Composition for controlling rice sheath blight disease

Abstract

The invention relates to the technical field of rice compositions, and discloses a composition for controlling rice sheath blight disease, which is prepared from the following raw materials in parts by weight: 5 to 15 parts of thifluzamide, 3 to 10 parts of epoxiconazole, 0.01 to 0.1 part of pimacol, 1.5 to 5 parts of suspending aid, 2 to 5 parts of dispersing aid, 8 to 15 parts of nutrition carrier and settling aid, 10 to 20 parts of filling agent and 0.1 to 0.5 part of anti-blocking agent. Two bactericides including thifluzamide and epoxiconazole are compounded with a sodium naphthalene acetate plant growth regulator, the thifluzamide prevents growth and reproduction of hyphae by inhibiting respiratory action of germs, and the epoxiconazole destroys cell membrane structures of the germs to kill the germs, has systemic property and is also effective for the germs invading into tissues; meanwhile, the sodium naphthalene acetate promotes the growth of rice roots, so that the rice sheath blight disease can be effectively controlled, the growth of the rice can be promoted on the whole, the stress resistance of the rice is improved, and the dual effects of preventing and treating diseases and promoting growth are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of rice compositions, in particular to a composition for controlling rice sheath blight. Background Art

[0002] Rice sheath blight is a soil-borne fungal disease caused by Rhizoctonia solani. It may occur at all stages of rice cultivation, especially in the middle and late stages of rice growth, when it is very likely to break out under high temperature and high humidity conditions. The disease mainly harms the leaf sheaths, leaves and stems of rice. In the early stage, small dark green spots like water stains appear on the leaf sheaths near the water surface, and then gradually expand into oval or cloud-like spots. The edges of the spots are brown and the center is grayish white. As the disease progresses, the spots merge with each other, causing the leaf sheaths and leaves to dry up, the stems to soften and fall over, seriously affecting the photosynthesis and nutrient transport of rice, and ultimately leading to a reduction in rice production. It can generally cause a reduction in production, which greatly threatens the safe production of rice.

[0003] In the current technology, a single fungicide is used to control rice sheath blight, which is too one-sided and ignores the comprehensive impact on rice growth, which can easily lead to drug resistance in the pathogen and gradually reduce the control effect. Summary of the invention

[0004] In view of the deficiencies of the prior art, the present invention provides a composition for controlling rice sheath blight, which solves the problem that the control of rice sheath blight is too one-sided, ignoring the comprehensive impact on rice growth, resulting in a gradual decline in the prevention and control effect.

[0005] To achieve the above objectives, the present invention is implemented through the following technical scheme: a composition for controlling rice sheath blight, comprising the following raw materials in parts by weight: 5-15 parts of thiophanate-methyl, 3-10 parts of fluconazole, 0.01-0.1 parts of sodium naphthylacetate, 1.5-5 parts of a suspension aid, 2-5 parts of a dispersion aid, 8-15 parts of a nutrient carrier and a sedimentation aid, 10-20 parts of a filler and 0.1-0.5 parts of an anti-caking agent.

[0006] Preferably, the suspension aid includes sodium carboxymethyl cellulose and polyvinyl alcohol, the sodium carboxymethyl cellulose is 1-3 parts, the polyvinyl alcohol is 0.5-2 parts, the dispersing aid is sodium dodecyl sulfate, the nutrient carrier and sedimentation aid include potassium humate and attapulgite, the potassium humate is 5-10 parts, and the attapulgite is 5-10 parts.

[0007] Preferably, the filler is light calcium carbonate, and the anti-caking agent is calcium stearate.

[0008] A method for preparing a composition for controlling rice sheath blight comprises the following steps:

[0009] S1. Preparation of suspension aid: Slowly add the weighed sodium carboxymethyl cellulose into deionized water, stirring while adding, until the sodium carboxymethyl cellulose is completely dissolved to form a uniform transparent solution; meanwhile, in another container, add polyvinyl alcohol into water, heat and stir until the polyvinyl alcohol is completely dissolved to obtain a polyvinyl alcohol solution; then mix the two solutions together, stir evenly, and form a suspension aid mixed solution;

[0010] S2. Preparation of dispersing aid solution: adding sodium dodecyl sulfate into water and stirring to dissolve it to obtain a sodium dodecyl sulfate solution;

