A pesticide composition containing a silicon-rich ring and thiamethoxam and its application in preventing and treating downy mildew

Abstract

The application relates to a pesticide composition containing silicon-rich rings and thiamethoxam and application thereof in prevention and treatment of downy mildew, and belongs to the technical field of agricultural pesticides. In the application, heat-sensitive silicon-rich ring raw medicine is coated with a capsule wall material to form microcapsules, so that the chemical stability of the active ingredient in the storage process is effectively improved. The results of potting test show that the branch number, effective branch number and fruiting number of the pepper plants treated with the pesticide composition are significantly higher than those of the single-dose treatment group, which indicates that the pesticide composition can promote the vegetative growth and reproductive growth of the pepper, help to build a high-yield plant type, and improve the yield potential of crops. Field test data show that the prevention and treatment effect of the pesticide composition on the pepper downy mildew reaches 90.2%, which is significantly better than that of the single-dose treatment group. This indicates that the combination of the silicon-rich rings and thiamethoxam plays a synergistic effect in the prevention and treatment of the pepper downy mildew.

Description

Technical Field

[0001] This invention relates to the field of agricultural pesticide technology, specifically to a pesticide composition containing silicone rings and thiamethoxam and its application in the control of downy mildew. Background Technology

[0002] Downy mildew is a plant disease caused by pathogens of the family Peronomycetes in the class Oomycetes, posing a serious threat to agricultural production worldwide. The pathogens are highly obligate parasitic, spread rapidly, and are prone to outbreaks under suitable conditions. Traditional control methods heavily rely on chemical pesticides, but the resulting problems of pesticide resistance, environmental residues, and ecological pressure are becoming increasingly prominent.

[0003] Currently, mainstream chemical agents for controlling downy mildew rely on a few limited mechanisms of action. Phenylamide agents (such as metalaxyl) work by inhibiting RNA polymerase; however, due to their single target, pathogens easily develop high levels of resistance through gene mutations in the target enzyme, leading to severely reduced efficacy or even complete ineffectiveness of these agents in many areas. Carboxylamide agents (such as dimethomorph) work by interfering with cell wall synthesis; although their mechanisms of action differ, resistant strains have been observed in the field, and their resistance mechanisms are related to changes in the function of transmembrane transport proteins. Methoxyacrylate agents (such as azoxystrobin) act on the mitochondrial respiratory chain of pathogens, offering excellent initial control, but resistance develops even more rapidly; specific point mutations in the pathogen's cytochrome b gene can lead to significant loss of efficacy. The resistance problem of these mainstream agents forces increased application dosages and frequencies, creating a vicious cycle.

[0004] Against this backdrop, the application of plant immune inducers and growth regulators offers new insights into disease control. Silica-containing compounds, as organosilicon compounds, are known to strengthen plant cell walls, promote silicon deposition to form physical barriers, and activate systemic resistance responses in plants. In agricultural practice, they are typically positioned as auxiliary health-promoting components rather than primary control agents. Thiamethoxam, a highly effective neonicotinoid insecticide, has a clearly defined mechanism of action: acting on nicotinic acetylcholine receptors in the insect nervous system. It is primarily used for pest control. Currently, there are no reports of combining a known insecticide (thiamethoxam) with a known synergist (silica-containing compounds) for the control of downy mildew. Summary of the Invention

[0005] In view of the above-mentioned prior art, the purpose of this invention is to provide a pesticide composition containing silicone rings and thiamethoxam and its application in the control of downy mildew.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a pesticide composition containing silicone and thiamethoxam, said pesticide composition comprising, by weight percentage: 5-15% silane technical grade, 5-15% thiamethoxam technical grade, 2-6% capsule wall material, 2-5% polycarboxylate, 1-3% TX-10, 0.1-0.3% xanthan gum, 3-6% ethylene glycol, 0.05-0.2% polyether-modified siloxane, 0.05-0.1% Kathon, and deionized water to bring the total to 100%.

[0007] The silicon-rich ring is coated with a capsule wall material to form microcapsules, and the thiamethoxam is dispersed in the system in the form of solid particles.

