JP6878751B2 - Soil infectious disease mitigation material - Google Patents

Description

The present invention relates to a soil infectious disease reducing material.

Various proposals have been made for the purpose of controlling soil-borne diseases.

For example, in Patent Document 1, a new filamentous strain that can infect and coexist with the roots of various plants and has an ability to control soil-borne diseases, and a soil-borne disease control material containing cells or cultures of the strain. , A soil-borne disease control method for plants using this has been proposed.

In Patent Document 2, it has a high control effect against soil-borne diseases caused by phytopathogenic filamentous fungi containing photosynthetic bacteria and Bacillus bacteria as active ingredients, has a low environmental load, is safe and has chemical damage. There have been proposed microbial pesticides that do not exist and methods that can effectively control soil-borne diseases by using the microbial pesticides.

Patent Document 3 proposes a soil infectious disease control method that promotes crop growth.

Japanese Unexamined Patent Publication No. 2008-67667 Japanese Unexamined Patent Publication No. 2015-39359 Japanese Unexamined Patent Publication No. 2015-61826

An object of the present invention is to propose a novel soil-borne disease reducing material.

[1]
A soil-borne disease-reducing material containing three types of Bacillus bacteria with different characteristics in a carrier material.

[2]
The carrier material is a soil-borne disease reducing material according to [1], which is a porous carrier material having a pore size of μm or more.

[3]
The soil infectious disease reducing material of [1] or [2] which has been dried to a water content of 5 to 10%.

[4]
A soil-borne disease reducing material according to any one of [1] to [3], which has a bacterial concentration of 1.0 × 10 ⁴ cfu / g to 9.0 × 10 ^{7 cfu / g.}

[5]
A soil-borne disease-reducing material that contains three types of Bacillus bacteria with different characteristics in a pre-molded carrier material.

[6]
The carrier material that has been molded in advance is the soil-borne disease reducing material according to [5], which is molded into granules having a particle size of 2 mm to 10 mm.

[7]
The carrier material is a soil-borne disease reducing material according to [5] or [6], which is a porous carrier material having a pore size of μm or more.

[8]
The soil infectious disease reducing material according to any one of [5] to [7], which has been dried to a water content of 5 to 10%.

[9]
A soil-borne disease reducing material according to any one of [5] to [8], which has a bacterial concentration of 1.0 × 10 ⁴ cfu / g to 9.0 × 10 ^{7 cfu / g.}

[10]
A soil-borne disease-reducing material formed by molding a carrier material containing three types of Bacillus bacteria with different characteristics.

[11]
[10] Soil-borne disease reducing material molded into granules having a particle size of 2 mm to 10 mm.

[12]
The carrier material is a soil-borne disease reducing material according to [10] or [11], which is a porous carrier material having a pore size of μm or more.

[13]
The soil infectious disease reducing material according to any one of [10] to [12], which has been dried to a water content of 5 to 10%.

[14]
A soil-borne disease reducing material according to any one of [10] to [13], which has a bacterial concentration of 1.0 × 10 ⁴ cfu / g to 9.0 × 10 ^{7 cfu / g.}

[15]
The carrier material comprises any one or a combination of one or more of dried chicken manure, fermented chicken manure, fermented cow manure, fermented pork manure, diatomaceous earth, zeolite, lightweight aerated concrete, and green pseudo-ashite [1] to [14]. Any soil-borne disease mitigation material.

[16]
The carrier material comprises one or more of fermented beef manure, fermented pork manure, diatomaceous earth, zeolite, lightweight bubble concrete, green pseudo-ashite, and a combination of dried chicken manure and / or fermented chicken manure, or dried. A soil-borne disease reducing material according to any one of [1] to [14], which comprises chicken manure and / or fermented chicken manure.

[17]
The three types of Bacillus bacteria with different characteristics are Bacillus amyloliquefaciens (accession number: NITE P-02337), Bacillus subtilis (accession number: NITE P-02338), and Bacillus subtilis (accession number: NITE P-02354) [1]. ] To [16], a soil-borne disease reducing material.

