JP2009007269A - Agent and method for controlling tomato disease - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an agent for controlling bacterial canker disease damage of a Solanaceae plant, containing Erwinia carotovora subsp. carotovora bacteria having high antagonistic activity to Clavibacter michiganensis bacteria of pathogenic bacteria causing the canker disease to a tomato or the like, as an active ingredient, and to provide a controlling method. <P>SOLUTION: The agent for controlling the bacterial canker disease damage of the Solanaceae plant contains the non-pathogenic Erwinia carotovora subsp. carotovora bacteria as an active ingredient. As a result, the canker disease damage of the Solanaceae plant caused by the Clavibacter michiganensis can be controlled in high controlling effects by the Erwinia carotovora subsp. carotovora bacteria. The invention is the method using live bacteria as an organism-controlling method, and provides a safe method for controlling the plant disease damage without causing chemical injury. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a control agent and a control method for scab disease of solanaceous plants, characterized by containing an avirulent Erwinia carotovora subsp. Carotovora bacterium as an active ingredient.

  Bacteria belonging to Clavibacter mysiganensis, Sabspii michiganensis are known as diseases against solanaceous plants, ie, scab, and cause enormous diseases in crops such as tomatoes. For example, in the case of tomato scab, when the bacterial disease occurs, bird-like spots appear on the fruit, the leaves turn yellow, the leaflets roll up, the lower leaves hang down with the petiole, and the whole leaves eventually Browning dies.

  As a conventional method for controlling bacterial diseases in general, for example, there are chemical agents such as copper agents such as copper sulfate and basic copper chloride, and streptomycin. There is a fear. There are also environmental problems such as killing useful microorganisms.

  Therefore, a method for controlling these plants using microorganisms has been developed against scab. For example, Patent Document 1 discloses a method capable of effectively controlling plant diseases such as scab by treating seeds with microorganisms such as Trichoderma and Pseudomonas, and aminobutyric acid, oligosaccharides, and phenol compounds. Has been.

  Further, Patent Document 2 discloses a method for controlling the scab of solanaceous plants using the anti-scab fungus Ku17 (FERM P-18177) or Ku44 (FERM P-18178).

  On the other hand, as a technical document related to the present invention, a method for controlling diseases using Erwinia bacteria is described in Patent Documents 3-12, Chinese cabbage, cabbage, celery, lettuce, carrot, radish, wasabi, potato, tobacco, tomato. , Against soft rot of plants such as cyclamen, against bacterial wilt of rice seeds in patent document 13, and black rot of cruciferous crops such as cabbage, radish, broccoli, Chinese cabbage in patent documents 14-15 It has been reported that the disease can be controlled.

As for scabs such as tomatoes caused by Clavibacter michiganensis, no control by Erwinia carotovora subsp. Carotovora bacteria has been reported.
JP 2003-034607 A JP 2002-223747 A Japanese Examined Patent Publication No. 6-92286 Japanese Patent Publication No. 6-81595 Japanese Patent Publication No. 6-81594 Japanese Examined Patent Publication No. 6-38746 Japanese Patent Laid-Open No. 4-311391 JP-A-5-915 JP-A-6-56614 JP-A-6-56615 Japanese Patent Laid-Open No. 10-327849 Japanese Patent Laid-Open No. 11-290065 JP-A-6-087716 JP-A-6-305927 Japanese Patent Laid-Open No. 7-23621

  The present invention is not a phytotoxicity or fouling of leaves like a chemical agent, and is highly safe for the environment, and has a high control effect using a bacterium such as a tomato plant such as a tomato plant. It is an object of the present invention to provide a control agent and a control method for mildew diseases.

  As a result of intensive studies, the present inventors have found that non-pathogenic Erwinia carotovora subsp. Carotovora bacteria can suitably control tomato scab caused by Clavibacter mysiganensis, leading to the present invention. .

  By using this bacterium, not only when the disease severity is small to moderate, but also when the disease severity is severe (ie, the severity of epilepsy), a very high control effect (for example, Example 1-2 described later) And obtained practically advantageous knowledge.

  Moreover, when the control agent in this invention was made to contact the leaf, stem, etc. of a plant, the knowledge that a certain specific processing method was especially preferable was also acquired.

