JP2021075464A - Herbicide composition - Google Patents

Abstract

To provide a new agent made from natural components having excellent control effect on weeds.SOLUTION: A herbicide composition contains a first fatty acid salt and a second fatty acid salt, selected from C2-10 fatty acid salts, where, the first fatty acid salt and second fatty acid salt are formed of different types of bases.SELECTED DRAWING: None

Description

The present invention relates to a herbicide composition. More specifically, the present invention relates to a herbicide composition containing two kinds of fatty acid salts as active ingredients.

In recent years, the need for herbicides derived from natural products has increased due to the improvement of users' safety consciousness.
As a proposal for this need, plant growth regulation that utilizes the effect that chemical substances released from plants have an inhibitory or promoting effect on other plants and promotes / inhibits plant growth (allelopathy effect). There are agents (for example, Patent Documents 1, 2, etc.). However, due to reasons such as difficulty in obtaining active ingredients, it has not yet become widespread.
In addition, it is known that fatty acids, which are natural products that are also present in animals and plants, are compounds having herbicidal activity, and there is a track record that drugs containing nonanoic acid as an active ingredient have been sold as pesticides. However, these herbicidal fatty acids have contact-type action characteristics that cause a mortality reaction only at the contact site, and have low osmotic transferability in the plant body, so that they adhere to the above-ground part when treated. Sufficient effect cannot be obtained on insufficient parts such as roots and seeds in the ground. Therefore, a satisfactory herbicidal effect has not been obtained, such as regeneration from a site where adhesion is insufficient and unwanted plant germination being observed on the ground surface immediately after application. Furthermore, since these fatty acids having herbicidal activity are a group of compounds having a unique odor, there is also a problem of odor at the time of application.
Under these circumstances, the development of a new drug derived from a natural ingredient, which has an excellent control effect on weeds, has been desired.

Japanese Unexamined Patent Publication No. 2006-089400 JP-A-2009-274970

An object of the present invention is to provide a new agent derived from a natural ingredient, which has an excellent control effect on weeds.

As a result of intensive studies to solve the above problems, the present inventor has found that the combination of two specific fatty acid salts has a high germination inhibitory effect on underground seeds, and the present invention has been found. Has been completed.
Conventionally, fatty acids or salts thereof have contact-type action characteristics that cause a mortality reaction only at the contact site, and have low osmotic transferability in plants, so that adhesion is insufficient when treated on the above-ground part. It has been known that a sufficient effect cannot be obtained on the part of the plant, for example, the root or seed in the ground. However, it has been newly found that a control effect is exhibited on seeds in the ground by using two kinds of specific fatty acid salts in combination, and the above-mentioned problems have been solved.

The gist of the present invention is as follows.
1. 1. In a herbicide composition containing a first fatty acid salt and a second fatty acid salt selected from fatty acid salts having 2 to 10 carbon atoms.
A herbicide composition comprising different types of bases forming the first fatty acid salt and the second fatty acid salt.
2. 1. The first fatty acid salt and the second fatty acid salt are the same fatty acid. The herbicide composition according to.
3. 3. 1. The first fatty acid salt is a fatty acid potassium salt. Or 2. The herbicide composition according to.
4. The first fatty acid salt is a fatty acid potassium salt, and the second fatty acid salt is a fatty acid ammonium salt. ~ 3. The herbicide composition according to any one of the above.
5. A synergistic and long-term weed control method, which comprises using a herbicide composition containing a first fatty acid salt and a second fatty acid salt, which is selected from fatty acid salts having 2 to 10 carbon atoms.

According to the present invention, each of the two specific fatty acid salts has a contact-type herbicidal activity independently, so that in addition to exerting an excellent control effect on weeds growing on the ground surface, two specific types of specific fatty acid salts Due to the combined effect of the fatty acid salt, an excellent germination suppressing effect is exerted on the seeds existing in the ground, so that an excellent herbicidal effect can be obtained for a long period of time.

Hereinafter, the present invention will be described in detail.
<About fatty acid salts with 2 to 10 carbon atoms>
The fatty acids having 2 to 10 carbon atoms in the present invention include saturated fatty acids and unsaturated fatty acids. Among them, saturated fatty acids are preferable, and specific examples thereof include acetic acid, propionic acid, butanoic acid, pentanic acid, hexanoic acid, heptanic acid, octanoic acid, nonanoic acid, and decanoic acid. Of these, acetic acid, octanoic acid, nonanoic acid, and decanoic acid are preferable.
Examples of these fatty acid salts include sodium salt, potassium salt, calcium salt, magnesium salt, ethanolamine salt, triethanolamine salt, ammonium salt and the like.

