Binary nano-suspension co-formulated with ester-type fungicide

Abstract

The present invention relates to the field of nanopesticides, and relates to a mancozeb compounded nanosuspension having a particle size less than 100 nanometers and a preparation method therefor. According to the present invention, two or three components are diluted and mixed with water to form a mancozeb compounded nano-suspension below 100 nanometers. The preparation method comprises: when the stirring speed is not less than an effective stirring speed, adding a component I diluent into a component II diluent, or adding the component II diluent into the component I diluent; and forming a mancozeb compounded nanosuspension.

Description

18 07 25 [Technical Field] The present invention belongs to the field of nano-pesticides and particularly relates to the preparation of a binary co-formulated nano-suspension with particle sizes smaller than 100 nanometers. [Background Art] Nano-pesticides refer to pesticide formulations in which the particle size of tire active ingredient is at the nanometer scale. From the perspectives of application efficacy and formulation stability, it is preferable for nano-pesticide particles to be below 100 nm, and the smaller the better. Currently, the particle size of mainstream pesticide formulations remains at the micrometer level, typically several micrometers or more. If particle size could be reduced to the nanometer scale - a 1000-fold reduction -then, under the premise of maintaining the particle form, the number of particles of the same mass of active ingredient would theoretically increase by a factor of one billion, and the total surface area by a factor of one thousand. The significant increase in both particle number and surface area would allow for more uniform dispersion of the pesticide and broader contact with target pathogens, thereby enhancing and maximizing efficacy. This is the fundamental reason driving the development of nanopesticides. Mancozeb has been in use internationally for over fifty years and has consistently ranked among high-tonnage pesticide products. It is a highly effective protective organic sulfur fungicide. Its notable characteristics include low toxicity, long residual effect, broad-spectrum activity against multiple groups of pathogens, and a low risk of resistance development. As such, it is widely valued. Mancozeb is a broad-spectrum, non-systemic fungicide with protective properties. It is used on a variety of crops including fruit trees, vegetables, ornamental plants, and tobacco. It is effective against numerous major foliar fungal diseases. Examples include early and late blight in potatoes and tomatoes; downy mildew and black rot in grapes; net blotch, stripe disease, and large spot disease in wheat and com; as well as damping-off, seedling blight, downy mildew, anthracnose, and phytophthora in cotton, peanuts, and vegetables. Mancozeb is compatible with many other pesticides, allowing the development of multiple coformulated products. However, whether used alone or in combination, its physical properties—being insoluble in both water and organic solvents—limit its formulations to traditional types such as powders, wettable powders, water-dispersible granules, and suspension concentrates. Based on current pesticide formulation technology, tire smallest particle size achievable for mancozeb-based products is typically several microns and often reaches tens of microns. Such large particle sizes hinder efficacy. Additionally, due to long-term widespread use and some degree of resistance development, current application rates per hectare are high—typically 750 to 2250 grams of active ingredient per hectare. Thus, improving its efficacy and reducing its dosage per area has become a key focus in formulation research. It must be clarified that the preparation of existing mancozeb formulations is based on the prior synthesis of mancozeb technical material, followed by formulation processing. The steps include: (1) Synthesis of technical material: This consists of two stages. The first is synthesizing water-soluble mancozeb-ammonium or mancozeb-sodium. Tire second is forming mancozeb by reacting these with manganese and zinc salts through salt formation and complexation, resulting in a precipitated solid product. This precipitate is insoluble in both water and organic solvents and must be filtered, washed, and dried to yield mancozeb technical material. 18 07 25 (2) Formulation processing: The solid mancozeb technical material is used to produce the desired formulation through processes such as pulverizing, grinding, and mixing. These steps—beginning with water-soluble mancozeb-ammonium or mancozeb-sodium and ending with the production of various solid formulations—require significant processing infrastructure and energy consumption, including filtration, drying, pulverization, grinding, and mixing equipment, along with appropriate manufacturing workflows and facilities. The traditional process for preparing mancozeb technical material and producing common powder or wettable powder formulations is illustrated in Figure 1. Prior Art: A technical solution for preparing nano-sized mancozeb using conventional mancozeb technical material. Chinese Patent CN201711490378.4 discloses a nano-sized mancozeb powder formulation. However, the disclosed solution does not produce truly nano-sized mancozeb, particularly not with particle sizes below 100 nm. It must be emphasized that in a true nano-suspension system, adding a water-soluble polymer as a dispersant should yield a transparent solution. In contrast, the water dispersion of the filter cake in this prior art appears as a “turbid suspension,” indicating that it does not achieve a true nanosuspension, especially not with particle sizes under 100 nm. The comparative technology (CN201711490378.4) claims to produce nano-sized mancozeb during synthesis by adding a dispersant and a buffer. However, scientific analysis reveals flaws in the choice of dispersant, and the use of acidic buffer neutralizes its intended effect. Experimental results from the present invention show that nano-sized mancozeb particles only form under conditions of extremely low concentration. Thus, it is believed that the comparative technology cannot feasibly achieve industrial-scale production of “nano mancozeb.” Given that currently registered mancozeb products by both domestic and international pesticide companies in China have particle sizes in the micron range, and considering the limitations of the aforementioned “nano mancozeb” technology, it is evident that the development of truly nano-sized mancozeb (especially under 100 nm) presents significant technical challenges. This underscores the need for innovative thinking and alternative approaches to achieve a mancozeb nano-suspension. [Summary of the Invention! Prior applications: PCT / CN2022 / 139831; PCT / CN2022 / 139832; PCT / CN2022 / 139833 One of the objectives of the present invention is to overcome the shortcomings of the prior art and to provide a novel concept and method, distinct from the traditional approach of preparing mancozeb powder formulations. Through a water-dilution process, a reaction between mancozeb-ammonium (or mancozeb-sodium, mancozeb-potassium) and manganese and zinc salts is achieved, forming mancozeb in situ. This enables the preparation of a nano-suspension of mancozeb that appears water-soluble and transparent in appearance, and can be used directly for spraying. The mancozeb nano-suspension described in this invention can be loaded into agricultural spraying equipment for direct application. The innovative concept of this invention is as follows: Mancozeb-ammonium is a water-soluble ammonium salt that disperses as single molecules in water, serving as one component. The reacting manganese and zinc salts also disperse in water as individual 18 07 25 molecules and metal ions, forming the other component. Upon mixing, ionic reactions readily occur to form mancozeb structures with manganese and zinc. Since manganese and zinc ions are multivalent metal ions, they may form not only salts but also complex compounds. Whether through salt formation or complexation, nano-sized mancozeb crystals can be produced during the mixing process by controlling the addition of one component. Under controlled stirring speed, one component (e.g., manganese and zinc salt solution) is added to the aqueous solution of the other component (e.g., mancozeb-ammonium). By regulating both the dropwise addition rate and the stirring speed, nanocrystals of mancozeb and their corresponding nano-suspension can be generated. When the resulting nanocrystals of mancozeb are sufficiently small and fewer in number, they can remain temporarily and stably dispersed in the aqueous system. However, as more nano-crystals form, collisions, growth, and aggregation between the particles may occur. When their size approaches the wavelength of visible light, tire system starts to exhibit opalescence; once exceeded, it gradually turns turbid. Due to gravitational effects, larger particles tend to precipitate. To prevent this, a polymeric adjuvant must be added to the system. These are water-soluble polymers that generally exist in water as amorphous polymer coils. These coils spontaneously form loose spherical structures, with hydrophobic main chains aggregated inside and polar hydrophilic groups outside. At this stage, mancozeb nanocrystals with particle sizes below 100 nm, driven by mechanical stirring and shear force, diffuse into and are encapsulated by these random coils. This effectively isolates the crystals and prevents further collisions, growth, precipitation, and aggregation. Thus, the random coils formed by the water-soluble polymeric adjuvants serve to disperse, suspend, stabilize, and protect the mancozeb nanocrystals. Tire coils are evenly dispersed in the aqueous phase, and so are the nanocrystals embedded within them. When the crystal size is below 100 nm, the system becomes clear and transparent, with apparent water solubility', and may exhibit the “Tyndall effect.” It should be noted that during the formation of nanocrystals, the component addition speed and the system's stirring rate are critical factors determining particle size. These parameters affect the amount of material added per unit time and the uniformity of dispersion—both are crucial in achieving nanoscale particles. For the addition speed, if particle size below 100 nm is the goal, the transparency of the system becomes the judgment criterion. The theoretical basis lies in the fact that when particle size is less than one-quarter of the lower limit of the visible light wavelength range (400^760 nm), no significant refraction or reflection occurs, and the system remains transparent. Conversely, if the system becomes opalescent or turbid, it indicates that the particles exceed 100 nm in size. To achieve this, the following points must be observed: (T) the mixing rate of the two component solutions (i.e., the addition rate of one component) must not be too fast. Excessive addition speed results in uneven dispersion and localized high concentrations, accelerating the formation rate and quantity of crystals, which may lead to aggregation and increased particle size. If opalescence appears, it indicates particles have reached several hundred nanometers. Therefore, the addition rate must be controlled to ensure the system remains transparent throughout. @ the stirring speed of the system should be moderately increased. Stirring speed affects both the formation and dispersion rate of nanocrystals in tire aqueous phase. Adequate stirring promotes rapid formation and dispersion of nanocrystals, helps maintain small particle sizes, and prevents aggregation. Stirring speed should be coordinated with the component addition rate to ensure the system always remains transparent. [Terminology Explanation! 