CN104430307A - Micro-capsulated suspended microbial seed coating agent and preparation method thereof - Google Patents

Abstract

The invention relates to a microencapsulated suspension microbial seed coating agent and a preparation method thereof. The microencapsulated suspension microbial seed coating agent contains functional bacteria microcapsules and auxiliary agents. Using endogenous emulsification method to prepare functional bacteria microcapsules with wall materials such as sodium alginate and gelatin, the particle size of the microcapsules is 20-60 μm, the content of functional bacteria is ≥10 ⁹ cfu/g, and the embedding rate is over 80%. The functional microorganisms are selected from two or more of Pseudomonas, Bacillus subtilis, Bacillus amyloliquefaciens, Enterobacter cloacae, Raoultella phytogenes, and Bacillus atrophaeus. The auxiliaries include one or more of film-forming agents, dispersants, tackifiers, antifreeze agents, and colorants. The finished product is obtained by uniformly mixing the prepared functional bacteria microcapsules with auxiliary agents. The product has the advantages of good film-forming properties, high bacterial persistence and viability, good slow-controlled release, strong application stability, environmental friendliness and convenient use. It can be used to promote seed germination and seedling growth of cotton, soybean, wheat, tomato, etc., control seedling diseases, and improve stress resistance.

Description

A kind of microencapsulated suspension microbial seed coating agent and preparation method thereof

technical field

The invention relates to a biological seed coating agent, in particular to a microencapsulated suspension microbial seed coating agent and a preparation method. The invention belongs to the technical field of agricultural biological preparation production.

Background of the invention

Biological seed coating agent is a seed coating agent made by fermentation and dosage form processing by using various bioactive ingredients produced or expressed by antagonistic microorganisms and their genes. Biological seed coating agent can improve the compatibility between seeds and soil, build a beneficial microbial environment, increase the germination rate of seeds, promote crop growth, and enhance stress resistance. The utility model has a wide application range and can be widely applied to various crop seeds. It decomposes quickly in nature, has no residue, no pollution, good safety, and has no negative impact on humans, animals or seeds. therefore. The active development of biological seed coating agents and the partial replacement of chemical seed coating agents have become a research hotspot in the sustainable development of green agriculture. The use of biocontrol fungi, bacteria and other antagonistic microorganisms to make biological agents has been widely used in the biological control and growth promotion of crop diseases and insect pests. These biological agents have been successfully incorporated into seed coatings, and their biological activity is maintained. The development of biological seed coatings provides broad prospects for the application of biological control.

At present, the ZSB biological seed coating agent of Zhefeng brand is more successful in the research of biological seed coating agent in my country, which was patented in 1990. Generally, it can increase the yield of rice by 5%-7%, corn by 8%-10%, wheat by 5%-10%, rapeseed by 5%-10%, watermelon by more than 10%, and the yield of cotton, radish, vegetables, beans, etc. 6%-10%, and can reduce rice bacterial stripe disease, bacterial blight, sheath blight, bakanae disease, kenaf anthracnose, jute blight, corn dwarf disease, wheat head blight and other crops disease. In addition, studies have shown that mixing ZSB biological seed coating agent and GA to coat corn seeds has a significant promotion effect on corn seed germination and seedling growth. Qu Zhonghua et al. used the fermented liquid of the REMI mutant strain of Trichoderma T23 as the main raw material to prepare a biotype seed coating agent to treat cucumber seeds. The results showed that the biotype seed coating agent can significantly improve the systemic resistance of cucumber seedlings to powdery mildew The relative control effect is up to 70% (Qu Zhonghua, Xue Chunsheng, Liu Lixing, etc. Preliminary study on the proteomics of cucumber leaves induced by biotype seed coating agents [J]. Anhui Agricultural Sciences, 2007, 35(21): 6487-6489) . The BA biospecies pesticide researched by Fang Xin et al. is compounded by a variety of bacteria and actinomycetes that have the functions of nitrogen fixation, phosphorus solubilization and potassium solubilization respectively. Bacillus, Bacillus colloidus, Streptomyces jingyang mixed preparation (Fang Xin, Wang Zhixue, Feng Jian. Application effect of BA biological seed coating agent on tomato [J]. Shandong Agricultural Science. 2005 (1): 55 -56). Its main function is to fix and decompose nutrients in the air and soil that cannot be absorbed by crops, increase the ability of crops to absorb nutrients in the soil, make the root system of crops developed, the plants strong, the incidence of disease is low, and the resistance is strong.

