JP2002284615A - Thermophilic bacterium-containing pesticide for controlling rosellinia necatrix and controlling method of rosellinia necatrix - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel pesticide for effectively controlling Rosellinia necatrix, and to provide a method for controlling a white root rot using the pesticide. SOLUTION: The pesticide for Rosellinia necatrix is characterized by that it contains thermophilic bacteria. The method for controlling a white root rot uses the pesticide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control agent against white root rot (Rosellinia necatrix), which is a kind of ascomycetes, which contains a thermophilic bacterium and to which the control agent is applied. The present invention relates to a method for controlling crested wing disease, in particular, crested wilt disease.

[0002]

BACKGROUND ART White root rot is an important soil disease caused by white root rot (Rosellinia necatrix), which is a kind of ascomycetes, and has been used for many years in fruit trees such as apples, pears, grapes, and plums as well as timbers. It is known as a multicriminal fungus that infects plants of more than 170 species of 63 genera including plants such as soybean and narcissus. As with other soil diseases, the diseased plants suffer from poor growth, weakness, withering, yellowing, root rot, and early leaf fall and die. A specific white-grey-brown fan-shaped white hypha membrane, a mycelium bundle, a conidiophore bundle, and the like are observed at the base of the diseased plant. Perennial crops are seriously damaged by this disease, survive in the soil and on the diseased roots as pseudonuclei, and have a strong viability and are considered to be soil diseases that are difficult to control. In addition, regarding the white root rot, “Encyclopedia of Plant Soil Diseases”, written by Tsuneo Watanabe, Asakura Shoten, pages 211 to 217 (1
998).

At present, chlorpicrin, isobrothion, thiophanate methyl, benomyl, and the like are known as pesticides using chemically synthesized substances for white root rot, but none of them are surely effective. Is the current situation. Furthermore, consumers' awareness of environmental conservation and food safety are increasing, and there is an urgent need to switch from cultivation of pesticide-picked crops that use large amounts of synthetic chemicals to cultivation of organic and non-pesticide-based crops. Has become.

[0004] Therefore, a control method using a microorganism instead of a chemically synthesized fungicide has been proposed.
For example, a method using actinomycetes has been proposed as a method for controlling mulberry white root rot (“Elucidation of dynamics of rhizosphere environment and development of control technology” Agriculture and Forestry Technology Council secretariat research result No. 274, 19).
1992, pp. 49-51). Further, JP-A-6-256
No. 125 discloses a white root rot control agent and a white root rot control method using Trichoderma spp. Japanese Patent Application Laid-Open No. 10-36211 discloses a white root rot control agent and a white root rot control method characterized by containing a fungus belonging to the genus Gliocladium.

[0005]

DISCLOSURE OF THE INVENTION The present invention relates to a white root rot fungus (Rosellinia necatri) for effectively controlling white root rot.
It is an object of the present invention to provide a new control agent for x) and a method for controlling white root rot using the control agent.

[0006]

That is, the present invention is characterized by containing a thermophilic bacterium;
inia necatrix) and a method for controlling white root rot, comprising applying the agent for controlling white root rot of the present invention.

Here, the thermophilic bacterium is generally 55
A bacterium that grows in a high-temperature environment of ℃ or higher, which means “moderate thermophile” that grows at temperatures up to 75 ° C, a “highly thermophilic bacterium” that grows at temperatures higher than that, and grows at 90 ° C or higher "Hyperthermophilic bacteria".

[0008] The thermophilic bacteria contained in the control agent of the present invention have a significant growth inhibitory effect against white root rot, which is a pathogen of soil disease, by a paper disc test as described later in this specification. The strains shown can be appropriately selected and used. Further, the controlling agent of the present invention can contain one or more thermophilic bacteria. The genus of the thermophilic bacterium that can be used in the present invention is not particularly limited as long as such conditions are satisfied. Examples thereof include bacteria belonging to the genus Bacillus, in particular, Bacillus stearothermophilus, Bacil
lus brevis and thermophilic actinomycetes (Thermophilic actinomy
cetes) as well as thermophilic bacteria belonging to closely related species of these species.

