Synergistic metconazole as well as preparation method and application thereof

Abstract

The invention provides synergistic metconazole as well as a preparation method and application thereof, and belongs to the technical field of chemical pesticides. The metconazole dispersible oil suspending agent is prepared by mixing a metconazole active compound, an emulsifier, a thickening agent and a solvent, and sequentially shearing and sanding the mixture. The adhesiveness and the anti-scouring capability of liquid drops of liquid medicine can be greatly improved, the lasting period of the liquid drops is prolonged, and the prevention and treatment effect of metconazole can be exerted to a certain extent; meanwhile, the permeability can be improved, so that more effective components enter crops to reduce various loss conditions, and good stability is achieved; the physical and chemical properties of the metconazole dispersible oil suspending agent are determined by a CIPAC method, all indexes meet the requirements of pesticide preparations, the metconazole dispersible oil suspending agent can be used for unmanned aerial vehicle pesticide application, the defects that a water-based dosage form is prone to evaporation and drifting when an unmanned aerial vehicle is used for pesticide application are overcome, unmanned aerial vehicle pesticide application is more efficient and convenient, and the metconazole dispersible oil suspending agent has good application prospects in some areas limited by terrains and landforms. And the method has good applicability. The composition can be used for preventing and treating wheat scab, and the prevention effect can reach 86.89%; and diseases are reduced, the income of planters is increased, and the method is suitable for popularization and application.

Description

Technical Field

[0001] The invention relates to the technical field of chemical pesticides, and in particular to a synergistic metconazole and a preparation method and application thereof. Background Art

[0002] Pesticides play an extremely important role in fighting harmful organisms and ensuring the safety of crop production, and are important means of production. As a global food crop, wheat has many diseases and pests in its production, which harm the yield and quality of wheat. Common diseases and pests include sheath blight, powdery mildew, rust, fusarium head blight, aphids, wheat spiders, etc. Among them, fusarium head blight is a disease that has a greater impact on wheat production. The control effect of this disease will directly affect the yield and quality of wheat grains. At this stage, the control of fusarium head blight is still mainly based on chemical control.

[0003] Chemical pesticides have problems such as high cost and long development cycle. It is very difficult to synthesize commercially available and innovative pesticide compounds, and developing them into suitable dosage forms can help their long-term development. Therefore, in recent years, the research and development of pesticide dosage forms, especially the development of green, efficient and labor-saving new dosage forms, has received widespread attention from various industries. The choice of dosage form is not only determined by the physical and chemical properties of the original drug, but also its safety, stability and convenience must be considered comprehensively. Traditional dosage forms such as emulsifiable concentrates and wettable powders use a large amount of organic solvents or are prone to dust pollution, pesticide damage, short effective period and environmental impact. Therefore, it is necessary to develop environmentally friendly water-based and labor-saving dosage forms such as suspensions, water-dispersible granules, dispersible oil suspensions and other dosage forms. Among them, the registration proportion of dispersible oil suspensions is increasing, and the future market potential and research value are considerable.

[0004] As a new type of triazole fungicide, metconazole has a broad spectrum of systemicity, good protective and therapeutic effects, low toxicity to non-target organisms, low dosage, and meets the requirements of green prevention and control. Its market prospects are very broad. Therefore, in order to improve its target deposition efficiency and reduce drug loss, it is necessary to develop an efficient formulation. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a synergistic metconazole and a preparation method and application thereof. Based on the physicochemical properties of metconazole preparations, a highly effective control agent for wheat fusarium wilt, and the low-volume spraying method of plant protection drones, the present invention uses methyl oleate as a dispersion medium, has the best performance, low cost, no dust pollution, safety and environmental protection; improves the utilization rate of pesticides and reduces the loss of droplets during the spraying process.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] In a first aspect, the present invention provides a synergistic metconazole, which is obtained by preparing a metconazole dispersible oil suspension concentrate using metconazole technical.

[0008] In a second aspect, the present invention provides a method for preparing a metconazole dispersible oil suspension, comprising the following steps:

[0009] The metconazole technical, emulsifier, thickener and solvent are mixed and then sheared and sand-milled in sequence to obtain the metconazole dispersible oil suspension.

[0010] Preferably, the mass ratio of metconazole technical, emulsifier, thickener and solvent is 8:8-15:1-3:74-81.

[0011] Preferably, the emulsifier is one or more of N600, EF68, and EF69.

[0012] More preferably, the emulsifier is N600.

[0013] Preferably, the thickener is one or more of organic bentonite, white carbon black, and modified hydrogenated castor oil.

[0014] Preferably, the solvent is methyl oleate or S-150 mineral oil.

