Pesticide preparation with temperature response release function and application thereof

Abstract

The invention discloses a pesticide preparation with a temperature response release function and application thereof. The pesticide preparation comprises an active ingredient refined glufosinate-ammonium, an emulsifier, vegetable oil, an anti-freezing agent, a cross-linking agent and a gel component formed by reaction of an initiator. The pesticide preparation disclosed by the invention is suitable for preventing and controlling weeds in non-cultivated areas in fields, release of the active ingredient fine glufosinate-ammonium can be accurately controlled according to the change of environment temperature, and the optimal response temperature threshold value is 35-45 DEG C. When illumination is sufficient, the environment temperature reaches a threshold value, nanogel in the preparation swells rapidly, fine glufosinate-ammonium is promoted to be rapidly released at a proper rate, the period of relatively high activity and vigorous growth of glutamine synthetase of weeds in a high-temperature environment can be accurately matched, on-demand release of the fine glufosinate-ammonium salt is achieved, and the weeding effect is remarkably improved.

Description

Technical Field

[0001] This invention belongs to the field of pesticide formulation technology, specifically, it relates to a pesticide formulation with temperature-responsive release function and its application. Background Technology

[0002] In modern agricultural production, pesticides are a core element for controlling pests, diseases, and weeds, and ensuring high and stable crop yields. Their scientific and rational application is of great significance to the sustainable development of agriculture. However, traditional pesticide formulations have revealed many problems that urgently need to be solved in practical applications. For example, the release of pesticides is difficult to control precisely, and most pesticides are released rapidly after application, which not only wastes pesticides but also easily leads to pesticide residues in the environment, causing harm to the ecological environment and non-target organisms.

[0003] Glufosinate is a highly efficient, low-toxicity, non-selective herbicide. As an upgraded product of traditional glufosinate, it has become an important alternative to paraquat and glyphosate due to its optimized activity and environmentally friendly characteristics.

[0004] The efficacy of glufosinate-ammonium salts is highly dependent on light and favorable plant growth conditions. Its structure is similar to glutamate in plants, allowing it to competitively bind to the active site of glutamine synthase, disrupting glutamine synthesis, blocking nitrogen metabolism, and leading to intracellular ammonia accumulation. Ammonia accumulation damages chloroplast structure, thus hindering photosynthesis.

[0005] However, this process requires plants to be in an active photosynthetic state. Under sufficient light, plant photosynthesis is vigorous, with ample energy and carbon skeleton supply, and high glutamine synthetase activity, making glufosinate-ammonium salts more effective at inhibiting it. Under low light or cloudy / rainy conditions, plant metabolism slows down, making it difficult for pesticides to fully interfere with the photosynthetic system, resulting in delayed or weakened efficacy.

[0006] In recent years, temperature-responsive controlled-release technology, as a cutting-edge direction in the research and development of smart pesticide formulations, has shown great application potential in the field of precision application, providing innovative ideas and effective strategies for solving the problems existing in traditional pesticide formulations. Currently, there remains an unmet need for developing a nano-pesticide formulation that can precisely respond to changes in ambient temperature and achieve controlled release of glufosinate-ammonium salts. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a pesticide formulation with temperature-responsive release function, comprising the active ingredient glufosinate-ammonium salt, emulsifier, vegetable oil, antifreeze, and a gel component formed by the reaction of a crosslinking agent and an initiator, aiming to improve pesticide utilization, reduce environmental risks, and enhance weed control efficacy.

[0008] In one aspect, the present invention provides a pesticide formulation with temperature-responsive release function, wherein, by mass percentage, the pesticide formulation comprises 1-20% active ingredient, 1-6% nanogel, 1-20% emulsifier, 1-10% vegetable oil, 1-10% antifreeze, and the balance being a continuous phase;

[0009] The nanogel is obtained by reacting a crosslinking agent and an initiator in a suitable continuous phase, with a mass ratio of crosslinking agent to initiator of 2–50. The crosslinking agent is selected from one or more combinations of chitosan, comb-shaped oligoethylene glycol polymer, and poly(N-isopropylacrylamide). The initiator is selected from one or more combinations of sodium alginate, calcium chloride, sodium chloride, potassium alginate, ammonium persulfate, and sodium persulfate. The emulsifier is selected from one or more combinations of CS-PEG block copolymer, starch-PLA block copolymer, and PS-PEO block copolymer. The vegetable oil is selected from one or more combinations of castor oil, rosin-based vegetable oil, cashew nut shell oil, or grape seed oil. The antifreeze is selected from one or more combinations of ethylene glycol, propylene glycol, or glycerol.

