WO2024062498A1

WO2024062498A1 - Synergistic ternary herbicidal composition

Info

Publication number: WO2024062498A1
Application number: PCT/IN2023/050875
Authority: WO
Inventors: Parikshit MUNDHRA; Jitendra Mohan
Original assignee: Willowood Chemicals Limited
Priority date: 2022-09-21
Filing date: 2023-09-21
Publication date: 2024-03-28

Abstract

The present invention provides synergistic ternary herbicidal compositions comprising Metribuzin and at least one herbicidal compound selected from Halosulfuron-methyl or Fenoxaprop-p-ethyl and at least one herbicidal compound selected from Ametryn or Bentazone/Bentazone sodium, formulation thereof and to a method of controlling undesired vegetation in crops of useful plants.

Description

FIELD OF THE INVENTION

The present invention relates to synergistic ternary herbicidal compositions comprising Metribuzin and at least one herbicidal compound selected from Halosulfuron-methyl or Fenoxaprop-p-ethyl and at least one herbicidal compound selected from Ametryn or Bentazone/Bentazone sodium, formulation thereof and to a method of controlling undesired vegetation in crops of useful plants.

BACKGROUND OF THE INVENTION

Weeds and other unwanted vegetation inhibiting crop growth is a constantly recurring problem in agriculture. Therefore, the control of weeds or unwanted plants is economically important for the crop productivity. Researchers in the field of synthetic chemistry have produced an extensive variety of chemicals and chemical formulations as solo or in combination of active ingredients for the control of such weeds or unwanted plants. Formulation of chemical herbicides of many types have been disclosed in the literature and a large number of them are in commercial use.

Now a days in order to reduce the risk from increased number of herbicide resistant varieties of weeds, mixtures of different active compounds are employed for controlling weeds or unwanted plants. By combining different active compounds having different mechanism of action, it is possible to ensure successful control of large no. of weeds over a relatively longer period of time and preventing development of resistance. However, this requires continuous development of an effective composition with different active compounds, so as to avoid selection to the particular mechanism of action.

Therefore, there exists a continuous need to develop an herbicidal composition which is compatible and stable, synergistic, broad spectrum, environmentally safe and more effective in control of weeds or undesired plants in crops while using low content of actives. It is highly desirable that herbicidal compositions must show a broader scope of activity to avoid or to control the development of resistant varieties of weeds to the active ingredient (s) or to the mixtures of known active ingredients used by farmer while minimising the doses of chemical products sprayed in the agricultural fields. As a solution to the above mentioned problems, the inventors of the present invention surprisingly found that composition comprising Metribuzin and at least one herbicidal compound selected from Halosulfuron-methyl or Fenoxaprop-p-ethyl and at least one herbicidal compound selected from Ametryn or Bentazone/Bentazone sodium provides effective control of wide range of weeds or undesired plants with much lesser amounts of actives along with other associated advantages.

SUMMARY OF THE INVENTION

Accordingly, the present invention provides a combination comprising of Metribuzin and at least one herbicidal compound selected from Halosulfuron-methyl or Fenoxaprop-p-ethyl and at least one herbicidal compound selected from Ametryn or Bentazone/Bentazone sodium and agriculturally acceptable additives.

In one aspect, the composition of the present invention comprises Metribuzin in the range of 1-50 % w/w; compound selected from Halosulfuron-methyl in the range of 1-50 % w/w or Fenoxaprop-p-ethyl in the range of 1-50 % w/w; and compound selected from Ametryn in the range of 1-50 % w/w or Bentazone/Bentazone sodium in the range of 1-50 % w/w and agriculturally acceptable additives.

In one other aspect, the composition of the present invention comprises Metribuzin preferably in the range of 1 -50 % w/w; compound selected from Halosulfuron-methyl in the range of 0.5- 10% w/w or Fenoxaprop-p-ethyl in the range of 0.5-10 % w/w; and compound selected from Ametryn in the range of 5-50% w/w or Bentazone/Bentazone sodium in the range of 5-50% w/w and agriculturally acceptable additives.

In one another aspect, the composition of the present invention comprises Metribuzin more preferably in an amount of 3.4-24% w/w; compound selected from Halosulfuron-methyl in an amount of 1.4-2.6% w/w or Fenoxaprop-p-ethyl in an amount of 2.0-2.9%; and compound selected from Ametryn in an amount of 13-24 % w/w or Bentazone/Bentazone sodium in an amount of 11.2-24.3% w/w and agriculturally acceptable additives.

In an aspect, the composition of the present invention is formulated as Capsule suspension (CS), Dispersible concentrate (DC), Dustable powder (DP), Emulsifiable granule (EG), Emulsion water-in-oil (EO), Emulsifiable powder (EP), Granules (GR), Oil-dispersion (OD), Oil miscible flowable concentrate (OF), Oil miscible liquid (OL), Oil dispersible powder (OP), Suspension concentrate (SC), Suspension concentrate for direct application (SD), Suspo- emulsion (SE), Water soluble granule (SG), Soluble concentrate (SL), Spreading oil (SO), Water soluble powder (SP), Water soluble tablet (ST), Ultra-low volume (ULV) suspension, Tablet (TB), Ultra-low volume (ULV) liquid, Water dispersible granules (WG), Wettable powder (WP), Water dispersible tablet (WT), a mixed formulation of CS and SC (ZC) or A mixed formulation of CS and SE (ZE), preferably WP and SC.

