A compound microbial agent and microbial fertilizer
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- YANAN KANGYIYUAN BIOTECHNOLOGY CO LTD
- Filing Date
- 2026-01-29
- Publication Date
- 2026-05-26
Smart Images
Figure CN122081111A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of microbial fertilizers, and particularly to a compound microbial agent and a microbial fertilizer. Background Technology
[0002] Microbial fertilizers have become one of the core products for the green transformation of agriculture because they can replace some chemical fertilizers, improve soil structure, and enhance the quality of agricultural products. Microbial inoculants and microbial fertilizers, through the activities of beneficial microorganisms, can fix nitrogen, solubilize phosphorus and potassium, secrete growth-promoting substances, and inhibit soil-borne diseases, thereby reducing the use of chemical fertilizers and pesticides and improving crop quality.
[0003] Existing microbial fertilizers still have some technical pain points: First, the strains lack stress resistance. Most existing strains rely on traditional mutagenesis or natural selection, and their survival rate in extreme soil environments such as high temperature, salinity, and drought is less than 30%, resulting in unstable field application effects. Second, their functions are limited. Most compound microbial agents only focus on single nutrient conversion functions such as nitrogen fixation and phosphorus solubilization, lacking synergistic effects of "promoting growth, resisting disease, and remediating soil". Third, the formulation and process are outdated. Powder and liquid formulations account for 80%, with a shelf life of less than 6 months at room temperature. Microencapsulation technology is difficult to popularize due to its high cost and low encapsulation efficiency, and the fermentation process relies on manual control, with a contamination rate of 3-5%.
[0004] Therefore, developing a compound microbial agent that is stable in formulation, multifunctional and synergistic, highly stress-resistant, and well-compatible with chemical fertilizers is of great value. Summary of the Invention
[0005] The purpose of this invention is to provide a compound microbial agent and microbial fertilizer to solve the defects of existing technologies, such as weak strain resistance, poor functional synergy, and insufficient formulation stability.
[0006] In a first aspect, the present invention provides a compound microbial inoculant, comprising the following components in parts by weight: 25-35 parts of Bacillus subtilis, 20-30 parts of Bacillus amyloliquefaciens, 15-25 parts of Paenibacillus mucilaginosus, 10-15 parts of Aspergillus niger, and 1 part of Saccharomyces cerevisiae. Saccharomyces cerevisiae 5-10 parts, Bacillus sicca inoculum ( Bacillus siamensis 4-8 portions.
[0007] As a preferred embodiment of the present invention, the total viable count of the composite microbial agent is ≥6.5×10⁻⁶. 9 CFU / g.
[0008] Secondly, the present invention also provides a microbial fertilizer comprising the following components in parts by weight: 15-20 parts of the compound microbial agent as described in any one of claims 1-2, 0.5-1.0 parts of a plant-derived stress-inducing agent, 1.0-2.0 parts of a trace element chelate, 10-15 parts of potassium dihydrogen phosphate, 40-50 parts of alkaline hydrolyzed modified tobacco powder, 15-20 parts of expanded perlite, and 10-15 parts of potassium humate.
[0009] As a preferred embodiment of the present invention, the plant-derived stress-resistance inducer is mogroside V; the trace element chelate is sodium ferric ethylenediamine di-o-hydroxyphenylacetate.
[0010] As a preferred technical solution of the present invention, the method for preparing the alkaline hydrolysis modified tobacco powder is as follows: tobacco waste is mixed with a potassium hydroxide solution with a mass concentration of 1.5~2.0% at a mass ratio of 1:8~12, treated at 65~70℃ for 2~3 hours, filtered to obtain a precipitate, washed with deionized water 2~3 times, and then dried at 50~60℃ until the moisture content is ≤10% to obtain alkaline hydrolysis modified tobacco powder.
