SYNERGISTIC INTERACTION OF HERBICIDAL ARYLOXYPROPIONIC ACID DERIVATIVES AND CYCLOHEXANEDIONES

Abstract: A synergistic herbicidal composition comprising: (a) an aryloxypropionic acid derivative of formula (I) and (b) a cyclohexanedione derivative of formula (II).

Description: SYNERGISTIC INTERACTION OF HERBICIDAL ARYLOXYPROPIONIC ACID DERIVATIVES AND CYCLOHEXANEDIONES Background of the Invention The protection of crops from weeds and other vegeta tion which inhibit crop growth is a constantly recurring problem in agriculture. To help combat this problem, re¬ searchers in the field of synthetic chemistry have produced a extensive variety of chemicals and chemical formulations effective in the control of such unwanted growth. Chemical herbicides of many types have been disclosed in the literature and a large number are in commercial use. In some cases, active herbicides have been shown to be more effective in combination than when applied individu¬ ally. The result is often termed "synergism 11 , since the combination demonstrates a potency or activity level exceeding that which it would be expected to have, based on a knowledge of the individual potencies of the components. The present invention resides in the discovery that certain aryloxypro- pionic acid derivatives and certain cyclohexanediones, already known individually for their herbicidal potency, display a synergistic effect when applied in combination. Prior Art The two classes of compounds forming the combination which is the subject of the present invention are independentl known in the art for their effects on plant growth. Herbicida aryloxypropionic acid derivatives are disclosed in U.S. Patents Nos. 4,267,336, 4,317,913 and 4,414,391; British Patents Nos. 1,599,121 and 2,002,368. Also, see the Pesticide Manual. 9th ed. r edited by C. R. Worthing and R. J. Hance, pp. 400, 401 and 463. Derivatives of cyclohexanediones are disclosed as herbicides in U.S. Patent 3,950,420, EPA 80301, EP-B-85529. Description of the Invention It has now been discovered that εynergism in the control of undesirable vegetation is exhibited by compositions comprising: (a) An aryloxypropionic acid derivative of the formula in which X is hydrogen or halogen; is hydrogen, C -C 8 alkyl, C.-C 6 alkoxyalkyl; and (b) a cyclohexanedione derivative of the formula in which R is independently hydrogen; halogen; nitro; cyano; C 1.-Co, alkyl; CI-CD, alkyl substituted with a substituent selected from the group consisting of halogen, nitro, hydroxy, C.-Cg alkoxy and C.-Cg alkylthio; C 2 -C 8 alkenyl; C 2 -C 8 alkynyl; hydroxy; C.-C 8 alkoxy; C.-C 8 alkoxy substituted with a sub¬ stituent selected from halogen and C -C alkoxy; C_-C alkenyl oxy; C--C- alkynyloxy; C 2 ~C 6 alkanoyloxy; (C 1 ~C 6 alkoxy)- carbonyl; C.-C alkylthio; C.-Cg alkylsulfinyl; ^-Cg alkyl- sulfonyl; sulfamoyl; N-C( -C 8 alkyl)sulfamoyl; N,N-di(C.-C 8 alkyl)sulfamoyl; benzyloxy, substituted benzyloxy wherein the benzene ring is substituted with from one to three substi- tuents selected from the group consisting of halogen, nitro, C.-C, alkyl, C -C. alkoxy and C.-C, haloalkyl; the group NR 9R10 wherein R9 and RIO are independently selected from the group consisting of hydrogen, C.-C 8 alkyl, C 2 -C 8 alkanoyl, benzoyl and benzyl; the groups formyl and C 2 -C 8 alkanoxyl and the oxi e, imine and Schiff base derivatives thereof; and at least one of X is not selected from the group consisting of halogen, C -C 8 alkyl and C.-C 8 alkoxy; R 2 is C -C 8 alkyl, C 2 ~C g alkenyl, C 2 -C 8 haloalkenyl, C_-C 8 alkynyl, C_-C 8 haloalkynyl, a substituted -C_ alkyl, substituted with halogen, C.-C 8 alkoxy, C.