A spirocyclic derivative and a pharmaceutical composition comprising the same

Abstract

This invention belongs to the field of acaricide technology and discloses an acaricide composition containing propargite and its application. The acaricide composition of this invention comprises active ingredient A and active ingredient B, wherein active ingredient A is a compound of formula I, and active ingredient B is propargite, and the mass ratio of active ingredient A to active ingredient B is 1:50 to 42:1. The acaricide composition of this invention exhibits a significant synergistic effect against common plant mites while simultaneously reducing crop phytotoxicity.

Description

Technical Field

[0001] This invention belongs to the field of pesticide acaricide technology, and relates to an acaricide composition containing propargite and its application. Background Technology

[0002] Agricultural mites are a significant pest and a major obstacle to agricultural production. The improper use of insecticides and acaricides has made mites one of the most difficult pests to control in agricultural production.

[0003] Propyleneone, also known as acaricide, is a highly effective, low-toxicity, broad-spectrum, and long-lasting organosulfur acaricide that effectively controls mite damage. It boasts advantages such as good control efficacy, low cost, and low likelihood of developing resistance. Currently, it is a commonly used pesticide in mite control. However, when used during the spring shoot and tender leaf stage, the relatively high dosage applied by farmers can easily cause phytotoxicity to tender shoots, leaves, flowers, and young fruits of citrus and other fruit varieties, affecting tree vigor and, in severe cases, yield.

[0004] Because there are currently few effective acaricides, and many have different names for the same pesticide, coupled with the common practice among some fruit growers of using the same pesticide they believe to be most effective, repeated application leads to mites developing resistance to some pesticides, making control increasingly ineffective. In an attempt to achieve better control, some fruit growers arbitrarily increase the concentration or dosage of pesticides, further accelerating the development of mite resistance. Furthermore, the use of some pesticides at high concentrations can easily cause phytotoxicity. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of the present invention is to provide an acaricide composition containing propargite. The acaricide composition of the present invention has a significant synergistic effect on common plant mites, and reduces phytotoxicity to crops and reduces the amount of pesticide used.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a mite-killing composition containing propargite, wherein the mite-killing composition comprises active ingredient A and active ingredient B, wherein active ingredient A is a compound of formula I: The active ingredient B is propargite;

[0007] Furthermore, the mass ratio of active ingredient A to active ingredient B is 1:42 to 35:1;

[0008] Furthermore, the mass ratio of active ingredient A to active ingredient B is 1:35 to 30:1;

[0009] Furthermore, the total weight of the acaricide combination group is 100 wt%, and the total weight of active ingredient A and active ingredient B accounts for 1% to 80% of the total weight of the acaricide composition.

[0010] Furthermore, in addition to the active ingredient, the acaricide composition also contains pesticide-permitted 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.

[0011] Further, the wetting agent is selected from one or more of alkylbenzene sulfonates, alkylnaphthalene sulfonates, lignin sulfonates, sodium dodecyl sulfate, sodium dioctyl succinate sulfonate, α-olefin sulfonates, alkylphenol polyoxyethylene ethers, castor oil polyoxyethylene ethers, alkylphenol ethoxylates, fatty alcohol ethoxylates, 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

[0012] The dispersant is selected from one or more of the following: lignin sulfonates, alkyl naphthalene sulfonates formaldehyde condensates, naphthalene sulfonates, tristyrylphenol ethoxylate phosphates, 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

[0013] The emulsifier is selected from one or more of the following: calcium dodecylbenzenesulfonate, alkylphenol formaldehyde resin polyoxyethylene ether, phenethylphenol polyoxyethylene polyoxypropylene ether, fatty alcohol ethylene oxide-propylene oxide copolymer, styrene-phenol polyoxyethylene ether, castor oil polyoxyethylene ether, and alkylphenol ether phosphate; and / or

[0014] 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

[0015] 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

[0016] Antifreeze is selected from one or more of alcohols, alcohol ethers, chlorinated hydrocarbons, and inorganic salts; and / or

[0017] 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

[0018] The solvent is selected from one or more of benzene, toluene, xylene, mesitylene, methanol, ethanol, isopropanol, n-butanol, dimethyl sulfoxide, dimethylformamide, cyclohexanone, hydrocarbon carbonates, diesel oil, solvent oil, vegetable oil, vegetable oil derivatives, and water; and / or

[0019] The preservative is selected from one or more of propionic acid, sodium propionate, sorbic acid, sodium sorbate, potassium sorbate, benzoic acid, sodium benzoate, sodium p-hydroxybenzoate, methyl p-hydroxybenzoate, Kathon, and 1,2-benzisothiazolin-3-one; and / or

[0020] 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

[0021] Synergists are selected from synergistic phosphorus, synergistic ether; and / or

[0022] 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.

