阅读说明：本技术 促进豆科种子在盐碱地萌发成苗的种衣剂及其制备方法 (Seed coating agent for promoting leguminous seeds to germinate into seedlings in saline-alkali soil and preparation method thereof ) 是由 陈泽霖 陈彬 张敏 胡萍 许勇 于 2021-08-30 设计创作，主要内容包括：本发明公开了一种促进豆科种子在盐碱地萌发成苗的种衣剂及其制备方法,其中种衣剂主要包括大豆根瘤菌液；芽孢杆菌a液；芽孢杆菌b液、丝素蛋白和蛋白胨等；通过在播种前包裹在种子外部形成薄膜,不仅在土壤外帮助种子抵抗非生物胁迫,在幼苗生长时,可在根际周围形成保护层,进一步减轻非生物胁迫对幼苗的危害,从而使得豆科种子健康生长。(The invention discloses a seed coating agent for promoting leguminous seeds to germinate and sprout in saline-alkali soil and a preparation method thereof, wherein the seed coating agent mainly comprises a soybean rhizobium liquid; liquid of bacillus a; bacillus liquid b, silk fibroin, peptone and the like; the film is formed by wrapping the seeds outside before sowing, so that the seeds are helped to resist abiotic stress outside soil, and a protective layer can be formed around the rhizosphere when seedlings grow, so that the harm of the abiotic stress to the seedlings is further reduced, and the leguminous seeds can grow healthily.)

1. A seed coating agent for promoting leguminous seeds to germinate into seedlings in saline-alkali soil is characterized by comprising a soybean rhizobium liquid, a bacillus a liquid, a bacillus b liquid, silk fibroin, trehalose and nutrient substances, wherein the silk fibroin and the trehalose form a film attached to the surface of the leguminous seeds, the nutrient substances and the soybean rhizobium liquid, the bacillus a liquid and the bacillus b liquid are wrapped inside the film, the nutrient substances provide amino acids and small molecular carbon sources necessary for the growth of the soybean rhizobium and the bacillus, lipopeptide antibiotics generated by the metabolism of the bacillus prevent the invasion of pathogenic bacteria, a protective layer is formed around the seeds, and the germination of the seeds is promoted.

2. The seed coating agent for promoting germination and seedling formation of leguminous seeds in saline-alkali soil according to claim 1, which specifically comprises the following components in parts by mass:

soybean rhizobium liquid: 200-300 parts;

bacillus liquid a: 170-240 parts;

bacillus liquid b: 130-180 parts;

silk fibroin: 50-80 parts;

peptone: 30-50 parts;

soybean lecithin: 8-12 parts;

trehalose: 100-150 parts;

chitosan oligosaccharide: 0.8-1.2 parts;

proline: 0.05-0.15 part;

gamma-aminobutyric acid: 0.1 to 0.5 portion

Purified water: 150 and 200 portions.

3. The seed coating agent for promoting germination and seedling formation of leguminous seeds in saline-alkali soil according to claim 1, wherein the rhizobium japonicum liquid is one or more selected from rhizobium japonicum, rhizobium meliloti and rhizobium leguminosarum, and the viable count is not less than 20X10⁸cfu/mL。

4. The seed coating agent for promoting germination and seedling formation of seeds of leguminous plants in saline-alkali soil according to claim 1, wherein the bacillus a liquid is one or more of bacillus licheniformis and bacillus subtilis, and the viable count is not less than 20X10⁸cfu/mL; the bacillus liquid b is one or more of bacillus megaterium and bacillus sphaericus, and the viable count is more than or equal to 20X10⁸cfu/mL。

5. The seed coating agent for promoting germination and seedling formation of leguminous seeds in saline-alkali soil according to claim 1, wherein the silk fibroin is a film-forming agent with molecular weight of 600-5500 Da; wherein the part of 2000-5000Da accounts for 70-80%, and the mesh number is 100-200; the content is more than or equal to 99 percent, and the water content is less than or equal to 5 percent.

6. The seed coating agent for promoting germination and seedling formation of seeds of leguminous plants in saline-alkali soil as claimed in claim 1, wherein the chitosan oligosaccharide is enzymolysis chitosan oligosaccharide from shrimp and crab shells, the molecular weight is 2000-5000Da, wherein the part of 1700-2500Da accounts for 75-85%, the mesh number is 100-200 meshes, the content is not less than 99%, and the water content is not more than 5%.