[0008] Preferably, the capsule wall material is selected from any one of ethyl cellulose, polyurea, polyurethane, or gelatin-gum arabic composite.

[0009] Preferably, the pesticide composition comprises the following components by weight percentage: 10% silanol technical grade, 10% thiamethoxam technical grade, 4% capsule wall material, 3.5% polycarboxylate, 1.5% TX-10, 0.2% xanthan gum, 4% ethylene glycol, 0.1% polyether-modified siloxane, 0.08% Kathon, and deionized water to bring the total to 100%.

[0010] In a second aspect, the present invention provides the use of the above-described pesticide composition in the preparation of pesticide formulations for the control of downy mildew.

[0011] In a third aspect, the present invention provides the application of the above-described pesticide composition in the preparation of pesticide formulations that promote branching and fruit number in chili peppers.

[0012] The application involves diluting the pesticide composition with water 500-1500 times and then spraying it on the leaves.

[0013] A third aspect of the present invention provides a method for preparing the above-mentioned pesticide composition, comprising the following steps: (1) Weigh the silicone-rich ring active ingredient and capsule wall material, add ethyl acetate, and mix to form oil phase A; mix water, TX-10 and polycarboxylate to form aqueous phase B; mix oil phase A and aqueous phase B to form oil-in-water (O / W) emulsion, remove ethyl acetate from the system, and obtain silicone-rich ring microcapsule suspension; (2) Add thiamethoxam technical to the microcapsule suspension obtained in step (1), and after dispersing evenly, obtain a mixed slurry containing microcapsules and thiamethoxam; (3) Add ethylene glycol and xanthan gum to the mixed slurry obtained in step (2), adjust the pH of the system to 6.0-7.0 with 10% citric acid aqueous solution, then add the prescribed amount of BYK-020 and Kathon, filter, and age to obtain the pesticide composition. The beneficial effects of this invention are: 1. This invention effectively improves the chemical stability of the active ingredient during storage by encapsulating the heat-sensitive silicon-rich ring active ingredient with a capsule wall material to form microcapsules. Under high-temperature accelerated storage conditions, the water separation rate of the formulation of this invention is less than 3%, exhibiting good suspension stability and homogeneity, facilitating use and storage, and improving the practicality and reliability of the formulation.

[0014] 2. The results of the pot experiment showed that the number of branches, effective branches and fruits of pepper plants treated with the pesticide composition of the present invention were significantly higher than those of the single-agent treatment group, indicating that the pesticide composition can promote the vegetative and reproductive growth of peppers, help to build a high-yield plant type and improve the crop yield potential.

[0015] 3. Field trial data showed that the pesticide composition of this invention achieved a control effect of 90.2% against downy mildew of peppers, slightly better than the control agent dimethomorph (88.5%), and significantly better than the single-agent treatment group. This indicates that the combination of siloxane and thiamethoxam exerted a synergistic effect in the control of downy mildew of peppers. Attached Figure Description

[0016] Figure 1 Pepper branching and result number phenotypes of peppers subjected to the pesticide composition prepared according to the embodiments of the present invention.

[0017] Figure 2 To investigate the field efficacy of controlling downy mildew in peppers. Detailed Implementation

[0018] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0019] The specific embodiments of the present invention will be described in further detail below with reference to examples. The following detailed descriptions are illustrative and intended to provide further explanation of this application, rather than limiting the scope of the invention.

[0020] The CAS number of the silanol used in the examples is 42003-39-4, and the CAS number of the thiamethoxam used is 153719-23-4.

[0021] Example 1: Preparation of pesticide compositions containing silicone rings and thiamethoxam 1.1 Formulation composition (by weight percentage) 10% silanol technical grade, 10% thiamethoxam technical grade, 4% capsule wall material (ethyl cellulose), 3.5% polycarboxylate (TERSPERSE 2700, Xianchuang Chemical), 1.5% TX-10, 0.2% xanthan gum (industrial grade), 4% ethylene glycol (industrial grade), 0.10% polyether-modified siloxane (BYK-020), 0.08% Kathon (1,2-benzisothiazolin-3-one, industrial grade), and deionized water to bring the total to 100%.