According to the present invention, it is possible to provide a novel soil-borne disease reducing material.

The figure which shows the molecular phylogenetic tree by the 16S-rRNA gene about the bacterium of the genus Bacillus used in this invention. A reference photograph showing the results of confrontational culture of Bacillus amyloliquefaciens (APU-W01), Bacillus subtilis (APU-O02), and Bacillus subtilis (APU-T03) with Calonectria licicola, the causative agent of black root rot. A reference photograph showing the results of examining the response of Bacillus amyloliquefaciens (APU-W01) strain and Bacillus subtilis (APU-O02) strain to chitin. A reference photograph showing the results of examining the effect of the inhibitory bacterial solution on black root rot by the Pot test. A reference photograph showing the results of examining the effect of the application of soil-borne disease mitigation materials on soybean black root rot infection. The figure which shows the result of having examined the presence or absence of the black root rot infection in the underground part of soybean by applying the soil infectious disease reducing material. The figure which shows the result of having examined the incidence of black root rot of soybean by the application of the soil infectious disease reducing material in each growing season. The figure which shows the result of having examined the incidence of black root rot of green soybean by applying a soil infectious disease reducing material. The figure which shows the result of having examined the influence which the presence or absence of the application of the soil infectious disease reducing material has on the transition of the dry matter weight of soybean.

Conventionally, Bacillus bacteria have been known to be useful bacteria having characteristics such as plant growth promotion, disease control, and odor reduction.

The inventors of the present application selected three species of Bacillus bacteria having different characteristics from the Bacillus bacteria, and examined the response to soil-borne diseases when applied to plants.

Through this study, it was found that the simultaneous use of three types of Bacillus bacteria having different characteristics exerts an effect of reducing soil-borne diseases.

In addition, by incorporating three types of Bacillus bacteria with different characteristics into the carrier material to make a soil-borne disease reducing material, the effect of reducing soil-borne diseases can be stabilized, and soil-borne diseases can be reduced. It was found that the number of bacteria in the wood and its activity can be stabilized.

Further, three types of Bacillus bacteria having different characteristics are impregnated in a carrier material and molded to obtain a soil infectious disease reducing material, or three types of Bacillus spp. By including bacteria to make a soil-borne disease reducing material, the effect of reducing soil-borne diseases can be stabilized, and the number of bacteria and their activity in the soil-borne disease reducing material can be stabilized. I found that I could do it.

As the carrier material containing the three types of Bacillus bacteria having different characteristics, a porous carrier material having a minute pore size can be used. It is desirable that it is porous with a minute pore size in order to support three types of Bacillus bacteria having different characteristics. As the minute pore diameter, a porous carrier material having a pore diameter of μm unit, a porous carrier material having a pore diameter of μm unit or more, and the like can be adopted.

In the above, the soil infectious disease reducing material can be dried to a water content of 5 to 10%. This water content is desirable from the viewpoint of suppressing the growth of other bacteria and stabilizing the number of bacteria and their activity in the soil infectious disease reducing material.

The carrier material may consist of any one or a combination of dried chicken manure, fermented chicken manure, fermented cow manure, fermented pork manure, diatomaceous earth, zeolite, lightweight aerated concrete, and green pseudo-ashite.

Alternatively, from a combination of one or more of fermented beef manure, fermented pork manure, diatomaceous earth, zeolite, lightweight bubble concrete, green pseudo-ashiwa and dried chicken manure and / or fermented chicken manure, or dried chicken manure and / or. The carrier material can also be composed of fermented chicken manure.

As the carrier material, as described above, a porous carrier material having a minute pore size, for example, a porous carrier material having a pore size of μm unit, a porous carrier material having a pore size of μm unit or more, and the like can be used. When adopted, any one or more of diatomaceous earth, zeolite, lightweight aerated concrete, and green pseudoashite, which are porous bodies having such a minute pore size, are used as the material constituting the carrier material. It can be included in one of them.

