Anti-reversal growth promoting organic fertilizer, preparation method and application thereof

Abstract

The application provides an anti-stress and growth-promoting organic fertilizer and a preparation method and application thereof, and relates to the technical field of organic fertilizer.The anti-stress and growth-promoting organic fertilizer comprises the following components: mature organic matter, biochar, plant extract, oligosaccharide, mineral substance, microbial inoculum and binder.The plant extract is composed of poplar bark extract and moringa extract, the poplar bark is extracted by ethanol ultrasonic combined with low eutectic solvent in sections, and the moringa root is obtained by anaerobic fermentation of bacillus and plant lactobacillus.The application improves the colonization rate of functional bacteria in saline-alkali environment by using the porous carrier of biochar, and improves the soil aggregate structure by using organic matter;the plant extract activates the crop system resistance and promotes lateral root growth, and the oligosaccharide optimizes the rhizosphere microecology.The fertilizer can significantly reduce the pH and salt content of saline-alkali soil, improve the soil porosity, improve the cucumber root activity and endogenous auxin content, effectively alleviate the salt stress, and realize the quality improvement and yield increase of crops.

Description

Technical Field

[0001] This invention relates to the field of organic fertilizer technology, specifically to a stress-resistant and growth-promoting organic fertilizer, its preparation method, and its application. Background Technology

[0002] Saline-alkali land suffers from soil salinization, compaction, and pH imbalance. Long-term excessive application of chemical fertilizers leads to soil organic matter depletion, rhizosphere microecological disorder, and hindered root nutrient absorption. This results in crop yellowing, increased incidence of soil-borne diseases, and weak stress resistance, restricting stable yields and quality improvement of fruits and vegetables. Currently available conventional bio-organic fertilizers have limited functions, often focusing only on supplementing organic matter or solely on inhibiting bacteria, making it difficult to simultaneously achieve synergistic effects of soil improvement, root growth promotion, and crop stress resistance induction.

[0003] Existing fertilizer products suffer from several technical shortcomings: First, functional microorganisms lack efficient porous carrier protection, resulting in low colonization rates in saline-alkali and arid environments, and unstable nitrogen fixation, phosphorus solubilization, and disease suppression effects. Second, relying solely on organic matter to improve soil lacks active induced resistance components that can directly activate plant systemic resistance, failing to enhance crop tolerance to salinity and disease resistance from an endogenous level. Third, the nutrient supply system is incomplete, lacking fast-acting active nutrients such as small molecule peptides and oligosaccharides, leading to slow root absorption and significant crop growth decline under adverse conditions. Fourth, the compound formulation lacks synergistic design, making it difficult to simultaneously achieve multiple pathways of action, including soil pH regulation, breaking up compaction, activating micronutrients, and regulating plant immunity.

[0004] Traditional fertilizers can only provide nutrients in one direction or mildly suppress disease, and have drawbacks such as long improvement cycles, weak stress resistance, and limited yield increases. Therefore, there is an urgent need to develop a stress-resistant and growth-promoting organic fertilizer that integrates soil remediation, microbial colonization and protection, plant immune activation, and fast-acting organic nutrient supply. Summary of the Invention

[0005] The purpose of this invention is to provide a stress-resistant and growth-promoting organic fertilizer, its preparation method, and its application. The organic fertilizer provided by this invention can simultaneously improve saline-alkali soil, enhance crop stress resistance, and achieve improved quality and increased yield.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a stress-resistant and growth-promoting organic fertilizer, comprising the following raw materials in parts by weight: 40-60 parts of decomposed organic matter, 10-20 parts of biochar, 2-8 parts of plant-derived extract, 1-5 parts of oligosaccharides, 2-6 parts of minerals, 0.5-3 parts of microbial inoculant, and 1-4 parts of binder; wherein the plant-derived extract is composed of poplar bark extract and moringa extract in a weight ratio of 1:(0.8-1.2).

[0007] Preferably, the decomposed organic matter is two or more of the following: decomposed cow dung, decomposed earthworm castings, decomposed straw, and decomposed peat.

[0008] Preferably, the method for preparing the poplar bark extract includes: pulverizing poplar bark and mixing it with an ethanol solution, ultrasonically extracting, filtering, concentrating the filtrate, drying to obtain an ethanol extract, mixing the filter residue with a eutectic solvent, heating and extracting, filtering, mixing the filtrate with water, purifying it through a macroporous resin, drying, and mixing it with the ethanol extract to obtain the poplar bark extract; the method for preparing the eutectic solvent includes: mixing choline chloride and citric acid at a molar ratio of 1:(0.8-1.2), heating, and mixing with water to obtain the eutectic solvent.

[0009] More preferably, the volume fraction of the ethanol solution is 65%-75%; the material-to-liquid ratio of the ultrasonic extraction is 1:(10-15)g / mL, the temperature is 50-60℃, the frequency is 30-40kHz, and the time is 25-35min.

[0010] More preferably, the mass-to-volume ratio of the filter residue to the eutectic solvent is 1:(20-30)g / mL, the heating extraction temperature is 75-85℃, and the time is 30-40min.

[0011] Preferably, the method for preparing the moringa extract includes: crushing moringa roots, mixing them with glucose and water, sterilizing them to obtain a fermentation slurry, inoculating it with compound microorganisms for anaerobic fermentation, filtering it, concentrating the filtrate, and drying it to obtain the moringa extract.

[0012] More preferably, the composite microorganisms consist of Bacillus and Lactobacillus plantarum in a viable count ratio of (2-4):(1-3); the inoculation amount of the composite microorganisms is (4-8)×10⁻⁶. 7 CFU / mL fermentation slurry; the fermentation temperature is 28-32℃ and the time is 48-60h.

