A suspension containing pyriproxyfen and clothianidin and use thereof

Abstract

The application provides a suspension agent containing pyriproxyfen and clothianidin, which comprises pyriproxyfen 3-8%, clothianidin 30-40%, clove extract 1-1.5%, and astragalus polysaccharide 0.5-1% according to percentage by weight; and the weight ratio of the clove extract and the astragalus polysaccharide is 3:2. The suspension agent provided by the application has good wetting property, strong soil permeability, can improve the effective utilization rate of the liquid medicine, and improves the drug efficacy.

Description

Technical Field

[0001] This invention belongs to the field of insecticides, specifically relating to a suspension containing pyriproxyfen and thiamethoxam and its application. Background Technology

[0002] Pyriproxyfen is a phenyl ether insect growth regulator, a novel insecticide belonging to the juvenile hormone analogue class. It is characterized by low toxicity, long-lasting effect, safety for crops and fish, and minimal impact on the ecological environment. It has good control effects on whiteflies, scale insects, diamondback moths, beet armyworms, cotton bollworms, pear psyllids, and thrips, and also provides excellent control of flies, mosquitoes, and other sanitary pests.

[0003] Thiamethoxam is a novel neonicotinoid insecticide with a thiazole ring, created and developed by Sumitomo Chemical Takeda Pesticides in Japan. It mainly acts on the central nervous system of insects and has systemic, stomach poison, and contact effects. It is highly effective against hemiptera, thrips, lepidopteran, beetle, and dipteran pests in crops such as rice, orchards, and vegetables.

[0004] The leek maggot, commonly known as the leek maggot, belongs to the genus *Mammillaria* of the family Myctomidae in the suborder Diptera. It is widely distributed in Northeast, North, Central, and Northwest China. This insect can damage leeks, onions, garlic, melons, lettuce, flowers, and medicinal herbs. The larvae primarily bore into the roots and stems of leeks, causing damage. In general, the infestation rate is 20%–30% in most fields, but can reach 100% in severe cases, resulting in yield losses of 30%–80%, often leading to crop failure or replanting.

[0005] Clove, an evergreen tree belonging to the genus Syzygium in the family Myrtaceae, has extracts containing various components, such as eugenol, semi-terpenoids, flavonoids, tannins, organic acids, and polysaccharides. Currently, it is primarily used in the medical field, exhibiting antibacterial, anti-inflammatory, antiviral, anti-ulcer, analgesic, and antidiarrheal effects. In agriculture, research indicates that clove extract can be used as an insecticide, fungicide, and plant growth regulator.

[0006] Astragalus polysaccharides are water-soluble heteropolysaccharides extracted from the dried roots of the legume Astragalus membranaceus. They possess complex structures and diverse biological activities, and are widely used in research and applications in areas such as immune regulation, metabolic control, tissue repair, and anti-tumor activity. In agriculture, they can be used for sterilization, promoting plant growth, and as synergists. Chinese patent CN120694257A discloses an agricultural synergist containing astragalus polysaccharides, which can be used to prepare insecticides for controlling two-spotted spider mites. This patented technology modifies the astragalus polysaccharides, altering their conformation, and works synergistically with other components in the synergist to improve the rapid action and duration of effect of the acaricide.

[0007] Chinese patent CN101796957A discloses a pyriproxyfen compound insecticide, wherein the active ingredient of the insecticide includes pyriproxyfen and at least one chloronicotinamide insecticide, wherein the weight ratio of pyriproxyfen to chloronicotinamide insecticide is 40:1 to 1:40, and the chloronicotinamide insecticide includes thiamethoxam. This insecticide can be used to control citrus scale insects, cucumber whiteflies, and rice planthoppers. Shanghai Shengnong Biochemical Products Co., Ltd. has registered a 40% pyriproxyfen·thiamethoxam suspension concentrate for the control of leek maggots.

[0008] The primary method for controlling leek maggots is root drenching. However, conventional pyriproxyfen·thiamethoxam suspension formulations exhibit high resistance to particle movement within soil pores, making them easily adsorbed by soil colloids and organic matter. Furthermore, the strong hydrophobicity of pyriproxyfen further exacerbates pesticide retention on the soil surface, ultimately resulting in poor pesticide deposition in the root zone. Additionally, conventional pyriproxyfen·thiamethoxam suspension formulations have poor permeability and wettability, while soil colloids strongly compete for adsorption of suspended particles, leading to poor spreading ability of the pesticide on the surface of leek bulbs and roots, low adhesion, and easy runoff. All of these issues reduce the effective utilization rate of the pesticide solution, severely impacting its efficacy. Summary of the Invention

[0009] Based on the above, the purpose of this invention is to provide a suspension containing pyriproxyfen and thiamethoxam. This suspension has good wettability and strong soil permeability, which can improve the effective utilization rate of the pesticide solution. The technical solution of this invention is as follows: A suspension containing pyriproxyfen and thiamethoxam, wherein, by weight percentage, the suspension comprises 3-8% pyriproxyfen, 30-40% thiamethoxam, 1-1.5% clove extract, and 0.5-1% astragalus polysaccharide.

