Herbicide containing indoxacarb and preparation method thereof
By modifying chitosan/γ-polyglutamic acid to encapsulate indenaxavir and herbicides, it forms a nanocarrier, solving the problem of poor performance of existing herbicides, achieving efficient herbicidal and pest control, and improving pesticides Stability and ease of use.
Patent Information
- Application Number
- CN202411222380.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-02
- Publication Date
- 2024-12-06
AI Technical Summary
The insecticidal and herbicidal properties of existing herbicides are poor, making it difficult to effectively prevent and control pests and weeds.
Modified chitosan/γ-polyglutamic acid encapsulates indenaxavir and herbicides, and wraps it through the preparation method of modified chitosan to form a nanocarrier, improves film formation and sustained release, and enhances pesticides Stability and insecticidal efficiency.
It extends the duration of pesticide efficacy, improves herbicidal efficiency and insecticidal efficiency, reduces environmental pollution, simplifies agricultural management processes, and improves agricultural production efficiency.
Smart Images
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Abstract
Description
Technical Field
[0001] The invention belongs to the field of pesticide preparation preparation, and particularly relates to an indoxacarb-containing herbicide and a preparation method thereof. Background Art
[0002] Indoxacarb is a broad-spectrum oxadiazine insecticide that blocks the sodium ion channels in insect nerve cells, causing the nerve cells to lose their function. It has a contact and stomach poison effect and can effectively control a variety of pests on crops such as grain, cotton, fruit, and vegetables. Herbicides are used to eliminate or inhibit the growth of weeds. The combination of the two can be used to carry out comprehensive control of pests and weeds on crops at the same time, reducing the frequency and cost of field management.
[0003] Patent document with patent publication number CN113519543A discloses an organic inhibitory rice herbicide, which is compounded by mixing pyrazosulfuron-methyl, dimethoate, bispyribac-sodium suspension and clodinafop-butyl, so that the herbicide has a wider weed control spectrum and can be used in different growth periods of rice. The herbicide and the insecticide can be compounded and mixed by clodinafop-butyl, and indoxacarb and lufenuron are added to emamectin benzoate, which expands the control range of pests and delays the resistance of pests. The herbicide and the insecticide are mixed so that pests in the field can be controlled while weeding, and the function is more diverse and easy to use. However, the herbicide still has the problem of poor performance such as insecticidal and herbicidal properties. Summary of the invention
[0004] In order to solve the problem that the existing herbicides in the background technology have poor insecticidal and weeding properties, the purpose of the present invention is to provide a herbicide containing indoxacarb and a preparation method thereof.
[0005] The purpose of the present invention can be achieved through the following technical solutions:
[0006] A method for preparing a herbicide containing indoxacarb, the operating steps of which are:
[0007] Dissolve indoxacarb and the herbicide in dichloromethane, then add dropwise to the modified chitosan / γ-polyglutamic acid mixed solution, stir for 30-40 minutes to obtain a mixed emulsion, add dropwise a 0.5% sodium tripolyphosphate aqueous solution to the mixed emulsion, continue stirring at room temperature for 1-2 hours, centrifuge at 8000 r / min for 10 minutes to obtain a herbicide precipitate containing indoxacarb, and freeze-dry to obtain the herbicide containing indoxacarb;
[0008] The dosage ratio of indoxacarb, herbicide, dichloromethane, modified chitosan / γ-polyglutamic acid mixed solution and sodium tripolyphosphate aqueous solution is 0.2-0.6 g: 1-1.5 g: 10 mL: 60 mL: 60 mL.
[0009] Furthermore, the herbicide is clodinafop-butyl.
[0010] Furthermore, the preparation method of the modified chitosan / γ-polyglutamic acid mixed solution is:
[0011] Weighing modified chitosan, dissolving it in an acetic acid solution with a volume concentration of 1% at room temperature to prepare a modified chitosan solution, weighing γ-polyglutamic acid and dissolving it in deionized water to prepare a γ-polyglutamic acid solution, adding the γ-polyglutamic acid solution dropwise to the modified chitosan solution, stirring continuously at 50° C. for 1.5-2 hours, and then cooling to room temperature to obtain a modified chitosan / γ-polyglutamic acid mixed solution;
[0012] Among them, the dosage ratio of modified chitosan, acetic acid solution, γ-polyglutamic acid and deionized water is 0.3-0.4g:30mL:0.3-0.4g:30mL.
