JPH03219883A - Weed-controlling agent containing microorganism of genus drechslera or its metabolic product and method for controlling weed therewith - Google Patents

Abstract

PURPOSE:To obtain a herbicide harmless to human body and having improved controlling effect on cockspur-grass by using a specific microorganism of genus Drechslera as an active component. CONSTITUTION:Pathogenic microorganisms separated in pure state from the diseased part of a spontaneously infected cockspur-grass are cultured to obtain a microbial strain of genus Drechslera free from pathogenicity to useful plants such as rice and wheat and exhibiting pathogenicity to plants of genus Echinochloa [e.g. Drechslera monoceras MH-0015 (FERM P-10785)]. The strain is cultured in a nutrient medium and the obtained spores are suspended in an aqueous solution of a nonionic surfactant such as Triton X-100 or Tween 80 to obtain a weed-controlling agent. The controlling agent exhibits herbicidal effect exclusively against cockspur-grass when scattered on a paddy field at a time before or after the transplantation of rice plant.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention is directed to the cultivation of useful plants such as weeds, especially rice, which is an important grain of the Poaceae family, and wheatgrass, etc.
The present invention relates to a weed control agent containing viable cells of a plant pathogenic microorganism of the genus Drechlera or its metabolites that are effective in controlling Echinochloa (scientific name: Echinochloa), and a weed control method using the same.

[Prior Art] Methods for controlling weeds and pests have evolved from conventional cultivation control methods to chemical control methods due to the development of chemistry about 100 years ago. In particular, DDT in the mid-1900s
With the dramatic development of synthetic organic pesticides, including
World food production has rapidly improved as it has become possible to increase crop yields, improve quality, and save labor in farming.

However, over the past few years, serious problems have arisen, such as environmental pollution caused by the use of synthetic organic pesticides, and a decrease in control effectiveness due to the appearance of pathogenic microorganisms and insect pests that have acquired drug resistance. Therefore, the development of synthetic pesticides in recent years has clearly become oriented towards high performance. In other words, it is not only safe for humans and animals, but also shows excellent effects at low doses, and has sufficient consideration for persistence, environmental pollution, etc. On the other hand, organic farming methods, in which crops are grown without the use of synthetic organic pesticides, have recently become popular. In this way, the effects of organic synthetic pesticides on the human body and the natural environment have been widely discussed, and in recent years, interest in biopesticides has increased significantly, and research and development has begun to be carried out widely in general. I was able to become For example, the establishment of a comprehensive control system that combines biological control using natural enemies or cultivation control that takes into consideration cultivation systems such as crop rotation.

Against this background, there is a strong desire to establish a biological control method. In particular, there is great demand for the development of microbial pesticides that directly utilize the living organisms of microorganisms or microbial pesticides that utilize physiological viscosity substances produced by microorganisms. In the field of herbicides, research on microbial herbicides that utilize pathogenic microorganisms against weeds has been intensively conducted in the United States in recent years.

Microbial herbicides that have already been commercially available include Teuaine (Brand name of Abbott) and Corego (Brand name of Ecodiene), which are used to control Strangerbein and Northern Shoint hedgie, respectively. Furthermore, Mycosien is about to commercialize a microbial herbicide that will be effective in controlling sicklepot in peanut and quiz fields. However, research and development of microbial herbicides has not progressed in Japan. Therefore, no microbial herbicide or microbially sourced herbicide is known that targets Novieum, which is a harmful weed in the cultivation of major grains such as rice and wheat.

[Invention or problem to be solved]

The present invention solves the above-mentioned current disadvantages in crop production and provides a new weed control means to replace synthetic pesticides. That is, we have discovered Drechlera bacteria as a pathogenic microorganism that is effective for controlling Novieum, which is a harmful weed, in the cultivation of useful plants such as rice and wheat, and weed control agents and control agents containing the viable cells or metabolites thereof provide law.

(Means for Solving the Problems) The inventors of the tree focused on pathogenic microorganisms against Novieum, with the aim of controlling Novieum, which is an important weed in rice fields and upland fields, and as a result of searching for many microorganisms, they found that they The present inventors have discovered that a pathogenic microorganism or filamentous fungus of the genus Drechslera that exhibits herbicidal activity against crops such as rice and wheat, but is not pathogenic to crops, such as rice and wheat, is abundant in the genus Drechslera, leading to the completion of the present invention.

