Herbicidal mixtures of S-halobenzyl-N,N-dialkylthiolcarbamates and 3-lower alkyl-2,1,3-benzothiadiazinone-(4)-2,2-dioxides and salts thereof

Abstract

Herbicidal compositions embodying mixtures of S-halobenzyl-N,N-dialkylthiolcarbamates and 3-lower alkyl-2,1,3-benzothiadiazinone-(4)-2,2-dioxides and salts thereof in weight ratios of 1:5 to 5:1.

Description

The present invention relates to the control of unwanted plants in important agricultural crops with a herbicidal composition or by first treating the soil before emergence of the plants and subsequently treating the plants after emergence.

It is known that substituted thiolcarbamates, diphenyl ethers, acid amides, benzoic acid, carbamates, terephthalates and benzothiadiazinones have a herbicidal action. However, their action is poor.

I have now found a process for controlling the growth of unwanted plants wherein the plants are treated postemergence with a composition of

A. a compound of the formula ##EQU1## where R denotes bicycloheptyl, cyclohexyl or lower alkyl (methyl, propyl), R.sup.1 denotes lower alkyl, and R.sup.2 denotes lower alkyl, or allyl substituted by halogen, or benzyl substituted by halogen, B. a compound of the formula ##EQU2## where R denotes lower alkyl of a maximum of 4 carbon atoms, or its salts, such as alkali metal, alkaline earth metal, ammonium, hydroxyalkylammonium, alkylammonium and hydrazine salts, e.g., salts of sodium, lithium, potassium, calcium, iron, methylammonium, trimethylammonium, ethylammonium, diethanolammonium, ethanolammonium, dimethylamine, dimethylethanolamine, hydrazine or phenylhydrazine.

Active ingredients a, and b may be applied in amounts of from 0.5 to 5 kg/hectare. In the composition the weight ratio may vary from 1:5 to 5:1, particularly 1:3 to 3:1.

This process and the compositions of the invention destroy unwanted plants without damaging crop plants; they are therefore particularly suitable for controlling unwanted plants (dicotyledonous seed weeds, monocotyledonous grassy seed weeds, Cyperaceae) in crop plants (rice, ground-nuts, cotton, Indian corn, soybeans, peas, beans, potatoes, cereals, alfalfa, clover).

The active ingredients may be used as solutions, emulsions, suspensions, oil dispersions, granules or dusts. The form of application depends entirely on the purpose for which the agents are being used; in any case it should ensure a fine distribution of the active ingredient.

For the preparation of solutions to be sprayed direct, mineral oil fractions having a medium to high boiling point, such as kerosene and diesel oil, further coal-tar oils and oils of vegetable and animal origin, and cyclic hydrocarbons such as tetrahydronaphthalene and alkylated naphthalenes are suitable.

Aqueous formulations may be prepared from emulsion concentrates, pastes or wettable powders by adding water. To prepare emulsions the ingredients as such or dissolved in a solvent may be homogenized in water or organic solvents by means of wetting or dispersing agents, e.g., polyethylene oxide adducts. Concentrates which are suitable for dilution with water may be prepared from active ingredient, wetting agent, adherent, emusifying or dispersing agent and possibly solvent. Oils of various types may be added to ready-to-use spray liquors.

Dusts may be prepared by mixing or grinding the active ingredients with a solid carrier, e.g., kieselguhr, talc, clay or fertilizers.

Granules may be prepared by bonding the active ingredients with solid carriers.

Oils may be used to produce directly sprayable dispersions.

The new compounds may be mixed with fertilizers, insecticides, fungicides or herbicides.

EXAMPLE 1

An agricultural plot was sown with rice (Oryza sativa), barnyard grass (Echinochloa crus-galli), yellow nutsedge (Cyperus esculentus) and waterplantain (Alisma plantago-aquatica). Treatment with the active ingredients:

I 4'-nitro-2,4-dichlorodiphenyl ether, 2 kg per hectare; Ii 4'-nitro-2,4,6-trichlorodiphenyl ether, 2 kg per hectare; Iii 2,4'-dinitro-4-trifluoromethyldiphenyl ether, 2 kg per hectare; Iv s-(4-chlorobenzyl)-N,N-diethylthiolcarbamate, 0.25, 0.75 and 3 kg per hectare; V o,s-dimethyltetrachlorothioterephthalate, 2 kg per hectare; Vi methyl-2,3,5,6-tetrachloro-N-methoxy-N-methylterephthalamate, 3 kg per hectare; Vii 3-isopropyl-2,1,3-benzothiadiazinone-(4)-2,2-dioxide, 0.25, 0.5, 0.75, 1.0 and 1.5 kg per hectare; Viii 2,4-dichloro-4'-nitro-3'-methoxydiphenyl ether, 0.25, 0.5, 0.75 and 1.0 kg per hectare; Ix 3-(2-methylphenoxy)-pyridazine, 0.25, 0.5, 0.75 and 1.0 kg per hectare; X 2,5-dichloro-6-fluorophenyl-4-nitrophenyl ether,