Further, as will be described later, when Bacillus bacteria isolated from dried chicken manure are used as the three types of Bacillus bacteria having different characteristics, the growth rate of the three types of Bacillus bacteria in the soil-borne disease reducing material. From the viewpoint of high resistance to production stress, the carrier material can be composed of dried chicken manure and / or fermented chicken manure, or can be a carrier material containing at least dried chicken manure and / or fermented chicken manure.

A product molded using the above-mentioned carrier material can be used as a molded carrier material (= molding material). For example, a carrier material (= molding material) that is molded into particles having a particle size of 2 mm to 10 mm can be used.

In addition to using the carrier material (= molding material) molded as described above, the carrier material described above contains three types of Bacillus bacteria having different characteristics, and this is molded to form a soil-borne disease reducing material. You can also do it. For example, it can be molded into granules having a particle size of 2 mm to 10 mm.

In this case as well, it can be dried to a water content of 5 to 10% to obtain a soil-borne disease reducing material. For example, it is dried to a water content of 5 to 10% and then molded, or after the molding treatment, it is dried to a water content of 5 to 10%.

By including three types of Bacillus bacteria having different characteristics in the above-mentioned carrier material, or by molding the above-mentioned carrier material, that is, the molded carrier material (= molding material) has characteristics. By incorporating three different types of Bacillus bacteria, or by impregnating the above-mentioned carrier material with three types of Bacillus bacteria having different characteristics and molding it, the soil-borne disease reducing material of the present invention can be obtained. can do.

In the above, it is desirable that the bacterial concentration in the soil infectious disease reducing material is 1.0 × 10 ⁴ cfu / g to 9.0 × 10 ^{7 cfu / g.}

As described above, by incorporating three types of Bacillus bacteria having different characteristics into the carrier material, the effect of reducing soil-borne diseases can be stabilized. In addition, it is possible to stabilize the number of bacteria and their activity in the soil infectious disease reducing material.

In order to include three types of Bacillus bacteria having different characteristics in the carrier material, for example, three types of Bacillus bacteria having different characteristics can be cultured and included in the carrier material.

For example, three types of Bacillus bacteria having different characteristics are cultivated to prepare a mixed solution in which these three types are mixed, and this is added to the carrier material in the range of 2 to 40% by mass ratio, and then the water content is 5 to 10. It can be dried to% to be a soil-borne disease-reducing material.

From the viewpoint of exerting the effect of reducing soil-borne diseases, the soil-borne disease reducing material has a bacterial concentration of 1.0 × 10 ⁴ cfu / g to 9.0 × 10 ^{7 of three types of Bacillus bacteria having different characteristics.} It is desirable to be cfu / g.

Therefore, when three types of Bacillus bacteria having different characteristics are cultivated to prepare a mixed solution in which these three types are mixed, and this is added to the carrier material in the range of 2 to 40% by mass ratio, the soil of the final product is used. cell concentration of bacteria belonging to the genus Bacillus three having different characteristics in infectious disease relief material performed while adjusted to ^{1.0 × 10 4 cfu / g~9.0 ×} 10 7 cfu / g.

In addition, when three types of Bacillus bacteria having different characteristics are mixed to form a mixed solution, the concentration of the three types of Bacillus bacteria having different characteristics in the final product soil-borne disease reducing material is 1. Mixing is performed while considering the ratio of 0.0 × 10 ^{4 cfu / g to 9.0 × 10 7 cfu / g.} For example, the three types of Bacillus bacteria having different cultured characteristics can be mixed in a predetermined mass ratio. As the mixing at a predetermined mass ratio, for example, the three types of Bacillus bacteria having different cultured characteristics can be mixed at an equal mass ratio.

As one of the soil-borne diseases, soybean black root rot, which is a soil-borne wilt disease caused by Calonectria ilicicola, is known. Soybean black root rot has become a serious problem because control technology has not been established.

In Odate City, Akita Prefecture, there is a field where soybeans have been continuously cultivated for 27 years, yet high yields have been maintained, and diseases such as soybean black root rot have hardly occurred. Certain dried cow dung was applied annually in this field.

