JPH09194316A - Agent for controlling soil blight of plant of family solanaceae and controlling method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a soil blight controlling agent produced by using a specific bacterial strain separated from the root of tobacco, stably fixable to the root of a solanaceous plant such as tobacco down to the latter stage of cultivation and exhibiting high controlling effect in a greenhouse as well as on a field. SOLUTION: A microorganism belonging to Sphingomonas paucimobilis and/or its cultured product is used as an active component of the objective agent. The microorganism belonging to Sphingomonas paucimobilis is especially preferably Sphingomonas paucimobilis A260 strain. The soil blight to be controlled is bacterial wilt of tobacco, bacterial wilt of solanaceous plants, etc., caused by Pseudomonas solanacearum. The soil blight controlling agent is introduced to the root of the solanaceous plant, its cultivation field and/or its soil to control the soil blight. The solanaceous plant effective for the treatment with the agent is eggplant, tomato, green pepper, potato, etc., as well as tobacco and the agent is applicable to a host plant of the pathogen of bacterial wilt.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a soil disease control agent (especially Pseudomonas solanacearum) for a solanaceous plant containing a microorganism belonging to the scientific name Sphingomonas pasimobilis (former name: Pseudomonas pasimobilis) as an active ingredient. And a method for controlling soil diseases of solanaceous plants using the microorganism).

[0002]

2. Description of the Related Art Tobacco wilt caused by parasitism of Pseudomonas solanacearum, which is one of plant pathogenic bacteria, or bacterial wilt of Solanaceae (hereinafter abbreviated as "this disease") is produced in tobacco, tomato, Eggplant, pee
Many crops such as mans are damaged.

This pathogenic bacterium (hereinafter abbreviated to bacterial wilt) is easy to survive in the soil for a long period of time, and once it infects a plant, it grows quickly, so that its control is extremely difficult. For that reason, it is regarded as one of the difficult-to-control diseases among crop diseases.

Currently used control measures against this disease include the use of resistant varieties, application of organic substances, and
Examples include soil tillage, but they often do not show a stable control effect. In addition, soil fumigants such as chloropicrin and methyl bromide are used as chemical control methods. However, in recent years, the use of these agents causes pollution caused by an irritating odor, causes environmental pollution and destroys the ozone layer, and kills not only pathogenic bacteria in the soil but also useful microorganisms. There has been a demand for safe and highly effective control agents and control methods.

On the other hand, many microorganisms exist in natural soil and form an ecosystem by influencing each other. It has been clarified that many of these microorganisms have an antagonistic action against pathogenic bacteria. In order to provide a safe and effective control method, attempts to control this disease using these antagonistic soil microorganisms have been widely made.

[0006] As an example, for the bacterial wilt disease, a method using Pseudomonas putida (Pseudomonas fluorescen Pseudomonas fluorescen)
s) (Revista de Microbiologia (1989) V
ol.20: 18-26), a weakly pathogenic Pseudomonas solana strain of Pseudomonas solanasearum bacteriocin.
Cearum) (Japanese Patent Laid-Open No. 16579/1989)
And the like.

[0007]

In the examples using Pseudomonas putida or Pseudomonas fluorescens described above, these antagonistic bacteria show antibacterial activity against the wilt disease bacteria on the medium, and a short-term experiment in a greenhouse is conducted. The disease suppressive effect is recognized in. However, in most of the cases, the control effect was not observed in the actual field contaminated with the pathogenic bacterium, or the control effect was significantly reduced in the latter stage of cultivation. Therefore, so far, no plant having a satisfactory controlling effect until the later stage when used for solanaceous plants having a long cultivation period has been recognized.

Further, it was revealed that in the case of using the weakly pathogenic bacterial wilt disease and bacteriocin-producing OM2 strain, a temperature condition of 18 ° C. or higher is required for the roots of the treated strain to settle. (Journal of the Japanese Society for Plant Pathology (1989) 55: 511).
Generally, tobacco plants were transplanted in March, and the temperature conditions above 18 ° C could not be satisfied, so the number of treated bacteria was easy to decrease. Therefore, it was confirmed that the control effect of this disease is low or unstable.

