Seedling raising nutrient solution for improving root tillering capacity of sugarcane and preparation method thereof

Abstract

The application discloses a seedling raising nutrient solution for improving the tillering capacity of sugarcane roots and a preparation method thereof, and comprises the following steps: S1, preparation of pretreated attapulgite; S2, preparation of modified attapulgite; S3, preparation of a nano nutrient element solution; S4, preparation of a biosynthetic organic matter slurry; and S5, preparation of the seedling raising nutrient solution. The seedling raising nutrient solution is prepared by scientifically compounding the modified attapulgite, the composite nutrient element, the organic matter produced by biological fermentation and chitosan, and forms a high-efficiency synergistic nutrient supply and plant growth regulation system. The nutrient solution can not only improve the absorption and utilization efficiency of essential nutrient elements by the sugarcane, but also effectively stimulates the root growth and tillering point formation, thereby increasing the effective stem number per unit area, and further improving the yield of the sugarcane and the ratooning property, and the nutrient solution makes up for the deficiency of the prior art that the nutrient solution cannot effectively improve the tillering capacity of the sugarcane roots.

Description

Technical Field

[0001] This invention belongs to the technical field, specifically relating to a seedling nutrient solution for improving the tillering ability of sugarcane roots and its preparation method. Background Technology

[0002] Sugarcane is an important sugar crop widely cultivated in tropical and subtropical regions. In recent years, the majority of the world's sugar supply has come from sugarcane sugar. Sugarcane stalks are crucial for sugar storage and harvesting; therefore, increasing sugarcane yield essentially means increasing the yield per unit area of ​​sugarcane stalks (i.e., yield per unit area). Effective stalks are a component of sugarcane yield, and promoting tillering is key to increasing the number of effective stalks per unit area. Tillering is a special developmental biological phenomenon that occurs during the growth and development of gramineous plants such as rice, wheat, barley, sorghum, and sugarcane. Tillering affects the number of spikelets and thus the crop yield per unit area. Promoting tillering and stalk formation is the most effective way to increase the number of effective stalks per unit area of ​​sugarcane. Ratoon sugarcane is an important component of sugarcane production, accounting for a considerable proportion of the planted area, generally 70%–80% of the total planted area. Furthermore, the tillering rate of sugarcane is significantly positively correlated with its ratooning ability; sugarcane varieties with a higher tillering rate have better ratooning ability. Therefore, regulating tillering and stem formation has important guiding significance for the high-efficiency and high-yield cultivation of sugarcane.

[0003] In traditional sugarcane cultivation, the tillering ability of the root system is constrained by various factors such as soil fertility, water, and climate. Conventional fertilizers are difficult to precisely meet the root system's demand for efficient absorption of nutrients during the critical tillering period. While some existing fertilizers can provide nutrients, they suffer from problems such as limited nutrient composition, element forms that are not conducive to root absorption, and the potential to cause soil compaction and environmental pollution.

[0004] Chinese patent application CN107337535A discloses a nutrient solution containing pesticides and fertilizers for controlling pests and diseases in ratoon sugarcane stubble and a method thereof. The method includes steps such as preparing the nutrient solution, treating the sugarcane stubble, cleaning the sugarcane field, applying the nutrient solution, and mulching. This invention involves applying the nutrient solution at a rate of 450 kg / hm² after treating the sugarcane stubble and cleaning the sugarcane field. 2This invention can effectively prevent and control diseases and pests in sugarcane stubble, increase the number of seedlings emerging from ratoon sugarcane, and also replenish the nutrients needed by sugarcane in a timely manner to promote the healthy growth of sugarcane seedlings. The nutrient solution containing the pesticide and fertilizer in this invention is scientifically formulated to meet the characteristics of diseases and pests in ratoon sugarcane stubble and fertilizer requirements. It is effective against sugarcane pineapple disease, red rot, stem borers, termites, and beetles, while also taking into account the fertilizer requirements of sugarcane, and adding nutrients such as nitrogen, phosphorus, potassium, magnesium, zinc, and boron required by sugarcane. Chinese patent application CN105272648A discloses a nutrient solution for promoting sugarcane growth and its preparation method, belonging to the field of agricultural planting technology. The nutrient solution comprises the following components by weight: 10-20 parts indoleacetic acid, 15-25 parts chlorophyll, 10-20 parts ethylene, 10-20 parts abscisic acid, 10-20 parts gibberellin, 2-5 parts vitamin C, 5-10 parts lime, and 60-70 parts water. The preparation method involves mixing the components evenly according to their weight proportions, homogenizing at 25-30℃, 2000-4000 RPM, and 1-3 atmospheres for 10-30 minutes, maintaining the temperature at 30-35℃ for 30-40 minutes, and adjusting the pH to 6.0-7.0. The nutrient solution contains lime to prevent bacterial infection during sugarcane growth, ensuring its healthy development. It is simple to store, convenient to transport, and easy to use. However, the nutrient solution in the above invention is only effective against pests and diseases of sugarcane rootstock or only promotes the growth of sugarcane, and cannot improve the tillering ability of sugarcane roots.

