CA1098726A

CA1098726A - Selective herbicidal agents

Info

Publication number: CA1098726A
Application number: CA267,089A
Authority: CA
Inventors: Hanskarl Kirfel; Helmut Hack
Original assignee: Bayer AG
Current assignee: Bayer AG
Priority date: 1975-12-04
Filing date: 1976-12-03
Publication date: 1981-04-07
Also published as: ATA893476A; GB1521007A; PT65912A; AT354799B; FI763472A; DK545776A; PT65912B; NL7613453A; AU2024376A; FR2333442A1; ES453906A1; DD128790A5

Abstract

Bayer 3033-PFF
SELECTIVE HERBICIDAL AGENTS
Abstract of the Disclosure Synergistic herbicidal combinations comprising:
(a) 3-(p-chlorophenyl)-2-chloropropionic acid methyl ester, of the formula (I), and at least one of (b) a surfactant component comprising at least one agriculturally acceptable surface-active agent (c) an oil component comprising at least one agricul-turally acceptable mineral oil alone or in admixture with a solid or liquid or liquefied gaseous diluent or carrier.
The surfactant is preferably chosen from (A) sorbitol fatty acid esters and polyoxyethylene sorbitol fatty acid esters (B) polyoxyethylene alkyl (or arylalkyl) ethers, and alkylpolyglycol ethers; and (C) silicone based surfactants and the compositions preferably contain all three components (a), (b) and (c).

