A miticidal composition and use thereof

Abstract

This invention belongs to the field of pesticide technology and relates to an acaricidal composition and its application. The acaricidal composition comprises active ingredient A and active ingredient B; active ingredient A is a compound of formula (I), and active ingredient B is abamectin. The acaricidal composition can control a variety of mites, exhibits a synergistic effect within a certain proportion range, and can reduce the dosage, lower the cost, prolong the duration of effectiveness, and delay the development of pesticide resistance in mites.

Description

[0001] This invention application is a divisional application with application number 202310577829.7, application date 20230522, and invention title "An acaricide composition and its application". Technical Field

[0002] This invention belongs to the field of pesticides, specifically relating to an acaricide composition and its application. Background Technology

[0003] The chemical name of compound (I) is (4'-chloro-6-fluoro-4-methyl-[1,1'-biphenyl]-3-yl)(2,2,2-trifluoroethyl) sulfide, and its chemical structure is as follows:

[0004]

[0005] Pyridaben is a mitochondrial electron transport inhibitor that mainly inhibits electron transport at the coenzyme Q0 site. This agent has a novel structure and a unique mechanism of action. It is highly effective and broad-spectrum in killing mites and is currently widely used in the field. However, long-term, large-scale, and single-use application can easily lead to the development of mites' resistance.

[0006] Avermectin is a highly effective, broad-spectrum antibiotic insecticide and acaricide, belonging to the macrolide class of compounds. It has stomach poison and contact effects on mites and insects. When sprayed on the leaf surface, it decomposes and dissipates rapidly. The active ingredients that penetrate into the plant parenchyma can remain in the tissue for a longer period and have a conductive effect, resulting in long residual efficacy against harmful mites and insects that feed on and damage plant tissues.

[0007] Therefore, in order to minimize the development of resistance in mites to abamectin and pyridaben and improve the control effect on mites, it is necessary to use abamectin and pyridaben in combination to extend the life of the pesticides. Summary of the Invention

[0008] To address the aforementioned problems in the prior art, the present invention provides an acaricidal composition that can effectively prevent mites, exhibits a synergistic effect within a certain proportion range, reduces usage costs, decreases dosage, prolongs the duration of effectiveness, and delays the development of drug resistance.

[0009] To solve the above technical problems, the present invention provides the following technical solution: an acaricidal composition comprising active ingredient A and active ingredient B, wherein active ingredient A is a compound of formula (I):

[0010] Active ingredient B is either pyridaben or avermectin;

[0011] Furthermore, the mass ratio of active ingredient A to active ingredient B is 1:50 to 50:1;

[0012] Furthermore, the mass ratio of active ingredient A to active ingredient B is 1:40 to 30:1;

[0013] Furthermore, the mass ratio of active ingredient A to active ingredient B is 1:30 to 30:1;

[0014] Furthermore, the mass ratio of the compound of formula (I) to pyridaben is 1:40 to 25:1;

[0015] Further, the mass ratio of the compound of formula (I) to pyridaben is 1:40, 1:25, 1:20, 1:14, 1:10, 1:8, 5:3, 1:1, 7:1, 3:1, 17:2, 10:1, 15:1, 25:1;

[0016] Furthermore, the mass ratio of the compound of formula (I) to pyridaben is 1:25 to 15:1;

[0017] Furthermore, the mass ratio of the compound of formula (I) to pyridaben is 1:25, 1:20, 1:14, 1:10, 1:8, 5:3, 1:1, 7:1, 3:1, 17:2, 10:1, or 15:1;

[0018] Furthermore, the mass ratio of the compound of formula (I) to avermectin is 1:30 to 30:1;

[0019] Further, the mass ratio of the compound of formula (I) to avermectin is 1:30, 1:25, 1:18, 1:12, 1:10, 1:7, 1:4, 5:1, 3:2, 3:1, 6:1, 15:2, 10:1, 15:1, 16:1, or 30:1;

[0020] Furthermore, the mass ratio of the compound of formula (I) to avermectin is 1:25 to 30:1;

[0021] Further, the mass ratio of the compound of formula (I) to avermectin is 1:25, 1:18, 1:12, 1:10, 1:7, 1:4, 5:1, 3:2, 3:1, 6:1, 15:2, 10:1, 15:1, 16:1, or 30:1;

[0022] Furthermore, based on a total weight of 100 wt% of the acaricidal composition, the sum of the contents of active ingredient A and active ingredient B in the acaricidal composition is 1 to 95 wt%.

[0023] Furthermore, the sum of the contents of active ingredient A and active ingredient B in the acaricide composition is 2-80 wt%.

[0024] Furthermore, in addition to the active ingredient, the acaricide composition also includes agriculturally acceptable auxiliary ingredients, which are selected from one or more of the following: wetting agents, dispersants, emulsifiers, thickeners, disintegrants, antifreeze agents, defoamers, solvents, preservatives, stabilizers, synergists, or carriers.