[0005] Therefore, developing a seedling nutrient solution that enhances sugarcane's nutrient absorption efficiency, promotes root growth and tillering, and improves sugarcane yield and quality has become a key direction for improving the benefits of sugarcane cultivation. Summary of the Invention

[0006] In view of the shortcomings of the prior art, the purpose of this invention is to provide a seedling nutrient solution and its preparation method for improving the tillering ability of sugarcane roots.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A method for preparing a seedling nutrient solution to improve the tillering ability of sugarcane roots includes the following steps:

[0009] S1. Preparation of pretreated attapulgite: Add attapulgite to nitric acid solution for impregnation treatment. After treatment, filter and add the solid product to an ethanol aqueous solution. Then add γ-glycidoxypropyltrimethoxysilane and stir to react. After the reaction is completed, filter, wash and dry to obtain pretreated attapulgite.

[0010] S2. Preparation of modified attapulgite: The pretreated attapulgite from step S1 is added to N,N-dimethylformamide, followed by the addition of 4-imidazolium acrylic acid and N,N-dimethylcyclohexylamine. The mixture is heated and reacted. After the reaction is complete, the mixture is filtered, washed, and dried to obtain organic attapulgite. The organic attapulgite is then added to deionized water, followed by the addition of oleyl alcohol polyoxyethylene ether and potassium persulfate. The mixture is reacted at a constant temperature. After the reaction is complete, the mixture is filtered, washed, and dried to obtain modified attapulgite.

[0011] S3. Preparation of nano-nutrient element solution: Zinc sulfate, copper nitrate, and potassium dihydrogen phosphate were added to deionized water and stirred evenly to obtain a composite element solution; then modified attapulgite was added to the nutrient element solution and subjected to ultrasonic treatment to obtain nano-nutrient element solution.

[0012] S4. Preparation of biosynthetic organic matter slurry: Sugarcane bagasse and soybean cake are mixed evenly to obtain a mixture. Then Bacillus subtilis and cellulase are added, and the water content is adjusted. Fermentation is carried out, and biosynthetic organic matter slurry is obtained after fermentation.

[0013] S5. Preparation of seedling nutrient solution: Mix the nano-nutrient element solution in step S3 with the biosynthetic organic slurry in step S4 to obtain a mixture. Then add chitosan and stir. After stirring evenly, the seedling nutrient solution is obtained.

[0014] Preferably, the mass concentration of the nitric acid solution in step S1 is 15-20%, the temperature of the impregnation treatment is 30-40°C, and the time is 1-2 hours.

[0015] Preferably, in step S1, the mass ratio of the solid product to γ-glycidyl etheroxypropyltrimethoxysilane is 90-100:8-11, and the stirring reaction is carried out at a temperature of 50-60°C for 2-3 hours.

[0016] In this invention, attapulgite is used as a carrier material. Its natural nanoscale rod-like structure and large specific surface area provide a basis for subsequent chemical modification and nutrient loading. Through acid activation treatment, impurities in its surface and pores are removed, the pores are cleared, and the number of surface silanol active sites is increased. Subsequently, it is reacted with γ-glycidoxypropyltrimethoxysilane to introduce highly active epoxy groups, providing a basis for subsequent modification.

[0017] Preferably, in step S2, the mass ratio of the pretreated attapulgite, 4-imidazolium acrylic acid, and N,N-dimethylcyclohexylamine is 90-100:12-16:2-3, and the heating reaction temperature is 80-90℃ for 3-4 hours.

[0018] In this invention, the epoxy groups in attapulgite soil are reacted with the carboxyl groups of 4-imidazolium acrylic acid during pretreatment, and groups containing imidazolium rings and acrylic acid double bonds are covalently grafted onto the attapulgite soil. On the one hand, the introduced imidazolium ring has excellent metal ion chelating ability, which can effectively adsorb and stabilize trace elements (zinc ions and copper ions) that are crucial for sugarcane tillering. It can also interact with phosphates to a certain extent, thereby helping to concentrate various nutrients (metal trace elements and phosphorus) more closely near the modified attapulgite soil carrier, forming a nutrient-rich micro-region, which is conducive to its subsequent slow release and synchronous absorption by the roots. On the other hand, the acrylic acid double bonds provide reaction sites for the subsequent grafting of oleyl alcohol polyoxyethylene ether.