[0011] Thirdly, the present invention also provides a method for preparing microbial fertilizer, comprising the following steps: S1. Base material preparation: The alkaline hydrolyzed modified tobacco powder is pulverized to 40-60 mesh, a compound enzyme preparation is added, and enzymatic hydrolysis is carried out at 50-55℃ for 24-36 hours to obtain enzymatically hydrolyzed tobacco powder; S2. Temperature-limited step fermentation: Enzymatically hydrolyzed tobacco powder is mixed with expanded perlite and potassium humate, and inoculated with the compound microbial agent. The moisture content is adjusted to 45-55%. Under the condition of ventilation rate of 0.3-0.5 m³ / (min·m³), staged temperature-controlled fermentation is carried out: first, fermentation is carried out at 30-35℃ for 48 hours, then fermentation is continued at 35-40℃ for 2-3 days, and finally fermentation is maintained at 40-42℃ for 1-2 days to obtain the fermentation product; S3. Functional Enhancement Mixing: Plant-derived stress inducers, trace element chelates and potassium dihydrogen phosphate are added to the fermentation products and mixed evenly to obtain functionalized materials; S4. Microencapsulation: The functionalized material is mixed evenly with a sodium alginate solution with a mass concentration of 1.0~3.0% at a mass ratio of 1:4~6. The mixture is then added dropwise to a calcium chloride solution with a mass concentration of 1.5~3.0% through a dropping device to form microcapsule precursors. The microcapsule precursors are filtered, washed with deionized water, and then immersed in a chitosan acetate solution with a mass concentration of 1.5~2.0% for 10~20 minutes. After that, they are drained and dried at low temperature to obtain the finished microcapsule bacterial fertilizer granules.
[0012] As a preferred embodiment of the present invention, the compound enzyme preparation is obtained by mixing cellulase and lignin peroxidase in a mass ratio of 3:1, and the amount added is 0.5-0.8% of the dry weight of the alkaline hydrolyzed modified tobacco powder; The low-temperature drying temperature is 35~45℃, and the product moisture content is dried to ≤12%.
[0013] Compared with the prior art, the beneficial effects of the present invention are: 1. The compound microbial agent of this invention integrates bacteria, fungi, and yeast, providing comprehensive functional coverage. Bacillus subtilis and Bacillus amyloliquefaciens serve as the core, effectively inhibiting soil-borne diseases and promoting growth. Bacillus spp. and Aspergillus niger work synergistically to activate fixed potassium, phosphorus, and other mineral nutrients in the soil, improving fertilizer utilization. Various active substances produced by the metabolism of Saccharomyces cerevisiae further stimulate plant root development. Bacillus sicca enhances the competitive inhibition of pathogens by the microbial community. The agent has a high total viable count, strong activity, and long-lasting effect. It is suitable for temperature-limited step fermentation processes, enabling efficient reproduction in the substrate and promoting the release of nutrients from raw materials such as tobacco dust. Simultaneously, it works synergistically with functional factors to provide plants with both nutritional supply and disease control, contributing to healthy plant growth.
[0014] 2. This invention innovatively uses cigarette waste from the cigarette industry as the main carrier material. Its naturally occurring nicotine content helps inhibit soil-borne pathogenic fungi. Through alkaline hydrolysis, it effectively breaks down the stubborn structure of the cigarette waste, improving its biodegradability. During degradation, it may produce substances with plant growth-regulating activity, such as nicotinic acid. Simultaneously, cigarette waste itself is rich in potassium, organic matter, and trace elements. After alkaline and enzymatic hydrolysis, it effectively releases nutrients and forms a porous structure, significantly improving its water retention, air permeability, and adsorption properties, providing an excellent habitat for complex microorganisms. Furthermore, the use of cigarette waste achieves resource recycling, transforming difficult-to-treat solid waste into high-value-added products, reducing environmental pressure and disposal costs, turning waste into treasure, significantly reducing the raw material cost of microbial fertilizers, and endowing the product with unique soil-improving potential, aligning with the direction of green agriculture and sustainable development.
[0015] 3. In the preparation of the microbial fertilizer of this invention, the enzymatic hydrolysis stage utilizes the synergistic effect of cellulase and lignin peroxidase to deeply degrade the stubborn lignocellulose structure in tobacco dust, transforming it into a soluble carbon source and porous carrier easily utilized by microorganisms, laying an efficient material foundation for subsequent fermentation. The temperature-limited gradient fermentation employs a three-step temperature control, achieving precise niche regulation of the complex microbial community. The initial low-temperature stage ensures the simultaneous colonization and propagation of all functional microorganisms such as Aspergillus niger and yeast; the mesophilic stage enhances the metabolic activity of dominant bacteria such as Bacillus, accelerating the conversion of organic materials; and the final short-term high-temperature stage promotes the formation of functional spores and stabilizes the material. This process maximizes the preservation of microbial diversity, activity, and functional synergy. Through sodium alginate-calcium chloride gel solidification and chitosan coating, fermentation products and functional factors are encapsulated to form protective particles. This structure not only effectively buffers external environmental stress and significantly improves the storage stability of the microbial agent and active ingredients, but also achieves controlled slow release and targeted delivery in the soil, thereby extending the fertilizer effect cycle.