In another aspect, the composition of the present invention comprises one or more agriculturally acceptable additive selected from the group comprising of dispersing agent(s), wetting agent(s), dispersing cum wetting agent(s), safener(s), defoaming agent(s) / defoamer(s) / antifoaming agent(s) / antifoamer(s), biocide(s)/preservative(s), viscosity modifier(s)/ rheology modifier(s)/ thickener (s), anti-settling agent(s), filler(s) and diluent(s) or a combination thereof and other additives as will be required in a particular type of formulation.

In another aspect, the composition of the present invention comprises the dispersing agent is selected from the group comprising naphthalene sulfonate formaldehyde condensate, sulfonated kraft lignin polymer, polymethyl methacrylate -polyethylene oxide graft copolymer, amine salt of phosphate tristyryl phenol ethoxylated, acrylic copolymer, graft copolymer, salt of naphthalene sulphonate, phosphate ester, salt of polycarboxylate, alcohol block copolymer, ethoxylated polyarylphenol phosphate ester, tristyrylphenol ethoxylate phosphate ester, or a combination thereof and present in an amount in the range from 0.1-5% w/w; the wetting agent is selected from the group comprising sodium isopropyl naphthalene sulfonate, sodium dioctyl sulphosuccinate, a copolymer condensate of ethylene and propylene oxide, sodium alkyl naphthalene sulfonate blend, ethoxylated polyarylphenol phosphate ester, non-ionic ethoxylate, castor oil ethoxylate or a combination thereof and present in an amount in the range from 0.1-5% w/w; the dispersing cum wetting agent is selected from the group comprising proprietary blend of phosphate ester and sodium naphthalene sulfonate formaldehyde condensate, highly sulfonation and low molecular weight kraft lignin polymer, sodium salt of aromatic ring surfactant, ammonium salt of aromatic ring surfactant, sodium salt of naphthalene sulphonic acid condensation, proprietary blend of anionic surfactant, sodium methyl oleoyl taurate, tristyrylphenol ethoxylate phosphate ester or a combination thereof and present in an amount in the range from 2-7% w/w; the safener is mefenpyr-diethyl and present in an amount in the range from 0.01 to 2% w/w; the defoamer is polydimethylsiloxane antifoam emulsion and present in an amount in the range from 0.01 to 1% w/w; the biocide/preservative is selected from the group comprising 20% aqueous dipropylene glycol solution of 1, 2- benzisothiazolin-3-one, formaldehyde, isothiazolinone or a combination thereof and present in an amount in the range from 0.01 to 1% w/w; the viscosity modifier is selected from the group comprising xanthan gum (2% solution), guar gum and present in an amount in the range from 5-15% w/w; the anti-settling agent is selected from the group comprising precipitated silica, organic bentonite, polyolefin particles and fumed silica and present in an amount in the range from 1.5 to 3.5% w/w; the filler is selected from the group comprising silica, sodium bicarbonate, china clay, lactose, bentonite clay, kaolin, diatomaceous earth or a combination thereof and present in an amount quantity sufficient; the diluent is demineralised water and present in an amount quantity sufficient.

DETAILED DESCRIPTION OF THE INVENTION

The definitions provided herein for the terminologies used in the present disclosure are for illustrative purpose only and in no manner limit the scope of the present invention disclosed in the present disclosure.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by a person of ordinary skill in the art to which the invention pertains. Although other methods and materials similar, or equivalent, to those described herein can be used in the practice of the present invention, the preferred materials and methods are described herein.

It is to be noted that, as used in the specification and the appended claims, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a composition containing “a compound” includes a mixture of two or more compounds. It should also be noted that the term “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise.

As used herein, the terms "comprises", "comprising", "includes", "including", “has”, “having”, “contains”, “containing”, “characterized by” or any other variation thereof, are intended to cover a non-exclusive inclusion, subject to any limitation explicitly indicated. For example, a composition, mixture, process or a method that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, mixture, process or method.

The transitional phrase “consisting of’ excludes any element, step or ingredient not specified. If in the claim, such would close the claim to the inclusion of materials other than those recited except for impurities ordinarily associated therewith. When the phrase “consisting of’ appears in a clause of the body of a claim, rather than immediately following the preamble, it limits only the element set forth in that clause; other elements are not excluded from the claim as a whole.

As used herein, the terms “composition” or "formulation" can be used interchangeably, unless stated otherwise, is meant to encompass, and are not limited to, compositions or formulations containing the combination of Metribuzin and at least one herbicidal compound selected from Halosulfuron-methyl or Fenoxaprop-p-ethyl and at least one herbicidal compound selected from Ametryn or Bentazone/Bentazone sodium.

As used herein, the term “agriculturally acceptable additive (s)” refers to inert substances and are auxiliary substances added to the processing or use of herbicide preparations and used to improve the physical and chemical properties of formulations. The auxiliaries themselves are essentially free of biological activity, but can affect the control effect.

The expression of various quantities in terms of “% w/w” or “%” means the percentage by weight, relative to the weight of the total solute on or composition unless otherwise specified.

