JP2011102278A - Method for controlling brassicaceous plant disease injury - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for controlling a Brassicaceae disease injury in which the controlling effect is high to clubroot which is a brassicaceous plant disease injury and there is not environmental pollution. <P>SOLUTION: An agent which includes Variovorax sp. CGF4526 as an active ingredient, and an agent which includes fluazinam (chemical name: 3-chloro-N-(3-chloro-5-trifluoromethyl-2-pyridyl)-α,α,α,-trifluoro-2,6-dinitro-p-toluidine) as an active ingredient are used. According to this, the onset to the disease injury of clubroot of a brassicaceous plant can be strongly controlled compared with a former one even when the disease level is high. Further, the controlling method has a dramatically high controlling effect compared with not only a chemical agent used now but also an independent bacterial strain or an independent agent. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an agent comprising, as an active ingredient, Variovorax sp. CGF4526, and fluazinam (chemical name: 3-chloro-N- (3-chloro-5-trifluoromethyl-2-pyridyl) The present invention relates to a method for controlling cruciferous plant diseases, characterized by bringing a cruciferous plant into contact with an agent containing () -α, α, α, -trifluoro-2,6-dinitro-p-toluidine) as an active ingredient.

  Plasmophorophora brassicae Woronin, a major soil disease of cruciferous plant diseases, is a soil filamentous fungal disease that occurs in many plants of cruciferous plants such as Chinese cabbage, cabbage, cauliflower, broccoli. Clubroot disease hinders the stable production of these cruciferous crops. As a symptom, knots are generated on the roots around 20 days after planting, and when infected from the beginning, no cabbage is formed with Chinese cabbage or cabbage. It can be seen that it cannot be obtained.

  Conventionally, the control agent which used microorganisms as an active ingredient has been developed, and until now, as a biological control method against the Brassicaceae plant clubroot, Bacillus genus bacteria (patent document 1), the acid borax genus bacteria There is a method (Patent Document 2). As a technique related to the present invention, there is a method using a genus Varioborax (Patent Document 3).

  On the other hand, fluazinam is an active ingredient of an agricultural and horticultural fungicide and is a compound described in Patent Document 4.

  Common dosage forms of bactericides containing fluazinam as an active ingredient include wettable powders and suspensions. Patent Document 5 contains fluazinam alone or fluazinam and other bactericidal active ingredients. A wettable powder has been reported. Further, Patent Document 6 reports that a high control effect against clubroot can be obtained by direct irrigation treatment and immersion treatment on the roots before planting of cruciferous crops. Fluazinam is mentioned as an example of a clubroot controlling agent. Further, Patent Document 7 discloses that an excellent control effect is exhibited by mixing a bactericidal component such as fluazinam and a fertilizer component such as phosphorous acid. In Patent Document 8, fluazinam and poly-1- An agricultural fungicide containing p-menten (or fluazinam and di-1-p-menten) as an active ingredient is disclosed.

JP 11-335217 A JP 2003-342109 A JP 2005-137330 A European Patent No. 031257 Japanese Patent No. 3384882 Japanese Patent No. 2582045 JP 2000-264802 A JP 2006008515 A

  An object of the present invention is to provide a method for controlling a cruciferous plant disease that is stable and has a high control effect, high safety, and is free from environmental pollution against a clubroot disease, which is a cruciferous plant disease.

  As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention have effectively used the Varioborax sp. CGF4526 strain against root-knot disease, which is a cruciferous plant disease such as cruciferous cabbage and cabbage. Agents included as components, and fluazinam (chemical name: 3-chloro-N- (3-chloro-5-trifluoromethyl-2-pyridyl) -α, α, α, -trifluoro represented by the formula [1] -2,6-dinitro-p-toluidine)

The present invention was completed by finding a control method having a high control effect by bringing a cruciferous plant into contact with an agent containing as an active ingredient.

