provides a pyraclostrobin·bromodiphenyl ether emulsion and its preparation method.

[0058] The pyraclostrobin·bromodiphenyl ether emulsion and its preparation method in this embodiment are the same as those in Example 5, except that the solvent is a mixture of cyclohexanone and Solvesso 200 in a volume ratio of 4:1.

[0059] Comparative Example 1: This comparative example provides a comparative water-in-oil emulsion that is the same as that in Example 5, except that no photosynthesis promoter is added.

[0060] Comparative Example 2: This comparative example provides a comparative water-based emulsion that is the same as that in Example 5, except that no penetrating and spreading agent is added.

[0061] Comparative Example 3: This comparative example provides a comparative water-in-oil emulsion that is the same as that in Example 5, except that the photosynthesis promoter is a mixture of chlorogenic acid and zinc sulfate in a molar ratio of 1:1.

[0062] Comparative Example 4: This comparative example provides a comparative water-in-oil emulsion that is the same as that in Example 5, except that the preparation method does not include the S6 homogenization and refining step.

[0063] Comparative Example 5: This comparative example provides a comparative water-in-oil emulsion that is the same as that in Example 5, except that the penetrating spreading agent is added during the preparation of the S3 oil phase.

[0064] I. Particle size and physical stability test Particle size and distribution were tested on the pyraclostrobin·bromodiphenyl ether emulsions obtained in Examples 1-7 and the control emulsions obtained in Comparative Examples 1-5.

[0065] 1. Particle size and distribution determination: Malvern 2000 laser particle size analyzer was used. Deionized water was used as the dispersion medium. After ultrasonic dispersion for 1 min, the volume average particle size Dv50 and particle size distribution (<1.0 μm percentage, >3.0 μm percentage) were determined.

[0066] 2. Physical stability determination: Thermal storage stability: Take 100 mL of sample and seal it in a glass bottle. Store it in a constant temperature chamber at (54±2)℃ for 14 days. After taking it out and restoring it to room temperature, observe its appearance and measure the change in particle size. Calculate the particle size growth rate = (Dv50 after thermal storage - initial Dv50) / initial Dv50 × 100%.

[0067] Cold storage stability: Take 100 mL of sample, seal it in a glass bottle, and store it in a refrigerator at (0±2)℃ for 7 days. After taking it out and restoring it to room temperature, observe whether there is any crystal precipitation or layering.

[0068] The test results are shown in Table 1.

[0069] Table 1

[0070] As can be seen from the data in Table 1, Examples 1-7 all achieved Dv50 within the range of 0.9-1.25 μm, with the proportion of particles <1.0 μm exceeding 72% and the proportion of large particles >3.0 μm ≤1.5%, indicating that the formulation and process of this invention have good particle size control capabilities. Example 4 (homogenization pressure 35 MPa) had a slightly larger particle size (1.25 μm), but still met the requirements. Comparative Example 4 (no homogenization) had the largest particle size (2.80 μm), and the particle size increased significantly after heat storage (23.2%), indicating that high-pressure homogenization is crucial for achieving the core particle size characteristics of this invention.

[0071] The particle size growth rate after thermal storage in Examples 1-7 was all <20%, which was much lower than 23.2% in Comparative Example 4 and 20.0% in Comparative Example 5. The particles were stable after cold storage, indicating that the synergistic effect of the composite surfactant and epichlorohydrin formed a dense interfacial film, ensuring excellent physical stability.

[0072] II. Testing of Surface Tension, Contact Angle, and Penetration The surface tension, contact angle and spreadability tests, and leaf penetration were performed on the pyraclostrobin·bromodiphenyl ether emulsions obtained in Examples 1-7 and the comparative emulsions obtained in Comparative Examples 1-5.

[0073] 1. Surface tension measurement: The surface tension of each sample in 0.1% aqueous solution (based on effective ingredient) at 25℃ was measured using a QBZY series fully automatic surface tension meter (platinum plate method).

[0074] 2. Contact angle and spreadability: Using a JC2000D contact angle meter, fresh mango leaves (with thick wax layer) were laid flat on the stage, and 2 μL of sample dilution solution (diluted 1500 times) was added. The stable contact angle was measured (10 replicates were taken and the average was taken).

[0075] 3. Determination of leaf permeability: Take fresh mango leaves, cut leaf discs with a diameter of 2 cm, float them in the sample dilution solution (diluted 1500 times), take them out after 24 h, rinse the surface with deionized water, dry them, extract the active ingredients, determine the pyraclostrobin content by HPLC, and calculate the permeability per unit leaf area.

[0076] The test results are shown in Table 2.

[0077] Table 2

[0078] As shown in Table 2, the examples and Comparative Examples 1 and 3 containing the penetrating spreader of this invention (organosilicon-modified polyether + vegetable oleic acid) all exhibited surface tension ≤24.2 mN / m and contact angle ≤26.8°, demonstrating excellent spreading performance. Comparative Example 2, without the added penetrating spreader, showed a surface tension as high as 42.1 mN / m and a contact angle of 56.3°, indicating that the penetrating spreader is crucial for achieving rapid penetration. In Comparative Example 5, the penetrating spreader was added before homogenization, resulting in a surface tension of 34.0 mN / m, higher than the 23.5 mN / m of Example 5. This demonstrates that the organosilicon-modified polyether is highly shear-sensitive, and high-pressure homogenization would damage its molecular structure; the subsequent addition protected the activity of the organosilicon structure.