As described above, at the present time, no practical microorganisms have been found which are stably established in the roots of plants of the Solanaceae family such as tobacco until the late stage of cultivation and show a stable and high control effect against this disease. It is not.

[0010] Therefore, the object of the present invention is to exert no adverse effect on the plant body, to stably establish in the root of the plant of the Solanaceae family such as tobacco until the late stage of cultivation, and further to be used in both greenhouse and field experiments. It is intended to provide a soil disease control agent having a high disease control effect (particularly, a control agent for tobacco wilt disease and Solanaceae plant wilt disease) and a soil disease control method thereof.

[0011]

[Means for Solving the Problem] The present inventors have further advanced the research and, unlike the microorganisms used in the conventional studies, isolated a microorganism effective for controlling the present disease. That is,
Bacteria belonging to Sphingomonas pasimobilis isolated from the tobacco root do not adversely affect the plant body and stably settled on the root until the late stage of cultivation of plants of the Solanaceae family such as tobacco, in both greenhouse and outdoor experiments. It was also discovered that the disease control effect is high. That is, the constitution of the present invention is shown below. (1) Sphingomonas paucim, which has the property of controlling soil diseases of Solanaceae plants
Obilis) -containing microorganisms and / or cultures thereof as active ingredients. (2) Sphingomona
The soil disease control agent for solanaceous plants according to (1) above, wherein the microorganism belonging to S. paucimobilis) is Sphingomonas pasimobilis A260 strain. (3) Sphingomona
The soil disease control agent for solanaceous plants according to (1) above, wherein the microorganism belonging to S. paucimobilis is Sphingomonas pasimobilis A266 strain. (4) The solanaceous plant according to any one of (1) to (3) above, wherein the soil disease is tobacco wilt caused by Pseudomonas solanacearum and wilting of solanaceous plants. Soil disease control agent.

(5) Any one of (1) to (4) above
5. A method for controlling soil diseases of Solanaceae plants, which comprises the step of introducing the soil disease controlling agent for Solanaceae plants described in 1) into the roots, cultivated areas and / or soil of the Solanaceae plants. (6) The method for controlling soil diseases of Solanaceae plants according to (5) above, wherein the soil diseases are tobacco wilt caused by Pseudomonas solanacearum and bacterial wilt of Solanaceae.

As patents relating to the genus Sphingomonas, the B-cell activator glycosphingolipid extracted from the genus fungus (JP-A-6-145189), biotin using the genus bacterium (JP-A-6-133790), malonyl It is used as a useful microorganism in terms of substance production, such as production of -7-aminocephalosporanic acid derivative (JP-A-6-46835). In addition,
Pseudomonas paucimobilis
, A strain that exhibits anti-filamentous activity on the medium against the pathogenic filamentous fungus Verticillium dahliae, which has many crops in the host range, has been isolated (Journal of Phytopathology (Berlin) (1994). 141-
1: 99-110). Thus, strains having antibacterial activity against the plant pathogenic fungi Verticillium and Fusarium have been isolated, but no examples have actually been used for disease control at the field level. Furthermore, as far as the inventor knows, bacteria belonging to Sphingomonas pasimobilis were used for disease control of plants, and further disease control of bacterial diseases,
Furthermore, no examples have been found used for controlling bacterial diseases of solanaceous plants.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the presence of a "microbe belonging to Sphingomonas pasimobilis" in the root part of a Solanaceae plant, a cultivated place and / or the soil thereof causes a soil disease of a Solanaceae plant (particularly tobacco). It has the property of controlling the wilt disease and the wilt disease of solanaceous plants. Furthermore, the microorganisms belonging to Sphingomonas pasimobilis having such a property can be used to determine the strain to be tested on the plant root, cultivated area and / or
Alternatively, by presenting it in the soil and selecting a strain recognized as having a property of controlling soil diseases of Solanaceae plants from the microorganisms belonging to the natural world or known Sphingomonas pasimobilis, it can be obtained with good reproducibility. it can. Examples of such a selection method include Example 1 described later.
And the methods recognized as equivalent thereto. On the assumption that the present invention is not limitedly interpreted by the following description, the reason why the soil disease of Solanaceae plants can be controlled by the above-mentioned microorganisms is that the above-mentioned microorganisms are rooted in the roots of the plants, and the plant pathogens of soil are To prevent intrusion,
It is considered that the plant may induce resistance of the soil to pathogens.

