Agricultural synergist containing citronellal and application thereof

Abstract

The invention discloses an agricultural synergist containing citronellal and application of the agricultural synergist, and belongs to the technical field of pesticides. According to the invention, a microemulsion system (5-20% of citronellal, 2-5% of a PEG-PCL nano-carrier and 1-5% of an organosilicon surfactant) is optimized, and high-pressure homogenization and ultrasonic processes are combined, so that the stable synergist with the particle size of 50-200nm and the pH value of 5.5-6.5 is prepared. The pesticide is compounded with chlorantraniliprole, deltamethrin or pymetrozine (in a ratio of 1: 4-1: 10), so that the toxicity to tetranychus urticae is remarkably enhanced, and the pesticide is superior to a single pesticide. According to the invention, controlled release is realized through the pH responsive nano-carrier, the pesticide effect is prolonged, and the pesticide application frequency is reduced; the environment-friendly dosage form (missible oil, suspending agent and the like) reduces the use of organic solvents, and has both high efficiency and environment friendliness. The method is suitable for various pests and crops, the process is simplified, the industrial potential is achieved, and an efficient solution is provided for sustainable agriculture.

Description

Technical Field

[0001] The invention belongs to the technical field of pesticides, and in particular relates to an agricultural synergist containing citronellal and application thereof. Background Art

[0002] With the continuous development of global agricultural production, pesticides play a vital role in ensuring crop yield and quality. However, traditional pesticides have exposed a series of problems during use, such as unstable efficacy, environmental pollution, and increased pest resistance. These problems seriously restrict the sustainable development of agriculture. To this end, pesticide synergists, as an important auxiliary means, are widely used to improve pesticide utilization efficiency, prolong the duration of efficacy, and reduce the frequency of application. However, existing pesticide synergists still have many shortcomings in practical application, and improvement and innovation are urgently needed. This section will analyze in detail the shortcomings of existing technologies in pesticide synergists, microemulsion systems, nanoparticle carriers, insecticide compounding, and dosage form design, providing a basis for subsequent technological improvements.

[0003] Traditional pesticide synergists are mostly based on surfactants or adjuvants, and their core function is to improve the dispersibility, adhesion and permeability of pesticides. Although these synergists have improved the performance of pesticides to a certain extent, they still expose the following significant problems in actual application: Poor stability. Traditional synergists are easily affected by environmental factors (such as temperature, pH value, and light), resulting in unstable synergistic effects. For example, certain surfactants are prone to decomposition and loss of activity under high temperature or acidic conditions, thereby weakening the efficacy of pesticides. This instability is particularly prominent in complex and changeable field environments, limiting the reliability and practicality of synergists. Poor particle size control. Traditional preparation methods make it difficult to accurately control the particle size of synergists, resulting in uneven particle size distribution, which in turn affects the uniform release of efficacy. Excessively large particle size will significantly reduce the permeability of pesticides, making it difficult for them to penetrate the epidermis of pests or the cuticle of plant leaves, directly affecting the control effect. Insufficient particle size control has become a key bottleneck in the improvement of traditional synergist technology. Insufficient persistence of efficacy Traditional synergists cannot effectively extend the efficacy of pesticides, and the pesticides after application are often quickly degraded or lost by the environment. In order to maintain the control effect, farmers have to apply pesticides frequently, which not only increases the cost of agricultural production, but also increases the environmental burden, such as soil and water pollution. The lack of persistence of efficacy is one of the core problems that need to be urgently solved by current pesticide synergists. Poor environmental adaptability Existing synergists have limited adaptability to different crops and pests, making it difficult to achieve broad-spectrum application. For example, some synergists perform well on specific crops (such as rice), but are not effective on other crops (such as fruit trees). This limitation restricts the promotion and application of synergists, making it difficult to meet the diversified needs of modern agriculture.

[0004] In recent years, some studies have attempted to improve the performance of synergists through nanotechnology. However, existing nanosynergists are mostly single nanomaterials and still suffer from the following limitations: Low encapsulation efficiency. Existing nanocarriers generally have a low encapsulation efficiency for pesticide active ingredients, typically only 60-80%. This results in a large amount of pesticide not being effectively utilized, resulting in loss of efficacy and waste of resources. Imprecise release control. Existing nanosynergists have difficulty achieving intelligent release based on environmental conditions (such as temperature, humidity, and pH), resulting in low efficacy utilization and difficulty meeting the needs of precision application. This limitation in release control limits the potential of nanotechnology in pesticide synergism. Complex preparation process. Existing nanocarriers are mostly prepared using methods such as high-pressure homogenization or ultrasonic emulsification, which have low production efficiency and complex processes, making large-scale industrial production difficult. This further hinders the widespread application of nanosynergists in the agricultural field. Microemulsion systems have been widely used in pesticide formulations due to their small particle size and good stability. However, the performance of traditional microemulsion systems in pesticide synergism remains unsatisfactory. Key issues include: Large particle size. Traditional microemulsions typically range from 100 to 500 nm, resulting in insufficient permeability and difficulty effectively penetrating the pest cuticle or plant cuticle, leading to low pesticide absorption and utilization efficiency. This large particle size is a key issue in microemulsion systems that urgently needs to be optimized. Poor stability. Traditional microemulsions are prone to demulsification and coagulation during storage and transportation, seriously impacting their effectiveness. Once demulsified, the microemulsion loses its original synergistic function and may even cause crop damage. This stability issue limits the practical application value of microemulsion systems. Inappropriate component ratios. To maintain system stability, high concentrations of surfactants are often used in traditional microemulsion preparation. However, high surfactant concentrations can negatively impact the environment and crops, such as soil contamination and phytotoxicity. This inappropriate component ratio raises questions about the environmental friendliness of traditional microemulsions. Furthermore, the application of existing microemulsion systems in pesticide synergism is largely limited to improving dispersibility, failing to fully leverage the advantages of nanotechnology, such as controlled release and targeted delivery. This has resulted in the potential of microemulsion systems in modern agriculture not being fully tapped.

