KR102599254B1 - Composition for promoting plant growth comprising microbial agent comprising a strain of Paenibacillus polymyxa MDBDO or a culture thereof, and method for manufacturing the same - Google Patents

Abstract

The present invention relates to a composition for promoting plant growth containing a microbial agent containing a Paenibacillus polymyxa MDBDO strain or a culture medium thereof, and a method for producing the same. The present invention relates to a composition for promoting plant growth and a method for producing the same, and confirms the plant growth promoting function of the Paenibacillus polymyxa MDBDO strain. And, as a result of treating strawberries, which are representative facility crops, and soybeans, which are field crops, either alone or mixed with chemical fertilizers, it was confirmed that they had growth promotion and yield increase effects that were similar to or far superior to chemical fertilizers. In addition, it was confirmed that the decrease in total chlorophyll content of crop leaves caused by chemical fertilizers could also be resolved.
Therefore, the agricultural microbial fertilizer completed according to the present invention can solve environmental problems and problems such as salt accumulation in the soil as an effective substitute or reducer for chemical fertilizers. In addition, it can promote crop growth, advance crop harvest time, and contribute to farm income by increasing yield.

Description

Composition for promoting plant growth comprising microbial agent comprising a strain of Paenibacillus polymyxa MDBDO or a culture thereof, and method for producing the same manufacturing the same}

The present invention relates to a composition for promoting plant growth containing a microbial agent containing Paenibacillus polymyxa MDBDO strain or a culture medium thereof, and a method for producing the same. More specifically, it relates to a composition for promoting plant growth and a method for producing the same, and more specifically, to a composition for promoting plant growth and a method for producing the same. This relates to a technology that induces the effect of promoting plant growth and increasing yield when treated alone or mixed with commercial chemical fertilizers using the culture medium of the Myxa MDBDO strain.

Problems arising from excessive use of chemical fertilizers continue to be raised. This is causing adverse effects on almost all aspects of the environment, including acidification of soil, pollution of groundwater, freshwater, and seawater, as well as greenhouse gases caused by nitrous oxide emitted from agricultural lands. In addition, leaching of trace elements (zinc, magnesium, aluminum, etc.) in the soil leads to poor crop growth due to antagonism of nutrient absorption in plants, causing direct economic loss to farmers. Various fertilizers, such as organic fertilizers and by-product fertilizers, have been developed to replace them, but they have limitations as problems such as ammonia generation during the production process and inconvenience to farmers due to bad odors are raised.

As a result, research and development on microbial fertilizers is being actively conducted as an improvement measure. Through the action of various enzymes, microorganisms can supply plants with limiting factors in the soil, such as nitrogen, potassium, and phosphorus provided by chemical fertilizers, as well as insoluble minerals such as zinc, magnesium, silicic acid, and iron, and use these to produce auxin, a plant growth-promoting hormone. (IAA, IBA), gibberellin, ACC deaminase that interferes with the production of ethylene, and cytokines are produced and provided to plants to promote growth, strengthen the plant immune system, and enhance tolerance to environmental stress. It is known to be provided to crops.

Zinc is a nutrient required in trace amounts by plants, but when it is deficient, crop growth is slowed and yields are reduced. This phenomenon has been reported to be caused by yellowing or smaller leaves, spikelet sterility, impaired root development or water utilization, and pollen formation. Additionally, zinc is known to be involved in the synthesis pathway of IAA, a plant growth hormone, and carbohydrate synthesis. However, zinc exists mostly in the soil in a form that is insoluble or difficult to absorb into plants, and excessive use of phosphate fertilizers is also known to induce zinc deficiency.

Conventional technologies related to this include a new strain of Lactococcus lactis LKS49 with insoluble salt solubilization activity and antifungal activity, a novel Methylobacterium fugisawaens CBMB 20 strain and a plant growth promotion method using the same, and a new microorganism, Bacillus nematotocyta. CJ13-2 and soil microbial fertilizer containing the same, soil microbial preparation and livestock manure and microbial fertilizer containing the same, a new salt-tolerant Halomonas genus strain with excellent organic matter decomposition ability, a coastal landfill soil conditioner containing the same, and a method for promoting plant growth using the same, Microstroma Philoplanum AmE-3 strain and its uses, Azospirillum Brasilens CW301, a new strain with nitrogen-fixing ability and crop growth promotion effects, biofertilizer using it, and method for manufacturing the same.

