CN115028496A

CN115028496A - Saline-alkali tolerant plant growth promoter and preparation method and application thereof

Info

Publication number: CN115028496A
Application number: CN202210970180.0A
Authority: CN
Inventors: 聂作常; 王效金; 陈永安; 李冰; 郭兆亮; 邹鹏
Original assignee: Weifang Yangguang Chemical Co ltd
Current assignee: Weifang Yangguang Chemical Co ltd
Priority date: 2022-08-12
Filing date: 2022-08-12
Publication date: 2022-09-09

Abstract

The invention provides a saline-alkali tolerant plant growth promoter and a preparation method and application thereof, belonging to the technical field of plant growth regulators. The saline-alkali tolerant plant growth promoter prepared by the invention is beneficial to improving the physical and chemical structure of saline-alkali soil, reducing the pH value and the conductivity of the soil, fixing heavy metal ions, promoting the rooting, germination and growth and development of plants, improving the stress resistance of the plants, playing a good role in promoting the growth of the plants, realizing the recycling of agricultural waste resources, reducing the non-point source pollution caused by agricultural production and having certain environmental benefit.

Description

Saline-alkali tolerant plant growth promoter and preparation method and application thereof

Technical Field

The invention relates to the technical field of plant growth regulators, in particular to a saline-alkali tolerant plant growth promoter and a preparation method and application thereof.

Background

The saline soil or alkaline earth is the soil in which the pH value of the soil is higher and crops are difficult to grow after the concentration of soluble salts or replaceable sodium ions in the soil reaches a certain degree. The problem of soil salinization widely exists in the world, and about 0.27 hundred million hectares of saline-alkali soil is mainly distributed in inland areas of northeast, north China and northwest China and coastal areas of the north of Yangtze river, wherein about 0.06 hundred million hectares of saline-alkali cultivated land and 0.21 hundred million hectares of saline-alkali wasteland exist in China. In addition, in arid and semiarid regions, due to continental climate, rare rainfall and strong evaporation, if irrigation measures are not proper, such as large fertilizer input, secondary salinization of soil is easy to occur.

Salinization causes deterioration of physical and chemical properties of soil, mainly manifested by increase of soil salinity and pH, relative decrease of soil organic matter content, deterioration of nutrient supply conditions, inhibition of soil microbial activities, difficulty in absorbing water and nutrients added into fertilizers by crop roots, physiological drought and nutrient deficiency, and inhibition of crop growth and development due to salt damage, thereby causing negative influence on plant growth, seedling shortage of crops (plants) planted in saline soil, reduction of plant growth, and even failure of production. In particular, the main damage of saline-alkali environment to plants is reflected in the following three aspects: firstly, the salt segregant in the saline-alkali soil can generate physiological toxicity, and because the plants absorb a large amount of sodium ions (Na) ⁺ ) Chloride ion (Cl) ^- ) Etc., thereby destroying the ion balance in plant cells and inhibiting the physiological and biochemical metabolic processes in the cells, resulting in the reduction of the photosynthesis capability of the plants; secondly, the increase of the soil salinity increases the concentration of the soil solution, and the osmotic pressure is continuously improved, so that the capacity of the plants for absorbing water from the soil is weakened, and physiological drought occurs; thirdly, the pH value of the saline-alkali soil is higher, so that the plants are unbalanced with the acid and alkali of the external environment.

Therefore, in order to effectively reduce the damage of the saline-alkali environment to the plants, on one hand, the saline-alkali stressed plants need to reduce the ion accumulation in the cytoplasm, and on the other hand, the saline-alkali stressed plants need to produce some special products, such as protein, amino acid, sugar, and the like, through the accumulation process to enhance the osmotic pressure of the cells, thereby preventing the cells from losing water and stabilizing the plasma membrane and the structure of enzymes.

The plant growth promoter is mainly used for promoting the health and the efficient growth of plants, mostly contains plant hormones artificially prepared or extracted from the plants, added fertilizers, trace elements and the like, and is widely applied to agriculture and forestry production. The growth and development of the plants can be accelerated by reasonably applying the plant growth promoter, and the growth quality of the plants is improved. In order to comprehensively meet different elements required by plant growth, the growth promoters used in large quantities at present generally consist of a plurality of nutritional and non-business components, more artificial synthesis or extracts are added, and the blending process is complex.

At present, substances such as plant hormones, trace elements, microbial fertilizers and the like are mainly used as common plant growth promoters, but the substances are expensive, so that the planting cost is high. The artificially synthesized growth promoter can be divided into auxin, gibberellin, cytokinin, brassinolide, polyamine, etc. The existing growth promoter only promotes the cell division of plants, breaks apical dominance and the like generally, mainly plays a role similar to hormone, and has poor fruit quality and poor plant absorption effect.

Chinese patent application CN101686667A discloses a plant growth promoter with high safety and no harm to human body, which contains ubiquinone as its main active ingredient, and although the plant growth promoter has high safety and low harm, the production process is complex, the cost is high, and in addition, the plant growth promoter has significant effect only in the initial stage of plant growth, and the defects of low product utilization rate and poor application effect often appear in the practical application process.

Chinese patent application CN103508761A discloses a plant growth promoter, the manufacturing process of which is mainly an improvement of the traditional biogas fermentation technology, and the process comprises the working procedures of anaerobic fermentation, oxygenation, inorganic ceramic membrane filtration, nanofiltration, reverse osmosis, evaporative concentration and the like. Although the manufacturing process is environment-friendly and ecological, the process is complex, the production cost is high, and especially the reverse osmosis and other steps have high requirements on process conditions, so that the manufacturing process is not suitable for large-scale production and application.

Disclosure of Invention

The invention aims to provide a saline-alkali tolerant plant growth promoter, a preparation method and application thereof, which are beneficial to improving the physical and chemical structure of saline-alkali soil, reducing the pH value and the conductivity of the soil, fixing heavy metal ions, promoting the rooting, the germination and the growth and development of plants, improving the stress resistance of the plants, playing a good role in promoting the growth of the plants, realizing the recycling of agricultural waste resources, reducing the non-point source pollution caused by agricultural production and having certain environmental benefits.

The technical scheme of the invention is realized as follows:

the invention provides a preparation method of a saline-alkali tolerant plant growth promoter, which is characterized in that nutrient solution containing carbon sources, nitrogen sources, trace elements, vitamins and amino acids and conditioner containing pyroligneous liquor, potassium fulvate, gibberellin, naphthylacetic acid and compound sodium nitrophenolate are enriched in porous hollow silica microspheres to obtain microspheres rich in nutrients and conditioner, and the microspheres are fixedly carried on bentonite soaked in an alkali solution together with a composite microbial inoculum prepared from Znobel, Serratia and Bacillus megaterium to prepare bentonite carrying the composite microbial inoculum and the microspheres; and (2) crushing the desulfurized gypsum and the rice hull to obtain a mixture, adding the mixture into calcium alginate gel, adding the prepared immobilized composite microbial inoculum and the microspherical bentonite, and uniformly stirring and mixing to obtain the saline-alkali tolerant plant growth promoter.