18 07 25 Tyndall Effect: The so-called Tyndall effect refers to the phenomenon where, when a beam of light passes through a colloid, a bright "pathway" of light can be observed from a direction perpendicular to the incident light. This phenomenon, also known as the Tyndall phenomenon, is essentially a type of light scattering that occurs as light propagates through a colloidal system. The Tyndall effect occurs because colloidal particles generally have diameters in the range of 1 to 100 nm, and thus visibly scatter light. In contrast, true solutions exhibit negligible light scattering. Therefore, the Tyndall effect is a key indicator used to distinguish colloidal solutions from true solutions. When the particle size is smaller than the wavelength of the incident light, the light is scattered — the wave bends around the particles and radiates in all directions, producing what is referred to as scattered light or opalescence. The Tyndall effect is fundamentally a manifestation of light scattering or opalescence. The scattering intensity increases with the concentration of particles in the dispersed system. Consequently, when a solution appears clear and transparent, it suggests that the particle size is less than 100 nm and the Tyndall effect may be observed. If the particles are larger than the wavelength of incident light (400-740 nm), strong reflection occurs. In this case, the solution appears increasingly milky or turbid and may even become opaque, indicating particle sizes approaching the micron level or higher. System: In the context of this invention, a "system" refers to the suspension formed when two components are mixed under controlled addition and stirring conditions during the preparation of the mancozeb nano-suspension. The system comprises a mixture of water, precursors, manganese and zinc salts, and water-soluble polymeric adjuvants that together yield the target product — the nanosuspension. Component: "Component" refers to a composition comprising one or more ingredients. In principle, any raw material used m this invention may independently form a component. However, to facilitate packaging, transportation, and use, simplification and grouping of ingredients are preferred. The grouping principle is: (T) no chemical reaction should occur between ingredients in the same component; @ the total number of components should not be excessive. Ingredient: "Ingredient" refers to the raw materials used in this invention, including water-soluble dithiocarbamate salts, manganese salts, zinc salts, water-soluble polymeric adjuvants, and water. Precursor: "Precursor" refers to the parent material used in the synthesis of the target product, mancozeb. Specifically, it refers to water-soluble dithiocarbamate salts, including mancozeb-ammonium, mancozeb-sodium, and mancozeb-potassium. Water-Soluble Polymeric Adjuvant: This refers to a polymer containing hydrophilic polar groups that can dissolve in water. It is also known as a polymeric surfactant or active agent. These adjuvants provide dispersion, suspension, emulsification, and stabilization functions. Based on their ionic nature, they can be classified into anionic, cationic, amphoteric, and nonionic polymeric adjuvants. Particle Size: Also referred to as particle diameter, this term describes the size of mancozeb crystal particles formed in the system through interactions between the precursor and zinc / manganese salts, under the dispersive action of water-soluble polymeric adjuvants. It also encompasses the particle sizes of other co-fonnulated pesticide active ingredients and does not exclusively refer to crystalline morphology. Sub-100-iim Grade: This is a statistical classification referring to the particle size distribution of pesticide particles in the system. A "sub-100-nm grade nano-suspension" in this invention refers to suspensions where the peak of the particle size distribution (in terms of mass fraction across each size 18 07 25 range) is below 100 nm. Measurement can be conducted using a Malvern laser nanoparticle size analyzer from the UK, processed using the Number statistical method. Stability Period: This refers to the duration during which the nano-suspension remains transparent after preparation. To ensure that spraying operations can be completed, the stability period should be no less than 1 hour. The "hour-level stability period" proposed in this invention refers to a time span of 1 to 5 hours. Effective Stirring Speed: This term denotes the minimum stirring speed required — under a given addition method — to allow one component to be adequately dispersed in another upon addition, ensuring that the resulting nanocrystals are evenly dispersed, avoiding crystal growth and aggregation, and maintaining particle size below several hundred nanometers. Transparency of the resulting liquid indicates effective stirring. Effective Stirring: The method and speed of stirring during addition significantly affect the final suspension. Stirring methods may include mechanical stirring, multi-point mechanical stirring, manual stirring, and multi-point manual stirring. Faster stirring generally yields better results. If the resulting liquid is transparent, it is considered effective stirring; otherwise, it is considered ineffective. Addition Method: This refers to how the components are introduced into the system — e.g., Component A into Component B, Component B into Component A, or both components simultaneously into the system. Methods include continuous addition, intermittent addition, fine stream addition, dropwise addition, spray addition, and addition at fixed or moving positions. The method should facilitate rapid mixing and dispersion. Addition Speed: Once the method of addition is determined, the speed must be controlled to achieve effective stirring and dispersion of components. Nano-Emulsion: Also called nano-emulsified formulation, this refers to a dispersed system in which a pesticide active ingredient forms a solution that is dispersed in water with the help of adjuvants, resulting in nano-sized emulsified particles. These emulsions appear clear and transparent, typically with particle sizes below 100 nm, and possess thermodynamic stability. Ester-Type Fungicide Nano-Emulsion: This refers to nano-emulsions of methoxy acrylate fungicides, including the following single-agent nano-emulsions: Azoxystrobin nano-emulsion Pyraclostrobin nano-emulsion Kresoxim-methyl nano-emulsion Enestroburin nano-emulsion Picoxystrobin nano-emulsion Combination of Mancozeb with Methoxyacrylate Fungicides (Pyraclostrobin, Azoxystrobin, Kresoxim-methyl, Enestroburin, or Picoxystrobin) Mancozeb is a broad-spectrum, multi-site protective fungicide. Its primary function is to prevent fungal diseases. For optimal efficacy, it should be applied preventively and preferably in combination with other fungicides, especially systemic ones. Therefore, to enhance control of crop diseases, mancozeb is often co-formulated with other fungicides. 18 07 25 To achieve excellent target control in a single plant protection operation, this invention proposes — based on the established technology for mancozeb nano-suspensions — further development of binary nano-suspensions co-formulated with different fungicides. The methods and formulations proposed in this invention aim to broaden the application scope of mancozeb nano-suspensions. Methoxyacrylate Fungicides are anew class of fungicides derived from the natural antibiotic Strobilurin A. The first commercial methoxyacrylate fungicide — azoxystrobin — was developed by ICI (now Syngenta). Subsequently, other products such as pyraclostrobin, kresoxim-methyl, enestroburin, and picoxystrobin were introduced. After years of development, a total of 13 methoxy aery late fungicides have been commercialized. Among them, azoxystrobin holds the largest market presence, followed by pyraclostrobin and kresoxim-methyl. Pyraclostrobin lias the molecular formula C19H18CIN3O4 and the chemical name methyl N-methoxycarbamoyl-N-[2-[l-(4-chlorophenyl)-pyrazol-3-ylmethoxy] phenyl] carbamate. It is abroad-spectrum fungicide belonging to the methoxyacrylate class, primarily used to control a wide variety of fungal diseases in crops. By inhibiting mitochondrial respiration, it ultimately leads to cell death. It exhibits protective, curative, and translammar activity. Pyraclostrobin is characterized by broad-spectrum efficacy, high efficiency, low toxicity, lack of odor, low resistance development potential, crop growth promotion, and enhanced stress resistance in plants. Its performance surpasses that of earlier fungicides such as azoxystrobin and kresoxim-methyl. It is especially effective against wheat powdery mildew and Fusarium head blight. Beyond its direct antifungal activity, pyraclostrobin also induces physiological effects in crops, particularly cereals—such as enhanced nitrogen uptake—which promote rapid growth and