JPH09315918A - Weed control agent and new weed control composition containing a new strain of the genus Dolex Rera - Google Patents

Abstract

(57) [Abstract] [Problem] To enhance the herbicidal effect of Dreyxella
Provided is a weed control composition which can be sprayed more safely and labor-savingly. A not shown pathogenic to rice, Echinochloa (Echino
cloa spp. ) Plants that have pathogenicity for D.
rechslera spp. ), a surfactant, and one or more kinds of fats and oils selected from animal oils, vegetable oils and mineral oils. [Effect] The composition of the present invention shows a sufficient controlling effect against Nobie by applying a herbicide which cannot be controlled by conidia alone. The bacterium belonging to the genus Dolex Rera according to the present invention is
It is selected from the microorganisms in the natural world, and it is safe without concern about environmental pollution, which is a concern with organic synthetic pesticides.
Furthermore, these mixed compositions are labor-saving type spraying agents that can be applied by the sprayer without entering the paddy field. 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 a problem in recent years.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a weed control agent and a weed control composition containing Drechslera spp .

[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. Research and development of bio-herbicide in the field of weed control is performed actively, already Asclepiadaceae weeds in the United States, pathogenic microorganisms Phytophthora solar genus Parumirora species of strangle Vine (Morrenia odorata) (Phyt
Devine (Devi) using ophthora palmirola
ne, Abbott trade name), leguminous weeds, pathogenic microorganisms Colletotrichum genus Gros Eos polio death species of Northern joint ve pitch (Aeschynomene virginica) (Collet
Corego using otrichum gloeosporioides (Col
lego, ECOGEN brand name, etc. are on the market.
In Japan, studies are underway to use conidiospores of the genus Drexlera, which has pathogenicity to the genus Mussel, as a microbial herbicide for paddy fields. Among them, by mixing a bacterium of the genus Dreyxella and a chemical herbicide, it has been attempted 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 (JP-A-3- 219
88, JP-A-4-226905). Further, in recent years, labor-saving spraying of paddy field herbicides has been desired, and 1 kg granules and flowable agents have been developed in the field of chemical herbicides. In addition, as a further labor-saving spraying method, studies have been conducted on a throwing formulation that can be applied from paddy ridges without using tools. However, in the field of microbial herbicides, such a technique has not been sufficiently studied and a practical labor-saving spraying method has not been developed.

[0003]

DISCLOSURE OF THE INVENTION The present invention is capable of enhancing the herbicidal effect of a strain of the genus Dlexrera, rather than the method of using a chemical herbicide as described above, considering the recent safety and environmental problems of pesticides. It is an object of the present invention to provide a weed control composition which can be sprayed in a safer and labor-saving manner.

[0004]

Means for Solving the Problems As a result of diligent studies to reduce the use amount of a microbial control agent containing a bacterium belonging to the genus Drexlera without using chemical herbicides, the present inventors have found that a surfactant and various animal oils, It was found that the mixed herbicide of vegetable oil or mineral oil enhances the herbicidal action of the bacterium of the genus Dreyxella, and completed the present invention.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The bacterium belonging to the genus Dolexlera according to the weed control composition of the present invention does not show pathogenicity to rice and shows pathogenicity to plants of the genus Echinocloa spp. ( Drechslera spp. ) Is. As such, Drechs Lera Monoceras
Leramonoceras var. monoceras )
H-0015 (FERM BP-2652), MH-2653 (FERM
BP-2653), MH-2679 (FERM BP-2656), MH-
1889 (FERM BP-3410), MH-4415 (FERM BP-
3413), MH-4418 (FERM BP-3414), MH-50
11 (FERM BP-3415), MH-5017 (FERM BP-341
1), MH-5018 (FERM BP-3412), MH-551
1 (FERM BP-3417), Drechslera monocerasvar. Microsporu
s ), which is a strain belonging to MH-11110 (FERM BP-3
864), MH-121024 (FERM BP-4498), MH-
121025 (FERM BP-4499), MH-122124
(FERM BP-4500), MH-122754 (FERM BP-450
1), MH-122755 (FERM BP-4502), MH-1
22756 (FERM BP-4503), a strain belonging to Drechslera ravenelii MH-
0042 (FERM BP-2659), MH-0060 (FERM BP-
2657), MH-2883 (FERM BP-3408), MH which is a strain belonging to Drechslera poa.
-0122 (FERM BP-2655), MH-2781 (FERM B
P-3407) and MH-2895 (FERM BP-3409) can be exemplified. All of these strains were located at 1-1 East Higashi, Tsukuba City, Ibaraki Prefecture.
It has been entrusted with the entrustment number to the Institute of Biotechnology, Institute of Biotechnology, Ministry of International Trade and Industry, located at No. 3. In the weed control composition of 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, and preferably 10 ⁶ to 10 ¹³ .