As a further improvement of the invention, the method comprises the following steps:

s1, preparing porous hollow silica microspheres: dropping aminosilane into a water solution containing a pore-foaming agent, stirring for reaction, centrifugally washing, and spray drying to obtain porous hollow silica microspheres;

s2, preparing nutrient solution: dissolving carbon source, nitrogen source, trace elements, vitamins and amino acid in water to prepare nutrient solution;

s3, preparing a conditioner: dissolving pyroligneous liquor, potassium fulvate, gibberellin, naphthylacetic acid and compound sodium nitrophenolate in water to prepare a conditioner;

s4, preparing microspheres rich in nutrients and a conditioner: dispersing the porous hollow silica microspheres prepared in the step S1 in the nutrient solution prepared in the step S2, adding the conditioner prepared in the step S3, stirring and mixing uniformly, concentrating, and freeze-drying to obtain microspheres rich in nutrients and conditioners;

s5, preparing a composite microbial inoculum: uniformly mixing the Zubeiella, the Serratia and the Bacillus megaterium to prepare a composite microbial inoculum;

s6, preparing bentonite immobilized with a composite microbial agent and microspheres: adding bentonite into a dilute alkali solution, stirring for reaction, filtering, washing to obtain modified bentonite, adding the prepared modified bentonite into water, adding the microspheres rich in nutrients and conditioning agents prepared in the step S4 and the composite microbial inoculum prepared in the step S5, uniformly dispersing, concentrating, and freeze-drying to obtain bentonite immobilized composite microbial inoculum and microspheres;

s7, preparation of the saline-alkali tolerant plant growth promoter: mixing and crushing desulfurized gypsum and rice hull, sieving to obtain a mixture, adding the mixture into a sodium alginate solution, dropwise adding a calcium ion solution, uniformly stirring to form a gel rich in the mixture, adding the immobilized composite microbial inoculum prepared in the step S6 and microspherical bentonite, uniformly stirring and mixing, and freeze-drying to obtain the saline-alkali tolerant plant growth promoter.

As a further improvement of the present invention, in step S1, the aminosilane is selected from at least one of γ -aminopropyltrimethoxysilane, γ -aminopropyltriethoxysilane, N- β (aminoethyl) - γ -aminopropyltrimethoxysilane, N- β (aminoethyl) - γ -aminopropyltriethoxysilane, N- β (aminoethyl) - γ -aminopropylmethyldimethoxysilane, N- β (aminoethyl) - γ -aminopropylmethyldiethoxysilane, and diethylenetriaminopropyltrimethoxysilane; the pore-foaming agent is selected from at least one of polyoxyethylene sorbitan fatty acid ester and polyethylene glycol octyl phenyl ether; the mass ratio of the aminosilane to the pore-foaming agent is 100: 2-5; the stirring reaction temperature is 60-80 ℃, and the reaction time is 5-7 h.

As a further improvement of the present invention, in step S2, the carbon source is at least one selected from molasses, glucose, fructose, soluble starch, maltose, isomaltose, sucrose, succinic acid, citric acid, lactic acid, acetic acid, methanol and ethanol; the nitrogen source is at least one selected from fish meal, silkworm chrysalis meal, peptone, bran, peanut cake meal, soybean cake meal, cottonseed cake meal, corn steep liquor, yeast powder, ammonium salt, nitrate and ammonia water; the ammonium salt is selected from at least one of ammonium chloride, ammonium nitrate and ammonium sulfate; the nitrate is selected from at least one of sodium nitrate, potassium nitrate, copper nitrate, aluminum nitrate and calcium nitrate; the trace elements are selected from at least one of sodium chloride, potassium chloride, sodium sulfate, potassium sulfate, calcium chloride, magnesium sulfate, ferric chloride, zinc sulfate, copper sulfate, manganese sulfate, zinc chloride, copper chloride and manganese chloride; the vitamins are selected from vitamin C, vitamin B1, vitamin B2, vitamin B6, folic acid, vitamin A, vitamin K, vitamin B12, vitamin D, and vitamin E; the amino acid is at least one of glycine, serine, threonine, valine, tryptophan, leucine, alanine, cysteine, methionine, lysine, isoleucine and phenylalanine; the mass ratio of the carbon source, the nitrogen source, the trace elements, the vitamins, the amino acids and the water is 10-20:5-12:0.5-1:1-2:3-7: 100; in the step S3, the mass ratio of the wood vinegar, the potassium fulvate, the gibberellin, the naphthylacetic acid, the compound sodium nitrophenolate to the water is 5-12: 5-10: 0.01-0.1:0.01-0.12:1-3:100.

As a further improvement of the invention, the mass ratio of the porous hollow silica microspheres, the nutrient solution and the conditioner in the step S4 is 10:15-30: 12-20; in the step S5, the mass ratio of the Zolbertlewisia, the Serratia and the Bacillus megaterium is 3-5:1-3: 5-7.

As a further improvement of the invention, in the step S6, the solid-to-liquid ratio of the bentonite to the dilute alkali solution is 1:3-5g/mL, and the stirring reaction time is 1-2 h; the dilute alkali solution is a NaOH solution or a KOH solution with the concentration of 5-10 wt%; the mass ratio of the modified bentonite to the microspheres rich in nutrients and conditioners to the composite microbial inoculum is 100:17-25: 7-12.

As a further improvement of the invention, the mass ratio of the desulfurized gypsum to the rice husk in the step S7 is 3-7: 5; the mesh number of the sieved screen is 100-150 meshes; the solid-liquid ratio of the mixture to the sodium alginate solution is 2-3:5 g/mL; the concentration of the sodium alginate in the sodium alginate solution is 35-40 wt%; the concentration of calcium ions in the calcium ion solution is 3-5 wt%; the mass ratio of the gel of the rich mixture to the bentonite of the immobilized composite microbial inoculum and the microspheres is 10: 5-7.

As a further improvement of the invention, the method specifically comprises the following steps:

s1, preparing porous hollow silica microspheres: dropping 100 parts by weight of aminosilane into 200 parts by weight of aqueous solution containing 2-5 parts by weight of pore-foaming agent, heating to 60-80 ℃, stirring and reacting for 5-7h, centrifugally washing, and spray drying to obtain porous hollow silica microspheres;

s2, preparation of nutrient solution: dissolving 10-20 parts by weight of carbon source, 5-12 parts by weight of nitrogen source, 0.5-1 part by weight of trace elements, 1-2 parts by weight of vitamins and 3-7 parts by weight of amino acid in 100 parts by weight of water, and uniformly stirring and mixing to prepare a nutrient solution;

s3, preparing a conditioner: dissolving 5-12 parts by weight of pyroligneous liquor, 5-10 parts by weight of potassium fulvate, 0.01-0.1 part by weight of gibberellin, 0.01-0.12 part by weight of naphthylacetic acid and 1-3 parts by weight of compound sodium nitrophenolate in 100 parts by weight of water, and stirring and mixing uniformly to prepare a conditioner;

s4, preparing the microspheres rich in nutrients and conditioners: dispersing 10 parts by weight of the porous hollow silica microspheres prepared in the step S1 in 15-30 parts by weight of the nutrient solution prepared in the step S2, adding 12-20 parts by weight of the conditioner prepared in the step S3, uniformly stirring and mixing, concentrating, and freeze-drying to obtain microspheres rich in nutrients and conditioners;

s5, preparing a composite microbial inoculum: uniformly mixing 3-5 parts by weight of Zoebelia, 1-3 parts by weight of Serratia and 5-7 parts by weight of Bacillus megaterium to prepare a composite microbial agent;

s6, preparing bentonite immobilized with a composite microbial agent and microspheres: adding bentonite into 5-10wt% NaOH solution or KOH solution, wherein the solid-to-liquid ratio of the bentonite to the NaOH solution or the KOH solution is 1:3-5g/mL, stirring for reaction for 1-2h, filtering, washing to obtain modified bentonite, adding 100 parts by weight of the prepared modified bentonite into water, adding 17-25 parts by weight of microspheres rich in nutrients and conditioning agents prepared in the step S4 and 7-12 parts by weight of the composite microbial inoculum prepared in the step S5, uniformly dispersing, concentrating, and freeze-drying to obtain bentonite immobilized composite microbial inoculum and microspheres;

s7, preparation of the saline-alkali tolerant plant growth promoter: mixing and crushing 3-7 parts by weight of desulfurized gypsum and 5 parts by weight of rice hull, sieving the mixture with a sieve of 100-150 meshes to obtain a mixture, adding the mixture into 35-40wt% of sodium alginate solution, wherein the solid-to-liquid ratio of the mixture to the sodium alginate solution is 2-3:5g/mL, dropwise adding calcium ion solution with the calcium ion concentration of 3-5wt%, uniformly stirring to form a gel rich in the mixture, adding 5-7 parts by weight of the immobilized composite microbial inoculum prepared in the step S6 and microsphere bentonite into 10 parts by weight of the gel rich in the mixture, uniformly stirring and mixing, and freeze-drying to obtain the saline-alkali resistant plant growth promoter.