[0015] More preferably, the solvent is methyl oleate.

[0016] Preferably, the sanding parameters are:

[0017] The grinding rate is 1800r / min;

[0018] The grinding time was 60 min.

[0019] Preferably, the particle size D of the metconazole dispersible oil suspension is 50 ≤5μm.

[0020] In a third aspect, the present invention provides the use of the above-mentioned metconazole dispersible oil suspension in drone pesticide application.

[0021] Beneficial technical effects:

[0022] The invention develops metconazole into a dispersible oil suspension, which can greatly improve the adhesion and anti-scouring ability of the drug liquid droplets, enhance its lasting effect, and to a certain extent, will be beneficial to the control effect of metconazole; at the same time, its permeability can be improved, so that more effective ingredients can enter the crops and reduce various losses; the agent is stable in cold storage (0±2°C) and hot storage (54±2°C) tests, and the decomposition rate of the effective ingredients is less than 5%. In addition, after 6 months of storage, the drug liquid does not have the phenomenon of creaming, bottoming, etc., indicating that the emulsion has good stability; the physical and chemical properties of the metconazole dispersible oil suspension are determined by the CIPAC method, and all indicators meet the requirements of pesticide preparations.

[0023] After developing metconazole into a dispersible oil suspension, it can be used for drone application, overcoming the shortcomings of water-based formulations that are easy to evaporate and drift when used with drones, making drone application more efficient and convenient, and has good applicability to some areas restricted by terrain and landforms.

[0024] The metconazole dispersible oil suspension of the invention can be used for preventing and controlling wheat scab, and the prevention efficiency can reach 86.89%; the occurrence of the disease is reduced, the income of growers is increased, and the invention is suitable for popularization and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A flow chart of the preparation process;

[0026] Figure 2 The distribution of the particle size of the drug solution, where (a) methyl oleate is used as the solvent; (b) S-150 is used as the solvent;

[0027] Figure 3 This is a graph showing the change in surface tension of different pesticide solutions with dilution multiples;

[0028] Figure 4 The contact angle diagram of pesticide solutions with different concentrations on wheat leaves;

[0029] Figure 5 This is an image showing the change of pesticide droplet morphology over time in the OD system with methyl oleate as solvent;

[0030] Figure 6 This is the image of the change of pesticide droplet morphology over time in the OD system with S-150 as solvent;

[0031] Figure 7 This is an image of the change in the morphology of pesticide droplets in the SC system over time. DETAILED DESCRIPTION

[0032] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0033] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0034] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0035] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present application description and examples are exemplary only.

[0036] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0037] The "room temperature" and "normal temperature" mentioned in the present invention are all calculated as 25±2°C unless otherwise specified.

[0038] Unless otherwise specified, the equipment or raw materials used in the following examples can be commercially available.

[0039] Example 1

[0040] 1.1 Materials and Instruments

[0041] 1.1.1 Test materials

[0042] 98% metconazole technical (Zhejiang Yulong Biotechnology Co., Ltd.); N600 (Daqian High-tech Research Center Co., Ltd.); EF68 (Beijing Greentime Technology Co., Ltd.); EF69 (Beijing Greentime Technology Co., Ltd.) methyl oleate (Suzhou Fengbei Biotechnology Co., Ltd.); S-150 mineral oil (Jiangsu Hualun Chemical Co., Ltd.); organic bentonite (Shandong Kesaijinong Holdings Co., Ltd.).

[0043] 1.1.2 Test equipment

[0044] Sand mill RTSM-0.2BJ (Shanghai Rutech Electromechanical Equipment Co., Ltd.); electronic balance with an accuracy of 0.0001g (Tianjin Huifeng Green Instrument Co., Ltd.); DCAT25 surface tension meter (Germany Dataphysics Company); OCA25 video optical contact angle meter (Germany Dataphysics Company); blast drying oven (Shanghai Yiheng Scientific Instrument Co., Ltd.); laser particle size distribution analyzer (Dandong Better Instrument Co., Ltd.).

[0045] 1.2 Test methods

[0046] 1.2.1 Sample preparation

[0047] Methods:

[0048] According to the following formula, (calculated as 250g) metconazole technical 20g (8%), emulsifier 20g (8%), organic soil 5g (2%), solvent oil to 250g, cut evenly according to the proportion, pour into the sand mill, then add a certain proportion of zirconium beads (0.8 ~ 1.0μm), grind at a speed of 1800r / min for 60min, and sand grind to a particle size D 50 ≤5μm, bottled for later use. Figure 1 shown.

