A seed treatment suspension and preparation method thereof

Abstract

The present invention relates to the technical field of pesticide preparations, and in particular to a seed treatment suspension and a preparation method thereof. The seed treatment suspension includes: 12-25% thiamethoxam, 1-5% metconazole, 1-5% azoxystrobin, 3-6% film former, 5-40% other benefit additives, water supplemented to 100%, the film former includes an acrylic emulsion, the solid content of the acrylic emulsion is 45-51%, the viscosity of the acrylic emulsion is 9500-9900cPs, and the other benefit additives include at least one of a wetting dispersant, a thickener, a defoamer, a preservative, an antifreeze agent and a warning colorant. The present application adopts an acrylic emulsion with a solid content of 45-51% and a viscosity of 9500-9900cPs, and limits the weight percentage of each component, so that the prepared suspension has a short film-forming time, a coating uniformity of more than 90%, and a coating shedding rate of 5% or less, which helps the original drug in the seed coating to be slowly released in an environment with a high water content, thereby prolonging the persistence of the original drug.

Description

Technical Field

[0001] The invention relates to the technical field of pesticide preparations, in particular to a seed treatment suspending agent and a preparation method thereof. Background Art

[0002] Seed treatment suspension (FS) can effectively and evenly adsorb the original drug, micro-fertilizer, etc. on the seeds by using film-forming agents and other additives. During the seed germination process, the active ingredients slowly decompose into the environment as the film-forming agent degrades to kill insects and bacteria, and are absorbed by plants, which can protect the normal growth of plants. Due to the concentrated drug effect, it is not easily affected by the sun, rain and high temperature, and the drug effect time is longer than other seed treatment methods. It does not affect the germination rate and quality of seedlings, and also significantly reduces the chance of poisoning to natural enemies such as humans, animals, pests, etc., thereby reducing pollution.

[0003] In the related art, seed treatment suspensions generally include components such as the original drug, film-forming agent, dispersant and defoaming agent. Among them, the original drug is the main insecticide component. In order to prevent a variety of diseases and insect pests, the original drug is generally compounded with a variety of pesticides; the film-forming agent and other components form a protective film on the surface of the seeds, adhering the original drug to the surface of the seeds, and then slowly degrade in the soil, and the original drug slowly disperses into the environment. However, when some seed treatment suspensions are used on paddy field crops, due to the high water content in the paddy field, the film-forming agent is easily dissolved and leached, and the original drug will quickly disperse into the environment, reducing the utilization rate of the original drug in the seed treatment suspension and affecting the prevention and control effect. Summary of the invention

[0004] In order to improve the lasting effect of seed treatment suspension on paddy field crops, the present application provides a seed treatment suspension and a preparation method thereof.

[0005] In the first aspect, the present application provides a seed treatment suspension, which adopts the following technical solution:

[0006] A seed treatment suspension comprises the following components in percentage by weight: 12-25% of thiamethoxam, 1-5% of metconazole, 1-5% of azoxystrobin, 3-6% of a film former, 5-40% of other benefit additives, and water is supplemented to 100%. The film former comprises an acrylic emulsion, the solid content of the acrylic emulsion is 45-51%, and the viscosity of the acrylic emulsion is 9500-9900 cPs. The other benefit additives comprise at least one of a wetting dispersant, a thickener, a defoamer, a preservative, an antifreeze agent, and a warning colorant.

[0007] By adopting the above technical scheme, thiamethoxam has stomach poison, contact killing and systemic activity against piercing-sucking pests, which can effectively prevent and control pests. Metconazole has excellent control effects on Septoria, Fusarium and Puccinia plant diseases of cereal crops. Azoxystrobin has good control effects on fungal diseases. Therefore, the use of thiamethoxam, metconazole and azoxystrobin can improve the control effect of suspension on various cereal crop diseases and pests. Other enhancement additives help to adjust the dispersion uniformity, viscosity and fluidity of the suspension. The film-forming agent can form a protective film on the surface of the seeds, so that the above three raw materials are evenly coated on the seed surface and form a seed coat.

