CN113249266B

CN113249266B - Bacillus subtilis capable of efficiently dissolving phosphorus and promoting sugarcane germination and application thereof

Info

Publication number: CN113249266B
Application number: CN202110692321.2A
Authority: CN
Inventors: 李富生; 狄义宁; 谢林艳; 何丽莲; 刘鲁峰
Original assignee: Yunnan Agricultural University
Current assignee: Yunnan Agricultural University
Priority date: 2021-06-22
Filing date: 2021-06-22
Publication date: 2023-02-03
Anticipated expiration: 2041-06-22
Also published as: CN113249266A

Abstract

The invention discloses bacillus subtilis and application thereof, and belongs to the technical field of microorganisms. The strain is preserved in Guangdong province microorganism strain preservation center in 2019, 7 months and 15 days, and the preservation number is GDMCC NO:60727 (a) of a liquid crystal, the preservation address is the microbiological research institute of Guangdong province of No. 59 building and No. 5 building of Mieli Zhou 100 college in Guangzhou city. The bacillus subtilis disclosed by the invention is an endophyte separated from sugarcane, and the strain or a metabolite thereof has a better phosphorus and potassium dissolving effect, is beneficial to improving the structure of soil nutrient substances, can also obviously improve the germination rate of the sugarcane or other crops, and is beneficial to improving the growth promoting effect.

Description

Bacillus subtilis capable of efficiently dissolving phosphorus and promoting sugarcane germination and application thereof

Technical Field

The invention relates to the field of microorganisms, in particular to bacillus subtilis capable of efficiently dissolving phosphorus and promoting sugarcane germination and application thereof.

Background

Endophytes refer to a class of microorganisms that can survive from healthy plant living tissue without causing significant disease in the host plant, and are a rich source of microorganisms, mainly including bacteria, fungi, and actinomycetes. Therefore, the isolation of endophytes from plant biopsies has been reported. However, different plants or different species isolated from the same plant have different functions or can produce different kinds of metabolites, and thus can be effectively utilized according to different requirements.

With the gradual increase of the dependence degree of people on chemical fertilizers, the plant growth is promoted, the yield is improved, and meanwhile, a plurality of side effects can be brought, such as: the soil is acidified and hardened, and the nutrient substances are low, so that the soil is not beneficial to plant absorption and utilization; the content of nitrogen and phosphorus elements in water is increased, and eutrophication of water bodies such as rivers, lakes and the like is promoted, so that excessive propagation of algae, water quality deterioration, massive death of fishes, namely other aquatic organisms and the like are caused; soil microorganisms die, microbial structure systems change, and dominant strains of a plurality of beneficial microorganisms become secondary strains, so that crop diseases are easily caused. The use of biological bacterial manure is an important way for improving soil structure or promoting plants to absorb and utilize nutrients in soil in recent years. However, sugar cane is an important sugar crop and energy crop, a large number of endophytes exist in the sugar cane, and related reports exist for separating endophytes such as bacillus subtilis from sugar cane and applying the endophytes to the aspects such as phosphorus dissolving, rooting promoting and the like, but the phosphorus dissolving effect is poor, and related reports that related plant bacillus subtilis can store bud growth do not exist at present. The invention separates a new bacillus subtilis strain from the sugarcane, has the advantages of high-efficiency phosphorus dissolution, obvious improvement of the sprouting rate of the sugarcane seedling stems and the like, and has important significance for solving a series of problems caused by excessive dependence on chemical fertilizers at present.

Disclosure of Invention

The invention aims to solve the problems in the prior art and provides the bacillus subtilis with high phosphorus dissolution efficiency and the effect of promoting the germination of the sugarcane and the application thereof.

In order to achieve the purpose, the invention provides the following scheme:

the invention provides a Bacillus subtilis which is preserved in Guangdong province microorganism strain preservation center in 7-15 days in 2019, wherein the preservation number is GDMCC NO:60727 the weight ratio of the mixture to the liquid, the preservation address is Guangzhou microbial research institute of Guangzhou province, no. 59 building, no. 5 building, of Mieli Dazhou, no. 100, guangzhou province.

The invention also provides a microbial inoculum which comprises the bacillus subtilis or a metabolite thereof.

The invention also provides application of the bacillus subtilis or the metabolite thereof in soil improvement.

