CN110982724A

CN110982724A - Bacillus for antagonizing phytopathogen and promoting rooting and application thereof

Info

Publication number: CN110982724A
Application number: CN201811148417.7A
Authority: CN
Inventors: 陈峥; 朱育菁; 郑梅霞; 刘波; 许炼; 潘志针; 肖荣凤; 邓文琼; 李慧敏
Original assignee: Institute of Agricultural Biological Resources of Fujian Academy of Agricultural Sciences
Current assignee: Institute of Agricultural Biological Resources of Fujian Academy of Agricultural Sciences
Priority date: 2018-09-29
Filing date: 2018-09-29
Publication date: 2020-04-10

Abstract

The invention provides a Bacillus for antagonizing phytopathogens and promoting rooting and application thereof, wherein the Bacillus is Bacillus velezensis FJAT-47164 with the scientific name of Bacillus velezensis FJAT-47164, which is preserved in the China general microbiological culture Collection center with the preservation number of CGMCC NO. 15948. The bacillus of the invention can not only inhibit plant pathogenic bacteria, but also promote plant rooting, can be used for early prevention of blight, and is a biocontrol bacterium which is environment-friendly, economic and effective in disease control.

Description

Bacillus for antagonizing phytopathogen and promoting rooting and application thereof

Technical Field

The invention belongs to the technical field of microorganisms, and particularly relates to a bacillus strain for antagonizing phytopathogens and promoting rooting.

Background

Blight is a systemic infectious disease, is a common soil-borne disease of plants such as Mongolia, soybean, wheat, tomato, cotton, strawberry, and the like, and is an increasingly prominent problem in the United states, Canada, Australia, China, and the like. The plant withers due to blight, leaves become small, the plant lacks luster, branches are dwarfed, fruits are thin and small, or leaves become yellow and wilted, and the plant gradually withers when the plant is serious. The main pathogenic populations of the blight are Fusarium oxysporum and Fusarium solani, the prevention and treatment methods comprise chemical reagents, funguses, biological prevention and treatment, phytotherapeutic drugs, optimized fertilization and the like, and the biocontrol bacterium is an important measure for comprehensive prevention and treatment.

Various fungi, bacteria and some actinomycetes can be applied to biological control of fungal diseases, and antagonistic bacteria include brevibacillus brevis, pseudomonas aeruginosa, bacillus belgii and the like. The application research of bacteria in the biological control of plants is widely carried out, and good application effect is obtained. However, these bacteria do not have a good control effect on plant blight.

Therefore, screening of biocontrol bacteria with good control effect and wide adaptability is a key problem in the biological control work of plant blight. Moreover, if biocontrol bacteria that can be used in the early stage of plant growth can be screened, phytopathogens can be prevented early, the occurrence of plant diseases such as blight and the like can be reduced, and the crop yield can be improved.

Disclosure of Invention

Therefore, a biocontrol bacterium for antagonizing phytopathogen is needed to solve the biological control problem of the blight.

In order to achieve the purpose, the inventor provides the following technical scheme:

the Bacillus for antagonizing phytopathogens and promoting rooting is Bacillus velezensis FJAT-47164, is named as Bacillus velezensis FJAT-47164, is preserved in the common microorganism center of China Committee for culture Collection of microorganisms, has the preservation number of CGMCC NO.15948, has the preservation date of 2018, 6 and 19 days and has the preservation address of the institute of microbiology, China academy of sciences, Beijing, China.

The colony morphology of the bacillus FJAT-47164 is as follows: faint yellow, round and raised, opaque, neat-edged, smooth and moist microcolonies on the surface.

The bacillus FJAT-47164 has strong antagonistic action on fusarium oxysporum, including tomato host fusarium oxysporum FJAT-30512, banana host fusarium oxysporum FJAT-370 and watermelon host fusarium oxysporum FJAT-30265, and has strong antagonistic action on carpet xanthium spores FJAT-10151.

Furthermore, the antagonistic phytopathogen and the rooting-promoting bacillus are applied to antagonistic phytopathogens.

Specifically, the bacillus is prepared into an antibacterial solution, and the antibacterial solution is irrigated on the root system of the plant seedling by a root irrigation method or sprayed on plant leaves or fruits.

