Layered seed coating method

Abstract

The invention discloses a seed layered coating method. The method sequentially comprises the following steps: coating an adhesive, coating an active chemical component and a filler, coating a compound microelement fertilizer, coating a water-retaining agent, coating a microbial agent and carbon powder, coating a warning pigment, adding a pore-foaming agent, drying, volatilizing and the like. Through layered design, comprehensive nutrition supply is provided for the seeds, and active chemical components and compound fertilizer microelement fertilizer cooperate to promote growth and development of the seeds; the water-retaining agent layer enhances the drought resistance of the seeds; the microbial agent has beneficial effects of nitrogen fixation and the like under the protection of the carbon powder isolating layer; the warning pigment layer plays a role in warning and protection, and micropores formed by the pore-foaming agent and filled water-absorbent resin further improve the gas exchange and water retention performance. Meanwhile, specific polyacrylate water-absorbent resin is filled in the micropores, so that the moisture adjusting capability of the seeds is further enhanced, and the seeds can better maintain moisture balance under different humidity conditions.

Description

Technical Field

[0001] The present invention relates to the technical field of seed coating methods, and specifically to a seed layered coating method. Background Art

[0002] Seed coating is a technology that uses film-forming agents or adhesives to evenly adhere active ingredients such as pesticides, fertilizers, and trace elements to the surface of seeds, providing guarantees for seed germination and seedling growth. It has advantages such as convenient application, low cost, promoting seedling growth, preventing pests and diseases, increasing the field survival rate of seeds, and avoiding environmental pollution. The coating agent, also known as the seed coating agent, refers to a chemical preparation processed from relevant nutrient elements, film-forming agents, medicaments, etc., with certain strength and permeability, and is directly coated on the surface of seeds for seed coating.

[0003] The seed layered coating technology is developed on the basis of the traditional homogeneous coating technology. Generally, double-layer or three-layer coating technology is adopted. The inner layer coating contains various nutrient agents, plant growth regulators, fungicides, etc.; the outer layer is generally a medicament and pesticide that are harmful to seeds. Layered coating can not only achieve the effect of the inner layer coating agent promoting seed germination and growth, but also keep the outer layer coating agent away from the seeds, avoiding phytotoxicity to the seeds, and layered coating can play a dual role at the same time. Coating each nutrient component in the seed coating agent on the surface of grass seeds in layers, adding active chemical components such as growth regulators, micronutrient fertilizers, and compound fertilizers to improve the emergence rate of grass seeds and the stress resistance during the seedling stage, adding appropriate microbial agents and water retention agents to improve the seed germination rate and emergence consistency, using warning pigments, etc. to prevent the seeds from being eaten by birds, mice, rabbits, etc. after sowing. The active strains used have multiple effects such as promoting growth and improving stress resistance, and can better adapt to the environment of the use area. However, the existing coating technologies usually aim to increase the mechanized reseeding ability of grass seeds, and there are few technical applications that assist nutrients, growth regulators, and microbial agents, etc., with the goal of restoring the entire ecosystem.

[0004] Therefore, it is necessary to provide a seed layered coating method to solve the technical problems existing in the existing seed coating methods, such as incomplete nutrient supply, poor water retention performance, lack of effective protection for microbial agents, seeds being easily damaged by animals, and unstable coating quality. Summary of the Invention

[0005] The purpose of the present invention is to provide a seed layered coating method to solve the problems raised in the above background art, as well as the problems that when seeds are in the soil, a large amount of water penetrates, which will soften and swell the film-forming agent of the warning layer coating, resulting in the failure of the warning layer and poor stability of seed germination under complex moisture conditions.

[0006] To achieve the above purpose, the present invention provides the following technical solution: A seed layered coating method, including the following steps: (1) Coating with binder Pour the naked seeds into the coating machine, and add the binder in the coating machine. After the binder is atomized by the atomizing disk of the coating machine, it wraps around the surface of the seeds to form an adhesive layer. This step can ensure that the binder is evenly atomized and tightly adheres to the surface of the seeds, providing a basis for the adhesion of subsequent multi-layer coating materials, enhancing the adhesion between each layer of coating and the seeds, ensuring the stability of the entire coating structure, enabling subsequent nutrient filling layers, composite nutrient layers, etc. to firmly wrap around the seeds, and preventing the coating from falling off during storage, transportation, and sowing.