[0013] Preferably, the microbial agent is composed of Bacillus subtilis and Bacillus belye.

[0014] The present invention also provides a method for preparing the above-mentioned stress-resistant and growth-promoting organic fertilizer, comprising: mixing decomposed organic matter, biochar and minerals to obtain a basic mixture, then mixing it sequentially with oligosaccharides, plant-derived extracts, binders and microbial agents, granulating and drying to obtain the stress-resistant and growth-promoting organic fertilizer.

[0015] This invention also provides an application of the above-mentioned stress-resistant and growth-promoting organic fertilizer in the preparation of fertilizers for improving saline-alkali soil and increasing yield.

[0016] The present invention has the following beneficial effects: This invention synergistically enhances crop resistance in saline-alkali soils through the combination of poplar bark extract and moringa extract. Poplar bark is extracted in two phases using alcohol and a low-melting-point solvent, activating acquired resistance and reducing oxidative damage to cell membranes. Moringa extract, through specific anaerobic fermentation with Bacillus and Lactobacillus plantarum, is rich in various active components that inhibit the reproduction of rhizosphere pathogens and root-knot nematodes while stimulating root growth; thus, it induces defense and promotes growth.

[0017] This invention uses chitosan oligosaccharides and seaweed oligosaccharides as fast-acting active nutrient components, which have the effects of signal induction and resistance, rhizosphere microbiota regulation, and direct growth promotion. Oligosaccharides can be directly absorbed by the roots, induce the synthesis of phytoalexins and chitinases, and enhance the defense against fungal diseases; at the same time, they selectively proliferate beneficial Bacillus, optimize the rhizosphere microecology, and directly stimulate the synthesis of root auxins.

[0018] This invention utilizes biochar as a porous carrier for functional microorganisms and a salt-alkali buffering medium to synergistically improve the overall physical and chemical properties of soil through the decomposition of organic matter. Biochar is rich in carboxyl and phenolic hydroxyl groups to neutralize alkalinity and chelate salt ions, while its porous structure provides a colonization microenvironment for Bacillus subtilis / Bellesium spp.; the decomposed organic matter promotes aggregate formation and alleviates soil compaction.

[0019] This invention integrates multiple pathways of action, including the protection of microbial communities by physical carriers, activation of crop biological immunity, and supply of fast-acting organic nutrients. It overcomes the shortcomings of traditional organic fertilizers, such as their single function and long cycle of saline-alkali soil improvement, and achieves a triple synergistic effect of saline-alkali soil remediation, root growth promotion, and crop stress resistance induction, thus possessing outstanding economic and ecological value. Detailed Implementation

[0020] This invention provides a stress-resistant and growth-promoting organic fertilizer, comprising the following raw materials in parts by weight: 40-60 parts of decomposed organic matter, 10-20 parts of biochar, 2-8 parts of plant-derived extract, 1-5 parts of oligosaccharides, 2-6 parts of minerals, 0.5-3 parts of microbial inoculant, and 1-4 parts of binder; wherein the plant-derived extract is composed of poplar bark extract and moringa extract in a weight ratio of 1:(0.8-1.2).

[0021] The decomposed organic matter described in this invention is preferably two or more of the following: decomposed cow manure, decomposed earthworm castings, decomposed straw, and decomposed peat. Decomposed organic matter is a fundamental functional component of organic fertilizer, promoting the formation of soil aggregates in saline-alkali soils, alleviating compaction, increasing permeability, and improving the rhizosphere microenvironment; it sustainably supplies carbon sources for functional microorganisms, providing an energy basis for their colonization and reproduction, and ensuring the activity of inoculants; it stimulates root cell division and elongation, improving the root system's ability to absorb water and nutrients.

[0022] The biochar described in this invention serves as a carrier for microbial communities, a salt-alkali improver, and a water and fertilizer buffer. Its porous structure can physically encapsulate microorganisms, significantly improving the survival rate of rhizosphere microbiota and ensuring the long-term effectiveness of its antibacterial and nutrient-activating functions. The surface of the biochar is rich in acidic functional groups such as carboxyl groups and phenolic hydroxyl groups, which can neutralize soil alkalinity, chelate soil salt ions, reduce soil salinity and pH, and alleviate soil compaction.

[0023] In this invention, the preferred method for preparing the poplar bark extract includes: pulverizing poplar bark and mixing it with an ethanol solution, ultrasonically extracting, filtering, concentrating the filtrate, drying to obtain an ethanol extract, mixing the filter residue with a eutectic solvent, heating for extraction, filtering, mixing the filtrate with water, purifying through a macroporous resin, drying, and mixing with the ethanol extract to obtain the poplar bark extract; the preferred method for preparing the eutectic solvent includes: mixing choline chloride and citric acid at a molar ratio of 1:(0.8-1.2), heating, and mixing with water to obtain the eutectic solvent; the preferred volume fraction of the ethanol solution is 65%-75%, more preferably 70%. The preferred material-to-liquid ratio for ultrasonic extraction is 1:(10-15)g / mL, more preferably 1:12g / mL; the preferred temperature is 50-60℃, more preferably 55℃; the preferred frequency is 30-40kHz, more preferably 35kHz; and the preferred time is 25-35min, more preferably 30min. The preferred mass-to-volume ratio of the filter residue to the eutectic solvent is 1:(20-30)g / mL, more preferably 1:25g / mL; the preferred temperature for heating extraction is 75-85℃, more preferably 80℃; and the preferred time is 30-40min, more preferably 35min.

