JPH08175917A - Microbial weed controlling composition - Google Patents

Abstract

PURPOSE: To obtain a microbial weed controlling composition capable of reducing the amount of a microbial controlling agent containing a mold of the genus Drechslera and manifesting synergistic effects by combining the mold strain of the genus Drechslera with 2,2'-dipyridyl as a syngergistic substance capable of enhancing herbicidal effects thereof. CONSTITUTION: This microbial weed controlling composition is obtained by adding 2,2'-dipyridyl as a synergistic substance to a microbial controlling agent, comprising a mold strain of the genus Drechslera and capable of manifesting effects on the genus Echinochloa without manifesting the phytotoxicity to useful plants. The controlling agent is capable of synergistically manifesting weeding actions with the mold of the genus Drechslera and exhibiting high herbicidal activities. This composition is capable of reducing the amounts of the respective ingredients used. The mold of the genus Drechslera is partially new, e.g. MH-0015 (FERM BP-2652) or MH-2653 (FERM BP-2653). The microorganism related to the composition is selected from microorganisms in the natural world and safe without anxiety about the environmental pollution in fear of organic synthetic agrochemicals.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention does not show pathogenicity to useful plants but pathogenic to the genus Echinocloa spp. Drechslera sp.
p. ) It relates to a weed control composition containing a bacterium and 2,2′-dipyridyl.

[0002]

2. Description of the Related Art In recent years, the influence of chemical pesticides on the human body and natural environment has come to be regarded as a problem, and interest in biological pesticides is increasing. In the field of weed control, research and development of bioherbicides have been actively conducted, and in the United States, weeds and weeds, Stranglewein (Morrenia o.
pathogenic microorganisms of the genus Phytophthora palmir
devine (trade name of Abbott company) using ola), legume weeds, Northern joint vetch (Aeschynomene virginic)
a) Pathogenic microorganisms of the genus Colletotrichum gloeosp
Collego using Orioides)
o, product name of Ecogen Co., Ltd., etc. are on the market. In Japan, studies are being conducted on the use of filamentous fungi conidia of the genus Drexlera, which has pathogenicity for the genus Mussel, as a microbial herbicide for paddy fields. Among them, it has been attempted to mix filamentous fungus of the genus Dolexlera with a chemical herbicide to enhance the effect on the weed genus due to its synergistic effect, and to control weeds other than the weed genus at the same time (Japanese Patent Laid-Open No. 3-212058). -219
88, JP-A-4-226905).

2,2'-dipyridyl is an inhibitor of chlorophyll and heme biosynthesis in vivo. This compound alone is a reagent for biochemical experiments that accumulates porphyrins in plant tissues and causes cell membrane destruction and cell content leakage by photosensitization. Since the herbicidal effect is observed when this compound is used at a high concentration, some research institutions are currently studying the use of this compound as a herbicide, but have not been put to practical use.

[0004]

[Problems to be Solved by the Invention] Considering the recent safety and environmental problems of pesticides, we searched for synergistic substances that enhance the herbicidal effect of filamentous fungus strains of the genus Dolexella, and provide a safer and more practical weed control composition. The task is to do.

[0005]

Means for Solving the Problems As a result of intensive investigations by the present inventors to reduce the amount of microbial control agent containing a D. filamentous fungus, the D. Lella filamentous fungus can be mixed with 2,2'-dipyridyl. It was found that the herbicidal action is synergistically exerted with and that the herbicidal activity is high, the present invention was completed. That is, the present invention refers to the genus Echinocl.
oa spp. ) And a 2,2′-dipyridyl compound, which is a weed control composition containing Drechslera spp.

[0006] The useful plant of the present invention does not show pathogenicity, but does show pathogenicity to the genus Echinocloa spp.
p. ) [MH-0015 (FERM BP
-2652), MH-2653 (FERM BP-26
53), MH-2679 (FERM BP-265)
6), MH-1889 (FERM BP-3410),
MH-4415 (FERMBP-3413), MH-4
418 (FERM BP-3414), MH-5011
(FERM BP-3415), MH-5017 (FE
RM BP-3411), MH-5018 (FERM
BP-3412), MH-5511 (FERM BP-
3417), MH-0042 (FERM BP-265
9), MH-0060 (FERM BP-2657),
MH-2883 (FERM BP-3408), MH-
0122 (FERM BP-2655), MH-278
1 (FERM BP-3407), MH-2895 (F
ERM BP-3409)] is disclosed in JP-A-3-219883.
It is known from JP-A-4-360678 and JP-A-4-360678, and some of them are new.