Recently, research results have been reported showing that 2R,3R-butanediol, a volatile substance produced by microorganisms, triggers the proliferation of microorganisms in the soil rhizosphere of plants, enhances induced immunity of plants, and promotes plant growth.

In this regard, patents have been registered for butanediol extracted from the Enterobacter genus in the United States, Japan, China, and Europe, and methods for increasing drought and high salt tolerance of plants using Pseudomonas chlororaphis 06 strain and the resulting plants , a composition for controlling plant diseases containing 2,3-butanediol using a mixture of isomers of separated and purified 2,3-butanediol, etc.

However, the strains used above have limitations in industrialization due to their pathogenicity. Therefore, in order to produce 2R,3R-butanediol, which is used as a bioactive material, the invention of various microorganisms that are GRAS (Generally Recognized As Safe) is essential.

Conventional technologies using Bacillus, a representative GRAS microorganism, include a novel butane diol-producing microorganism, a method for producing butane diol using the same, a novel Pennybacillus polymyxa mutant strain MDBDO, and its uses. In addition, there are reports that mass production of 2,3-butanediol has been carried out in Bacillus subtilis, but there are few domestic patents that show the effect of mass production of 2,3-butanediol in promoting actual crop growth.

As described above, as research and inventions on various soil improvement abilities of microorganisms have been actively conducted, microbial strains and materials have been developed using nitrogen fixation ability, ammonification, solubilization of insoluble nutrients, and plant growth promoting hormones and substances. Recently, research on plant growth using volatile substances caused by microorganisms has been actively conducted around the world, so there is an urgent need to secure microorganisms that produce volatile plant growth promoting substances. In addition, to the extent that it is used as a biologically active material, materials produced by microorganisms with guaranteed stability can be said to be more valuable.

Although there are a variety of microbial fertilizers already available, the problem that they are not widely used in farms is also a problem that must be solved. In a situation where dependence on chemical fertilizers is very high, changing existing effective fertilization methods at once can be directly related to the income of farmers, making it difficult to actually introduce microbial fertilizers. Therefore, reducing the amount of chemical fertilizers processed and inventing methods for processing microbial fertilizers are also necessary to reduce the side effects caused by the use of chemical fertilizers and increase accessibility to the use of microbial fertilizers.

Accordingly, the present inventors developed a Paenibacillus polymyxa MDBDO strain and its culture solution that solubilizes insoluble nutrients and produces D-2,3-butanediol (D-2,3-BDO), a plant growth-promoting hormone and growth-promoting substance. It was confirmed that when provided as a microbial fertilizer, improvements in soil environment and environmental problems can be expected due to growth enhancement, increased yield, and reduction of chemical fertilizers.

Accordingly, the purpose of the present invention is to provide a composition for promoting plant growth containing a microbial agent containing the Pennybacillus polymyxa MDBDO strain deposited under the accession number KCTC14179BP, its culture medium, or a fraction of its culture medium.

Another object of the present invention is to provide a method for producing a composition for promoting plant growth, which includes a culturing step of preparing a culture medium by culturing the Pennybacillus polymyxa MDBDO strain deposited under accession number KCTC14179BP.

Another object of the present invention is to spray or immerse plants or plant seeds with a composition for promoting plant growth containing a microbial agent containing the Pennybacillus polymyxa MDBDO strain deposited under accession number KCTC14179BP, its culture medium, or a fraction of its culture medium. Alternatively, a method for promoting plant growth comprising a treatment step of irrigation is provided.

The present invention relates to a composition for promoting plant growth containing a microbial agent containing Paenibacillus polymyxa MDBDO strain or a culture medium thereof, and a method for producing the same. Paenibacillus polymyxa deposited under accession number KCTC14179BP according to the present invention. The culture medium of the Myxa MDBDO strain represents a technology that induces the effect of promoting plant growth and increasing yield when treated alone or mixed with commercial chemical fertilizers.

The present inventors confirmed the solubilization ability of insoluble nutrients and the IAA production ability of the Pennybacillus polymyxa MDBDO strain (Accession number: KCTC14179BP) producing D-2,3-butanediol (D-2,3-BDO). Furthermore, , the present invention was completed by confirming the promotion of crop growth and increase in productivity by applying this alone or in combination with chemical fertilizers in small field and cultivation experiments of crops grown in facilities.

Hereinafter, the present invention will be described in more detail.

One aspect of the present invention is a composition for promoting plant growth comprising a microbial agent containing the Pennybacillus polymyxa MDBDO strain deposited under accession number KCTC14179BP, its culture medium, or a fraction of its culture medium.