[0011] S3, pretreatment of nutrient carrier and sedimentation aid: potassium humate and attapulgite are crushed separately, screened, and then mixed;

[0012] S4, mixing and stirring: adding thiofuran, epoxiconazole and sodium naphthylacetate to the suspension aid mixed solution and stirring and mixing, then adding the dispersion aid solution and the mixed nutrient carrier and sedimentation aid to the system and stirring to form a uniform paste;

[0013] S5, filling and anti-caking treatment: adding light calcium carbonate to the above paste, dispersing it evenly in the system, then adding calcium stearate, and continuing to stir to evenly distribute the calcium stearate to prevent the composition from agglomerating during storage;

[0014] S6. Post-treatment: drying the final mixture by vacuum drying, and then crushing and sieving the dried material to prepare a wettable powder, thereby obtaining the composition for controlling rice sheath blight.

[0015] Preferably, when the polyvinyl alcohol solution in S1 is prepared, the water temperature is controlled at 80-90° C. and the stirring speed is 400-600 rpm.

[0016] Preferably, in the process of S2, sodium dodecyl sulfate is added in multiple times, the time interval between each addition is about 1-2 minutes, and the stirring time is continuous for 10-20 minutes.

[0017] Preferably, the mesh size of the sieve after the potassium humate and attapulgite in S3 are crushed is 80-100 meshes.

[0018] Preferably, the stirring speed during the paste formation process in S4 is 500-700 rpm, the stirring is continued for 30-60 minutes, and the temperature is controlled at 20-30°C.

[0019] Preferably, the stirring speed of the light calcium carbonate and the paste in S5 is 200-400 rpm, and the stirring speed of the calcium stearate mixing is controlled at 100-300 rpm.

[0020] Preferably, the temperature of the vacuum drying equipment in S6 is controlled at 60-80°C, the vacuum degree is set at 0.08-0.09MPa, and the drying is determined to be complete when the water content is less than 5%. The mesh number of the sieve is 200-325 meshes.

[0021] The present invention provides a composition for controlling rice sheath blight, which has the following beneficial effects:

[0022] 1. The present invention compounded two fungicides, thiofuran and epoxiconazole, with a sodium naphthylacetate plant growth regulator. Thifuran inhibited the respiration of pathogens to prevent the growth and reproduction of mycelium. Epoxiconazole destroyed the cell membrane structure of pathogens and killed the pathogens. It is also systemic and effective against pathogens that invaded tissues. At the same time, sodium naphthylacetate promoted the growth of rice roots, thereby effectively controlling rice sheath blight and promoting rice growth as a whole, improving the stress resistance of rice itself, and achieving the dual effects of preventing and controlling diseases and promoting growth.

[0023] 2. The present invention ensures that the composition can be evenly diffused in the rice field with the water flow through the suspension aid and the dispersion aid, thereby increasing the coverage of rice and improving the control effect of sheath blight. At the same time, in the later stage of the composition acting on the water surface, the nutrient carrier and the sedimentation aid can promote the nutrients and remaining effective ingredients to sink to the roots of rice, thereby achieving nutrient supplementation for the roots and improving the comprehensive performance and use effect of the composition.

[0024] 3. The present invention removes moisture slowly and steadily through vacuum drying, and after drying, the composition is crushed into fine and uniform particles to prepare a wettable powder, thereby increasing the specific surface area of ​​the composition, improving the dissolution rate and dispersibility of the composition in water, and enabling the composition to take effect faster. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The present invention is a flow chart of a method for preparing a composition for controlling rice sheath blight. DETAILED DESCRIPTION

[0026] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] Please refer to the attached Figure 1The embodiment of the present invention provides a composition for controlling rice sheath blight, comprising the following raw materials in parts by weight: 5-15 parts of thiophanate-methyl, 3-10 parts of fluconazole, 0.01-0.1 parts of sodium naphthylacetate, 1.5-5 parts of a suspension aid, 2-5 parts of a dispersion aid, 8-15 parts of a nutrient carrier and a sedimentation aid, 10-20 parts of a filler, and 0.1-0.5 parts of an anti-caking agent.