[0013] Furthermore, the preparation method of the modified chitosan is:
[0014] Weigh chitosan in isopropanol, stir and dissolve it at 60-90°C for 6 hours, adjust the pH value to 8 with 0.25 mol / L NaOH solution during stirring to obtain a chitosan solution, add 2,3-epoxypropyltrimethylammonium chloride to the chitosan solution, stir and react at 60°C for 20 hours, after the reaction is completed, dialyze the solution for 3 days to remove unreacted 2,3-epoxypropyltrimethylammonium chloride, and finally freeze-dry it in vacuum for 48 hours to obtain modified chitosan;
[0015] The dosage ratio of chitosan to isopropanol is 2.5 g:100 mL; the dosage ratio of 2,3-epoxypropyltrimethylammonium chloride to chitosan solution is 3 g:100 mL.
[0016] Furthermore, the molecular weight of the chitosan is 60 KDa, and the degree of deacetylation is 90%.
[0017] Furthermore, a herbicide containing indoxacarb is prepared by the above preparation method.
[0018] Beneficial effects of the present invention:
[0019] 1. The present invention uses modified chitosan / γ-polyglutamic acid to wrap indoxacarb and herbicides. The modified chitosan and γ-polyglutamic acid are natural polymer materials with good film-forming properties and sustained-release properties. By wrapping indoxacarb and herbicides, their release rate can be slowed down and the duration of drug efficacy can be prolonged. The wrapped pesticides can better resist the influence of the external environment such as light, rain, etc., maintain the stability of their active ingredients, thereby improving the utilization rate and stability of the pesticides and improving the weed control efficiency. The modified chitosan and γ-polyglutamic acid are both biodegradable materials, which are friendly to the environment, can reduce the residue of pesticides in the environment, and reduce the pollution to soil, water bodies and ecosystems. The surface of the modified chitosan / γ-polyglutamic acid carries an electric charge, and the particles repel each other, and can be well dispersed in water, which improves the water solubility of the pesticide and makes the drug more easily contact with pests, thereby improving the insecticidal efficiency.
[0020] 2. The present invention uses epoxy quaternary ammonium salt to modify chitosan to increase the positive charge of the modified chitosan, so that the modified chitosan containing polypositive charge and the γ-polyglutamic acid containing polynegative charge can be more tightly combined, thereby improving the stability of the nanocarrier, and the water solubility and bactericidal property of the modified chitosan are significantly improved, which improves the poor water solubility of chitosan and also improves the bactericidal property of the herbicide.
[0021] 3. The present invention integrates herbicides and insecticides into one, achieving the dual functions of weed control and pest control, enriching the application scenarios of pesticides and improving their ease of use, simplifying the operation process, and improving agricultural production efficiency. DETAILED DESCRIPTION
[0022] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0023] Example 1
[0024] This embodiment describes a method for preparing a herbicide containing indoxacarb, and the operating steps are as follows:
[0025] 0.2 g of indoxacarb and 1 g of clodinafop-butyl were dissolved in 10 mL of dichloromethane, and then added dropwise to 60 mL of modified chitosan / γ-polyglutamic acid mixed solution, stirred for 30 min to obtain a mixed emulsion, 60 mL of 0.5% sodium tripolyphosphate aqueous solution was added dropwise to the mixed emulsion, stirred continuously for 1 h at room temperature, centrifuged at 8000 r / min for 10 min to obtain a herbicide precipitate containing indoxacarb, and freeze-dried to obtain the herbicide containing indoxacarb.
[0026] The preparation method of the modified chitosan / γ-polyglutamic acid mixed solution is:
[0027] Weigh 0.3 g of modified chitosan and dissolve it in 30 mL of 1% acetic acid solution at room temperature to prepare a modified chitosan solution. Weigh 0.3 g of γ-polyglutamic acid and dissolve it in 30 mL of deionized water to prepare a γ-polyglutamic acid solution. Add the γ-polyglutamic acid solution dropwise to the modified chitosan solution, stir continuously at 50° C. for 1.5 h, and then cool to room temperature to obtain a modified chitosan / γ-polyglutamic acid mixed solution.