[0005] Nanoparticle carriers hold great promise for controlled-release and enhanced pesticide synergy, but their application is still immature and faces the following technical challenges: Improper polymer selection: Existing nanocarriers often use non-responsive polymers, making it difficult to achieve environmentally responsive release, resulting in imprecise pesticide release and low efficacy utilization. For example, the release rate lacks variability under different environmental conditions, making it unable to adapt to the complexity of field environments. Imprecise preparation methods: Traditional preparation methods struggle to precisely control the particle size and zeta potential of nanoparticles, resulting in poor stability and prone to aggregation or sedimentation, which affects their effectiveness in pesticide formulations. Low encapsulation efficiency: Existing nanocarriers generally have low encapsulation efficiencies for active ingredients, ranging from 60% to 80%. This results in a significant amount of pesticide not being effectively encapsulated, resulting in waste and increased production costs. Furthermore, existing nanoparticle carriers have limited functionality, making it difficult to simultaneously achieve controlled-release, enhanced synergy, and environmental adaptability, limiting their potential for pesticide synergy enhancement.

[0006] For highly resistant pests such as the two-spotted spider mite (Tetranych usurticae), existing insecticide compounding technologies have the following problems: Increased resistance: Long-term use of insecticides with a single active ingredient leads to significantly increased pest resistance and reduced control effectiveness. For example, the two-spotted spider mite has developed a high degree of resistance to a variety of traditional insecticides, making it difficult to effectively control it with a single pesticide. Poor compatibility: Existing compounding solutions are mostly simple mixtures, and there may be antagonism between different active ingredients, which in turn reduces the efficacy of the drugs. For example, some compounding schemes fail to achieve synergistic effects and even show a weakening of the drug efficacy. Unscientific compounding ratios: Existing compounding schemes lack systematic research, and compounding ratios are mostly determined empirically, resulting in unstable effects and difficulty in achieving the best control effect. Lack of targeting: Existing compounding schemes are mostly broad-spectrum insecticides, which make it difficult to accurately control specific pests such as the two-spotted spider mite, and may also have an impact on non-target organisms, disrupting the ecological balance. Existing pesticide formulations (such as emulsifiable concentrates and suspension concentrates) have the following problems in actual application: Environmental pollution. Emulsifiable concentrate formulations contain a large amount of organic solvents (such as toluene and xylene), which pose a threat to the environment and human health and can easily cause soil and water pollution. Inconvenient application of pesticides. Suspension concentrates can easily clog nozzles, affecting the efficiency of application and increasing the labor intensity of farmers. Uneven release of drug efficacy. Traditional formulations are difficult to achieve uniform release of drug efficacy, resulting in uneven distribution of drug efficacy. The drug efficacy in some areas is too strong or too weak, affecting the prevention and control effect. In addition, existing formulations have limitations in adapting to different crops and pests, and it is difficult to meet the needs of modern agriculture for efficient, environmentally friendly and precise application of pesticides.

[0007] In summary, existing pesticide synergists have significant deficiencies in stability, particle size control, sustained efficacy, and environmental adaptability. The application of microemulsion systems and nanoparticle carriers in pesticide synergism faces technical bottlenecks. Combination pesticide formulations have limited effectiveness against pesticide-resistant pests such as spider mites. Traditional formulation designs also pose environmental pollution and inconvenient application. Therefore, developing a new agricultural synergist to address these technical deficiencies and enhance pesticide efficacy is of great practical significance and application value. Summary of the Invention

[0008] 1. Problems to be solved

[0009] In response to the problems existing in the above-mentioned prior art, the present invention aims to solve the key technical bottlenecks mentioned in the above background technology, so as to improve the performance, insecticidal effect and environmental adaptability of pesticide synergists and promote the development of sustainable agriculture.

[0010] 2. Technical solution

[0011] To solve the above problems, the present invention adopts the following technical solutions.

[0012] A citronellal-containing agricultural synergist comprises the following components in percentage by weight: 5-20% citronellal (CAS No. 5392-40-5), 5-15% fatty alcohol polyoxyethylene ether (CAS No. 68439-50-9), 3-8% alkyl glycoside (CAS No. 110615-47-9), 2-5% nanoparticle carrier, 1-5% organosilicon surfactant, and the balance is deionized water. The synergist forms a microemulsion system with a particle size of 50-200 nm and a pH value of 5.5-6.5.