7. The seed coating agent for promoting leguminous seeds to germinate into seedlings in saline-alkali soil according to claim 1, wherein the proline is powdered proline with purity of not less than 99%; the gamma-aminobutyric acid is a gamma-aminobutyric acid solution with the purity of 450 g/L.

8. A preparation method of a seed coating agent for promoting leguminous seeds to germinate and sprout in saline-alkali soil is applied to the production of the seed coating agent for promoting leguminous seeds to germinate and sprout in saline-alkali soil as claimed in any one of claims 1 to 7, and the preparation method comprises the following steps:

s1, mixing the soybean rhizobium liquid, the bacillus a liquid and the bacillus b liquid according to a ratio, and stirring to obtain a solution A;

s2, weighing a certain mass of purified water, sequentially adding silk fibroin, peptone and soybean lecithin, stirring for 30min at a rotation speed of 150-;

and S3, mixing the solution A and the solution B according to the proportion, and stirring to obtain the seed coating agent.

9. The method for preparing the seed coating agent for promoting the germination and seedling formation of the leguminous seeds in the saline-alkali soil as claimed in claim 8, wherein in step S1, the rhizobium japonicum liquid, the bacillus a liquid and the bacillus b liquid are mixed according to the ratio of 5:4:3, and are stirred for 2-3 minutes at the rotation speed of 150-.

10. The method for preparing a seed coating agent for promoting germination and seedling establishment of leguminous seeds in saline-alkali soil according to claim 7, wherein in step S3, the solution A and the solution B are mixed according to a ratio of 7:3, and are stirred for 20-30 minutes at a rotation speed of 150-.

Technical Field

The invention relates to the technical field of seed coating agents, in particular to a seed coating agent for promoting leguminous seeds to germinate into seedlings in saline-alkali soil and a preparation method thereof.

Background

Population growth, soil degradation and pesticide abuse are major challenges that agriculture must face in the next decades, as this involves global food production. The seed enhancement technology will play a key role in supporting food safety by germinating the seeds in a degraded environment, reducing the germination time of the seeds and increasing the crop yield. To date, great efforts have been made to design plants that can adapt to different environments and germinate in the presence of abiotic stress sources (e.g., soil salinity, high temperatures and drought).

The area of the global saline-alkali soil is about 9.5 hundred million hectares, and the land occupies about 10 percent of the total land area of the global land. Soil salt can cause adverse effects on the growth and development of plants through osmotic stress or ion poisoning effects, and can cause ion imbalance in soil, so that the plants cannot utilize certain nutrients, the growth and development are inhibited, the crop yield is greatly reduced, and the development of agriculture is seriously hindered.

Researches show that root nodules of leguminous plants often have a nitrogen fixation effect and are excellent green manure and crops; the soybean is used as an oil crop with the largest planting area in China, meanwhile, China is the first major imports of soybean in the world, and planting of soybean in saline-alkali soil is a major problem which cannot be ignored at present, so that improvement of salt tolerance and quality of crops through a certain method is particularly important. The cultivated soybeans belong to moderate salt-tolerant plants, and the excessive salt in the soil can seriously inhibit the growth and development of the soybeans, so that the yield and the quality are reduced; moreover, soybeans have different salt tolerance in different growth stages, and the stage of the soybean with the weakest salt tolerance is the period of emergence and seedling formation. In this period, once the management is not good, the phenomena of non-emergence or dead seedlings are easy to occur, so that the seedlings are short and the ridges are broken. Therefore, the one-time sowing of the whole seedlings and the strong seedlings are the basis and key links for realizing the high yield, high quality and high efficiency of the soybeans in the saline-alkali soil.

