FR2533804A1 - Herbicides based on bromoxynil trimethyl- or triethylamine salt. - Google Patents

Abstract

New herbicides. Trimethylamine and triethylamine salt of bromoxynil. They can be employed for selective antidicotyledon weeding of maize and sorghum.

Description

 The present invention relates to a novel weed control method in maize and sorghum crops, as well as new bromoxynil herbicides.

 It is known, for example from British Patent Nos. 1,030,249 and 1,067,032, that 3-dibromo-4-hydroxybenzonitrile (hereinafter referred to as "bromoxynil") as well as its esters and metal salts. alkaline, alkaline-earth, ammonium and amine, have interesting herbicidal properties, particularly for selective anti-dicotyledonous weeding in cereal crops, in post-emergence application ("post-emergence application"), This application is understood to mean the application to the aerial and exposed portion of dicotyledonous growths after emergence or emergence above the soil surface).

 Bromoxynil has been used for many years as a herbicide, mainly in the form of octanoate or alkali metal salt, particularly potassium salt, for the selective weeding of antidicotyl dones in cereal crops, post-emergence application. .

 Bromoxynil esters, especially octoctane, are widely used for selective post-emergence weed control, antidicotyledonous in cereal crops, particularly wheat, barley and oats with good efficacy, without significant phytotoxicity. on culture. However, the use of bromoxynil octanoate for postemergence weed control in relatively broad-leaved cereal crops, maize (Zea mays) and sorghum (Sorghum bicolor), has been restricted due to its phytotoxicity. transient on the culture, which manifests itself in the form of necrosis of the pulverized leaves. The margin of safety and thus of selectivity (ratio between the dose of application of a herbicide tolerated by the culture and that of the herbicide necessary for a destruction satisfactory weeds) octanoate is narrow.

 In marked contrast, bromoxynil octanoate exhibits a high selectivity coefficient in post-emergent antidicotyledon weeding on cereal crops such as wheat where it has been successfully used for several years.

 Alkaline and alkaline earth salts, particularly potassium salts, are tolerated by cereals and maize and sorghum at doses well above those of bromoxynil octanoate, but the achieved degree of antidicotyledone weed control is considerably lower and less reliable than with bromoxynil octanoate. This is why the potassium salt of bromoxynil was not used much alone for the weeding of cereals, whereas it was often used, post-emergence, in a mixture with other herbicides, on these same cultures.

 As a result, neither of the two bromoxynil drives, which have been previously widely used for selective anti-wart weed control of cereals, ie, the octanoate and the bromoxynil potassium salt, are used for selective weed control of maize and sorghum.

 Many amine salts of bromoxynil have been described as herbicides but none has so far been used extensively in agriculture.

It has now been found that the salts of trimethylamine and more especially of triethylamine (hereinafter referred to together as trimethyl- and triethylamine salts of bromoxynil ") are much more active in the weeding antidicotyledonous while being less phytotoxic vis-à-vis maize (Zea mays) and sorghum
(Sorghum bicolor) as bromoxynil octanoate. Consequently, the trimethyl- and triethylamine salts of bromoxynil, as defined above, have a selectivity margin or coefficient of selectivity much greater than that of bromoxynil octanoate in anti-cotyledon post-emergence herbicides. However, they are much more active, with a higher selectivity margin, for the same application, than the potassium salt of bromoxynil, which represents an important advance in this area. The trimethylanine and triethylamine salts of bromoxynil are also more active, with a margin of selectivity much greater than that of the other bromoxynil salts tested, for example the salts of triethanolanine, tri-n-propylamine, tri-n-butylamine, The salts of trimethyl- and triethylamine, the bronoxynil and more specifically the triethylamine salt, are satisfactorily supported by maize (zea mays) and sorghum.
(Sorghum bicolor) at application rates, in particular from 100 to 1000 g, and more particularly from 150 to 600 g of e.p. / hectare, for satisfactory control of dicotyledonous weeds in post-emergence. (By "ep" is meant, in the present description, phenol equivalent or the bromoxynil content of the trimethylamine or triethylamine salt of bromoxynil or other bromoxynil derivative).

Accordingly, the present invention provides a method of selective antidicotyledonous weed control in the raised maize (Zea mays) or sorghum (Sorghum bicolor) culture, which consists of post-emergence application to dicotyledon weeds in a corn crop or sorghum, an effective herbicidal amount, which does not cause damage to the culture, bromoxynil trimethylamine salt, or, preferably, triethylamine salt of bromoxynil, particularly at an application rate of 100 to 1000 g The bromoxynil trimethyl- and triethylamine salts can be used, according to the invention, to control the growth of dicotyledons Abutilon theophrasti, Amaranthus spp., and more especially from 150 to 600 g e.p./ hectare. for example Amaranthus retroflexus, Ambrosia artemisiifolia, Amsinkia intermedia,
Anchusa arvensis, Anthemis cotula, Ascelepias app., Aethusa cynapium, Atriplex Ratula, Brassica kaber, Brassica nigra,
Capsella bursa-pastoris, Centauria cyanus, Chenopodium album, Chorispora tenella, Datura stramonium, Descurainea sophia, Faqopyrum tartaricum, Galinso @ a parviflora,
Helianthus annuus, Ipomea spp., For example Ipomea @urpurea and Ipomea hederifolia, Kochia scoparia, Lapsana communis,
Lithospermum aryense, Matricaria recutita, Matricaria inodora, Myosotis arvensis, Papaver rhoeas, Plantago media,
Polygonum spp., For example Polygonum aviculare, Polygonum convolvulus, Polugonum lapathifolium, Polygonum persicaria,
Polygonum pensylyanicum and Polygonum scabrum, Portulaca oleracea, Raphanus raphanistrum, Senecio vulgaris, Sida spinosa, Silene alba, Sinapis arvensis, Solanum nigrum,
Solanum elaeagnifolium, Sonchus asper, Sonchus oleracea,
Thlaspi arvense, Veronica persica and Xanthium spp., For example Xanthium strumarium, Xanthium pensylvanicum and Xanthium cana @ ensis, postemergence in maize and sorghum crops, and more specifically for the control of Abutilon theophrasti, Amaranthus retroflexus,
Chenopodium album, Ipomea purpurea, Polygonum lapathifolium, Solanum nigrum and Xanthium strumarium, which are particularly difficult weeding problems for maize and sorghum.

 It is clear that to apply the dicotyledonous control method according to the invention, it is possible to use mixtures of the trimethylamine salt of bromoxynil and the bromoxynil triethylamine salt in any proportion.

 The trimethyl- and triethylamine salts of bromoxynil can be used alone postemergence against dicotyledonous weeds in maize and sorghum crops but can also be used in combination with herbicides and / or herbicides in application residual or pre-emergent or persistent, provided that they are tolerated by maize and sorghum. (By "residual application" and "pre-emergence application" is meant the application to the soil in which the seeds and shoots are present before emergence of these weeds above the soil surface). Suitable herbicides may be mention atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine), simazine [chloro-2-bis (ethylamino) 4,6-triazine-1,3,5], cyanazine [(chloro 4-ethylamino-6-triazine-1,3,5-ylamino-2-methyl-2-propionitrile, propazine [2-chloro-bis (isopropylamino) 4,6-triazine-1,3,5], the terbuthylazine (tert-butylamino-2-chloro-4-ethylamino-6-triazine 1,3,5), linuron [(3,4-dichlorophenyl) -3-dimethyl-1-ure], isoproturon [(4-isopropylphenyl) - Dinoseb acetate (2-sec-butyl-2,6-dinitro-4,6-phenol), dinoseb amine (alkylamine salts of sec-butyl-2-dinitro-4,6-phenol), dicamba (dichioro acid) 3,6, 2-methoxybenzoic acid) and its salts, for example sodium or potassium, or amines, by for example dimethylamine, and 2,4-phenoxyacetic acids (2,4-dichlorophenoxyacetic acid) and MCPA (2-methyl-4-chlorophenoxyacetic acid, for example sodium or potassium, or amines, for example alkylamines). such as monomethylamine, dimethylamine, isopropylamine or triethylamine, or alkanolamines, for example, diethanolamine, triethanolamine or mixtures of isopropylamines, or their low volatility esters, for example those of butoxyethanol, propylene glycol, tetrahydrofurfuryl alcohol, butoxypropanol, ethylhexanol or iso-octanol.

