CN109762766B

CN109762766B - Bacterium capable of adsorbing heavy metals, dissolving phosphorus and benefiting plants and application thereof

Info

Publication number: CN109762766B
Application number: CN201910112113.3A
Authority: CN
Inventors: 章朦玥; 张怡轩
Original assignee: Shenyang Pharmaceutical University
Current assignee: Shenyang Pharmaceutical University
Priority date: 2019-02-13
Filing date: 2019-02-13
Publication date: 2022-06-14
Anticipated expiration: 2039-02-13
Also published as: CN109762766A

Abstract

The invention relates to a probiotic bacterium (Edaphovirga sp) and application thereof, in particular to a probiotic bacterium and an effect thereof on adsorbing heavy metals, dissolving phosphorus and benefiting life, belonging to the field of development and utilization of microbial resources. The strain is preserved in the common microorganism center of China Committee for culture Collection of microorganisms, and the preservation number is CGMCC No. 15748. The strain has strong heavy metal adsorption and phosphate-solubilizing effects, and effects of promoting plant growth and plant seed germination. The invention uses the strain suspension or the strain fermentation liquor extract or the solid microbial inoculum containing the strain to carry out root irrigation or broadcast application treatment on the plant. Can be used independently or mixed with organic fertilizer to prepare bacterial fertilizer, which lays a solid foundation for high yield, stable yield and high quality of the planting industry and has very important significance for developing the production of green and pollution-free agriculture.

Description

Bacterium capable of adsorbing heavy metals, dissolving phosphorus and benefiting plants and application thereof

Technical Field

The invention belongs to the field of development and utilization of microbial resources, and relates to a bacterium (Edaphovirga sp) capable of adsorbing heavy metals, dissolving phosphorus and benefiting plants and application thereof, in particular to a probiotic bacterium and an effect of adsorbing heavy metals, dissolving phosphorus and benefiting life thereof.

Background

With the development of social economy and the gradual enhancement of human activities, the problem of soil and water pollution is more and more serious because high-content heavy metals are released to the natural environment by mineral resource development, electroplating, steel manufacturing, tanning, chemical processing, application of chemical fertilizers and the like. According to statistics, the area of the soil polluted by heavy metal in China reaches ten thousand hectares and occupies 1/6 of the total cultivated land area in China by 2016. At present, heavy metal elements with excessive content in soil polluted by heavy metals in China mainly comprise chromium (Cr), cadmium (Cd), lead (Pb), mercury (Hg) and the like, and the heavy metal elements are accumulated through a food chain to harm human health. When excessive Cd is ingested by a human body, the decrease of bone density and fracture can be caused. When Pb enters a human body, the Pb causes the reduction of the immunity of the human body, and when the Pb is accumulated to a certain amount, symptoms such as headache, memory deterioration, abdominal pain and the like can be caused, thereby seriously threatening the human bodyIt is similar to health. Therefore, remediation of soil heavy metal pollution is imperative. The heavy metal pollutants have extremely poor mobility in soil, long retention time and biological non-destructiveness, so that the method for repairing the heavy metal pollutants by finding an eco-friendly method is very important. At present, the main technical means for repairing the heavy metal contaminated soil comprise physical, chemical and biological repair. The first two methods have good repairing effect in a short time, but have the problems of large engineering quantity, high cost and the like, and are easy to cause secondary pollution to soil. In recent years, the heavy metal bioremediation technology gradually becomes a research hotspot at home and abroad, and the plant and microorganism combined remediation technology which is characterized by being green, environment-friendly and cheap is concerned. The microbial remediation method utilizes the adsorption, transformation and metabolism of microorganisms on heavy metals, can reduce the toxicity of the heavy metals in the soil, can improve the microenvironment of the root systems of plant crops, thereby reducing the remediation cost, is not easy to cause secondary pollution, can treat underground water and soil simultaneously, is small in time and space limitation, and is an important means for remedying the heavy metal contaminated soil. Studies of the ursofen and the like find that hydroxyl, carboxyl, C-O-C and other groups in the Extracellular Polymeric Substance (EPS) of the aspergillus fumigatus are similar to Pb ²⁺The primary group of binding. Manasi et al utilize a strain of halomonas to treat Cd-rich in electronic industry²⁺And (4) waste water.