The patent number CN201210435042.9 discloses a rape biological seed coating agent and a preparation method and application thereof, wherein the technology of the biological seed coating agent is applied to rape seeds, and related fertilizers are provided for providing nutrition for the growth and development of plants; publication No. CN1537425A discloses a rape pelleted coating drought-resistant seed coating agent and a preparation method thereof, which comprises the steps of respectively crushing 0.5-5% of water-retaining agent, 1-10% of talcum powder and 50-80% of white clay into powder with the fineness of more than 200 meshes; 0.15 to 0.40 percent of insecticide, 0.35 to 0.65 percent of bactericide, 0.05 to 0.15 percent of KHPO, 5 to 40 percent of peat and 240.01 to 0.03 percent of rooting powder are uniformly mixed and crushed into powder with the fineness of more than 250 meshes, the two patents are both used for obtaining seed coating agents, but pesticides or fertilizers are added, the policies of green agriculture advocated by the state are not met, the state advocates to reduce the application of pesticides, hormones and inorganic fertilizers to the environment, in addition, the seed coating agents are applied to conventional land and are used as seed coating agents for rape, and therefore, the seed coating agents are not applicable to soybeans growing in saline-alkali soil at all.

Disclosure of Invention

Aiming at the defects in the technology, the invention provides the seed coating agent for promoting the leguminous seeds to germinate into seedlings in the saline-alkali soil and the preparation method thereof.

In order to achieve the purpose, the invention provides a seed coating agent for promoting leguminous seeds to germinate and sprout in saline-alkali soil, which comprises a soybean rhizobium liquid, a bacillus a liquid, a bacillus b liquid, silk fibroin, trehalose and nutrients, wherein the silk fibroin and the trehalose form a film attached to the surface of the leguminous seeds, the nutrients, the soybean rhizobium liquid, the bacillus a liquid and the bacillus b liquid are wrapped inside the film, the nutrients provide amino acid and a small molecular carbon source necessary for the growth of the soybean rhizobium and the bacillus, and the lipopeptide antibiotics generated by the metabolism of the bacillus prevent the invasion of pathogenic bacteria, form a protective layer around the seeds and promote the germination of the seeds.

Preferably, the feed additive specifically comprises the following components in parts by mass:

soybean rhizobium liquid: 200-300 parts;

bacillus liquid a: 170-240 parts;

bacillus liquid b: 130-180 parts;

silk fibroin: 50-80 parts;

peptone: 30-50 parts;

soybean lecithin: 8-12 parts;

trehalose: 100-150 parts;

chitosan oligosaccharide: 0.8-1.2 parts;

proline: 0.05-0.15 part;

gamma-aminobutyric acid: 0.1 to 0.5 portion

Purified water: 150 and 200 portions.

Preferably, the rhizobium japonicum liquid is one or more selected from rhizobium japonicum, rhizobium meliloti and rhizobium leguminosarum, and the viable count is more than or equal to 20X10⁸cfu/mL。

Preferably, the bacillus a liquid is one or more of bacillus licheniformis and bacillus subtilis, and the viable count is more than or equal to 20X10⁸cfu/mL; the bacillus liquid b is one or more of bacillus megaterium and bacillus sphaericus, and the viable count is more than or equal to 20X10⁸cfu/mL。

Preferably, the silk fibroin is a film-forming agent with the molecular weight of 600-5500 Da; wherein the part of 2000-5000Da accounts for 70-80%, and the mesh number is 100-200; the content is more than or equal to 99 percent, and the water content is less than or equal to 5 percent.

Preferably, the chitosan oligosaccharide is enzymolysis chitosan oligosaccharide from shrimp and crab shells, and has a molecular weight of 2000-.

Preferably, the proline is powdery proline with the purity of more than or equal to 99 percent; the gamma-aminobutyric acid is a gamma-aminobutyric acid solution with the purity of 450 g/L.

Please refer to fig. 1 and fig. 2; the invention also discloses a preparation method of the seed coating agent for promoting leguminous seeds to germinate into seedlings in saline-alkali soil, which is applied to the production of the seed coating agent for promoting leguminous seeds to germinate into seedlings in saline-alkali soil, and the preparation method comprises the following steps:

s1, mixing the soybean rhizobium liquid, the bacillus a liquid and the bacillus b liquid according to a ratio, and stirring to obtain a solution A;

s2, weighing a certain mass of purified water, sequentially adding silk fibroin, peptone and soybean lecithin, stirring for 30min at a rotation speed of 150-;

and S3, mixing the solution A and the solution B according to the proportion, and stirring to obtain the seed coating agent.

Preferably, in step S1, the rhizobium japonicum liquid, the bacillus a liquid and the bacillus b liquid are mixed in a ratio of 5:4:3, and stirred for 2-3 minutes at a rotation speed of 150-.