Le A 16 814

Description

The present invention relates to new herbicidal combinations of 3-(_-chlorophenyl)-2-chloropropionic acid methyl ester and certain surface-active agents and/or certain oils.
It is known that 3-(_-chlorophenyl)-2-chloropropionic acid methyl ester possesses selective herbicidal properties (see U.S. Patent No.
3,472,646 and L. Eue in "Zeitschrift fur Pflanzenkrankheiten und Pflanzen-schutz", Special Issue IV (1968), pages 211-214). The compound is very suit-able for combatting Avena fatua, especially in cereals. However, it is a disadvantage that a relatively high amount of active compound must be used to achieve adequate activity.
Furthermore, it is known that the activity of herbicides which penetrate into the plants at least partially through the leaf can, in some cases, be improved by mixing the active compounds with surface-active sub-stances or oils (see Weeds 15, (1967) 87-89). Attempts which are aimed at increasing the herbicidal potency of the active compound 2-(N-benzoyl-3,4-dichlorophenylamino)-propionic acid ethyl ester, which is suitable for com-batting Avena fatua, by adding a surface-active substance, have, however, re-mained unsuccessful. This is evidenced by the publication of F. Bischof and H. Water, "Wirkung von SUFFIX (Benzoyl-propathyl) in Abhangigkeit von der Applikationsstelle bei Flughafer" (Action of SUFFIX (benzoyl-propethyl), as a function of the point of application, in the case of wild oats") in Zeit-schrift fur Pflanzenkrankheiten und Pflanzenschutz, Hohenheim, Special Issue VII (1975).
The present invention now provides a herbicidal composition con-taining from 10 to 90 percent of a mixture of active ingredients comprising (a) 3-(p-chlorophenyl)-2-chloropropionic acid methyl ester of the formula Cl ~ Cl (I) (b) a surfactant component consisting of a dodecyl polyglycol ether having an average of 7 ethylene oxide groups per molecule, and/or ~87Z6 (c) a paraffinic mineral oil having a density of about 0.87 g/cm3 at 15C, a viscosity of about 80 cSt at 20C, a pour point of about -15C
and a boiling range of about 350 to 450C, in which the mixture of active ingredients contains (i) the 3-(p-chlorophenyl)-2-chloropropionic acid methyl ester component (a) and the surfactant component (b) in a weight ratio of from 1:0.3 to 1:0.8, or (ii) the 3-(p-chlorophenyl)-2-chloropropionic acid methyl ester component (a) and the paraffinic mineral oil component (c) in a weight ratio of from 1:0.5 to 1:1.75, or (iii) the 3-(p-chlorophenyl)-2-chloropropionic acid methyl ester component (a) and a mixture of the surfactant component (b) and the paraffinic mineral oil component (c) in a weight ratio of 1:0.5 to 1:0.9 parts of (a) per part of mixture (b) and (c);
the balance of the composition being a suitable diluent or carrier.
The combinations according to the invention are substantially more suitable for the selective combatting of Avena fatua in cereals than the active compound 3-(p-chlorophenyl)-2-chloropropionic acid methyl ester used without additionalsurface-active compounds and/or oils. This must be described as extremely surprising, since it had to be assumed from the known state of the art, that it would be as impossible to increase the activity of 3-(_-chlorophenyl)-2-chloropropionic acid methyl ester by adding a surface-active compound or an oil as to increase that of the chemically similar wild-oat herbicide 2-(N-benzoyl-3,4-dichlorophenylamino)-propionic acid ethyl ester.
An important advantage of the combinations according to the invention is that they still ensure adequate combatting of Avena fatua in cereals even when they contain up to 30 percent by weight less of the active compound 3-(_-chlorophenyl)-2-chloropropionic acid methyl ester than those known agents which contain 3-(~-chlorophenyl)-2-chloropropionic acid methyl ester without addi-tional surface-active compounds and/or oils. Accordingly, the combinations 9t3~26 according to the invention represent a valuable enrichment in the herbicide art, particularly in controlling wild oats (avena fatua~.
3-(p-chlorophenyl)-2-chloropropionic acid methyl ester of the formula (I), contained in the combinations according to the invention, and its use as a selectively acting herbicide, are already known from U.S. Patent No. 3,472,646.
The surface-active agent (b) which can be present in the com-binations according to the invention, namely, a dodecyl polyglycol ether with an average of 7 ethylene oxide groups per molecule, is commercially available under the trade na~e of "OX". These surface-active agents are known; they do not exhibit any herbicidal properties when applied in quantities in which they are commonly used as surfactants.
As paraffinic mineral oils which can be present in the combina-tions according to the invention, the following oil is preferentially em-ployed, namely, a paraffinic mineral oil which has a density of 0.868 g/cm3 at 15C, viscosities of 77.5 cSt at 20C, 19.9 cSt at 50C and 151 SUS at 100F, a pour point of -15C and a boiling range, according to DIN (German Industrial Norm) 51,356, wherein boiling starts at 372C and ends at 456C.
These paraffinic mineral oils are known; they are products which are sold by the British Petroleum Company under the trade mark "ACTIPRON". These paraffinic mineral oils do not exhibit any herbicidal properties when applied in quantities in which they are commonly used in plant protecting agents.
As already mentioned, the combinations according to the invention cont~in in addition to the active ingredient of the formula (I) the surface-active agent (b) and/or the paraffinic mineral oil (c). Particularly suitable for the selective control of Avena fatua are those combinations which in addi-tion to the compound of the formula (I) contain the surface-active agent (b) as well as the paraffinic mineral oil (c).
The good selective herbicidal activity of the combinations ac-cording to the invention manifests itself particularly strongly at certainconcentration ratios. However, the weight ratios of the active compound of the formula (I) to the additives (b) and/or (c) can vary within a certain ~(~98726 range. In general, 0.3 to 0.8 parts by weight, preferably 0.4 to 0.6 parts by weight, of surface-active agent (b) are present per part by weight of active compound of the formula (I). Furthermore, in general 0.5 to 1.75 parts by weight, preferably 0.75 to 1.50 parts by weight of paraffinic oil (c) arepresent per part by weight of active compound of the formula (I). If combinations are used which in addition to the active compound of the formula (I) contain the surface-active agent (b) as well as the paraffinic mineral oil (c), then, in general, 0.5 to 0.9 parts by weight, preferably 0.6 to 0.8 parts by -~ - 5 -:',.~

~g~7Z6 ~e h~ Cb) weight, of surface-active ~ents (II) and paraffinic oi~ (c) mineral oilE (III)-are present per part by weight of active compound of the formula (I).