Animal and vegetable oils which are oils and fats according to the present invention include rice bran oil, corn oil, avocado oil, macadamie oil, jojoba oil, olive oil, castor oil, sesame oil,
Soybean oil, peanut oil, coconut oil, sunflower oil, cottonseed oil, safflower oil, linseed oil, beef oil, pork oil, whale oil and the like can be mentioned. Further, as the mineral oil which is the oil and fat according to the present invention, white oil, spindle oil, machine oil,
Examples thereof include engine oil, gear oil, turbine oil, cylinder oil, and the like, but are not limited to these. The content of animal oil, vegetable oil, or mineral oil is 1 to 90% by weight, and depends on the type of formulation.

Examples of the surfactant according to the present invention include non-ionic surfactants such as dialkylsulfosuccinate, polyoxyethylene alkyl ether, polyoxyethylene fatty acid ester, polyoxyethylene fatty acid amide, lauryl sulfate and alkylnaphthalene. Examples thereof include anionic surfactants such as sulfonates, alkylbenzene sulfonates, and tripolyphosphates, but are not limited to these. Although the content of the surfactant in the weed control composition of the present invention is 0.1 to 50% by weight,
Practically, 1 to 10% is desirable.

In order to use the weed control composition of the present invention as a herbicide, conidia and animal oils of the genus Dolex Rera,
Although the vegetable oil or the mineral oil may be used as it is, it is generally preferable to mix the conidia of the genus Dreyxella and animal oil, the vegetable oil or the mineral oil with a liquid carrier and prepare an oil solution for use. Examples of the liquid carrier include various organic solvents such as decane and dodecane, water and the like, animal oil,
Vegetable oil or mineral oil may be used as it is as a carrier.

Further, the composition of the present invention, as an auxiliary agent,
Surfactants, binders, stabilizers and the like which are usually used in horticultural chemicals may be added alone or in combination as required. The content of the auxiliary agent is 0 to 80% by weight.

As the weed control mechanism of the weed control composition of the present invention, it is presumed that the surface of the plant tissue is altered by the animal oil, the vegetable oil or the mineral oil to facilitate the infection of the genus Drexella. Further, the surfactant is necessary for uniformly dispersing the animal oil, the vegetable oil or the mineral oil in the paddy water. When the weed control composition of the present invention is used in the field, the amount of conidia of the bacterium of the genus Dreyxella is 10 ² to 10 ¹⁵
The number of pieces / ares is preferably 10 ⁶ to 10 ¹² pieces / ares.

The weed-controlling composition according to the present invention, when applied to the fly, has a synergistic effect which is unthinkable when the herbicide effect is applied alone. It is possible to control fly by controlling the amount.

Further, when the oil agent of the present invention is dripped from the ridge, the oil film spreads the water surface, and conidia are uniformly dispersed in the paddy field accordingly. Therefore, the sprayer can spray the oil agent without entering the paddy field.

[0013]

[Examples] Since the microorganisms according to claims 4 and 5 are new varieties according to our classification, first, a method for separating / selecting and identifying these new strains is shown, and then weeds according to the present invention. Formulation examples of the control composition are shown below, but the present invention is not limited thereto.

[Test Example 1] Separation / Selection Method and Identification of Microorganisms 1) Separation Method of Microorganisms Naturally occurring noviers are collected, and 1
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. After that, the hyphae of the grown fungus are separated into single hyphae under a stereomicroscope and purely separated on a nutrient medium.
Over 7,000 strains were obtained. Strain MH-1110 as a representative of a new variety of the present invention, which is a novel microorganism.
10, MH-121024, MH-121025, MH
-12246, MH-122752, MH-12275
5, 122756, MH-122757 have been deposited at the Institute of Biotechnology and Industrial Technology. The isolates were tested for pathogenicity to Nobie and safety to rice.