[0008] The inventors found that when an acrylic emulsion within the above parameter range is selected, the ratio of the original drug, acrylic emulsion, other benefit additives and water is controlled within the above range, a synergistic effect is produced between the acrylic emulsion and other components, and the resulting suspension does not show obvious paste, pseudoplasticity or wall hanging phenomenon at room temperature, -30°C or 50°C, and the suspension has high stability; and has low surface tension and small particle size, which helps the original drug to spread, wet and adhere to the seeds; when used on wheat or rice seeds, the film forming time is short, the coating uniformity is as high as 90% or more, and the coating shedding rate is as low as 5% or less, which helps the original drug in the seed coating to be slowly released in an environment with high water content, thereby prolonging the persistence of the original drug.

[0009] In a specific embodiment, the film-forming agent further includes at least one of paraffin emulsion or talc.

[0010] By adopting the above technical solution, the inventors found that paraffin emulsion contains multiple waxes such as petroleum wax. When paraffin emulsion is compounded with acrylic emulsion, acrylic emulsion can be further emulsified, the particle size and viscosity of the film-forming agent can be reduced, the coating uniformity can be improved, and the seed soaking condition of the suspension can be improved. After talcum powder, paraffin emulsion and acrylic emulsion are compounded, the coating uniformity and seed soaking condition of the suspension for wheat seeds can also be improved.

[0011] In a specific embodiment, based on the total weight of the seed treatment suspension, the other benefit adjuvants include the following weight percentages: 1-3% of polyarylether ammonium sulfate wetting and dispersing agent, and 1-3% of polycarboxylate wetting and dispersing agent.

[0012] By adopting the above technical solution, the polyarylether ammonium sulfate wetting and dispersing agent contains the active ingredient aryl polyoxyethylene ether sulfate ammonium salt, and the polycarboxylate wetting and dispersing agent contains the active ingredient acrylic acid homopolymer sodium salt, both of which help the original drug to be evenly dispersed in water. In addition, the inventors found that using these two wetting and dispersing agents according to the above weight percentage can not only improve the dispersion effect of the original drug, but also reduce the surface tension of the suspending agent, which is conducive to the spreading and wetting of the suspending agent on the seed surface, and facilitates the adhesion of the original drug to the seed surface; moreover, the suspending agent does not show obvious paste, pseudoplasticity or wall hanging phenomenon at low or high temperatures, and maintains good stability.

[0013] In a specific embodiment, the content of ammonium salt of aromatic polyoxyethylene ether sulfate in the ammonium polyarylether sulfate wetting and dispersing agent is 90-95%, and the content of sodium salt of acrylic acid homopolymer in the polycarboxylate wetting and dispersing agent is 30%-35%.

[0014] By adopting the above technical solution and selecting the polyarylether ammonium sulfate wetting and dispersing agent and the polycarboxylate wetting and dispersing agent with the above active ingredient content, the coating uniformity of the suspension can be further improved and the coating shedding rate can be reduced.

[0015] In a specific embodiment, the weight ratio of the polyarylether ammonium sulfate wetting and dispersing agent to the polycarboxylate wetting and dispersing agent is 1:1.

[0016] By adopting the above technical scheme, when the effective content of the polyarylether ammonium sulfate wetting and dispersing agent and the polycarboxylate wetting and dispersing agent is within the above range, the weight ratio is controlled at 1:1, and the coating uniformity of the obtained suspension is higher and the coating shedding rate is lower. At this time, the suspension helps to improve the germination rate or emergence rate of seeds.

[0017] In a specific embodiment, based on the total weight of the seed treatment suspension, the other benefit adjuvants include the following weight percentage components: 0.7-0.9% thickener, wherein the thickener includes xanthan gum and magnesium aluminum silicate in a weight ratio of 3:(4-6).

[0018] By adopting the above technical solution, the thickener can adjust the fluidity of the suspension and delay the sedimentation of particles in the suspension. The inventors found that by compounding xanthan gum and magnesium aluminum silicate according to the above weight ratio and using them according to the above weight percentage, the suspension rate of the obtained seed treatment suspension is above 99%, the particle size of the seed treatment suspension is small, the viscosity is below 1.30 Pa·s, and the pourability and stability are good. Using the seed treatment suspension at this time helps to further improve the coating uniformity.

[0019] In a specific embodiment, the preservative includes at least one of benzoic acid, kasone preservative, and bromopol.

[0020] By adopting the above technical scheme, benzoic acid, kasone preservative and bropol can improve the antiseptic effect of seed treatment suspension and prolong the effectiveness of seed treatment suspension.

