CN112359000B

CN112359000B - Efficient biocontrol pseudomonas and application thereof in prevention and control of rice diseases

Info

Publication number: CN112359000B
Application number: CN202011364273.6A
Authority: CN
Inventors: 刘凤权; 孙伟波; 赵延存; 吴桂春; 汤宝; 陈贤
Original assignee: Jiangsu Academy of Agricultural Sciences
Current assignee: Jiangsu Academy of Agricultural Sciences
Priority date: 2020-11-27
Filing date: 2020-11-27
Publication date: 2022-05-10
Anticipated expiration: 2040-11-27
Also published as: CN112359000A

Abstract

The invention discloses a biocontrol strain for efficiently antagonizing main pathogenic bacteria of rice, namely pseudomonas (pseudomonas:)Pseudomonas soli) BJ 19; the strain is preserved in China general microbiological culture collection center in 30 months 6 in 2020, with the preservation number of CGMCC NO. 20163; the strain has strong plate inhibition activity on rice bacterial blight strain PXO99 and rice bacterial streak germ Rs 105; the prepared biocontrol microbial inoculum can inhibit the expansion of rice bacterial leaf blight disease spots and plays a positive role in disease control; the application of the strain can reduce the use of pesticides, protect ecological safety and agricultural production health, and have better social and economic benefits.

Description

Efficient biocontrol pseudomonas and application thereof in prevention and control of rice diseases

Technical Field

The invention belongs to the technical field of microorganisms, and particularly relates to a high-efficiency biocontrol pseudomonas BJ19 and application thereof in rice disease control.

Background

Rice is an important grain crop in the world, and the generation of various fungal and bacterial diseases seriously affects the yield and quality of the rice, thus endangering the grain safety in the world. Is prepared from Xanthomonas oryzae (Xanthomonas oryzae) Two variants of (a): bacterial blight of rice (1)Xanthomonas oryzae pv. oryzaeXoo) and bacterial leaf streak disease of rice: (Xanthomonas oryzae pv. oryzicolaXoc) is the most important Bacterial disease in rice production in China, and is the key prevention and control object in each rice area, wherein the Bacterial Blight is one of the three diseases of rice in China, usually causing yield loss of 20% -50% of rice, and the prevention and control situation is strict every yearThe severity is high.

The main prevention and treatment methods for the bacterial leaf blight of the rice comprise chemical agent prevention and treatment and cultivation of disease-resistant varieties. The currently registered chemical agents comprise chlorobromoisocyanuric acid, thienconcopper, amobam and the like, the types of the agents are more, but the problems of high drug resistance risk, environmental friendliness and the like exist, in addition, huge inter-plant variation exists among rice bacterial strains of bacterial blight, and the disease-resistant breeding is easy to lose effectiveness along with the variation of pathogenic small species of pathogenic bacteria. The biological control uses beneficial microorganisms or metabolites thereof to antagonize the expansion of pathogenic bacteria, has the advantages of environmental friendliness, contribution to ecological balance, difficulty in generating resistance and the like, and is an important component for green control of crop diseases. At present, 3 registered biological bactericides for preventing and treating bacterial blight and bacterial streak disease of rice are respectively bacillus amyloliquefaciens LX-11, bacillus subtilis and bacillus methylotrophicus LW-6, and are not registered and used by pseudomonas.

Pseudomonas bacteria (Pseudomonassp.) is a gram-negative bacterium widely distributed in soil, is a common plant rhizosphere growth promoting bacterium, has antagonistic pathogenic bacteria and plant growth promoting effects, can resist pathogenic bacteria, can also generate a series of antibacterial active products such as siderophores, antibiotics, extracellular hydrolase and the like, effectively protects plants from being invaded by pathogenic microorganisms, and is a relatively wide population for research in biological control. Pseudomonas registered for use at present is Pseudomonas fluorescens (Pseudomonas fluorescens) And rhodopseudomonas palustris PSB-S, and shenqinmycin developed by taking a main metabolite of pseudomonas, namely phenazine-1-carboxylic acid, as an active ingredient also has 4 product registrations.

The invention takes rice bacterial blight and bacterial streak germ as targets to screen out pseudomonas BJ19 with stronger antagonistic activity, and is identified as a novel pseudomonas based on 16S and gyrB genesPseudomonas soliThe application verification of the bio-control microbial inoculum is preliminarily prepared, and a new resource is provided for the biological control of rice diseases.