 The trimethyl- and triethylamine salts of bromoxynil can be used alone or in combination with the other herbicides indicated above for the antidicotyledon weeding of maize and sorghum crops post-emergence of both weeds and the crop. This treatment may possibly follow a pre-emergence or pre-plant treatment, possibly with incorporation into the soil, of maize and sorghum with at least one of the following herbicides: alachlor [chlo-ro-2-diethyl-2 ', 6'-N- ( methoxymethyl) acetanilide], metolachlor Ichloro-2-ethyl-6'-N- (2-methoxy-methyletnyl-1) acet-g-toluidine], pendimethaline [N- (1-ethylpropyl) 2,6-dinitroxylidine-3, 4] butylate (S-ethyl diisobutylthiocarbamate), vernolate (S-propyl dipropylthiocarbamate), EPTC (S-ethyl dipropylthiocarbamate), or a mixture (12: 1) of EPTC and N, N- diallyl 2,2-dichloroacetamide.

 For the fight against dicotyledonous weeds according to the invention, the trimethylamine and triethylamine salts of bromoxynil can be applied in the form of compositions comprising at least one of its salts in combination with, and preferably dispersed homogeneously in a or a plurality of compatible diluents or carriers acceptable for herbicides, i.e., diluents or carriers of the type generally recognized by those skilled in the art as being amenable to herbicide composition, and which are compatible with the trimethyl- and triethylamine salts of bromoxynil.

The term "homogeneously dispersed" allows to include those compositions for which the trimethyl- and triethylamine salts of bromoxynil are dissolved in the other components. The term "herbicidal compositions" is used in a broad sense, etc. not only the ready-to-use herbicidal compositions, but also the concentrates that must be applied before
employment.

The compositions preferably contain between
0.05 and 90% by weight of one or more trimethyl salts
and triethylamines of bromoxynil
The herbicidal compositions may contain at the
a diluent or carrier and a surfactant (eg a wetting, dispersing, or emulsifying agent).

The surfactants, which may be included in the herbicidal compositions of the present invention, may be of ionic or nonionic type, for example sulforicinoleates, quaternary ammonium derivatives, d-oxide condensate products, and the like. methylene with alkyl or polyaryl phenols, for example nonyl or octyl phenols, carboxylic acid esters and anhydrosorbitols rendered soluble by the etherification of free hydroxy groups by condensation with ethylene oxide, the salts alkali metal or alkaline earth metal esters of sulfuric and sulfonic acid esters, such as dinonyl- and dioctyl-sulfonosuccinates of sodiu-m, alkali metal or alkaline earth metal salts of tall sulfonic acid molecular weight, such as lignosulfates of sodium and calcium.

The compositions according to the invention may comprise from 0.01% to 10% of surfactant, but higher propottions may be used in particular in concentrated emulsifiable liquid suspensions (the
pro-portion can then go up to 15%) or in
soluble concentrates in water (the proportion can
then go up to 25%)
Examples of diluents or
suitable solid supports aluminum silicate,
talc, magnesia calcine, kieselguhr, phosphonate
tricalcium, cork powder, carbon black
absorbent, and clays such as kaolin or bentonite.

Solid compositions (which may be dusts, granules, or wettable powders) are preferably prepared by grinding bromoxynil trimethyl and triethylamine salts with solid diluents or by impregnating diluents or solid carriers with salt solutions. bromoxynil ttimethyl- and triethylamines in volatile solvents, followed by evaporation of the solvents and, if necessary, grinding of the products in order to obtain powders. Granular formulations are prepared by having bromoxynil trimethyl- and triethylamine salts (dissolved in volatile solvents) absorbed by diluents or solid supports in the form of granules, and then evaporating the solvents, or granulating them. the powder compositions obtained as described above. The solid herbicidal compositions, in particular the wettable powders, may contain wetting or dispersing agents (such as those mentioned above), which can also, in solid form, serve as diluents or supports.

 The liquid compositions according to the invention may be in the form of aqueous, organic or hydro-organic solutions, suspensions or emulsions which may contain a surfactant.

 Suitable liquid diluents in liquid compositions include water, glycols, tetrahydrofurfuryl alcohol, acetophenone, cyclohexanone, isophorone, toluene, xylene, and mineral oils (eg, light aromatic oil cups). or naphthenic), animal or vegetable (as well as some of these diluents). The surfactants which may be in the liquid compositions, are ionic or nonionic (for example of the types mentioned above) and may, in liquid form, also serve as diluents or carriers.

 Wettable powders and liquid compositions in the form of concentrates may be diluted in water or other suitable diluents, for example vegetable or mineral oils, particularly in the case of liquid concentrates, the diluent or carrier of which is oil, to give compositions ready for use.

If desired, the liquid compositions of the bromoxynil trimethyl- and triethylamine salts can be used as self-emulsifiable concentrates, in which the active ingredients are dissolved in emulsifying agents or in solvents containing zulsifiers compatible with the active ingredients the simple addition of water to these concentrates makes them ready for use.

 Liquid concentrates, for which the diluent, or carrier is an oil, are used without further dilution with the electrostatic spraying technique.

 The herbicidal compositions according to the present invention may also contain, if desired, conventional adjuvants such as adhesives, dyes, protective colloids, thickeners, penetrating agents, stabilizers, sequestering agents, anti-agglomeration agents, corrosion inhibitors and the like. conservatives. These adjuvants may also be used as carriers or diluents.

 The preferred herbicidal compositions according to the invention are wettable powders comprising, by weight, from 10 to 90% of at least one of the trimethyl- and triethylanines salts of bromoxynil, from 2 to 10% of a surfactant and of 10 to 88% of a diluent or solid support; solubilized liquid concentrates in water comprising, by weight / volume, from 5 to 50%, for example from 10 to 30%, of at least one of the bromoxynil trimethyl and triethylamine salts, from 5 to 25% by weight. a surfactant and 25 to 90% of a water-miscible solvent such as dimethylformamide or a miscible water-solvent mixture and the complement to 100% by volume of water; the granules comprising, by weight, from 1 to 90% of at least one of the bromoxynil trimethyl- and triethylamine salts, from 0.5 to 2.5% of a surfactant, from 7 to 98.5% of the total weight; a granular carrier of the emulsifiable concentrates comprising from 0.05% to 90% by weight / volume (preferably from 1 to 60% of bromoxynil trimethyl- and triethylamine salts), from 0.01 to 10% by weight / volume preferably 1 to 10% of surfactant and 9.99 to 99.4% and preferably 39 to 58.99% by volume of organic solvent.

 The herbicidal compositions according to the present invention may also comprise bromoxynil trimethyl and triethylamine salts in combination with, and preferably homogeneously partitioned into, one or more other pesticidally active compounds and, if desired, one or more diluents or compatible carriers acceptable for pesticides, surfactants, and customary adjuvants as mentioned above.

 The trimethylamine and triethylamine salts of bromoxynil can be prepared by writing, in stoichiometric amounts, bromoxynil and trimethylamine or triethylamine in a suitable inert solvent, for example a liquid diluent suitable for the liquid herbicidal compositions according to the invention, or mixtures, or a lower aliphatic alcohol, for example methanol or ethanol, or acetone, if necessary by heating. A stoichiometric amount of a mixture of trimethylamine and triethylamine may be used. The trimethyl- and triethylamine salts of bromoxynil or their mixtures may be isolated from the reaction medium by conventional methods, for example filtration, if necessary after partial elimination or complete solvent, for example by evaporation. However, it is currently more convenient to use the solution of trimethylamine and triethylamine salts of bromoxynil or mixtures thereof in a solvent that can be used directly in the preparation of the herbicidal compositions according to the invention, more particularly concentrated in water-miscible and wettable powders. without isolating the salts themselves. In this case, a slight excess of trimethylamine or triethylamine is preferably used alone or as a mixture, to give a solution of pH 8.5 to 9.5. Other constituents of the herbicidal compositions, for example surfactants in the solvent used for the preparation of the salts.