[0019] Preferably, in step S2, the mass ratio of the organic attapulgite, oleyl alcohol polyoxyethylene ether, and potassium persulfate is 90-100:4-5:0.3-0.5, the isothermal reaction temperature is 65-75℃, and the time is 1-2 hours.

[0020] In this invention, nonionic surfactant oleyl alcohol polyoxyethylene ether is grafted onto the surface of attapulgite soil via free radical reaction, significantly improving the dispersibility and suspension stability of the modified attapulgite soil in the aqueous phase, preventing nanoparticle aggregation, and facilitating the uniform application of nutrient solution and its contact and absorption by plant roots. More importantly, this improves the spreading and wetting properties of the nutrient solution on the sugarcane root surface, enhancing the affinity and absorption efficiency of the roots for the various effective components in the nutrient solution. At the same time, because the surfactant is chemically bonded to the carrier, its degree of freeness is greatly reduced, effectively avoiding the potential physiological stress or negative impacts caused by excessive absorption and accumulation of free surfactant on the sugarcane roots, thereby ensuring the safety of sugarcane growth while improving nutrient absorption efficiency.

[0021] Preferably, in step S3, the mass ratio of zinc sulfate, copper nitrate, potassium dihydrogen phosphate, and deionized water is 7-10:4-6:19-24:1000, the amount of modified attapulgite added is 6-8% of the mass of the composite element solution, the frequency of the ultrasonic treatment is 30-40kHz, the power is 200-250W, and the time is 30-40min.

[0022] In this invention, modified attapulgite serves as a nanocarrier. Its surface imidazole groups chelate zinc and copper ions, while its porous structure and large specific surface area also adsorb phosphate and potassium ions. These nutrients are loaded onto the nanocarrier to form nanoscale nutrient particles. This helps to improve the stability of nutrients in solution, prevents them from precipitating or being fixed by the soil, achieves slow release of nutrients, improves their bioavailability and duration of effectiveness, and reduces loss.

[0023] Preferably, in step S4, the mass ratio of sugarcane bagasse to soybean cake is 7-8:2-3, the amount of Bacillus subtilis added is 1-2% of the mass of the mixture, the amount of cellulase added is 2-3% of the mass of the mixture, and the moisture content is 60-70%.

[0024] Preferably, the fermentation temperature in step S4 is 30-35℃ and the time is 72-96h.

[0025] In this invention, sugarcane bagasse and soybean cake are used as organic substrates for microbial fermentation. Sugarcane bagasse is rich in carbohydrates such as cellulose and hemicellulose, while soybean cake is rich in protein (nitrogen source) and various amino acids. Through fermentation, they are transformed into an organic slurry rich in humus, organic acids, amino acids, vitamins, and various bioactive substances. This slurry can improve the physical and chemical properties of the soil, activate nutrients, promote root development, and provide sugarcane with comprehensive organic nutrition and growth stimulants.

[0026] Preferably, in step S5, the mass ratio of the nanonutrient element solution to the biosynthetic organic slurry is 1:2-3, the amount of chitosan added is 0.4-0.7% of the mass of the mixture, the stirring rate is 700-900 r / min, and the stirring time is 2-3 h.

[0027] In this invention, the nano-nutrient element solution, biosynthetic organic slurry, and chitosan are thoroughly mixed evenly. Chitosan, as a natural biopolysaccharide and plant growth regulator, has the ability to stimulate plant growth and induce disease resistance. At the same time, the amino and hydroxyl groups on its molecular chain have a certain chelating ability, which can further stabilize the nano-nutrient elements and act as a thickener to improve the physical properties of the nutrient solution. This ensures that the components of the final seedling nutrient solution are evenly distributed and stable, thereby guaranteeing the consistency and effectiveness of the application.

[0028] The present invention also protects a seedling nutrient solution for improving the tillering ability of sugarcane roots, prepared by the method described above.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] (1) The seedling nutrient solution provided by the present invention for improving the tillering ability of sugarcane roots is formed by scientifically compounding modified attapulgite soil, compound nutrients, organic matter produced by bio-fermentation and chitosan, forming an efficient and synergistic nutrient supply and plant growth regulation system. This nutrient solution can not only improve the absorption and utilization efficiency of sugarcane for essential nutrients, but also effectively stimulate root growth and tillering point formation, thereby increasing the number of effective stems per unit area, thereby increasing sugarcane yield and improving ratooning ability, making up for the shortcomings of the existing nutrient solution in effectively improving the tillering ability of sugarcane roots.