[0021] In a specific embodiment, the seed treatment suspension comprises the following components in weight percentage: 12-25% thiamethoxam, 1-5% metconazole, 1-5% azoxystrobin, 0.1-0.3% benzoic acid, 0.1-0.5% xanthan gum, 0.2-0.8% magnesium aluminum silicate, 8-12% ethylene glycol, 0.3-0.7% silicone defoamer, 0.1-0.5% Bropoel solution with a molar concentration of 10%, 0.1-0.3% Kathon preservative, 3-5% acrylic emulsion, 6-10% warning colorant, 1-3% polycarboxylate dispersant, 1-3% polyarylether ammonium sulfate dispersant, and water is supplemented to 100%.

[0022] By adopting the above technical solution, the inventors studied the addition types and addition amounts of other enhancement additives, and found that the suspension prepared by adopting the above additives and raw material ratios not only exhibits excellent pourability, low temperature stability and thermal storage stability, but also, when used in paddy fields, the film forming time reaches about 14 seconds, the coating uniformity reaches more than 94%, and the coating shedding rate reaches less than 3.5%. The comprehensive performance is good, and it has a good effect on both dryland and paddy field crops, and can improve the germination rate and emergence rate of seeds. This may be because, under the above raw material ratio, the synergistic effect between the polycarboxylate dispersant, the polyarylether sulfate ammonium dispersant, the xanthan gum, the magnesium aluminum silicate and the acrylic emulsion not only improves the dispersion uniformity of the original drug and other additives, but also improves the adhesion rate of the original drug, so that the original drug is evenly attached to the surface of the seed. At the same time, silicone defoamers, benzoic acid, ethylene glycol, Bropol and Kasong preservatives improve the film-forming property, corrosion resistance, low temperature stability and thermal storage stability of the suspension, so that thiamethoxam can adapt to temperatures below -10°C and above 35°C, and overcome the problem of drug damage caused by mixing azoxystrobin with silicone synergists, so that the efficacy is better maintained. In the process of the seed coat gradually dissolving, the original drug is gradually released into the environment, with a longer lasting effect, which can prevent and control pests and diseases for a longer time. In addition, the raw materials used are cheaper, which can also reduce the production cost of the suspension.

[0023] In a specific embodiment, the seed treatment suspension comprises the following components in weight percentage: 18.2% thiamethoxam, 3.2% metconazole, 3.2% azoxystrobin, 0.2% benzoic acid, 0.3% xanthan gum, 0.5% magnesium aluminum silicate, 10% ethylene glycol, 0.5% silicone defoamer, 0.3% Brobol solution with a molar concentration of 10%, 0.2% kason, 4% acrylic emulsion, 8% 8# red, 2% polycarboxylate dispersant, 2% polyarylether ammonium sulfate dispersant, and water is supplemented to 100%.

[0024] By adopting the above technical solution, the inventors further screened the types of adjuvants and raw material ratios and found that the suspension concentrate prepared by adopting the above adjuvants and raw material ratios has better comprehensive performance, and when used, the germination rate and emergence rate of seeds are higher.

[0025] In a second aspect, the present application provides a method for preparing a seed treatment suspension, using the following technical solution:

[0026] A method for preparing a seed treatment suspension comprises the following steps:

[0027] Thiamethoxam, metconazole, azoxystrobin, a film-forming agent, other benefit additives and water are mixed, sheared and ground to an average particle size of 1-5 μm to obtain a seed treatment suspension.

[0028] By adopting the above technical scheme, the average particle size of the suspending agent is controlled at 1-5μm, which can improve the suspension rate of the suspending agent, delay the sedimentation of particles, and reduce the surface tension of the suspending agent, which helps the suspending agent to spread and wet on the seeds, improve the film-forming performance, and further improve the germination rate and emergence rate of the seeds.

[0029] In summary, the present application includes at least one of the following beneficial technical effects:

[0030] 1. The present application adopts an acrylic emulsion with a solid content of 45-51% and a viscosity of 9500-9900 cPs, and limits the weight percentage of each component. The prepared suspension has a short film-forming time, a coating uniformity of more than 90%, and a coating shedding rate of 5% or less, which helps the original drug in the seed coating to be slowly released in an environment with a high water content, thereby prolonging the persistence of the original drug;

[0031] 2. The present application adopts a compound of polyarylether ammonium sulfate wetting and dispersing agents and polycarboxylate wetting and dispersing agents, which can not only improve the dispersion effect of the original drug, but also reduce the surface tension of the suspending agent, which is conducive to the spreading and wetting of the suspending agent on the seed surface, making it easier for the original drug to adhere to the seed surface, and helping to improve the germination rate or emergence rate of the seeds;