[0010] In one or more embodiments, the active ingredient is glufosinate-ammonium salt.

[0011] In one or more embodiments, the continuous phase is deionized water.

[0012] In one or more embodiments, the crosslinking agent is a combination of chitosan, comb-shaped oligoethylene glycol polymer, and poly(N-isopropylacrylamide) in a mass ratio of (1.5–2.5):(1–2):(3–4).

[0013] In one or more embodiments, the initiator is a combination of sodium alginate, calcium chloride and ammonium persulfate, in a mass ratio of (2-3):(1-2):(0.5-1).

[0014] In one or more embodiments, the emulsifier is a combination of CS-PEG block copolymer, starch-PLA block copolymer and PS-PEO block copolymer, wherein the mass ratio of the three is (4.6-5.2):(1.2-3.3):(2.2-3.8).

[0015] In another aspect, the present invention provides the use of pesticide formulations as described in any embodiment herein in agriculture, wherein the pesticide formulations are used as herbicides.

[0016] In another aspect, the present invention provides a method for preparing a pesticide formulation as described in any embodiment herein, the method comprising the steps of preparing a nanogel solution, preparing an active ingredient emulsion, mixing the nanogel solution and the active ingredient emulsion, and high-pressure homogenization.

[0017] In one or more embodiments, the active ingredient is glufosinate-ammonium salt.

[0018] In one or more embodiments, the method includes the following steps:

[0019] S1: Dissolve the crosslinking agent in deionized water. After complete dissolution, add the initiator and react at 65-75°C for 3-5 hours, stirring the solution continuously during the reaction. After the reaction is complete, concentrate and filter the reaction product to obtain a nanogel solution.

[0020] S2: Glufosinate, vegetable oil, emulsifier, and antifreeze are dissolved in deionized water and subjected to high-speed shear homogenization to obtain glutfosinate emulsion.

[0021] S3: Mix the nanogel solution obtained in step S1 and the glufosinate-ammonium salt emulsion obtained in step S2, and perform high-pressure homogenization using a multi-channel microfluidic diamond interactive cavity device to obtain a temperature-responsive nanopesticide formulation of glufosinate-ammonium salt.

[0022] Preferably, in step S1, the reaction is carried out at 70°C for 4 hours.

[0023] Preferably, in step S1, the stirring rate is 300 r / min.

[0024] Preferably, in step S1, the molecular weight cutoff for the concentration filtration is 3500 Da.

[0025] Preferably, in step S2, the rotation speed during the high-speed shearing homogenization process is 5000 r / min.

[0026] Preferably, in step S3, the working pressure of the high-pressure homogenization process is 22000-27000 psi, and the homogenization flow rate is 90-110 mL / min.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1. The pesticide formulation of this invention is suitable for the control of weeds in non-cultivated fields. It can precisely control the release of the active ingredient, glufosinate-ammonium salt, according to changes in ambient temperature, with an optimal response temperature threshold between 35℃ and 45℃. When the ambient temperature reaches the threshold under sufficient sunlight, the nanogel in the formulation rapidly swells, promoting the rapid release of glufosinate-ammonium salt at an appropriate rate. This precisely matches the period when weeds have high glutamine synthase activity and vigorous growth under high-temperature conditions, achieving on-demand release of glufosinate-ammonium salt and significantly improving the weeding effect.

[0029] 2. The nanogel component in the pesticide formulation of the present invention can effectively reduce the contact between the active ingredient glufosinate and external factors (such as light and moisture), reduce the degradation rate of glufosinate, thereby improving the stability of glufosinate and extending the shelf life of glufosinate.

[0030] 3. The pesticide formulation of the present invention can achieve precise release of glufosinate-ammonium salt, and can significantly reduce the amount of pesticide used while achieving the same weeding effect, reduce the residue of glufosinate-ammonium salt in soil and water, and reduce the harm to the ecological environment and non-target organisms.