[0016] 4. This invention achieves a synergistic upgrade from "nutrient supply" to "stress resistance enhancement" and "efficient nutrient utilization" by adding two functional factors: mogroside V and ethylenediamine di-o-hydroxyphenyl ferric acetate sodium (EDDHA-FeNa). Mogroside V, as a highly efficient plant-derived stress resistance inducer, can systematically activate the crop's own defense responses against disease, drought, and salt, essentially providing the crop with an "immune vaccine," making it more resilient to biotic and abiotic stresses. EDDHA-FeNa provides stable and available iron, which is not only essential for key physiological processes such as chlorophyll synthesis in plants but also serves as a cofactor for various microbial enzymes, supporting the metabolism and reproductive activity of microorganisms in the compound inoculant. The combination of these two factors with the multifunctional microbial inoculant forms a dual protection against biotic and abiotic stresses and improves nutrient utilization efficiency, achieving multi-level functional enhancement from improving soil microecology to directly strengthening plant health. Attached Figure Description
[0017] Figure 1 This is a flowchart illustrating the preparation process of the microbial fertilizer of the present invention. Detailed Implementation
[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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 skilled in the art without creative effort are within the scope of protection of the present invention.
[0019] Current applications of microbial fertilizers generally suffer from numerous technical challenges, such as poor stability of live bacteria. Most microbial fertilizer strains are susceptible to environmental factors like soil pH and temperature, resulting in short survival periods after application and rapid decline in the number of effective live bacteria, hindering sustained fertilizer efficacy. Nutrient release is uneven; conventional microbial fertilizers have low nutrient conversion efficiency, leading to insufficient nutrient supply in the early stages and nutrient loss and waste in the later stages. Their stress resistance function is limited, mostly focusing only on nutrient supply, with limited impact on improving plant resistance to cold, drought, and disease. Meanwhile, the cigarette industry generates large quantities of tobacco waste that is difficult to treat. Traditional disposal or incineration not only wastes resources but also easily causes soil and air pollution, highlighting the urgent need to improve its resource utilization rate. Based on these industry pain points, this invention specifically develops a suitable compound microbial agent, modified tobacco substrate, and precise processing technology, aiming to address existing technological shortcomings and achieve the dual goals of waste resource utilization and upgraded microbial fertilizer efficiency.
[0020] The six microbial agents in this invention are not simply superimposed, but carefully designed based on the principle of "functional complementarity and niche synergy." Among them, *Bacillus subtilis*, *Bacillus amyloliquefaciens*, and *Bacillus sicca* constitute the core group for disease biological control; *Bacillus spp.* and *Aspergillus niger* constitute the inorganic nutrient (potassium, phosphorus) activating functional group, and their organic acid secretion has a synergistic effect; *Saccharomyces cerevisiae* acts as a metabolic promoter and signaling stimulant, providing nutritional support to the entire microbial community and stimulating plant responses. The specific weight ratio of this invention (e.g., 25-35 parts of *Bacillus subtilis* as the dominant agent and 5-10 parts of *Saccharomyces cerevisiae* as the auxiliary agent) was finally determined through verification of disease control effects. Experimental data show that the microbial community under this ratio exhibits moderate growth competition during co-cultivation and can significantly improve the colonization ability of the compound microbial agent in the soil, the total yield of functional substances (such as organic acids and antimicrobial lipopeptides), and the comprehensive effect on crop growth promotion and stress resistance, proving its synergistic effect of "1+1>2".
