阅读说明：本技术 光合细菌活菌粉剂及其制备方法和应用 (Photosynthetic bacteria live bacteria powder and preparation method and application thereof ) 是由 成飞雪 刘勇 张德咏 王东伟 王剑 程菊娥 朱春晖 谭新球 张松柏 唐蓓 孙书娥 于 2021-06-21 设计创作，主要内容包括：一种本发明的光合细菌活菌粉剂及其制备方法和应用,该光合细菌活菌粉剂的制备包括将冷冻干燥保护剂加入光合细菌培养液中,混匀,然后依次加入壳聚糖和海藻酸钠,使菌液变成浓稠状,再将浓稠状光合细菌菌液中加入高岭土,以吸收多余的水分,使光合细菌菌液变成泥浆状,再进行低温冷冻干燥,形成固状物,含水率保持在2.5％～3.0％,经粉碎过筛后,得到光合细菌活菌粉剂。本发明实现了光合细菌微生物制剂从菌剂到粉剂的飞跃,生产的光合细菌活菌粉剂不易感染杂菌、质量稳定,产品储存方便且储存时间长,运输成本大幅降低,可广泛用于农业生产。(The preparation method of the photosynthetic bacteria viable powder comprises the steps of adding a freeze-drying protective agent into a photosynthetic bacteria culture solution, uniformly mixing, then sequentially adding chitosan and sodium alginate to change the bacterial solution into a thick state, then adding kaolin into the thick photosynthetic bacteria bacterial solution to absorb excessive water to change the photosynthetic bacteria bacterial solution into a slurry state, then carrying out low-temperature freeze drying to form a solid state, keeping the water content at 2.5-3.0%, and crushing and sieving to obtain the photosynthetic bacteria viable powder. The invention realizes the leap of photosynthetic bacteria microbial preparation from microbial inoculum to powder, the produced photosynthetic bacteria live bacteria powder is not easy to infect mixed bacteria, the quality is stable, the product is convenient to store and long in storage time, the transportation cost is greatly reduced, and the photosynthetic bacteria microbial preparation can be widely used for agricultural production.)

1. A photosynthetic bacteria viable bacteria powder is characterized in that the photosynthetic bacteria viable bacteria powder is prepared by taking photosynthetic bacteria culture solution as a raw material, taking trehalose, ascorbic acid and sorbitol as freeze drying protective agents, taking chitosan and sodium alginate as thickening agents and taking kaolin as a solid filler.

2. A viable photosynthetic bacteria powder as claimed in claim 1, wherein the ratio of the photosynthetic bacteria culture solution, trehalose, ascorbic acid, sorbitol, chitosan, sodium alginate and kaolin is 100 mL: 0.5-1.0 g: 0.025 g-0.05 g: 0.05-0.1 g: 0.5-1.0 g: 1.0-1.5 g: 2.0 g-2.5 g, and the concentration of the photosynthetic bacteria culture solution is 1 x 10⁹cfu/mL～9×10⁹cfu/mL。

3. A live photosynthetic bacteria powder according to claim 1 or 2, characterized in that the live photosynthetic bacteria powder has a water content of 2.5 to 3.0%, a storage temperature of 4 to 42 ℃ and a storage time of 1 year.

4. A preparation method of photosynthetic bacteria live bacteria powder is characterized by comprising the following steps:

(1) adding a freeze-drying protective agent into a photosynthetic bacteria culture solution, wherein the freeze-drying protective agent is trehalose, ascorbic acid and sorbitol, and uniformly mixing to obtain a photosynthetic bacteria liquid containing the freeze-drying protective agent;

(2) sequentially adding chitosan and sodium alginate into the photosynthetic bacteria liquid containing the freeze-drying protective agent, and uniformly mixing to make the bacteria liquid become thick;

(3) adding kaolin into the thick photosynthetic bacteria liquid, mixing uniformly, absorbing excessive water, and changing the photosynthetic bacteria liquid from thick to slurry;

(4) freeze drying the slurry photosynthetic bacteria liquid to form solid matter with water content of 2.5-3.0%, crushing and sieving to obtain live photosynthetic bacteria powder.