[0025] The wetting agent is selected from one or more of the following: alkylbenzene sulfonates, alkylnaphthalene sulfonates, lignin sulfonates, sodium dodecyl sulfate, sodium dioctyl succinate sulfonate, α-olefin sulfonates, alkylphenol polyoxyethylene ethers, castor oil polyoxyethylene ethers, ethylene glycol polyoxyethylene polyoxypropylene ethers, fatty alcohol ethoxylates, isomeric alcohol polyoxyethylene ethers, sodium fatty alcohol polyoxyethylene ether sulfate, silkworm excrement, soapberry powder, soapberry powder, SOPA, detergents, emulsifiers 2000 series, and wetting and penetrating agents F; and / or

[0026] The dispersant is selected from one or more of the following: lignin sulfonates, alkyl naphthalene sulfonates formaldehyde condensates, naphthalene sulfonates, tristyrylphenol ethoxylate phosphates, block polyether phosphates, arylphenol polyoxyethylene ether sulfates, fatty alcohol ethoxylates, alkylphenol polyoxyethylene ethers, alkylphenol polyoxyethylene ether methyl ether condensates sulfates, fatty amine polyoxyethylene ethers, glycerol fatty acid ester polyoxyethylene ethers, polycarboxylates, polyacrylic acids, phosphates, EO-PO block copolymers, and EO-PO graft copolymers; and / or

[0027] The emulsifier is selected from one or more of the following: calcium dodecylbenzenesulfonate, amine dodecylbenzenesulfonate, alkylphenol formaldehyde resin polyoxyethylene ether, phenethylphenol polyoxyethylene polyoxypropylene ether, benzylphenol polyoxyethylene ether, fatty alcohol ethylene oxide-propylene oxide copolymer, styrene-phenol polyoxyethylene ether, castor oil polyoxyethylene ether, alkylphenol polyoxyethylene ether, alkylphenol ether phosphate, and styrene-phenol polyoxyethylene ether phosphate; and / or

[0028] The thickener is selected from one or more of xanthan gum, organobentonite, gum arabic, sodium alginate, magnesium aluminum silicate, carboxymethyl cellulose, and silica; and / or

[0029] The disintegrant is selected from one or more of sodium sulfate, ammonium sulfate, aluminum chloride, sodium chloride, ammonium chloride, bentonite, glucose, sucrose, starch, cellulose, urea, sodium carbonate, sodium bicarbonate, citric acid, and tartaric acid; and / or

[0030] Antifreeze is selected from one or more of alcohols, alcohol ethers, chlorinated hydrocarbons, and inorganic salts; and / or

[0031] Defoamer selected from C 10 -C 20 Saturated fatty acid compounds, silicone oil, silicone compounds, C8-C 10 One or more of the fatty alcohols; and / or

[0032] The solvent is selected from one or more of benzene, toluene, xylene, trimethylbenzene, mesitylene, methanol, ethanol, isopropanol, n-butanol, isooctanol, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethyldecylamide, N-methylpyrrolidone, cyclohexanone, propylene carbonate, hydrocarbon carbonate, diesel oil, solvent oil, vegetable oil, vegetable oil derivatives, and water; and / or

[0033] The preservative is selected from one or more of the following: propionic acid, sodium propionate, sorbic acid, sodium sorbate, potassium sorbate, benzoic acid, sodium benzoate, sodium p-hydroxybenzoate, methyl p-hydroxybenzoate, ethyl p-hydroxybenzoate, propyl p-hydroxybenzoate, butyl p-hydroxybenzoate, isothiazolinones, benzimidazoles, iodopropyl groups, pyridinethiones, Kathon, and 1,2-benzisothiazolin-3-one; and / or

[0034] The stabilizer is selected from one or more of the following: disodium hydrogen phosphate, oxalic acid, succinic acid, adipic acid, borax, 2,6-di-tert-butyl-p-cresol, triethanolamine oleate, epoxidized vegetable oil, kaolin, bentonite, attapulgite, silica, talc, montmorillonite, and starch; and / or

[0035] Synergists are selected from synergistic phosphorus, synergistic ether, synergistic amine; and / or

[0036] The carrier is selected from one or more of the following: ammonium salts, ground natural minerals, ground artificial minerals, silicates, resins, waxes, solid fertilizers, water, organic solvents, mineral oils, vegetable oils, and vegetable oil derivatives.

[0037] Furthermore, the acaricide composition can be prepared into an agriculturally permissible formulation, wherein the formulation is selected from solid and / or liquid formulations;

[0038] The solid dosage forms include powders, granules, balls, tablets, strips, wettable powders, oil-dispersible powders, emulsion powders, water-dispersible granules, emulsion granules, water-dispersible tablets, soluble powders, soluble tablets, or soluble granules.

