JPH0381208A - Herbicide composition for rice field - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a herbicidal composition, and more particularly to a herbicidal composition containing a combination of three types of compounds with different herbicidal mechanisms and herbicidal spectra as active ingredients. The present invention relates to a herbicide composition for paddy fields that has a herbicidal spectrum and exhibits sufficient herbicidal effects at low doses.

[Conventional technology]

Up to now, many herbicides have been put into practical use for paddy fields, and they have been widely used as single agents or mixtures containing two or more types of herbicides.

However, although these agents are relatively effective against annual weeds, they are insufficiently effective against perennial weeds.
Therefore, in recent years, perennial weeds such as firefly and weed have been increasing in rice fields in Japan. These perennial weeds are extremely difficult to control because they are numerous in variety, prolific, and last for a long period of time. Although herbicides have been repeatedly sprayed for control, the current situation is that sufficient effects have not been obtained.

In addition, recently, various herbicides called one-shot herbicides, which aim to achieve the purpose of weeding with a single treatment, have been put into practical use one after another, but these are also insufficiently effective against perennial weeds. For these reasons, farmers are eagerly awaiting the development of new herbicides that can compensate for these shortcomings, such as the fact that they are not fully effective unless used very soon after rice planting.

[Problem to be solved by the invention]

The present inventors conducted various studies in order to develop a herbicide for rice fields that satisfies the above-mentioned demands of farmers.

As a result, three types of compounds with different herbicidal mechanisms and herbicidal spectra were identified: known thiol carbamate herbicides, known sulfonylurea herbicides, and known triazine herbicides. , preferably in combination in a specific ratio, can selectively control a wide range of weeds in rice fields, and their herbicidal efficacy increases synergistically compared to when they are used alone,
Therefore, it was discovered that the herbicidal composition of the present invention can be applied at a low dose and the herbicidal spectrum is further expanded, leading to the completion of the herbicidal composition of the present invention.

[Means to solve the problem]

According to the invention, (a) Formula (I) 0 CH.

5-(1-methyl-1-phenylethyl)piperidine-1-carbothioate (hereinafter sometimes referred to as "compound (I)") and (b) represented by formula (■): Methyl-2-[([(((4,6-cymethoxypyrimidin-2-yl)amino]carbonyl]amino]sulfonyl]methyl]benzoate (hereinafter sometimes referred to as "compound (■)") and (C) Formula (■): In the formula, both R1 and R2 represent an alkyl group, and a 2-methylthio-1,3,5-) riazine derivative (hereinafter referred to as "compound (■)") There is provided a herbicidal composition for paddy fields, characterized in that it contains any one of three components selected from the following as active ingredients.

The composition of the present invention comprises the formula (I), formula (II) and formula (
By using the three active ingredients shown in III) with different herbicidal mechanisms and herbicidal spectra in combination, preferably in a specific ratio, a much smaller dosage can be obtained than when each is used alone. This makes it possible to expand the herbicidal spectrum and the period of use, making it an excellent herbicide for paddy fields that exhibits a strong synergistic effect when used in combination with the three types of compounds mentioned above.

Thus, according to the present invention, a sufficient control effect is exerted on difficult-to-control perennial weeds that occur in rice fields, the range of suitable treatment periods is expanded, and the application does not cause chemical damage to paddy rice, while still providing the necessary activity for weed control. It is also possible to reduce the amount of ingredients, and an agriculturally useful herbicide can be provided.

Hereinafter, the herbicidal composition of the present invention will be explained in more detail.

The above formula (I) used in the herbicidal composition of the present invention
5-(1-methyl-1-phenylethyl)piperidine-1-carbothioate and its use as a herbicide are known (see Japanese Patent Publication No. 36167/1983). This compound belongs to thiol carbamate herbicides and has protein and lipid synthesis inhibiting effects as its main function, and although it exhibits an excellent herbicidal effect on grasshoppers, it is less effective against other weeds.