5. A method for preparing viable photosynthetic bacteria powder as claimed in claim 4, wherein in the steps (1) to (3), the ratio of the photosynthetic bacteria culture solution, trehalose, ascorbic acid, sorbitol, chitosan, sodium alginate and kaolin is 100 mL: 0.5-1.0 g: 0.025-0.05 g: 0.05-0.1 g: 0.5-1.0 g: 1.0-1.5 g: 2.0-2.5 g.

6. A method for preparing viable photosynthetic bacteria powder according to claim 4 wherein in step (4), the freeze drying is vacuum freeze drying at-180 ℃ or freeze spray drying at-40 ℃.

7. Use of the live photosynthetic bacteria powder of any one of claims 1 to 3 or the live photosynthetic bacteria powder prepared by the preparation method of any one of claims 4 to 6 in agricultural production.

8. The use of claim 7, wherein the agricultural production comprises promoting crop growth and controlling crop diseases, the crop diseases including one or more of crop nematode disease, crop virus disease and rice blast disease.

Technical Field

The invention belongs to the field of microbial pesticide preparations, relates to photosynthetic bacteria live bacteria powder, a preparation method and application thereof, and particularly relates to photosynthetic bacteria live bacteria powder which is protected by low-temperature freezing and is suitable for low water content, and a preparation method and application thereof.

Background

Photosynthetic Bacteria (PSB) are the first prokaryotic organisms that are capable of photosynthesis that occur on earth and are widely distributed in oceans, lakes, rivers, activated sludge, and farmland soil. The photosynthetic bacteria have the functions of fixing nitrogen, fixing carbon, producing hydrogen, desulfurizing and the like, and are used in the fields of biological bacterial manure, sewage treatment, chemical pesticide degradation and the like. In recent years, the photosynthetic bacteria can promote the growth of crops, can effectively prevent and treat crop diseases, is nontoxic to human and livestock, and has huge application prospect in the field of biological prevention and treatment. At present, 2 photosynthetic bacteria pesticide products have obtained pesticide registration certificates.

Photosynthetic bacteria belong to water ring microorganisms, have high requirements on the moisture content in the environment, and are difficult to survive for a long time when the moisture in the environment is less than 10 percent. At present, most of photosynthetic bacteria products (microbial fertilizer, water purifying agent, microbial pesticide and the like) on the market exist in a liquid form, and the form has the problems of easy pollution, loss, difficult storage, inconvenient transportation and the like of thalli, is not beneficial to the storage and the stable quality of the products, and has extremely high transportation cost. Most of the cured photosynthetic bacteria products take zeolite powder, rice hull powder or non-woven fabrics and the like as carriers, and the photosynthetic bacteria are adsorbed and fixed to form particles or blocks for aquaculture or water body purification. It has also been reported that photosynthetic bacteria are precipitated by using flocculant, the supernatant is removed, then protective agent and filler are added to form wettable powder product, and the solidification of photosynthetic bacteria by said technology is mainly implemented by firstly concentrating to remove supernatant, then using embedding agent of sodium alginate, etc. and adopting drip-injection method to embed thallus and make it into small ball or adsorb it on the carrier so as to fix thallus, effectively stabilizing free thallus and reducing loss. However, these curing methods have problems in several respects: (1) photosynthetic bacteria thalli are embedded by adopting a dripping method to prepare small balls or can not release living thalli again after being adsorbed on a carrier; (2) the drip method is usually operated by a needle cylinder or an injector, and industrial batch production is difficult to realize; (3) the thalli is concentrated to remove the supernatant, a large amount of secondary metabolites are in the supernatant in the fermentation production process of photosynthetic bacteria, the secondary metabolites contain biocontrol factors, and the disease prevention effect of the product can be obviously reduced after the removal of the biocontrol factors; (4) the water content of the product obtained by the prior art is large, generally exceeds 10 percent, the product is not beneficial to long-term normal temperature storage, and if the product meets high temperature suddenly in the process of storage or transportation, the thallus can be inactivated.

