CA2052869A1

CA2052869A1 - Synergistic herbicidal compositions

Info

Publication number: CA2052869A1
Application number: CA002052869A
Authority: CA
Inventors: Erwin Hacker; Hermann Stubler; Klaus Bauer; Hermann Bieringer; Heinz Kehne
Original assignee: Individual
Current assignee: Hoechst AG
Priority date: 1990-10-08
Filing date: 1991-10-07
Publication date: 1992-04-09
Also published as: KR920007534A; KR100240568B1; DK0480306T3; ATE126965T1; JP3084102B2; EP0480306B1; ZA917996B; JPH04257505A; AU8557291A; CN1046183C; CN1060386A; EP0480306A1; AU643074B2; DE59106361D1; BR9104317A; ES2079542T3

Abstract

ABSTRACT OF THE DISCLOSURE

Synergistic herbicidal compositions Compositions of a combination of A) compounds of the formula (I) or salts thereof

Description

20~2~6~

HOECHST AKTIENGESEIISCEI~FT ~OE 90/F 304 Dr. WE/AP

Description .

Synergistic herbicidal composition~

The invention is in the field of the crop protection agents which can be used against monocotyledon ~nd dicotyledon weeds.

~P-A-0, 342, 569, EP-A-0, 342, 568 and EP-A-0,388,771 des-cribe heterocyclically substituted phenoxysulfonylureas by means of which a broad range of mono- and dicotyledon weeds can be controlled. They can be employed both as a soil-acting herbicide and via the leaves and also show a particularly high selectivity in monocotyledon crop plants such as cereals, corn and sorghum, but al~o in rice, in particular in paddy rice.

However, a ~eries of economically highly important monocotyledon weeds, for example Cyperus rotundus, Cyperus e~culentus, Cyperus serotinus, Eleooharis kuroguwai and many others, exist in rice and in other crops, and these weeds cannot be controlled in an optimal fashion using the abovementioned compounds on their own.

Surprisingly, some herbicidal active substances have now been found which, when used in conjunction with the abovementioned compounds, have pronounced synergistic properties as regards the effectivity against we2ds.

The present invention relates to herbicidal compositions with an effective content of A) compounds of the formula (I) or salts thereof ( R 2 ) ,~ S 2 N H--C--N--~(~ ; ( I ) 2~52~69 in which al) R1 is ethoxy, propoxy or isopropoxy and R2 is halogen, N02, CF3, CN, C1-C4-alkyl, Cl-C4-alkoxy, Cl-C4-alkylthio or (C1-C4-alkoxy)-carbonyl and n is 0, 1, 2 or 3, or a2) Rl is optionally unsaturated C~-C8~alkoxy which i~
substituted by halogen, optionally unsaturated Cl-C6~alkoxy, a radical of the formula (Cl-C~-alkyl)-S-, ~Cl-C5-alkyl)-S0-, ~Cl-C6-alkyl)-S02-, (C1-C6-alkyl)-0-CO-, NO2, C~ or phenyl; further-more C2-C8-alkenyloxy or -alkynyloxy and R2 is saturated or unsaturated C1-C~-alkyl, phenyl, phenoxy, C1-C4-alkoxy, C1-C4-alkylthio, (C1-C4-alkoxy)-carbonyl, it ~eing possible for all the above R2 radicals to be ~ubstituted by halogen, C1-C4-alkoxy or Cl-C4-alkylthio, or is halogen, N02, Cl-C4-alkylstllfonyl or -sulfinyl, and n is 0, 1, 2 or 3, or a3) R1 is Cl-C~-alkoxy and R2 is C2-C~-alkenyl or -alkynyl, phenyl or phenoxy, the abovementioned R2 radicals being unsubsti-tuted or substituted by halogen, C1~C4-alkoxy or -alkylthio, or is C1-C4-alkylsulfonyl or -alkyl-sulfinyl and n is 1, 2 or 3, or a4) R1 - in each case in the 2-position on the phenyl radical - is halogen, methoxy, ethyl or propyl, R2 is (C1-C4-alkoxy)-carbonyl in the 6-position on the phenyl radical and n is 1, and, in all cases a1)-a4), R3 is hydrogen, saturated or unsaturated C1-C~-alkyl or Cl-C4-alkoxy, - ~0~6~

