NL7909099A - METHOD FOR CONTROLLING WEEDS IN CEREALS AND HERBICIDES. - Google Patents

Description

N / 29.376-Kp / vdM 4 - 1 - r

Method for controlling weeds in grain fields and herbicides.

The invention relates to a method for controlling weeds in grain fields, as well as to herbicides, which are suitable, inter alia, for use in this method.

In order to control a large number of weeds in agricultural crops, eg cereals, it is often necessary to use more than one herbicide. Despite the use of such mixtures, weeds still appear to be resistant to herbicide treatment, with the result that damage is caused to both winter and spring cereals, eg wheat, barley, oats and rye.

It has now been found that specific combinations of herbicides are suitable not only for a broad spectrum of weed control, but also that they are surprisingly effective against weeds, especially broad-leaf weeds, in cereals.

Accordingly, the invention provides a method of controlling weeds, in particular broadleaf weeds, in grain fields, characterized in that on the grain fields after the germination of the crops, bifenox of the formula of the formula sheet, together with one or more other active ingredients, including (1) a benzoic acid herbicide, which is dicamba or 2,3,6-TBA or a salt or an ester thereof, (2) a phenoxy acid herbicide, which is dichloroprop or 2,4- DB or a salt or an ester thereof, (3) a dinitrophenol herbicide, which is DNOC, dinoterb or dinoseb or a salt or an ester thereof, (4) a benzonitrile herbicide, which is ioxynil or bromoxynil or a salt or an ester thereof , (5) benazoline or a salt or an ester thereof, (6) benta sun or (7) 3,6-DCP or a salt or an ester thereof, is applied.

It will be clear that more than one of the active components (1) to (7) can be used according to the present method and that in addition other herbicidal active compounds of the kind can be used. as the components (1) to (7). When the active ingredient is an acid or phenol, one can use derivatives such as salts and esters, provided of course that they are not substantially more phytotoxic than the free acid or phenol.

The nature of such salts and esters is known to the person skilled in the art.

The preparation of biphenox, methyl 5- (2,4-dichloro-phenoxy) -2-nitrobenzoate, is described in British Patent No. 1,232,368, while its use as a herbicide is disclosed in Proc. N.E. Weed Sci. Conf. 1973, 2-7, 31.

Likewise, the benzoic acid herbicide dicamba, which compound is 3,6-dichloro-2-methoxybenzoic acid, is described in U.S. Patent 3,013,054, while 2,3,6-TBA, which is 2,3, β-trichlorobenzoic acid, is known from U.S. Pat. Nos. 2,848,470 and 3,081,162. The phenoxyacid herbicides are a known group of compounds, which have been widely available for some time. Dichlorprop is a general designation for 2- (2,4-dichlorophenoxy) propionic acid, which compound is also known as 2,4-DP; 2,4-DB is the general name for 4- (2,4-dichlorophenoxy) butyric acid. The di-nitrophenol herbicide, DNOC (chemical designation 2-methyl-4,6-dinitrophenol) was introduced under the protection of British Patent 425,295; dinoseb is the general term for 2-sec-butyl-4,6-dinitrophenol, disclosed in U.S. Patent 2,192,197; while dinoterb, 2-tert-butyl-4,6-dinitrophenol is described, inter alia, in British Pat. 126,658. The benzonitrile herbicides ioxynil (4-hydroxy-3> 5-diiodobenzonitrile) and bromoxynil (3,5-dibromo-4-hydroxybenzo-30 nitrile) are both described, for example, in British Patent 977,755. Benazoline of the chemical structural formula 4-chloro-2-oxo-3-benzothiazolinacetic acid is disclosed in British patent 862,226 and bentazone, which is the general designation for 3-isopropyl-1 (1H) -benzo-2,3-thiadiazin -4-35 on-2,2-dioxide is known from U.S. Pat. No. 3,70,8,277. 3,6-DCP, which is 3,6-dichloropicolinic acid, is described in U.S. Patent 3,317,549.

The cereals can be eg wheat, barley, oats or rye, while the present process finds its greatest strength in the treatment of wheat and barley, especially winter wheat and spring and winter barley. The sensitivity of the crops, as well as the severity of the weed problem, determine the amount of active components to be applied. Generally, however, bifenox is applied in an amount of 0.25-3.0 kg / ha, preferably in an amount of 0.5-1.5 kg / ha and most preferably in an amount of 0.5-0 .75 kg / ha.