For example, as a preferred example of the thermophilic bacterium contained in the controlling agent of the present invention, Bacillus stear which is a thermophilic bacterium is used.
othermophilus CH-4, a thermophilic bacterium CH-1 and a thermophilic bacterium CH-3, which are closely related species of Bacillus brevis, and Bacillus
Thermophilic actinomycetes MH-1 (Thermophil with some characteristics of the genus
ic actinomycetes MH-1). Such a thermophilic bacterium group expressed a large number of enzymes having a high ability to degrade chitin / chitosan and the like contained in a large amount of shrimp and / or crab residues. The bacteriological properties of these thermophilic bacteria are shown in Table 1 below.

[0010]

[Table 1]

[0011] Such thermophilic bacteria are collected and separated from a mixed fermentation product of the soil in the mountains of Sankobo, Kitsuki City, Oita Prefecture and the marine shrimp in Beppu Bay. Under the Budapest Treaty on the International Recognition of the Deposit of Microorganisms, "Thermophilic Inoculum Miroku" (Thermophilic inocu
lum MIROKU) was deposited on May 1, 2000, with the international depository institution ATCC (USA), and has been assigned a deposit number (international deposit number) PTA-1773.

[0012] Thermophilic bacteria can be cultured by any method known to those skilled in the art. For example, an appropriate amount of thermophilic bacteria can be added to an appropriate solid medium, for example, an organic material, and solid culture can be performed under aerobic conditions, for example, at 50 to 90 ° C. Examples of the organic material include marine residues, insects, animals, coffee scum, straw, rice hulls, rice straw, tea scum, edible waste oil, bean seed coats such as soybeans, red beans, and peanuts, and the like.
Various organic substances such as fallen leaves, bark, livestock manure, microorganisms that have eaten these seafood residues, and the like, and mixtures of appropriate combinations thereof can be mentioned.

Although the state and form of the organic material to be used are arbitrary, for example, it can be used in a raw state containing water of about several tens% of the total weight. The culture is performed by adding a predetermined ratio of the thermophilic inoculant Miroku to the organic material, and heating the thermophilic inoculum Miroku by self-fermentation heat or an appropriate heating means such as a heater under aerobic conditions such as stirring under an air atmosphere. Preferably, the heat treatment may be performed at 50 to 90 ° C. When far-infrared irradiation is used, there is an advantage that the temperature can be raised in a shorter time.

In particular, when culturing the thermophilic inoculant Miroku, it is preferable to use a mixture of marine residues and coffee grounds as the organic material. In this case, the mixing ratio of the marine residue and the coffee residue is desirably about 7: 3 by weight.

When at least a marine residue is used as an organic material, the activity of the thermophilic inoculant Miroku becomes higher due to the high-quality antioxidant components, mineral components, and a large amount of chitin components contained therein. . For this reason, there is an advantage that fermentation by culturing is continued for a long time and antioxidant functional components such as a thermostable enzyme derived from the thermophilic inoculant Miroku bacterium and chaperonin can be mass-produced. Such marine residues include:
For example, shrimp, crabs, inedible parts except edible parts from marine products such as fish, or shrimp not suitable for food,
Small crab, small fish and the like can be mentioned.

Since the water content of the mixture decreases as the cultivation progresses, the cultivation is continued for several hours to several tens of hours until the water content becomes about 20% by weight or less, so that the thermophilic inoculum Miroku can be converted to an organic material. Can be fixed. At this time, a distillate is generated, which can be used in liquid culture.

Further, the thermophilic bacterium of the present invention can be cultured in a liquid by an appropriate method. For example, a thermophilic inoculum miloc (or a thermophilic inoculum miloc immobilized on an organic material by culturing using an organic material) is mixed with water, the above-mentioned distillate,
Or a mixture thereof, under aerobic conditions, for example,
30-70 by heating with self-fermentation heat or heater
It can be cultured at ℃. To 100 L of water, a thermophilic inoculum can be added at an appropriate ratio, for example, about 1 L.