[0024] In this invention, the preferred method for preparing the Moringa extract includes: pulverizing Moringa roots, mixing with glucose and water, sterilizing to obtain a fermentation slurry, inoculating with a complex microorganism for anaerobic fermentation, filtering, concentrating the filtrate, and drying to obtain the Moringa extract; the complex microorganism is preferably composed of Bacillus and Lactobacillus plantarum in a viable count ratio of (2-4):(1-3), more preferably 3:2; the preferred inoculation amount of the complex microorganism is (4-8)×10⁻⁶. 7 CFU / mL fermentation slurry, preferably 6×10 7 The fermentation temperature is preferably 28-32℃, more preferably 30℃, and the fermentation time is preferably 48-60h, more preferably 54h.

[0025] The plant-derived extracts described in this invention are important immune-inducing components in fertilizers. Poplar bark extract is rich in salicin and flavonoid polyphenols. After being absorbed by crops, it is metabolized endogenously to generate salicylic acid signaling molecules, activating acquired resistance, reducing cell membrane oxidative damage caused by salt stress, and inhibiting root rot and soil-borne fungal infections. Moringa extract contains alkaloids, isothiocyanates, and other components, which have root-promoting effects, inhibiting the reproduction of root-knot nematodes and pathogenic fungi, while supplementing natural cytokinins and stimulating the growth of lateral roots. The synergistic combination of these two components enhances the stress resistance of fruits and vegetables through signal induction and root promotion. The acidic components in moringa extract can help buffer the rhizosphere pH, alleviating the growth inhibition of plants caused by salt and alkali stress.

[0026] In this invention, the microbial agent is preferably composed of Bacillus subtilis and Bacillus belye. In the microbial agent, the viable count of Bacillus subtilis is preferably 1-1.5 billion CFU / g, more preferably 1.2 billion CFU / g, and the viable count of Bacillus belye is preferably 1.3-2 billion CFU / g, more preferably 1.7 billion CFU / g.

[0027] In this invention, the oligosaccharide is preferably composed of chitosan oligosaccharide and fucoidan oligosaccharide in a weight ratio of (5-10):(2-4), more preferably 8:3. It induces the synthesis of phytoalexins and the expression of related defense enzymes such as chitinase, reducing the incidence of soil-borne diseases in saline-alkali orchards; it can selectively proliferate beneficial Bacillus spores, inhibit the reproduction of harmful pathogens, and optimize the rhizosphere microecological balance; it can reduce the damage of salt ions to root cell membranes, improving the salt and alkali tolerance and drought resistance of fruits and vegetables; at the same time, it regulates the synthesis of root auxins, promotes the elongation of the taproot and the proliferation of fibrous roots, and expands the nutrient absorption area. When combined with plant-derived extracts, it can increase the stress resistance effect, possessing both rapid induction of resistance and long-term root promotion effects, thereby improving the yield and quality of fruits and vegetables.

[0028] In this invention, the binder is composed of bentonite and sodium carboxymethyl cellulose in a weight ratio of (3-5):(0.8-2), more preferably 4:1.

[0029] The present invention also provides a method for preparing the above-mentioned stress-resistant and growth-promoting organic fertilizer, comprising: mixing decomposed organic matter, biochar and minerals to obtain a basic mixture, then mixing it sequentially with oligosaccharides, plant-derived extracts, binders and microbial agents, granulating and drying to obtain the stress-resistant and growth-promoting organic fertilizer.

[0030] This invention also provides an application of the above-mentioned stress-resistant and growth-promoting organic fertilizer in the preparation of fertilizers for improving saline-alkali soil and increasing yield.

[0031] This invention provides a stress-resistant and growth-promoting organic fertilizer suitable for fruit and vegetable cultivation in saline-alkali land.

[0032] The application method of the stress-resistant and growth-promoting organic fertilizer of this invention is as follows: apply 80-120 kg per mu before land preparation, spread evenly, plow deeply 7-10 cm and cover with soil, mix thoroughly with the cultivated soil, and let stand for 7 days before transplanting / sowing.

[0033] Chitosan oligosaccharide is in powder form and is sourced from Shandong Jiutai Biotechnology Group Co., Ltd.; fucoidan oligosaccharide is sourced from Shaanxi Haochen Biotechnology Co., Ltd.; fructooligosaccharide is sourced from Anhui Anrui Biotechnology Co., Ltd.; soybean oligosaccharide is sourced from Anhui Anrui Biotechnology Co., Ltd.; the minerals are EDTA chelate salts containing trace elements copper, cobalt, iron, manganese, zinc, boron, magnesium, and molybdenum, with copper ≥0.5%, cobalt ≥0.1%, iron ≥4%, manganese ≥2%, zinc ≥5%, boron ≥2%, magnesium ≥2%, and molybdenum ≥0.1%, sourced from Jiangsu Caiwei Biotechnology Co., Ltd.; Bacillus spp. are sourced from the China Agricultural Microbial Culture Collection Center (ACCC64094); Lactobacillus plantarum is sourced from the China Industrial Microbial Culture Collection Center (CICC10481); Bacillus subtilis is sourced from the China Agricultural Microbial Culture Collection Center (ACCC60429); Bacillus vesiliflorus is sourced from the China Agricultural Microbial Culture Collection Center (ACCC64447); Bacillus licheniformis is sourced from the China Agricultural Microbial Culture Collection Center (ACCC60429). 03290; Bacillus megaterium was obtained from the China Agricultural Microbial Culture Collection Center, number ACCC 04307; Pediococcus pentosaceus was obtained from the China Agricultural Microbial Culture Collection Center, number ACCC 11119; Bacillus amyloliquefaciens was obtained from the China Agricultural Microbial Culture Collection Center, number ACCC 10167.