The preferred application amounts of the active components (1) to (7) are listed below. When a component is derived from an acid or phenol, the amounts are based on the free acid or phenol equivalent.

For example, when a benzoic acid herbicide, e.g. dicam-15 ba or 2,3,6-TBA is used, it is preferably used in an amount of 0.05-0.2 kg / ha, while the weight ratio of the bifenox until the benzoic acid herbicide is usually 60: 1 to 1: 1, and preferably 30: 1 to 4: 1. The benzoic acid herbicide can be used in the form of a salt thereof, in particular an alkali metal salt, such as sodium or potassium salt, or in the form of an ester thereof, eg a C 1 -C 8 alkyl ester.

When using a phenoxy acid herbicide, which is dichloroprop or 2,4-DB, such a herbicide is applied in an amount of 0.1-3.5 kg / ha, at a weight ratio of the biphenox to the phenoxy acid herbicide usually from 30: 1 to 1: 15, especially from 8: 1 to 1: 6. In a particularly preferred embodiment, the biphenox is applied in an amount of 0.5-0.75 kg / ha and the phenoxy acid herbicide in an amount of 1.5-3.0 kg / ha. . The phenoxy acid herbicide is usually used in the form of a salt thereof, e.g. an alkali metal salt, in particular sodium or potassium salt, or as an amine or an ammonium salt. Examples of the ester forms of the phenoxyacid herbicide are those ester forms containing 1-8 carbon atoms in the ester group, e.g., ethyl, isopropyl and butyl esters.

9 0 9 0 9 ^ n ^ ing of dinitrophenol herbicide, which is 9 '- 4 - DNOC, dinoterb or dinoseb, this is preferably used in an amount of 0.5-5.0 kg / ha and the preferably in an amount of 0.5-2.0 kg / ha when it comes to dinoterb or dinoseb. The weight ratio of bifenox to dinitrophenol herbicide is preferably 6: 1 to 1:20 and most preferably from 3: 1 to 1: 6. Examples of suitable salt forms of the dinitrophenol herbicide are those formed from both inorganic and organic bases, in especially the amine and ammonium salts. Examples of esters are those formed with 10 organic acids, eg carboxylic acids, eg dinose acetate.

When using benzonitrile herbicide, which is ioxynil or bromoxynil, it is preferably applied in an amount of 0.05-0.5 kg / ha, most preferably in an amount of 0.1-0.35 kg / ha. The weight ratio of 15 bifenox to the benzonitrile herbicide is preferably 60: 1 to 1: 2, most preferably 15: 1 to 2: 1. In a particular embodiment, both ioxynil and bromoxynil are used in conjunction with the bifenox, in which case the preferred amounts and weight ratios are based on the total weight of both the ioxynil and the bromoxynil. The preferred salt forms of the ioxynil and the bromoxynil are the alkali metal salts, e.g., of sodium and potassium. Preferred esters are oxyniloctanoate and bromoxyniloctanoate.

When using benazoline, it is preferably applied in an amount of 0.05-0.25 kg / ha.

The weight ratio of bifenox to benazoline is preferably 60: 1 to 1: 1, most preferably 15: 1 to 5: 2. Suitable salt forms of the benazoline are those of an alkali metal, in particular sodium and potassium. The preferred esters are the esters, the ester group of which contains 1-4 carbon atoms, in particular the ethyl ester.

When using bentazone it is preferably applied in an amount of 0.1-1.5 and even more preferably in an amount of 0.2-1.5 and most preferably in an amount of 0.5-1.5 kg. / ha. A preferred weight ratio of bifenox to bentazone is 6: 1 to 1: 6, most preferably 3: 1 to 1: 2.

When using 3,6-DCP this is preferably applied in an amount of 0.025-0.15 kg / ha and the 7909093 ♦ -5 - * most preferably in an amount of 0.05-0.1 kg / ha. A preferred weight ratio of bifenox to 3,6-DCP is 30: 1 to 3: 1, most preferably from 15: 1 to 5: 1. Examples of salt forms of the 3,6-DCP are the alkali metal salts, eg those of sodium and potassium and the amine and ammonium salts, eg the monoethanolamine salt. Examples of esters are those containing from 1 to 8 carbon atoms in the ester group.