Therefore, the inventors of the present application speculate that there may be a microorganism that suppresses soybean black root rot in the dried chicken manure, and attempt to separate the microorganism that suppresses soybean black root rot from the dried chicken manure. By examining the use of the isolate, the soil infectious disease can be reduced by simultaneously using three types of Bacillus bacteria having different characteristics, and this can be used as a soil infectious disease reducing material. Is completed.

In this way, the three Bacillus spp. Bacteria with different characteristics isolated and selected by the inventors of the present application are the Bacillus amyloliquefaciens1 strain and the Bacillus subtilis2 strain. All of them have been deposited at the Patent Microorganisms Depositary Center of the National Institute of Technology and Evaluation, and have received the following deposit numbers. Bacillus amyloliquefaciens (accession number: NITE P-02337), Bacillus subtilis (accession number: NITE P-02338), Bacillus subtilis (accession number: NITE P-02354).

In addition, related patent applications have already been filed for these three species of Bacillus bacteria (Patent Application Number: Japanese Patent Application No. 2016-191581).

(Classification of strains)
As described above, three strains of Bacillus bacteria having different characteristics selected from Bacillus bacteria were identified by decoding the nucleotide sequences of the 16S-rRNA genes, and the results shown in FIG. 1 were obtained.

As a result of this 16sRNA analysis, as shown in Table 1, the above three strains (Bacillus amyloliquefaciens (accession number: NITE P-02337), Bacillus subtilis (accession number: NITE P-02338), which are effective against soil-borne diseases. ), Bacillus subtilis (accession number: NITE P-02354)), Bacillus amyloliquefaciens (APU-W01, hereinafter referred to as W-01 in the present specification and drawings), Bacillus subtilis (APU-O02, hereinafter referred to as this), respectively. It was shown to be O-02 in the specification and drawings) and Bacillus subtilis (APU-T03, hereinafter referred to as T-03 in the present specification and drawings).

(Adjustment of test strain and inoculum)
W-01, O-02, and T-03 were used as the test strains. To prepare the bacterial solution, dissolve the LB medium in distilled water, inoculate each single strain into an autoclave-sterilized liquid medium, and incubate in an incubator at 35 ° C. for 3 days while stirring with a stirrer. I went there. The inoculant was adjusted by mixing three types of bacterial solutions cultured alone in the same weight ratio.

(Effect of medium pH)
After dissolving LB medium and agar in distilled water, the pH was adjusted to 5.0 to 9.0 with hydrochloric acid and sodium hydroxide, and autoclave sterilization was performed to prepare a plate. The strains were applied to the prepared plates, respectively, and cultured at 35 ° C. for 12 hours. The number of colonies after culturing was counted, and the proliferative property (measured value / theoretical value) was evaluated. Regarding proliferative property, those without colonization were shown as −, those with <0.5 were shown as +, those with 0.5 ≦ x <1 were shown as ++, and those with 1 = were shown as +++.

The evaluation results (proliferation of the three strains at different pH values) are shown in Table 2.

(result)
As a result of evaluating the influence of the medium pH (Table 2), it was shown that the proliferative property of each of the three strains was different for each pH. In particular, W-01 was highly proliferative at pH 7.0-9.0 on the alkaline side, and T-03 was highly proliferative at specific pHs of pH 6.0 and 7.0. In addition, O-02 had a feature of a wide suitability range with a pH of 6.0 to 9.0. On the other hand, all the bacteria showed low proliferative potential when the pH was 6.0 or less. From the above results, it was suggested that the growth potential was high in the range of 6.0 to 6.5, which is the optimum pH for soybean growth, and it was clarified that the responses of the three strains to the medium pH were different.