[0028] The preparation method of the modified chitosan is:
[0029] Weigh 2.5 g of chitosan (molecular weight 60 KDa, deacetylation degree 90%) in 100 mL of isopropanol, stir and dissolve at 60 ° C for 6 h, adjust the pH value to 8 with 0.25 mol / L NaOH solution during stirring to obtain a chitosan solution, add 3 g of 2,3-epoxypropyltrimethylammonium chloride to 100 mL of the chitosan solution, stir and react at 60 ° C for 20 h, after the reaction is completed, dialyze the solution for 3 days to remove unreacted 2,3-epoxypropyltrimethylammonium chloride, and finally freeze-dry in vacuum for 48 h to obtain modified chitosan.
[0030] Example 2
[0031] This embodiment describes a method for preparing a herbicide containing indoxacarb, and the operating steps are as follows:
[0032] 0.4 g of indoxacarb and 1.25 g of clodinafop-butyl were dissolved in 10 mL of dichloromethane, and then added dropwise to 60 mL of modified chitosan / γ-polyglutamic acid mixed solution, stirred for 30 min to obtain a mixed emulsion, 60 mL of 0.5% sodium tripolyphosphate aqueous solution was added dropwise to the mixed emulsion, and the mixture was stirred continuously for 1.5 h at room temperature, and centrifuged at 8000 r / min for 10 min to obtain a herbicide precipitate containing indoxacarb, which was freeze-dried to obtain a herbicide containing indoxacarb.
[0033] The preparation method of the modified chitosan / γ-polyglutamic acid mixed solution is:
[0034] Weigh 0.3 g of modified chitosan and dissolve it in 30 mL of 1% acetic acid solution at room temperature to prepare a modified chitosan solution. Weigh 0.3 g of γ-polyglutamic acid and dissolve it in 30 mL of deionized water to prepare a γ-polyglutamic acid solution. Add the γ-polyglutamic acid solution dropwise to the modified chitosan solution, stir continuously at 50° C. for 1.5 h, and then cool to room temperature to obtain a modified chitosan / γ-polyglutamic acid mixed solution.
[0035] The preparation method of the modified chitosan is:
[0036] Weigh 2.5 g of chitosan (molecular weight 60 KDa, deacetylation degree 90%) in 100 mL of isopropanol, stir and dissolve it at 80 ° C for 6 h, adjust the pH value to 8 with 0.25 mol / L NaOH solution during stirring to obtain a chitosan solution, add 3 g of 2,3-epoxypropyltrimethylammonium chloride to 100 mL of the chitosan solution, stir and react at 60 ° C for 20 h, after the reaction is completed, dialyze the solution for 3 days to remove unreacted 2,3-epoxypropyltrimethylammonium chloride, and finally freeze-dry it in vacuum for 48 h to obtain modified chitosan.
[0037] Example 3
[0038] This embodiment describes a method for preparing a herbicide containing indoxacarb, and the operating steps are as follows:
[0039] 0.6 g of indoxacarb and 1.5 g of clodinafop-butyl were dissolved in 10 mL of dichloromethane, and then added dropwise to 60 mL of modified chitosan / γ-polyglutamic acid mixed solution, stirred for 40 min to obtain a mixed emulsion, 60 mL of 0.5% sodium tripolyphosphate aqueous solution was added dropwise to the mixed emulsion, stirred continuously for 2 h at room temperature, centrifuged at 8000 r / min for 10 min to obtain a herbicide precipitate containing indoxacarb, and freeze-dried to obtain the herbicide containing indoxacarb.
[0040] The preparation method of the modified chitosan / γ-polyglutamic acid mixed solution is:
[0041] Weigh 0.4 g of modified chitosan and dissolve it in 30 mL of 1% acetic acid solution at room temperature to prepare a modified chitosan solution. Weigh 0.4 g of γ-polyglutamic acid and dissolve it in 30 mL of deionized water to prepare a γ-polyglutamic acid solution. Add the γ-polyglutamic acid solution dropwise to the modified chitosan solution, stir continuously at 50° C. for 2 h, and then cool to room temperature to obtain a modified chitosan / γ-polyglutamic acid mixed solution.
[0042] The preparation method of the modified chitosan is:
[0043] Weigh 2.5 g of chitosan (molecular weight 60 KDa, deacetylation degree 90%) in 100 mL of isopropanol, stir and dissolve at 90 ° C for 6 h, adjust the pH to 8 with 0.25 mol / L NaOH solution during stirring to obtain a chitosan solution, add 3 g of 2,3-epoxypropyltrimethylammonium chloride to 100 mL of the chitosan solution, stir and react at 60 ° C for 20 h, after the reaction is completed, dialyze the solution for 3 days to remove unreacted 2,3-epoxypropyltrimethylammonium chloride, and finally freeze-dry in vacuum for 48 h to obtain modified chitosan.