[0031] 4. The pesticide formulation of this invention adopts a multiple emulsion system, which has excellent stability and dispersibility. Furthermore, the viscosity of the formulation can be adjusted by adjuvants, making it more convenient and uniform to apply during actual spraying and other processes, thus improving the spraying experience. Attached Figure Description

[0032] Figure 1 This refers to the release rate of glufosinate-ammonium salt in each formulation at 25℃.

[0033] Figure 2 This refers to the release rate of glufosinate-ammonium salt in each formulation at 35℃.

[0034] Figure 3 This refers to the release rate of glufosinate-ammonium salt in each formulation at 45℃.

[0035] Figure 4 This refers to the release rate of glufosinate-ammonium salt in each formulation at 55℃.

[0036] Figure 5 This refers to the release rate of glufosinate-ammonium salt in each formulation at 65℃. Detailed Implementation

[0037] In this invention, the preparation method of the temperature-responsive nano-pesticide formulation of glufosinate-ammonium salt is as follows: A crosslinking agent is dissolved in an appropriate amount of deionized water according to a certain ratio. After complete dissolution, an initiator is added, and the reaction is carried out at 60–80°C and a stirring rate of 250–350 r / min for 3–5 hours. The reaction product is filtered and concentrated to obtain a nano-gel solution. Then, glufosinate-ammonium salt, vegetable oil, emulsifier, and antifreeze are dissolved in deionized water according to a certain ratio and homogenized by high-speed shearing at a speed of 4500–5500 r / min to obtain a glufosinate-ammonium salt emulsion. Finally, the nano-gel solution and the glufosinate-ammonium salt emulsion are mixed and homogenized under high pressure using a multi-channel microfluidic diamond interactive cavity device (homogenization pressure of 22000–27000 psi, homogenization flow rate of 90–110 mL / min) to obtain the temperature-responsive nano-pesticide formulation of glufosinate-ammonium salt.

[0038] The crosslinking agent is selected from one or more combinations of chitosan, comb-shaped oligoethylene glycol polymer, and poly(N-isopropylacrylamide); the initiator is selected from one or more combinations of sodium alginate, calcium chloride, sodium chloride, potassium alginate, ammonium persulfate, and sodium persulfate; the emulsifier is selected from one or more combinations of CS-PEG block copolymer, starch-PLA block copolymer, and PS-PEO block copolymer; the vegetable oil is selected from one or more combinations of castor oil, rosin-based vegetable oil, cashew nut shell oil, or grape seed oil; and the antifreeze is selected from one or more combinations of ethylene glycol, propylene glycol, or glycerol.

[0039] During the reaction, cross-linking may occur between the initiators, but not enough to form a nanogel.

[0040] During the reaction, the chitosan in the crosslinking agent can chelate calcium ions of calcium chloride in the initiator.

[0041] Example 1:

[0042] This embodiment presents a temperature-responsive controlled-release nanopesticide formulation, using glufosinate as the active ingredient, combined with a crosslinking agent, initiator, emulsifier, vegetable oil, antifreeze, and deionized water to form a glufosinate temperature-responsive nanopesticide formulation. The formulation of the glufosinate temperature-responsive nanopesticide formulation is shown in Table 1 below.

[0043] Table 1: Temperature-responsive Nanopesticide Formulations of Glufosinate-ammonium Salts

[0044]

[0045]

[0046] The crosslinking agent was dissolved in an appropriate amount of deionized water according to a certain ratio. After complete dissolution, the initiator was added, and the reaction was carried out at 70℃ and a stirring rate of 300 r / min for 4 hours. The reaction product was filtered and concentrated to obtain a nanogel solution with a molecular weight cutoff of 3500 Da. Then, glufosinate, vegetable oil, emulsifier, and antifreeze were dissolved in deionized water according to a certain ratio and homogenized by high-speed shearing at a speed of 5000 r / min to obtain glufosinate emulsion. Finally, the nanogel solution and glufosinate emulsion were mixed and homogenized under high pressure using a multi-channel microfluidic diamond interactive cavity device (homogenization pressure of 22000-27000 psi and homogenization flow rate of 90-110 mL / min) to obtain a temperature-responsive nanopesticide formulation of glufosinate.