R4 and R5 indep~ndently of one another are hydrogen, halogen, C1-C4-alkyl, Cl-C4 alkoxy, C1-C4-alkylthio, the three last-mentioned radicals being unsu~sti-tuted or substituted b~ halogen, Cl-C~4-alkoxy or 5Cl-C4-alkylthio, Y is O or S and E is CH or N, in combination with B) one or more compound(s) from the group comprising the compounds B1) pyrazosulfuron-ethyl (NC 311) of the formula I ~, f 50~-NH-CO-NH ~ ~ ~ B1) B2) bensulfuron-methyl of the formula CH25O2NHCOI~H ~ ~ (B2) B3) amidosulfuron of the formula ~3~52 1~(cH3)-so2-NH-co-NH ~ ~ (B3) B4) imazosulfuron (T~ 913) of the formula ~ 502-NH-CO-NH- ~ (B~) B5) dimetrasulfuron (cinosulfuron) of the formula H3Co ~ ~ NH-CO-NH 502 ~ (B5) 2~8~9 and B6) metsulfuron-methyl (DPX-T 6376) of the formula ~ 5O2-NH-CO-NH-~ ~ (B6) The compounds A (compounds of ~he fo~mula I) are dis-closed in the German pat~nt app:Lications mentioned at theoutset.

The compound pyrazosulfuron-ethyl is known from Japan Pesticide Information No. 55 (1989), pages 17 to 20, and from "Farm Chemicals Handbook '90", Meister Publishing Company, Willoughby, Ohio, USA.

Bensulfuron-methyl is known from publications by G.S. Peudpaichit et al. as DPX-F 5384 in Asian-Pacifis Weed Science Society, pages 114 to 122, and by S. Tokeda et al. (ibid. pages 156 to 161) and in the abovementioned ~'Farm Chemicals Handbook '90".

Amidosulfuron is known from E. Hacker et al. in Z. Pfl.
Krankh. Pfl.Schutz, Sonderh. XII [Special Issue], pages 489 to 497 (1990), as HOE 75032.

Imazosulfuron ~TH 913) is di~closed in EP-A-0,238,070.

Dimetrasulfuron (cinosulfuron) is known from Briti~h Crop Prot. Conf. (Weeds) 1987.

Metsulfuron-methyl is described in "The Pesticide Manual", British Crop Protection Council, Bth ed., page 575.

Herbicidal compositions according to the invention with compounds of the abovementioned formula (I) or salts thereof which are of pa:rticular interest are those in which 2~28~9 a1) R1 is ethoxy, propoxy or isopropoxy and R2 i5 in the 6-position and has the abovementioned meaning, and n is O or 1, or a2) R1 is optionally unsaturated C1~C4-alkoxy which is substituted by halogen, C1-C4-alkoxy, Cl-C4-alkylthio or -sulfinyl or -sul fonyl, ( Cl-C4 alkoxy)-carbonyl, NO2, CN or phenyl; furthermore C2-C5-alkenyloxy or C2--C4-alkynyloxy, and R2 is Cl-C4-alkyl, C2-C5-alkenyl, (Cl-C4-alkoxy)-carbonyl, Cl-C4-alkoxy or Cl-C~-alkylthio, each of which can be substituted as indicated above, or is halogen, and n is O or 1, or a3) R1 is methoxy, ethyl or propyl and R2 is 6-methoxycarbonyl or 6-ethoxycarbonyl and n is 1, and in all cases al) - a3), R3 is hydrogen, Cl-C4-alkyl, in particular hydrogen or methyl, R4 and R5 are halogen, Cl-C4-alkyl, Cl-C4-alkoxy or Cl-C4-alkylthio, the 3 last-mentioned radicals being unsubstituted or substituted by halogen, Cl-C4-alkoxy or C1-C4-alkylthio, Y is O or S, in particular 0, and E is C~ or N, in particular C~.

Analogously, saturatad or unsaturated al.kyl and alkoxy are straight-chain or branched alkyl or ~lkoxy; halogen is F, Cl, Br and I, preferably F and Cl.

The compounds of the formula (I) can form salts in which - 6 - 2~2~9 the hydrogen of the So2-NH- group is xeplaced by a cation suitable for agriculture. ~hese salt~ are generally metal salts, in particular alkali metal salts, alkaline earth metal salts, optionally alkylated ammonium salts or salts of other organic amines.