 The triethylamine salt of bromoxynil is a new compound which, along with its preparation process as well as the herbicidal compositions containing it, forms another aspect of the invention. When the herbicidal composition contains bromoxynil triethylamine salt and water or a common organic solvent, it is preferred to add a surfactant thereto.

 The following examples illustrate herbicidal compositions according to the invention.

1-1
A composition miscible with water is prepared. from, in weight / volume-:
bromoxynil 34% triethylamine 15%
tristyrylphenol condensate
with 18 moles of ethylene oxide
(surfactant) ... 1.5%
diethylene glycol 25%
water ............... qsp ........... 100% by volume
Part of the water is mixed with diethylene glycol, bromoxynil and triethylamine (15% of triethylamine represents an excess of 2.6% by weight relative to the stoichiometry of the triethylamine salt of bromoxynil) while heating with stirring . The surfactant is then added and the volume supplemented to 1003 with water. The resulting light brown liquid, pH 9, is completely miscible with water, and can be diluted with water and applied at a rate of 0 , 5 liter in 100 to 300 liters of spray liquid per hectare (ie an application rate of 170 g of bromoxynil ep: per hectare) to control the growth of dicotyledonous weeds, eg Theophrasti Abutilon, Amaranthus retroflexus, Cheno @ odium album, Ipomea pure @ urea, Polygonum lapathifolium, Solanum nigrum and Xanthium strumarium, in po-st raised on a crop raised maize or sorghum.

 An analogous water-miscible composition can be prepared by replacing triethylamine with trimethylamine.

Example 2
An emulsifiable composition is prepared from, by weight / volume
bromoxynil 34 *
triethylamine 12.4%
tristyrylpnenol condensate with
18 moles of ethylene oxide 5.25%
70% solution of dodecylbenzene
calcium sulphonate 7.5 z
Cyclohexanone 7.5% by volume
aromatic cut of oil in C10
qsp 100 X by volume
Cyclohexanone, bromoxynil and triethylamine and a portion of the aromatic solvent are mixed while heating with stirring. The two surfactants are then added and the volume is 100% complete with the solvent. The resulting light brown liquid is self-emulsifiable in water and can be diluted with water and applied at a rate of 1.5 100 1 to 300 1 of liquid spray per hectare (ie an application rate of 520 g of bromoxynil ep per hectare), to control the growth of dicotyledonous weeds, for example
Theophrasti, Amaranthus retroflexus, Chenopodium album, Ipomea purpurea, Polygonum lapathifolium, Solanum nigrum and Xanthium strumarium, post emergent on a raised maize or sorghum crop.

 An analogous emulsifiable composition can be prepared by replacing triethylamine with trimethylamine.

Example 3
The procedure is as in the preceding example except that the solvent portion is exclusively constituted by the aromatic solvent.

Example 4
A wettable powder is prepared from, by weight / volume:
bromoxynil 20%
triethylamine ... 8.8%
tristyrylphenol condensate
with 18 moles of 2.5% ethylene oxide
diethylene glycol 10%
aerosil (microfine silica) .. qsp. 100% by weight
Bromoxynil, triethylamine (8.8% is an excess of 2.5% relative to the stoichiometry for the bromoxynil triethylamine salt), surfactant and diethylene glycol are mixed with stirring until heated. to obtain a clear solution of pH 9. The aerosil is then stirred until the liquid is completely absorbed. A flowable powder is obtained which can be diluted with water and applied at the rate of 0.75 kg in 100 to 300 liters of liquid to be sprayed per hectare (ie a dose of 150 g of bromoxynil ep per hectare) to control the growth of dicotyledonous weeds, eg Abutilon theophrasti, Amaranthus retroflexus, Chenopodium album , Ipomea purpurea, Polygonum lapathifolium, Solanum niqrum and Xanthium strumarium, post emergent on a raised maize or sorghum crop.

 A similar wettable powder can be prepared by replacing triethylamine with trimethylamine.

Example 5
Water dispersible granules are prepared by careful mixing of the wettable powder containing the bromoxynil triethylamine salt obtained in Example 4 with water (up to 5% v / w) to obtain a hard paste which is then granulated by passage through an extruder and removal of excess water by drying. These granules are obtained which can be diluted with water and applied at the rate of 5 kg in 100 to 300 liters of liquid to be sprayed. hectare (ie a dose of 100 g of bromoxynil ep per hectare) to control the growth of dicotyledonous weeds, for example
Theophrasti, Amaranthus retroflexus, Chenopodium album, Ipomea purpurea, Polygonum lapathifolium, Solanum ni @ rum and Xanthium strumarium, post emergent on a raised maize or sorghum crop.

 A similar granule can be prepared by replacing triethylamine with trimethylamine.

A composition miscible with water, from ee, in weight / volume is prepared
bromoxynil 34%
trimethylamine 7.25%
tristyrylphenol condensate with
18 moles of ethylene oxide 1.25%
tetrahydrofurfuryl alcohol ... 25%
water qsp ... 100% in volume
One part of the water, tetrahydrofurfuryl alcohol and bromoxynil, is mixed together with stirring. The trimethylamine is then bubbled into the solution with the aid of a dip tube until a pH of 8 is obtained. The surfactant is then added and the volume is 100% complete with water. Resulting light brown is completely miscible with water and can be diluted with water and applied at the rate of 1 liter in 100 to 300 liters of liquid to be sprayed per hectare (ie a dose of 340 g of bromoxynil ep hectare) to control the growth of dicotyledonous weeds, for example theophyllus Abutilon, Amaranthus retroflexus, Chenopodium album, Ipomea purpurea, Polygonum lapathifolium, Solanum ni @ rum and Xanthium strumarium, post emergent on a raised maize or sorghum crop.

Example 7
An emulsifiable composition is prepared from, by weight / volume
bromoxynil 34%
trimethylamine 7.25%
Condensate t of tristyrylphenol with
18 moles of ethylene oxide ...... 3.75%
Calcium dodecylbenzenesulfonate 3.75%
1: 1 mixture of cyclohexanone and
of aromatic solvent
(cut in C10) ......... qsp ...... 100% in volume
Bromoxynil and a portion of the solvent mixture are mixed while heating with stirring. The trimethylamine is then bubbled into the solution with the aid of a dip tube until the bromoxynil is dissolved. The surfactants are then added and the volume is 100% complete with the solvent mixture. The resultant light brown liquid is self-emulsifiable in water and can be diluted with water and applied, at the rate of 1 liter in 100 to 300 liters of liquid to be sprayed per hectare (ie a dose of 340 g of bromoxynil ep per hectare) to control the growth of dicotyledonous weeds, eg Theophrasti Abutilon, Amaranthus retroflexus,
Chenopodium album, Ipomea purpurea, Polygonum lapathlfolium, Solanum nigrum and Xanthium strumarium, post-emergent on a raised maize or sorghum crop.

A water-miscible composition is prepared from, by weight / volume
bromoxynil 34%
triethylamine 15%
tristyrylphenol condensate
with 18 moles of ethylene oxide
(surfactant) 1.5%
tetrahydrofurfuryl alcohol ... 25%
water ............... qsp ........... 100% by volume
Some of the water is mixed, tetrahydrofurfuryl alcohol, bromoxynil and triethylamine
(15% of triethylamine represents an excess of 2.6% by weight relative to the stoichiometry of bromoxynil triethylamine salt) while heating with stirring. The t-ensio-active is then added and the volume is 100% complete with water. The resulting light brown liquid, pH 9, is completely miscible with water, and can be diluted with water and applied to water. 0.5 liter in 100 to 300 liters of liquid spray per hectare
(ie an application rate of 1.70 g bromoxynil ep per hectare) to control the growth of dicotyledonous weeds, eg Theophr Amaranthus retroflexus Abutilon, Chenopodium album, Ipomea pure @
Polygonum lapathifolium, Solanum nigrum and Xanthium trumarium, post emergent on a raised maize or sorghum crop.