The present method is preferably carried out when the cereal crops are between the one-leaf stage and the appearance of the second nodule.

When the bifenox is used together with the benzoic acid herbicide, a very good control of the weed varieties Stellaria media, Polygonum spp, Spergula arvensis, Tripleurospermum maritimum, Viola spp and Veronica 15 spp takes place.

When bifenox is used together with the phenoxy acid herbicide, the weed species Galium aparine, Stellaria media and Veronica spp can be successfully controlled.

When bifenox is used together with the di-trophenol herbicide, a very good control takes place of the weed species Galeopsis tetrahit, Fumaria officinalis, Polygonum convulvulus and Galium aparine.

When bifenox is used together with benzoni-25 vibratory herbicide, a good control of the weed species Matricaria spp. Polygonum spp and Galium aparine.

When bifenox is used together with benazoline, a very good control appears to take place of the weed species Stellaria media, Galium aparine and Viola spp.

When using the bifenox together with bentazone, a very good control appears to take place of the weed species Viola spp, Veronica spp and Matricaria spp.

When using bifenox together with 3,6-DCP, very good results are obtained in the control of the on-herb species Veronica spp and Matricaria spp.

Examples of other herbicidally active compounds which can be used together with the bifenox and component (1) to component (7) are MCPA, MCPB and mecoprop, 7909099 «i - 6 -» each a known herbicide, in connection with referring to "Pesticide Manual", fifth edition, published by the British Crop Protection Council.

The bifenox and the active ingredient (s) (1) to 5 (7) can be applied to the crop fields together with other herbicidally active compounds, either simultaneously or separately. In the latter case, the time period between application should preferably be short, i.e. 1 day or less. However, it is further preferable if the compounds are applied simultaneously in the form of a mixture. In order to simplify the preparation, storage and transport, the herbicide mixtures are usually prepared in the form of a concentrate, which is then diluted with water 1-5 before application, to the desired concentration of the active substances, which dilution is generally is such that the final mixture to be applied contains 0.05-3.0% by weight of the herbicidally active components. The concentrates generally contain 1-90%, preferably 15-85% of the active ingredients, combined with one or more non-phytotoxic carriers or diluents.

The concentrates are included in the invention. Thus, the invention also provides a concentrated herbicide mixture, which can be used in particular, but not exclusively, for the present process, which concentrate bifenox, one or more other components such as (1) a benzoic acid herbicide, which is dicamba or 2,3, 6-TBA or a salt or an ester thereof, (2) a phenoxy acid herbicide, which is dichloroprop or 2,4-DB or a salt or an ester thereof, (3) a dinitrophenol herbicide, containing DNOC, dinoterb or dinoseb or a salt or an ester thereof, (4) a benzonitrile herbicide which is ioxynil or bromoxynil or a salt or an ester thereof, (5) benazoline or a salt or an ester thereof, (6) bentazone or (7) 3.6- DCP or a salt or an ester thereof, together with one or more non-phytotoxic carriers or diluents.

In such a mixture, the weight ratios of bifenox to each of components (1) through (7) are preferably in the range indicated above.

7909099 <- 7 -

The concentrates according to the invention are usually in the form of a wettable powder, an emulsifiable concentrate or an aqueous suspension. The use of aqueous suspensions or wettable powders is preferred according to the invention, because this results in a significantly lower phytotoxicity compared to the cereals compared to the use of an emulsifiable concentrate.

Wettable powders include an intimate mixture of the active ingredients, one or more inert carriers and suitable surfactants. The inert carrier can be, for example, attapulgite clay, montmorillonite clay, diatomaceous earth, kaolin, mica, talc or purified silicon dioxide. Examples of suitable surfactants are sulfonated lignins, naphthalene sulfonates, condensed naphthalene sulfonates, alkyl succinates, alkyl benzene sulfonates, alkyl sulfates and nonionic surfactants such as ethylene oxide adducts of phenol.