[0028] The suspension aids include sodium carboxymethyl cellulose and polyvinyl alcohol, with the sodium carboxymethyl cellulose accounting for 1-3 parts and the polyvinyl alcohol accounting for 0.5-2 parts. The dispersion aid is sodium dodecyl sulfate. The nutrient carrier and sedimentation aids include potassium humate and attapulgite, with the potassium humate accounting for 5-10 parts and the attapulgite accounting for 5-10 parts.

[0029] The filler is light calcium carbonate and the anti-caking agent is calcium stearate.

[0030] Specifically, thiofuran is a highly effective fungicide, a succinate dehydrogenase inhibitor, which exerts its fungicidal effect by inhibiting the respiration of pathogens. It has a strong specific inhibitory effect on rice sheath blight pathogens, and can effectively prevent the growth and reproduction of pathogen hyphae. Moreover, thiofuran can exert its fungicidal effect on the surface of rice plants, water surface and soil, inhibiting further infection of pathogens and reducing the rice disease index.

[0031] Fluoxepiconazole: Fluoxepiconazole is a triazole fungicide that kills bacteria by inhibiting the synthesis of ergosterol in bacterial cells, destroying the structure and function of cell membranes. It has good systemic properties and can be absorbed by rice and conducted in the plant body. It can also work on bacteria that have invaded rice tissues;

[0032] Sodium naphthylacetate: Sodium naphthylacetate is an auxin-type plant growth regulator that can promote cell division and elongation. In rice growth, it is particularly effective in promoting root growth and can also regulate the growth of the aboveground part of rice. When the composition is suspended on the water surface to exert a bactericidal effect, low levels of sodium naphthylacetate can be absorbed by the rice root system and stem base, regulating the growth of rice and keeping the rice in a good growth state during the disease resistance period;

[0033] Suspension aids: including sodium carboxymethyl cellulose and polyvinyl alcohol. Sodium carboxymethyl cellulose is a water-soluble polymer compound. It forms hydrogen bonds with water molecules through carboxyl and hydroxyl groups on the molecular chain to increase the viscosity of the solution, thereby playing a role in thickening and suspension. It can form a stable suspension system on the water surface to prevent the particles of the composition from settling too quickly. Polyvinyl alcohol has excellent film-forming and adhesion properties and can also increase the viscosity of the solution. In the composition system, polyvinyl alcohol can form a thin film on the water surface, which helps to maintain the suspension state of the composition and make the composition have a better adhesion effect on the surface of rice plants. The two work together to ensure that the composition can be evenly distributed in the rice field with the water flow, improve the coverage rate of rice, and improve the control effect of sheath blight;

[0034] Dispersing aid: Sodium dodecyl sulfate can reduce the surface tension between the composition and water, making the composition particles more easily dispersed in water, and making the composition quickly dispersed into tiny particles, which is conducive to the uniform diffusion of the composition in the rice field along with the water flow. This not only increases the contact probability between the composition and the sheath blight pathogen, making the sterilization effect more comprehensive, but also ensures the stability of the composition in water, avoiding the reduction of drug efficacy due to particle agglomeration;

[0035] Nutrient carrier and sedimentation aid: including potassium humate and attapulgite. Potassium humate is an organic potassium fertilizer, rich in functional groups, with good adsorption and chelation properties. It can adsorb effective ingredients and other nutrients to form a stable nutrient complex. When the composition is suspended on the water surface, it acts as a nutrient carrier to slowly release the effective ingredients to maintain the efficacy. When the composition is consumed, potassium humate and the adsorbed nutrients sink to the roots of rice, providing potassium and other organic nutrients to the roots and promoting the growth of rice roots. Attapulgite is a clay mineral with a special crystal structure, with a large specific surface area and adsorption. It can be used as a carrier to adsorb the effective ingredients and nutrients in the composition. At the same time, its own density is large, which helps the composition sink to the roots of rice after consumption. The two work synergistically to ensure the slow release of effective ingredients and the stable performance of the efficacy in the suspension stage of the composition. When the composition is in the later stage of action, they can promote the nutrients and remaining effective ingredients to sink to the roots of rice to achieve nutritional supplementation of the roots, which is conducive to the growth and development of the rice root system and enhances the stress resistance of rice.