Disclosure of Invention

The technical problem to be solved by the invention is to overcome the defects of the prior art and provide the photosynthetic bacterium viable bacteria powder which can efficiently protect the activity and secondary metabolites of photosynthetic bacterium thallus, is suitable for the environment with low water content, long storage time at normal temperature and high temperature, good stability, low transportation cost and good effect of preventing and treating crop diseases, and the preparation method and the application thereof.

In order to solve the technical problems, the invention adopts the following technical scheme.

A photosynthetic bacteria viable bacteria powder is prepared by taking photosynthetic bacteria culture solution as a raw material, taking trehalose, ascorbic acid and sorbitol as freeze-drying protective agents, taking chitosan and sodium alginate as thickening agents and taking kaolin as a solid filler.

Preferably, the photosynthetic bacteria culture solution, the trehalose, the ascorbic acid, the sorbitol, the chitosan, the sodium alginate and the kaolin are in a ratio of 100mL to 0.5-1.0 g to 0.025-0.05 g to 0.05-0.1 g to 0.5-1.0 g to 1.0-1.5 g to 2.0g to 2.5g, and the concentration of the photosynthetic bacteria culture solution is 1 x 10⁹cfu/mL～9×10⁹cfu/mL。

Preferably, the photosynthetic bacteria viable bacteria powder has a water content of 2.5-3.0%, a storage temperature of 4-42 ℃ and a storage time of 1 year.

As a general technical concept, the invention also provides a preparation method of the photosynthetic bacteria live bacteria powder, which comprises the following steps:

(1) adding a freeze-drying protective agent into a photosynthetic bacteria culture solution, wherein the freeze-drying protective agent is trehalose, ascorbic acid and sorbitol, and uniformly mixing to obtain a photosynthetic bacteria liquid containing the freeze-drying protective agent;

(2) sequentially adding chitosan and sodium alginate into the photosynthetic bacteria liquid containing the freeze-drying protective agent, and uniformly mixing to make the bacteria liquid become thick;

(3) adding kaolin into the thick photosynthetic bacteria liquid, mixing uniformly, absorbing excessive water, and changing the photosynthetic bacteria liquid from thick to slurry;

(4) freeze drying the slurry photosynthetic bacteria liquid to form solid matter with water content of 2.5-3.0%, crushing and sieving to obtain live photosynthetic bacteria powder.

Preferably, in the preparation method of the photosynthetic bacteria viable bacteria powder in steps (1) to (3), the ratio of the photosynthetic bacteria culture solution, trehalose, ascorbic acid, sorbitol, chitosan, sodium alginate and kaolin is 100 mL: 0.5-1.0 g: 0.025-0.05 g: 0.05-0.1 g: 0.5-1.0 g: 1.0-1.5 g: 2.0-2.5 g.

Preferably, in the step (4), the freeze drying is vacuum freeze drying at-180 ℃ or freeze spray drying at-40 ℃.

As a general technical concept, the invention also provides application of the photosynthetic bacteria live bacteria powder or the photosynthetic bacteria live bacteria powder prepared by the preparation method in agricultural production.

Preferably, the agricultural production includes promoting crop growth and controlling crop diseases, and the crop diseases include one or more of crop nematode disease, crop virus disease and rice blast.

In the present invention, the photosynthetic bacteria include Rhodopseudomonas acidophilus (Rhodoblastus acidophilus), Rhodopseudomonas palustris (Rhodopseudomonas palustris), Rhodopseudomonas capsulata (Rhodopseudomonas capsulata), Rhodopseudomonas sphaeroides (Rhodopseudomonas sphaeroides), and Rhodooomycete sulphurophilum (Rhodovulum sulphurophilum). The photosynthetic bacteria are obtained by separation in the laboratory, are preserved and disclosed, can promote the growth of crops, and have biocontrol bacteria with better control effects on plant nematode diseases, vegetable virus diseases, rice blast and other diseases.

