JPH03206005A - Herbicide for rice field - Google Patents

Abstract

PURPOSE: To obtain a herbicide for paddy rice field by combining α-(β- naphthoxy)propionanilide and 2,3-dihydro-3,3-dimethyl-5- benzofuranylethanesulfonate with 2-benzothiazol-2-yloxy-N-methylacetanilide, etc. CONSTITUTION: This herbicide is produced by combining (A) α-(β-naphthoxy) propionanilide effective against broad-leaved weeds, (B) 2,3-dihydro-3,3- dimethyl-5-benzofuranylethanesulfonate for plowed land and (C) one or more compounds effective against cockspur-grass and selected from 2-benzothiazol-2- yloxy-N-methylacetanilide, S-benzyl-Nethyl-N(1,2-dimethylpropyl)-thiol carbamate and 2,6-diethyl-N-(propoxyethyl)chloroacetanilide. It is applicable at an arbitrary stage from the initial sprouting stage of weeds immediately after the transplantation of rice to the growing stage of the weeds. It is safe to paddy rice plant and has high practicality.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention provides 2-benzothiazol-2-yloxy-N
-Methylacetanilide, S-pencyl-N-ethyl-
one or more compounds from the group consisting of N(1,2-dimethylpropyl)-thiol carbamate, 2,6-diethyl-N-(propoxyethyl)chloroacetanilide, and α-(β-naphthoxy)propionanilide; 2
, 3-dihydro-3,3-dimethyl-5-henzofuranylethanesulfonate as an active ingredient, and the herbicidal subectrum has an expanded herbicidal activity compared to conventional herbicides for paddy fields. This invention relates to herbicides for paddy fields.

That is, the present invention provides a herbicide for paddy fields that exhibits excellent effects against perennial weeds such as black croaker, Japanese cypress, and paddy weed, which are difficult to control with conventional herbicides, from the beginning of their emergence to the growing season.

(Prior Art) Conventionally, herbicides for paddy fields in Japan have been broadly classified into three types based on the timing of use: early, middle, and late. Also,
There are systematic treatments that use a combination of these two or three times, but recently, one-shot treatments that only require one treatment have also been developed. However, there are quite a few weeds that are difficult to control, such as perennials such as black croaker, cyperus japonica, and porphyry. However, there are currently no existing drugs that can completely control the disease.

Furthermore, when attempting to completely control these weeds using commercially available agents, the problem of chemical damage to paddy rice crops often arises depending on soil conditions and the like. For these reasons, there is a strong desire to develop a herbicide for paddy fields that is safe for paddy rice, is highly effective against weeds such as Cyperus spp., and has a long weed suppression period.

(Problems to be Solved by the Invention) The present invention provides a highly practical herbicide that can be used at any time from the onset of weed emergence immediately after rice planting to the growing season, and is safe for paddy rice. The challenge is to obtain.

[Means for solving Problem B]

In order to solve the above problems, the present inventors have conducted intensive research on mixed herbicides using α-(β-naphthoxy)propionanilide as a mixed mother agent, and found that 2-penzothiazol-2-yloxy- N-methylacetanilide, S-
Benzyl-N-ethyl-N(1,2-dimethylpropyl)-thiol carbamate, 2,6-diethyl-N-(
one or more compounds from the group consisting of broboxyethyl)chloroacetanilide and α-(β-naphthoxy)propionanilide and 2,3-dihydroxy-3,3-
By mixing with dimethyl-5-benzofuranylethanesulfonate, it can be used at any time from the beginning of weed emergence right after rice planting to the growing season, and can be used to control many paddy field weeds, including weeds that are difficult to control, such as Japanese black grub. The present invention has been completed based on the discovery that it is possible to obtain a herbicide that exhibits accurate weed control and suppressive effects on paddy rice plants and is safe for paddy rice plants.