Disclosure of Invention

The invention aims to provide a novel fake bill with good control effect on bacterial blight and bacterial streak of riceBacteria (C)Pseudomonas soli) BJ19, expand the application prospect of pseudomonas strains, and provide a new bacterial source material for the biological control of rice diseases.

The invention realizes the technical steps that:

adopting dilution coating separation method to separate pseudomonas, code number BJ19, from rhizosphere soil of fruit tree in Guizhou, said strain is used for curing rice bacterial blight (bacterial blight of rice) on solid NA plateXanthomonas oryzae pv. oryzaeXoo PXO 99), bacterial leaf streak disease of rice (Xanthomonas oryzae pv. oryzicolaXoc RS 105) has stronger antagonistic activity. The method of colony morphology observation, physiological and biochemical indexes, 16S, gyrB gene sequence determination and comparison and the like is adopted to identify that BJ19 is pseudomonas (pseudomonas) ((bacillus subtilis))Pseudomonas soli) BJ19, no Chinese translation name exists at present. The strain is preserved in China general microbiological culture Collection center (CGMCC for short, the address: No. 3 of West Lu No. 1 of Suzhou province, the south facing the Yangyang region, Beijing, China academy of sciences, microbiological research institute, zip code 100101) in 6 months and 30 days in 2020, the preservation number is CGMCC number 20163, and the sequence is shown as SEQ ID NO: 1.

The bacterial colony characteristics of the strain on the NA medium: smooth surface without wrinkles, round edge, light brown and opaque. Gram stain negative, no spore production.

The pseudomonas can strongly inhibit the growth of the bacterial blight Xoo and the bacterial streak germ Xoc on an indoor flat plate, and the antagonistic circle method is adopted to carry out the bacteriostatic test determination, wherein the antagonistic circle diameter of the BJ19 bacterial strain on the bacterial blight Xoo is more than 70 mm, and the antagonistic circle diameter on the bacterial streak germ Xoc is more than 30 mm. The effect is stronger than the pseudomonas inhibitory activity reported or disclosed at present.

The application of the pseudomonas is to prepare the biocontrol microbial inoculum based on the strain, and the biocontrol microbial inoculum is used for controlling bacterial blight and bacterial streak disease of rice but not limited.

The biocontrol microbial inoculum is fermentation supernatant or thallus suspension of pseudomonas BJ 19.

Preparation of cell suspension: selecting activated BJ19 strain on solid NA culture medium, and sterilizing with sterilizing ringInoculating to liquid NB medium, culturing at 25-28 deg.C and 150-180rpm for 24-36 h, and adjusting OD₆₀₀= 1.0. Inoculating into large NB culture medium according to the volume ratio of 1-2%, culturing for 48-72 h under the same condition, adding sodium benzoate with mass concentration of 0.2% and Tween 80 with volume concentration of 0.1%, and obtaining the suspension of biocontrol microbial inoculum.

Preparation of fermentation supernatant: selecting the activated BJ19 strain on solid NA culture medium, inoculating to liquid NB culture medium with sterilizing ring, culturing at 25-28 deg.C and 150-₆₀₀= 1.0. Inoculating into large NB culture medium according to the volume ratio of 1-2%, performing amplification culture for 48-72 h under the same conditions, centrifuging the fermentation broth after fermentation is finished, centrifuging at 7000 rpm for 10 min to remove precipitate, collecting the supernatant, adding sodium benzoate with the mass concentration of 0.2% and Tween 80 with the volume concentration of 0.1%, and obtaining the supernatant for fermentation of the biocontrol microbial inoculum.

In the above step, the composition of NB medium: 5g/L of peptone, 10g/L of sucrose, 1g/L of yeast powder and 3g/L of beef extract, adding water to a constant volume, adjusting the pH value to 6.5-7.0, and sterilizing for 20 min by high-pressure steam at 121 ℃.

Composition of NA medium: 5g/L of peptone, 10g/L of sucrose, 1g/L of yeast powder, 3g/L of beef extract and 15g/L of agar powder, adding water to a constant volume, adjusting the pH value to 6.5-7.0, and sterilizing for 20 min by high-pressure steam at 121 ℃.