<About the first fatty acid salt and the second fatty acid salt>
The herbicide composition of the present invention contains a first fatty acid salt and a second fatty acid salt selected from fatty acid salts having 2 to 10 carbon atoms.
The fatty acid constituting the first fatty acid salt and the fatty acid constituting the second fatty acid salt may be the same fatty acid or different fatty acids, but the base forming the first fatty acid salt and The bases forming the second fatty acid salt must be of different types. For example, when the first fatty acid salt is a fatty acid potassium salt, the second fatty acid salt is a combination of a fatty acid sodium salt or a fatty acid ammonium salt other than the fatty acid potassium salt as an active ingredient of the herbicide composition of the present invention. Become.
As the first fatty acid salt in the herbicide composition of the present invention, a fatty acid sodium salt, a fatty acid potassium salt or a fatty acid ammonium salt is preferable, and among them, the fatty acid potassium salt is more preferable.
When the first fatty acid salt in the herbicide composition of the present invention is a fatty acid potassium salt, the second fatty acid salt is preferably a fatty acid ammonium salt from the viewpoint of quick-acting property and solubility.
In the herbicide composition of the present invention, the first fatty acid salt and the second fatty acid salt may be prepared separately, or the fatty acid to be used and the two types of bases may be added separately. Salts may be formed in the formulation. In particular, when the same fatty acid is used as the fatty acid constituting the first and second fatty acid salts, the fatty acid to be used and two kinds of bases are mixed, and the first fatty acid salt and the second fatty acid are mixed in the preparation. It is convenient and preferable to form a fatty acid salt to obtain the herbicide composition of the present invention.

The herbicide composition of the present invention preferably contains the first fatty acid salt and the second fatty acid salt in total at 0.1% by weight or more and 20% by weight or less of the entire herbicide composition at the time of application. Above all, it is more preferable to contain 0.1% by weight or more and 18% by weight or less, and further preferably 0.1% by weight or more and 15% by weight or less.
In the herbicide composition of the present invention, the weight ratio of the first fatty acid salt to the second fatty acid salt is 1: 1 to 1: 100 as the weight ratio of the base blended with the fatty acid having 2 to 10 carbon atoms. It is preferably within the range, more preferably the range of 1: 1 to 1:80, and even more preferably the range of 1: 1 to 1:50.

The herbicide composition of the present invention contains the first fatty acid salt and the second fatty acid salt of the present invention, and can be used as various preparations.
Examples of the preparation include oils, emulsions, wettable powders, flowables (suspensions in water, emulsions in water, etc.), microcapsules, powders, granules, tablets, liquids, sprays, aerosols, etc. Be done. Among these, a spray formulation such as a spray agent or an aerosol agent, a spray agent in which a liquid agent is filled in a container with a watering can head, or the like is suitable as the formulation of the herbicide composition of the present invention.
As one production example of the above-mentioned preparation, a solution (Liquid A) is prepared by dissolving the first fatty acid salt and the second fatty acid salt of the present invention in a solvent using a surfactant if necessary. A method of preparing a herbicide composition that does not need to be diluted at the time of use can be mentioned by mixing the solution A with an appropriate amount of water and stirring the mixture to form a preparation.
As the water, tap water, ion-exchanged water, distilled water, filtered water, sterilized water, groundwater and the like can be used.

Examples of the liquid carrier used in the preparation include alcohols (methanol, ethanol, isopropyl alcohol, butanol, hexanol, benzyl alcohol, ethylene glycol, etc.) and ethers (diethyl ether, ethylene glycol dimethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl). Ether, propylene glycol monomethyl ether, tetrahydrofuran, dioxane, etc.), esters (ethyl acetate, butyl acetate, isopropyl myristate, ethyl lactate, etc.), ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), aromatic or fat Group hydrocarbons (xylene, toluene, alkylnaphthalene, phenylxysilyl ethane, kerosine, light oil, hexane, cyclohexane, etc.), halogenated hydrocarbons (chlorobenzene, dichloromethane, dichloroethane, trichloroethane, etc.), nitriles (acetriform, isobuty) (Ronitrile, etc.), sulfoxides (dimethyl sulfoxide, etc.), heterocyclic solvents (sulfolane, γ-butyrolactone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-octyl-2-pyrrolidone, 1, 3-Dimethyl-2-imidazolidinone), acid amides (N, N-dimethylformamide, N, N-dimethylacetamide, etc.), alkylidene carbonates (propylene carbonate, etc.), vegetable oils (soybean oil, cottonseed oil, etc.), plants Examples include essential oils (orange oil, hisop oil, lemon oil, etc.) and water.