However, the active ingredients in biological seed coating agents are easily affected by the environment, especially the impact of some chemical additives, which often produce antibacterial effects, resulting in low effective bacteria content in biological seed coating agents, which cannot meet the requirements, and The stability of biological seed coating agents is easily affected by the environment, and there are problems such as short duration of action and poor stability, which greatly limit the practical application.

Pesticide microcapsules, as a sustained-release agent for pesticides, use polymer materials as capsule wall materials. Through physical, chemical or physicochemical methods, the active ingredients of pesticides can be highly dispersed into particles of several to hundreds of microns. Through Cover and fix with polymer compound to form microcapsules with certain wrapping strength. Microcapsule dosage form is one of the important directions for the development of pesticide dosage forms today. It has the following prominent advantages: (1) Pesticide microcapsule suspension has controlled release. Utilization efficiency, thereby reducing the cost of medication. Second, it reduces the pressure of pesticides on the environment. (2) Improve the physical and chemical stability of the preparation. In the microcapsule preparation, because it has the protective effect of the capsule wall material, it prevents the chemical substances inside the preparation from contacting the environmental components. It makes the preparation more stable and ensures the efficacy of the medicine. (3) It has a long storage period. Due to the special preparation of microcapsules, it avoids the decomposition or loss of active ingredients of pesticides by environmental factors such as light, heat, air, rain, soil, microorganisms, etc. Conventional dosage forms have a longer shelf life. (4) Prolonging the effective period, the active ingredients in the microcapsule dosage form are released continuously for a long time, so that the drug effect can be fully brought into play. Therefore, the preparation technology of microcapsules belongs to the one with the highest technical content in the pesticide formulations, and will certainly become an important development direction of pesticide formulations.

In view of the many advantages of the microcapsule dosage form, this dosage form is introduced into the new technology development idea of microbial seed coating agents, so as to better solve the problems of low number of viable bacteria, poor application stability, and long-lasting effect of microbial seed coating agents. Short, high consumption and high cost. However, literature and published patent searches show that the development technology of microencapsulated suspended microbial seed coating agents has not been reported at home and abroad. Therefore, the present invention microencapsulates functional microorganisms by selecting suitable environment-friendly and degradable wall materials to prepare bacterial cell microcapsules, and then adds film-forming agents, dispersants, tackifiers, antifreeze agents and coloring agents to develop Developed a new type of microencapsulated suspension microbial seed coating agent, through the protection of the microcapsule wall material on the living bacteria, thereby reducing the adverse effects of the environment and additives on microorganisms, and ensuring the effective bacterial content of the microbial seed coating agent . At the same time, it has the characteristics of slow and controlled release, realizing the high persistence and stability of live bacteria. In addition, the microbial seed coating agent has the advantages of good film-forming property and convenient use, and is very suitable for the coating treatment of cotton, soybean, wheat, tomato and other seeds, and can effectively promote seed germination and seedling growth, control seedling diseases, and improve crop Stress resistance and so on. It will have broad promotion and application prospects, and has good economic, ecological and social benefits.

Contents of the invention

The purpose of the present invention is to utilize some natural macromolecule compounds as sodium alginate, starch, xanthan gum, cellulose, gelatin etc. as wall material, embed function microorganism with endogenous emulsification method, prepare thalline microcapsule suspension, then Composite film-forming agent, dispersant, thickener, antifreeze agent, and coloring agent, etc., to develop a new type of microencapsulated suspension microbial seed coating agent. It has the advantages of good film-forming property, high bacterial persistence and viability, good slow-controlled release, strong application stability, environmental friendliness and convenient use. It can be used to promote seed germination and seedling growth of cotton, soybean, wheat, tomato, etc., control seedling diseases, and improve stress resistance. The object of the present invention is to be realized through the following technical solutions.

The invention relates to a microencapsulated suspension microbial seed coating agent, which comprises functional bacterial strain microcapsules and auxiliary agents.