[0013] Preferably, the preparation method of the nanoparticle carrier is as follows: PEG-PCL (CAS No. 34364-83-5) and phenylboronic acid pinacol ester (CAS No. 24388-23-6) are dissolved in tetrahydrofuran (CAS No. 109-99-9) with a mass ratio of 2:(2-6) to prepare an organic phase solution; an aqueous phase solution containing 2-4 mM sodium phosphate is prepared; the organic phase solution and the aqueous phase solution are mixed by a vortex mixer, wherein the volume ratio between the organic phase solution and the aqueous phase solution is 2:(5-10), and then diluted ten times the volume with physiological saline. After dilution, the mixture is heated to 80-90°C and oil bathed for 40-60 minutes, the precipitate is recovered by centrifugation at 12000 rpm, and vacuum freeze-dried to obtain the nanoparticle carrier.

[0014] Preferably, the organosilicon surfactant is polydimethylsiloxane (CAS No. 63148-62-9), polymethylhydrogensiloxane (CAS No. 63148-57-2), polyether-modified polysiloxane (CAS No. 68937-54-2) or amino-modified polysiloxane (CAS No. 71750-80-6).

[0015] Preferably, the preparation method of the agricultural synergist is as follows: fatty alcohol polyoxyethylene ether, alkyl glycoside, and silicone surfactant are added in proportion to deionized water with three-quarters of the mass removed, and stirred at 40-45°C until completely dissolved to obtain a mixed solution; citronellal is slowly added to the mixed solution under stirring conditions of 200-400 rpm, and the addition rate is controlled to be ≤5 mL / min to form a primary emulsion; the nanoparticle carrier is heated to 60°C at a rate of 0.5°C / min, dispersed in the remaining deionized water, ultrasonically treated, and then added to the primary emulsion, and subjected to high-pressure homogenization to obtain a microemulsion with a particle size of 50-200 nm, the pH is adjusted to 5.5-6.5, and the mixture is filtered, sterilized, and then filled.

[0016] Preferably, the parameters of ultrasonic treatment are as follows: 20-30 kHz, 150-200 W and 10-15 min; the parameters of high-pressure homogenization are as follows: 800-1200 bar, 3 times and below 35°C.

[0017] The agricultural synergist containing citronellal as described above is used in the preparation of insecticides.

[0018] Preferably, the agricultural synergist is compounded with an insecticide in a mass ratio of 1:(4-10); the insecticide is selected from at least one of chlorantraniliprole, deltamethrin and pymetrozine.

[0019] Preferably, the dosage form of the agricultural synergist is a pharmaceutically acceptable dosage form, including but not limited to emulsifiable concentrate, suspension, water dispersible granules or soluble powder.

[0020] Preferably, the pest controlled by the insecticide is two-spotted spider mite, whose Latin name is Tetranychus urticae.

[0021] 3. Beneficial effects

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) Significantly improve the toxicity and synergistic effect of insecticides

[0024] The present invention optimizes the formulation of a citronellal-containing agricultural synergist (5-20% citronellal, 2-5% nanoparticle carrier, 1-5% organosilicon surfactant, etc.) and combines it with an insecticide (chlorfenapyr, deltamethrin, or pymetrozine) to significantly enhance its toxicity against two-spotted spider mites (Tetranychus urticae). Indoor toxicity testing showed that Example 1 (12% citronellal, 1:7 compounding ratio) achieved a 98.5% corrected mortality rate on day 5 at 4.0 mg / L chlorfenapyr, with an LC50 of only 0.78 mg / L (95% CI: 0.65-0.93). The synergistic coefficient (CTC) reached 192.3, far superior to chlorfenapyr alone (78.5% mortality, LC50 = 1.50 mg / L, CTC = 100). Compared with the additive effect of traditional synergists in the prior art (CTC80-120), the present invention achieves significant synergistic synergy, overcomes the problem of increased resistance of pests to pesticides, and is particularly suitable for the control of highly resistant spider mites.

[0025] (2) Optimized microemulsion system stability and permeability

[0026] The present invention significantly improves the stability and permeability of the synergist by precisely controlling the particle size (50-200nm) and pH (5.5-6.5) of the microemulsion system. The microemulsion systems of Examples 1-10 remain stable during storage and field environments, avoiding the defects of traditional microemulsion systems that are prone to demulsification and coagulation (the mortality rates of Comparative Examples 3 and 16 are only 82.4%-82.9%, and the LC50 is as high as 1.60-1.62mg / L). The synergistic effect of the nanoparticle carrier (PEG-PCL and phenylboronic acid pinacol ester 2:2-2:6) and the organosilicon surfactant (polyether-modified polysiloxane, etc.) enhances the permeability of the pesticide in the epidermis of pests and the cuticle of plant leaves. The present invention has better permeability and stability in the field of pesticide synergism, and its high efficiency is verified by the mortality rate and LC50 data.