Preferably, the bacillus subtilis or the metabolite thereof is applied to the improvement of the effect of dissolving phosphorus and potassium in soil, and the capability of dissolving organic phosphorus of the bacillus subtilis or the metabolite thereof is greater than the capability of dissolving inorganic phosphorus.

The invention also provides application of the bacillus subtilis or the metabolite of the bacillus subtilis in promoting improvement of single-shoot vigor and/or agronomic traits of plants.

Further, the single-shoot growth vigor of the plant includes but is not limited to germination rate, shoot length, root number, and root system weight;

the agronomic traits include, but are not limited to, plant height, stem thickness, fresh species, dry weight, chlorophyll, root activity, and plant nitrogen, phosphorus, and potassium.

Preferably, the plant comprises Brassica and Raphanus of Brassicaceae, beta and spinach of Chenopodiaceae, solanum of Solanaceae, cichorium of Asparagus lettuce of Compositae, amaranthus of Amaranthaceae, and Ipomoea of Convolvulaceae.

Further, brassica includes Brassica juncea, brassica campestris, brassica juncea, and Brassica juncea; raphanus includes Raphanus sativus seedling; the beet genus comprises beet core; spinach includes big leaf spinach; solanum includes Solanum nigrum L; the genus Lactuca includes Lactuca italica; amaranthaceae including herba Portulacae and Sijixiang semen Tritici Aestivi; the genus Ipomoea includes seeds of Spatholobus glauca.

The invention discloses the following technical effects:

the invention relates to bacillus subtilis endophyte separated from Yunnan sugarcane, which is found by experiments to have obvious influence on the growth of the germination rate, the bud length and the root length of a single-bud seedling of the sugarcane, and the germination rate can reach 100 percent; compared with a control group, the growth period is 14 days, the bud length can be improved by 220.9 percent, and the root length can be improved by 105.2 percent.

The bacterium can also decompose phosphorus sources from different sources, the capacity of decomposing organic phosphorus is greater than the capacity of decomposing inorganic phosphorus, and in addition, the bacterium has strong capacity of dissolving potassium elements, so that the closed-storage soluble phosphorus and potassium in soil are released and dissolved, the content of nitrogen, phosphorus and potassium in the soil is increased, the absorption of plants to nutrients in the soil is facilitated, the demand of plant growth can be met, and the bacterium has a good growth promoting effect. Therefore, the bacillus subtilis or the metabolite thereof disclosed by the invention has important functions and significance for developing microbial agents or bacterial fertilizers with plant growth promoting effects or soil improvement.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required in the embodiments will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 shows the phylogenetic tree of strain ScBS 1;

FIG. 2 shows the difference of sugarcane tissue culture seedlings after ScBS1 bacterial treatment;

FIG. 3 shows the growth promoting conditions of ScBS1 bacteria on single-bud seedlings of different varieties of sugarcane; a, a sugar cane cultivar Yue sugar 93-159, b, a sugar cane cultivar Yunnan sugar 11-728, c, a sugar cane cultivar Liucheng 09-182, d, a sugar cane cultivar Xintai sugar No. 22, e, a sugar cane cultivar Yunnan sugar 01-58, f, a sugar cane cultivar Gui sugar 11;

FIG. 4 shows the germination rates of different vegetable seeds after 24 hours under various bacteria liquid concentrations;

FIG. 5 shows the germination rates of different vegetable seeds after 72 hours under various bacteria liquid concentrations;

FIG. 6 is a graph showing the difference in fresh weight between vegetables; a, testing results of pot culture of the thick leaf mustard; b, pot culture test results of the green bone water spinach; c, pot culture test results of Italian lettuce; d. e and f are agronomic characters of the thick leaf mustard, the green bone water spinach and the Italian lettuce, such as plant height, root length, leaf width and leaf length;

FIG. 7 shows the characteristics of the culture of ScBS1.

Detailed Description

Reference will now be made in detail to various exemplary embodiments of the invention, the detailed description should not be construed as limiting the invention but as a more detailed description of certain aspects, features and embodiments of the invention.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Further, for numerical ranges in this disclosure, it is understood that each intervening value, between the upper and lower limit of that range, is also specifically disclosed. Every smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in a stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated herein by reference to disclose and describe the methods and/or materials in connection with which the documents are cited. In case of conflict with any incorporated document, the present specification will control.