In ^the present invention, ^the microbial ^agent may contain the Pennybacillus polymyxa MDBDO strain at a concentration ^of 1 ^{ml , 1 _ _ _ _ _ cfu / ml , 1 _ _ 10 8 cfu / ml , 1 _ It may be} included at ^a concentration ^of 1 It may be done, but it is not limited to this.

In the present invention, the culture medium contains at least one selected from the group consisting of IAA (indole acetic acid), IBA (Indole 3-butyric acid), and D-2,3-butanediol (D-2,3-BDO). It may be done, but it is not limited to this.

In the present invention, the composition additionally contains a chemical fertilizer containing at least one selected from the group consisting of nitrogen, phosphorus, potassium, magnesium, and boron. It may be, but is not limited to this.

In the present invention, the chemical fertilizer may be diluted to a concentration of 0.01 to 100 g/L, preferably 0.01 to 50 g/L, 0.01 to 20 g/L, 0.01 to 10 g/L, 0.01 to 5 g. /L, 0.01 to 2 g/L, 0.01 to 1 g/L, 0.1 to 100 g/L, 0.1 to 50 g/L, 0.1 to 20 g/L, 0.1 to 10 g/L, 0.1 to 5 g/ L, 0.1 to 2 g/L, 0.1 to 1 g/L, 1 to 100 g/L, 1 to 50 g/L, 1 to 20 g/L, 1 to 10 g/L, or 1 to 5 g/L It may be diluted to a concentration of L, for example, to a concentration of 1 to 2 g/L, but is not limited thereto.

The composition may contain a microbial agent and a chemical fertilizer in a volume ratio of 80:20 to 20:80, preferably 80:20 to 30:70, 80:20 to 40:60, and 80:20 to 50: 50, 70:30 to 20:80, 70:30 to 30:70, 70:30 to 40:60, 70:30 to 50:50, 60:40 to 20:80, 60:40 to 30:70, It may be included in a volume ratio of 60:40 to 40:60, 60:40 to 50:50, 50:50 to 20:80, or 50:50 to 30:70, for example, 50:50 to 40. It may be included in a volume ratio of :60, but is not limited to this.

The composition may be used individually, mixed at the time of application, or used in a premixed form, but is limited thereto. It doesn't work.

In the present invention, the plant may be soybean or strawberry, but is not limited thereto.

Another aspect of the present invention is a method for producing a composition for promoting plant growth, comprising a culturing step of preparing a culture medium by culturing the Pennybacillus polymyxa MDBDO strain deposited under accession number KCTC14179BP.

In the present invention, the culturing step may be performed for 24 to 48 hours at a temperature of 25 to 45 ° C. and a pH of 4.5 to 7.5.

Preferably, the culturing step is performed at 25 to 42°C, 25 to 40°C, 25 to 38°C, 30 to 45°C, 30 to 42°C, 30 to 40°C, 30 to 38°C, 35 to 45°C, 35 to 42°C. ℃, or may be performed at a temperature of 35 to 40℃, for example, may be performed at a temperature of 35 to 38℃, but is not limited thereto.

Preferably, the culturing step is performed under pH conditions of 4.5 to 7.0, 4.5 to 6.5, 4.5 to 6.0, 5.0 to 7.0, 5.0 to 6.5, 5.0 to 6.0, 5.5 to 7.0, 5.5 to 6.5, 5.5 to 6.0, or 6.0 to 7.0. It may be performed at, for example, pH conditions of 6.0 to 6.5, but is not limited thereto.

Preferably, the culturing step is 24 to 42 hours, 24 to 38 hours, 28 to 48 hours, 28 to 42 hours, 28 to 38 hours, 32 to 48 hours, 32 to 42 hours, 32 to 38 hours, 36 to 48 hours. hours, or may be performed for 36 to 42 hours, for example, may be performed for 36 to 38 hours, but are not limited thereto.

The culturing step may be performed under culture conditions containing glucose as a carbon source.

In the present invention, the method includes a microbial preparation comprising the strain obtained in the culturing step, its culture medium, or a fraction of the culture medium; and at least one selected from the group consisting of nitrogen, phosphoric acid, potassium, magnesium, and boron. It may additionally include a mixing step of adding chemical fertilizer.