[0031] (2) The seedling nutrient solution for improving the tillering ability of sugarcane provided by this invention incorporates modified attapulgite soil. This modified attapulgite soil undergoes nitric acid activation, pre-grafting of epoxy groups with γ-glycidyl etheroxypropyltrimethoxysilane, followed by covalent bonding of 4-imidazolium acrylic acid to introduce an imidazolium ring with metal ion chelating ability and acrylic acid double bonds for further reaction. Finally, it is grafted with oleyl alcohol polyoxyethylene ether. This modified attapulgite soil not only effectively loads and nano-sized nutrients, achieving slow-release delivery in the soil, but also enhances the affinity and stability for trace elements such as zinc and copper through specific functional groups (such as imidazolium rings) introduced on its surface. This significantly improves the bioavailability of these key tillering-promoting elements in the rhizosphere, thereby further enhancing the tillering ability of sugarcane. It precisely meets the specific nutritional needs of sugarcane during the tillering stage; furthermore, oleyl alcohol polyoxyethylene ether is covalently grafted onto the surface of organic attapulgite soil, endowing the modified attapulgite soil with excellent surface activity and significantly reducing the degree of surfactant freeness. The presence of this grafted surfactant can, on the one hand, improve the spreading and wetting performance of nutrient solution on the sugarcane root surface, and enhance the affinity and absorption efficiency of the roots for the various effective components in the nutrient solution; on the other hand, since the surfactant is bound to the carrier, it effectively avoids the potential physiological stress or negative impact of excessive absorption and accumulation of free surfactant on the sugarcane roots, thereby improving nutrient absorption efficiency while ensuring the safety of sugarcane growth.

[0032] (3) The seedling nutrient solution for improving the tillering ability of sugarcane roots provided by the present invention combines a biosynthetic organic slurry derived from agricultural waste such as sugarcane bagasse and soybean cake, which is obtained by co-fermentation of Bacillus subtilis and cellulase, with nano-nutrient elements and chitosan. This organic slurry is rich in organic acids, amino acids, humus, plant growth stimulants and beneficial microorganisms, which can effectively improve the rhizosphere microenvironment, enhance root vitality and promote nutrient absorption. By combining organic-inorganic-biological phases, the seedling nutrient solution can provide balanced mineral nutrition while regulating the physiological and biochemical processes of sugarcane, and synergistically amplify the promoting effect on root development and tillering, thus achieving the dual goals of resource utilization of agricultural waste and increased sugarcane yield and quality. Detailed Implementation

[0033] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0034] Unless otherwise specified, all chemical reagents and materials in this invention are purchased from the market or synthesized from raw materials purchased from the market.

[0035] The attapulgite clay has a particle size of 100-150 nm; the oleyl alcohol polyoxyethylene ether was purchased from Haian Petrochemical Plant in Jiangsu Province, and its brand name is oleyl alcohol polyoxyethylene ether OV-5; the Bacillus subtilis was purchased from Bacillus subtilis, and its viable count is ≥1×10⁻⁶. 11 cfu / g; the enzyme activity of the cellulase is 20,000 U / g.

[0036] Example 1

[0037] A method for preparing a seedling nutrient solution to improve the tillering ability of sugarcane roots includes the following steps:

[0038] S1. Preparation of pretreated attapulgite: 1 kg of attapulgite was added to 10 kg of 20% nitric acid solution and impregnated at 35°C for 1.5 h. After treatment, the mixture was filtered. 0.95 kg of the solid product was added to 12 kg of ethanol aqueous solution (ethanol to water mass ratio of 3:1). Then 100 g of γ-glycidoxypropyltrimethoxysilane was added and stirred at 55°C for 2.5 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain pretreated attapulgite.

[0039] S2. Preparation of modified attapulgite: 0.95 kg of pretreated attapulgite from step S1 was added to 12 kg of N,N-dimethylformamide, followed by 140 g of 4-imidazolium acrylic acid and 25 g of N,N-dimethylcyclohexylamine. The mixture was reacted at 80-90 °C for 3.5 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain organic attapulgite. 0.95 kg of organic attapulgite was added to 15 kg of deionized water, followed by 45 g of oleyl alcohol polyoxyethylene ether and 4 g of potassium persulfate. The mixture was reacted at a constant temperature of 70 °C for 1.5 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain modified attapulgite.

[0040] S3. Preparation of nano-nutrient element solution: Add 90g zinc sulfate, 50g copper nitrate, and 220g potassium dihydrogen phosphate to 10kg deionized water and stir evenly to obtain a composite element solution; then add 70g modified attapulgite clay to 10kg nutrient element solution and perform ultrasonic treatment at a frequency of 35kHz, a power of 230W, and a time of 35min to obtain nano-nutrient element solution.