increase yields. Pyraclostrobin has therefore gained wide application in global agriculture. Azoxystrobin, chemically named (E)-2-(2-[6-(2-cyanophenoxy) pyrimidin-4-yloxy] phenyl} -3-methoxyacrylate, with molecular formula C22H17N3O5, inhibits mitochondrial respiration by blocking electron transfer from cytochrome bl to cytochrome cl, disrupting spore germination and hyphal growth, ultimately inhibiting sporulation and causing cell death. It is effective against fungal strains resistant to demethylation inhibitors (DMIs), benzamides, dicarboximides, and benzimidazoles. Azoxystrobin has systemic, broad-spectrum, and highly effective activity. It provides protective, curative, and eradicative effects against almost all fungal pathogens and has no cross-resistance with other fungicides. It is effective in controlling powdery' mildew, rust, sheath blight, leaf spots, and net blotch in soybeans, grains, fruits and vegetables, rice, maize, potatoes, rapeseed, cotton, grapes, and other crops. Trifloxystrobin, chemically named (2Z)-2-methoxyimino-2-[2-[[l-[3-(trifluoromethyl) phenyl] ethylideneamino] oxymethyl] phenyl] acetic acid methyl ester, with the formula C20H19F3N2O4, exhibits high efficiency, broad spectrum, protective, curative, eradicative, translaminar, and systemic activity. It is rainfast, has long-lasting effects, and is effective against pathogens resistant to DMIs, benzamides, dicarboximides, and benzimidazoles. It does not exhibit cross-resistance with existing fungicides. Trifloxystrobin shows excellent efficacy against virtually all fungal classes (Ascomycota, Basidiomycota, Oomycetes, and Deuteromycetes), such as powdery' mildew, rust, sheath blight, leaf spots, downy mildew, rice blast, and damping-off. It is particularly effective against powdery' mildew and also effective against rust, downy mildeyv, apple scab, and sclerotinia in rapeseed. Trifloxystrobin is safe for crops and environmentally friendly due to its rapid degradation in soil and water. Its broadspectrum activity, fast absorption, and upward systemic mobility give it excellent rainfastness and persistence, earning it the label of a “second-generation methoxyacrylate fungicide.” Picoxystrobin, chemically named (E)-3-methoxy-2-{2-[6-(trifluoromethyl)-2-pyridyloxymethyl] phenyl} acrylate, with molecular formula CAHisBNCk is a systemic fungicide with broad-spectrum antifungal activity and high crop safety. During the growing period of cereals, it helps maintain leaf integrity without disease symptoms. It is mainly used to control foliar diseases in wheat and other cereals, such as leaf blight, leaf rust, glume blotch, brown spot, and powdery mildew. It shows strong therapeutic effects against wheat leaf blotch, net blotch, and stripe disease. 18 07 25 Binary formulations of mancozeb and methoxyacrylate fungicides (pyraclostrobin, azoxystrobin, kresoxim-methyl, trifloxystrobin, or picoxystrobin), when mixed in appropriate ratios, yield broadspectrum, low-toxicity composite fungicides with both protective and curative functions. The two distinct modes of action reduce the likelihood of resistance development. These combinations are safe and easy to use, with extended persistence. Mancozeb / methoxyacrylate composite formulations (eg., mancozeb / pyraclostrobin or mancozeb / azoxystrobm. etc.) are suitable for a wide range of crops and are effective against many advanced fungal diseases, particularly scab, powdery mildew, and leaf spot diseases. Currently, they are used to control: Apple altemaria leaf spot, Banana leaf spot and scab, Citrus scab, greasy spot, and anthracnose, Melon downy mildew, Strawberry leaf spot and anthracnose, Cowpea rust, etc. The mancozeb / pyraclostrobin formulations vary in spray water volume depending on crop and target disease, with current active ingredient ratios typically in the range of 50-160 / 5-20. The main formulation types include suspension concentrates (SC), wettable powders (WP), water-dispersible granules (WDG), and dispersible oil suspensions (OD). The nano-suspension of mancozeb and methoxyacrylate fungicides (pyraclostrobin, azoxystrobin, kresoxim-methyl, trifloxystrobin, or picoxystrobin) described in this invention refers to a nanosuspension with particle sizes below 100 nanometers. The sub-100-nanometer nano-suspension is formed by diluting and mixing at least two components with water. Mancozeb / Methoxyacrylate Fungicide Nano-suspension Hie prior application (PCT / CN2022 / 139831) has described the formation mechanism of mancozeb nano-suspension. Building on that foundation, this invention introduces the addition of methoxyacrylate fungicides (pyraclostrobin, azoxystrobin, kresoxim-methyl, trifloxystrobin, or picoxystrobin) to further develop a binary pesticide nano-suspension. The methoxyacrylate fungicide (pyraclostrobin, azoxystrobin, kresoxim-methyl, trifloxystrobin, or picoxystrobin) is incorporated into Component A in the form of a nano-emulsion. Upon mixing of the two components under specified conditions, the physical state of the methoxyacrylate fungicide particles depends on the dilution water volume and the concentration of polymeric adjuvants in the system. When the amount of water is relatively low, the concentration of the diluted polymeric adjuvant remains sufficient to sustain the presence of nano-micelles. In this case, mancozeb nanocrystals coexist with methoxyacrylate nano-emulsion particles. However, if the volume of water added exceeds the threshold required to maintain the minimum concentration of polymeric adjuvants necessary for nano-micelle stability, the micelles disintegrate, and the methoxyacrylate fungicide precipitates in the form of nanocrystals. The result is a nano-suspension containing a mixture of nanocrystals of both active ingredients. The binary' component formulation is as follows: Component A: A water-soluble dithiocarbamate salt or its aqueous solution, a water-soluble polymeric adjuvant, and water. The water-soluble dithiocarbamate salt is selected from mancozeb-ammonium, mancozeb-sodium, or mancozeb-potassium, or a mixture of at least two thereof. The water-soluble polymeric adjuvant consists of at least one nonionic surfactant, either as a composite adjuvant or in aqueous solution. Additionally, Component A includes a nano-emulsion of a methoxyacrylate fungicide (pyraclostrobin, azoxystrobin, kresoxim-methyl, trifloxystrobin, or picoxystrobin). Component B: A mixture of manganese salt and zinc salt in a specified ratio. Each of the manganese and zinc salts comprises at least one type of salt. 18 07 25 Component B may be a solid mixture of manganese and zinc salts, or it may be dissolved in water to form an aqueous solution. It may also include added water-soluble polymeric adjuvants. The water-soluble polymeric adjuvant is selected from at least one nonionic surfactant. The manganese salt is selected from at least one of the following: manganese sulfate, manganese acetate, manganese chloride, manganese nitrate. The zinc salt is selected from at least one of the following: zinc sulfate, zinc acetate, zinc chloride, zinc nitrate. The amount of water-soluble polymeric adjuvant refers to the combined quantity in both Component A and Component B. Its ratio to the total amount of dilution water should not exceed 1:1500. The dilution water includes all water present in the system. Suitable nonionic surfactants include: Water-soluble starch and its derivatives, Water-soluble guar gum and its derivatives, Polyoxypropylene-polyoxyethylene block copolymers, fatty alcohol polyoxyethylene ethers, fatty acid polyoxyethylene ethers, fattv amine polyoxyethylene ethers, alkylaryl polyoxypropylene-polyoxyethylene ethers, arylphenol polyoxyethylene ethers, castor oil polyoxyethylene ethers, alkyl polyglycosides, tween, polyvinyl alcohol, polyvinylpyrrolidone, etc. Among these, degradation products of nonylphenol polyoxyethylene ether are known to have feminizing toxicity and should be excluded. Preferred surfactants include: polyoxypropylene-polyoxyethylene block copolymers, fatty alcohol polyoxyethylene ethers, fatty acid polyoxyethylene ethers, fatty amine polyoxyethylene ethers, alkylaryl polyoxypropylene-polyoxyethylene ethers, castor oil polyoxyethylene ethers, alkyl polyglycosides, and Tween. Furthermore, the sub-100-nanometer mancozeb nano-suspension described herein exhibits an hourlevel stability period. When mancozeb salt, manganese salt, and zinc salt are mancozeb-ammonium, manganese sulfate, and zinc sulfate respectively, the mass ratio range is: Mancozeb-ammonium: manganese sulfate: zinc sulfate = 90 : 35-55 : 6-17 Preferably: 90 : 41-45 : 7-9 More preferably: 90 : 41 :7 When the mass ratio of mancozeb-ammonium (for generating 100 parts of mancozeb) : manganese sulfate : zinc sulfate = 90 : 41 : 7, a small amount of polymeric adjuvant may be added to the aqueous Component B (containing the minimum possible water for salt dissolution) without causing turbidity. The adjuvant content should typically not exceed 5%. Stability Period The mancozeb / strobilurin-type fungicide (pyraclostrobin, azoxystrobin, kresoxim-methyl, trifloxystrobin, or picoxystrobin) nanosuspension prepared in the present invention is a type of transparent, apparently water-soluble solution, but it is not a thermodynamically stable system. Therefore, the period during which the nanosuspension maintains a transparent appearance is not indefinite; rather, it lias a defined stability period. From the perspective of spray application operations, once the nanosuspension is prepared, the required operating time should be at least one hour. Thus, the length of the stability period can be described in terms of hours. Accordingly, the invention introduces the concept of a “stability period” for sub-100 nm nanosuspensions. Specifically, the sub-100 nm nanosuspension prepared according to the invention 18 07 25 should maintain its transparent state throughout the spraying process, and its stability period should be at least one hour. From a practical standpoint, the stability period can be further categorized into four time ranges: • Less than 1 hour • 1-2 hours • 2-5 hours • More than 5 hours During the stability period, the nanoscale suspension retains its transparent state, indicating that the particle size remains below 100 nm. Hour-Level Stability Period From the perspective of spray application operations: • A stability time of approximately 1 hour