Compared with the prior art, the invention has the advantages that:

1. the photosynthetic bacteria culture solution is directly utilized, and the freeze-drying protective agent is adopted to protect the photosynthetic bacteria thalli and secondary metabolites in the culture solution, so that the phenomenon that the thalli cells are physiologically damaged or the structure of the secondary metabolites is changed to lose activity in the freeze-drying process is avoided; adopting a high water absorption thickening agent, forming porous hydrophilic composite gel by electrostatic attraction of anions and cations of chitosan and sodium alginate, adsorbing photosynthetic bacteria thallus and secondary metabolites, and absorbing water to make the bacteria liquid become thick; kaolin is used as a filler, so that bacteria liquid is further adsorbed, free water is reduced, the bacteria liquid is further thickened, the suspension property of the product is improved, and the low-temperature drying time and energy consumption are reduced. The product of the invention has good stability, can be stored for 14 days at a high temperature of 60 ℃, has no significant difference between the viable bacteria rate and the normal temperature, and obviously prolongs the shelf life of the product. Meanwhile, compared with a liquid microbial inoculum, the developed powder product is convenient to store and transport, and the transport cost is obviously reduced. The prepared photosynthetic bacteria microorganism powder product can be directly applied to fields by means of direct broadcasting or dissolving in water to prepare suspension for direct spraying and the like.

2. The invention solves the production pattern of long-term aqueous products of photosynthetic bacteria microbial fertilizers (pesticides), and the prepared photosynthetic bacteria viable bacteria powder contains secondary metabolites (disease-resistant factors, growth-promoting factors and the like) secreted in the culture production process of photosynthetic bacteria. The photosynthetic bacteria powder product prepared by the invention is not easy to infect infectious microbes, has good bacteria quality and good stability, can be widely applied to promoting crop growth or preventing and treating diseases in agricultural production as microbial fertilizer or microbial pesticide, and can be directly applied by broadcasting or spraying with water. The photosynthetic bacteria powder product produced by the invention has the advantages of convenient storage, long shelf life, convenient transportation, simple and easy packaging and easy implementation.

Drawings

FIG. 1 shows the viable bacteria detection results of the photosynthetic bacteria viable bacteria powder containing different freeze-drying protective agents in example 1 of the present invention.

FIG. 2 is a graph showing the survival of the photosynthetic bacteria after high temperature treatment in example 1 of the present invention by a plate assay.

FIG. 3 shows the survival rates of viable bacteria powder of photosynthetic bacteria at different storage temperatures and times in example 1 of the present invention.

FIG. 4 is a result of a potting experiment for controlling tomato root knot nematode disease with live photosynthetic bacteria powder in example 2 of the present invention.

Detailed Description

The invention is further described below with reference to the drawings and specific preferred embodiments of the description, without thereby limiting the scope of protection of the invention. Unless otherwise specified, materials and instruments used in the following examples are commercially available.

Example 1:

the invention relates to a photosynthetic bacteria live bacteria powder, which is prepared by taking photosynthetic bacteria culture solution as a raw material, taking trehalose, ascorbic acid and sorbitol as freeze drying protective agents, taking chitosan and sodium alginate as thickening agents and taking kaolin as solid fillers, wherein the water content is 2.5-3.0%, the storage temperature is 4-42 ℃, and the storage time can be up to 1 year.

The photosynthetic bacteria adopted in the embodiment are biocontrol bacteria with disease prevention and growth promotion functions, and comprise: the strain is a strain separated from key laboratories for controlling diseases and insect pests of horticultural crops in Hunan province, and is preserved in China center for type culture Collection, and the preservation numbers are respectively as follows: CTCC No: m206124, CTCC No: m2012369, CTCC No: m2014525, CTCC No: m2012518, the publication numbers related to patent documents are respectively: CN100546482, CN103525729, CN105794853, and CN 103224904.