[0034] Example 1 (1) Preparation of plant-derived extracts Poplar bark was pulverized and passed through a 100-mesh sieve, then mixed with 70% ethanol at a ratio of 1:12 g / mL. The mixture was ultrasonically extracted at 55℃ and 35kHz for 30 min, filtered, and the filtrate was concentrated and dried to constant weight to obtain the ethanol extract. The residue was mixed with a eutectic solvent at a ratio of 1:25 g / mL, and extracted at 80℃ for 35 min. The mixture was filtered, and the filtrate was mixed with water at a volume ratio of 1:8. After adsorption with AB-8 macroporous adsorption resin, the mixture was eluted sequentially with 3Bv deionized water and 4Bv 75% ethanol solution. The ethanol eluent was collected, concentrated, dried to constant weight, and mixed with the ethanol extract to obtain the poplar bark extract. The eutectic solvent was prepared by mixing choline chloride and citric acid at a molar ratio of 1:1, heating and stirring at 75℃ and 250rpm for 30 min, adding water at 25% of the total mass of choline chloride and citric acid, and continuing stirring for 10 min to obtain the eutectic solvent. Moringa root was pulverized and passed through an 80-mesh sieve, then mixed with glucose and water at a mass ratio of 8:2:90. The mixture was sterilized to obtain a fermentation slurry, which was inoculated with a compound microorganism and anaerobic fermented at 30°C for 54 hours. The slurry was then sterilized, filtered, concentrated, and dried to constant weight to obtain the Moringa extract. The compound microorganism consisted of Bacillus and Lactobacillus plantarum at a viable count ratio of 3:2, with an inoculation amount of 6 × 10⁻⁶ cells / day. 7 CFU / mL fermentation slurry; Poplar bark extract and Moringa extract were mixed in a weight ratio of 1:1 to obtain plant-derived extracts.

[0035] (2) Preparation of stress-resistant and growth-promoting organic fertilizer Weigh the following raw materials by weight: 50 parts of decomposed organic matter (a mixture of decomposed cow manure and decomposed earthworm castings at a mass ratio of 3:1), 15 parts of biochar (rice husk char, particle size 0.5-2 mm), 5 parts of plant-derived extracts, 3 parts of oligosaccharides (a mixture of chitosan oligosaccharides and fucoidan oligosaccharides at a mass ratio of 8:3), 4 parts of minerals, 1.5 parts of microbial inoculant (composed of Bacillus subtilis and Bacillus belye, with Bacillus subtilis having a viable count of 1.2 billion CFU / g and Bacillus belye having a viable count of 1.7 billion CFU / g), and 2 parts of binder (a mixture of bentonite and sodium carboxymethyl cellulose at a mass ratio of 4:1). Well-rotted organic matter, biochar, and minerals are added to a vertical mixer and stirred at 200 r / min for 15 min to obtain a basic mixture. Oligosaccharides and plant-derived extracts are added in sequence and stirred for another 10 min. Then binders and microbial agents are added and stirred for another 15 min. Deionized water at 8% of the total mass of the materials is sprayed in, granulated, and dried to constant weight to obtain stress-resistant and growth-promoting organic fertilizer.

[0036] Example 2 (1) Preparation of plant-derived extracts Poplar bark was pulverized and passed through an 80-mesh sieve. It was then mixed with 65% ethanol at a ratio of 1:10 g / mL and extracted ultrasonically at 50℃ and 30kHz for 35 minutes. The mixture was filtered, concentrated, and dried to constant weight to obtain the ethanol extract. The residue was mixed with a eutectic solvent at a ratio of 1:20 g / mL and extracted at 75℃ for 40 minutes. The mixture was filtered, and the filtrate was mixed with water at a volume ratio of 1:6. After adsorption with AB-8 macroporous adsorption resin, the mixture was eluted sequentially with 2Bv deionized water and 3Bv 70% ethanol solution. The ethanol eluent was collected, concentrated, dried to constant weight, and mixed with the ethanol extract to obtain the poplar bark extract. The eutectic solvent was prepared by mixing choline chloride and citric acid at a molar ratio of 1:0.8 and heating and stirring at 72℃ and 200rpm for 35 minutes. Water (20% of the total mass of choline chloride and citric acid) was added, and stirring was continued for 12 minutes to obtain the eutectic solvent. Moringa root was pulverized and passed through a 60-mesh sieve, then mixed with glucose and water at a mass ratio of 7:1:80. The mixture was sterilized to obtain a fermentation slurry, which was then inoculated with a compound microorganism and anaerobic fermented at 28°C for 60 hours. The slurry was then sterilized, filtered, concentrated, and dried to constant weight to obtain the Moringa extract. The compound microorganism consisted of Bacillus and Lactobacillus plantarum at a viable count ratio of 2:1, with an inoculation amount of 4 × 10⁻⁶ cells / day. 7 CFU / mL fermentation slurry; Poplar bark extract and Moringa extract were mixed at a weight ratio of 1:0.8 to obtain plant-derived extracts.