Furthermore, methyl-2-([[:((4,6-cymethoxypyrimidin-2-yl]amino]carbonyl]amino]sulfonyl) of the formula (n) used in the herbicidal composition of the present invention Methyl]benzoate and its use as a herbicide are known (see Japanese Patent Publication No. 62-6705 Bonho). This compound belongs to the sulfonylurea herbicides,
Its main mechanism of action is to inhibit branched amino acid synthesis, and although it has excellent herbicidal effects against a wide range of weeds,
It has almost no effect on wild grass, which is an important weed in rice fields.

Furthermore, the 2-methylthio-1,3,5-triazine derivative of the general formula (III) used in the herbicidal composition of the present invention and its use as a herbicide are known [Pesticide Manual (The Pe5tic
ide Manual) 8th edition 1987 (TheBr
(Published by Crop Council 1), British Patent No. 1.191.585, Swiss Patent P 337.
019, US Pat. No. 2.909.420, etc.].

2-methylthio-1,3,5- of the general formula (III)
Among the triazine derivatives, the following compounds are particularly preferably used: 2-methylthio-4-(l,2-dimethylpropylamino)-6-nitylamino-1,3.5-)riazine (hereinafter referred to as "compound (I)") [Sometimes called [-1)J]
, 2-methylthio-4,6-bis(ethylamino)-1,
3,5-) riazine (hereinafter referred to as "compound (In-2)")
), 2-methylthio-4,6-bis(isopropylamino')
) -1,3,5-)! J azine (hereinafter sometimes referred to as "compound (I[r-3)J").

These compounds lll-1, m-2 and lll-3 are
British Patent No. 1.191.585, Swiss Patent No. P 337.019 and US Patent No. 2.909.
It is a known compound disclosed in Japanese Patent No. 420, and its use as a herbicide is also known.

The compound represented by the general formula (III) belongs to triazine herbicides and has a photosynthesis inhibiting effect as its main mechanism of action. Although the control effect is excellent, the effect against other weeds is low.

Furthermore, it is also known to use a combination of the compounds represented by formula (I) and formula (II) as a herbicide for paddy fields (see JP-A-59-82307).

The herbicidal composition of the present invention containing the above-mentioned active ingredients exhibits a strong synergistic effect in a wide range of mixing ratios. Three preferred active ingredients [Compound (L), Compound (■), Compound (
The mixing ratio of compound (n) to 1 part by weight of compound (I) is usually 0.001 to 1 part by weight of compound (II).
I) is 0.001 to 10 parts by weight, particularly preferably 0.005 parts by weight of compound (II) per 1 part by weight of compound (I)
~0.6 parts by weight, 0.01 to 0.1 of compound (III)
It can be parts by weight.

When the composition of the present invention is actually used as a herbicide, it is mixed with known solid or liquid carriers, surfactants, and other formulation auxiliaries in a manner known per se.
It can be formulated into formulations commonly used as agricultural chemicals, such as granules, emulsions, wettable powders, and flowables.

Solid carriers used in the formulation include clays and talc represented by the kaolinite group, senmolinite group, or abatalgite group; mica, waxite, pumice, acid clay, vermiculite, bentonite, gypsum, calcium carbonate, dolomite, Inorganic substances such as diatomaceous earth, magnesium lime, apatite, zeolite, anhydrous silicic acid, and basal calcium silicate; coumaron resin, petroleum resin, alkyd resin, polyvinyl chloride, polyalkylene glycol, ketone resin, ester gum, Synthetic or natural polymer compounds such as copal gum and dammar gum: carnauba wax,
Examples include waxes such as beeswax; urea, plant organic substances, etc.