[0021] Tobacco waste is treated with dilute alkali (KOH) under gentle heating conditions to break the ester and ether bonds between lignin and cellulose / hemicellulose, disrupting its dense structure and increasing its specific surface area and reactivity. Simultaneously, alkali treatment effectively degrades alkaloids such as nicotine in tobacco waste that inhibit microbial growth, converting them into harmless or beneficial components such as nicotinic acid salts and low-toxicity degradation products. This eliminates carrier toxicity and creates a suitable environment for subsequent fermentation with compound microbial agents. The washing step removes excess alkali and some water-soluble inhibitors, creating a safe and suitable physicochemical environment for subsequent microbial fermentation.
[0022] Enzymatic pretreatment (cellulase and lignin peroxidase) further degrades the loose lignocellulose after alkaline hydrolysis into fermentable sugars, providing a directly usable carbon source for microorganisms. Temperature-limited step fermentation is the core innovation of this process. Its temperature curve is scientifically designed based on the optimal growth temperature of each member in the compound microbial agent: The first stage (30~35℃) is the "whole-cell activation period," ensuring that Aspergillus niger, Saccharomyces cerevisiae, and all Bacillus spores can initiate growth effectively, laying the foundation for the community; the second stage (35~40℃, 2~3 days) is the "main metabolic period," suitable for the vigorous proliferation of most Bacillus spores and the secretion of functional metabolites, accelerating material conversion; the third stage (40~42℃, 1~2 days) is the "spore induction and stabilization period," promoting the formation of highly resistant spores by Bacillus subtilis, Amyloliquefaciens, and other Bacillus spores, while also helping to kill heat-sensitive bacteria and improve product purity and stability.
[0023] By employing a sodium alginate-calcium chloride ionogel method to form primary microcapsules, active substances can be gently encapsulated within a hydrogel network. Subsequent impregnation with chitosan acetate solution forms a positively charged coating on the microcapsule surface through electrostatic interactions. This coating is pH-responsive and further enhances the density and mechanical strength of the capsule wall. This structure effectively isolates external stresses such as light, heat, and drought, preventing premature inactivation of the bacteria and enabling the slow release of nutrients and inoculants into the soil.
[0024] In addition, plant-derived stress-resistance inducers (monk fruit saponin V) can induce the expression of plant stress-resistance genes. In synergy with trace element chelates (ethylenediamine di-o-hydroxyphenyl sodium ferric acetate), they can improve the absorption and utilization rate of iron in plants and alleviate iron deficiency stress. When combined with compound microbial agents, potassium dihydrogen phosphate, potassium humate and other nutrients, they can ensure a balanced supply of nutrients to plants and strengthen plant stress resistance. At the same time, the metabolic activities of the microbial community can further promote nutrient transformation and release, forming a closed-loop synergistic effect of "microbial community activation-nutrient supply-stress enhancement", which significantly improves the comprehensive effectiveness of microbial fertilizer.
[0025] like Figure 1As shown, a method for preparing a microbial fertilizer includes the following steps: S1. Substrate preparation: Alkali-hydrolyzed modified tobacco powder is pulverized to 40-60 mesh, a compound enzyme preparation is added, and enzymatic hydrolysis is carried out at 50-55℃ for 24-36 hours to obtain enzymatically hydrolyzed tobacco powder; S2. Temperature-controlled step fermentation: The enzymatically hydrolyzed tobacco powder is mixed with expanded perlite and potassium humate, inoculated with the compound microbial agent, and the moisture content is adjusted to 45%-55%. Under the condition of a ventilation rate of 0.3-0.5 m³ / (min·m³), a staged temperature-controlled fermentation is carried out: first, fermentation is carried out at 30-35℃ for 48 hours, then fermentation is continued at 35-40℃ for 2-3 days, and finally fermentation is maintained at 40-42℃ for 1-2 days. S3. Functional Enhancement Mixing: Add plant-derived stress-inducing agents, trace element chelates, and potassium dihydrogen phosphate to the fermentation products, mix evenly, and obtain functionalized materials; S4. Microencapsulation: Mix the functionalized materials with a sodium alginate solution with a mass concentration of 1.0~3.0% at a mass ratio of 1:4~6 evenly, and add it dropwise into a calcium chloride solution with a mass concentration of 1.5~3.0% through a dropping device to form microcapsule primary products. Filter the microcapsule primary products, wash them with deionized water, and then soak them in a chitosan acetate solution with a mass concentration of 1.5~2.0% for 10~20 minutes. Then drain and dry at low temperature to obtain microcapsule bacterial fertilizer granules.