The term “active ingredient” (a.i.) or “active agent” used herein refers to that component of the composition responsible for control of weeds or undesired plants.

As used herein, the term "effective amount" means the amount of the active substances in the compositions to achieve an observable effect on growth, including the effects of necrosis, death, retardation, prevention, and removal, destruction, or otherwise diminishing the occurrence and activity of the target weeds. An effective amount of the compositions will also vary according to the prevailing conditions such as desired herbicidal effect and duration, weather, target species, locus, mode of application, and the like.

As used herein, the term “herbicide”, refers to any chemical substance used to destroy/kill, delay, reduce, inhibit or otherwise adversely affect the growth of plants, especially weeds. As used herein, the term “Metribuzin” encompasses its agrochemically acceptable salt(s), derivative(s) or any other modified form of Metribuzin. Metribuzin having IUPAC name 4- amino-6-tert-butyl-3- methylsulfanyl- 1, 2, 4-triazin-5-one belongs to the group of triazinone herbicide. It acts by inhibition of photosystem II. It is a selective systemic herbicide, absorbed predominantly by the roots, but also by the leaves, with acropetal translocation in the xylem. It is used for pre and post-emergence control of grass and broad-leaved weeds in soybeans, potatoes, tomatoes, sugarcane, alfalfa, asparagus, maize and cereals.

As used herein, the term “Halosulfuron-methyl” is a derivative of Halosulfuron and encompasses its agrochemically acceptable salt(s), derivative(s) or any other modified form of Halosulfuron-methyl. Halosulfuron-methyl having IUPAC name methyl 3-chloro-5-(4, 6- dimethoxypyrimidin-2-ylcarbamoylsulfamoyl)-l-methylpyrazole-4-carboxylate belongs to pyrazole herbicide or pyrimidinylsulfonylurea herbicide. It shows its action by inhibiting acetolactate synthase (ALS) enzyme.

As used herein, the term “Fenoxaprop-p-ethyl” encompasses its agrochemically acceptable salt(s), acids such as Fenoxaprop, Fenoxaprop-p-ethyl, derivative(s) or any other modified form of Fenoxaprop-p-ethyl. Fenoxaprop-p-ethyl having IUPAC name (R)-2-[4-(6-chloro-l,3- benzoxazol-2-yloxy) phenoxy] propionic acid belongs to the class of aryloxyphenoxy propionate. It acts by acetyl CoA carboxylase inhibition. It is a selective herbicide with contact and systemic action, absorbed principally by the leaves, with translocation both acropetally and basipetally to the roots or rhizomes. It is used for post-emergence control of annual and perennial grass weeds in potatoes, beans, soybeans, beets, vegetables, peanuts, flax, oilseed rape and cotton.

As used herein, the term “Ametryn” encompasses its agrochemically acceptable salt(s), derivative(s) or any other modified form of Ametryn. Ametryn having IUPAC name N²-ethyl- N⁴-isopropyl-6-(methylthio)-l, 3, 5-triazine-2,4-diamine belongs to the group of triazine herbicide. It acts by binds to the plastoquinone-binding protein in photosystem II, inhibiting electron transport. Ametryn is a thiotriazine selective systematic herbicide absorbed principally through the roots, but also through the foliage, translocated acropetally in the xylem and accumulated in the apical meristems and leaves. It is used in banana, citrus, palm, and coffee and has limited use as a post directed spray on com. Ametryn is effective against annual broadleaf weeds and grasses and is often used in tank mixes and in prepacks with other products. Ametryn is used for pre-emergence and post-emergence control of both monocotyledonous and dicotyledonous weeds in corn, sugarcane, banana, pineapple, and noncrop areas.

As used herein, the term “Bentazone” encompasses its agrochemically acceptable salt(s) preferably “Bentazone sodium”, derivative(s) or any other modified form of Bentazone. Bentazone having IUPAC name 3-isopropyl-lH-2, 1, 3-benzothiadiazin-4(3H)-one 2,2- dioxide belongs to the group of benzothiadiazinone herbicide. It acts by inhibition of photosystem II. It is a selective contact herbicide. It is used for post-emergence control of broad-leaved weeds in winter and spring cereals, peanuts, maize, peas, Phaseolus beans, rice and soybeans.

In an embodiment, the present invention provides a synergistic ternary herbicidal composition comprising of Metribuzin and at least one herbicidal compound selected from Halosulfuron- methyl or Fenoxaprop-p-ethyl and at least one herbicidal compound selected from Ametryn or Bentazone/Bentazone sodium and agriculturally acceptable additives.

In an embodiment, the present invention provides a synergistic ternary herbicidal compositions of Metribuzin in the range of 1-50 % w/w; compound selected from Halosulfuron-methyl in the range of 1-50 % w/w or Fenoxaprop-p-ethyl in the range of 1-50 % w/w; and compound selected from Ametryn in the range of 1-50 % w/w or Bentazone/Bentazone sodium in the range of 1-50 % w/w and agriculturally acceptable additives.

In an embodiment, the present invention provides a synergistic ternary herbicidal compositions of Metribuzin preferably in the range of 1-50 % w/w; compound selected from Halosulfuron- methyl in the range of 0.5-10% w/w or Fenoxaprop-p-ethyl in the range of 0.5-10 % w/w; and compound selected from Ametryn in the range of 5-50% w/w or Bentazone/Bentazone sodium in the range of 5-50% w/w and agriculturally acceptable additives.