Suitable liquid carriers include, for example, paraffinic or naphthenic hydrocarbons such as kerosene, mineral oil, spindle oil, white oil; aromatic hydrocarbons such as benzene, toluene, xylene ethylbenzene, cumene, methylnaphthalene; carbon tetrachloride; Chloroform, trichlorethylene,
Chlorinated hydrocarbons such as monochlorobenzene and orthochlorotoluene; Ethers such as dioxane and tetrahydrofuran; Ketones such as acetone, methyl ethyl ketone, diisobutyl ketone, cyclohexanol, and isophorone; ethyl acetate, amyl acetate, ethylene glycol acetate, Esters such as diethylene glycol acetate, dibutyl maleate, diethyl succinate; alcohols such as methanol, n-hexanol, ethylene glycol, diethylene glycol, cyclohexanol, benzyl alcohol; ethylene glycol ethyl ether, ethylene glycol phenyl ether, diethylene glycol ethyl ether, Examples include ether alcohols such as diethylene glycol butyl ether, polar solvents such as dimethoxyformamide and dimethyl sulfoxide, and water.

In addition, surfactants and other auxiliary agents may be used for the purpose of emulsifying, dispersing, wetting, spreading, binding, adjusting disintegrability, stabilizing the active ingredient, improving fluidity, preventing rust, preventing freezing, etc. of the active ingredient. You can also do it.

Examples of surfactants that can be used include nonionic, anionic, cationic and zwitterionic compounds, but usually nonionic and/or anionic compounds are used. used.

Suitable nonionic surfactants include, for example, compounds in which ethylene oxide is polymerized and added to higher alcohols such as lauryl alcohol, stearin alcohol, and oleyl alcohol; compounds in which ethylene oxide is polymerized and added to alkyl phenols such as isooctylphenol and nonylphenol; Compounds in which ethylene oxide is polymerized and added to alkylnaphthols such as butylnaphthol and octylnaphthol; Compounds in which ethylene oxide is polymerized and added to higher fatty acids such as valmitic acid, stearic acid, and oleic acid; Higher fatty acid esters of polyhydric alcohols such as sorbitan; In addition, compounds obtained by block polymerization addition of ethylene oxide and propylene oxide are included.

Suitable anionic surfactants include, for example, alkyl sulfate salts such as sodium lauryl sulfate and oleyl alcohol sulfate amine salt; alkyl sulfonate salts such as sodium sulfosuccinate dioctyl ester and sodium 2-ethylhexene sulfonate; Examples include aryl sulfonates such as sodium isopropylnaphthalene sulfonate, sodium methylene bisnaphthalene sulfonate, sodium lignin sulfonate, and sodium dodecylbenzenesulfonate.

Furthermore, the composition of the present invention contains casein, gelatin, albumin,
Polymer compounds such as glue, sodium alginate, carboxymethyl cellulose, polyvinyl alcohol, and other auxiliary agents can also be used in combination.

The above-mentioned carriers and various auxiliary agents are used alone or in combination as appropriate depending on the purpose, taking into account the dosage form of the preparation, the place of application, etc.

The content of the active ingredient in the composition of the present invention in various preparations thus obtained varies depending on the formulation, but is usually 0.1 to 99% by weight, preferably 1 to 80% by weight.
'% by weight.

In the case of granules, for example, the active ingredient compound is usually contained in an amount of 1 to 35% by weight, and the remainder is a solid carrier, a surfactant, and the like.

Is the active ingredient compound homogeneously mixed with the solid carrier?
Alternatively, it is uniformly fixed or adsorbed on the surface of a solid carrier, and the particle size is about 0.2 to 1.5 m.

In the case of hydrating agents, for example, the active ingredient compound is usually 25 to 9
The remaining amount is a solid carrier and a dispersion wetting agent, and a protective colloid agent, an antifoaming agent, etc. are added as necessary.

In the case of flowable agents, for example, the active ingredient compound is usually
~50% by weight, in addition to 3 to 10% by weight
The remainder is water, and a protective colloid, a preservative, an antifoaming agent, etc. are added as necessary.