(Proliferative under low temperature conditions)
After dissolving the LB medium and agar in distilled water (pH 7.8) and sterilizing in an autoclave, a plate was prepared. The strains were applied to the prepared plates, respectively, and cultured in a dark place at 25 ° C., 15 ° C., and 10 ° C., and the number of days when colonies were detected was evaluated. Regarding the proliferative condition under low temperature conditions, those without colonization were negative, those that formed colonies within 2 days of culture were +++, those that formed colonies within 5 days were ++, and those that formed colonies within 6 days were formed. Things are shown as +.

The evaluation results (proliferation of the three strains at low temperature) are shown in Table 3.

(result)
As a result of examining the proliferative property under low temperature conditions (Table 3), colonies were detected in all the strains after culturing within 6 days under the condition of 15 ° C. In particular, O-02 and T-03 were detected within 5 days, indicating that they may be highly sensitive to low temperatures. In addition, under the condition of 25 ° C., all the strains were detected within 2 days, indicating that the strain was highly proliferative. It was shown that even when a soil-borne disease-reducing material using three types of strains was plowed into the soil at low temperatures, the three types of strains could grow in the soil.

(Confrontation culture method)
Each strain was inoculated with soybean black root rot on a PDA medium, and confronted and cultured at 25 ° C. for 5 days using an incubator, and the growth inhibitory effect of each isolated strain on soybean black root rot was examined. The examination results are as shown in the reference photograph in FIG. The petri dish in the photo was inoculated with black root rot bacteria on the left side and suppressor or non-suppressor bacteria on the right side.

(result)
As a result of confronting the three strains and soybean black root rot fungus, it was shown that all the strains have a growth inhibitory effect on the black root rot fungus. The degree was estimated to be O-02>W-01> T-03. From the above results, it was shown that the three strains have a growth inhibitory effect on the black root rot fungus, and since there are strengths and weaknesses to that extent, it is possible that the growth of the black root rot fungus is suppressed by different mechanisms.

(Elucidation of mechanism: Response to chitin)
After dissolving the LB medium and agar in distilled water (pH 7.8) and sterilizing in an autoclave, a plate was prepared. Chitin powder was added to the prepared plate, and each strain was applied. Chitinase activity was estimated by observing whether each strain decomposed chitin added to the medium. The degree to which the inoculated strain made the white chitin transparent was evaluated. The examination results are as shown in the reference photograph in FIG.

(result)
As a result of estimating the chitinase activity of the strains (Fig. 3), it was shown that all the strains decomposed chitin in the medium. In particular, the activity of the W-01 strain was extremely high, and it was shown that O-02 has the activity but may maintain the activity slowly (Date not shown). From the above results, it was shown that the fact that each strain has chitinase activity may be one of the factors that suppress the growth of black root rot bacteria.

(Pot test)
Soybean (Glycine max (L.) Merr) was used as the test plant, and Ryuhou was used as the variety. As the soil, sandy loam soil of Aomori prefecture was used, and black root rot fungus was added at a concentration of 10 to the 8th power to set an infected area.

Seeds sterilized with 70% ethanol and hypochlorous acid in a treatment group with or without inoculation of a suppressive bacterial solution in which three types of bacteria were mixed in the prepared medium (inoculation concentration: 10 8-row cfu / ml). Was sown. After sowing, distilled water was appropriately added in a plant incubator, and the cells were cultured under the conditions of light period / dark period: 28 ° C./18 ° C. (16h / 8h). After culturing, the effect of black root rot was evaluated by observation. The examination results are as shown in the reference photograph in FIG.

(result)
In the Pot test, the effect of inoculation of 3 strains on black root rot was evaluated (Fig. 4), and it was shown that the group to which the inhibitory bacteria mixed with 3 strains were added did not affect the germination and initial growth of soybean. .. In the group to which the inhibitory bacterial solution was not added, the infection concentration of black root rot fungus was high, but it was shown that it significantly affected germination and initial growth.

(Examination of materialization)
As carrier materials, fermented chicken manure, lightweight aerated concrete (ALC), and charcoal chicken manure were examined. After culturing 3 types of Bacillus amyloliquefaciens (APU-W01), Bacillus subtilis (APU-O02), Bacillus subtilis (APU-T03), fermented chicken manure alone, fermented chicken manure and ALC, fermented chicken manure and charcoal-based chicken manure are mixed in a weight ratio of 40. % Was added, and after molding, heat treatment was performed for 10 hours under the condition of about 60 ° C. (7 kg / batch).