In other embodiment, the present invention provides a synergistic ternary herbicidal compositions of Metribuzin is more preferably present in an amount of 3.4-24% w/w; compound selected from Halosulfuron-methyl is more preferably present in an amount of 1.4- 2.6% w/w or Fenoxaprop-p-ethyl is more preferably present in an amount of 2.0-2.9%; and compound selected from Ametryn is more preferably present in an amount of 13-24 % w/w or Bentazone/ Bentazone sodium is more preferably present in an amount of 11.2-24.3% w/w and agriculturally acceptable additives. In an aspect, the composition of the present invention is formulated as Capsule suspension (CS), Dispersible concentrate (DC), Dustable powder (DP), Emulsifiable granule (EG), Emulsion water-in-oil (EO), Emulsifiable powder (EP), Granules (GR), Oil-dispersion (OD), Oil miscible flowable concentrate (OF), Oil miscible liquid (OL), Oil dispersible powder (OP), Suspension concentrate (SC), Suspension concentrate for direct application (SD), Suspo- emulsion (SE), Water soluble granule (SG), Soluble concentrate (SL), Spreading oil (SO), Water soluble powder (SP), Water soluble tablet (ST), Ultra-low volume (ULV) suspension, Tablet (TB), Ultra-low volume (ULV) liquid, Water dispersible granules (WG), Wettable powder (WP), Water dispersible tablet (WT), a mixed formulation of CS and SC (ZC) or A mixed formulation of CS and SE (ZE), preferably WP and SC.

In an embodiment, the composition of the present invention comprises one or more agriculturally acceptable additive selected from the group comprising of dispersing agent(s), wetting agent(s), dispersing cum wetting agent(s), safener(s), defoaming agent(s) / defoamer(s) / antifoaming agent(s) / antifoamer(s), biocide(s)/preservative(s), viscosity modifier(s)/ rheology modifier(s)/ thickener (s), anti-settling agent(s), filler(s) and diluent(s) or a combination thereof and other additives as will be required in a particular type of formulation.

The composition of present invention uses dispersing agents to prevent agglomeration of solid particles and keep them suspended in fluid. Non-limiting examples of dispersing agent that can be used in the present invention include, but not limited to naphthalene sulfonate formaldehyde condensate, sulfonated kraft lignin polymer, polymethyl methacrylate -polyethylene oxide graft copolymer, amine salt of phosphate tristyryl phenol ethoxylated, acrylic copolymer, graft copolymer, salt of naphthalene sulphonate, phosphate ester, salt of polycarboxylate, alcohol block copolymer, ethoxylated polyarylphenol phosphate ester, tristyrylphenol ethoxylate phosphate ester. One or more dispersing agents may be used in the synergistic composition of the present invention. The dispersing agent is present in the range from 1 to 10 % w/w, preferably 0.1-5% w/w.

The composition of present invention uses wetting agent to facilitate the process of dispersion of the granules in the liquid. Non-limiting examples of wetting agents that can be used in the present invention include, but not limited to, sodium isopropyl naphthalene sulfonate, sodium dioctyl sulphosuccinate, a copolymer condensate of ethylene and propylene oxide, sodium alkyl naphthalene sulfonate blend, ethoxylated polyarylphenol phosphate ester, non-ionic ethoxylate, castor oil ethoxylated. One or more wetting agents may be used in the synergistic composition of the present invention. The wetting agents is present in the range from 0.1-10% w/w, preferably 0.1-5% w/w.

The composition of present invention also uses dispersing cum wetting agent. Non-limiting examples of dispersing cum wetting agent that can be used in the present invention include, but not limited to, proprietary blend of phosphate ester and sodium naphthalene sulfonate formaldehyde condensate, highly sulfonation and low molecular weight kraft lignin polymer, sodium salt of aromatic ring surfactant, ammonium salt of aromatic ring surfactant, sodium salt of naphthalene sulphonic acid condensation, proprietary blend of anionic surfactant, sodium methyl oleoyl taurate, tristyrylphenol ethoxylate phosphate ester. One or more dispersing cum wetting agent may be used in the synergistic composition of the present invention. Dispersing cum wetting agent is present in the range from 1-10% w/w, preferably 2-7 % w/w. Use of dispersing cum wetting agent not only reduce a total cost of formulation but also lower a chemical burden on environment.

A safener is to be understood as meaning a compound which eliminates or reduces the phytotoxic properties of herbicide in respect to useful plants, without substantially reducing the herbicidal activity against harmful plants. Non limiting examples of safeners that can be employed in present invention are mefenpyr, mefenpyr-diethyl, AD67, benoxacor, cloquintocet-mexyl, cyometrinil, cyprosulfamide, dichlormid, dicyclonon, dietholate, fenchlorazole, fenchlorazole-ethyl, fenclorim, flurazole, fluxofenim, furilazole, isoxadifen- ethyl, mephenate, metcamifen, naphthalic anhydride, oroxabetrinil, 4-(dichloroacetyl)-l-oxa- 4- azaspiro[4.5]decane and 2,2,5-trimethyl-3- (dichloroacetyl)- 1,3-oxazolidine or a combination thereof and is present in the range from 0.01 to 5% w/w, preferably 0.01-2 % w/w.