[0022] 1.2 Preparation method Step 1: Preparation of silica-rich ring microcapsule suspension Oil phase preparation: In a dry container, weigh the prescribed amounts of the silanol-containing active ingredient and the capsule wall material (ethyl cellulose), add 10.00% of the total mass of ethyl acetate, and mechanically stir at 500 rpm in a 40°C water bath until the active ingredient and capsule wall material are completely dissolved to obtain a homogeneous oil phase A. Cool oil phase A to 25°C for later use.

[0023] Aqueous phase preparation: In a 500 mL reactor, add deionized water and the prescribed amounts of TX-10 and polycarboxylate. Turn on the stirrer (300 rpm) and stir for 10 minutes until completely dissolved to obtain a homogeneous aqueous phase B.

[0024] Emulsification: Slowly add oil phase A dropwise to aqueous phase B while maintaining basic stirring at 300 rpm. After the addition is complete, rapidly increase the stirring speed to 8000 rpm and use a high-speed disperser (IKA ULTRA-TURRAX T25) to perform high-speed shear emulsification of the mixture for 5 minutes to form a water-in-oil (O / W) emulsion with uniform and stable particle size distribution.

[0025] Microcapsule Formation and Curing: The reaction system was transferred to a 250 mL three-necked round-bottom flask. Ethyl acetate was slowly distilled off the system under a 45°C water bath and a vacuum of -0.09 MPa. During this process, ethyl cellulose precipitated and deposited on the surface of the triazide silicon droplets, forming solid microcapsules. The system gradually changed from a milky white emulsion to a milky white suspension. After the reaction was complete, the system was naturally cooled to room temperature to obtain a silica-rich ring microcapsule suspension.

[0026] Step 2: Add thiamethoxam Premixing: Transfer the entire primary suspension of the above-mentioned silicocyclic microcapsule to a 1 L mixing tank. Start stirring (600 rpm) and slowly add the prescribed amount of thiamethoxam technical. After the addition is complete, increase the stirring speed to 1500 rpm and continue shearing and dispersing for 15 minutes to obtain a mixed slurry containing microcapsules and thiamethoxam.

[0027] Step 3: Post-processing Transfer the mixed slurry to a mixing tank and start stirring at 500 rpm. Add the prescribed amounts of ethylene glycol and xanthan gum sequentially. Adjust the pH of the system to 6.5 ± 0.2 with a 10% citric acid aqueous solution. Add the prescribed amounts of BYK-020 and Kathon, reduce the stirring speed to 300 rpm, and continue stirring for 30 minutes.

[0028] The filtrate was obtained by filtering through a 200-mesh nylon sieve. The filtrate was then transferred to a sealed container and aged at room temperature (25°C) for 48 hours to obtain a pesticide composition containing silicone rings and thiamethoxam.

[0029] Example 2: Preparation of pesticide compositions containing silicone rings and thiamethoxam The proportions of active ingredients were adjusted, with the amount of silicocyclic technical grade being 8% and the amount of thiamethoxam technical grade being 10%. The amount of capsule wall material was adjusted to 2.00%. The types, amounts, preparation process steps, and parameters of the remaining adjuvants were exactly the same as in Example 1.

[0030] Comparative Example 1: The same total active ingredient content as in Example 1 (10% silanol and 10% thiamethoxam) was used, but microencapsulation was not performed. The capsule wall material was removed from the formulation, and an equal amount of deionized water was added accordingly.

[0031] All raw materials and adjuvants were added to water at once and mixed to obtain a mixed slurry. The post-treatment of the mixed slurry was the same as in Example 1.