That is, this invention provides the control method of the cruciferous plant disease described in the following [invention 1]-[invention 6].
[Invention 1]
A method for controlling a cruciferous plant disease, comprising the step of contacting a cruciferous plant with an agent comprising a Variovorax sp. CGF4526 as an active ingredient, A method for controlling a cruciferous plant disease, comprising a step of bringing an agent comprising an active ingredient into contact with a soil for planting the cruciferous plant.
[Invention 2]
The contact with cruciferous plants is carried out by mixing or irrigating the seedling culture medium at the time of sowing, or immersing or irrigating the seedlings before planting, with an agent containing the Varioborax bacterium CGF4526 as an active ingredient. A method according to invention 1, characterized in that
[Invention 3]
The method according to invention 1, wherein the contact with soil is carried out by spraying or mixing the agent containing fluazinam represented by formula [1] as an active ingredient on the soil surface.
[Invention 4]
A method for controlling cruciferous plant diseases, in which an agent containing Variovorax sp. A step of dip treatment or irrigation, and a step of spraying or admixing the agent containing fluazinam represented by the formula [1] as an active ingredient on the soil in which the cruciferous plant is planted, or mixing the soil. Control method.
[Invention 5]
The method according to any one of inventions 1 to 4, wherein the cruciferous plant disease is a clubroot disease.
[Invention 6]
The method according to any one of inventions 1 to 5, wherein the cruciferous plant is Chinese cabbage, cabbage, radish, cauliflower, broccoli, chingensai, or komatsuna.

  As described above, in the method described in Patent Document 3, when the varioborax bacterium CGF4526 strain was used alone, the control effect was sometimes weak (see Comparative Example). However, it was found that the control effect was remarkably improved and a high control effect could be stably obtained by combining the Cvariobacterium genus CGF4526 and fluazinam. The term “combining” as used herein refers to “combining” a single agent of each of the varioborax genus CGF4526 and fluazinam without mixing them.

  For example, as shown in a comparative example described later, when the varioborax genus CGF4526 strain or fluazinam is individually acted on clubroot of a cruciferous plant, the control effect is small. In addition, when the two agents are mixed, the function as a control agent for fluazinam and varioborax bacteria CGF4526 and their respective control agents does not occur, and a control effect is hardly obtained.

  In the present invention, it was found that by combining the above-mentioned two agents, there was a specific improvement, that is, a synergistic effect far exceeding the expected effect when only two agents were applied alone.

  The details of the mechanism are unknown, but it is expected that the antibacterial properties of the two agents against the clubroot bacteria are involved.

  It has been widely known that fluazinam and barioborax bacteria CGF4526 have a controlling effect against clubroot of cruciferous plants. However, it is known that the combination of fluazinam with the varioborax bacterium CGF4526, which had a weak control effect in the case of mania, has a much higher control effect even in the case of mania. It was not done.

  The method for controlling clubroot of the cruciferous plant in the present invention can strongly suppress the occurrence of root-knot disease even when the degree of onset is higher than the conventional one, and further, a single strain or a single There is an effect of having a remarkably high control effect compared with the agent.

  In addition, the control method of the present invention is an extremely useful control method without causing environmental pollution and without causing phytotoxicity to cruciferous plants.

FIG. 1 is a comparison of control values in Examples and Comparative Examples. Here, A represents the Varioborax sp. GCF4526 strain, and B represents the chemical F.

  The present invention is described in detail below.

  The object of the present invention is a method for controlling cruciferous plant diseases, comprising an agent containing the Variovorax sp. CGF4526 as an active ingredient, and fluazinam represented by the formula [1] as an active ingredient A method for controlling cruciferous plant diseases, which comprises contacting a cruciferous plant with an agent (hereinafter referred to as “chemical agent F” in the present specification).

  First, the CGF4526 strain will be described.

  CGF4526 is an antibacterial activity against about 7000 strains of bacteria isolated and collected from rice and vegetables, Fusarium oxysporum and Verticillium daliae, and pots using Chinese cabbage seedlings. It is the strain obtained as a result of selection by the test. The strain is deposited with the Patent Organism Depositary, National Institute of Advanced Industrial Science and Technology, and the following deposit number is obtained and disclosed in Patent Document 3.

Variovorax sp. CGF4526: FERM BP-10160
Next, the chemical agent F will be described. The chemical agent F is a substance already known as an agricultural fungicide, as mentioned in the above patent document. Chemical agent F has antibacterial ability against pathogenic fungi of various plants, and has high control ability against clubroot of cruciferous plants, powdery scab of potato and the like. In addition, it exhibits antibacterial activity against gram-positive bacteria against bacteria and the like.

  Regarding the chemical agent F, for example, it can be produced by the method disclosed in Patent Documents 5 to 8 or commercially available.

  Plants targeted for plant diseases in the present invention are cruciferous plants such as Chinese cabbage, cabbage, radish, cauliflower, broccoli, chingensai, and komatsuna, but are not limited thereto. Further, the cruciferous plant diseases to be targeted are root-knot diseases, but besides this, wilt disease, yellowing diseases and the like are also target diseases.