Examples of the surfactant used in the preparation include a nonionic surfactant, an anionic surfactant, a cationic surfactant, and an amphoteric surfactant. Examples of the nonionic surfactant include polyoxyalkylene allylphenyl ether, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene allyl phenyl ether, polyoxyethylene styryl phenyl ether, and polyoxyethylene alkyl phenyl. Ether formaldehyde condensate, polyoxyethylene-polyoxypropylene block polymer, polyoxyethylene-polyoxypropylene block polymer alkylphenyl ether, glycerin fatty acid ester, sorbitan fatty acid ester (eg, sorbitan monooleate, sorbitan laurate), polyoxy Examples thereof include ethylene fatty acid ether, polyoxyethylene fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene hydrogenated castor oil, and polyethylene glycol fatty acid ether. Anionic surfactants include, for example, alkyl sulfate, polyoxyethylene alkyl ether sulfuric acid, polyoxyethylene alkyl phenyl ether sulfuric acid, polyoxyethylene benzyl (or styryl) phenyl ether sulfuric acid or polyoxyethylene-polyoxypropylene block polymer. Sodium, calcium or ammonium salts of sulfate; alkyl sulfonate, dialkyl sulfosuccinate, alkylbenzene sulfonic acid (eg calcium dodecylbenzene sulfonate, etc.), mono- or di-alkylnaphthalene sulfonic acid, formaldehyde condensation of naphthalene sulfonate Mono, lignin sulfonic acid, polyoxyethylene alkylphenyl ether sulfonic acid or polyoxyethylene alkyl ether sulfosuccinate sodium, calcium, ammonium or alkanolamine salts; polyoxyethylene alkyl ether phosphate, polyoxyethylene, mono- Alternatively, salts such as di-alkylphenyl ether phosphate, polyoxyethylene benzyl (or styryl) phenyl ether phosphate, and sodium or calcium salt of polyoxyethylene-polyoxypropylene block polymer phosphate can be mentioned. Examples of the cationic surfactant include a quaternary ammonium salt, an alkylamine salt, an alkylpyridinium salt, an alkyloxide and the like. Examples of amphoteric surfactants include alkyl betaine and amine oxides.

Examples of the propellant used in the preparation include butane gas, chlorofluorocarbon gas, alternative chlorofluorocarbons (HFO, HFC, etc.), liquefied petroleum gas (LPG), dimethyl ether, carbon dioxide gas, and nitrogen gas.
Examples of solid carriers include clays (caolin, diatomaceous earth, bentonite, clay, acidic clay, zeolite, etc.), synthetic silicon hydroxide-containing talc, ceramics, and other inorganic minerals (serisite, quartz, sulfur, activated carbon, calcium carbonate, etc.). Calcium, calcium silicate, hydrated silica, etc.), porous materials, etc. can be mentioned.

The herbicide composition of the present invention can be added with an antifoaming agent, a preservative, an antioxidant, a thickener and the like, if necessary, at the time of preparation of the preparation.
Examples of the defoaming agent include silicone-based defoaming agents and fluorine-based defoaming agents.
Examples of preservatives include organic nitrogen-sulfur compounds, organic bromine compounds, isothiazolin compounds, benzyl alcohol mono (poly) hemiformal, 1,2-benzoisothiazolin-3-one, and 5-chloro-2-methyl-. Examples thereof include 4-isothiazolin-3-one, 2-methyl-4-isothiazolin-3-one, 2-bromo-2-nitropropane-1,3-diol, potassium sorbate, sodium dehydroacetate and the like.
Examples of the antioxidant include tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane, butylated hydroxytoluene (BHT), butylhydroxyanisole (BHA), and propyl gallate. Examples thereof include propyl acid and vitamin E, mixed tocopherol, α-tocopherol, ethoxyquin and ascorbic acid.
Examples of the thickener include polyvinylpyrrolidone, xanthan gum, polyvinyl alcohol, guar gum, carboxyvinyl polymer and the like.