[0039] The liquid formulations include soluble agents, colloids, oils, spreading oils, emulsions, latexes, dispersible liquids, ointments, water emulsions, oil emulsions, microemulsions, lipid suspensions, microcapsule suspensions, oil suspensions, dispersible oil suspensions, suspensions, microcapsule suspension-suspension agents, microcapsule suspension-water emulsions, or microcapsule suspension-suspension emulsions.

[0040] Furthermore, the solid formulation is selected from wettable powder, water-dispersible granules, and soluble granules; the liquid formulation is selected from emulsifiable concentrate, water emulsion, suspension concentrate, suspension emulsion, microemulsion, and dispersible oil suspension.

[0041] Application of an acaricidal composition for the control of harmful mites;

[0042] Furthermore, the harmful mites are root mites or leaf mites;

[0043] Furthermore, the root mite is *Tetranychus spinosa*, and the leaf mite is *Tetranychus sanguinea*, *Tetranychus cinnabarinus*, *Tetranychus two-spotted*, or *Tetranychus truncatula*.

[0044] Furthermore, the acaricidal composition and / or its formulation are applied at an effective dose to the mites that need to be controlled or the medium in which they grow.

[0045] The beneficial effects of this invention are:

[0046] (1) The compound acaricide of the present invention has a significant synergistic effect compared with the single agent, thus improving the control effect;

[0047] (2) The compound acaricide of the present invention improves the control effect while reducing the amount of drug used, reducing costs and reducing residues;

[0048] (3) The compound acaricide of the present invention has a long-lasting effect and can effectively control the damage of mites to crops throughout the entire growth period. It is safe for crops, non-target organisms, beneficial organisms and natural enemies, and has the effect of increasing yield and ensuring income. Detailed Implementation

[0049] To make the technical solution, objectives and advantages of the present invention clearer, the present invention is described with reference to the following specific embodiments. However, the present invention can be implemented in various forms and should not be limited to the embodiments described herein.

[0050] Formulation preparation example:

[0051] Preparation Example 1: 35% Compound (I)·Pyridaben Suspension (20:15)

[0052] Preparation formula: 20% compound (Ⅰ), 15% pyridaben, 2% sodium lignosulfonate, 3% fatty amine polyoxyethylene ether, 2% polycarboxylate, 0.5% naphthalene sulfonate, 0.5% methyl paraben, 0.2% xanthan gum, 1% magnesium aluminum silicate, 3.5% propylene glycol, 0.2% silicone defoamer, deionized water to make up the balance;

[0053] Preparation method: According to the formulation ratio in the example, the active ingredients, surfactants and other functional additives are placed in the reaction vessel in sequence, deionized water is added and mixed evenly, and then subjected to high-speed shearing, wet sand milling and finally homogenization filtration to obtain the suspension product.

[0054] Preparation Example 2: 22% Formula (I) compound avermectin suspension (18:4)

[0055] Preparation formula: 18% compound of formula (I), 4% abamectin, 4% castor oil polyoxyethylene ether phosphate, 1.5% block polyether, 0.5% sodium lignosulfonate, 0.2% sodium sorbate, 0.1% Kathon, 0.2% xanthan gum, 1% magnesium aluminum silicate, 4.5% propylene glycol, 0.4% dimethyl silicone oil, 0.5% BHT, deionized water to make up the balance;

[0056] Preparation method: Same as in preparation example 1.

[0057] Preparation Example 3: 8% Compound (I)·Pyridaben Emulsifiable Concentrate (5:3)

[0058] Preparation formula: 5% compound of formula (I), 3% pyridaben, 14% propylene carbonate, 15% DMDA, 15% cyclohexanone, 3% calcium dodecylbenzenesulfonate, 12% styrene-phenol polyoxyethylene ether, solvent oil to make up the balance;

[0059] Preparation method: Add the active ingredients to the cosolvent according to the formulation ratio of the example, and add surfactants and other functional additives thereto. Stir and mix evenly in a stirring mixing tank to obtain the emulsifiable oil product.

[0060] Preparation Example 4: 8% of formula (I) compound avermectin emulsifiable concentrate (5.5:2.5)

[0061] Preparation formula: 5.5% compound of formula (I), 2.5% abamectin, 1% BHT, 18% propylene carbonate, 15% DMF, 15% cyclohexanone, 4% calcium dodecylbenzenesulfonate, 12% fatty alcohol polyoxyethylene ether, and methyl oleate to make up the balance;

[0062] Preparation method: Same as in preparation example 3.

[0063] Preparation Example 5: 45% Compound (I)·Pyridaben Wettable Powder (30:15)

[0064] Preparation formula: 30% of compound (Ⅰ), 15% pyridaben, 11% sodium lignosulfonate, 2% sodium dodecyl sulfate, 4.5% naphthalene sulfonate, 8% ammonium sulfate, 4.5% silica, and kaolin to make up the balance;

[0065] Preparation method: According to the formulation ratio in the example, the active ingredients are added to the carrier, and surfactants and other functional additives are added thereto. After mixing, the mixture is pulverized by air jet and then mixed again to obtain a wettable powder product.