In the present invention, the chemical fertilizer may be diluted to a concentration of 0.01 to 100 g/L, preferably 0.01 to 50 g/L, 0.01 to 20 g/L, 0.01 to 10 g/L, 0.01 to 5 g. /L, 0.01 to 2 g/L, 0.01 to 1 g/L, 0.1 to 100 g/L, 0.1 to 50 g/L, 0.1 to 20 g/L, 0.1 to 10 g/L, 0.1 to 5 g/ L, 0.1 to 2 g/L, 0.1 to 1 g/L, 1 to 100 g/L, 1 to 50 g/L, 1 to 20 g/L, 1 to 10 g/L, or 1 to 5 g/L It may be diluted to a concentration of L, for example, to a concentration of 1 to 2 g/L, but is not limited thereto.

The composition may contain a microbial agent and a chemical fertilizer in a volume ratio of 80:20 to 20:80, preferably 80:20 to 30:70, 80:20 to 40:60, and 80:20 to 50: 50, 70:30 to 20:80, 70:30 to 30:70, 70:30 to 40:60, 70:30 to 50:50, 60:40 to 20:80, 60:40 to 30:70, It may be included in a volume ratio of 60:40 to 40:60, 60:40 to 50:50, 50:50 to 20:80, or 50:50 to 30:70, for example, 50:50 to 40. It may be included in a volume ratio of :60, but is not limited to this.

In the present invention, the plant may be soybean or strawberry, but is not limited thereto.

Another aspect of the present invention is spraying or immersing a plant growth promoting composition containing a microbial agent containing the Pennybacillus polymyxa MDBDO strain deposited under accession number KCTC14179BP, its culture medium, or a fraction of its culture medium, on plants or plant seeds. or a plant growth promotion method comprising a treatment step of irrigation.

In ^the present invention, ^the microbial ^agent may contain the Pennybacillus polymyxa MDBDO strain at a concentration ^of 1 ^{ml , 1 _ _ _ _ _ cfu / ml , 1 _ _ 10 8 cfu / ml , 1 _ It may be} included at ^a concentration ^of 1 It may be done, but it is not limited to this.

The culture medium may contain one or more selected from the group consisting of IAA, IBA, and D-2,3-butanediol, but is not limited thereto.

In the present invention, the composition may additionally include a chemical fertilizer containing one or more selected from the group consisting of nitrogen, phosphoric acid, potassium, magnesium, and boron, but is not limited thereto.

The composition may contain a microbial agent and a chemical fertilizer in a volume ratio of 80:20 to 20:80, preferably 80:20 to 30:70, 80:20 to 40:60, and 80:20 to 50: 50, 70:30 to 20:80, 70:30 to 30:70, 70:30 to 40:60, 70:30 to 50:50, 60:40 to 20:80, 60:40 to 30:70, It may be included in a volume ratio of 60:40 to 40:60, 60:40 to 50:50, 50:50 to 20:80, or 50:50 to 30:70, for example, 50:50 to 40. It may be included in a volume ratio of :60, but is not limited to this.

The composition may be used individually, mixed at the time of application, or used in a premixed form, but is limited thereto. It doesn't work.

The processing step may be performed 1 to 4 times a month, preferably 1 to 3 times a month, for example, 1 to 2 times, but is not limited thereto.

When performing the above treatment steps, when the microbial agent and chemical fertilizer are treated separately with a difference, the time difference between treating one type of the microbial agent and chemical fertilizer first and treating the other type is 12 to 96 hours. It may be, preferably 12 to 84 hours, 12 to 72 hours, 12 to 60 hours, 12 to 48 hours, 12 to 36 hours, 12 to 30 hours, 12 to 24 hours, 18 to 96 hours, 18 to 84 hours. Hours, 18 to 72 hours, 18 to 60 hours, 18 to 48 hours, 18 to 36 hours, 18 to 30 hours, 18 to 24 hours, 24 to 96 hours, 24 to 84 hours, 24 to 72 hours, 24 to 60 hours The time may be 24 to 48 hours, or 24 to 36 hours, for example, 24 to 30 hours, but is not limited thereto.

In the present invention, the plant may be soybean or strawberry, but is not limited thereto.

Another object of the present invention relates to the use of the culture medium of the Pennybacillus polymyxa MDBDO strain deposited under the accession number KCTC14179BP to promote plant growth.

The present invention relates to a composition for promoting plant growth containing a microbial agent containing a Paenibacillus polymyxa MDBDO strain or a culture medium thereof, and a method for producing the same. The present invention relates to a composition for promoting plant growth and a method for producing the same, and confirms the plant growth promoting function of the Paenibacillus polymyxa MDBDO strain. And, as a result of treating strawberries, which are representative facility crops, and soybeans, which are field crops, either alone or mixed with chemical fertilizers, it was confirmed that they had growth promotion and yield increase effects that were similar to or far superior to chemical fertilizers. In addition, it was confirmed that the decrease in total chlorophyll content of crop leaves caused by chemical fertilizers could also be resolved.