[0037] (2) Preparation of stress-resistant and growth-promoting organic fertilizer Weigh the following raw materials by weight: 40 parts of decomposed organic matter (a mixture of decomposed straw and decomposed peat in a mass ratio of 1:1), 10 parts of biochar (bamboo charcoal, particle size 1-3 mm), 2 parts of plant-derived extract (prepared in step (1) of Example 2), 1 part of oligosaccharide (a mixture of chitosan oligosaccharide and brown algae oligosaccharide in a mass ratio of 5:2), 2 parts of minerals, 0.5 parts of microbial agent (composed of Bacillus subtilis and Bacillus belye, with Bacillus subtilis having a viable count of 1.5 billion / g and Bacillus belye having a viable count of 2 billion / g), and 1 part of binder (a mixture of bentonite and sodium carboxymethyl cellulose in a mass ratio of 3:0.8). Well-rotted organic matter, biochar, and minerals are put into a vertical mixer and stirred at 150 r / min for 20 min to obtain a basic mixture. Oligosaccharides and plant-derived extracts are added in sequence and stirred for another 8 min. Then binders and microbial agents are added and stirred for 12 min. 6% of the total mass of deionized water is sprayed in, granulated, and dried to constant weight to obtain stress-resistant and growth-promoting organic fertilizer.

[0038] Example 3 (1) Preparation of plant-derived extracts Poplar bark was pulverized and passed through a 120-mesh sieve, then mixed with 75% ethanol at a ratio of 1:15 g / mL. The mixture was ultrasonically extracted at 60℃ and 40kHz for 25 min, filtered, and the filtrate was concentrated and dried to constant weight to obtain the ethanol extract. The residue was mixed with a eutectic solvent at a ratio of 1:30 g / mL, and extracted at 85℃ for 30 min. The mixture was filtered, and the filtrate was mixed with water at a volume ratio of 1:10. After adsorption with AB-8 macroporous adsorption resin, the mixture was eluted sequentially with 4 Bv deionized water and 5 Bv 80% ethanol solution. The ethanol eluent was collected, concentrated, dried to constant weight, and mixed with the ethanol extract to obtain the poplar bark extract. The eutectic solvent was prepared by mixing choline chloride and citric acid at a molar ratio of 1:1.2, heating and stirring at 80℃ and 300 rpm for 25 min, adding water at 28% of the total mass of choline chloride and citric acid, and continuing stirring for 8 min to obtain the eutectic solvent. Moringa root was pulverized and passed through a 100-mesh sieve, then mixed with glucose and water at a mass ratio of 9:3:100. The mixture was sterilized to obtain a fermentation slurry, which was inoculated with a compound microbial culture and anaerobic fermented at 32℃ for 48 hours. The slurry was then sterilized, filtered, concentrated, and dried to constant weight to obtain the Moringa extract. The compound microbial culture consisted of Bacillus and Lactobacillus plantarum at a viable count ratio of 4:3, with an inoculation amount of 8 × 10⁻⁶ cells / day. 7 CFU / mL fermentation slurry; Poplar bark extract and Moringa extract were mixed at a weight ratio of 1:1.2 to obtain plant-derived extracts.

[0039] (2) Preparation of stress-resistant and growth-promoting organic fertilizer Weigh the following raw materials by weight: 60 parts of decomposed organic matter (a mixture of decomposed cow manure and decomposed peat in a mass ratio of 2:1), 20 parts of biochar (coconut shell charcoal, particle size 0.3-1mm), 8 parts of plant-derived extract, 5 parts of oligosaccharides (a mixture of chitosan oligosaccharides and fucoidan oligosaccharides in a mass ratio of 10:4), 6 parts of minerals, 3 parts of microbial inoculant (composed of Bacillus subtilis and Bacillus belye, with Bacillus subtilis having a viable count of 1 billion CFU / g and Bacillus belye having a viable count of 1.3 billion CFU / g), and 4 parts of binder (a mixture of bentonite and sodium carboxymethyl cellulose in a mass ratio of 5:2). Well-rotted organic matter, biochar, and minerals are added to a vertical mixer and stirred at 250 r / min for 12 min to obtain a basic mixture. Oligosaccharides and plant-derived extracts are added in sequence and stirred for another 12 min. Then binders and microbial agents are added and stirred for 18 min. Deionized water at 8% of the total mass of the material is sprayed in, granulated, and dried to constant weight to obtain stress-resistant and growth-promoting organic fertilizer.

[0040] Comparative Example 1 The only difference from Example 1 is that the plant-derived extract consists only of poplar bark extract (the amount is the same as the total amount of plant-derived extract in Example 1, i.e., 5 parts), without the addition of moringa extract. The remaining components and amounts are exactly the same as in Example 1, and the preparation method is the same as in Example 1.

[0041] Comparative Example 2 The only difference from Example 1 is that the plant-derived extract consists only of Moringa extract (the amount is the same as the total amount of plant-derived extract in Example 1, i.e., 5 parts), without the addition of poplar bark extract. The remaining components and amounts are exactly the same as in Example 1, and the preparation method is the same as in Example 1.

[0042] Comparative Example 3 The only difference from Example 1 is that the preparation method of poplar bark extract in the plant-derived extract is as follows: poplar bark is crushed and passed through a 100-mesh sieve, mixed with 70% ethanol at a material-to-liquid ratio of 1:12 g / mL, and ultrasonically extracted at a temperature of 55℃ and a frequency of 35kHz for 30 min. After filtration, the filtrate is concentrated and dried to constant weight to obtain poplar bark extract.

[0043] Comparative Example 4 The only difference from Example 1 is that the preparation method of the poplar bark extract in the plant-derived extract is as follows: poplar bark is crushed and passed through a 100-mesh sieve, mixed with a eutectic solvent at a material-to-liquid ratio of 1:25 g / mL, heated and extracted at 80°C for 35 min, filtered, and the filtrate is mixed with water at a volume ratio of 1:8. After adsorption by AB-8 type macroporous adsorption resin, it is eluted sequentially with 3Bv deionized water and 4Bv 75% ethanol solution. The ethanol eluent is collected, concentrated, and dried to constant weight to obtain the poplar bark extract. The preparation method of the eutectic solvent is as follows: choline chloride and citric acid are mixed at a molar ratio of 1:1, heated and stirred at 75°C and 250 rpm for 30 min, and water equal to 25% of the total mass of choline chloride and citric acid is added. Stirring is continued for 10 min to obtain the eutectic solvent.