The field grass that is the object of the present invention is a plant belonging to the family Poaceae, Echinochloa, and specifically, the grass field grass that is the subject of the present invention is the plant that belongs to the Poaceae family, Echinochloa.
icola), F. chinochl
oa crus-gall+ var.

Echinoc formosensis, Echinoc
hloa crusgalli var, crus-
galli) or Echinoch
loa crus-galli var, prati
cola) or there is.

= 1 - In other words, the present invention isolates pathogenic microorganisms from the lesions of spontaneously diseased No. japonica, and isolates these isolated microorganisms that are pathogenic to No. japonica and are useful for confining rice. New weed control agents of the genus Trechuslera found by searching for microorganisms that are not pathogenic to plants, and which are characterized by containing the raw form or its metabolites, and miscellaneous products thereof 1J [It provides a pest control method.]

The pathogenic microorganism according to the present invention was selected by conducting a herbicidal activity test and a parasitic power test against wild grass and rice on a strain that was pure isolated from a naturally diseased plant. As a result of identifying the six selected pathogenic microorganisms based on morphology, we found that Drechlera monoceras (Drech
slera monoceras) 3 strains (MH-001
5, MH-2653, MH-2Ei79), Drechslera ravenelli
lii) 2 strains (MH-0042, MH-0060),
Drechslera poa
) It was recognized that the strain was classified as strain 1 (MH-0122).

The weed control agent of the present invention that acts only on wild grasses is
- Any of the Drexlera bacteria found in the above can be used.

There are two ways to use Drechlera bacteria as a weed control agent: directly using cultured viable cells, and after culturing the cells, sterile-filtering the culture solution and using the metabolites.

The former method involves culturing spores of the genus Trechuslera in a nutrient medium and incubating them with TritonX-10.
It is used as a weed control agent by suspending it in an aqueous solution of a nonionic surfactant such as Tween 80 or Tween 80.

Spores can be obtained from cultures cultured using either liquid or solid media. That is, when using a liquid medium, the mycelia are inoculated into a potato dextrose liquid medium or an oatmill liquid medium, the cells are allowed to grow, the bacteria are collected, the resulting mycelium is crushed, and then spread on a filter paper and left to stand. It is possible to form spores by If a solid medium is used, the spores can be isolated by culturing the bacterial cells on a potato textulose agar medium or an oatmilk agar medium, and then removing the aerial mycelia with distilled water.

On the other hand, the latter method using metabolites of bacterial cells is i'IB
After culturing the i body in a potato textulose liquid medium, it is silently filtered, and the filtrate is used as a weed control agent.

By mass culturing the Drechlera spp. of the present invention to efficiently obtain spores and operating the process in an aseptic manner, it is possible to produce effective microbial weed control agents and microbially sourced weed control agents. These weed control agents, when sprayed before and after transplanting rice to paddy fields, have a herbicidal effect only on wild grasses, and are highly non-pathogenic to useful plants such as rice, wheat, barley, and corn. It has selective herbicidal activity and can be used safely without worrying about environmental pollution.

(Examples) The disease fFf and microorganisms of the genus Drechslera related to the present invention will be specifically explained below using examples, but the invention is not limited thereto.

Example 1 Analysis and identification of effective pathogenic microorganisms 1) Isolation method of pathogenic microorganisms A spontaneously diseased wild grass was collected from a rice field, a 10-20 mm section was prepared around the lesion, and it was soaked in a 70% ethyl alcohol aqueous solution. After 1 to 2 seconds of immersion, the surface of the wild grass section was sterilized by immersing it in an aqueous sodium hypochlorite solution with an effective chlorine concentration of 2% for 10 minutes. The surface-sterilized Noviae sections were washed three times with sterile distilled water, placed on a non-nutrient agar medium, and cultured for 72 hours in a thermostat at 25°C. Single thread separation was performed and pure separation was performed on a nutrient medium. The obtained isolated microorganisms were used to test herbicidal and parasitic properties against wild grasses and pathogenicity against rice.

2) Assay of herbicidal activity of isolated microorganisms against wildflowers and rice. Wildflowers and rice were grown aseptically in a test tube to the 1.5 leaf stage and used as test materials. That is, after immersing wild field and rice seeds in a 70% ethyl alcohol aqueous solution for 1 to 2 seconds, they were soaked in a 2% available chlorine aqueous sodium hypochlorite solution for 1 to 2 seconds.
The surface was sterilized by soaking for a minute and washed three times with sterile distilled water. These seeds were sown in a test tube containing a previously prepared and sterilized B5 agar medium shown below, and grown in a plant growth chamber.