[0041] S4. Preparation of biosynthetic organic matter slurry: Sugarcane bagasse and soybean cake with a mass ratio of 7.5:2.5 are mixed evenly to obtain a mixture. Then, 1.5% of Bacillus subtilis and 2.5% of cellulase by mass of the mixture are added, and the moisture content is adjusted to 65%. Fermentation is carried out at 33℃ for 84 hours. After fermentation, biosynthetic organic matter slurry is obtained.

[0042] S5. Preparation of seedling nutrient solution: The nano-nutrient element solution in step S3 and the biosynthetic organic slurry in step S4 are mixed evenly at a mass ratio of 1:2.5 to obtain a mixed solution. Then, 0.6% of chitosan by mass of the mixed solution is added and stirred at 800 r / min for 2.5 h. After stirring evenly, the seedling nutrient solution is obtained.

[0043] Example 2

[0044] A method for preparing a seedling nutrient solution to improve the tillering ability of sugarcane roots includes the following steps:

[0045] S1. Preparation of pretreated attapulgite: 1 kg of attapulgite was added to 10 kg of 15% nitric acid solution and impregnated at 30°C for 2 h. After treatment, the mixture was filtered. 0.9 kg of the solid product was added to 12 kg of ethanol aqueous solution (ethanol to water mass ratio of 3:1). Then 80 g of γ-glycidoxypropyltrimethoxysilane was added and stirred at 50°C for 3 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain pretreated attapulgite.

[0046] S2. Preparation of modified attapulgite: 0.9 kg of pretreated attapulgite from step S1 was added to 12 kg of N,N-dimethylformamide, followed by 120 g of 4-imidazolium acrylic acid and 20 g of N,N-dimethylcyclohexylamine. The mixture was reacted at 80 °C for 4 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain organic attapulgite. 0.9 kg of organic attapulgite was added to 15 kg of deionized water, followed by 40 g of oleyl alcohol polyoxyethylene ether and 3 g of potassium persulfate. The mixture was reacted at 65 °C for 2 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain modified attapulgite.

[0047] S3. Preparation of nano-nutrient element solution: Add 70g zinc sulfate, 40g copper nitrate and 190g potassium dihydrogen phosphate to 10kg deionized water and stir evenly to obtain a composite element solution; then add 60g modified attapulgite clay to 10kg nutrient element solution and perform ultrasonic treatment at a frequency of 40kHz, a power of 200W and a time of 40min to obtain nano-nutrient element solution.

[0048] S4. Preparation of biosynthetic organic matter slurry: Sugarcane bagasse and soybean cake in a mass ratio of 8:2 are mixed evenly to obtain a mixture. Then, 1% of Bacillus subtilis and 2% of cellulase by mass of the mixture are added, and the moisture content is adjusted to 60%. Fermentation is carried out at 30℃ for 96 hours. After fermentation, biosynthetic organic matter slurry is obtained.

[0049] S5. Preparation of seedling nutrient solution: The nano-nutrient element solution in step S3 and the biosynthetic organic slurry in step S4 are mixed evenly at a mass ratio of 1:2 to obtain a mixture. Then, 0.4% of chitosan by mass of the mixture is added and stirred at 700 r / min for 3 h. After stirring evenly, the seedling nutrient solution is obtained.

[0050] Example 3

[0051] A method for preparing a seedling nutrient solution to improve the tillering ability of sugarcane roots includes the following steps:

[0052] S1. Preparation of pretreated attapulgite: 1 kg of attapulgite was added to 10 kg of 20% nitric acid solution and impregnated at 40°C for 1 h. After treatment, the mixture was filtered. 1 kg of the solid product was added to 12 kg of ethanol aqueous solution (ethanol to water mass ratio of 3:1). Then 110 g of γ-glycidoxypropyltrimethoxysilane was added and stirred at 60°C for 2 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain pretreated attapulgite.

[0053] S2. Preparation of modified attapulgite: 1 kg of pretreated attapulgite from step S1 was added to 12 kg of N,N-dimethylformamide, followed by 160 g of 4-imidazolium acrylic acid and 30 g of N,N-dimethylcyclohexylamine. The mixture was reacted at 90 °C for 3 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain organic attapulgite. 1 kg of organic attapulgite was added to 15 kg of deionized water, followed by 50 g of oleyl alcohol polyoxyethylene ether and 5 g of potassium persulfate. The mixture was reacted at 75 °C for 1 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain modified attapulgite.