The preparation method of the described functional strain microcapsules is an endogenous emulsification method, and the steps are as follows:

Measure a certain concentration of wall material compound solution, add calcium carbonate particles, mix and stir the fermentation liquid of functional microorganisms and wall material solution evenly to form a suspension; add this suspension to vegetable oil (including Span80) according to a certain water-to-oil ratio , emulsify under the action of stirring to form a water-in-oil emulsion; add a certain amount of glacial acetic acid to lower the pH value of the system, continue the reaction for 20 minutes, add CaCl ₂ solution and stir, and it can be observed that the bacterial microcapsules are formed in the solution. The balls are recovered after standing to remove the oil phase, and the wet microcapsule suspension of bacteria is obtained by collecting, and the effective bacteria content in the microcapsules is ≥10 ⁹ cfu/g.

The mass percentage of the components for preparing the microcapsules is as follows: the wall material compound is composed of sodium alginate 0.5%-3%, gelatin 1%-3%, xanthan gum 0-2%, starch 0%-4% , calcium carbonate 1%-3%, Span80 0.5%-1%, calcium chloride 2%-4%, bacterial liquid 25%-50%, vegetable oil 25%-50%, glacial acetic acid 5%-10%.

Functional microorganisms are selected from functional microorganisms that have the functions of disease prevention and growth promotion and salt solution promotion, such as Pseudomonas (SRPG-396CGMCC No.9397), Bacillus subtilis (DPPG-26 CGMCC No.9393), Bacillus amyloliquefaciens (DPPG Two of -74CGMCC No.9396), Enterobacter cloacae (SRPG-70 CGMCC No.9395), Raoultella vegetativeum (SRPG-4CGMCC No.9392), Bacillus atrophaeus (DPPG-28 CGMCC No.9394) or several.

The auxiliary agent includes one or more of film-forming agent, dispersant, tackifier, antifreeze agent and coloring agent.

The mass percent composition of each composition of described microbial seed coating agent is:

In the described auxiliary agent, the film-forming agent is one or more of sodium alginate, polyacrylamide, polyvinyl alcohol; the dispersant is one of lignin, sodium lauryl sulfate, Tween 80, The thickener is one of gelatin, sodium carboxycellulose, and gum arabic, the antifreeze agent is one of ethylene glycol, glycerin, and propylene glycol, and the colorant is carmine, saffron, rhodamine B, and acid fuchsin. kind of.

A kind of preparation method of microencapsulated suspended microbial seed coating agent of the present invention is characterized in that it is prepared according to the following steps or order:

(a) After dissolving one or more of sodium alginate and polyvinyl alcohol in water, a film-forming agent is prepared;

(b) Other auxiliary ingredients can also be added, including dispersants, antifreeze agents, colorants and film forming agents, which are stirred and mixed together to form auxiliary agents;

(c) Mixing the prepared auxiliary agent with the obtained cell microcapsule suspension, and mechanically stirring to obtain a finished product. Its mass percentage content is 60-80% of auxiliary agent and 20%-40% of microcapsule suspension.

The functional microorganisms in the present invention are prepared by a conventional method, strain-incline-shake flask-seed tank-fermentation tank-concentration. The obtained functional microbial fermentation broth has a live bacterial concentration of 10 ¹⁰ -10 ¹³ cfu/mL, and can be used as an active ingredient of a microbial seed coating agent.

The invention also provides a method for coating seeds with the product, comprising uniformly mixing the seeds and the microencapsulated suspension microbial seed coating agent of the invention in a certain proportion, and air-drying the obtained coated seeds at room temperature. Depending on the type of seed, the ratio of biological seed coating agent to seed can be selected from the range of 2%-8%. The index of the finished product of the microencapsulated suspended microbial seed coating agent of the present invention is compared with the national standard index of the seed coating agent in the following table.

Table 1 The performance index of the seed coating agent product developed by the present invention is compared with the national standard index

Compared with the prior art, the present invention has the following advantages:

The microencapsulated suspended microorganism seed coating agent of the present invention is a novel environment-friendly seed coating agent. Environmentally friendly and degradable wall materials are preferred to microencapsulate functional microorganisms, reducing the adverse effects of the environment and additives on microorganisms, and ensuring the effective bacterial content of biological seed coating agents. Some indexes of the product of the present invention are better than those of the national standard. Moreover, the product has the advantages of good film-forming property, high bacterial persistence and viability, good slow-controlled release, strong application stability, environmental friendliness, convenient use, high efficiency, low toxicity and no residue. It can be used to promote seed germination and seedling growth of cotton, soybean, wheat, tomato, etc., control seedling diseases, and improve stress resistance. The technology and product will have broad prospects for popularization and application.

