GB2169203A - Herbicidal composition - Google Patents

Abstract

A herbicidal composition comprises a combination of: (A) 2-(4-isopropyl-4-methyl-5-oxo-2-imidazoline-2-yl) nicotinic acid, or an alkali metal salt, a lower alkyl ester or a mono- or di-lower alkyl amine salt thereof, and (B) methyl N-(4-aminophenylsulfonyl) carbamate or an alkali metal salt thereof. The composition may be used to combat weeds in non-agricultural land.

Description

SPECIFICATION Herbicidal Composition This invention relates to a novel herbicidal composition having improved herbicidal properties. More specifically the invention relates to a herbicidal composition containing as the effective ingredient 2-(4-isopropyl-4-methyl-5-oxo-2-imidazoline-2-yl) nicotinic acid or a salt or an ester thereof, and methyl N-(4-aminophenylsulfonyl) carbamate or a salt thereof, in combination, which is particularly valuable as a herbicide to be used in non-agricultural land.

2-(4-lsopropyl-4-methyl-5-oxo-2-imidazoline-2-yl) nicotinic acid or salts or esters thereof are known compounds for their use as non-agricultural herbicides, which have wide weed-killing spectra and durable and strong herbicidal (or weed control) activity, and exhibit the herbicidal activity at a very low application level (see Japanese Laid-Open Patent Publication Sho 57-24364). However, they are extremely slow-acting, and particularly for completely killing perennial herbs which have grown to a certain height, it takes in most cases as long as several months. Thus they sometimes fail to achieve the intended effect within the year of their application, which is a serious drawback with the named compounds.

On the other hand, methyl N-(4-aminophenylsulfonyl) carbamate and salts thereof are the compounds also known as herbicides having such characteristics as showing excellent herbicidal effect against certain perennial weeds, having relatively short residual effect and being slow-acting (see British Patent Specification No. 1,040,541). They have been used in pasture land, lawn, sugar cane field, orchard or the like. However, they fail to show sufficient herbicidal effect against the weeds grown in non-agricultural land, e.g., hard-to-control weeds such as eulalia, etc., even when applied at a considerably high dosage, and furthermore the duration of their effect is short. Thus they can be hardly regarded as suitable for non-agricultural herbicide.

The controlling or killing of weeds in non-agricultural land is in many cases practiced after the weeds grow and overrun the land, and hence the herbicidal compositions are not always applied under the conditions as will allow them to exhibit their highest herbicidal effect. Whereas, the purpose of weed killing in non-agricultural land is predominantly environmental beautification, prevention of crimes, fire prevention, etc., and for such purposes it is highly desirable that the herbicidal effect be quickly manifested after application of the herbicide. In the past, however, there has been no non-agricultural herbicide fully meeting these requirements available.

2-(4-lsopropyl-4-methyl-5-oxo-imidazoline-2-yl) nicotinic acid or salts or esters thereof have been developed as non-agricultural herbicides as aforesaid, but because the weeds applied with those compounds wither in the state of so-called "standing dead", the result is unfavorable from the standpoint of crime or fire prevention.

And, the development of a non-agricultural herbicide which exhibits excellent herbicidal (or weed control) effect against also those hard-to-control non-agricultural weeds, particularly those thickly grown, which furthermore is fast-acting and the weeds applied therewith will fall and decay, has been strongly desired.

The present invention is proposed to meet the foregoing demand, according to which a herbicidal composition which comprises a combination of (A) 2-(4-isopropyl-4-methyl-5-oxo-imidazoline-2-yl) nicotinic acid, or an alkali metal salt, a lower alkyl ester or mono- or di-lower alkylamine salt thereof (which will be heretofore collectively referred to as "nicotinic acid derivatives"), and (B) methyl N-(4-aminophenylsulfonyl) carbamate or an alkali metal salt thereof (hereinafter "carbamate derivatives") is provided.