In the present invention, as the microorganism belonging to Sphingomonas pasimobilis having the above-mentioned properties, specifically, Sphingomonas pasimobilis A260 strain (hereinafter referred to as "A
260 strains) and Sphingomonas pasimobilis A266 strains (hereinafter referred to as "A266 strains").

In the present invention, the term "control" means not only the prevention of diseases but also the removal of diseases. In addition, the “root portion” means a portion in the soil or in the hydroponic solution that absorbs water and nutrients when the plant is cultivated. Examples of the Solanaceae plants to which the soil disease control agent and the control method of the present invention are applicable include, for example, tobacco,
Eggplants, tomatoes, bell peppers, potatoes, capsicum, pepino and the like can be mentioned, and they are applicable to host plants of wilt disease fungus.

The culture of Sphingomonas pasimobilis in the present invention does not require the use of a special culture medium, and may be any culture medium type and culture conditions. Examples of the medium include albumin medium (new edition Soil Microbial Experiments P380, Soil Microbiology Study Group), King B medium (J. Lab. Clin. Med. (1954) vol.44, 301-307), M
523 medium (Phytopathology (1954) vol.44, 969-976)
Alternatively, a general medium such as a meat extract medium may be used.
In addition to liquid medium, agar-containing slant medium, plate medium, etc. may be used. The cells can be grown by these cultures to obtain a desired amount of cells.

As the carbon source of the medium, any carbon source that the microorganism of the present invention can assimilate can be used. Specifically, in addition to sugars such as glucose, galactose, lactose, arabinose, mannose, and malt extract starch hydrolyzate, there are various synthetic or natural carbon sources that can be utilized by the microorganism. Similarly, as a nitrogen source, various synthetic or natural products usable by the microorganism can be used, including organic nitrogen-containing products such as peptone, meat extract, and yeast extract. Inorganic salts such as sodium chloride and phosphate, salts of metals such as calcium, magnesium and iron, and trace nutrients such as vitamins and amino acids can be added, if necessary, according to conventional methods for culturing microorganisms.

The culture can be carried out under aerobic conditions such as shaking culture, static culture, aeration culture and the like. The culture temperature is 20 to 30 ° C., preferably 25 to 28 ° C.
H is pH 5 to 8, preferably pH 6 to 7, and the culture period is 1 to 5 days, preferably 2 to 3 days.
In the soil disease controlling agent according to the present invention (hereinafter also simply referred to as “controlling agent”), when the microorganism is applied as a live bacterium,
The above-mentioned microorganisms are transplanted to the main field at a concentration of 10 ⁶ to 10 ¹⁰ , preferably 10 ⁷ to 10 ⁹ per 1 ml of water 7.
It is preferable that the root portion of the plant is applied once to a plurality of times from the day before to one month after the transplantation by performing a dipping treatment, an irrigation treatment, a perfusion treatment, or the like. In the case of the dipping treatment, the dipping time is 30 minutes to 3 hours, preferably 1
Time is 1 hour and 30 minutes. In the case of irrigation or perfusion treatment, 5 to 20 ml per seedling before transplantation,
After transplantation, it is preferable to apply 50 to 200 ml per seedling. Further, when it is applied as a culture of a microorganism, it is preferably applied as still containing bacterial cells, and its application time and application amount are appropriately determined according to the case of the above-mentioned viable bacteria.