[0023] Furthermore, the acaricidal composition can be prepared into any formulation permitted by pesticides, wherein the formulation is a solid or liquid formulation;

[0024] 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.

[0025] 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.

[0026] Furthermore, the formulation is an emulsifiable concentrate, microemulsion, water emulsion, wettable powder, or water-dispersible granule.

[0027] The present invention also discloses the use of the acaricidal composition described above for the control of plant mites.

[0028] Furthermore, the plant mites mentioned are spider mites or gall mites.

[0029] Furthermore, the spider mite pests mentioned are two-spotted spider mite, carmine spider mite, citrus spider mite, citrus spider mite, six-spotted spider mite, citrus split spider mite, or truncate spider mite, and the gall mite pests mentioned are citrus rust mite and wolfberry gall mite.

[0030] The beneficial effects of this invention are as follows:

[0031] 1. This invention rationally combines acaricides with different mechanisms of action, resulting in excellent control effects against various plant mites and a significant synergistic effect;

[0032] 2. The acaricide composition of the present invention reduces phytotoxicity to crops, is safe for plants and non-target organisms, reduces the dosage of the agent, and reduces agricultural production costs. Detailed Implementation

[0033] 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.

[0034] Formulation preparation example:

[0035] Preparation Example 1: 55% Compound I of Propylthiazoline Emulsifiable Oil (1:10)

[0036] Formula: 5% Formula I compound, 50% propargite, 10% DMF, 3% succinate sulfonate, 12% phenethylphenol polyoxyethylene ether, 3% alkylphenol polyoxyethylene ether, xylene to make up the balance;

[0037] Preparation method: The measured active ingredients, solvent, and co-solvent are added to a mixing tank and stirred to dissolve them. Then, the emulsifier is added, and the remaining solvent is used to make up the balance. The mixture is stirred evenly in a mixing tank and filtered to obtain the emulsifiable oil required by this invention.

[0038] Preparation Example 2: 27% Formula I compound·propyrithione microemulsion (1:8)

[0039] Formula: 3% Formula I compound, 24% propargite, 12% cyclohexanone, 10% styrylphenol polyoxyethylene ether, 2% alkylphenol polyoxyethylene ether phosphate, 3% calcium dodecylbenzene sulfonate, 2% sodium fatty alcohol polyoxyethylene ether sulfate, 0.1% silicone defoamer, 4% ethylene glycol, 0.5% glycerin, 0.1% xanthan gum, 0.1% Kathon, deionized water to make up the balance;

[0040] Preparation method: According to the formulation ratio in the example, the active ingredients, solvent, emulsifier, etc. are mixed evenly to obtain the oil phase, the antifreeze is mixed evenly with water to obtain the aqueous phase, the oil phase is added to the aqueous phase under stirring and stirred evenly, and shearing is continued for 10 minutes. Then, defoamer and other ingredients are added and stirred evenly to obtain small droplets with oil phase particles of 0.01 to 0.1 micrometers, which is the microemulsion product.

[0041] Preparation Example 3: 26% Compound I·Propylthiazoline Water Emulsion (12:1)

[0042] Formula: 24% Formula I compound, 2% propargite, 1% isotridecyl alcohol polyoxyethylene ether, 1% styrene-phenol polyoxyethylene ether, 6% EO-PO block copolymer, 20% cyclohexanone, 0.15% xanthan gum, 5% glycerol, 0.1% sodium benzoate, 0.1% silicone oil, deionized water to make up the balance;

[0043] Preparation method: According to the formulation ratio in the preparation 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 to form a well-dispersed water emulsion product.