The herbicidal composition provided by the present invention exhibits excellent herbicidal activity as the nicotinic acid derivative and carbamate derivative contained therein act synergistically, is fast-acting and has long-durable effect, and furthermore has the advantage that the weeds applied with the herbicidal composition of this invention fall down after being withered and decay. Thus the composition is particularly useful as a non-agricultural herbicide.

In the present specification and appended claims, the term "lower" is used to denote that the number of carbon atoms contained in the group or compound attached with that term is not more than 6, preferably not more than 4.

As the nicotinic acid derivatives which are used as one of the components of the combined herbicidal composition of this invention, examples of useful alkali metal salts of 2-(4-isopropyl-4-methyl-5-oxo-2imidazoline-2-yl) nicotinic acid include sodium salt, potassium salt and lithium salt. Also the lower alkyl esters include methyl ester, ethyl ester, n-propyl ester, isopropyl ester, n-butyl ester, isobutyl ester, sec-butyl ester and tert-butyl ester. Examples of the mono- or di-alkylamine salt include monoethylammonium salt, mono-n-propylammonium salt, mono-isopropylammonium salt, mono-n butylammonium salt, mono-isobutylammonium salt, mono- sec-butylammonium salt, mono-tert butylammonium salt, diethylammonium salt and di-n-propylammonium salt.

As the carbamate derivatives which are used as the other component of the combined herbicidal composition of this invention, examples of useful alkali metal salts of methyl N-(4-aminophenylsulfonyl) carbamate include sodium salt, potassium salt and lithium salt.

The blend ratio of the nicotinic acid derivative and carbamate derivative in the combined herbicidal composition of this invention is variable depending on the form of preparation, method of application, etc.

Generally, however, normally 0.1 to 10 parts by weight, preferably 0.2 to 6 parts by weight, inter alia, 0.5 to 4 parts by weight of the carbamate derivative is used per one part by weight of the nicotinic acid derivative.

In applying the combination of the nicotinic said derivative and carbamate derivative in accordance with the present invention, the combination can be formulated into the various forms of preparation normally employed for herbicidal compositions, for example, dust, granules, wettable powder, solution, emulsion, flowable matter, etc., together with agronomically acceptable carriers or diluents.

As the agronomically acceptable carriers and diluents to be used for formulating the combination, those suitable for the intended form of preparation can be selected from the materials as below-listed and suitably combined: water; organic solvents such as isophorone, cyclohexanone and ethylene glycol; inert inorganic material such as kaolin, talc, diatomaceous earth, bentonite, silica, clay, zeolite and calcium carbonate; dispersing agents or spreading agents such as anionic surfactants and non-ionic surfactants; and alkylbenzene sulfonates, alkylnaphthalene sulfonates, alkylsulfosuccinates, alkylphosphates, polyoxyethylene alkylethers, polyoxyethylene alkylarylethers and esters of sorbitan aliphatic acids.

The herbicidal composition of this invention may further contain, if required, other agronomically active substances such as known herbicide, plant growth regulator, defoliating agent, germicide, insecticide, nematocide, etc., as normally practiced.

The contents of nicotinic acid derivative and carbamate derivative in the so formulated composition of this invention are variable depending on the form of preparation, etc., but generaliy it is desirable that the total content of nicotinic acid derivative plus carbamate derivative should be within the range of 1 to 80% by weight, based on the total weight of the composition. More specifically, the preferred total content ranges from 1 to 10% by weight with dust or granules, 40 to 80% by weight with wettable powder, and 20 to 50% by weight with solution.