2, which is another component according to the present invention
2'-dipyridyl is a known compound.

[0008] The weed control composition according to the present invention shows a synergistic effect which cannot be predicted from the effect of each of the bacterium of the genus Dolexrella and 2,2'-dipyridyl with respect to the control effect of the genus Echinocloa spp. It has become possible to reduce the amount of components used.

Although its mechanism of action is not clear, 2,2 '
-It is speculated that plant tissues damaged by dipyridyl without being killed are more easily infected by the bacterium of the genus Dlexrera than healthy plant tissues.

The weed control composition according to the present invention exhibits a synergistic effect which cannot be predicted from the respective components of the genus Dolex Rera and 2,2'-dipyridyl, and the amount of each component used can be reduced.

In order to use the weed control composition according to the present invention as a herbicide, the cells of the genus Drexlera and 2,
Although 2'-dipyridyl may be used as it is, generally, the cells of the bacterium of the genus Dolexlera and 2,2'-dipyridyl are mixed with an inert solid carrier or liquid carrier to prepare a wettable powder, a flowable agent or a liquid agent. It is desirable to prepare it for use.

The carrier is usually used for horticultural agents, and may be solid or liquid as long as it is biologically inactive, and is not limited to a particular carrier. For example, solid carriers include clay, talc,
Examples thereof include mineral powders such as bentonite, calcium carbonate, diatomaceous earth and white carbon, vegetable powders such as soybean powder and starch, and polymer compounds such as polyvinyl alcohol and polyalkylene glycol. Examples of the liquid carrier include various organic solvents such as decane and dodecane, vegetable oil, mineral oil, water and the like.

In the weed control composition according to the present invention, the content of the bacterium belonging to the genus Dreyxella is 10 ² to 10 ¹⁵ as conidia per 1 kg of the preparation, preferably 10 ⁶ to 10 ¹² .

The content of 2,2'-dipyridyl in the weed control composition of the present invention is 0.1 to 50% by weight in a wettable powder or a liquid formulation, and 0.01 to in a flowable formulation.
It is 10%.

Further, as the auxiliaries, surfactants, binders, stabilizers and the like usually used in horticultural chemicals can be used alone or in combination as required. The content of the auxiliary agent is 0 to 80% by weight.

When the weed-controlling composition of the present invention is used in a field, the amount of conidia of the genus Dolex Rera is 10 ²
-10 ¹⁵ pieces / R, preferably 10 ⁶ -10 ¹² pieces /
It is Earl.

The weed-controlling composition of the present invention, when applied to the fly, produces a synergistic effect that is unthinkable when the herbicidal effects are applied individually, and the amount of conidia is lower than expected. It is possible to control millet with a low dose.

[0018]

[Examples] First, as a reference example, a method for separating, selecting and identifying a new strain of the genus Dorexella related to the weed control composition of the present invention will be shown. In addition, 2,2'- used in the following tests
Dipyridyl was purchased as an experimental reagent from Wako Pure Chemical Industries, Ltd.

Test Example Method for Separation / Selection of Microorganisms and Identification 1) Method for Separation of Microorganisms Naturally occurring Noviers were collected and mainly diseased
A tissue section of 0 to 20 mm was prepared, and surface sterilization was performed with a 70% ethyl alcohol aqueous solution and a sodium hypochlorite aqueous solution having an effective chlorine concentration of 2%. 3 with sterile distilled water
After washing twice, the plate was placed on an agar medium and static culture was carried out at 10 ° C. for 72 hours. Then, the hyphae tips of the grown filamentous fungi were separated into single hyphae under a real microscope and purely separated on a nutrient medium to obtain a surplus of 7,000 strains. Among them, MH-11110 and MH-121 are novel microorganisms according to the present invention.
024, MH-121025, MH-12246, MH
-122752, MH-122755, 122756,
Each strain of MH-122757 has been deposited at the Institute of Biotechnology and Industrial Technology. The isolated filamentous fungi were tested for pathogenicity to Nobie and safety to rice.