[0027] (3) Prolonging drug efficacy and controlled release performance

[0028] The present invention uses PEG-PCL nanoparticle carriers to achieve controlled release of citronellal and insecticides through pH responsive design (pH 5.5-6.5 adapted to the field environment), significantly extending the duration of efficacy. Test results show that Examples 1-10 still maintained a corrected mortality rate of 92.3%-98.5% on the 5th day, while Comparative Example 3 (without nanocarriers) was only 82.4%, indicating that nanocarriers effectively reduce the degradation and loss of active ingredients. Compared with the traditional synergists in the prior art that have insufficient efficacy persistence (frequent application is required), the present invention reduces the frequency of application, reduces agricultural production costs and environmental pollution, and meets the needs of sustainable agriculture.

[0029] (4) Environmental friendliness and safety

[0030] The present invention reduces the use of organic solvents (such as toluene and xylene) in traditional emulsifiable concentrate formulations by optimizing the component ratio (5-20% citronellal, low surfactant content) and environmentally friendly formulations (emulsifiable concentrate, suspension concentrate, water-dispersible granules, soluble powders), thereby reducing the risk of soil and water pollution. Comparative Example 6 (10% alkyl glycoside) and Comparative Example 2 (25% citronellal) have potential environmental toxicity due to high concentrations of surfactants or active ingredients, while the formulations of Examples 1-10 maintain environmental friendliness while being highly effective. In addition, the precise compounding ratio (1:4-1:10) avoids antagonistic effects (such as Comparative Examples 13 and 14, the CT C is only 104.9-106.4), reduces the impact on non-target organisms, and protects the ecological balance.

[0031] (5) Broad-spectrum adaptability and dosage form diversity

[0032] The synergist of the present invention is applicable to a variety of insecticides (chlorfenapyr, deltamethrin, pymetrozine) and a variety of formulations (emulsifiable concentrates, suspensions, etc.), and can target a variety of crop pests such as spider mites, overcoming the limitations of existing synergists in their poor adaptability to different crops and pests. Test results show that Example 2 (deltamethrin compound) and Example 3 (pymetrozine compound) all exhibited high mortality (92.3%-94.7%) and low LC50 (0.92-1.05 mg / L), verifying their broad-spectrum application potential. Compared with traditional technologies, the present invention is more effective in the prevention and control of spider mites, and the diversity of formulations facilitates field application, reduces the problem of nozzle clogging, and improves application efficiency.

[0033] (6) Simplified preparation process and industrialization potential

[0034] The present invention optimizes the preparation process (ultrasound 20-30kHz, homogenization 800-1200bar, citronellal addition rate ≤ 5mL / min), ensuring that the microemulsion particle size is uniform (50-200nm) and the production efficiency is high. Comparative Examples 10-12 (addition rate 10mL / min, ultrasound 15kHz, homogenization 600bar) have uneven particle sizes (>200nm) due to process deviation, and the mortality rate and LC50 are significantly inferior to those of the examples. The process parameters of the present invention (such as oil bath 50min, 12000rpm centrifugation) simplify the nanocarrier preparation process and have higher industrial production feasibility than the complex high-pressure homogenization or ultrasonic emulsification methods in the prior art.

[0035] (7) Overcoming existing technological bottlenecks

[0036] Stability: The problem of traditional synergists being affected by environmental factors (temperature, pH, light) and decomposition is solved. Examples 1-10 maintain high stability under field simulation conditions (25±1°C, RH 70±5%).

[0037] Particle size control: Achieve a particle size of 50-200nm through nano-carriers and high-pressure homogenization technology, which is superior to traditional microemulsions (100-500nm), improving permeability and drug efficacy uniformity.

[0038] Encapsulation efficiency: The encapsulation rate of PEG-PCL nanocarriers reaches 85-90% (better than the 60-80% of the existing technology), reducing the waste of active ingredients.

[0039] Targetedness: Aiming at the problem of drug resistance of two-spotted spider mites, the optimized compound ratio (1:4-1:10) ensures synergistic effect and overcomes the antagonistic effect of existing compound schemes (such as comparative examples 13 and 14). BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 1 is a transmission electron micrograph of the emulsifiable concentrate formulation prepared in Example 1. DETAILED DESCRIPTION

[0041] The present invention is described in detail below through specific examples. However, the use and purpose of these exemplary embodiments are merely illustrative of the present invention and are not intended to limit the actual scope of protection of the present invention in any form, nor are they intended to limit the scope of protection of the present invention to these examples. For parameter ranges not mentioned, intermediate values ​​are selected. In addition, for mass percentages or weight percentages not explicitly stated or mentioned, they generally refer to the final concentration after addition.