[0007] (2) Coating with active chemical components and fillers First add the active chemical components in the coating machine, and then add the fillers. After the active chemical components and fillers are atomized by the atomizing disk, they wrap around the binder layer to form a nutrient filling layer. This step can accurately provide the key substances for promoting seed germination and early growth for the seeds. Among them, gibberellin can break seed dormancy, promote seed germination, and enable the seeds to enter the growth stage faster; micronutrient fertilizers such as zinc sulfate supplement the trace elements required for seed growth, helping to improve the stress resistance of the seeds and the robustness of the seedlings; compound fertilizers provide macronutrients such as nitrogen, phosphorus, and potassium, meeting the nutrient requirements of seed germination and early seedling growth. Subsequently, fillers such as talcum powder or kaolin are added at a speed of 0.2 - 0.5 kg / min. On the one hand, it can adjust the weight and volume of the coating to make the coating more uniform; on the other hand, the filler can also play a role in dispersing the active chemical components, preventing local high concentration from damaging the seeds, and at the same time further enhancing the mechanical strength of the coating layer to protect the seeds from external physical damage.

[0008] (3) Coating with compound fertilizer micronutrient The compound fertilizer micronutrient contains nitrogen, phosphorus, potassium, and trace elements. Add the compound fertilizer micronutrient in the coating machine. After the compound fertilizer micronutrient is atomized by the atomizing disk, it wraps around the active chemical component layer to form a composite nutrient layer. The composite nutrient layer coated in this step provides a more comprehensive and balanced nutrient supply for the continuous growth of the seeds. Different ratios of nitrogen, phosphorus, and potassium meet the requirements of the seeds for macronutrients at different growth stages, promoting the growth of plant branches and leaves, root development, and flower and fruit formation; trace elements play an important role in physiological processes such as enzyme activation and photosynthesis, helping to improve the germination rate of seeds, the survival rate of seedlings, and the overall growth performance of plants, laying a foundation for high yield and quality of crops.

[0009] (4) Coating with water-retaining agent First, the water-retaining agent is formulated into a suspension, and then added to a coating machine. After atomization by an atomizing disk, it is wrapped on the compound fertilizer and micronutrient layer to form a water-retaining layer. The water-retaining agent in this step has a strong water absorption and water retention capacity, and can absorb and store a large amount of water in the soil, just like building a small "reservoir" around the seeds. In a dry environment, the water-retaining agent slowly releases the stored water, providing continuous water guarantee for seed germination and seedling growth, significantly improving the emergence rate of seeds under water-deficient conditions and the survival rate of seedlings, enhancing the adaptability of seeds to the dry environment, and reducing the phenomenon of seed non-emergence or seedling death caused by drought.

[0010] (5)Coat with microbial inoculant and carbon powder First, add carbon powder to the coating machine. After atomization by an atomizing disk, it is wrapped on the seed surface as an isolation layer. Then, add the microbial inoculant to the coating machine. After atomization by an atomizing disk, it is wrapped on the carbon powder layer to form a microbial layer. The carbon powder isolation layer in this step can protect the microbial inoculant from the influence of external adverse environmental factors (such as ultraviolet rays, harmful substances in the soil, etc.), and extend the survival time of the microbial inoculant. Microbial inoculants such as rhizobia form a symbiotic relationship with plant roots, can fix nitrogen in the air, convert it into a nitrogen source that plants can absorb and utilize, increase the nitrogen content in the soil, and improve soil fertility. At the same time, the activities of microorganisms can also improve the soil structure, promote the release and transformation of nutrients in the soil, be beneficial to the growth and development of seeds, enhance the stress resistance of plants and the ability to absorb nutrients.

[0011] (6)Coat with warning pigment Add warning pigment to the coating machine. After atomization by an atomizing disk, it is wrapped on the microbial layer to form a warning layer. The main function of the warning pigment is to serve as a warning sign, prevent the seeds from being mistakenly eaten as ordinary food or feed, and at the same time can also reduce the pecking and gnawing of animals such as birds and insects on the seeds, reduce the risk of seed damage by animals in the field, protect the seed resources, improve the field retention rate of seeds, and ensure that a sufficient number of seeds can germinate and grow normally.

[0012] (7)Add pore-forming agent In step (6), add the pore-forming agent to the warning pigment. In this step, urea volatilizes during the subsequent drying process and forms micropores on the warning layer. These micropores increase the air permeability of the seed coating, enabling the seeds to better exchange gases with the external environment, ensuring that the seeds can breathe normally during germination, and providing necessary conditions for the physiological activities of the seeds. At the same time, the micropores are also conducive to the entry and exit of water, enabling the seeds to more quickly absorb water in the soil, promoting seed germination, and helping the slow release of nutrients in the seed coating, extending the nutrient supply time.