[0032] Comparative Example 2: Preparation of Pesticide Compositions The difference between Comparative Example 2 and Example 1 is that the formulation does not contain the active ingredient silicone rings. The specific preparation method of the pesticide composition is as follows: 1.1 Formulation composition (by weight percentage) Thiamethoxam technical grade 10%, polycarboxylate (TERSPERSE 2700, Xianchuang Chemical) 3.5%, TX-10 1.5%, xanthan gum (industrial grade) 0.2%, ethylene glycol (industrial grade) 4%, polyether-modified siloxane (BYK-020) 0.10%, Kathon (1,2-benzisothiazolin-3-one, industrial grade) 0.08%, deionized water to 100%.

[0033] 1.2 Preparation method 1. In a 500 mL reactor, add deionized water, the prescribed amount of TX-10, polycarboxylate and thiamethoxam technical grade, and stir continuously at 1500 rpm for 15 minutes to obtain a mixed slurry.

[0034] 2. Transfer the mixed slurry to a mixing tank and start stirring at 500 rpm. Add the prescribed amounts of ethylene glycol and xanthan gum sequentially. Adjust the pH of the system to 6.5 ± 0.2 with a 10% citric acid aqueous solution. Add the prescribed amounts of BYK-020 and Kathon, reduce the stirring speed to 300 rpm, and continue stirring for 30 minutes.

[0035] The filtrate was obtained by filtering through a 200-mesh nylon sieve. The filtrate was then transferred to a sealed container and aged at room temperature (25°C) for 48 hours to obtain a pesticide composition containing thiamethoxam.

[0036] Comparative Example 3: Preparation of Pesticide Compositions The difference between Comparative Example 3 and Example 1 is that the formulation does not contain the active ingredient thiamethoxam. The specific preparation method of the pesticide composition is as follows: 1.1 Formulation composition (by weight percentage) 10% silanol technical grade, 4% capsule wall material (ethyl cellulose), 3.5% polycarboxylate (TERSPERSE 2700, Xianchuang Chemical), 1.5% TX-10, 0.2% xanthan gum (industrial grade), 4% ethylene glycol (industrial grade), 0.10% polyether-modified siloxane (BYK-020), 0.08% Kathon (1,2-benzisothiazolin-3-one, industrial grade), and deionized water to bring the total to 100%.

[0037] 1.2 Preparation method Step 1: Preparation of silica-rich ring microcapsule suspension Oil phase preparation: In a dry container, weigh the prescribed amounts of the silanol-containing active ingredient and the capsule wall material (ethyl cellulose), add 10.00% of the total mass of ethyl acetate, and mechanically stir at 500 rpm in a 40°C water bath until the active ingredient and capsule wall material are completely dissolved to obtain a homogeneous oil phase A. Cool oil phase A to 25°C for later use.

[0038] Aqueous phase preparation: In a 500 mL reactor, add deionized water and the prescribed amounts of TX-10 and polycarboxylate. Turn on the stirrer (300 rpm) and stir for 10 minutes until completely dissolved to obtain a homogeneous aqueous phase B.

[0039] Emulsification: Slowly add oil phase A dropwise to aqueous phase B while maintaining basic stirring at 300 rpm. After the addition is complete, rapidly increase the stirring speed to 8000 rpm and use a high-speed disperser (IKA ULTRA-TURRAX T25) to perform high-speed shear emulsification of the mixture for 5 minutes to form a water-in-oil (O / W) emulsion with uniform and stable particle size distribution.

[0040] Microcapsule Formation and Curing: The reaction system was transferred to a 250 mL three-necked round-bottom flask. Ethyl acetate was slowly distilled off the system under a 45°C water bath and a vacuum of -0.09 MPa. During this process, ethyl cellulose precipitated and deposited on the surface of the triazide silicon droplets, forming solid microcapsules. The system gradually changed from a milky white emulsion to a milky white suspension. After the reaction was complete, the system was naturally cooled to room temperature to obtain a silica-rich ring microcapsule suspension.

[0041] Step 2: Post-processing Transfer the silanol microcapsule suspension to a mixing tank and start stirring at 500 rpm. Add the prescribed amounts of ethylene glycol and xanthan gum sequentially. Adjust the pH of the system to 6.5 ± 0.2 with a 10% citric acid aqueous solution. Add the prescribed amounts of BYK-020 and Kathon, reduce the stirring speed to 300 rpm, and continue stirring for 30 minutes.