2) Assay of Pathogenicity of Isolated Filamentous Fungus to Novier and Safety to Rice Nobie and rice (variety: Nihonbare) were aseptically grown in a test tube to prepare test materials. That is, the seeds of Nobie and rice are sterilized with an aqueous 70% ethyl alcohol solution and an aqueous sodium hypochlorite solution having an effective chlorine concentration of 2%, washed three times with sterile distilled water, and seeded in a pre-sterilized medium in a test tube. The seedlings were raised up to the 1.5 leaf stage in a plant growing chamber.

On the other hand, the isolated microorganism of the present invention is potato.
A flora disk prepared by plating on dextrose agar medium at 25 ° C. for 4 days and punching the outer edge of the flora with a sterilized 5 mm cork borer was used as an inoculum source.

The bacterial lawn disc was inoculated into a medium in a test tube in which nobie and rice were grown, and cultured at 25 ° C. for 10 days in a chamber for growing plants. The evaluation was made in the following four grades from-to +++. The results are shown in Table 1 (Table 1). ++: Withered ++: Significant growth inhibition +: Some growth inhibition −: No effect

[0023]

[Table 1]

3) Identification of Microorganisms MH-111010, MH-121024, MH-12
1025, MH-12246, MH-122754, M
When the H-122755 and MH-122756 strains were plated on a malt agar medium at 28 ° C for 7 days, the size of the colonies reached 65 to 75 mm and showed irregular growth. The color of the colony is grey-black, there are traces on the silk, and the size is 17-27 (majority 19-23) μ
m, length 35-110 (mostly 70-100) μm
The average value of the ratio of the major axis to the minor axis is 6.1 or less (the majority 4.
5 to 5.0). The shape is a little straight.
Most of the partition walls of the split silk are 4 to 6, and the shape of the split silk handle is straight.

On the other hand, the conventionally known Drexlera monoceras (Drexlera monoceras var.
In Monoceras), the size of conidia is 16 to 25 in width.
(Majority 17 to 20) μm, length 60 150 (majority 100 to 120) μm, ratio of major axis to minor axis (length / length
The average value of the width is 5.9 or more (the majority, 6.2 to 6.5).
Met. The shape is also slightly curved. Most of the partition walls of conidia are 4 to 10 (majority 5 to 7), and the shape of the conidia stalk is straight.

From the above characteristics, according to Eris' classification, M
H-11110, MH-121024, MH-121
025, MH-122124, MH-122754, M
The H-122755 and MH-122756 strains are classified into the monoceras species of the genus Dolexlera, but there are differences in the size and shape of conidia, the distribution range of the number of septa, and the pathogenicity of the strains. It can be seen that this is a new variety different from the conventional strain.

In addition, the new variant of the present invention is the conventional Dolex Rera monoceras var. In order to demonstrate that it differs from Monoceras, a comparison of the isozyme patterns of the enzymes was performed according to the method of Hunter et al., As shown below. As the enzyme, α-esterase, which is not easily affected by the environment, was used.

The new variety of the present invention and various strains for comparison were tested in a potato-sucrose medium at 25 ° C. under dark conditions.
After static culture for 7 to 10 days, a cell mat was obtained. The resulting bacterial cell mat was washed with distilled water and weighed, then -8
It was freeze-dried in a freezer at 0 ° C., and 1-1.5 times volume of 0.05 M Tris-hydrochloric acid buffer (pH 7.4) was added for crushing. The disrupted liquid is filtered and the filtrate is replaced with 10,000
After centrifugation at 0 rpm, the supernatant was used as a sample.
The amount of protein in the sample was quantified by the Lowry method.

Using a large slap gel electrophoresis layer, a lower layer of 10% acrylamide gel and an upper layer of a concentrated gel were prepared.
50 μg / well of the sample obtained by the above method
After overlaying so that the amount of protein would be the same as above, electrophoresis was performed in a running buffer at 30 mA for 2 hours.