It will be apparent to those skilled in the art that various modifications and variations can be made in the specific embodiments of the present disclosure without departing from the scope or spirit of the disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification. The description and examples are intended to be illustrative only.

Example 1

1. Experimental Material

Root tissue of 'sugarcane cultivar Yunzhan 99-91' in a sugarcane resource garden of Yunnan agricultural university.

2. Isolation and identification

Separating and purifying the sugarcane tissue by using an LB culture medium to obtain a strain named as ScBS1.

3. Observation of culture characteristics

When cultured in LB solid medium, the strain ScBS1 can be obviously observed in a flat plate after being cultured for 10h at 37 ℃, the center of the strain is convex, watery secretion is observed in the interior of the convex, the convex disappears after 24h, the strain is irregular and round in shape, the surface is not smooth, the edge is not flat, the strain is yellow and white, and the diameter of a bacterial colony is 0.3-1cm (as shown in figure 7).

4. Physiological and biochemical characteristic identification

The physiological and biochemical identification tests were carried out on the strains isolated as described above according to the identification method in the general handbook of identification of bacteria system (Dongxiu bead et al, general handbook of identification of bacteria system [ M ]. Beijing: scientific Press, 2001.), and the results are shown in Table 1.

TABLE 1 identification results of physiological and biochemical characteristics

5. And (3) selecting 1 strain single colony obtained by separation, inoculating the strain single colony to an LB liquid culture medium, culturing at 37 ℃ to logarithmic phase, taking a bacterium solution, centrifuging at 15000rpm for 15min, and collecting thalli. According to the extraction method of the bacterial DNA extraction kit of Tiangen (Beijing) Biotechnology limited company, the genome DNA of the thalli is extracted, PCR amplification is carried out by using a general bacterial specific primer, then sequence identification is carried out by a biochemical company, BLAST comparison is carried out in an NCBI database, the sequence of a strain with higher homology is selected, MEGA6 software is used for constructing a developmental tree, and the classification status of the strain is determined as shown in figure 1.

According to the culture characteristics, physiological and biochemical characteristics and sequence identification results, the exogenetic pseudomonas is taken as an exogenetic group, the amylolytic pseudomonas of the same genus is taken as an endo-group, and the ScBS1 and the model strain Bacillus subtilis strain BCRC 10255 ^T Clustering at the same branch shows that the separated strain ScBS1 belongs to the bacillus subtilis strain.

Example 2 Bacillus subtilis ScBS1 ability to dissolve phosphorus and potassium

1. Determination of phosphorus solubilizing ability

Inoculating the strain with Ca ₃ (PO ₄ ) ₂ In a liquid medium containing a poorly soluble phosphate as a substrate (poorly soluble phosphorus medium (NBRIP): glucose 10g/L, mgCl ₂ ·6H ₂ O 5.0g/L，MgSO ₄ ·H ₂ O 0.25g/L，KCl 0.2g/L，(NH ₄ ) ₂ SO ₄ 0.1g/L, adding the insoluble phosphate or the phosphate ore, adding distilled water to 1000mL, adjusting the pH to 7.0-7.5, adding the distilled water to 1000mL, and adding no agar in the liquid). By comparing with the blank control without inoculation, the content of soluble phosphorus is obviously increased after the inoculation of the bacillus subtilis ScBS1, the content of the soluble phosphorus is 39.40 +/-1.88 mg/L on the first day, 60.71 +/-5.50 on the third day, 73.79 +/-4.69 mg/L on the sixth day, and the content of the soluble phosphorus is the maximum (164.09 +/-4.94) mg/L on the tenth day. In culture solution using calcium phytate as substrateThe content of soluble phosphorus reaches the maximum in 10 days, the content of the soluble phosphorus is (840.61 +/-38.83) mg/L, the content of the soluble phosphorus is 180.07 +/-11.63 mg/L on the rest of days, the content of the soluble phosphorus is 409.05 +/-31.41 mg/L on the third day, and the content of the soluble phosphorus is 639.02 +/-31.29 mg/L on the sixth day, so that the bacillus subtilis ScBS1 respectively has organophosphorus dissolved phosphorus with different phosphorus sources>Inorganic phosphorus, and it was also observed that the pH of the culture solution started to decrease after inoculation of the bacteria and was a period of time during which the soluble phosphorus was the largest before and after the lowest pH, and as the pH was increased subsequently, the soluble phosphorus content decreased, and it was thus hypothesized that the phosphorus-solubilizing mechanism was involved in the production of organic acids.