Example 9
An emulsifiable composition is prepared from, by weight / volume
bromoxynil 34%
triethylamine 12.4%
Condensate of tristyrylphenol with
18 moles of ethylene oxide 3.75%
Calcium dodecylbenzenesulfonate 3.75%
1: 1 mixture of cyclohexanone and
aromatic solvent (C10 cut) qs 100 * by volume
Bromoxynil and a portion of the solvent mixture are mixed while heating with stirring. The trimethylamine is then bubbled into the solution with the aid of a dip tube until the bromoxynil is dissolved. The surfactants are then added and the volume supplemented to 100% with the solvent mixture. The resulting light brown liquid is self-emulsifiable in water and can be diluted with water and applied at a rate of 1.5 liter in 100 to 300 liters of spray liquid per hectare (equivalent to 510 g of bromoxynil ep per hectare) to control the growth of dicotyledonous weeds, for example, Abutilon theophrasti, Amaranthus retroflexus,
Chenopodium album, Ipomea purpurea, Poly @ onum lapathifolium, Solanum nigrum and Xanthium strumarium, post emergent on a raised maize or sorghum crop.

 The method of controlling weed growth according to the invention and the advantageous selectivity of the trimethyl and triethylamine salts of bromoxynil on maize and sorghum crops in post-emergence treatment, compared to that of bromoxynil derivatives widely used as octanoate and potassium salt and other amine salts are shown by the following tests.

The following formulations are tested
A: the water-miscible composition of Example 1
B: the emulsifiable composition of Example 3
C: the emulsifiable composition of Example 2
D: the water-miscible composition of Example 1
E: the emulsifiable composition of Example 2
F: a composition miscible with water containing 25%
(ep) by weight of the potassium salt of the
bromoxynil, 1.1% by weight of condensate
tristyrylphenol with 18 moles of ethylene oxide,
40% tetrahydrofurfuryl alcohol and the supplement
100% water by volume, is prepared as
Example 1, replacing the triethylamine salt of
bromoxynil and diethylene glycol in amounts
appropriate respectively potassium salt of the
bromoxynil and tetrahydrofurfuryl alcohol.

G: a commercially available emulsiomnable composition containing
22.5% (ep) by weight / volume of octanoate
bromoxynil, 7.5% of a surfactant combination
ATLOX 4855, Agrilan A and the complement at 100 *
in volume of a high-point oil cup
boiling point, is prepared as in Example 2.

(ATLOX 4855 and Agrilan A are both blends
of a nonionic surfactant and
calcium dodecylbenzenesulfonate).

 Sow in a greenhouse in 13 cm diameter plastic pots containing John Innes No. 1 potting compost (7 volumes of sterilized soil, 3 peat volumes and 2 volumes of fine sand) of the corn seeds (zea mays ), sorghum (sorqhum bicolor) and wheat (Triticum sativum).

 Weed and crop shoots, grown in greenhouses, are transplanted into plastic pots, 6 cm in diameter, containing John Innes No. 1 potting compost, at a rate of 3 shoots per pot. The average greenhouse temperature varies from 150C at night to 270C during the day with 16 hours of day. Three repetitions are used per treatment. We keep pots without treatment as witnesses. The following plants are used with their stage of cure.

Plants Leaves
corn 4
sorghum 3 1/2 wheat 3
dicotyledonous weeds
Amaranthus retroflexus (Ar) 3
Polygonum lapathifolium (Pl) 3
Ipomea purpurea (IP) 3
Chenopodium album (Ca) 4
Solanum nigrum (Sn) 4
Xanthium strumarium (x s.) 4
Abutilon theophrasti (At) 3
Appropriate amounts of formulations A to G are diluted in 50 ml of water. Spray liquids are obtained at concentrations equivalent to 85, 170, 340, 680 and 1360 g (ep) of bromoxynil per hectare for a spray volume of 260 liters per hectare. The treatments are carried out with a flat-bladed laboratory sprayer (pressure: 2.1 kgf / cm2) moving at 2.6 km / h. The plants are watered 24 hours after spraying, then every day. After 10 days after spraying, control is made visually of the percentage reduction in the height of each shoot, compared to that of the control shoots. The average percentage reduction is calculated. The results are shown in Table 1 below.

The phytotoxicity assessment of maize, sorghum and wheat is similar but as a percentage of necrosis of the whole plant. The results are given in Table 2 below.
The dose of each of the A to G formulations required to cause 95% kill on all of the weed species is calculated by plotting the overall kill on a log paper. These doses causing 95% destruction are noted in Table 3 below. This clearly shows that the trimethylamine and triethylamine salts of bromoxynil are 3 to 5 1/2 times more active than the bromoxynil potassium salt on weeds and, unlike the latter, are at least equal to or worse, only 1.8 times less active than bromoxynil octanoate.

 The doses of each of the formulations A to G giving no more than 5% phytotoxicity (foliar necrosis) on the crops (maize, sorghum and wheat) are calculated analogously from the results of Tables 2 and 3.

 The selectivity coefficient: dose causing no more than 5% phytotoxicity on the dose culture causing 95% destruction of all weeds is calculated from these results for each formulation on each crop and these indices are recorded in the table below. Table 3. These results clearly show that the bromoxynil trimethylamine and triethylamine salts in post-emergence treatment are, compared to the bromoxynil octanoate, from 2 to 5 1/2 times more selective on corn, from 2 1/4 to 6 1/2 times more selective on sorghum, and on maize and sorghum, three times more active on weeds.

 These selectivity coefficients also show that the trimethylanine and triethylamine salts of bromoxynil are very selective on wheat but that, unlike their selectivity index on corn and sorghum, they do not have any advantages over the octanoate of bromoxynil for anti-dicotyledon weed control post-emergence of wheat.

you; 2
The following formulations are tested
H: the water-miscible composition of Example 6.

 I: the emulsifiable composition of Example 7.

 J: the water miscible composition of Example 8.

 K: the emulsifiable composition of Example 9.

L: the water-miscible composition of Example 8 in
which triethylamine is replaced by
triethanolamine in a stoichiometric amount.

M: the emulsifiable composition of Example 9 in
which triethylamine is replaced by sorting
n-propylamine in stoichiometric amount.

N: the emulsifiable composition of Example 9 in
which triethylamine is replaced by sorting
n-butylamine in stoichiometric amount.

O: the emulsifiable composition of Example 9 in
which triethylamine is replaced by
N-methyl-n-octylamimide in stoichiometric amount.

P: the water-miscible composition of Example 8 in
which triethylamine and bromoxynil are
replaced by the potassium salt of bromoxynil
stoichiometric amount.

Q: The water-miscible composition of Example 8 in
which triethylanine is replaced by
aqueous ammonia concentrated in quantity
stoichiometric.

R: the emulsifiable composition of Example 9 in
which triethylamine and bromoxynil are
replaced by a stoichiometric quantity
of bromoxynil octanoate.

Maize, sorghum and dicotyledonous weeds are sown as in test 1. The shoots are sprayed at the next stage
Crops Leaves
Corn 3
Sorghum 3
weed
Ipomea purpurea (Ip) Cotyledons + 1 true leaf
Abutilon theophrasti (At) """
Amaranthus retroflexus (Ar) 2
Chenopodium album (Ca) 4
Suitable amounts of formulation H to R are diluted in 50 ml of water. Spray liquids are obtained at concentrations equivalent to 85, 170, 340, 680 and 1360 g (ep) of bromoxynil per hectare for a spray volume of 260 liters per hectare. The treatments are carried out with a flat jet laboratory sprayer (pressure: 2.1 kgf / cm2) moving at 2.6 km / hour. The plants are sprayed with 24 neurons after spraying, and then daily. After 10 days after spraying, the control of the percentage reduction in the height of each shoot is visually compared to that of the lesser shoots. The average percentage reduction is calculated. The results are shown in Table 4 below,
The phytotoxicity of corn, sorghum and wheat is assessed as a percentage of necrosis of the whole plant. The results are shown in Table 5 below.

 The dose of each of the formulations H to R required to cause 95% destruction on all of the weed species is calculated as in test 1. All these doses are recorded in Table 6 below. It clearly shows that the trimethylamine and triethylainine salts of bromoxynil are post-emergent antidicotyledon weed control, more active than the trietbanolamine, tri-n-propylamine, tri-n-butylamine and methyl-di salts. n-octylamine, 3 1/2 to 4 times more active than potassium salt and 2 to 3 times more active than ammonium salt.The salts of trimethylamine and triethylamine bromoxynil have a higher level of activity. octanoate than other bromoxynil salts, in particular Potassium salt and ammonium salt, while at the same time being only at least one active dwarf than octanoate, whereas on the contrary the salt of potassium and ammonium salt are respectively 5 1/2 and 4l times less active than octanoate.