[0032] 3. The present application adopts a compound of xanthan gum and magnesium aluminum silicate, which helps to improve the suspension rate and fluidity of the suspending agent and delay the sedimentation of particles in the suspending agent. DETAILED DESCRIPTION

[0033] The raw materials used in the specific implementation of the present application are all commercially available. Among them, the effective ingredient content of thiamethoxam is 98%, the effective ingredient content of metconazole is 95%, and the effective ingredient content of azoxystrobin is 97%. The content of acrylic acid homopolymer sodium salt in GEROPON DA1349 type polycarboxylate wetting dispersant is 30%-35%; the content of aromatic polyoxyethylene ether sulfate ammonium salt in FD530 type polyarylether sulfate ammonium dispersant is 90-95%.

[0034] Rice and wheat are two of the three major economic crops in the country, and ensuring their high and stable yields has important social significance. Factors such as stem base diseases and aphids are becoming increasingly rampant, seriously affecting the growth of plants. At present, seed treatment in chemical control is the main measure for the prevention and control of rice and wheat. The inventor found that the film-forming agent of the traditional seed treatment suspension is easy to dissolve and leached during the use of paddy fields, which reduces the utilization rate of the effective components of the pesticide and affects the control effect. Therefore, the development of a seed coating agent with a film-forming agent that has good film-forming properties, is degradable, has a long lasting effect, has a high germination rate, good biological activity and efficacy, and is low in price has become an urgent issue in the current agricultural and environmental protection fields. The inventor made a compound seed treatment suspension of three pesticides, thiamethoxam, metconazole, and myclobutanil, for two crops, rice and wheat. Through the formula screening and process research of the seed treatment suspension, the optimal formula and production process conditions were determined to extend the lasting effect of the agent. In the following study, the preparation index detection method is as follows:

[0035] Determination of sample surface tension: dilute the prepared suspended seed coating agent into a 20-fold aqueous solution and measure its surface tension using a surface tension meter.

[0036] Viscosity determination: Use BROOKFIELD R / S plus rheometer to measure, inject the suspended seed coating sample into the measurement container, and measure the viscosity of the sample at a shear rate of 400 (1 / s). Ambient temperature: 25°C; relative humidity: 30%. Use a digital rotational viscometer, select an appropriate rotor, and measure the viscosity of the sample at a speed of 30r / min.

[0037] Determination of particle size: The average particle size D90 and particle size distribution of the samples were determined using a Malvern Master Sizer 2000 laser particle size analyzer.

[0038] Determination of film-forming time: Determine the film-forming time of the sample coated seeds according to the film-forming time method in GB / T 17768-1999.

[0039] Determination of coating uniformity: Determine the uniformity of sample coated seeds according to the coating uniformity method in GB / T 17768-1999.

[0040] Determination of shedding rate: Determine the shedding rate of sample coated seeds according to the shedding rate method in GB / T 17768-1999.

[0041] Low temperature stability determination: Determine according to CIPAC MT39.2 method, record the phenomena such as stratification and crystallization.

[0042] Hot storage stability determination: Determine according to CIPAC MT46.1 method, record the phenomena such as stratification, agglomeration, fluidity, etc.

[0043] The most important part of film-forming agent selection is whether the seed coat can regulate the rapid changes in water and air permeability. When covering the seed coat, the original vitality must be maintained, and new performance must be added under good survival regulation. Therefore, the key to the preparation of seed treatment suspension is the appropriate film-forming agent.

[0044] The inventors conducted research on a single film-forming agent. As shown in Table 1, the single film-forming agent acrylic emulsion n8 has good performance, with a film-forming time of 14 minutes, a shedding rate of 3.24%, and a coating uniformity of 90% and 95% for wheat and rice seeds, respectively. The solid content of acrylic emulsion n8 is 45-51%, and the viscosity (25°C, 2# rotor, 3 rpm) is 9500-9900 cPs.