[0026] All raw materials used in this invention are commercially available.
[0027] Example 1
[0028] A compound microbial agent comprises the following components in parts by weight: 35 parts of Bacillus subtilis agent, 30 parts of Bacillus amyloliquefaciens agent, 25 parts of Bacillus spp. agent, 15 parts of Aspergillus niger agent, 10 parts of Saccharomyces cerevisiae agent, and 8 parts of Bacillus sicca agent. The total viable count of the compound microbial agent is ≥6.5 × 10⁻⁶. 9 CFU / g.
[0029] A microbial fertilizer comprises the following components in parts by weight: 20 parts of the compound microbial agent as described in any one of claims 1 to 2, 1.0 part of plant-derived stress-inducing agent (monk fruit saponin V), 2.0 parts of trace element chelate (ethylenediamine di-o-hydroxyphenyl ferric sodium acetate), 15 parts of potassium dihydrogen phosphate, 50 parts of alkaline hydrolyzed modified tobacco powder, 20 parts of expanded perlite, and 15 parts of potassium humate.
[0030] A method for preparing a microbial fertilizer includes the following steps: S1. Preparation of base material: The tobacco waste and the 2.0% potassium hydroxide solution were mixed evenly at a mass ratio of 1:12, treated at 70℃ for 3 hours, filtered to obtain precipitate, washed 3 times with deionized water, and then dried at 60℃ until the moisture content was ≤10% to obtain alkaline hydrolysis modified tobacco.
[0031] The alkaline hydrolyzed modified tobacco powder was pulverized to 60 mesh, and a compound enzyme preparation (cellulase and lignin peroxidase were mixed in a mass ratio of 3:1, and the amount added was 0.8% of the dry weight of the alkaline hydrolyzed modified tobacco powder) was added. The mixture was enzymatically hydrolyzed at 55℃ for 36 hours to obtain enzymatically hydrolyzed tobacco powder. S2. Temperature-limited step fermentation: Enzymatically hydrolyzed tobacco powder is mixed with expanded perlite and potassium humate, inoculated with the compound microbial agent, and the moisture content is adjusted to 55%. Under the condition of ventilation rate of 0.5 m³ / (min·m³), staged temperature-controlled fermentation is carried out: first fermentation at 35℃ for 48 hours, then fermentation at 40℃ for 3 days, and finally fermentation at 42℃ for 2 days to obtain the fermentation product; S3. Functional Enhancement Mixing: Plant-derived stress inducers, trace element chelates and potassium dihydrogen phosphate are added to the fermentation products and mixed evenly to obtain functionalized materials; S4. Microencapsulation: The functionalized material is mixed evenly with a 3.0% sodium alginate solution at a mass ratio of 1:6. The mixture is then added dropwise to a 3.0% calcium chloride solution to form microcapsule precursors. The microcapsule precursors are filtered, washed with deionized water, and then immersed in a 2.0% chitosan acetate solution for 20 minutes. After draining, the product is dried at a low temperature of 45℃ until the moisture content is ≤12%, thus obtaining the finished microcapsule microbial fertilizer granules.
[0032] Example 2
[0033] A compound microbial agent comprises the following components in parts by weight: 25 parts of Bacillus subtilis agent, 20 parts of Bacillus amyloliquefaciens agent, 15 parts of Bacillus thuringiensis agent, 10 parts of Aspergillus niger agent, 5 parts of Saccharomyces cerevisiae agent, and 4 parts of Bacillus sicca agent. The total viable count of the compound microbial agent is ≥6.5 × 10⁻⁶. 9 CFU / g.
[0034] A microbial fertilizer comprises the following components in parts by weight: 15 parts of the compound microbial agent as described in any one of claims 1 to 2, 0.5 parts of plant-derived stress-inducing agent (monk fruit saponin V), 1.0 part of trace element chelate (ethylenediamine di-o-hydroxyphenyl ferric sodium acetate), 10 parts of potassium dihydrogen phosphate, 40 parts of alkaline hydrolyzed modified tobacco powder, 15 parts of expanded perlite, and 10 parts of potassium humate.