[0044] Preparation Example 4: 30% Formula I compound·propyrithione wettable powder (5:1)

[0045] Formula: 25% Formula I compound, 5% propargite, 2% sodium dodecyl sulfate, 10% calcium lignosulfonate, 5% naphthalene sulfonate, 15% silica, and kaolin to make up the balance;

[0046] Preparation method: The active ingredients, dispersant, wetting agent and filler are mixed according to the formula ratio, stirred evenly in a stirring tank, and then pulverized and mixed evenly multiple times by an air jet mill to prepare the wettable powder of the composition of the present invention.

[0047] Indoor bioactivity assay

[0048] Example 1: Indoor activity test of the compound composition against two-spotted spider mite and citrus paronychia.

[0049] Test basis: The test was conducted in accordance with NY / T 1154.12-2008 "Guidelines for the determination of biological activity of pesticides in the laboratory - Insecticides - Part 12: Tetranychus slide immersion method".

[0050] Experimental targets: Two-spotted spider mite (Tetranychus urticae Koch) and citrus psyllid mite (Panonychuscitri Mcgregor).

[0051] Test reagents: Formula I compound technical grade, propargite technical grade.

[0052] Experimental steps:

[0053] 1) Preparation of test materials: Select female adult mites that are kept indoors and have the same physiological state.

[0054] Cut double-sided tape into 2cm lengths and attach them to one end of a glass slide. Then, select healthy female adult mites and attach their backs to the double-sided tape (avoiding the legs, antennae, and mouthparts). Place 30 mites per slide and put them in a container lined with a damp sponge. Cover the container and place it at (25±1)℃. After 2 hours, examine the slide under a microscope, remove any dead, injured, or inactive individuals, and replenish the slide to 30 mites.

[0055] 2) Preparation of the drug: Prepare a stock solution by using an organic solvent, and then prepare five series of mass concentrations by using a 0.1% Tween-80 aqueous solution in equal proportions.

[0056] 3) Chemical treatment: Immerse the glass slide in the chemical solution and gently shake for 5 seconds. Remove the slide, absorb the excess chemical solution with absorbent paper, place it in a white porcelain dish with a damp sponge, and cover it with a transparent plastic film.

[0057] Each treatment was repeated four times, with a blank control consisting of a treatment without any reagents (containing all organic solvents and emulsifiers).

[0058] 4) Feeding and observation

[0059] The containers containing the treated test insects were placed in a temperature of (25±1)℃ and a photoperiod of L:D=(16:8)h for rearing and observation.

[0060] 5) Inspection: Check the mortality of the test insects 48 hours after treatment, and record the total number of insects and the number of dead insects.

[0061] Data statistics and analysis:

[0062] Based on the survey data, the corrected mortality rates for each treatment were calculated using the following formula, and the results were rounded to two decimal places.

[0063]

[0064] In the formula:

[0065] P – Mortality rate, expressed as a percentage (%);

[0066] K represents the number of dead insects, in heads;

[0067] N represents the total number of insects treated, in units of heads.

[0068]

[0069] In the formula:

[0070] P1 – Corrected mortality rate, in percentage (%);

[0071] P t —The mortality rate is expressed as a percentage (%).

[0072] P0 – Mortality rate in the blank control group, expressed as a percentage (%).

[0073] 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 according to the corrected mortality rate formula; if the control mortality rate is >20%, the trial needs to be repeated.

[0074] The DPS statistical analysis system was used to analyze the data and obtain the virulence regression equation, correlation coefficient, and LC. 50 The value is used to evaluate the activity of the test reagent on the biological sample.

[0075] The co-toxicity coefficient (CTC value) of the mixture is calculated using the following formula:

[0076]

[0077] In the formula:

[0078] ATI – Actual Measured Toxicity Index of Mixtures;

[0079] S – LC50 of standard acaricides 50 The unit is milligrams per liter (mg / L);

[0080] M – LC of the mixture 50 The unit is milligrams per liter (mg / L).

[0081] TTI = TI A ×P A +TI B ×P B

[0082] In the formula:

[0083] TTI – Theoretical Toxicity Index of Mixtures;

[0084] TI A —A. Toxicity index of drug A;

[0085] P A —Percentage content of drug A in the mixture, expressed as percentage (%);

[0086] TI B —Toxicity index of drug B;

[0087] P B —Percentage content of agent B in the mixture, expressed as percentage (%).