That is, the present invention provides α-(β-naphthoxy)propionanilide (hereinafter referred to as compound (1)) and 2,3-dihydro-3,3-dimethyl-5-benzofuranylethanesulfonate (hereinafter referred to as compound (1)). 2), 2-penzothiazol-2-yloxy-N-methylacetanilide (hereinafter referred to as compound (III-1)), S-benzyl-N-ethyl-N (1.2- dimethylprobyl)-thiol carbamate (hereinafter referred to as compound (III-2)
), 2,6-diethyl-N-(propoxyethyl)chloroacetanilide (hereinafter referred to as compound (III-3)
This is a herbicide for paddy fields characterized by containing as an active ingredient a mixture of one or more compounds from the group consisting of () and ().

The active compounds contained in the composition of the present invention are all known as listed below.

Compound [I]: JP-A-46-14077 compound' (H
): JP-A-53-98936 compound (III-1):
JP-A-54-1 54762 compound (m-2): Published patent publication 58-501177 compound (III-3):
JP-A-49-54527 However, when each of these activities is used alone, there are
Both are not satisfactory.

Compound (I) has already been put into practical use, and many mixtures with other herbicides are known (Japanese Patent Laid-Open No. 61-35962).
, Japanese Patent Publication No. 59-39805, etc.). However, there are many practical problems with them. When compound (I) is used alone in paddy fields, it is effective against broad-leaved weeds such as paddy field weeds, and causes little phytotoxicity to paddy rice. However, the herbicidal effect on weeds such as field weeds and black weeds is insufficient even in pre-emergence treatment, and furthermore, almost no herbicidal effect can be expected with treatment during the growing season.

In addition, the above-mentioned compound (II) is known to have a herbicidal effect on grass weeds such as Enhaku and broad-leaved weeds such as Aohyu, as well as Hamasuke, when top-treated in the field or mixed with soil. However, (SIIORT REVIE
W OF HERBICIDES. 1986. H.O.
DOGAYA[:lHEMICAL. ．． Go. ,LT
D. ) Little is known about the herbicidal effects and target weeds for use in paddy fields.

Any of the other above-mentioned compounds (I [Ii, -2 or -3]), when used alone, exhibits a strong herbicidal effect against Japanese grasshopper, but has a weak effect on grasshoppers and the like.

On the other hand, compound (I). (II) and compound (III-1
．． 2 or -3) and its performance are not yet known.

Therefore, the present inventors investigated various combinations of the above-mentioned compounds and attempted to develop a new herbicide for paddy fields.

As a result, a mixture of the two compounds (I) and (rI) and the compound (m-], -2 or -3) in an appropriate ratio unexpectedly showed extremely significant herbicidal effects and It has been found that there is safety against and high practicality.

That is, the composition of the present invention has a mixed effect, and is highly effective not only against grass weeds such as field grass and annual broad-leaved weeds, but also against firefly.

In particular, we found extremely high herbicidal activity and durability of the effect against difficult-to-control perennial weeds such as black croaker and staghorn weed, which could not be expected from existing agents, and brought the highly practical present invention to fruition.

When the herbicide of the present invention is actually used, in order to more fully exhibit the herbicidal effect of the composition of the present invention, additives for agricultural chemicals, such as diluents, may be used to enhance or stabilize the effect, depending on the purpose of use. , surfactants, binders, stabilizers, etc., and are made into dosage forms such as fine granules, permanent agents, emulsions, granules, flowable agents, and powders using manufacturing methods commonly used in the agricultural chemical manufacturing field. can be used.

Agricultural auxiliaries here are general ones, such as diluents (liquid carriers such as fillers and solvents), surfactants (solubilizers, emulsifiers, dispersants, wetting agents), stabilizers, Examples include fixing agents, disintegrants, binders, synergists, and the like.

Examples of carriers include aromatic hydrocarbons such as xylene and methylnaphthalene, aliphatic hydrocarbons such as kerosene, alcohols such as methanol, quarrycols such as cellosolve,
Examples include ketones such as isophorone and cyclohexanone, sulfoxides such as dimethylsulfoxide, amides such as dimethylformamide, vegetable oils such as soybean oil, fatty acids, fatty acid esters, acetonitrile, and water.

Solid carriers include fine mineral powders such as kaolin clay, talc, silica, silica, calcium carbonate, bentonite, attapulgite clay, feldspar, quartz, acid clay, and white carbon, fertilizers such as potassium chloride, and urea;
Examples include sawdust, soybean meal, crushed vegetable products such as corn, and the like.