Further, the pseudomonas preparation is used for preventing and treating bacterial leaf blight and bacterial leaf streak of rice, spraying treatment is carried out before rice infection or at the early stage of rice infection, spraying treatment is carried out for 2-3 times at intervals of 7-10 days, and timely supplementary spraying is carried out after raining. Preferably, the concentration of the thallus in the spray microbial inoculum is 1 multiplied by 10⁸~1×10⁹ cfu/mL。

Compared with the prior art, the invention has the beneficial effects that:

the novel pseudomonas BJ19 provided by the invention is a biocontrol microorganism which strongly antagonizes Xao and Xoc of bacterial blight, has a good control effect on pathogenic bacteria of rice, is beneficial to reducing the use of chemical pesticides, protects the ecological environment and the quality of rice, and has good social and economic benefits.

Drawings

FIG. 1 shows the colony morphology of Pseudomonas BJ19 on NA plate medium;

FIG. 2 is a phylogenetic tree analysis based on the 16S gene sequence of Pseudomonas BJ 19;

FIG. 3 is a phylogenetic tree analysis based on the gyrB gene sequence of Pseudomonas BJ 19;

FIG. 4 shows the antagonistic activity of Pseudomonas BJ19 on NA plates against rice bacterial blight PXO 99;

FIG. 5 shows the antagonistic coil inhibitory activity of Pseudomonas BJ19 on NA plates against bacterial streak disease Rs 105;

FIG. 6 shows the effect of Pseudomonas BJ19 on inhibiting the bacterial leaf blight indoor spot expansion, wherein A is a control group inoculated with pathogenic bacteria only and not sprayed with the biocontrol agent, B is a "prevention group" and C is a "treatment group".

Detailed Description

The invention is further elucidated with reference to the drawings and the detailed description.

The present invention will be described in detail with reference to specific embodiments, but the present invention is not limited thereto. Unless otherwise specified, all technical methods used in the following examples are conventional methods; unless otherwise specified, the test materials used in the following examples are conventional chemical reagents and biochemical reagents.

The strain is separated from rhizosphere soil of a pear orchard in Bijie city, Guizhou province, biocontrol bacteria are separated and purified from an aqueous solution of a soil sample by adopting a dilution plate coating method, high-efficiency antagonistic strains are screened by adopting a flat plate antagonistic experiment method, the BJ19 strain is found to have good antagonistic effect on rice pathogenic bacteria, and the strain is identified as pseudomonas (Pseudomonas) (based on morphology and sequencing results of 16S rDNA and gyrB genes)Pseudomonas soli) BJ19, which was deposited in china general microbiological culture collection center (CGMCC, address: western road No. 1, north chen west city of chaoyang district, beijing, institute for microbiology, china academy of sciences, zip code 100101), with a accession number of CGMCC number 20163. The bacterial strains used in the test, namely, rice bacterial blight strain PXO99 and rice bacterial strainThe sexual streak germ Rs105 is a standard strain which is widely researched and is also a strain preserved in the research laboratory.

1. The culture conditions of the strains were as follows: NA solid medium composition: 5g/L of peptone, 10g/L of sucrose, 1g/L of yeast powder, 3g/L of beef extract and 15g/L of agar powder, adding water to a constant volume, adjusting the pH value to 7.0, sterilizing for 20 min by high-pressure steam at 121 ℃, cooling and then using for strain streak culture.

2. Colony characteristics: the surface on the NA medium is smooth without folds, round, light brown and opaque. Gram stain negative, no spore production.

3. The molecular structure is characterized in that: respectively adopting universal primer pairs 27F/1492R and UP1/UP2R to perform PCR amplification and sequencing on 16S and gyrB genes of the strains, placing the sequences in NCBI for Blast comparison, downloading strain sequences with the highest similarity, performing multi-sequence comparison and phylogenetic tree analysis by MEGA7.0 software, and performing 1000 times of reliability analysis on the evolutionary tree by an adjacent method. The tree building results of 16S and gyrB show that BJ19 and the model strainPseudomonas soliF-279,208 was polymerized together and was identified as PseudomonasPseudomonas soli。