Composition of B5 basic medium: The isolated microorganisms were cultured on a plate on a potato textrose agar medium, and a bacterial flora disk prepared by punching out with a sterilized corkhole was used as an inoculum.

The bacterial flora was placed on a medium in a test tube in which wildflowers and rice were grown aseptically, and then placed in a chamber for plant growth.
After culturing for 0 days, the herbicidal activity of the microorganisms was assayed. The results are shown in Table 1.

Table 1: Herbicidal activity of isolated microorganisms against grasshoppers and rice. ++ (Note ) +++ ;Death++: Significant growth inhibition+: Slightly growth inhibition: No effect 3) Assay of parasitic power of isolated microorganisms against Novieum and rice Novel and rice were grown aseptically in a test tube until the 1.5-leaf stage. , was used as the test material. That is, seeds of wild grass and rice were surface sterilized in the same manner as in the herbicidal activity test in 2), sown in test tubes containing a previously sterilized non-nutrient liquid medium, and cultured in a plant growth chamber. On the other hand, for the isolated microorganisms, microbial disks prepared in the same manner as in the herbicidal activity test in 2) were used as an inoculum.

After the target plants were inoculated with the microbial inoculum and cultured for 10 days, the parasitic power of the microorganisms was determined. The results are shown in Table 2.

Table 2 Parasitic power of isolated microorganisms on Novieum and rice Novia Rice MH-000 MH-000 MH-001 MH-002 MH-004 MH-006 MH-012 MH-265 MH-267 5+++ 2 +++ 〇 ++ 2 ++ 3 +++ 9 +++ +++ (Note) +++ ; Withering, no effect As shown in Table 1, the microorganisms of the genus Kudrexlera of the present invention Ml+-0015, MH-0042, MH-0060
, MH-0122, Ml, -2653, MH-2679
) has strong herbicidal activity against wildflowers. Among the isolated microorganisms, there are those such as MH-0001 that are not pathogenic to wild fleas at all, and those that are pathogenic only to rice, such as MH-0007, which are highly pathogenic to both wild fleas and rice. The microorganism of the present invention was selected from a large number of microorganisms obtained. Furthermore, as shown in Table 2, the strain of the present invention has specific effects on Novieum;
/l property, it is very advantageous for use as a microbial herbicide.

4) Identification of the isolated microorganisms Assays in 2) and 3) showed 6 spare strains, namely MH-0015 and MH-0042, which showed excellent herbicidal activity and parasitic power against wild grasses and had no effect on rice. ,M)10
060 MH-0122MN-2653゜MH-26
Microorganisms were identified for 79 cases. These strains were identified by culturing the microorganisms on malt agar medium. As a result, MH-0015, MH-2653, MH-26
79 at 28℃ for 7 days, the colony size was 6 in diameter.
It reached 5-75 mm and showed irregular growth. The color of the colony is gray-black. The conidia have field marks and are 15 to 17.5μI wide and 87.5 to 127μI long.
It is 5μI and its shape is slightly curved. Conidial septa have up to 9 septa, mostly 5-7. The shape of the conidiophore is straight. Based on the above characteristics, these three types of microorganisms are
onoceras).

MH-0042 and MH-0060 have no conidia, and the size is 17 to 22 μm in width and 40 to 90 μm in length.
I, often branched. The shape of the conidia is cylindrical and some are curved, and the number of septa is 1 to 5. Based on the above characteristics, these two types of microorganisms are
Drechslera ravenelii
).

M) 1-0122, the colony size reaches a diameter of 20 to 25 InI [l] at 28°C for 7 days. The color of the colony is light gray, with a gray-green center and a gray-black underside.

Conidia have no traces and are 20 to 25μI in size.
The length is 55 to 95 μm. The septa of conidia are 5-6
It is individual. The shape of the conidiophore is straight. Based on the above ten characteristics, this microorganism is known as Drechlera pore.
slera poa).

These determinations include M, B, E11is (1971)
De+nariaceus Hyphomycete
sp, 508. CommonwealthMy
Cological In5titude, Kew,
England and M.B.

Ell is (+976) and More Dema
riaceus Hyphomycatesp, 507
．． commonwealth mycological
In5titut.

kew, England.

The Drechslera spp according to the present invention is not listed as a pathogen in the National Institute of Health's Pathogen Safety Management Regulations, and is safe for humans and animals.