[0066] Preparation Example 6: 5.5% Avermectin water emulsion of formula (I) (5:0.5)

[0067] Preparation formula: 5% compound (Ⅰ), 0.5% abamectin, 5% xylene, 20% cyclohexanone, 1% BHT, 1% fatty alcohol polyoxyethylene ether phosphate, 7.5% ethylene oxide-propylene oxide copolymer, 5% ethylene glycol, 0.2% silicone defoamer, 0.1% xanthan gum, 0.2% benzoic acid, deionized water to make up the balance;

[0068] Preparation method: According to the formulation ratio in the example, the active ingredient is dissolved in the solvent and an emulsifier is added to form a homogeneous oil phase. Deionized water and antifreeze are mixed together to form a homogeneous aqueous phase. Under high-speed shearing, the aqueous phase is added to the oil phase. Finally, thickener, preservative and defoamer are added to form a well-dispersed water emulsion product.

[0069] Indoor toxicity

[0070] Indoor Example 1

[0071] Example references: Pesticide Indoor Bioassay Test Guidelines Part 7: Determination of Combined Effects of Mixtures NY / T1154.7-2006 and Part 13: Pesticide Indoor Bioassay Test Guidelines Insecticides Part 13: Leaf Disc Spray Method NY / T1154.13-2008.

[0072] Test insect source: Tetranychus carmine (bred at the R&D center), selected female adult mites kept indoors and in the same physiological state. Temperature: (25±1)℃. Relative humidity: 65%±5%, photoperiod: 16 / 8h (L / D);

[0073] Preparation of test materials: Select broad bean leaves with uniform growth, make leaf discs with a punch, place a wet sponge block in the petri dish, place filter paper on it, and place leaf discs on the filter paper, with 2 leaf discs per dish. Inoculate 15 adult mites raised indoors onto the leaf discs per dish.

[0074] Drug preparation: Dissolve the drug in acetone, then dilute with 0.1% Tween-80 aqueous solution. Prepare single-dose stock solutions separately, and design the ratio according to the purpose of mixing and drug activity. Prepare five series of mass concentrations for each single agent and each group of mixed solutions by equal proportion.

[0075] Experimental method: The petri dishes were placed on the bottom of the Potter spray tower and sprayed with 1 mL of liquid. After the liquid settled for 1 minute, the dishes were removed and transferred to the rearing conditions.

[0076] Experimental replication: Each treatment should be replicated at least 4 times, and a blank control should be set up with a treatment that does not contain the reagent (including all organic solvents and emulsifiers).

[0077] Data statistics and analysis: 48 hours after treatment, check the mortality of the test insects and record the total number of mites and the number of dead mites (death criteria: use a needle tip to pluck the mite appendages; if they do not move, they are dead; if they move, they are alive).

[0078] Based on the survey data, the corrected mortality rates for each treatment were calculated.

[0079] Calculate using the following formula, and round the results to two decimal places:

[0080]

[0081] In the formula:

[0082] P – Mortality rate, expressed as a percentage (%);

[0083] K represents the number of dead insects, in heads;

[0084] N represents the total number of insects treated, in units of heads.

[0085]

[0086] In the formula:

[0087] P1 – Corrected mortality rate, in percentage (%);

[0088] P t —The mortality rate is expressed as a percentage (%).

[0089] P0 – Mortality rate in the blank control group, expressed as a percentage (%).

[0090] If the control mortality rate is <5%, no correction is needed; if the control mortality rate is between 5% and 20%, correction should be performed; if the control mortality rate is >20%, the trial needs to be repeated.

[0091] The data is processed using probability value analysis. The DPS statistical analysis system can be used to analyze the data and determine the LC of the toxicity regression line. 50 The b-value, its 95% confidence limit, and the b-value are used to evaluate the activity of the test reagent on the biological material.

[0092] The co-toxicity coefficient (CTC value) of the mixture is calculated using the following formula:

[0093]

[0094] In the formula:

[0095] ATI – Actual Measured Toxicity Index of Mixtures;

[0096] S – LC50 of standard acaricides 50 The unit is milligrams per liter (mg / L);

[0097] M – LC of the mixture 50 The unit is milligrams per liter (mg / L).

[0098] TTI = TI A *P A +TI B *P B

[0099] In the formula:

[0100] TTI – Theoretical Toxicity Index of Mixtures;

[0101] TI A —A. Toxicity index of drug A;

[0102] P A —Percentage content of drug A in the mixture, expressed as percentage (%);

[0103] TI B —Toxicity index of drug B;

[0104] P B —Percentage content of agent B in the mixture, expressed as percentage (%).

[0105]

[0106] In the formula:

[0107] CTC – Cotoxicity Coefficient;

[0108] ATI – Actual Measured Toxicity Index of Mixtures;

[0109] TTI – Theoretical Toxicity Index of Mixtures.