Electrophoresis operation conditions: Acrylamide gel 10% gel Concentrated gel A 12 ml 1.8 ml B 9 ml-C-3 ml D 140 μl 36 μl TMED 20 μl 12 μl H ₂ O 15 ml 7.2 ml

A: acrylamide 29.8% BIS acrylamide 0.2% B: 1.5M Tris-HCl (pH 8.8) C: 0.5M Tris-HCl (pH 6.8) D: 10% ammonium persulfate

Sample buffer 0.5 M Tris-HCl (pH 6.8) 5 ml 0.05 M BPB 2 ml Glycerol 2 ml H ₂ O 28 ml

Running buffer 250 mM Tris 1.92 M glycine

Esterase of the gel subjected to electrophoresis was stained by a conventional method and the patterns of zymograms were compared. As a result, MH-11110, MH-121024, MH
-121025, MH-12246, MH-12275
4, MH-122755 and MH-122756 are shown in FIG.
And as shown in 2 and 2, Drex Rera monoceras va
r. It was determined to be a new variant with an isozyme pattern different from that of Monoceras.

Next, weed control compositions according to the present invention will be shown as examples. Example 1 (Wettable powder) Neoperex (trade name / manufactured by Kao) 2% by weight, Triton (X-100) 2% by weight, white carbon 5% by weight,
1% by weight of 2,2'-dipyridyl was added to 1 g of a conidium of the genus Dolex Rera (MH-4418 strain) per 1 g of wettable powder.
Impregnated with a suspension containing 0 ⁸ pieces, air-dried, and then diatomaceous earth 90
A wettable powder was obtained by thoroughly pulverizing and mixing the weight%.

Example 2 (Wettable powder) Neoperex (trade name / manufactured by Kao) 2% by weight, Triton (X-100) 2% by weight, Neugen EA80 (trade name /
Sanyo Kasei) 1% by weight, white carbon 5% by weight,
20% by weight of 2,2'-dipyridyl was used as a conidium of the genus Dolex Rera (MH-5511 strain) per 1 g of the wettable powder.
Impregnated with a suspension containing 0 ⁶ pieces, air-dried, and then diatomaceous earth 70
A wettable powder was obtained by thoroughly pulverizing and mixing the weight%.

Example 3 (Wettable powder) 2% by weight of Newkalgen P-150 (trade name / manufactured by Takemoto Yushi Co., Ltd.), 5% by weight of white carbon, and 1% by weight of 2,2'-dipyridyl were added to a bacterium of the genus Dolex Rera (MH-). 1111010
Strains) were impregnated with a suspension containing 10 ⁸ per 1 g of wettable powder, air-dried, and 92 wt% of diatomaceous earth was well pulverized and mixed to obtain a wettable powder.

Example 4 (Wettable powder) 2% by weight of Newcalgen P-150 (trade name / manufactured by Takemoto Yushi Co., Ltd.), 2% by weight of Solpol 3463 (trade name / manufactured by Toho Chemical Co., Ltd.), Neugen EA80 (trade name / Sanyo Kasei Co., Ltd.) 1% by weight, 2,2'-dipyridyl 20% by weight, and 1 g of wettable powder of conidia of the genus Dolex Rera (MH-122754).
After impregnation with a suspension containing 10 ⁶ per unit and air drying, 75% by weight of diatomaceous earth was well pulverized and mixed to obtain a wettable powder.

Example 5 (Wettable powder) Newkalgen TG-285 (trade name / manufactured by Takemoto Yushi) 2
% By weight, Solpol 7655 (product name / Toho Chemical) 2
%, 2,2′-dipyridyl 1% by weight, impregnated with a suspension containing 10 ⁸ conidia of the genus Dolex Rera (MH-0042 strain) per 1 g of wettable powder, air-dried, and then 95% by weight of diatomaceous earth. Was pulverized and mixed well to obtain a wettable powder.

Example 6 (Wettable powder) Neoperex (trade name / manufactured by Kao) 2% by weight, Triton (X-100) 2% by weight, Neugen EA80 (trade name /
Sanyo Kasei) 1% by weight, white carbon 5% by weight,
20% by weight of 2,2'-dipyridyl was used as a conidium of a bacterium of the genus Dolex Rera (MH-0122 strain) per 1 g of a wettable powder.
Impregnated with a suspension containing 0 ⁶ pieces, air-dried, and then diatomaceous earth 70
A wettable powder was obtained by thoroughly pulverizing and mixing the weight%.