[0044] Comparative Example 1
[0045] The rest is the same as Example 1, except that the modified chitosan in Example 1 is replaced by chitosan, and the molecular weight of chitosan is 60 KDa and the degree of deacetylation is 90%.
[0046] Comparative Example 2
[0047] This comparative example describes a method for preparing a herbicide containing indoxacarb, and its operating steps are:
[0048] 0.2 g of indoxacarb and 1 g of clodinafop-butyl were added into a stirring tank, and the mixture was stirred at 200 rpm for 1 hour to obtain a herbicide containing indoxacarb.
[0049] The herbicides prepared in Examples 1-3 and Comparative Examples 1 and 2 were tested for performance, and the items are as follows:
[0050] 1. Bactericidal performance: 20 g of the herbicides prepared in Examples 1 to 3 and Comparative Example 1 were dissolved in 100 mL of anhydrous ethanol, diluted with water and applied. The volume of the herbicide diluted with water per mu of land was 10 L. Referring to "GB / T17980.19-2000 Guidelines for Field Efficacy Tests of Pesticides (I) Fungicides for Control of Rice Leaf Diseases", the area of each zone was 30 m2, 4 replicates were set, and the pesticide was applied twice, with an interval of 7 days between each application. The pesticides were investigated 7d and 14d after each application, respectively. The classification was performed according to the relevant data investigation standard, the disease index was statistically calculated, and the control effect was calculated. The results are shown in Table 1.
[0051] 2. Herbicidal activity: 20 g of the herbicides prepared in Examples 1 to 3 and Comparative Examples 1 and 2 were dissolved in 100 mL of anhydrous ethanol, diluted with water and applied. The volume of the diluted herbicide per acre was 10 L, and sprayed on Bermuda grass planted outdoors. The area of each area was 30 m2, and 4 replicates were set up. The application was conducted twice, with an interval of 7 days between each application. The effects of the herbicides on the growth of Bermuda grass were investigated 7 days and 14 days after each application. The results are shown in Table 2.
[0052] 3. Insecticidal activity: 20 g of the herbicides prepared in Examples 1 to 3 and Comparative Examples 1 and 2 were dissolved in 100 mL of anhydrous ethanol, diluted with water and applied. The volume of the herbicide after dilution with water was 10 L per acre of land, and sprayed on cucumbers planted in a greenhouse. The control effect on cucumber whiteflies was investigated 3 days after the application of the drug. The results are shown in Table 3.
[0053] 4. Photodegradation resistance: The herbicides prepared in Examples 1 to 3 and Comparative Examples 1 and 2 were dissolved in anhydrous ethanol to prepare a 0.1 mg / mL reaction solution. 10 mL of the reaction solution was placed in a quartz tube of about 15 mL and illuminated under a mercury lamp. Samples were taken at regular intervals and stored in the dark for testing. The residual contents of indoxacarb and clodinafop-butyl were determined using an ultraviolet spectrophotometer, and the photolysis rate was calculated. Photolysis rate (%) = (residual amount of dark control - residual amount of light treatment / residual amount of dark control) × 100. The results are shown in Table 4.
[0054] Table 1
[0055]
[0056] It can be seen from the test results in Table 1 that the control effect of Examples 1-3 on rice blast is much higher than that of Comparative Example 1, and the control effect can still reach more than 70% 14 days after application, with a long lasting effect, indicating that quaternary ammonium salt modification of chitosan during the preparation of the herbicide is beneficial to improving the bactericidal performance of the herbicide.
[0057] Table 2
[0058]
[0059] From the test results in Table 2, it can be seen that the control effects of Examples 1-3 on Bermuda grass are higher than those of Comparative Examples 1 and 2, indicating that the use of modified chitosan / γ-polyglutamic acid to wrap indoxacarb and herbicides can maintain the stability of their active ingredients and improve the weed control efficiency; the control effect of Comparative Example 1 is lower than that of Example 1, indicating that after the chitosan is quaternized, the γ-polyglutamic acid is more tightly bound, which improves the stability and the weed control efficiency; comparing Comparative Example 1 with Comparative Example 2, it is shown that the use of chitosan / γ-polyglutamic acid to wrap indoxacarb and herbicides can also improve their weed control effects.