[0045] Table 1 Screening of single film-forming agent for seed treatment suspension

[0046]

[0047]

[0048] According to the screening results of the single agent, the inventor hopes to further add other additives to improve the film-forming performance, and hopes that the added other additives can reduce the cost of the film-forming agent while improving the performance. Therefore, the inventor studied the compounding of the film-forming agent. It can be seen from Table 2 that acrylic emulsion n8 + paraffin emulsion and acrylic emulsion n8 + talcum powder + paraffin emulsion have the best performance, but considering the performance and cost of acrylic emulsion n8, the mixed agent cost of acrylic emulsion n8 is higher than that of acrylic emulsion n8 alone. Therefore, acrylic emulsion n8 is selected as the film-forming agent of the seed treatment suspension.

[0049] Table 2 Screening of film-forming agent mixtures for seed treatment suspensions

[0050]

[0051]

[0052] Then, the inventors screened the types of wetting and dispersing agents. Currently, the most commonly used method to determine the types of wetting and dispersing agents is the flow point method. The higher the activity of the dispersant, the lower the flow point; the finer the solid active material, the higher its flow point; therefore, the one with the smallest flow point is the best wetting and dispersing agent required for the preparation. The inventors used the flow point method to screen 12 wetting and dispersing agents: YUS-FS3000, POLIZROLTS6, FD530, 343C, TensionfixDB08DL, MADEOLMW, PICO-JS41M, GreensperseNA, PB08SC, EmulsonAG / PE, GEROPONDA1349, and ZX-556. The results are shown in Table 3.

[0053] The method for determining the flow point of a wetting and dispersing agent is as follows: prepare a 5% wetting and dispersing agent aqueous solution, add 5.0g (accurate to 0.001g) of crushed test original drug (average particle size of about 45μm) in a small beaker, slowly drip the prepared wetting and dispersing agent solution with a dropper, and carefully mix with a glass rod while dripping until the mixed paste can drip freely from the glass rod, record the mass of the wetting and dispersing agent aqueous solution dripped (accurate to 0.001g), and repeat 3 times. The flow point of the wetting and dispersing agent to the test original drug is obtained by dividing the mass of the wetting and dispersing agent aqueous solution dripped by the mass of the test original drug.

[0054] Table 3 Flow point determination results of wetting dispersant for seed treatment suspension

[0055]

[0056]

[0057] The results show that the flow points of naphthalenesulfonate dispersants (Tensionfix DB08DL, MADEOL MW) are relatively large and are not suitable as wetting dispersants for seed treatment suspensions. The flow points of phosphate wetting dispersants, polyarylether ammonium sulfate dispersants, lignin naphthalenesulfonate dispersants, block polyether wetting dispersants, and polycarboxylate dispersants are relatively small.

[0058] Although the flow point method is intuitive and specific, it is not easy to distinguish wetting dispersants with similar dispersion effects and is only suitable for the initial screening of wetting dispersants. Therefore, considering the synergistic effect of surfactants, the commonly used wetting dispersant combinations are used to optimize the combination through flow point, hot storage performance, and cold storage performance. The results are shown in Tables 4 and 5.

[0059] Table 4 Flow point determination results of the wetting and dispersing agent combination of seed treatment suspension

[0060]

[0061] Table 5 Comprehensive index results of wetting and dispersing agent combination of seed treatment suspension (1)

[0062]

[0063]

[0064]

[0065] From Tables 4 and 5, it can be seen that 9 combinations of FD530+GEROPON DA1349, FD530+ZX-556, POLIZROLTS6+EmulsonAG / PE, YUS-FS3000+GEROPON DA1349, YUS-FS3000+ZX556, POLIZROLTS6+ZX-556, 343C+GEROPON DA1349, 343C+ZX-556, and PICO-JS41M+ZX556 did not show the characteristics of creaming / pseudoplasticity in hot storage, and there was no good phenomenon of wall hanging in cold storage. Although there are differences between these 9 groups, the differences are not significant, and the optimal formula needs to be screened out from the wetting and dispersing agent compound. Therefore, the inventors further confirmed it by using the optimized combination method again through microscopic surface tension, particle size, pH and wet screening data, and the results are shown in Table 6.

[0066] Table 6 Comprehensive index results of wetting and dispersing agent combination of seed treatment suspension (2)

[0067]

[0068]

[0069] The screening results in Table 6 show that the combination of FD530+GEROPON DA1349 is better. According to Stokes' law, a suspension system with a smaller particle size and a narrower particle spectrum is more stable; in addition, a small surface tension at the microscopic level is conducive to the spreading and wetting of the agent on the seeds, and is conducive to the adhesion of the agent on the seeds. A low water separation rate at the macroscopic level indicates better stability. The particle size and particle spectrum, surface tension, wet screening, and pH of the FD530+GEROPON DA1349 combination performed best among all the tested combinations, indicating that this combination is the best match with the original drug. Therefore, the FD530+GEROPON DA1349 combination was determined to be the best wetting and dispersing agent for seed treatment suspensions, and the wetting and dispersing agent ratio was screened on this basis.