2) Assay of pathogenicity of isolated fungus for novier and safety for 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 was subjected to plate culture on a potato-dextrose agar medium at 25 ° C. for 4 days, and the outer edge portion of the lawn was punched with a sterilized 5 mm cork borer to use as an inoculum source. Using. The flora disc was inoculated into the medium in a test tube in which novier and rice were grown, and 2
After culturing at 5 ° C. for 10 days, the pathogenicity of the microorganisms against Nobie and rice was evaluated according to the following four grades from − to +++. The results are shown in Table 1 (Table 1).

[0016]

[Table 1] ++: Withered ++: Significant growth inhibition +: Some growth inhibition −: No effect

3) Identification of microorganisms MH-11110, 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 the classification of Ellis, MH-11110, MH-121024, MH
-121025, MH-122124, MH-1227
54, MH-122755, and MH-122756 strains are classified into the monoceras species of the genus Drexlera, but there are differences in the size and shape of conidia, the distribution range of the number of septa, and the pathogenicity from the conventional strains. Therefore, it can be seen that it 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. To demonstrate that it differs from Monoceras, a comparison of the isozyme patterns of the enzyme was carried out by Hunter as shown below.
It was performed according to these methods. As the enzyme, α-esterase, which is not easily affected by the environment, was used. The new cultivar of the present invention and various strains for comparison were cultivated in potato-sucrose medium at 25 ° C. under dark conditions for 7 to 10 days to obtain bacterial mats. The obtained bacterial cell mat was washed with distilled water, weighed, and then freeze-dried in a -80 ° C freezer to obtain 1 to 1.5 times the volume of 0.05 M Tris-hydrochloric acid buffer (pH 7.4). And crushed. The disrupted liquid was filtered, the filtrate was centrifuged at 10,000 rpm, and the supernatant was used as a sample. The amount of protein in the sample is L
It was quantified by the owry method. A large slap gel electrophoresis layer was used at Denki Eidou Ryoken as shown in Tables 2 to 5 below, 10% acrylamide gel was prepared in the lower layer, and concentrated gel (Table 2) was prepared in the upper layer. The sample obtained by the method was overlaid so that the amount of protein was 50 μg per well, and then 2 at 30 mA in running buffer (table).
Electrophoresis was performed for a period of time.

[0018]

[Table 2]

[0019]

[Table 3]

[0020]

[Table 4]

[0021]

[Table 5] When the esterase of the gel subjected to electrophoresis was stained by a conventional method and the patterns of zymograms were compared, MH-
1111010, MH-121024, MH-12102
5, MH-12246, MH-122754, MH-1
22755 and MH-122756, as shown in FIGS. 1 and 2, Drexlera monoceras var. It was determined to be a new variant with an isozyme pattern different from that of Monoceras. Next, including these new strains, examples of the above-mentioned genus Drexella, and formulation examples and examples in which a surfactant, animal oil, and vegetable oil are mixed are shown.

[Formulation Example 1] (Oil agent) Sun extract P252 (anionic surfactant / made by Sanyo Kokusaku Pulp) 10% by weight, castor oil (made by Hanui Tesque) 80
An oil solution was obtained by adding 10% by weight of a conidial suspension containing 10 ⁶ conidia of the bacterium of the genus Dolex Rera (MH-5011) per 1 ml of the oil solution and mixing them.

[Formulation Example 2] (Oil agent) 10% by weight of Nucargen FS-1 (nonionic surfactant / manufactured by Takemoto Yushi Co., Ltd.), 85% by weight of soybean oil (manufactured by Hanai Tesque), genus Drexella (MH-1889) 5% by weight of a conidium suspension containing 10 ⁸ conidia per 1 ml of an oil solution was mixed to obtain an oil solution.