The herbicidal composition of this invention exhibits synergistically excellent herbicidal effect, and particularly exhibits strong and fast-acting herbicidal activity against non-agricultural weeds such as the graminaceous perennial weeds, e.g., eulalia, needle-grass, common reed (Phragmites communis), Johnson grass (Sorghum halepense); broadleafed perennial weeds, e.g., Solidago altissima, biennial wormwood (Artemisia princeps) arrowroot (Pueraria lobata), Japanese knotweed (Polygonum cuspidatum), and Taraxacum officinale, etc.; perennial weeds of Cyperaceae and Equisetaceae; and annual weeds, e.g., green foxtail (Setaria viridis), crabgrass (Digitaria ciliaris), barnyard grass, Erigeron banariensis, ragweed (Ambrosia artemislifolla), Chemopodium album, Amaranthus viridis, etc.

And, for the combat with these weeds using the composition of this invention, the herbicidally effective amount of the combination of the nicotinic acid derivative and carbamate derivative is applied either directly to the stems of the weeds to be killed, orto the soil before emergence of these weeds.

The respective dosage of the nicotinic acid derivative and carbamate derivative are variable depending on the form of application (foliar treatment or pre-emergence soil treatment), form of preparation and types of the weed(s) to be killed. Generally speaking, however, they are suitably within the range each 0.1-1 glum2, preferably 02-0.6 glum2, as converted respectively to 2-(4-isopropyl-4-methyl-5-oxo-2-imidazoline-2yl) nicotinic acid and methyl N-(4-aminophenylsulfonyl) carbamate.

Hereinafter the herbicidal effect and methods of formulating the herbicidal composition of this invention will be more specifically explained, referring to the experiments and working examples, in which the nicotinic acid derivatives and carbamate derivatives as identified in Tables I and II below were used.

TABLE I Nicotinic Acid Derivatives

Compound No. Compound 1 2-(4-isopropyl-4-methyl-5-oxo-2 imidazoline-2-yl) nicotinic acid 2 its sodium salt 3 its diethylammonium salt 4 its mono-isopropylammonium salt 5 its ethyl ester 6 its n-butyl ester TABLE II Carbamate Derivatives

Compound No. Compound 11 Methyl N-(4-aminophenylsulphonyl) carbamate 12 its sodium salt In the following experiments, the concentrations or application dosages of the compounds Nos. 2 through 6 are indicated by the values as converted to the compound No. 1, and the concentration or application dosage of the compound No. 12 is indicated by the value as converted to the compound No. 11.

Experiment 1 (Foliar Treatment of Crabgrass) On the crabgrass at its 5th leaf stage having a height of about 20 cm, grown in advance in unglazed pots of 100 cm2 each, diluted solutions (solvent:water) of the test compounds were sprayed in an application amount of 100 milt2, either separately or as mixed, and the rate of weed-control was observed.The results were as shown in Table Ill below, which were evaluated on a scale of 10 grades as follows: 0: weed growth similar to that in untreated pot 2: 20% control 4: 40% control 6: 60% control 8: 80% control 10: complete control TABLE Ill: (Foliar Treatment of Crabgrass)

Results of Survey Nicotinic Acid Carbamate Derivative Derivative Number of Weeks Compound No. Compound No. 11 after Treatment Concentration Concentration No. (%) (%) 1 2 4 0.03 0 1 6 0.1 0 2 8 0.3 - 0 3 9.5 0.03 0.1 3 9 10 0.1 0.1 5 9.5 10 0.3 0.1 7 10 10 0.03 ~ 0 2 7 0.1 0 2 9 0.3 0 3 9.5 2 0.03 0.1 5 9.5 10 0.1 0.1 6 9.5 10 0.3 0.1 7 10 10 0.03 - 0 2 7 0.1 0 3 9 0.3 - 0 4 9.5 4 0.03 0.1 5 9.5 10 0.1 0.1 6 10 10 0.3 0.1 8 10 10 0.03 - 0 1 6 0.1 0 2 7 0.3 0 3 9 5 0.03 0.1 4 9 10 0.1 0.1 5 9 10 0.3 0.1 6 10 10 0.1 0 3 4 Experiment 2: (Foliar Treatment of Crabgrass) Diluted solutions of Compounds No. 2 and No. 12 (solvent: water) were sprayed onto the crabgrass at its 4--5th leaf stage having a height of 1520cam, grown in advance in each 100 cm2-unglazed pot, either -separately or as combined, in an application amount of 100 ml/m2, using a spray gun. Table IV shows the results of the survey 2 weeks after the treatment. The evaluation was done by the same scale as employed in Experiment 1.

