CA1158059A - Herbicidal compositions - Google Patents

Abstract

HERBICIDAL COMPOSITIONS
Abstract of the Disclosure Herbicidal compositions which comprise an amount of a com-pound A of the formula (A) in which R is chlorine or bromine, X is oxygen or sulfur, and R1 is hydrogen, (C1-C4)-alkyl or a cation equivalent, in combination with the compound ;

the weight ratio of the components (A) : (B) being prefer-ably from 5 : 1 to 1 : 20. The compositions are distinguished by a synergistic effect, especially against mono- and dicotyledonous weeds.

Description

1 1~8~59 It is known that herbicidal agents of the group of phenyl ureas, although being very efficient against dicotyledonous weeds, have insufficient activity in weed grasses or even none at all.
One of these compounds is known from Belgian Patent No. 864,029:

o H3C- ~ -CH2-CH2-O- ~ NH C N ~ 3 (hereinafter defined as compound B).
On the other hand, heterocyclically substituted 4-oxo-phenoxypxopionic acid derivatives (hereinafter de~ined as compound A) are proposed in German Offenlegungsschrift No. 2,6~0,730 as herbicides having a selective action against weed grasses of economic importance.
Surprisingly, it has now been found that a combined application of compounds A and B gives a synergistlc effect in combating undesirable mono- and dicotyledonous weeds.
Subject of the present invention are therefore com- -positions which comprise a compound A of the formula I
CH
R ~ -O- ~ ~-OC-COORl in which R is chlorine or bromine, X is oxygen or sulfur, and Rl is hydrogen, (Cl-C4)-alkyl or a cation equivalent, in combination with a synergistic amount of a compound B.
In the compounds of the formula I, R is preferably Cl or, likewise preferred, is in 6-position, that is para-position to N;
and Rl stands especially for (Cl-C4)-alkyl.
'~

-, . . ' ' '' ' :

-1 15~)59 The com~ounds A of the formula I have a center of asyM-metry at the alpha-C atom of the propionic acid radical, and they are present in racemic form when prepared from racemic starting materials. The two optical antipodes which can be 5 synthetized in known manner or ob-tained by racemate separa-tion can be mixed with B as readily as the racemates.
Especially suitable for such mixtures is the D (~) form of compound A.
The mixtures of the invention act against a wide range 10 of undesirable mono- and dicotyledonous weeds while simul-taneously sparing broad-leaf crop plants. They can therefore . be applied usefully, for example, for selectively combating broad-leaf weeds such as Amaranthus, Xanthium, Portulaca, Sida and Abutylon, as well as weed grasses such as wild 15 ~.illet (Setaria, Echinochloa, Panicum, Sorghum, Digitaria, Elensine), wild oats, annual blackgrass, quack-grass, Johnson grass and Bermuda grass in sugar beet, soybean, cotton and peanut cultures. In some cases, the compositions of the invention can be used selectively in rice cultures, 20 and they are suitable furthermore for applicatiGn in large plantations, viticulture, fruit growing and forestry.
The mixing ratio of the components may vary within wide limits of from about 5:1 to 1:20, and its choice de-pends on the prevailing weed spectrum, the development stage 25 of the weeds, and the second component of the mixture.
Preferred is a mixing ratio of from 3:1 to 1:6.
The herbicidal compositions of the invention can be formulated as wettable powders, emulsifiable concentrates, sprayable solutions, dusting agents or granules, and contai.n 30 the usual formulation additives such as wetting agents, ad-hesives, dispersing agents, solid or liquid inert sub-stances, and grinding auxiliaries or solvents. The herbicide content of the products so obtained is generally from 2 to 95 weight %. The herbicidal compositions of the invention 35 may be applied either as tank mixtures (active substances A

1 15~05~

and B fo~mulated separately and mixed before use) or as ready-to-use formulations.
Wettable powders are formulations which are uniformly dispersible in water and which, in adclition to the aetive compound and a diluent or iner-t substance, containing furthermore wetting agents, for example, polyoxyethylated alkylphenols, polyoxyethylated fatty alcohols, alkylsul-fonates or alkylphenylsulfonates, and dispersing agents, for example sodium ligninsul~onates, sodium-2,2'-dinaphthyl-methane-6,6'-disulfonate, sodium dibutylnaphthalene sul-fonate or the sodium salt of oleoylmethyl-taurine.
Emulsifiable concentrates are obtained by dissolving the aetive compound in an organic solvent, for example, butanol, cyclohexanone, dimethylformamide, xylene or even higher-boilins aromatics or hydrocarbons and adding one or more emulsifiers, for example: calcium salts of alkylarylsul-fonic acids such as Ca-dodec~rlben~enesulfor,at~; nonionic emulsifiers such as fatty acid polyglycol esters, alkyl arylpolyglycol ethers, fatty alcoh~l polyglyeol ethers;