Preferably, in step S3, the solution A and the solution B are mixed according to the ratio of 7:3, and stirred for 20-30 minutes at the rotation speed of 150-;

the invention has the beneficial effects that: compared with the prior art, the invention has the following advantages:

1. the special film microenvironment can provide enough hydration by relieving oxidative stress and keep the configuration of biological molecules under the anhydrous condition so as to effectively preserve the biological activity, and the trehalose is used as a pressure protective agent, can help the microorganisms to resist osmotic pressure and drying stress, can relieve abiotic stress (such as drought stress, saline-alkali stress and low-temperature stress) and can obviously promote the germination and growth of seeds;

2. the prepared seed coating agent has no environmental pollution, no addition of chemical fertilizer, pesticide and plant growth regulator, and the film does not influence the activity of seeds and spores, is safe to use, and can obviously promote the germination of leguminous seeds;

3. the preparation method has simple process, small equipment investment and low cost, and the prepared film seed has uniform coating, good molding property, strong adhesive force and stable product;

4. the seeds are inoculated with bacillus with antagonism through the seed wrapping treatment, the bacillus metabolizes to generate lipopeptide antibiotics to block the invasion of pathogenic bacteria, a protective layer is formed around the plants, and the seeds are prevented from rotting and seedlings are prevented from withering.

5. The coated seeds have long storage period, and the coated seeds are suitable for machine sowing and meet the requirement of good seed marking.

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 some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a flow chart of the steps of the present invention;

FIG. 2 is a view showing the observation of a nodule under a fluorescence microscope.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. 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.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or the orientations or positional relationships that the products of the present invention are conventionally placed in use, and are only used for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal", "vertical", "suspended", and the like do not imply that the components are required to be absolutely horizontal or suspended, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Some embodiments of the invention are described in detail below with reference to the accompanying drawings. The embodiments described below and the features of the embodiments can be combined with each other without conflict.

Referring to fig. 1, the invention discloses a seed coating agent for promoting leguminous seeds to germinate into seedlings in saline-alkali soil, which comprises the following components in parts by weight: soybean rhizobium liquid: 200-300 parts; bacillus liquid a: 170-240 parts; bacillus liquid b: 130-180 parts; silk fibroin: 50-80 parts; peptone: 30-50 parts; soybean lecithin: 8-12 parts; trehalose: 100-150 parts; chitosan oligosaccharide: 0.8-1.2 parts; proline: 0.05-0.15 part; gamma-aminobutyric acid: 0.1-0.5 parts of purified water: 150 and 200 portions.

The rhizobium japonicum liquid is selected from one or more of rhizobium japonicum, rhizobium meliloti and rhizobium leguminosarum, and the viable count is more than or equal to 20X10⁸cfu/mL; the Bacillus alpha solution is one or more of Bacillus licheniformis and Bacillus subtilis, and the viable count is not less than 20X10⁸cfu/mL; the bacillus liquid b is one or more of bacillus megaterium and bacillus sphaericus, and the viable count is more than or equal to 20X10⁸cfu/mL. The silk fibroin is a film-forming agent with the molecular weight of 600-5500 Da; wherein the part of 2000-5000Da accounts for 70-80%, and the mesh number is 100-200; the content is more than or equal to 99 percent, and the water content is less than or equal to 5 percent. The chitosan oligosaccharide is enzymolysis chitosan oligosaccharide from shrimp and crab shells, and has a molecular weight of 2000-. The proline is powdery proline with the purity of more than or equal to 99 percent; the gamma-aminobutyric acid is a gamma-aminobutyric acid solution with the purity of 450 g/L. In this embodiment, the root nodule bacteria of soybean is needed to fix nitrogen for the leguminous plants, but the young soybean plants lack root nodule bacteria and cannot fix nitrogen from the air to meet the requirement of the young soybean plants, so that the young soybean plants may lack nutrition and die after being planted in saline-alkali soil,in order to solve the problem, the seed coating agent is added with the rhizobium japonicum, and the added rhizobium japonicum and rhizobium generated in the growing process of the leguminous plants are the same substance, so that the growth of the leguminous plants cannot be influenced.