offers limited time for operation. • A stability period exceeding 5 hours is difficult to achieve in binary co-formulated nanosuspensions. • A stability time of 2-5 hours is sufficient to allow most pesticide spraying operations to be completed smoothly. The "hour-level stability period" as defined in this invention refers to a transparent state maintained for 1-5 hours. The hour-level stability period can be further subdivided: • 1-2 hours: Basic operating period — under most circumstances, spraying equipment can complete the operation. • 2-5 hours: Extended operating period — allows for delayed operations or unforeseen situations during spraying. Composition and Additives of Mancozeb I Strobilurin-type Fungicide Nano-suspension Traditional mancozeb pesticide formulations, such as water-dispersible granules or suspensions, typically consist of a single component and are ready for spraying upon dilution with water. However, the pesticide particle sizes in such formulations are generally larger than the micron scale. To obtain a nano-scale suspension, the present invention adopts a multi-component system, where at least two components are diluted and mixed under specific procedures, yielding a mancozeb / strobilurin-type fungicide nano-suspension with particle sizes below 100 nanometers. Two-component Scheme The <100 nm mancozeb nano-suspension with hour-level stability is generated through the reaction of two components: Component A: A transparent aqueous solution composed of mancozeb precursors (ammonium mancozeb, sodium mancozeb, or potassium mancozeb), nano-emulsion of pyraclostrobin (or azoxystrobin, kresoxim-methyl, trifloxystrobin, or picoxystrobin). and water. The core constituents of Component A are the mancozeb precursor, water-soluble polymer surfactants providing dispersion, suspension, and stabilization, and water. Nano-emulsions of active ingredients may be added on this basis. Within Component A, the strobilurin-type fungicide nano-emulsion includes a certain amount of water-soluble polymeric additive. Additional water-soluble polymer additives may be introduced as needed. Component B: A mixture composed of inorganic manganese salts and zinc salts in a defined ratio. This component exists m three forms: o Solid-state inorganic manganese and zinc salts (Component Bl) o Aqueous solution of inorganic manganese and zinc salts (Component B2) 18 07 25 o Aqueous solution of inorganic manganese and zinc salts with water-soluble polymer additives (Component B3) The manganese salt is selected from at least one of manganese sulfate, manganese acetate, manganese chloride, or manganese nitrate. The zinc salt is selected from at least one of zinc sulfate, zinc acetate, zinc chloride, or zinc nitrate. Due to the limited solubility of inorganic manganese and zinc salts in water, the volume of Component B must be minimized by limiting water usage. Furthermore, the solubility of these inorganic salts is influenced by the amount of additives, which in turn constrains the amount of water-soluble polymer additives that can be added to Component B. Component B3 is an improved formulation where the water-soluble polymer additive is distributed between both Component A and Component B. Considering the inherent limitations of Component B, the proportion of polymer additives in Component B must be capped, unless one disregards the volume constraints of Component B entirely. Component Ratio Design for Mancozeb / Strobilurin-type Fungicide (Pyraclostrobin, Azoxystrobin, Kresoxim-methyl, Trifloxystrobin, or Picoxystrobin) Nano-suspension The two-component formulation includes two active ingredients: mancozeb and a strobilurin-type fungicide (pyraclostrobin, azoxystrobin, kresoxim-methyl, trifloxystrobin, or picoxystrobin). Component A: Contains ammonium mancozeb (or sodium mancozeb, potassium mancozeb), or an aqueous solution of at least two of them; and a nano-emulsion of a strobilurin-type fungicide (such as pyraclostrobin, azoxystrobin, etc.). Additional adjuvants may be added if necessary. Component B: Composed of manganese sulfate (or manganese acetate, manganese chloride, manganese nitrate) and zinc sulfate (or zinc acetate, zinc chloride, zinc nitrate) dissolved in water at a defined ratio; adjuvants may also be added. The amounts of active ingredients in Component A and Component B determine the overall formulation. In particular, the quantity of ammonium mancozeb (or sodium or potassium equivalents) in Component A serves as the precursor for generating nanoscale mancozeb and determines the required quantities in Component B. As an example, if spraying 1 / 15 hectare requires 100 grams of mancozeb and 10 grams of pyraclostrobin, the goal is to generate 110 grams of sub-100 nm mancozeb / pyraclostrobin nano-suspension. Alternatively, for 60 grams of mancozeb and 6 grams of pyraclostrobin, the goal is to prepare 66 grams of nano-suspension. Component A uses approximately 90 grams of ammonium mancozeb as the precursor; 100 grams of 10% pyraclostrobin nano-emulsion (containing a certain amount of adjuvants); or approximately 56 grams of ammonium mancozeb and 100 grams of 6% nano-emulsion (also containing adjuvants). Based on the adjuvant distribution principle between Component A and Component B, the majority of adjuvants are assigned to Component A. If both Component A and B are packaged at 500 grams each, the amount of water is calculated by subtracting the weights of ammonium mancozeb, nano-emulsified pyraclostrobin, and polymer adjuvants. Component B is first calculated based on the required amounts of inorganic manganese and zinc salts to react with ammonium mancozeb. Manganese sulfate and zinc sulfate are preferred. It is generally assumed that manganese ions react with ammonium to form mancozeb by replacing ammonium ions and forming cyclic or linear polymer structures, while zinc ions complex with sulfur atoms on the mancozeb molecule to form a coordination structure. 18 07 25 There is no strict stoichiometric ratio between ammonium mancozeb, manganese ions, and zinc ions. In industrial practice, excess reagents are used to ensure complete reactions, representing the theoretical upper limit. This invention adopts lower ratios for the following reasons: (1) High concentrations of manganese and zinc ions are not conducive to the formation and stability of small nano-crystals; (2) Even if the reaction is incomplete, all components are effective fungicides individually; (3) The preparation of the nano-suspension does not involve industrial steps such as washing, separation, and dlying of mancozeb, so no ingredients are lost. Molecular and Mass Ratios: Theoretical maximum: Ammonium mancozeb : manganese sulfate : zinc sulfate = 1 : 0.8 : 0.15 (molar ratio); 90 : 55 : 17 (mass ratio) Preferred for industrial production: 1 : 0.64 : 0.08 (molar ratio); 90 : 43 : 9 (mass ratio) Most preferred for practical use: 1 : 0.6 : 0.06 (molar ratio); 90 : 41 : 7 (mass ratio) Adjuvant Distribution Between Component A and Component B Adjuvants are primarily allocated in Component A. Component A mainly contains ammonium mancozeb (or sodium mancozeb, potassium mancozeb) and a nano-emulsion of strobilurin-type fungicides (pyraclostrobin, azoxystrobin, kresoxim-methyl, trifloxystrobin, orpicoxystrobin). The reason for separately packaging Component A and Component B is that they will react immediately upon mixing. In the two-component system, if the nano-emulsion of pyraclostrobin (or other listed strobilurins) in Component A already contains adjuvants, additional adjuvants are still required—unless a third independent component containing only adjuvants is added. Tins would, however, complicate the component system and the dilution process. Adding adjuvants to Component A is feasible because ammonium mancozeb and the adjuvants are both water-soluble and mutually miscible, without precipitation or other stability issues. However, due to the high concentration of ammonium mancozeb and adjuvants, and the resulting high viscosity, the mixture is difficult to handle. Therefore, an appropriate amount of water should be added to dissolve and dilute the solution, reduce viscosity, and improve operability. Once this purpose is achieved, the total mass of Component A should be minimized to reduce production, packaging, and transportation costs. Component B mainly comprises a mixture of manganese and zinc salts—either in solid form, aqueous solution, or aqueous solution with polymeric adjuvants. Component B may consist of solid mixtures of manganese and zinc salts. These must be dissolved in water before mixing with Component A. To simplify handling, their aqueous solutions can be used. Since their solability is limited, a relatively large amount of water is required. Depending on the solubility behavior of tire mixed salts, the addition of adjuvants may or may not be necessary'. There are two key considerations for this: 1. If too much adjuvant is added to Component B, the surface of the manganese / zinc / adjuvant / water mixture may form a film, hindering subsequent mixing. 