JPS638305A - Herbicidal composition - Google Patents

Abstract

PURPOSE:The titled composition, containing a specific carbamate derivative and N-(alpha,alpha-dimethylbenzyl)-2-bromo-3,3-dimethylbutyramide, etc., as an active ingredient, having a wide optimum treatment period of weeds, safe for transplanted paddy rice and capable of sustaining the effect. CONSTITUTION:A herbicidal composition containing (A) one or two or more of carbamate derivatives expressed by the formula (R1 and R2 are H, halogen, lower alkyl or trifluoromethyl; X is O or S), (B) N-(alpha,alpha-dimethylbenzyl)-2- bromo-3,3-dimethylbutyramide and (C) 4-(2,4-dichloro-3-methylbenzoyl)-1,3- dimethyl-5-(4-methylph-enacyloxy)pyrazole. The amounts of the respective components (B) and (C) are preferably 0.1-10pts.wt. based on 1pt.wt. component (A). In use, the amount of the active ingredient is preferably within the range of 10-60g based on 1 are.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a herbicidal composition, in particular a herbicidal composition containing a specific carbamate derivative and N-(α,α-dimethylbenzyl)-2
-bromo-3,3-dimethylbutyramide and 4-
(2,4-dichloro-3-methylbenzoyl)-1,3
-dimethyl-5-(4-methylphenacyloxy)pyrazole as an active ingredient,
The present invention relates to a herbicide composition with excellent herbicidal effects.

[Conventional technology]

Although a large number of herbicides for rice cultivation have already been developed, there is still strong market demand for improved performance, safety, and reduction of chemical damage.

In addition, the characteristics of rice field weeds are that many of them do not occur at the same time and occur over a long period of time, and the growth status of the weeds at the time of herbicide application varies from pre-germination to somewhat advanced growth. There is always a mix of things. For this reason, it is not possible to obtain a satisfactory herbicide effect by spraying the herbicide only once, and the herbicide must be applied several times.

[Problem that the invention seeks to solve]

The present inventors have developed an excellent product that can almost completely control weeds from pre-germination to weeds that have grown to some extent by simply spraying a low dose of the chemical, maintains its effect for a long time, and is highly safe for paddy rice. As a result of intensive research to develop herbicides, we found that one or more specific carbamate derivatives,
N-(α,α-dimethylbenzyl)-2-bromo-3,
3-dimethylbutyramide and 4-(2,4-dichloro-3-methylbenzoyl)-1,3-dimethyl-5
-(4-Methylphenacyloxy)pyrazole in an appropriate ratio, it was discovered that an extremely remarkable synergistic effect that far exceeded expectations could be obtained, and the present invention was completed.

[Means for solving problems]

The herbicidal composition of the present invention comprises one or more specific carbamate derivatives, N-(α,α-dimethylbenzyl)-2-bromo-3,3-dimethylbutyramide and 4-(2, 4-dichloro-3-methylbenzoyl)
-1,3-dimethyl-5-(4-methylphenacyloxy)pyrazole as an active ingredient, it has an excellent herbicidal effect and is highly safe for paddy rice. It has an excellent synergistic effect that cannot be predicted from the herbicidal effect exhibited by either alone.

That is, the present invention provides a carbamate derivative represented by the general formula: (wherein R1 and R2 represent a hydrogen atom, a halogen atom, a lower alkyl group, or a trifluoromethyl group, and X represents an oxygen atom or a sulfur atom) one or more of the following, and N-(α,α-dimethylbenzyl)-2-bromo-3,3-dimethylbutyramide and 4-(2,4-dichloro-3-methylbenzoyl)-1,3 -dimethyl-5-(4-methylphenacyloxy)pyrazole as an active ingredient.

[Effect]

When the specific carbamate derivative represented by the above general formula is used alone as a herbicide for paddy fields, it kills weeds such as grasshopper, cypress, and grasshopper at the pre-emergence stage.

It is highly effective against fireflies, etc., and is also effective against fireflies, etc. The major feature of this drug is that it has a herbicidal effect on weeds, even those that have grown to a certain extent after germination, and there is no practical harm to transplanted paddy rice. . However, the herbicidal effect is not sufficient against some perennial weeds, especially during the weed growing season.

On the other hand, when N-(α,α-dimethylhensyl)-2-bromo-3,3-dimethylbutyramide is used alone as a herbicide for paddy fields, it is effective against fireflies when treated from before to just after weed emergence. It is highly effective against , Japanese cypress, and Japanese cypress, and is also effective against wild grass, Japanese cypress, Japanese cypress, Japanese cyperus, and the like. Furthermore, it is highly safe for paddy rice, and has great utility as a herbicide for paddy fields. However, once the weeds have grown to a certain extent, the weeding effect becomes weaker.