[0079] III. Field efficacy trials 1. Control efficacy against mango anthracnose: The experiment was conducted in Sanya City, Hainan Province, using the Tainong No. 1 variety. The drug was applied at the early stage of disease, with four replicates per treatment, arranged in a randomized block design. Disease index was assessed at 3, 7, and 14 days after application, and control efficacy was calculated. Three days after application, 30 new lesions (5-8 mm in diameter) were marked for each treatment, and the lesion diameter was measured. The lesion shrinkage rate was calculated as: (Pre-treatment diameter - Post-treatment diameter) / Pre-treatment diameter × 100%.

[0080] The test results are shown in Table 3.

[0081] Table 3

[0082] As shown in Table 3, the anthracnose control data for mangoes in Example 5 indicates that the lesion shrinkage rate reached 53.1% three days after application, meaning that more than half of the lesion area had dried and shrunk, achieving the expected goal of rapid lesion shrinkage. The control efficacy was 87.0% seven days after application and remained at 84.2% fourteen days after application, demonstrating excellent rapid and sustained efficacy.

[0083] Example 4 (particle size 1.25 μm) showed a lesion shrinkage rate of 45.3%, lower than the 53.1% of Example 5, indicating that smaller particle size leads to better rapid efficacy. Comparative Example 2, without the addition of a penetrating spreader, showed a lesion shrinkage rate of only 28.4%, a significant decrease in efficacy, indicating that the penetrating spreader promotes rapid penetration, allowing the active ingredients to quickly reach the pathogen target, which is the core factor in achieving rapid lesion shrinkage. Comparative Example 4, without homogenization, showed a lesion shrinkage rate of 30.2%, demonstrating the important influence of particle size control on rapid efficacy. Comparative Example 5, with the penetrating spreader added during the S3 oil phase preparation process, showed a lesion shrinkage rate of 36.5%, a decrease of 31%, indicating that subsequent addition protects the activity of the spreader and directly enhances efficacy. Example 5 showed little difference in efficacy compared to Comparative Example 1 without the addition of a photosynthesis promoter, indicating that the photosynthesis promoter mainly acts on plant health (beautiful leaves) rather than directly killing bacteria.

[0084] 2. Chlorophyll content test of melon leaves: The test site was located in Weifang City, Shandong Province, using the Crisp Pear variety. The pesticide was applied during the flowering period. Ten days after the application, functional leaves from the same leaf position were collected, and the chlorophyll a and b contents were determined by spectrophotometry using a mixture of acetone and ethanol.

[0085] The test results are shown in Table 4.

[0086] Table 4

[0087] Table 4 shows that the chlorophyll content data of melons in the examples containing photosynthesis promoters increased the chlorophyll content by 19.9%-29.9%. In particular, Example 5 had a chlorophyll content of 2.61 mg / g, which was 29.9% higher than the blank control of 2.01 mg / g, achieving a significant effect of brightening the leaves. The dark green leaves and enhanced photosynthesis lay the foundation for increased yield and improved quality.

[0088] Comparative Example 1, without the addition of a photosynthesis promoter, showed an improvement of only 5.5%, close to the blank control, indicating that the photosynthesis promoter is key to achieving the desired leaf enhancement effect. Comparative Example 3, with the addition of a physical mixture of chlorogenic acid and zinc sulfate as a photosynthesis promoter, showed an improvement of only 13.0%, far lower than the 29.9% in Example 5, demonstrating that the complexed form improved the stability of chlorogenic acid and the bioavailability of zinc ions, resulting in a significant synergistic effect. Comparative Example 2, without the addition of a penetration and spreading agent, showed an improvement of 15.4%, but a 47% decrease in effect. This indicates that the penetration and spreading agent not only promotes the penetration of the fungicide but also promotes the spreading and absorption of the photosynthesis promoter on the leaf surface, with both exhibiting a synergistic effect.

[0089] 3. Effect of improving apple rust spots: The test site was in Luochuan County, Shaanxi Province, using the Red Fuji variety. The pesticide was applied before bagging (30 days after flowering). At harvest, the rust spot index (0-9) of the fruit surface was investigated, and the gloss of the fruit surface and the percentage of marketable fruit were measured using a gloss meter.

[0090] The test results are shown in Table 5.

[0091] Table 5

[0092] As can be seen from the data on the improvement of apple rust spots in Table 5, Example 5 had a rust index of 1.7 and a marketable fruit rate of 93.1%, which was significantly better than the blank control (rust index 4.2 and marketable fruit rate 68.3%).