The stereochemistry of the abotrementioned formulae of the compounds A and B was not ind:icated in detail. If it is possible for stereoisomers to occur, the formulae also embrace all geometric isomers, enantiomers and dia-stereomers, and their mixtures.

Preferred herbicidal compositions contain, as compoundsA, one or more compounds of the formulae Al, A2 and A3, the formulae having the following meanings:

~OC2~l:, N OCH3 (~ OS 2--NH- C O- N1~

~OCH ( C~3 )2 N OCH3 ~0502--t`lH CC) NH (N(~ ~ F12 ) ,OCH3 N OCH3 (~j~ 5 2--l~l H C O (N(~ ( 2 3 ) \C"--OCH3 OCH3 The herbicidal compositions according to the invention have an excellent herbicidal activity against a broad range of economically important monocotyledon and dicoty-ledon harmful plants. The active substance combinationsalso act efficiently on perennial weeds which produce shoots from rhizomes, rootstocks or other perennial organs and which are difficult to control. In this context, it does not matter whether the æubstances are applied pre ~eeding, pre-emergence or post-emergence.
Specifically, examples may be mentioned of some 7 ~2~6~

representatives of the monocotyledon and dicotyledon weed flora which can ~e controlled by the compo~itions according to the invention, without the enumeration being a restriction to certain specie3.

Examples of monocotyledon weed species on which the compositions act efficiently are Echinochloa, Digitaria, Setaria and also Cyperus species, and also perennial Cyperus species.

In the case of the dicotyledon weed species, the range of action extends to Galium, Viola, Veronica, Lamium, Cnenopodi~n, Stellaria, Amaranthus, Sinapis, Ipomoea, Matricaria, Polygon~n, Abutilon and Sida from amongst the annuals, and inter alia, Convolvulus, Cirsi~n, Rumex and Artemisia in the case of the perennial weeds.

The active substance combinations according to the invention likewise effect outstanding control of mono-cotyledon and dicotyledon weeds which occur under the specific conditions of rice growing, such as, for example, Sagittaria, Alisma, Eleocharis, Scirpus, Cyperus and others.

If the herbicidal compositions according to the invention are applied to the soil surface before germination or are broadcast, or poured, into the flooded paddy field, then the weed seedlings are either prevented completely from emerging, or the weeds grow until they have reached the cotyledon stage but then their growth ~tops, and, even-tually, after three to four wee~s have elapsed, they die completely.

If the active substance combinations are applied post-emergence on the green parts of the plants or to the flooded paddy field, growth also stops drastically a very short time after the treatment and the weed plants remain at the growth stage at the time of application, or after a certain time they completely die more or le 8 rapidly, ~ 8 - 2~ Q~;~
so that in this manner competition by the weeds, which is harmful to the crop plants, can be eliminated at a very early point in time and in a sustained manner by using the novel compositions according to the invention.

Even though the compositions according to the invention have an excellent herbicidal activity against mono-cotyledon and dicotyledon weeds, crop plants of economically important crops, such as, for example, wheat, barley, corn and~or rice, are damaged not at all, or only to a negligible extent. For these reasons, the compositions are highly suitable for selectively controlling undesired plant growth in plantings for agricultural use.

For example, the active ~ubstance combinations according to the invention allow a herbicidal action to be achieved which exceeds what would have been expected as the additive action of the individual components. Such increases in action permit the dosage ra1:es of the indiviclual active substances to be reduced substantially.
There have also been found advantageous effe~ts of such a nature that either the long-time action of the combina-tions i8 improved or that the speed of action is found to have increased. Such properties are therefore novel inventions economically progressive which have considerable advantages for the user in practical weed control since he can control weeds more cost-effectively or more rapidly or in a more sustained manner, which allows higher yields to be harvested in the crop plant stand.

Furthermore, it has been found that ~ number of the active substance combinations exhibit a pronounced safener or antidote action, i.e. phytotoxic side-effects in crop plants, for example rice, which are caused by the active substances used are reduced or avoided completely.

3~ The mixing ratios A : B can vary within wide limits and 9 2~5~8~

are generally be~ween 1 : 0.1 to 1 : 10. The mîxing ratio is selected as a function of, for example, the mixture components, the development stage of the weeds, the weed spectrum and the prevailing climatic conditions.