Phosphorus is one of three essential nutrients for the growth of higher plants, and is an indispensable element for the participants of various metabolic activities in the growth and development process of plants and the formation of nuclear protein, lecithin and the like. 95% of phosphorus in soil exists in an organic or inorganic phosphide state, the water solubility is low, the phosphorus is difficult to be directly absorbed and utilized by plants, and only a small proportion of fast-acting phosphorus can be directly utilized by the plants, so that the phosphorus in the world is lack. In agricultural production, a large amount of phosphate fertilizer is applied to increase the supply of phosphorus in soil, but the phosphate fertilizer is very easy to be mixed with Ca in the soil²⁺、Al³⁺、Fe²⁺And Fe³⁺The chelation forms insoluble phosphate, the utilization efficiency of phosphate fertilizer is only 5% -25%, and the excessive use of the fertilizer can damage the soil structure and pollute the environment. Therefore, the decomposition and aggregation of immobilized inefficient phosphorus in soil were investigatedThe release has important significance for improving the content of soluble phosphorus in the soil and adjusting the soil fertility. The phosphate solubilizing microorganism can convert phosphorus which is difficult to be absorbed by plants into a usable state, and has obvious effects on improving the content of available phosphorus in soil, improving the utilization rate of phosphate fertilizer, promoting the growth of crops and the like. 1 strain P83 Penicillium decumbens capable of dissolving insoluble phosphorus is screened by Shicheng et al, the effective phosphorus level of soil can be obviously improved, and the method has obvious effects on corn growth and yield increase. Therefore, the phosphate-solubilizing microorganism resource has wider application prospect in the development process of future sustainable agriculture and forestry.

The prevention and control of plant diseases in modern agriculture excessively depends on the use of chemical pesticides, so that the agricultural pesticide has a long-term destructive effect on the ecological environment, and causes the problems of quality reduction of agricultural products, over-standard pesticide residue, drug resistance of pathogenic bacteria and the like. The resistance of plants to diseases and other stresses is related to the activity change of a plurality of enzymes such as Phenylalanine Ammonia Lyase (PAL), superoxide dismutase (SOD), Peroxidase (POD) and the like, and biocontrol bacteria can induce the activity change of disease-resistant related defense enzymes of the plants and enhance the disease-resistant capability. Superoxide dismutase (SOD) plays an important role in active oxygen metabolism, can prevent superoxide radicals from oxidizing a biological membrane system, and the activity of the SOD is an important mark for the anti-aging capability of plant cells. Peroxidase (POD) not only participates in polymerization reaction of lignin, but also is an important endogenous active oxygen scavenger in cells, and can catalyze H₂O₂Decomposition into H₂O and O₂. The Linchenqiang and the like find that the Bacillus subtilis CS16 fermentation liquor and the supernatant liquor treated banana seedlings can induce the activity change of the defense enzymes such as SOD, PAL, POD and the like in banana leaves. Therefore, the biological method for improving the activity of the plant defense enzyme system to improve the stress resistance of the plant and the reduction of the application of chemical pesticides have very important significance for developing the production of green pollution-free agriculture.

Disclosure of Invention

The invention aims to: provides a probiotic bacterial strain (Edaphovirga sp) separated and screened from Chinese soil, which has the functions of adsorbing heavy metals, dissolving phosphorus and benefiting plant seeds and plants. Can be used as a biological fertilizer to achieve the purpose of improving the yield and the quality, and has the characteristics of low cost, no pollution to the environment and safety to people and livestock.

The probiotic bacteria are obtained by the following method:

taking rhizosphere soil of Codonopsis pilosula in Xinjiang, removing stones from the soil sample, weighing 5g, placing into a triangular flask containing 45mL of sterile water, and oscillating for 20min, namely 10^-1The soil suspension of (a); diluting to 10 degrees in stages^-2、10^-3、10^-4、10^-5Then, each diluent is taken and coated on a separation plate, inverted and cultured for 1-5 days at 26 ℃. Culture observation, single colony growth after transfer to LB medium culture, has obtained strains (Edaphovirga sp.).