[0054] S3. Preparation of nano-nutrient element solution: Add 100g zinc sulfate, 60g copper nitrate, and 240g potassium dihydrogen phosphate to 10kg deionized water and stir evenly to obtain a composite element solution; then add 80g modified attapulgite clay to 10kg nutrient element solution and perform ultrasonic treatment at a frequency of 30kHz, a power of 250W, and a time of 30min to obtain nano-nutrient element solution.

[0055] S4. Preparation of biosynthetic organic matter slurry: Sugarcane bagasse and soybean cake in a mass ratio of 7:3 are mixed evenly to obtain a mixture. Then, 2% of Bacillus subtilis and 3% of cellulase by mass of the mixture are added, and the moisture content is adjusted to 70%. Fermentation is carried out at 35℃ for 72 hours. After fermentation, biosynthetic organic matter slurry is obtained.

[0056] S5. Preparation of seedling nutrient solution: The nano-nutrient element solution in step S3 and the biosynthetic organic slurry in step S4 are mixed evenly at a mass ratio of 1:3 to obtain a mixture. Then, 0.7% of chitosan by mass of the mixture is added and stirred at 900 r / min for 2 hours. After stirring evenly, the seedling nutrient solution is obtained.

[0057] Comparative Example 1

[0058] A method for preparing a seedling nutrient solution to improve the tillering ability of sugarcane roots includes the following steps:

[0059] S1. Preparation of pretreated attapulgite: 1 kg of attapulgite was added to 10 kg of 20% nitric acid solution and impregnated at 35°C for 1.5 h. After treatment, the mixture was filtered. 0.95 kg of the solid product was added to 12 kg of ethanol aqueous solution (ethanol to water mass ratio of 3:1). Then 100 g of γ-glycidoxypropyltrimethoxysilane was added and stirred at 55°C for 2.5 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain pretreated attapulgite.

[0060] S2. Preparation of modified attapulgite: 0.95 kg of pretreated attapulgite from step S1 was added to 12 kg of N,N-dimethylformamide, followed by 140 g of 4-imidazolium acrylic acid and 25 g of N,N-dimethylcyclohexylamine. The mixture was reacted at 80-90 °C for 3.5 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain modified attapulgite.

[0061] S3. Preparation of nano-nutrient element solution: Add 90g zinc sulfate, 50g copper nitrate, and 220g potassium dihydrogen phosphate to 10kg deionized water and stir evenly to obtain a composite element solution; then add 70g modified attapulgite clay to 10kg nutrient element solution and perform ultrasonic treatment at a frequency of 35kHz, a power of 230W, and a time of 35min to obtain nano-nutrient element solution.

[0062] S4. Preparation of biosynthetic organic matter slurry: Sugarcane bagasse and soybean cake with a mass ratio of 7.5:2.5 are mixed evenly to obtain a mixture. Then, 1.5% of Bacillus subtilis and 2.5% of cellulase by mass of the mixture are added, and the moisture content is adjusted to 65%. Fermentation is carried out at 33℃ for 84 hours. After fermentation, biosynthetic organic matter slurry is obtained.

[0063] S5. Preparation of seedling nutrient solution: The nano-nutrient element solution in step S3 and the biosynthetic organic slurry in step S4 are mixed evenly at a mass ratio of 1:2.5 to obtain a mixed solution. Then, 0.6% of chitosan by mass of the mixed solution is added and stirred at 800 r / min for 2.5 h. After stirring evenly, the seedling nutrient solution is obtained.

[0064] Compared to Example 1, this comparative example did not introduce oleyl alcohol polyoxyethylene ether onto the attapulgite.

[0065] Comparative Example 2

[0066] A method for preparing a seedling nutrient solution to improve the tillering ability of sugarcane roots includes the following steps:

[0067] S1. Preparation of pretreated attapulgite: 1 kg of attapulgite was added to 10 kg of 20% nitric acid solution and impregnated at 35°C for 1.5 h. After treatment, the mixture was filtered. 0.95 kg of the solid product was added to 12 kg of ethanol aqueous solution (ethanol to water mass ratio of 3:1). Then 100 g of γ-glycidoxypropyltrimethoxysilane was added and stirred at 55°C for 2.5 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain pretreated attapulgite.

[0068] S2. Preparation of modified attapulgite: 0.95 kg of pretreated attapulgite from step S1 was placed in 15 kg of deionized water, followed by the addition of 45 g of oleyl alcohol polyoxyethylene ether and 4 g of potassium persulfate. The mixture was reacted at a constant temperature of 70 °C for 1.5 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain modified attapulgite.

