A binary insecticide for preventing and treating aphids of rape and its preparation method and application

Abstract

The application belongs to the technical field of pesticide compounding and agricultural pest control, and specifically discloses a binary insecticide for preventing and treating rape aphids, a preparation method and application thereof. The binary insecticide comprises 1-51% of an active component by mass percentage, and the balance is a pesticide-acceptable auxiliary agent and carrier. The active component comprises thiamethoxam and quercetin. The binary insecticide for preventing and treating rape aphids and the preparation method and application thereof can be prepared into eight types of formulations, including water dispersible granules, wettable powders, suspensions, emulsifiable concentrates, microemulsions, water emulsions, microcapsule suspensions and seed treatment suspensions. The binary insecticide can delay aphid resistance, reduce the use amount of chemical pesticides, and is suitable for preventing and controlling the whole growth period of rape. The seed treatment formulation can reduce the toxicity to non-target organisms such as bees, and is suitable for green prevention and control of aphids such as Myzus persicae in rape fields.

Description

Technical Field

[0001] This invention relates to the field of pesticide compounding and agricultural pest control technology, and in particular to a binary insecticide for controlling rapeseed aphids, its preparation method and application. Background Technology

[0002] rape( Brassica napus Rapeseed (L.) is one of my country's most important oilseed crops, widely planted in the Yangtze River basin, southwest China, and south China's winter rapeseed areas. Its yield and quality are directly related to my country's edible oil supply security. Aphids are the most serious pests in rapeseed production, with the peach aphid (L.) being the dominant species in my country's fields. Myzus persica Radish aphid ( Lipaphis very hot ) and cabbage aphid ( Brassica oleracea There are three types. Aphids feed in clusters on the tender leaves, heart leaves, flower buds, and stems of rapeseed using their piercing-sucking mouthparts, causing leaf curling and yellowing, stunted plant growth, flower and bud drop, and poor pod development. In years with a general outbreak, rapeseed yield can be reduced by more than 10%, and in years with a severe outbreak, yield can be reduced by more than 30%, resulting in a complete crop failure. In addition, aphids are also vectors for various rapeseed viral diseases such as turnip mosaic virus and cucumber mosaic virus, and the indirect losses caused by virus transmission far outweigh the direct damage from feeding.

[0003] Chemical control of rapeseed aphids still relies primarily on single-agent pesticides, commonly including neonicotinoids (imidacloprid, thiamethoxam, acetamiprid), pyrethroids, and organophosphates. Due to aphids' extremely high reproductive rate (10-20 generations per year), large population size, and strong adaptability, long-term, high-volume, and frequent use of single-mechanism insecticides has led to varying degrees of resistance in field aphid populations to many commonly used pesticides, resulting in a continuous decline in control efficacy and an increase in pesticide dosage. Furthermore, single-agent pesticides also suffer from narrow control spectrum, short residual effect, high cost, and high toxicity to non-target organisms such as bees. Pesticide formulation is an effective technical approach to delay pest resistance, improve control efficacy, broaden the control spectrum, and reduce pesticide costs. Scientifically mixing insecticides with different mechanisms of action can achieve synergistic effects, reduce the dosage of single agents, and lower pesticide residues and environmental risks.

[0004] In existing technologies, compound pesticides for rapeseed aphid control mostly combine two chemical pesticides, such as acetamiprid and pymetrozine, which can improve both rapid and sustained efficacy. However, long-term use still carries the risk of resistance evolution, and the total amount of chemical pesticides used is not significantly reduced. Furthermore, quercetin is a natural flavonoid polyphenol compound widely found in plants, and its antioxidant and anti-inflammatory activities have been confirmed in the pharmaceutical and food industries. Agricultural research shows that quercetin can strongly inhibit insect acetylcholinesterase (AChE) activity, interfering with aphid feeding behavior, and has the advantages of being naturally low in toxicity, easily degradable, and environmentally compatible. However, quercetin alone has weak insecticidal activity and cannot meet the needs of aphid control in large-scale fields. Therefore, reducing the use of chemical pesticides, improving environmental safety, and developing compound formulations, especially seed treatment formulations, are of significant practical importance for the green and sustainable control of rapeseed aphids. Summary of the Invention