-C 8 alkylthio, phenyl, substituted phenyl wherein the phenyl is substituted with halogen, nitro, cyano, C.-C 8 alkyl, C -C 8 haloalkyl, C.-C 8 alkoxy and C.-C 8 alkylthio; R- is hydrogen, C.-C 8 alkyl, C.-C 8 fluoroalkyl, C 2 ~C g alkenyl, C 2 -C 8 alkynyl and phenyl; R. is hydrogen or the keto tautomer; C.-C 8 alkyl; C -C 8 alkenyl; C 2 -C 8 alkynyl; substituted C.-C 8 alkyl wherein the alkyl group is substituted with C.-C 8 alkoxy, C.-C 8 alkylthio, C.-C 8 alkoxycarbonyl, phenyl, and substituted phenyl wherein the benzene ring is substituted with 1 to 3 substituents selected from the group consisting of halogen, nitro, cyano, C.-C 8 alkyl, C.-Cg haloalkyl, C.-Cg alkoxy, and C.-C 8 alkylthio; C.-Cg(alkyl) sulfonyl; benzene sulfonyl; substituted benzene sulfonyl wherein the benzene ring is substituted with 1 to 3 substituents selected from the group consisting of halogen, nitro, cyano, C.-C alkyl, C.-C 8 haloalkyl, C^Cg alkoxy and C^Cg alkylthio; an acyl group an an inorganic or organic cation; and n is an integer chosen fro 2 to 5. The terms "alkyl", "alkoxy", "alkenyl", "alkylthio", and the like are used herein to embrace both straight-chain and branched-chain radicals. Examples of aryloxypropionic acid derivatives useful in the present invention are: (D)-butyl 2-[4-(5-trifluoromethyl-2-pyridyloxy)- phenoxy]-propionate, (fluazifop-butyl) ; ( luazifop) ; (R) -2- [4- (5-trif luoromethyl-2-pyridyloxy) phenoxy ] propionic acid, (fluazifop-P and fluazif op-P-butyl) ; (RS) -2- [4-(3-chloro-5-trif luoromethyl-2-pyridyloxy) phenoxy] propionic acid, (haloxyfop) ; haloxyf op-etotyl ; haloxyf op-methyl . These and other aryloxypropionic acid derivatives within the scope of the invention can be prepared by the procedures described in U. S. Patents Nos. 4, 267 , 336, 4 , 317 , 913 , 4,414, 391; EPA 23785; and British Patents Nos. 1, 599, 121 and 2, 002 , 368. These references are hereby incorporated in their entirety. Preferred cyclohexanediones included in the present invention are those in which the phenyl group is substituted with methyl groups and include: 5 - ( 3 -acetyl-2 , 4 , 6-tr imethy lpheny 1 ) -2 - [ 1- ( ethoxy- i ino ) -propy 1 ] -3 -hydr oxycyclohex-2 -en-l-one ; and 2- [1- (ethoxyimino) propyl ] -3-hydroxy-5- (2 ,4, 6-tri- methyl-3-butyrylphenyl) cyclohex-2-enone . The most preferred substituents are on the 2- and 6-position of the phenyl ring and are preferably selected from halogen, methyl and methoxy. These and other cyclohexanediones along with their tautomeric forms within the scope of the present invention, can be prepared by the procedures described in U.S. Patent 3,950,420, EP-A-0080301 and EP-B-0085529. These references are hereby incorporated in their entirety. The terms "synergism" and "synergistic" are used herein to convey the result observed when a combination of herbicides demonstrates a potency in excess of that which the combination would be expected to produce on the basis of the potencies of each herbicide applied individually. The term "herbicide" is used herein to denote a compound which controls or modifies the growth of plants. The term "herbicidally effective amount" is used to indicate the quantity of such a compound or combination of such compounds which is capable of producing a controlling or modifying effect. Controlling or modifying effects include all devia¬ tions from natural development, for example: kill, retar¬ dation, leaf burn, dwarfing and the like. The term "plant" refers to all physical parts of a plant, including seeds, seedlings, saplings, roots, tubers, stems, stalks, foliage and fruits. In the compositions of this invention, the aryloxy- propionic