 The doses of each of the formulations B to R required not to cause more than 5% phytotoxicity (foliar necrosis) on the crops (maize and sorghum) were calculated from the results of Table 5 and are recorded in Table 6. The selectivity coefficient is calculated from these results for each formulation on each culture and these indices are also recorded in Table 6. These results clearly show that the salts of trimethylamine and triethylamine are very selective on maize and sorghum. , unlike the triethanolamine, tri-n-propylamine, tri-m-butylamine, methyl-di-n-octylamime, ammonium and potassium salts and bromoxynil octanoate. The selectivity coefficient shows in treatment post-emergence antidicotyledones that the triethylamine and triethylamine salts of bromoxynil are, relative to octanoate, 2.5 to 3 times more selective on maize and 2.8 to 3.1 times higher lectifs on sorghum. This coefficient of selectivity also shows that the triethanolamine, tri-n-propylamine, tri-n-butylamine, methyl-di-n-octylamine, ammonium and potassium salts do not have an advantage in selectivity with respect to octanoate for post-emergence weed control of cotton and sorghum.

Example 10
Preparation of trimethyl- and triethylamine salts of bromoxynil

 5.5 ml of triethylamine was added to a stirred solution of dibromo-3,5-hydroxy-4-benzonitrile (5.54 g) in acetone (40 ml). After 10 minutes, at the end of the exothermic reaction, the mixture is filtered and the filtrate evaporated to dryness to give a solid. This is triturated with ethyl acetate and separated by filtration to give the triethylamine salt of bromoxynil (which may also be called 2,6-dibromo, triethylammonium cyano-4-phenolate) (5.1 g) as a cream colored solid, mp 56-580 ° C.

Elemental analysis for C13 H18 Br2 N2O% CHN
Calculated 41.30 4.76 7.40
Found 41.20 4.80 7.30
Working in the same way but n replacing triethylamine with trimethylamine and acetone with alcohol, the salt of trimethylamine bromoxynil (which can also be called 2,6-dibromo, cyano-4-phenolate) is obtained. trimethylammonium), in the form of a cream colored solid, with a melting point of 97-99 ° C.
Elemental analysis for C10 H12 Br2 N 20
% CHN
Calculated 35.7 3.6 8.3
Found 35.3 3.4 7.6
Dibromo-3,5-hydroxy-4-benzonitrile (bromoxynil) can be prepared as described by Auwers and Reis, Ber., 29 (2), 2355-2360 (1896).

TABLE 1

Formulation
<tb> dose <SEP>% <SEP> average <SEP> of <SEP> destruction
<tb> [Bromoxynil <SEP> of <SEP> species <SEP> of weeds
<tb> g (ep) / ha] SEP> Ca <SEP> Pl <SEP> At <SEP> Ar <SEP> Xs <SEP> lp <SEP> Sn <SEP> together
<tb> (all <SEP> species)
<tb> A <SEP> 85 <SEP> 33 <SEP> 100 <SEP> 83 <SEP> 100 <SEP> 60 <SEP> 70 <SEP> 100 <SEP> 78
<tb> (Salt <SEP>) of <SEP> triethyl- <SEP> 170 <SEP> 85 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 98
<tb> amine <SEP> of <SEP> 340 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> bromoxynil) <SEP> 680 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> 1360 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> B <SEP> 85 <SEP> 40 <SEP> 100 <SEP> 75 <SEP> 100 <SEP> 53 <SEP> 80 <SEP> 100 <SEP> 78
<tb> (Salt <SEP>) of <SEP> triethyl- <SEP> 170 <SEP> 90 <SEP> 100 <SEP> 83 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 96
<tb> amine <SEP> of <SEP> 340 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> bromoxynil) <SEP> 680 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> C <SEP> 85 <SEP> 23 <SEP> 80 <SEP> 80 <SEP> 100 <SEP> 80 <SEP> 80 <SEP> 97 <SEP> 77
<tb> (Salt <SEP>) of <SEP> triethyl- <SEP> 170 <SEP> 50 <SEP> 100 <SEP> 80 <SEP> 100 <SEP> 100 <SEP> 80 <SEP> 100 <SEP> 87
<tb> amine <SEP> of <SEP> 340 <SEP> 97 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 99.5
<tb> bromoxynil) <SEP> 680 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> 1360 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> TABLE 1 (Continued)

Formulation
<tb> dose <SEP>% <SEP> average <SEP> of <SEP> destruction
<tb> [Bromoxynil <SEP> of <SEP> species <SEP> of weeds
<tb> g (ep) / ha] SEP> Ca <SEP> Pl <SEP> At <SEP> Ar <SEP> Xs <SEP> Ip <SEP> Sn <SEP> together
<tb> (all <SEP> species)
<tb> D <SEP> 85 <SEP> 10 <SEP> 90 <SEP> 47 <SEP> 100 <SEP> 40 <SEP> 50 <SEP> 100 <SEP> 62
<tb> 170 <SEP> 62 <SEP> 100 <SEP> 70 <SEP> 100 <SEP> 85 <SEP> 90 <SEP> 100 <SEP> 87
<tb> (Sel <SEP> of <SEP> tri- <SEP> @
<tb> 340 <SEP> 97 <SEP> 100 <SEP> 90 <SEP> 100 <SEP> 90 <SEP> 100 <SEP> 100 <SEP> 97
<tb> methylamine
<tb> 680 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> of <SEP> bromoxynil)
<tb> 1360 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> E <SEP> 85 <SEP> 33 <SEP> 93 <SEP> 80 <SEP> 90 <SEP> 35 <SEP> 70 <SEP> 100 <SEP> 72
<tb> 170 <SEP> 73 <SEP> 100 <SEP> 83 <SEP> 100 <SEP> 60 <SEP> 75 <SEP> 100 <SEP> 84
<tb> (Salt <SEP> of <SEP> tri340 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 93 <SEP> 100 <SEP> 100 <SEP> 99
<tb> methylamine
<tb> 680 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> of <SEP> bromoxynil
<tb> 1360 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> F <SEP> 85 <SEP> 0 <SEP> 30 <SEP> 45 <SEP> 80 <SEP> 10 <SEP> 10 <SEP> 50 <SEP> 32
<tb> 170 <SEP> 0 <SEP> 75 <SEP> 80 <SEP> 90 <SEP> 40 <SEP> 40 <SEP> 80 <SEP> 58
<tb> (Salt <SEP> of <SEP> potassium
<tb> 340 <SEP> 45 <SEP> 97 <SEP> 90 <SEP> 100 <SEP> 70 <SEP> 70 <SEP> 90 <SEP> 80
<tb> (from <SEP> Bromoxynil)
<tb> 680 <SEP> 90 <SEP> 100 <SEP> 90 <SEP> 100 <SEP> 90 <SEP> 80 <SEP> 100 <SEP> 93
<tb> 1360 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> TABLE 1 (Continued)

Formulation <SEP>% <SEP> average <SEP> of <SEP> destruction
<tb> [Bromoxynil <SEP> of <SEP> species <SEP> of weeds
<tb> g (ep) / ha] SEP> Ca <SEP> Pl <SEP> At <SEP> Ar <SEP> Xs <SEP> Ip <SEP> Sn <SEP> together
<tb> (all <SEP> species)
<tb> G <SEP> 85 <SEP> 45 <SEP> 93 <SEP> 90 <SEP> 100 <SEP> 80 <SEP> 80 <SEP> 90 <SEP> 83
<tb> 170 <SEP> 80 <SEP> 100 <SEP> 97 <SEP> 100 <SEP> 97 <SEP> 93 <SEP> 100 <SEP> 95
<tb> (Octanoate
<tb> 340 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> from <SEP> Bromoxynil)
<tb> 680 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> 1360 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> TABLE 2