2. If the amount of adjuvant in Component A is sufficient to disperse and suspend the nanocrystals of mancozeb and the strobilurin-type fungicide, then Component B may not require adjuvants. However, considering that these pesticides are mainly used on fruit trees for disease prevention, the spraying water volume is high—often up to 200^300 kg per mu (Chinese land unit). If the amount of adjuvant in Component A is insufficient to support dispersion and suspension of the nanocrystals, appropriate adjuvants should be added to Component B. The condition is that, after the addition of 18 07 25 adjuvants to the mixed aqueous solution of manganese and zinc salts, Component B must remain transparent, and no film formation should occur on the liquid surface. When the mass ratio of ammonium mancozeb : manganese sulfate : zinc sulfate = 100 : 41 : 7, the concentration of adjuvants added to the mixed solution of manganese and zinc salts in Component B should generally not exceed 5%. Although increasing the volume of Component A and Component B can technically resolve the above challenges, it would significantly raise production, packaging, and transport costs. Therefore, under the premise of producing nanoparticles of mancozcb / strobilurin-typc pesticide with the desired efficacy, balancing the quantities of each component and the packaging specifications, while minimizing the use of adjuvants and water, is a key design consideration. Water-Soluble Polymeric Adjuvants (1) Hie water-soluble polymeric adjuvants possessing dispersion and suspension properties are crucial in determining the particle size of the mancozeb / pyraclostrobin (or azoxystrobin, kresoxim-methyl, trifloxystrobin, picoxystrobin) nano-crystals formed during the two-component or three-component dilution mixing process in this invention. These adjuvants also affect whether the resulting nano-crystals can remain stably dispersed and suspended. (2) Water-soluble polymeric adjuvants belong to the category of polymeric surfactants. They have the ability to disperse, suspend, and increase viscosity due to their hydrophobic chain structures and hydrophilic functional groups. These groups—located at terminal or side positions—include hydroxyl, carboxyl, carboxymethyl, sulfonic, sulfuric, phosphoric, amino, and quaternary ammonium groups. Based on origin, they are classified into natural and synthetic polymers; and based on the nature of hydrophilic groups, they are categorized into anionic, cationic, nonionic, and amphoteric types. (3) The principles for selecting water-soluble polymeric adjuvants in this invention are: (T) The adjuvant must stably disperse and suspend the formed pesticide nano-crystals. @ It must not be affected by the reaction between multivalent metal ions and water-soluble mancozeb salts. @ It should be as environmentally friendly as possible. Therefore, nonionic polymeric adjuvants derived from natural substances are preferred. Examples include block copolymers of polyoxypropylene-polyoxyethylene, and polyoxyethylene ethers formed from fatty alcohols, fatty acids, fatty amines, alkylphenols, aiy Iphenols, castor oil bases, and similar hydrophobic moieties. These include the Peregal series, OP series, Tween series, polyol series, ricinoleic acid series, and alkylpolyglycosides. However, polyoxyethylene nonylphenol ethers—which may have feminizing toxicity—should be excluded. (4) Tire mancozeb / pyraclostrobin (or azoxystrobin, kresoxim-methyl, trifloxystrobin, picoxystrobin) nano-suspension described herein is formed during the water dilution mixing process by reacting watersoluble ammonium (or sodium) mancozeb with manganese and zinc salts, while simultaneously generating latex or nanocrystals from the strobilurin-typc fungicide nano-emulsion. For mancozeb / pyraclostrobin nano-suspensions, if the application dosage is 100 g / 8 g per mu, and dilution water is 200 kg / mu (1 mu = 1 / 15 hectare), the concentrations of the two active ingredients are 0.05% / 0.004%, respectively. For mancozeb / trifloxystrobin nano-suspensions, if the application dosage is 100 g / 4 g per mu, and dilution water is 100 kg / mu, the concentrations of the two active ingredients are 0.01% / 0.004%, respectively. 18 07 25 The required amount of polymeric adjuvant is determined by the amount of mancozeb / strobilurin active ingredients and the volume of dilution water. The concentration of polymeric adjuvants should be at least in the range of 0.1% to 0.2%. According to testing, the particle size of mancozeb / pyraclostrobin (or azoxystrobin, kresoxim-methyl, trifloxystrobin, picoxystrobin) nano-suspension ranges from 30 to 70 nm. These nano-suspensions remain stable for 2 to 5 hours without precipitation or sedimentation and can be directly used for spraying operations with a variety of agricultural pesticide application equipment. (5) The mancozeb / strobilurin nano-suspensions mainly contain nano-sized mancozeb particles formed through reactions during dilution mixing. This process eliminates the need for traditional sy nthesis and purification of technical-grade mancozeb from ammonium / sodium mancozeb in pesticide API production. It also bypasses the multi-step physical processing used by pesticide formulation plants to convert mancozeb and other APIs into wettable powders. The method proposed by this invention can be directly applied in agricultural plant protection operations. The process is energy-saving, environmentally friendly, significantly reduces production costs, and produces nano-dispersions of mancozeb with particle sizes below 100 nm. These small-sized nano-particles greatly enhance efficacy, significantly reduce pesticide dosage, and play a role in improving efficiency and reducing input in agricultural production. A flow diagram illustrating the water-dilution-based preparation process for mancozeb / pyraclostrobin (or azoxystrobin, kresoxim-methyl, trifloxystrobin, picoxystrobin) nano-suspensions is shown in Figure 2. Key Technical Aspects of the Invention 1. Generation Process of Nano-Suspensions This invention innovatively proposes a new model and method for preparing nano-suspensions of mancozeb—a multivalent metal ion-containing pesticide that is insoluble in water and organic solvents—and for preparing nano-suspensions co-formulated with other fungicides. During the required water dilution process, the precursors of the target product are mixed with corresponding metal salts. By leveraging the fast kinetics of ionic reactions and controlling the mixing and stirring speeds of reactants, nano-suspensions with particle sizes below 100 nm, ready for direct use, are obtained. This method eliminates the need for the active ingredient manufacturer to perform the chemical synthesis and purification of mancozeb from water-soluble mancozeb salts and removes the need for pesticide formulation factories to physically process mancozeb and other actives into wettable powders with large particle sizes. This innovative concept, preparation model, and method constitute the core technical breakthrough of this invention. It also applies to the co-formulation of mancozeb with other pesticides into nano-suspensions. 2. Amount of Dilution Water Once the quantities of Components A and B are fixed, the amount of dilution water becomes a key technical parameter for controlling the concentrations of both components and thereby obtaining a stable mancozeb / strobilurin-type fungicide (pyraclostrobin, azoxystrobin, kresoxim-methyl, trifloxystrobin, or picoxystrobin) nano-suspension. The dilution water volume directly affects the concentration of Components A and B in the final mixture. If too little water is used (e.g., 20 kg), the concentration of reactants is high, resulting in rapid formation of nanoparticles but short stability time for maintaining particle sizes below 100 nm. If more than 300 kg of water is used, although a transparent solution may still form, the adjuvant concentration will be significantly diluted, potentially reducing stability—unless more adjuvant is added. Therefore, when both Component A and B are 1000 g each, an optimal dilution range greater than 20 kg but less than 300 kg is critical to ensure proper concentrations and the formation of a stable mancozeb / strobilurin nano-suspension. 18 07 25 3. Type and Amount of Adjuvants Selecting the appropriate type and amount of adjuvant is another critical aspect for forming nanosuspensions of mancozeb and its co-formulated actives. When water-soluble mancozeb salts react with manganese and zinc salts to form nano-sized mancozeb particles, simply using large volumes of water and stirring is insufficient to stabilize particle size. Because these particles are not static—they constantly move and collide—effective collisions result in aggregation, crystal growth, and eventual sedimentation. The only way to prevent particle growth is to choose a suitable type of adjuvant (also known as a dispersant) and determine an appropriate dosage to keep the particles stably dispersed in the aqueous solution formed by the dispersant. Such dispersants must be water-soluble polymers that dissolve in water and exist microscopically as random coils. These coils are significantly larger than the newly formed nanoparticles (usually tens of microns depending on molecular weight and concentration). If the mancozeb and co-formulated active particles are <100 nm, they can diffuse into the coils, where their collisions are blocked or slowed, enhancing stability. This explains the dispersing, suspending, and stabilizing functions of added adjuvants. This invention tested multiple water-soluble polymers. Among numerous anionic, cationic, and nonionic surfactants, only nonionic polymeric adjuvants produced the desired effect. Examples include polyoxyethylene ethers of fatty alcohols, acids, amines; alkylaryl polyoxypropylene-polyoxyethylene ethers; Tween 80; alkylpolyglycosides; polyoxyethylene castor oil, etc. Anionic surfactants tend to react with manganese and zinc ions to form water-insoluble precipitates, losing their dispersing function. However, this invention does not rule out specific combinations of cationic surfactants with appropriate anionic or nonionic surfactants that remain soluble without forming precipitates. The type and amount of water-soluble polymeric adjuvant can be determined through experimentation. The criteria are: • The resulting mancozeb / strobilurin-type fungicide nano-suspension must be visually transparent and apparently water-soluble, ensuring particle sizes below 100 nm. • The stability period of this transparent nano-suspension must fall within 2-5 hours. For the two-component system, the amount of adjuvant can be distributed between Component A and Component B. In principle, if there are no limitations on the volume of the two components, the proportion of adjuvant assigned to Components A and B can be freely adjusted. However, if there are packaging volume constraints for the two components—for example, in the case of pesticide use over 1 / 15 hectare (to generate 100 grams of mancozeb), where each of Component A and Component B is fixed at 1000 grams—then considering that Component B requires more water to dissolve the manganese and zinc salts, and that this inorganic salt solution has lower solubility for the adjuvants, the amount of adjuvant that can be added to Component B becomes significantly limited. Thus, the distribution of adjuvant between the two components can be determined by the following formula: Adjuvant Amount (Component B) = Total Adjuvant Amount - Adjuvant Amount (Component A) -Adjuvant Amount (Nano-emulsion) The amount of adjuvant in this invention is influenced by the amount of dilution water used. When more water is used for dilution, the adjuvant amount should be correspondingly increased. The ratio of adjuvant to dilution water should be at least within 1:1500, preferably within 1:1200, and more preferably within 1:1000. 