[0042] The filtrate was obtained by filtering through a 200-mesh nylon sieve. The filtrate was then transferred to a sealed container and aged at room temperature (25°C) for 48 hours to obtain a silicon-containing ring-rich pesticide composition.

[0043] Experimental Example 1: Determination of Physicochemical Stability of Formulation 1. Thermal storage stability test The test was conducted in accordance with the national standard "Test Method for Thermal Storage Stability of Pesticides" (GB / T 19136-2021).

[0044] Method: The samples prepared in Example 1 and Comparative Example 1 were placed into 30 mL transparent glass screw-top bottles, sealed, and stored in a constant temperature drying oven at (54±2)℃ for 14 days. After removal, the samples were allowed to return to room temperature.

[0045] Determination of active ingredient decomposition rate: Samples were taken before and after heat storage, and the content of silanol was determined by high performance liquid chromatography (HPLC). Chromatographic conditions: C18 column; mobile phase: acetonitrile-0.1% phosphoric acid aqueous solution (60:40, v / v); detection wavelength: silanol 230 nm; column temperature 30℃; flow rate 1.0 mL / min. Decomposition rate (%) = [(content before heat storage - content after heat storage) / content before heat storage] × 100%.

[0046] Observation of pourability and water separation rate: After heat storage, invert the sample bottle and observe its fluidity and sedimentation at the bottom of the bottle. After standing for 24 hours, observe the volume of the clear liquid precipitated on the top layer and calculate the water separation rate: Water separation rate (%) = (volume of clear liquid precipitated on the top layer ÷ total volume of sample) × 100%.

[0047] The experiment was repeated three times, and the average value was calculated.

[0048] Table 1: Results of thermal storage stability test ((54±2)℃, 14 days) Note: "<3" indicates that no obvious water separation was observed in any of the three measurements or the volume of water separation was less than 3% of the total volume. The specific value was not accurately measured.

[0049] Conclusion: This invention utilizes microencapsulation technology to encapsulate and protect the thermosensitive component, the silicon-rich ring, resulting in a significantly lower decomposition rate under accelerated thermal storage conditions compared to conventional suspensions (Example 1 vs. Comparative Example 1), and also demonstrates significantly better overall physical stability and water separation rate of the formulation.

[0050] Experimental Example 2: Effect of application of the pesticide composition of the present invention on branching and number of fruits in chili peppers This embodiment aims to quantitatively evaluate the promoting effect of applying the pesticide composition described in this invention on the vegetative growth (branching) and reproductive growth (number of fruits) of peppers through a standardized pot experiment.

[0051] 1. Test materials The test crop was chili pepper, variety 'Sujiao No. 5'. After disinfection and germination, seeds were sown in seedling trays and cultivated in an artificial climate chamber (day / night 25℃ / 18℃, 14h light, relative humidity 60-70%). When seedlings had 4-5 true leaves, healthy seedlings with uniform growth were selected and transplanted into plastic pots with a top diameter of 18 cm and a height of 16 cm, one seedling per pot. The cultivation substrate was a mixed nutrient soil (peat moss:vermiculite:perlite = 2:1:1, v / v / v).

[0052] Test reagents: Treatment T1: The pesticide composition prepared in Example 1.

[0053] Treatment T2: The pesticide composition prepared in Comparative Example 2.

[0054] Treatment T3: The pesticide composition prepared in Comparative Example 3.

[0055] Experimental design: A completely randomized block design was adopted. There were 3 treatments, each with 6 replicates (i.e., 6 pots, 1 plant per pot), for a total of 18 pots.

[0056] 2. Test Methods Application treatment: All treatments are calculated based on an effective ingredient dosage of 150 g / ha and diluted with deionized water to the required concentration (approximately 1000 times dilution).

[0057] The first foliar spraying should be carried out 7 days after the chili seedlings are transplanted (after the seedling establishment period). Use a small manual sprayer to evenly spray both sides of the entire chili plant's leaves until the leaves are moist but not dripping.