[0042] Example 1

[0043] An agricultural synergist containing citronellal was prepared. The specific components and preparation method are as follows: Components (by weight): citronellal: 12%, fatty alcohol polyoxyethylene ether: 10%, alkyl glycoside: 5%, nanoparticle carrier: 3%, silicone surfactant (polyether-modified polysiloxane): 3%, and the balance is deionized water. To prepare the nanoparticle carrier, PEG-PCL (CAS No. 34364-83-5) and phenylboronic acid pinacol ester (in a mass ratio of 2:4) were dissolved in tetrahydrofuran (15 times the mass of phenylboronic acid pinacol ester) to prepare an organic phase solution. An aqueous phase solution containing 3 mM sodium phosphate was prepared. The organic and aqueous phases were mixed in a vortex mixer at a volume ratio of 2:7.5. After mixing, the mixture was diluted tenfold with physiological saline, heated to 85°C, and in an oil bath for 50 minutes. The precipitate was recovered by centrifugation at 12,000 rpm and freeze-dried in a vacuum oven to obtain the nanoparticle carrier. Preparation of synergist: Add fatty alcohol polyoxyethylene ether, alkyl glycoside and polyether modified polysiloxane to three-quarters of the mass of deionized water in proportion, stir at 42°C until completely dissolved to obtain a mixed solution. Under stirring at 300rpm, slowly add citronellal at a rate of 3mL / min to form a primary emulsion. Heat the nanoparticle carrier to 60°C at a rate of 0.5°C / min, disperse it in the remaining deionized water, ultrasonically treat (25kHz, 175W, 12min), and add the primary emulsion. High-pressure homogenization treatment (1000bar, 3 times, 30°C) is performed to obtain a microemulsion with a particle size of 50-200nm, adjust the pH to 6.0, filter and sterilize, and then fill. Application: Compound the above-mentioned synergist with chlorantraniliprole at a mass ratio of 1:7 to prepare an emulsifiable concentrate formulation (such as Figure 1 As shown), it is used to control two-spotted spider mites (Tetranych usurtica e).

[0044] Example 2

[0045] A citronellal-containing agricultural synergist was prepared. The ingredients (by weight percentage) were: citronellal: 5%, fatty alcohol polyoxyethylene ether: 15%, alkyl glycoside: 3%, nanoparticle carrier: 5%, organosilicon surfactant (polydimethylsiloxane): 1%, and the balance was deionized water. To prepare the nanoparticle carrier, PEG-PCL and phenylboronic acid pinacol ester were dissolved in tetrahydrofuran (10 times the mass of phenylboronic acid pinacol ester) at a mass ratio of 2:2. The organic phase was prepared. The aqueous phase contained 2 mM sodium phosphate, and the organic phase to aqueous phase ratio was 2:5. The mixture was diluted, incubated in an 80°C oil bath for 40 minutes, centrifuged at 12,000 rpm, and freeze-dried. To prepare the synergist, the surfactant was added to three-quarters of deionized water and dissolved with stirring at 40°C. Stirring was performed at 200 rpm, and citronellal was added at a rate of 2 mL / min to form a primary emulsion. The nanoparticle carrier was heated to 60°C and ultrasonically treated (20 kHz, 150 W, 10 min). The emulsion was then added and high-pressure homogenized (800 bar, 3 times, 32°C). The pH was adjusted to 5.5 and the suspension was sterilized by filtration. Application: The synergist and deltamethrin were combined in a ratio of 1:4 to prepare a suspension concentrate for the control of spider mites.

[0046] Example 3

[0047] A citronellal-containing agricultural synergist was prepared. The following components (by weight percentage) were used: citronellal: 20%, fatty alcohol polyoxyethylene ether: 5%, alkyl glycoside: 8%, nanoparticle carrier: 2%, silicone surfactant (amino-modified polysiloxane): 5%, and the balance was deionized water. To prepare the nanoparticle carrier, PEG-PCL and phenylboronic acid pinacol ester were dissolved in 20% tetrahydrofuran at a ratio of 2:6. The aqueous phase contained 4 mM sodium phosphate in a volume ratio of 2:10. The mixture was incubated in an oil bath at 90°C for 60 minutes, centrifuged at 12,000 rpm, and freeze-dried. To prepare the synergist, the surfactant was dissolved at 40°C with stirring at 400 rpm. Citronellal was added at a rate of 5 mL / min. The nanoparticle carrier was dispersed at 60°C, sonicated (30 kHz, 200 W, 15 minutes), and homogenized under high pressure (1200 bar, three times, 35°C). The pH was adjusted to 6.5, and the mixture was sterilized by filtration. Application: The synergist is mixed with pymetrozine at a ratio of 1:10 to prepare water-dispersible granules for the control of spider mites.

[0048] Examples 4-10 adjust some parameters based on Example 1 to maintain the scope of the claim, as follows: Example 4: 8% citronellal, 12% fatty alcohol polyoxyethylene ether, 4% alkyl glycoside, 4% nanoparticle carrier, 2% polymethylhydrogen siloxane, pH 5.8, compounded with chlorantraniliprole (1:6) to prepare a soluble powder. Example 5: 15% citronellal, 8% fatty alcohol polyoxyethylene ether, 6% alkyl glycoside, 3% nanoparticle carrier, 4% polyether-modified polysiloxane, pH 6.0, compounded with deltamethrin (1:8) to prepare an emulsifiable concentrate. Example 6: 10% citronellal, 10% fatty alcohol polyoxyethylene ether, 5% alkyl glycoside, 2.5% nanoparticle carrier, 3% polydimethylsiloxane, pH 6.2, compounded with pymetrozine (1:5) to prepare a suspension. Example 7: 18% citronellal, 7% fatty alcohol polyoxyethylene ether, 7% alkyl glycoside, 4.5% nanoparticle carrier, 2% amino-modified polysiloxane, pH 5.7, compounded with chlorantraniliprole (1:9) to prepare a water-dispersible granule. Example 8: 6% citronellal, 14% fatty alcohol polyoxyethylene ether, 3.5% alkyl glycoside, 3.5% nanoparticle carrier, 1.5% polyether-modified polysiloxane, pH 6.3, compounded with deltamethrin (1:7) to prepare an emulsifiable concentrate. Example 9: 13% citronellal, 9% fatty alcohol polyoxyethylene ether, 6.5% alkyl glycoside, 2.8% nanoparticle carrier, 4% polymethylhydrogensiloxane, pH 5.9, compounded with pymetrozine (1:6) to prepare a suspension concentrate. Example 10: A soluble powder was prepared by mixing 17% citronellal, 6% fatty alcohol polyoxyethylene ether, 4.5% alkyl glycoside, 4% nanoparticle carrier, 2.5% polydimethylsiloxane, and chlorantraniliprole (1:8) at pH 6.1. Preparation process: Similar to Example 1, except that the ultrasonic treatment (20-30 kHz, 150-200 W, 10-15 min) and high-pressure homogenization (800-1200 bar, 3 times, 30-35° C.) parameters were adjusted to intermediate values.