Therefore, the agricultural microbial fertilizer completed according to the present invention can solve environmental problems and problems such as salt accumulation in the soil as an effective substitute or reducer for chemical fertilizers. In addition, it can promote crop growth, advance crop harvest time, and contribute to farm income by increasing yield.

Figure 1 is a graph showing the results of fed-batch culture of Paenibacillus polymyxa MDBDO strain in a 5 L fermenter according to an embodiment of the present invention.
Figure 2 is a photograph confirming the growth of soybeans through a soybean small packaging experiment according to an embodiment of the present invention.
Figure 3 is a photograph confirming the growth improvement of strawberries through a strawberry small packaging experiment according to an embodiment of the present invention.
Figure 4 is a graph showing the results of fed-batch culture of the Pennybacillus polymyxa MDBDO strain in a 100 L fermenter according to an embodiment of the present invention.
Figure 5 is a photograph comparing the soybean yield in the Pennybacillus polymyxa MDBDO strain culture dilution and chemical fertilizer treatment according to an embodiment of the present invention.
Figure 6 is a photograph comparing the strawberry yield in the Pennybacillus polymyxa MDBDO strain culture dilution and chemical fertilizer treatment according to an embodiment of the present invention.
Figure 7 is a graph comparing the total chlorophyll content measured from strawberry leaves in the Pennybacillus polymyxa MDBDO strain culture dilution and chemical fertilizer treatment according to an embodiment of the present invention.

Hereinafter, the present invention will be described in more detail through the following examples. However, these examples are only for illustrating the present invention, and the scope of the present invention is not limited by these examples.

Throughout this specification, “%” used to indicate the concentration of a specific substance means (weight/volume)% for solid/solid, (weight/volume)% for solid/liquid, and Liquid/liquid is (volume/volume)%.

Example 1: Functional exploration of Pennybacillus polymyxa MDBDO strain

1-1. Determination of availability of insoluble nutrients

To measure the solubilization ability of Paenibacillus polymyxa MDBDO strain (Accession number: KCTC14179BP) to insoluble nutrients, phosphate solubilized solid medium (Pikovskaya) and zinc solubilized solid medium (Modified Bunt and Rovira medium: Glucose 10 g) , Potassium chloride 1.0 g, Potassium dihydrogen phosphate 0.1 g, Magnesium sulphate 0.2 g, 0.1% 5.0 mM Zinc phosphate, 1.5% Agar) were used.

After inoculating the strain into NB (Nutrient Broth) liquid medium, 10 ul of the culture medium containing the strain was added to the phosphate-solubilized and zinc-solubilized solid medium and cultured at 30°C for more than 7 days. By confirming the degree of formation of a clear zone around the cultured strain, the function of the strain for phosphate solubilization and zinc solubilization was confirmed.

1-2. Ammonification ability investigation

The medium used to check the ammonification ability of the strain was peptone water (1% peptone, 0.5% NaCl, pH 7), and after inoculation with the strain, it was cultured with shaking at 30°C at 180 rpm for 12 hours. After adding 0.2 ml of Nessler's reagent to 5 ml of culture medium containing the strain, the absorbance was measured at 420 nm.

1-3. IAA, IBA formation ability investigation

To confirm the ability to form IAA (indole acetic acid) and IBA (Indole 3-butyric acid), the strain was inoculated into NB medium and then pre-cultured by shaking at 30°C for more than 18 hours. Afterwards, 2% of the strain was inoculated into NB medium supplemented with 0.15% (w/v) tryptophan and cultured for 1 to 5 days to measure IAA production. 1 ml of reagent (Salkowski's Reagent) was mixed with 1 ml of supernatant obtained by centrifuging the culture medium, reacted at 30°C for 30 minutes, and absorbance was measured at 535 nm.