Description of drawings

Figure 1 Microcapsules observed under an optical microscope.

Detailed ways

The invention will be further described in detail below through specific examples. The following examples are only descriptive, not restrictive, and cannot limit the protection scope of the present invention with this.

Microcapsule Preparation Example 1

Mix Bacillus amyloliquefaciens strain (DPPG-74 CGMCC No.9396) and Bacillus subtilis (DPPG-26 CGMCC No.9393) at a ratio of 2:1 and ferment to obtain a live bacteria concentration of 10 ^10-13 cfu/mL The fermented broth is ready for use.

Bacterial microcapsules were prepared by endogenous emulsification method. Prepare 2% sodium alginate and 1% gelatin into solutions, mix them evenly, add 2% calcium carbonate particles, mix 25% of the fermented liquid of functional microorganisms with the composite wall material solution, and stir evenly to form a suspension; suspend the solution was added to 40% cottonseed oil (containing 0.5% Span80), emulsified under the action of magnetic stirring to form a water-in-oil emulsion; 5% glacial acetic acid was added to lower the pH value of the system, and the reaction was continued for 20 minutes, and 4% CaCl was added ₂ 50 mL of the solution, as shown in Figure 1, it can be observed that thalline microcapsules have formed in the solution, after standing, the oil phase is recovered and removed, and the thalline microcapsule suspension is collected.

The peak particle size of the prepared microcapsules is concentrated at 20-30 μm, the water content is 67.70%, the embedding rate is 82.22%, and the functional live bacteria content is >10 ⁹ cfu/g.

Microcapsule Preparation Example 2

Mix Bacillus amyloliquefaciens (DPPG-74 CGMCC No.9396), Bacillus subtilis (DPPG-26 CGMCC No.9393) and Enterobacter cloacae (SRPG-70 CGMCC No.9395) in a ratio of 2:1:2, Fermentation is carried out to obtain a fermentation broth with a viable bacterial concentration of 10 ^10-13 cfu/mL for subsequent use.

Preparation of microcapsules by endogenous emulsification method. Prepare 2% sodium alginate, 1.5% gelatin and 3% starch into solutions, mix well, add 2% calcium carbonate particles, mix 30% functional microbial fermentation broth with composite wall material solution, stir well, and form a suspension solution; add this suspension to 50% cottonseed oil (containing 0.5% Span80), and emulsify under the action of magnetic stirring to form a water-in-oil emulsion; add 5% glacial acetic acid to reduce the pH value of the system, and continue the reaction for 20 minutes , adding 50 mL of 3% CaCl _solution , it can be observed that microcapsules of thalline are formed in the solution, and after standing, the oil phase is recovered and removed, and the microcapsule suspension of thalline is collected.

The peak particle size of the prepared microcapsules is concentrated at 30-40 μm, the water content is 73.36%, the embedding rate is 88.89%, and the functional live bacteria content is >10 ⁹ cfu/mL.

Microcapsule Preparation Example 3

Mix Pseudomonas putida (SRPG-396 CGMCC No.9397) and Bacillus atrophaeus (DPPG-28 CGMCC No.9394) at a ratio of 1:1 and ferment to obtain a viable bacterial concentration of 10 ^10-13 cfu/mL The fermented broth is ready for use.

Preparation of microcapsules by endogenous emulsification method. Prepare 2% sodium alginate, 2% xanthan gum, and 3% starch into solutions, mix them evenly, add 2% calcium carbonate particles, mix 35% functional microbial fermentation broth with the composite wall material solution, and stir evenly. Form a suspension; join this suspension in 40% cottonseed oil (containing 0.5% Span80), carry out emulsification under the effect of magnetic stirring, form water-in-oil emulsion; Add 5% glacial acetic acid and reduce system pH value, continue After reacting for 20 minutes, add 50 mL of 4% CaCl ₂ solution, and it can be observed that bacterial cell microcapsule balls are formed in the solution. After standing still, the oil phase is recovered and removed, and the bacterial cell microcapsule suspension is collected.

The peak particle size of the prepared microcapsules is concentrated at 40-50 μm, the water content is 74.42%, the embedding rate is 87.78%, and the functional live bacteria content is >10 ⁹ cfu/mL.