The method for culturing, immobilizing, formulating, and preparing the CGF4526 strain can be performed by a known method disclosed in Patent Document 3, and will be described below with specific examples. The medium is not particularly limited as long as the CGF4526 strain grows, and any natural or synthetic medium can be used as long as it contains a carbon source, a nitrogen source, and an inorganic substance capable of growth. be able to. Examples of the medium include 802 medium, bouillon medium, King B medium, PS medium, PDB medium, and the like. After culturing and growing in the above medium at 15 to 42 ° C., preferably 28 to 35 ° C. for 10 to 35 hours, the cells are concentrated by a centrifuge or a membrane concentrator, and the medium components are removed. . By this operation, the concentration of each bacterial cell is usually concentrated to about 1 to 50 × 10 ¹⁰ cfu / ml. Then, a protective agent consisting of a saccharide, sodium glutamate, and a sodium phosphate buffer is added to the wet cells and vacuum dried. In order to maintain the survival rate of bacteria, it is preferable to pre-freeze the microbial cells mixed with the protective agent before vacuum drying and then vacuum-dry them while they are frozen. In addition, a protective agent may be mixed with a microbial cell in the state of aqueous solution, and may be mixed with solid.

  Next, immobilization will be described. Immobilization refers to an operation of adding a protective agent to the above-mentioned cultured bacteria and vacuum drying. There is no particular limitation on immobilization, and the protective agent used for immobilization is a saccharide consisting of one or more of sucrose, fructose, glucose and sorbitol, mixed with the cells, vacuum dried or freeze-vacuum. It can carry out by drying by methods.

  Next, formulation will be described. Formulation refers to an operation in which a carrier is mixed with the above-described immobilized cultured cells to prepare a formulation.

  The CGF4526 strain may be used as it is after culturing, but it may be prepared as a preparation by immobilizing the cells and mixing them with a solid (powder or granule, wettable powder) or liquid carrier. Well, those skilled in the art can adjust accordingly.

  Carriers used in the preparation of pharmaceutical preparations include mineral powders such as talc, clay, calcium carbonate, diatomaceous earth, peat moss, polymer compounds such as polyvinyl alcohol, natural polymer compounds such as xanthan gum and alginic acid, etc. There is.

Next, a specific bacterial concentration in the CGF4526 strain will be described. The fungus concentration varies depending on the control method for its own cruciferous plant. For example, when contacting the seedling culture medium at the time of sowing as it is, the bacterial concentration is usually 10 ⁵ cfu / g to 10 ¹¹ cfu / g, preferably 10 ⁶ cfu / g to 10 ⁹ cfu for each strain. / g, more preferably 10 ⁷ cfu / g to 10 ⁹ cfu / g.

In addition, the CGF4526 strain can be poured into a seedling culture medium as it is after diluting with water. In this case, the bacterial concentration is usually 10 ⁵ cfu / ml to 10 ¹¹ cfu / ml, preferably 10 ⁶ cfu / ml to 10 ⁹ cfu / ml, more preferably 10 ⁷ cfu / ml for each strain. ml to 10 ⁹ cfu / ml.

On the other hand, the CGF4526 strain of the genus Varioborax can be made into the above-mentioned solid (powder or granule, wettable powder) or liquid preparation and then contacted with the seedling culture medium at the time of sowing. In this case, in the case of a solid preparation (powder or granule), the bacterial concentration is usually 10 ⁵ cfu / g to 10 ¹¹ cfu / g, preferably 10 ⁶ cfu / g to 10 ⁹ cfu / g, more preferably 10 ⁷ cfu / g to 10 ⁹ cfu / g.

In the case of a solid preparation (wettable powder), it is usually 10 ⁷ cfu / g to 10 ¹² cfu / g, preferably 10 ⁸ cfu / g to 10 ¹¹ cfu / g, more preferably 10 ⁹ cfu / g. g to 10 ¹¹ cfu / g.

  In addition, regarding the case where a liquid formulation is contacted with the seedling culture medium at the time of sowing, it can be adjusted in the same concentration range as the above-mentioned solid formulation (powder or granule).

In addition, when the CGF4526 strain is made into a solid (wettable powder, powder or granule) or liquid formulation and then diluted with water to the seedling culture medium at the time of sowing, the concentration of the bacteria is the solid formulation (powder) or in the case of granules) is normally ^{10 5 cfu / ml~10 11 cfu /} ml, preferably ^{10 6 cfu / ml~10 9 cfu /} ml, more preferably 10 ⁷ cfu / ml~10 ⁹ cfu / ml.