[0110] The co-toxicity coefficient of the compound is ≥120, which shows a synergistic effect; CTC≤80 shows an antagonistic effect; and 80<CTC<120 shows an additive effect.

[0111] Experimental results:

[0112] Tables 1 and 2 show the experimental results, indicating that pyridaben and abamectin exhibited high toxicity against Tetranychus carmine, with LC50 values... 50 The concentrations were 0.219 mg / L and 0.204 mg / L, respectively. Compound (I) showed a synergistic effect with pyridaben in the range of 1:20 to 15:1; Compound (I) showed a synergistic effect with abamectin in the range of 1:10 to 15:1.

[0113] Table 1. Determination of the combined toxicity of compound (I) with pyridaben in different ratios to Tetranychus carmine.

[0114]

[0115] Table 2. Determination of the combined toxicity of compound (I) with avermectin in different ratios against Tetranychus carmine.

[0116]

[0117] Indoor Example 2

[0118] Example references: Pesticide Indoor Bioassay Test Guidelines Part 7: Determination of Combined Effects of Mixtures NY / T1154.7-2006 and Part 13: Pesticide Indoor Bioassay Test Guidelines Insecticides Part 13: Leaf Disc Spray Method NY / T1154.13-2008.

[0119] The test insect source was the citrus paronychia mite (bred at the R&D center), with female adult mites of similar physiological condition selected from indoor rearing. Temperature: (25±1)℃; Relative humidity: 65%±5%; Photoperiod: 16 / 8h (L / D).

[0120] Preparation of test materials: Select broad bean leaves with uniform growth, make leaf discs with a punch, place a wet sponge block in the petri dish, place filter paper on it, and place leaf discs on the filter paper, with 2 leaf discs per dish. Inoculate 15 adult mites raised indoors onto the leaf discs per dish.

[0121] Drug preparation: Dissolve the drug in acetone, then dilute with 0.1% Tween-80 aqueous solution. Prepare single-dose stock solutions separately, and design the ratio according to the purpose of mixing and drug activity. Prepare five series of mass concentrations for each single agent and each group of mixed solutions by equal proportion.

[0122] Experimental method: The petri dishes were placed on the bottom of the Potter spray tower and sprayed with 1 mL of liquid. After the liquid settled for 1 minute, the dishes were removed and transferred to the rearing conditions.

[0123] Experimental replication: Each treatment should be replicated at least 4 times, and a blank control should be set up with a treatment that does not contain the reagent (including all organic solvents and emulsifiers).

[0124] Data statistics and analysis: 48 hours after treatment, check the mortality of the test insects and record the total number of mites and the number of dead mites (death criteria: use a needle tip to pluck the mite appendages; if they do not move, they are dead; if they move, they are alive).

[0125] Based on the survey data, the corrected mortality rates for each treatment were calculated.

[0126] Calculate using the following formula, and round the results to two decimal places:

[0127]

[0128] In the formula:

[0129] P – Mortality rate, expressed as a percentage (%);

[0130] K represents the number of dead insects, in heads;

[0131] N represents the total number of insects treated, in units of heads.

[0132]

[0133] In the formula:

[0134] P1 – Corrected mortality rate, in percentage (%);

[0135] P t —The mortality rate is expressed as a percentage (%).

[0136] P0 – Mortality rate in the blank control group, expressed as a percentage (%).

[0137] If the control mortality rate is <5%, no correction is needed; if the control mortality rate is between 5% and 20%, correction should be performed; if the control mortality rate is >20%, the trial needs to be repeated.

[0138] The data is processed using probability value analysis. The DPS statistical analysis system can be used to analyze the data and determine the LC of the toxicity regression line. 50 The b-value, its 95% confidence limit, and the b-value are used to evaluate the activity of the test reagent on the biological material.

[0139] The co-toxicity coefficient (CTC value) of the mixture is calculated using the following formula:

[0140]

[0141] In the formula:

[0142] ATI – Actual Measured Toxicity Index of Mixtures;

[0143] S – LC50 of standard acaricides 50 The unit is milligrams per liter (mg / L);

[0144] M – LC of the mixture 50 The unit is milligrams per liter (mg / L).

[0145] TTI = TI A *P A +TI B *P B

[0146] In the formula:

[0147] TTI – Theoretical Toxicity Index of Mixtures;

[0148] TI A —A. Toxicity index of drug A;

[0149] P A —Percentage content of drug A in the mixture, expressed as percentage (%);

[0150] TI B —Toxicity index of drug B;

[0151] P B —Percentage content of agent B in the mixture, expressed as percentage (%).

[0152]

[0153] In the formula:

[0154] CTC – Cotoxicity Coefficient;

[0155] ATI – Actual Measured Toxicity Index of Mixtures;

[0156] TTI – Theoretical Toxicity Index of Mixtures.