0.25, 0.5, 0.75 and 1.0 kg per hectare, each active ingredient being dispersed in 500 liters of water per hectare, was carried out as follows:

A with I, II, III, IV, V, VI and VII before or shortly after sowing; B with I, II, III, IV, V, VI and VII after emergence of the weeds; C with I, II, III, IV, V and VI before or after sowing combined with VII applied after emergence of the weeds; D with the compositions IV+VII, VII+VIII, VII+IX and VII+X of the broadleaved and grassy weeds in the early (0 to 2nd) leaf stage.

The results obtained with these 4 treatment methods are given below:

Method__________________________________________________________________________ A BActive ingredient I II III IV V VI VII I II III IV V VI VII__________________________________________________________________________Oryza sativa 10 0 10 5 5 5 0 40 10 10 5 20 20 0Echinochloacrus-galli 80 80 95 100 95 100 0 80 80 80 40 55 90 5Cyperus esculentus 10 0 40 0 0 20 0 40 40 60 10 0 10 85Alisma plantago-aquatica 10 10 25 30 5 45 5 40 20 35 5 10 50 90__________________________________________________________________________ CActive ingredient I+VIII II+VIII III+VIII IV+VIII V+VIII VI+VIII__________________________________________________________________________Oryza sativa 10 0 10 5 5 5Echinochloa crus-galli 90 90 100 100 100 100Cyperus esculentus 95 95 100 85 85 100Alisma plantago-aqua-tica 100 100 100 100 100 100__________________________________________________________________________ DActive ingredient IV VII VIIkg/ha 0.75 0.25 0.75 0.25 0.5 1.0__________________________________________________________________________Oryza sativa 5 0 0 0 0 0Echinochloa crus-galli 65 45 8 0 6 15Cyperus esculentus 20 5 65 50 60 70Cyperus rotundus 10 5 60 45 50 70Scirpus maritimus 20 10 60 40 50 70Scirpus mucronatus 25 10 65 50 55 70Alisma plantago-aquatica 15 5 50 35 40 60Butomus umbellatus 5 0 60 40 45 65Ammannia coccinea 15 5 55 40 50 60Ammannia auriculata 10 5 60 45 50 65__________________________________________________________________________Active ingredient VIIIkg/ha 0.25 0.5 0.75 1__________________________________________________________________________Oryza sativa 5 7 8 10Echinochloa crus-galli 40 45 55 60Cyperus esculentus 10 20 25 35Cyperus rotundus 10 15 20 25Scirpus maritimus 10 20 30 45Scirpus mucronatus 5 15 30 40Alisma plantago-aqua tica 10 15 20 30Butomus umbellatus 5 8 10 15Ammannia coccinea 10 12 15 20Ammannia auriculata 0 5 5 8__________________________________________________________________________Active ingredient IXkg/ha 0.25 0.5 0.75 1__________________________________________________________________________Oryza sativa 0 5 10 12Echinochloa crus-galli 40 50 55 60Cyperus esculentus 15 25 30 45Cyperus rotundus 10 12 15 20Scirpus maritimus 15 20 25 40Scirpus mucronatus 5 15 20 30Alisma plantago-aquatica 15 20 25 40Butomus umbellatus 10 12 15 25Ammannia coccinea 10 12 15 20Ammannia auriculata 10 12 15 20__________________________________________________________________________Active ingredient X IV+VIIkg/ha 0.25 0.5 0.75 1 0.75+0.25 0.25+0.25 0.25+0.75__________________________________________________________________________Oryza sativa 0 4 5 8 5 0 0Echinochloa crus-galli 35 40 60 65 80 60 70Cyperus esculentus 5 15 20 30 80 65 85Cyperus rotundus 5 8 10 15 75 65 80Scirpus maritimus 5 10 15 20 80 60 85Scirpus mucronatus 10 15 20 30 85 70 90Alisma plantago-aquatica 10 15 20 30 55 45 70Butomus umbellatus 5 8 10 15 50 45 55Ammannia coccinea 5 10 15 20 70 55 80Ammannia auriculata 0 5 10 15 70 60 85__________________________________________________________________________Active Ingredient VII+VIIIkg/ha 0.25+0.75 0.25+0.25 0.75+0.25__________________________________________________________________________Oryza sativa 8 5 5Echinochloa crus-galli 85 55 75Cyperus esculentus 80 70 85Cyperus rotundus 80 70 85Scirpus maritimus 75 65 85Scirpus mucronatus 85 75 75Alisma plantago-aquatica 65 55 75Butomus umbellatus 70 65 80Ammannia coccinea 60 65 85Ammannia auriculata 70 65 70__________________________________________________________________________Active ingredient VII+IXkg/ha 0.25+0.75 0.25+0.25 0.75+0.25__________________________________________________________________________Oryza sativa 10 0 0Echinochloa crus-galli 70 55 65Cyperus esculentus 85 70 90Cyperus rotundus 70 70 90Scirpus maritimus 85 70 80Scirpus mucronatus 85 70 80Alisma plantago-aquatica 70 60 80Butomus umbellatus 70 65 75Ammannia coccinea 65 60 75Ammannia auriculata 70 60 80__________________________________________________________________________Active ingredient VII+Xkg/ha 0.25+0.75 0.25+0.25 0.75+0.25__________________________________________________________________________Oryza sative 5 0 0Echinochloa crus-galli 75 45 70Cyperus esculentus 80 65 85Cyperus rotundus 70 60 80Scirpus maritimus 70 50 80Scirpus mucronatos 85 65 95Alisma plantago-aquatica 70 60 85Butomus umbellatus 65 50 70Ammannia coccinea 60 50 65Ammannia auriculata 70 55 80__________________________________________________________________________ 0 = no damage100 = complete destruction