The invention further protects the saline-alkali tolerant plant growth promoter prepared by the preparation method.

The invention further protects the application of the saline-alkali tolerant plant growth promoter in promoting the growth of plants in saline-alkali soil.

The invention has the following beneficial effects: in the preparation process of the porous hollow silica microsphere, aminosilane cannot be dissolved in water, the aminosilane is dripped into water, the aminosilane is dispersed into tiny liquid drops in the continuous stirring process, meanwhile, as the reaction proceeds, the amino is protonated to form an amphiphilic molecular structure to stabilize silane liquid drops, meanwhile, an alkaline environment is provided to catalyze the aminosilane to perform a sol-gel reaction, the aminosilane is continuously consumed at the interface of the liquid drops, so that the hollow microsphere is obtained, and meanwhile, a pore-forming agent in the water forms a pore channel at the microsphere interface, so that the porous hollow silica microsphere is formed;

gibberellin, naphthylacetic acid, compound sodium nitrophenolate and the like are plant growth promoters, gibberellin can accelerate germination and enable leaves of seedlings to be lengthened, seed peeling is promoted, the rate of emergence is improved, naphthylacetic acid can promote division of plant cells and growth of germs, compound sodium nitrophenolate can improve the germination capacity of plants, seedling growth is promoted, root system rooting growth is promoted, and therefore growth and development of the plants are promoted; the wood vinegar and the potassium fulvate have strong solubility, can improve the physical and chemical properties of soil, reduce the pH value of the soil, increase the content of aggregate in the soil, improve the structure of the soil, improve the yield and the stress resistance of crops, reduce the content of salt in the soil, increase the content of organic matters, improve the activity parameter of the soil enzyme, improve the properties of the soil, and the prepared conditioner has the effects of improving the soil performance of saline-alkali soil, reducing the pH value of the soil and promoting the growth and development of plants;

the nutrient solution is rich in nutrient elements required by the growth of microorganisms, is mixed with a conditioner, enters the microspheres from pore passages by a concentration loading method, is fixed inside the porous hollow silica microspheres, is frozen and dried, so that a large amount of nutrient substances and conditioners are enriched in the hollow pores of the microspheres, and meanwhile, the microspheres can well form hydrogen bonds with modified bentonite with a large amount of hydroxyl groups on the surface after the surface is subjected to alkali treatment so as to be fixed, so that the microspheres rich in the nutrient and conditioner can be fixed on the modified bentonite, on the other hand, the modified bentonite with a large amount of hydroxyl groups on the surface is easy to load a large amount of composite microbial agents comprising beyerba, serratia and bacillus megaterium due to the large specific surface area of the modified bentonite, and the microorganisms propagate in a large amount by utilizing the nutrient substances in the microspheres rich in the nutrient and conditioner so as to promote the growth of plant roots, the nitrogen element and the phosphorus element are enriched, and the required nutrients are provided for the growth of plants, so that the growth of the plants is promoted;

the Zubeiella has the functions of fixing nitrogen, producing siderophores, producing indoleacetic acid and ACC deaminase, the Serratia and the Bacillus megaterium have the functions of fixing nitrogen, dissolving phosphorus, producing indoleacetic acid and ACC deaminase, the three bactericides can well resist saline and alkaline land, and the three bactericides cooperate to synthesize phytohormone according to amino acid generated by seeds so as to promote seed germination, root growth and development, improve stress resistance of plants, accelerate growth speed and play a good role in promoting plant growth;

in addition, desulfurized gypsum is low in harmful heavy metal content and is used as a calcareous modifier by virtue of Ca contained therein ²⁺ Replacement of Na in saline-alkali soil colloid ⁺ The method has the advantages that salt leaching is promoted, the soil exchangeable sodium percentage and the sodium ion adsorption ratio are reduced, the saline-alkali soil is improved, the rice hulls are loose in texture and good in air permeability, the water retention capacity of the soil can be enhanced, meanwhile, the rice hulls contain rich carbon sources, the soil nutrient content can be increased when the rice hulls are applied to the soil, effective absorption of plants to quick-acting nutrient elements is promoted, the application amount of fertilizers is reduced, recycling of agricultural waste resources is realized, and agricultural production is reducedThe formed non-point source pollution is characterized in that the mixture obtained by mixing and crushing the desulfurized gypsum and the rice hull is fixed in calcium alginate gel, on one hand, the high molecular structure of the mixture can absorb and keep a large amount of water, the water retention capacity of soil is enhanced, the soil structure is stabilized, and meanwhile, the mixture can be effectively mixed with the bentonite immobilized with the composite microbial agent and the microspheres and added into the soil, so that the soil microbial community and the soil physical and chemical structure are improved, heavy metal ions are fixed, and the pollution of heavy metals to plants is reduced.

The bentonite is subjected to alkali treatment, has a large number of hydroxyl structures on the surface, has extremely high specific surface area, is easy to enrich microbial agents, and is in hydrogen bond connection with microspheres of a nutrient and conditioner, so that the microbes are mixed with the microspheres of the nutrient and conditioner, nutrient substances in the microspheres flow out to promote the growth of the microbes, and the bentonite has a loose structural characteristic and has a good promoting effect on absorbing and maintaining a large amount of water, enhancing the water retention capacity of soil and stabilizing the soil structure;

the saline-alkali tolerant plant growth promoter prepared by the invention is beneficial to improving the physical and chemical structure of saline-alkali soil, reducing the pH value and the conductivity of the soil, fixing heavy metal ions, promoting the rooting, germination and growth and development of plants, improving the stress resistance of the plants, playing a good role in promoting the growth of the plants, realizing the recycling of agricultural waste resources, reducing the non-point source pollution caused by agricultural production and having certain environmental benefit.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a TEM image of porous hollow silica microspheres obtained in example 1 of the present invention;

FIG. 2 is an SEM image of the enriched and conditioner microspheres obtained in example 1 of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Beyerba, english name: zobellella taiwanensis, cat # XG-J7125; supplied by Shanghai West Biotech, Inc.; the Serratia is Serratia prli and is provided by Shanghai-one-research biotechnology limited company; bacillus megaterium, cat # WH320, was supplied by North Noro Biotech, Inc., Shanghai.

The fulvic acid potassium is provided by Henan Yinhai chemical industry Co., Ltd, and the fulvic acid content is 55%; the wood vinegar is provided by Shandong mountain Tian chemical engineering and technology Limited, and the content of effective components is more than 99 percent; the compound sodium nitrophenolate is provided by Wuhanpeng Bio-technology Limited; the sodium alginate is provided by Anhui Xinchangteng food Co., Ltd, and the content of effective substances is more than 98%; the desulfurized gypsum is provided by Shanghai Honghang novel building materials Co.Ltd; the rice hulls are rice hulls of rice provided by a Hunan Quyuan farm; the bentonite has 325 meshes, is white, has a pH value of 5-7 and an expansion multiple of 20-60, and is provided by mineral processing factories in Fengyue of Lingshu county.

In each step of the examples and comparative examples of the present invention, the parts by weight are different unit amounts, which do not interfere with each other, and it is determined in each step according to the actual situation how much the unit amount of the parts by weight is.