[0013] (8)Drying and volatilization of the pore-forming agent The coated seeds obtained in step (7) are dried at a drying temperature of 40-80 °C, and the humidity of the drying environment is between 30% and 60%. After the pore-forming agent volatilizes, micropores are formed on the warning layer. The coated seeds are dried at a drying temperature of 40-80 °C in an environment with a humidity of 30%-60% to volatilize the urea pore-forming agent to form micropores. Subsequently, a series of pretreatments are carried out on the polyacrylate superabsorbent resin and filled into the micropores. By crushing and screening, its particle size is 1 / 3 to 1 / 2 of the micropore diameter, which can ensure that the resin is smoothly filled into the micropores; plasma treatment generates hydroxyl (-OH) or carbonyl (-C=O) active groups on the resin surface, enhancing the interaction between the resin and the warning layer material, enabling the resin to firmly adhere to the inside of the micropores; it is formulated into a suspension with a mass fraction concentration of 1%-5% and the seeds are soaked in it for 10-30 min, and then taken out and dried after stirring, so that the resin is filled in the micropores. The micropores filled with the polyacrylate superabsorbent resin further enhance the water retention capacity of the seeds. In a dry environment, the resin can absorb and store more water, providing additional water reserves for the seeds, and at the same time can also regulate the humidity of the microenvironment around the seeds, which is beneficial to the germination of the seeds and the growth of the seedlings.

[0014] Preferably, in step (7), the pore-forming agent is urea, and the addition amount of urea is 10%-15% of the total mass of the warning pigment.

[0015] Preferably, in step (8), the polyacrylate superabsorbent resin is added into the micropores, and the addition steps are as follows: S1. Use a grinder to crush the polyacrylate superabsorbent resin and screen it so that its particle size is 1 / 3 to 1 / 2 of the micropore diameter; S2. Place the polyacrylate superabsorbent resin in a plasma generator for plasma treatment. Under a nitrogen gas atmosphere, hydroxyl (-OH) or carbonyl (-C=O) active groups are generated on the resin surface to enhance its interaction with the warning layer material; S3. Add the pretreated polyacrylate superabsorbent resin into deionized water to prepare a suspension with a mass fraction concentration between 1% and 5%; S4. Put the coated seeds obtained in step (8) into the superabsorbent resin suspension prepared in step S3, soak for 10-30 min, and stir; S5. After soaking, take out the seeds from the suspension, drain the excess liquid, and then dry at a temperature of 30-50 °C for 2-6 h until the surface of the seeds is completely dry and the resin is firmly filled in the micropores.

[0016] Preferably, during the coating process of steps (1) to (6), the coating machine rotates continuously at a speed of 20 to 30 r / min to evenly coat each coating agent in layers on the seed surface.

[0017] Preferably, in step (1), the binder is polyvinyl acetate, and the binder is slowly dropped onto the atomization tray of the coating machine at a speed of 0.1 to 0.2 L / min; In step (2), the active chemical components include a plant growth regulator with a concentration of 1%, a micronutrient fertilizer with a concentration of 1%, and a compound fertilizer with a concentration of 2.5%; the plant growth regulator is gibberellin, the micronutrient fertilizer is zinc sulfate, and the mass percentages of nitrogen, phosphorus, and potassium in the compound fertilizer are all 15%; the plant growth regulator solution is added at a speed of 0.05 to 0.1 L / min, the micronutrient fertilizer solution is added at a speed of 0.03 to 0.05 L / min, and the compound fertilizer solution is added at a speed of 0.1 to 0.2 L / min; the filler is talc or kaolin, and the filler is added at a speed of 0.2 to 0.5 kg / min; In step (3), the compound fertilizer micronutrient is formulated according to the ratio of nitrogen, phosphorus, potassium, and trace elements of 12:10:8:2, and the addition speed of the compound fertilizer micronutrient is 0.03 to 0.05 kg / min; In step (4), the water-retaining agent is a polyacrylamide-based water-retaining agent, and its addition speed is 0.01 to 0.03 kg / min; In step (5), the microbial inoculant is a rhizobium inoculant. First, carbon powder is evenly coated on the seed surface at a speed of 0.005 to 0.01 kg / min as an isolation layer, and then the microbial inoculant is coated on the carbon powder layer at a speed of 0.005 to 0.01 kg / min; In step (6), the addition speed of the warning layer pigment is 0.01 to 0.03 kg / min; In step (7), first dissolve the film-forming agent, then add the warning pigment for thorough mixing, and then add the pore-forming agent and stir for mixing.

[0018] Preferably, in step (8), a dehumidifier or a humidifier is used to adjust the environmental humidity.

[0019] Preferably, the addition of the binder is controlled by a flow control valve equipped on the coating machine.

[0020] Preferably, the addition of the active chemical components is controlled by a metering pump with a flow regulating device, and the addition of the filler is controlled by a vibrating feeder.

[0021] Preferably, the addition of the compound fertilizer, micronutrient fertilizer and water-retaining agent is controlled by a metering feeder; the addition of the carbon powder and microbial inoculant is controlled by a micro screw feeder.