In particular, the weeding effect is insufficient against wild grass during the growing season.

In addition, when 4-(2,4-dichloro-3-methylbenzoyl)-1,3-dimethyl-5-(4-methylphenacyloxy)pyrazole was used alone as a herbicide for rice fields, it It shows high herbicidal effects not only on annual weeds but also on perennial weeds, when treated from to immediately after emergence.

Furthermore, it is also effective against firefly, waterbug, etc. Furthermore, it is highly safe for paddy rice, and has great utility as a herbicide for paddy fields. However, once the weeds have grown to a certain extent, the herbicidal effect becomes weaker, and no weeding effect can be expected, especially against weeds during the growing season.

A specific carbamate derivative represented by the above general formula, and N
-(α,α-dimethylbenzyl)-2-bromo-3,3
-dimethylbutyramide and 4-(2,4-dichloro-3-methylbenzoyl)-1,3-dimethyl-5-(
It was completely unexpected that the herbicide composition of the present invention, which is formulated with 4-methylphenacyloxy) pyrazole, not only compensates for the shortcomings of each drug, but also exhibits an extremely significant synergistic effect. .

There is no particular restriction on the blending ratio of each active ingredient in the herbicidal composition of the present invention, and an excellent synergistic effect can be obtained in a wide range of blending ratios, but it is preferable to add 1 part by weight of the specific carbamate derivative represented by the above general formula. 0.1 to 10 parts by weight of N-(α,α-dimethylbenzyl)-2-bromo-3,3-dimethylbutyramide and 4-(2,4-dichloro-3-methylbenzoyl)-1,3 -dimethyl-5-(
4-Methylphenacyloxy)pyrazole 0.1-1O
Parts by weight are appropriate.

When the herbicidal composition of the present invention is actually used, one or more specific carbamate derivatives represented by the above general formula and N-(α,α-tumethylbenzyl)-2
-bromo-3,3-dimethylbutyramide and 4-
(2,4-dichloro-3-methylbenzoyl)-1,3
-Dimethyl-5-(4-methylphenacyloxy)pyrazole in appropriate amounts are mixed with an inert carrier to form granules, fine granules, permanent agents, emulsions, which are commonly used forms of agricultural chemicals.
It can be used in various forms such as powders and flowables.

As solid carriers, calcium carbonate, apatite.

Gypsum, silica gel, vermiculite, mica.

Diatomaceous earth, talc 2 pyroferrite, acid clay, clay, kaolinite, montmorolinite.

Examples include mineral powders such as bentonite and white carbon 2 pumice powder, vegetable powders such as crystalline cellulose and starch, and polymeric compounds such as polyvinyl chloride and petroleum resins.

Liquid carriers include methanol and ethanol.

Alcohols such as cyclohexanol, amyl alcohol and ethylene glycol; aromatic hydrocarbons such as benzene, toluene, xylene and methylnaphthalene; ketones such as isophorone and cyclohexanone; chlorobenzene;
Examples include halogenated hydrocarbons such as trichloroethylene, ethers such as ethyl cellosolve, butyl cellosolve, and dioxane, esters such as isopropyl acetate and benzyl acetate, polar solvents such as dimethylformamide and dimethyl sulfoxide, kerosene, mineral oil, and water. Can be done.

In addition, surfactants and spreading agents may be added if necessary for the formulation.

The reliability of the herbicidal effect can be increased by adding adjuvants used in agricultural chemicals such as binders or stabilizers.

In addition, the herbicide composition of the present invention may optionally contain an insecticide,
It may also contain or be used in combination with pesticides, plant growth regulators, fertilizers, or other herbicides.

The amount of each active ingredient when preparing the herbicide composition of the present invention depends on the application situation, application time, and application method.

Although it varies depending on the target grass species, etc., the amount of the specific carbamate derivative represented by the above general formula is generally 1 to 50 g, preferably 2 to 30 g, in terms of the amount of active ingredient per are, and N-(α, α-dimethylhensyl)-2-bromo3
．． 3-dimethylbutyramide is generally 1 to 50g1
Preferably it is 2 to 30 g, and 4-(2,4-dichloro-3-methylbenzoyl)-1,3-dimethyl-5-(
The amount of 4-methylphenacyloxy)pyrazole is generally 1 to 50 g, preferably 2 to 30 g.