The appropriate application amount of the composition of the present invention formulated as described above varies depending on weather conditions, soil conditions, drug formulation, application period, application method, type of weed, and density of weeds, etc., but cannot be unconditionally defined. The total amount of active ingredients per lha is 0
, 12-11.1 kg, preferably 1.56-3.7
kg. When applying to paddy fields, emulsions, wettable powders, flowables, etc. are usually applied without diluting the prescribed amount or after diluting with an appropriate amount of water, and granules, etc. are usually applied as is without any dilution. do. Preferably, the formulation is in the form of granules, and it is easiest and most effective to disperse using a rotary granulator, a power granulator, etc.

Furthermore, the composition of the present invention can be formulated into a labor-saving herbicide by appropriately blending other herbicides, insecticides, fungicides, plant growth regulators, etc.

Furthermore, it is also possible to mix and use various agricultural chemicals, such as insecticides, fungicides, plant growth regulators, herbicides, fertilizers, etc., at the time of spraying, if necessary.

The present invention will be explained in detail below using Examples, but the blending ratio, dosage form, etc. of the composition of the present invention are not limited to the Examples. Note that "parts" used in the following implementation are based on weight.

Example (1) Production of granules 1 Compound (1) 8.00 parts Compound (n) 0.17 parts Compound (III-1) 0.5
0 parts bentonite 35.00
Part clay 52.3a Part Sodium dodecylbenzenesulfonate 2.0ON Sodium ligninsulfonate After mixing and pulverizing 2.0OfB or more to make it homogeneous, add an appropriate amount of water and knead well, then granulate using a granulator. The mixture was granulated and then subjected to a drying process to obtain 100 parts of granules.

(2) Production of granules 2 Compound (I) 8.00
Part compound (IF) 0.1
7-part compound (III-2>0
．． 50 parts bentonite 35.
00 parts clay 52.3
3 parts Sodium dodecylbenzenesulfonate 2.00 parts Sodium ligninsulfonate 2.00 parts or more are mixed and ground to make it homogeneous, then an appropriate amount of water is added, kneaded well, and then granulated using a granulator. Further, 100 parts of granules were obtained through a drying process.

(3) Production of Granule 3 Compound (1) Compound (n) Compound (III-3) Bentonite clay 8.00 parts 0.17 parts 0.50 parts 35.00 parts 52.33 parts Sodium dodecylbenzenesulfonate 2 .00 parts Sodium ligninsulfonate After mixing and pulverizing 2.00 parts or more to make it homogeneous, add an appropriate amount of water and knead well, then granulate using a granulator, and then go through a drying process to form granules. Got 100 copies.

〔Effect of the invention〕

The above-mentioned active ingredient compounds used in the herbicidal composition of the present invention are each known and widely used herbicides. However, as mentioned above, when each of these herbicides is used alone, the types of weeds that can be controlled are limited and the effectiveness is not sufficient.

As mentioned above, the herbicide composition of the present invention is characterized by having a combination of three types of active ingredient compounds with different mechanisms of action and action spectra, and it is difficult to control the herbicide using each active ingredient compound alone. Not only do they complement each other, but they also exhibit excellent herbicidal effects against common weeds at low dosages that cannot be used alone.

For example, the herbicidal composition of the present invention can be used to control long-lived weeds that occur in rice fields, such as grasshopper, grasshopper, broad-leafed grass, and cyperus; It is possible to effectively control perennial weeds such as Japanese parsley, Ezonosa japonica, and Kusanem. On the other hand, it is extremely safe for crops and does not cause any chemical damage to paddy rice.

Furthermore, the herbicide composition of the present invention can be used at any time within a wide period from after transplanting paddy rice to the peak of weed growth. The specific timing of application can be arbitrarily selected from a wide range from before rice transplantation to the peak of weed growth (approximately 15 days after transplantation), but it is most effective if treated at the early stage of weed emergence (up to about 7 days after transplantation). A high weeding effect can be obtained.

Furthermore, the herbicidal composition of the present invention has a long-lasting herbicidal effect and substantially does not allow weeds to emerge until the rice harvest period.