It is preferred to use miximg ratios from 1 : 0.25 to 1 : 4. The application rates of herbicide A in the active substance mixtures are prefera]bly between 5 and 50 g/ha, the application rates of B between 5 g and 200 g/ha.

The active substance combinations according to the invention can exist in the form of mixed formulations of the two components which are then diluted with water and applied in the customary fashion, or they can be prepared in the form of so-called tank mixes by con~oint dilution of the separately formulated components with water.

The compounds A and B or the combinations thereof can be formulated in a variety of ways, as predetermined by the biological and/or physicochemical parameters. The following possibilities, for example, are suitable for formulation: wettable powders (WP), emulsifiable con-centrates (EC), aqueous solutions (SL), emulsions (EW) such as oil-in-water and water-in-oil emulsions, spray-able solutions or emulsions, dispersions on an oil or water base, suspo-emulsions, dusts (DP), seed-dressing agents, granules for soil application or for broadcasting or water-dispersible granules (WG), ULV formulations, microcapsules or waxes.

These individual formulation types are known in principle and are described, for example, in: Winnacker-Kuchler, ~Chemische Technologie" [Chemical Technology], Volume 7, C. Hauser Verlag Munich, 4th Ed. 1986; van Valkenburg, ~Pesticides Formulations", Marcel Dekker N.Y., 2nd Ed.
1972-73; K. Martens, "Spray Drying Handbook", 3rd Ed.
1979, ~. Goodwin Ltd. London.

The formulation auxiliaries required, such as inert materials, surfactants, solvents and other additives, are lo 2~2~6~
also known and are described, for example, in: Watkins, "Handbook of Insecticide Dust Diluents ancl Carriers", 2nd Ed., Darland Books, Cal~well N.J.; H.v.Olphen, "Introduction to Clay Colloid Chemistry", 2nd Ed., J.
Wiley h Sons, N.Y.; Marsden, "Solvents Guide", 2nd Ed., Interscience, N.Y. 1950; ~cCutcheon's, "Detergents and Emulsifier-~ Annual", MC Publ. Corp., Ridgewood N.J.;
Sisley and Wood, ~Encyclopedia of Surface Active Agents", Chem. Publ. Co. Inc., N.Y. 19~4; Schonfeldt, ~Grenz-flachenaktive Athylenoxidaddukte" [Surface-active Ethylene Oxide Adducts]", Wiss. Verlagsgesell., Stuttgart 1976; Winnacker-Kuchler, "Chemische Technologie"
[Chemical Technology], Volume 7, C. Hauser Verlag Munich, 4th Ed. 1986.

Combinations with other pesticidally active substances, such as other herbicides, fungicides or insecticides, and with fertilizers and/or growth regulators may also be prepared on the basis of these formulations, for example in the form of a readymix formulation or as a tank mix.

Wettable powders are preparations which are uniformly dispersible in water and which, besides the active substance, also contain wetting agents, for example polyoxethylated alkylphenols, polyoxethylated fatty alcohols or fatty amines, alkane- or alkylbenzenesulfon-ates, and dispersing agents, for example sodium lignin-sulfonate, sodium 2,2'-dinaphthylmethane-6,6'-di-sulfonate, sodium dibutylnaphthalenesulfonate~ or alter-natively sodium oleylmethyltaurinate, in addition to a diluent or inert ubstance.

Emulsifiable concentrates are prepared by dissolving the active substance in an organic solvent, for example butanol, cyclohexanone, dimethylformamide, xylene and also higher-boiling aromatic compounds or hydrocarbons, with the addition of one or more emulsifiers.
Examples of emulsifiers which can be used are:
calcium salts of an alkylarylsulfonic ~cid, such as Ca 2~2~

dodecylbenzenesulfonate, or non-ionic emulsifiers, such as fatty acid polyglycol ester~, alkylaryl polyglycol ethers, fatty alcohol polyglycol ethers, propylene oxide/ethylene oxide conden~ation products, alkyl poly-ethers, sorbitan fatty acicl e~ters, polyoxyethylenesorbitan fatty acid esters or polyoxyethylene sorbitol esters.