[0036] Filler: light calcium carbonate, which can make the composition have good physical properties during preparation and use, adjust the overall density of the composition to match the density of water, and facilitate the suspension and uniform distribution of the composition on the water surface;

[0037] Anti-caking agent: calcium stearate, which has good anti-caking performance. It can form a hydrophobic film on the surface of the composition particles to prevent the composition particles from agglomerating due to moisture absorption. During the storage and use of the composition, calcium stearate can keep the composition loose, ensuring that the composition can be evenly dispersed on the water surface of the paddy field when sprayed, which is conducive to the suspension of the composition and the exertion of the efficacy. This is very important for the long-term storage and use of the composition under different environmental conditions, ensuring the quality of the composition and the stability of the use effect.

[0038] A method for preparing a composition for controlling rice sheath blight comprises the following steps:

[0039] S1. Preparation of suspension aid: Slowly add the weighed sodium carboxymethyl cellulose into deionized water, stirring while adding, until the sodium carboxymethyl cellulose is completely dissolved to form a uniform transparent solution; meanwhile, in another container, add polyvinyl alcohol into water, heat and stir until the polyvinyl alcohol is completely dissolved to obtain a polyvinyl alcohol solution; then mix the two solutions together, stir evenly, and form a suspension aid mixed solution;

[0040] S2. Preparation of dispersing aid solution: adding sodium dodecyl sulfate into water and stirring to dissolve it to obtain a sodium dodecyl sulfate solution;

[0041] S3, pretreatment of nutrient carrier and sedimentation aid: potassium humate and attapulgite are crushed separately, screened, and then mixed;

[0042] S4, mixing and stirring: adding thiofuran, epoxiconazole and sodium naphthylacetate to the suspension aid mixed solution and stirring and mixing, then adding the dispersion aid solution and the mixed nutrient carrier and sedimentation aid to the system and stirring to form a uniform paste;

[0043] S5, filling and anti-caking treatment: adding light calcium carbonate to the above paste, dispersing it evenly in the system, then adding calcium stearate, and continuing to stir to evenly distribute the calcium stearate to prevent the composition from agglomerating during storage;

[0044] S6. Post-treatment: drying the final mixture by vacuum drying, and then crushing and sieving the dried material to prepare a wettable powder, thereby obtaining the composition for controlling rice sheath blight.

[0045] Specifically, after the sodium carboxymethyl cellulose in S1 is dissolved in water, the viscosity of the solution gradually increases. When other components are subsequently added, it can produce a certain suspension effect on possible solid particles to prevent them from settling quickly, laying the foundation for the formation of the entire suspension system. At the same time, the polyvinyl alcohol molecular chain contains a large number of hydroxyl groups. During the heating and stirring dissolution process, these hydroxyl groups form hydrogen bonds with water molecules, so that the molecular chains gradually stretch, and the film formed wraps the composition particles or solution droplets, so that they remain relatively stable on the water surface, extending the action time of the composition. The suspension aid mixed solution obtained by mixing the two can ensure that the composition can play a better role during the rice growth cycle, reducing the problem of poor control effect caused by loss or uneven distribution of the composition;

[0046] Sodium dodecyl sulfate in S2 reduces the surface tension, thereby reducing the energy required for the dispersion process of the composition particles in water, covering a larger water surface area in a shorter time, forming a uniform composition layer, and maintaining the stable efficacy of the drug;

[0047] After the potassium humate in S3 is crushed, the particles become smaller and its specific surface area increases significantly, so that it can enhance the adsorption capacity of effective ingredients and other nutrients as a nutrient carrier, thereby carrying and transferring these substances more effectively;

[0048] The mixed solution of suspension aid in S4 has a certain thickening and suspension effect. When thiophanate-methyl, fluopicolide and sodium naphthylacetate are added, these active ingredients can be evenly dispersed in the suspension aid solution under stirring. The suspension aid prevents the rapid sedimentation of the active ingredients, keeps them suspended in the solution, and lays the foundation for the subsequent formation of a uniform composite system. The addition of dispersion aid solution further reduces the surface tension of the system, making the tiny particles in the mixed solution of active ingredients and suspension aid more dispersed, ensuring the uniformity of the composite system. The addition of nutrient carriers and sedimentation aids gives the composite system more functions, and together constructs a multifunctional composite system integrating sterilization, growth regulation, nutrient supply and sedimentation functions.