Furthermore, according to a preferred embodiment of the present invention, the Solanaceae plant may be transplanted after the above-mentioned microorganism or a culture thereof is mixed or sprayed in soil. In this case, it is preferable that the time and amount of mixing or stirring / spraying are mixed so as to be 10 ⁵ cells or more per 1 g of soil between one month before and immediately before transplantation.

In the present invention, the culture of Sphingomonas pasimobilis means a culture suspension of a culture of the microorganism, viable bacteria, a culture filtrate, or an extract of an ingredient effective for controlling soil diseases. And

The soil disease controlling agent according to the present invention may be combined with a so-called carrier to form an agrochemical composition. Examples of preferable carriers include a water-soluble solvent optionally added with a pH buffer, a protective agent such as skim milk, and a powder agent including an auxiliary agent such as talc after freeze-drying, a granule agent, and a porous body such as vermiculite. Is mentioned. The soil disease controlling agent of the present invention can take any form of liquid, powder, tablets, sheets and the like. The soil disease controlling agent of the present invention may be combined with other active ingredients. Other active ingredients are not particularly limited, and examples thereof include insecticides, herbicides, fungicides and the like. Further, the soil disease controlling agent of the present invention may be a composition in combination with a soil conditioner, compost, fertilizer and the like. The amount of the microorganism and the culture thereof when formulated as a soil disease controlling agent, as well as the application time and the application amount, are appropriately determined according to the case of the above-mentioned viable bacteria.

[0023]

The present invention will be described below with reference to examples. However, the content of the present invention is not limited to these. Example 1 Separation / Selection Method of Sphingomonas pasimobilis Tobacco roots were collected from tobacco fields nationwide. Then, many bacterial strains were isolated from tobacco roots or rhizosphere.
Specifically, a healthy tobacco root was dug, the root was cut with scissors, and the attached soil was shaken off. About 1
The roots cut to the length of cm were placed in 10 ml of sterile distilled water, stirred with a mixer, and 1 platinum loop of the obtained suspension was taken,
Albumin medium (Egg albumin 0.25g, glucose
1.0 g, dipotassium phosphate 0.5 g, magnesium sulfate
Heptahydrate 0.2g, iron sulfate traces, agar 1000ml, pH 6.8 ~ 7.
0: New Edition Soil Microbial Experiments (1992) Soil Microbiology Study Group,
Yokendo or King B medium (Proteo-Septone No3 20.0 g, dipotassium phosphate 1.5 g, magnesium sulfate 1.5 g, glycerin 10.0 ml, distilled water 1000 ml: J.
Lab. Clin. Med (1954) Vol.44: 301-307). After culturing at 28 ° C for 3 days, the obtained single colony was -8
It was stored in a freezer at 0 ° C. In this way, a bacterium believed to be well-established on the root surface was obtained.

[0024] And, 1) bacteria themselves do not cause pathogenicity or adverse effects on crops, and 2) effectively suppress the occurrence of diseases caused by the wilt fungus in the field until the latter stage of cultivation. Useful strains were selected in greenhouse or field trials.