In addition, as an emulsifier or dispersant, ordinary surfactants are used, such as alkyl sulfates, alkylaryl sulfonates, dialkyl sulfosuccinates, polyoxyethylene alkylaryl ether phosphates, polycarponates, etc. Anionic surfactants, nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkylaryl ethers, polyoxyethylene polyoxybrobylene block copolymers, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, etc. Can be mentioned.

As formulation adjuvants, arginine sulfonate, alginate, polyvinyl alcohol, arabicum, CMC
(mfibrine sodium glycolate) and the like.

The amount of the active ingredient compound in the herbicide of the present invention varies depending on the formulation form, application method, and other conditions, but usually 0 parts by weight of compound (II) per part by weight of compound (I).
．． 05 to 1.0 parts, and 0.1 to 1.0 parts for compound (■-1).
0 parts by weight, 0.2 to 1.5 parts by weight for compound (m-2), and 0.05 to 0.5 parts by weight for compound (I[1-3), preferably < is compound (I) Compound (II) is 0.1 to 0.5 part, Compound (III-1) is 0.3 to 0.8 part, and Compound (III-2) is 0.5 part to 1 part by weight.
~1.0 part, 0.1 to 0.4 for compound (III-3)
Parts by weight.

〔Example〕

Next, formulation examples and herbicidal activity test examples of the herbicide according to the present invention will be given, but the present invention is not limited to these. In addition, all the mixing ratios of each component are weight ratios.

Formulation example (1): Wettable powder Compound (I) 20 parts Compound (II) 5 parts Compound (m-
])・・・・・・・・・・・・ 10 parts Tyxsol W-66 as a dispersion hydration aid・・・・・・ 10 parts (Daiichi Kogyo Seiyaku ■ trade name) Solbol 8070・・・・・・・・・・・・ 1st part (Toho Chemical ■trade name) and Carbrex #80 as carrier・・・・・・・・・ 5th part (Shionogi Pharmaceutical ■trade name) Siegrite・・・・・・・・・・・・- 49 parts (Siegrite ■ trade name) were mixed uniformly and pulverized to make a permanent agent.

Formulation Example (2) Two tablets Compound (I) 7 parts Compound (II) 1.5 parts Compound (III- 1) 3.5 parts Sodium lignin sulfonate 2 parts Sodium lauryl sulfate 1 part Bentonite
......60 parts and talc...
After thoroughly pulverizing and mixing 25 parts, adding water and kneading well, extrusion granulation was carried out, and after drying, the granules were sized to obtain a mixed granule of the present invention.

Formulation Example (3) Two tablets Compound (I) 10 parts Compound (II) 1.5 parts Compound (DI- 2)・・・・・・・・・・・・ 5 parts Sodium lignin sulfonate 2 parts Sodium lauryl sulfate 2 parts Bentonite
......55.5 parts and talc...
After pulverizing and mixing 24 parts, adding water and kneading well, extrusion granulation was carried out, and after drying, the granules were sized to obtain a granule according to the present invention.

Formulation example (4): Granules Compound (I) 10 parts Compound (II) 1.5 parts Compound (m- 3)・・・・・・・・・・・・ 2 parts Sodium lignin sulfonate 2 parts Sodium lauryl sulfate 1 part Bentonite
...60 parts and talc...
... 23.5 parts were thoroughly ground and mixed, water was added, and the mixture was thoroughly kneaded and moistened. The mixed granules of the present invention were obtained by extrusion granulation, drying, and sizing.

Formulation example (5): Granule compound (I)... Sodium lignin sulfonate... Sodium lauryl sulfate... Bentonite...・ And talc... 7 parts, 2 parts, 1 part, 60 parts, 22.5 parts are ground and mixed, water is added and mixed well, and then extruded and granulated. After drying, the particles are sized to form a base, and further, 9 of these
Compound (II) equivalent to 1.5 parts and compound (II) were added to 2.5 parts.
A mixed granule of the present invention was obtained by uniformly and simply impregnating 5 parts of I-2) and a 3-component mixture corresponding to i part of the compound (m-33).