The composition of present invention uses defoaming agent. Suitable defoamer used herein, but not limited to, polydimethylsiloxane antifoam emulsion, silicon emulsion, polysiloxane emulsion, organic fluorine compounds or a combination thereof and present in the range from 0.01 to 5% w/w, preferably 0.01-1% w/w.

The composition of present invention uses biocide/preservatives to prevent the composition from spoilage due to bacteria, yeasts and fungi. Suitable biocide/preservative used herein, but not limited to 20% aqueous dipropylene glycol solution of 1,2- benzisothiazolin-3-one, formaldehyde, potassium sorbate, 4-hydroxybenzoic acid esters, 2-methyl-4-isothiazolin-3- one, 5-chloro-2-methyl-4-isothiazolin-3-one or a combination thereof and present in the range from 0.01 to 5% w/w, preferably 0.01-1% w/w.

The composition of present invention uses viscosity modifier. Suitable viscosity modifier used herein, but not limited water-soluble polymer and inorganic fine powder, wherein water- soluble polymer selected from xanthan gum, polyvinyl alcohol, carboxymethylcellulose, polyvinylpyrrolidone, carboxyvinyl polymer, acrylic polymer, starch derivative or polysaccharide; or an inorganic fine powder selected from high purity silica, bentonite, white carbon or a combination thereof and present in the range from 1-20 % w/w, preferably 5-15% w/w.

The composition of present invention uses anti-settling agent. Suitable anti-settling agent is selected from the group comprising precipitated silica, organic bentonite, polyolefin particles and fumed silica and present in the range from 1 to 5% w/w, preferably 1.5-3.5% w/w.

The composition of present invention uses filler. Suitable fillers that may be used in the composition of the present invention include, but not limited to, silica, sodium bicarbonate, china clay, lactose, bentonite clay, kaolin, diatomaceous earth. The filler may be used in an amount of quantity sufficient to make 100%w/w formulation.

The composition of present invention uses diluents. Suitable diluents that may be used in the composition of the present invention is demineralised water and present in an amount quantity sufficient.

The inventors have surprisingly found that the composition of the present invention showed enhances control over existing compositions.

In another embodiment, the compositions of the present invention are effective in the management of pre-emergent or post-emergent, monocotyledonous and dicotyledonous weeds especially grasses such as Phalaris minor, Avena fatua, Cynadon dactylon, Poa annua, Setaria gluca, Digitaria sanguinalis, Brachiaria spp., Echinocloa spp., Dactyloctenium aegyptium; broad leaved weeds such as Chenopodium album, Cercium arvensis, Melilotus alba/indica, Argemone Mexicana, Fumaria parviflora, Asphodelus tenuifolius, Carthamus oxyacantha, Launea sp., Pluchia lanceolat, Vicia enticulus, Phyllanthus niruri., Lathyrus aphaca, Medicago enticulate, Medicago lupulina, Spergula arvensis, Ipomea spp., Ageratum conyzoides, Tribulus terrestris, Anagalis arvensis, Alternenthera sessalis, Trianthama monogyna, Trianthama portulacastum, Boerhaavia diffusa, Portulaca oleracea, Commelina benghalensis, Parthenium hysterophorus, Euphorbia hirta, Setaria veridis, Amaranthus viridis, Rumex denticulata Convolvulus arvensis, Trianthema monogyna, Euphorbia geniculate, Amaranthus spinosus, Cloeme gynandra, Coccinia indica; sedges such as Cyperus rotundus, Cyperus Iria and Cyperus difformis.

The present invention also provides a process of preparing a composition comprising of Metribuzin and at least one herbicidal compound selected from Halosulfuron-methyl or Fenoxaprop-p-ethyl and at least one herbicidal compound selected from Ametryn or Bentazone/Bentazone sodium and at least one agriculturally acceptable additive.

In an embodiment, the present invention provides a process for the preparation of a WP formulation which comprises: a) weighing and mixing of required active ingredients and other ingredients; b) milling in a suitable air jet mill; c) grinding the material to obtain desired particle size (D90- <10 micron) and d) mixing homogeneously in a blender to obtain the wettable powder formulation.

In another embodiment, the present invention provides a process for the preparation of a SC formulation which comprises: a) diluting and solubilizing a biocide, defoamer, antifreeze agent and anti-settling agent in demineralised water in a mixing vessel and adding dispersing and wetting agent under stirring to get homogeneous mixture; b) adding active ingredients and safener one by one under stirring and mixing till homogeneous slurry obtained; c)wet grinding at suitable temperature till desired particle size obtained, if required water washing done and d) adding previously prepared viscosity modifier solution and stirring to obtain homogeneous mixture.

The composition of the present invention can be applied by spraying using flat-fan or flood-jet nozzles.