The preparation method of the living photosynthetic bacteria powder of the embodiment comprises the following steps:

(1) adding freeze-drying protective agents trehalose, ascorbic acid and sorbitol into the photosynthetic bacteria culture solution, and uniformly mixing to obtain the photosynthetic bacteria culture solution containing the freeze-drying protective agents. The freeze-drying protective agent can protect the photosynthetic bacteria thallus and the secondary metabolite structure thereof from being damaged in the low-temperature freeze-drying process, and the photosynthetic bacteria thallus can keep activity under low water content.

(2) And (2) sequentially adding the super absorbent thickener chitosan and sodium alginate into the photosynthetic bacteria liquid containing the freeze-drying protective agent obtained in the step (1), and uniformly mixing to make the mixture become thick. The thickening agent is added in the step for the purpose of reducing water in the bacterial liquid on one hand and adsorbing and protecting the thalli on the other hand.

(3) And (3) adding kaolin serving as a solid filler into the thick photosynthetic bacteria liquid obtained in the step (2), and uniformly mixing to absorb excessive water to form slurry photosynthetic bacteria liquid.

(4) And (3) putting the slurry-like photosynthetic bacteria liquid obtained in the step (3) into a vacuum low-temperature dryer at the temperature of minus 180 ℃ for vacuum low-temperature freeze drying for 6 to 8 hours to obtain solid matters, then crushing the solid matters by using a crusher, and sieving the crushed solid matters by using a 100-mesh sieve to obtain photosynthetic bacteria living bacteria powder, or directly performing freeze spray drying at the temperature of minus 40 ℃ to obtain photosynthetic bacteria living bacteria powder. And packaging the powder according to the dosage to obtain a powder product applied to production.

In this example, the ratio of the photosynthetic bacteria culture fluid, trehalose, ascorbic acid, sorbitol, chitosan, sodium alginate, and kaolin is 100 mL: 0.5 g: 0.025 g: 0.05 g: 0.5 g: 1 g: 2 g.

In this embodiment, the photosynthetic bacteria culture solution is prepared by the following method, but is not limited thereto.

(1) Activating strains: culturing photosynthetic bacteria (such as one of Acidophilic Flavobacterium sp) stored at ultralow temperature by plate culture method until red colony appears. The plate culture method preferably adopts a double-layer MSYN solid culture medium for culture under the conditions of pH value of 7.0-7.2, temperature of 30-35 ℃ and illumination condition of 2000-3000 Lx. The MSYN solid culture medium comprises the following components in percentage by weight: (NH)₄)₂SO₄ 0.1wt％、MgSO₄ 0.02wt％、NaHCO₃ 0.5wt％、K₂HPO₄0.05 wt%, NaCl 0.02 wt%, yeast extract 0.15 wt%, agar 1.5 wt%, and water in balance, and the pH is 7.0.

(2) Seed culture: inoculating the red single colony cultured in the step (1) into a serum bottle, and culturing the red single colony to a logarithmic phase by using a strain seed culture medium such as acidophilic beralid. The seed culture medium is MSYN liquid culture medium, the pH value is 7.0-7.2, the culture temperature is 30-35 ℃, and the illumination condition is 2000-3000 Lx. The MSYN liquid culture medium comprises the following components: (NH)₄)₂SO₄ 0.1wt％、MgSO₄0.02wt％、NaHCO₃ 0.5wt％、K₂HPO₄0.05 wt%, NaCl 0.02 wt% and yeast extract 0.15 wt%, pH 7.0.

(3) Production and culture: inoculating the bacterial liquid obtained after the culture in the step (2) into a production bottle according to the inoculation amount which is not less than 1-5% of the total volume of the production culture medium of strains such as acidophilic berra red bacteria and the like, and culturing until the concentration is (1-9) multiplied by 10⁹cfu/mL, and obtaining the photosynthetic bacteria culture solution for powder preparation. The production culture medium is MSYN liquid culture medium, the pH value is 7.0-7.2, the culture temperature is 30-35 ℃, and the illumination condition is 2000-3000 Lx.