[0047] Example 2:

[0048] This embodiment presents a temperature-responsive controlled-release nanopesticide formulation, using glufosinate as the active ingredient, combined with a crosslinking agent, initiator, emulsifier, vegetable oil, antifreeze, and deionized water to form a glufosinate temperature-responsive nanopesticide formulation. The formulation of the glufosinate temperature-responsive nanopesticide formulation is shown in Table 2 below.

[0049] Table 2: Temperature-responsive Nanopesticide Formulations of Glufosinate-ammonium Salts

[0050]

[0051] The crosslinking agent was dissolved in an appropriate amount of deionized water according to a certain ratio. After complete dissolution, the initiator was added, and the reaction was carried out at 70℃ and a stirring rate of 300 r / min for 4 hours. The reaction product was filtered and concentrated to obtain a nanogel solution with a molecular weight cutoff of 3500 Da. Then, glufosinate, vegetable oil, emulsifier, and antifreeze were dissolved in deionized water according to a certain ratio and homogenized by high-speed shearing at a speed of 5000 r / min to obtain glufosinate emulsion. Finally, the nanogel solution and glufosinate emulsion were mixed and homogenized under high pressure using a multi-channel microfluidic diamond interactive cavity device (homogenization pressure of 22000-27000 psi and homogenization flow rate of 90-110 mL / min) to obtain a temperature-responsive nanopesticide formulation of glufosinate.

[0052] Example 3:

[0053] This embodiment presents a temperature-responsive controlled-release nanopesticide formulation, using glufosinate as the active ingredient, combined with a crosslinking agent, initiator, emulsifier, vegetable oil, antifreeze, and deionized water to form a glufosinate temperature-responsive nanopesticide formulation. The formulation of the glufosinate temperature-responsive nanopesticide formulation is shown in Table 3 below.

[0054] Table 3: Temperature-responsive Nanopesticide Formulations of Glufosinate-ammonium Salts

[0055]

[0056] The crosslinking agent was dissolved in an appropriate amount of deionized water according to a certain ratio. After complete dissolution, the initiator was added, and the reaction was carried out at 70℃ and a stirring rate of 300 r / min for 4 hours. The reaction product was filtered and concentrated to obtain a nanogel solution with a molecular weight cutoff of 3500 Da. Then, glufosinate, vegetable oil, emulsifier, and antifreeze were dissolved in deionized water according to a certain ratio and homogenized by high-speed shearing at a speed of 5000 r / min to obtain glufosinate emulsion. Finally, the nanogel solution and glufosinate emulsion were mixed and homogenized under high pressure using a multi-channel microfluidic diamond interactive cavity device (homogenization pressure of 22000-27000 psi and homogenization flow rate of 90-110 mL / min) to obtain a temperature-responsive nanopesticide formulation of glufosinate.

[0057] Example 4:

[0058] This embodiment presents a temperature-responsive controlled-release nanopesticide formulation, using glufosinate as the active ingredient, combined with a crosslinking agent, initiator, emulsifier, vegetable oil, antifreeze, and deionized water to form a glufosinate temperature-responsive nanopesticide formulation. The formulation of the glufosinate temperature-responsive nanopesticide formulation is shown in Table 4 below.

[0059] Table 4: Temperature-responsive Nanopesticide Formulations of Glufosinate-ammonium Salts

[0060]

[0061]

[0062] The crosslinking agent was dissolved in an appropriate amount of deionized water according to a certain ratio. After complete dissolution, the initiator was added, and the reaction was carried out at 70℃ and a stirring rate of 300 r / min for 4 hours. The reaction product was filtered and concentrated to obtain a nanogel solution with a molecular weight cutoff of 3500 Da. Then, glufosinate, vegetable oil, emulsifier, and antifreeze were dissolved in deionized water according to a certain ratio and homogenized by high-speed shearing at a speed of 5000 r / min to obtain glufosinate emulsion. Finally, the nanogel solution and glufosinate emulsion were mixed and homogenized under high pressure using a multi-channel microfluidic diamond interactive cavity device (homogenization pressure of 22000-27000 psi and homogenization flow rate of 90-110 mL / min) to obtain a temperature-responsive nanopesticide formulation of glufosinate.

[0063] Comparative Example 1:

[0064] This comparative example prepared pesticide formulations according to the components and methods of Example 2, except for the ratio of emulsifiers, namely the ratio of CS-PEG block copolymer, starch-PLA block copolymer and PS-PEO block copolymer is 3:1:4, and its formulation is shown in Table 5 below.