acid derivative:cyclohexanedione weight ratio at which the herbicidal response is synergistic, lies within the range of 1:5 to about 30:1, preferably about 1:5 to about 15:1 and most preferably about 1:2 to about 8:1. Application rates will depend upon the particular compounds chosen for use, the particular plant species and degree of control desired. In general, the compositions of the invention are most efficiently employed at a rate of 0.001 to 50 pounds per acre (0.001 to 56 kilograms per hectare), preferably 0,001 to 25 pounds per acre (0.001 to 28 kilogram per hectare) . The following examples provide further illustratio demonstrating the synergistic herbicidal response of the present compositions. Example I This example demonstrates the synergistic response of butyl (R)-2-[4-(5-trifluoromethyl-2-pyridyloxy)phenoxy] propionic acid (fluazifop-P-butyl) and 2-[l-(ethoxyimino)- propyl]-5-(2,4,6-trimeth l-3-butyryl phenyl)-1,3-cyclohexane- dione in combined postemergence application to the plants giant foxtail and shattercane. Plastic pots were filled with 2 parts sandy loam an 1 part peat moss mixed together containing the commercial fungicide cis-N[(trichloromethyl)thio]-4-cyclohexene-l,.2- dicarboximide (Captan ® ) and 17-17-17 fertilizer (percentages of N-P 2 0 5 - 2 0 on a weight basis) . Each pot was seeded to a single plant species. The plant species included giant foxtail (Setaria faberi) and shattercane (Sorghum vulgare) . The pots were placed in a greenhouse for approximately two weeks where they were watered regularly. The greenhouse temperature was approximately 85° F. day and 80° F. night. At the end of this period, the foliage on the emerged plants was sprayed with herbicidal emulsions formed by diluting emulsifiable concentrates of test compounds with adjuvants and water. The dilutions were made such that at a total spray volume of 25 gallons per acre, the amount of each test compound applied per pot corresponded to the desired application rate in ounces per acre. In control pots, the test compounds were applied individually at various applica¬ tion rates, whereas in the test pots, emulsions contained both compounds. Untreated pots were used as standards. Sixteen days after treatment, the control and test pots were compared to the standards and rated visually in terms of percent control ranging from 0% to 100%, with 0% representing no injury to the plant species and 100% repre¬ senting complete kill of all plants. All types of plant injury were taken into consideration. For the plant species, the results of these tests are listed in Table I in the columns headed by the symbol "0" (indicating the "observed" results) , each figure represent th average of three replications of the same test. These result are compared with the expected results, shown in the columns headed by the symbol "E", derived from the control data using Limpel's formula (Limpel et al., 1962, "Weed Control by Dimethylchloroterephthalate Alone and in Certain Combinations" Proc. NEWCC. , vol. 16, pp. 48-53): E = X + Y - XY 100 where X = observed percent injury when one of the herbicides is used alone, and Y = observed percent injury when the other herbicide is used alone. An asterisk (*) is used to indicate the tests where the results show synergism, i.e., where the observed result exceeds the expected result by at least 10 percent. It is clear from the table that synergism was observed at many of the application rates tested. a TABLE I 0 TABLE I (continued) Application Rates % Control - O:Observed, E:Expected (Oz /A) G ant Foxtail Shattercane A B 0.500 0.016 0.500 0. 03 0.500 0. 063 0.500 0. 