2~ propyleneloxide~ethylene oxide condensation products, fatty aleohol/propylene oxide/ethylene oxide con~ensation pro-duets, alkyl polyethers, sorbitane fatty aeid esters, polyoxyethvlene/sorbitans fatty acid esters or polyoxy-ethylene sorbitol esters.
2~ Dusting agents are obtained by grinding the active e.ompound with finely divided solids, for example tale, natural elays, sueh as koalin, bentonite, pyrophillite or diatomaeeous earth.
Granules can be manufactured either by spraying the active eompound onto absorbent, granular inert material or by applying active compvund concentrates by means of adhesives, for example polyvinyl aleohol, sodium poly-aerylate or even mineral oils, onto the surfaces of carriers, such as sand, koalinites or granular inert material. Suitable formulations ean also be manufactured by the customary methods of manuEacture of fertilizer granules, if desired in admixture with fertilizers.
In the case of herbicidal agents, the concentrations of the active compounds in the commercial formulations can vary. In wettable powders, the active compound concentra-tion varies, for example, between about 10 and 80 %, the remainder consisting of one or more of the a~ovementioned formulation additives. In the case of emulsifiable concen-trates, the active compound concentration is about 10 %
to 80 %. Dust formulations usually contain 5 to 20 % of active compound, and sprayable solutions about 2 to 20 %.
In the case of granules, the active compound content in part depends on whether the active compound is in a li~uid or solid form and what granulating auxi]iaries, fillers and the like are used.
If necessary or desired the commercial concentrates may be diluted prior to application in the usual manner, for example by means of water in the case of wettable powders and emulsifiable concentrates. Dusts, granules and spray-able solutions are generally ready for use without further dilu-tion. The amount of active ingredient necessary for ob-taining the des-red result depends on e~ternal conditions such as temperature, humidity and the like. It can vary within wide limits, for example for type A from 0.005 to 5, preferably 0.01 to 3, kg of active substance per ha;
for type B from 0.2 to 8, preferably 0.4 to 5, kg/ha.
Especially, it is in the range of from 0.4 to 7 kg of the synergistic mixture of active substances per ha. The com-positions of the invention can be used in the pre-emergence process and especially advantageously in post-emergence;
and they are furthermore suitable as agent for adjusting the plant growth. They may be combined with other herbi-cides, insecticides and fungicides. Depending on the pre-vailing weed problem, other herbicidal agents may be added.
The following examples illustrate the invention.

-` l158~59 FORMUL~TION EXA~PLES
E X A M P L E A
An emulsifiable concentrate is obtained from 15 parts by weight of active substance A ~ type B
75 parts by weight of cyclohexanone as solvent and 10 parts by weight of oxethylated nonyl phenol t10 E03 as emulsifier.
E X A M P L E B
A wettable powder which is easily dispersible in water is obtained by mixing ~5 parts by weight of active substance *) 64 parts by weight of quartz containing kaolin as inert material 10 parts by weight of sodium lignosulfonate and 1 part by weight of sodium oleoyl-methyl-taurine as wett-ing and dispersing agent, and grinding the mixture in a pin mill.
E X A M P L E C
A dusting powder is obtained by mixirlg 10 parts by weight of active substance *) and 90 parts by weight of talc as inert material and comminuting the mixture in a hammer mill.
E X A M P L E D
A granular formulation consists, for example, of about 2 to 15 parts by weight of active substance *) and 98 to 85 parts by weight of inert granular materials such as attapulgite, pumice and quartz sand.

~) Active Substance: Herbicides A or B type; for ready-to-use formulations, the individual substances are separa~
tely formulated and subsequently ground with each other.
BIOLOGICAL EXAMPLES
The results of the greenhouse tests show in all cases an increased effect on application against weed grasses which can be defined as being synergistic. The synergistic effect was evaluated according to Colby S. R. "Calculating

3 0 5 9 Synergistic and Antagonistic Responses of Herbicide Com-binations" (Weeds 15 11967), 20 - 22). In some cases, it is increased to such an extent that with respect to the A type herbicides a considerably lower application con-centration than that which is hitherto known has the sameeffect, although component B alone has no significant activlty in weed grasses. The effect of component B against broad-leaf weeds is not substantially increased by the addition of A. Li~ewise, the corresponding crop plant is not damaged or adversely affected by the mixtures.
Example T
According to the post-emergence process, the herbici-des, alone or as mixtures, were applied in a greenhouse onto 18 days old plants. The tests were repeated 4 times.