[0069] S3. Preparation of nano-nutrient element solution: Add 90g zinc sulfate, 50g copper nitrate, and 220g potassium dihydrogen phosphate to 10kg deionized water and stir evenly to obtain a composite element solution; then add 70g modified attapulgite clay to 10kg nutrient element solution and perform ultrasonic treatment at a frequency of 35kHz, a power of 230W, and a time of 35min to obtain nano-nutrient element solution.

[0070] S4. Preparation of biosynthetic organic matter slurry: Sugarcane bagasse and soybean cake with a mass ratio of 7.5:2.5 are mixed evenly to obtain a mixture. Then, 1.5% of Bacillus subtilis and 2.5% of cellulase by mass of the mixture are added, and the moisture content is adjusted to 65%. Fermentation is carried out at 33℃ for 84 hours. After fermentation, biosynthetic organic matter slurry is obtained.

[0071] S5. Preparation of seedling nutrient solution: The nano-nutrient element solution in step S3 and the biosynthetic organic slurry in step S4 are mixed evenly at a mass ratio of 1:2.5 to obtain a mixed solution. Then, 0.6% of chitosan by mass of the mixed solution is added and stirred at 800 r / min for 2.5 h. After stirring evenly, the seedling nutrient solution is obtained.

[0072] Compared to Example 1, this comparative example did not introduce 4-imidazolium acrylic acid into attapulgite.

[0073] Comparative Example 3

[0074] A method for preparing a seedling nutrient solution to improve the tillering ability of sugarcane roots includes the following steps:

[0075] S1. Preparation of pretreated attapulgite: 1 kg of attapulgite was added to 10 kg of 20% nitric acid solution and impregnated at 35°C for 1.5 h. After treatment, the mixture was filtered. 0.95 kg of the solid product was added to 12 kg of ethanol aqueous solution (ethanol to water mass ratio of 3:1). Then 100 g of γ-glycidoxypropyltrimethoxysilane was added and stirred at 55°C for 2.5 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain pretreated attapulgite.

[0076] S2. Preparation of nano-nutrient element solution: Add 90g zinc sulfate, 50g copper nitrate, and 220g potassium dihydrogen phosphate to 10kg deionized water and stir evenly to obtain a composite element solution; then add 70g pretreated attapulgite clay to 10kg nutrient element solution and perform ultrasonic treatment at a frequency of 35kHz, a power of 230W, and a time of 35min to obtain nano-nutrient element solution.

[0077] S3. Preparation of biosynthetic organic matter slurry: Sugarcane bagasse and soybean cake in a mass ratio of 7.5:2.5 are mixed evenly to obtain a mixture. Then, 1.5% of Bacillus subtilis and 2.5% of cellulase by mass of the mixture are added, and the moisture content is adjusted to 65%. Fermentation is carried out at 33℃ for 84 hours. After fermentation, biosynthetic organic matter slurry is obtained.

[0078] S4. Preparation of seedling nutrient solution: The nano-nutrient element solution in step S2 and the biosynthetic organic slurry in step S3 are mixed evenly at a mass ratio of 1:2.5 to obtain a mixture. Then, 0.6% of chitosan by mass of the mixture is added and stirred at 800 r / min for 2.5 h. After stirring evenly, the seedling nutrient solution is obtained.

[0079] Compared with Example 1, this comparative example adds pretreated attapulgite to the nanonutrient element solution.

[0080] The seedling nutrient solutions prepared in Examples 1-3 and Comparative Examples 1-3 were used in a field trial in a sugarcane-growing area in Yunnan Province. The trial consisted of 7 groups: a control group, Example 1 group, Example 2 group, Example 3 group, Comparative Example 1 group, Comparative Example 2 group, and Comparative Example 3 group, with each group consisting of 1 mu (approximately 0.067 hectares). Before planting, the seedling nutrient solutions prepared in Examples 1-3 and Comparative Examples 1-3 groups were mixed with the subsoil at a ratio of 1:50. The control group was given conventional base fertilizer (NPK = 15-15-15). At the same time, the nano-nutrient solution of the present invention was sprayed on the leaves of Examples 1-3 and Comparative Examples 1-3 groups at the seedling stage and early tillering stage, with a dilution ratio of 500 times and a spraying amount of 50 L / mu each time. The control group used conventional compound fertilizer (NPK = 15-15-15) according to the local conventional fertilizer application rate. During the harvest period, 50 sugarcane plants were randomly selected from each group, and the average number of root tillers, sugarcane plant height, sugarcane sucrose content, and yield were statistically analyzed. The test results are shown in Table 1 below.