[0005] The purpose of this invention is to provide a binary insecticide for controlling rapeseed aphids, its preparation method and application, which can delay aphid resistance and reduce the amount of chemical pesticides used. The seed treatment formulation can reduce toxicity to non-target organisms such as bees, and is suitable for green control of aphids such as peach aphids in rapeseed fields.

[0006] To achieve the above objectives, the present invention provides a binary insecticide for controlling rapeseed aphids, comprising an active ingredient with a mass percentage of 1% to 51%, and the remainder being pesticide-acceptable adjuvants and carriers. The active ingredients include thiamethoxam and quercetin.

[0007] Preferably, the formulation is one of water-dispersible granules, wettable powders, suspension concentrates, emulsifiable concentrates, microemulsions, water-in-oil emulsions, microcapsule suspensions, and seed treatment suspensions.

[0008] Preferably, the mass ratio of thiamethoxam to quercetin is 1:50 to 50:1.

[0009] Preferably, the mass ratio of thiamethoxam to quercetin is one of 1:10, 20:1, or 50:1.

[0010] Preferably, the additive is one or more of the following: wetting agent, dispersant, disintegrant, binder, thickener, stabilizer, antifreeze, preservative, emulsifier, film-forming agent, suspending agent, and defoamer; The carrier is one or more of the following: silica, kaolin, urea, water, xylene, methyl oleate, and pyrrolidone.

[0011] A method for preparing a binary insecticide for controlling rapeseed aphids, wherein when the formulation is a water-dispersible granule, the carrier, wetting agent, dispersant, disintegrant, thiamethoxam and quercetin are mixed and ultra-finely pulverized, then mixed and kneaded with an aqueous solution containing a binder, and then extruded, granulated, dried and sieved to obtain the finished product. When the dosage form is a wettable powder, thiamethoxam, quercetin, adjuvants, and fillers are mixed evenly and then pulverized by air jet milling to obtain the finished product; When the formulation is a suspension or seed treatment suspension, thiamethoxam, quercetin, and adjuvants are mixed, and the pH value is adjusted after sand milling to obtain the finished product. When the dosage form is an emulsifiable concentrate, thiamethoxam, quercetin, adjuvants, and fillers are stirred and mixed evenly to obtain the finished product; When the dosage form is a microemulsion or water-in-oil emulsion, thiamethoxam and quercetin are dissolved with adjuvants to obtain an oil phase, and the oil phase is mixed with the water phase and stirred and homogenized to obtain the finished product; When the dosage form is a microcapsule suspension, thiamethoxam, quercetin and adjuvants are first mixed and milled to obtain a suspension. Then, melamine-formaldehyde prepolymer is prepared. After mixing the melamine-formaldehyde prepolymer with the suspension, the pH is adjusted to carry out the coating reaction. After neutralization, the finished product is obtained. When the formulation is a seed treatment suspension, thiamethoxam, quercetin, penetrant T, sodium naphthalenesulfonate formaldehyde condensate, polyvinyl alcohol, xanthan gum, magnesium aluminum silicate, organosilicon defoamer, ethylene glycol, sodium benzoate, and water are mixed, sand-milled, and the pH is adjusted to neutral 7.0 to obtain the finished product.

[0012] Preferably, when the formulation is a seed treatment suspension, the raw material composition by mass percentage is as follows: Thiamethoxam 20%, quercetin 1%, penetrant T 2%, sodium naphthalenesulfonate formaldehyde condensate 4%, polyvinyl alcohol 4%, xanthan gum 0.1%, magnesium aluminum silicate 1%, organosilicon defoamer 0.3%, ethylene glycol 4%, sodium benzoate 0.2%, water to 100%; When the dosage form is a microemulsion, the raw material composition by mass percentage is as follows: Thiamethoxam 30%, quercetin 3%, xylene 8%, n-butanol 5%, agricultural emulsion 2020 4%, EPE emulsifier 16%, glycerol 4%, water to make up to 100%.