2. Determination of Potassium solubilizing ability

Test materials: 22 parts of neotame, 11-728 parts of Yunnan sugar, 93-159 parts of Guangdong sugar, 11 parts of bay sugar, 01-58 parts of Yunnan sugar and 03-182 parts of willow city, 6 sugarcane varieties (potted growth 70d, sugarcane seedlings). Original soil and soil without Bacillus subtilis ScBS1 are used as controls.

The results of measuring the change of nutrient elements before and after soil planting are shown in table 2.

TABLE 2 modification of conventional 8 items of sugarcane soil by Bacillus subtilis ScBS1

Table 2 shows that 8 conventional items of soil are significantly changed by inoculating bacillus subtilis ScBS1, and original soil represents the soil nutrient level before planting, and it can be seen from table 2 that after the bacillus subtilis ScBS1 is applied, the nitrogen, phosphorus and potassium contents in soil are well changed, especially potassium element is changed, but a large amount of plant soluble phosphorus and potassium become closed storage state due to soil acidification and the like, and plants cannot directly absorb and utilize the plant soluble phosphorus and potassium, and after the bacillus subtilis ScBS1 is applied, closed storage state resources in soil are released and dissolved, the internal nitrogen, phosphorus and potassium contents are increased, sufficient potassium ensures the growth of plants, and the material also meets the biological functions of microbial fertilizers. The test also measures nutrient elements and phenotype in sugarcane seedlings in potted plants, and table 3 shows the detection result of the nitrogen, phosphorus and potassium contents of the plants, and the result shows that the bacterial strain ScBS1 can promote the plants to absorb nutrients. Table 4 shows the change of the physiological index and appearance form of the sugarcane seedlings among different treatment groups after the ScBS1 strain is inoculated, in table 4, the ScBS1 strain obviously improves the photosynthetic rate of the plant and the phenotypic index related to biomass yield, which shows that the bacillus subtilis ScBS1 has a growth promoting effect on different varieties of sugarcane, and among the rest agronomic characters and physiological indexes, the bacillus subtilis ScBS1 treatment group is superior to the control group, and part of the parameters reach significant differences.

TABLE 3 variation of plant Nitrogen, phosphorus and Potassium after inoculation of ScBS1 Strain

TABLE 4 phenotypic changes of plants after inoculation with ScBS1 Strain

3. Measurement of physiological and biochemical indexes in tissue culture seedlings

The propagation and the culture of the sterile virus-free seedlings of the sugarcane are carried out at the same period of the test, the propagation and the culture are divided into the potted culture of tissue culture seedlings and the greenhouse culture of test-tube seedlings, and the ScBS1 bacterial liquid 10 is carried out ⁶ Inoculation with cfu/mL gradient, as can be seen in FIG. 2 and Table 5: the treated group has developed root system compared with the control group, has higher root system activity, and is 33.6 percent higher than CK treated by ScBS1 bacterial liquid; the glutamine synthetase and the glutamate synthetase in the treated group are higher than the control and are respectively improved by 33.98 percent and 19.32 percent in the determination of the enzyme activity related to nitrogen metabolism, which shows that the ScBS1 strain can promote the accumulation of nitrogen elements of sugarcane seedlings and has stronger activityNitrogen metabolism activity; the rooting performance of the sugarcane seedlings in the test-tube plantlets is obvious, the root length and the root activity are obviously increased compared with a control (figure 2), external interference and pollution of other mixed bacteria are avoided by single test-tube inoculation, and the test tube inoculation method has a stronger persuasive basis compared with a pot experiment.

TABLE 5 influence of ScBS1 strains on agronomic traits and physiological and biochemical indicators of test-tube plantlets

Example 3 growth promoting Effect of Bacillus subtilis ScBS1 on sugarcane and other crops

1. Experimental Material

Sugarcane seedlings and seed stems

2. Preparation of bacterial liquid

And (3) bacterial culture: inoculating 10 μ L of Bacillus subtilis ScBS1 stock solution into sterilized liquid LB culture medium in a superstmeus platform irradiated with ultraviolet rays for 30min, sealing the bottle mouth, and placing in a shaker at 37 deg.C and 120rpm/min for continuous propagation for 72h.