4. Method of Addition and Stirring The method of addition is also one of the important factors affecting the performance of the mancozeb / strobilurin-type fungicide (pyraclostrobin, azoxystrobin, kresoxim-methyl, trifloxystrobin, 18 07 25 or picoxystrobin) nano-suspension. Once the dilution water volume and the proportions assigned to Components A and B are fixed, the way the components are combined during mixing directly influences the resulting particle size and stability. For example, the addition method raises several key questions: Should the dilution of Component A be added to Component B, or vice versa? How should the addition be carried out? Should it be poured in, trickled in, dropped, or sprayed? Should it be added at a single point or at multiple points? Should it be continuous or intermittent? In practice, once the addition method is chosen, the stirring method must also be considered. Stirring can be manual or mechanical, at a single point or multiple points, and can be continuous or intermittent. The stirring method is closely related to the stirring speed. Regardless of the method of addition or stirring, or the stirring speed, they all fundamentally concern the concentration of reactants in the localized reaction zone created when the two components are mixed, and whether the generated particles can be rapidly dispersed. The most direct way to evaluate whether the addition and stirring method is effective is to observe whether the generated suspension remains transparent. If the nano-suspension is clear and stable over time, it indicates a suitable addition method and that the stirring method and speed are effective. Preparation Method for Mancozeb / Strobilurin-Type Nano-Suspension For the two-component scheme, the invention adopts the following technical solution: Under stirring at a speed not less than the effective stirring speed, either the dilution of Component A is added into the dilution of Component B, or the dilution of Component B is added into the dilution of Component A, to form a nano-suspension of mancozeb / strobilurin-type fungicide (pyraclostrobin, azoxystrobin, kresoxim-methyl, trifloxystrobin, or picoxystrobin). • The dilution of Component A and the dilution of Component B refer to aqueous solutions formed by diluting Components A and B with water. • Component A: consists of water-soluble mancozeb salt or its aqueous solution, and watersoluble polymeric adjuvant; the mancozeb salt includes ammonium mancozeb, sodium mancozeb, or potassium mancozeb, or a mixture of at least two thereof. In addition, Component A contains a nanoemulsion of a strobilurin-type fungicide (pyraclostrobin, azoxystrobin, kresoxim-methyl, trifloxystrobin, or picoxystrobin). • Component B: is a mixture of manganese and zinc salts in a defined ratio, or an aqueous solution thereof. By controlling the method and speed of addition and the stirring speed, nano-crystals of mancozeb / strobilurin with particle sizes around 100 nanometers are formed in the suspension. The final product is thus a nano-suspension of mancozeb / strobilurin with particle sizes below 100 nm. Stirring Methods Manual Stirring: This method is more compatible with most field-use scenarios. Under this condition, the stirring speed must align with physiological limits—it cannot be too fast. Mechanical Stirring: In the field, it is difficult to equip large containers with built-in stirring devices. If such conditions are met, the rotation speed of large mechanical mixers generally does not exceed 100 rpm. Stirring at approximately this speed is sufficient. For manual stirring, the stirring speed should comply with normal human operational capability. To achieve a stable target product, the rate of material addition can be reduced appropriately. The optimal material addition rate should be determined by observing whether the resulting product remains transparent in the system. Addition Method and Addition Speed To ensure that the added material is more evenly and finely dispersed and is rapidly dispersed upon entering the system, one component can be added to the other by continuous addition, batchwise 18 07 25 intermittent addition, or dropwise addition. For the dropwise method, commonly available manual sprayers in rural areas can be used for spray addition, which achieves the best effect. The addition speed should still be determined by observing whether the generated product remains transparent within the system. For current pesticide formulations, water is commonly used as a dispersing medium for spraying. Typically, the pesticide formulation must be diluted with water before spraying or must be mixed with other pesticides for combined use. This process is colloquially known as “tank-mixing.” The present invention utilizes this tank-mixing process to combine Component A and Component B at specific concentrations, addition methods, and speeds, under the action of specific adjuvants (dispersants), to directly obtain a spray-ready transparent nano-suspension of mancozeb / strobilurin fungicide (pyraclostrobin, azoxystrobin, kresoxim-methyl, trifloxystrobin, or picoxystrobin). Amount of Dilution Water Current experimental data show that approximately 50 kg is a reasonable starting point. The amount of dilution water is strongly correlated with the target stability period. Tins is a multivariable issue where the content and composition of the adjuvants in the components are also influential factors. The goal of the invention is to obtain a mancozeb / strobilurin fungicide nano-suspension with a particle size under 100 nm and a transparency stability period of 2 to 5 hours. When the quantity of precursor per unit mass (e.g., 90 g of mancozeb ammonium) and its corresponding metal salts (manganese sulfate, zinc sulfate), as well as the amount of pyraclostrobin (or azoxystrobin, kresoxim-methyl, trifloxystrobin, or picoxystrobin), are fixed, the factors affecting nanoparticle size and stability? include: the amount of dilution water, the amount of adjuvant, and the preparation method. The amount of dilution water affects the size of the nano mancozeb particles and the length of the stability period. Uris is because the volume of water as the dispersing medium affects the concentration of mancozeb ammonium and manganese / zinc sulfate solutions during their moment of contact and reaction, as well as the uniformity of dispersion. These factors influence the size of the generated crystals, dispersion effect, and potential for crystallization and aggregation. The amount of adjuvant used affects the concentration in the aqueous solution and the effectiveness and duration of its dispersing, suspending, and stabilizing function. Too little water will lead to a threshold—for example, at 20 kg dilution water, the transparency stability time of the generated nano mancozeb / strobilurin fungicide suspension is around 1 hour, which is not sufficient for reliable spraying. Therefore, increasing dilution water is necessary?. To produce 100 g of the target product—i.e., a mancozeb suspension with <100 nm particle size and 2-5-hour transparency stability—the preferred dilution water range is between 30-300 kg, yvith 50-200 kg being optimal. Three-Component Basic Scheme The <100 nm mancozeb / strobilurin fungicide (pyraclostrobin, azoxystrobin, kresoxim-methyl, trifloxystrobin, or picoxystrobin) nano-suspension described in the present invention is based on a three-component system, consisting of: Component A': Composed of solid or aqueous solutions of mancozeb ammonium, sodium, or potassium—this serves as the precursor for forming nano mancozeb crystals. Component A' may consist of ammonium mancozeb, sodium mancozeb, potassium mancozeb, or mixtures thereof. Single or mixed substances can be used as solids, allowing for compact packaging and fast dissolution before use. Alternatively, aqueous solutions may be used and diluted directly before use. Water-soluble polymeric adjuvants may or may not be added to Component A'. Component B': Composed of a mixture of manganese and zinc salts in a certain ratio—this provides the multivalent metal ions necessary for forming nano mancozeb cry stals. 18 07 25 Component B' comprises a defined proportion of inorganic manganese and zinc salts. The manganese salt is selected from at least one of manganese sulfate, manganese acetate, manganese chloride, or manganese nitrate; the zinc salt is selected from at least one of zinc sulfate, zinc acetate, zinc chloride, or zinc nitrate. Component B' can be used in solid form for compact packaging or as aqueous solutions for convenience, although their large solution volume may hinder storage and transport. Water-soluble polymeric adjuvants may or may not be added to Component B'. Component C: Nano-emulsion of strobilurin fungicides (pyraclostrobin, azoxystrobin, kresoxim-methyl, trifloxystrobin, or picoxystrobin). The nano-emulsion of strobilurin fungicides is used as Component C and already contains a certain amount of water-soluble polymeric adjuvants. Additional adjuvants may be added to Component C as needed. The total mass of water-soluble polymeric adjuvants required for the three-component scheme is distributed among Component A', Component B', and Component C, including those present in the strobilurin fungicide nano-emulsion. Four-Component Basic Scheme The nano-suspension of mancozeb / strobilurin fungicide (pyraclostrobin, azoxystrobin, kresoxim-methyl, trifloxystrobin, or picoxystrobin) with particle size below 100 nm described in this invention is based on a four-component system composed of: Component A': Composed of solid mancozeb ammonium, sodium, or potassium or their aqueous solutions, serving as the precursor for forming nano mancozeb crystals. Component A' may consist of ammonium mancozeb, sodium mancozeb, potassium mancozeb, or mixtures thereof. These can be used in solid form for easy packaging and minimal volume, dissolving quickly before use, or as aqueous solutions to be diluted to a specific volume before use. Water-soluble polymeric adjuvants may or may not be added to Component A'. Component B, Composed of solid manganese salts or their aqueous solutions in a defined ratio, providing the manganese ions required for forming nano mancozeb crystals. The