[0035] A method for preparing a microbial fertilizer includes the following steps: S1. Preparation of base material: The waste tobacco powder is mixed with a 1.5% potassium hydroxide solution at a mass ratio of 1:8, treated at 65℃ for 2 hours, filtered to obtain a precipitate, washed twice with deionized water, and then dried at 50℃ until the moisture content is ≤10% to obtain alkaline hydrolysis modified tobacco powder.
[0036] The alkaline hydrolyzed modified tobacco powder was pulverized to 40 mesh, and a compound enzyme preparation (cellulase and lignin peroxidase were mixed in a mass ratio of 3:1, and the amount added was 0.5% of the dry weight of the alkaline hydrolyzed modified tobacco powder) was added. The mixture was enzymatically hydrolyzed at 50℃ for 24 hours to obtain enzymatically hydrolyzed tobacco powder. S2. Temperature-limited step fermentation: Enzymatically hydrolyzed tobacco powder is mixed with expanded perlite and potassium humate, inoculated with the compound microbial agent, and the moisture content is adjusted to 45%. Under the condition of ventilation rate of 0.3 m³ / (min·m³), staged temperature-controlled fermentation is carried out: first fermentation at 30℃ for 48 hours, then fermentation at 35℃ for 2 days, and finally fermentation at 40℃ for 1 day to obtain the fermentation product; S3. Functional Enhancement Mixing: Plant-derived stress inducers, trace element chelates and potassium dihydrogen phosphate are added to the fermentation products and mixed evenly to obtain functionalized materials; S4. Microencapsulation: The functionalized material is mixed evenly with a 1.0% sodium alginate solution at a mass ratio of 1:4. The mixture is then added dropwise to a 1.5% calcium chloride solution to form microcapsule precursors. The microcapsule precursors are filtered, washed with deionized water, and then immersed in a 1.5% chitosan acetate solution for 10 minutes. After draining, the product is dried at a low temperature of 35°C until the moisture content is ≤12%, thus obtaining the finished microcapsule microbial fertilizer granules.
[0037] Example 3
[0038] A compound microbial agent comprises the following components in parts by weight: 30 parts of Bacillus subtilis agent, 25 parts of Bacillus amyloliquefaciens agent, 20 parts of Bacillus spp. agent, 12.5 parts of Aspergillus niger agent, 7.5 parts of Saccharomyces cerevisiae agent, and 6 parts of Bacillus sicca agent. The total viable count of the compound microbial agent is ≥6.5 × 10⁻⁶. 9 CFU / g.
[0039] A microbial fertilizer comprises the following components in parts by weight: 17.5 parts of the compound microbial agent as described in any one of claims 1 to 2, 0.7 parts of plant-derived stress-inducing agent (monk fruit saponin V), 1.5 parts of trace element chelate (ethylenediamine di-o-hydroxyphenyl ferric sodium acetate), 12.5 parts of potassium dihydrogen phosphate, 45 parts of alkaline hydrolyzed modified tobacco powder, 17.5 parts of expanded perlite, and 12.5 parts of potassium humate.
[0040] A method for preparing a microbial fertilizer includes the following steps: S1. Preparation of base material: The tobacco waste and the 1.7% potassium hydroxide solution were mixed evenly at a mass ratio of 1:10, treated at 67℃ for 2.5h, filtered to obtain precipitate, washed 3 times with deionized water, and then dried at 55℃ until the moisture content was ≤10% to obtain alkaline hydrolysis modified tobacco.