Dusts can be obtained by grinding the active substance with finely divided solid substances, for example talc or natural clays, such as kaolin, bentonite, pyrophyllite or diatomaceous earth.

Granules can be produced either by spraying the active substance onto adsorptive, granulated inert material or by applying active substance concentrates onto the surface oE carriers, such as sand, kaolinites or granu-lated inert material, by means of binders, for example polyvinyl alcohol, sodium polyacrylate or, alternatively, mineral oils. Suitable active substances can also be granulated in the manner which is conventional for the productiGn of fertilizer granules, if desired in a mixture with fertilizers.

The agrochemical preparations generally contain 0.1 to 99 percent by weight, in particular 2 to 95% by weight, of active substances A + B. The concentrations of the active substances A ~ B can vary in the formulations.

The concentration of active substance in wettable powders is, for example, about 10 to 95~ by weight; the remainder to 100% by wleight is composed of conventional formulation components. In the case of emulsifiable concentrates, the concentration of active substance can be about 1 to 85~
by weight, preferably 5 to 80% by weight. Formulations in the form of dusts contain about 1 to 25% by weight, usually 5 to 20~ by weight of active substance, sprayable solutions about 0.2 to 25% by weight, preferably 2 to 20%
by weight o:E active substance. In the case of granules - 12 - 2~
such as water-dispersible granules, the active substance content depends partly on whether the active compound is liquid or solid and on which granulation auxiliaries and fillers are used. As a rule, t:he content in the case of the water-dispersible granulesl is between 10 and 90~ by weight.

In addition, the active substance formulations mentioned contain, if appropriate, the adhesives, wetting agents, dispersing agents, emulsifiers, penetrant~, solvents, fillers or carriers which are conventional in each ~ase.

For use, the formulations, present in commercially available form, are diluted, if appropriate, in a customary manner, for example using water in the case of wettable powders, emulsifiable concentrates, di~persions and water-di persible granules. Preparations in the form of dusts or granules for soil application or for broad-casting and also sprayable solutions are usually not further diluted with other inert substances before u3e.

The application rate required for the compound~ of the formula (I) varies with the external conditions, such as, inter alia, temperature, humidity and the nature of the herbicide used.

The examples which follow serve to illustrate the inven-tion:
A. Formulation Examples a) A du~t is obtained by mixing 10 parts by weight of an active substance combin tion according to the invention and 90 parts by weight of talc as inert substance and comminuting the mixture in a hammer mill.

b) A wettable powder which is readily dispersible in water is obtained by mixing 25 parts by weight of - 13 - 2~28~
active su~stance A + B, ~4 parts by weight of kaolin-containing quartz as the inert substance, 10 parts by weight of pota~ium ligninsulfonate and 1 part by weight of ~odium oleoylmethyltaurinate as the wetting and dispersing agent, and grinding the mixture in a pinned disk mill.

c) A dispersion concentrate which is readily dispers-ible in water is obtained by mixing 20 parts by weight of active ~ubstance A ~ B with 6 parts hy weight of alkylphenol polyglycol ether (0Triton X
207), 3 parts by weight of isotridecanol polyglycol ether (8 EO) and 71 paxt3 by weight of paraffinic mineral oil (boiling range, for example, about 255 to above 277C), and grinding the mixture in a ball mill to a fineness of below 5 microns.

d) An emulsifiable concentrate is obtained from 15 parts by weight of active substance A ~ B, 75 parts by weight of cyclohexanone as the solvent and 10 parts by weiqht of oxethylated nonylphenol as the emulsifier.
e) Water-dispersible granuies are obtained by mixing 75 parts by weight of active substances A + B, 10 " calcium ligninsulfonate, 5 " sodium lauryl sulfate, 3 ' polyvinyl alcohol and 7 " kaolin, grinding the mixture on a pinned disk mill, and granulating the powder in a fluidized bed by spray-ing on water as the granulation liquid.

f) Water-dispersible granules are also obtained by homogenizing and precomminuting, on a colloid mill, - 14 - 2~2Q~
25 parts by weight of active substances A + B, 5 '` sodium 2,2'-dinaphthyl-methane-6,6'-disulfonate, 2 " sodium oleoylmethyltaurinate, 1 part by weight of polyvinyl alchol, 17 parts by weight of calcium carbonate and 50 " water, subsequsntly grinding the mixture on a bead mill, and atomizing and drying t]he resulting suspension in a spray tower by means of a single-compound nozzleO