4 Weeks after the treatment, the test was evaluated visually, and the damage of crop plants, weeds and weed grasses was determined in percent.
It was observed that the effect of the A herbicides in the mixtures against grasses is synergistically in-2n creased, the crop plants are not damaged, and the activityagainst the weeds it not adversely affected.
Example II
-According to the post-emergence process, the herbici-des and their mixtures were applied under greenhouse con-ditions onto 4 weeks old plants in pots. Also in this case, the tests were repeated 4 times. After a further 4 weeks,the herbicidal effect was evaluated visually. The results prove again the synergistic effect with respect to weed grasses and demonstrate that the individual components as well as the herbicide mixtures are substantially tolerated by the crop plants.
The survey of the test results is listed in the following Table. In each case, 12 ~ emulsifiable concen-trates of both active substances A1 and B were used which were applied in the form of correspondingly diluted -~ 1158V59 . ~

aqueous emulsions (about 400 l spray liquor/ha). The following greenhouse conditions were maintained:
Temperature: 21 - 24C in the daytime, 10 - 19C at night Relative atmaspheric moisture: 60 - 85 %
As crop plant, soybean was used, and the weeds or weed grasses were the following:
AMR = Amaranthus retroflexus (dikotyledonous, broad-leaf weed) ARA = Artemisia artsmisifolia (dikotyledonous, broad-lear weed) XCA = XanthiUm canadense (dikotyledonous, broad-leaf we~d) SAV = Setaria viridis (weed grass) DIS = Digitaria sanquinalis (weed grass) SRH = Sorghum halepense (weed grass) , , 1 1~8059 T a b l e Synergistic herbicidal effect and selectivity in post-emergence application Treatment Dose damage in ~ to ~eds or crop plant 4 weeks after with her- kg AS/ha herbicide a~plication bicide soybean _ ~ , XCA5~V DIS SRH
1.0 0 0 0 099 100 95 0.5 0 0 0 090 95 90 0.25 0 0 0 0~0 85 80 0.12 0 0 0 060 60 50 0.06 0 0 0 040 40 30 0.03 0 0 0 010 20 0 ______ __ _______. ~_________ ___ _. ___ ___ ____ _ . . _ .____. ._______ ___.__ B 2.0 5 100 98 9850 20 40 1.0 2 95 90 8030 0 20 0.5 1 0 70 ~0 60o 0 0 _ ______ 0 25 l 50 30 20 _______. .___ ___ ______ + B 0.03+0.25 i 0 40 30 30 50 40 ¦ 20 0.06+0.25 ~ 0 40 30 30 70 60 1 50 0.12+0.25 ' 0 60 50 30 90 ~0 ¦ 80 0.25+Q.25 ~ 0 50 50 30 100 98 ! 98 _______ __________ ~ ____ . __ .____ _ ___ ___ _ _____ _ _ ___. _ ___ _ ______ 0.03+0.5 1 0 60 ~70 70 70 60 60 0.06+0.5 1 0 70 60 70 90 80 75 0.12+0.5 1 0 70 70 75 98 92 90 0.25+0.5 070 70 80100 95 ~ 98 0.5 +0.5 075 75 801Q0 100 100 ____ ____ ,___________ _____ __ _ . _ __ __ __ _ __ _. _ __ _ 0.03+1.0 0 95 100 95 75 70 75 0.06+,.0 5 100 ~ 100 98 95 90 85 0.12+1.0 5 100 ~ 100 95 100 95 98 0.25+1.0 2 100 ~100 98 100 100 100 0.5 +1.0 . 5 100 98 98 100 100 100 _________ ___ ____ _ ____ ____ ___ _~__ ___ _, _ __. .____ -,~

-`` 115~059 A,~ = ~o ~ ~ O-cH-cooc2H5 }~ -~ CH2~H2-0~ ` ~CH3 : .

: : ~

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Claims (9)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A herbicidal composition which comprises a compound A of the formula (A) in which R is chlorine or bromine, X is oxygen or sulfur, and R1 is hydrogen, (C1-C43-alkyl or a cation equivalent, in combination with a synergistic amount of the compound of the formula .
(B)

2. A herbicidal composition as claimed in claim 1, wherein the ratio of active substances (A) : (B) is in the range of from 5:1 to 1:20.

3. A herbicidal composition as claimed in claim 1, wherein the ratio of active substances (A) : (B) is in the range of from 3:1 to 1:6.

4. A herbicidal composition containing from 2 to 95 weight %
of a combination of active substances as claimed in claim 1, 2 or 3, the remainder of the composition consisting essentially of usual formulation additives.

5. A herbicidal composition as claimed in claim 1, 2 or 3 wherein in compound (A) R is 6-chloro.

6. A herbicidal composition as claimed in claim 1, 2 or 3 wherein in compound (A) R1 is (C1-C4)-alkyl and R is 6-chloro.

7. A herbicidal composition as claimed in claim 1, 2 or 3 wherein in compound (A) R1 is (C1-C4)-alkyl, X is oxygen and R is 6-chloro.

8. A process for combating a mono- and dicotyledonous weeds or weed grasses, which comprises treating the correspondingly infested plant cultures, areas or substrates with a combination of compounds (A) and (B) as claimed in claim 1, 2 or 3, in a herbicidally effective amount.

9. A process for combating mono- and dicotyledonous weeds or weed grasses, which comprises treating the correspondingly infested plant cultures, areas or substrates with a combination of the compound of the formula and a synergistic amount of the compound of formula B as defined in claim 1.