[0022] Preferably, the addition of the warning layer pigment is carried out using a syringe with flow control and is added to the coating machine in cooperation with a syringe needle.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. In the seed germination stage, by adding a pore-forming agent to the warning pigment and the microporous structure formed by its drying and volatilization, the gas exchange and water absorption efficiency between the seeds and the external environment are greatly optimized, enabling the seeds to absorb water and oxygen from the environment more quickly, thus significantly accelerating the germination process and effectively shortening the time required for the seeds to start germinating from sowing and for the germination rate to reach a certain level. At the same time, a specific polyacrylate-based water-absorbing resin is filled in the micropores, further enhancing the water regulation ability of the seeds, enabling them to better maintain water balance under different humidity conditions, creating a more suitable microenvironment for seed germination, and improving the stability of seed germination under complex water conditions.

[0024] 2. In terms of the stability of the coating structure, the layered coating sequence and the addition method of each component ensure that the adhesive adheres to the seed surface evenly and tightly, laying a solid foundation for the adhesion of subsequent multi-layer coating materials, greatly enhancing the adhesion force between each layer of the coating and the seeds, and thus ensuring a high degree of stability of the entire coating structure during storage, transportation and sowing, effectively avoiding the occurrence of coating shedding. This enables each layer of the coating material to fully and continuously exert its functions of promoting seed germination, providing comprehensive nutrition, enhancing water retention capacity, protecting microbial inoculants, etc.

[0025] 3. In terms of the stability of the warning layer, the micropores formed by the reasonable addition of the pore-forming agent and the drying and volatilization process not only do not reduce the stability of the warning layer, but instead show excellent resistance to swelling failure in a moist soil environment. The warning layer can remain intact for a long time and continuously play its important role in preventing seeds from being accidentally eaten and reducing the pecking and gnawing of animals such as birds and insects, effectively protecting the seed resources, increasing the retention rate of seeds in the field, and providing a solid guarantee for a sufficient number of seeds to germinate and grow normally. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a line graph showing the comparison results of the starting germination time of the seeds in the examples and comparative examples of the present invention; Figure 2 It is a line graph showing the comparison results of the time required for the germination rate of the seeds in the examples and comparative examples of the present invention to reach 50%. DETAILED DESCRIPTION OF THE INVENTION

[0027] The technical solution of the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention. Embodiment

[0028] A seed layered coating method provided in this embodiment includes the following steps: (1) Coating with adhesive Pour the naked seeds into the coating machine, add the adhesive in the coating machine. After the adhesive is atomized by the atomizing disk of the coating machine, it is wrapped on the surface of the seeds to form an adhesive layer; (2) Coating with active chemical components and fillers First add the active chemical components in the coating machine, and then add the fillers. After the active chemical components and fillers are atomized by the atomizing disk, they are wrapped on the adhesive layer to form a nutrient filling layer; (3) Coating with compound fertilizer micronutrients The compound fertilizer micronutrients contain nitrogen, phosphorus, potassium and trace elements. Add the compound fertilizer micronutrients in the coating machine. After the compound fertilizer micronutrients are atomized by the atomizing disk, they are wrapped on the active chemical component layer to form a compound nutrient layer; (4) Coating with water retention agent First prepare the water retention agent into a suspension, then add it to the coating machine. After being atomized by the atomizing disk, it is wrapped on the compound fertilizer micronutrient layer to form a water retention layer; (5) Coating with microbial inoculant and carbon powder First add the carbon powder to the coating machine. After being atomized by the atomizing disk, it is wrapped on the surface of the seeds as an isolation layer; then add the microbial inoculant to the coating machine. After being atomized by the atomizing disk, it is wrapped on the carbon powder layer to form a microbial layer; (6) Coating with warning pigment Add the warning pigment to the coating machine. After being atomized by the atomizing disk, it is wrapped on the microbial layer to form a warning layer; (7) Adding pore-forming agent In step (6), add the pore-forming agent to the warning pigment; (8) Drying and volatilization of the pore-forming agent Dry the coated seeds obtained in step (7) at a drying temperature of 60°C, and the humidity of the drying environment is between 45%. After the pore-forming agent volatilizes, micropores are formed on the warning layer, and the diameter of the micropores is 10 - 1000 μm.

[0029] More specifically, in step (7), the pore-forming agent is urea, and the addition amount of urea is 12% of the total mass of the warning pigment.

[0030] More specifically, in step (8), a polyacrylate water-absorbing resin is added into the micropores, and the adding steps are as follows: S1. Use a grinder to crush the polyacrylate water-absorbing resin, and sieve it to make its particle size 1 / 3 to 1 / 2 of the micropore diameter; S2. Place the polyacrylate water-absorbing resin in a plasma generator for plasma treatment. Under a nitrogen gas atmosphere, make hydroxyl groups (~OH) or carbonyl groups (~C=O) active groups generated on the resin surface to enhance its interaction with the warning layer material; S3. Add the pretreated polyacrylate water-absorbing resin into deionized water to prepare a suspension with a mass fraction concentration of 3%; S4. Put the coated seeds obtained in step (8) into the water-absorbing resin suspension prepared in step S3, soak for 20 min, and stir; S5. After soaking, take out the seeds from the suspension, drain the excess liquid, and then dry at a temperature of 40 °C for 4 h until the seed surface is completely dry and the resin is firmly filled in the micropores.