[0049] The light calcium carbonate in S5 can improve the texture and fluidity of the paste. Before adding light calcium carbonate, the paste may appear too viscous or uneven in texture due to the interaction of various components. The filling effect of light calcium carbonate can make the texture of the paste more uniform and optimize the fluidity, which is very beneficial for subsequent drying and pulverizing operations. The addition of calcium stearate ensures that the composition can remain in a loose state throughout the storage and use process.

[0050] After the previous mixing and processing steps in S6, the final mixture contains a certain amount of water. The main purpose of vacuum drying is to effectively remove this water under low temperature and reduced pressure conditions. At the same time, vacuum drying helps to maintain the physical and chemical properties of the composition. By slowly and steadily removing the water, it can prevent the composition from crusting, agglomeration or migration of active ingredients during the drying process. The dried material usually forms blocks or larger particles. The purpose of the pulverization treatment is to break it into fine and uniform particles. The appropriate particle size has an important influence on the performance of the wettable powder. Smaller particle size can increase the specific surface area of ​​the composition, improve the dissolution rate and dispersibility of the composition in water, and enable the composition to work faster.

[0051] When the polyvinyl alcohol solution in S1 is prepared, the water temperature is controlled at 80-90° C. and the stirring speed is 400-600 rpm.

[0052] Specifically, polyvinyl alcohol is a high molecular polymer. Raising the water temperature to 80-90°C can weaken the hydrogen bonds between molecular chains, intensify molecular motion, and accelerate the dissolution rate of polyvinyl alcohol. At the same time, a stirring speed of 400-600 rpm can generate sufficient shear force to allow the polyvinyl alcohol powder to fully contact with hot water, thereby improving the preparation efficiency.

[0053] In the process of S2, sodium dodecyl sulfate is added in multiple times, with the time interval between each addition being about 1-2 minutes, and the stirring time is continued for 10-20 minutes.

[0054] Specifically, the amount of sodium dodecyl sulfate added each time is relatively small, and the interval time allows the solution to have time to fully mix and react with the newly added sodium dodecyl sulfate, so that the dissolution rate of sodium dodecyl sulfate can be more stably controlled to avoid fluctuations in the solution system caused by an overly rapid dissolution process, such as excessive foaming or excessive changes in the solution temperature.

[0055] The mesh size of the sieve after the potassium humate and attapulgite in S3 are crushed is 80-100 meshes.

[0056] Specifically, after the potassium humate and attapulgite are crushed, they are screened using an 80-100 mesh sieve to ensure that the particle sizes of the potassium humate and attapulgite are within a relatively consistent range, thereby improving the mixing effect.

[0057] The stirring speed during the paste formation process in S4 is 500-700 rpm, and the stirring is continued for 30-60 minutes, and the temperature is controlled at 20-30°C.

[0058] Specifically, a stirring speed of 500-700 rpm can ensure that the effective ingredients are fully dispersed in the suspension aid solution, prevent agglomeration, and achieve uniform mixing. Continuous stirring for 30-60 minutes can allow the ingredients to fully react and fuse to form a stable system structure. Temperature control at 20-30°C helps to maintain the activity and stability of the ingredients and avoid abnormal chemical reactions or changes in physical properties caused by excessively high or low temperatures, thereby working together to achieve uniformity, stability and functionality of the paste, laying the foundation for the subsequent preparation of high-quality compositions for controlling rice sheath blight and ensuring that the compositions achieve the best effect in preventing and controlling diseases and promoting rice growth.

[0059] In S5, the stirring speed of light calcium carbonate and the paste is 200-400 rpm, and the stirring speed of calcium stearate mixing is controlled at 100-300 rpm.

[0060] The temperature of the vacuum drying equipment in S6 is controlled at 60-80°C, the vacuum degree is set at 0.08-0.09MPa, and the drying is completed when the water content is less than 5%. The mesh number of the sieve is 200-325 meshes.

[0061] Specifically, the temperature of the vacuum drying equipment is controlled at 60-80°C and the vacuum degree is set at 0.08-0.09MPa. It can efficiently remove moisture to a moisture content of less than 5% under mild conditions, thereby ensuring the stability of the active ingredients and adjuvants and achieving a good drying effect. The 200-325 mesh screen is used for screening to ensure that the particle size of the material after drying meets the requirements of the wettable powder, improve the dispersibility and solubility of the composition, and ultimately make the product stable and in good state in terms of physical and chemical properties, which is conducive to storage, transportation and use, and effectively improves the prevention and control effect of rice sheath blight and the convenience of use.