[0013] Application of a binary insecticide for controlling rapeseed aphids.

[0014] Preferably, the rapeseed aphid includes one or more of the following: peach aphid, turnip aphid, and cabbage aphid.

[0015] Preferably, the prevention and control measures include foliar spraying and seed coating / mixing, wherein foliar spraying specifically includes: The binary insecticide is diluted and sprayed evenly on both sides of rapeseed leaves. It is suitable for emergency control of aphids during the seedling, bolting, and flowering stages. Seed coating involves coating seeds with a seed treatment suspension at an appropriate ratio of pesticide to seed. After sowing, the seed coating can continue to exert a systemic insecticidal effect during the seedling stage, reducing the number of foliar sprays during the growing season and lowering the risk of exposure to non-target organisms such as bees during the rapeseed flowering period.

[0016] Therefore, the present invention employs the above-mentioned binary insecticide for controlling rapeseed aphids, its preparation method, and its application, with the following beneficial effects: (1) Dual-target synergistic effect with significant enhancement. This invention utilizes thiamethoxam to competitively bind to insect nicotinic acetylcholine receptors (nAChR), blocking nerve signal transmission; quercetin strongly inhibits acetylcholinesterase (AChE) activity, resulting in a large accumulation of acetylcholine in the synaptic cleft. The mechanisms of action of the two are completely different, and when combined, they achieve dual nerve blockade, producing a synergistic effect. Indoor toxicity tests show that the co-toxicity coefficient (CTC) of all ratios is greater than 120, reaching the level of enhancement; the CTC exceeds 400 in the optimal ratio, and the CTC is as high as 633.22 in the 50:1 ratio, with a very significant enhancement effect, which can greatly reduce the field dosage of the active ingredient.

[0017] (2) Delaying the development of pesticide resistance in pests and extending the lifespan of pesticides. This invention utilizes a combination of two active ingredients with different mechanisms of action, which can reduce the selective pressure of aphids against a single pesticide, reduce the evolution rate of resistant populations, extend the field lifespan of pesticides, and alleviate the current industry dilemma of aphid resistance intensifying.

[0018] (3) Excellent control effect, with both rapid and sustained efficacy. Field trials showed that when 33% thiamethoxam·quercetin microemulsion was diluted 2000 times and sprayed, the average control efficacy reached 96.67% 3 days after application and 99.48% 7 days after application, which was significantly better than thiamethoxam single agent at the same dosage (60.83% control efficacy 3 days after application and 83.34% control efficacy 7 days after application). Both rapid and sustained efficacy were greatly improved, which can quickly control the outbreak of aphids.

[0019] (4) Good environmental compatibility, reducing ecological risks. The quercetin of this invention is a natural plant-derived flavonoid compound that is easily degraded, has low residue, and is highly safe for non-target organisms. When compounded, it can significantly reduce the amount of chemical pesticide thiamethoxam, reducing pesticide residues and environmental pollution. In particular, the seed treatment suspension formulation exerts its efficacy through systemic absorption after seed dressing, which can reduce foliar spraying during flowering, significantly reducing the toxicity risk to pollinating insects such as bees, and is suitable for the green production needs of rapeseed.

[0020] (5) Diverse formulations suitable for control throughout the entire growth period. This invention provides eight commercial formulations that can meet the application needs of rapeseed at different growth stages, such as seed dressing, seedling spraying, bolting control, and emergency control during flowering, and support integrated pest management strategies in different scenarios.

[0021] (6) Pest and disease control, improving overall yield. The composition of the present invention can effectively control the population of aphids while cutting off the vector route for aphids to transmit turnip mosaic virus and cucumber mosaic virus, reducing the occurrence of rapeseed viral diseases, achieving the comprehensive effect of "pest and disease control", and further ensuring rapeseed yield and quality.