The preparation method of the bacteriostatic solution comprises the steps of inoculating the bacillus strain to a solid culture medium plate, selecting a single colony of a strain ring, inoculating the single colony of the strain ring to a corresponding liquid culture medium, and culturing at the constant temperature of 25-35 ℃ for 36-60 h; and (3) centrifuging the bacillus fermentation liquor, discarding the thallus, and taking the supernatant to obtain the antibacterial solution.

Furthermore, the antagonistic phytopathogen and the rooting-promoting bacillus are applied to promoting the germination of plant seeds.

Specifically, the bacillus suspension is used for soaking seeds for 6-8h, the seeds are covered by a wet gauze bag at 25-28 ℃ for accelerating germination for 2-3 days, when 1/2-2/3 seeds are exposed, the seeds can be sowed, and the substrate can be seedling raising soil or seedling raising blocks.

The preparation method of the bacillus bacterial suspension comprises the steps of inoculating bacillus strains on a solid culture medium flat plate, selecting a single bacterial colony with a bacterial ring, inoculating the single bacterial colony into a corresponding liquid culture medium, culturing at the constant temperature of 25-35 ℃ for 36-60h, and diluting the cultured bacterial liquid until the bacterial concentration is 1-4 multiplied by 10⁵cfu·mL^-1And (4) finishing.

Further, the solid culture medium is an LB solid culture medium, and the corresponding liquid culture medium is an LB liquid culture medium.

The invention has the beneficial effects that:

(1) the bacillus FJAT-47164 screened from Tibet Namu Miyao national park yak dung has strong inhibition effect on fusarium which is the main pathogenic bacterium of fusarium wilt, and can be specially used for preventing and treating fusarium wilt.

(2) The bacillus FJAT-47164 is antagonistic bacteria of plant pathogenic bacteria, especially antagonistic bacteria of main pathogenic bacteria of blight, and is a biocontrol bacterium which is environment-friendly, economical and effective for preventing and treating diseases. It can produce endospore (spore) with strong stress resistance, can resist salt, acid and high temperature, is easy to store and transport, and is favorable for quickly realizing commercial production.

(3) The bacillus FJAT-47164 has obvious bacteriostasis effect and obvious plant rooting promoting effect. Can be applied in the stage of plant seeds to prevent the occurrence of plant diseases as soon as possible.

Drawings

FIG. 1 shows the antagonistic effect of FJAT-47164 on Fusarium oxysporum of 3 different hosts according to an embodiment. A. B, C plates of three rows are respectively inoculated with Fusarium oxysporum FJAT-30512, Fusarium oxysporum FJAT-370 and Fusarium oxysporum FJAT-30265, the left panel is blank control, and the right panel is streak-inoculated FJAT-47164 strain.

FIG. 2 is a colony morphology of Bacillus FJAT-47164, wherein the left image is a colony growth state of FJAT-47164 strain on a whole plate, and the right image is a partial enlarged view of the colony on the left image.

FIG. 3 is a tree showing the results of identifying the 16S rRNA sequence of Bacillus FJAT-47164 according to an embodiment.

FIG. 4 shows the effect of Bacillus FJAT-47164 on the germination of mung bean seeds according to an embodiment.

FIG. 5 shows the effect of Bacillus FJAT-47164 on the root length of mung bean seeds and the stem length of mung bean sprouts according to an embodiment.

FIG. 6 shows the pot culture results of mung bean seeds according to the embodiment.

Detailed Description

To explain technical contents, achieved objects and effects of the technical solutions in detail, the following detailed description is given with reference to the accompanying drawings in combination with specific embodiments.

Example 1 screening of antagonistic strains

1. Soil sample collection and bacillus separation and purification

Preparing suspension from Yak dung in national park of Xizanamu, diluting with sterile water, and coating LB plate (LB: tryptone 10 g.L)^-1 Sodium chloride 10 g.L^-1Yeast powder 5 g.L^-1Agar powder 1.5%, pH 7.0-7.2); culturing at 30 deg.C for 48h, selecting single colony, and storing in glycerol as strain to be tested. And (3) separating and purifying by adopting a dilution plate coating method to obtain 58 strains serving as strains to be detected.

2. Screening of biocontrol strain for blight

(1) Initial sieve by face-off method

The test strains are activated on an LB medium plate and cultured for 48h at the constant temperature of 30 ℃.

Fusarium oxysporum FJAT-30512 (Qian Chen, Liubo, Liu Guo hong, Majia Mei, Gong Hai Yan. Paris polyphylla rhizosphere geobacillus diversity research [ J ]. tropical agricultural science, 2015,35(12): 103-.