Formulation example (6): Powder Compound (I) 10 parts Compound (II) 1.5 parts Compound (m-3 )・・・・・・・・・・・・ 2 parts Polyoxyethylene nonyl phenyl ether 0.5 parts Orin clay・・・・・・・・・86 parts were thoroughly ground and mixed to obtain a powder. Ta.

Formulation example (7): Emulsion Compound (I) 9 parts Compound (II) 1.5 parts Compound (
III-3)・・・・・・・・・・・・ 2 parts polyoxyethylene styrylphenyl ether ・10 parts Ca salt of todecylbenzenesulfonic acid ・ 3 parts dimethylformamide ・・・15 parts xylene...
......595 parts were thoroughly mixed and liquefied uniformly to obtain an emulsion.

Formulation example (8): Flowable agent Compound (I) 24 parts Compound (II) 6 parts Compound (III-3)・・・・・・・・・・・・ 6 parts Solpol 355S (Toho Chemical brand name) 1 part sodium likuninsulfonate 5 parts water
After thoroughly mixing 40 parts, wet-pulverize until the average particle size is 15 microns or less to obtain a base material for flowables, and xanthan gum...
・0.1 part water・・・・・・・・・・・・・・・・・・
17.9 parts were added to form a flowable agent.

Formulation Example (9) Single agent for control As a single agent for control and as a single agent for granule mixing treatment, the active ingredient was added to the compound (
I) 10 parts, compound (II) 1.5 parts, compound (III)
-1) A single agent of each compound was prepared as granules using 3.5 parts of compound (III-2), 5 parts of compound (III-2), and 2 parts of compound (I[I-3).

In addition, regarding the shortage of parts by weight at the time of formulation, the amount of talc blended for dilution and increase was adjusted.

In the case of paddy fields, the composition of the present invention thus formulated is preferably treated with flooded soil, and granule treatment is effective.

Increased herbicidal efficacy can be expected by using it in combination with other herbicides.

Furthermore, it can also be used in combination with insecticides, fungicides, growth regulators, fertilizers, soil conditioners, and the like.

Test example (1) Mixed effect test under rice field condition F A Wagner pot of 175,000 are was used.

After alluvial soil was added, water was added and mixed, and seeds of Japanese wild grass, Japanese grasshopper, and firefly were mixed in a 1 cm layer on the surface layer. Furthermore, cut the tubers of Urikawa and Mizugayari to a depth of 1 cm.
In addition, black bream tubers were transplanted to the surface layer 3 cm. Furthermore, after transplanting two rice seedlings (variety: 2.5 leaves of Kuchimotoharu) per pot, they were grown in a greenhouse at 20 to 30°C, and the weed onset period was 5 days after sowing. Timebie is 2.5
At the leaf stage, flooded soil was treated at a water depth of 3c+n using the single granules shown in Formulation Example (9) above so that the respective dosages would be the same. Four weeks after the chemical treatment, the herbicidal effects of each test compound on various weeds were investigated according to the following criteria. The results are shown in Tables 1 and 2. The evaluation is on an 11-point scale, and the numbers in the table are 0 for normal and 1 to 9.
indicates an intermediate stage between normal and complete withering, and 10 indicates complete withering.

Weed killing effect judgment criteria 10... Weed killing rate 95% or more (almost complete death) 9...
・Weed killing rate 90-94% 8... Weed killing rate 80-89% 7... Weed killing rate 70-79% 6... Weed killing rate 60-69% 5... Weed killing rate 50-59% 4...・Weed killing rate 40-49% 3... Weed killing rate 30-39% 2... Weed killing rate 20-29% 1... Weed killing rate 10-19% 0... Weed killing rate 9% or less (almost no effect) ) The above weed killing rate was determined by the following formula by measuring the weight of above-ground plants in the chemically treated area and the weight of above-ground plants in the non-treated area.