Specifically, as a method for evaluating the influence and effect on the plant body, 8 to 9 tobacco (cultivar: BY4) seedlings were tested, the bacterial strain was cultured in King B liquid medium, and then the culture solution was used. The roots of tobacco seedlings were irrigated and inoculated, and transplanted to a 4 inch pot containing soil. Furthermore, after inoculating the seedlings of the transplant seedlings with soil irrigation, the occurrence of wilting disease was regularly investigated in a greenhouse set at 30 ° C, and useful bacterial strains with high control effect were selected. Next, the strain having a high control effect in a greenhouse is cultured in King B liquid medium and then collected by centrifugation (× 10,000 g, 15
Min) and suspended in sterilized water at a concentration of 10 ⁹ CFU / ml, and then irrigated to inoculate 9 seedling roots of tobacco (cultivar: Tsukuba No. 2) to a field contaminated with wilt disease (concentration of contaminating bacteria 10 ³ CFU). / 1g dry soil)
, Transplanted in late April. After that, the disease was investigated until the latter stage of tobacco cultivation, and only the bacterial strains whose effects persisted until the latter stage were finally selected. As a result, A2, a useful bacterium from the root of tobacco (Michinoku No. 1), was found in Daio-mura, Hiraka-gun, Akita Prefecture.
60 and A266 strains were obtained. The A260 strain is an albumin medium and the A266 strain is a bacterium isolated by using a King B medium. Table 1 shows the bacteriological properties of the A260 strain obtained by this method and Table 1 shows the bacteriological properties of the A266 strain. The results are shown in Table 2.

[0026]

[Table 1]

[0027]

[Table 2]

The above A260 strain and A266 strain were mixed with Micr
obiol. Immunol. (1990) Vol.34 (2): 99-119, Sphingomonas paucimobi.
lis).

Example 2 A260 strain was shake-cultured in King B liquid medium at 28 ° C. for 2 days, and then adjusted to about 10 ⁹ CFU / ml. As tobacco seedlings (Bright Yellow 4), 20 9-leaf seedlings cultivated in a 36-planted vinyl chloride pot were used. For inoculation of the bacterial culture, 10 ml per strain was irrigated and inoculated to the original strain. The inoculated tobacco seedlings were grown for 12 hours in a greenhouse at 28 ° C and then
It was transplanted to a cm unglazed pot using fertilizer and cultivated in a greenhouse at 30 ° C. Two weeks after transplantation, the bacterial wilt disease (Pseudomonas
Solanacearum) solution (10 ⁶ CFU / ml) was irrigated and inoculated into the original strain in an amount of 20 ml per strain. As a control, instead of inoculation with the above-mentioned A260 strain, tobacco was irrigated and inoculated with the King B liquid medium alone in the same manner, and a tobacco was tested. Two weeks after the inoculation, the occurrence status of the wilt disease was investigated. As shown in Table 3, the degree of disease was set to 6 levels from 0 to 5, and the average disease index was calculated by the following formula, and the control rate was calculated. The disease incidence was calculated by dividing the number of diseased strains by the number of test specimens and multiplying by 100. Table 4 shows the results.

[0030]

[Table 3]

[0031]

[Table 4]

As is clear from the results shown in Table 4, the disease incidence was significantly lower in this bacterial treatment group than in the control group (t-test, 5% level). The average morbidity index was also significantly lower in the treated section (t-test, 1% level), and the control rate 2 weeks after the inoculation of dead bacteria was 63.1%.

Example 3 This bacterial strain A260 was cultured in King B liquid medium at 28 ° C. for 2 days with shaking, and then the cells were collected by centrifugation (10,000 × g, 10 minutes) and the concentration was 10 ⁹ CFU / ml in sterile water. Suspended in. Tobacco was grown in the same manner as in Example 2 and inoculated with this bacterial suspension in the same manner. In the same manner as in Example 2, the bacterial wilt disease bacteria were inoculated, and two weeks later, the onset of disease was investigated. As a control, a tobacco inoculated with only sterile distilled water instead of the suspension of this bacterial strain was used. The degree of disease onset was evaluated in the same manner as in Example 2, and the results are shown in Table 5.

[0034]

[Table 5]

As is clear from the results shown in Table 5, the disease incidence was significantly lower in this bacterial treatment group than in the control group (t-test, 5% level). The average morbidity index was also significantly lower in the treated group (t-test, 5% level), and the control rate 2 weeks after inoculation of the wilt disease bacteria was 60.0%.