Phosphate solubilizing ability and zinc solubilizing ability transparent zone length: +: 1~3 mm, ++: 3~5 mm

Ammonia function: +: 0.3 uM, ++: 0.6 uM, (+++: 1 uM or more (dark brown)

Ability to form IAA and IBA: +: < 10 μg/ml, ++: < 20 μg/ml, +++: 30 μg/ml

Phosphoric acid solubilization ability Zinc solubilization ability Ammonification IAA formation IBA Formation P. polymyxa MDBDO + ++ +++ +++ +

As can be seen in Table 1, both phosphoric acid solubilizing ability and zinc solubilizing ability were confirmed, excellent zinc solubilizing ability was confirmed, and it was confirmed that a large amount of ammonia was performed as an organic nitrogen source within 12 hours of inoculation. In addition, IAA showed a production capacity of up to 22.39 μg/ml, and IBA showed a production capacity of up to 11.06 μg/ml.

From the above results, it was confirmed that the Pennybacillus polymyxa MDBDO strain has the ability to solubilize insoluble nutrients in the soil and performs excellent ammonification in a short period of time.

Example 2: Small packaging experiment using Pennybacillus polymyxa MDBDO strain

2-1. Preparation of penibacillus polymyxa MDBDO strain culture medium

Pennybacillus polymyxa MDBDO strain culture was prepared through fed-batch culture using a 5 L fermenter. The medium for fed-batch culture is the optimal production medium (60.0 g/L glucose, 30.0 g/L yeast extract, 3.0 g/L (NH ₄ ) ₂ SO ₄ , 1.2 g/L KH ₂ PO ₄ , 0.2 g/L Na ₂ HPO ₄ , 0.2 g/L MgSO ₄ ·7H ₂ O, 3 mL/L trace element solution) was used, and the trace element solution was 3 mL HCl, 0.4 g/L FeSO ₄ , 5.0 MnCl ₂ ·4H ₂ O, 0.1 g/L ZnSO ₄ ·7H ₂ O, 0.8 g/LH ₃ BO ₃ , 0.04 g/L CuSO ₄ ·5H ₂ O, 0.04 g/L NaMoO ₄ ·2H ₂ O, 0.08 g/ L Co(NO ₃ ) ₂ ·6H ₂ O, 1.0 g/L CaCl ₂ ·2H ₂ O, and 1.0 g/L biotin (Biotin) were used.

The substrate for fed-batch culture was supplied at 900 g/L glucose, and was supplied intermittently to maintain the glucose concentration in the culture medium at a level of 5 to 70 g/L. Fed-batch culture was performed for 36 hours under the following conditions: culture temperature of 37°C, inoculum amount of 10% (v/v), stirring speed of 500 rpm, air injection amount of 0.2 vvm, and pH 6.0.

As can be seen in Figure 1, D-2,3-butanediol (D-2,3-BDO) and bacterial cells were secured, and a strain culture dilution was prepared at a concentration of 1 × 10 ⁶ cfu/ml.

2-2. Evaluation of soybean growth promotion effect

After planting commercially available soybean seeds (Daewon) in the pot, ¹⁰ ml of the strain culture diluted with Pennybacillus polymyxa MDBDO strain culture to a concentration of 1 After this, a second treatment was performed in the same manner. One week after the second treatment, stem and root elongation of each treatment was examined. The control group was irrigated with the same volume of water, and all experiments were repeated three times.

Stem Length (cm) root length (cm) Control 8.5 ± 0.93 ^b 9.02 ± 0.80 ^b MDBDO treatment area 14.8 ± 1.32 ^a 12.0 ± 0.79 ^a

As can be seen in Table 2 and Figure 2, when treated with the MDBDO strain culture dilution, stem elongation and root elongation occurred significantly, with stems elongating approximately 1.7 times and roots elongating 1.3 times compared to the control.

2-3. Evaluation of strawberry growth promotion effect

After transplanting commercially available strawberry seedlings (Seolhyang) into pots ^{, 50} ml of the strain culture diluted with Pennybacillus polymyxa MDBDO strain culture to a concentration of 1 The soil was treated with irrigation, and 7 days after the last treatment, the number of strawberry leaves, leaf width, fresh weight and dry weight of strawberry stems and roots were measured. Dry weight was measured by measuring the fresh weight and drying it in an oven at 65°C.

number of leaves
(Number/Plant) width of the leaf
( ^cm2 ) fresh weight
(g) dry weight
(g) Control 18.67 ± 0.67 ^b 88.93 ± 4.79 ^b 13.07± ^0.87b 2.39± ^0.23b MDBDO treatment area 24.00 ± 1.73 ^a 125.18 ± 6.66 ^a 21.78± ^1.57a 6.13± ^1.23a

As can be seen in Table 3 and Figure 3, the strain culture dilution treatment group showed a significant difference in overall above-ground growth compared to the control group, and roots also showed more growth. Leaf width, number of leaves, fresh weight, and dry weight all also increased.