Example 1

The embodiment provides a preparation method of a saline-alkali tolerant plant growth promoter, which specifically comprises the following steps:

s1, preparing porous hollow silica microspheres: dropping 100 parts by weight of gamma-aminopropyltrimethoxysilane into 200 parts by weight of aqueous solution containing 2 parts by weight of polyethylene glycol octyl phenyl ether, heating to 60 ℃, stirring and reacting for 5 hours, centrifuging at 3000r/min for 15 minutes, washing with clear water, and spray drying to obtain porous hollow silica microspheres; FIG. 1 is a TEM image of the prepared porous hollow silica microspheres, from which it can be seen that the prepared microspheres have a hollow structure;

s2, preparing nutrient solution: dissolving 5 parts by weight of glucose, 5 parts by weight of fructose, 4 parts by weight of fish meal, 1 part by weight of ammonium nitrate, 0.2 part by weight of sodium chloride, 0.1 part by weight of calcium chloride, 0.1 part by weight of magnesium sulfate, 0.1 part by weight of ferric chloride, 0.5 part by weight of vitamin C, 0.3 part by weight of vitamin B12, 0.2 part by weight of vitamin D, 1 part by weight of threonine, 1 part by weight of valine and 1 part by weight of tryptophan in 100 parts by weight of water, stirring and mixing for 15min at a speed of 300r/min to prepare a nutrient solution;

s3, preparing a conditioner: dissolving 5 parts by weight of pyroligneous liquor, 5 parts by weight of potassium fulvate, 0.01 part by weight of gibberellin, 0.01 part by weight of naphthylacetic acid and 1 part by weight of compound sodium nitrophenolate in 100 parts by weight of water, and uniformly stirring and mixing to prepare a conditioner;

s4, preparing the microspheres rich in nutrients and conditioners: adding 10 parts by weight of the porous hollow silica microspheres prepared in the step S1 into 15 parts by weight of the nutrient solution prepared in the step S2, ultrasonically dispersing for 20min at 1000W, adding 12 parts by weight of the conditioner prepared in the step S3, stirring and mixing for 15min at 300r/min, concentrating, and freeze-drying to obtain microspheres rich in nutrients and the conditioner; fig. 2 is an SEM image of the prepared nutrient and conditioner enriched microsphere, and it can be seen that the microsphere has a large number of pores on the surface to facilitate the entry of nutrient solution and conditioner and the later release in soil.

S5, preparing a composite microbial inoculum: uniformly mixing 3 parts by weight of Zoebelia, 1 part by weight of Serratia and 5 parts by weight of Bacillus megaterium to prepare a composite microbial inoculum;

s6, preparing bentonite immobilized with a composite microbial agent and microspheres: adding bentonite into 5wt% NaOH solution, wherein the solid-to-liquid ratio of the bentonite to the NaOH solution is 1:3g/mL, stirring and reacting for 1h, filtering and washing to obtain modified bentonite, adding 100 parts by weight of the prepared modified bentonite into 200 parts by weight of water, adding 17 parts by weight of the microspheres rich in nutrients and conditioning agents prepared in the step S4 and 7 parts by weight of the composite microbial inoculum prepared in the step S5, performing 1000W ultrasonic dispersion for 30min, concentrating, and freeze-drying to obtain bentonite immobilized with the composite microbial inoculum and the microspheres;

s7, preparation of the saline-alkali tolerant plant growth promoter: mixing and crushing 3 parts by weight of desulfurized gypsum and 5 parts by weight of rice hull, sieving with a 100-mesh sieve to obtain a mixture, adding the mixture into a 35wt% sodium alginate solution, wherein the solid-to-liquid ratio of the mixture to the sodium alginate solution is 2:5g/mL, dropwise adding a calcium chloride solution with the calcium ion concentration of 3wt%, stirring at 300r/min for 15min to form a gel rich in the mixture, adding 5 parts by weight of the immobilized composite microbial agent prepared in the step S6 and microsphere bentonite into 10 parts by weight of the gel rich in the mixture, stirring at 300r/min for 20min, and freeze-drying to obtain the saline-alkali resistant plant growth promoter.

Example 2

s1, preparing porous hollow silica microspheres: dripping 100 parts by weight of N-beta (aminoethyl) -gamma-aminopropylmethyldimethoxysilane into 200 parts by weight of aqueous solution containing 5 parts by weight of polyoxyethylene sorbitan fatty acid ester, heating to 80 ℃, stirring for reaction for 7 hours, centrifuging at 3000r/min for 15 minutes, washing with clear water, and spray drying to obtain porous hollow silica microspheres;

s2, preparation of nutrient solution: dissolving 10 parts by weight of fructose, 8 parts by weight of sucrose, 2 parts by weight of succinic acid, 5 parts by weight of corn steep liquor, 5 parts by weight of yeast powder, 2 parts by weight of ammonium nitrate, 0.5 part by weight of sodium chloride, 0.2 part by weight of manganese sulfate, 0.1 part by weight of zinc chloride, 0.2 part by weight of copper chloride, 1 part by weight of vitamin C, 0.5 part by weight of vitamin B1, 0.5 part by weight of vitamin B2, 2 parts by weight of methionine, 2 parts by weight of lysine, 2 parts by weight of isoleucine and 1 part by weight of phenylalanine in 100 parts by weight of water, stirring and mixing for 15min at 300r/min to prepare a nutrient solution;

s3, preparing a conditioner: dissolving 12 parts by weight of pyroligneous liquor, 10 parts by weight of potassium fulvate, 0.1 part by weight of gibberellin, 0.12 part by weight of naphthylacetic acid and 3 parts by weight of compound sodium nitrophenolate in 100 parts by weight of water, and uniformly stirring and mixing to prepare a conditioner;

s4, preparing microspheres rich in nutrients and a conditioner: adding 10 parts by weight of the porous hollow silica microspheres prepared in the step S1 into 30 parts by weight of the nutrient solution prepared in the step S2, ultrasonically dispersing for 20min at 1000W, adding 20 parts by weight of the conditioner prepared in the step S3, stirring and mixing for 15min at 300r/min, concentrating, and freeze-drying to obtain microspheres rich in nutrients and the conditioner;

s5, preparing a composite microbial inoculum: uniformly mixing 5 parts by weight of Zoebelia, 3 parts by weight of Serratia and 7 parts by weight of Bacillus megaterium to prepare a composite microbial inoculum;

s6, preparing bentonite immobilized with a composite microbial agent and microspheres: adding bentonite into 10wt% KOH solution, wherein the solid-to-liquid ratio of the bentonite to the KOH solution is 1:5g/mL, stirring for reaction for 2 hours, filtering and washing to obtain modified bentonite, adding 100 parts by weight of the prepared modified bentonite into 200 parts by weight of water, adding 25 parts by weight of the microspheres rich in nutrients and conditioning agents prepared in the step S4 and 12 parts by weight of the composite microbial inoculum prepared in the step S5, performing 1000W ultrasonic dispersion for 30 minutes, concentrating, and freeze-drying to obtain bentonite immobilized with the composite microbial inoculum and the microspheres;

s7, preparation of the saline-alkali tolerant plant growth promoter: mixing and crushing 7 parts by weight of desulfurized gypsum and 5 parts by weight of rice hull, sieving the mixture with a 150-mesh sieve to obtain a mixture, adding the mixture into a 40wt% sodium alginate solution, wherein the solid-to-liquid ratio of the mixture to the sodium alginate solution is 3:5g/mL, dropwise adding a calcium chloride solution with the calcium ion concentration of 5wt%, stirring the mixture at 300r/min for 15min to form a gel rich in the mixture, adding 7 parts by weight of the immobilized composite microbial agent prepared in the step S6 and the microspherical bentonite into 10 parts by weight of the gel rich in the mixture, stirring the mixture at 300r/min for 20min, and freeze-drying to obtain the saline-alkali resistant plant growth promoter.