In the herbicide composition of the present invention, for example, the total amount of the first fatty acid salt and the second fatty acid salt of the present invention is preferably 0.05 to 40 g, more preferably 0. It may be sprayed in an amount of 05 to 36 g, more preferably 0.05 to 30 g, and the time of application may be appropriately selected according to the outbreak situation of weeds. In particular, the herbicide composition of the present invention is preferably sprayed directly on the foliage of weeds and also on the soil surface. It is not necessary to spray only on the soil surface, especially when it is sprayed on the soil surface at the same time as weeds are sprayed on the foliage.
By containing the first fatty acid salt and the second fatty acid salt, the herbicidal composition of the present invention exerts contact-type herbicidal activity independently and is excellent in controlling weeds growing on the ground surface. The effect can be obtained. Further, the combined effect of the first fatty acid salt and the second fatty acid salt exerts an excellent germination suppressing effect on the seeds existing in the ground. Due to this contact-type herbicidal activity and an excellent germination-suppressing effect, weeds that grow on the ground surface are killed, and further, germination of new weeds from the ground is suppressed. An excellent herbicidal effect can be obtained over a long period of time.
Therefore, the frequency of application of the herbicide composition of the present invention may be about once every 1 to 2 months after confirming the occurrence of weeds. The means of application is not particularly limited.
Also, the combination of the first fatty acid salt and the second fatty acid salt of the present invention cannot be obtained when the first and second fatty acid salts are simply applied alone, that is, the expected effect is far greater. It has been confirmed by an experiment described later that a synergistic germination inhibitory effect exceeding the above can be obtained.
The details of the mechanism of action for obtaining such a synergistic germination inhibitory effect are unknown, but by combining the first fatty acid salt and the second fatty acid salt, a mutual synergistic action at the point of action level was exhibited. As a result, it is presumed that such a remarkable effect can be obtained.

In addition, for example, a fungicide, a fungicide, an insecticidal acaricide, a repellent, a fragrance, or the like may be used in combination depending on the purpose. For example, bactericides such as bittertanol, bromconazole, cyproconazole, diphenoconazole, hexaconazole, imazalyl, microbutanyl, simeconazole, tetraconazole, thiabendazole, penthiopyrado, manzeb; benzethonium chloride, benzalkonium chloride, chlorhexidine hydrochloride, glucon Antifungal agents such as chlorhexidine acid, hinokithiol, phenoxyethanol, isopropylmethylphenol; insecticide chrysanthemum extract, natural pyrethrin, prarethrin, imiprothrin, phthalthrin, alesulin, bifentrin, resmethrin, phenothrin, ciphenotrin, permethrin, cypermethrin, ethopheneprox , Bifenthrin, fenvalerate, fenpropatrin, empentrin, silafluofen, transfluthrin, metoflutrin, profluthrin and other pyrethroid compounds, carbamate compounds such as carbalyl, propoxul, mesomil, thiodicalbu, oxaziazole compounds such as methoxadiazone, fipronyl. Phenylpyrazole compounds such as, sulfonamide compounds such as amidoflumeth, neonicotinoid compounds such as dinotefuran and imidacloprid, pyrethroid compounds such as chlorphenapir, fenitrothione, diadinone, marathon, pyridafenthion, prothiophos, hoxim, chlorpyriphos, dichlorovos, etc. Pesticides such as organic phosphorus compounds; Diet, di-n-butyl succinate, hydroxyanisole, rotenone, ethyl-butyl acetylaminopropionate, icaridine (pyrethroid), 3- (N-n-butyl-) One or more repellents such as N-acetyl) aminopropionic acid ethyl ester (IR3535) can be used. As the fragrance, one type or a combination of two or more types appropriately selected from the group consisting of natural fragrances, synthetic fragrances and the like can be used depending on the intended use.