Formulation <SEP> surface <SEP> foliar <SEP> necrotic
<tb> culture <SEP> dose <SEP> [Bromoxynil <SEP> g <SEP> (ep) / ha]
<tb> 85 <SEP> 170 <SEP> 340 <SEP> 680 <SEP> 1360
<tb> A <SEP> Corn <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0
<tb> (Salt <SEP> of <SEP> triethylamine <SEP> Sorghum <SEP> 0 <SEP> 0 <SEP> 0 <SEP><5<SEP> 6
<tb> of <SEP> bromoxynil) <SEP> Wheat <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0
<tb> B <SEP> Corn <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP><5
<tb> (Salt <SEP> of <SEP> triethylamine <SEP> Sorghum <SEP> 0 <SEP> 0 <SEP><5<SEP> 5 <SEP> 18
<tb> of <SEP> bromoxynil) <SEP> Bie <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0
<tb> C <SEP> Corn <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 5
<tb> (Salt <SEP> of <SEP> triethylamine <SEP> Sorghum <SEP> 0 <SEP> 0 <SEP> 0 <SEP><5<SEP> 20
<tb> of <SEP> bromoxynil) <SEP> Bie <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0
<tb> D <SEP> Corn <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP><5
<tb> (Salt <SEP>) of <SEP> trimethylamine <SEP> Sorghum <SEP> 0 <SEP> 0 <SEP><5<SEP> 5 <SEP> 15
<tb> of <SEP> bromoxynil) <SEP> Wheat <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0
<tb> TABLE 2 (Continued)

Formulation <SEP> Surface <SEP> foliar <SEP> necrotic
<tb> culture <SEP> dose <SEP> [Bromoxynil <SEP> g (ep) / ha]
<tb> 85 <SEP> 170 <SEP> 340 <SEP> 680 <SEP> 1360
<tb> E <SEP> Corn <SEP> 0 <SEP> 0 <SEP> 0 <SEP><5<SEP> 10
<tb> (Salt <SEP> of <SEP> triethylamine <SEP> Sorghum <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 5 <SEP> 15
<tb> of <SEP> bromoxynil <SEP> Wheat <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP><5
<tb> F <SEP> Corn <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP><5
<tb> (Salt <SEP> of <SEP> potassium <SEP> Sorghum <SEP> 0 <SEP> 0 <SEP> 0 <SEP><5<SEP> 10
<tb> of <SEP> bromoxynil) <SEP> Wheat <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0
<tb> G <SEP> Corn <SEP> 0 <SEP><5<SEP> 8 <SEP> 17 <SEP> 60
<tb> (Octanoate <SEP> of <SEP> Sorghum <SEP> 0 <SEP> 5 <SEP> 7 <SEP> 23 <SEP> 42
<tb> bromoxynil) <SEP> Wheat <SEP> 0 <SEP> 0 <SEP> 0 <SEP><5<SEP><5
<tb>("<" means "less than") TABLE 3

Formulation
<tb> Dose <SEP> causing <SEP><SEP> Dose <SEP><SEP> causing <SEP> not
<tb> destruction <SEP> at <SEP> 95 <SEP>% <SEP> more <SEP> of <SEP> 5 <SEP>% <SEP> of <SEP> phytode <SEP> the <SEP> set of <SEP> toxicity <SEP> (necrosis <SEP> fo- <SEP> Index <SEP> of <SEP> selectivity
<tb> weeds <SEP> liaire) <SEP> on <SEP> the <SEP> culture
<tb> [Bromoxynil <SEP> [Bromoxynil <SEP> g <SEP> (ep) / ha]
<tb> g <SEP> (ep) / ha] <SEP> 2
<tb> Corn <SEP> Sorghum <SEP> Wheat <SEP> Corn <SEP> Sorghum <SEP> Wheat
<tb> A
<tb> (Salt <SEP>) of <SEP> triethyl- <SEP> 130 <SEP>> 1360 <SEP> 1020 <SEP>> 1360 <SEP>> 10 <SEP> 7.8 <SEP>> 10
<tb> amine <SEP> of
<tb> bromoxynil)
<tb> B
<tb> (Salt <SEP>) of <SEP> triethyl- <SEP> 140 <SEP>> 1360 <SEP> 680 <SE>> 1360 <SEP>> 9.7 <SEP> 4.8 <SEP>> 9.7
<tb> amine <SEP> of
<tb> bromoxynil)
<tb> C
<tb> (Salt <SEP> of <SEP> triethyl- <SEP> 190 <SEQ> 1360 <SEP> 680 <SEA>> 1360 <SEP> 7.1 <SEP> 3.6 <SEP>> 7.1
<tb> amine <SEP> of
<tb> bromoxynil)
<tb> TABLE 3 (Continued)

Formulation
<tb> Dose-causing <SEP><SEP> Dose <SEP> not <SEP> causing <SEP> not
<tb> destruction <SEP> at <SEP> 95 <SEP>% <SEP> more <SEP> of <SEP> 5 <SEP>% <SEP> of <SEP> phytode <SEP> the <SEP> set of <SEP> toxicity <SEP> (necrosis <SEP> fo- <SEP> Index <SEP> of <SEP> selectivity
<tb> weeds <SEP> liaire) <SEP> on <SEP> the <SEP> culture
<tb> [Bromoxynil <SEP> [Bromoxynil <SEP> g <SEP> (ep) / ha]
<tb> g <SEP> (ep) / ha]
<tb> Corn <SEP> Sorghum <SEP> Wheat <SEP> Corn <SEP> Sorghum <SEP> Wheat
<tb> D
<tb> (Salt <SEP> tetramethyl- <SEP> 250 <SE>>> 1360 <SEP> 680 <SE>> 1360 <SEP>> 5.4 <SEP> 2.7 <SEP>> 5.4
<tb> amine <SEP> of
<tb> bromoxynil)
<tb> E
<tb> (Salt <SEP> tetramethyl- <SEP> 235 <SEP> 900 <SEP> 680 <SE>> 1360 <SEP> 3.8 <SEP> 2.9 <SE>> 5.8
<tb> amine <SEP> of
<tb> bromoxynil)
<tb> F
<tb> (Salt <SEP> of <SEP> potassium <SEP> 720 <SE>>> 1360 <SEP> 1020 <SE>> 1360 <SEP>> 1.9 <SEP> 1.4 <SEP>> 1.9
<tb> of <SEP> bromoxynil)
<tb> G
<tb> (Octanoate <SEP>) of the <SEP> 140 <SEP> 250 <SEP> 170 <SEP> 1360 <SEP> 1.8 <SEP> 1.2 <SEP> 9.7
<tb> bromoxynil)
<tb>(">" means "greater than") TABLE 4

Formulation
<tb> Dose <SEP>% <SEP> Medium <SEP> of <SEP> Destruction
<tb> [Bromoxynil <SEP> of <SEP> species <SEP> of weeds
<tb> g (ep) / ha] <SEP> Ip <SEP> At <SEP> Ar <SEP> Ca <SEP> together
<tb> (all <SEP> species)
<tb> H <SEP> 85 <SEP> 50 <SEP> 10 <SEP> 10 <SEP> 10 <SEP> 20
<tb> (Salt <SEP>) <SEP> trimethyl- <SEP> 170 <SEP> 95 <SEP> 70 <SEP> 30 <SEP> 62 <SEP> 64
<tb> amine <SEP> of <SEP> 340 <SEP> 100 <SEP> 95 <SEP> 90 <SEP> 95 <SEP> 95
<tb> bromoxynil) <SEP> 680 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> 1360 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> I <SEP> 85 <SEP> 75 <SEP> 35 <SEP> 30 <SEP> 35 <SEP> 42
<tb> (Salt <SEP>) of <SEP> trimethyl- <SEP> 170 <SEP> 100 <SEP> 75 <SEP> 60 <SEP> 75 <SEP> 78
<tb> amine <SEP> of <SEP> 340 <SEP> 100 <SEP> 95 <SEP> 95 <SEP> 95 <SEP> 96
<tb> bromoxynil) <SEP> 680 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> 1360 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> J <SEP> 85 <SEP> 85 <SEP> 30 <SEP> 40 <SEP> 35 <SEP> 47
<tb> (Salt <SEP> of <SEP> sorted) <SEP> 170 <SEP> 100 <SEP> 60 <SEP> 70 <SEP> 70 <SEP> 75
<tb> thylamine <SEP> of <SEP> 340 <SEP> 100 <SEP> 95 <SEP> 100 <SEP> 95 <SEP> 97
<tb> Bromoxynil) <SEP> 680 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> 1360 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> TABLE 4 (Continued)