[0058] Apply the pesticide a second time 21 days after transplanting, using the same method as the first time.

[0059] During the experiment, all plants were placed in the same artificial climate chamber under the same environmental conditions as during the seedling stage. Water and fertilizer management was uniform, keeping the substrate moist but not waterlogged, and no additional growth regulators were applied.

[0060] 3. Test Results Thirty-five days after transplanting, a branching count was conducted: the total number of all primary lateral branches originating from the base of the main stem (above the cotyledon node) of each pepper plant was counted, regardless of length; any visible branch was counted. Based on the branching count, only robust primary lateral branches ≥5 cm in length and with at least one fully expanded leaf were counted. These branches have strong photosynthetic capacity and are the main sites for fruit growth; therefore, they were defined as effective branches.

[0061] Sixty days after transplanting, a result count was conducted: the total number of fruits that had clearly set and enlarged on each plant and were ≥2 cm in length was counted.

[0062] Table 3: Effects of different treatments on chili pepper branching and results Statistical results showed that the number of branches and effective branches in the T1 treatment were significantly higher than those in other treatments, indicating that it effectively promoted the development of lateral branches in chili peppers and formed more robust and productive fruiting branches. Furthermore, the number of fruits produced in the T1 treatment was significantly higher than in other treatment groups, indicating that the T1 treatment significantly improved the fruit-setting capacity of individual plants. The experimental results demonstrate that the pesticide composition prepared in this invention has unique and significant advantages in promoting chili pepper growth and development, constructing a high-yielding plant type, and enhancing yield potential.

[0063] Experiment Example 3: Effect Test on Controlling Downy Mildew of Peppers 1. Experimental Design and Materials Experimental Location and Conditions: The experiment was conducted in the spring of 2024 in a chili-growing area of ​​Shouguang City, Shandong Province. The soil used was loam with moderate and uniform fertility. The previous crop was a non-solanaceous vegetable. All cultivation and management practices (water and fertilizer, pruning, etc.) were kept consistent except for pesticide treatment.

[0064] The test crop was chili pepper ('Sujiao No. 5'). Seedlings were cultivated in nursery pots until they had 6-7 true leaves. Healthy seedlings with uniform growth were selected for transplanting. The planting spacing was 40 cm × 60 cm. Each plot was 20 m². 2 A 1-meter-wide protective row is set up between the small sections, and an isolation zone is set up around the test site.

[0065] Test reagents: Example 1, Comparative Example 2, Comparative Example 3, and commercial control reagent 80% dimethomorph water-dispersible granules (WG), a total of 4 treatments, with an additional water control (CK).

[0066] Experimental design: A completely randomized block design was adopted, with a total of 5 treatments, each with 4 replicates, for a total of 20 plots.

[0067] Test pathogen: Diseased leaf tissue was cut from pepper leaves exhibiting typical downy mildew symptoms (with a white, frosty mold layer on the underside); fresh sporangia were scraped from the underside of leaves of diseased pepper seedlings, and a sporangia suspension was prepared using sterile water at 4°C. The concentration was adjusted to 5 × 10⁻⁶ using a hemocytometer. 4 Sporangia / mL.

[0068] Downy mildew is an obligate parasitic fungus and cannot be cultured artificially. Downy mildew sporangium suspensions should be prepared only when needed and used for inoculation immediately after preparation.

[0069] 2. Test Methods Application: All pesticide treatments are calculated based on an effective ingredient dosage of 150 g / ha, diluted with deionized water to the required concentration (approximately 1000 times dilution). For dimethomorph WG, the dosage is calculated at 200 g / ha. The first spray application should be performed after the chili pepper seedlings have established themselves. Use a manual sprayer to evenly spray both sides of the chili pepper leaves until just moistened.

[0070] Downy mildew inoculation: On the third day after application (i.e., 72 hours after application), use the sporangium suspension spray inoculation method to evenly inoculate the underside of the leaves of all treated plants.