[0049] Comparative Examples 1-16 deviate from the scope of the claims by changing the components, proportions, or preparation process parameters, highlighting the advantages of the embodiments. The following is a detailed description: Comparative Example 1: 3% citronellal (below the scope of the claims), other components are the same as in Example 1, the preparation process remains unchanged, and chlorantraniliprole (1:7) is compounded to prepare an emulsifiable concentrate. Comparative Example 2: 25% citronellal (above the scope), other components are the same as in Example 1, the preparation process remains unchanged, and chlorantraniliprole (1:7) is compounded to prepare an emulsifiable concentrate. Comparative Example 3: No nanoparticle carrier, 12% citronellal, 13% fatty alcohol polyoxyethylene ether, 5% alkyl glycoside, 3% polyether-modified polysiloxane, the process is the same as in Example 1, and chlorantraniliprole (1:7) is compounded. Comparative Example 4: 7% nanoparticle carrier (above the scope), 12% citronellal, 8% fatty alcohol polyoxyethylene ether, 3% alkyl glycoside, 2% polyether-modified polysiloxane, the process is the same as in Example 1, and chlorantraniliprole (1:7) is compounded. Comparative Example 5: Fatty alcohol polyoxyethylene ether 3% (below the range), citronellal 12%, other processes same as Example 1, compound chlorantraniliprole (1:7). Comparative Example 6: Alkyl glycoside 10% (above the range), citronellal 12%, other processes same as Example 1, compound chlorantraniliprole (1:7). Comparative Example 7: Silicone surfactant 0.5% (below the range), citronellal 12%, other processes same as Example 1, compound chlorantraniliprole (1:7). Comparative Example 8: pH 5.0 (below the range), other processes same as Example 1, compound chlorantraniliprole (1:7). Comparative Example 9: pH 7.0 (above the range), other processes same as Example 1, compound chlorantraniliprole (1:7). Comparative Example 10: Citronellal addition rate 10 mL / min (above the range), other processes same as Example 1, compound chlorantraniliprole (1:7). Comparative Example 11: Ultrasonic treatment at 15 kHz (below the range), 150 W, 10 min, otherwise the same as Example 1, compounding chlorantraniliprole (1:7). Comparative Example 12: High-pressure homogenization at 600 bar (below the range), 3 times, 30°C, otherwise the same as Example 1, compounding chlorantraniliprole (1:7). Comparative Example 13: Compounding ratio 1:3 (below the range), otherwise the same as Example 1, preparing an emulsifiable concentrate. Comparative Example 14: Compounding ratio 1:12 (above the range), otherwise the same as Example 1, preparing an emulsifiable concentrate. Comparative Example 15: In the preparation of nanoparticle carriers, the mass ratio of PEG-PCL to phenylboronic acid pinacol ester was 2:8 (above the range), otherwise the same as Example 1, compounding chlorantraniliprole (1:7). Comparative Example 16: Without the use of silicone surfactant, 12% citronellal, 13% fatty alcohol polyoxyethylene ether, 5% alkyl glycoside, 3% nanoparticle carrier, the process was the same as Example 1, compounding chlorantraniliprole (1:7).

[0050] Test Method

[0051] (1) Indoor toxicity test method

[0052] Objective: To determine the toxicity of the citronellal-containing agricultural synergists in Examples 1-10 and Comparative Examples 1-16 mixed with insecticides (chlorantraniliprole, deltamethrin, or pymetrozine) against Tetranychus urticae, and to calculate the mortality rate, toxicity regression equation, and LC50.

[0053] Test insect preparation

[0054] Test insects: Two-spotted spider mite (Tetranych usurticae), raised indoors, female adult mites, uniform in size and good in vitality.

[0055] Rearing conditions: temperature 25±1℃, relative humidity 70±5%, photoperiod 16L:8D, reared on cowpea (Vigna unguiculata) leaves.

[0056] Inoculation: 100 female adult mites were selected for each treatment, repeated 3 times, with a total of 300 mites per treatment.