TABLE IV

No. 12 Compound Concentration No. (%) 0 0.01 0.02 0.04 0.08 0.16 0.32 0 - 0 0 1 3 4 6 0.01 4 7 7 9 10 10 10 0.02 4 7 8 9.5 10 10 10 No. 2 0.04 5 8 8 10 10 10 10 0.08 6 8 9 10 10 10 10 0.16 6 1 9 9.5 10 10 10 10 0.32 7 9 10 10 10 10 10 Experiment 3: (Field Test) Test flats of each 2.5mx2.5m size predominantly covered with graminaceous perennial weeds such as eulalia (Muscanthus) and needle-grass (Imperata cylindrica), and those predominantly covered with broadleafed perennial weeds such as Solidago altissima and biennial wormwood (Artemisia princeps), which are typical hard-to-control non-agricultural weeds, were selected, and onto which Compounds No. 4 and No. 12 were uniformly sprayed in the form of aqueous dispersions either separately or as combined, at a total application amount of 300 ml/m2, with a watering pot. The aqueous dispersions were sprayed on July 5, and observations were made 2 weeks, one month, 2 months, and 3 months after the spraying. Tables V-l and V-2 give the results.

Evaluations were made for each grass by the same scale as employed in Experiment 1. The conditions of the weeds at the time of the treatment were as follows: Rate of Occupancy NameofGrass Within the Flat Height of Grass (%) (cm) Muscanthus 5Q80 120150 Imperata 6080 60-80 Solidago 50-70 7O100 Artemisia 4060 40-70 TABLE V-1:Field Test (Graminaceous Perennial Weeds)

Amount of Test Results of Survey Compound Applied gim2 After Treatment Name of Compound Compound 2 1 2 3 Grass No. 4 No. 12 Weeks Month Months Months 0.1 - 1 2 4 7 0.2 - 1 3 5 8 0.4 - 2 4 7 9.5 0.1 0.15 2 8.5 10 10 0.2 0.15 3 9.5 10 10 Muscanthus 0.4 0.15 5 10 10 10 0.1 0.3 5 9 10 10 0.2 0.3 5 9.5 10 10 0.4 0.3 6 10 10 10 - 0.15 1 3 2 1 0.3 2 4 3 1 0.1 - 0 1 3 5 0.2 - 0 1 4 6 0.4 - 0 2 5 8 0.1 0.15 3 9 10 10 0.2 0.15 4 9.5 10 10 Imperata 0.4 0.15 5 9.5 10 10 0.1 0.3 5 9.5 10 10 0.2 0.3 6 10 10 10 0.4 0.3 7 10 10 10 - 0.15 1 3 2 0 - 0.3 2 5 4 2 TABLE V-2:Field Test (Broadleafed Perennial Weeds)