In the case of a solid preparation (wettable powder), it is usually 10 ⁷ cfu / ml to 10 ¹² cfu / ml, preferably 10 ⁸ cfu / ml to 10 ¹¹ cfu / ml, more preferably 10 ⁹ cfu. / ml to 10 ¹¹ cfu / ml.

  In addition, regarding the case where the liquid preparation is diluted with water to the seedling culture medium at the time of sowing, it can be adjusted in the same concentration range as the solid preparation (powder or granule).

  Next, a method for adjusting the concentration of the CGF4526 strain will be described.

  First, when the CGF4526 strain is directly brought into contact with the seedling culture soil at the time of sowing, the strain is adjusted by contacting with the seedling culture soil so as to be in the above-mentioned concentration range.

  Next, when the CGF4526 strain is diluted as it is with water in the seedling culture medium at the time of sowing, it is first diluted with water so that the concentration of the CGF4526 strain falls within the aforementioned concentration range. After that, pour it into the seedling culture soil at the time of sowing.

    On the other hand, when preparing the CGF4526 strain as a solid or liquid preparation, after adding and adjusting the preparation so as to be within the above-mentioned concentration range, contact with the seedling culture medium at the time of sowing, or dilute with water and sow at the time of sowing. Pour it into the seedling culture soil.

  The application rate in the case of applying the chemical agent F will be described. The application rate of the chemical agent F varies depending on the type of target disease, soil conditions (moisture, pH), organic matter content, and weather conditions. When applying the chemical agent F as a soil treatment agent, the amount of the active ingredient is usually 50 g to 500 g / 10a, preferably 50 g to 400 g / 10a, more preferably 70 g to 200 g / 10a.

  In addition, the "active ingredient amount" said here refers to the component amount of only the fluazinam in the chemical agent F. For example, the application rate varies greatly depending on the application form (formulation). In that case, those skilled in the art can adjust appropriately so that it may become the range of the above-mentioned active ingredient amount.

  Next, a method for controlling cruciferous plant diseases will be described.

  In general, for the production of cruciferous plants such as Chinese cabbage, seedling trays are filled with seedling culture soil and sown. After raising the seedlings for 3 to 5 weeks, the plants are planted in a field (field). The term “fixed planting” as used herein means that the plant is transferred from the nursery to the field and planted in this manner.

As the control method of the present invention, the following control methods,
i) Contacting CGF4526 strain with Brassicaceae plants ii) Contacting chemical agent F with soil in which Brassicaceae plants are planted.

  First, i) will be described. As a treatment method, the CGF4526 strain can be treated by mixing or irrigating the seedling culture medium at the time of sowing, or by irrigating the seeds before and after sowing. Further, it is possible to dilute with water and soak or pour seedling roots before planting in the diluted solution, or pour into seedlings during or just before planting.

  For example, when the seedling is treated or pre-planted, that is, mixing or irrigating the seedling culture medium at the time of sowing, or immersing or irrigating the seedling before planting is more efficient for colonization of the fungus on the roots. Therefore, this is one of the preferred embodiments of the present invention.

  Here, when performing the mixing process to the seedling culture soil, 1 g or more per 1 L of soil is mixed and stirred so as to be uniform.

  On the other hand, the CGF4526 strain can be made into a solid or liquid preparation and then treated by the treatment method described above.

  Next, the processing method ii) will be described. After the treatment of i), the chemical agent F is brought into contact with the soil (field or the like) to be planted. That is, it can be carried out by spraying on the surface of the soil or by mixing with the soil (mixing with the entire surface of the soil, mixing with the cropping soil).

  The processing methods i) and ii) are not greatly limited in the number of processing. However, for example, it is preferable to perform the processing method i) a plurality of times, so that the control effect can be further enhanced. One of the methods. For example, as shown in the examples described later, after pouring CGF4526 strain into the seedling culture medium at the time of sowing, further pouring into the seedlings before planting can be carried out multiple times, so that the main bacteria to the root This is one of the particularly preferred embodiments since fixing of the toner becomes more efficient.

  As described above, in the present invention, by using an agent containing CGF4526 strain as an active ingredient and an agent containing chemical agent F as an active ingredient, a high control effect can be exhibited even in soil with a high degree of disease.

  EXAMPLES Next, examples will be shown, but the present invention is not limited to the following examples.

The composition of the medium used in the examples is shown below.
Bouillon medium: meat extract 3g, peptone 10g, NaCl 15g, water 1L, pH7.0
Moreover, about the chemical agent F, what was marketed generally was used.