[0057] Pharmaceutical preparation

[0058] Examples 1-10: A synergist (citronellal 5-20%, fatty alcohol polyoxyethylene ether 5-15%, alkyl glycoside 3-8%, nanoparticle carrier 2-5%, silicone surfactant 1-5%, pH 5.5-6.5) was prepared according to a specific embodiment and compounded with an insecticide (chlorfenapyr, deltamethrin or pymetrozine) in a mass ratio of 1:4-1:10 to prepare an emulsifiable concentrate, a suspension concentrate, a water-dispersible granule or a soluble powder.

[0059] Comparative Examples 1-16: The components or process parameters were adjusted according to the specific implementation methods, deviating from the scope of the claims, and the compounding ratio and dosage form were consistent with the corresponding examples.

[0060] Concentration gradient: Calculate the active ingredient of chlorantraniliprole (or deltamethrin, pymetrozine) at five concentration gradients (0.5, 1.0, 2.0, 4.0, and 8.0 mg / L). Deionized water was used as the control. The synergist and insecticide were prepared at a fixed ratio (e.g., 1:7 in Example 1).

[0061] Dilution: Dilute to the required concentration with 0.1% Tween-80 aqueous solution to ensure uniform dispersion of the microemulsion system.

[0062] Application method

[0063] Leaf Dip Method (referring to FAO standards): Dip 5 cm diameter cowpea leaves into the solution for 10 seconds, remove, and air dry. Place the treated leaves in a Petri dish (containing moist filter paper) and inoculate 20 adult female mites per dish. Place the Petri dishes in a constant temperature incubator (25 ± 1°C, RH 70 ± 5%, 16 L:8 D). Application Rate: Cover each leaf evenly with the solution, approximately 0.1 mL / leaf.

[0064] Observation and recording

[0065] Observation time: Observe the death of two-spotted spider mites on the 1st, 3rd, 5th and 7th day after application.

[0066] Death determination: Use a fine-bristled brush to gently touch the mite body. If there is no reaction or only slight movement of the feet, it is considered dead. Replication: Repeat 3 times for each concentration, with 20 mites per replicate, for a total of 60 mites per concentration.

[0067] Data processing

[0068] Toxicity regression equation: SPSS26.0 software was used to fit the linear regression equation, with the concentration of the active ingredient of the insecticide (mg / L) as the independent variable (x) and the Probit value of the adjusted mortality rate as the dependent variable (y).

[0069] LC50 calculation: According to the regression equation, the 50% lethal concentration (LC50, mg / L) was calculated and the 95% confidence interval was determined.

[0070] Synergistic effect evaluation: Compare the LC50 and the 5-day corrected mortality of the examples and comparative examples to evaluate the synergistic effect and calculate the synergistic coefficient (CTC). CTC>120: significant synergistic effect, 80≤CTC≤120: additive effect, CTC<80: antagonistic effect.

[0071] (2) Test results

[0072] The following are the test results for Examples 1-10 and Comparative Examples 1-16, based on indoor toxicity testing, focusing on the 5-day corrected mortality rate, toxicity regression equation, LC50, and CTC. The results were similar for other insecticides (deltamethrin and pymetrozine) using chlorantraniliprole as the primary insecticide (with a 1:7 ratio as in Example 1). Only representative data from Example 1 and some comparative examples are listed. For simplicity, the table integrates key indicators, and detailed mortality data are listed by concentration gradient.

[0073] Table 1 Results table

[0074]

[0075]

[0076]

[0077]

[0078]

[0079] As shown in Table 1, AEO: fatty alcohol polyoxyethylene ether; APG: alkyl polyglycoside. Day 5 corrected mortality: Calculated at 4.0 mg / L chlorantraniliprole, reflects the toxicity of the compound formulation. LC50: Lower values ​​indicate greater toxicity, with Example 1 having the lowest value (0.78 mg / L), outperforming both the comparative examples and the single insecticide. CTC: Examples 1-10 all showed >120, indicating significant synergistic effects; the comparative examples mostly showed additive effects (80-120), with some (such as Comparative Examples 3, 9, and 16) approaching antagonism (<100).

[0080] Detailed mortality data (Example 1 and representative comparative examples)

[0081] The following is the adjusted mortality (%) on the 5th day for Example 1, Comparative Example 3 (without nanocarriers), Comparative Example 16 (without silicone), and chlorantraniliprole alone at 5 concentrations:

[0082] Table 2 Results table

[0083]

[0084]

[0085] As shown in Table 2, the following analysis shows that Example 1 achieved a mortality rate of 98.5% at 4.0 mg / L, significantly higher than 78.5% for chlorantraniliprole alone, demonstrating that the citronellal synergist enhanced permeability and sustained efficacy. Comparative Example 3: The absence of a nanocarrier resulted in larger particle size (>200 nm), decreased permeability, and a mortality rate of only 82.4%. Comparative Example 16: The absence of a silicone surfactant reduced microemulsion stability, resulting in a mortality rate slightly higher than that of Comparative Example 3 but significantly lower than that of Example 1.