When the number of bacteria in the obtained molding material was counted and the influence of the combination of the carrier materials was evaluated, it was as shown in Table 4 (examination 1 regarding the combination of the carrier materials) and Table 5 (examination 2 regarding the combination of the carrier materials). ..

(result)
As a result of the examination (Tables 4 and 5), the influence of the combination of materials was hardly observed, but the number of bacteria tended to increase by combining other materials rather than molding the fermented chicken manure alone. .. This result is considered to be because the dispersibility of the bacterial solution was improved by adding ALC or green pseudo-ashite from the values of the physical property evaluation of the obtained molding material (date not shown).

(Consideration of long-term storage)
After culturing three types of Bacillus amyloliquefaciens (APU-W01), Bacillus subtilis (APU-O02), and Bacillus subtilis (APU-T03), 40% by weight was added to fermented chicken manure alone, and molding and heat treatment were performed. The obtained molding material was cultured in a constant temperature incubator, and the number of bacteria on the 60th day was evaluated. The results were as shown in Table 6 (results of long-term storage test).

(result)
As a result of the examination (Table 6), a 60-day culture test showed a decrease in the number of bacteria by about 35%, but it exceeded 10 to the 4th power, which shows a reduction effect, and no effect on quality was observed. Became clear.

(Examination of manufacturing stress by large-scale manufacturing machine)
After culturing three types of Bacillus amyloliquefaciens (APU-W01), Bacillus subtilis (APU-O02), and Bacillus subtilis (APU-T03), 2-10% by mass ratio was added to fermented chicken manure alone, and molded by a large-scale manufacturing equipment. After that, heat treatment was performed for 30 minutes under the condition of hot air temperature of about 100 ° C. (800 kg / batch). The number of bacteria in the obtained molding material was evaluated, and the effect of manufacturing stress on the large-scale manufacturing machine was evaluated. Table 7 (effect of manufacturing stress on the large-scale manufacturing machine) was shown.

(result)
As a result of the examination (Table 7), the initial number of bacteria decreased by about 10 times in consideration of the amount of bacterial solution added (about 10% of the mass ratio) in the granulation machine, which is subject to extremely large stress such as heat and pressure, and the heat treatment. However, it was shown that each treatment group can maintain a bacterial count of 10 to the 4th power or higher.

From the above results, it is considered that the stress resistance of the strains used as carriers for dried chicken manure and fermented chicken manure is extremely high.

A soil-borne disease reducing material was applied to the field where the plants were cultivated, and the effect was confirmed.

Soybean (Glycine max (L.) Merr) was used as the test plant, and Ryuhou was used as the variety. The test field was a paddy field conversion field in Aomori Prefecture, and this year it was conducted in the field for the second soybean crop. The soil type was sandy loam, and the soil chemistry (chemical properties of the test field) was as shown in Table 8.

For the treatment area, chemical fertilizer was applied as a conventional area (NP ₂ O ₅ -K ₂ O (%): 14-18-14), 200 kg of fermented chicken manure was applied as a carrier area, and soil infectious disease mitigation material was applied as a material area. 200 kg was applied.

The three suppressor strains (W-01, O-02, T-03) were mass-cultured in LB liquid medium and then mixed. 40% of the mass ratio of fermented chicken manure was added to the obtained mixed solution, and the molded product was used as a soil infectious disease reducing material. The microbial molding material was molded into a granular shape and a size of 2-4 mm. The bacterial concentration of the three suppressor strains was 10 5 to 6 cfu / g. Hereinafter, in this embodiment, since it is a molded soil infectious disease reducing material, it is referred to as a “microorganism molding material”.

As for the outline of cultivation, fermented chicken manure was applied to the carrier plot on April 25, microbial molding materials were applied to the material plot, and chemical fertilizer was applied to the conventional plot on June 6.