[Formulation Example 3] (Oil agent) 10% by weight of Newcalgen FS-6 (nonionic surfactant / manufactured by Takemoto Yushi Co., Ltd.), 80% by weight of olive oil, and the amount of the bacterium of the genus Dolex Rera (MH-122124). 1m of oil solution
An oil solution was obtained by mixing 10% by weight of a conidial suspension containing 10 ⁶ per liter.

[Formulation Example 4] (Oil agent) Sun extract P252 (anionic surfactant / made by Sanyo Kokusaku Pulp) 20% by weight, linseed oil (made by Hanui Tesque) 70
Conidial suspension 1 containing 10 ^{8 by} weight of conidia of the genus Dolex Rera (MH-122756) per 1 ml of the oil solution
An oil solution was obtained by mixing 0% by weight.

[Formulation Example 5] (Oil agent) Newcalgen FS-31 (anionic surfactant / manufactured by Takemoto Yushi) 10% by weight, white oil (manufactured by Sigma) 8
0 wt%, Dorekkusurera genus (MH-0060) conidia suspension 10 containing 10 ⁶ cells per oil 1ml conidia of
An oil solution was obtained by mixing the components by weight.

[Formulation Example 6] (Oil agent) 10% by weight of Nukargen FS-4 (anionic surfactant / manufactured by Takemoto Yushi) and 80% by weight of whale oil (manufactured by Hanai Tesque)
An oil solution was obtained by mixing 10% by weight of a conidial suspension containing 10 ⁸ conidia of the bacterium of the genus Dolex Rera (MH-2895) per 1 ml of the oil solution.

[Test Example 2] Herbicidal effect against paddy field weeds (pot test) Novie was sown in paddy soil filled in a pot of 1 / 1000a, and seedlings were raised until the 2-leaf stage. 10 μl of the oil solution prepared according to the method described in the above Preparation Example 19 was dropped on the water surface. It was cultivated in a greenhouse at a water depth of 5 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 shown in Table 2 (Tables 6 to 11) by the following formula (Formula 1).

[0029]

(Equation 1) Further, A to H in Table 4 of Test Example-4 represent combinations of the following animal oils, vegetable oils or mineral oils and surfactants. A: Castor oil + Newkalgen FS-1 (nonionic surfactant / Takemoto Yushi) B: Castor oil + Newkalgen FS-6 (nonionic surfactant / Takemoto Yushi) C: Palm oil + New Calgen FS-31 (anionic surfactant / manufactured by Takemoto Yushi) D: coconut oil + New Kalgen FS-4 (anionic surfactant / manufactured by Takemoto Yushi) E: cottonseed oil + Neugen EA80 (nonionic surfactant) Agent / Sanyo Kasei) F: Cottonseed oil + Sun extract P252 (anionic surfactant / Sanyo Kokusaku Pulp) G: Flaxseed oil + Solpol 7655 (anionic surfactant / Toho Kagaku) H: Flaxseed oil + Nucargen EX-70 (Anionic surfactant / Takemoto Yushi)

[0030]

[Table 6] *: Animal oil, vegetable oil or mineral oil **: Surfactant

[0031]

[Table 7] *: Animal oil, vegetable oil or mineral oil **: Surfactant

[0032]

[Table 8] *: Animal oil, vegetable oil or mineral oil **: Surfactant

[0033]

[Table 9] *: Animal oil, vegetable oil or mineral oil **: Surfactant

[0034]

[Table 10] *: Animal oil, vegetable oil or mineral oil **: Surfactant

[0035]

[Table 11] *: Animal oil, vegetable oil or mineral oil **: Surfactant From Table 2, it can be seen that the mixed composition of the bacterium of the genus Dreyxella, animal oil, vegetable oil or mineral oil and surfactant according to the present invention is used when conidia alone is applied. In comparison, the herbicidal effect cooperatively increased.

[Test Example 3] Spreadability test A rectangular (11 m x 9 m, 99 m ² ) test section was prepared in a paddy field and seeded with Nobie. When Nobie was grown in the 1-leaf stage, it was prepared according to Formulation Example-1 and 30 ml of an oil solution containing 10 ⁸ conidia per 1 ml was dropped at a point 1 m from both the long side and the short side of the test plot. When observation observation was carried out 25 days after the treatment, nobies were not observed in the test plot. In the untreated plot prepared adjacent to the test plot, 25 Nobies per m ² were observed during the survey period. From these results, it was considered that the conidia in this preparation, which had been subjected to the dropping treatment, spread to the entire surface of the test section and killed the Nobie. Test Example 2 shows that the oil agent according to the present invention is a labor-saving spray agent that can be applied from the ridge.