As described above, the strain and its culture medium used in the present invention showed effects such as increased stem and root elongation, increased number and width of leaves, and increased weight in soybeans and strawberries. Through these results, it was confirmed that the present invention has an excellent effect on improving the overall growth of crops, and the efficacy of the present invention was evaluated in actual cultivation.

Example 3: Growth promotion and yield increase in house cultivation using Pennybacillus polymyxa MDBDO strain

3-1. Manufacture of Pennybacillus polymyxa MDBDO strain culture media and chemical fertilizers

An attempt was made to confirm the effect of reducing chemical fertilizers using the crop growth promotion effect induced by treating the strain culture dilution in Example 2. The treatment amount of existing chemical fertilizers was reduced by half, and the effects of increasing growth and yield were evaluated when treated with microbial agents together.

Specifically, the Pennybacillus polymyxa MDBDO strain culture medium and chemical fertilizer manufacturing method are as follows.

Pennybacillus polymyxa MDBDO strain culture medium was prepared through fed-batch culture in the same manner as in Example 2-1 using a 100 L fermenter, except that the culture temperature was 37°C, the inoculum amount was 10% (v/v), and the stirring speed was 120 rpm. , was carried out for 36 hours under the conditions of 0.2 vvm of air injection and pH 6.0, and after securing the strain culture medium, it was formulated in liquid or freeze-dried form in powder form. As a result, D-2,3-butanediol and bacterial cells were obtained as shown in Figure 4.

3-2. Evaluation of the effect of promoting soybean growth and increasing yield

Commercially available soybean (Daewon) seeds were germinated for about 10 days and transplanted into a field (located in Yongbong-dong, Gwangju Metropolitan City). At two-week intervals after transplantation, strain culture dilution and chemical fertilizer (type 2 complex (8% nitrogen, 8% phosphoric acid, 9% potassium, 2% magnesium, 0.2% boron)) used to promote actual crop growth are applied to growing plants. The growth and yield of soybeans were investigated by drenching them.

Specifically, at 2-week intervals after transplantation ^, strain culture diluent (1 The mixed treatment solution was irrigated into the root zone soil a total of 3 times, 100 mL each. Twenty days after the last treatment, the size of soybean stems and leaves was measured. After 3 months, the entire plant was moved from the packaging to a well-ventilated room and dried, and then the dry weight of the beans and the weight and number of harvested seeds were measured.

stem length
(cm) width of the leaf
( ^cm2 ) dry weight
(g) seed weight
(g) number of seeds Control 48.96± ^2.61c 120.5
±7.36 ^b 155.94
±13.1 ^b 99.89
±7.34 ^c 446.00
±61.7 ^c 100% chemical fertilizer treatment unit 65.59± ^3.68b 138.03
±6.90 ^a 197.78
±23.4 ^a 112.96
±17.0 ^b.c. 411.00
±51.7 ^b.c. MDBDO treatment area 77.70± ^4.69a 153.32
± ^4.63a 210.00
±16.7 ^a 185.61
±29.3 ^ab 669.33
±101.1 ^ab 50% chemical fertilizer + MDBDO treatment 71.52± ^4.65ab 164.15
± ^6.65a 216.09
±31.8 ^a 215.89
±22.8 ^a 793.67
±82.6 ^a

As can be seen in Table 4 and Figure 5, the MDBDO treatment group and the 50% chemical fertilizer + MDBDO treatment group showed higher values than the control group as well as the 100% chemical fertilizer treatment group in all evaluation items, including leaf width, dry weight, seed weight, and seed The number of 50% chemical fertilizer + MDBDO treatment group was the highest.

3-3. Evaluation of strawberry growth promotion and yield increase effects

Young strawberry seedlings (Seolhyang) were transplanted into a greenhouse medium cultivation facility (located in Unnam-dong, Gwangju). Strain culture diluent freeze-dried for 2 months starting 3 weeks after transplantation and chemical fertilizer used to promote actual crop growth (Rojasol S 311 (nitrogen 30%, phosphoric acid 10%, potassium 10%, kaolin 2%, boron 0.01%) ), strain culture dilution and chemical fertilizer mixture were applied to the growing strawberry rhizosphere medium to investigate the growth and yield of strawberries.