Amount of Test Results of Survey Compound Applied gim2 After Treatment Name of Compound Compound 2 1 2 3 Grass No. 4 No. 12 Weeks Month Months Months 0.1 - 2 4 5 9 0.2 - 3 5 6 9.5 0.4 - 4 7 9 10 0.1 0.15 6 8.5 9 10 0.2 0.15 7 8.5 10 10 Solidago 0.4 0.15 8 9 10 10 0.1 0.3 6 9 10 10 0.2 0.3 8 9.5 10 10 0.4 0.3 8.5 10 10 10 - 0.15 1 4 3 2 - 0.3 2 6 5 4 0.1 - 3 5 9 9.5 0.2 - 5 7 9.5 10 0.4 - 5 8 9.5 10 0.1 0.15 8 9.5 10 10 0.2 0.15 9 10 10 10 Artemisia 0.4 0.15 9 10 10 10 0.1 0.3 9 10 10 10 0.2 0.3 9.5 10 10 10 0.4 0.3 9.5 10 10 10 0.15 1 3 4 3 - 0.3 2 6 7 7 Experiment 4 (Effect of Granular Preparation) Crabgrass was grown in each 100 cm2 unglazed pot filled with diluvial volcanic ash soil, and at their 4th leaf stage (height: about 15cm), a 1% granular preparation of Compound No. 6 and a 2% granular preparation of Compound No. 12 which were prepared in the manner similar two later-appearing Example 3 were manually uniformly applied onto the soil surfaces in the pots, either separately or as combined. After the application, artificial rain was given to the soil 1-3 times a day depending on moisture content of the soil, to keep the soil at somewhat highly moist condition. The results of visual observation results of the test pots on 20th day after the treatment were as given in Table VI below.The norm of evaluation employed is same to that used in Experiment 1.

TABLE Vl

No. 12 (2% Granular Compound No. Preparation) Dose gIm2 0 5 10 20 40 0 - 1 2 4 7 5 5 8 9.5 10 10 No. 6 10 5 9 9.5 10 10 (1% Granular Preparation) 20 ; 6 9 10 10 10 40 | 7 9.5 10 10 10 Experiment 5 (Field Test of Granular Preparation) Test flats each 2mx2m in size were chosen in a created land predominantly covered with field horsetail (Equisetum palustre), onto which the composition of this invention and the two effective ingredients in the forms of granular preparations which were prepared in the manner similar to later-appearing Example 3 were manually uniformly dispersed. The treatment was performed on August 2, and the flats were visually examined at two weeks, a month, and two months thereafter, with the results as indicated in Table VII below. The norm of evaluation employed is same to that used in Experiment 1.

TABLE VII

Results of Survey After Treatment Application Compound Content Amount 2 1 2 No. (%) g/m2 Weeks Month Months 10 0 0 4 No. 2 1 20 0 2 5 40 0 3 7 10 0 0 0 No. 12 2 20 0 2 2 40 0 4 5 Composition 10 3 9 10 of Present invention 1+2 20 5 9.5 10 (No. 2 Plus No. 12) 40 6 10 10 Experiment 6 (Field Test of Dust Preparation) Test flats of each 7m x7m in size were chosen in the land mowed once before end of the rainy season but again thickly covered with such perennial weeds as eulalia (Muscanthus), needle-glass (Imperata) Lespedeza cuneata and biennial wormwood (Artemisia) as well as common ragweed (Ambrosia artemisiifolia) and green foxtail (Setaria viridis).A dust preparation of the composition of this invention containing 2% of Compound No. 4 and 3% of Compound No. 12, which was prepared in the manner similar to later-appearing Example 4, was manually uniformly dispersed onto the test flats at the application amounts of 10 g/m2 and 20 g/m2. The treatment was performed on August 2, and the test flats were visually observed at two months and three months after the date of dispersion, with the results as indicated in Table VIII. The herbicidal effect was proven satisfactory. The norm of evaluation is same to that used in Experiment 1.

TABLE VIII Height of Grass Amount of Results of Survey at the Time of Treatment Type of Grass Treatment (cm) 9lem2 1 Month 2 Months Muscanthus 5080 10 7 10 20 9 10 Imperata 3050 10 6 9.5 20 9 10 Lespedezacuneata 50-80 10 6 9.5 20 9 10 Artemisia 2040 10 9.5 10 20 10 10 Ambrosia artemisiifolia 30-.60 10 10 10 20 10 10 Setaria viridis 2Q30 10 9.5 10 20 10 10 Example 1 (Wettable Powder) To 2-(4-isopropyl-4-methyl-5-oxo-2-imidazoline-2-yl) nicotinic acid (Compound No.1) and methyl N-(4-aminophenylsulfonyl) carbamate (Compound No. 11), kaolin clay and white carbon were added, stirred and mixed in a grinder, and the system was further thoroughly mixed with powdery surfactants to provide a wettable powder containing 25% of Compound No. 1 and 20% of Compound No. 11.