Formulation
<tb> Dose <SEP>% <SEP> Medium <SEP> of <SEP> Destruction
<tb><SEP> species <SEP> of weeds
<tb> [Bromoxynil
<tb> g (ep) / ha] <SEP> Ip <SEP> At <SEP> Ar <SEP> Ca <SEP> Together
<tb> (all <SEP> species)
<tb> K <SEP> 85 <SEP> 95 <SEP> 40 <SEP> 43 <SEP> 50 <SEP> 57
<tb> (Salt <SEP>) of <SEP> triethyl170 <SEP> 100 <SEP> 70 <SEP> 80 <SEP> 100 <SEP> 87
<tb> amine <SEP> of
<tb> 340 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> bromoxynil)
<tb> 680 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> 1360 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> L <SEP> 85 <SEP> 60 <SEP> 20 <SEP> 10 <SEP> 20 <SEP> 27
<tb> (Sel <SEP> of <SEP> trietha- <SEP> 170 <SEP> 90 <SEP> 40 <SEP> 40 <SEP> 75 <SEP> 61
<tb> nolamine <SEP> of <SEP> 340 <SEP> 100 <SEP> 85 <SEP> 70 <SEP> 95 <SEP> 87
<tb> bromoxynil) <SEP> 680 <SEP> 100 <SEP> 100 <SEP> 95 <SEP> 100 <SEP> 99
<tb> 1360 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> M <SEP> 85 <SEP> 60 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 15
<tb> (Sel <SEP> of <SEP> tri-n <SEP> 170 <SEP> 95 <SEP> 10 <SEP> 20 <SEP> 60 <SEP> 46
<tb> propylamine <SEP> of <SEP> 340 <SEP> 100 <SEP> 35 <SEP> 65 <SEP> 80 <SEP> 70
<tb> bromoxynil) <SEP> 680 <SEP> 100 <SEP> 80 <SEP> 100 <SEP> 100 <SEP> 95
<tb> 1360 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> TABLE 4 (Continued)

Formulation
<tb> Dose <SEP>% <SEP> Medium <SEP> of <SEP> Destruction
<tb> [Bromoxynil <SEP> of <SEP> species <SEP> of weeds
<tb> g (ep) / ha] <SEP> Ip <SEP> At <SEP> Ar <SEP> Ca <SEP> Together
<tb> (all <SEP> species)
<tb> N <SEP> 85 <SEP> 43 <SEP> 20 <SEP> 0 <SEP> 20 <SEP> 21
<tb> (Salt <SEP> of <SEP> tri-n- <SEP> 170 <SEP> 100 <SEP> 45 <SEP> 30 <SEP> 70 <SEP> 61
<tb> butylamine <SEP> of <SEP> 340 <SEP> 100 <SEP> 80 <SEP> 65 <SEP> 100 <SEP> 86
<tb> bromoxynil) <SEP> 680 <SEP> 100 <SEP> 95 <SEP> 100 <SEP> 100 <SEP> 98
<tb> 1360 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> O <SEP> 85 <SEP> 40 <SEP> 10 <SEP> 10 <SEP> 30 <SEP> 33
<tb> (Salt <SEP> of <SEP> methyl- <SEP> 170 <SEP> 100 <SEP> 30 <SEP> 30 <SEP> 70 <SEP> 57
<tb> di-n-octylamine <SEP> 340 <SEP> 100 <SEP> 60 <SEP> 50 <SEP> 100 <SEP> 77
<tb> of <SEP> bromoxynil) <SEP> 680 <SEP> 100 <SEP> 98 <SEP> 100 <SEP> 100 <SEP> 99
<tb> 1360 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> P <SEP> 85 <SEP> 20 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 5
<tb> (Salt <SEP> of <SEP> potassium
<tb> 170 <SEP> 40 <SEP> 10 <SEP> 10 <SEP> 20 <SEP> 20
<tb> of <SEP> bromoxynil)
<tb> 340 <SEP> 100 <SEP> 20 <SEP> 30 <SEP> 50 <SEP> 50
<tb> 680 <SEP> 100 <SEP> 50 <SEP> 60 <SEP> 90 <SEP> 75
<tb> 1360 <SEP> 100 <SEP> 90 <SEP> 100 <SEP> 100 <SEP> 97
<tb> TABLE 4 (Continued)

Formulation
<tb> Dose <SEP>% <SEP> Medium <SEP> of <SEP> Destruction
<tb> [Bromoxynil <SEP> of <SEP> species <SEP> of weeds
<tb> g (ep) / ha] <SEP> Ip <SEP> At <SEP> Ar <SEP> Ca <SEP> Together
<tb> (all <SEP> species)
<tb> Q <SEP> 85 <SEP> 40 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 10
<tb> 170 <SEP> 100 <SEP> 0 <SEP> 20 <SEP> 40 <SEP> 40
<tb> (ammonium salt <SEP>
<tb> 340 <SEP> 100 <SEP> 30 <SEP> 56 <SEP> 90 <SEP> 69
<tb> of <SEP> bromoxynil)
<tb> 680 <SEP> 100 <SEP> 70 <SEP> 90 <SEP> 100 <SEP> 90
<tb> 1360 <SEP> 100 <SEP> 98 <SEP> 100 <SEP> 100 <SEP> 99
<tb> R <SEP> 85 <SEP> 100 <SEP> 53 <SEP> 40 <SEP> 60 <SEP> 63
<tb> 170 <SEP> 100 <SEP> 80 <SEP> 95 <SEP> 90 <SEP> 91
<tb> (Octanoate <SEP> of
<tb> 340 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> bromoxynil)
<tb> 680 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> 1360 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100 <SEP> 100
<tb> TABLE 5

Formulation <SEP> Crop <SEP> Surface <SEP> foliar <SEP> necrotic
<tb> plant <SEP> Dose <SEP> [Bromoxynil <SEP> g (ep) / ha]
<tb> 85 <SEP> 170 <SEP> 340 <SEP> 680 <SEP> 1360
<tb> H <SEP> (Salt <SEP> of <SEP> trimethyl- <SEP> Corn <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 5
<tb> amine <SEP> of <SEP> bromoxynil) <SEP> Sorghum <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 5
<tb> I <SEP> (Salt <SEP> of <SEP> trimethyl- <SEP> Corn <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 5
<tb> amine <SEP> of <SEP> bromoxynil) <SEP> Sorghum <SEP> 0 <SEP> 0 <SEP> 0 <SEP><5<SEP> 10
<tb> J <SEP> (Salt <SEP> of <SEP> triethyl- <SEP> Corn <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0
<tb> amine <SEP> of <SEP> bromoxynil) <SEP> Sorghum <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 5
<tb> K <SEP> (Salt <SEP> of <SEP> triethyl- <SEP> Corn <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 5
<tb> amine <SEP> of <SEP> bromoxynil) <SEP> Sorghum <SEP> 0 <SEP> 0 <SEP> 0 <SEP><5<SEP> 10
<tb> L <SEP> (Salt <SEP> of <SEP> triethanol- <SEP> Corn <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 5 <SEP> 10
<tb> amine <SEP> of <SEP> bromoxynil) <SEP> Sorghum <SEP> 0 <SEP> 0 <SEP><5<SEP> 5 <SEP> 15
<tb> M <SEP> (Sel <SEP> of <SEP> tri-n-propyl- <SEP> Corn <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 5 <SEP> 15
<tb> amind <SEP> of <SEP> bromoxynil) <SEP> Sorghum <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 5 <SEP> 25
<tb> TABLE 5 (Continued)