manganese salt is selected from at least one of manganese sulfate, manganese acetate, manganese chloride, or manganese nitrate. Component Bi can be in solid form (compact packaging) or aqueous solution form (larger volume due to solubility’ limits but convenient for use). A certain amount of watersoluble polymeric adjuvant may also be added. Component Ba. Composed of solid zinc salts or their aqueous solutions in a defined ratio, providing the zinc ions required for forming nano mancozeb crystals. Hie zinc salt is selected from at least one of zinc sulfate, zinc acetate, zinc chloride, or zinc nitrate. Component Blf may be used in solid form (compact packaging) or aqueous solution (convenient but large volume due to solubility limits). Water-soluble polymeric adjuvants may also be added as needed. Component C: Nano-emulsion of strobilurin fungicides (pyraclostrobin, azoxystrobin, kresoxim-methyl, trifloxystrobin, or picoxystrobin) Component C is the nano-emulsion containing tire strobilurin fungicide, which already contains a certain amount of water-soluble polymeric adjuvants. Additional adjuvants may or may not be added based on requirements. The total mass of water-soluble polymeric adjuvants needed for the four-component scheme is distributed among Component A', Component Bi, Component Bii, and Component C, including those already present in the nano-emulsion of Component C. Alternatively, the four components can be categorized as follows: Component A (precursor), Component B (manganese and zinc salts), Component C (nano-emulsion), and Component D (adjuvants). Brief Description of the Drawings Figure 1: Traditional process flow for synthesizing mancozeb technical and formulating wettable powder Figure 2: Schematic diagram for preparing nano mancozeb / strobilurin fungicide suspension (two-component scheme) Figure 3: Schematic diagram for preparing nano mancozeb / strobilurin fungicide suspension (three-component scheme) 18 07 25 Embodiments The method of preparing a nano-suspension of mancozeb / strobilurin fungicide with a particle size below 100 nm and transparency involves the following steps for the two-component scheme: Step 1: Dilute Component A and Component B separately using different volumes of water and dilution ratios to form diluted solutions of Component A and Component B. Step 2: Under mechanical stirring (preferred) or manual stirring at a speed not less than the effective stirring speed, add the diluted solution of Component A uniformly into that of Component B using a specific addition method (e.g., continuous, batch, dropwise, or spraying), or vice versa. For the three-component scheme, the procedure is as follows: Step 1: Dilute Component A' and Component B separately using different volumes of water and dilution ratios to form diluted solutions of Component A' and Component B'. Step 2: Add Component C into the diluted solution of Component A' and stir until evenly dispersed. Step 3: Under mechanical stirring (preferred) or manual stirring at a speed not less than the effective stirring speed, add the diluted mixture of Component A' and Component C uniformly into the diluted solution of Component B' using a defined method (continuous, batch, dropwise, or spraying), or in reverse order. Embodiment 1 The mancozeb / pyraclostrobin nano-suspension is suitable for treating citrus diseases such as scab and anthracnose. The effective ingredient dosage is 100 g / 8 g per mu, with a typical dilution water volume of 200 kilograms per mu. To produce 100 grams of mancozeb, 90 grams of ammonium mancozeb are used. Component Ratios: The ratios of components, dilution water volume, water distribution, addition sequence and method, and test results are presented in the table below: Component Composition (g) Total (g) Dilution Water (kg) Water Distribution Ratio Addition Order Addition Method Result A Ammonium mancozeb: 90 Pyraclostrobin (8%) Nano-emulsion: 100 Additive: 220 Water: 90 500 200 2 / 3 and 1 / 3 AddB dilution into A dilution Continuous dripping Transparent suspension obtained; precipitation observed after 4 hours B Manganese sulfate: 41 Zinc sulfate: 7 Water: 202 250 Additive Used: Fatty alcohol polyoxyethylene ether / Tween-80 / OP-10 (mass ratio 50 / 30 / 20) Operating Method: Component A and Component B were separately diluted using 200 kilograms of dilution water at a 2 / 3 and 1 / 3 ratio, respectively. Under manual stirring, Component B dilution was added into Component A dilution by continuous dripping addition, resulting in a visually transparent mancozeb / pyraclostrobin nano-suspension. Stability lasted for 4 hours. Embodiment 2 18 07 25 The mancozeb / pyraclostrobin nano-suspension is suitable for treating banana leaf spot and black sigatoka. The effective ingredient dosage is 100 g / 24 g per mu, and the typical dilution water volume for spraying on bananas is approximately 300 kilograms per mu. To produce 100 grams of mancozeb, 90 grams of ammonium mancozeb are used. Component Ratios: The ratios of components, dilution water volume, water distribution, addition sequence and method, and test results are presented in the table below: Component Composition (g) Total (g) Dilution Water (kg) Water Distribution Ratio Addition Order Addition Method Result A’ Ammonium mancozeb: 90 Additive: 90 Water: 70 250 300 4 / 5 and 1 / 5 AddB’ dilution into the combined dilution of A’ and C Continuous fine stream addition Transparent suspension obtained; precipitation observed after 3.5 hours B’ Manganese sulfate: 42 Zinc sulfate: 8 50 C Pyraclostrobin (20%) Nanoemulsion: 120 Additive: 130 250 Additive Used: Alkylaryl polyoxypropylene polyoxyethylene ether / Fatty alcohol polyoxyethylene ether / Tween-80 (mass ratio 50:25:25) Operating Method: Component A' and Component B' were separately diluted using 300 kilograms of dilution water in a 4 / 5 and 1 / 5 ratio, respectively. Component C was added to the diluted solution of Component A' and evenly dispersed. Under stirring, the diluted solution of Component B' was added to the combined dilution of Component A' and Component C via continuous fine stream addition, resulting in a visually transparent mancozeb / pyraclostrobin nano-suspension. Stability lasted for 3.5 hours. Embodiment 3 The mancozeb / azoxystrobin nano-suspension is suitable for controlling late blight in potatoes. The effective ingredient dosage is 50 g / 4 g per mu, and the typical dilution water volume for spraying potatoes is approximately 30 kilograms per mu. To produce 50 grams of mancozeb, approximately 45 grams of ammonium mancozeb are required. Component Ratios: The ratios of components, dilution water volume, water distribution, addition sequence and method, and test results are presented in the table below: Component Composition (g) Total (g) Dilution Water (kg) Water Distribution Ratio Addition Order Addition Method Result A Ammonium mancozeb: 45 Azoxy strobin (4%) Nano-emulsion: 100 Additive: 50 Water: 55 250 30 2 / 3 and 1 / 3 Add B dilution into A dilution Continuous spray addition Transparent suspension obtained; precipitation observed after 3 hours B Manganese sulfate: 20.5 Zinc sulfate: 3.5 Additive: 10 Water: 216 250 Additive Used: Castor oil polyoxyethylene ether / Alkylaryl polyoxypropylene polyoxyethylene ether / Alkyl acid polyoxyethylene ether (mass ratio 40:40:20) 18 07 25 Operation Method Component A and Component B were separately diluted and dissolved using 30 kg of water, at a ratio of 2 / 3 and 1 / 3 respectively. Under stirring, the diluted solution of Component B was continuously sprayed into the diluted solution of Component A to obtain a transparent mancozeb / azoxystrobin nanosuspension. The stability time was 3 hours. Embodiment 4 The mancozeb / trifloxystrobin nano-suspension is applicable for the control of early blight in tomatoes. The effective ingredient dosage is 100 g / 4 g per mu, and the dilution water volume for spraying tomatoes is approximately 50 kg. To generate 100 grams of mancozeb, 90 grams of ammonium mancozeb are required as the precursor. Component Ratios: The ratios of components, dilution water volume, water distribution, addition sequence and method, and test results are summarized in the table below: Component Composition (g) Total (g) Dilution Water (kg) Water Distribution Ratio Addition Order Addition Method Result A Ammonium mancozeb: 90 Tnfloxy strobin (8%) Nano-emulsion: 50 Additive: 200 Water: 160 500 50 4 / 5 and 1 / 5 AddB dilution into A dilution Continuous spray addition Transparent suspension obtained; precipitation observed after 5 hours B Manganese sulfate: 42 Zinc sulfate: 8 50 Additive Used: Fatty alcohol polyoxyethylene ether / Polyoxyethylene castor oil ether / Tween-80 (mass ratio 40:40:20) Operating Method Dilute Component A and Component B separately in water at a 4 / 5 and 1 / 5 ratio based on a total of 50 kg of dilution water. Under stirring, add the diluted Component B into the diluted Component A using continuous spray addition to obtain a transparent mancozeb / trifloxystrobin nano-suspension. Tire stability time is 5 hours. Embodiment 5 The mancoze b / picoxystrobin nano-suspension can be used to control downy mildew in cucumbers. The dosage of active ingredients is 100 g / 9 g per mu, and the dilution water volume for cucumber spraying is approximately 45 kg. To generate 100 g of mancozeb, 90 g of ammonium mancozeb is required as a precursor. Component Ratios: The ratios of components, dilution water volume, water distribution, addition sequence and method, and test results are summarized in the table below: 18 07 25 Component Composition (g) Total (g) Dilution Water (kg) Water Distribution Ratio Addition Order Addition Method Result A Ammonium mancozeb: 90 Picoxystrobin (9%) Nano-emulsion: 100 Additive: 200 Water: 110 500 45 4 / 5 and 1 / 5 AddB dilution into A dilution Continuous dripping Transparent suspension obtained; precipitation observed after 4.5 hours B Manganese sulfate: 42 Zinc sulfate: 8 50 Additive OP-10 / Polyoxyethylene castor oil ether / Tween-80 (mass ratio 30:40:30) Operating Method: Component A and Component B were respectively diluted and dissolved using a total of 45 kg of water in a ratio of 4 / 5 and 1 / 5. Under stirring, the diluted solution of Component B was added into the diluted solution of Component A in a continuous thin stream. A transparent mancozeb / picoxystrobin nanosuspension was obtained, with a stability time of 4.5 hours.