Fusarium oxysporum FJAT-30512, FJAT-370, FJAT-30265 in potato dextrose agar medium (PDA: potato 200.0 g.L)^-120.0 g.L of sucrose^-1Agar 15 g. L^-1) Activating, and culturing at 28 deg.C for 48 h. Inoculating activated Fusarium oxysporum on a PDA plate, culturing at 28 deg.C for 120h until mycelia grow over the plate, making a small colony with a diameter of 9mm on the colony cake, placing in the middle of the PDA plate, and inoculating test strains by drawing a line with a length of 40mm at a distance of 22mm from the periphery of the small colony. Culturing at 28 deg.C for 120h, and observing the inhibiting effect of the strain on Fusarium oxysporum.

58 strains obtained by separation and purification in Tibet area are primarily screened by a plate-confrontation method to obtain 1 strain FJAT-47164 which has antagonistic action on Fusarium oxysporum fungi FJAT-30512, FJAT-370 and FJAT-30265 of different hosts. The results of the experiment are shown in FIG. 1.

(2) Bacterial inhibition ring method double screen

And (3) carrying out bacterial inhibition circle method rescreening on 1 strain FJAT-47164 which has an inhibiting effect on different host fusarium oxysporum in the primary screening. The test strain FJAT-47164 was inoculated on an LB plate, and 1 loopful of a single colony was picked up and inoculated on 10mL of LB liquid medium (tryptone 10 g. L)^-1 Sodium chloride 10 g.L^-1Yeast powder 5 g.L^-1pH 7.0-7.2) at 170 r.min^-1Culturing at 30 deg.C for 48h, counting with blood ball counter plate, and making FJAT-47164 colony density reach 2.232 × 10⁸cfu·mL^-1. And (3) centrifuging the fermentation liquor of FJAT-47164 for 8min at 4000rpm, taking the supernatant, and discarding the thallus.

a. Screening of biocontrol bacteria of tomato wilt

2mL of a bacterial suspension of tomato host Fusarium oxysporum FJAT-30512 (colony density 2.31X 10)⁷cfu·mL^-1) With 100mL of a solution containing 150. mu.g.mL at 50 DEG C^-1PDA semisolid culture medium of streptomycin(PDA: Potato 200.0 g.L^-120.0 g.L of sucrose^-1Agar 9 g. L^-1) After mixing, 4mL of the mixture was aspirated and poured into a prepared container containing 150. mu.g.mL^-1Preparing a streptomycin PDA solid culture medium (the quantitative amount of each plate is 20mL) into a double-layer plate containing pathogenic bacteria; after the culture medium is solidified, a hole (diameter 9mm) is punched, 100 mu L of supernatant of the test strain is added into the hole, the negative control is 100 mu L of sterile water, and the positive control is 100 mu L of hygromycin (mass concentration is 0.25 mg/mL)^-1) Repeating the culture for 3 times for each test strain, culturing at 28 ℃ for 1-2d, and measuring the diameter of the inhibition zone by using a diameter crossing method. The bacteriostatic effect is shown in table 1.

TABLE 1 bacteriostatic action of FJAT-47164 strain on Fusarium oxysporum FJAT-30512 as tomato host

Unit: mm is

Note: the zone diameter comprises the hole punch diameter.

b. Screening of biocontrol bacterium of banana wilt

2mL of bacterial suspension of banana host Fusarium oxysporum FJAT-370 (colony density 2.52X 10)⁷cfu·mL^-1) Mixing with 100mL of 50 ℃ PDA semisolid culture medium (containing 150. mu.g.mL)^-1Streptomycin), 4mL of the mixture was aspirated and poured into a prepared solution containing 150. mu.g.mL^-1Preparing a streptomycin PDA solid culture medium (the quantitative amount of each plate is 20mL) into a double-layer plate containing pathogenic bacteria; after the culture medium is solidified, a hole (diameter 9mm) is punched, 100 mu L of supernatant of the test strain is added into the hole, the negative control is 100 mu L of sterile water, and the positive control is 100 mu L of hygromycin (mass concentration is 0.25 mg/mL)^-1) Repeating the culture for 3 times for each test strain, culturing at 28 ℃ for 1-2d, and measuring the diameter of the inhibition zone by using a diameter crossing method. The bacteriostatic effect is shown in table 2.