[0049] 1.2.2 Emulsifier and thickener screening

[0050] According to the formula in Table 1, a dispersible oil suspension is prepared, and 8%-15% of emulsifier and 1%-3% of thickener are mixed with the original drug, and then solvent oil is used to make up to 250g. After preparation, the drug solution is subjected to stability test.

[0051] Table 1 Preparation of Metconazole Dispersible Oil Suspension Concentrate

[0052]

[0053] 1.3 Stability determination

[0054] 1.3.1 Determination of thermal storage stability

[0055] For the hot storage stability test method, refer to GB / T 19136-2021. Add 20g of sample into a transparent sample bottle and place it in a constant temperature blast drying oven at (54±2)℃. After 14 days, observe the changes in the appearance of the sample and determine its active ingredient content within 24 hours. Evaluation criteria: the appearance of the sample is homogeneous and stable, with no precipitation, no oil separation (or recovery after gentle shaking), etc. At the same time, the decomposition rate of the active ingredient is ≤5%, which is qualified. Each sample is repeated 6 times. The test results are shown in Table 2-3.

[0056] Table 2 Effect of different amounts of emulsifier on thermal storage stability of preparations (methyl oleate as solvent)

[0057]

[0058]

[0059] Table 3 Effect of different amounts of emulsifier on thermal storage stability of preparations (with S-150 as solvent)

[0060]

[0061]

[0062] 1.3.2 Low temperature stability determination

[0063] For the low temperature stability test method, refer to GB / T 19137-2003. Take the sample and add it to the sample bottle, seal it and place it at (0±2)℃ for 7 days, observe the appearance of the sample for oil separation, precipitation and other phenomena, if there is no change, it is regarded as a qualified sample, and each sample is repeated 6 times, see Table 4.

[0064] 1.4 Formulation Optimization

[0065] In order to optimize the liquid formulation, orthogonal experiments were conducted on formulations containing different surfactants (emulsifiers N600, EFR68 and EF69) at different concentrations (15%-6%). The stability of the liquid was preliminarily evaluated by monitoring the appearance changes from 0h to 14d. The orthogonal test results are shown in Tables 4-6.

[0066] Table 4 Effect of different dosages of thickener on formulation stability

[0067]

[0068] Table 5 Screening of emulsifiers (methyl oleate as solvent)

[0069]

[0070]

[0071] Table 6 Screening of emulsifiers (using S-150 as solvent)

[0072]

[0073]

[0074] The results in Tables 3 and 4 show that in the two selected solvents, the suspension using emulsifier N600 was relatively stable and uniform within 14 days, and the appearance of the solution did not change significantly, indicating long-term physical stability. The effect of emulsifier EF68 in the two solvents was weaker than that of emulsifier N600.

[0075] 2 Performance measurement

[0076] 2.1 Performance Characterization

[0077] The physical and chemical indicators of the most stable solution were tested by the CIPAC method. The formula of 8% metconazole dispersible oil suspension was obtained by adding the active ingredient of metconazole and 8% N600 to methyl oleate or S-150 solvent and grinding them into a homogeneous phase, and its storage stability, pourability test, persistent foaming, pH and other indicators were tested (the average values ​​of the two were recorded in Table 7).

[0078] Table 7 Quality standard test results of stable drug solution

[0079]

[0080]

[0081] The data analysis in Table 5 shows that at 0°C, the suspension did not precipitate or emulsify. After 14 days of hot storage at 54±2°C, a small amount of stratification appeared in the bottle, but the liquid became uniform after shaking, indicating that the stability of the liquid system was qualified. The test results of other indicators met the requirements of pesticide formulations.

[0082] 2.2 Particle size determination

[0083] The particle size of each sample was tested using a laser particle size analyzer. The test was repeated 5 times and D was calculated. 50 Average value, see Figure 2 .

[0084] 2.3 Determination of wettability

[0085] 2.3.1 Static surface tension (SST)

[0086] 8% metconazole dispersible oil suspension was diluted with deionized water to 10, 100, 500, 1000 times of aqueous solution; the static surface tension of the dilution was measured using a DCAT25 surface interfacial tension meter (Germany Dataphysics Company), and each sample was measured 3 times and the average value was taken. The test temperature was 20±1℃, and the test results were shown in Figure 3 .

[0087] like Figure 3As shown, the surface tension of the two solvent oils prepared by the dilution of 10 times, 100 times, 500 times, and 1000 times gradually increased with the increase of the dilution times. Compared with the other two liquid medicines, the suspension system (8% metconazole OD) prepared with methyl oleate as solvent oil had the lowest surface tension value. When the solution was not diluted (control), the value was about 25.37mN / m.