These excellent effects clearly suggest the existence of a strong synergistic effect between the respective active ingredients contained in the herbicidal composition of the present invention, which could not be predicted from the herbicidal properties of each of them alone. This shows the effect that is not possible.

In addition, the herbicide composition of the present invention has a high herbicidal power of each active ingredient alone, and also has a strong synergistic effect.
Compared to conventional herbicides, the amount of effective dosage required is extremely small. Therefore, it can be said to be a herbicide that is highly safe for the environment and farmers, and meets the needs of the times.

Next, the effects of the herbicide composition of the present invention will be explained by giving a trial example.

Test example 1 (Drug dose reduction effect by mixing) Area 1/200
Put paddy soil and chemical fertilizer in a 0a Wagner pot,
Add an appropriate amount of water and stir thoroughly to form a paddy field.

Add 2 paddy rice seedlings at the 2-leaf stage that were grown in a greenhouse in advance.
Transplant 2 plants per pot as stocks, and use
Seeds of azalea and bulrushes, and tubers of urikawa and cypress were sown in fixed amounts. Seven days after transplantation, a predetermined amount of the test compound was treated using granules (prepared according to the examples). 30 days after the chemical treatment, the herbicidal effect and the degree of chemical damage to paddy rice were investigated. The results are shown in Tables 1-1, 1-2, and 1-3. In addition, the herbicidal effect on each grass species and the degree of paddy rice damage in the table are as shown in the table below for the herbicidal effect and the degree of paddy rice damage, respectively, with a six-level rating from "O" to "5".
and is represented by a six-level code from "-" to rXJ.

Herbicidal effect 00 More than 80 and less than 100 More than 60 and less than 80 More than 40 and less than 60 More than 20 and less than 40 0 and less than 20 It has been found that the herbicidal composition can control weeds that are hard to control, such as common weeds and weeds such as fireweed, meadow grass, and cypress, with an extremely lower dose than when each active ingredient is used alone.

Test Example 2 (Effect of extending the period of use by mixing) The test plant was only wild grass, and a pot prepared in the same manner as Test Example 1 was treated with granules formulated according to the example over time. Fifty days after the pot preparation, the herbicidal effect was determined using the same criteria as in Test Example 1.

The results are shown in Table 2-1, Table 2-2, and Table 2-3.

From the results in Table 2-1, Table 2-2, and Table 2-3, it is clear that in each of the herbicide compositions of the present invention, each active ingredient acts synergistically to significantly extend the weeding period. was confirmed.

Test Example 3 (Field Test) A paddy field that had been planted according to normal farming methods was partitioned using ridge sheets (Shin-Etsu Chemical Department; trade name: "Azenami") so that each section was 10 m" (4 m x 2.5 m). Each drug (granule) was treated on the 7th day after rice planting.
Usual management was carried out, and the herbicidal effect and paddy rice damage were judged using the same criteria as in Test Example 1 40 days after the chemical treatment.

The results are shown in Table 3-1, Table 3-2, and Table 3-3. It should be noted that all weeds occurred naturally, except for the sowing of wild grass seeds.

Table 3-1 Table-2 Table-3 As shown by the results of Test Examples 1 to 3 above, the herbicide composition of the present invention has a wide treatment period after rice planting and can effectively control various weeds. It is extremely promising as a highly safe herbicide for paddy fields.

Claims (1)

[Claims] (1) (a) Formula (I): ▲Mathematical formulas, chemical formulas, tables, etc.▼S-(1-methyl-1-phenylethyl)piperidine-1-carbothioate represented by (I) and (b ) Formula (II): ▲There are mathematical formulas, chemical formulas, tables, etc.▼(II) Methyl-2-[[[[[[[4,6-dimethoxypyrimidin-2-yl]amino]carbonyl]amino] Sulfonyl]methyl]benzoate (c) formula (III)
: ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (III) In the formula, R^1 and R^2 both represent an alkyl group, selected from 2-methylthio-1,3,5-triazine derivatives represented by A herbicide composition for rice fields, characterized by containing any one of three components as active ingredients.