Emulsifiable concentrates contain the active ingredients in the dissolved state in a suitable solvent or suitable solvents, together with a surfactant. Suitable surfactants are, for example, those mentioned in connection with the wettable powders. Suitable solvents are alkyl-substituted benzenes, o-chlorotoluene, heavy aromatic naphthalenes, glycol ethers and cyclic ketones.

Aqueous suspensions and solutions contain the active ingredients in suspended or dissolved form in water or in suitable solvents, together with a desired surfactant, thickener, antifreeze or preservatives. Examples of suitable surfactants are those mentioned in connection with the wettable powders. When used with diluents, they are normally a suitable cellulosic material or a natural gum, while glycols are generally used when an anti-freeze is desired. Examples of preservatives are materials such as the various paraben antibacterial agents, phenol, o-chlorocresol, phenylmericinitrate and formaldehyde.

7909099 - 8 -

Alternatively, the herbicide mixtures can be prepared by mixing the two or more active ingredients with water in a spray tank just prior to use, the water serving as a non-phytotoxic carrier. Such mixing requirements are called "tank mixes" and constitute another aspect of the invention. In such tank mixes, the weight ratios of bifenox to the other component (1) through (7) are again preferably selected as set forth above.

The following examples illustrate the concentrated herbicide mixtures of the invention. When a herbicide component is a derivative of an acid or a phenol, the amount is based on the acid or phenol equivalent. EXAMPLES I-X

The following wettable powders were prepared from the components listed below.

EXAMPLE I Wt. % bifenox 25 bentazone 25 sodium alkyl ether sulfate 3 20 sulfonated lignin 2 precipitated silica 6 talc to 100

EXAMPLE II

bifenox 50 25 ioxynil 5 sodium salt of condensed naphthalene sulfonic acids 2 ethoxylated alkyl phenol 4 fumed silica 5 30 montmorillonite to 100

EXAMPLE III

bifenox 42 bromoxynil 6 sodium lauryl sulfate 5 35 sodium lignin sulfonate 3 precipitated silica 8 kaolin to 100 7909099-9 EXAMPLE IV wt. % bifenox 48 benazoline (ethyl ester) 4 ethoxylated nonylphenol 4 5 sulfite lye powder 4 fumed silica 5 attapulgite to 100

EXAMPLE V

bifenox 40 10 3,6-DCP (monoethanolamine salt) 4 sodium lauryl sulfate 4 sodium lignin sulfonate 3 precipitated silica 8 kaolin to 100

EXAMPLE VI

bifenox 20 2,4-DB (potassium salt) 30 ethoxylated alkyl phenol 2 sulfite lye powder 4 20 fumed silica 5 attapulgite to 100

EXAMPLE VII

bifenox 20 dichloroprop (potassium salt) 40 25 sodium dialkyl sulfosuccinate 3 lignosulfonate - 2 "micronised" silica 7 diatomaceous earth up to 100

EXAMPLE VIII

Bifenox 45 ioxynil 2.5 bromoxynil 3 sodium lauryl sulfite 2 sodium lignin sulfonate 3 35 precipitated silica ^ 5 montmorillonite up to 100 7909099 # λ - 10 - EXAMPLE IX wt. % bifenox 40 2,3,6-TBA (sodium salt) 5 sodium lauryl sulfate 3 5 sodium lignin sulfonate 3 precipitated silica 4 kaolin to 100

EXAMPLE X

bifenox 40 10 dicamba (sodium salt) 4 ethoxylated alkyl phenol 4 lignosulfonate 2 fumed silica 3 sodium aluminum silicate up to 100

In each of the examples, the active ingredients were carefully mixed with the listed excipients in a conventional mixer. The mixture was then further mixed in a liquid energy mixer, yielding particles of 1-10 µm in size. EXAMPLES XI-XXII

The following emulsifiable concentrates were prepared from the ingredients below.