[0065] Table 5: Temperature-responsive Nanopesticide Formulations of Glufosinate-ammonium Salts

[0066]

[0067] Comparative Example 2:

[0068] This comparative example prepared pesticide formulations according to the components and methods of Example 2, except for the ratio of crosslinking agents, namely chitosan, comb-shaped oligoethylene glycol polymer and poly-N-isopropylacrylamide, which was 3.3:0.8:4.3, and its formulation is shown in Table 6 below.

[0069] Table 6: Temperature-responsive Nanopesticide Formulations of Glufosinate-ammonium Salts

[0070]

[0071] Comparative Example 3:

[0072] This comparative example prepared pesticide formulations according to the components and methods of Example 2, except for the ratio of the initiator, namely sodium alginate, calcium chloride and ammonium persulfate, which is 1.2:2.5:0.3, and its formulation is shown in Table 7 below.

[0073] Table 7: Temperature-responsive Nanopesticide Formulations of Glufosinate-ammonium Salt

[0074]

[0075] Comparative Example 4:

[0076] This comparative example prepared pesticide formulations according to the components and methods of Example 2, except that conventional emulsifiers were used, and no crosslinking agents, initiators, or vegetable oils were added. It also adopted a conventional pesticide soluble formulation preparation process, and its formulation is shown in Table 8 below.

[0077] Table 8: Temperature-responsive Nanopesticide Formulations of Glufosinate-ammonium Salt

[0078]

[0079]

[0080] Comparative Example 5:

[0081] This comparative example prepared pesticide formulations according to the components and methods of Example 2, except that the crosslinking agent did not contain comb-shaped oligoethylene glycol polymers, i.e., the ratio of chitosan to poly(N-isopropylacrylamide) was 2.1:3.8, and its formulation is shown in Table 9 below.

[0082] Table 9: Temperature-responsive Nanopesticide Formulations of Glufosinate-ammonium Salts

[0083]

[0084] Comparative Example 6:

[0085] This comparative example prepared pesticide formulations according to the components and methods of Example 2, except that sodium alginate was not used in the initiator, i.e. the ratio of calcium chloride to ammonium persulfate was 1.2:0.5, and its formulation is shown in Table 10 below.

[0086] Table 10: Temperature-responsive Nanopesticide Formulations of Glufosinate-ammonium Salts

[0087]

[0088] Comparative Example 7:

[0089] This comparative example prepared pesticide formulations according to the components and methods of Example 2, except that the initiator did not contain calcium chloride, i.e., the ratio of sodium alginate to ammonium persulfate was 2.8:0.5, and its formulation is shown in Table 11 below.

[0090] Table 11: Temperature-responsive Nanopesticide Formulations of Glufosinate-ammonium Salts

[0091]

[0092] Experimental Example 1: Particle Size Distribution Test

[0093] The particle size distribution of pesticide formulations prepared in Examples 1-4 and Comparative Examples 1-7 at room temperature and under heat storage (stored at 54°C for 14 days) was analyzed using a BeNano 90Zeta nanoparticle size and Zeta potential analyzer. The results are shown in Table 12 below. A smaller average particle size indicates a more stable formulation; a smaller polydispersity index indicates a more uniform particle size distribution.

[0094] Table 12: Particle size distribution test results

[0095]

[0096]

[0097] The comparison results in the table above show that the pesticide formulations of formulations 1 to 4 have smaller particle sizes (Z-average particle size ≤ 200 nm) and lower polydispersity index (PDI ≤ 0.3), indicating more uniform particle size distribution and good stability. The formulation sample of Example 1 has the smallest particle size and the best stability. In contrast, formulations 5 to 11 have significantly larger particle sizes, significantly higher polydispersity indexes, and poorer stability. Note that Comparative Example 4, being a conventional pesticide soluble concentrate, formed a true solution, making it impossible to determine its particle size.

[0098] Experimental Example 2: Release rate under different temperature conditions

[0099] This experimental example simulates the natural release at response and non-response temperatures to determine the release amount of glufosinate-ammonium salt in the pesticide formulation samples prepared in Example 2 and Comparative Examples 1 to 4, thereby determining their temperature-responsive release characteristics.