Example 4 This bacterial strain A260 was cultured in King B liquid medium at 28 ° C. for 2 days with shaking, and then the cells were collected by centrifugation (10,000 × g, 10 minutes) and the concentration was 10 ⁹ CFU / ml in sterile water. Suspended in. The bacterial concentration was confirmed by King B plate medium. Tobacco seedling (Tsukuba 2
No.) was cultivated in a pot made of 36 PVC trees,
Nine-leaf seedlings of a size to be transplanted to the main field were tested. The bacterial suspension was inoculated by the following treatment. (1) Pre-transplantation treatment: One day before transplantation, bacterial suspension (10 ⁹ CFU / ml)
Was perfused with 10 ml of the original strain and then transplanted to the main field. (2) Pre-transplantation treatment / during soil treatment: Tobacco strains pre-transplanted as in (1) were cultivated and centrifuged in the same manner as in (1) to suspend the cells in distilled water (10 ⁸ CFU / ml), and 200 ml per plant was inoculated by soil irrigation at the time of soil donation. (3) Control group: Tobacco seedlings treated with the same method as in (1) before transplanting only sterile distilled water instead of the bacterial suspension were transplanted. Tobacco seedlings that had been pre-transplanted were cultivated in a greenhouse at 28 ° C for 12 hours and then placed in a field contaminated with wilt disease (10 ³ CFU / 1g dry soil).
I transplanted on the 14th of a month. The processing at the time of soiling was carried out on May 20. After transplanting, the plant was cultivated by a usual cultivation method, and the occurrence of wilt disease was periodically investigated in the same manner as in Example 2. The results are shown in Tables 6 and 7.

[0037]

[Table 6]

[0038]

[Table 7]

As is clear from the results shown in Tables 6 and 7, both the disease incidence and the average morbidity index were significantly lower (5% level) in the bacterial suspension treatment group than in the control group, and the control rate was also cultivated. It was stable until the second half. The variation in the number of surveys was due to the lack of strains in each test plot due to the damage caused by the viral disease.

Example 5 This bacterial strain A266 was shaken in King B liquid medium at 28 ° C. for 2 days.
About 10 after culturing ⁹Adjusted to CFU / ml. Tobacco seedling
(Bright Yellow 4) is made of 36 planted vinyl chloride
20 9-leaf seedlings cultivated in each pot were tested. Bacterial culture
The liquid was inoculated by irrigating 10 ml per strain to the original strain. Inoculation
The tobacco seedlings were cultivated in a greenhouse at 28 ° C for 12 hours,
It was transplanted to a clay pot with a diameter of 12 cm using fertilizer and stored in a greenhouse at 30 ° C.
Cultivated inside. Two weeks after transplantation, the bacterial wilt solution (10⁶CFU / m
L) was irrigated and inoculated into the original strain in an amount of 20 ml per strain. As a control
Instead of the A266 bacterial culture, King B liquid medium
Tobacco that was irrigated and inoculated to the tobacco strain
Was. Two weeks after the inoculation, the occurrence status of the wilt disease was investigated. Illness
The degree was investigated as described in Example 2 above, and the result was obtained.
Is shown in Table 8.

[0041]

[Table 8]

As is clear from the results in Table 8, the disease incidence was significantly lower in this bacterial treatment group than in the control group (t-test, 5% level). The average morbidity index was also significantly lower in the treated section (t-test, 1% level), and the control rate 2 weeks after the inoculation of dead bacteria was 70.8%.

Example 6 This bacterial strain A266 was shake-cultured in King B liquid medium at 28 ° C. for 2 days, and then the cells were collected by centrifugation (10,000 × g, 10 minutes), and the concentration was 10 ⁹ CFU / ml in sterile water. Suspended in. Tobacco was grown in the same manner as in Example 5 and inoculated with the bacterial suspension in the same manner.
In the same manner as in Example 5, the bacterial wilt disease bacteria were inoculated, and two weeks later, the onset of disease was investigated. As a control, a tobacco inoculated with only sterile distilled water in place of the bacterial strain A266 was used. The onset of disease was investigated in the same manner as in Example 2, and the results are shown in Table 9.