[0157] The co-toxicity coefficient of the compound is ≥120, which shows a synergistic effect; CTC≤80 shows an antagonistic effect; and 80<CTC<120 shows an additive effect.

[0158] Experimental results:

[0159] Table 3 shows the experimental results, indicating that avermectin exhibits high toxicity against *Paecilomyces cerevisiae*, LC50. 50 The concentration was 0.558 mg / L. Compound (I) and abamectin showed a synergistic effect in a mass ratio of 1:18 to 16:1. In particular, when the mass ratio of compound (I) to abamectin was 1:18 to 10:1, the co-toxicity coefficient (CTC) was greater than 140, indicating a significant synergistic effect.

[0160] Table 3. Determination of the combined toxicity of compound (I) with avermectin in different ratios against *Pteris vittata*.

[0161]

[0162]

[0163] Indoor Example 3

[0164] Test insect source: *Rhizoctonia solani* (bred at the R&D center), selected female adult mites kept indoors and in the same physiological state. Temperature: (25±1)℃. Relative humidity: 65%±5%, photoperiod: 16 / 8h (L / D).

[0165] Drug preparation: Dissolve the drug in acetone, then dilute with 0.1% Tween-80 aqueous solution. Prepare single-dose stock solutions separately, and design 5 formulations according to the purpose of mixing and drug activity. Prepare 5 series of mass concentrations for each single agent and each formulation mixture according to the ratio method.

[0166] Experimental method: Take a glass tube with a diameter of 1 cm, roll it evenly with 250 μL of medicine, and let the medicine dry naturally. Then, suck 15 female adult mites into the glass tube and seal it with 200 mesh gauze.

[0167] Experimental replication: Each treatment should be replicated at least 4 times, with at least 60 insects per dose treatment, and a blank control should be set up with no drugs (including all organic solvents and emulsifiers).

[0168] Data statistics and analysis: 48 hours after treatment, check the mortality of the test insects and record the total number of mites and the number of dead mites (death criteria: use a needle tip to pluck the mite appendages; if they do not move, they are dead; if they move, they are alive).

[0169] Based on the survey data, the corrected mortality rates for each treatment were calculated.

[0170] Calculate using the following formula, and round the results to two decimal places:

[0171]

[0172] In the formula:

[0173] P – Mortality rate, expressed as a percentage (%);

[0174] K represents the number of dead insects, in heads;

[0175] N represents the total number of insects treated, in units of heads.

[0176]

[0177] In the formula:

[0178] P1 – Corrected mortality rate, in percentage (%);

[0179] P t —The mortality rate is expressed as a percentage (%).

[0180] P0 – Mortality rate in the blank control group, expressed as a percentage (%).

[0181] If the control mortality rate is <5%, no correction is needed; if the control mortality rate is between 5% and 20%, correction should be performed; if the control mortality rate is >20%, the trial needs to be repeated.

[0182] The data is processed using probability value analysis. The DPS statistical analysis system can be used to analyze the data and determine the LC of the toxicity regression line. 50 The b-value, its 95% confidence limit, and the b-value are used to evaluate the activity of the test reagent on the biological material.

[0183] The co-toxicity coefficient (CTC value) of the mixture is calculated using the following formula:

[0184]

[0185] In the formula:

[0186] ATI – Actual Measured Toxicity Index of Mixtures;

[0187] S – LC50 of standard acaricides 50 The unit is milligrams per liter (mg / L);

[0188] M – LC of the mixture 50 The unit is milligrams per liter (mg / L).

[0189] TTI = TI A *P A +TI B *P B

[0190] In the formula:

[0191] TTI – Theoretical Toxicity Index of Mixtures;

[0192] TI A —A. Toxicity index of drug A;

[0193] P A —Percentage content of drug A in the mixture, expressed as percentage (%);

[0194] TI B —Toxicity index of drug B;

[0195] P B —Percentage content of agent B in the mixture, expressed as percentage (%).

[0196]

[0197] In the formula:

[0198] CTC – Cotoxicity Coefficient;

[0199] ATI – Actual Measured Toxicity Index of Mixtures;

[0200] TTI – Theoretical Toxicity Index of Mixtures.

[0201] The co-toxicity coefficient of the compound is ≥120, which shows a synergistic effect; CTC≤80 shows an antagonistic effect; and 80<CTC<120 shows an additive effect.

[0202] Experimental results:

[0203] Tables 4 and 5 show the experimental results, indicating that pyridaben and abamectin exhibited high toxicity against *Rhizoctonia solani*, with LC50 values... 50The concentrations were 9.7744 mg / L and 1.0479 mg / L, respectively. Compound (I) showed a synergistic effect with pyridaben in the range of 1:25 to 15:1; Compound (I) also showed a synergistic effect with abamectin in the range of 1:25 to 30:1.

[0204] Table 4. Determination of the combined toxicity of compound (I) with pyridaben against *Rhizoctonia solani* at different ratios.

