JP2003192515A - Plant disease controlling agent and controlling method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plant disease controlling agent capable of being used as a microbial pesticide against bacterial diseases broken out during seedling culture of Gramineae (rice family) plants. <P>SOLUTION: This plant disease controlling agent contains one or more kinds of fungi and one or more kinds of bacteria as active ingredients, wherein the fungi belong to any of Trichoderma, Fusarium, Penicillium, Saccharomyces, and Gliocladium genera having controlling activity on fungous or bacterial diseases broken out during the seedling culture of the rice family plants, and the bacteria belong to any of Pseudomonas, Bacillus, and Enterobacter genera having controlling activity on the bacterial diseases broken out during the seedling culture of the rice family plants. A method for controlling the plant diseases comprises using the controlling agent. Rice seeds treated with the plant disease controlling agent and a rice seedling culture soil treated with the same are provided in the specification, respectively. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a control agent and a control method using microorganisms for infectious diseases of seeds of grasses. More specifically, the present invention relates to a plant disease control agent and a method for controlling a plant disease containing, as an active ingredient, a filamentous fungus and a bacterium having an ability to control filamentous fungal and bacterial diseases that occur during the raising of rice plants.

[0002]

2. Description of the Related Art Diseases that occur during seedling raising of gramineous plants include rice scab seedling disease, sesame leaf blight, caused by filamentous fungi.
Examples include blast disease and bacterial diseases such as rice bacterial blight, bacterial seedling blight, and brown stripe disease caused by bacteria. It is said that seed disinfectants, soil admixtures, soil irrigation agents, foliage sprays after greening, etc. are effective for controlling these diseases, and chemical agents are used alone or in combination. A highly effective EBI agent for diseases caused by filamentous fungi,
Oxolinic acid agents and cupric hydroxide agents are used for bacteria. However, in some cases, stable effects cannot be expected due to the emergence of resistant bacteria with reduced sensitivity to these drugs. In addition, chemical pesticides require proper treatment of used waste liquid, which is a burden on workers.

Under these circumstances, in recent years, research on biological control using microorganisms, which is assumed to have a lower environmental load from chemical pesticides, has been advanced, and some of them have been put to practical use. Also in the control of the rice seed infectious disease described above, the non-pathogenic Pseudomonas gourmet effective against rice bacterial wilt disease in JP-A-4-295407 discloses pathogenicity in JP-A-6-87716. It has been disclosed that the deleted Erwinia cultivator is effective in controlling bacterial seedling bacterial disease. Further, Pseudomonas spp. Which are effective for rice bacterial blight, seedling bacterial blight, and rice stupid bacterial disease are disclosed in Japanese Patent Laid-Open No. 9-124427, and Pseudomonas sp. Aureofaciens "1999 results of biological pesticide communication test" (Japan Plant Protection Association, 2000 1
Month). On the other hand, microorganisms belonging to the genus Trichoderma effective for filamentous fungal disease rice scab seedling disease, blast disease, etc. are disclosed in JP-A-11-225745, and also Trichoderma trichoderma, which is effective for bacterial pathogen bacterial bacterial blight. Microorganisms belonging to the genus are disclosed in JP-A No. 11-253151. However, as biocontrol using microorganisms generally materializes, a stable effect comparable to chemical pesticides with biological pesticides using these microorganisms, and a control agent with a low environmental impact that is effective with a low dose However, it was difficult for each of them to satisfy these requirements in a stable manner.

[0004]

In view of the above-mentioned present situation, the present inventor, in controlling rice seed infectious diseases,
As a result of research aiming to establish stable control technology that is safer to the environment and is not likely to develop resistant bacteria, as a result of the research, it is possible to control filamentous fungal and bacterial diseases that occur during seedling raising Control of bacterial diseases and filamentous fungal diseases by simultaneously applying, as an active ingredient, a specific filamentous fungus having the ability and a specific bacterial germ having the ability to control bacterial pathogens that occur during the raising of rice plants The present inventors have found that the concentration of the active ingredient used can be significantly reduced while stabilizing the effect.

[0005]