4. Indoor inhibitory activity determination (inhibition zone method) of strain BJ19 on rice pathogenic bacteria:

the test is carried out in a plant protection research institute laboratory of agricultural academy of sciences of Jiangsu province. Respectively picking biocontrol strains BJ19, rice bacterial blight PXO99 and rice bacterial leaf streak germ Rs105 on an NA plate for activation culture, and growing colonies after 1-2 days. And (3) selecting a single colony, inoculating the single colony in a small amount of NB culture medium, shaking for 1-2 days at 28 ℃, and then taking out a culture solution. Heating and melting the NA solid culture medium in a microwave oven, when the culture medium is cooled to 40-50 ℃, respectively taking 100 mu L of PXO99 and Rs105 bacterial liquid, uniformly mixing the bacterial liquid with 50 mL of NA culture medium, and pouring the mixture into a flat plate, wherein the diameter of the culture dish is 90 mm. After cooling the plate with bacteria, 3. mu.L of BJ19 bacteria solution was dropped into the center, and then the plate was incubated in an incubator at 28 ℃. After 3-4 days the pathogens had grown out on the plate, the antagonistic circle size was measured with a ruler, and each treatment was repeated 5 times.

The measurement results are shown in table 1:

the results in Table 1 show that the BJ19 strain has an antagonistic circle diameter of >70 mm against Xanthomonas oryzae Xoo and an antagonistic circle diameter of >30 mm against bacterial streak germ Xoc, which is stronger than the currently reported or published Pseudomonas inhibitory activity.

Pseudomonas for rice bacterial leaf blight (Xanthomonas oryzae pv. oryzaeXoo PXO 99), bacterial leaf streak disease of rice (Xanthomonas oryzae pv. oryzicolaXoc RS 105) has stronger antagonistic activity.

5. The inhibitory activity of the strain BJ19 biocontrol microbial inoculum on rice bacterial leaf blight scab (indoor small hole test):

the test is carried out in a plant protection research institute laboratory of agricultural academy of sciences of Jiangsu province. The rice bacterial leaf blight strain PXO99 is respectively shake-cultured by using 100 mL of NB culture medium to prepare bacterial suspension.

Preparing a bio-control microbial agent suspension: selecting BJ19 strain activated on solid NA culture medium, inoculating to liquid NB culture medium with sterilizing ring, culturing at 28 deg.C and 180rpm for 36 hr, and adjusting OD₆₀₀= 1.0. Inoculating into a large-scale NB culture medium according to the proportion of 1% by volume for amplification culture, culturing for 72 h under the same condition, adding sodium benzoate with the mass concentration of 0.2% and Tween 80 with the volume concentration of 0.1%, and obtaining the biocontrol microbial inoculum suspension for later use.

Wherein, the composition of the NB culture medium is as follows: 5g/L of peptone, 10g/L of sucrose, 1g/L of yeast powder and 3g/L of beef extract, adding water for constant volume, adjusting the pH value to 7.0, and sterilizing for 20 min by high-pressure steam at 121 ℃. NA solid medium composition: 5g/L of peptone, 10g/L of sucrose, 1g/L of yeast powder, 3g/L of beef extract and 15g/L of agar powder, adding water to a constant volume, adjusting the pH value to 7.0, and sterilizing for 20 min by high-pressure steam at 121 ℃.

The selected rice seeds are susceptible varieties IR 24. Taking rice seedlings growing in the two-leaf stage in an incubator, dipping PXO99 bacterial liquid by using sterilizing scissors, and then cutting off the upper parts of the leaves by adopting a leaf cutting method, namely inoculating pathogenic bacteria into wounds of the rice leaves. Placing in a constant temperature incubator at 28 ℃, and culturing alternately in darkness for 12 h and illumination for 12 h. Taking out rice seedlings one day later, spraying BJ19 biocontrol agent on leaves by using a sterile spraying can, and then putting the leaves into an incubator for cultivation. After two weeks, the control group had a severe disease, the rice seedlings were removed and attached to a white adhesive plate, and the length of the bacterial blight lesions was measured with a ruler. Each treatment is repeated by setting 3 small-hole rice seedlings, and 15 leaves are taken for statistics. The test sets that pathogenic bacteria are firstly inoculated and then inoculated as a treatment group, pathogenic bacteria are firstly inoculated and then inoculated as a prevention group, and only pathogenic bacteria are inoculated as a control group, and the total number of the test treatments is 4. Relative inhibition (%) = (control lesion length-treatment lesion length)/control lesion length × 100.