Microcapsule Preparation Example 4

Mix Bacillus amyloliquefaciens strain (DPPG-74 CGMCC No.9396) and Raoultella plantarum (SRPG-4 CGMCC No.9392) in a ratio of 2:1, and ferment to obtain a viable bacterial concentration of 10 ^10-13 cfu/mL of fermentation broth for later use.

Preparation of microcapsules by endogenous emulsification method. Prepare 2% sodium alginate, 2% gelatin, 1% xanthan gum and 2% starch into solutions respectively, mix them evenly, add 3% calcium carbonate particles, and mix 40% of the fermented liquid of functional microorganisms with the composite wall material solution , stir evenly to form a suspension; add this suspension to 50% cottonseed oil (containing 0.5% Span80), and emulsify under the action of magnetic stirring to form a water-in-oil emulsion; add 5% glacial acetic acid to reduce the pH value, continue to react for 20 minutes, add 2% CaCl ₂ solution 50mL, it can be observed that bacterial cell microcapsule balls are formed in the solution, after standing, recover and remove the oil phase, collect and obtain bacterial cell microcapsule suspension.

The peak particle size of the prepared microcapsules is concentrated at 50-60 μm, the water content is 76.51%, the embedding rate is 91.11%, and the functional live bacteria content is more than 10 ⁹ cfu/mL.

Microorganism seed coating preparation embodiment 1

Dissolve 1% sodium alginate and 3% polyvinyl alcohol in water to prepare a film-forming agent, mix with 1% sodium lauryl sulfate, 0.3% gum arabic, 3% ethylene glycol, 0.15% rhodamine B, etc. Together, stir to combine into auxiliaries.

The thalline microcapsule suspension obtained in the preparation example 1 of the prepared auxiliary agent and the microcapsule is mixed according to 80% auxiliary agent and 20% microcapsule suspending agent (mass percentage), and evenly prepared by mechanical stirring. Invented microencapsulated suspension microbial seed coating agent. The measured performance indicators are: viscosity 450mPa·s (25°C), uniformity 92.36%, suspension rate 94.00%, film-forming time 9min, water-absorbing swelling property 53.5g/g, after 180d storage, functional live bacteria content > 10 ⁸ cfu /mL.

Next, 30 parts by weight of cotton seeds are mixed with one part by weight of the microencapsulated suspension microbial seed coating agent of the present invention, and air-dried outdoors to prepare cotton seeds coated with the microencapsulated suspended microbial seed coating agent. The functional microbial coating amount of the seed is more than 10 ⁶ cfu/seed, and the shedding rate is 4.6%.

Preparation Example 2 of Microbial Seed Coating Agent

After dissolving 2% sodium alginate and 3% polyvinyl alcohol in water, a film-forming agent was prepared, which was mixed with 2% sodium lauryl sulfate, 0.4% sodium carboxycellulose, 3% glycerin, 0.15% safranin, etc. Together, stir to combine into auxiliaries.

The prepared auxiliary agent is mixed with the bacterial cell microcapsule suspension obtained in Example 1 of microcapsule preparation according to 80% auxiliary agent and 20% microcapsule suspending agent (mass percentage), and is uniformly stirred by machinery to prepare the present invention. Microencapsulated suspension microbial seed coating agent. The measured performance indicators are: viscosity 462mPa·s (25°C), uniformity 94.36%, suspension rate 95.10%, film-forming time 8min, water absorption swelling 56.2g/g, after storage for 180d, functional live bacteria content> 10 ⁸ cfu /mL.

Next, 30 parts by weight of cotton seeds are mixed with one part by weight of the microencapsulated suspension microbial seed coating agent of the present invention, and air-dried outdoors to prepare cotton seeds coated with the microencapsulated suspended microbial seed coating agent. The functional microorganism coating amount of the seed is more than 10 ⁶ cfu/seed, and the shedding rate is 4.4%.

Preparation Example 3 of Microbial Seed Coating Agent

After dissolving 1% polyacrylamide and 3% polyvinyl alcohol in water, a film-forming agent was prepared, mixed with 3% lignin, 0.3% gelatin, 3% propylene glycol, 0.15% rhodamine B, etc., and stirred to form a film-forming agent. agent.