[0062] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A composition for controlling rice sheath blight, characterized in that: The invention comprises the following raw materials in parts by weight: 5-15 parts of thiofuranamide, 3-10 parts of fluopicolide, 0.01-0.1 parts of sodium naphthylacetate, 1.5-5 parts of a suspension aid, 2-5 parts of a dispersion aid, 8-15 parts of a nutrient carrier and a sedimentation aid, 10-20 parts of a filler and 0.1-0.5 parts of an anti-caking agent.

2. A composition for controlling rice sheath blight according to claim 1, characterized in that: The suspension aid includes sodium carboxymethyl cellulose and polyvinyl alcohol, the sodium carboxymethyl cellulose is 1-3 parts, the polyvinyl alcohol is 0.5-2 parts, the dispersing aid is sodium dodecyl sulfate, the nutrient carrier and sedimentation aid include potassium humate and attapulgite, the potassium humate is 5-10 parts, and the attapulgite is 5-10 parts.

3. A composition for controlling rice sheath blight according to claim 1, characterized in that: The filler is light calcium carbonate, and the anti-caking agent is calcium stearate.

4. A method for preparing a composition for controlling rice sheath blight, according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1. Preparation of suspension aid: Slowly add the weighed sodium carboxymethyl cellulose into deionized water, stirring while adding, until the sodium carboxymethyl cellulose is completely dissolved to form a uniform transparent solution; meanwhile, in another container, add polyvinyl alcohol into water, heat and stir until the polyvinyl alcohol is completely dissolved to obtain a polyvinyl alcohol solution; then mix the two solutions together, stir evenly, and form a suspension aid mixed solution; S2. Preparation of dispersing aid solution: adding sodium dodecyl sulfate into water and stirring to dissolve it to obtain a sodium dodecyl sulfate solution; S3, pretreatment of nutrient carrier and sedimentation aid: potassium humate and attapulgite are crushed separately, screened, and then mixed; S4, mixing and stirring: adding thiofuran, epoxiconazole and sodium naphthylacetate to the suspension aid mixed solution and stirring and mixing, then adding the dispersion aid solution and the mixed nutrient carrier and sedimentation aid to the system and stirring to form a uniform paste; S5, filling and anti-caking treatment: adding light calcium carbonate to the above paste, dispersing it evenly in the system, then adding calcium stearate, and continuing to stir to evenly distribute the calcium stearate to prevent the composition from agglomerating during storage; S6. Post-treatment: drying the final mixture by vacuum drying, and then crushing and sieving the dried material to prepare a wettable powder, thereby obtaining the composition for controlling rice sheath blight.

5. The method for preparing a composition for controlling rice sheath blight according to claim 4, characterized in that: When the polyvinyl alcohol solution in S1 is prepared, the water temperature is controlled at 80-90° C. and the stirring speed is 400-600 rpm.

6. The method for preparing a composition for controlling rice sheath blight according to claim 4, characterized in that: In the process of S2, sodium dodecyl sulfate is added in multiple times, with the time interval between each addition being about 1-2 minutes, and the stirring time is continued for 10-20 minutes.

7. The method for preparing a composition for controlling rice sheath blight according to claim 4, characterized in that: The mesh size of the sieve after the potassium humate and attapulgite in the S3 are crushed is 80-100 meshes.

8. The method for preparing a composition for controlling rice sheath blight according to claim 4, characterized in that: The stirring speed during the paste formation process in S4 is 500-700 rpm, and the stirring is continued for 30-60 minutes, and the temperature is controlled at 20-30°C.

9. The method for preparing a composition for controlling rice sheath blight according to claim 4, characterized in that: The stirring speed of the light calcium carbonate and the paste in S5 is 200-400 rpm, and the stirring speed of the calcium stearate mixing is controlled at 100-300 rpm.

10. The method for preparing a composition for controlling rice sheath blight according to claim 4, characterized in that: The temperature of the vacuum drying equipment in S6 is controlled at 60-80°C, the vacuum degree is set at 0.08-0.09MPa, and the drying is completed when the water content is less than 5%. The mesh number of the sieve is 200-325 meshes.

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