In the present invention, the selection of the lyoprotectant is critical to the survival of the photosynthetic bacteria. The freeze-drying protective agent is obtained by screening a large number of experiments, and the examples and the comparisons are as follows:

research shows that the viable bacteria yield of the prepared bacterial powder is respectively between 25 and 55 percent by using skim milk powder, glucan, glycerol, sodium ascorbate and the like as protective agents in the freeze drying of bacillus. The applicant studied using sucrose, trehalose, ascorbic acid, sorbitol, skim milk powder, glycerol, etc. as cell freeze-drying protectants, respectively, and used no freeze-drying protectant as a control. Different freeze-drying protective agents are respectively added into 100mL of photosynthetic bacteria liquid, and the type and the concentration are shown in Table 1.

TABLE 1 Freeze-drying protection agents and their amounts

Photosynthetic bacteria liquid containing different freeze-drying protective agents is operated according to the preparation steps of the photosynthetic bacteria viable bacteria powder of the embodiment, viable bacteria detection is carried out, and the result is shown in fig. 1. As is clear from FIG. 1, the combination of trehalose, sodium ascorbate and sorbitol gave the best protective effect on the photosynthetic bacteria cells and a high viable cell yield. On the basis, an orthogonal test is carried out by utilizing trehalose, sodium ascorbate and sorbitol, and the result shows that when 0.5g to 1.0g of trehalose, 0.025g to 0.05g of ascorbic acid and 0.05g to 0.1g of sorbitol are added into 100mL of photosynthetic bacteria culture solution, the viable bacteria yield reaches more than 95 percent.

In the invention, the thickening agent is added in the preparation process of the photosynthetic bacteria viable bacteria powder, so that the water in the product can be reduced, the bacteria liquid becomes viscous, and the adsorption and embedding effects on the thalli and secondary metabolites are realized, thereby reducing the energy consumption in the freeze drying process and maintaining the activity of the thalli and the secondary metabolites. Sodium alginate, chitosan, carboxymethyl starch and carboxymethyl cellulose are selected as thickening agents, the water absorption thickening capacity of the thickening agents is observed through a single-factor and orthogonal test, and proper thickening agents are screened. The test result shows that: when 0.5g to 1.0g of chitosan and 1.0g to 1.5g of sodium alginate are sequentially added into 100mL of photosynthetic bacteria culture solution, the thickening and water absorption effects are the best. Meanwhile, 2.0 g-2.5 g of kaolin is added as a filling material on the basis, so that the content of free water in the bacterial liquid is reduced, the subsequent freeze drying is facilitated, the drying time and the energy consumption are reduced, and the suspension property of the product is improved.

Product viable bacteria detection

For microbial preparations, the number of viable bacteria and shelf life are one of the important criteria for measuring products, and therefore, the detection of bacterial activity of products with different storage times is extremely important for photosynthetic bacterial powder products. The bacteria activity detection steps of the photosynthetic bacteria viable bacteria powder of the embodiment are as follows:

(1) the photosynthetic bacteria viable bacteria powder prepared in the embodiment is divided into two groups (non-high-temperature treated group and high-temperature treated group) after being subpackaged, one group is respectively placed in a constant temperature box at 4 ℃ and normal temperature for storage, the other group is placed in a constant temperature box at 60 ℃ for 14 days, then is respectively placed in a constant temperature box at 4 ℃ and normal temperature for storage, and then is respectively taken out at 21 days, 60 days, 90 days, 6 months and 1 year for viable bacteria number detection.