125 0.500 0. 250 1. 000 0. 016 1. 000 0. 031 1. 000 0. 063 1. 000 0. 125 1. 000 0.250 1 2 Treatments contained 1% Agridex 16 days after application * _= denotes synergistic effect shown A = Fluazifop-P-butyl; butyl (R)-2-[4-(5-trifluoromethyl-2- pyridyloxy)phenoxy]propionic acid B = 2-[1-(ethoxyimino)-propyl]-5-(2,4,6-trimethyl-3-butyryl- phenyl)-1,3-cyclohexanedione Example II In this example, the following formulations were prepared from 2-[l-ethoxyimino)propyl]-3-hydroxy-5-(2,4,6- trimethyl-3-butyrylphenyl)cyclohex-2-enone (Herbicide A) , and the D isomer of butyl 2-[4-(5-trifluoromethyl-2-pyridyloxy)- phenoxy]-propionate (Herbicide B) . Formulation (a) : Herbicide (A) , 125 g/1; nonionic emulsifier (methyl capped derivative of Renex 650) , 20 g/1; Aerosol OT 100, 30 g/1; and Teneco 500/100 to 1 liter. Formulation (b) : Herbicide (B) , 125 g/1; phehyl sulfonate CALX, 45 g/1; Geopon SF 365, 45 g/1; Synperionic NPE 1800, 10 g/1 and Solvesso 100 to 1.0 liter. Field plots 2m x 2m were seeded with oilseed rape (Brassica campestrisϊ and the plant species, perennial ryegras (Loliu perenne) and annual bluegrass (Poa annua) . At the time of spraying, the oilseed rape was at the 2-true leaf growth stage, the annual bluegrass was at the 3-leaf, 2-tille stage of growth, and the ryegrass was at the 2-leaf growth stage. Formulations (a) and (b) above were each blended separately with 0.1% by weight of Agral and the resulting solutions were applied sequentially at various rates. Injury ratings were taken by visual determination 87 days after treatment. A scale of 0 to 10 is used where 10 is equivalent to complete kill (or 100 percent control) and 0 indicates no visual injury (or 0 percent control) as compared to untreated control plants. For the plant species, the results of these tests are listed in Table II in the columns headed by the symbol "0 (indicating the "observed" results) . These results are compared with the expected results, shown in the columns headed by the symbol "E", as determined by the Colby formula. The Colby formula is utilized to demonstrate the presence or absence of synergism (Colby, R. S., "Calculating Synergistic and Antagonistic Responses of Herbicide Combina¬ tions", 1967 Weeds, vol. 15, pp. 20-22): Expected effect = X + ( 10 ° " χ )Y 100 where X = observed effect of A and Y = observed effect of B The basis of demonstration by comparison with the Colby formula is that Herbicide (A) tested alone will kill a proportion of the target weeds and leave a proportion (a%) as survivors. Similarly, Herbicide (B) tested alone will leave (b%) as survivors. When combined, A + B will, however, if synergy is absent, act independently on the target weed, component A again leaving a% survivors, which survivors will be controlled by component B, with an overall effect of a% x b% 100 If, in practice, the percent control (degree of kill) is greater than that predicted by the Colby formula, synergism is provided by the difference between the observed and expected (Colby determined) results. As can be seen from Table II, synergism is widely evident. A = 2-[1-(ethoxyimino)propyl]-3-hydroxy-5-(2,4,6-trimethyl- 3-butyrylpheny1)cyclohex-2-enone. B = D isomer of butyl-2-[4-(5-trifluoromethyl-2-pyridyloxy) phenoxy]propionate where O = no injury 10 = complete kill Example III This example demonstrates the synergistic response of Herbicide (B) used in Example I and 5-(3-acetyl-2,4,6- trimethylphenyl)-2-[1-(ethoxyimino)-propyl]-3-hydroxycyclohe 2-en-l-one (Herbicide C) . The following formulations were prepared: Formula tion (b) included Herbicide (B) , 125 g/1; emulεifier 50 g/1; made up to 1.0 liter with