[0071] Second application: Apply the second application 7 days after the first application.

[0072] The control area was sprayed with the same amount of clean water at the same time.

[0073] Record the weather conditions on the day of each application, and ensure there is no rainfall within 24 hours after application.

[0074] 3. Test Results Downy mildew survey: On the 10th day after inoculation with downy mildew, all leaves of each plant were surveyed and the disease severity was recorded.

[0075] Disease severity grading criteria: Grade 0, no lesions; Grade 1, lesion area ≤10% of leaf area; Grade 3, >10%~25%; Grade 5, >25%~50%; Grade 7, >50%~75%; Grade 9, >75%. Calculate the disease index and control effectiveness.

[0076] Disease index = [∑(number of diseased leaves at each level × level value) / (total number of leaves surveyed × highest level value)] × 100.

[0077] Prevention and control effect (%) = [(disease index of water control - disease index of treatment) / disease index of water control] × 100.

[0078] Table 4: Efficacy test of controlling downy mildew of peppers Experimental results show that the formulation of the present invention (Example 1) has a slightly better field control effect on downy mildew of pepper than the specific fungicide dimethomorph, and is significantly better than each control ratio, maintaining a high level of control over downy mildew.

[0079] The above description is merely a preferred embodiment of this application and is not intended to limit the application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications made within the spirit and principles of this application are not permitted. Equivalent substitutions and improvements should all be included within the scope of protection of this application.

Claims

1. A pesticide composition containing silane-containing rings and thiamethoxam, characterized in that, The pesticide composition comprises the following components by weight percentage: 5-15% silane technical grade, 5-15% thiamethoxam technical grade, 2-6% capsule wall material, 2-5% polycarboxylate, 1-3% TX-10, 0.1-0.3% xanthan gum, 3-6% ethylene glycol, 0.05-0.2% polyether-modified siloxane, 0.05-0.1% Kathon, and deionized water to bring the total to 100%.

2. The pesticide composition according to claim 1, characterized in that, The silicon-rich ring is coated with a capsule wall material to form microcapsules, and the thiamethoxam is dispersed in the system in the form of solid particles.

3. The pesticide composition according to claim 1, characterized in that, The capsule wall material is selected from any one of ethyl cellulose, polyurea, polyurethane, or gelatin-gum arabic composite.

4. The pesticide composition according to claim 1, characterized in that, The pesticide composition comprises the following components by weight percentage: 10% silanol technical grade, 10% thiamethoxam technical grade, 4% capsule wall material, 3.5% polycarboxylate, 1.5% TX-10, 0.2% xanthan gum, 4% ethylene glycol, 0.1% polyether-modified siloxane, 0.08% Kathon, and deionized water to bring the total to 100%.

5. The use of the pesticide composition according to any one of claims 1-4 in the preparation of pesticide formulations for controlling downy mildew.

6. The use of the pesticide composition according to any one of claims 1-4 in the preparation of pesticide formulations that promote branching and fruit number in chili peppers.

7. The application according to claim 5 or 6, characterized in that, The application involves diluting the pesticide composition with water 500-1500 times and then spraying it on the leaves.

8. The method for preparing the pesticide composition according to claim 1, characterized in that, Includes the following steps: (1) Weigh the silicone-rich ring active ingredient and capsule wall material, add ethyl acetate, and mix to form oil phase A; mix water, TX-10 and polycarboxylate to form aqueous phase B; mix oil phase A and aqueous phase B to form oil-in-water (O / W) emulsion, remove ethyl acetate from the system, and obtain silicone-rich ring microcapsule suspension; (2) Add thiamethoxam technical to the microcapsule suspension obtained in step (1), and after dispersing evenly, obtain a mixed slurry containing microcapsules and thiamethoxam; (3) Add ethylene glycol and xanthan gum to the mixed slurry obtained in step (2), adjust the pH of the system to 6.0-7.0 with 10% citric acid aqueous solution, add the prescribed amount of BYK-020 and Kathon, filter, and age to obtain the pesticide composition.

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