[0022] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the synergistic effect mechanism of the binary insecticide in an embodiment of the present invention. Detailed Implementation

[0024] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0025] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0026] Thiamethoxam is a second-generation neonicotinoid insecticide that acts on nicotinic acetylcholine receptors (nAChR) in the insect's central nervous system. It exhibits excellent systemic conductivity, allowing it to be translocated acrophysically to newly formed plant tissues, making it highly effective against piercing-sucking pests. However, long-term use of thiamethoxam alone has led to increased aphid resistance, and foliar spraying during flowering poses safety risks to pollinating insects such as bees. Furthermore, quercetin exhibits relatively weak insecticidal activity when used alone.

[0027] like Figure 1 As shown, the synergistic mechanism of all embodiments of the present invention is as follows: through the binary insecticide of thiamethoxam and quercetin, thiamethoxam competitively inhibits insect nAChR, and quercetin strongly inhibits acetylcholinesterase (AChE) activity, resulting in a large accumulation of the neurotransmitter acetylcholine (ACh), thus doubly blocking the nerve signal transmission of aphids, causing aphids to become disoriented, paralyzed and die, achieving synergistic effect, and the insecticidal effect is significantly better than that of thiamethoxam or quercetin alone.

[0028] Example 1 Indoor toxicity determination of the binary combination of thiamethoxam and quercetin, with the following test materials: Test reagents: 98% thiamethoxam technical grade, 97% quercetin technical grade. The specific structure of the compound quercetin is as follows: ; Test insects: rapeseed peach aphid ( Myzus persica The nymphs were collected in a rapeseed field in a certain region in 2017. They were raised indoors at a constant temperature for multiple generations, and healthy and active nymphs of uniform size were selected for testing.

[0029] The test method was performed according to the leaf immersion method of the agricultural industry standard NY / T 1154.14-2008 "Guidelines for Indoor Bioassay Tests of Pesticides - Insecticides", as detailed below: Preparation of stock solutions: The two technical materials were prepared into 2% stock solutions using dimethylformamide (DMF), and then diluted with an aqueous solution containing 0.01% Tween 80 to prepare a series of single-agent and compound solutions (100, 10, 1 mg / L). The ratio of the compound drug solution was set as follows: thiamethoxam (A) : quercetin (B) in a mass ratio of 1:50, 1:20, 1:10, 1:5, 1:2, 1:1, 2:1, 5:1, 10:1, 20:1, and 50:1, a total of 11 ratios. Each ratio was set with 5 to 7 gradient concentrations. Each concentration was replicated 3 times, and each replicate was inoculated with at least 30 peach aphid nymphs. Culture conditions: After treatment, the insects were placed in an artificial climate chamber with a temperature of 25±1℃, a relative humidity of 60%±10%, and a photoperiod of 14L:10D. The number of dead insects was checked and recorded after 24 hours.

[0030] The data statistics and evaluation methods are as follows: The slope of the toxicity regression line b±SE and LC were calculated using Probit software. 50 Values ​​and 95% confidence intervals were used to calculate the co-toxicity coefficient (CTC) to evaluate the type of combined effect: CTC≥120 indicates synergistic effect, 80<CTC<120 indicates additive effect, and CTC≤80 indicates antagonistic effect. The relevant index calculation equations (1)~(4) are shown below: (1) (2) (3) (4) The toxicity test results of thiamethoxam and quercetin alone and in various compound ratios against peach aphids are shown in Table 1.

[0031] Table 1. Lethal median concentration and co-toxicity coefficient of the binary combination of thiamethoxam and quercetin against peach aphids.