Solvesso 100; and formulation (c) included Herbicide (C) , 125 g/1; non-ionic e ulsifier, 110 g/1; anisole, 400 g/1 made up to 1.0 liter with Solvesso 150. Pots in the greenhouse were seeded with large crabgrass (Digitaria sanguinalis) , barnyardgrass (Echinochloa crusgalli) , goosegrass (Eleusine indica), guineagrass (Panicu maximum) , and johnsongrass (Sorghum halepense) . At the time of spraying, each plant species had 4 - 5 leaves per plant. The above formulations were blended and the final solution blended with 0.1% by weight of AGRAL 90 an 1.0% by weight of ACTIPON. The final solution was applied through a greenhouse track sprayer at a volume of 200 liters per hectare. Nineteen days after treatment, the degree of injury was rated visually in terms of percent control ranging from 0 to 100%, with 0% representing no control and 100% representin complete kill of all plants in the pot. The degree of kill was then assessed and compared with the expected kill as determined by the Colby formula presented in Example II. It is clear from Table III that synergism was observed at many o the application rates tested. pyridyloxy)phenoxy]-propionate C = 5-(3-acetyl-2,4,6-trimethylphenyl)-2-[l-ethoxyimino)- 2 propyl]-3-hydroxycyclohex-2-en-l-one = 19 days after treatment * = Synergistic effect shown, the observed result exceeded the expected result by at least 10 percent The compositions of this invention are useful c._5 herbicides demonstrating synergistic activity for the control of undesirable vegetation. The compositions can be formulated in the same manner in which herbicides are generally formu¬ lated. The compounds may be applied either separately or combined as part of a two-part herbicidal system. The object of the formulation is to apply the compositions to the locus where control is desired by a convenient method. The "locus" is intended to include soil, seeds, and seedlings, as well as established vegetation. Formulations will generally contain several addi¬ tives. Among these are some inert ingredients and diluent carriers such as organic solvents, water, oil and water, water in oil emulsions, carriers of dust and granules, and surface active, wetting, dispersing, and emulsifying agents. Fertilizers, such as ammonium nitrate, urea, potash and superphosphates may also be added. .Aids to rooting and growth, such as compost, manure, humus, sand, etc. may likewise be added. The formulations are commonly dusts, wettable powders, granules, solutions or emulsifiable concentrates. Dusts are free-flowing powder compositions contain¬ ing the herbicidal compound impregnated on a particulate carrier. The particle size of the carrier is usually in the approximate range of 30 to 50 microns. Examples of suitable carriers are talc, bentonite, diatomaceous earth, and pyrophyl lite. Anticaking and antistatic agents can be added, if desired. The composition generally contains up to 50% of active ingredient. Dusts, like liquid compositions, can be applied by spraying from boom sprayers, hand sprayers or airplanes. Wettable powders are finely divided compositions comprising a particulate carrier impregnated with the herbi¬ cidal compound and additionally containing one or more surface active agents. The surface active agent promotes rapid dispersion of the powder in aqueous medium to form stable, sprayable suspensions. A wide variety of surface active agents can be used, for example, long chain fatty alcohols; salts of sulfonic acid; esters of long chain fatty acids; and polyhydric alcohols, in which the alcohol groups are free, omega-substituted polyethylene glycols of relatively long chain length. Granules