The results of the lesion length measurements are shown in table 2:

the results in table 2 show that rice seedlings treated by the BJ19 biocontrol microbial inoculum can effectively inhibit the extension of bacterial leaf blight, the inhibition rate is more than 70%, the treatment effect is lower than the prevention effect, but is more than 50%, and a reference method is provided for applying the BJ19 microbial inoculum in the field.

6. The bacterial strain BJ19 biocontrol microbial inoculum has the following effects on controlling bacterial blight of rice (field test):

the test is carried out in Xuyi county, Jiangsu, Xuyi county, Ningzhen Tokyo, New bridge village. About 10L of BJ19 microbial inoculum is prepared according to the preparation method of the biocontrol preparation. The variety of the paddy rice is C Liangyou 0861. 12 cells are arranged in the field, the specification of each cell is 5 m multiplied by 5 m, the cells are arranged according to a random block design, 6 cells are set to be treated by BJ19 biocontrol microbial inoculum, and 6 cells are set to be clear water blank control. A small amount of diseases are found in the rice booting stage survey in 8-month and 12-day days, the first pesticide is applied in 8-month and 15-day days, then the first pesticide is applied every 10-12 days, and the pesticide is timely applied after rain. The field disease condition is investigated in the near-maturity stage. Sampling 5 points in each cell, collecting 100 leaves in total, and counting the number of diseased leaves according to the following classification standard: grading the disease condition standard: grade 0, no disease; grade 1, the lesion area is below 1/5; stage 2, the lesion area is below 1/3; grade 3, the lesion area is below 1/2; and 4, the lesion area is more than 1/2. Disease index = (number of diseased leaves at each level × number of levels)/(number of investigated total leaves and fruits × 4) × 100. The prevention and treatment effect = (disease index of control group-disease index of treatment group)/disease index of control group x 100%.

The test results are shown in table 3:

the results in table 3 show that the BJ19 biocontrol microbial inoculum has a good inhibiting effect on the bacterial leaf blight of rice in a field, the control effect is more than 60%, most of disease loss can be reduced, the rice yield is protected from being seriously affected by diseases, and the biocontrol microbial inoculum has a certain reference application value in production.

7. The bacterial strain BJ19 biocontrol microbial inoculum has the control effect on rice bacterial streak (field test):

preparation of fermentation supernatant: selecting activated BJ19 strain on solid NA culture medium, inoculating to liquid NB culture medium with sterilizing ring, culturing at 28 deg.C and 180rpm for 36 hr, and adjusting OD₆₀₀= 1.0. Inoculating a large NB culture medium according to the proportion of 1% of the volume ratio for enlarged culture, culturing for 72 h under the same condition, centrifuging the fermentation liquor after finishing the fermentation, centrifuging at the rotating speed of 7000 rpm for 10 min to remove the precipitate, taking the supernatant, adding sodium benzoate with the mass concentration of 0.2% and tween 80 with the volume concentration of 0.1% to obtain the supernatant of the biocontrol bacterium fermentation for later use.

The prevention and treatment test is carried out in Xuyi county, Weiqiao, county, Mu shop and town, Jiangsu province. About 5L of BJ19 microbial inoculum is prepared according to the preparation method of the biocontrol preparation. 6 cells are arranged in the field, the specification of each cell is 5 m multiplied by 5 m, the cells are arranged according to a random block design, wherein 3 cells are treated by BJ19 biological anti-microbial agents, and 3 cells are used as clear water blank contrast. A small amount of diseases are found in the rice booting stage survey in 8-month and 10-day, the first pesticide is applied in 8-month and 14-day, then the first pesticide is applied every 10-12 days, and the pesticide is timely applied after rain. And (5) investigating the field morbidity in the near-mature period. Sampling 5 points in each cell, collecting 100 leaves in total, and counting the number of diseased leaves according to the following classification standard: grading the disease condition standard: grade 0, no disease; grade 1, the lesion area is below 1/5; stage 2, the lesion area is below 1/3; grade 3, the lesion area is below 1/2; and 4, the lesion area is more than 1/2. Disease index = (number of diseased leaves at each level × number of levels)/(number of investigated total leaves and fruits × 4) × 100. Control effect = (control group disease index-treatment group disease index)/control group disease index x 100%.