In addition, the total amount of active ingredients is generally 5 to 1 per are.
00g, preferably in the range of 10 to 60g.

The content of the total active ingredients in the preparation is suitably in the range of 1 to 90%, preferably 3 to 80% in terms of weight ratio.

Specific examples of the carbamate derivative represented by the above general formula, which is one of the active ingredients according to the present invention, are shown below. It goes without saying that the specific carbamate derivatives according to the present invention are not limited to the compounds of this specific example.

This compound name is cited in the description below.

Compound class Compound name 1, 0-4-tert-butylphenyl N-(
6-medoxy2-pyridyl)-N=methylthiocarbamate 2, 0-3-tert-butylphenyl N-(
6-medoxy2-pyridyl)-N-methylthiocarbamate 3, 0-4-trifluoromethylphenyl N-(
6-medoxy2-pyridyl)-N-methylthiocarbamate 4, 0-4-bromo-3-methylphenyl N-(
6-Medoxy 2-pyridyl)-N-methylthiocarbamate 5, 3-tert-butyl-4-chlorophenyl N-(6-medoxy 2-pyridyl)-N-methylcarbamate 6, 0-4-chloro-3-ethylphenyl N-(
6-Medoxy (2-pyridyl)-N-methylthiocarbamate [Example] Next, an example of the formulation of the herbicide composition of the present invention will be described.
The present invention is not limited to these. In the examples, "parts" indicate parts by weight.

Example 1 4.10 parts of compound, N(α,α-dimethylbenzyl)
10 parts of -2-bromo-3,3-dimethylbutyramide and 15 parts of 4-(2,4-dichloro-3-methylbenzoyl)-1,3-dimethyl-5-(4-methylphenacyloxy)pyrazole. The mixture was mixed and pulverized with 61 parts of Diatomium, 2 parts of Neoperenx (trade name: manufactured by Kao Atlas ■) and 2 parts of Tsurupol 800A (trade name: manufactured by Toho Chemical Industry ■) to obtain a wettable powder.

Example 2 1.5 parts of the compound, N-(α,α-dimethylbenzyl)
5 parts of -2-bromo-3,3-dimethylbutyramide and 4-(2,4-dichloro-3-methylbenzoyl)-
An emulsion was obtained by mixing and dissolving 7 parts of 1,3-dimethyl-5-(4-methylphenacyloxy)pyrazole with 10 parts of Trupol 800A and 73 parts of xylene.

Example 3 Compound 1.4 parts, N-(α,α-dimethylbenzyl)
5 parts of -2-bromo-3,3-dimethylbutyramide and 4-(2,4-dichloro-3-methylbenzoyl)-
5 parts of 1,3-dimethyl-5-(4-methylphenacyloxy)pyrazole, 35 parts of bentonite, 48 parts of talc
After mixing and pulverizing 1 part and 3 parts of Tsurupol 800A,
The mixture was kneaded with an appropriate amount of water, extruded through a sieve hole with a diameter of 0.71 mm, dried, and then cut into lengths of 1 to 21 mm to obtain granules.

Next, the excellent herbicidal effect of the herbicide composition of the present invention will be explained using Examples and Comparative Examples.

Example 4 and Comparative Examples Paddy soil that had been made into a paddy field by adding water was put into a plastic container with a diameter of 21 cm, seeds of various weeds were sown on the surface layer of the soil, and the germinated tubers of Cyperus japonica and Urikawa were transplanted. Two Hazuki paddy rice seedlings (variety: Nipponbare) were planted at a depth of ICIm. After that, it was flooded with water for 20 minutes and left in a greenhouse. Three days after transplanting paddy rice (prior to germination of Novieum) and 10 days after transplanting paddy rice (Two-leaf Novie stage), a predetermined amount of granules of the herbicide composition of the present invention prepared according to the method shown in Example 3 above, Sprayed by hand. The plants were then placed in a greenhouse and watered at appropriate times. 3 weeks after treatment with ti agent,
The herbicidal effect and chemical damage to paddy rice were investigated. Table 1 shows the results of the treatment 3 days after rice transplantation, and Table 2 shows the results of the treatment 10 days after rice transplantation.

In addition, in Tables 1 and 2, "active ingredient A" refers to a specific carbamate derivative represented by the above general formula, and "active ingredient B" refers to N-(α,α-dimethylbenzyl). 4-(2,4-dichloro-
3-methylbenzoyl)-1,3-dimethyl-5-(4
-methylphenacyloxy)pyrazole, and
The "drug amount" in each table indicates the amount of active ingredient converted to the amount per 1 are of paddy field.