EXAMPLE XI qew. % bifenox 25 25 ioxynil (octanoate) 3 calcium dodecylbenzenesulfonate 4 alkylphenoxypolyoxyethylene ethanols 2 cyclohexanone 35 30 xylene to 100

EXAMPLE XII

bifenox 20 bromoxynil (octanoate) 4 amine salt of dodecylbenzene-35 sulfonic acid 3 polyoxyethylene triglyceride 3 cyclohexanone 30 orthochlorotoluene to 100 7909099 4- - 11 - * EXAMPLE XIII qew. % bifenox 20 benazoline (ethyl ester) 2 calcium dodecyl benzene sulfonate 2 5 ethoxylated alkyl phenol 4 isophorone 35 heavy aromatic naphtha up to 100

EXAMPLE XIV

bifenox 6 10 DNOC 20 calcium dodecylbenzene sulfonate 3 ethoxylated alkyl phenol 3 cyclohexanone 25 heavy aromatic naphtha up to 100

EXAMPLE XV

bifenox 20 dinoterb 10 alkylarylsulfonate 2 alkylphenoxypolyoxyethylene-20 ethanols 4 isophorone 30 orthochlorotoluene to 100

EXAMPLE XVI

bifenox 15 25 dinoseb 15 amine salt of dodecylbenzenesulfonic acid 4 polyoxyethylene triglyceride 3 isophorone 20 30 heavy aromatic naphtha up to 100

EXAMPLE XVII

bifenox 20 3,6-DCP 4 calcium dodecylbenzene sulfonate 4 35 ethoxylated alkyl phenol * 4 isophorone 30 heavy aromatic naphtha up to 100 79 ö S Ö 9 9 A. "- ^ - 12 -tr EXAMPLE XVIII wt.% bifenox 15 2,4-DB ( isopropyl ester) 30 alkylaryisulfohate 4 5 polyoxyethylene triglyceride 2 cyclohexanone 25 xylene to 100

EXAMPLE XIX

bifenox 15 10 dichloroprop (butyl ester) 45 amine salt of dodecylbenzene sulfonate 3 alkylphenoxypolyoxyethylene ethanols 3 15 cyclohexanone 25 heavy aromatic naphtha to 100

EXAMPLE XX

bifenox 20 ioxynil (octanoate) 1.5 20 bromoxynil (octanoate) 2 calcium dodecylbenzene sulfonate 3 alkylphenoxy polyoxyethylene ethanols 4 isophorone 30 25 orthochlorotoluene to 100

EXAMPLE XXI

bifenox 25 2,3,6-TBA (ester) 3 calcium dodecylbenzene sulfonate 3 30 ethoxylated alkyl phenol 3 isophorone 30 orthochlorotoluene to 100

EXAMPLE XXII

bifenox 20 35 dicamba 2 alkylarylsulphonate 4 alkylphenoxypolyoxyethylene-ethanols 2 7909099 - 13 & wt. % cyclohexanone 25 xylene to 100

The active ingredients were added to the appropriate solvent or solvents, with stirring and optionally with heating, to aid dissolution of the active materials. Then the surfactants were added. After dissolving, the solution was filtered to remove insoluble impurities.

EXAMPLES XXIII-XXVI

The following aqueous suspensions were prepared from the following ingredients.

EXAMPLE XXIII qew. %/full. % 15 bifenox 20 bentazone 20 alkylarylsulfonate 2 phosphate ester of an ethoxylated polyarylphenol neutralized with 20 triethanolamine 2 xanthan gum 0.2 silicone anti-foaming agent 0.1 formaldehyde 0.2 water to 100

25 EXAMPLE XXIV

bifenox 40 ioxynil (sodium salt) 4 ethoxylated nonylphenol 3 hydroxymethyl cellulose 2 30 * silicone anti-foaming agent 0.1 water to 100

EXAMPLE XXV

bifenox 35 bromoxynil (potassium salt) 3.5 35 ethoxylated nonylphenol 2.5 hydroxymethyl cellulose 1.7 silicone anti-foaming agent 0.1 water to 100 7909099 * Ȏ '- 14 - EXAMPLE XXVI w / v% bifenox 48 benazoline (potassium salt ) 8 sodium lauryl sulfate 3 5 attapulgite 1.5 silicone anti-foaming agent 0.15 water to 100

The herbicide components were mixed with surfactants and anti-foaming agent, followed by vigorous stirring in water to yield a crude aqueous suspension. This suspension was then wet milled to reduce the particles of the active ingredients to 0.5-20 µl. An aqueous suspension of the thickener or suspending agent (hydrated) was then added to this wet milled preparation.

The following Example XXVII focuses on the test method used to determine the effectiveness of the method and mixture according to the invention.