[0088]

[0089] In the formula:

[0090] CTC – Cotoxicity Coefficient;

[0091] ATI – Actual Measured Toxicity Index of Mixtures;

[0092] TTI – Theoretical Toxicity Index of Mixtures.

[0093] 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.

[0094] The results of the indoor tests are shown in Tables 1 and 2:

[0095] Table 1. Indoor bioactivity test of compound I with propargite-specific combination on Tetranychus tinctoria.

[0096] Test reagents <![CDATA[LC 50 (mg / L)]]> (ATI) (TTI) Cotoxicity coefficient (CTC) Formula I compound 4.8471 100.000 / / propargite 317.664 1.526 / / 1:50 102.693 4.720 3.457 136.545 1:42 77.6799 6.240 3.816 163.520 1:24 51.9578 9.329 5.465 170.708 1:12 26.4226 18.345 9.101 201.571 1:6 16.0011 30.292 15.594 194.261 10:1 2.9312 165.362 91.048 181.621 20:1 3.0713 157.819 95.311 165.584 30:1 3.1947 151.723 96.823 156.701 35:1 3.4992 138.520 97.265 142.416 42:1 3.9938 121.366 97.710 124.210

[0097] Table 1 shows that compound I exhibits high toxicity against Tetranychus bisporus and has good control efficacy against the mite. Compound I and propargite did not show a synergistic effect against Tetranychus bisporus in the ratio range of 1:50–42:1, but their co-toxicity coefficient was greater than 130 in the same range, indicating a significant synergistic effect.

[0098] Table 2 shows the indoor bioactivity test of compound I with propargite-specific combination against *Pseudomonas citrus*.

[0099] Test reagents <![CDATA[LC 50 (mg / L)]]> (ATI) (TTI) Cotoxicity coefficient (CTC) Formula I compound 3.1125 100.000 / / propargite 355.2489 0.876 / / 1:35 54.8772 5.672 3.630 156.264 1:20 34.3443 9.063 5.596 161.939 1:10 17.0796 18.223 9.887 184.310 10:1 1.9815 157.078 90.989 172.635 20:1 2.0266 153.582 95.280 161.191 30:1 2.3923 130.105 96.802 134.402

[0100] As can be seen from Table 2, compound I exhibits high toxicity to *Pseudomonas citrinum*, and the combined effect of compound I and propargite on *Pseudomonas citrinum* in the range of 1:35 to 30:1 shows a synergistic effect.

[0101] Field efficacy trials

[0102] Example 2: Field efficacy test of compound composition for controlling cotton red spider mites

[0103] Experimental basis: The experiment was conducted in accordance with GB / T 17980.74-2004 "Guidelines for Field Efficacy Tests of Pesticides (II) Part 74: Control of Red Spider Mites in Cotton with Insecticides".

[0104] Experimental crop: Cotton (Luyan Cotton No. 15).

[0105] Test subject: cotton red spider mite.

[0106] Test reagents: 55% compound I propargite emulsifiable concentrate (1:10), 27% compound I propargite microemulsion (1:8), 30% compound I propargite wettable powder (5:1), 57% propargite emulsifiable concentrate, and 20% compound I aqueous emulsion.

[0107] Experimental site: The experimental site is Bairen Village, Yiyang Township, Feicheng City, Shandong Province. The soil in the experimental site is sandy loam with moderate soil fertility.

[0108] Plot arrangement: The experimental agent, control agent, and blank control were arranged in a randomized block design, with a 0.5m protection row surrounding each experimental plot and the experimental field. The area of ​​each experimental plot was 25m². 2 Each treatment was repeated 4 times.

[0109] Application time and frequency: On June 10, 2020, a single application of pesticide was performed using conventional spraying. A Gongnong-16 backpack sprayer was used to spray the entire cotton plant, ensuring even coverage of both the upper and lower surfaces of the leaves. The application occurred at the early stage of cotton red spider mite infestation. No other pesticides were used during the experiment.

[0110] Survey Method: For each plot, 30 leaves were labeled on each plant for surveying. The mite population before treatment was no less than 500. The baseline population was surveyed before treatment, and the number of live mites was surveyed at 1 day, 3 days, and 7 days after treatment. The number of live and nymphal mites on the labeled 30 leaves was counted, and the mite population reduction rate and control effect were calculated.