(2) Weighing 0.02g of photosynthetic bacteria viable bacteria powder treated at high temperature of 60 ℃, adding 2mL of sterilized water, mixing uniformly to obtain suspension, and sequentially diluting to 10 by using MSYN liquid culture medium^-2、10^-3、10^-4So that the concentrations are about 1X 10 respectively⁷cfu/mL、1×10⁶cfu/mL and 1X 10⁵cfu/mL, using 1000-fold bacterial liquid diluted by photosynthetic bacteria culture solution as a control. And taking 100 mu L of diluted bacterium liquid, coating a flat plate, performing double-layer culture on the photosynthetic bacteria for 3-7d by using MSYN solid culture medium, and observing the growth condition of colonies. The experimental results show that, starting from 3d, the treatment with different dilution concentrations started to appear a few red colonies, and the colonies of the control treatment grew faster. After 7 days of growth, all treatments developed a large number of colonies, which grew progressively faster and the colonies were more red in color than the control. Shows the bacterial activity of the prepared powder productPreferably, although the growth in the early stage is slower than that in the liquid microbial inoculum, the recovery is fast obtained, and the result is shown in FIG. 2.

(3) Weighing 0.02g of photosynthetic bacteria viable powder with different storage temperatures and time, adding 2mL of sterilized water, mixing to obtain suspension, diluting 1000 times with MSYN liquid culture medium to make photosynthetic bacteria concentration about 1 × 10⁶cfu/mL, respectively taking 1mL of the diluent, respectively filling the diluent into a 15mL glass centrifuge tube containing MSYN liquid culture medium, sealing, and placing the centrifuge tube in an incubator at the temperature of 30-35 ℃ and under the illumination condition of 2000-3000 Lx for culturing for 3-7 days to change the liquid into red. Inoculating photosynthetic bacteria culture solution (diluted 1000 times to make inoculation concentration about 1 × 10)⁶cfu/mL) as a control. OD Using microplate reader₆₀₀The bacterial liquid concentration is measured and calculated, and the survival rate of the powder bacteria is calculated by comparing with the control, and the result is shown in figure 3. As can be seen from FIG. 3, the photosynthetic bacteria viable bacteria powder prepared by the invention has better activity of photosynthetic bacteria, and compared with the powder which is not processed at high temperature, the powder processed at 60 ℃ has no significant difference in bacterial activity. In addition, the detection result shows that the bacterial activity in the product is reduced with the prolonging of the storage time, but the reduction amplitude is not large, and the viable bacteria rate in the powder is reduced by 18.7-20.1% compared with 21d after the product is stored for one year. Compared with photosynthetic bacteria culture solution, the active bacteria still keep above 70%.

Example 2

The invention relates to an application of photosynthetic bacteria live bacteria powder in preventing and treating agricultural crop diseases, in particular to a test for preventing and treating tomato root-knot nematode disease by using developed acidophilic berra red bacteria powder products in greenhouse potting, which comprises the following steps: the test is designed with 3 treatments, powder of 0.5 g/pot, 1.0 g/pot and 2.0 g/pot is scattered around the tomato roots, the soil is turned over and covered, meanwhile, the test is designed with 1000 times of 1.8 percent avermectin emulsifiable solution and clear water as control treatments, and each treatment is carried out on 10 tomatoes. And (3) when 3-4 leaf-aged tomatoes are transplanted to survive, processing, and inoculating the meloidogyne incognita on the next day, wherein the inoculation amount is 500 second-instar larvae per pot. The root knot situation of the tomatoes is investigated after 60 days, the test result is shown in figure 4, the control effect is increased along with the increase of the dosage of the powder, when the powder product is applied at 1.0 g/pot, the control effect can reach 63.16%, and the control effect difference of the powder product and 2.0 g/plant treatment and abamectin contrast treatment on the tomato root knot nematode disease is not obvious, so that the photosynthetic bacterium viable bacteria powder has great application potential in the prevention and control of the crop nematode disease, can be used as a substitute product of abamectin, and can reduce the generation of drug resistance of the nematode to the abamectin.

The foregoing is merely a preferred embodiment of the invention and is not intended to limit the invention in any manner. Although the present invention has been described with reference to the preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make many possible variations and modifications to the disclosed embodiments, or equivalent modifications, without departing from the spirit and scope of the invention, using the methods and techniques disclosed above. Therefore, any simple modification, equivalent replacement, equivalent change and modification made to the above embodiments according to the technical essence of the present invention are still within the scope of the protection of the technical solution of the present invention.