[0093] Comparative Example 1, without the addition of a photosynthesis promoter, had a fruit russeting index of 2.2, with fruit russeting severity increased by 22%. This indicates that the chlorogenic acid-zinc complex reduces fruit russeting by enhancing photosynthesis and improving fruit epidermal development. Comparative Example 2 (without a penetrating spreader) had a fruit russeting index of 2.7 and a marketable fruit rate of 84.2%, indicating that the penetrating spreader helps reduce fruit russeting by improving the spread of the pesticide solution and reducing localized pesticide accumulation. Comparative Example 4 had a fruit russeting index of 2.8; the larger the particle size, the more severe the fruit russeting. This may be because large-particle pesticide solutions spread unevenly, easily forming localized high-concentration spots on the fruit surface, stimulating fruit russeting formation.

[0094] The above are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A pyraclostrobin·bromodiphenyl ether emulsion, characterized in that, The water-in-oil emulsion comprises, by mass percentage: 8-12% pyraclostrobin, 16-24% bromodiphenyl ether, 10-18% solvent, 8-15% composite surfactant, 2-6% photosynthesis promoter, 3-8% penetrating spreader, 1-3% epichlorohydrin, 3-6% glycerol, 0.1-0.5% silicone defoamer, with the balance being water; the mass ratio of pyraclostrobin to bromodiphenyl ether is 1:2; the composite surfactant is a compound of phenethylphenol polyoxyethylene ether and calcium dodecylbenzenesulfonate in a mass ratio of 2.5-3.5:1; the photosynthesis promoter is a complex of chlorogenic acid and zinc ions in a molar ratio of 1:1; and the penetrating spreader is a composition of silicone-modified polyether and vegetable oleic acid in a mass ratio of 1.5-2.5:

1. The solvent is a mixture of cyclohexanone and Solvesso 200 in a volume ratio of 2-4:1; The preparation steps of the complex are as follows: Chlorogenic acid is added to water, heated to 50-60℃, and stirred until completely dissolved to prepare a 0.05-0.1 mol / L chlorogenic acid solution. Zinc sulfate is dissolved in water to prepare a 0.025-0.05 mol / L zinc salt solution. Under stirring at 300-400 rpm, the zinc salt solution is slowly added dropwise to the chlorogenic acid solution at a rate of 2-3 mL / min. The reaction temperature is maintained at 50-60℃, and the reaction is continuously stirred for 2-3 hours. Finally, the pH of the reaction solution is slowly adjusted to 5.5-6.5 with 0.1 mol / L dilute NaOH solution to obtain the complex. The organosilicon-modified polyether is polyether-modified heptamethyltrisiloxane, and the vegetable oleic acid is plant-derived oleic acid with an oleic acid content ≥75%. The preparation steps of the polyether-modified heptamethyltrisiloxane are as follows: heptamethyltrisiloxane and allyl polyether in a molar ratio of 1:1.05-1.1 are dissolved in toluene, added to a four-necked flask, protected by nitrogen, heated to 75-85℃, chloroplatinic acid catalyst is added, the temperature is raised to 110-115℃, and the reaction is carried out for 4-6 hours. After the reaction is completed, the solvent is removed by vacuum distillation, activated carbon is added for decolorization, the mixture is stirred at 55-65℃ for 25-35 minutes, and filtered to obtain the polyether-modified heptamethyltrisiloxane.

2. A method for preparing the pyraclostrobin·bromodiphenyl ether emulsion as described in any one of claims 1, characterized in that, The preparation method includes the following steps: (1) Preparation of oil phase: Weigh pyraclostrobin and bromodiphenyl ether according to the ratio, add them to the solvent, heat to 40-50℃ and stir to dissolve, then add the composite surfactant and stir evenly to obtain the oil phase; (2) Preparation of aqueous phase: Weigh the photosynthesis promoter, glycerol and some water according to the ratio, mix and stir until completely dissolved to obtain the aqueous phase; (3) Primary emulsification: Under high-speed shearing conditions, the aqueous phase is slowly added to the oil phase at a shearing speed of 2000-3000 rpm and a shearing time of 15-30 min to obtain a primary emulsion; (4) Homogenization and refinement: The primary emulsion is homogenized 1-3 times under a pressure of 30-50MPa using a high-pressure homogenizer; (5) Post-mixing: Add penetrating spreading agent, epichlorohydrin and organosilicon defoamer, stir and mix evenly, add the remaining water, continue stirring for 10-15 minutes, take a sample for testing and filter after passing the test, and you will get pyraclostrobin·bromodimethalin emulsion.

3. The application of a pyraclostrobin·bromodiflubenzuron water-in-oil emulsion in the control of anthracnose in fruit trees, melons, and vegetables, characterized in that, The pyraclostrobin-bromodiflubenzuron water emulsion is prepared using any one of the pyraclostrobin-bromodiflubenzuron water emulsions as described in claim 1, or the pyraclostrobin-bromodiflubenzuron water emulsion prepared by the method described in claim 2; the fruit trees are apples, pears, citrus, and mangoes; the melons are watermelons and cantaloupes; and the vegetables are eggplants and peppers.

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