[0010] Preferably, the suspending agent comprises, by weight percentage, 5.1% pyriproxyfen, 34.9% thiamethoxam, 1-1.5% clove extract, and 0.5-1% astragalus polysaccharide.

[0011] More preferably, the weight ratio of clove extract to astragalus polysaccharide is 3:2.

[0012] Preferably, the suspending agent further includes one or more of the following: dispersant, wetting agent, thickener, antifreeze agent, preservative, and solvent.

[0013] The suspension is used to control leek maggots.

[0014] The beneficial effects of this invention are: 1. The suspension agent provided by this invention has strong permeability, which can increase the penetration depth of the drug solution in the soil.

[0015] 2. The suspension agent provided by the present invention has good wettability, which can improve the adhesion of the drug solution to the roots and bulbs.

[0016] 3. The suspending agent provided by the present invention can improve the effective utilization rate of the drug solution, thereby improving the efficacy. Detailed Implementation

[0017] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to specific embodiments. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Unless otherwise specified, the experimental methods used in the following examples are conventional methods.

[0019] Unless otherwise specified, all raw materials and reagents used in the following examples are commercially available.

[0020] The clove extract described in this invention was purchased from Shanxi Haoying Biotechnology Co., Ltd.; the astragalus polysaccharide was purchased from Shaanxi Tengmai Biotechnology Co., Ltd.

[0021] I. Formulation Examples Example 1 Pyriproxypyr, 5.1%; Thiamethoxam, 34.9%; Clove extract, 1.2%; Astragalus polysaccharide, 0.8%; Naphthalenesulfonate formaldehyde condensate, 2.5%; Fatty alcohol polyoxyethylene ether, 1%; Xanthan gum, 0.15%; Ethylene glycol, 4%; Kathon, 0.1%; Add deionized water to bring the level up to 100%.

[0022] Example 2 Pyriproxypyr, 5.1%; Thiamethoxam, 34.9%; Clove extract, 1.5%; Astragalus polysaccharide, 1%; Naphthalenesulfonate formaldehyde condensate, 2.5%; Fatty alcohol polyoxyethylene ether, 1%; Xanthan gum, 0.15%; Ethylene glycol, 4%; Kathon, 0.1%; Add deionized water to bring the level up to 100%.

[0023] Comparative Example 1 Pyriproxypyr, 5.1%; Thiamethoxam, 34.9%; Naphthalenesulfonate formaldehyde condensate, 2.5%; Fatty alcohol polyoxyethylene ether, 1%; Xanthan gum, 0.15%; Ethylene glycol, 4%; Kathon, 0.1%; Add deionized water to bring the level up to 100%.

[0024] Comparative Example 2 Pyriproxypyr, 5.1%; Thiamethoxam, 34.9%; Clove extract, 1.6%; Astragalus polysaccharide, 0.4%; Naphthalenesulfonate formaldehyde condensate, 2.5%; Fatty alcohol polyoxyethylene ether, 1%; Xanthan gum, 0.15%; Ethylene glycol, 4%; Kathon, 0.1%; Add deionized water to bring the level up to 100%.

[0025] Comparative Example 3 Pyriproxypyr, 5.1%; Thiamethoxam, 34.9%; Clove extract, 0.4%; Astragalus polysaccharide, 1.6%; Naphthalenesulfonate formaldehyde condensate, 2.5%; Fatty alcohol polyoxyethylene ether, 1%; Xanthan gum, 0.15%; Ethylene glycol, 4%; Kathon, 0.1%; Add deionized water to bring the level up to 100%.

[0026] II. Surface Tension Measurement Test Test reagents: Example 1, Comparative Example 1, Comparative Example 2, Comparative Example 3.

[0027] Experimental Design: The reagents for each treatment were diluted and set aside. Surface tension was measured using a fully automated interfacial tensiometer. Each treatment was repeated four times, with water as a control. The specific design is shown in the table below: Table 1 Experimental Design

[0028] The experimental results are shown in the table below. Adding clove extract and astragalus polysaccharide reduced the surface tension of the medicinal solution. When the ratio of the two was 3:2, the surface tension reached 28.29 mN / m, lower than that of the comparative treatments. This reduction in surface tension improves the wetting, spreading, and adhesion of the medicinal solution on the surface of leek roots and bulbs, thereby increasing the effective utilization rate of the solution.

[0029] Table 2 Surface tension measurement data

[0030] The above test results show that the suspension solution containing pyriproxyfen and thiamethoxam provided by the present invention has low surface tension, which can improve the wetting, spreading and adhesion ability of the solution on the surface of leek roots and bulbs, thereby improving the effective utilization rate of the solution.