In the liquid culture as described above, the thermophilic inoculant Miroku is actively multiplied. Therefore, the liquid culture containing a large amount of an antioxidant functional component such as a thermostable enzyme derived from the thermophilic inoculum Miroku and a chaperonin. There is an advantage that a product can be manufactured. Here, when the distillate was used for liquid culture, the distillate contained an antioxidant functional component derived from the thermophilic inoculum Miroku, and the powdery thermophilic inoculum Miroku was used as a powder. Since it is easy to dissolve or adapt, there is an advantage that culture can be performed more efficiently.

The controlling agent of the present invention containing a thermophilic bacterium comprises:
Any form and property such as dry powder, granule, paste and liquid can be taken. For example, after culturing a thermophilic bacterium, one kind of thermophilic bacterium separated by an appropriate method such as centrifugation or a thermophilic bacterium itself comprising a mixture of several kinds thereof, or culturing the thermophilic bacterium by an appropriate method (Solid or liquid, etc.) per se, or a cultured product obtained by appropriately subjecting the culture, if necessary, to pulverization, concentration and / or drying.

Further, the thermophilic bacteria themselves, a culture or a culture-treated product may be supported on a suitable carrier, or may be used as a controlling agent of the present invention in the form of a fixed carrier (eg, granular). You can also. As the carrier, any of organic and inorganic substances can be used, and those containing both organic and inorganic substances may be used. Specifically, for example,
Attapulgite, montmorillonite, zeolite, Akadama soil, Kanuma soil, Kuroboku soil, Akadama soil, calcined Akadama soil, vermiculite, perlite, minerals such as fossil shells, or
Organic substances such as peat moss, charcoal such as charcoal, pulp, straw, bagasse, oil cake, fish cake, bone meal, blood meal, crab chunks and various composts, and the above-mentioned organic materials and mixtures thereof. Among them, porous carriers such as attapulgite, montmorillonite, zeolite, peat moss, and charcoal are preferred from the viewpoints of water retention ability, fertilization retention ability, or convenience in use.

The control agent of the present invention may further contain any auxiliary agent or additive known in the art. Examples of such auxiliaries or additives include, for example, organic acids such as acetic acid, propionic acid, lactic acid and butyric acid, molasses, wood vinegar, starch, lactose, and nutrient sources of thermophilic bacteria such as phosphoric acid. Alternatively, a substance that can be a substrate can be used. In the control agent of the present invention, the mixing ratio of the thermophilic bacterium and the carrier and / or auxiliary agent or additive,
Those skilled in the art can appropriately select the form and properties of the controlling agent, the purpose, frequency and method of use, and the type of each component.

The present invention further relates to a method for controlling white root rot, which comprises applying the agent for controlling white rot of the present invention.

In carrying out the method of the present invention, an organic acid composition, phosphoric acid and a carrier can be applied as other components in addition to the controlling agent. The organic acid composition functions as a nutrient of thermophilic bacteria contained in the control agent and / or as a bactericide against white rot fungus, and the carrier is capable of fixing the thermophilic bacteria thereon and stably growing in soil. It is thought to provide such an environment. However, there are unknown and uncertain factors regarding the functions of such an organic acid composition and a carrier, and the scope of the present invention is not limited by the functions performed by these elements.

The organic acid composition is a composition containing an organic acid as a main component and capable of taking any form. For example, a liquid containing at least one organic acid such as acetic acid, propionic acid, lactic acid and butyric acid For example, an organic acid aqueous solution or a wood vinegar solution can be used. Here, the wood vinegar generally refers to a water-soluble solution obtained when carbonizing wood.
The composition and quality vary depending on each condition such as wood (tree species) used as a raw material, the structure and type of the kettle, the structure of the sampling storage device, the sampling temperature (smoke outlet temperature), etc., but acetic acid, propionic acid, lactic acid and Contains organic acids such as butyric acid as main components, and various organic phenols, carbonyl compounds such as aldehydes, alcohols, bases, and other neutral components. (Maruzen: “Wood Industry Handbook” edited by Forestry Research Institute, 1972; published by S 森 morisha: “Wood vinegar ・
Charcoal and Organic Agriculture, by Toshiro Saegusa, August 2000). In addition, examples of the carrier include a porous carrier such as charcoal described above.