Claims

18 07 251. A binary nano-suspension co-formulated with an ester-type fungicide, characterized in that the binary nano-suspension refers to a nano-suspension with particle sizes below 100 nanometers; said binary nano-suspension is formed by diluting and mixing two components with water:Component A: a water-soluble dithiocarbamate salt or an aqueous solution thereof, a water-soluble polymeric adjuvant, and water; the water-soluble dithiocarbamate salt is selected from mancozeb-ammonium, mancozeb-sodium, or mancozeb-potassium, or a mixture of at least two thereof; Meanwhile, Component A includes a nano-emulsion of a methoxyacrylate-type fungicide;Component B: a mixture of manganese salt and zinc salt in a predetermined ratio; the manganese and zinc salts are each selected from at least one type of salt.

2. Hie binary nano-suspension according to Claim 1, characterized in that the nano-suspension with particle sizes below 100 nanometers has a stability period measurable in hours.

3. The binary nano-suspension according to Claim 1, characterized in that Component B forms an aqueous solution by adding a water-soluble polymeric adjuvant and water.

4. The binary nano-suspension according to Claim 1, characterized in that the water-soluble polymeric adjuvant is a nonionic surfactant.

5. The binary nano-suspension according to Claim 1, characterized in that the ratio of the watersoluble polymeric adjuvant to the amount of diluting water is not greater than 1:1200.

6. The binary nano-suspension according to Claim 1, characterized in that when the dithiocarbamate salt, manganese salt, and zinc salt are mancozeb-ammonium, manganese sulfate, and zinc sulfate respectively, the mass ratio range is:Mancozeb-ammonium : manganese sulfate : zinc sulfate = 90 : 41-55 : 7-17;Preferably, mancozeb-ammonium : manganese sulfate : zinc sulfate = 90 : 41-43 : 7-9.

7. The binary nano-suspension according to Claim 4, characterized in that the nonionic surfactant is at least one selected from: water-soluble starch and its derivatives, water-soluble guar gum and its derivatives, polyoxypropylene-polyoxyethylene block copolymers, fatty alcohol polyoxyethylene ethers, fatty acid polyoxyethylene ethers, fatty amine polyoxyethylene ethers, alkylaryl polyoxypropylene-polyoxyethylene ethers, arylphenol polyoxyethylene ethers, castor oil polyoxyethylene ethers, alkylpolyglycosides, Tween, polyvinyl alcohol, and polyvinylpyrrolidone.

8. The binary nano-suspension according to any one of Claims 1 to 7, characterized in that the manganese salt is selected from at least one of manganese sulfate, manganese acetate, manganese chloride, and manganese nitrate; and the zinc salt is selected from at least one of zinc sulfate, zinc acetate, zinc chloride, and zinc nitrate.

9. A preparation method for the binary nano-suspension co-formulated with an ester-type fungicide according to any one of Claims 1 to 8, characterized in that under stirring conditions not less than an effective stirring speed, Component A solution is added to Component B solution, or Component B solution is added to Component A solution, to form the binary co-formulated nano-suspension.

10. The preparation method according to Claim 9, characterized in that the method of adding one component to the other is one of the following four: continuous addition, intermittent portion-wise addition, dropwise addition, or spray addition.

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