The invention also provides the effects of the probiotic bacteria in adsorbing heavy metals, dissolving phosphorus and benefiting plant seeds and plants.

The invention can use bacterial strain suspension or bacterial strain fermentation liquor extract of probiotic bacteria (Edaphovirga sp) or solid microbial inoculum containing the bacterial strain to irrigate roots or broadcast the plants.

The preparation method of the strain suspension comprises the following steps: taking out the strain storage tube, recovering the strain storage tube by using an LB solid culture medium, culturing the strain storage tube at 20-37 ℃ for 24-48 hours, preparing the activated strain into a bacterial suspension by using distilled water, and measuring the concentration of the bacterial suspension by using an ultraviolet spectrophotometer under the wavelength of 600nm, wherein the concentration of the bacterial suspension is as follows: 0.1-0.8. The LB solid culture medium has the formula: peptone 1-5%, yeast extract 0.1-5%, NaCl 0.1-3%, agar 1.5-2%, and water 1000 ml.

Secondly, the preparation method of the strain fermentation liquor or the strain fermentation liquor extracting solution comprises the following steps: taking out the strain storage tube, recovering the strain storage tube by using an LB solid culture medium, and culturing the strain storage tube for 24 to 48 hours at the temperature of between 20 and 37 ℃. Single colonies were picked from the plates and inoculated into 50ml LB medium and shake-cultured in an incubator at 20-37 ℃ for 24-72 hours. The seeds are inoculated into LB culture medium with the inoculation amount of 1-10% for expanding culture for 24-72 hours. The concentration of the bacterial liquid is greater than OD₆₀₀Finishing fermentation, aseptically packaging to obtain liquid product, or freeze drying to obtain powderAnd (5) finishing. And extracting the obtained strain fermentation liquor by using equal volume of ethyl acetate, and collecting concentrated extract liquor to obtain a strain fermentation liquor extracting solution for later use.

Thirdly, the solid microbial inoculum is prepared by the following method: inoculating the obtained strain fermentation liquor into a solid microbial inoculum culture medium, culturing at 20-40 ℃, stirring under aseptic conditions after culturing for 1-3d, and continuously culturing for 1-3d after stirring to obtain the solid microbial inoculum. The formula of the solid microbial inoculum culture medium comprises, by g/ml, 20-50% of wheat bran, 10-30% of corn flour, 1-10% of soybean flour, 0.1-1% of potassium nitrate, 0.1-1% of dipotassium phosphate, 0.4-0.7% of sodium chloride, 1-10% of calcium carbonate and 200ml of distilled water.

The microbial inoculum prepared in the first step and the second step can be diluted by 10-10000 times for use, or the microbial inoculum prepared in the third step is directly broadcast or mixed with other organic fertilizers for use.

The probiotic bacteria (Edaphovirga sp.) of the invention are preserved in the general microbiological center of China Committee for culture Collection of microorganisms, and the address is as follows: the microbial research institute of the national academy of sciences No. 3, Xilu No.1, Beijing, Chaoyang, Beijing, with the preservation number: CGMCC No.15748, and the preservation date is 09 months 05 and 2018.

Drawings

FIG. 1 shows the adsorption rate of strain Edaphovirga sp.No.15748 on Pb and Cd;

FIG. 2 is a phosphorus content standard curve drawn by Mo-Sb colorimetry at a wavelength of 700 nm;

FIG. 3 shows the phosphate solubilizing ability of the strain Edaphovirga sp.No.15748 on liquid medium.

Detailed Description

The following detailed description is to be read in connection with specific embodiments, but it should be understood that the scope of the invention is not limited to the specific embodiments. The experimental procedures used in the following examples are all conventional procedures unless otherwise specified. Materials, reagents and the like used in the following examples are commercially available unless otherwise specified.

Example 1 Strain (Edaphovirga sp.) CGMCC No.15748 heavy Metal adsorption

Heavy metal tolerance test: the strain (Edaphovirga sp.) CGMCC No.15748 reaches the final concentration of 200mg/L, 400mg/L and 800mg/L in solid LB when the concentration of heavy metals (lead and cadmium) reaches to carry out a plate tolerance experiment.