[0044] Comparative Example 5 The only difference from Example 1 is that the preparation method of the Moringa extract in the plant-derived extract is as follows: Moringa root is crushed and passed through an 80-mesh sieve, mixed with glucose and water at a mass ratio of 8:2:90, sterilized, and fermented to obtain a fermentation slurry. A compound microorganism is inoculated, and the mixture is anaerobic fermented at 30°C for 54 hours. After sterilization and filtration, the filtrate is concentrated and dried to constant weight to obtain the Moringa extract. The compound microorganism consists of Bacillus licheniformis and Pediococcus pentosaceus at a viable count ratio of 3:2, with an inoculation amount of 6 × 10⁻⁶ cells / day. 7 CFU / mL fermentation slurry.

[0045] Comparative Example 6 The only difference from Example 1 is that the oligosaccharide is obtained by mixing fructooligosaccharide and soybean oligosaccharide in a weight ratio of 8:3.

[0046] Comparative Example 7 The only difference from Example 1 is that the microbial agent is composed of Bacillus megaterium and Bacillus amyloliquefaciens. In the microbial agent, the viable count of Bacillus megaterium is 1.2 billion / g, and the viable count of Bacillus amyloliquefaciens is 1.7 billion / g.

[0047] Experimental Example 1 The effects of stress-resistant and growth-promoting organic fertilizers in Examples 1-3 and Comparative Examples 1-7 on crop resistance were investigated.

[0048] (1) Germination rate Terracotta pots with an inner diameter of 25 cm and a height of 30 cm were selected as experimental containers, and 10 kg of saline-alkali test soil was added to each pot. The experimental group (Examples 1-3, control group, and comparative examples 1-7) was mixed with the soil at a rate of 0.5 kg / pot and left to stand for 7 days at a temperature of 25±2℃, a relative humidity of 65±2%, and a soil moisture content of 60±5%.

[0049] Set up a blank control group 1 (no fertilizer) and 10 experimental groups, with 5 replicates for each group.

[0050] Sow 30 sterilized cucumber seeds (Jin Chun No. 4) evenly in each pot at a depth of 1.5 cm. Germination rate was recorded on the 5th day after sowing, with germination defined as the radicle breaking through the seed coat by 1 mm. Germination rate (%) = (Number of germinated seeds ÷ Total number of seeds) × 100%. The specific results are shown in Table 1. The number of germinated seeds in Table 1 is the total number from 5 replicates.

[0051] Table 1. Effects of various stress-resistant and growth-promoting organic fertilizers on germination rate. Blank control group 1 52 34.7 Example 1 141 94.0 Example 2 135 90.0 Example 3 138 92.0 Comparative Example 1 116 77.3 Comparative Example 2 111 74.0 Comparative Example 3 107 71.3 Comparative Example 4 119 79.3 Comparative Example 5 104 69.3 Comparative Example 6 126 84.0 Comparative Example 7 120 80.0 As shown in Table 1, the germination rate of Examples 1-3 was significantly higher than that of the blank control group, indicating that the stress-resistant and growth-promoting organic fertilizer of the present invention can alleviate the inhibitory effect of salt and alkali on cucumbers. Specifically, the salicin precursor in the poplar bark extract is converted into salicylic acid through endogenous seed metabolism, activating acquired resistance, effectively improving salt stress, and protecting the integrity of the radicle meristem cell membrane. The active ingredients in the Moringa extract, after fermentation by specific microorganisms, can improve seed resistance, and its acidic components neutralize alkaline stress in the rhizosphere microzone. The combination of these two extracts significantly improved the germination rate compared to the single extracts (Comparative Examples 1-2), indicating that the combination has a synergistic resistance-inducing effect. Comparative Example 3 only used alcohol to extract poplar bark, and Comparative Example 4 only used eutectic solvent extraction; both had lower germination rates than Example 1, proving that only alcohol-water two-phase fractional extraction can fully obtain the stress-resistant active components and improve resistance to saline-alkali soil. Comparative Example 5, due to the use of a different microbial strain for fermenting Moringa, showed insufficient conversion of active metabolites and a lower germination rate, indicating the advantage of combined fermentation with *Bacillus* and *Lactobacillus plantarum* in releasing the germination-promoting activity of Moringa. Comparative Example 6, by changing the type of oligosaccharide, showed a lower germination rate and lower salt-alkali resistance than Example 1. Comparative Example 7, by changing the type of microbial agent, showed lower salt-alkali resistance than Example 1. This demonstrates that specific oligosaccharides and microbial agents have positive effects on improving saline-alkali soil.

[0052] (2) Effects on root resistance of cucumber seedlings Terracotta pots with an inner diameter of 25 cm and a height of 30 cm were selected as experimental containers, and 10 kg of saline-alkali test soil was added to each pot. The experimental group (Examples 1-3, control group, and comparative examples 1-7) was mixed with the soil at a rate of 0.5 kg / pot and left to stand for 7 days at a temperature of 25±2℃, a relative humidity of 65±2%, and a soil moisture content of 60±5%.

[0053] Two blank control groups (no fertilizer) and 10 experimental groups were set up, with 5 replicates for each group.

[0054] Two cucumber seedlings (Jinchun No. 4) with the same growth condition and two leaves and one heart were transplanted into terracotta cultivation pots at a rate of 3 seedlings / pot. The temperature was 25±2℃ during the day and 16±2℃ at night, with a light intensity of 10000±2000 lux for the first 3 days and 25000±2000 lux after 3 days) for 12 hours / day.