[0037]

EFFECTS OF THE INVENTION The mixed composition of the bacterium of the genus Dreyxella, animal oil, vegetable oil or mineral oil, and surfactant according to the present invention has a herbicidal application rate which cannot be controlled by conidia alone, and is sufficient for Nobie. It shows a controlling effect. The bacterium belonging to the genus Dolexlera according to the present invention is selected from microorganisms in the natural world, and is safe without fear of environmental pollution which is a concern with organic synthetic pesticides. Furthermore, these mixed compositions are labor-saving type spraying agents that can be applied by the sprayer without entering the paddy field. 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 a problem in recent years. As described above, the combined use of the surfactant and the animal oil, the vegetable oil, or the mineral oil made it possible to reduce the use amount of Drexlera and to stabilize the effect without using any chemical herbicide.

[Brief description of drawings]

FIG. 1 is a view showing a zymogram of esterase of a bacterium of the genus Dolexrella of the present invention.

FIG. 2 is a view showing a zymogram of esterase of a conventional variant of a genus Dolex Rera.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tatsuo Niimi 1144 Togo, Mobara-shi, Chiba Prefecture Mitsui Toatsu Chemical Co., Ltd. (72) Tomoko Ooka 1144, Togo, Mobara-shi, Chiba Prefecture Mitsui Toatsu Chemical

Claims (9)

[Claims] 1. A genus Echino that does not show pathogenicity in rice.
cloa spp. ) Plants that have pathogenicity for D.
rechslera spp. ), a surfactant, and one or more kinds of fats and oils selected from animal oils, vegetable oils and mineral oils. 2. A bacterium belonging to the genus Dolex Rera is Dolex Rera.
Monoceras Drechslera monoceras var.
The composition for controlling weeds according to claim 1, which is a strain belonging to monoceras ). 3. Strains belonging to Drechslera monoceras var. Monoceras are MH-0015 (FERM BP-2652) and MH-265.
3 (FERM BP-2653), MH-2679 (FERM BP-265
6), MH-1889 (FERM BP-3410), MH-441
5 (FERM BP-3413), MH-4418 (FERMBP-341
4), MH-5011 (FERM BP-3415), MH-501
7 (FERM BP-3411), MH-5018 (FERM BP-3412)
Or it is MH-5511 (FERM BP-3417), The weed-controlling composition of Claim 2 characterized by the above-mentioned. 4. A bacterium belonging to the genus Dolex Rera is Dolex Rera.
Monoceras v Drechslera monoceras v
ar. microsporus ), and the weed control composition according to claim 1, which is a strain belonging to 5. A strain belonging to Drechslera monoceras var. Microsporus is MH-11110 (FERM BP-3864), MH.
-121024 (FERM BP-4498), MH-121025
(FERM BP-4499), MH-122124 (FERM BP-450
0), MH-122754 (FERM BP-4501), MH-1
22755 (FERM BP-4502) or MH-122756
(FERM BP-4503), The weed control composition according to claim 4, which is characterized by being (FERM BP-4503). 6. A bacterium belonging to the genus Dolex Rera is Dolex Rera.
The weed control composition according to claim 1, which is a strain belonging to Raveneri (Drechsleraravenelii). 7. The Drechslera
strain belonging to ravenelii is MH-0042 (FERM BP-
2659), MH-0060 (FERM BP-2657) or MH-
2883 (FERM BP-3408), The composition for controlling weeds according to claim 6. 8. A bacterium belonging to the genus Dolex Rera is Dolex Rera.
The weed control composition according to claim 1, which is a strain belonging to Pore ( Drechslera poa) . 9. The Drechslera po
The strain belonging to a) is MH-0122 (FERM BP-2655),
MH-2781 (FERM BP-3407) or MH-2895
(FERM BP-3409), The composition for controlling weeds according to claim 8, which is (FERM BP-3409).