[0205]

[0206] Table 5. Determination of the combined toxicity of compound (I) and avermectin in different ratios against root mite *Strombus spicata*.

[0207]

[0208] Field Example 1

[0209] Field efficacy trial for controlling citrus red spider mites

[0210] Test crop: Citrus (Wogan);

[0211] Test subject: Citrus red spider mite;

[0212] Experimental design: 8% Compound (I)·pyridaben EC (5:3) and 8% Compound (I)·avermectin EC (5.5:2.5) were used as treatments. 20% Compound (I) SC, 15% pyridaben EC, and 1.8% abamectin EC were used as controls. A water control was also included. A total of 6 treatments were administered, with 3 replicates. There were 18 plots, with 2 trees per plot, arranged in a randomized block design, with each plot separated by a row of trees.

[0213] Table 6. Test reagents and dosages

[0214]

[0215] Experimental site: Citrus orchard in Shuangqiao Town, Wuming District, Nanning City, Guangxi Zhuang Autonomous Region. The citrus trees in the experimental area are growing at a relatively uniform rate, and citrus red spider mite infestations have been severe in recent years. The soil fertility of the experimental site is high, and the cultivation and management conditions are good, with trees planted there year-round.

[0216] The pesticide was applied on October 28, 2022. The day of application was sunny with a high of 30°C and a low of 19°C. There was a level 1 northeasterly wind. The weather during the trial period was mostly cloudy.

[0217] Application method, timing, and frequency: Use a motorized sprayer (WL-ABSC type) and manual spraying to ensure even spraying across the entire tree. Based on actual field conditions and farmers' water usage habits, determine the water usage per citrus tree to be 1.8L. The amount of pesticide applied should be such that the leaves are evenly covered with pesticide and a few drops drip down. Apply once.

[0218] Survey Method: Randomly select one point from each citrus tree along the east, west, south, north, and center directions. Mark one branch at each point and record the total number of live citrus red spider mites on the leaves of the marked branch (starting from the top leaves, with a minimum of 5 leaves). The survey primarily focuses on adult mites and nymphs (which can be observed with a magnifying glass). Surveys are conducted before application of the pesticide and again 3 and 10 days after application.

[0219] Method for calculating drug efficacy: Drug efficacy is calculated using the following formula:

[0220]

[0221] During the experiment, the citrus trees in each experimental plot grew well, and no pesticide damage was observed in any of the treatments.

[0222] As shown in Table 7, the mixture of compound (I) with pyridaben and abamectin has a good control effect on red spider mites on citrus trees, showing good rapid effect. Three days after application, the control efficacy of 8% compound (I)·pyridaben EC (5:3) and 8% compound (I)·abamectin EC (5.5:2.5) were 95.23% and 94.44%, respectively. At the 0.05 level, through difference analysis, the mixture of compound (I) with pyridaben and abamectin was significantly higher than the control single agent 20% compound (I) suspension, 15% pyridaben EC, and 1.8% abamectin EC.

[0223] Table 7. Control efficacy of different treatments for citrus red spider mite 3 days after application.

[0224]

[0225] Note: The efficacy (%) in the table is the average of each replicate, with the difference at the 0.05% level. The same applies to the following tables.

[0226] As shown in Table 8, with the passage of time, the combination of compound (I) with pyridaben and abamectin has increased efficacy and prolonged duration of action against red spider mites on citrus trees. Ten days after application, the control efficacy of 8% compound (I)·pyridaben EC (5:3) and 8% compound (I)·abamectin EC (5.5:2.5) were 97.85% and 98.49%, respectively. At the 0.05 level, through differential analysis, the mixture of compound (I) with pyridaben and abamectin was significantly higher than the control single-agent formulations of 20% compound (I) suspension, 15% pyridaben EC, and 1.8% abamectin EC.

[0227] Table 8. Control efficacy of different treatments against citrus red spider mites 10 days after application.

[0228]

[0229] Note: Same as above.

[0230] Through indoor toxicity testing and field trials on citrus fruits, the acaricidal composition of formula (I) described in this invention, combined with either pyridaben or abamectin, showed good control efficacy against phytophagous mites. The acaricidal composition or formulation obtained by this invention exhibits significant efficacy, superior to single-agent formulations in delaying the development of resistance and prolonging pesticide retention. Furthermore, no phytotoxicity was observed in the experiments, indicating that the enhanced synergistic effect of the acaricidal composition or formulation reduces production and usage costs while ensuring crop safety.

[0231] Field Example 2

[0232] Test crop: garlic, variety: Jinxiang white garlic;

[0233] Test subject: *Spodoptera litura*;

[0234] Experimental location: Jinxiang, Jining City, Shandong Province. The experimental field is flat, the previous crop was soybean, the soil is sandy loam, and the fertility is moderate.