1st month 2nd month Control - - - - 100% chemical fertilizer treatment unit Chemical fertilizer 50 ml chemical fertilizer
50ml chemical fertilizer
50ml chemical fertilizer
50ml MDBDO treatment area - 100 ml of culture diluent - culture diluent
100ml 50% chemical fertilizer + MDBDO treatment chemical fertilizer
50ml culture diluent
50ml chemical fertilizer
50ml culture diluent
50ml

Specifically, For the strain culture dilution treatment group (MDBDO), a culture dilution with a concentration of ¹

The chemical fertilizer treatment group (100% chemical fertilizer) was treated with 50 mL of chemical fertilizer diluted to a concentration of 1 g/L twice a month at daily intervals, that is, a total of 4 times for 2 months.

In the mixed treatment group (50% chemical fertilizer + MDBDO), 50 ml of the above chemical fertilizer and 50 ml of culture diluent were applied once a day, and then once a month in the same manner based on the date of chemical fertilizer treatment, that is, for a total of two months. Irrigation was performed 4 times.

Two weeks after the last treatment, the stem length and leaf width of strawberries were measured, and leaf sampling was conducted to investigate chlorophyll content. Maturity was judged based on the color of the fruit, and mature strawberry fruits were harvested at weekly intervals and their weight and number were measured. Afterwards, items regarding growth characteristics and yield increase were evaluated.

To measure chlorophyll content, chlorophyll was extracted from strawberry leaves using an 80% acetone extraction method. Absorbance was measured at wavelengths of 663 nm and 645 nm using a spectrophotometer, and the total chlorophyll content was calculated by substituting it into the formula.

stem length
(cm) width of the leaf
( ^cm2 ) fruit weight
(g) number of fruits chlorophyll
content (%) Control 5.60± ^0.15b 34.44
±1.04 ^b 319.37
±92.88 ^b 15.67
±2.96 ^b 48.23
± ^2.06b 100% chemical fertilizer treatment unit 8.68± ^0.43a 49.12
±2.58 ^a 601.06
±40.60 ^a 33.67
±2.60 ^a 41.04
±4.14 ^b MDBDO treatment area 6.50± ^0.20a 39.58
± ^1.04a 545.82
±89.57 ^ab 34.00
± ^4.04a 60.68
± ^0.98a 50% chemical fertilizer + MDBDO treatment 6.53± ^0.25a 41.39
± ^1.22a 646.97
±46.04 ^a 41.67
± ^1.76a 59.24
±3.18 ^a

As can be seen in Table 6 and Figures 6 and 7, in the mixed treatment group, fruit weight and number of fruits increased compared to the control and chemical fertilizer treatments, and both stem length and leaf width also increased compared to the control group. Chlorophyll content also significantly increased in both strain-only and mixed treatments.

Claims (14)

Culture dilution ^of Paenibacillus polymyxa MDBDO strain deposited with accession number KCTC14179BP at a concentration of ¹ and
Chemical fertilizer at a concentration of 1 to 1.25 g/L containing at least one selected from the group consisting of nitrogen, phosphorus, potassium, magnesium, and boron;
A composition for promoting plant growth comprising a volume ratio of 70:30 to 50:50. delete The method of claim 1, wherein the culture diluent is one selected from the group consisting of IAA (indole acetic acid), IBA (Indole 3-butyric acid), and D-2,3-butanediol (D-2,3-BDO). A composition for promoting plant growth containing the above. delete delete The composition for promoting plant growth according to claim 1, wherein the plant is soybean or strawberry. A culture step ^of culturing the Paenibacillus polymyxa MDBDO strain deposited with accession number KCTC14179BP to prepare a culture dilution with a concentration of the strain of ¹ and
The culture dilution solution; and a chemical fertilizer at a concentration of 1 to 1.25 g/L containing at least one selected from the group consisting of nitrogen, phosphorus, potassium, magnesium, and boron. A mixing step of mixing at a volume ratio of 70:30 to 50:50;
A method for producing a composition for promoting plant growth comprising. The method of claim 7, wherein the culturing step is performed for 24 to 48 hours at a temperature of 25 to 45°C and a pH of 4.5 to 7.5. delete delete Culture dilution ^of Paenibacillus polymyxa MDBDO strain deposited with accession number KCTC14179BP at a concentration of ¹ and
Chemical fertilizer at a concentration of 1 to 1.25 g/L containing at least one selected from the group consisting of nitrogen, phosphorus, potassium, magnesium, and boron;
A method of promoting plant growth comprising the step of spraying, immersing or irrigating plants or plant seeds with a composition for promoting plant growth comprising a volume ratio of 70:30 to 50:50. delete delete delete