[0088] 2.3.2 Dynamic contact angle (DCA)

[0089] 8% metconazole dispersible oil suspension was diluted with deionized water to 10, 100, 500, 1000 times of aqueous solution; a drop of liquid was dropped on a wheat leaf with a needle with an inner diameter of φ = 0.8 mm, and the contact angle was measured once every 1 second using an OCA25 video optical contact angle measuring instrument (Dataphysics, Germany), for 0 to 6 minutes, repeated 3 to 4 times, and the drop shape at 0, 1, 2, 3, 4, 5, and 6 minutes was photographed. The test temperature was 20 ± 1 ° C, and the test results were shown in Figure 4 .

[0090] Depend on Figure 4 It can be seen that for pesticide solutions with different dispersion media, the initial contact angle value decreases with the increase of concentration. At the same dilution multiple, the initial contact angle of the OD suspension is smaller than that of the SC suspension. At the same dosage form and concentration, the initial contact angle of the suspension prepared with methyl oleate solvent oil is smaller than the initial contact angle of the suspension prepared with S-150. Among them, the contact angle value of the solution diluted 10 times is the lowest, indicating that the wettability on the wheat leaf surface is excellent. The contact angle of the solution diluted 10 times and 100 times gradually decreases over time within 30s. For solutions diluted 500 times and 1000 times, the contact angle remains almost constant, and the initial value is about 100°, which indicates that the wettability on the wheat leaves is poor. Among them, for the suspension prepared with methyl oleate as solvent oil, the difference in contact angle values ​​between different diluted solutions is more obvious.

[0091] 3 Bounce test

[0092] Figures 5 to 7The images are of the change of droplet morphology over time after the droplets of 10-fold, 100-fold, 500-fold, and 1000-fold diluted suspension hit wheat leaves. It is known that wheat leaves are hydrophobic interfaces. In the OD and SC systems, the undiluted droplets in the control group, in the SC system, after the droplets experienced spreading and retraction, droplet separation and rolling occurred at the edge of the droplets as time increased. The droplets of the liquid prepared with methyl oleate and S-150 as solvent oil experienced spreading, retraction, and leaf surface rebound after hitting the wheat leaves. The droplets spread to the maximum in 1.5ms to 2.0ms, and then retracted. There were almost no droplets separated from the edge of the droplets. Among them, the liquid prepared with methyl oleate as the solvent spread the fastest, indicating that the OD system can effectively inhibit the bouncing and rolling of droplets.

[0093] 4. Control effect on wheat scab

[0094] Table 8 The control effect of different preparations of metconazole on wheat scab

[0095]

[0096] Note: Different lowercase letters in the same column in the table indicate significant differences at the P<0.05 level tested by LSD method.

[0097] The results of indoor control efficacy test are shown in Table 8. All agents have control efficacy against wheat fusarium head blight, and the control efficacy of each agent gradually increases with the continuous increase of the mass concentration of the application. The control efficacy of the preparation prepared with methyl oleate as solvent oil is significantly higher than that of S-150 agent and commercially available agents. When the mass concentration of the active ingredient of the agent is 160μg / mL, the control efficacy of the methyl oleate system is 86.89%. The control efficacy of S-150 agent and commercially available agents is 73.77% and 67.21%, respectively.

[0098] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A synergistic metconazole, characterized in that The synergistic metconazole is prepared from the metconazole original drug into a metconazole dispersible oil suspension concentrate.

2. A method for preparing a metconazole dispersible oil suspension concentrate, characterized in that: The following steps are involved: The metconazole technical, emulsifier, thickener and solvent are mixed and then sequentially sheared and sand-milled to obtain the metconazole dispersible oil suspension.

3. The preparation method according to claim 1, characterized in that The mass ratio of the metconazole technical, the emulsifier, the thickener and the solvent is 8:8-15:1-3:74-81.

4. The preparation method according to claim 2, characterized in that The emulsifier is one or more of N600, EF68, and EF69.

5. The preparation method according to claim 4, characterized in that The emulsifier is N600.

6. The preparation method according to claim 2, characterized in that The thickener is one or more of organic bentonite, white carbon black, and modified hydrogenated castor oil.

7. The preparation method according to claim 2, characterized in that The solvent is methyl oleate or S-150 mineral oil.

8. The preparation method according to claim 2, characterized in that The solvent is methyl oleate.

9. The preparation method according to claim 1, characterized in that The particle size D of the metconazole dispersible oil suspension concentrate is 50 ≤5μm.

10. Use of the metconazole dispersible oil suspension according to claim 1 in drone pesticide application.

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