[0031] More specifically, during the coating process of steps (1) to (6), the coating machine rotates continuously at a speed of 25 r / min to uniformly coat each coating agent on the seed surface in layers.

[0032] More specifically, in step (1), the binder is polyvinyl acetate, and the binder is slowly dropped onto the atomization disk of the coating machine at a speed of 0.15 L / min; In step (2), the active chemical components include a plant growth regulator with a concentration of 1%, a micronutrient fertilizer with a concentration of 1%, and a compound fertilizer with a concentration of 2.5%; the plant growth regulator is gibberellin, the micronutrient fertilizer is zinc sulfate, and the mass percentages of nitrogen, phosphorus, and potassium in the compound fertilizer are all 15%; the plant growth regulator solution is added at a speed of 0.075 L / min, the micronutrient fertilizer solution is added at a speed of 0.04 L / min, and the compound fertilizer solution is added at a speed of 0.15 L / min; the filler is talcum powder or kaolin, and the filler is added at a speed of 0.3 kg / min; In step (3), the compound fertilizer and micronutrient fertilizer are prepared according to the ratio of nitrogen, phosphorus, potassium, and trace elements of 12:10:8:2, and the adding speed of the compound fertilizer and micronutrient fertilizer is 0.04 kg / min; In step (4), the water-retaining agent is a polyacrylamide water-retaining agent, and its adding speed is 0.02 kg / min; In step (5), the microbial inoculant is a rhizobium inoculant. First, carbon powder is evenly wrapped on the seed surface at a speed of 0.0075 kg / min as an isolation layer, and then the microbial inoculant is wrapped on the carbon powder layer at a speed of 0.0075 kg / min; In step (6), the addition speed of the warning layer pigment is 0.02 kg / min; In step (7), first dissolve the film-forming agent, then add the warning pigment for thorough mixing, and then add the pore-forming agent and stir to mix.

[0033] More specifically, in step (8), a dehumidifier or a humidifier is used to adjust the environmental humidity.

[0034] More specifically, the addition of the binder is controlled by a flow control valve equipped on the coating machine.

[0035] More specifically, the addition of the active chemical component is controlled by a metering pump with a flow regulating device, and the addition of the filler is controlled by a vibratory feeder.

[0036] More specifically, the addition of the compound fertilizer micro-fertilizer and the water-retaining agent are both controlled by a quantitative feeder; the addition of the carbon powder and the microbial inoculant is controlled by a micro screw feeder.

[0037] More specifically, the addition of the warning layer pigment is carried out using a syringe with flow control, and a syringe needle is used in cooperation therewith and added to the coating machine. Example

[0038] A seed layered coating method provided in this example includes the same steps as in Example 1, and the only difference is that: In step (7), the pore-forming agent is urea, and the addition amount of urea is 10% of the total mass of the warning pigment.

[0039] In step (8), the coated seeds obtained in step (7) are dried at a drying temperature of 40 °C, the humidity of the drying environment is 30%%, and micropores are formed on the warning layer after the pore-forming agent volatilizes.

[0040] In step (8), the addition steps of the polyacrylate water-absorbing resin added into the micropores are as follows: S1. Use a grinder to crush the polyacrylate water-absorbing resin, and sieve it to make its particle size 1 / 3 to 1 / 2 of the micropore diameter; S2. Place the polyacrylate water-absorbing resin in a plasma generator for plasma treatment. In a nitrogen gas atmosphere, make the resin surface generate hydroxyl (-OH) or carbonyl (-C=O) active groups to enhance its interaction with the warning layer material; S3. Add the pre-treated polyacrylate superabsorbent resin into deionized water to prepare a suspension with a mass fraction concentration of 1%. S4. Put the coated seeds obtained in step (8) into the superabsorbent resin suspension prepared in step S3, soak for 10 min, and stir. S5. After soaking, take out the seeds from the suspension, drain the excess liquid, and then dry at 30 °C for 2 h until the seed surface is completely dry and the resin is firmly filled in the micropores.

[0041] During the coating process of steps (1) to (6), the coating machine rotates continuously at a speed of 20 r / min to uniformly coat each coating agent on the seed surface in layers.