That is, this invention provides the control agent and control method for control of a solanaceous plant disease described in the following [invention 1]-[invention 7].
[Invention 1] A control agent for controlling a solanaceous plant disease characterized by comprising an avirulent Erwinia carotovora subsp. Carotovora bacterium as an active ingredient.
[Invention 2] The control agent according to Invention 1, wherein the non-pathogenic Erwinia carotobola subsp. Carotobola bacterium is at least one selected from CGE6M14, CGE6M16, CGE10M2, CGE11M5, and CGE234M403.
[Invention 3]
The control agent according to invention 1 or 2, wherein the solanaceous plant disease is a scab.
[Invention 4]
A method for controlling a scab disease of a solanaceous plant, comprising bringing the control agent according to any one of inventions 1 to 3 into contact with a solanaceous plant.
[Invention 5]
The control agent according to any one of the inventions 1 to 3, wherein the control agent according to any one of the inventions 1 to 3 is mixed with water to form a suspension, and the solanaceous plant is immersed in the suspension. Method.
[Invention 6]
The control agent according to any one of the inventions 1 to 3 is mixed with water to form a suspension, and the suspension is sprayed onto a solanaceous plant, and control of a sore disease of the solanaceous plant is provided. Method.
[Invention 7]
The method according to any one of Inventions 4 to 6, wherein the solanaceous plant is a tomato.

  According to the present invention, it has become possible for the Erwinia carotobola subsp. Carotobola bacteria to control the scab disease of solanaceous plants caused by Krabibacter mysiganensis with high control ability. In addition, the present invention is a method of using live bacteria as a biological control measure, and provides a safe method for controlling plant diseases that does not require chemical agents currently used and has no phytotoxicity.

  The present invention is described in detail below. The present invention relates to a control agent against a scab of a solanaceous plant characterized by containing an avirulent Erwinia carotovora subsp. Carotovora bacterium as an active ingredient, and a solanaceous plant using the same. This is a method for controlling squamous diseases.

  Here, non-pathogenic Erwinia carotobola subsp. Non-pathogenic Erbinia carotobola subsp. Carotobola bacteria are bacteria that control diseases (soft rot) that affect a wide range of plants, including cruciferous crops such as Chinese cabbage.

Among them, as shown below, five strains were found to be particularly effective in controlling soft rot, and the corresponding strains were deposited at the National Institute of Advanced Industrial Science and Technology Patent Organism Depositary Center. It is disclosed in Patent Document 3-15.
Elvinia Carotobola Subspi Carotobola CGE6M14 FERM P-10998
Elvinia Carotobola Subspi Carotobola CGE6M16 FERM P-10999
Elvinia Carotobola Subspi Carotobola CGE10M2 FERM P-11000
Elvinia Carotobola Subspi Carotobola CGE11M5 FERM P-11001
Elvinia Carotobola Subspi Carotobola CGE234M403 FERM BP-4328
The present inventors have found that these five strains are excellent as an Erwinia carotobola subsp. Carotobola bacterium for controlling the scab disease of the solanaceous plant that is the subject of the present invention.

  Among these bacteria, the Erwinia carotobola subspica carotobola strain CGE234M403 (FERM BP-4328) is particularly preferably used because it obtains a high control effect against scab diseases of solanaceous plants.

  Since this bacterium has an antagonistic activity against the pathogenic bacterium Clavibacter mysiganensis bacteria, it can exert a high control effect against the scab that is a bacterial disease of solanaceous plants such as tomatoes. Non-pathogenic live strains have been obtained by carrying out mutation treatment of CGE234 strain selected as a strain that secretes bacteriocin exhibiting antibacterial activity against many soft rot strains.

  This fungus has particularly good fixability to roots, stems and leaves of solanaceous plants.

  In the present invention, the plant targeted for plant diseases of the control agent containing a non-pathogenic Erbinia carotobola subsp. Carotobola bacterium as an active ingredient is a solanaceous plant such as tomato, eggplant, pepper, etc. Is preferably used because it can be suitably controlled against scab.

  Next, the culture and culture medium of non-pathogenic Erwinia carotobola subspica carotobola bacteria will be described.

Any natural or synthetic medium can be used as long as it is a medium appropriately containing a carbon source, a nitrogen source and an inorganic substance capable of growing. Examples of the medium include 802 medium, bouillon medium, King B medium, PS medium, and PDB medium. After culturing and growing in the above medium at 15-42 ° C, preferably 28-35 ° C for 10-35 hours, concentrating with a centrifuge or membrane concentrator to collect the medium, and removing the medium components . By this operation, the concentration of each bacterial cell is usually concentrated to about 1 to 50 × 10 ¹⁰ cfu / ml.