[0081] Table 1 Sugarcane growth in each group

[0082] Number of root tillers (individuals) Plant height (m) Sucrose content (%) Yield (t / mu) Blank group 5.2 2.14 14.1 7.1 Example 1 Group 8.4 2.91 16.9 9.5 Example 2 group 8.1 2.75 16.5 9.2 Example 3 Group 8.3 2.87 16.8 9.4 Comparative Example 1 7.4 2.68 16.1 8.4 Comparative Example 2 7.1 2.62 15.9 8.2 Comparative Example 3 Groups 6.5 2.53 15.3 7.7

[0083] As can be seen from Table 1 above, the seedling nutrient solution prepared by this invention increases the number of root tillers by 50%-60% compared with the control group, which can effectively improve the yield and sucrose content of sugarcane and has good application prospects.

[0084] The above description is a further detailed explanation of the present invention in conjunction with specific implementation examples. It should not be considered that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, several simple deductions or substitutions can be made without departing from the concept of the present invention, and all such deductions or substitutions should be considered to fall within the protection scope of the present invention.

[0085] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing a seedling nutrient solution to improve the tillering ability of sugarcane roots, characterized in that, Includes the following steps: S1. Add attapulgite to nitric acid solution for impregnation treatment. After treatment, filter and add the solid product to ethanol aqueous solution. Then add γ-glycidoxypropyltrimethoxysilane and stir to react to obtain pretreated attapulgite. S2. Add the pretreated attapulgite to N,N-dimethylformamide, then add 4-imidazolium acrylic acid and N,N-dimethylcyclohexylamine, and heat the reaction. After the reaction is completed, filter, wash and dry to obtain organic attapulgite. Add the organic attapulgite to deionized water, then add oleyl alcohol polyoxyethylene ether and potassium persulfate, and carry out a constant temperature reaction to obtain modified attapulgite. S3. Add zinc sulfate, copper nitrate, and potassium dihydrogen phosphate to deionized water and stir until homogeneous to obtain a composite element solution; then add modified attapulgite to the composite element solution and perform ultrasonic treatment to obtain a nano-nutrient element solution. S4. Mix sugarcane bagasse and soybean cake evenly to obtain a mixture. Then add Bacillus subtilis and cellulase, adjust the moisture content, and carry out fermentation. After fermentation, a biosynthesized organic slurry is obtained. S5. Mix the nano-nutrient element solution with the biosynthesized organic slurry evenly to obtain a mixture. Then add chitosan and stir. After stirring evenly, the seedling nutrient solution is obtained. In step S1, the mass ratio of the solid product to γ-glycidyl etheroxypropyltrimethoxysilane is 90-100:8-11, the mass ratio of ethanol to water is 3:1, and the stirring reaction is carried out at a temperature of 50-60℃ for 2-3 hours. In step S2, the mass ratio of the pretreated attapulgite, N,N-dimethylformamide, 4-imidazolium acrylic acid, and N,N-dimethylcyclohexylamine is 90-100:1200:12-16:2-3, and the heating reaction is carried out at a temperature of 80-90℃ for 3-4 hours.

2. The preparation method according to claim 1, characterized in that, The mass concentration of the nitric acid solution in step S1 is 15-20%, the temperature of the impregnation treatment is 30-40℃, and the time is 1-2h.

3. The preparation method according to claim 1, characterized in that, In step S2, the mass ratio of organic attapulgite, oleyl alcohol polyoxyethylene ether, and potassium persulfate is 90-100:4-5:0.3-0.5, and the isothermal reaction is carried out at a temperature of 65-75°C for 1-2 hours.

4. The preparation method according to claim 1, characterized in that, In step S3, the mass ratio of zinc sulfate, copper nitrate, potassium dihydrogen phosphate, and deionized water is 7-10:4-6:19-24:1000. The amount of modified attapulgite added is 6-8% of the mass of the composite element solution. The ultrasonic treatment frequency is 30-40kHz, the power is 200-250W, and the time is 30-40min.

5. The preparation method according to claim 1, characterized in that, In step S4, the mass ratio of sugarcane bagasse to soybean cake is 7-8:2-3, the amount of Bacillus subtilis added is 1-2% of the mass of the mixture, the amount of cellulase added is 2-3% of the mass of the mixture, and the moisture content is 60-70%.

6. The preparation method according to claim 1, characterized in that, The fermentation temperature in step S4 is 30-35℃, and the time is 72-96h.

7. The preparation method according to claim 1, characterized in that, In step S5, the mass ratio of the nanonutrient element solution to the biosynthetic organic slurry is 1:2-3, the amount of chitosan added is 0.4-0.7% of the mass of the mixture, the stirring rate is 700-900 r / min, and the stirring time is 2-3 h.

8. A seedling nutrient solution for improving the tillering ability of sugarcane roots, prepared by the method according to any one of claims 1-7.