The test results are shown in table 4:

the results in Table 4 show that the fermentation supernatant of BJ19 has good control effect on rice bacterial leaf streak, the control effect is over 60 percent, and the disease loss can be reduced.

The experiment shows that the pseudomonas BJ19 and the biocontrol microbial inoculum thereof provided by the invention can effectively control main bacterial diseases of rice, have good inhibitory activity on bacterial blight and bacterial streak of rice, and have good application prospect in the biological control of rice diseases.

The above-mentioned experiments are only preferred examples of the present invention, and should not be construed as limiting the technical scope of the present invention, and all modifications, substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Sequence listing

<110> agricultural science and academy of Jiangsu province

<120> high-efficiency biocontrol pseudomonas and application thereof in prevention and control of rice diseases

<160> 2

<170> SIPOSequenceListing 1.0

<210> 1

<211> 1417

<212> DNA

<213> Pseudomonas soli (Pseudomonas soli)

<400> 1

accatgcaag tcgagcggat gacgggagct tgctccttga ttcagcggcg gacgggtgag 60

taatgcctag gaatctgcct ggtagtgggg gacaacgttt cgaaaggaac gctaataccg 120

catacgtcct acgggagaaa gcaggggacc ttcgggcctt gcgctatcag atgagcctag 180

gtcggattag ctagtaggtg aggtaatggc tcacctaggc gacgatccgt aactggtctg 240

agaggatgat cagtcacact ggaactgaga cacggtccag actcctacgg gaggcagcag 300

tggggaatat tggacaatgg gcgaaagcct gatccagcca tgccgcgtgt gtgaagaagg 360

tcttcggatt gtaaagcact ttaagttggg aggaagggtt gtacgctaat accgtgcaat 420

tttgacgtta ccgacagaat aagcaccggc taactctgtg ccagcagccg cggtaataca 480

gagggtgcaa gcgttaatcg gaattactgg gcgtaaagcg cgcgtaggtg gttcgttaag 540

ttggatgtga aagccccggg ctcaacctgg gaactgcatc caaaactggc gagctagagt 600

atggtagagg gtgggtggaa tttcctgtgt agcggtgaaa tgcgtagata taggaaggaa 660

caccagtggc gaaggcgacc acctggactg atactgacac tgaggtgcga aagcgtgggg 720

agcaaacagg attagatacc ctggtagtcc acgccgtaaa cgatgtcaac tagccgttgg 780

aatccttgag attttagtgg cgcagctaac gcattaagtt gaccgcctgg ggagtacggc 840

cgcaaggtta aaactcaaat gaattgacgg gggcccgcac aagcggtgga gcatgtggtt 900

taattcgaag caacgcgaag aaccttacca ggccttgaca tgcagagaac tttccagaga 960

tggattggtg ccttcgggaa ctctgacaca ggtgctgcat ggctgtcgtc agctcgtgtc 1020

gtgagatgtt gggttaagtc ccgtaacgag cgcaaccctt gtccttagtt accagcacgt 1080

tatggtgggc actctaagga gactgccggt gacaaaccgg aggaaggtgg ggatgacgtc 1140

aagtcatcat ggcccttacg gcctgggcta cacacgtgct acaatggtcg gtacagaggg 1200

ttgccaagcc gcgaggtgga gctaatctca caaaaccgat cgtagtccgg atcgcagtct 1260

gcaactcgac tgcgtgaagt cggaatcgct agtaatcgca aatcagaatg ttgcggtgaa 1320

tacgttcccg ggccttgtac acaccgcccg tcacaccatg ggagtgggtt gcaccagaag 1380

tagctagtct aaccttcggg aggacggtac cacggtg 1417

<210> 2

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gtccggcggt ctgcacggtg taggtgtatc ggttgtgaat gccctgtcgg aacagctagt 60