The combinations according to the invention exhibit a very good selective herbicidal activity against Avena fatua in cereals, such as, for example, barley and wheat.
The combinations according to the invention can be con-ve~ted into the usual formulations, such as solutions, emulsions, suspensions, powders and pastes. These are produced in known manner, for example by mixing the active compounds with extenders, that is, liquid or solid or liquefied gaseous diluen~s or carriers, optionally with the use of surface-active agents, that is, emulsi-fying agents and/or dispersing agents and/or foam-forming agents. In the case of the use of water as an extender, organic sol~ents can, for example, also be used as auxiliary solvents As liquid diluents or carriers, there are preferably ~sed aromatic hydrocarbons, such as xylenes,toluene, benzene or ~lkyl naphthalenes, chlorinated aromatic or aliphatic hydro-carbons, such as chlorobenzenes, chloroethylenes or methylene chloride, aliphatic hydrocarbons, such as cyclohe~ane or paraf~ins, for example mineral oil fractions, alcohols, such as butanol or glycol as well as their ethers and esters, ketones, such as acetone, methyl ethyl ketone, methyl iso-butyl ketone or cyclohexanone, or strongly polar solvents, such as dimethyl ~ormamide, dimethyl sulfoxide or aceto-nitrile, as well as water.

Le A 16 814 ~ ~ ~

~y liquefied ~aseous diluents or carriers are meant liquids which would be ~aseous at normal temperatures and pressures, for example aerosol propellants, such a~ halo-gCl~t('d hydrocarbons, for cx~mple freon.
As solid diluents or carriers, there are preferably used ~round natural minerals, such as kaolin~, clays, talc, chalk, quartz, attapulgite, montmorillonite or diatomaceous earth, or ~round ~ynthetic miner~l~, such as hiehly-disper~ed silicic acid, ~lumin~ or silicates.
1o Preferred examples of emulsifying and foam-forming agent8 inclu~e non-ionic and anionic emulsiiiers, such as polyo2y-ethylene-fatty acid esters, polyoxyethylene-fatty alcohol ethers, for e~a~ple alkylarylpolyglycol ether~, ~lkyl sulphonates, alkyl sulfate3 and aryl sulfonates as well as albumin hydrolyzation products; and preferIed e2amples of dispersing agents include lign~n sulphite waste liquors and methyl cellulose.
The combinations according to the invention can be present in the formulations as a m ~ture with other active compounds.
The formulations in general contain from 10 to 90 per cent by weight, preferably from 15 to 80 per cent by weight, o active com~ound co~bination according to the invention.
The combinations according to the invention can be used as such, in the form of their formulations or as the use forms prepared therefrom, such as ready-to-use solutions, e~.ulsion3, foams, and suspensions. They may be used in the customary manner, for example by atomizing, spraying and watering and scattering.

The amounts used of the active compound combinations according to the invention can be varied within a fairly r Le A 16 814 _ ~ _ 72~

wide ranBe. In general, they lie between 0.5 and 20 kg/ha, preferably between 2 and 15 k~/ha.
The combinations according to the invention are, in eeneral, used after the emergence of the plants.
The present invention therefore also provide~ a method of combatin~ weed~ which comprises applying to the weeds, or to a habitat thereof, a composition of the present invention.
The present invention further provideq crops protected from d~qge by weeds by being grown in areas in which i~ediately prior to and/or during the time of the growing a composition of the present invention was applied.
It will be seen that the usual methods of providing a harvested crop may be improved by the present invention.
The good ~elective herbicidal action of the combina-tions according to the invention aeainst Avena fatua in cereals can be seen from the examples which follow.