[0044]

[Table 9]

As is clear from the results shown in Table 9, the incidence of disease was significantly lower in this bacterial treatment group than in the control group (t test, 5% level). The average morbidity index was also significantly lower in the treated group (t-test, 5% level), and the control rate 2 weeks after the inoculation of the wilt bacterium was 72.0%.

Example 7 This bacterial strain A266 was cultured in King B liquid medium at 28 ° C. for 2 days with shaking, and then the cells were collected by centrifugation (10,000 × g, 10 minutes), and the concentration of 10 ⁹ CFU / ml was added to sterile water. Suspended in. The bacterial concentration was confirmed by King B plate medium. Tobacco seedling (Tsukuba 2
No.) was cultivated in a pot made of 36 PVC trees,
Nine-leaf seedlings of a size to be transplanted to the main field were tested. The bacterial suspension was inoculated by the following treatment. (1) Pre-transplantation treatment: One day before transplantation, bacterial suspension (10 ⁹ CFU / ml)
Was perfused with 10 ml of the original strain and then transplanted to the main field. (2) Pre-transplantation treatment / during soil treatment: Tobacco strains pre-transplanted as in (1) were cultivated and centrifuged in the same manner as in (1) to suspend the cells in distilled water (10 ⁸ CFU / ml), and 200 ml per plant was inoculated by soil irrigation at the time of soil donation. (3) Control group: Instead of the suspension of the bacterial strain A266,
Tobacco seedlings treated with the same method as in (1) before transplanting only sterile distilled water were transplanted. Tobacco seedlings that had been pre-transplanted had 12
After cultivating in a greenhouse at 28 ° C for an hour,
³ CFU / 1g dry soil) was transplanted on April 14th. The processing at the time of soiling was carried out on May 20. After transplanting, the plant was cultivated by a usual cultivation method, and the occurrence of wilt disease was periodically investigated in the same manner as in Example 2. The results are shown in Tables 10 and 11.

[0047]

[Table 10]

[0048]

[Table 11]

As is clear from the results in Tables 10 and 11, both the disease incidence and the average morbidity index in the bacterial suspension-treated group were significantly lower (5% level) than in the control group, and the control rate was also cultivated. It was stable until the second half. The variation in the number of surveys was due to a missing strain in each test plot due to the damage caused by the viral disease.

[0050]

EFFECTS OF THE INVENTION According to the present invention, the plant body is not adversely affected, the plant of the Solanaceae family such as tobacco is stably established in the rhizosphere until the latter stage of the cultivation, and the disease is observed in both greenhouse and field experiments. It is possible to provide a soil disease control agent for Solanaceae plants having a high control effect and a method for controlling the same.

Claims (6)

[Claims] 1. Sphingomonas pasimobilis (Sphingomonas) having the property of controlling soil diseases of Solanaceae plants
paucimobilis) and / or a culture thereof as an active ingredient. 2. A Sphingomonas pasimobilis (Sphin
The soil disease controlling agent for Solanaceae according to claim 1, wherein the microorganism belonging to gomonas paucimobilis is Sphingomonas pasimobilis A260 strain. 3. A Sphingomonas pasimobilis (Sphin
The soil disease controlling agent for Solanaceae according to claim 1, wherein the microorganism belonging to gomonas paucimobilis is Sphingomonas pasimobilis A266 strain. 4. The Solanaceae plant according to any one of claims 1 to 3, wherein the soil diseases are tobacco wilt disease and Solanaceae wilt disease caused by Pseudomonas solanacearum. Soil disease control agent. 5. A method comprising the step of introducing the soil disease control agent for solanaceous plants according to any one of claims 1 to 4 into a root part of a solanaceous plant, a cultivated place and / or its soil. For controlling soil diseases of solanaceous plants. 6. The method for controlling soil diseases of Solanaceae according to claim 5, wherein the soil diseases are tobacco wilt caused by Pseudomonas solanacearum and bacterial wilt of Solanaceae.