Control test against Chinese cabbage root-knot disease (pot test)
Using the preparation of CGF4526 strain, we investigated the disease-inhibiting effect against Chinese cabbage root-knot disease. The preparation of the preparation was prepared by appropriately diluting the cells cultured and dried by the above-mentioned method with a carrier (a bulking agent) and adjusting the concentration of the bacteria to 2 × 10 ¹⁰ cfu / g.

  The preparation was diluted 200 times and poured into soil (128-hole nursery tray, 60 cm × 30 cm) seeded with Chinese cabbage seeds (variety: Satobuki 613). Then, after raising the seedling for about 3 weeks, it was planted in the contaminated soil. On the other hand, the same irrigation treatment was performed again on the day before planting, that is, before planting, and the plant was also planted on contaminated soil.

  On the other hand, the chemical agent F was mixed with contaminated soil at a rate of 40 kg / 10a immediately before the Chinese cabbage planting.

  As the contaminated soil, field soil was used in which Chinese cabbage roots (with root knots) affected by Chinese cabbage root koji were homogenized and mixed. After 27 days, the presence or absence of disease was investigated and the control effect was determined. The results are shown in Table 1.

The severity of clubroot disease was evaluated by calculating the disease strain rate, the disease severity, and the control value from the state of the root bump.
Root incidence index 0; healthy, 1; slight root nodule attachment on root root, 2; many root nodule attachments on branch root, or root nodule attachment found on main root, 3; main root Adhere large root bumps or die.
Disease rate (%) = 100 × {(number of diseased strains) ÷ (total number of surveyed strains)}
Disease severity = 100 × {Σ (index value) × (number of individuals corresponding to each index)} ÷ {3 × (number of surveyed seedlings)})
Control value = 100 × {(morbidity in untreated area) − (morbidity in treated area)} ÷ (morbidity in untreated area)

As a result, when the disease severity was severe, when the Varioborax sp. CGF4526 strain and the chemical agent F were used in combination, a higher control value was obtained as compared with Comparative Examples 1 and 2 described later.
[Comparative Example 1] Control test against Chinese cabbage root-knot disease (pot test)
The same procedure as in Example 1 was conducted except that the CGF4526 bacterium belonging to the genus Barrioborax was used alone. Similarly, the bacterial concentration of the suspension was 1 × 10 ⁸ cfu / ml.

  As in Example 1, the degree of root-knot disease was evaluated by calculating the disease strain rate, disease severity, and control value from the state of the root-kump.

[Comparative Example 2] Control test against Chinese cabbage root-knot disease (pot test)
An example in which the chemical agent F was used alone was shown. The ratio applied to the contaminated soil was similarly 40 kg / 10a.

  As in Example 1, the degree of root-knot disease was evaluated by calculating the disease strain rate, disease severity, and control value from the state of the root-kump.

Claims (6)

A method for controlling a cruciferous plant disease, the method comprising contacting a cruciferous plant with an agent comprising a Variovorax sp. CGF4526 as an active ingredient, and a 3- Chloro-N- (3-chloro-5-trifluoromethyl-2-pyridyl) -α, α, α, -trifluoro-2,6-dinitro-p-toluidine

A method for controlling a cruciferous plant disease, comprising a step of bringing an agent containing the cruciferous plant as an active ingredient into contact with a soil for planting the cruciferous plant. The contact with cruciferous plants is carried out by mixing or irrigating the seedling culture medium at the time of sowing, or immersing or irrigating the seedlings before planting, with an agent containing the Varioborax bacterium CGF4526 as an active ingredient. The method of claim 1, wherein: The contact with soil is represented by the formula [1] 3-chloro-N- (3-chloro-5-trifluoromethyl-2-pyridyl) -α, α, α, -trifluoro-2,6- The method according to claim 1, wherein the method is carried out by spraying or mixing the agent containing dinitro-p-toluidine as an active ingredient on the soil surface. A method for controlling cruciferous plant diseases, in which an agent containing Variovorax sp. Step of dipping or pouring, and 3-chloro-N- (3-chloro-5-trifluoromethyl-2-pyridyl) -α, α, α, -trifluoro-2 represented by the formula [1] , 6-Dinitro-p-toluidine

A method for controlling a cruciferous plant disease, comprising a step of spraying or admixing an agent containing a cruciferous plant as an active ingredient on the soil in which the cruciferous plant is planted. 5. The method according to claim 1, wherein the cruciferous plant disease is a clubroot disease. The method according to any one of claims 1 to 5, wherein the cruciferous plant is Chinese cabbage, cabbage, radish, cauliflower, broccoli, chingensai, or komatsuna.