The application target of the herbicide composition of the present invention is recognized as a plant that grows around a vegetable garden, a flower bed, etc. and harms the grown crop, or around a house, a vacant lot, a lawn, a garden, a parking lot, etc. It is a weed that grows naturally in graveyards and is recognized as a plant that spoils the aesthetics of the land and causes disaster prevention problems. Specific examples of these weeds include a wide range of first- and perennial broad-leaved weeds and grass weeds.
Typical weeds as weeding targets of the present invention are illustrated below, but the weeds are not limited thereto.
Broad-leaved weeds include, for example, Asagao, Velvet Reef, Hirugao, Shirotsumekusa, Dandelion, Tsubosumire, Chidomegusa, Medhagi, Yabugarashi, Seitakaawadachisou, Erigeron bonarien, American Sendangusa, Itadori, Inugarasi, Inutade, Inubiyu, Humulus japonicus, Kayatsurigusa, Karasunoendo, Gishigishi, Konishikisou, Jishibari, Shiroza, Rorippa palustris, Sugina, Suberihiyu, Seiyodanpopo, Takenigusa, Tsuyukusa, Dokudami, Nazuna, Nogeshi, Noborogiku, Nominofusuma Examples include ragweed, hotokenoza, yaemgra, yomogi, and warnasubi.
Examples of grass weeds include Inubie, Setaria viridis, Setaria pumila, Purplegrass, Poa annua, Poa annua, Eragrostis multica, Akimehishiba, Digitaria ciliaris, Eragrostis ferrugine, Camogaya (orchardgrass), Susuki, Suzumenohie, Chigaya, Chikarashiba.
Examples of places where the herbicide composition of the present invention is applied or used include kitchen gardens, flower beds, around houses, vacant lots, lawns, gardens, parking lots, graveyards, trees, shrubs, golf courses, and the like. It is not limited to these, and can be appropriately used depending on the purpose.

Hereinafter, the present invention will be described in more detail with reference to formulation examples, test examples, and the like, but the present invention is not limited to these examples.
First, an example of a test sample and a germination inhibitory effect of the herbicide composition of the present invention will be described. In the examples, unless otherwise specified, parts mean parts by weight.

<Germination suppression effect confirmation test>
(1) Test Specimen Example 1
2.5 parts by weight of nonanoic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.178 parts by weight of potassium hydroxide as the first base, 1.1 parts by weight of 25% ammonia water as the second base, and purified water. The herbicide composition was prepared using 100 parts by weight of the total amount.
In Examples 2 to 5 and Comparative Examples 1 and 2, the herbicide composition was prepared in the same manner as in Example 1 with the formulations shown in Table 1 below, and the respective test samples were obtained.

(2) Confirmation test method for germination inhibitory effect A solution obtained by diluting the above test sample with purified water 20 times was prepared and used as test sample a.
A filter paper (diameter: 70 mm) was placed on a charley (diameter: 90 mm), white clover seeds (about 50 seeds) were evenly arranged on the filter paper, and 2 mL of each test sample a was dropped on the filter paper. The number of germination after 5 days was confirmed, and the germination rate was calculated by the following formula. In the untreated test, purified water was used instead of the test sample a, and the test did not contain fatty acid salts.
Calculation formula: Germination rate (%) = (number of germination ÷ number of seeds used in the test) x 100
The test was carried out three times, and the germination rate (%) of the test sample a of Comparative Example 2 was converted to 100. The average values of germination rates of Examples 1 to 5 and Comparative Example 1 are shown in Table 1 together with the composition of the test sample.
In Table 1, "KOH" is potassium hydroxide, "25% NH ₃ aq." Is 25% aqueous ammonia, and "blending ratio, 1st base / 2nd base" is the base forming the first fatty acid salt. It means the ratio of the weight of _{ammonia (NH 3} ), which is a base forming the second fatty acid salt, to the weight of potassium hydroxide.

From the results in Table 1, in Comparative Example 1 containing only potassium nonanoate and Comparative Example 2 containing only ammonium nonanoate, seed germination was suppressed as compared with the untreated group, but the suppression thereof. It can be understood that the degree is low.
On the other hand, it is clear that the germination rate of the test specimens a of Examples 1 to 5 in which the potassium nonanoate salt and the ammonium nonanoate salt are used in combination is significantly lower than the germination rate of Comparative Examples 1 and 2. became. In particular, as shown in the results of Examples 1 to 5, a potassium nonanoate salt, which can be understood from the results of Comparative Example 1 to have a low effect of suppressing seed germination, can be used in combination with an ammonium nonanonate salt to cause seed germination. It was confirmed that it was suppressed.
From the above test results, it is possible to significantly suppress the germination of seeds by using the potassium nonanoate salt and the ammonium nonanoate salt in combination as compared with the potassium nonanoate salt and the ammonium nonanoate salt alone, and the germination suppressing effect thereof. Was found to have a synergistic effect beyond the additive effect of mere combination. Moreover, it was also confirmed that the first base and the second base can obtain a synergistic germination inhibitory effect more than the additive effect in a very wide range of the compounding ratio.