gctcaccgtt cgtcgtagcg gcaagatctg ggaacagacc tacgtccatg gcgtgcccca 120

agcgccgatg gcggtcgtgg gtgacagcga aaccaccggt acccacattc acttcaagcc 180

ttcggctgaa actttcaaga acatccactt cagctgggac atcctcgcca agcgtatccg 240

cgagctgtcg ttcctgaact ccggcgtcgg tatcctgttg aaggatgagc gcagcggcaa 300

ggaagagttc ttcaagtacg agggtggcct gcgtgcattt gttgagtacc tgaataccaa 360

caagactccg gtcaactccc aggtattcca cttcaatgtc cagcgtgaag atggcgtggg 420

cgttgagatt gccctgcagt ggaacgacag cttcaacgaa aacctgctgt gcttcaccaa 480

caacattccc cagcgcgatg gtggtaccca cctggtcggc ttccgttcct cgcttacccg 540

tagcctgaac agctatatcg agcaggaagg cctggcgaaa aagaacaagg ttgccaccac 600

cggtgacgac gcccgtgaag gcttgactgc gatcatttcg gtcaaggtgc cggatccgaa 660

gttcagctcg cagaccaagg acaagctggt ttcctcggag gtgaagaccg ccgtggaaca 720

ggagatgaac aaatacttcg ccgacttcct gttggagaac cccaacgaag ccaaggccgt 780

agtcggcaag atgatcgatg ccgcacgtgc ccgtgaagcg gcgcgtaaag cgcgcgagat 840

gactcgtcgc aaaggcgccc tggatatcgc tggcctgcca ggtaaactgg ccgactgcca 900

ggagaaggac cctgcccttt ccgaactgta cctggtggag ggtgactccg cgggtggctc 960

ggccaagcaa ggccgcaacc gtcgcaccca ggctatcttg ccgctgaagg gcaagatcct 1020

caacgtcgag aaagcacgct tcgacaagat gatctcctcg caggaggtcg gcacgttgat 1080

caccgcactg ggctgtggca tcggccgcga agagtacaac atcgacaa 1128

Claims

1. Pseudomonas spPseudomonas soliBJ19, preserved in China general microbiological culture Collection center with the preservation number of CGMCC NO.20163 and the preservation date of 2020, 6 and 30 days.

2. The pseudomonad of claim 1, wherein said pseudomonad has antagonistic activity against bacterial blight of rice, bacterial streak of rice.

3. A biocontrol microbial inoculum prepared from pseudomonas BJ19 of claim 1.

4. The biocontrol microbial inoculum of claim 3 which is fermentation supernatant or microbial suspension of pseudomonas BJ 19.

5. The biocontrol microbial inoculum according to claim 4, wherein the preparation method of the biocontrol microbial inoculum cell suspension is as follows: inoculating Pseudomonas BJ19 on solid NA culture medium into liquid NB culture medium, culturing for 24-36 h, and regulating OD₆₀₀=1.0，Inoculating the liquid NB culture medium according to the volume ratio of 1-2% for amplification culture for 48-72 h, and adding sodium benzoate with the mass concentration of 0.2% and Tween 80 with the volume concentration of 0.1% to obtain the biocontrol microbial inoculum suspension.

6. The biocontrol microbial inoculum of claim 4, wherein the preparation method of the fermentation supernatant of the biocontrol microbial inoculum is as follows: inoculating Pseudomonas BJ19 on solid NA culture medium into liquid NB culture medium for 24-36 h, and regulating OD₆₀₀And =1.0, inoculating the supernatant into a liquid NB culture medium according to the volume ratio of 1-2%, performing amplification culture for 48-72 h, centrifuging to obtain a supernatant, and adding sodium benzoate with the mass concentration of 0.2% and tween 80 with the volume concentration of 0.1% into the supernatant to obtain a supernatant for fermentation of the biocontrol microbial inoculum.

7. The biocontrol microbial inoculum according to claim 5 or 6, characterized in that: the temperature of the culture is 25-28 ℃, and the rotation speed is 150-180 rpm.

8. The biocontrol microbial inoculum of claim 5 or 6, wherein the composition of the NB medium is as follows: 5g/L of peptone, 10g/L of sucrose, 1g/L of yeast powder, 3g/L of beef extract and 6.5-7.0 of pH.

9. The biocontrol microbial inoculum of claim 5 or 6, characterized in that the composition of the NA medium is: 5g/L of peptone, 10g/L of sucrose, 1g/L of yeast powder, 3g/L of beef extract, 15g/L of agar powder and 6.5-7.0 of pH value.

10. The use of the biocontrol microbial inoculum of claim 3 for controlling bacterial blight and bacterial streak of rice.