The following compositions provide the same good action:

O,o-dimethyl-2,3,5,6-tetrachloroterephthalate, 2,3,5-trichloropyridinol-(4), 2,4-dichloro-4'-cyanodiphenyl ether, 2,4,6-trichloro-4'-cyanodiphenyl ether, 3-chloro-4-fluoro-4'-nitrodiphenyl ether, 3-chloro-4-bromo-4'-nitrodiphenyl ether, 3-chloro-4-methyl-4'-nitrodiphenyl ether, 3-chloro-2-fluoro-4'-nitrodiphenyl ether, 3-bromo-2-fluoro-4'-nitrodiphenyl ether, 2,4-dichloro-4'-nitrodiphenyl ether, 2,4-dibromo-4'-nitrodiphenyl ether, 2,4-dichloro-4'-nitro-3'-methoxydiphenyl ether, 2-phenoxypyridazine, 3-(2-ethylphenoxy)-pyridazine, 3-(2-propylphenoxy)-pyridazine, 3-(2-isopropylphenoxy)-pyridazine, 3-(2-sec-butylphenoxy)-pyridazine, 3-(2-tert-butylphenoxy)-pyridazine, 6-chloro-3-[2-(propenyl)-phenoxy]-pyridazine, 6-chloro3-[2-(2-methyl)-phenoxy]-pyridazine, 3-[2-(2-propyl)-phenoxy]-pyridazine, 3-(2-methyl-5-isopropylphenoxy)-pyridazine, 3-(2-isopropyl-5-methylphenoxy)-pyridazine, 3-(2-sec-butyl-5-methylphenoxy)-pyridazine, 3-(2-methyl-4-tert-butylphenoxy)-pyridazine, 3-phenoxypyridazine, 3-(2-methylphenoxy)-pyridazine, 3-(2,5-dimethylphenoxy)-pyridazine, 3-phenylthiopyridazine, 3-(2-methylphenylthio)-pyridazine, 3-(2-methylphenylthio)-6-methylpyridazine, 3-methyl-6-(2-methylphenylthio)-pyridazine, 3-(2-methyl-4-chlorophenylthio)-pyridazine, 3-(4-tert-butylphenylthio)-pyridazine 3-methyl-6-(2,4-dimethylphenylthio)-pyridazine, 3-(2,4-dichlorophenylthio)-pyridazine, 3-isopropyl-2,1,3.sup.+-benzothiadiazinone-(4)-2,2-dioxide.

Claims

1. A process for controlling the growth of unwanted plants which comprises treating said plants postemergence with a herbicidally effective amount of

a. a compound of the formula ##EQU3## wherein R and R.sup.1 each denote lower alkyl and R.sup.2 denotes benzyl substituted by halogen, and

b. a compound of the formula ##EQU4## wherein R' denotes lower alkyl of a maximum of four carbon atoms or an alkali metal, alkaline earth metal, ammonium, lower alkylammonium, lower hydroxylalkylammonium, or hydrazine salt thereof, the weight ratio of a to b being in the range of 1:3 to 3:1.

2. A process as claimed in claim 1 wherein compound a is S-(4-chlorobenzyl)-N,N-diethylthiolcarbamate.

3. A process as claimed in claim 1 wherein compound a is S-(4-chlorobenzyl)-N,N-diethylthiolcarbamate, and R in compound b is isopropyl.