<Weeding effect confirmation test>
(1) Test Specimens The test specimens (undiluted) of Example 2 and Comparative Example 2 used in the above "germination suppression effect confirmation test" were used.
(2) Confirmation test method of herbicidal effect Two plots (1 m x 1 m) showing a vegetation coverage ratio (ratio of weeds covering the soil surface) of 95% or more are selected visually, and the weed foliage above the ground is cut with a mower. It was. After leaving nothing on the soil surface, the soil was dug up to about 20 cm from the ground surface with a cultivator, and the weed roots existing in the underground part were removed. By this method, two plots were prepared in which there were no weed foliage and roots in the above-ground part and the underground part, and only weed seeds were present.
The test samples (undiluted) of Example 2 and Comparative Example 2 were sprayed to each section so as to be ^{100 mL / m 2.}
1.5 months after the above spraying, vegetation-covered soil (soil with plants) and non-vegetation-covered soil (soil without plants) are quantified by image analysis software ImageJ for images taken from above of each plot, and soil. The vegetation coverage on the surface was confirmed.
Table 2 shows the vegetation coverage (%) of Example 2 in which the vegetation coverage (%) of the test sample a of Comparative Example 2 was converted to 100.

From the results in Table 2, the test sample of Example 2 in which the potassium nonanoate salt and the ammonium nonanoate salt were used in combination was compared with the test sample of Comparative Example 2 containing only the ammonium nonanoate salt, even in the outdoor test. It was confirmed that it exerts an excellent germination inhibitory effect.
From this result, it was clarified that the herbicidal composition of the present invention exerts an excellent herbicidal effect in an actual use situation.

<Odor confirmation test of herbicide composition>
An odor confirmation test was conducted using the test samples (undiluted) of Example 1, Example 2, Example 5, and Comparative Example 2 of the above-mentioned “germination suppression effect confirmation test”.
In a plastic greenhouse, the test samples of Example 1, Example 2, Example 5, and Comparative Example 2 ^{were sprayed on artificial turf at a spray rate of 100 mL / m 2} , and the odor of nonane acid at the end of spraying was treated by five specialist panelists. The strength of the odor of each test sample was evaluated based on Comparative Example 2.
As a result of evaluation by each panelist, 3 to 5 panelists evaluated that the test samples of Example 1, Example 2, and Example 5 had a weaker odor than the test samples of Comparative Example 2.
From this result, the herbicide composition of the present invention can obtain the desired herbicide effect even if the blending amount of the ammonium salt of nonanoate is reduced by a synergistic effect, and in addition, the odor as the herbicide composition is obtained. Was found to be reduced.
Fatty acids are known to be a group of compounds having a unique odor, but by using two specific fatty acid salts in combination, a herbicide composition containing a fatty acid ammonium salt can be added to the composition. By adding a fatty acid salt other than the fatty acid ammonium salt, the peculiar odor is greatly reduced as compared with the case of the fatty acid or its salt alone, so that the burden on the user is greatly improved.

Claims (5)

In a herbicide composition containing a first fatty acid salt and a second fatty acid salt selected from fatty acid salts having 2 to 10 carbon atoms.
A herbicide composition comprising different types of bases forming the first fatty acid salt and the second fatty acid salt. The herbicide composition according to claim 1, wherein the first fatty acid salt and the second fatty acid salt are the same fatty acid. The herbicide composition according to claim 1 or 2, wherein the first fatty acid salt is a fatty acid potassium salt. The herbicide composition according to any one of claims 1 to 3, wherein the first fatty acid salt is a fatty acid potassium salt and the second fatty acid salt is a fatty acid ammonium salt. A synergistic and long-term weed control method, which comprises using a herbicide composition containing a first fatty acid salt and a second fatty acid salt, which is selected from fatty acid salts having 2 to 10 carbon atoms.