The rate of application amount of the prepared compositions varies depending on, for example, the blending ratio of active ingredients, meteorological condition, dosage form, application time, application method, application place, weed to be controlled, and a target crop, in ordinary cases. In an embodiment of the present invention, combination of Metribuzin + Halosulfuron-methyl + Ametryn and Metribuzin + Halosulfuron-methyl + Bentazone/Bentazone sodium used for the pre-emergence or post-emergence weed control in variety of crops, including but not limited to sugarcane, wheat, potato, fibre crops, plantations and non-crop lands, preferably used in sugarcane, wheat and potato crops. As known to agro community sedges are a biggest problem in sugarcane field and needs to be controlled very effectively. At present Halosulfuron-methyl is widely used to control sedges in sugarcane fields, however its continuous use as a solo product not providing satisfactory results against sedges and further it provides no control on grasses and broad leaved weeds, the occurrence of grasses and broad leaved weeds cannot be overruled in sugarcane filed and in this case farmers have to use other herbicide which gives them cost burden whereas the combination of present invention Metribuzin+ Halosulfuron-methyl + Ametryn and Metribuzin + Halosulfuron-methyl + Bentazone/Bentazone sodium is not only very effective to control the sedges in sugarcane field but additionally it also provides excellent control against grasses and broad leaved weeds. Further due to synergistic nature of composition the much low amount of actives is used which benefitted to farmers as well as environment.

In another embodiment the composition of present invention i.e., Metribuzin + Fenoxaprop-p- Ethyl + Bentazone /Bentazone sodium used for the post-emergence weed control in wheat and potatoes. At present phalaris minor is the major problematic weed in wheat which is resistant to most of the herbicides including fenoxaprop, clodinafop, pinoxaden, sulfosulfuron, etc. secondly to control phalaris minor farmers are compelled to use much higher doses with multiple applications and cocktail of herbicides, even though effective control is not achieved and also suffers losses due to phytotoxicity. In this situation Metribuzin is the only favourably mixing partner to control resistant phalaris minor but results are still not satisfactory. Moreover occurrence of sedges specifically water scarce wheat field and broad leaved weeds cannot be overruled, hence the combination of present invention is effective not only for resistant phalaris minor but in a single shot use to control broad leaved weeds as well as sedges. Further due to synergistic nature of composition the much low amount of actives is used which benefitted to farmers as well as environment.

The synergistic composition of the present invention provides a number of other advantages:

• Increased efficacy in comparison to the other formulations tested during the trial. • Is synergistic hence denies the need of sequential application of solo herbicides to control different weed spectra thereby reducing the environmental load of herbicides.

• Uses lesser amounts of active ingredients hence considerable reduction in cost, which would benefit farmers.

• This composition provided one shot solution to farmers to control broad spectrum weeds (grasses, broad leaved weeds and sedges)

• Economically beneficial to the farmers as it provides better yield of the crop with reduction in the number of sprays.

• Reduced possibility of hazards to the farmers due to occupational exposure because of reduction in the number of sprays.

• Is storage stable.

• Is non-phytotoxic.

• Environmental friendly.

Thus, from the foregoing description, it will be apparent to one of the person skilled in the art that many changes and modifications can be made thereto without departing from the scope of the invention as set forth in the description. Accordingly, it is not intended that the scope of the foregoing description be limited to the description set forth above, but rather that such description be construed as encompassing such features that reside in the present invention, including all the features and embodiments that would be treated as equivalents thereof by those skilled in the relevant art.

The embodiments of the present invention are more particularly described in the following examples that are intended as illustrations only, since numerous modifications and variations within the scope of the present invention will be apparent to those of skill in the art. Unless otherwise noted, all parts, percentages and ratio reported in the following examples are on a weight basis and all excipients used in the examples were obtained or are available from the chemical suppliers.

EXAMPLES

The synergistic ternary herbicidal composition of the present invention comprising Metribuzin and at least one herbicidal compound selected from Halosulfuron-methyl or Fenoxaprop-p- ethyl and at least one herbicidal compound selected from Ametryn or Bentazone/Bentazone sodium and agriculturally acceptable additives in WP/SC form is provided in example 1 to 21. The unit of each component of the composition are expressed in “% w/w” i.e. the percentage by weight, relative to the weight of the total solution or composition. All the prepared composition of the present invention has been tested for stability/shelf life at accelerated temperature.

Table 1: Examples 1 to 5: Metribuzin + Halosulfuron-methyl + Ametryn (WP)

Tech=Technical Table 2: Quantities of active ingredients and raw material charged to prepare the composition of Metribuzin 10%+Halosulfuron-methyl 2%+ Ametryn 20% (WP)

Table 3: Stability studies (Shelf life based on accelerated storage at 54 ± 2°C)

Table 4: Examples 6 to 10: Metribuzin + Halosulfuron-methyl + Bentazone Sodium (WP)

Table 5: Quantities of active ingredients and raw material charged to prepare the composition of Metribuzin 24%+Halosulfuron-methyl 1.8%+ Bentazone sodium 11.2% (WP)

Table 6: Stability studies (Shelf life based on accelerated storage at 54 ± 2°C)

Table 7: Examples 11 to 15: Metribuzin + Halosulfuron-methyl + Bentazone (WP)

Table 8: Quantities of active ingredients and raw material charged to prepare the composition of Metribuzin 24%+Halosulfuron-methyl 1.8%+ Bentazone 11.2% (WP)

Table 9: Stability studies (Shelf life based on accelerated storage at 54 + 2°C)

Table 10: Examples 16 to 20: Metribuzin + Fenoxaprop-p-Ethyl + Bentazone sodium (WP)