The seed coating agent prepared by the method contains microorganisms, and peptone is used as a nutrient and a thickening agent, so that the added rhizobium japonicum, the bacillus a liquid and the bacillus b liquid have nutrient sources and can meet the nutrients required by growth and reproduction of the rhizobium japonicum, the bacillus a liquid and the bacillus b liquid, and substances generated by the microorganisms can be used as business sources required by growth and development of leguminous plants, so that the aim of coexistence is fulfilled; the silk fibroin is used as a film forming agent, and can effectively combine all substances together so as to be attached to the surface of the seed to effectively protect the seed, effectively prevent the volatilization of water, effectively maintain physical and chemical properties, participate in the stress resistance process of the seed, and protect plant growth-promoting bacteria to survive in a dry environment; in addition, the silk fibroin is matched with the oligochitosan, so that the enzyme can be immobilized, the larger the molecular weight is, the better the immobilization effect is, and the thermal stability of the immobilized enzyme is further improved; trehalose is used as a stabilizer to effectively resist the influence of external environment on the seed coating agent, and other substances such as proline, which are necessary application substances for seed germination or microbial propagation, are one of the components of plant protein and are mainly used as regulating substances of osmotic pressure in plant cytoplasm. The biological macromolecular structure can be stabilized, the ammonia toxicity can be removed, the cell acidity can be reduced, and the biological macromolecular structure can be used as an energy bank to adjust the redox potential of cells; simultaneously reflects the stress resistance of the plants, so the proline is added into the seed coating agent, and the stress resistance of the leguminous plants can be effectively enhanced

In addition, aiming at the existing seed coating agent, the long-term activity of the bacteria in the microbial seed coating agent is a main bottleneck, particularly plant growth promoting bacteria, the general survival rate of the bacteria under dry conditions is low, the application method of the saline-alkali resistant microbial seed coating agent generally adopts a seed dressing mode before sowing, seed soaking or seed dressing or only short-term or immediate sowing is adopted, the storage period is short, is not suitable for mechanical sowing and does not meet the requirement of good variety standard vertebration, and the silk fibroin is utilized to form the film forming agent, thereby effectively wrapping the microorganism, and having corresponding nutrient substances which can meet the requirement of the growth of the microorganism, thereby helping leguminous crops to improve the survival rate in saline-alkali stress, promoting seed germination and seedling growth, using safer bio-fertilizer and microorganism for sterilization, and realizing 0 addition of fertilizer, stimulin and pesticide, thereby reducing the burden of the environment. In addition, the invention adopts the biological material as the film forming agent, not only maintains physical and chemical properties, but also participates in the stress resistance process of the seeds, and protects the plant growth promoting bacteria to survive in a dry environment.

The invention is illustrated below by means of specific examples:

the first embodiment is as follows:

weighing corresponding raw materials according to the requirements of each component for later use; wherein the soybean rhizobium liquid: 250g of the total weight of the mixture; bacillus liquid a: 200g of the total weight of the mixture; bacillus liquid b: 150g of the total weight of the mixture; silk fibroin: 60g of the total weight of the mixture; peptone: 40g of the total weight of the mixture; soybean lecithin: 10g of a mixture; trehalose: 120g of a mixture; chitosan oligosaccharide: 1g of a compound; proline: 0.1 g; gamma-aminobutyric acid: 0.3g, purified water: 168.6 g; then mixing the soybean rhizobium liquid, the bacillus a liquid and the bacillus b liquid according to the ratio of 5:4:3, mixing in proportion, stirring for 2min at the rotating speed of 150 rpm to prepare solution A; secondly, weighing 168.6g of water, sequentially adding silk fibroin, peptone and soybean lecithin, stirring for 30min at the rotating speed of 150 revolutions/min, sequentially adding trehalose, chitosan oligosaccharide, proline and gamma-aminobutyric acid, mixing, stirring for 30min at the rotating speed of 200 revolutions/min, and preparing a solution B; and finally, mixing the solution A and the solution B according to the ratio of 7:3, stirring for 20min at the rotating speed of 200 r/min to obtain the seed coating agent.