[0031] III. Soil Infiltration Depth Measurement Test Test reagents: Example 1, Comparative Example 1, Comparative Example 2, Comparative Example 3.

[0032] Experimental Design: Sterilized sandy loam soil was layered into an acrylic glass column, 5 cm thick, and gently compacted to a total height of 20 cm, ensuring uniform soil density. Water was slowly poured into the column from the top until water droplets seeped out from the bottom, and the column was allowed to stand for 24 hours. Each test reagent was diluted 10,000 times and prepared for use. 10 ml of the test solution was slowly added dropwise to the top of the soil column using a pipette. The column was then placed in a well-ventilated, room-temperature environment and allowed to stand for 24 hours before testing. Each treatment was repeated four times.

[0033] Starting from the top of the soil column, samples were taken every 1 cm using a sampler. The soil samples were placed in centrifuge tubes, 10 ml of acetonitrile was added, and the mixture was vortexed for 10 min before centrifugation. The supernatant was filtered through a 0.22 μm micromembrane, and the content of active ingredients was determined by HPLC. The detection standard was ≥0.01 μg / g soil of active ingredients. The detection of active ingredients at each depth was recorded, and the average depth of effective ingredient migration for each treatment group was calculated.

[0034] The experimental results are shown in the table below. Adding clove extract and astragalus polysaccharide increased the depth of the active ingredients in the herbal solution. When the ratio of the two was 3:2, the average depths of pyriproxyfen and thiamethoxam reached 12.3 cm and 12.8 cm, respectively, which were higher than those of the comparative treatments. Increased depth of active ingredient deposition allows the herbal solution to cover the common depth of leek maggots, thus improving the effective utilization rate of the herbal solution.

[0035] Table 3 Soil infiltration depth measurement data

[0036] The above experimental results show that the suspension containing pyriproxyfen and thiamethoxam provided by this invention has strong penetrability and a large depth of penetration, which can cover the depth where leek maggots usually occur, thereby improving the efficacy.

[0037] IV. Field efficacy trials Test reagent: Example 1, 40% pyriproxyfen·thiamethoxam SC (PD20253057).

[0038] The tested crop was 791 leek.

[0039] Test location: Shouguang City, Shandong Province.

[0040] Experimental Design: Fields with uniform leek growth were selected for the experiment. Three treatment groups were set up, with each plot measuring 20m². 2 Each treatment was repeated 4 times, as shown in the table below: Table 4 Field Trial Design

[0041] At the initial stage of leek maggot infestation, apply pesticide by drenching along the roots of the leeks, and immediately irrigate the experimental plot after the root drenching treatment.

[0042] A five-point sampling method was used to investigate the control effect at 7, 14, and 21 days after the application of the pesticide. At each point, two adjacent holes were sampled, with approximately 15-20 maggots per hole. The number of live maggots was recorded, and the control effect was calculated using the following formula:

[0043] The test results are shown in the table below. The control efficacy of the control drug reached 74.47%, 81.70%, and 78.97% at 7, 14, and 21 days after administration, respectively. The control efficacy of Example 1 reached 82.52%, 92.15%, and 88.09%, respectively, which were higher than those of the control drug.

[0044] The experimental results show that the formulation provided by the present invention can increase the effective utilization rate of the drug solution, thereby improving the efficacy of the drug.

[0045] Table 5 Field efficacy trials

[0046] The suspension concentrate containing pyriproxyfen and thiamethoxam provided by this invention exhibits good deposition, strong permeability, and good wetting properties. It increases the penetration depth of the pesticide solution in the soil while also improving its adhesion to roots and bulbs. The suspension concentrate provided by this invention can improve the effective utilization rate of the pesticide solution, thereby enhancing its efficacy.

[0047] Although embodiments of the invention have been disclosed for illustrative purposes, those skilled in the art will understand that various substitutions, variations, and modifications are possible without departing from the spirit and scope of the invention and the appended claims, and therefore the scope of the invention is not limited to the contents disclosed in the embodiments.

Claims

1. A suspension containing pyriproxyfen and thiamethoxam, characterized in that, The suspending agent comprises, by weight percentage, 3-8% pyriproxyfen, 30-40% thiamethoxam, 1-1.5% clove extract, and 0.5-1% astragalus polysaccharide.

2. The suspending agent as described in claim 1, characterized in that, The suspending agent comprises, by weight percentage, 5.1% pyriproxyfen, 34.9% thiamethoxam, 1-1.5% clove extract, and 0.5-1% astragalus polysaccharide.

3. The suspending agent as described in claim 2, characterized in that, The weight ratio of clove extract to astragalus polysaccharide is 3:

2.

4. The suspending agent as described in claim 3, characterized in that, It also includes one or more of the following: dispersants, wetting agents, thickeners, antifreeze agents, preservatives, and solvents.

5. The use of the suspending agent as described in any one of claims 1 to 4 for the prevention and control of leek maggots.

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