Formulation <SEP> Surface <SEP> foliar <SEP> necrotic
<tb> Culture <SEP> Dose <SEP> [Bromoxynil <SEP> g (e <SEP> .p) / ha]
<tb> 85 <SEP> 170 <SEP> 340 <SEP> 680 <SEP> 1360
<tb> N <SEP> (Sel <SEP> of <SEP> tri-n-butyl- <SEP> Corn <SEP> 0 <SEP> 0 <SEP><5<SEP> 10 <SEP> 20
<tb> amine <SEP> of <SEP> bromoxynil <SEP> Sorghum <SEP> 0 <SEP> 0 <SEP><5<SEP> 5 <SEP> 23
<tb> O <SEP> (Salt <SEP> of <SEP> methyl-di-n- <SEP> Corn <SEP> 0 <SEP> 0 <SEP> 5 <SEP> 17 <SEP> 30
<tb> octylamine <SEP> of <SEP> bromoxynil <SEP> Sorghum <SEP> 0 <SEP><5<SEP> 5 <SEP> 20 <SEP> 35
<tb> P <SEP> (Salt <SEP> of <SEP> potassium <SEP> Corn <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0
<tb> of <SEP> bromoxynil) <SEP> Sorghum <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 5
<tb> Q <SEP> (Ammonium Salt <SEP> Corn <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0
<tb> of <SEP> bromoxynil) <SEP> Sorghum <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0 <SEP> 0
<tb> R <SEP> (Octanoate <SEP> of <SEP> Corn <SEP> 0 <SEP> 0 <SEP> 8 <SEP> 19 <SEP> 40
<tb> bromoxynil) <SEP> Sorghum <SEP> 0 <SEP> 0 <SEP> 10 <SEP> 21 <SEP> 44
<tb>("<" means "inferior to") TABLE 6

Formulation
<tb> Dose <SEP> causing <SEP><SEP><SEP> Dose <SEP><SEP> causing <SEP> not
<tb> truction <SEP> of <SEP> 95 <SEP>% <SEP> of <SEP> The <SEP> Plus <SEP> of <SEP> 5 <SEP>% <SEP> of <SEP> phytotose <SEP> of <SEP> weeds
<tb> [Bromoxynil <SEP> xicity <SEP> (foliar necrosis <SEP>) <SEP><SEP> Index <SEP> selectivity
<tb> g <SEP> (ep) / ha] <SEP> on <SEP> the <SEP> cultures
<tb> [Bromoxynil <SEP> g (ep) / ha]
<tb> Corn <SEP> Sorghum <SEP> Corn <SEP> Sorghum
<tb> H
<tb> (SEP <SEP> Sel <SEP> 340 <SEP> 1360 <SEP> 1360 <SEP> 4.0 <SEP> 4.0
<tb> methylamine
<tb> of <SEP> bromoxynil)
<tb> I
<tb> (Sel <SEP> of <SEP> tri- <SEP> 290 <SEP> 1360 <SEP> 1200 <SEP> 4.7 <SEP> 4.1
<tb> methylamine
<tb> of <SEP> bromoxynil)
<tb> J
<tb> (Salt <SEP> of <SEP> tri- <SEP> 320 <SEP>> 1360 <SE> 1360 <SE>> 4.3 <SEP> 4.3
<tb> ethylamine
<tb> of <SEP> bromoxynil)
<tb> K
<tb> (Sel <SEP> of <SEP> tri- <SEP> 270 <SEP> 1360 <SEP> 1200 <SEP> 5.0 <SEP> 4.4
<tb> ethylamine
<tb> of <SEP> bromoxynil)
<tb> TABLE 6 (Continued)

Formulation
<tb> Dose <SEP> causing <SEP><SEP><SEP> Dose <SEP><SEP> causing <SEP> not
<tb> truction <SEP> of <SEP> 95 <SEP>% <SEP> of <SEP> The <SEP> Plus <SEP> of <SEP> 5 <SEP>% <SEP> of <SEP> phytotose <SEP> of <SEP> weeds
<tb> xicity <SEP> (foliar necrosis <SEP>) <SEP><SEP> index of <SEP> selectivity
<tb> [Bromoxynil
<tb> on <SEP> the <SEP> culture
<tb> g <SEP> (ep) / ha]
<tb> [Bromoxynil <SEP> g (ep) / ha]
<tb> Corn <SEP> Sorghum <SEP> Corn <SEP> Sorghum
<tb> L
<tb> (Sel <SEP> of <SEP> trietha- <SEP> 450 <SEP> 680 <SEP> 680 <SEP> 1.5 <SEP> 1.5
<tb> nolamine <SEP> from
<tb> Bromoxynil)
<tb> M
<tb> (Sel <SEP> of <SEP> tri-n- <SEP> 520 <SEP> 680 <SEP> 680 <SEP> 1.3 <SEP> 1.3
<tb> propylamine
<tb> of <SEP> bromoxynil)
<tb> N
<tb> (Sel <SEP> of <SEP> tri-n- <SEP> 400 <SEP> 560 <SEP> 680 <SEP> 1.4 <SEP> 1.7
<tb> butylamine
<tb> of <SEP> bromoxynil)
<tb> O
<tb> (Salt <SEP> of <SEP> methyl- <SEP> 600 <SEP> 340 <SEP> 340 <SEP><1<SEP><1
<tb> di-n-octylamine
<tb> of <SEP> bromoxynil
<tb> TABLE 6 (Continued)

Formulation
<tb> Dose <SEP> causing <SEP> the <SEP> of
Dose <SEP> not <SEP> causing <SEP> not
<tb> truction <SEP> of <SEP> 95 <SEP>% <SEP> of <SEP> the more <SEP> of <SEP> 5 <SEP>% <SEP> of <SEP> phytotoxicity <SEP> of <SEP> weeds
<tb> cited <SEP> (foliar necrosis <SEP>) <SEP><SEP> Index <SEP> selectivity
<tb> [Bromoxynil
<tb> g <SEP> (ep) / ha] <SEP> on <SEP> the <SEP> culture
<tb> [Bromoxynil <SEP> g (ep) / ha]
<tb> Corn <SEP> Sorghum <SEP> Corn <SEP> Sorghum
<tb> P
<tb> (Salt <SEP> of <SEP> Potassium <SEP> 1100 <SEP>> 1360 <SEQ> 1360 <SEP>> 1.2 <SEP> 1.2
<tb> of <SEP> bromoxynil)
<tb> O
<tb> (Ammonium <SEP> Salt <SEP> 800 <SEP>> 1360 <SEP> 1360 <SEP>> 1.7 <SEP> 1.7
<tb> of <SEP> bromoxynil)
<tb> R
<tb> (Octanoate <SEP> of the <SEP> 200 <SEP> 300 <SEP> 280 <SEP> 1.5 <SEP> 1.4
<tb> bromoxynil)
<tb>(">" means "greater than";"<" means "less than")

Claims (9)

1) A method for selective anti-dicotyledonous weed control, post-emergence, of maize and sorghum crops, characterized in that the effective ingredient used is an effective herbicidal amount of the trimethylamine salt of dibromo-3,5-hydroxy-4- benzonitrile or triethylamine salt of dibromo-3,5-hydroxy-4-benzonitrile. 2) Process according to claim 1), characterized in that  that the active ingredient is applied at a dose of 100 to  1000 g and, preferably, from 150 to 600 g per hectare of bromoxyn 1. 3) Method according to one of claims 1 and 2)  characterized in that the active ingredient is associated with  at least one other herbicide and / or  applicable in levies and / or which is well tolerated by the  culture. 4) Method according to claim 3) characterized in that  the other herbicide is selected from the group consisting of  atrazine, simazine, cyanazine, propazine,  terbutylazine, linuron, isoproturon, aciAtate  dinoseb, dinoseb amine, dinoterb, dicambaset  MCPA and their metal or amine salts or their esters. 5) Method according to one of the claims characterized in that  that he is following a pre-emergence treatment of the culture with  alachlor, metolachlor, pendimethalin,  butylate, vernolate, EPTC or a 12/1 blend of EPTC  and N, N-diallyl 2,2-dichloroacetamide. 6) As a new compound, the triethylamine salt of  3,5-dibromo-4-hydroxy-benzonitrile. 7) Process for preparing the compound according to the claim  6) characterized in that quantities are reacted  stoichiometric levels of bromoxynil and triethylamine in  an inert solvent. 8) Process according to claim 7, characterized in that  the inert solvent can be used in formulation  herbicide. 9) A herbicidal composition characterized in that  contains as active ingredient the triethylamine salt of the  3,5-dibromo-4-hydroxy-benzonitrile.  10) Herbicidal composition characterized in that it con  also maintains a pre-emergence herbicide.