Further, in addition to the control agent and the like of the present invention, components such as a soil conditioner known in the art and inorganic fertilizers such as organic and / or phosphoric acid can be arbitrarily applied.

In the method for controlling white root rot of the present invention, there are no particular restrictions on the plants to which the control agent is applied, and any plant that can suffer from white root rot can be the subject of the method of the present invention. For example, cedar, sawara, hemlock, larch,
Maple, camphor, poplar, zelkova, oak, oak, beech, goby, cherry, kouzo, mitsumata, mulberry, cha, citrus, apple, oyster, pear, peach, plum, plum, apricot, cherry, loquat, fig, spruce, Plants such as Satsuki, Azalea, Gardenia, Boxwood, Masaki, Ginkgo, Ulsi, Hakuunboku, Chestnut, Kunugi and the like can be mentioned.

The types and amounts of thermophilic bacteria and other components contained in the controlling agent used in the controlling method of the present invention;
And, the type, amount and proportion of the pesticide, the organic acid composition, the carrier, and the like, the method of applying the pesticide, the time of application, the type of target plant, the cultivation state of the plant, the type of soil, and Those skilled in the art can appropriately select various conditions such as the degree of progress of the disease state. Furthermore, there is no particular limitation on the method of applying the controlling agent, the timing, etc., and the types and amounts of the thermophilic bacteria and other components contained in the controlling agent, the controlling agent, the organic acid composition, the types and amounts of the carrier, Those skilled in the art can comprehensively judge and select based on various conditions such as the type of the target plant, the cultivation status of the plant, the type of land, the time of application, and the degree of progress of the disease state.

For example, the control agent of the present invention can be applied in an amount of about 200 to 300 L per 10 ares. On the other hand, in the case of an aqueous solution containing at least one kind of organic acid such as acetic acid, propionic acid, lactic acid and / or butyric acid, the organic composition is about 1 to 10 L per 10 ares. It can be applied in quantity.
Further, for example, a carrier such as charcoal can be applied in an amount of, for example, about 100 to 200 L per 10 ares. It is also possible to apply several types of controlling agents of the present invention containing different thermophilic bacteria in appropriate combinations in the method of the present invention.

As a specific application method in the controlling method of the present invention, for example, a method of directly applying the controlling agent of the present invention to the roots of the diseased plant, immersing the roots in the controlling agent, a method of surrounding the affected roots, Method of irrigation with a pesticide and other optional ingredients into the soil of the plant, removing the soil around the roots of the diseased plant, and injecting the pesticide and other optional ingredients into the holes formed around the roots, etc. There is. It is not necessary to apply the control agent and other optional components at the same time, and they can be applied at appropriate intervals. Further, the pesticide and other optional components are not mixed and applied in a homogeneous state. For example, the pesticide and other optional components can be applied alternately and in layers.

Further, the controlling method of the present invention includes applying the controlling agent of the present invention as a preventive treatment before the plant body becomes infected with white root rot. The control method of the present invention also includes treating soil in advance with the control agent or the like of the present invention before cultivating the target plant.

These various methods can be carried out in an appropriate combination, or can be carried out a plurality of times at appropriate intervals depending on the condition of the diseased plant.

[0032]

The present invention will be described in more detail with reference to the following examples.
The present invention is not limited to such an embodiment.

[0033]

Embodiment 1Characteristics of thermophilic bacteria  Thermophilic inoculum MIROKU
As described below, a thermophilic bacterium which is a controlling agent of the present invention
Granules and thermophilic stock solutions were prepared.

[0034]Thermophilic bacteria (antioxidant thermophilic bacteria) granules  Under conditions in which the thermophilic inoculant Miroku was immobilized with coffee grounds,
D, shrimp and small fish as medium for about 12 hours, heater
Fermented at 70-90 ° C without using heating means such as
And then dried to a moisture content of about 20% to
Bacterial granules were prepared.

[0035]Undiluted solution of thermophilic bacteria (antioxidant thermophilic bacteria)  Pulverize the thermophilic granule and dilute it 100 times with water
Then, evacuate for more than 4 hours at about 40-60 ° C.
A light thermophilic stock solution was prepared.