Compound No. 1 25 parts w/w Compound No.11 20 parts w/w Kaolin clay 45 parts w/w White carbon 5 parts w/w Sorpol 5039 (polyoxyethylene alkylarylether sulfate absorbed in white carbon: trademark of Toho Kagaku) 4 parts w/w Rabisol BB-75 (dioctylsulfo succinate absorbed in white carbon: trademark of Nihon Yushi) 1 part w/w Example 2 (Liquid Preparation) A nicotinic acid derivative (Compound No.4), a carbamate derivative (Compound No. 12) and a surfactant were dissolved in an ion-exchange treated water, to provide a liquid preparation of the composition of this invention, which contained 12% of Compound No.4 and 18% of Compound No. 12.

Compound No.4 12 parts w/w Compound No. 12 18 parts w/w Polyoxyethylenearylether 5 parts w/w lon-exchange treated water 65 parts w/w Example 3 (Granular Preparation) A nicotinic acid derivative (Compound No. 6), a carbamate derivative (Compound No, 11), bentonite, clay and a surfactant were mixed, and uniformly kneaded in a kneader with addition of water. The kneaded product was pelletized with a pelletizer and dried in an air-current to provide the composition of the present invention as a granular preparation, containing 1% of Compound No.6 and 2% of Compound No.11.

Compound No.6 1 part w/w Compound No.11 2 parts w/w Dioctylsulfosuccinate 1 part w/w Bentonite 40 parts w/w Clay 56 parts w/w .

Example 4 (Dust Preparation) A nicotinic acid derivative (Compound No.4) and a carbamate derivative (Compound No. 12) were diluted with water, and injected into fine particulate zeolite (48150 mesh) under stirring in a speed kneader. Into the system further a surfactant diluted with water was added, followed by additional stirring.

Then white carbon was added thereto and system was withdrawn from the kneader. Upon drying the same in an air-current, the composition of this invention as a dust preparation containing 2% of Compound No.4 and 3% of Compound No. was obtained.

Compound No.4 2 parts w/w Compound No. 12 3 parts w/w Fine particulate zeolite 90 parts w/w Polyoxyethylene dodecylether 2 parts w/w White carbon 3 parts w/w

Claims (7)

1. A herbicidal composition which comprises a combination of the following components: (A) 2-(4-isopropyl-4-methyl-5-oxo-2-imidazoline-2-yl) nicotinic acid, or an alkali metal salt, a lower alkyl ester or a mono- or di-lower alkyl amine salt thereof, and (B) methyl N-(4-aminophenylsulfonyl) carbamate or an alkali metal saltthereof.

2. The herbicidal composition of Claim 1 which comprises 1 part by weight of the component (A) and 0.1-10 parts by weight of the component (B).

3. The herbicidal composition of Claim 2 which comprises 1 part by weight of the component (A) and 0.2-6 parts by weight of the component (B).

4. The herbicidal composition of Claim 1 which is in the form of dust, granules, wettable powder or liquid.

5. The herbicidal composition of Claim 1 in which the total content of the components (A) and (B) is from 1 to 80% by weight based on the total weight of the composition.

6. A method for combatting with weeds, which comprises applying a herbicidally effective amount of a combination of the following components: (A) 2-(4-isopropyl-4-methyl-5-oxo-2-imidazoline-2-yl) nicotinic acid, or an alkali metal salt, a lower alkyl ester or a mono- or di-lower alkyl amine salt thereof, and (B) methyl N-(4-aminophenylsulfonyl) carbamate or an alkali metal salt thereof.

7. The method of Claim 6 in which the application amounts of the components (A) and (B) are each 0.1-1 g/m2.