Table 11: Quantities of active ingredients and raw material charged to prepare the composition of Metribuzin 6%+ Fenoxaprop-p-ethyl 2.9%+ Bentazone sodium 12.9% WP

Table 12: Stability studies (Shelf life based on accelerated storage at 54 + 2°C)

Table 13: Examples 21 to 25: Metribuzin + Fenoxaprop-p-Ethyl + Bentazone (WP)

Table 14: Quantities of active ingredients and raw material charged to prepare the composition of Metribuzin 6%+ Fenoxaprop-p-ethyl 2.9%+ Bentazone 12.9% WP

Table 15: Stability studies (Shelf life based on accelerated storage at 54 ± 2°C)

Table 16: Examples 26 to 30: Metribuzin + Fenoxaprop-p-Ethyl + Bentazone sodium (SC)

Table 17: Quantities of active ingredients and raw material charged to prepare the composition of Metribuzin 6%+ Fenoxaprop-p-ethyl 2.9%+ Bentazone sodium 12.9% SC

Table 18: Stability studies (Shelf life based on accelerated storage at 54 + 2°C)

Table 19: Examples 31 to 35: Metribuzin + Fenoxaprop-p-Ethyl + Bentazone (SC)

Table 20: Quantities of active ingredients and raw material charged to prepare the composition of Metribuzin 6%+ Fenoxaprop-p-ethyl 2.9%+ Bentazone 12.9% SC

Table 21: Stability studies (Shelf life based on accelerated storage at 54 ± 2°C)

As evident from the foregoing tables that all the desired composition has been prepared successfully and has been tested for stability/shelf life at accelerated temperature. After 14 days of storage at 54.0 ± 2 °C, there were no significant changes in active ingredient content, suspensibility, wettability, dispersibility, pH and has passes the sieve test. Therefore, it is concluded that composition of present invention has good stability and shelf life. Bio-efficacy of the herbicidal composition of the present invention

The abbreviations used in present application for variety of Grasses, Broad leaved Weeds (BLW/BL) and Sedges are defined below:

Experimental design and method for Sugarcane crop

Experimental trial was conducted to evaluate the herbicidal composition of the present invention in India against major weeds in sugarcane crop with ternary composition of present invention and comparative solo and binary compositions as per the details provided in Table 22-35.

The experiment was laid out in Randomized Block Design (RBD). The plot size was 10 m x 10 m and the spacing was 90 cm x 60 cm. All the recommended agronomic practices were followed throughout the cropping period. The different formulations were weighed according to the doses and diluted in water and applied using high volume knapsack sprayer fitted with a pressure regulator and a vertical bar with one flat fan nozzle and evaluated for % WCE (weed control efficiency) at 30 days after herbicide application (DAHA). 500 L/ha of water was used to dilute recommended doses of the formulation in the trial.

Observations from a composite sample (collected from three different spots in the experimental area) were recorded at 30 Days after herbicide application (DAHA). On the day of taking observation, weeds were collected from one square meter of each experimental plot and were cleaned. Weeds were then separated species wise and were oven dried and then weight was taken separately. Weed control efficacy for individual species was calculated using the formula:

W.C.E (%) = Weed population in control plot — weed population in treated plot X 100 Weed population in control plot

Experimental design and method for Wheat crop:

Two experimental trials to evaluate the herbicidal composition of the present invention were conducted at different trial sites in Ghaziabad (U.P.) and Kamal (Haryana), India against grassy, broad leaved weeds and sedges of wheat crop (variety DARA in Ghaziabad and HD 2968 in Kamal), which are prevalent in all wheat growing seasons with ternary composition of present invention and comparative solo and binary compositions as per the treatment details provided in Table 36-41. The experiment was laid out in Randomized Block Design (RBD). The plot size was 10m x 10m and the spacing was 20cm x 10cm. All the recommended agronomic practices were followed throughout the cropping period. The different formulations were weighed according to the doses and diluted in water and applied using high volume knapsack sprayer fitted with a pressure regulator and a vertical bar with one flat fan nozzle at 25 days after sowing (DAS) at all locations and evaluated for % WCE (weed control efficiency) at 21 days after herbicide application (DAHA). 500 L/ha of water was used to dilute the recommended dose of formulation in all trials.

Weeds were collected from one square meter of each experimental plot and were cleaned and separated species wise. Weeds in different species were oven dried and then weight was taken separately. Weed control efficiency for individual species was calculated using the formula as provided above.

Evaluation of synergistic effect

A synergistic effect exists whenever the action of an active ingredient combination is greater than the sum of the actions of the individual components. Synergism was calculated by using Colby’s method, Weeds, vol. 15 No. l(Jan 1967), pp. 20-2.

The synergistic action expected for a given combination of three active components can be calculated as follows:

(XY+YZ+XZ) XYZ E=(X+Y+Z) - - - - + -

100 10000

Where:

E represents expected percentage of control for the combination of the three active ingredients at defined doses (for example equal to x, y and z respectively),

X is the percentage of control observed by the compound (I) at a defined dose (equal to x),

Y is the percentage of control observed by the compound (II) at a defined dose (equal to y),

Z is the percentage of control observed by the compound (III) at a defined dose (equal to z).