Preparing a bacterial inoculation liquid: culturing the bacterial liquid at 37 deg.C for 72h, centrifuging at 12000rpm/8min in a high speed centrifuge to obtain culture medium-removed thallus, resuspending in sterile clean water in an aseptic clean bench, counting by dilution coating flat plate method, determining bacterial liquid thallus number per unit volume, and configuring concentration of 10 ⁵ cfu/ml、10 ⁶ cfu/ml、10 ⁷ cfu/ml resuspension is ready for use.

3. Growth promoting effect on sugarcane

The method comprises the steps of selecting sugarcane single-bud stems with relatively uniform size and length, soaking and detoxifying the sugarcane single-bud stems by 2% lime water, soaking the sugarcane single-bud stems in the bacillus subtilis ScBS1 bacterial suspension for 1h, soaking the sugarcane single-bud stems in clear water as a control, accelerating germination for 5d, observing the growth vigor of the sugarcane single-bud stems, and measuring the bud length, the root number and the root weight of the sugarcane single-bud stems. The treatment is performed by CK (clear water) and Bacillus subtilis ScBS1 bacterial liquid treatment, and the bacterial content is controlled to be 1 multiplied by 10 ⁷ The application is carried out by a cfu/g root irrigation method, each treatment is repeated for 6 times, and 12 seedlings are obtained in total. After the character difference appears, the plant height, the stem thickness and the fresh species are measured,dry weight, chlorophyll, root activity, agronomic characters and physicochemical properties of plants such as nitrogen, phosphorus and potassium, and the like.

TABLE 6 influence of different B9 concentrations on the germination percentage of sugarcane seedlings

As can be seen from Table 6, the germination rate of the sugarcane single bud seedling bud treated by inoculating the ScBS1 bacterial liquid is obviously higher than that of the sugarcane single bud seedling bud treated by clear water, and the inoculation concentration of the sugarcane single bud seedling bud treated by the ScBS1 bacterial liquid is 10 in the three treatments ⁶ The growth promotion effect of cfu/mL is most obvious, and the germination rate is improved to 100 percent and 10 percent ⁷ The growth promoting effect of cfu/mL is low, therefore 10 ⁶ cfu/mL is the most suitable concentration of the germination medium liquid. The bacillus subtilis ScBS1 is separated from sugarcane and can be mutually beneficial to the sugarcane, and can quickly enter a plant body and be utilized by the plant, so that the sugarcane single-bud seedling can germinate well under the action of endophyte with proper concentration. 10 ⁷ Although the cfu/mL contrast blank has a growth promoting effect, the growth promoting effect is not obvious, the germination rate is increased by 2% compared with the blank, and the germination rate increasing effect is lower.

TABLE 7 Effect of ScBS1 inoculation on shoot growth of sugarcane Single-bud seed

TABLE 8 Effect on sugarcane Single-bud Stem seed roots after ScBS1 inoculation

Note: the letter Aa after the data in tables 7 and 8 indicates that p.ltoreq.0.01 is very significantly different. A represents that the difference of p is less than or equal to 0.05, and b represents that the difference of p is more than or equal to 0.05 is not significant, and the following is the same.

As can be seen from tables 7 and 8, the ScBS1 bacterial liquid with different concentrations has different effects on the growth of the single bud and the root of the sugarcane. At 10 ⁵ -10 ⁶ The root length and the bud length of the cfu/mL concentration are better than those of other cfu/mL concentrationsTreatment of, wherein at 10 ⁶ The growth speed of roots and buds of the sugarcane single bud seedlings under the concentration of cfu/mL is obviously improved, the root length is improved by 146.8 percent, 105.2 percent and 78.5 percent compared with the control, and the bud length is respectively improved by 196 percent, 220.9 percent and-38.5 percent compared with the control at the same time of 7d,14d and 21d, so 10 percent ⁶ cfu/mL is the optimum sugarcane growth concentration, 10 ⁷ cfu/mL is rather inhibited, at the same time as 7d,14d and 21d, the root length is reduced by 41.1%,11.1% and 11.38% respectively compared with the control, and the bud length is reduced by 65.5%,37.1% and 38.4% respectively compared with the control, so the concentration is 10 ⁷ cfu/mL and above are not suitable for sugarcane growth.

In addition, also at 10 ⁶ The growth promoting effect on different varieties of sugarcane is measured under the cfu/mL concentration, the results are shown in figure 3 and table 9, and the results show that the ScBS1 bacterial liquid has obvious growth promoting effect on the root growth and the bud growth of different varieties and are consistent with the results.