[0032] Table 1 shows that both thiamethoxam and quercetin have insecticidal activity against peach aphids, with thiamethoxam showing significantly higher toxicity than quercetin alone. All compound formulations exhibited a synergistic effect with a co-toxicity coefficient greater than 120. The co-toxicity coefficients of the A:B ratios of 1:10, 20:1, and 50:1 all exceeded 400, demonstrating a highly significant synergistic effect. The 50:1 ratio showed the highest co-toxicity coefficient and the best synergistic effect.

[0033] Example 2 To verify the synergistic effect of quercetin on thiamethoxam, four treatments were set up: thiamethoxam alone, thiamethoxam + 0.01% quercetin, thiamethoxam + 0.02% quercetin, and thiamethoxam + 0.05% quercetin. The median lethal concentration (LC50) of quercetin against peach aphids collected from rapeseed fields in a certain region in 2026 was determined. 50 90% lethal concentration LC 90 The synergistic effect ratio was calculated, and the results are shown in Table 2. At the same time, the mortality rate of different concentrations of quercetin treated alone was determined, and the results are shown in Table 3.

[0034] Table 2. Determination of the synergistic effect of quercetin on thiamethoxam

[0035] Table 3 Mortality rates of quercetin treatment alone

[0036] As shown in Tables 2 and 3, trace amounts of quercetin can significantly enhance the insecticidal activity of thiamethoxam, and the synergistic effect increases dramatically with increasing quercetin concentration. 0.05% quercetin can increase the toxicity of thiamethoxam by more than 140 times, confirming that the two have a strong synergistic effect potential. A small amount of quercetin can significantly reduce the amount of chemical pesticides used.

[0037] Example 3 A binary insecticide for controlling rapeseed aphids, specifically 51% thiamethoxam·quercetin water-dispersible granules, formulated by weight percentage: Thiamethoxam 50%, quercetin 1%, sodium dodecylbenzenesulfonate (wetting agent) 4%, sodium naphthalenesulfonate formaldehyde condensate (dispersant) 2%, lignin sulfonate (dispersant) 2%, urea (disintegrant) 2%, polyethylene glycol-6000 (binder) 2%, and silica (carrier) to make up to 100%.

[0038] The preparation method is as follows: Weigh all powder raw materials, including carrier, wetting agent, dispersant, disintegrant, and active ingredient, according to the formula ratio, mix them evenly, and then perform ultrafine grinding. Dissolve polyethylene glycol-6000 in a measured amount of water beforehand, and add it together with the ultrafine ground powder to a kneader to knead thoroughly to make a plastic material. Feed the material into an extrusion granulator for granulation, and after drying and sieving, obtain 51% thiamethoxam·quercetin water-dispersible granules.

[0039] Example 4 A binary insecticide for controlling rapeseed aphids, specifically a 21% thiamethoxam·quercetin wettable powder formulation, with the following formula by weight percentage: Thiamethoxam 20%, quercetin 1%, sodium dodecyl sulfonate (wetting agent) 3%, naphthalene sulfonate formaldehyde condensate (dispersant) 5%, potassium phosphate (auxiliary agent) 2%, silica (carrier) 10%, kaolin (carrier) to make up to 100%.

[0040] The preparation method is as follows: Weigh all raw materials, including carrier, wetting agent, dispersant, adjuvant, and technical grade, according to the formula ratio. After premixing evenly, pass the mixture into an air jet mill and adjust the working pressure for ultrafine grinding. After grinding, sieve to obtain 21% thiamethoxam·quercetin wettable powder.

[0041] Example 5 A binary insecticide for controlling rapeseed aphids, specifically a 51% thiamethoxam·quercetin suspension, formulated by weight percentage as follows: thiamethoxam 50%, quercetin 1%, sodium dodecyl sulfate (wetting agent) 1%, sodium naphthalenesulfonate formaldehyde condensate (dispersant) 3%, xanthan gum (thickening agent) 0.1%, bentonite (stabilizer) 5%, ethylene glycol (antifreeze agent) 4%, sodium benzoate (preservative) 0.1%, water to 100%.