For example, the active substance combin,ation~ in Table 1 below are formulated in the formulat:ions described under a) to f):

- 15 ~ 28~.~
Table 1 Active substance A Active substance B Ratio . . .
Al B1 1: 1 1: 2 A1 B2 1: 1 1: 2 1: 3 Al B3 1: 1 1: 2 1: 4 A1 B4 1: 1 1: 2 1: 4 Al B5 1: 1 1: ~
1: 4 A1 B6 1: 1 1: 2 1: 4 Biological Examples 1. Pre-emergence action on weeds Seeds or rhizome pieces of mono- and dicotyledon w~ed plants are placed in plastic pots of diameter 9 cm which 25 contain sandy loam soil, and covered with 80il. We2ds which occur in rice cultivation are grown in water-saturated soi.l, the pots being filled with such an amount of water that the water reaches the soil surface or floods it to a depth of some millimeters. The active substance combinations according to the invention which 2~2~6~

are formulated as wettable powders or emulsion concen-trates and, in parallel experiments, the suitably formu-lated individual active substclnces, are then applied to the surface of the soil cover in the form of aqueous suspensions or emulsions at an application rate of 600 to 800 l of water/ha (converted) r in various dosages or in the case of rice poured into the irrigation water.

After the treatment, the pots are placed in the green~
house and kept under good growth conditions for the weeds. After the test plants have emerged, the damage to the plants or the negative effect on the emergence is scored visually after a test period of 3 to 4 weeks by comparison with untreated controls. The herbicidal compositions according to the invention have a good herbicidal pre-emergence ~ctivity against a broad range of grass weeds and broad-leaved weeds.

The active substance combinations according to the invention have a herbicidal action which is higher than would have been expected based on the effects which were observed when the individual components were applied on their own. The active substance combinations are there-fore synergistic.

2. Post-emergence action on weeds Seeds or rhizome pieces of mono- and dicotyledon weeds 2~ are placed in sandy loam soil in plastic pots, covered with soil and grown in a greenhouse undPr good growth conditions. Weeds which occur in rice cultivation are grown in pots which are flooded with water up to a depth of 2 cm above the soil surface, and cultured during the test period. Three weeks after sowing, the test plants are treated in the three-leaf stage.

The active substance combinations according to the invention which are formulated as wettable powders or emulsion concentrates, and, in parallel tests, the - 17 _ 2~
suitably formulated individual active substances, are sprayed onto the green parts of the plants at an appli-cation rate of 300 to ~00 l of water/ha (converted)l in various dosages, and, after thle test plants had remained in the greenhouse for about 3 to 4 weeks under ideal growth conditions, the effect of the preparations was scored visually by comparison with untreated controls. In the case of those weeds which occur in rice cultivation, the active substances are also placed directly into the irrigation water (application analogously to the so-called granule application) or sprayed onto plants and into the irrigation water. In post-emergence, too, the compositions according to the invention havs a good herbicidal activity against a broad range of economically important grass weeds and broad-leaved weeds. The actions of the compositions according to the invention are synergistic.

3. Crop plant compatibility In further greenhouse experiments, seeds of a substantial number of crop plants and weeds are placed in sandy loam soil and covered with soil. Rice is grown and cultured in water-saturated soil as paddy rice.

Some of the pots ara treated immediately as described under l., and the remaining pots are placed in the greenhouse until the plants have developed two to three true leaves and then sprayed with the active substance combinations according to the invention and, for com-parison, only with an individual active substance in various dosages, as described under 2. In the case of paddy rice the application can also take place partially by pouring the active cubstances or a formulation thereof into the irrigation water.

Visual scoring four to five weeks after the application and after thle plants had been in the greenhou~e reveals that pre- and post-emergence treatments with the active 2 ~ ~ ~

substance combinations according to the invention do not inflict any damage to variou~ crops, even when high dosages of active substance are used. They leave Gramineae crops, for example lwheat and rice, unharmed.
The active substance combinations according to the invention therefore have a high selectivity when used for controlling undesirable plant growth in agricultural crops.