TABLE 9 growth promotion of ScBS1 on single-bud seedlings of different varieties of sugarcane

4. Growth promoting effect on other crops

The experiment is carried out by using the following 6 common fruits and vegetables of 8 genera and 12 species, and specifically comprises the following steps: brassica includes Brassica juncea, brassica campestris, brassica juncea, and Brassica juncea; raphanus comprises Raphanus sativus seedling; the beet genus comprises beet core; spinach includes big leaf spinach; solanum includes Solanum nigrum L; the genus Lactuca includes Lactuca italica; amaranthaceae including herba Portulacae and Sijixiang semen Tritici Aestivi; the sweet potato comprises green bone swamp cabbage seed.

The fruit and vegetable seeds are soaked in bacterial liquid suspensions of ScBS1 with different concentrations, and the treatment concentrations are selected from sterile CK control and 5.0 (lg 10) cfu.mL ^-1 、6.0(lg10)cfu·mL ^-1 、7.0(lg10)cfu·mL ^-1 Counting the germination vigor of each species in 1-3 days, wherein the number of seeds in each treatment group is more than 20, the seeds are arranged into three groups in parallel and are respectively placed at 600umol.s.m ² Culturing in a light incubator at 25 ℃ at an interval of 12h day and night. If the water in the process evaporates, sterile distilled water is added to the initial seed dip volume.

As can be seen from FIG. 4, the germination rates of Brassica campestris, brassica juncea, brassica campestris and Italian lettuce were increased significantly in 24h after the treatment of 12 kinds of vegetable seeds, and were 5.0 (lg 10) cfu. ML ^-1 The increase is 72.69%,71.97%, 51.98% and 41.38% respectively relative to the sterile treatment of clear water; 6.0 (lg 10) cfu. ML ^-1 In the concentration, the differences of the mustard, radish seedlings and Italian lettuce in the same four seasons are obvious and are respectively increased by 59.49 percent, 13.89 percent and 48.48 percent. In the treatment using the bacterial liquid, the bacterial liquid concentrations of different seeds are found to be specific to the bacterial liquid concentrations, the concentration of the bacterial liquid ScBS1 for optimally promoting the four-season mustard, red-leaf pakchoi, chinese cabbage heart and seeds is 5 (lg 10) cfu/mL, and the concentration of the bacterial liquid ScBS1 for optimally promoting the four-season mustard, italian lettuce, green bone water spinach and seeds is 6.0 (lg 10) cfu.mL ^-1 The optimal bacterial liquid concentration for the crude leaf mustard is 7.0 (lg 10) cfu.mL ^-1 For amaranthus grandiflorus, the germination rate of the clear water control is higher than that of the bacterial liquid treatment, the effect of promoting growth of the ScBS1 bacteria on the initial germination of amaranthus sativus seeds is not obvious, and the experimental interestingness is that the solanum violaceum is 6.0 (lg 10) cfu.mL of the ScBS1 bacteria ^-1 The seed soaking in the concentration of 24h is firstly germinated and is superior to other treatments, the phenomenon means that the purple red eggplant is adaptive to the external environment earlier, the growth cycle is prolonged, and the quality of crops is guessed to be improved.

Obviously, after 3 days, the germination rate of the seeds of each treatment group is over 60 percent, and 6 (lg 10) cfu & mL ^-1 The concentration of the Chinese kale, the Sijixiangyou wheat and the green bone water spinach is 70.23 percent, 34.82 percent and 22.94 percent which are different. We found that after 72 hours, compared to 24h of 6 (lg 10) cfu. ML ^-1 The concentration is the optimal growth promoting concentration, and the concentration is 7 (lg 10) cfu & mL ^-1 The treatment gradually shows advantages, wherein the larger ones are mustard, cabbage, and green bone water spinach. The growth rate is 18.96%, 67.46% and 21.24%. Part of the species such as Siji sesame oil wheat still shows 7 (lg 10) cfu.mL ^-1 High concentration bacterial liquid is not suitable for the situation. From the 72h results in FIG. 5, it was found that the difference in germination rate growthThe seed germination rate is improved indeed by the bacterial liquid treatment, and the condition of broad spectrum application of the ScBS1 strain in other vegetable species is proved, so that the research has important reference value in enlarging the application range of the ScBS1 strain and researching strain-specific colonization contrast experiments.