[0111] Safety survey: After application of pesticides, the growth of cotton in each plot will be investigated periodically to observe for any abnormal phenomena.

[0112] Methods for calculating drug efficacy:

[0113]

[0114]

[0115] Table 3. Results of field efficacy trials of the compound composition for controlling cotton red spider mites.

[0116]

[0117] As shown in the table above, the acaricidal composition of the present invention has a good control effect on cotton spider mites. Three days after application, the acaricidal composition of the present invention has a control efficacy of more than 80%, showing good rapid action compared to the control single agent; 14 days after application, the control efficacies of 55% Compound I·Propylene EC (1:10), 27% Compound I·Propylene Microemulsion (1:8), and 30% Compound I·Propylene WP (5:1) against cotton spider mites were 97.45%, 94.19%, and 91.02%, respectively.

[0118] Example 3: Investigation on the control efficacy of the compound composition against citrus spider mites

[0119] This experiment was conducted in accordance with the People's Republic of China National Standard "Guidelines for Field Efficacy Tests of Pesticides (I) Acaricides for the Control of Citrus Paronychia".

[0120] Experimental target: Citrus spider mite.

[0121] Experimental Site: The experiment was conducted in a citrus orchard in Dingshu Town, Yixing City, Jiangsu Province. The soil at the experimental site was yellow clay soil with medium to high fertility. The soil type, fertility, organic matter content, fertilizer and water management, and cultivation practices of the experimental orchards were basically the same. No acaricides or insecticides were applied to the experimental orchard in the 30 days prior to the experiment.

[0122] Experimental crop: Citrus (Red Beauty).

[0123] Test reagents: 55% compound I propargite emulsifiable concentrate (1:10), 27% compound I propargite microemulsion (1:8), 30% compound I propargite wettable powder (5:1), 57% propargite emulsifiable concentrate, and 20% compound I aqueous emulsion.

[0124] Experimental design: The experimental plot area was 2 citrus trees, and the experimental plots were arranged in a randomized block design, with each treatment replicated 4 times.

[0125] Experimental method: The experiment was conducted on June 14, 2021. The pesticide was applied by spraying. The spraying equipment was a backpack automatic adjustable electric sprayer. During the application, the front and back of the leaves were sprayed evenly until the pesticide was about to drip.

[0126] Efficacy survey: A fixed-point survey method was used. The initial insect population was surveyed before application, and surveys were conducted again at 3, 7, and 14 days after application. Two fruit trees were surveyed in each plot. On each tree, tender shoots were marked in five directions (east, west, south, north, and center) for fixed-point surveys. Five leaves were surveyed in each direction, and the number of live mites on both sides of the leaves was counted. A total of 50 leaves were surveyed in each plot to count the number of live mites.

[0127] Methods for calculating drug efficacy:

[0128]

[0129]

[0130] Direct effects on crops: Observations during the experiment showed that the above-mentioned agents had no adverse effects on the growth of citrus leaves, branches, and fruits, and no phytotoxicity was observed. This indicates that the tested agents were safe for citrus at the dosages used in this experiment.

[0131] Table 4. Results of the investigation on the control efficacy of the compound composition against citrus spider mites.

[0132]

[0133]

[0134] As can be seen from the test results in the table above, the reasonable combination of compound I and propargite can effectively control the damage caused by spider mites. The acaricide composition of the present invention has a significant effect compared with the control single agent, with good rapid effect and long duration of action.

[0135] Example 4: Safety test of the compound composition on citrus

[0136] Experimental crop: Citrus (Wenzhou mandarin orange).

[0137] Experimental location: The experiment was conducted in a citrus orchard in Yuanqiao Town, Huangyan District, Taizhou City, Zhejiang Province. The experimental crop was 5-year-old citrus trees, and the trees in the experimental site were of moderate vigor.

[0138] Test reagents: 55% compound I·propargyl emulsifiable concentrate (1:10), 27% compound I·propargyl microemulsion (1:8), 57% propargyl emulsifiable concentrate, and 20% compound I aqueous emulsion.

[0139] Experimental setup: The experimental, control, and blank control treatments were arranged in a randomized block design. Each experimental plot consisted of two citrus trees, with a protective row around it. Each treatment was replicated four times.