The present invention provides Fusarium, a genus of Trichoderma having the ability to control filamentous fungal and bacterial diseases that occur during seedling raising of grasses.
(Fusarium), Penicillium, Saccaromyces, or Gliocladium
Ocladium) at least one filamentous fungus belonging to any of the genus, and Pseudomonas genus (Pseudomonas) genus, Bacillus genus or Enterobacter (Enterobac
The present invention relates to a plant disease control agent containing as an active ingredient at least one bacterium belonging to any one of the genus ter). It also relates to a method for controlling plant diseases using these control agents. Furthermore, the present invention relates to rice seeds and rice seedling culture soil treated with these plant disease controlling agents. By simultaneously applying the above-mentioned filamentous fungus and bacteria, a stable and high effect can be obtained against rice seed infectious bacterial disease and filamentous fungal disease.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION A filamentous fungus having a controlling ability against a filamentous fungal or bacterial disease occurring during seedling raising of a Gramineae plant used in the present invention is Trichoderma.
Genus, Fusarium, Penicilli
um), Saccharomyces, or Gliocladium is a filamentous fungus that belongs to any of the genus Gliocladium, as a microorganism belonging to the genus Trichoderma, preferably Trichoderma harzianum (Tri
choderma harzianum), Trichoderma aureobilide
(Trichoderma aureoviride), Trichoderma atroviride, Trichoderma atrooride
(Trichoderma viride), Trichoderma vining
choderma konigii), Trichoderma pseudokonigii, Trichoderma lomgibrachiatum, and Trichoderma hamatum. Further, as a microorganism belonging to the genus Fusarium, preferably Fusarium avw
naceum), Fusarium oxyspram
orum), Fusarium monilif
orme), Fusarium sporo tricoide
trichoide), Fusarium clumor
um). Further, as the microorganism belonging to the genus Penicillium, preferably, Penicillium simprisisimum can be mentioned. Further, as a microorganism belonging to the genus Saccharomyces, preferably Saccharomyces cerevisiae
(Saccharomyces cerevisiae). As a microorganism belonging to the genus Gliocladium, preferably gliocladium v
irens), Gliocladi vermoeseni (Gliocladi
um vermoeseni), Gliocladium aureum (Gli
ocladium aureum).

Bacteria having the ability to control filamentous fungal or bacterial pathogenic bacteria occurring during seedling raising of grasses used in the present invention include Pseudomonas spp., Bacillus spp. Or Enterobacte spp.
r), a bacterium belonging to the genus Pseudomona
Examples of the microorganism belonging to the genus s) are preferably microorganisms belonging to Pseudomonas aureofaciens and include Pseudomonas aureofaciens B-5 strain. This bacterium was transferred to Pseudomonas aureofaciens (Pse
udomonas aureofaciens) B-5 strain, FERM BP-6067.

The microorganism belonging to the genus Bacillus is preferably Bacillus polymixer (Bacillus).
Polymyxa), of which a particularly preferred strain is Bacillus polymyxa B-3.
Six strains are exemplified. This bacterium was transferred to Bacillus polymyxa at the Patent Biological Depositary Center, National Institute of Advanced Industrial Science and Technology.
(Bacillus polymyxa) B-36 strain, deposited as FERM BP-6068.

The microorganism belonging to the genus Enterobacter is preferably Enterobacter.
A microorganism belonging to the cloaca (Enterobacter cloacae),
Among them, particularly preferable strains are Enterobacter
An example is the Enterobacter cloacae B-51 strain. This bacterium can enter Enterobacter cloaca (Enter
bacterium cloacae) B-51 strain, deposited as FERM BP-6067. These microorganisms may be those grown by known means such as culture with materials such as bran, static culture with solid medium, liquid culture, etc., and are particularly limited to the type of medium, culture conditions, etc. Not a thing.

In the present invention, the above-mentioned filamentous fungi and bacteria which are not pathogenic to rice are used in combination. The amount of the above-mentioned filamentous fungi and bacteria to be used is appropriately selected depending on the dosage form of the preparation, the application method, the application crop and place, the type of disease to be applied, etc., but the spore concentration of the filamentous fungus is 1 × 10 ² ~ It is desirable to use in the range of about 10 ⁹ / ml, preferably 1 × 10 ⁴ to 10 ⁸ / ml. The concentration of the bacterium is 1 × 10 ² to 10 ¹¹ cfu / ml.
It is preferable to use in the range of about 1 × 10 ⁵ to 10 ⁹ cfu / ml.

For the plant disease controlling agent of the present invention, the culture solution or suspension of these microorganisms may be used as it is, or the microorganisms may be mixed with, for example, a solid or liquid carrier, and if necessary, added in a usual manner. Preparations are made by adding agents and other auxiliaries. In this case, a preparation in which filamentous fungi and bacteria are mixed may be prepared, or a preparation containing filamentous fungi and a preparation containing bacteria may be separately prepared and mixed in a desired ratio at the time of application.

The application of the plant disease controlling agent of the present invention can be carried out by dressing, smearing or spraying on the seeds of grasses. Further, seeds of grasses are dipped in a suspension of these microorganisms, or suspensions or fungi containing these microorganisms are irrigated and mixed in the soil, or sprayed on the grasses themselves in the field. It can be applied by foliage treatment.

Further, the plant disease controlling agent of the present invention does not prevent mixing with other plant disease controlling agents. For example, it may be mixed with an insecticide, a nematicide, an acaricide, a herbicide, a plant growth promoter, a synergist or the like, or may be used together without being mixed.