Compared with the use of the individual active substances on their own, it becomes obvious that the selectivity of the active substance combinations compared with equal application rates of the individual active substances is better than the most effective of each of the herbicides~
in particular in the case of higher dosage rates. The active substance combinations are therefore suitable for effectively reducing herbicide damage to crop plants.

4. Biological field trial In a field trial with plots of size 0.8 m2, rice in the 2-leaf stage was planted at a depth of 2 cm. Weeds were additionally seeded in or planted. When Echinochloa was in the 1/2 leaf stage, the area under cultivation was treated with compositions according to the invention.
Scoring of the damage to rice was carried out 2B days after the treatment, and damage to the remaining plants was carried out 56 days after the treatment. The results are compiled in Table 2.

20~286~

Table 2: ~erbicidal action tfield trial) % damage in Herbicide(s) Dosage rate Sl~Y CYSE SCIU MOVP Trans-[g of a.i./ha planted rice Al 10.5 40 30 1098 0 21.0 B8 60 75100 0 B1 10.5 45 65 7550 3 15.8 7~ 70 6565 5 21.0 70 75 7070 5 Al+B1 10.5+15.8 85 83 78100 3 10.5+21.0 93 85 9099 10 21.0+10.5 88 83 90100 3 21.0+15.8 90 85 93100 0 21.0+21.0 95 90 95100 3 Abbreviations:
a.i. = active ingredient (based on pure active substance) SAPY = Sagittaria pygmaea; transplanted tubers SCIU = Scirpus juncoides, seeded MOVP = Monochoria vaginalis, ~eeded CYSE = Cyperus serotinus; transplanted tubers A1 = 1-~(2-ethoxyphenoxy)sulfonyl]-3-(4,6-dLmethoxy-2-pyrimidinyl)-urea as 0.07% granules B1 = pyrazosulfuron-ethyl as 0.07% granules 5. Biological field trial Analogously to Example 4, wheat or ba:rley plots which were infested with weeds were treated in the Z- to 4-leaf stage and scored 4 to 6 weeks after the composition~
given in Table 3 had been applied; the results are compiled in ~able 3.

- 20 - 2~S28~
Table 3 % damage in ~erbicide(s) Dosage rate AMARE CHEAL POLSC TA ~V
[g of a.i./ha]
~
A1 11.25 8:3 39 45 0 0 22.5 8~ 41 76 0 0 8'~ 43 78 0 0 8g 92 86 0 Q

Al+B3 30+11.25 97 90 86 0 0 30+22.5 97 92 92 0 0 _ _ . . . . .
Abbreviations to Table 3:
a.i. = active ingredient (based on pure active substance) Al = 1-[(2-ethoxyphenoxy)sulfonyl]-3-(4,6-dimethoxy-2-pyrimidinyl)-urea and 0.3% wett.ing agent based on sodium salt of C~2/Cl4-fatty alcohol diglycol ether sulfate B3 = amidosulfuron with 0.3% wetting agent as in Al AMARE = Amaranthus retroflexus CHEAL= Chenopodium album POLSC = Polygonum scandens TA = Triticum aestivum (wheat~
HV = Hord~um vulgare (barley)