[0070] Under the determined dosage, for a given adjuvant and technical medium, different wetting and dispersing agent ratios will change with the help of adsorption at the solid-liquid interface. The concentration ratio of the added surfactant will have an optimal value. When it exceeds or is lower than this concentration ratio, its hydrophilicity may decrease, which is not conducive to dispersion and wetting, and reduces the market competitiveness of the product. It is of great significance to conduct in-depth and accurate determination of the concentration ratio. By compounding the two wetting and dispersing agents FD530 and GEROPON DA1349 in different compounding ratios, and keeping the other adjuvants unchanged, the flow of the preparation and the seed coating were preliminarily observed and screened, and orthogonal analysis was performed to determine the three better compounding ratios of the two, and the correct concentration ratio was accurately determined. As shown in Table 7, when FD530: GEROPON DA1349 = 1:1, the dispersibility and stability are better, which meets the requirements of the suspension.

[0071] Table 7 Screening of wetting and dispersing agent ratios for seed treatment suspensions

[0072]

[0073] The inventors also screened thickeners. Thickeners are widely used in pesticide suspensions because they have the function of increasing the viscosity of the system and helping the original drug particles to suspend. Adding thickeners to the formula can delay the sedimentation of particles. The amount of thickeners added should be well controlled, requiring the product to have good fluidity and not affect the pourability of the product. By compounding xanthan gum (XG) and aluminum magnesium silicate (SB) with different compounding ratios of the two thickeners, and keeping the other auxiliary agents unchanged, the viscosity of the preparations was preliminarily observed and screened, and orthogonal analysis was performed to determine the three better compounding ratios of the two, and the correct concentration ratio was accurately determined, as shown in Table 8.

[0074] Table 8 shows that when the ratio of xanthan gum: aluminum magnesium silicate = 0.3:0.5 is used, a firm gel scaffold structure can be formed in the preparation system when the product is left at rest, which helps stabilize the system, and it can become a fluid when vibrated and shaken, without affecting the fluidity of the preparation product, thereby playing a role in aiding suspension.

[0075] Table 8 Screening of thickener ratios for seed treatment suspensions

[0076]

[0077] The present application is further described in detail below with reference to the embodiments.

[0078] Example

[0079] Example 1

[0080] The present embodiment provides a seed treatment suspension, comprising the following components in weight percentage: 18.2% thiamethoxam, 3.2% metconazole, 3.2% azoxystrobin, 4% acrylic emulsion, 4% GEROPON DA1349 polycarboxylate dispersant, 8% 8# red, and deionized water to 100%. The acrylic emulsion has a solid content of 48% and a viscosity (25°C, 2# rotor, 3 rpm) of 9700 cPs.

[0081] The preparation method of the seed treatment suspension is as follows: according to the above ratio, thiamethoxam, metconazole, myclobutanil, acrylic emulsion, polycarboxylate dispersant and deionized water are added to a raw material mixing tank, a high-speed shearing machine is turned on for initial grinding for 30 minutes, and then poured into a sand mill and mixed with a grinding medium to be evenly ground, and the sample particle size is tested. When the particle size of more than 95% of the particles is 1 to 5 μm and the average particle size reaches less than 3 μm, the sand milling is terminated, and the drug solution and the grinding medium are separated and filtered to obtain a seed treatment suspension.

[0082] Example 2

[0083] This embodiment provides a seed treatment suspension, which is different from the first embodiment in that the seed treatment suspension comprises the following components in weight percentage: 18.2% thiamethoxam, 3.2% metconazole, 3.2% azoxystrobin, 4% acrylic emulsion, 8% 8# red, 2% GEROPON DA1349 polycarboxylate dispersant, 2% FD530 polyarylether ammonium sulfate dispersant, and deionized water is added to 100%. In the preparation method of the seed treatment suspension, the FD530 polyarylether ammonium sulfate dispersant and the GEROPON DA1349 polycarboxylate dispersant are added to the raw material mixing tank simultaneously.