comprise the herbicidal composition impreg¬ nated on a particulate inert carrier having a particle size of about 1 to 2 millimeters in diameter. The granules can be made by spraying a solution of the active ingredient in a volatile solvent onto the granular carrier. Suitable carriers in preparation of granules include clay, vermiculite, sawdust, granular carbon, etc. Microcapsules and other slow release formulations are advantageous as formulations to deliver and distribute the active ingredients. Microcapsules consist of fully enclosed droplets or granules containing the active materials in which the enclosing material is an inert porous membrane, arranged to allow escape of the enclosed materials to the surrounding medium at controlled rates over a specified period of time. Encapsulated droplets are typically about 1 to 50 microns in diameter. The enclosed liquid typically constitutes about 50 to 95% of the weight of the entire capsule, and may contain an amount of solvent in addition to the active materials. Encapsulated granules are characterized by porous membranes sealing the openings of the granule carrier pores, trapping the liquid containing the active components inside for con¬ trolled release. A typical granule size ranges from 1 milli¬ meter to 1 centimeter in diameter. In agricultural usage, the granule size is generally about 1 to 2 millimeters in diameter. Granules formed by extrusion, agglomeration or prilling are useful in the present invention as well as materials in their naturally occurring form. Examples of such carriers are vermiculite, starch sintered clay granules, kaolin, attapul- gite clay, sawdust and granular carbon. Useful encapsulating materials include natural and synthetic rubbers, cellulosic materials, styrene-butadiene copolymers, polyacrylonitriles, polyacrylates, polyesters, polyamides, polyureas, polyurethanes and starch xanthates. The herbicidal compositions can also be applied to the soil in the form of a solution in a suitable solvent. Solvents frequently used in herbicidal formulations include kerosene, fuel oil, xylene, petroleum fractions with boiling ranges above xylene, and aromatic petroleum fractions rich in methylated naphthalenes. E ulsifiable concentrates consist of an oil solution of the herbicide along with an emulsifying agent. Prior to use, the concentrate is diluted with water to form a suspended emulsion of oil droplets. The emulsifiers used are usually a mixture of anionic and nonionic surfactants. Other additives such as spreading agents and stickers can be included in the emulsifiable concentrate. .It is not necessary that the compositions be admixed with the soil particles. After application by the above- discussed methods, they may be distributed below the soil surface to a depth of at least one-half inch by conventional means such as discing, dragging, or mixing.

Claims: WHAT IS CLAIMED IS: 1. A synergistic herbicidal composition comprising: (a) An aryloxypropionic acid derivative of the formula in which X is hydrogen or halogen; R. is hydrogen, C.-C 8 alkyl, C.-C 8 alkoxyalkyl; and (b) a cyclohexanedione derivative of the formula in which R is independently hydrogen; halogen; nitro; cyano; C -C 8 alkyl; C.-C 8 alkyl substituted with a substituent selected from the group consisting of halogen, nitro, hydroxy, C -C 8 alkoxy and C.-Cg alkylthio; C 2 -C 8 alkenyl; C -C 8 alkynyl; hydroxy; C -C 8 alkoxy; C.-C 8 alkoxy substituted with a substi¬ tuent selected from halogen and C -C 8 alkoxy; C 2 ~C alkenyl- oxy; C 2 -C 8 alkynyloxy; C 2 -C alkanoyloxy; (C.-Cg alkoxy)- carbonyl; C.-C 8 alkylthio; C.-C 8 alkylsulfinyl; C.