Example two:

weighing corresponding raw materials according to the requirements of each component for later use; wherein the soybean rhizobium liquid: 300g of the total weight of the mixture; bacillus liquid a: 240 g; bacillus liquid b: 180 g; silk fibroin: 80g of the total weight of the mixture; peptone: 50g of the total weight of the mixture; soybean lecithin: 12g of a mixture; trehalose: 150g of the total weight of the mixture; chitosan oligosaccharide: 1.2 g; proline: 0.15 g; gamma-aminobutyric acid: 0.5g, purified water: 196.15 g; then mixing the soybean rhizobium liquid, the bacillus a liquid and the bacillus b liquid according to the ratio of 5:4:3, mixing in proportion, stirring for 2min at the rotating speed of 200 r/min to prepare a solution A; secondly, 196.15g of water is weighed, silk fibroin, peptone and soybean lecithin are sequentially added and stirred for 30min at the rotating speed of 150 r/min, trehalose, chitosan oligosaccharide, proline and gamma-aminobutyric acid are sequentially added and mixed, and stirring is carried out for 30min at the rotating speed of 200 r/min, so as to prepare solution B; and finally, mixing the solution A and the solution B according to the ratio of 7:3, stirring for 20min at the rotating speed of 200 r/min to obtain the seed coating agent.

Example three:

weighing corresponding raw materials according to the requirements of each component for later use; wherein the soybean rhizobium liquid: 250g of the total weight of the mixture; bacillus liquid a: 20g of the total weight of the mixture; bacillus liquid b: 150g of the total weight of the mixture; silk fibroin: 60g of the total weight of the mixture; peptone: 40g of the total weight of the mixture; soybean lecithin: 10g of a mixture; trehalose: 120g of a mixture; chitosan oligosaccharide: 1g of a compound; proline: 0.1 g; gamma-aminobutyric acid: 0.3g, purified water: 168.6 g; then mixing the soybean rhizobium liquid, the bacillus a liquid and the bacillus b liquid according to the ratio of 5:4:3, mixing in proportion, stirring for 2min at the rotating speed of 150 rpm to prepare solution A; secondly, weighing 168.6g of water, sequentially adding silk fibroin, peptone and soybean lecithin, stirring for 30min at the rotating speed of 150 revolutions/min, sequentially adding trehalose, chitosan oligosaccharide, proline and gamma-aminobutyric acid, mixing, stirring for 30min at the rotating speed of 200 revolutions/min, and preparing a solution B; and finally, mixing the solution A and the solution B according to the ratio of 7:3, stirring for 20min at the rotating speed of 200 r/min to obtain the seed coating agent

Weighing corresponding raw materials according to the requirements of each component for later use; wherein the soybean rhizobium liquid: 220g of a mixture; bacillus liquid a: 176 g; bacillus liquid b: 132 g; silk fibroin: 500 g; peptone: 30g of the total weight of the mixture; soybean lecithin: 8g of the total weight of the mixture; trehalose: 100g of the total weight of the mixture; chitosan oligosaccharide: 0.8 g; proline: 0.05 g; gamma-aminobutyric acid: 0.1g, purified water: 150.05 g; then mixing the soybean rhizobium liquid, the bacillus a liquid and the bacillus b liquid according to the ratio of 5:4:3, mixing in proportion, stirring for 2min at the rotating speed of 200 r/min to prepare a solution A; weighing purified water, sequentially adding silk fibroin, peptone and soybean lecithin, stirring for 30min at the rotation speed of 150 r/min, sequentially adding trehalose, chitosan oligosaccharide, proline and gamma-aminobutyric acid, mixing, stirring for 30min at the rotation speed of 200 r/min, and preparing solution B; and finally, mixing the solution A and the solution B according to the ratio of 7:3, stirring for 20min at the rotating speed of 200 r/min to obtain the seed coating agent.

After obtaining the seed coating agent, mixing the obtained seed coating agent and soybean seeds according to the ratio of 1: (30-40), fishing out the seeds after wrapping, spreading and airing or drying at 35 ℃, and finally obtaining the soybean seeds which can be sowed by a machine.