Testing the heavy metal adsorption capacity: inoculating the seed solution into a fermentation solution with the heavy metal concentration of 60mg/L according to the proportion of 2%, fermenting for 48h at the temperature of 26-35 ℃ at the speed of 120-200r/min, taking a culture medium without inoculating bacteria as a contrast, carrying out three groups of parallel operations, centrifuging the 24h and 48h fermentation solution, then adding 3ml of supernatant, adding 3ml of concentrated nitric acid, and adding water to dilute to 45ml, thus obtaining the sample to be detected. The total metal ion concentration remaining in the fermentation broth was determined by ICP-MS (inductively coupled plasma mass spectrometry).

The result is shown in figure 1, the strain (Edaphovirga sp.) CGMCC No.15748 has the advantages that the Pb adsorption rate reaches 40 +/-1.63 percent, the Cd adsorption rate reaches 37.5 +/-1.2 percent, the Pb adsorption rate reaches 70 +/-1.22 percent and the Cd adsorption rate reaches 67.5 +/-2.04 percent at 24 hours, and the strain shows strong heavy metal adsorption capacity.

Example 2 Strain (Edaphovirga sp.) CGMCC No.15748 phosphate solubilizing action

Preparation of PKO medium: 0.5% of tricalcium phosphate, 1-5% of sucrose, 0.1-1% of ammonium sulfate, 0.01-0.1% of yeast powder, 0.01-0.1% of sodium chloride, 0.01% of anhydrous magnesium sulfate, 0.02% of potassium chloride, 3ml of 1% manganese sulfate, 3ml of 1% ferrous sulfate, 18g of agar and 1000ml of distilled water, wherein the pH value is 7, and the mixture is sterilized at 121 ℃ for 30 min.

A phosphorus ring dissolving method: inoculating a strain (Edaphovirga sp.) with CGMCC No.15748 point on a PKO culture medium, placing the strain in an incubator at 26-35 ℃ for culturing for 3-4d, observing a transparent ring, and primarily determining that the strain has the phosphate-solubilizing capability.

Molybdenum-antimony colorimetric resistance: bacterial strain (Edaphovirga sp.) CGMCC No.15748 is fermented for 24h at the temperature of 26-35 ℃ by using 50ml of liquid LB culture medium at 120-. Respectively and accurately absorb 5mg/L of phosphorus (K) ₂HPO ₄) 0, 2, 4, 6, 8 and 10ml of standard solution is put into a 50ml volumetric flask, and simultaneously the sample solution used for the chromogenic assay is addedAdding 2-3 drops of dinitrophenol indicator into blank solution with the same volume, adjusting the solution to be just yellowish by using 100g/L sodium carbonate solution, accurately adding 5ml of molybdenum-antimony color-resisting reagent, shaking up, adding water to constant volume to obtain standard solution with phosphorus (P) content of 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0mg/L respectively. Shaking, standing at room temperature for 30 min. The absorbance was measured at a wavelength of 700nm, and a standard curve was plotted with the absorbance as the ordinate and the phosphorus concentration (mg/L) as the abscissa, with the results shown in FIG. 2. Transferring a proper amount of liquid to be measured into a 50ml volumetric flask, diluting with a proper amount of water, adding 1-2 drops of a dinitrophenol indicator, adjusting the solution to be slightly yellow by using 100g/L sodium carbonate solution or 50ml/L sulfuric acid solution, accurately adding 5ml of molybdenum-antimony anti-color-developing agent, shaking up, adding water to a constant volume, and standing at room temperature for 30 min. And (3) in an ultraviolet spectrophotometer, adjusting the wavelength of the ultraviolet spectrophotometer to be zero by taking a blank culture medium which is not connected with thalli as a reference solution, measuring the absorbance of the ultraviolet spectrophotometer, and calculating the corresponding phosphorus content according to a standard curve.

As shown in FIG. 3, the effective phosphorus content of the strain (Edaphovirga sp.) CGMCC No.15748 in the culture solution of the inoculation treatment reaches 525.33 +/-12.26 mg/L, is obviously higher than CK, and shows strong phosphate-solubilizing effect.