[0084] Example 3

[0085] The present embodiment provides a seed treatment suspension, which is different from the first embodiment in that the seed treatment suspension comprises the following components in weight percentage: 18.2% thiamethoxam, 3.2% metconazole, 3.2% azoxystrobin, 4% acrylic emulsion, 8% 8# red, 2% GEROPON DA1349 polycarboxylate dispersant, 2% FD530 polyarylether ammonium sulfate dispersant, 0.3% xanthan gum, 0.5% magnesium aluminum silicate, and deionized water is added to 100%. In the preparation method of the seed treatment suspension, the FD530 polyarylether ammonium sulfate dispersant, xanthan gum, magnesium aluminum silicate and the GEROPON DA1349 polycarboxylate dispersant are added to a raw material mixing tank simultaneously.

[0086] Example 4

[0087] This embodiment provides a seed treatment suspension, which is different from the first embodiment in that 18.2% of thiamethoxam, 3.2% of metconazole, 3.2% of azoxystrobin, 0.2% of benzoic acid, 0.3% of xanthan gum, 0.5% of magnesium aluminum silicate, 10% of ethylene glycol, 0.5% of BG08 type silicone defoamer, 0.3% of Brobol solution with a molar concentration of 10%, 0.2% of Kasson preservative, 4% of acrylic emulsion, 8% of 8# red, 2% of GEROPON DA1349 type polycarboxylate dispersant, 2% of FD530 type polyarylether sulfate ammonium dispersant, and water is added to 100%. In the preparation method of the seed treatment suspension, the above-mentioned various components are simultaneously added into the raw material mixing tank.

[0088] Example 5

[0089] This embodiment provides a seed treatment suspension, which is different from the first embodiment in that 12% thiamethoxam, 1% metconazole, 1% azoxystrobin, 0.1% benzoic acid, 0.1% xanthan gum, 0.2% magnesium aluminum silicate, 8% ethylene glycol, 0.3% BG08 type silicone defoamer, 0.1% Brobol solution with a molar concentration of 10%, 0.1% Kasson preservative, 3% acrylic emulsion, 6% 8# red, 1% GEROPON DA1349 type polycarboxylate dispersant, 1% FD530 type polyarylether sulfate ammonium dispersant, and water is added to 100%. In the preparation method of the seed treatment suspension, the above-mentioned various components are simultaneously added into the raw material mixing tank.

[0090] Example 6

[0091] This embodiment provides a seed treatment suspension, which is different from the first embodiment in that 25% thiamethoxam, 5% metconazole, 5% azoxystrobin, 0.3% benzoic acid, 0.5% xanthan gum, 0.8% magnesium aluminum silicate, 12% ethylene glycol, 0.7% BG08 type silicone defoamer, 0.5% Brobol solution with a molar concentration of 10%, 0.3% Kasson preservative, 5% acrylic emulsion, 10% 8# red, 3% GEROPON DA1349 type polycarboxylate dispersant, 3% FD530 type polyarylether sulfate ammonium dispersant, and water is added to 100%. In the preparation method of the seed treatment suspension, the above-mentioned various components are simultaneously added into the raw material mixing tank.

[0092] Performance testing

[0093] Seed treatment suspension index detection: Referring to the national standard "GB / T17768-1999 Specification for the Preparation of Suspension Seed Coating Product Standards" and the Ministry of Agriculture's similar product standard "NY621-2002 Dofok Suspension Seed Coating", the physical and chemical properties and coating performance of the seed treatment suspensions of Examples 1-6 were tested. The test results are shown in Table 9.

[0094] Safety test of seed treatment suspension: The indoor test method for evaluating the safety of fungicides and insecticides on crops in NY / T1965.1-2010 was adopted to carry out coating test on the seed treatment suspension obtained in Example 4, and the germination rate, germination potential and emergence of wheat and rice seeds were recorded. The results are shown in Tables 10 and 11.

[0095] Table 9 Physicochemical properties and coating properties of seed treatment suspension concentrates of Examples 1-6

[0096]

[0097] Table 10 Safety test of seed treatment suspension concentrate for wheat in Example 4

[0098]

[0099]

[0100] Table 11 Safety test of seed treatment suspension concentrate for rice in Example 4

[0101]

[0102] Combining Examples 1-6 and Table 9, it can be seen that the suspension rates of the seed treatment suspensions of Examples 1-6 are all greater than 90%, the particle sizes are less than 3 microns, the coating uniformity is greater than 90%, the coating shedding rate is less than 5%, and the film forming properties, low temperature stability and thermal storage stability are all qualified. This shows that the seed treatment suspensions prepared under the raw material ratios and process conditions of Examples 1-6 all have excellent performance, which helps to improve the sustained effect of the seed treatment suspensions on paddy field crops, and the seed treatment suspension prepared under the preparation conditions of Example 4 has the best performance.