The prepared auxiliary agent is mixed with the bacterial cell microcapsule suspension obtained in Example 1 of microcapsule preparation according to 80% auxiliary agent and 20% microcapsule suspending agent (mass percentage), and is uniformly stirred by machinery to prepare the present invention. Microencapsulated suspension microbial seed coating agent. The measured performance indicators are: viscosity 478mPa·s (25°C), uniformity 95.21%, suspension rate 99.24%, film-forming time 7min, water-absorbing swelling property 54.1g/g, after 180d storage, functional live bacteria content > 10 ⁸ cfu /mL.

Next, 30 parts by weight of cotton seeds are mixed with one part by weight of the microencapsulated suspension microbial seed coating agent of the present invention, and air-dried outdoors to prepare cotton seeds coated with the microencapsulated suspended microbial seed coating agent. The functional microbial coating amount of the seed is more than 10 ⁶ cfu/seed, and the shedding rate is 4.3%.

Preparation Example 4 of Microbial Seed Coating Agent

Dissolve 1% polyacrylamide and 4% polyvinyl alcohol in water to prepare a film-forming agent, mix it with 1% lignin, 0.3% sodium carboxycellulose, 3% propylene glycol, 0.15% carmine, etc., and stir to mix into additives.

Mix the prepared auxiliary agent with the bacterium microcapsule suspension obtained in Example 2 of microcapsule preparation, mix according to 80% auxiliary agent, 20% microcapsule suspending agent (mass percentage), and evenly prepare the present invention through mechanical stirring. Microencapsulated suspension microbial seed coating agent. The measured performance indicators are: viscosity 485mPa·s (25°C), uniformity 93.36%, suspension rate 93.18%, film-forming time 8min, water absorption swelling 52.9g/g, after storage for 180d, functional live bacteria content > 10 ⁸ cfu /mL.

Next, 30 parts by weight of cotton seeds are mixed with one part by weight of the microencapsulated suspension microbial seed coating agent of the present invention, and air-dried outdoors to prepare cotton seeds coated with the microencapsulated suspended microbial seed coating agent. The functional microbial coating amount of the seed is more than 10 ⁶ cfu/seed, and the shedding rate is 3.6%.

Preparation Example 5 of Microbial Seed Coating Agent

After dissolving 1% sodium alginate and 5% polyacrylamide in water, a film-forming agent was prepared, which was mixed with 1% sodium lauryl sulfate, 0.3% gum arabic, 3% glycerin, 0.15% carmine, etc. Stir to combine into auxiliaries.

Mix the prepared auxiliary agent with the bacterial cell microcapsule suspension obtained in Example 2 of microcapsule preparation, mix according to 80% auxiliary agent and 20% microcapsule suspending agent (mass percentage), and evenly prepare this product through mechanical stirring. Invented microencapsulated suspension microbial seed coating agent. The measured performance indicators are: viscosity 502 mPa·s (25°C), uniformity 92.17%, suspension rate 90.16%, film-forming time 7 minutes, water absorption swelling 58.3g/g, after storage for 180 days, functional live bacteria content > 10 ⁸ cfu/mL.

Next, 30 parts by weight of cotton seeds are mixed with one part by weight of the microencapsulated suspension microbial seed coating agent of the present invention, and air-dried outdoors to prepare cotton seeds coated with the microencapsulated suspended microbial seed coating agent. The functional microbial coating amount of the seed is more than 10 ⁶ cfu/seed, and the shedding rate is 4.3%.

Preparation Example 6 of Microbial Seed Coating Agent

Dissolve 1% sodium alginate and 4% polyacrylamide in water to prepare a film-forming agent, mix with 2% sodium lauryl sulfate, 0.3% gum arabic, 3% ethylene glycol, 0.15% acid fuchsin, etc. Together, stir to combine into auxiliaries.

Mix the prepared auxiliary agent with the bacterium microcapsule suspension obtained in Example 2 of microcapsule preparation, mix according to 80% auxiliary agent, 20% microcapsule suspending agent (mass percentage), and evenly prepare the present invention through mechanical stirring. Microencapsulated suspension microbial seed coating agent. The measured performance indicators are: viscosity 486mPa·s (25°C), uniformity 93.26%, suspension rate 94.72%, film-forming time 7min, water-absorbing swelling property 59.2g/g, after storage for 180d, functional live bacteria content > 10 ⁸ cfu /mL.