[0042] In step (1), the binder is polyvinyl acetate, and the binder is slowly dropped into the atomization disk of the coating machine at a speed of 0.1 L / min. In step (2), the active chemical components include a plant growth regulator with a concentration of 1%, a micronutrient fertilizer with a concentration of 1%, and a compound fertilizer with a concentration of 2.5%; the plant growth regulator is gibberellin, the micronutrient fertilizer is zinc sulfate, and the mass percentages of nitrogen, phosphorus, and potassium in the compound fertilizer are all 15%; the plant growth regulator solution is added at a speed of 0.05 L / min, the micronutrient fertilizer solution is added at a speed of 0.03 L / min, and the compound fertilizer solution is added at a speed of 0.1 L / min; the filler is talc or kaolin, and the filler is added at a speed of 0.2 kg / min. In step (3), the compound fertilizer micronutrient is prepared according to the ratio of nitrogen, phosphorus, potassium, and trace elements of 12:10:8:2, and the addition speed of the compound fertilizer micronutrient is 0.03 kg / min. In step (4), the water-retaining agent is a polyacrylamide water-retaining agent, and its addition speed is 0.01 kg / min. In step (5), the microbial inoculant is a rhizobium inoculant. First, carbon powder is uniformly coated on the seed surface at a speed of 0.005 kg / min as an isolation layer, and then the microbial inoculant is coated on the carbon powder layer at a speed of 0.005 kg / min. In step (6), the addition speed of the warning layer pigment is 0.01 kg / min. Example

[0043] A method for layered coating of seeds provided in this example includes the same steps as in Example 1, and the only difference is that: In step (7), the pore-forming agent is urea, and the addition amount of urea is 15% of the total mass of the warning pigment.

[0044] In step (8), the coated seeds obtained in step (7) are dried at a drying temperature of 80°C, and the humidity of the drying environment is between 60%. After the porogen volatilizes, micropores are formed on the warning layer.

[0045] In step (8), the steps for adding polyacrylate superabsorbent resin into the micropores are as follows: S1. Use a grinder to crush the polyacrylate superabsorbent resin, and sieve it to make its particle size 1 / 3 - 1 / 2 of the micropore diameter; S2. Place the polyacrylate superabsorbent resin in a plasma generator for plasma treatment. Under a nitrogen gas atmosphere, make hydroxyl groups (~OH) or carbonyl groups (~C=O) active groups generated on the resin surface to enhance its interaction with the warning layer material; S3. Add the pretreated polyacrylate superabsorbent resin into deionized water to prepare a suspension with a mass fraction concentration between 5%; S4. Put the coated seeds obtained in step (8) into the superabsorbent resin suspension prepared in step S3, soak for 30 min, and stir; S5. After soaking, take out the seeds from the suspension, drain the excess liquid, and then dry at a temperature of 50°C for 6 h until the seed surface is completely dry and the resin is firmly filled in the micropores.

[0046] During the coating process of steps (1) - (6), the coating machine rotates continuously at a speed of 30 r / min to evenly coat each coating agent on the seed surface in layers.

[0047] In step (1), the binder is polyvinyl acetate, and the binder is slowly dropped into the atomization tray of the coating machine at a speed of 0.2 L / min; In step (2), the active chemical components include a plant growth regulator with a concentration of 1%, a micronutrient fertilizer with a concentration of 1%, and a compound fertilizer with a concentration of 2.5%; the plant growth regulator is gibberellin, the micronutrient fertilizer is zinc sulfate, and the mass percentages of nitrogen, phosphorus, and potassium in the compound fertilizer are all 15%; the plant growth regulator solution is added at a speed of 0.1 L / min, the micronutrient fertilizer solution is added at a speed of 0.05 L / min, and the compound fertilizer solution is added at a speed of 0.2 L / min; the filler is talcum powder or kaolin, and the filler is added at a speed of 0.5 kg / min; In step (3), the compound fertilizer micronutrient fertilizer is prepared according to the ratio of nitrogen, phosphorus, potassium, and trace elements of 12:10:8:2, and the addition speed of the compound fertilizer micronutrient fertilizer is 0.05 kg / min; In step (4), the water-retaining agent is a polyacrylamide water-retaining agent, and its addition speed is 0.03 kg / min; In step (5), the microbial inoculant is a rhizobium inoculant. First, carbon powder is evenly wrapped on the surface of the seeds at a rate of 0.01 kg / min as an isolation layer, and then the microbial inoculant is wrapped on the carbon powder layer at a rate of 0.01 kg / min; In step (6), the addition rate of the warning layer pigment is 0.03 kg / min; Comparative Example 1: The difference from the example is only that: the processes of adding and volatilizing the pore-forming agent in steps (7) and (8) are missing.

[0048] Comparative Example 2: The difference from the example is only that: in step (7), starch is used instead of urea as the pore-forming agent, and the addition amount is 12% of the total mass of the warning pigment.

[0049] Starch is difficult to volatilize to form uniform micropores under conventional drying conditions, so as to compare the effects of different pore-forming agents on micropore formation and seed performance.