Example 7 (Flowable Agent) 10 wt% of sun extract (P252) and 1 wt% of 2,2′-dipyridyl dissolved in 79 wt% of water were wet-milled and mixed to prepare a bacterium of the genus Dolex Rera (MH-5017). 0.4 wt% of Kelzan S (trade name / made by Kelco) dissolved in 9.6 wt% of conidial suspension containing 10 ¹⁰ conidia per ml of flowable agent was added and mixed to obtain a flowable agent.

Example 8 (flowable agent) Solpol 7566 (trade name / dissolved in 65% by weight of water)
Toho Kagaku) 10% by weight, 2,2'-dipyridyl 5% by weight Conidia suspension 10 containing 10 ⁸ conidia of the bacterium of the genus Dolex Rera (MH-0015) per 1 ml of the flowable agent
After mixing 1% by weight, wet milling and mixing were performed, and 0.4% by weight of Kelzan S (trade name / manufactured by Kelco) dissolved in 9.6% by weight of water was added and mixed to obtain a flowable agent.

Example 9 (flowable agent) Demol N (trade name / manufactured by Kao) dissolved in 79% by weight of water
10 wt% and 2,2′-dipyridyl 1 wt% were wet-milled and mixed, and a bacterium of the genus Dolex Rera (MH-121024)
Xanthan gum dissolved in 9.6% by weight of a conidial suspension containing 10 ¹⁰ conidia per 10 ml of a flowable agent.
4 wt% was added and mixed to obtain a flowable agent.

Example 10 (Flowable agent) 10% by weight of sun extract (P252) and 5% by weight of 2,2'-dipyridyl dissolved in 65% by weight of water, conidia of a bacterium of the genus Dolex Rera (MH-122756) are flowable agent 1 m.
10% by weight of conidial suspension containing 10 ⁸ per liter was mixed, wet-ground and mixed, and 0.4% by weight of gum arabic dissolved in 9.6% by weight of water was added and mixed to obtain a flowable agent. .

Example 11 (Flowable Agent) 10% by weight of Newcalgen FS-5 (trade name / manufactured by Takemoto Yushi Co., Ltd.) and 1% by weight of 2,2′-dipyridyl dissolved in 79% by weight of water were wet-ground and mixed, and Drex-Rera Genus bacteria (MH
-0060) conidia of 10 per 1 ml of the flowable agent
^A flowable agent was obtained by adding 0.4% by weight of Kelzan S (trade name / manufactured by Kelco) dissolved in 9.6% by weight of a conidial suspension containing ¹⁰ cells and mixing them.

Example 12 (Floable Agent) Conidia of a sun extract (P252) 10% by weight and 2,2′-dipyridyl 5% by weight dissolved in 65% by weight of water, and conidia of a bacterium of the genus Dolexlera (MH-2781) were used as a flowable agent 1 ml. Kelzan S dissolved in 9.6% by weight of water after mixing 10% by weight of conidial suspension containing 10 ⁸ per
A 0.4 wt% (trade name / made by Kelco) was added and mixed to obtain a flowable agent.

Test Example 1 Herbicidal effect against paddy field weeds (wettable powder) Novie seeds were sown in paddy soil filled in a pot of 1 / 1,000 a and cultivated until the 2 leaf stage. 10 ml of 100 mg of wettable powder prepared according to the method described in Formulation Example 1 above
Was dispersed in water and sprayed onto the leaves of weeds. It was cultivated in a greenhouse at a water depth of 0 cm at 35 ° C during the day and 20 ° C at night. The number of remaining individuals is counted 20 days after application, and the following formula (Equation 1) is used.
The control rates for weeds are shown in Table 2 (Tables 2 to 4).

[0048]

[Equation 1]

[0049]

[Table 2]

[0050]

[Table 3]

[0051]

[Table 4]

From Table 1, the weed-controlling composition according to the present invention synergistically increased the herbicidal effect as compared with the case where each of them was applied alone.