Weed killing rate (%) = Test example (2) Field test Common weeds in paddy fields or naturally occurring paddy fields were plowed in the usual way and fertilized (N, P2 05, K2 0, 1 each)
kg/are), plowing and leveling the land, 1 ward 5r
divided into 2.5 m x 2 m), and leaf age 2
, 5 paddy rice seedlings are considered as one plant, and the spacing between plants is 15 cm.
Transplantation was performed under conditions of a ridge spacing of 30 ClIO.

After transplantation, the water depth was maintained at 3 to 5 cm.

The chemical treatment was carried out at the 2.5 leaf stage of Japanese millet (rice planting 1).
After 4 days), the formulation example (2). The mixed granules of the present invention prepared in (3) and (4), the control single agent prepared in Formulation Example (9), and the commercially available granules were uniformly distributed by hand. The herbicidal effect and sustainability were investigated on the 45th day after spraying by actual measurement and effect evaluation according to the method described above. In addition, the actual area of the sampling survey for the amount of remaining weeds is 0 per ward within each ward.
．． 25rn' (50cm square).

The results are shown in Table 3.

(Leaving space below) Table 1 Pot test results (treatment at the beginning of weed emergence) Note) EC: Tainubier, MV: Konagi, SJ: Hotarui, SP: Urikawa, CS: Mizugaya Tsuri, EK: Kurogwai Note) Commercially available granules (Shinzan granules) Active ingredient amount 201 (β-naphthoxy)propionanilide: 7%+
Table 2 Pot test results (Taiwan millet 2.5 leaf stage treatment) [Summary of the results of Example 1 The following can be seen from the results in Tables 1 and 2.

During the growing season, commercially available pesticides have insufficient herbicidal effects against black bream, staghorn grass, etc. However, the compound [IJ
, [Ir] or [ II+ -1, -2, -3
] The dose that cannot be controlled by each single agent of compound [I] and [
■11 and [+11-1. -2. When applied in combination with -31 or -31, the herbicidal effect is significantly increased, and the herbicidal effect can be expected even when used at the 2.5 leaf stage of Japanese millet, when weeds have advanced in growth.

The following can be understood from the results in Table 3.

The mixed treatment of compounds [N and [II] and [111-1, -2 or 31] showed a stable and high herbicidal effect on lizardfish, firefly, etc., and the herbicidal effect of the mixture was also significant in field tests. was confirmed.

In particular, it is a mixture that shows long-term herbicidal effects against perennial difficult-to-control weeds such as black bream and Japanese cyperus. The persistence of weed suppression up to the 45th day is notable.

On the other hand, regarding phytotoxicity to paddy rice, although some combinations showed some signs of phytotoxicity, the phytotoxicity was not considered to be a problem in practical terms.

[Effect of the invention 1] The herbicide of the present invention has a synergistic or additive effect between the compound of formula [■1] and the compounds of formula [11] and formula [[II-1, I11-2 and [11-3]]. Depending on the action and effect, it can be used to control annual weeds such as Nobies and Prunus spp.
It is possible to accurately suppress and control perennial difficult-to-control weeds such as black croaker for a long period of time without causing any actual damage to paddy rice with a single treatment, and its usefulness is extremely high compared to commercially available agents.

Claims (2)

[Claims] (1) 2-benzothiazol-2-yloxy-N-methylacetanilide, S-benzyl-N-ethyl-N(
1,2-dimethylpropyl)-thiol carbamate,
one or more compounds from the group consisting of 2,6-diethyl-N-(propoxyethyl)chloroacetanilide;
-(β-naphthoxy)propionanilide and 2,3
- dihydro-3,3-dimethyl-5-benzofuranylethanesulfonate as an active ingredient. (2) The herbicide according to claim 1, which is α-(
2 for 1 part by weight of β-naphthoxy)propionanilide
, 0.05 to 1.0 parts of 3-dihydro-3,3-dimethyl-5-benzofuranylethanesulfonate, and 0.1 to 1.0 parts of 2-benzothiazol-2-yloxy-N-methylacetanilide. , S-benzyl-N-ethyl-
0.2 to 1.5 parts of N(1,2-dimethylpropyl)-thiol carbamate, 0.05 to 0.5 parts of 2,6-diethyl-N-(propoxyethyl)chloroacetanilide
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