The plant disease controlling agent of the present invention is effective against a disease occurring in a grass family plant, and as effective diseases, a rice seedling bacterial blight (Burkholderia plantarii) and a rice bacterial blight (Burkholderia glumae) are used. ), Rice stripe disease (A
cidodovorax avenae), rice gown browning disease (Erwinia herb)
oicola), brown leaf sheath of rice (Pseudomonas fuscovagina)
e), and rice leaf blight (Xanthomonas campestris p
v. oryzae) and rice blast (Pyricularia oryza)
e), rice scab seedling disease (Gibberella fujikuroi), rice sesame leaf blight and the like (Cochliobolus miyabeanus) can be exemplified, but the plant diseases are not limited to these. Hereinafter, the present invention will be specifically described with reference to formulation examples and examples, but the present invention is not limited to these examples.

[0015]

[Formulation Example 1] Pseudomonas aureofaciens B5 wettable powder
The prepared Pseudomonas aureofaciens B5 was cultured in PPG medium with shaking at 30 ° C. for 24 hours, and centrifuged to collect the cells. This was resuspended in a liquid to which an appropriate protective agent was added, and then freeze-dried. The obtained solid was crushed, and a mineral carrier was added to and uniformly mixed to obtain a wettable powder containing 5% of dried cell bodies, 70% of carrier and 25% of protective agent.

[0016]

[Formulation Example 2] Preparation of suspension of Trichoderma harzianum Trichoderma harzianum was cultured in PDA medium at 25 ° C for 2 weeks,
Spores were suspended in distilled water. A mineral substance carrier was added to this and mixed uniformly to obtain a suspension containing 3% by weight of spores, 20% of carrier and 77% of water. In application, the above-mentioned wettable powder and suspension may be used in combination.

[0017]

[Example 1: Rice seedling bacterial bacterial control control effect test] Rice seeds (variety: Nihonbare) inoculated with the rice seedling bacterial bacterial killing agent (Burkholderia plantarii) at the flowering stage were prepared. The inoculated paddy was mixed well with healthy paddy so that the weight of the paddy was 5%, and the seeds were subjected to a control effect test. 15g of this paddy is diluted with the above-mentioned wettable powder and suspending agent to a predetermined concentration, and then mixed individually and subjected to a soaking treatment for 24 hours (bath ratio 1: 1), soaking at 15 ° C for 4 days, 32 ° C for 24 hours. After the germination, the seedlings were sowed on a commercial seedling cultivation medium, germinated at 32 ° C. for 2 days, and thereafter raised in a glass greenhouse. Twenty-one days after sowing, the total number of seedlings, the number of dead seedlings, the number of dead and partially dead seedlings in each treatment group were measured, and the control value was calculated from the disease severity. The results are shown in Table 1. Pseudomonas a
Even at a dilute concentration at which the control effect against bacterial seedling wilt disease in rice was reduced by treatment with ureofaciens alone, the control effect was improved by mixing the two, and a synergistic effect was observed.

[0018]

[Table 1]

[0019]

EFFECTS OF THE INVENTION The microbial control agent and control method of the present invention show an excellent synergistic effect and can significantly reduce the concentration used, leading to further resource saving, labor saving, and environmental conservation promotion. Is. For example, according to Table 1 of Example 1, the concentration of Pseudomonas aureofaciens B5 can be reduced to 1/100.

Claims (9)

[Claims] 1. Trichoderma having the ability to control filamentous fungal and bacterial diseases that occur during seedling raising of grasses.
(Trichoderma) genus, Fusarium genus, Penicillium genus, Saccharomyce
s), or at least one filamentous fungus belonging to any of the genus Gliocladium (Gliocladium), and pseudomonas (Pseudomonas) genus having an antagonistic action against bacterial pathogens occurring during the seedling raising of grasses, Bacillus ( Bacillus)
A plant disease control agent, comprising at least one bacterium belonging to either the genus or the genus Enterobacter as an active ingredient. 2. A bacterium belonging to the genus Pseudomonas is Pseudomonas aureofaciens.
As aureofaciens) B5 (FERM BP-6067). The plant disease controlling agent according to claim 1. 3. A bacterium belonging to the genus Bacillus is Bacillus polymyxa B36 (FERM BP-6068).
The plant disease control agent according to claim 1. 4. The bacterium belonging to the genus Enterobacter is Enterobacter cloaca.
cae) B51 (FERM BP-6069), The plant disease controlling agent according to claim 1. 5. A method for controlling plant diseases, which comprises subjecting plants to foliar treatment with the plant disease controlling agent according to any one of claims 1 to 4. 6. A method for controlling plant diseases, which comprises dipping, spraying, coating or dressing the plant disease controlling agent according to claim 1 on plant seeds or plant roots. 7. A method for controlling plant diseases, which comprises irrigating or admixing the plant disease controlling agent according to any one of claims 1 to 4 into soil. 8. A disease-controlling rice seed obtained by treating with the plant disease-controlling agent according to any one of claims 1 to 4. 9. A disease control rice seedling culture soil, which is treated with the plant disease control agent according to any one of claims 1 to 4.