Exam~le 1 _ost-emer~ence te~t in the o~en ~olvent: Diisononyl phthalate ~ulsifier: A mi~ture of (a) an alkylaryl polyglycol ether with an average of 17 ethylene o~ide grou?s per molecule, (b) an alkylaryl polyglycol ether with an average o~ 27 ethylene oside groups per ~olecule and (c) a 901ution of calcium dodecyl-benzenesulphonate in butanol.
To prepare a suitable formulation of active conpound, 67.2 per cent by weight of 3-(P-chlorophenyl)-2-chloro-propionic acid methyl ester were first mi~ed with 10 parts by weight o~ the above-mentio~ed emulsifier and 22.8 parts by weight o~ the above-mentioned solvent. Thereafter, s Le A 16 814 _ ~ _ ready-to-use spray liquors were prepared by (a) emulsi~ying 1 part by weight oi the said sctive-compound formulation in the desired amount of water, (b) emulqifying 1 part by weight oi the said active-compound ~ormulation and 0.40 part by weight of surface-. ~on. pou nJ ~b) active e-ompound (II 10) in the desired amount of water and (c) emulsifying 1 part by weight of the said active-com-pound formulation and 0.99 parts by weight o~ paraffinic mineral oil (III-1) desired amount of water.
In the open, plots with test plantq which were 6 - 15 cm high were wetted uniformly with the particular spray liquor, in such a way that the a~ounts oi active compound per unit area indicated in the following table were applied.
The concentrations of the spray liquors were so chosen that the amounts o~ active compound indicated in the table were applied in 300 l oi water per hectare. The dosage o~ the active compound or oi the active compound combinations and of the amounts of water used was decisive in the present case, since the spray liquor should not drip onto the soil, as the active compound can only enter the plant through the leaf. Before harvesting, the degree oi action was assessed by visually determining the number oi Avena iatua panicles on the treated plots and comparing it with the number oi Avena iatua panicles on the untreated control plots. The values were e~pressed in %. The degree oi da~age oi the crop plants was also assessed as % damage in comparison to the development o~ the untreated control.
The figures denote:
0~0 = no action (like untreated control) 100~0 = total destruction.
The active compounds, the amounts used a~d the results can be seen irom the tableqwhich iollows:
Le ~ 16 814 - ~ -o h O O O O O O O O O O

a v~ rO O O O O O O O O O O

a ~ 1` CJ~ O 00 0 o o o o ~ ~

roooC~Iet 0 ~ ~ ~ ~O r~

,, In O O
o ~ 00 ~ O no U~ o o + + +
~ ~ ~ Ln ~ ~ ~

~ a ~ o ~ 5 [~3 [~

Example 2 Post-emergence test in the open A) Known preparation Solvent: Diisononyl phthalate Emulsifier: A mixture of (i) an alkylaryl polyglycol ether with an average of 17 ethylene oxide groups per molecule, ~ii) an alkylaryl polyglycol ether with an average of

2 7 ethylene oxide groups per molecule and (iii) a solution of calcium dodeeyl-benzenesulphonate in butanol.
To prepare a suitable formulation of active compound, 67.2 parts by weight of 3-(~-chlorophenyl)-2-chloro-propionic acid methyl ester were mixed with 10 parts by weight of the above-mentioned emul-sifier and 22.8 parts by weight of the above-mentioned solvent and the concentrate was diluted with water to the desired concentration.

B) Preparation according to the invention Solvent: Xylene Emulsifier: Solution of calcium dodecyl-ben~enesulphonate in butanol To prepare a suitable formulation of active compound, 41.3 parts by weight of 3-(~-chlorophenyl)-2-chloro-propionic acid methyl ester were mixed with 6.3 parts by weight of the above-mentioned emulsifier, 9.3 parts by weight of the surface-active agent (b), 25.7 parts by weight of the paraffinic mineral oil (c), and 17.5 parts by weight of the above-mentioned solvent and the concentrate was diluted with water to the desired concentration.

,, - 1 1 -'726 In the open, plots with test plants which were 6-15 cm high were wetted uniformly with the spraying liquids A or B, in such a way that the amounts of active co~pound per unit area indicated in the following table were applied.
The concentrations of the spray liquors were so chosen that the amounts of active compound indicated in the table were applied in 300 1 of water per hectare. The dosage of the active compound or of the active compound combinations and of the amounts of water used was decisive in the present case, since the spray liquor should not drip onto the soil, as the active compound can - only enter the plant through the leaf. Before harvesting, thedegree of action was assessed by visually determining the degree of coverage with Avena fatua panicles on the treated plots and comparing it with the degree of coverage with Avena fatua panicles on the untreated control plots. The values were expressed in %. The degree of damage of the crop plants was also assessed as % damage in comparison to the development of the untreated control.
The figures denote:
0~/0 = no action (like untreated control) 100% = total destruction.