[0042] The preparation method is as follows: Weigh out the active ingredient, wetting agent, dispersant, thickener, stabilizer, antifreeze, preservative and water according to the formula, add them to a sand mill, and sand mill at 2000 r / min for 3 hours. After sand milling, filter to obtain 51% thiamethoxam·quercetin suspension.

[0043] Example 6 A binary insecticide for controlling rapeseed aphids, specifically a 21% thiamethoxam·quercetin emulsifiable concentrate, formulated by weight percentage as follows: 20% thiamethoxam, 1% quercetin, 10% xylene (solvent), 5% pyrrolidone (solvent), 5% sodium dodecylbenzenesulfonate (emulsifier), 4% By-15 (emulsifier), 2% OP-20 (emulsifier), 5% epoxidized soybean oil (stabilizer), and methyl oleate (solvent) to make up to 100%.

[0044] The preparation method is as follows: According to the formula, the active ingredient, emulsifier, solvent and stabilizer are added into the mixing vessel in sequence and stirred until completely dissolved and mixed evenly to obtain 21% thiamethoxam·quercetin emulsifiable concentrate.

[0045] Example 7 A binary insecticide for controlling rapeseed aphids, specifically a 33% thiamethoxam·quercetin microemulsion, formulated by weight percentage as follows: thiamethoxam 30%, quercetin 3%, xylene 8%, n-butanol 5%, agricultural emulsion 2020 (emulsifier) ​​4%, EPE (agricultural emulsion 33, emulsifier) ​​16%, glycerol (antifreeze agent) 4%, water to 100%.

[0046] The preparation method is as follows: An aqueous phase was prepared by uniformly mixing emulsifier, n-butanol, glycerol and water; an oil phase was prepared by dissolving thiamethoxam and quercetin technical in xylene; the oil phase was slowly added to the aqueous phase under high-speed stirring, and stirring was continued until the system became transparent, thus obtaining a 33% thiamethoxam·quercetin microemulsion.

[0047] Example 8 A binary insecticide for controlling rapeseed aphids, specifically a 21% thiamethoxam·quercetin water-in-oil emulsion, formulated by weight percentage as follows: 20% thiamethoxam, 1% quercetin, 10% xylene, 4% agricultural emulsion 500 (emulsifier), 2% Span-80 (emulsifier), 2% agricultural emulsion 2201 (emulsifier), 4% glycerol (antifreeze agent), and water to 100%.

[0048] The preparation method is as follows: The active ingredient was dissolved in xylene to prepare an oil phase; an emulsifier, glycerol and water were mixed to prepare an aqueous phase; the oil phase was added to the aqueous phase under high-speed stirring, and after homogenization and emulsification, a 21% thiamethoxam·quercetin aqueous emulsion was obtained.

[0049] Example 9 A binary insecticide for controlling rapeseed aphids, specifically a 51% thiamethoxam·quercetin microcapsule suspension, formulated by weight percentage as follows: thiamethoxam 50%, quercetin 1%, formaldehyde solution 6.7%, melamine 3.3%, ammonium chloride 1%, penetrant T (chemical name diisooctyl maleate sulfonate, wetting agent) 2%, sodium naphthalenesulfonate formaldehyde condensate (dispersant) 4%, xanthan gum (thickener) 0.1%, bentonite (stabilizer) 3%, ethylene glycol (antifreeze agent) 4%, sodium benzoate (preservative) 0.1%, water to 100%.

[0050] The preparation method is as follows: S1. Weigh the raw material, wetting agent, dispersant, thickener, stabilizer, antifreeze, preservative and water according to the formula, add them to a sand mill and sand mill at 2000 r / min for 3 hours to obtain a suspension for later use. S2. Weigh melamine and formaldehyde solution, and react them in a water bath at 70°C with stirring to obtain melamine-formaldehyde prepolymer; S3. Pour the melamine-formaldehyde prepolymer obtained in S2 into the suspension obtained in S1, stir evenly, adjust the pH to 4.2, and react for 1.5 h; add 25% ammonium chloride solution, and continue to react for 0.5 h; finally adjust the pH to 7.0 to obtain 51% thiamethoxam·quercetin microcapsule suspension.