The experiment selects the good growth of the Roughage kale, italian lettuce and swamp cabbage as the research objects, the seedlings are transferred to pot culture after the seeds are soaked in the bacterial liquid, the result is shown in figure 6 under the condition of 25d culture, the growth of the three vegetables still presents difference between different treatments, and for the Roughage kale, the variety still presents 5.0 (lg 10) cfu.mL ^-1 The growth condition showed better under the bacterial liquid concentration, 5.0 (lg 10) cfu.mL ^-1 The height of the thick leaf kalimeris indica is 9.90 +/-1.54 cm under the concentration, the height is increased by 18.69 percent compared with the aseptic contrast, the root length is increased by 17.09 percent, the index of the leaf width and the leaf length is also obviously higher than the contrast of 25.1 percent and 21.84 percent, the more optimal leaf width and the leaf length represents a larger photosynthesis area, and the potential of improving the quality and the growth vigor is better; in the green bone water spinach, 5.0 (lg 10) cfu. ML ^-1 The treatment group is still the best growth treatment group, and the difference of root growth is obviously observed under the concentration gradient through b and e, and in the comparison process, the difference is found to be 5.0 (lg 10) cfu & mL ^-1 The lower root length is 15.36 +/-0.19 cm, the lower root length is increased by 37.70 percent compared with a sterile control, the indexes of edible parts such as plant height and the like are also obviously higher than the control, the plant height and the like are relatively increased by 12.57 percent, and the fresh weight index on the ground in figure 5 is increased by 34.98 percent. In addition, 5.0 (lg 10) cfu. ML was removed ^-1 All other treatment groups were also above the sterile control. The increase of the edible part indicates that the crop yield is increased, and the growth promoting effect of the ScBS1 strain in the green bone water spinach is obvious; in Italian lettuce, 6.0 (lg 10) cfu. ML ^-1 The indexes of plant height, leaf length and leaf width of the treatment group are 9.642 +/-1.52, 3.38 +/-0.36 and 2.7 +/-0.38 cm, the indexes are increased by 16.10 percent, 25.44 percent and 41.48 percent compared with the control, the fresh weight on the ground is increased by 57.6 percent, and the optimal treatment group for roots is 5.0 (lg 10) cfu.mL ^-1 It is hypothesized that at this concentration the auxin concentration adapts to the growth of the Italian lettuce roots, and that too high a concentration inhibits root growth. The high-concentration bacteria liquid has more solidNitrogen, etc. and has the capacity of raising the indexes of aerial part. The improvement of the fresh weight of the underground part can be expressed as the improvement of the stress resistance of the seedling plant and has certain tolerance capability to stress such as drought and the like.

The above-described embodiments are only intended to illustrate the preferred embodiments of the present invention, and not to limit the scope of the present invention, and various modifications and improvements made to the technical solution of the present invention by those skilled in the art without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. Bacillus subtilis (B.subtilis)Bacillus subtilis) The method is characterized in that the accession number is GDMCC NO:60727.

2. a bacterial agent comprising the Bacillus subtilis according to claim 1.

3. A bacterial fertilizer comprising the bacillus subtilis of claim 1.

4. Use of the bacillus subtilis of claim 1 for improving soil.

5. The use according to claim 4 for improving the phosphorus dissolving effect of soil.

6. Use of bacillus subtilis according to claim 1 for promoting single shoot vigour and/or agronomic trait improvement in plants, in particular: promoting the germination rates of red-leaf pakchoi, leaf mustard in the four seasons, sweet cabbage, radish seedlings, italian lettuce, green-bone water spinach and purple-red long eggplant, promoting the leaf width and the leaf length of the cabbage mustard, promoting the root length, the plant height and the fresh weight of the green-bone water spinach, and promoting the plant height, the leaf length, the leaf width and the fresh weight of the Italian lettuce; the increase of the nitrogen, phosphorus and potassium contents of the leaves and roots of the sugarcane is promoted, and the number, width, fresh weight, stem thickness and stem length of the leaves are increased; the plant height, root length and root activity of the sugarcane are promoted, and the increase of glutamine synthetase, glutamate synthetase and chlorophyll is promoted; promoting the germination rate of the sugarcane, the growth of single-bud seedlings and the growth of single-bud stems and roots.