[0050] Comparative Example 3: The difference from Example 1 is only that: in step (8), polyacrylate superabsorbent resin is not added into the micropores.

[0051] It is used to explore the individual effect of filling the micropores with superabsorbent resin on seed water retention and germination performance.

[0052] The experiments designed between the above comparative examples and examples and the experimental data are as follows: 1. Experiment on the change of water required for seed germination: Experimental method: Select grass seeds of the same variety and consistent plumpness, and coat them according to Example 1 and each comparative example respectively. The treated seeds are placed in petri dishes with different humidity gradients (30%, 40%, 50%, 60%, 70%), and 3 replicates are set for each humidity gradient, with 50 seeds in each replicate. Cultivate in an incubator at a temperature of 25 °C and a light of 12 h / d, record the time when the seeds start to germinate and the time required for the germination rate to reach 50%, so as to evaluate the change of water required for seed germination.

[0053] 2. Experiment on the stability of the warning layer of seeds in moist soil: Experimental method: Sow the grass seeds coated with Example 1 and each comparative example in moist (water content 60%) soil, and observe the state of the warning layer at 1 day, 3 days, 5 days, and 7 days after sowing respectively, and evaluate whether it shows the situation of swelling failure. 3 replicates are set for each treatment, and 30 seeds are sown in each replicate.

[0054] The experimental result data table is as follows:

[0055] Through setting examples and comparative examples under different conditions, this experiment explored the effects of factors such as the addition of pore-forming agents, drying conditions, filling of water-absorbing resins in micropores, and coating uniformity on seed germination and the stability of the warning layer. The following is a summary and analysis of the experimental data: 1. Effect of pore-forming agent on seed germination: By comparing Example 1 and Comparative Example 1, it can be seen that when the pore-forming agent is missing, the start time of seed germination is prolonged (48 h compared with 36 h), and the time required for the germination rate to reach 50% is also longer (60 h compared with 48 h). This shows that the micropores formed by the pore-forming agent can optimize the gas exchange and water absorption between the seeds and the outside world, and significantly accelerate the seed germination process. By comparing Example 1 and Comparative Example 2, when starch is used instead of urea as the pore-forming agent, the seed germination time is relatively long (the start germination time is 42 h, and it takes 54 h for the germination rate to reach 50%). This indicates that starch is difficult to form effective micropores, and its effect of promoting seed germination is not as good as that of urea.

[0056] 2. Effect of water-absorbing resin in micropores on seed germination: In Comparative Example 3, no polyacrylate water-absorbing resin was added in the micropores. Compared with Example 1, the start time of seed germination is slightly longer (38 h compared with 36 h), and the time required for the germination rate to reach 50% also increases (50 h compared with 48 h). This shows that filling the water-absorbing resin in the micropores can strengthen the seed's ability to regulate water, better maintain the water balance under complex water conditions, and improve the stability of seed germination.

[0057] 3. Effect of drying conditions on seed germination: After changing the drying temperature and humidity (30 °C, 80% humidity) in Comparative Example 4, both the start time of seed germination and the time required for the germination rate to reach 50% are longer than those in Example 1 (the start germination time is 40 h, and it takes 52 h for the germination rate to reach 50%). This indicates that inappropriate drying conditions will affect the quality of the micropores formed by the volatilization of the pore-forming agent, and thus have an adverse effect on seed germination.

[0058] 4. Effect of coating uniformity on seed germination: By reducing the rotation speed of the coating machine in Comparative Example 5, the coating becomes uneven, the start time of seed germination is prolonged (45 h compared with 36 h), and the time required for the germination rate to reach 50% also increases (57 h compared with 48 h). This shows that the coating uniformity will affect the contact between the seeds and water and germination. Appropriate rotation speed of the coating machine helps the coating agents to be evenly layered on the surface of the seeds, promoting seed germination.

[0059] 5. Influence of various factors on the stability of the warning layer: In the stability experiment of the warning layer, the warning layer of Example 1 remained intact for 7 days; in Comparative Examples 1-5, swelling occurred on the 3rd to 5th day, and partial or most of them failed. Comparative Example 1 lacked a pore-forming agent, resulting in an early swelling start time and fast failure of the warning layer; in Comparative Example 2, due to the poor structural stability formed by starch, the swelling and failure times of the warning layer were also earlier; in Comparative Example 3, the micropores were not filled with a water-absorbing resin, and the warning layer had slight swelling; in Comparative Example 4, the poor drying conditions affected the stability of the warning layer; in Comparative Example 5, the coating was uneven, causing the warning layer of some seeds to swell first at the weak points, and then the warning layers of more seeds failed.

[0060] Experiments show that the pore-forming agent, the water-absorbing resin in the micropores, suitable drying conditions, and the appropriate rotation speed of the coating machine have a positive effect on promoting seed germination and enhancing the stability of the warning layer. The layered coating method of the present invention effectively solves the problems existing in the existing seed coating technology and improves the seed performance by optimizing these factors.