[0055] Fifteen days after transplanting, the soil around the seedling roots was rinsed off, the roots were cut off, and root activity, indoleacetic acid content, and biomass were measured and tested. The specific results are shown in Table 2.

[0056] The root vigor detection method is the triphenyltetrazole reduction method: Take 0.5g of fresh root tip, mix it with 5mL of 0.4% triphenyltetrazole solution and 5mL of phosphate buffer with pH 7, incubate at 37℃ in the dark for 1h, then add 2mL of 1mol / L sulfuric acid to terminate the reaction, extract the red product with ethyl acetate, measure the absorbance at a wavelength of 485nm, and calculate the reduction amount of triphenyltetrazole.

[0057] The indoleacetic acid (IAA) content was detected using an indoleacetic acid (IAA) content test kit (Shanghai Enzyme-Link Biotechnology Co., Ltd., catalog number ml077231).

[0058] The biomass detection method is as follows: the roots are blanched at 105℃ for 20 minutes, dried at 70℃ to constant weight, and the dry weight is measured.

[0059] Table 2. Effects of various stress-resistant and growth-promoting organic fertilizers on root resistance in cucumber seedlings. Blank control group 2 119.5 23.9 147.1 Example 1 192.1 45.7 227.4 Example 2 185.7 44.8 224.6 Example 3 188.0 45.3 226.3 Comparative Example 1 152.4 34.5 189.9 Comparative Example 2 148.3 33.2 185.2 Comparative Example 3 143.6 31.6 179.8 Comparative Example 4 155.9 35.0 191.7 Comparative Example 5 139.2 30.4 175.4 Comparative Example 6 168.0 38.3 203.0 Comparative Example 7 162.8 37.1 198.5 As shown in Table 2, the root activity, indoleacetic acid (IAA) content, and biomass of Examples 1-3 were all superior to those of the blank control group 2 and the comparative example used, indicating that the fertilizer of this invention can significantly improve the impact of saline-alkali soil on crops. The decomposed organic matter of this invention can improve the rhizosphere microenvironment, continuously supplying carbon and nitrogen nutrients to the roots and beneficial bacteria; the porous structure of biochar provides a colonization carrier for Bacillus subtilis and Bacillus belesiensis, ensuring the survival of the bacterial community in a high-salt environment and the secretion of growth-promoting metabolites, directly increasing the IAA content in the roots; the segmented dual extraction process for preparing poplar bark extract completely preserves the inducing substances, activates the crop's systemic resistance, and alleviates oxidative damage to cell membranes under salt stress; Moringa roots undergo anaerobic fermentation with Bacillus subtilis and Lactobacillus plantarum to stimulate root growth, and the combination of the two forms a synergistic root-promoting system. Combined with chitosan oligosaccharides and fucoidan oligosaccharides, it can be directly absorbed by the roots to enhance stress resistance and can also promote the targeted proliferation of beneficial rhizosphere bacteria. Comparative Examples 1 and 2 used only one type of plant-derived extract, lacking a synergistic effect, resulting in a significant decrease in root index values. Comparative Examples 3 and 4 had insufficient extraction of active ingredients, leading to reduced root vitality. Comparative Example 5 changed the Moringa fermentation strain, resulting in insufficient active metabolites. Comparative Example 6 changed the type of oligosaccharide, and Comparative Example 7 changed the functional Bacillus, reducing the rhizosphere growth-promoting ability, and decreasing root vitality, auxin content, and root dry weight. This indicates that the plant extract extraction process, specific oligosaccharides, and specific microbial agents in the fertilizer of this invention are all indispensable, working together to achieve robust root development under saline-alkali conditions.

[0060] Experimental Example 2 Daejeon Experiment Field trials were conducted to verify the effects of stress-resistant and growth-promoting organic fertilizers (Examples 1-3 and Comparative Examples 1-7) on soil improvement and cucumber yield in saline-alkali land.

[0061] Using Jinchun No. 4 cucumber as the test crop, the experiment was designed with 11 treatments, each with 5 replicates, for a total of 55 experimental plots, each plot with an area of ​​30 square meters. The plots were randomly arranged, and each plot had a protection row. There were no significant differences in soil (saline-alkali soil) conditions among the plots.

[0062] Experimental group: conventional fertilization + stress-resistant and growth-promoting organic fertilizer; CK: Conventional fertilization.

[0063] The experimental group and the control group had the same field management practices.

[0064] Conventional fertilization: Apply 50 kg of compound fertilizer (15-15-15), 50 kg of potassium sulfate, and 150 kg of organic fertilizer per mu, and water 3 times in total.

[0065] Basal application of slow-release microbial fertilizer: Apply the stress-resistant and growth-promoting organic fertilizer of Examples 1-3 / Comparative Examples 1-7 at a dosage of 100 kg / mu, and bury it in the soil layer at a depth of 7-10 cm.

[0066] pH, porosity, and total salt content were measured at the beginning and end of the harvesting period, and the average value of the results was taken.

[0067] The pH value is detected by probe-based direct measurement.

[0068] The porosity was measured using the ring cutter method.

[0069] The method for determining total salt content is NY / T 1121.16-2006 Soil Testing Part 16: Determination of Total Water-Soluble Salt Content in Soil by Conductivity Method.

[0070] After harvesting, all cucumbers in each plot were weighed, the average yield of a single plot was calculated, and the yield increase rate was calculated.