[0086] Embodiment 1 (best embodiment):

[0087] Mortality: 98.5% (4.0 mg / L), the highest, indicating that the ratio of 12% citronellal, 3% nanocarrier and 3% polyether modified polysiloxane optimizes the microemulsion stability (50-200 nm) and permeability. LC50: 0.78 mg / L, the lowest, the strongest toxicity. CTC: 192.3, significant synergistic effect, attributed to the nanocarrier improving the controlled release of citronellal and the surfactant enhancing leaf attachment. Examples 2-10: Mortality (92.3%-95.4%) and LC50 (0.88-1.05 mg / L) are better than the control example, CTC>120, indicating that the ratio and process parameters within the scope of the claims are effective. Examples 5 (15% citronellal) and 9 (13% citronellal) have effects close to Example 1, indicating that 10-15% citronellal is a better concentration. Comparative Examples 1-16: Component Deviation (Comparative Examples 1-7, 15-16): Citronellal is too low (3%) or too high (25%), there is no nanocarrier, there is no silicone, etc., resulting in uneven microemulsion particle size (>200nm) or decreased stability, reduced mortality (82.4%-87.6%), increased LC50 (1.33-1.62 mg / L), and CTC close to additive effect. Process Deviation (Comparative Examples 8-12): pH, ultrasonic frequency, and homogenization pressure deviate from the range and affect the emulsification effect. The mortality rate and LC50 are inferior to the examples. Compound ratio deviation (Comparative Examples 13-14): 1:3 or 1:12 reduces synergistic synergy, and CTC is only 104.9-106.4.

[0088] The above content is a further detailed description of the present invention in conjunction with specific implementation methods. It cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, they can make several simple deductions or substitutions without departing from the concept of the present invention, which should be regarded as falling within the scope of protection determined by the claims submitted for the present invention.

Claims

1. An agricultural synergist containing citronellal, characterized in that: The invention comprises the following components in percentage by weight: 5-20% citronellal, 5-15% fatty alcohol polyoxyethylene ether, 3-8% alkyl glycoside, 2-5% nanoparticle carrier, 1-5% organosilicon surfactant, and the balance is deionized water; the synergist forms a microemulsion system with a particle size of 50-200 nm and a pH value of 5.5-6.

5.

2. The agricultural synergist containing citronellal according to claim 1, characterized in that: The preparation method of the nanoparticle carrier is as follows: PEG-PCL with CAS number 34364-83-5 and phenylboronic acid pinacol ester are dissolved in tetrahydrofuran with a mass ratio of 2:(2-6) in an amount 10-20 times the mass of the phenylboronic acid pinacol ester to prepare an organic phase solution; an aqueous phase solution containing 2-4 mM sodium phosphate is prepared; the organic phase solution and the aqueous phase solution are mixed by a vortex mixer, wherein the volume ratio between the organic phase solution and the aqueous phase solution is 2:(5-10); then, the mixture is diluted ten times its volume with physiological saline; after dilution, the mixture is heated to 80-90°C and placed in an oil bath for 40-60 minutes; the precipitate is recovered by centrifugation at 12000 rpm; and vacuum freeze-dried to obtain the nanoparticle carrier.

3. The agricultural synergist containing citronellal according to claim 1, characterized in that: The organic silicon surfactant is polydimethylsiloxane, polymethyl hydrogensiloxane, polyether modified polysiloxane or amino modified polysiloxane.

4. The agricultural synergist containing citronellal according to claim 1, characterized in that: The preparation method of the agricultural synergist is as follows: fatty alcohol polyoxyethylene ether, alkyl glycoside, and silicone surfactant are added in proportion to deionized water (removing three-quarters of its mass), and stirred at 40-45°C until completely dissolved to obtain a mixed solution; citronellal is slowly added to the mixed solution under stirring conditions of 200-400 rpm, with the addition rate controlled to be ≤5 mL / min, to form a primary emulsion; the nanoparticle carrier is heated to 60°C at a rate of 0.5°C / min, dispersed in the remaining deionized water, ultrasonically treated, and then added to the primary emulsion, subjected to high-pressure homogenization to obtain a microemulsion with a particle size of 50-200 nm, the pH is adjusted to 5.5-6.5, and the mixture is filtered, sterilized, and then filled.

5. The agricultural synergist containing citronellal according to claim 4, characterized in that: The parameters of ultrasonic treatment are as follows: 20-30 kHz, 150-200 W and 10-15 min; the parameters of high-pressure homogenization are as follows: 800-1200 bar, 3 times and below 35°C.

6. Use of the agricultural synergist containing citronellal according to any one of claims 1 to 5 in the preparation of insecticides.

7. The use of the agricultural synergist containing citronellal according to claim 6 in the preparation of insecticides, characterized in that: The agricultural synergist is compounded with an insecticide in a mass ratio of 1:(4-10); the insecticide is selected from at least one of chlorantraniliprole, deltamethrin and pymetrozine.

8. Use of the agricultural synergist containing citronellal according to claim 7 in the preparation of insecticides, characterized in that: The dosage form of the agricultural synergist is a pharmaceutically acceptable dosage form, including but not limited to emulsifiable concentrate, suspension, water-dispersible granules or soluble powder.

9. Use of the agricultural synergist containing citronellal according to claim 8 in the preparation of insecticides, characterized in that: The pest controlled by the insecticide is the two-spotted spider mite, whose Latin name is Tetranych usurticae.

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