Next, 30 parts by weight of cotton seeds are mixed with one part by weight of the microencapsulated suspension microbial seed coating agent of the present invention, and air-dried outdoors to prepare cotton seeds coated with the microencapsulated suspended microbial seed coating agent. The functional microbial coating amount of the seed is more than 10 ⁶ cfu/seed, and the shedding rate is 3.8%.

Preparation Example 7 of Microbial Seed Coating Agent

After dissolving 1% polyacrylamide and 5% polyvinyl alcohol in water, a film-forming agent is prepared, mixed with 2% lignin, 0.3% gelatin, 3% propylene glycol, 0.15% safranin, etc., and stirred to form an auxiliary agent .

Mix the prepared auxiliary agent with the bacterium microcapsule suspension obtained in Example 3 of microcapsule preparation, mix according to 80% auxiliary agent, 20% microcapsule suspending agent (mass percentage), and evenly prepare the present invention through mechanical stirring. Microencapsulated suspension microbial seed coating agent. The measured performance indicators are: viscosity 512mPa·s (25°C), uniformity 94.36%, suspension rate 96.74%, film-forming time 8min, water absorption swelling 56.2g/g, after storage for 180d, functional live bacteria content > 10 ⁸ cfu /mL.

Next, 30 parts by weight of cotton seeds are mixed with one part by weight of the microencapsulated suspension microbial seed coating agent of the present invention, and air-dried outdoors to prepare cotton seeds coated with the microencapsulated suspended microbial seed coating agent. The functional microbial coating amount of the seed is more than 10 ⁶ cfu/seed, and the shedding rate is 3.1%.

Preparation Example 8 of Microbial Seed Coating Agent

After dissolving 1% sodium alginate and 4% polyvinyl alcohol in water, a film-forming agent was prepared and mixed with 3% Tween 80, 0.3% sodium carboxycellulose, 3% glycerin, 0.15% rhodamine B, etc., Stir to combine into auxiliaries.

Mix the prepared auxiliary agent with the bacterium microcapsule suspension obtained in Example 3 of microcapsule preparation, mix according to 80% auxiliary agent, 20% microcapsule suspending agent (mass percentage), and evenly prepare the present invention through mechanical stirring. Microencapsulated suspension microbial seed coating agent. The measured performance indicators are: viscosity 493mPa·s (25°C), uniformity 94.76%, suspension rate 96.32%, film-forming time 8min, water absorption swelling 57.6g/g, after storage for 180d, functional viable bacteria content > 10 ⁸ cfu /mL.

Next, 30 parts by weight of cotton seeds are mixed with one part by weight of the microencapsulated suspension microbial seed coating agent of the present invention, and air-dried outdoors to prepare cotton seeds coated with the microencapsulated suspended microbial seed coating agent. The functional microbial coating amount of the seed is more than 10 ⁶ cfu/seed, and the shedding rate is 3.5%.

Microorganism seed coating preparation embodiment 9

Dissolve 1% sodium alginate and 5% polyvinyl alcohol in water to prepare a film-forming agent, mix it with 3% Tween 80, 0.3% gelatin, 3% ethylene glycol, 0.15% acid fuchsin, etc., and stir Mixed into auxiliaries.

The prepared auxiliary agent is mixed with the bacterium microcapsule suspension obtained in Example 4 of microcapsule preparation according to 80% auxiliary agent and 20% microcapsule suspending agent (mass percentage), and uniformly stirred by machinery to prepare the present invention. Microencapsulated suspension microbial seed coating agent. The measured performance indicators are: viscosity 507mPa·s (25°C), uniformity 92.36%, suspension rate 94.82%, film-forming time 9min, water absorption swelling 58.1g/g, after storage for 180d, functional live bacteria content > 10 ⁸ cfu /mL.

Next, 30 parts by weight of cotton seeds are mixed with one part by weight of the microencapsulated suspension microbial seed coating agent of the present invention, and air-dried outdoors to prepare cotton seeds coated with the microencapsulated suspended microbial seed coating agent. The functional microbial coating amount of the seed is more than 10 ⁶ cfu/seed, and the shedding rate is 4.1%.

In order to investigate the performance of seeds treated with microencapsulated suspended microbial seed coating agent, experiments were carried out under potted environmental conditions.