These were cultured as samples to confirm the general characteristics of the thermophilic bacteria contained in the control agent of the present invention.
In addition, a standard agar medium was used for each culture. The number of viable bacteria was measured by a method well known to those skilled in the art. Cell count

[0037]

[Table 2]

[0038]

[Table 3]

[0039]Antioxidant component  Prevent degradation of the thermophilic bacterial granules used in Example 1
The amount of antioxidant components contained was analyzed.

[0040]

[Table 4]

Note 1. See JBC, 244, 6049 (1969). Note 2. Measured after derivatization with hydrazine. Note 3. Measured with 4-aminoantipyrine-hydrogen peroxide system. 25 degrees
C, pH 7.0, activity to decompose 1 μm of hydrogen peroxide per minute was defined as 1 unit.

[0042]

Embodiment 2Organic acid availability of thermophilic bacteria Method  Stock solution of thermophilic bacterium as a controlling agent of the present invention prepared in Example 1
Organic acid concentration in organic acid-containing solutions with or without the addition of
Analysis of changes over time with high-performance liquid chromatography
did. First, acetic acid, propionic acid, butyric acid, lactic acid was 5 mM each,
After adjusting to 10mM, 20mM aqueous solution, make a calibration curve,
After adding 2 ml of the thermophilic bacterium stock solution to 400 ml of each aqueous solution,
The change in the concentration of the organic acid was measured up to 72 hours. Got
The results are shown in Table 5 below.

[0043]

[Table 5]

The above results indicate that wood vinegar containing these organic acids is useful as a nutrient source for thermophilic bacteria.

[0045]

Embodiment 3For trees affected by crested wilt disease in the field
Test using all the pesticides of the present invention  (Implementation location: Onoda-cho, Funabashi-shi, Chiba) The controlling agent of the present invention
However, what kind of shadows do trees actually have
Suffered white root rot, with the aim of investigating
For Kosui (32 to 3 years old)
Field tests were performed.

[0046]1. Investigation of affected trees and administration of pesticides
(November 30, 1999)  Approximately 1 meter from the ground surface to the root of a tree affected by the fungus
When digging and confirming the affected area with the naked eye,
Is discolored to blackish brown and necrotic.
Almost no fine roots could be observed. Close to the root
Still had mild symptoms and some fine roots.

Subsequently, the diseased root was cut, and the remaining root part (treated root) was washed with the liquid thermophilic bacterium stock solution prepared in Example 1, which is the controlling agent of the present invention. 90 liters of the thermophilic bacterium granules prepared in 1 and processed in powder form and 15 liters of a liquid solution of the thermophilic bacterium stock solution immersed in the diseased roots for 24 hours were mixed and applied around the treated roots.

Further, 130 liters of a 10-fold dilution of a liquid thermophilic bacterium stock solution, phosphoric acid (yorin) was applied to the entire excavated hole.
40 kg, 200 l of charcoal charcoal, and 140 l of wood vinegar were alternately applied in layers, and finally, 1 cubic meter of compost was applied thereon and covered with soil.

[0049]2. Field survey (August 22, 2000)  When the top of the root was partially excavated and the rooting state was confirmed, the diameter
Several roots of several millimeters were confirmed. Also, the upper part of the processing root
Rooting has been confirmed, so this new root is
Trees can recover if they have enough momentum to fight
There was sex.

In general, when a surgical procedure such as excising the affected root is simply performed, recurrence is not possible if the soil is still contaminated with white root rot fungi as before. Since the nature is large, the progress was further observed, and after defoliation, the root portion was dug to confirm the rooting situation.
In addition, a live tree was stabbed under the tree of each pear in order to visually check whether or not infection of the fungus was observed at the next survey.
Normally, if the propagation of the fungus is progressing, a group of the fungus is observed on the living tree. We decided to observe this in the next excavation survey.

[0051]3. Drilling survey (November 15, 2000)  Fine root development is clearly progressing compared to the state one year ago
Was visually observed. Seen earlier in the soil
Many small animals such as earthworms were observed. Further
Then, the raw tree that had been stabbed in the soil in advance was taken out and observed.
As a result, no live trees infected with the white root rot fungus group were found.