[0060] Table 3
[0061]
[0062]
[0063] From the test results in Table 3, it can be seen that Examples 1-3 and Comparative Examples 1 and 2 are all effective against cucumber whitefly, indicating that adding indoxacarb to the herbicide can make the herbicide have insecticidal properties; the control effect of Example 1 against melon whitefly is higher than that of Comparative Example 2, indicating that the modified chitosan / γ-polyglutamic acid encapsulation of indoxacarb and the herbicide can maintain the stability of their active ingredients, thereby improving the insecticidal effect and reducing the dosage.
[0064] Table 4
[0065]
[0066] From the test results in Table 4, it can be seen that the anti-photolysis rates of Examples 1-3 are better than those of Comparative Examples 1 and 2, indicating that the use of modified chitosan / γ-polyglutamic acid to encapsulate indoxacarb and herbicides can improve the photostability of the pesticide.
[0067] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.
[0068] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A method for preparing a herbicide containing indoxacarb, characterized in that: The steps include: Dissolve indoxacarb and herbicide in dichloromethane, add dropwise to the modified chitosan / γ-polyglutamic acid mixed solution, stir for 30-40 minutes to obtain a mixed emulsion, add sodium tripolyphosphate aqueous solution to the mixed emulsion, stir at room temperature, centrifuge to obtain a herbicide precipitate containing indoxacarb, and freeze-dry to obtain the herbicide containing indoxacarb.
2. The method for preparing a herbicide containing indoxacarb according to claim 1, characterized in that: The room temperature stirring time is 1-2 hours, the centrifugal speed is 8000 r / min, the centrifugal time is 10 minutes, and the mass concentration of the sodium tripolyphosphate aqueous solution is 0.5%.
3. The method for preparing a herbicide containing indoxacarb according to claim 1, characterized in that: The dosage ratio of indoxacarb, herbicide, dichloromethane, modified chitosan / γ-polyglutamic acid mixed solution and sodium tripolyphosphate aqueous solution is 0.2-0.6g:1-1.5g:10mL:60mL:60mL.
4. The method for preparing a herbicide containing indoxacarb according to claim 1, characterized in that: The herbicide is clodinafop-butyl.
5. The method for preparing a herbicide containing indoxacarb according to claim 1, characterized in that: The preparation method of the modified chitosan / γ-polyglutamic acid mixed solution is: Weigh the modified chitosan, dissolve it in acetic acid solution at room temperature to prepare a modified chitosan solution, weigh γ-polyglutamic acid and dissolve it in deionized water to prepare a γ-polyglutamic acid solution, add the γ-polyglutamic acid solution dropwise to the modified chitosan solution, stir at 50° C. for 1.5-2 h, and then cool to room temperature to obtain a modified chitosan / γ-polyglutamic acid mixed solution.
6. The method for preparing a herbicide containing indoxacarb according to claim 5, characterized in that: The usage ratio of the modified chitosan, acetic acid solution, gamma-polyglutamic acid and deionized water is 0.3-0.4 g: 30 mL: 0.3-0.4 g: 30 mL; the volume concentration of the acetic acid solution is 1%.
7. The method for preparing a herbicide containing indoxacarb according to claim 5, characterized in that: The preparation method of the modified chitosan is: Weigh chitosan in isopropanol, stir at 60℃-90℃ for 6h, adjust the pH to 8 with 0.25mol / L NaOH solution to obtain chitosan solution, add 2,3-epoxypropyltrimethylammonium chloride to the chitosan solution, stir at 60℃ for 20h, dialyze for 3d, and vacuum freeze-dry for 48h to obtain modified chitosan.
8. The method for preparing a herbicide containing indoxacarb according to claim 7, characterized in that: The usage ratio of chitosan to isopropanol is 2.5 g:100 mL; the usage ratio of 2,3-epoxypropyltrimethylammonium chloride to chitosan solution is 3 g:100 mL.
9. The method for preparing a herbicide containing indoxacarb according to claim 7, characterized in that: The chitosan has a molecular weight of 60 KDa and a deacetylation degree of 90%.
10. A herbicide containing indoxacarb, characterized in that: Prepared by the preparation method according to any one of claims 1 to 9.