  Next, a protective agent such as saccharide 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 an individual | organism | 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 the immobilization, and it can be carried out after cultivation of non-pathogenic Erbinia carotobola subsp. .

  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 non-pathogenic Erwinia carotobola subspiso carotobola bacterium used in the present invention may be used as it is after culturing, but it may be solid (powder or granule, wettable powder) or liquid after immobilizing the cells. It can be mixed with a carrier and prepared as a preparation. Carriers used in the preparation of the preparation include mineral powders such as talc, clay, calcium carbonate, diatomaceous earth, peat moss, and polymer compounds such as polyvinyl alcohol, natural polymer compounds such as xanthan gum and alginic acid, etc. There is.

  Next, the control method for the scab disease of solanaceous plants such as tomatoes using the non-pathogenic Erbinia carotobola subsp.

  In general, production of solanaceous plants such as tomatoes is carried out by filling seedling trays with seedling culture soil. 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.

  The Erwinia carotobola subsp. Carotobola bacterium of the present invention exhibits an effect as an antibacterial agent by being brought into contact with the leaves or stems of plants subject to scabs such as tomatoes.

For example,
i) Leave the bacterium as it is or make the bacterium into a solid or liquid preparation, and then add water to make a suspension.
ii) Next, after raising seedlings for about 2 to 5 weeks, the solanaceous plant before planting is immersed in the suspension of i), or the suspension of i) is inoculated on the leaves and stems, Alternatively, spraying treatment is performed on the entire seedling. By performing the above treatment method, it is possible to suitably control the scab.

  In Example 1 of the present invention, the tomato is immersed in a bacterial suspension prepared by diluting Erwinia carotobola subsp. Carotobola bacteria and the pathogenic fungus Clavibacter mysiganensis with water. Carotobola subspi The bacterial suspension prepared with water of the carotobola and the pathogen Clavibacter michiganensis is inoculated into the tomato using a syringe, and in Example 3, the tomato is treated with the Erwinia carotobola It is one of the particularly preferred embodiments that the dispersal treatment of the carotobola (Erwinia carotovora subsp. Carotovora CGE234M403) and the pathogenic fungus Clavibacter michiganensis is one of the preferred embodiments.

  This control agent can be treated not only before planting but also at the time of planting or after planting, and can be combined with immersion treatment, inoculation treatment, and spraying treatment, respectively, and can be adjusted as appropriate by those skilled in the art. .

  Next, a method for adjusting the concentration of non-pathogenic Erwinia carotobola subsp.

  First, the concentration of the non-pathogenic Erwinia carotobola subsp. Carotobola bacteria is adjusted as it is or with water so as to be in the concentration range described later.

  On the other hand, when making bacteria into a solid or liquid preparation, after adding and adjusting the preparation so that it will be in the concentration range described later, it is diluted as it is or with water and brought into contact with the seedlings 2 to 3 days after seedling raising. .

  Next, a specific bacterial concentration in bacteria will be described.

First, the non-pathogenic Erbinia carotobola subsp. Carotobola bacterium, when this bacterium is contacted 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 / g, more preferably 10 ⁷ cfu / g to 10 ⁹ cfu / g.

In addition, this bacterium can also be diluted with water with respect to the seedling culture medium as it is to make a suspension. The bacterial concentration in this case 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 to 10 ⁹ cfu / ml. It is.

On the other hand, after the non-pathogenic Erbinia carotobola subspica carotobola bacterium is made into the above-mentioned solid (powder or granule, wettable powder) or liquid preparation, it can be contacted with the seedling culture soil at the time of sowing. In this case, in the case of a solid preparation (powder or granule), it 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.

  Thus, in the present invention, a high control effect can be exhibited even in soil with a high degree of disease by using a control agent containing a non-pathogenic Erbinia carotobola subspicarotobola bacterium as an active ingredient.

  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

Adjust the Erwinia carotovora subsp. Carotovora subsp. CarotovoraCGE234M403 with water to a bacterial concentration of 4 × 10 ⁷ cfu / ml, then dilute the pathogenic fungus Clavibacter michiganensis with water respectively. What was adjusted to 2 × 10 ⁶ cfu / ml, 2 × 10 ⁷ cfu / ml, and 2 × 10 ⁸ cfu / ml was mixed with the above-mentioned Erwinia carotobola subsp. Carotobola bacteria to prepare three types of suspensions.

  Next, the tomatoes (variety Momotaro) at the main leaf 1-2 leaf stage were extracted from the nursery bed, immersed in each of the three types of bacterial suspensions for 30 minutes, and then transplanted to sterilized soil. Thereafter, the disease was investigated 3 weeks later.