Example 2 Method for producing a weed control agent containing living cells of Drexcilla genus bacteria and weed control method using the same Six isolated strains of Drexcilla genus bacteria were inoculated onto an oatmil agar medium and statically cultured at 25°C for 7 days. Ta. After this, spores were obtained by removing the aerial mycelium with distilled water, and 0.0
A weed control agent containing viable Drechslerella cells as an active ingredient was prepared by suspending them in a 5% Triton X-100 aqueous solution at a rate of 106 spores/rnll.

On the other hand, seeds of wild grass and rice were sown in soil in vinyl pots with a diameter of 10 cm, and the seedlings were grown to the 1.5-leaf stage. The above-mentioned weed control agent was dropped into the flooded pot so as to inoculate 10' Drechslera spores, and cultivation was carried out in an artificial climate room maintained at 30°C during the day and 25°C at night.
I did it for 0 days. The results are shown in Table 3.

Table 3 Selective herbicidal action microorganisms of weed control agents containing viable cells of Drexlera genus Noviea Rice MH-001 MH-004 MH-006 MH-012 MH-265 MH-267 5+++ 2 + + + 0 +++ 2 + ++ 3 +++ 9 +++ (Note) +++; Death++; Significant growth inhibition+: Slight growth inhibition-;No effect As a result of the test, the pathogenic microorganisms of the genus Drechlera related to the present invention M+, -0015, MH-0042, MH-006
0, MH0+22. MH-2653, MH-2679
showed excellent pathogenicity against wildflowers, and no effects on rice were observed.

Example 3 Drechs
Method for producing a weed control agent containing MH-2653 as an active ingredient and weed control method using the same Pathogenic microorganism according to the present invention Drechslera monoceras (Drechslera monoceras) MH-2653
-2F+53 in potato textulose liquid medium 100
The inoculum was inoculated into ml and cultured at 25°C for 7 days. After culturing, the resulting pine tote mycelium was homogenized, spread on filter paper, and left for 3 days to form spores. A weed control agent was prepared using the spores in the same manner as in Example 2.

On the other hand, 50 wild grasses were sown in each of three 115,000 a Wagnerbots and grown to the 1.5 leaf stage.

105.106.107. in each flooded pot.
108 Drexlera Mono Seras (Dr.
echslera monoceras) MH-26
The above weed control agent was added dropwise to inoculate the plants with 53 spores, and the plants were grown in a greenhouse at a temperature of 15 to 35° C. After 30 days, the herbicidal activity was determined based on the percentage of dead plants. The results are shown in Table 4.

As a result of the test, Drechslera monoceras MH according to the present invention
-2653 showed excellent herbicidal activity against wildflowers.

Table 4 Herbicidal activity inoculum amount (spores/pot) of Drexlera MH-2653 Control rate (%) 0,
0 1 x 1 05 541 x 1
06 86 1xlO' 100 1 , static culture was performed at 25°C. Thereafter, the mat-like mycelium was homogenized in a culture solution, and the filtrate was further filtered using a membrane filter, and the filtrate was compressed to 11A and used in a test as a weed control agent.

On the other hand, a non-nutrient liquid medium 511 which had been surface sterilized using the same method as the herbicidal activity assay of Example 1 and was previously sterilized was prepared using a non-nutrient liquid medium 511.
I1. The seeds were sown in test tubes containing the following ingredients and grown in a plant growth chamber until the 1.5 leaf stage. Add 0.5 mu of the above weed control solution to the test tube containing the wildflower plant, and add IO.
After growing for one day, herbicidal activity was assayed. The results are shown in Table 5.

Table 5 Herbicidal activity of weed control agent containing metabolites of Drexlera bacteria against wild grass Herbicidal activity Microorganisms MH-0001 MH-0007 MH-0015+++ MH-0042+++ MH-0060++ MH-0122++ MH-2653 +++ MH-2679+++ (Note) +++;++ ++;Results of tests showing significant growth inhibition+, slight growth inhibition, and no effect, indicate that the microorganisms related to the present invention are Trechuslera MH-0015, MH-0042, MH-0080, M
The metabolites of H-0122゜MH-2653MH-2679 exhibited significant herbicidal activity against wild grasses.

Example 5 Testing of the pathogenicity of Drechlera to major crops It was confirmed that the pathogenic microorganism Drechlera according to the present invention is not pathogenic to other useful plants. The same method as in Example 4 was used for rice, wheat, barley, and corn. The results are shown in Table 6.