The seeding was carried out on June 7, with a furrow of 72 cm, a plant spacing of 14 cm, and two seeds.

The survey items included a symptom survey of soil-borne diseases in the underground part of soybean and a survey of the infection rate, growth and yield of soybean black root rot.

For soil infectious disease symptom investigation, plants collected during the three-leaf stage (July 8), flowering stage (July 29), and maximum flourishing season (hereinafter referred to as the most prosperous season) (September 2). The symptom of soil-borne diseases (soybean black root rot, soybean stalk epidemic, etc.) in the underground part of the plant was investigated, and the degree of disease was calculated.

For the infection rate, DNA was extracted from soybean root and PCR was performed with a primer specific to soybean black root rot fungus targeting the β-tubulin gene of filamentous fungus. Then, infection with soybean black root rot was evaluated by confirming the presence or absence of a band by agarose gel electrophoresis.

Regarding the growth and yield, the plants were collected at the three-leaf stage, the flowering stage, and the most prosperous stage, and the dry matter weight was measured.

Soybeans were mowed on October 14, and the yield and yield components were investigated.

(result)
As a result of evaluating the incidence of soil-borne diseases in the underground part of soybeans, the incidence of the material plots remained lower than that of the other two test plots from the three-leaf stage to the most prosperous stage, and the damage caused by the diseases was suppressed. Was shown (FIGS. 5 and 7).

As a result of examining the infection of soybean black root rot fungus, it was shown that the soybean black root rot fungus was not infected in the three-leaf stage (Fig. 6), and the infection was found in other stages during the flowering stage and the most prosperous stage. It was shown that the infection rate was lower than that in the two test plots (Table 9 “Infection rate of soybean black root rot fungus in different growing seasons”).

From the above, it was clarified that the microbial molding material (soil infectious disease reducing material) has the effect of reducing soybean black root rot. In addition, in the three-leaf stage, infection with soybean black root rot fungus was not observed in any of the test plots, but the disease was significantly suppressed in the material plots as compared with the conventional plots and the carrier plots (Fig. 7). Therefore, it was presumed that the microbial molding material has a suppressive effect on soil-borne diseases other than soybean black root rot.

As reference data, the test results of green soybeans are shown. As a result of applying the microbial molding material to the evening drink tea beans and the microbial molding material (200 kg / 10a), it was shown that the disease incidence was lower than that in the conventional section where the material was not applied (Fig. 8).

As a result of investigating the growth, there was no difference in the dry matter weight between the test sections until the flowering period, but it was suggested that the dry matter weight was significantly increased in the material plot than in the conventional plot at the peak season (Fig. 9). .. As a result of investigating the yield, it was shown that the microbial molding material group increased the weight of 100 grains and the yield increased in the microbial molding material group (Table 10 “Soil infectious disease mitigation material application or non-application of soybean). As a result of examining the effect on yield ").

From the above results, the microbial molding material (soil-borne disease reducing material) has an inhibitory effect on soybean black root rot fungi, and by reducing the onset of the disease, it is possible to increase or stabilize the growth and yield of soybean. It was shown that it can be done. It was also presumed to have a mitigating effect on other soil-borne diseases.

Although the embodiments and examples of the present invention have been described above, the present invention is not limited to these and can be variously modified within the technical scope grasped from the description of the scope of claims.

According to the present invention, it is possible to make a new proposal for the use of a microorganism having a mitigating effect on soil-borne diseases as a molding material. In particular, it is possible to propose a technique for stabilizing the effect of using a microorganism as a molding material, which has an effect of reducing soil-borne diseases.

After culturing three types of Bacillus bacteria having different characteristics, they are mixed at a predetermined mass ratio, for example, an equal mass ratio, and the mass ratio is 2 to a carrier material (for example, a carrier material mainly composed of dried chicken manure and fermented chicken manure). After encapsulation at a ratio of ~ 40%, it can be dried until the water content becomes 5 to 10% to obtain a soil-borne disease reducing material.