[0041] The alkaline hydrolyzed modified tobacco powder was pulverized to 50 mesh, and a compound enzyme preparation (cellulase and lignin peroxidase were mixed in a mass ratio of 3:1, and the amount added was 0.6% of the dry weight of the alkaline hydrolyzed modified tobacco powder) was added. The mixture was enzymatically hydrolyzed at 52℃ for 30 hours to obtain enzymatically hydrolyzed tobacco powder. S2. Temperature-limited stepped fermentation: Enzymatically hydrolyzed tobacco powder is mixed with expanded perlite and potassium humate, inoculated with the compound microbial agent, and the moisture content is adjusted to 50%. Under the condition of a ventilation rate of 0.4 m³ / (min·m³), staged temperature-controlled fermentation is carried out: first, fermentation is carried out at 32℃ for 48 hours, then fermentation is continued at 37℃ for 2.5 days, and finally fermentation is maintained at 41℃ for 1.5 days to obtain the fermentation product; S3. Functional Enhancement Mixing: Plant-derived stress inducers, trace element chelates and potassium dihydrogen phosphate are added to the fermentation products and mixed evenly to obtain functionalized materials; S4. Microencapsulation: The functionalized material is mixed evenly with a 2.0% sodium alginate solution at a mass ratio of 1:5. The mixture is then added dropwise to a 2.2% calcium chloride solution to form microcapsule precursors. The microcapsule precursors are filtered, washed with deionized water, and then immersed in a 1.7% chitosan acetate solution for 15 minutes. After draining, the product is dried at a low temperature of 40℃ until the moisture content is ≤12%, thus obtaining the finished microcapsule microbial fertilizer granules.
[0042] Comparative Example 1: The difference from Example 1 is that the compound microbial agent is removed.
[0043] Comparative Example 2: The difference from Example 1 is that the tobacco waste is added directly without undergoing alkaline hydrolysis modification.
[0044] Comparative Example 3: The difference from Example 1 is that the alkaline hydrolysis modified tobacco powder is removed.
[0045] Comparative Example 4: The difference from Example 1 is that the staged temperature-controlled fermentation in S2 is replaced with fermentation at 40~42℃ for 3~4 days.
[0046] Comparative Example 5: The difference from Example 1 is that the S4 microencapsulation step is removed, and the microbial fertilizer is obtained by direct drying after fermentation.
[0047] Comparative Example 6: The difference from Example 1 is that the chitosan acetate solution treatment step in S4 is removed.
[0048] The microbial fertilizers prepared in Examples 1, 2, and 3 and Comparative Examples 1, 2, 3, 4, 5, and 6 were tested.
[0049] Experimental fields were selected under identical soil conditions. Microbial fertilizers from Examples 1, 2, and 3, and Comparative Examples 1, 2, 3, 4, 5, and 6 were applied in equal amounts to corn plants. Fertilization was performed three times during the cultivation process: the first application as basal fertilizer, and the second and third as topdressing. Each application was at a standard rate of 150 kg / mu. A control group was also set up, using commercially available imported compound microbial fertilizer. Only the type of fertilizer differed; all other management and seedling cultivation were identical. Growth and disease index were statistically analyzed compared to the control group for both examples and comparative examples. Each treatment was replicated three times, and the average value was taken to calculate the effect of each fertilizer application. The experimental results are shown in Table 1.
[0050] Table 1: Effects of microbial fertilizers on corn
[0051] As can be seen from Table 1, the microbial fertilizer prepared in the embodiments of the present invention has a significant effect on promoting root growth and increasing yield in corn. It can significantly reduce the incidence of soil-borne diseases and soil cadmium content, and increase soil organic matter content. The overall effect is significantly better than that of the comparative proportions and commercially available imported compound microbial fertilizers.
[0052] The four core elements of this product—compound microbial inoculants, alkaline-hydrolyzed modified tobacco dust, staged temperature-controlled fermentation, and microencapsulation—work synergistically. The compound microbial inoculants, through the complementary functions of multiple strains, promote crop root growth, inhibit the reproduction of soil-borne pathogens, activate soil nutrients, and increase soil organic matter content and crop yield. Alkaline-hydrolyzed modified tobacco dust realizes the resource utilization of waste, providing a high-quality carbon source for microorganisms, improving soil structure, enhancing soil cadmium adsorption and fixation capacity, and helping to reduce soil cadmium content and increase organic matter. Staged temperature-controlled fermentation, adapted to the growth characteristics of the strains, ensures high viable bacterial counts and metabolite secretion, enhances nutrient conversion efficiency, and further improves the effects of promoting growth, preventing disease, and reducing cadmium. Microencapsulation protects active ingredients from environmental stress, enabling slow release of inoculants and nutrients, extending the duration of fertilizer effectiveness, steadily increasing crop yield, reducing disease incidence, and ensuring long-term stable optimization of various indicators, comprehensively promoting crop growth and improving soil quality.
[0053] In summary, the compound microbial inoculant and microbial fertilizer prepared by this invention have novel strain combinations, significant synergistic effects, strong environmental adaptability, and multiple functions such as promoting growth, resisting disease, improving soil and enhancing crop stress resistance.