Through the above-mentioned field investigations, it was observed that the control agent of the present invention ameliorated the symptoms of trees infected with white root rot. This result shows that, in addition to the growth inhibitory effect against white root rot by the control agent of the present invention, furthermore, the combination with each component such as phosphoric acid, granular charcoal, and wood vinegar is excellent against white root rot. It shows that the epidemic prevention effect was obtained. in addition,
The fact that a large number of small animals were observed indicates that each component used this time exerted a high-quality fertilizer effect, creating a fertile soil environment and reducing soil contamination by pesticides, especially antibacterial agents. It was presumed to be one of the causes.

[0053]

Embodiment 4Inhibition of growth of white root rot on discs
Effect test  The thermophilic bacterium stock solution (thermophilic bacterium material) prepared in Example 1
How does it affect the growth of the scab
Purposes to clarify from microbiological, physiological and biochemical viewpoints
The following test was conducted.

A potato dextrose inoculated with a white root rot fungus (transferred from Prof. Umemoto, Chiba Prefectural Agricultural Exp. Stn.) Or a paper disk (ADVANTEC, for antibiotics assay, Diameter 8mm,
Thick) was placed and cultured at 25 ° C. to observe the effect. As a control, a thermophilic bacterium contained in a thermophilic bacterium stock solution was previously sterilized using a filter (MILLIPORE MiR).
(Llex pore size: 0.22 μm) was placed on a bed, and observed in the same manner.

After one week and one month, the shape of the bacterial colonies was observed. As shown in FIG. 1, no white rot fungus was observed in the peripheral area of the thermophilic bacteria-impregnated disk. The effect was shown. Furthermore, such a growth inhibitory effect against white rot fungi was observed even after one month. On the other hand, when the thermophilic bacterium was filtered to remove the cells, such a growth inhibitory effect was not recognized.

[0056]

According to the present invention, there is provided an agent for controlling a white rot fungus (Rosellinia necatrix), which comprises the thermophilic bacterium of the present invention, and has a remarkable growth inhibitory effect against a white rot fungus in a disk test. Was confirmed. Furthermore, in an actual field test using the pesticidal agent of the present invention on a tree infected with white root rot, it was confirmed that the control method of the present invention exhibited an excellent epidemic control effect on white root rot. .

[Brief description of the drawings]

FIG. 1 shows the results of a growth inhibitory effect test of the thermophilic bacterium of the present invention on a white rot fungus on a disk.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Hirokuni Miyamoto 9-11-1 Green Park 1207 Miyamoto, Funabashi-shi, Chiba Japan Environmental Science Corporation (72) Inventor Hirofumi Shinoyama 669 Maegasaki, Nagareyama-shi, Chiba Prefecture -2 Rene Minamikashiwa 811 (72) Inventor Eikichi Takahashi 617-2 Matsudo Nitta, Matsudo-shi, Chiba F-term (reference) 4H011 AA01 BA01 BB21 BC06 BC18 BC22 DA02 DA15 DD03

Claims (9)

[Claims] 1. An agent for controlling white root rot, comprising a thermophilic bacterium. 2. The control agent according to claim 1, wherein the thermophilic bacterium is a thermophilic bacterium group containing several kinds of thermophilic bacteria. 3. The thermophilic bacterium is Bacillus stearothermophi.
lus, Bacillus brevis and thermophilic actinomycetes (Thermophil
3. The control agent according to claim 1, wherein the control agent is one or several kinds selected from the group consisting of thermophilic bacteria belonging to closely related species of these species. 4. The controlling agent according to claim 3, wherein the thermophilic bacterium is a thermophilic inoculant Miroku. 5. The control agent according to claim 1, which comprises a culture or a processed product of thermophilic bacteria. 6. A method for controlling white root rot, comprising applying the control agent according to any one of claims 1 to 4. 7. The control method according to claim 6, further comprising applying an organic acid composition, phosphoric acid and a carrier. 8. The control method according to claim 7, wherein the organic acid composition is wood vinegar and the carrier is charcoal. 9. The control method according to claim 6, wherein a pear affected by white root rot is targeted.