[0100] The above pesticide formulation samples were diluted with deionized water to a glufosinate-ammonium salt concentration of 10 mg / L, placed in conical flasks, and sealed to serve as test samples (three parallel tests were set up for each group of samples). The flasks were then placed in a constant-temperature water bath shaker and shaken at a constant temperature. The temperature gradients were set at 25℃, 35℃, 45℃, 55℃, and 65℃, and the shaking frequency was 100 rpm. Pre-equilibration was performed for 30 minutes.

[0101] During the temperature-responsive release process monitoring phase, samples were taken at 0.5h, 1h, 2h, 4h, 8h, 12h, and 24h, and rapidly cooled in an ice bath for 10 minutes to terminate the release process. Subsequently, high-performance liquid chromatography (HPLC) was used to detect changes in the concentration of glufosinate-ammonium in each test sample. The monitoring results are as follows: Figures 1-5 The figures show the release rates during water baths at 25℃, 35℃, 45℃, 55℃, and 65℃, respectively. The release rate is calculated based on the concentration of glufosinate-ammonium salt at different time points using the following formula:

[0102]

[0103] Where Tx represents a sampling time point, and T0 represents the initial time point when the water bath begins.

[0104] like Figures 1-5As shown, at 25°C, the glufosinate-ammonium salt in the formulation of Example 2 was almost not released, while the formulations of Comparative Examples 1-4 all had release rates higher than 20% after 24 hours, with the formulation of Comparative Example 3 reaching nearly 60%. At 35°C, the release rate of glufosinate-ammonium salt in the formulation of Example 2 was about 60% after 24 hours, while the release rates of the formulations of Comparative Examples 1-4 were all above 60% after 24 hours, with the formulation of Comparative Example 3 reaching nearly 90%. At 45°C, the release of glufosinate-ammonium salt in the formulation of Example 2 maintained an approximately linear release between 4 hours and 24 hours, with a release rate of about 60% at 4 hours and reaching over 90% by 24 hours. The release rates of the formulations in Example 2 were as follows: The formulations in Comparative Examples 1-4 all showed release rates of over 80% at 4 hours, with Comparative Example 3 reaching nearly 100% release at 8 hours. At 55°C, the glufosinate-ammonium salt in Example 2 maintained an approximately linear release between 2 and 12 hours, with a release rate exceeding 90% at 12 hours. The formulations in Comparative Examples 1-4 showed a release rate of nearly 100% at 4 hours, with Comparative Example 3 reaching nearly 100% release at 4 hours. At 65°C, the formulation in Example 2 reached nearly 100% release at 4 hours, while the formulations in Comparative Examples 1-4 reached nearly 100% release at 2 hours.

[0105] Overall, at 25°C, 35°C, 45°C and 55°C, the release rate of glufosinate-ammonium salt in the formulation of Example 2 was slower than that in the formulations of Comparative Examples 1 to 4, and the release rate had a better linear relationship with time. This is beneficial for solving the problem of most existing pesticides releasing too quickly after application, as well as the resulting pesticide waste and environmental residues.

[0106] Experiment Example 3: Herbal Efficacy Test of Non-Cultivated Land

[0107] This experiment was conducted in Sanxing Village, Xiannv Town, Jiangdu District, Yangzhou City, Jiangsu Province. The main weeds in the experimental plot were goosegrass and crabgrass, with an average of 37.2 goosegrass plants / m². 2 It accounted for 42.27% of the total grass count, with crabgrass at 25.5 plants / m². 2 It accounted for 28.8% of the total number of grasses, with Amaranth at 7.8 plants / m². 2 It accounted for 8.86% of the total weeds. Other weeds included barnyard grass, wrinkled amaranth, and sedge, which were counted as broadleaf weeds and grass weeds, respectively.

[0108] The dosage of active ingredients in formulas 1-11 is 300 grams per hectare, with a dilution rate of 450 L of water per hectare. Each experimental plot is 30 m². 2Repeat 3 times. During the vigorous growth period of weeds, apply the herbicide evenly to the entire plant using a manual sprayer. The treatment group was sprayed with any of formulations 1-8; a control group was sprayed with water instead of the formulation. Weed counts were collected in each plot at 15 and 30 days after application, and the fresh weight of the weeds was measured at the final count. The herbicidal effect was investigated, and the weed control effect was calculated using the following formula:

[0109]

[0110] The statistical difference analysis of the control efficacy was performed using Duncans' new multiple range method, and the results are shown in Table 13. The significance of the control efficacy among the groups is indicated by English letters.