TABLE 2 bacteriostatic action of FJAT-47164 strain on banana host Fusarium oxysporum FJAT-370

Unit: mm is

Note: the zone diameter comprises the hole punch diameter.

c. Screening of watermelon wilt biocontrol bacteria

2mL of a bacterial suspension of watermelon host Fusarium oxysporum FJAT-30265 (colony density 2.14X 10)⁷cfu·mL^-1) Mixing with 100mL of 50 ℃ PDA semisolid culture medium (containing 150. mu.g.mL)^-1Streptomycin), 4mL of the mixture was aspirated and poured into a prepared solution containing 150. mu.g.mL^-1Preparing a streptomycin PDA solid culture medium (the quantitative amount of each plate is 20mL) into a double-layer plate containing pathogenic bacteria; after the culture medium is solidified, a hole (diameter 9mm) is punched, 100 mu L of supernatant of the test strain is added into the hole, the negative control is 100 mu L of sterile water, and the positive control is 100 mu L of hygromycin (mass concentration is 0.2 mg/mL)^-1) Repeating the culture for 3 times for each test strain, culturing at 28 ℃ for 1-2d, and measuring the diameter of the inhibition zone by using a diameter crossing method. The bacteriostatic effect is shown in table 3.

TABLE 3 bacteriostatic action of FJAT-47164 strain on watermelon host Fusarium oxysporum FJAT-30265

Unit: mm is

Note: the zone diameter comprises the hole punch diameter.

In conclusion, a strain FJAT-47164 with strong inhibition effect on fusarium solani, fusarium banana, and fusarium watermelon is screened from Yak dung in national parks of Nameu, Tibet. By utilizing the effect of the bacterial strain FJAT-47164 on antagonism of fusarium oxysporum, the bacterial liquid or fermentation supernatant of the bacterial strain FJAT-47164 can be irrigated to the root systems of plant seedlings such as tomato seedlings, watermelon seedlings or banana seedlings by a root irrigation method and is used for preventing and treating the blight.

Example 2 identification of antagonistic strains

1. Morphological characteristics

The FJAT-47164 strain was activated on LB plates and after 48h the colony morphology, size, color, transparency, protrusion and edge condition of the strain were observed.

The colony characteristics of the strain FJAT-47164 are shown in FIG. 2, and the colony is a faint yellow, round and raised colony, opaque, neat edge, and smooth and moist microcolony.

2.16S rRNA Gene sequence analysis

Extracting genome DNA of a strain FJAT-47164 by adopting a Tris-saturated phenol method, carrying out PCR amplification by adopting 16S rRNA gene universal primers 27F and 1492R, carrying out PCR reaction program according to the literature of Zhengxuefang and the like (Zhengxuefang, Liubo, Zhuyancyanine, and the like; screening and identification of bacillus solani wilt biocontrol strain [ J ]. the Chinese biological control report, 2016,32(5):657 and 665.), sending the PCR product to Shanghai Boshang sequencing, using EZBioCloud to complete sequence homology comparison, analyzing the sequence and constructing a phylogenetic tree by MEGA 6.0.6 software.

Comparing the 16S rRNA gene sequence of the strain FJAT-47164 with an EZBioCloud gene database, the genetic relationship between the strain FJAT-47164 and Bacillus velezensis is nearest, the 16S rRNA gene homology is 99.86 percent, so the strain FJAT-47164 belongs to Bacillus velezensis Belgium budSporeA bacillus. Downloading 16SrRNA gene sequences of strains with higher homology, carrying out comparative analysis, constructing a phylogenetic tree, and forming the phylogenetic tree as shown in figure 3 when a neighbor-Joining method is adopted and the Bootstrap value is 1000 times. In the constructed phylogenetic tree, the strain FJAT-47164 and Bacillus velezensis are gathered in the same branch.

Example 3 inhibitory Effect of Bacillus on other bacteria

(1) Preparation of bacillus FJAT-47164 bacteriostatic solution

Inoculating Bacillus strain FJAT-47164 on LB plate, picking 1 ring single colony to 10mL LB liquid culture medium, 170 r.min^-1Culturing at 30 deg.C for 48h, counting with blood ball counter plate, and making FJAT-47164 colony density reach 2.232 × 10⁸cfu·mL^-1. And centrifuging the fermentation liquor of FJAT-47164 at 4000rpm for 8min, discarding thalli, and taking supernatant to obtain the antibacterial solution.