Example 3

s1, preparing porous hollow silica microspheres: dropping 100 parts by weight of diethylenetriaminopropyltrimethoxysilane into 200 parts by weight of aqueous solution containing 3.5 parts by weight of polyoxyethylene sorbitan fatty acid ester, heating to 70 ℃, stirring for reaction for 6 hours, centrifuging at 3000r/min for 15 minutes, washing with clear water, and spray-drying to obtain porous hollow silica microspheres;

s2, preparation of nutrient solution: dissolving 5 parts by weight of maltose, 4 parts by weight of isomaltose, 2 parts by weight of citric acid, 1 part by weight of ethanol, 5 parts by weight of peanut cake powder, 4 parts by weight of yeast powder, 1 part by weight of ammonium chloride, 0.2 part by weight of sodium chloride, 0.15 part by weight of calcium chloride, 0.15 part by weight of magnesium sulfate, 0.1 part by weight of zinc chloride, 0.1 part by weight of copper chloride, 0.1 part by weight of manganese chloride, 1 part by weight of vitamin C, 0.2 part by weight of vitamin D, 0.2 part by weight of vitamin E, 0.1 part by weight of folic acid, 2 parts by weight of methionine, 2 parts by weight of lysine and 1 part by weight of isoleucine in 100 parts by weight of water, and stirring and mixing for 15min at 300r/min to prepare a nutrient solution;

s3, preparing a conditioner: dissolving 9 parts by weight of pyroligneous, 7 parts by weight of potassium fulvate, 0.05 part by weight of gibberellin, 0.07 part by weight of naphthylacetic acid and 2 parts by weight of compound sodium nitrophenolate in 100 parts by weight of water, and uniformly stirring and mixing to prepare a conditioner;

s4, preparing the microspheres rich in nutrients and conditioners: adding 10 parts by weight of the porous hollow silica microspheres prepared in the step S1 into 22 parts by weight of the nutrient solution prepared in the step S2, ultrasonically dispersing for 20min at 1000W, adding 17 parts by weight of the conditioner prepared in the step S3, stirring and mixing for 15min at 300r/min, concentrating, and freeze-drying to obtain microspheres rich in nutrients and the conditioner;

s5, preparing a composite microbial inoculum: uniformly mixing 4 parts by weight of Zoebelia, 2 parts by weight of Serratia and 6 parts by weight of Bacillus megaterium to prepare a composite microbial inoculum;

s6, preparing bentonite immobilized with a composite microbial agent and microspheres: adding bentonite into a 7wt% NaOH solution, wherein the solid-liquid ratio of the bentonite to the NaOH solution is 1:4g/mL, stirring and reacting for 1.5h, filtering and washing to obtain modified bentonite, adding 100 parts by weight of the prepared modified bentonite into 200 parts by weight of water, adding 22 parts by weight of microspheres rich in nutrients and conditioners prepared in the step S4 and 10 parts by weight of composite microbial inoculum prepared in the step S5, performing 1000W ultrasonic dispersion for 30min, concentrating, and freeze-drying to obtain bentonite immobilized composite microbial inoculum and microspheres;

s7, preparation of the saline-alkali tolerant plant growth promoter: mixing and crushing 5 parts by weight of desulfurized gypsum and 5 parts by weight of rice hull, sieving the mixture with a 150-mesh sieve to obtain a mixture, adding the mixture into a 37wt% sodium alginate solution, wherein the solid-to-liquid ratio of the mixture to the sodium alginate solution is 2.5:5g/mL, dropwise adding a calcium chloride solution with the calcium ion concentration of 4wt%, stirring the mixture at 300r/min for 15min to form a mixture-rich gel, adding 6 parts by weight of the immobilized composite microbial agent and microsphere bentonite prepared in the step S6 into 10 parts by weight of the mixture-rich gel, stirring the mixture at 300r/min for 20min, and freeze-drying to prepare the saline-alkali resistant plant growth promoter.

Comparative example 1

In comparison with example 3, no pyroligneous acid was added in step S3.

The method comprises the following specific steps:

s3, preparing a conditioner: dissolving 16 parts by weight of potassium fulvate, 0.05 part by weight of gibberellin, 0.07 part by weight of naphthylacetic acid and 2 parts by weight of compound sodium nitrophenolate in 100 parts by weight of water, and stirring and mixing uniformly to prepare the conditioner.

Comparative example 2

In comparison with example 3, no potassium fulvate was added in step S3.

The method comprises the following specific steps:

s3, preparing a conditioner: dissolving 16 parts by weight of pyroligneous liquor, 0.05 part by weight of gibberellin, 0.07 part by weight of naphthylacetic acid and 2 parts by weight of compound sodium nitrophenolate in 100 parts by weight of water, stirring and mixing uniformly to prepare the conditioner.

Comparative example 3

Compared to example 3, no gibberellin was added.

The method comprises the following specific steps:

s3, preparing a conditioner: dissolving 9 parts by weight of pyroligneous, 7 parts by weight of potassium fulvate, 0.12 part by weight of naphthylacetic acid and 2 parts by weight of compound sodium nitrophenolate in 100 parts by weight of water, and uniformly stirring and mixing to prepare the conditioner.

Comparative example 4

Compared to example 3, no naphthylacetic acid was added.

The method comprises the following specific steps:

s3, preparing a conditioner: dissolving 9 parts by weight of pyroligneous, 7 parts by weight of potassium fulvate, 0.12 part by weight of gibberellin and 2 parts by weight of compound sodium nitrophenolate in 100 parts by weight of water, and uniformly stirring and mixing to prepare the conditioner.

Comparative example 5

Compared to example 3, nutrient solution was not added in the preparation of the nutrient and conditioner rich microspheres.

The method specifically comprises the following steps:

s2, preparing a conditioner: dissolving 9 parts by weight of pyroligneous, 7 parts by weight of potassium fulvate, 0.05 part by weight of gibberellin, 0.07 part by weight of naphthylacetic acid and 2 parts by weight of compound sodium nitrophenolate in 100 parts by weight of water, and uniformly stirring and mixing to prepare a conditioner;

s3, preparing the conditioner-rich microspheres: adding 10 parts by weight of the porous hollow silica microspheres prepared in the step S1 into 39 parts by weight of the conditioner prepared in the step S2, performing ultrasonic dispersion at 1000W for 20min, concentrating, and performing freeze drying to obtain conditioner-rich microspheres;

s4, preparing a composite microbial inoculum: uniformly mixing 4 parts by weight of Zoebelia, 2 parts by weight of Serratia and 6 parts by weight of Bacillus megaterium to prepare a composite microbial inoculum;

s5, preparing bentonite immobilized with a composite microbial agent and microspheres: adding bentonite into 7wt% NaOH solution, wherein the solid-to-liquid ratio of the bentonite to the NaOH solution is 1:4g/mL, stirring and reacting for 1.5h, filtering and washing to obtain modified bentonite, adding 100 parts by weight of the prepared modified bentonite into 200 parts by weight of water, adding 22 parts by weight of the conditioner-rich microspheres prepared in the step S3 and 10 parts by weight of the composite microbial inoculum prepared in the step S4, performing 1000W ultrasonic dispersion for 30min, concentrating, and freeze-drying to obtain bentonite immobilized composite microbial inoculum and microspheres;

s6, preparing a saline-alkali tolerant plant growth promoter: mixing and crushing 5 parts by weight of desulfurized gypsum and 5 parts by weight of rice hull, sieving the mixture with a 150-mesh sieve to obtain a mixture, adding the mixture into a 37wt% sodium alginate solution, wherein the solid-to-liquid ratio of the mixture to the sodium alginate solution is 2.5:5g/mL, dropwise adding a calcium chloride solution with the calcium ion concentration of 4wt%, stirring the mixture at 300r/min for 15min to form a mixture-rich gel, adding 6 parts by weight of the immobilized composite microbial agent and microsphere bentonite prepared in the step S5 into 10 parts by weight of the mixture-rich gel, stirring the mixture at 300r/min for 20min, and freeze-drying to prepare the saline-alkali resistant plant growth promoter.

Comparative example 6

In contrast to example 3, the enriched and conditioner microspheres were prepared without added conditioner.