-Cg alkyl- sulfonyl; sulfamoyl; N-C( -C 8 alkyl)sulfamoyl; N,N-di(C.-C alkyl)sulfamoyl; benzyloxy, substituted benzyloxy wherein the benzene ring is substituted with from one to three substi¬ tuents selected from the group consisting of halogen, nitro, C.-C, alkyl, C.-C, alkoxy and C.-C, haloalkyl; the group NR 9R10 wherein R9 and R O are independently selected from the group consisting of hydrogen, C -Cg alkyl, 2 ~Cg alkanoyl, benzoyl emd benzyl; the groups formyl and -Cg alkanoxyl and the oxi e, imine and Schiff base derivatives thereof; and at least one of X is not selected from the group consisting of halogen, C.-C 8 alkyl and C.-Cg alkoxy; R 2 is C.-C, alkyl, C 2 -Cg alkenyl, C 2 -C 8 haloalkenyl, C 2 -C 8 alkynyl, C 2 -C 8 haloalkynyl, a substituted C.-Cg alkyl, substituted with halogen, C -C 8 alkoxy, C.-Cg alkylthio, phenyl, substituted phenyl wherein the phenyl is substituted with halogen, nitro, cyano, C.-Cg alkyl, c -C 8 haloalkyl, C.-C 8 alkoxy and C.-C 8 alkylthio; R_ is hydrogen, C -C 8 alkyl, C -Cg fluoroalkyl, C _«_:-Co, alkenyl, C«___-Co, alkynyl and phenyl; R. is hydrogen or the keto tautomer; .-Cg alkyl; C 2 -C 8 alkenyl; C 2 -C 8 alkynyl; substituted C.-Cg alkyl wherein the alkyl group is substituted with C.-C 8 alkoxy, C -Cg alkylthio, C.-C 8 alkoxycarbonyl, phenyl, and substituted phenyl wherein the benzene ring is substituted with 1 to 3 substituents selected from the group consisting of halogen, nitro, cyano, C.-C 8 alkyl, C.-C 8 haloalkyl, C.-C 8 alkoxy, and C.-C 8 alkylthio; C -Cg(alkyl) sulfonyl; benzene sulfonyl; substituted benzene sulfonyl wherein the benzene ring is substituted with 1 to 3 substituents selected from the group consisting of halogen, nitro, cyano, C.-C 8 alkyl, C.-C 8 haloalkyl, C.-Cg alkoxy and C -C 8 alkylthio; an acyl group and an inorganic or organic cation; and n is an integer chosen from 2 to 5. 2. A synergistic herbicidal composition comprising: (a) An aryloxypropionic acid derivative of the formula in which X is hydrogen or halogen; R. is: hhyyddrrooggeenn,, CC..--CC g g aallkk]yl, C.-Cg alkoxyalkyl; and (b) a cyclohexanedione of the formula in which R is formyl or C_-C, alkanoxyl; R 2 is C^ ^ -Cg alkyl; R, is C.-Cg alkyl; R. is hydrogen or the keto tautomer at a weight ratio of (a) to (b) of from about 1.0:0.001 to about 20:1. 3. A composition according to Claim 2 further comprising adjuvants. 4. A composition according to Claim 2 in which (a) is the D isomer of butyl 2-[4-(5-trifluoromethyl-2-pyridyloxy) phenoxy]-propionate. 5. A composition according to Claim 4 in which (b) is 2-[l-(ethoxyimino)propyl]-3-hydroxy-5-(2,4,6-trimethyl-3- butyrylphenyl)cyclohex-2-enone or the keto tautomer. 6. A composition according to Claim 4 in which (b) is 2-[1-(ethoxyimino)propyl]-3-hydroxy-5-(2,4,6-trimethyl-3- acetylphenyl)cyclohex-2-enone. 7. A composition according to Claim 2 in which X is hydrogen or chlorine and R. is hydrogen. 8. A composition according to Claim 7 in which R is acetyl or butyryl; R 2 and R_ are ethyl; R. is hydrogen or the keto tautomer. 9. A composition according to Claim 8 in which the weight ratio of (a) to (b) is from about 1:2 to about 8:1. 10. A composition according to Claim 9 further comprising adjuvants. 11. A synergistic herbicidal composition comprising: (a) A 5-trifluoro-substituted-2-pyridyloxy- phenoxy propionic acid derivative optionally substituted at the 3-position with halogen; and (b) a tetrasubstituted 5-phenyl-[2-(l-alkoxy- iminoalkyl) cyclohexanedione derivative at a weight ratio of (a) to (b) of about 1:2 to about 8:1. 