(2) Inhibition effect of bacteriostatic solution on xanthomonas carpi

1mL of Xanthomonas carpropoides (Xanthomonas axonopodis) FJAT-10151 (preserved in China for culture collection management of microorganisms)Bacterial suspension (colony density 4.224 multiplied by 10) of the committee common microbiological center with preservation number CGMCC NO.10271⁸cfu·mL^-1) Mixing with 200mL of NA semisolid culture medium (beef extract 3g, peptone 5g, glucose 10g, agar 9g, and water 1L) at 50 ℃, sucking 4mL, pouring into prepared NA solid culture medium (beef extract 3g, peptone 5g, glucose 10g, agar 18g, and water 1L), and quantifying each plate to be 20mL to prepare double-layer plates containing pathogenic bacteria; after the culture medium is solidified, punching a hole (diameter is 6mm), adding 80 mu L of antibacterial solution into the hole, wherein the negative control is 80 mu L of sterile water, and the positive control is 80 mu L of streptomycin (mass concentration is 0.06 mu g.mL)^-1) And repeating the experiment for 3 times, culturing at the constant temperature of 28 ℃ for 1-2 days, and measuring the diameter of the inhibition zone by using a diameter crossing method. The bacteriostatic effect is shown in table 4.

TABLE 4 bacteriostatic action of bacteriostatic solution on Xanthomonas carpi FJAT-10151

Unit: mm is

Note: the zone diameter comprises the hole punch diameter.

The bacillus FJAT-47164 can inhibit xanthomonas carpi. The Xanthomonas carpesii is a typical plant pathogenic bacterium and can cause plant diseases such as bacterial leaf spot of anthurium andraeanum, bacterial leaf blight of cotton beans, citrus canker and the like. Therefore, the bacteriostatic solution prepared by the bacillus FJAT-47164 can be sprayed on plant leaves or fruits for preventing and treating phytopathogen.

Example 4 root-promoting action of Bacillus

Inoculating Bacillus strain FJAT-47164 on LB plate, picking 1 ring single colony to 10mL LB liquid culture medium, 170 r.min^-1Culturing at 30 deg.C for 48h, counting with blood ball counter plate, and making FJAT-47164 colony density reach 2.232 × 10⁸cfu·mL^-1。

The bacterial suspension is subjected to gradient dilution, 1200 times, 600 times, 300 times, 150 times and 50 times of the bacterial suspension, the stock solution is respectively diluted, and clear water is used as a control (ck). Selecting mung bean seeds with relatively consistent growth vigor, placing the mung bean seeds in a transparent culture box of 9cm with 2-3 layers of filter paper laid at the bottom, placing 15 mung bean seeds in a constant-temperature artificial climate box at 27 ℃, and illuminating for 16h and dark for 8 h. Tracking and observing the germination condition of the mung beans, recording the germination number until no new germination grains appear in 3 days continuously, measuring the germ length of a mung bean germination radicle machine, and analyzing the influence of bacillus FJAT-47164 on the germination of mung bean seeds.

The experimental result shows that when 48 hours, compared with a control group, the diluted bacterial liquid group and the control group obviously germinate, namely 2/3 seeds are exposed, and the stock solution inhibition effect is obvious; at 72h, comparing the experimental group with the control group, and with the increase of the dilution times, the growth state of the experimental group is positively correlated; at 96h, compared with a control group, the growth state of the experimental group is positively correlated with the increase of the dilution factor, the stock solution inhibition effect is obvious, and the germination is stopped.

The germination effect of Bacillus fJAT-47164 on mung bean seed germination is shown in Table 5 and FIG. 4. The experimental result shows that the germination index of the mung bean seeds is as follows: the experimental group and the control group have no obvious difference and have no obvious inhibition and promotion effects; seed vigor: the dilution of 300 times and 1200 times has promoting effect, wherein the dilution of 600 times has the best effect, and when the dilution of 600 times is 600 times, the effect is obviously different from that of other groups, and is 114.93% of the growth of a control group.

TABLE 5 Effect of Bacillus FJAT-47164 on mung bean seed Germination

In the above table,% germination is (number of germinated seeds on specified days/number of test seeds) × 100%;

the germination index ═ Σ (Gt/Dt), where Gt is the number of germinated seeds on day t and Dt is the corresponding number of days of germination;

viability index ═ germination index × embryo root length (cm);

abcd indicates significant difference (P < 0.05).