EXAMPLE XXVII - test method.

An appropriate amount of the mixture (eg.

one of the concentrates of Examples I-XXVI) was added to water in a microspray, which was then shaken to ensure a dispersion. The sprinkler was adjusted to spray at a pressure of about 2.72 atmospheres a volume equivalent to 200 liters per hectare. The sprinkler was equipped with a standard manifold (Allman No. 0), which had a fan-shaped beam.

The application took place after the emergence of both the crop and the weeds, with the crop size varying from the 3-leaf stage to the beginning of stem elongation for various applications. At the time of applying the subject herbicides, the weed size was also variable from the cotyledon stage to the small plant stage.

35 7909099

Claims (14)

Method for controlling weeds in cereal fields, characterized in that bifenox of formula 5 of the formula sheet and one or more other active components, e.g. (1) a benzoic acid herbicide, on the cereal fields after the crop has emerged which is dicamba or 2,3,6-TBA or a salt or an ester thereof, (2) a phenoxy acid herbicide which is dichloroprop or 2,4-DB or a salt or an ester thereof, (3) a dinitrophenol herbicide which is DNOC, 10 dinoterb or dinoseb or a salt or an ester thereof, (4) a benzone vibratory herbicide which is ioxynil or bromoxynil or a salt or an ester thereof, (5) benazoline or a salt or an ester thereof, (6) bentazone or (7) 3,6-DCP or a salt or an ester thereof. Method according to claim 1, characterized in that the bifenox is applied in an amount of 0.25-3.0 kg / ha. 3. Method according to claim 2, characterized in that the bifenox is applied in an amount of 0.5-1.5 kg / ha. Method according to claim 3, characterized in that the bifenox is applied in an amount of 0.5-0.75 kg / ha. 5. Method according to claims 1-4, characterized in that the benzoic acid herbicide is applied in an amount of 0.05-0.2 kg / ha, the phenoxy acid herbicide in an amount of 0.1-3.5 kg / ha, the dinitrophenol herbicide in an amount of 0.5-5.0 kg / ha, the benzonitrile bicide in an amount of 0.05-0.5 kg / ha, the benazoline 30 in an amount of 0.05-0.25 kg / ha, the bentazone in an amount of 0.1-1.5 kg / ha and the 3.6-DCP in an amount of 0.025-0.15 kg / ha. 6. Process according to claims 1-5, characterized in that the bifenox is applied in an amount of 0.5-0.75 kg / ha and the phenoxy acid herbicide in an amount of 1.5-3.0 kg. / ha. Process according to claims 1 to 5, characterized in that bifenox is applied together with ioxynil and bromoxynil 7902099-16. The method of claim 1, substantially as described above. Herbicide mixture in the form of a concentrate or a tank mixture, containing bifenox and one or more of the active ingredients (1) to (7), as defined in claim 1, together with one or more non-phytotoxic diluents or carriers. The herbicide mixture according to claim 9, wherein the weight ratio of bifenox to the benzoic acid herbicide is 60: 1 to 1: 1; the weight ratio of the bifenox to the phenoxyacid herbicide is 30: 1 to 1:15; the weight ratio of bifenox to the dinitrophenol herbicide is 6: 1 to 1:20; the weight ratio of bifenox to the benzoni-15 vibration herbicide is 60: 1 to 1: 2; the weight ratio of bifenox to benazoline is 60: 1 to 1: 1; the weight ratio of bifenox to bentazone is 6: 1 to 1: 6; while the weight ratio of bifenox to 3,6-DCP is 30: 1 to 3: 1. Herbicide according to claim 9 or 10, in the form of a concentrate, containing 15-85% by weight of the active ingredients. Herbicide according to claim 11, in the form of an emulsifiable concentrate, which is an aqueous suspension or a wettable powder. Herbicide according to claim 9, substantially as described above with respect to one of the precursor Examples I-XXVI. Herbicide according to claims 9-13, for use in the method according to any one of claims 1-8. 30 35 7909099, Ν / 2937δ-Κρ / θΐ Belongs to patent application t.n.v. Lilly Industries Limited, London, C-root Britain. FORMULA SHEET O II CH3O— C CL 02N - ^ ^ -O- ^ ^ -CL 7 f ö 9 0 91