The method specifically comprises the following steps:

s1, preparing porous hollow silica microspheres: dropping 100 parts by weight of diethylenetriaminopropyltrimethoxysilane into 200 parts by weight of aqueous solution containing 3.5 parts by weight of polyoxyethylene sorbitan fatty acid ester, heating to 70 ℃, stirring and reacting for 6 hours, centrifuging at 3000r/min for 15 minutes, washing with clear water, and spray-drying to obtain porous hollow silica microspheres;

s2, preparing nutrient solution: dissolving 5 parts by weight of maltose, 4 parts by weight of isomaltose, 2 parts by weight of citric acid, 1 part by weight of ethanol, 5 parts by weight of peanut cake powder, 4 parts by weight of yeast powder, 1 part by weight of ammonium chloride, 0.2 part by weight of sodium chloride, 0.15 part by weight of calcium chloride, 0.15 part by weight of magnesium sulfate, 0.1 part by weight of zinc chloride, 0.1 part by weight of copper chloride, 0.1 part by weight of manganese chloride, 1 part by weight of vitamin C, 0.2 part by weight of vitamin D, 0.2 part by weight of vitamin E, 0.1 part by weight of folic acid, 2 parts by weight of methionine, 2 parts by weight of lysine and 1 part by weight of isoleucine in 100 parts by weight of water, and stirring and mixing for 15min at 300r/min to prepare a nutrient solution;

s3, preparing the nutrient-rich microspheres: adding 10 parts by weight of the porous hollow silica microspheres prepared in the step S1 into 39 parts by weight of the nutrient solution prepared in the step S2, performing ultrasonic dispersion at 1000W for 20min, concentrating, and freeze-drying to obtain nutrient-rich microspheres;

s5, preparing bentonite immobilized with a composite microbial agent and microspheres: adding bentonite into 7wt% NaOH solution, wherein the solid-to-liquid ratio of the bentonite to the NaOH solution is 1:4g/mL, stirring and reacting for 1.5h, filtering and washing to obtain modified bentonite, adding 100 parts by weight of the prepared modified bentonite into 200 parts by weight of water, adding 22 parts by weight of the nutrient-rich microspheres prepared in the step S3 and 10 parts by weight of the composite microbial inoculum prepared in the step S4, performing 1000W ultrasonic dispersion for 30min, concentrating, and freeze-drying to obtain bentonite immobilized composite microbial inoculum and microspheres;

Comparative example 7

Compared with the embodiment 3, the preparation of the bentonite immobilized with the composite microbial inoculum and the microspheres does not add the microspheres rich in nutrients and conditioners.

The method specifically comprises the following steps:

s1, preparing a composite microbial inoculum: uniformly mixing 4 parts by weight of Zoebelia, 2 parts by weight of Serratia and 6 parts by weight of Bacillus megaterium to prepare a composite microbial inoculum;

s2, preparing bentonite immobilized with the composite microbial inoculum: adding bentonite into 7wt% NaOH solution, wherein the solid-to-liquid ratio of the bentonite to the NaOH solution is 1:4g/mL, stirring and reacting for 1.5h, filtering and washing to obtain modified bentonite, adding 100 parts by weight of the prepared modified bentonite into 200 parts by weight of water, adding 32 parts by weight of the composite microbial inoculum obtained in the step S1, performing 1000W ultrasonic dispersion for 30min, concentrating, and freeze-drying to obtain bentonite immobilized with the composite microbial inoculum;

s3, preparing a saline-alkali tolerant plant growth promoter: mixing and crushing 5 parts by weight of desulfurized gypsum and 5 parts by weight of rice hull, sieving the mixture with a 150-mesh sieve to obtain a mixture, adding the mixture into a 37wt% sodium alginate solution, wherein the solid-to-liquid ratio of the mixture to the sodium alginate solution is 2.5:5g/mL, dropwise adding a calcium chloride solution with the calcium ion concentration of 4wt%, stirring the mixture at 300r/min for 15min to form a mixture-rich gel, adding 6 parts by weight of the bentonite of the immobilized composite microbial agent prepared in the step S2 into 10 parts by weight of the mixture-rich gel, stirring the mixture at 300r/min for 20min, and freeze-drying to obtain the saline-alkali resistant plant growth promoter.

Comparative example 8

Compared with the example 3, the saline-alkali tolerant plant growth promoter is prepared without adding desulfurized gypsum.

The method comprises the following specific steps:

s7, preparation of the saline-alkali tolerant plant growth promoter: crushing 10 parts by weight of rice hull, sieving the rice hull with a 150-mesh sieve to obtain a mixture, adding the mixture into a 37wt% sodium alginate solution, wherein the solid-to-liquid ratio of the mixture to the sodium alginate solution is 2.5:5g/mL, dropwise adding a calcium chloride solution with the calcium ion concentration of 4wt%, stirring the mixture at 300r/min for 15min to form a mixture-rich gel, adding 6 parts by weight of the immobilized composite microbial inoculum prepared in the step S6 and microsphere bentonite into the mixture-rich gel at 10 parts by weight, stirring the mixture at 300r/min for 20min, and freeze-drying to obtain the saline-alkali resistant plant growth promoter.

Comparative example 9

Compared with the example 3, the saline-alkali tolerant plant growth promoter is prepared without adding rice hulls.

The method comprises the following specific steps:

s7, preparation of the saline-alkali tolerant plant growth promoter: crushing 10 parts by weight of desulfurized gypsum, sieving the crushed desulfurized gypsum by a sieve of 150 meshes to obtain a mixture, adding the mixture into a 37wt% sodium alginate solution, wherein the solid-to-liquid ratio of the mixture to the sodium alginate solution is 2.5:5g/mL, dropwise adding a calcium chloride solution with the calcium ion concentration of 4wt%, stirring the mixture at 300r/min for 15min to form a gel rich in the mixture, adding 6 parts by weight of the immobilized composite microbial agent prepared in the step S6 and the microspherical bentonite into the 10 parts by weight of the gel rich in the mixture, stirring the mixture at 300r/min for 20min, and freeze-drying the mixture to obtain the saline-alkali resistant plant growth promoter.

Comparative example 10

Compared with the embodiment 3, the bentonite is not used for immobilizing the complex microbial inoculum and the microspheres.

The method specifically comprises the following steps:

s2, preparation of nutrient solution: dissolving 5 parts by weight of maltose, 4 parts by weight of isomaltose, 2 parts by weight of citric acid, 1 part by weight of ethanol, 5 parts by weight of peanut cake powder, 4 parts by weight of yeast powder, 1 part by weight of ammonium chloride, 0.2 part by weight of sodium chloride, 0.15 part by weight of calcium chloride, 0.15 part by weight of magnesium sulfate, 0.1 part by weight of zinc chloride, 0.1 part by weight of copper chloride, 0.1 part by weight of manganese chloride, 1 part by weight of vitamin C, 0.2 part by weight of vitamin D, 0.2 part by weight of vitamin E, 0.1 part by weight of folic acid, 2 parts by weight of methionine, 2 parts by weight of lysine and 1 part by weight of isoleucine in 100 parts by weight of water, and stirring and mixing for 15min at a speed of 300r/min to prepare a nutrient solution;

s6, preparing a saline-alkali tolerant plant growth promoter: mixing and crushing 5 parts by weight of desulfurized gypsum and 5 parts by weight of rice hull, sieving the mixture with a 150-mesh sieve to obtain a mixture, adding the mixture into a 37wt% sodium alginate solution, wherein the solid-to-liquid ratio of the mixture to the sodium alginate solution is 2.5:5g/mL, dropwise adding a calcium chloride solution with the calcium ion concentration of 4wt%, stirring the mixture at 300r/min for 15min to form a gel rich in the mixture, adding 1 part by weight of the microspheres rich in nutrients and conditioning agents prepared in the step S4 and 0.5 part by weight of the composite microbial inoculum prepared in the step S5 into 10 parts by weight of the gel rich in the mixture, stirring the mixture at 300r/min for 20min, and freeze-drying to obtain the saline-alkali resistant plant growth promoter.

Comparative example 11

Compared with the embodiment 3, the preparation of the composite microbial inoculum is not added with the Zolbert.

The method comprises the following specific steps:

s5, preparing a composite microbial inoculum: uniformly mixing 2 parts by weight of serratia and 10 parts by weight of bacillus megaterium to prepare a composite microbial inoculum;

comparative example 12

Compared with the embodiment 3, the preparation of the composite microbial inoculum is not added with bacillus megaterium.