[0111] Table 13: Results of Field Efficacy Trials

[0112]

[0113]

[0114] As shown in Table 13, statistical analysis using Duncans' new multiple range method revealed that the temperature-responsive nano-pesticide formulations of glufosinate-ammonium salt in Examples 1-4 exhibited significantly higher control efficacy than those in Comparative Examples 1-7, with control efficacy remaining at 95% after 30 days post-application. Furthermore, they possessed both rapid and sustained-release effects. Field efficacy trials fully demonstrate that their temperature-responsive mechanism enables the active ingredients to precisely target enzymes in weeds, significantly enhancing weed control efficacy from a mechanism-of-action perspective. This demonstrates their significant application value in agriculture and promises to provide a more effective solution for weed control in agricultural production.

Claims

1. A pesticide formulation with temperature-responsive release function, characterized in that, The pesticide formulation comprises, by mass percentage, 1-20% active ingredient, 1-6% nanogel, 1-20% emulsifier, 1-10% vegetable oil, 1-10% antifreeze, and the balance being a continuous phase; The nanogel is obtained by reacting a crosslinking agent and an initiator in a suitable continuous phase, with a mass ratio of crosslinking agent to initiator of 2–50. The crosslinking agent is selected from one or more combinations of chitosan, comb-shaped oligoethylene glycol polymer, and poly(N-isopropylacrylamide). The initiator is selected from one or more combinations of sodium alginate, calcium chloride, sodium chloride, potassium alginate, ammonium persulfate, and sodium persulfate. The emulsifier is selected from one or more combinations of CS-PEG block copolymer, starch-PLA block copolymer, and PS-PEO block copolymer. The vegetable oil is selected from one or more combinations of castor oil, rosin-based vegetable oil, cashew nut shell oil, or grape seed oil. The antifreeze is selected from one or more combinations of ethylene glycol, propylene glycol, or glycerol.

2. The pesticide formulation as described in claim 1, characterized in that, The active ingredient is glufosinate-ammonium salt.

3. The pesticide formulation as described in claim 1, characterized in that, The continuous phase is deionized water.

4. The pesticide formulation as described in claim 1, characterized in that, The crosslinking agent is a combination of chitosan, comb-shaped oligoethylene glycol polymer, and poly(N-isopropylacrylamide) in a mass ratio of (1.5–2.5):(1–2):(3–4).

5. The pesticide formulation as described in claim 1, characterized in that, The initiator is a combination of sodium alginate, calcium chloride and ammonium persulfate, with a mass ratio of (2-3):(1-2):(0.5-1).

6. The pesticide formulation according to claim 1, characterized in that, The emulsifier is a combination of CS-PEG block copolymer, starch-PLA block copolymer and PS-PEO block copolymer, with a mass ratio of (4.6-5.2):(1.2-3.3):(2.2-3.8).

7. The application of the pesticide formulation as described in any one of claims 1 to 6 in agriculture, characterized in that, The pesticide formulation is used as a herbicide.

8. A method for preparing a pesticide formulation as described in any one of claims 1 to 6, characterized in that, The method includes the steps of preparing a nanogel solution, preparing an active ingredient emulsion, mixing the nanogel solution and the active ingredient emulsion, and high-pressure homogenization.

9. The method as described in claim 8, characterized in that, The active ingredient is glufosinate-ammonium salt.

10. The method as described in claim 9, characterized in that, The method includes the following steps: S1: Dissolve the crosslinking agent in deionized water. After complete dissolution, add the initiator and react at 65-75°C for 3-5 hours, stirring the solution continuously during the reaction. After the reaction is complete, concentrate and filter the reaction product to obtain a nanogel solution. S2: Glufosinate, vegetable oil, emulsifier, and antifreeze are dissolved in deionized water and subjected to high-speed shear homogenization to obtain glutfosinate emulsion. S3: Mix the nanogel solution obtained in step S1 and the glufosinate-ammonium salt emulsion obtained in step S2, and perform high-pressure homogenization using a multi-channel microfluidic diamond interactive cavity device to obtain a temperature-responsive nanopesticide formulation of glufosinate-ammonium salt.

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