Evaluation of herbicidal effect and phytotoxicity was made according to the following criteria.

Weeding effect judgment criteria Chemical damage judgment criteria 10:100
% control - 2 no Harm 9: 90% control
Master: Minor harm 8: 80% control +: Minor harm 7
: 70% control +: Medium Harm 6: 60% control +1 + two major Harm 5: 50% control
×: Blight 4: 40% control 3: 30% control 2: 20% control 1: 10% control 0: 0% control As a comparative example, each active ingredient compound was used alone or in combination in the same manner as in the above example. Evaluations of herbicidal effects and phytotoxicity in treated and untreated plots were also conducted according to the above criteria and are shown in the table below.

The excellent synergistic effect of each active compound brought about by the present invention is already clear from the results of Example 4, but it will be explained in more detail using Cyperus japonica, which is one of the difficult-to-control weeds, as a representative grass species. .

As a method for assaying the interaction of three active compounds, Colby's calculation formula described in Weeds 15S, pages 20-22, 1967, is usually used.

That is, however, X = herbicidal effect (X) when compound A is used in pg/a Y =
Herbicidal effect (χ) when compound B is used at Q g/a Z = Herbicidal effect (χ) when compound C is used at r g/a E = A,
Expected herbicidal effect (X) when B and C are mixed in p, q, and rg/a, respectively. If the actually measured herbicidal effect (%) exceeds E, the composition has a synergistic effect. It shows that it exists.

EXAMPLES Hereinafter, the interaction test of the herbicide composition of the present invention and its results will be shown in Examples.

Example 5 Paddy soil in a paddy field was poured into a plastic container with an area of 1836 c+J (31 x 56 (J)) to a depth of 7 cm from the bottom, and 10 tubers of Cyperus japonica were transplanted into the container.

The next day, the plants were flooded with 3 cm of water and grown in a greenhouse. transplant 7
After a day, a predetermined amount of the herbicidal composition of the present invention prepared according to Example 3 and granules of each active ingredient compound alone were sprayed by hand. The plants were then placed in a greenhouse and watered at appropriate times.

Thirty days after the chemical treatment, the remaining stems and leaves of Cypera were cut and collected, air-dried samples were measured, and the herbicidal effect was calculated using the following formula, and the results are shown in Table 3.

Herbicidal effect (χ) (air-dried type in untreated area) Table 3 [Effects of the invention] As is clear from Tables 1, 2, and 3, the herbicidal composition of the present invention has various effective The herbicidal power is significantly enhanced compared to when each component is applied alone. This is due to the synergistic effect between each active ingredient, and it is recognized that there is a significant synergistic effect.

In other words, the greatest feature of the herbicide composition of the present invention is that a high herbicidal effect on many weeds can be obtained by combining low dosages that could not be expected from the herbicidal effect of each active ingredient alone. I can list things that I can do.

In addition, the herbicide composition of the present invention exhibits remarkable herbicidal activity not only against weeds at the early stage of growth but also against weeds at a certain stage of advanced growth. One of its excellent features is that it has a wide range of suitable processing periods.

In addition, there are many types of weeds that can be controlled, and a remarkable herbicidal effect has been observed on annual weeds such as Japanese wild grass, Japanese cypress, Japanese cypress, and perennial weeds such as Japanese firefly, Japanese cypress, and Japanese snail. Moreover, it does not cause any chemical damage to transplanted paddy rice, making it highly useful as a highly safe and highly selective herbicide. Because the active ingredient has a long residual effect, it exhibits high herbicidal activity over a long period of time and can control many weeds.
It greatly contributes to the reduction of spraying labor, that is, the labor saving of agricultural work.

As described above, the herbicidal composition of the present invention has many excellent features and is highly practical.

Claims (1)

[Claims] General formula: ▲Mathematical formula, chemical formula, table, etc.▼ (In the formula, R_1 and R_2 represent a hydrogen atom, a halogen atom, a lower alkyl group, or a trifluoromethyl group,
X represents an oxygen atom or a sulfur atom. ) and one or more carbamate derivatives represented by N-(α,α
-dimethylbenzyl)-2-bromo-3,3-dimethylbutyramide and 4-(2,4-dichloro-3-methylbenzoyl)-1,3-dimethyl-5-(4-methylphenacyloxy)pyrazole. A herbicide composition containing as an active ingredient.