[0061] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention.

Claims

1. A seed layer coating method, characterized in that: The following steps are involved: The naked seeds are coated with adhesive, active chemical ingredients, compound fertilizer, micro-fertilizer, water-retaining agent, microbial agent, carbon powder and warning pigment in sequence by using a coating machine; during the coating process, the coating machine rotates continuously at a speed of 20 to 30 r / min; In the preparation process of the warning pigment, urea is added as a pore-forming agent, and the amount of urea added is 10% to 15% of the total mass of the warning pigment; The coated seeds are dried at a drying temperature of 40 to 80° C., the humidity of the drying environment is between 30% and 60%, micropores are formed on the warning pigment coating layer after the porogen is volatilized, and polyacrylate water-absorbing resin is added into the micropores.

2. A seed layer coating method according to claim 1, characterized in that: The adhesive is polyvinyl acetate, and its adding process is controlled by a flow control valve equipped on the coating machine. The adhesive slowly drips into the atomizing disk of the coating machine at a speed of 0.1 to 0.2 L / min.

3. A seed layer coating method according to claim 1, characterized in that: The active chemical components include a plant growth regulator with a concentration of 1%, a micro-fertilizer with a concentration of 1%, and a compound fertilizer with a concentration of 2.5%; The plant growth regulator is gibberellin, the micro-fertilizer is zinc sulfate, and the mass percentages of nitrogen, phosphorus, and potassium in the compound fertilizer are all 15%; The addition of the active chemical components is controlled by a metering pump with a flow regulating device, the plant growth regulator solution is added at a rate of 0.05-0.1 L / min, the micro-fertilizer solution is added at a rate of 0.03-0.05 L / min, and the compound fertilizer solution is added at a rate of 0.1-0.2 L / min; After the above active chemical components are added, a filler is added. The addition of the filler is controlled by a vibrating feeder. The filler is talcum powder or kaolin. The filler is added at a speed of 0.2-0.5 kg / min.

4. A seed layer coating method according to claim 1, characterized in that: The compound fertilizer and micro-fertilizer are prepared according to the ratio of nitrogen, phosphorus, potassium and trace elements of 12:10:8:

2. The addition of the compound fertilizer and micro-fertilizer is controlled by a quantitative feeder, and the addition speed of the compound fertilizer and micro-fertilizer is 0.03-0.05 kg / min.

5. A seed layer coating method according to claim 1, characterized in that: The water retaining agent is a polyacrylamide water retaining agent, and the addition of the water retaining agent is controlled by a quantitative feeder, and the adding speed thereof is 0.01 to 0.03 kg / min.

6. A seed layer coating method according to claim 1, characterized in that: The microbial agent is a rhizobium agent, and the addition of the carbon powder and the microbial agent is controlled by a micro-screw feeder. The carbon powder is first evenly wrapped on the seed surface at a speed of 0.005-0.01kg / min as an isolation layer, and then the microbial agent is wrapped on the carbon powder layer at a speed of 0.005-0.01kg / min.

7. A seed layer coating method according to claim 1, characterized in that: The warning layer pigment is added using a syringe with flow control, and a needle tube is used to match it and added to the coating machine. The adding speed of the warning layer pigment is 0.01-0.03 kg / min.

8. A seed layer coating method according to claim 7, characterized in that: In the preparation process of the warning layer pigment, the film former is first dissolved, and then the warning pigment is added and mixed thoroughly, and then the pore former is added and stirred and mixed.

9. A seed layer coating method according to any one of claims 1 to 8, characterized in that: The steps of adding the polyacrylic acid salt water-absorbing resin into the micropores are as follows: S1, using a grinder to grind the polyacrylic acid salt water-absorbing resin, and sieving it to make its particle size 1 / 3 to 1 / 2 of the micropore diameter; S2. Placing the polyacrylate water-absorbing resin in a plasma generator for plasma treatment, and generating hydroxyl (-OH) or carbonyl (-C=O) active groups on the resin surface in a nitrogen atmosphere to enhance its interaction with the warning layer material; S3, adding the pretreated polyacrylate water-absorbing resin into deionized water to prepare a suspension having a mass fraction concentration between 1% and 5%; S4, placing the coated seeds into the water-absorbing resin suspension prepared in step S3, soaking for 10 to 30 minutes, and stirring; S5. After the soaking is completed, the seeds are taken out from the suspension, the excess liquid is drained, and then dried at a temperature of 30 to 50°C for 2 to 6 hours until the surface of the seeds is completely dry and the resin is firmly filled in the micropores.

10. A seed layer coating method according to claim 9, characterized in that: The micropores have a diameter of 10-1000 μm.

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