[0054] The above are merely specific embodiments of the present invention, but the technical features of the present invention are not limited thereto. Any invention based on the present invention, aimed at solving essentially the same technical problem and achieving essentially the same technical effect, may also be applied.
Claims
1. A compound microbial agent, characterized in that, It consists of the following components in parts by weight: 25-35 parts of Bacillus subtilis inoculant, 20-30 parts of Bacillus amyloliquefaciens inoculant, 15-25 parts of Bacillus jellyoidus inoculant, 10-15 parts of Aspergillus niger inoculant, 5-10 parts of Saccharomyces cerevisiae inoculant, and 4-8 parts of Bacillus sicca inoculant.
2. The compound microbial agent according to claim 1, characterized in that, The total viable count of the compound microbial agent is ≥6.5×10⁻⁶. 9 CFU / g.
3. A microbial fertilizer, characterized in that, The product comprises the following components in parts by weight: 15-20 parts of the compound microbial agent as described in any one of claims 1-2, 0.5-1.0 parts of the plant-derived stress-inducing agent, 1.0-2.0 parts of the trace element chelate, 10-15 parts of potassium dihydrogen phosphate, 40-50 parts of alkaline hydrolyzed modified tobacco powder, 15-20 parts of expanded perlite, and 10-15 parts of potassium humate.
4. The microbial fertilizer according to claim 3, characterized in that, The plant-derived stress-resistance inducer is mogroside V; the trace element chelate is sodium ferric ethylenediamine di-o-hydroxyphenylacetate.
5. A microbial fertilizer according to claim 3, characterized in that, The method for preparing the alkaline hydrolysis modified tobacco powder is as follows: tobacco waste is mixed with a potassium hydroxide solution with a mass concentration of 1.5~2.0% at a mass ratio of 1:8~12, treated at 65~70℃ for 2~3 hours, filtered to obtain a precipitate, washed with deionized water 2~3 times, and then dried at 50~60℃ until the moisture content is ≤10% to obtain alkaline hydrolysis modified tobacco powder.
6. A method for preparing microbial fertilizer as described in any one of claims 4 to 5, characterized in that, Includes the following steps: S1. Base material preparation: The alkaline hydrolyzed modified tobacco powder is pulverized to 40-60 mesh, a compound enzyme preparation is added, and enzymatic hydrolysis is carried out at 50-55℃ for 24-36 hours to obtain enzymatically hydrolyzed tobacco powder; S2. Temperature-limited step fermentation: Enzymatically hydrolyzed tobacco powder is mixed with expanded perlite and potassium humate, and inoculated with the compound microbial agent. The moisture content is adjusted to 45-55%. Under the condition of ventilation rate of 0.3-0.5 m³ / (min·m³), staged temperature-controlled fermentation is carried out: first, fermentation is carried out at 30-35℃ for 48 hours, then fermentation is continued at 35-40℃ for 2-3 days, and finally fermentation is maintained at 40-42℃ for 1-2 days to obtain the fermentation product; S3. Functional Enhancement Mixing: Plant-derived stress inducers, trace element chelates and potassium dihydrogen phosphate are added to the fermentation products and mixed evenly to obtain functionalized materials; S4. Microencapsulation: The functionalized material is mixed evenly with a sodium alginate solution with a mass concentration of 1.0~3.0% at a mass ratio of 1:4~6. The mixture is then added dropwise to a calcium chloride solution with a mass concentration of 1.5~3.0% through a dropping device to form microcapsule precursors. The microcapsule precursors are filtered, washed with deionized water, and then immersed in a chitosan acetate solution with a mass concentration of 1.5~2.0% for 10~20 minutes. After that, they are drained and dried at low temperature to obtain the finished microcapsule bacterial fertilizer granules.
7. The method for preparing a microbial fertilizer according to claim 6, characterized in that: The compound enzyme preparation is obtained by mixing cellulase and lignin peroxidase in a mass ratio of 3:1, and the amount added is 0.5-0.8% of the dry weight of the alkaline hydrolyzed modified tobacco powder; The low-temperature drying temperature is 35~45℃, and the product moisture content is dried to ≤12%.