Relevant experiments were carried out with the seed coating obtained in the first example, and full, uniform soybean seeds were carefully selected, according to the seed coating: soaking and coating seeds in a mass ratio of 1:40, spreading and airing to be completely dry, then preparing a small plastic pot with the diameter of 20cm and the height of 20cm by taking the uncoated soybean seeds as a reference, filling the small plastic pot with soil which is dried and sieved by 1cm, sowing 50 seeds in each pot, dividing the pots into two groups, irrigating the soil by using clean water in one group, irrigating the soil by using 180mm/L saline solution in one group until the seeds are thoroughly irrigated, and repeating the treatment for 4 times in each group. After sowing, the seeds were placed at 23/18 deg.C (day/night) and the illumination was 160umol/m²The cultivation is carried out in a lighting incubator with the cultivation time of 2 weeks, the germination number is recorded on the 5 th day after sowing, the seedling number, the stem length, the stem thickness and the biomass of the soybean are measured after 2 weeks of sowing, and the root nodule and nodule conditions are observed, and the result is as follows:

it can be seen from the table that the germination rate, seedling rate, stem length, stem thickness and biological weight of soybean seeds using the seed coating agent of the present invention are respectively improved by 14.9%, 19.6%, 2.5%, 28.7% and 36.7% in the conventional soil environment compared with the control. Compared with the control of germination rate, seedling rate, stem length, stem thickness and biological weight, the germination rate, the seedling rate, the stem length, the stem thickness and the biological weight are respectively increased by 38.5%, 67.3%, 30.7%, 44.6% and 28.8% in the saline soil environment, the germination and growth of soybean seeds are still obviously improved even in the saline soil environment, and the effect is more obvious compared with that of conventional soil.

In addition, the soybean root nodule nodules are observed through a fluorescence microscope, the overground parts of the seeds treated by the seed coating agent grow well, have denser and longer root systems and have the root nodule nodules, the formation of the root nodule nodules is evaluated through visual observation and the fluorescence microscope, and particularly in saline soil, the seed coating agent has more obvious effects of promoting seed germination and seedling thriving.

Comparative example one:

weighing corresponding raw materials according to the requirements of each component for later use; wherein the soybean rhizobium liquid: 200g of the total weight of the mixture; bacillus liquid a: 200g of the total weight of the mixture; bacillus liquid b: 150g of the total weight of the mixture; silk fibroin: 60g of the total weight of the mixture; peptone: 40g of the total weight of the mixture; soybean lecithin: 10g of a mixture; trehalose: 120g of a mixture; chitosan oligosaccharide: 1g of a compound; proline: 0.1 g; gamma-aminobutyric acid: 0.3g, purified water: 168.6 g; then, mixing the soybean rhizobium liquid, the bacillus a liquid and the bacillus b liquid according to the ratio of 4: 4:3, mixing in proportion, stirring for 2min at the rotating speed of 150 rpm to prepare solution A; secondly, weighing 168.6g of water, sequentially adding silk fibroin, peptone and soybean lecithin, stirring for 30min at the rotating speed of 150 revolutions/min, sequentially adding trehalose, chitosan oligosaccharide, proline and gamma-aminobutyric acid, mixing, stirring for 30min at the rotating speed of 200 revolutions/min, and preparing a solution B; and finally, mixing the solution A and the solution B according to the ratio of 7:3, stirring for 20min at the rotating speed of 200 r/min to obtain the seed coating agent.

Comparative example two:

weighing corresponding raw materials according to the requirements of each component for later use; wherein the soybean rhizobium liquid: 250g of the total weight of the mixture; bacillus liquid a: 200g of the total weight of the mixture; bacillus liquid b: 150g of the total weight of the mixture; silk fibroin: 60g of the total weight of the mixture; peptone: 40g of the total weight of the mixture; soybean lecithin: 10g of a mixture; trehalose: 120g of a mixture; chitosan oligosaccharide: 1g of a compound; proline: 0.1 g; gamma-aminobutyric acid: 0.3g, purified water: 168.6 g; then, mixing the soybean rhizobium liquid, the bacillus a liquid and the bacillus b liquid according to the ratio of 4: 4:3, mixing in proportion, stirring for 2min at the rotating speed of 150 rpm to prepare solution A; secondly, weighing 168.6g of water, sequentially adding silk fibroin, peptone and soybean lecithin, stirring for 30min at the rotating speed of 150 revolutions/min, sequentially adding trehalose, chitosan oligosaccharide, proline and gamma-aminobutyric acid, mixing, stirring for 30min at the rotating speed of 200 revolutions/min, and preparing a solution B; and finally, mixing the solution A and the solution B according to the ratio of 1: 1, stirring for 20min at the rotating speed of 200 r/min to obtain the seed coating agent.