Table 6 Pathogenic microorganisms of Drexlera on major crops Rice Wheat Barley Corn Ml+
-0015 MN-0042 MH-0060 MH-0122 MH-2653 MH-2679 (Note) +++; Death ++; Significant growth inhibition +: Slight growth inhibition; No effect As a result of the test, the Drechlera spp. related to the present invention: It was found that it has no pathogenicity to rice, wheat, barley, and corn, and it was confirmed that it can be used as a microbial herbicide.

(Effects of the Invention) The pathogenic microorganism Drechlera according to the present invention exhibits selective pathogenicity to wild plants, and by using this microorganism as an inoculum, it can be used without affecting other useful plants. , can eliminate weeds, which are important weeds.

Furthermore, the pathogenic microorganisms according to the present invention are selected from microorganisms that inhabit the natural world, and can be used safely without the concern of environmental pollution caused by synthetic pesticides.

Claims (42)

[Claims] (1) Echinochloa (Ech) is not pathogenic to useful plants.
A weed control agent characterized by containing a Drechslera bacterium (Drechsleraspp.) that is pathogenic to the genus Inochloa. (2) 10 viable cells of Drexlera in 1 ml of solution
The weed control agent according to claim (1), characterized in that the weed control agent consists of a suspension at a ratio of ^4 to 10^9. (3) The weed control agent according to claim (2), wherein spores are used as viable cells of Drexlera. (4) The pathogenic microorganism Drechslera monoceras (Drechslera monoceras)
The weed control agent according to claim (1), which is a new strain of . (5) Pathogenic microorganism Drec
hsleramonoceras) is MH-0.
The weed control agent according to claim (4), wherein the weed control agent is 015 (KAIKOKEN BIYORI NO. 10785). (6) Pathogenic microorganism Drec
MH-2, a new strain of Hsleramonoceras
The weed control agent according to claim (4), characterized in that the weed control agent is 653 (Feikoken Kyokuyori No. 10786). (7) Pathogenic microorganism Drexlera monoceras (Drec
MH-2, a new strain of Hsleramonoceras
The weed control agent according to claim (4), characterized in that the weed control agent is No. 679 (Keikoken Kyokuyori No. 10982). (8) Drechslera spp. is a pathogenic microorganism, Drechslera ravenelii.
The weed control agent according to claim 1, which is a new strain of. (9) The weed control agent according to claim (8), wherein the new strain of the pathogenic microorganism Drechsleraravenelii is MH-0042 (Feikoken Bokuyori No. 10367). (10) Pathogenic microorganism Drec
hsleraravenelii) is a new strain called MH-0.
The weed control agent according to claim (8), characterized in that the weed control agent is 060 (Feikoken Kyokuyori No. 11033). (11) The weed control agent according to claim (1), wherein the Drechslera bacterium is a new strain of the pathogenic microorganism Drechslerapoa. (12) A new strain of the pathogenic microorganism Drechslerapoa is MH-01.
The weed control agent according to claim 11, characterized in that the weed control agent is No. 22 (Feikoken Kyokuyori No. 10981). (13) Echinochloa (Ec) is non-pathogenic to useful plants.
A weed control agent characterized by containing a metabolite of a Drechslera bacterium (Drechsleraspp.) that is pathogenic to the genus Hinochloa. (14) The pathogenic microorganism Drechslera monocera (Drechslera monocera)
The weed control agent according to claim (13), which is a new strain of s). (15) Pathogenic microorganism Drexlera monoceras (Dre
chsleramonoceras) is a new strain of MH-
The weed control agent according to claim 14, characterized in that the weed control agent is 0015 (KAIKOKEN BIKIYO NO. 10785). (16) Pathogenic microorganism Drexlera monoceras (Dre
chsleramonoceras) is a new strain of MH-
The weed control agent according to claim 14, wherein the weed control agent is No. 2653 (Keikoken Kyokuyori No. 10786). (17) Pathogenic microorganism Drexlera monoceras (Dre
chsleramonoceras) is a new strain of MH-
The weed control agent according to claim 14, wherein the weed control agent is No. 2679 (Keikoken Kyokuyori No. 10982). (18) Drechslera spp. is a pathogenic microorganism called Drechslera ravenelii.
The weed control agent according to claim (13), which is a new strain of the following. (19) Pathogenic microorganism Drec
hsleraravenelii) is a new strain called MH-0.
The weed control agent according to claim 18, characterized in that the weed control agent is 042 (Feikoken Kyokuyori No. 10367). (20) Pathogenic microorganism Drec