12. A method of controlling undesirable vegetation which comprises applying to the locus where control is desired an herbicidal composition comprising a mixture of : (a) An aryloxypropionic acid derivative of the formula in which X is hydrogen or halogen; R. is hydrogen, C -C 8 alkyl, C. -C alkoxyalkyl; and (b) a cyclohexanedione of the formula in which R is formyl or C 2 -C 8 alkanoxyl; R 2 is C.-Cg alkyl; R 3 is ^-Cg alkyl; R. is hydrogen or the keto tautomer at a weight ratio of (a) to (b) of from about 1.0 to 0.001 to about 20:1. 13. A method according to Claim 12 wherein (a) is the D isomer of butyl 2-[4-(5-trifluoromethyl-2-pyridyloxy)- phenoxy]-propionate and (b) is 2-[l-(ethoxyimino)propyl]-3- hydroxy-5-(2,4,6-trimethyl-3-butyrylphenyl)cyclohex-2-enone or the keto tautomer. [received by the International Bureau on 5 January 1993 (05.01.93) ; original claim 1 amended; remaining claims unchanged (2 pages)] 1. A synergistic herbicidal composition comprising: (a) An aryloxypropionic acid derivative of the • formula in which X is hydrogen or halogen; R. is hydrogen, C 1 -C 8 alkyl, C 1 ~Cg alkoxyalkyl; and (b) a cyclohexanedione derivative of the formula in which R is independently hydrogen; halogen; nitro; cyano; C -C 8 alkyl; C.-C 8 alkyl substituted with a substituent selected from the group consisting of halogen, nitro, hydroxy, C^C alkoxy and C^Cg alkylthio; C 2 -Cg alkenyl; C 2 -C 8 alkynyl; hydroxy; C.-C 8 alkoxy; C.-Cg alkoxy substituted with a substi¬ tuent selected from halogen and C^Cg alkoxy; C 2 ~Cg alkenyl- oxy; C 2 -Cg alkynyloxy; C 2 -C 8 alkanoyloxy; C^Cg alkoxy)- carbonyl; C -C, alkylthio; C^Cg alkylsulfinyl; ^-Cg alkyl- sulfonyl; sulfamoyl; N-(C -C 8 alkyl)sulfamoyl; N,N-di(C 1 -C 8 alkyl)sulfamoyl; benzyloxy, substituted benzyloxy wherein the benzene ring is substituted with from one to three substi¬ tuents selected from the group consisting of halogen, nitro. C.-C, alkyl, C.-C, alkoxy and C.-C, haloalkyl; the group NR 9RΪO wherein R9 and RIO are independently selected from the group consisting of hydrogen, C -C 8 alkyl, C 2 -C 8 alkanoyl, benzoyl and benzyl; the groups formyl and C 2 -C 8 alkanoxyl and the oxime, imine and Schiff base derivatives thereof; R 2 is C.-C 8 alkyl, C 2 ~C alkenyl, C^-C, haloalkenyl, C 2 -Cg alkynyl, C 2 -C 8 haloalkynyl, a substituted C.-Cg alkyl, substituted with halogen, C.-Cg alkoxy, C.-C alkylthio, phenyl, substituted phenyl wherein the phenyl is substituted with halogen, nitro, cyano, C.-Cg alkyl, C.-Cg haloalkyl, C.-C 8 alkoxy and C.-C 8 alkylthio; R_ is hydrogen, C.-Cg alkyl, C -C 8 fluoroalkyl, C 2 -C 8 alkenyl, C 2 ~C g alkynyl and phenyl; R. is hydrogen or the keto tautomer; C.-C 8 alkyl; C 2 -C 8 alkenyl; C 2 -C 8 alkynyl; substituted C.-C 8 alkyl wherein the alkyl group is substituted with C.-C 8 alkoxy, C.-Cg alkylthio, C.-C alkoxycarbonyl, phenyl, and substituted phenyl wherein the benzene ring is substituted with 1 to 3 substituents selected from the group consisting of halogen, nitro, cyano, C.-C 8 alkyl, C.-C 8 haloalkyl, C.-C 8 alkoxy, and C.-C alkylthio; C -C 8 (alkyl) sulfonyl; benzene sulfonyl; substituted benzene sulfonyl wherein the benzene ring is substituted with 1 to 3 substituents selected from the group consisting of halogen, nitro, cyano, C.-Cg alkyl, C.-Cg haloalkyl, C.-C 8 alkoxy and C.-Cg alkylthio; an acyl group and an inorganic or organic cation; and n is an integer chosen from 2 to 5.

Inventors: ANDERSON JAMES, CASEY JOHN STEPHEN, COLBY S ROBERT, ANDERSON, JAMES, CASEY, JOHN, STEPHEN, COLBY, S., ROBERT
Applicants: ANDERSON JAMES, CASEY JOHN STEPHEN, COLBY S ROBERT, ANDERSON, JAMES, CASEY, JOHN, STEPHEN, COLBY, S., ROBERT
Application year: 1992
Main classification: A01N35
IPC codes: A01N43