Example 3 promotion of seed Germination of Panax notoginseng with Strain (Edaphovirga sp.) CGMCC No.15748

Cleaning Notoginseng radix seed, rinsing with sterile water for 3 times under aseptic condition, and drying surface with sterile absorbent paper. The strain was prepared to 10 using sterile water⁷、10⁵、10³、10¹cfu/ml of bacterial suspension, distilled water as Control (CK), ready for use. Each group is three times, each time 30 seeds are repeated, and each group is soaked for 3-5h by using 10ml of bacterial suspension diluent or distilled water. Filtering with a screen to obtain seeds, performing moisture-preserving culture at 20-25 deg.C for 16 days, counting the germination rate of Notoginseng radix seeds, and measuring root activity, bud length, diameter and freshness, the results are shown in tables 1 and 3. The root activity determination method is triphenyltetrazolium chloride (TTC) method, and refers to Zhangyilian 'plant physiology experiment guidance third edition'.

The strain (Edaphovirga sp.) No.15748 was fermented with 50ml of liquid LB medium at 26-35 ℃ for 24h at 120-Inoculating into LB culture medium according to 1% inoculum size, fermenting for 2 days under the same conditions to obtain OD₆₀₀The fermentation broth was centrifuged at 0.3 to obtain a supernatant, which was diluted 10%²、10⁴And 10⁶The results of treating the seeds of panax notoginseng twice as the test procedures are shown in tables 2 and 4.

Through the measurement indexes, the results of significant difference analysis by using Graphpad software are shown in tables 1 and 2, and the germination rates of the panax notoginseng seeds treated by the Edaphovirga sp.No.15748 strain are higher than those of a control group and have significant differences, which indicates that the strain has a promoting effect on the germination of the panax notoginseng seeds. And as shown in tables 3 and 4, the bacterial suspension and the fermentation liquor of the bacterial strain can obviously improve the biomass and the root activity of pseudo-ginseng seeds, play a role in promoting the nutrient absorption of pseudo-ginseng and have a role in promoting the growth of pseudo-ginseng seeds.

TABLE 1 influence of the suspension of the strain Edaphovirga sp.No.15748 on the germination (%) of seeds of Panax notoginseng

Note: p < 0.01; p <0.001.

TABLE 2 influence of the fermentation broth of the strain Edaphovirga sp.No.15748 on the germination (%) of seeds of Panax notoginseng

Note: p < 0.05; p < 0.01;

TABLE 3 promotion of seed germination of Panax notoginseng with suspension of strain Edaphovirga sp.No.15748

Note: p < 0.05; p < 0.01; p <0.001.

TABLE 4 promoting effect of strain Edaphovirga sp.No.15748 fermentation broth on seed germination of Panax notoginseng

Note: p < 0.05; p <0.001.

Example 4 Strain (Edaphovirga sp.) CGMCC No.15748 improves the activity of the root system enzyme of panax notoginseng plant

The strain (Edaphovirga sp.) CGMCC No.15748 solid microbial inoculum is used for treating pseudo-ginseng plants, a sterilized solid microbial inoculum culture medium without the strain is used as a control group (CK), samples are respectively taken on days 3, 6, 9, 12, 18 and 30 after microbial inoculum treatment, representative whole plants are selected for each group of treatment, and each 3 groups are repeated. Repeatedly washing the root, and timely measuring various root indexes after cleaning. The root activity is measured by a TTC method; the activity of superoxide dismutase (SOD) is measured by a Nitrogen Blue Tetrazolium (NBT) method, and the unit of enzyme activity is that NBT photochemical reduction is inhibited by 50 percent; peroxidase (POD) activity was measured by guaiacol method with a change of 0.01 to 1 peroxidase activity unit per min.

Results are shown in tables 5, 6 and 7, compared with a control group, the root activity of the panax notoginseng plant can be obviously improved after the panax notoginseng plant is treated by the bacterial strain solid fungicide, and the panax notoginseng plant can absorb nutrition to metabolize; can obviously improve the activity of defense enzymes SOD and POD, and can obviously improve the self defense capability of the plant.

TABLE 5 enhancement of root vigor [ μ g/(g.h) ] of Panax notoginseng plants by Edaphovirga sp.CGMCC No.15748 bacterial agents

Note: p < 0.05; p <0.001.