hsleraravenelii) is a new strain called MH-0.
The weed control agent according to claim 18, wherein the weed control agent is 060 (Keikoken Kyokuyori No. 11033). (21) The weed control agent according to claim (13), wherein the Drechslera bacterium is a new strain of the pathogenic microorganism Drechslerapoa. (22) A new strain of the pathogenic microorganism Drechslerapoa is MH-01.
The weed control agent according to claim 21, characterized in that the weed control agent is No. 22 (Feikoken Kyokuyori No. 10981). (23) Echinochloa (Ec
A weed control method characterized by using a Drechslera bacterium (Drechsleraspp.) that is pathogenic to the genus Hinochloa. (24) The pathogenic microorganism Drechslera monocera (Drechslera monocera)
The method for controlling weeds according to claim (23), which is a new strain of s). (25) Pathogenic microorganism Drexlera monoceras (Dre
chsleramonoceras) is a new strain of MH-
The weed control method according to claim 24, wherein the weed control method is the weed control method according to claim 24. (26) Pathogenic microorganism Drexlera monoceras (Dre
chsleramonoceras) is a new strain of MH-
The weed control method according to claim 24, characterized in that the weed control method is No. 2653 (KAIKOKEN BIYORI NO. 10786). (27) Pathogenic microorganism Drexlera monoceras (Dre
chsleramonoceras) is a new strain of MH-
The weed control method according to claim 24, characterized in that the weed control method is No. 2679 (Keikoken Bokuyori No. 10982). (28) Drechslera spp. is a pathogenic microorganism called Drechslera ravenelii.
24. The weed control method according to claim 23, wherein the weed control method is a new strain of . (29) Pathogenic microorganism Drec
hsleraravenelii) is a new strain called MH-0.
The weed control method according to claim (28), characterized in that the weed control method is 042 (Keikoken Bokuyori No. 10367). (30) Pathogenic microorganism Drec
hsleraravenelii) is a new strain called MH-0.
The weed control method according to claim (28), characterized in that the weed control method is 060 (Keikoken Kyokuyori No. 11033). (31) The weed control method according to claim (23), wherein the Drechslera bacterium is a new strain of the pathogenic microorganism Drechslerapoa. (32) A new strain of the pathogenic microorganism Drchslerapoa is MH-01.
The weed control method according to claim 31, characterized in that the weed control method is No. 22 (Keikoken Kyokuyori No. 10981). (33) Echinochloa (Ec
1. A weed control method characterized by using a metabolite of a Drechslera bacterium (Drechsleraspp.) that is pathogenic to the genus Hinochloa. (34) The pathogenic microorganism Drechslera monocera (Drechslera monocera)
The method for controlling weeds according to claim (33), which is a new strain of s). (35) Pathogenic microorganism Drexlera monoceras (Dre
chsleramonoceras) is a new strain of MH-
The weed control method according to claim 34, characterized in that the weed control method is the following: (36) Pathogenic microorganism Drexlera monoceras (Dre
chsleramonoceras) is a new strain of MH-
The weed control method according to claim 34, characterized in that the weed control method is No. 2653 (KAIKOKEN BIYORI NO. 10786). (37) Pathogenic microorganism Drexlera monoceras (Dre
chsleramonoceras) is a new strain of MH-
The weed control method according to claim 34, characterized in that the weed control method is No. 2679 (KAIKOKEN BIKYORI NO. 10982). (38) Drechslera spp. is a pathogenic microorganism called Drechslera ravenelii.
34. The weed control method according to claim 33, wherein the weed control method is a new strain of ). (39) Pathogenic microorganism Drec
hsleraravenelii) is a new strain called MH-0.
The weed control method according to claim (38), characterized in that the weed control method is 042 (Keikoken Bokuyori No. 10367). (40) Pathogenic microorganism Drec
hsleraravenelii) is a new strain called MH-0.
The weed control method according to claim (38), characterized in that the weed control method is 060 (KAIKOKEN BIYORI NO. 11033). (41) The weed control method according to claim (33), wherein the Drechslera bacterium is a new strain of the pathogenic microorganism Drechslerapoa. (42) A new strain of the pathogenic microorganism Drechslerapoa is MH-01.
The weed control method according to claim 41, characterized in that the weed control method is No. 22 (Keikoken Kyokuyori No. 10981).