Species prepared in example one, comparative example one and comparative example twoThe coating agent was tested under the same conditions, i.e. selecting full, uniform soybean seeds, according to the coating agent: soaking and coating seeds in a mass ratio of 1:40, spreading and airing to be completely dry, then preparing a small plastic pot with the diameter of 20cm and the height of 20cm by taking the uncoated soybean seeds as a reference, filling the small plastic pot with soil which is dried and sieved by 1cm, sowing 50 seeds in each pot, dividing the pots into two groups, irrigating the soil by using clean water in one group, irrigating the soil by using 180mm/L saline solution in one group until the seeds are thoroughly irrigated, and repeating the treatment for 4 times in each group. After sowing, the seeds were placed at 23/18 deg.C (day/night) and the illumination was 160umol/m²The cultivation is carried out in a lighting incubator with the cultivation time of 2 weeks, the germination number is recorded on the 5 th day after sowing, the seedling number, the stem length, the stem thickness and the biomass of the soybean are measured after 2 weeks of sowing, and the root nodule and nodule conditions are observed, and the result is as follows:

firstly, compared with the first comparative example, the first example adjusts the amount of the rhizobium japonicum liquid, reduces the addition amount of the rhizobium japonicum, and the nutrition of the soybeans is mainly provided by the nutrient substances carried in the seeds in the germination stage, so the germination rates of the soybeans and the rhizobium japonicum liquid are close to each other, but the required nutrition needs to be obtained from the outside after the seeds germinate, and the rhizobium japonicum contained in the seeds is less, so the seedling rate, the stem length, the stem thickness and the like of the seeds are obviously lower than those of the first example; while the amount of nutrients was increased while reducing the microorganisms as compared with the comparative example two, it was found that the amount of the dry weight of the stem, stem thickness, or seedling was significantly superior to that of the first example, which may be due to the fact that the amount of the microorganisms was small and the amount of the nutrients consumed was small, so that the remaining nutrients were absorbed by the soybeans, which is equivalent to fertilizing the soybeans, so that the stem length or stem thickness of the soybeans were improved, but for the legume, the stem length or stem thickness was not too large, because if the stem length was too large, the lodging resistance of the beans was poor, and if the stem thickness was too large, the main nutrition of the legume was likely to act on the growth of the leaves and the rhizome and thus no more pods were produced, thereby reducing the economic efficiency; the comparison of the germination rates shows that the normal soil germination rate of the comparative example II is obviously lower than that of the example I, which probably results in that the amount of the microorganisms is further reduced, so that toxic and harmful microorganisms in the soil cannot be cleaned in time, the germination rate of the seeds is reduced easily, so that the seeds cannot germinate due to the infected harmful microorganisms, and in the saline soil, the influence is small due to the existence of fewer microorganisms, so that the germination rates of the two are close; in addition, for the seedling rate, because the beneficial microorganisms are fewer, the harmful microorganisms which can be removed are limited, the process from germination to seedling of the soybeans can be interfered, namely, the harmful microorganisms infect the soybeans in the seedling bud state, so that the soybeans cannot grow normally, and in saline-alkali soil, because the harmful microorganisms are fewer and the nutrient substances are more, the nutrient substances are increased for the soybean seedlings, and the seedling rate is increased.

The invention has the advantages that:

1) the biological material is innovatively used as the film forming material, so that a protective film required by the seeds is provided, and the abiotic stress on the seeds can be relieved through the unique protein structure of the biological material.

2) The bio-fertilizer and the microbial bactericide are accurately conveyed, and pesticides and fertilizers are not added, so that the use of the pesticides and the fertilizers is reduced, the environment is protected, and the soil degradation is delayed.

3) The film formed by the invention not only helps the seeds resist abiotic stress outside the soil, but also can form a protective layer around the rhizosphere when the seedlings grow, thereby further reducing the harm of the abiotic stress to the seedlings.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

The above disclosure is only for a few specific embodiments of the present invention, but the present invention is not limited thereto, and any variations that can be made by those skilled in the art are intended to fall within the scope of the present invention.