[0071] The specific results for pH value, porosity, total salt content, and yield for each group are shown in Table 3. Table 3. Results of pH value, porosity, total salt content, and yield for each group. initial 8.96 34.3 5.07 — CK 8.45 43.8 4.75 193.9 Example 1 7.72 59.5 3.12 212.6 Example 2 7.87 57.7 3.24 208.4 Example 3 7.81 58.9 3.19 210.1 Comparative Example 1 8.14 52.0 3.97 201.7 Comparative Example 2 8.17 51.4 4.01 198.5 Comparative Example 3 8.29 50.8 4.16 197.3 Comparative Example 4 8.03 53.6 3.88 202.5 Comparative Example 5 8.38 50.2 4.23 196.8 Comparative Example 6 7.90 55.5 3.57 205.0 Comparative Example 7 8.09 54.1 3.70 203.2 As shown in Table 3, the initial soil salinization was observed, with the control (CK) showing only slight improvement and a weak effect on salt and alkali reduction. The experimental results relied on biochar to chelate sodium and carbonate ions in the soil, and the decomposed organic matter to promote soil aggregate formation, increase soil porosity, and reduce soil compaction. Poplar bark and Moringa extracts, containing weakly acidic active ingredients, buffered the rhizosphere pH balance. Combined with oligosaccharides to regulate the reproduction of beneficial bacteria, and functional Bacillus continuously activated the micronutrients fixed by salt and alkali in the soil, these multiple pathways reduced soil pH and salinity. The comparative examples, due to the lack of compound plant extracts, simplified extraction processes, and replacement of bacterial strains or oligosaccharides, exhibited decreased soil buffering, ion chelation, and bacterial activation capabilities, resulting in lower porosity increases and less effective salt and alkali reduction compared to the experimental results.

[0072] Improving soil physicochemical properties alleviates saline-alkali growth stress, enhances cucumber root vitality and nutrient absorption capacity, and significantly increases yield. In the example plot, cucumber yields were far higher than the control (CK) and all comparative proportions. Any alteration to any key component reduced the soil remediation, root growth promotion, and crop yield increase effects to varying degrees, fully demonstrating the synergistic effect of the multiple components of this invention—composted organic matter, biochar, compound plant extracts, specific oligosaccharides, and functional microbial agents—which can simultaneously improve saline-alkali land remediation, induce crop stress resistance, and increase yield.

[0073] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A stress-resistant and growth-promoting organic fertilizer, characterized in that, The raw materials include the following parts by weight: 40-60 parts of decomposed organic matter, 10-20 parts of biochar, 2-8 parts of plant-derived extract, 1-5 parts of oligosaccharides, 2-6 parts of minerals, 0.5-3 parts of microbial inoculant, and 1-4 parts of binder. The plant-derived extract is composed of poplar bark extract and moringa extract in a weight ratio of 1:(0.8-1.2).

2. The stress-resistant and growth-promoting organic fertilizer according to claim 1, characterized in that, The decomposed organic matter is two or more of the following: decomposed cow dung, decomposed earthworm castings, decomposed straw, and decomposed peat.

3. The stress-resistant and growth-promoting organic fertilizer according to claim 1, characterized in that, The preparation method of the poplar bark extract includes: crushing poplar bark and mixing it with an ethanol solution, ultrasonically extracting, filtering, concentrating the filtrate, drying to obtain an ethanol extract, mixing the filter residue with a eutectic solvent, heating and extracting, filtering, mixing the filtrate with water, purifying it through a macroporous resin, drying, and mixing it with the ethanol extract to obtain the poplar bark extract; the preparation method of the eutectic solvent includes: mixing choline chloride and citric acid in a molar ratio of 1:(0.8-1.2), heating, and mixing with water to obtain the eutectic solvent.

4. The stress-resistant and growth-promoting organic fertilizer according to claim 3, characterized in that, The volume fraction of the ethanol solution is 65%-75%; the material-to-liquid ratio of the ultrasonic extraction is 1:(10-15)g / mL, the temperature is 50-60℃, the frequency is 30-40kHz, and the time is 25-35min.

5. The stress-resistant and growth-promoting organic fertilizer according to claim 3, characterized in that, The mass-to-volume ratio of the filter residue to the eutectic solvent is 1:(20-30)g / mL, and the extraction temperature is 75-85℃ for 30-40min.

6. The stress-resistant and growth-promoting organic fertilizer according to claim 1, characterized in that, The preparation method of the moringa extract includes: crushing moringa roots, mixing with glucose and water, sterilizing to obtain a fermentation slurry, inoculating with compound microorganisms for anaerobic fermentation, filtering, concentrating the filtrate, and drying to obtain the moringa extract.

7. The stress-resistant and growth-promoting organic fertilizer according to claim 6, characterized in that, The composite microorganisms consist of Bacillus and Lactobacillus plantarum in a viable count ratio of (2-4):(1-3); the inoculation amount of the composite microorganisms is (4-8)×10⁻⁶. 7 CFU / mL fermentation slurry; the fermentation temperature is 28-32℃ and the time is 48-60h.

8. The stress-resistant and growth-promoting organic fertilizer according to claim 1, characterized in that, The microbial agent is composed of Bacillus subtilis and Bacillus belye.

9. A method for preparing a stress-resistant and growth-promoting organic fertilizer according to any one of claims 1-8, characterized in that, The process includes: mixing well-rotted organic matter, biochar, and minerals to obtain a basic mixture, then sequentially mixing it with oligosaccharides, plant-derived extracts, binders, and microbial agents, granulating, and drying to obtain a stress-resistant and growth-promoting organic fertilizer.

10. The application of a stress-resistant and growth-promoting organic fertilizer according to any one of claims 1-8 in the preparation of fertilizers for improving saline-alkali soil and increasing yield.