The method comprises the following specific steps:

s5, preparing a composite microbial inoculum: uniformly mixing 10 parts by weight of Zoebelia and 2 parts by weight of Serratia to prepare a composite microbial inoculum;

test example 1

The change of the physicochemical properties of the saline-alkali soil after the treatment of the saline-alkali tolerant plant growth promoter prepared in the examples 1 to 3 and the comparative examples 1 to 12.

The basic physicochemical properties of saline-alkali soil are shown in table 1.

TABLE 1

8kg of saline-alkali soil is filled in plastic basins and divided into an example 1-3 group, a comparative example 1-12 group and a blank group, wherein the example 1-3 group and the comparative example 1-12 group are applied with 100g of corresponding saline-alkali resistant plant growth promoter every week, the blank group is applied with the same amount of saline-alkali soil, each basin is irrigated with 300mL of clear water every week, the culture period of the uniformly mixed soil is 3 months, and sampling is carried out by a five-point method by using a sampler. The collected soil sample is naturally dried, ground and sieved by a 100-mesh sieve for measuring various indexes of soil, phosphatase adopts a disodium phenylphosphate colorimetric method, urease adopts a sodium phenolate-sodium hypochlorite colorimetric method, dehydrogenase adopts a TTC spectrophotometry method for measuring, and total microbial quantity adopts chloroform fumigation-K ₂ SO ₄ An extraction-carbon automatic analysis method, and a soil pH value determination method adopts a 1:5 soil-water mass ratio electrode method. The results are shown in Table 2.

Specific method references:

guanguanyin, soil enzyme and its research method, Beijing, agricultural Press, 1986.

TABLE 2

As can be seen from the above table, the saline-alkali tolerant plant growth promoter prepared in the embodiments 1 to 3 of the present invention can well improve the soil fertility of saline-alkali soil.

Test example 2

The saline-alkali soil is used for planting wheat, and the growth conditions of various groups of wheat are detected after the saline-alkali tolerant plant growth promoters prepared in examples 1-3 and comparative examples 1-12 are applied for treatment.

The wheat variety is India Triticum BDME-10, the wheat is planted in pots with the capacity of 1L by using a potting method, 8 wheat plants are planted in each pot, each group is repeated for 4 times, and the wheat variety is provided with an example 1-3 group, a comparative example 1-12 group, a blank group and an indoleacetic acid group. The saline-alkali tolerant plant growth promoter prepared in the examples 1-3 and the comparative examples 1-12 and water are prepared into a solution according to the mass ratio of 1:1000 for fertilization, indoleacetic acid is prepared into a 1ppm aqueous solution, the solution is poured for 1 time every day, 200mL of the solution is added every time, and a blank group is applied with the same amount of clear water. The test temperature is 25 +/-2 ℃ and the humidity is 45 +/-5%. After fertilizing for 1 month, performing statistics on the biomass of the overground part and the underground part of the wheat by a gravimetric method, measuring the tillering number by a numerical method, and analyzing the phosphorus content and the rhizosphere phosphatase activity in the plant by a U-3300 Toshiba ultraviolet spectrometer.

The results are shown in Table 3.

TABLE 3

As can be seen from the above table, the saline-alkali tolerant plant growth promoter prepared in the embodiments 1 to 3 of the present invention has an obvious effect of promoting the growth of wheat in saline-alkali soil.

Compared with the example 3, the comparative examples 1 and 2 have the advantages that wood vinegar or potassium fulvate is not added in the step S3, the pH value of soil is obviously improved, the activity of soil enzymes is reduced, the dry weight of root systems and stems and leaves of wheat is reduced, and the tillering number is reduced. The wood vinegar and the potassium fulvate have strong solubility, can improve the physical and chemical properties of soil, reduce the pH value of the soil, increase the content of soil aggregates and improve the soil structure, and can also improve the crop yield and the stress resistance, reduce the content of soil salt, increase the content of organic matters, improve the activity parameter of soil enzyme and improve the soil property.

Compared with the example 3, the comparative examples 3 and 4 have the advantages that gibberellin or naphthylacetic acid is not added, the dry weights of the root system and the stem leaf of the wheat are obviously reduced, the tillering number is obviously reduced, and the phosphorus contents of the root system and the stem leaf of the wheat are reduced. Gibberellin, naphthylacetic acid, compound sodium nitrophenolate and the like are plant growth promoters, the gibberellin can accelerate germination, leaves of seedlings can be lengthened, seed peeling is promoted, the emergence rate is improved, the naphthylacetic acid can promote cell division of the plants and growth of germs, the compound sodium nitrophenolate can improve germination capacity of the plants, growth of the seedlings and root growth of roots are promoted, and therefore growth and development of the plants are promoted.

Compared with the embodiment 3, the nutrient solution which is not added in the preparation of the microspheres rich in nutrients and conditioners reduces the content of soil microorganisms, the enzyme activity and the promotion effect on the growth of wheat. Compared with the embodiment 3, the conditioner is not added in the preparation of the microsphere rich in nutrients and conditioners, the pH value of soil is increased, the activity of soil enzymes is reduced, and the promotion effect on the growth of wheat is obviously reduced. Compared with the embodiment 3, the bentonite immobilized with the composite microbial inoculum and the microspheres does not contain the microspheres rich in nutrients and conditioners in preparation, so that the pH value of soil is obviously improved, the activity of soil enzymes is obviously reduced, the content of soil microorganisms is obviously reduced, and the promotion effect on the growth of wheat is obviously reduced. The nutrient solution is rich in nutrient elements required by the growth of microorganisms, is mixed with a conditioner, enters the microspheres from pore passages through a concentration loading method, is fixed inside the porous hollow silica microspheres, is frozen and dried, so that a large amount of nutrient substances and conditioners are enriched in the hollow pores of the microspheres, meanwhile, the microspheres can well form hydrogen bonds with modified bentonite with a large amount of hydroxyl groups on the surface after the surface is subjected to alkali treatment so as to be fixed on the modified bentonite, and on the other hand, the modified bentonite with a large amount of hydroxyl groups on the surface is easy to load a large amount of compound microbial agents comprising beyerba, serratia and bacillus megaterium due to the large specific surface area of the modified bentonite, and the microorganisms propagate in a large amount by utilizing the nutrient substances in the microspheres rich in the nutrient and conditioners to promote the growth of plant roots and enrich nitrogen and phosphorus elements so as to provide required nutrients for the growth of plants, thereby promoting plant growth;

compared with the example 3, the saline-alkali tolerant plant growth promoter has the advantages that no desulfurized gypsum or rice hulls are added in the preparation of the saline-alkali tolerant plant growth promoter, the pH value of soil is increased, the content of soil microorganisms is reduced, the dry weight of root systems and stem leaves of wheat is obviously reduced, and the tillering number is obviously reduced. The desulfurized gypsum is low in harmful heavy metal content, and can be used as a calcium modifier by virtue of Ca contained therein ²⁺ Replacement of Na in saline-alkali soil colloid ⁺ The method has the advantages that the salt leaching is promoted, the soil exchangeable sodium percentage and the sodium ion adsorption ratio are reduced, the saline-alkali soil is improved, the rice hulls are loose in texture and good in air permeability, the water retention capacity of the soil can be enhanced, meanwhile, the rice hulls contain rich carbon sources, the soil nutrient content can be increased when the rice hulls are applied to the soil, the effective absorption of plants to quick-acting nutrient elements is promoted, the application amount of fertilizers is reduced, the recycling of agricultural waste resources is realized, the area source pollution caused by agricultural production is reduced, the mixture obtained by mixing and crushing the desulfurized gypsum and the rice hulls is fixed in calcium alginate gel, on one hand, the polymer structure can absorb and maintain a large amount of water, the water retention capacity of the soil is enhanced, the soil structure is stabilized, meanwhile, the mixture, the bentonite of the immobilized microbial inoculum and the microspheres can be effectively mixed and added into the soil, the soil microbial community and the soil physical and chemical structure are improved, the heavy metal ions are fixed, and the pollution of heavy metals to plants is reduced.