At 72h, the effect of Bacillus FJAT-47164 on the root length of mung bean seeds is shown in Table 6, and FIG. 5 and FIG. 6. The experimental result shows that the mung bean sprouts have long roots: the bacterial liquid dilution effect of 600 times is the best, and the bacterial liquid dilution effect is obviously different from other groups, and the root length of the bacterial liquid diluted by 600 times is 121.77% of that of the control group; stem growth: all had inhibitory effects, but there was no significant difference, and the inhibitory effect was the weakest at 600-fold dilution, which was 98.39% of the control.

TABLE 6 influence of Bacillus FJAT-47164 on the root length of mung bean seeds

In the above table, abcd represents significant difference (P < 0.05).

In a word, the bacterial suspension of the bacillus FJAT-47164 can not only improve the vitality of mung bean seeds, but also promote the rooting of mung bean sprouts. Therefore, in the seed germination stage, the bacterial suspension, i.e. the bacterial concentration of the bacillus FJAT-47164 diluted by 600-1200 times can be used⁵cfu·mL^-1Soaking the seeds for 6-8 hours, covering with wet gauze, accelerating germination at 25-28 deg.C for 2-3 days to promote rooting and germination of the seeds, sowing when 1/2-2/3 seeds are exposed, and using seedling-raising soil or seedling-raising block as matrix.

In conclusion, the bacillus FJAT-47164 can not only inhibit phytopathogens, but also promote plant rooting. In the germination stage of tomato, watermelon and other seeds, the seeds can be soaked by the bacterial suspension of bacillus FJAT-47164 with a certain concentration to promote the rooting and germination of the seeds, and the bacteriostatic solution is conveyed to leaves through the root system, and the blight and the like can be resisted in the growth stage of tomato, watermelon and other plants.

It should be noted that, although the above embodiments have been described herein, the invention is not limited thereto. Therefore, based on the innovative concepts of the present invention, the technical solutions of the present invention can be directly or indirectly applied to other related technical fields by making changes and modifications to the embodiments described herein, or by using equivalent structures or equivalent processes performed in the content of the present specification and the attached drawings, which are included in the scope of the present invention.

Claims

1. A Bacillus that antagonizes phytopathogens and root-growth promoting bacteria, comprising: the Bacillus is Bacillus velezensis FJAT-47164 with the scientific name of Bacillus velezensis FJAT-47164, is preserved in the common microorganism center of China Committee for culture Collection of microorganisms, has the preservation number of CGMCC NO.15948, has the preservation date of 2018, 6 and 19 days, and has the preservation address of the institute of microorganisms of China academy of sciences, Beijing, China.

2. Use of the antagonistic phytopathogen and root promoting bacillus of claim 1 for antagonising a phytopathogen.

3. Use of an antagonistic phytopathogen and a root promoting bacillus according to claim 2 for antagonising a phytopathogen, wherein: the bacillus is prepared into an antibacterial solution, and the antibacterial solution is irrigated to plant seedling roots by a root irrigation method or sprayed to plant leaves or fruits.

4. Use of an antagonistic phytopathogen and a root promoting bacillus according to claim 3 for antagonising a phytopathogen, wherein: the preparation method of the bacteriostatic solution comprises the steps of inoculating the bacillus strain to a solid culture medium plate, selecting a single colony of a strain ring, inoculating the single colony of the strain ring to a corresponding liquid culture medium, and culturing at the constant temperature of 25-35 ℃ for 36-60 h; and (3) centrifuging the bacillus fermentation liquor, discarding the thallus, and taking the supernatant to obtain the antibacterial solution.

5. Use of the antagonistic phytopathogen and root promoting bacillus of claim 1 for promoting germination of plant seeds.

6. The use of a plant pathogenic bacterium antagonistic and root promoting bacillus according to claim 5 for promoting germination of plant seeds, characterized in that: soaking the bacillus strain suspension for 6-8h, accelerating germination at 25-28 deg.C for 2-3 days, and sowing when 1/2-2/3 seeds are exposed.

7. According toThe use of a plant pathogen antagonistic and root promoting bacillus of claim 6 for promoting germination of plant seeds, wherein: the preparation method of the bacillus bacterial suspension comprises the steps of inoculating bacillus strains on a solid culture medium flat plate, selecting a single bacterial colony with a bacterial ring, inoculating the single bacterial colony into a corresponding liquid culture medium, culturing at the constant temperature of 25-35 ℃ for 36-60h, and diluting the cultured bacterial liquid until the bacterial concentration is 1-4 multiplied by 10⁵cfu·mL^-1And (4) finishing.