The active compounds, the amounts used and the results can be seen from the table which follows:

Le A 16 814 ~~

l~g~7~

~ c ~ s~
~ ~ ~ o o o o o o ~ q ~
a v, 3 O ~ , ~rl h ~ O O O O O O
o\
a V~,D

~ ~1 s ,~ ~ 00 ~ ~ 00 ~

et 00 ~ ~ ~ A e~

t~ 0 00 ~0 + + + +
o 3~

~ C7 ,, , ~r ~ ~--~ O ~
~ ~ ~ , `~ ~

~ ~ ~ -- ~ A A -- ~

72~

It will be understood that the specification and examples are illustrative but not limitative of the present invention and that other embodiments within the spirit and scope of the invention will suggest themselves to those skilled in the art.

P 1~ .
Le A 16 814 - ~ -

Claims

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

1. A herbicidal composition containing from 10 to 90 percent of a mixture of active ingredients comprising (a) 3-(p-chlorophenyl)-2-chloropropionic acid methyl ester of the formula (I) (b) a surfactant component consisting of a dodecyl polyglycol ether having an average of 7 ethylene oxide groups per molecule, and/or (c) a paraffinic mineral oil having a density of about 0.87 g/cm3 at 15°C, a viscosity of about 80 cSt at 20°C, a pour point of about -15°C
and a boiling range of about 350 to 450°C, in which the mixture of active ingredients contains (i) the 3-(p-chlorophenyl)-2-chloropropionic acid methyl ester component (a) and the surfactant component (b) in a weight ratio of from 1:0.3 to 1:0.8, or (ii) the 3-(p-chlorophenyl)-2-chloropropionic acid methyl ester component (a) and the paraffinic mineral oil component (c) in a weight ratio of from 1:0.5 to 1:1.75, or (iii) the 3-(p-chlorophenyl)-2-chloropropionic acid methyl ester component (a) and a mixture of the surfactant component (b) and the paraffinic mineral oil component (c) in a weight ratio of 1:0.5 to 1:0.9 parts of (a) per part of mixture (b) and (c);
the balance of the composition being a suitable diluent or carrier.

2. A herbicidal composition as claimed in claim 1 comprising both said surfactant component (b) and said oil component (c) in addition to com-ponent (a).

3. A herbicidal composition as claimed in claim 1 consisting essen-tially of components (a) and (b) wherein said ratio of component (a) to com-ponent (b) is from 1:0.4 to 1:0.6.

4. A herbicidal composition as claimed in claim 1 consisting essen-tially of components (a) and (c) wherein said ratio of component (a) to com-ponent (c) is from 1:0.75 to 1:1.50.

5. A herbicidal composition as claimed in claim 1 consisting essen-tially of components (a), (b) and (c) wherein said ratio of component (a) to the mixture of components (b) and (c) is from 1:0.6 to 1:0.8.

6. A herbicidal composition as claimed in claim 1 containing from 10 to 90 percent of total active ingredients (a) plus (b) and/or (c) by weight.

7. A herbicidal composition as claimed in claim 6 containing from 15 to 80 percent of total active ingredients by weight, the balance being con-stituted by an inert agriculturally acceptable carrier.

8. A method of combatting weeds which comprises applying to the weeds, or to a habitat thereof, a herbicidal amount of a composition according to claim 1.

9. A method as claimed in claim 8 in which the active compounds are applied to an area of agriculture in a total amount of 0.5 to 20 kg per hectare.

10. A method as claimed in claim 8 in which the active compounds are applied to an area of agriculture in a total amount of 2 to 15 kg per hextare.

11. A method as claimed in claim 8, 9 or 10 in which the weeds are Avena fatua.

12. A method as claimed in claim 8, 9 or 10 wherein the composition is applied to an area of cereal cultivation.

13. A method as claimed in claim 8, 9 or 10 in which the weeds are Avena fatua and the composition is applied to an area of cereal cultivation.

14. A method of combatting weeds which comprises applying to the weeds, or to a habitat thereof, a herbicidal amount of a composition according to claim 2, 3 or 4.

15. A method of combatting weeds which comprises applying to the weeds, or to a habitat thereof, a herbicidal amount of a composition according to claim 5, 6 or 7.