[0103] It can be seen from Tables 10-11 that the seed treatment suspension of Example 6 has a good control effect on both wheat and rice. With the increase of the seed treatment suspension coating dosage, the germination rate and emergence rate of wheat seeds gradually decreased, with significant differences. Within the range of 500g / 100kg seeds-1000g / 100kg seeds, the requirements for seed safety can be met. At the remaining dosages, the germination rate and emergence rate requirements are not met. For rice seeds, within the range of 500g / 100kg seeds-2000g / 100kg seeds, the requirements for seed safety can be met. Therefore, the recommended dosage is 500g / 100kg seeds-1000g / 100kg seeds.

[0104] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A seed treatment suspending agent, characterized in that: The invention comprises the following components in weight percentage: 12-25% of thiamethoxam, 1-5% of metconazole, 1-5% of azoxystrobin, 3-6% of film former, 5-40% of other benefit additives, and water is added to 100%, wherein the film former comprises acrylic emulsion n8, and the other benefit additives comprise wetting and dispersing agent, thickener, defoamer, preservative, antifreeze agent and warning colorant; Based on the total weight of the seed treatment suspension, the wetting and dispersing agent is 1-3% of the FD530 type polyarylether ammonium sulfate wetting and dispersing agent and 1-3% of the GEROPON DA1349 type polycarboxylate wetting and dispersing agent; the weight ratio of the FD530 type polyarylether ammonium sulfate wetting and dispersing agent to the GEROPON DA1349 type polycarboxylate wetting and dispersing agent is 1:1; Based on the total weight of the seed treatment suspension, the total amount of the thickener is 0.7-0.9%, and the thickener is xanthan gum and magnesium aluminum silicate in a weight ratio of 3:(4-6).

2. A seed treatment suspending agent according to claim 1, characterized in that: The film-forming agent further comprises at least one of paraffin emulsion or talc.

3. A seed treatment suspending agent according to claim 1, characterized in that: The preservative includes at least one of benzoic acid, kasone preservative, and bromopol.

4. A seed treatment suspending agent according to claim 3, characterized in that: The seed treatment suspension comprises the following components in weight percentage: 12-25% of thiamethoxam, 1-5% of metconazole, 1-5% of azoxystrobin, 0.1-0.3% of benzoic acid, 0.1-0.5% of xanthan gum, 0.2-0.8% of magnesium aluminum silicate, 0.7-0.9% of the total amount of thickener, 8-12% of ethylene glycol, 0.3-0.7% of organic silicon defoamer, 0.1-0.5% of Bropoer solution with a molar concentration of 10%, 0.1-0.3% of Kathon preservative, 3-5% of acrylic emulsion n8, 6-10% of warning colorant, 1-3% of GEROPON DA1349 polycarboxylate wetting and dispersing agent, 1-3% of FD530 polyarylether ammonium sulfate wetting and dispersing agent, and water is supplemented to 100%.

5. A seed treatment suspending agent according to claim 4, characterized in that: The seed treatment suspension comprises the following components in percentage by weight: 18.2% of thiamethoxam, 3.2% of metconazole, 3.2% of azoxystrobin, 0.2% of benzoic acid, 0.3% of xanthan gum, 0.5% of magnesium aluminum silicate, 10% of ethylene glycol, 0.5% of an organosilicon defoamer, 0.3% of a 10% molar concentration of Brobol solution, 0.2% of Kasson, 4% of acrylic emulsion n8, 8% of 8# red, 2% of a GEROPON DA1349 polycarboxylate wetting and dispersing agent, 2% of a FD530 polyarylether ammonium sulfate wetting and dispersing agent, and water is added to 100%.

6. A method for preparing a seed treatment suspension according to any one of claims 1 to 5, characterized in that: Thiamethoxam, metconazole, azoxystrobin, a film-forming agent, other benefit additives and water are mixed, sheared and ground to an average particle size of 1-5 μm to obtain a seed treatment suspension.

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