Compared with the embodiment 3, the bentonite immobilized complex microbial inoculum and the microspheres are not passed, the pH value of the soil is increased, and the content of the soil microorganisms is reduced in the comparative example 10. The bentonite is subjected to alkali treatment, the surface of the bentonite is provided with a large number of hydroxyl structures, the bentonite has a very high specific surface area and is easy to enrich a microbial agent, and meanwhile, the bentonite is connected with microspheres of a nutrient and conditioner through hydrogen bonds, so that the microbes are mixed with the microspheres of the nutrient and conditioner, the flowing of nutrient substances in the microspheres promotes the growth of the microbes, and the loose structural characteristics of the bentonite have good promoting effects on absorbing and maintaining a large amount of water, enhancing the water retention capacity of soil and stabilizing the soil structure.

Compared with the embodiment 3, the preparation method of the composite microbial inoculum has the advantages that the Zubel bacterium or the Bacillus megaterium is not added in the preparation of the composite microbial inoculum, the activity of the soil enzyme is reduced, and the promotion effect on the growth of wheat is reduced. The Zubeiella has the functions of fixing nitrogen, producing siderophores and producing indoleacetic acid and ACC deaminase, the Serratia and the Bacillus megaterium have the functions of fixing nitrogen, dissolving phosphorus, producing indoleacetic acid and ACC deaminase, the three bactericides can well resist saline-alkali soil, and the three bactericides are synergistic, can synthesize phytohormone according to amino acid generated by seeds, so that the seed germination is promoted, the root system growth and development are realized, the stress resistance of plants is improved, the growth speed is accelerated, and the good effect of promoting the plant growth can be achieved.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. A preparation method of a saline-alkali tolerant plant growth promoter is characterized in that nutrient solution containing carbon sources, nitrogen sources, trace elements, vitamins and amino acids and conditioner containing pyroligneous acid, fulvic acid potassium, gibberellin, naphthylacetic acid and compound sodium nitrophenolate are enriched in porous hollow silica microspheres to obtain microspheres rich in nutrients and conditioner, and the microspheres are fixedly carried on bentonite soaked in an alkali solution together with a composite microbial inoculum prepared from Zlebella, Serratia and Bacillus megaterium to prepare bentonite carrying the composite microbial inoculum and the microspheres; and (2) crushing the desulfurized gypsum and the rice hull to obtain a mixture, adding the mixture into calcium alginate gel, adding the prepared immobilized composite microbial inoculum and the microspherical bentonite, and uniformly stirring and mixing to obtain the saline-alkali tolerant plant growth promoter.

2. The method of claim 1, comprising the steps of:

s2, preparation of nutrient solution: dissolving carbon source, nitrogen source, trace elements, vitamins and amino acid in water to prepare nutrient solution;

s4, preparing the microspheres rich in nutrients and conditioners: dispersing the porous hollow silica microspheres prepared in the step S1 in the nutrient solution prepared in the step S2, adding the conditioner prepared in the step S3, stirring and mixing uniformly, concentrating, and freeze-drying to obtain microspheres rich in nutrients and conditioners;

3. The method according to claim 2, wherein the aminosilane in step S1 is at least one selected from the group consisting of γ -aminopropyltrimethoxysilane, γ -aminopropyltriethoxysilane, N- β (aminoethyl) - γ -aminopropyltrimethoxysilane, N- β (aminoethyl) - γ -aminopropyltriethoxysilane, N- β (aminoethyl) - γ -aminopropylmethyldimethoxysilane, N- β (aminoethyl) - γ -aminopropylmethyldiethoxysilane, and divinyltriaminopropyltrimethoxysilane; the pore-foaming agent is selected from at least one of polyoxyethylene sorbitan fatty acid ester and polyethylene glycol octyl phenyl ether; the mass ratio of the aminosilane to the pore-foaming agent is 100: 2-5; the stirring reaction temperature is 60-80 ℃, and the reaction time is 5-7 h.

4. The method according to claim 2, wherein the carbon source in step S2 is at least one selected from molasses, glucose, fructose, soluble starch, maltose, isomaltose, sucrose, succinic acid, citric acid, lactic acid, acetic acid, methanol, and ethanol; the nitrogen source is at least one selected from fish meal, silkworm chrysalis meal, peptone, bran, peanut cake meal, soybean cake meal, cottonseed cake meal, corn steep liquor, yeast powder, ammonium salt, nitrate and ammonia water; the ammonium salt is selected from at least one of ammonium chloride, ammonium nitrate and ammonium sulfate; the nitrate is selected from at least one of sodium nitrate, potassium nitrate, copper nitrate, aluminum nitrate and calcium nitrate; the trace elements are selected from at least one of sodium chloride, potassium chloride, sodium sulfate, potassium sulfate, calcium chloride, magnesium sulfate, ferric chloride, zinc sulfate, copper sulfate, manganese sulfate, zinc chloride, copper chloride and manganese chloride; the vitamins are selected from vitamin C, vitamin B1, vitamin B2, vitamin B6, folic acid, vitamin A, vitamin K, vitamin B12, vitamin D and vitamin E; the amino acid is at least one of glycine, serine, threonine, valine, tryptophan, leucine, alanine, cysteine, methionine, lysine, isoleucine and phenylalanine; the mass ratio of the carbon source, the nitrogen source, the trace elements, the vitamins, the amino acids and the water is 10-20:5-12:0.5-1:1-2:3-7: 100; in the step S3, the mass ratio of the wood vinegar liquid, the potassium fulvate, the gibberellin, the naphthylacetic acid, the compound sodium nitrophenolate to the water is 5-12: 5-10: 0.01-0.1:0.01-0.12:1-3:100.

5. The preparation method according to claim 2, wherein the mass ratio of the porous hollow silica microspheres, the nutrient solution and the conditioner in step S4 is 10:15-30: 12-20; in the step S5, the mass ratio of the Zolbertlewisia, the Serratia and the Bacillus megaterium is 3-5:1-3: 5-7.

6. The preparation method of claim 2, wherein the solid-to-liquid ratio of the bentonite and the dilute alkali solution in step S6 is 1:3-5g/mL, and the stirring reaction time is 1-2 h; the dilute alkali solution is a NaOH solution or a KOH solution with the concentration of 5-10 wt%; the mass ratio of the modified bentonite to the microspheres rich in nutrients and conditioners to the composite microbial inoculum is 100:17-25: 7-12.

7. The preparation method according to claim 2, wherein the mass ratio of the desulfurized gypsum to the rice hulls in the step S7 is 3-7: 5; the mesh number of the sieved screen is 100-150 meshes; the solid-liquid ratio of the mixture to the sodium alginate solution is 2-3:5 g/mL; the concentration of the sodium alginate in the sodium alginate solution is 35-40 wt%; the concentration of calcium ions in the calcium ion solution is 3-5 wt%; the mass ratio of the gel of the rich mixture to the bentonite of the immobilized composite microbial inoculum and the microspheres is 10: 5-7.

8. The preparation method according to claim 2, characterized by comprising the following steps:

s6, preparing bentonite immobilized with a composite microbial agent and microspheres: adding bentonite into 5-10wt% NaOH solution or KOH solution, wherein the solid-to-liquid ratio of the bentonite to dilute alkali solution is 1:3-5g/mL, stirring for reaction for 1-2h, filtering, washing to obtain modified bentonite, adding 100 parts by weight of the prepared modified bentonite into water, adding 17-25 parts by weight of microspheres rich in nutrients and conditioning agents prepared in the step S4 and 7-12 parts by weight of composite microbial agents prepared in the step S5, uniformly dispersing, concentrating, and freeze-drying to obtain bentonite immobilized with the composite microbial agents and the microspheres;

9. A saline-alkali tolerant plant growth promoter produced by the process according to any one of claims 1 to 8.

10. Use of the saline-alkali tolerant plant growth promoter of claim 9 to promote plant growth in saline-alkali soil.