The soil infectious disease reducing material proposed by the present invention can maintain the number of bacteria and its activity for 6 months or more even under storage conditions of 25 ° C or higher, and is used in actual agricultural sites in soil. It is possible to provide a technique for stabilizing the effect of reducing infectious diseases. For example, it is possible to stabilize the effect of reducing the disease on black root rot of soybean.

It has been reported that the causative agent of soybean black root rot is soil-borne and its persistence is high. Although countermeasures have been taken, it is not always possible to treat chemical pesticides, or even if they are treated, there is little effect. Therefore, it is important to stabilize the effect of the strain used continuously as in the present invention, and this technique can be provided.

Claims (16)

Bacillus amyloliquefaciens (accession number: NITE P-02337), Bacillus subtilis (accession number: NITE P-02338), Bacillus subtilis (accession number: NITE P-02354), which are three types of Bacillus bacteria with different characteristics in the carrier material. A soil-borne disease-reducing material that has a growth-suppressing effect on Bacillus subtilis soybeans. The soil-borne disease reducing material according to claim 1, wherein the carrier material is a porous carrier material having a pore size of μm or more. The soil infectious disease reducing material according to claim 1 or 2, which has been dried to a water content of 5 to 10%. The soil infectious disease reducing material according to any one of claims 1 to 3, wherein the bacterial concentration is 1.0 × 10 ⁴ cfu / g to 9.0 × 10 ^{7 cfu / g.} Bacillus amyloliquefaciens (accession number: NITE P-02337), Bacillus subtilis (accession number: NITE P-02338), Bacillus subtilis (accession number: NITE P-02338), which are three types of Bacillus bacteria with different characteristics in pre-molded carrier materials. NITE P-02354) is a soil-borne disease-reducing material that has a growth-suppressing effect on Bacillus subtilis. The soil-borne disease reducing material according to claim 5, wherein the carrier material that has been molded in advance is formed into granules having a particle size of 2 mm to 10 mm. The soil-borne disease reducing material according to claim 5 or 6, wherein the carrier material is a porous carrier material having a pore size of μm or more. The soil infectious disease reducing material according to any one of claims 5 to 7, which has been dried to a water content of 5 to 10%. The soil infectious disease reducing material according to any one of claims 5 to 8, wherein the bacterial concentration is 1.0 × 10 ⁴ cfu / g to 9.0 × 10 ^{7 cfu / g.} Bacillus amyloliquefaciens (accession number: NITE P-02337), Bacillus subtilis (accession number: NITE P-02338), Bacillus subtilis (accession number: NITE P-02354), which are three types of Bacillus bacteria with different characteristics in the carrier material. A soil-borne disease-reducing material that has a growth-suppressing effect on soybean black root rot fungi formed by molding a material containing. The soil infectious disease reducing material according to claim 10, which is molded into granules having a particle size of 2 mm to 10 mm. The soil-borne disease reducing material according to claim 10 or 11, wherein the carrier material is a porous carrier material having a pore size of μm or more. The soil infectious disease reducing material according to any one of claims 10 to 12, which has been dried to a water content of 5 to 10%. The soil infectious disease reducing material according to any one of claims 10 to 13, wherein the bacterial concentration is 1.0 × 10 ⁴ cfu / g to 9.0 × 10 ^{7 cfu / g.} The carrier material is any one of claims 1 to 14, which comprises any one or a combination of dried chicken manure, fermented chicken manure, fermented cow manure, fermented pork manure, diatomaceous earth, zeolite, lightweight bubble concrete, and green pseudo-ashite. The soil-borne disease reducing material described in item 1. The carrier material comprises one or more of fermented beef manure, fermented pork manure, diatomaceous earth, zeolite, lightweight bubble concrete, green pseudo-ashite, and a combination of dried chicken manure and / or fermented chicken manure, or dried. The soil-borne disease reducing material according to any one of claims 1 to 14, which comprises chicken manure and / or fermented chicken manure.

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