Test Example

After the microbial seed coating agent of Preparation Example 3 of the present invention and cotton seeds were coated with a ratio of 1:30 (w/w), the seeds were seed-dressed with the chemical pesticide pentachloronitrobenzene (PCNB), and sowed in a conventional manner. After 30 days of emergence, the emergence rate and incidence rate were investigated.

Table 2 Effects of microencapsulated suspended microbial seed coating agent on cotton seedling emergence and seedling stage

After the cotton seeds are coated with the microencapsulated suspended microorganism seed coating agent of the present invention, the emergence rate is obviously increased, while the disease incidence rate is significantly reduced. Compared with chemical pesticides, the plant height, fresh weight and dry weight of the treated plants are significantly improved, and the vegetative biomass of the plants can be effectively increased.

Claims (9)

1. A microencapsulated suspension microbial seed coating agent is characterized in that: it comprises functional bacterial strain microcapsules and auxiliary agents. 2. a kind of microencapsulation suspending microbial seed coating agent according to claim 1, is characterized in that: the preparation method of described functional bacterial strain microcapsule is endogenous emulsification method, and step is as follows: Measure a certain concentration of wall material compound solution, add calcium carbonate particles, mix and stir the fermentation liquid of functional microorganisms and wall material solution evenly to form a suspension; add this suspension to vegetable oil (including Span80) according to a certain water-to-oil ratio , emulsify under the action of stirring to form a water-in-oil emulsion; add a certain amount of glacial acetic acid to lower the pH value of the system, continue the reaction for 20 minutes, add CaCl ₂ solution and stir, and it can be observed that the bacterial microcapsules are formed in the solution. The balls are recovered after standing to remove the oil phase, and the cell microcapsule suspension is obtained by collecting, and the effective bacteria content in the microcapsules is ≥10 ⁹ cfu/g. 3. a kind of microencapsulated suspension microbial seed coating agent according to claim 2, is characterized in that: the mass percentage composition of described preparation microcapsule composition is: wall material compound is made of sodium alginate 0.5%-3 %, Gelatin 1%-3%, Xanthan Gum 0-2%, Starch 0%-4%, Calcium Carbonate 1%-3%, Span80 0.5%-1%, Calcium Chloride 2%-4%, Bacteria Liquid 25%-50%, vegetable oil 25%-50%, glacial acetic acid 5%-10%. 4. a kind of microencapsulated suspension microbial seed coating agent according to claim 2, is characterized in that: functional microorganism is selected from Pseudomonas, Bacillus subtilis, Bacillus amyloliquefaciens, Enterobacter cloacae, plant Raoul Two or more of Bacillus atrophaeus and Bacillus atrophaeus. 5. a kind of microencapsulation suspending microbial seed coating agent according to claim 1, is characterized in that: described auxiliary agent comprises one of film-forming agent and dispersant, viscosifier, antifreeze agent, coloring agent species or several. 6. a kind of microencapsulated suspension microbial seed coating agent according to claim 5, is characterized in that: the mass percentage composition of each composition of described microbial seed coating agent is: 7. a kind of microencapsulation suspending microbial seed coating agent according to claim 6, is characterized in that: in described auxiliary agent, film-forming agent is one of sodium alginate, polyacrylamide, polyvinyl alcohol or Various, dispersant is one of lignin, sodium lauryl sulfate, Tween 80, thickener is gelatin, sodium carboxycellulose, gum arabic, antifreeze is ethylene glycol, glycerin , propylene glycol, and the coloring agent is one of carmine, safranin, rhodamine B, and acid fuchsin. 8. A preparation method of a microencapsulated suspended microbial seed coating agent, characterized in that it is prepared in the following steps or order: (a) After dissolving one or more of sodium alginate, polyacrylamide and polyvinyl alcohol in water, a film-forming agent is prepared; (b) or add other auxiliary ingredients, including dispersants, antifreeze agents, colorants and film formers, and stir and mix them together to form auxiliary agents; (c) Mixing the prepared auxiliary agent with the obtained cell microcapsule suspension, and mechanically stirring to obtain a finished product. Its mass percentage content is 60-80% of auxiliary agent and 20%-40% of microcapsule suspension. 9. According to the application of the microencapsulated suspended microbial seed coating agent according to claim 8, it is characterized in that it effectively promotes seed germination and seedling growth such as cotton, soybean, wheat, tomato, controls seedling stage diseases, improves crop stress resistance, etc. effect.