  Next, Table 1 also shows the results of using the treated group (non-treated group) of the pathogenic fungus Clavibacter mysiganensis alone and the chemical agent kasugamycin / copper wettable powder as comparative controls.

The disease severity was evaluated by calculating the disease index, disease severity, and control value from the disease state of tomato.
Determination of disease incidence (morbidity index)
0: No symptom is observed 1: Symptom is less than 1/3 2: Symptom is less than 1/3 to less than 2/3 3: The symptom is 2/3 or more, but no death has occurred.
4: Withering

Σ (number of seedlings by disease severity x disease index)
Disease severity = ───────────────── × 100
Number of surveyed seedlings x 4

(Severity of untreated section)-(Severity of treated section)
Control value = ───────────────────── × 100
Disease severity in untreated areas

  From the results in Table 1, it can be seen that when treated with Erbinia carotobola subspicarotobola, it has almost the same control effect as compared with chemical agents.

Adjust the Erwinia carotovora subsp. Carotovora subsp. Carotovora CGE234M403 to a bacterial concentration of 2 × 10 ⁸ cfu / ml, then dilute the pathogen Clavibacter michiganensis with water 2 × What was adjusted to 10 ⁶ cfu / ml and 2 × 10 ⁷ cfu / ml was mixed with the above-mentioned Erwinia carotobola subsp. Carotobola bacteria to prepare two types of suspensions.

  Next, 1 ml of the above-mentioned two types of bacterial suspensions were inoculated into the side buds of the first true leaves with a syringe with the three to four leaf tomatoes (variety Momotaro) grown in the pot. Thereafter, the disease was investigated 4 weeks later.

  Next, Table 2 also shows the results of using the treatment group (non-treatment group) of the pathogenic fungus Clavibacter mysiganensis alone and the chemical agent kasugamycin / copper wettable powder as comparative controls.

  The method for calculating the disease index, disease severity, and control value was the same as in Example 1.

  From the results in Table 1, it can be seen that when treated with Erbinia carotobola subspicarotobola, it has almost the same control effect as compared with chemical agents.

The ratio of 300L / 10 are obtained by diluting Erwinia carotovora subsp. Carotovora CGE234M403 to 3 to 4 leaf tomatoes (variety Momotaro) grown in a pot to a bacterial concentration of 1 × 10 ⁸ cfu / ml The next day, the pathogen Clavibacter michiganensis was diluted to a bacterial concentration of 1 × 10 ⁶ cfu / ml or 1 × 10 ⁷ cfu / ml and sprayed at a rate of 300 L / 10 are.

Ten days later, Erwinia carotovora subsp. Carotovora CGE234M403 was diluted to a bacterial concentration of 5 × 10 ⁷ cfu / ml and sprayed at a rate of 300 L / 10 ares. michiganensis) was diluted to a bacterial concentration of 1 × 10 ⁶ cfu / ml or 1 × 10 ⁷ cfu / ml and sprayed at a rate of 300 L / 10 are, and then the disease was investigated 4 weeks later.

  Next, Table 3 also shows the results of using the treatment group (non-treatment group) of the pathogenic bacterium Clavibacter mysiganensis alone and the chemical agent kasugamycin / copper wettable powder as comparative controls.

  The method for calculating the disease index, disease severity, and control value was the same as in Example 1.

  From the results in Table 3, it can be seen that the treatment with erbinia carotobola subspicarotobola has a higher control effect than chemical agents.

Claims (7)

A control agent for controlling a solanaceous plant disease characterized by containing an avirulent Erwinia carotovora subsp. Carotovora bacterium as an active ingredient. The control agent according to claim 1, wherein the non-pathogenic Erwinia carotobola subsp. Carotobola bacterium is at least one selected from CGE6M14, CGE6M16, CGE10M2, CGE11M5, and CGE234M403. The control agent according to claim 1 or 2, wherein the solanaceous plant disease is a scab. A method for controlling a scab disease of a solanaceous plant, comprising bringing the control agent according to any one of claims 1 to 3 into contact with a solanaceous plant. The control agent according to any one of claims 1 to 3 is mixed with water to form a suspension, and the solanaceous plant is soaked in the suspension. Control method. The control agent according to any one of claims 1 to 3 is mixed with water to form a suspension, and the suspension is sprayed onto a solanaceous plant. Control method. The method according to any one of claims 4 to 6, wherein the solanaceous plant is tomato.