TABLE 6 enhancement of SOD activity (U/g) in Panax notoginseng plants by Edaphovirga sp.No.15748 inoculum

Note: p < 0.05; p <0.001.

TABLE 7 enhancement of POD activity (U/g) in Panax notoginseng plants by Edaphovirga sp.No.15748 bacterial agents

Note: p <0.001.

Example 5 probiotic action of the Strain (Edaphovirga sp.) CGMCC No.15748 on plant seeds

The test method is the same as the test of the influence of the bacterial suspension of Edaphovirga sp.No.15748 strain in the example 3 on the germination of the pseudo-ginseng seeds, the pseudo-ginseng seeds are subjected to moisture preservation and culture for 1 to 5 days at the temperature of between 20 and 25 ℃, and the root activity, the root SOD activity and the POD activity of the seeds of cucumbers, corns and lettuce are measured.

The results are shown in tables 8, 9 and 10, and the root activity, SOD activity and POD activity of the seeds treated by the Edaphovirga sp.No.15748 bacterial suspension are all higher than those of the control group, which indicates that the bacterial suspension has promotion effect on the germination of the plant seeds.

TABLE 8 enhancement of plant radicular viability [ μ g/(g.h) ] by Edaphovirga sp.No.15748 suspensions

Note: p <0.001.

TABLE 9 enhancement of plant seed SOD activity (U/g) by Edaphovirga sp.No.15748 bacterial suspension

Note: p < 0.05; p < 0.01; p <0.001.

TABLE 10 enhancement of plant seed POD activity (U/g) by suspension of Edaphovirga sp.No.15748

Note: p < 0.05; p < 0.01; p <0.001.

Sequence listing

<110> Shenyang university of pharmacy

<120> a bacterium capable of adsorbing heavy metals, dissolving phosphorus and benefiting plant life and application thereof

<160> 1

<170> SIPOSequenceListing 1.0

<210> 1

<211> 1564

<212> DNA

<213> Edaphovirga sp.