[0140] Application and Survey Time: The experiment was conducted during the spring shoot stage of citrus, at an air temperature of 25℃. An equal volume of water was sprayed as a blank control. A Gongnong-16 backpack sprayer was used for application, ensuring even coverage on both sides of the leaves, with the solution suspended but not dripping. Phytotoxicity on citrus shoots was assessed 3 and 14 days after application; leaf damage was assessed 30 days after application, and the degree of leaf damage was graded.

[0141] Survey method: Two citrus trees were surveyed in each plot. During the survey, tender shoots were marked in five directions (east, south, west, north, and center) on each tree. Leaves on one tender shoot were surveyed in each direction. A total of 10 tender shoots were surveyed for each treatment. The number of leaves on the tender shoots was recorded, the number of leaves at each level was counted, and the leaf color, branch color, and leaf thickness of each treatment were compared.

[0142] The severity of harm is classified as follows:

[0143] Grade 0: Leaves are not damaged;

[0144] Grade 1: The area of ​​damaged spots on the leaves is less than 1 / 4 of the leaf area;

[0145] Grade 2: The affected area accounts for 1 / 4 to 1 / 2 of the leaf area;

[0146] Level 3: The affected area covers 1 / 2 to 3 / 4 of the leaf area;

[0147] Level 4: The affected area covers more than 3 / 4 of the leaf area.

[0148] Key Point Classification Table

[0149] Calculate the leaf damage index using the following formula:

[0150]

[0151] The test results are shown in the table below:

[0152] Table 5. Results of safety tests on citrus fruits using the compound composition.

[0153]

[0154] As shown in the safety test results above, the use of 57% propargite EC during the spring shoot and tender leaf stage causes phytotoxicity to the tender leaves. The symptoms are circular or irregular yellowish-brown marks on the back of the tender leaves, uneven leaf surface, and when the damage is severe, the tender leaves become wrinkled and brittle. However, the acaricide composition of the present invention is safe for citrus.

[0155] The results of indoor toxicity tests and field efficacy tests show that combining compound I with propargite in an appropriate ratio can significantly improve efficacy, effectively control crop mites, and ensure safety for the tested crops.

[0156] It should be understood that the above embodiments are merely some embodiments of the present invention, provided only to better understand the embodiments of the present invention, and are not all embodiments of the present invention. In practical applications, by adjusting the content of each component and the composition of the components in the present invention, different and numerous embodiments can be obtained, all of which are within the scope of the present invention.

Claims

1. A spirodiclofen-containing acaricidal composition, characterized by, The acaricidal composition comprises active ingredient A and active ingredient B, the active ingredient A is a compound of formula I: (formula I), the active ingredient B is propargite, and the mass ratio of the active ingredient A to the active ingredient B is 1:42~35:

1.

2. The acaricidal composition according to claim 1, characterized by The mass ratio of the active ingredient A to the active ingredient B is 1:35-30:

1.

3. The acaricidal composition according to claim 1, characterized by The mass ratio of the active ingredient A to the active ingredient B is 1:42, 1:24, 1:12, 1:6, 10:1, 20:1, 30:1, or 35:

1.

4. The acaricidal composition according to claim 1, characterized by The total weight of the acaricidal combination composition is 100 wt%, and the total weight of the active ingredient A and the active ingredient B accounts for 1-80% of the total weight of the acaricidal composition.

5. The acaricidal composition according to claim 1, characterized by The acaricidal composition contains, in addition to the active ingredients, one or more of the following agriculturally acceptable auxiliary ingredients: wetting agents, dispersants, emulsifiers, thickening agents, disintegrating agents, antifreezing agents, antifoaming agents, solvents, preservatives, stabilizers, synergists, or carriers.

6. The acaricidal composition according to claim 1, characterized by The acaricidal composition can be prepared into any one of the following formulations: emulsifiable concentrate, microemulsion, aqueous emulsion, wettable powder, or water dispersible granule.

7. Use of the acaricidal composition according to any one of claims 1-6 for controlling plant acarid pests.

8. Use according to claim 7, characterized in that, The plant acarid pests are Tetranychidae acarid pests, and the Tetranychidae acarid pests are Tetranychus urticae and Panonychus citri.

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