[0051] Example 10 A binary insecticide for controlling rapeseed aphids, specifically a 21% thiamethoxam·quercetin seed treatment suspension, formulated by weight percentage as follows: 20% thiamethoxam, 1% quercetin, 2% penetrant T (wetting agent), 4% sodium naphthalenesulfonate formaldehyde condensate (dispersant), 4% polyvinyl alcohol (film-forming agent), 0.1% xanthan gum (thickener), 1% magnesium aluminum silicate (suspending agent), 0.3% organosilicon (defoamer), 4% ethylene glycol (antifreeze agent), 0.2% sodium benzoate (preservative), and water to 100%.

[0052] Preparation method: Weigh the above raw materials according to the formula, add them to a sand mill and mill at 2000 r / min for 5 h. After milling, adjust the pH to 7.0, defoam and filter to obtain 21% thiamethoxam·quercetin seed treatment suspension. This formulation has good film-forming properties, is not easy to fall off after coating, and can control aphids in the seed stage for a long time through systemic translocation.

[0053] Example 11 A field efficacy trial for controlling rapeseed aphids was conducted. The trial site was a winter rapeseed field in a certain region. Water and fertilizer conditions were uniform in the experimental field, and the peach aphid infestation was severe. No other insecticides were applied during the trial. Test agents: 33% thiamethoxam·quercetin microemulsion (the binary insecticide of Example 7), 30% thiamethoxam microemulsion (control single agent), and a water blank control. The specific experimental design is as follows: Each treatment was set up with 4 replicates, randomly arranged in blocks, with each block area being 50m². 2 The test reagent was diluted 2000 times, and administered at a rate of 1:667m³. 2 (mu) 45kg of water was used to spray the rapeseed leaves evenly on both sides using an electric sprayer. Before the pesticide was applied, the insect population was investigated. A five-point sampling method was used to investigate the number of aphids on 10 rapeseed leaves at each point. The number of surviving aphids was investigated 3 days and 7 days after the pesticide was applied. The insect population reduction rate and control effect were calculated. Equations (5) to (6) are shown below: (5) (6) The field control effects of each treatment on the rapeseed peach aphid are shown in Table 4.

[0054] Table 4. Field control efficacy of pesticides against rapeseed peach aphid

[0055] Table 4 shows that the aphid population in the blank control area exhibited a natural increasing trend, with a negative population decline rate. The 33% thiamethoxam·quercetin microemulsion of this invention achieved an average control efficacy of 96.67% 3 days after application and 99.48% 7 days after application, significantly superior to the control efficacy of 30% thiamethoxam alone. This confirms that the combination of the two agents has a significant synergistic effect in the field, effectively controlling rapeseed aphid damage with excellent residual efficacy.

[0056] Therefore, the present invention employs the above-mentioned binary insecticide for controlling rapeseed aphids, its preparation method, and its application. It can be prepared into eight formulations: water-dispersible granules, wettable powders, suspension concentrates, emulsifiable concentrates, microemulsions, water-in-oil emulsions, microcapsule suspensions, and seed treatment suspensions. These formulations delay aphid resistance, reduce the amount of chemical pesticides used, and are suitable for control throughout the entire growth period of rapeseed. The seed treatment formulations can reduce toxicity to non-target organisms such as bees, making them suitable for green control of aphids such as peach aphids in rapeseed fields.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A binary insecticide for controlling rapeseed aphids, characterized in that: It includes active ingredients with a mass percentage of 1% to 51%, with the remainder being pesticide-acceptable adjuvants and carriers; The active ingredients include thiamethoxam and quercetin.

2. The binary insecticide for controlling rapeseed aphids according to claim 1, characterized in that: The formulation is one of the following: water-dispersible granules, wettable powders, suspension concentrates, emulsifiable concentrates, microemulsions, water-in-oil emulsions, microcapsule suspensions, and seed treatment suspensions.