Test Example 2 Herbicidal Effect on Paddy Weeds (Floable Agent) Seeds of Novier were sown in paddy soil filled in pots of 1 / 1000a, and seedlings were raised to the 2 leaf stage. 100 μl of a flowable agent prepared according to the method described in Formulation Example 7 above was dispersed in 10 ml of water, and sprayed on the leaves of weeds. It was cultivated in a greenhouse at a water depth of 0 cm at 35 ° C during the day and 20 ° C at night. The number of remaining individuals was counted 20 days after application, and the control rate against weeds was calculated according to the following equation (Equation 2) in Table 3 (Table 5).
~ 7).

[0054]

[Equation 2]

[0055]

[Table 5]

[0056]

[Table 6]

[0057]

[Table 7]

From Table 3, the weed-controlling composition according to the present invention synergistically increased the herbicidal effect as compared with the case of single application.

[0059]

EFFECTS OF THE INVENTION The weed control composition according to the present invention showed an excellent synergistic effect, and showed a sufficient control effect on Nobies at application rates which cannot be controlled by each of them.
The microorganisms according to the present invention are selected from microorganisms in the natural world, and are safe with little concern about environmental pollution, which is a concern with organic synthetic pesticides.

Therefore, the weed control composition according to the present invention not only contributes to crop production, but also contributes to avoiding environmental pollution and the emergence of drug-resistant weeds, which have become problems in recent years.

[Brief description of drawings]

FIG. 1 is a novel microorganism according to the present invention (Drex Rera.
Monoceras var. FIG. 3 is a view showing a zymogram pattern of esterase of (Microsporus).

FIG. 2 Conventional Drex Rera monoceras var.
FIG. 6 shows a zymogram pattern of monoceras esterase.

Claims (9)

[Claims] 1. A genus Echinacea (Ec) which does not show pathogenicity to useful plants.
hinocloasp sp. ), Which shows pathogenicity to (2) and Drechslera spp.
A weed control composition comprising dipyridyl. 2. A bacterium belonging to the genus Dolexlera is a pathogenic microorganism, Drechslera monceras.
oceras var. Monoceras). The weed control composition according to claim 1. 3. A pathogenic microorganism, Drexlera monoceras va.
r. monoceras) is MH-0015 (FER
M BP-2652), MH-2653 (FERM B
P-2653) or MH-2679 (FERM B
P-2656), MH-1889 (FERM BP-3
410), MH-4415 (FERM BP-341
3) or MH-4418 (FERM BP-341
4), MH-5011 (FERM BP-3415),
MH-5017 (FERM BP-3411), MH-
5018 (FERM BP-3412) or MH-5
The weed control composition according to claim 2, which is 511 (FERM BP-3417). 4. A bacterium belonging to the genus Dolexlera is a pathogenic microorganism, Drechslera monceras.
oceras var. The composition for controlling weeds according to claim 1, which is microsporus). 5. A pathogenic microorganism, Drechslera monoceras va.
r. microsporus) is MH-11110
(FERM BP-3864), MH-121024
(FERM BP-4498), MH-121025
(FERM BP-4499), MH-122124
(FERM BP-4500), MH-122754
(FERM BP-4501), MH-122755
(FERM BP-4502) or MH-12275
The composition for controlling weeds according to claim 4, which is 6 (FERM BP-4503). 6. A bacterium belonging to the genus Dolexlera is a pathogenic microorganism, Drechslera raveneri.
The weed control composition according to claim 1, which is nelii). 7. The pathogenic microorganism Drechslera ravenelli is MH
-0042 (FERM BP-2659), MH-00
60 (FERM BP-2657) or MH-288
7. The weed control composition according to claim 6, which is 3 (FERMBP-3408). 8. The weed control composition according to claim 1, wherein the bacterium belonging to the genus Dolexlera is a new strain of the pathogenic microorganism Drechslera poa. 9. A pathogenic microorganism, DOREX RELApore (D
RH-0122 is a new strain of rechslerapoa)
(FERM BP-2655), MH-2781 (FE
RM BP-3407) or MH-2895 (FER
MBP-3409), The composition for controlling weeds according to claim 8.