<400> 1

gctgccttag agtttgatcc tggctcagat tgaacgctgg cggcaggcct aacacatgca 60

agtcgggcgg tagcacgggg gagcttgctc cctgggtgac gagcggcgga cgggtgagta 120

atgtctggga aactgcctga tggaggggga taactactgg aaacggtagc taataccgca 180

tgacctcgca agagcaaagt gggggacctt agggcctcac gccatcggat gtgcccagat 240

gggattagct agtaggtggg gtaatggctc acctaggcga cgatccctag ctggtctgag 300

aggatgacca gccacactgg aactgagaca cggtccagac tcctacggga ggcagcagtg 360

gggaatattg cacaatgggc gcaagcctga tgcagccatg ccgcgtgtgt gaagaaggcc 420

ttcgggttgt aaagcacttt cagcgaggag gaaggcactg ttcctaatag ggatggtgat 480

tgacgttact cgcagaagaa gcaccggcta actccgtgcc agcagccgcg gtaatacgga 540

gggtgcaagc gttaatcgga attactgggc gtaaagcgca cgcaggcggt caattaagtt 600

ggatgtgaaa tccccgggct taacctggga actgcattca aaactgattg gctagagtct 660

tgtagagggg ggtagaattc caggtgtagc ggtgaaatgc gtagagatct ggaggaatac 720

cggtggcgaa ggcggccccc tggacaaaga ctgacgctca ggtgcgaaag cgtggggagc 780

aaacaggatt agataccctg gtagtccacg ctgtaaacga tgtcgacttg gaggttgtgg 840

ccttgagccg tggcttccgg agctaacgcg ttaagtcgac cgcctgggga gtacggccgc 900

aaggttaaaa ctcaaatgaa ttgacggggg cccgcacaag cggtggagca tgtggtttaa 960

ttcgatgcaa cgcgaagaac cttacctact cttgacatcc acgggatttg gcagagatgc 1020

cttagtgcct tcgggaaccg tgagacaggt gctgcatggc tgtcgtcagc tcgtgttgtg 1080

aaatgttggg ttaagtcccg caacgagcgc aacccttatc ctttgttgcc agcgcgtaat 1140

ggcgggaact caaaggagac tgccggtgat aaaccggagg aaggtgggga tgacgtcaag 1200

tcatcatggc ccttacgagt agggctacac acgtgctaca atggcatata caaagagaag 1260

caaactcgcg agagccagcg gacctcataa agtatgtcgt agtccggatt ggagtctgca 1320

actcgactcc atgaagtcgg aatcgctagt aatcgtggat cagaatgcca cggtgaatac 1380

gttcccgggc cttgtacaca ccgcccgtca caccatggga gtgggttgca aaagaagtag 1440

gtagcttaac cttcgggagg gcgcttacca ctttgtgatt catgactggg gtgaagtcgt 1500

aacaaggtaa ccgtagggga acctgcggct ggatcacctc ctaagggcag ctcaatcgcc 1560

ctat 1564

Claims

1. A bacterium (Edaphovirga sp.) having the deposit number: CGMCC No. 15748.

2. Use of the bacterium of claim 1 (Edaphovirga sp) for adsorbing heavy metals, for phosphate solubilization.

3. Use of a bacterium (edaphosvirga sp) according to claim 1 for promoting plant growth, promoting plant seed germination.

4. Use according to claim 2 or 3, wherein the plant is treated by root drenching or broadcasting using a suspension or broth of a strain of bacteria (Edaphovirga sp.) or an extract of a strain broth or a solid inoculum containing the strain.

5. The use according to claim 4, wherein the preparation of the suspension of the strain: taking out the bacterium (Edaphovirga sp.) strain storage tube, recovering the bacterium (Edaphovirga sp.) strain storage tube by using an LB solid culture medium, culturing the bacterium (Edaphovirga sp.) strain for 24 to 48 hours at the temperature of between 20 and 37 ℃, preparing the activated strain into a bacterial suspension by using distilled water, and measuring the concentration of the bacterial suspension by using an ultraviolet spectrophotometer at the wavelength of 600nm, wherein the concentration of the bacterial suspension is as follows: 0.1-0.8.

6. The use according to claim 4, wherein the preparation of the strain broth or strain broth extract: taking out the bacterium (Edaphovirga sp.) strain storage tube, recovering the bacterium by using an LB solid culture medium, culturing for 24-48 hours at 20-37 ℃, selecting a single colony on a flat plate, inoculating the single colony into 50ml of the LB solid culture medium, performing shake culture for 24-72 hours at 20-37 ℃ in an incubator, inoculating the single colony into the LB solid culture medium by adopting an inoculation amount of 1-10%, performing enlarged culture for 24-72 hours, and ensuring that the concentration of a bacterial liquid is more than OD (optical density)₆₀₀Finishing fermentation, and aseptically filling to obtain a liquid finished product, or freeze-drying to obtain a powdery finished product; and extracting the obtained strain fermentation liquor by using equal volume of ethyl acetate, and collecting concentrated extract liquor to obtain a strain fermentation liquor extracting solution.

7. The application of the microbial inoculum according to claim 4, wherein the preparation of the solid microbial inoculum comprises the following steps: inoculating the strain fermentation broth of claim 6 into a solid microbial inoculum culture medium, culturing at 20-40 ℃, stirring under aseptic conditions after culturing for 1-3d, and continuing culturing for 1-3d after stirring to obtain the solid microbial inoculum.

8. The use according to claim 5, 6 or 7, wherein the LB medium is formulated as: peptone 1-5%, yeast extract 0.1-5%, NaCl 0.1-3%, water 1000 ml; the LB solid culture medium comprises the following components: peptone 1-5%, yeast extract 0.1-5%, NaCl 0.1-3%, agar 1.5-2%, and water 1000 ml.

9. The use according to claim 7, wherein the formulation of the solid microbial inoculum medium is, in g/ml, 20-50% of wheat bran, 10-30% of corn flour, 1-10% of bean flour, 0.1-1% of potassium nitrate, 0.1-1% of dipotassium hydrogen phosphate, 0.4-0.7% of sodium chloride, 1-10% of calcium carbonate and 200ml of distilled water.

10. Use according to any one of claims 2 to 9, wherein the bacteria (Edaphovirga sp) are used alone or in admixture with other organic fertilizers.