3. The binary insecticide for controlling rapeseed aphids according to claim 1, characterized in that: The mass ratio of thiamethoxam to quercetin is 1:50 to 50:

1.

4. The binary insecticide for controlling rapeseed aphids according to claim 3, characterized in that: The mass ratio of thiamethoxam to quercetin is one of 1:10, 20:1, or 50:

1.

5. A binary insecticide for controlling rapeseed aphids according to claim 1, characterized in that: The additives are one or more of the following: wetting agents, dispersants, disintegrants, binders, thickeners, stabilizers, antifreeze agents, preservatives, emulsifiers, film-forming agents, suspending agents, defoamers, and water. The carrier is one or more of the following: silica, kaolin, urea, water, xylene, methyl oleate, and pyrrolidone.

6. A method for preparing a binary insecticide for controlling rapeseed aphids as described in any one of claims 1 to 5, characterized in that: When the dosage form is water-dispersible granules, the carrier, wetting agent, dispersant, disintegrant, thiamethoxam, and quercetin are mixed and ultra-finely pulverized, then mixed and kneaded with an aqueous solution containing a binder, and then extruded, granulated, dried, and sieved to obtain the finished product. When the dosage form is a wettable powder, thiamethoxam, quercetin, adjuvants, and fillers are mixed evenly and then pulverized by air jet milling to obtain the finished product; When the formulation is a suspension or seed treatment suspension, thiamethoxam, quercetin, and adjuvants are mixed, and the pH value is adjusted after sand milling to obtain the finished product. When the dosage form is an emulsifiable concentrate, thiamethoxam, quercetin, adjuvants, and fillers are stirred and mixed evenly to obtain the finished product; When the dosage form is a microemulsion or water emulsion, thiamethoxam and quercetin are dissolved with adjuvants to obtain an oil phase, and the oil phase is mixed with the water phase and stirred and homogenized to obtain the finished product; When the dosage form is a microcapsule suspension, thiamethoxam, quercetin and adjuvants are first mixed and milled to obtain a suspension. Then, melamine-formaldehyde prepolymer is prepared. After mixing the melamine-formaldehyde prepolymer with the suspension, the pH is adjusted to carry out the coating reaction. After neutralization, the finished product is obtained. When the formulation is a seed treatment suspension, thiamethoxam, quercetin, penetrant T, sodium naphthalene sulfonate formaldehyde condensate, polyvinyl alcohol, xanthan gum, magnesium aluminum silicate, organosilicon defoamer, ethylene glycol, sodium benzoate, and water are mixed, sand-milled, and the pH is adjusted to neutral to obtain the finished product.

7. The method for preparing a binary insecticide for controlling rapeseed aphids according to claim 6, characterized in that: When the formulation is a seed treatment suspension, the raw material composition by mass percentage is: Thiamethoxam 20%, quercetin 1%, penetrant T 2%, sodium naphthalenesulfonate formaldehyde condensate 4%, polyvinyl alcohol 4%, xanthan gum 0.1%, magnesium aluminum silicate 1%, organosilicon defoamer 0.3%, ethylene glycol 4%, sodium benzoate 0.2%, water to 100%; When the dosage form is a microemulsion, the raw material composition by mass percentage is as follows: Thiamethoxam 30%, quercetin 3%, xylene 8%, n-butanol 5%, agricultural emulsion 2020 4%, EPE emulsifier 16%, glycerol 4%, water to make up to 100%.

8. The application of a binary insecticide for controlling rapeseed aphids as described in any one of claims 1 to 5 in the control of rapeseed aphids.

9. The application according to claim 8, characterized in that: The rapeseed aphids include one or more of the following: peach aphid, turnip aphid, and cabbage aphid.

10. The application according to claim 8, characterized in that: The prevention and control measures include foliar spraying and seed coating / mixing.

Images