Claims

1. A herbicidal composition with an effective content of A) compounds of the formula (I) or salts thereof (I) in which a1) R1 is ethoxy, propoxy or isopropoxy and R2 is halogen, NO2, CF3, CN, C1-C4-alkyl, C1-C4-alkoxy,C1-C4-alkylthio or(C1-C4-alkoxy)-carbonyl and n is 0, 1, 2 or 3, or a2) R1 is optionally unsaturated C1-C8-alkoxy which is substituted by halogen, optionally unsatu-rated C1-C6-alkoxy, a radical of the formula (C1-C6-alkyl)-S-, (C1-C6-alkyl)-SO-, (C1-C6-alkyl)-SO2-, (C1-C6-alkyl)-O-CO-, NO2, CN or phenyl; furthermore C2-CB-alkenyloxy or -alkynyloxy and R2 is saturated or unsaturated C1-C8-alkyl, phenyl, phenoxy, C1-C4-alkoxy, C1-C4-alkylthio, (C1-C4-alkoxy)-carbonyl, it being possible for all the above R2 radicals to be substituted by halogen, C1-C4-alkoxy or C1-C4-alkylthio, or is halogen, NO2, C1-C4-alkylsulfonyl or -sulfinyl, and n is 0, 1, 2 or 3, or a3) R1 is C1-C8-alkoxy and R2 is C2-C8-alkenyl or -alkynyl, phenyl or phenoxy, the abovementioned R2 radicals being unsub-stituted or substituted by halogen, C1-C4-alkoxy or -alkylthio, or is C1-C4-alkylsulfonyl or -alkylsulfinyl and n is 1, 2 or 3, or a4) R1 - in each case in the 2-position on the phenyl radical - is halogen, methoxy, ethyl or propyl, R2 is (C1-C4-alkoxy)-carbonyl in the 6-position on the phenyl radical and n is 1, and, in all cases as)-a4), R3 is hydrogen, saturated or unsaturated C1-C8-alkyl or C1-C4-alkoxy, R4 and R5 independently of one another are hydrogen, halogen, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkyl-thio, the three last-mentioned radicals being unsubstituted or substituted by halogen, C1-C4 alkoxy or C1-C4-alkylthio, Y is O or S and E is CH or N, in combination with B) one or more compound(s) from the group com-prising the compounds B1) pyrazosulfuron-ethyl (NC 311) of the formula (B1) B2) bensulfuron-methyl of the formula (B2) B3) amidosulfuron of the formula (B3 ) B4) imazosulfuron (TH 913) of the formula (B4) B5) dimetrasulfuron (cinosulfuron) of the formula (B5) and B6) metsulfuron-methyl (DPX-T 6376) of the formula B6)

2. The composition as claimed in claim 1, which con-tains compounds of the formula (I) or salts thereof, in which a1) R1 is ethoxy, propoxy or isopropoxy and R2 is in the 6-position and has the abovementioned meaning, and n is 0 or 1, or a2) R1 is optionally unsaturated C1-C4-alkoxy which is substituted by halogen, C1-C4-alkoxy, C1-C4-alkylthio or -sulfinyl or -sulfonyl, (C1-C4-alkoxy)-carbonyl, NO2, CN or phenyl; furthermore C2-C5-alkenyloxy or C2-C4-alkynyloxy, and R2 is C1-C4-alkyl, C2-C5-alkenyl, (C1-C4 alkoxy)-carbonyl, C1-C4-alkoxy or C1-C4-alkylthio, each of which can be substituted as indicated above, or is halogen, and n is 0 or 1, or a3) R1 is methoxy, ethyl or propyl and R2 is 6-methoxycarbonyl or 6-ethoxycarbonyl and n is 1, and in all cases a1) - a3), R3 is hydrogen, C1-C4-alkyl, R4 and R5 are halogen, C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkylthio, the 3 last-mentioned radicals being unsubstituted or substituted by halogen, C1-C4-alkoxy or C1-C4-alkylthio, Y is O or S and E is CH or N.

3. The composition as claimed in claim 1 or 2, which contains one or more compounds of the formulae A1, A2 and A3 or salts thereof (A1) (A2) (A3)

4. The composition as claimed in one or more of claims 1 to 3, which contains 0.1 to 99% by weight of the active substances A and B, besides customary formulation auxiliaries.

5. The composition as claimed in one or more of claims 1 to 4, which contains the active substances A and B in a ratio by weight of 1:0.1 to 1:10.

6. A process for the preparation of a composition as claimed in one or more of claims 1 to 5, which comprises formulating one or more compounds A with one or more compounds B analogously to a conven-tional formulation for crop protection agents from the group comprising wettable powders, emulsifiable concentrates, aqueous solutions, emulsions, sprayable solutions (tank mix), dispersions on an oil or water base, suspoemulsions, dusts, seed-dressing agents, granules for soil application or for broadcasting, water-dispersible granules, ULV
formulations, microcapsules and waxes.

7. A method of controlling undesirable plants, which comprises applying to these plants or their areas of cultivation a herbicidally effective amount of a combination of active substances A + B as defined in one or more of claims 1 to 5.

8. The method as claimed in claim 7, wherein weeds in crops of useful plants are controlled selectively.

9. The method as claimed in claim 8, wherein the crop of useful plants is one from amongst the group com-prising wheat, barley, corn and rice.

10. The use of the herbicidal composition as claimed in one or more of claims 1 to 5 for selective weed control in crops of useful plants.