[0235] Test reagents:

[0236] Table 9. Experimental Treatments and Drug Dosage

[0237] Test treatment test reagents Dosage (mL / kg seeds) 1 8% Formula (I) Compound·Dyridaben Emulsifiable Concentrate (5:3) 0.2 2 8% Formula (I) compound · abamectin emulsifiable concentrate (5.5:2.5) 0.2 3 15% Pyridaben Emulsifiable Concentrate 0.3 4 1.8% Avermectin EC 0.5 5 6% Imidacloprid Suspension Seed Coating 8 6 Water treatment (CK) /

[0238] Experimental Design: The experiment included 5 seed treatments with pesticides and 1 water treatment (CK), arranged randomly with 3 replicates per treatment. The plot area was 20m². 2 Before seed treatment, dilute the pesticide with 100mL of water. Seed treatment was conducted on October 4, 2021. Select garlic cloves harvested that year that are approximately 5g each, firm and plump, white in color, free of disease spots and wounds, and uniform in size. After treatment, dry the cloves and sow them the next day at a planting density of 600,000 plants / hm². 2 .

[0239] Investigation method: The damage caused by *Rhizoctonia solani* was investigated on November 22, 2021, during the peak period of *Rhizoctonia solani* infestation. Fifteen plants were randomly sampled from each treatment to investigate the *Rhizoctonia solani* infestation on diseased plants (investigation method for *Rhizoctonia solani*: the total number of mites on pseudostems and bulbs was investigated by combining aboveground observation with indoor microscopic examination after seedling removal).

[0240] During the harvest period, the incidence rate of diseased plants in each plot was investigated. Fifty plants were randomly selected from each treatment, and the number of diseased plants, incidence rate, and control effect were recorded.

[0241] Drug efficacy calculation method: Drug efficacy is calculated according to the following formula:

[0242]

[0243] During the experiment, garlic growth was observed to be good in all treatment plots, and no phytotoxicity was observed in any treatment.

[0244] Experimental results:

[0245] The control effects of each treatment on garlic root mite are shown in Table 10. The number of root mites, the incidence rate and the disease index of each treatment were lower than those of the control. The control efficacy of 8% compound (I)·pyridaben EC (5:3) and 8% compound (I)·avermectin EC (5.5:2.5) were 88.38% and 89.34%, respectively.

[0246] Table 10. Control effects of different treatments on garlic root mite.

[0247]

[0248] Note: The efficacy (%) in the table above is the average of each replicate. Lowercase letters indicate significant differences at the 5% level.

[0249] According to field surveys, no adverse reactions to the pesticides were observed in the leaves of any of the treatments, indicating that the treatments were safe for garlic growth at the concentrations used in the experiment.

[0250] Furthermore, no phytotoxicity was found in the compound pesticides during the experiment, indicating that the improved synergistic effect of the obtained acaricide composition or formulation can reduce production and usage costs and ensure crop safety.

[0251] Although the present invention has been described in detail above with general description and specific embodiments, some modifications or improvements can be made to it based on the present invention, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention are within the scope of protection claimed by the present invention.

Claims

1. A miticidal composition characterized in that: The acaricidal composition comprises active ingredient A and active ingredient B, wherein the active ingredient A is a compound of formula (I): (I), the active ingredient B is abamectin, and the mass ratio of the compound of formula (I) to abamectin is 1:25-30:

1.

2. The acaricidal composition according to claim 1, characterized by The mass ratio of the compound of formula (I) to abamectin is 1:25, 1:18, 1:12, 1:10, 1:7, 1:4, 5:1, 3:2, 3:1, 6:1, 15:2, 10:1, 15:1, 16:1, 30:

1.

3. The acaricidal composition according to claim 1, characterized by The content of the active ingredient A and the active ingredient B in the acaricidal composition is 2-80 wt% based on the total weight of the acaricidal composition.

4. The acaricidal composition according to claim 1, characterized by The acaricidal composition comprises, in addition to the active ingredients, an agriculturally acceptable auxiliary ingredient selected from one or more of wetting agents, dispersants, emulsifiers, thickening agents, disintegrating agents, antifreezing agents, antifoaming agents, solvents, preservatives, stabilizers, synergists or carriers.

5. The acaricidal composition according to claim 4, characterized by The acaricidal composition can be prepared into an agriculturally permissible formulation form selected from solid formulations and / or liquid formulations.

6. The acaricidal composition according to claim 5, characterized by The solid formulation is selected from wettable powder, water dispersible granule, soluble granule; the liquid formulation is selected from soluble liquid, emulsifiable concentrate, water emulsion, suspension, suspoemulsion, microemulsion, dispersible oil suspension.

7. Use of a miticidal composition according to any one of claims 1 to 6 for the control of harmful mites, characterized in that, The harmful mites are Rhizoglyphus echinopus, Olpidium brassicae, Tetranychus cinnabarinus, Tetranychus urticae, Tetranychus truncatus.

8. Use according to claim 7, characterized in that, The acaricidal composition is applied to the harmful mites and / or the medium where the harmful mites grow in need of control in an effective dose.

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