If observed control of the combination > Expected control, the combination is synergistic (Colby ratio > 1)

If observed control of the combination < Expected control, the combination is antagonistic (Colby ratio < 1) If observed control of the combination = Expected control, the combination is additive (Colby ratio =1)

Evaluation of Sugarcane/Wheat Yield: Canes from each experimental plot were harvested and weight of canes was taken. Afterwards weight was converted to yield into ton per hectare (t/ha). Similarly, for wheat crop plants from each experimental plot were harvested and grains were separated and weight of grains was taken. Thereafter weight was converted to yield into kg per hectare. Efficacy of herbicide compositions of present invention was evaluated by calculating the % increase in yield of cane and wheat grain against control.

Phytotoxicity Observations: Synergistic ternary herbicidal compositions of the present invention were found to be non-phytotoxic on sugarcane and wheat crop.

Table 22: Treatment Details of Ternary herbicidal composition Metribuzin + Halosulfuron- methyl + Ametryn

Table 23: Effect of treatments on weed control efficiency against Grasses on Sugarcane crop

*For details Refer Table 22;O=Observed WCE (%);E=Expected WCE (%) Calculated using

Colby Formula;CR=Colby ratio

Table 24: Effect of treatments on weed control efficiency against Broad leaved Weeds on Sugarcane crop

*For details Refer Table 22

Table 25: Effect of treatments on weed control efficiency against Broad leaved Weeds on Sugarcane crop

*For details Refer Table 22

Table 26: Effect of treatments on weed control efficiency against Broad leaved Weeds on Sugarcane crop

*For details Refer Table 22 Table 27: Effect of treatments on weed control efficiency against Sedges on Sugarcane crop

*For details Refer Table 22 Table 28: Effect of treatments on Sugarcane yield at harvest

*For details Refer Table 22

Table 29: Treatment Details of Ternary herbicidal composition Metribuzin +Halosulfuron- methyl + Bentazone/Bentazone sodium

Table 30: Effect of treatments on weed control efficiency against Grasses on Sugarcane crop

*For details Refer Table 29 Table 31: Effect of treatments on weed control efficiency against Broad leaved Weeds on

Sugarcane crop

*For details Refer Table 29

Table 32: Effect of treatments on weed control efficiency against Broad leaved Weeds on Sugarcane crop

*For details Refer Table 29 Table 33: Effect of treatments on weed control efficiency against Broad leaved Weeds on Sugarcane crop

*For details Refer Table 29

Table 34: Effect of treatments on weed control efficiency against Sedges on Sugarcane crop

*For details Refer Table 29 Table 35: Effect of treatments on Cane yield at harvest

*For details Refer Table 29 Table 36: Treatment Details of Ternary herbicidal composition Metribuzin +Fenoxaprop-p-

Ethyl + Bentazone /Bentazone sodium

Table 37: Effect of treatments on weed control efficiency against Grasses on Wheat crop

*For details Refer Table 36 Table 38: Effect of treatments on weed control efficiency against Broad leaved Weeds on

Wheat crop

*For details Refer Table 36

Table 39: Effect of treatments on weed control efficiency against Broad leaved Weeds on Wheat crop

*For details Refer Table 36

Table 40: Effect of treatments on weed control efficiency against Sedges on Wheat crop

*For details Refer Table 36 Table 41: Effect of treatments on grain yield of wheat crop at harvest

*For details Refer Table 36 It is evident from the above tables 23-27, 30-34 and 37-40 that the ternary herbicidal composition of the present invention gave good control on tested weeds/undesired vegetation on sugarcane and wheat crops wherein all the prepared ternary composition found synergistic as compared to the reference products (solo or binary composition).

It has also been found that use of ternary composition of present invention not only gave better efficiency by using low a.i., content compared to binary and solo composition but also broaden the spectrum of composition as the binary compositions are not providing sufficient weed control in given duration.

It has also been found that the ternary composition of present invention provides a readymade solution to control the grasses, broad leaved weeds and sedges in one go. It has been observed that Metribuzin is effective to control mostly grasses and broad leaved weeds Halosulfuron- methyl is effective to control only for sedges and Ametryn is effective to control mostly grasses and broad leaved weeds whereas synergistic combination of present invention Metribuzin + Halosulfuron-methyl + Ametryn gives excellent control on all the tested weeds for duration of 30 days that too in single application. In the same line of results we noted that Bentazone /Bentazone sodium is effective on broad leaved weeds and sedges whereas fenoxaprop solo is effective on grasses but the synergistic combination of present invention Metribuzin + Fenoxaprop-p-Ethyl + Bentazone/Bentazone sodium is effective on grasses, broad leaved weeds and sedges for duration of 21 days that too in single application.

Further as evident from table 28, 35 and 41 that higher yield of cane and wheat grain is observed by using the ternary composition of present invention compared to binary composition. It is evident from table 28, 35 and 41 that % increase in cane yield and wheat grain yield against control is much higher.

From the foregoing it will be observed that numerous modifications and variations can be effectuated without departing from the true spirit and scope of the novel concepts of the present invention. It is to be understood that no limitations with respect to the specific embodiments illustrated is intended or should be inferred. It should be understood that all such modifications and improvements have been deleted herein for the sake of conciseness and readability but are properly within the scope of the following claims.

Claims

Claims:

1. A synergistic ternary herbicidal compositions comprising: a. Metribuzin; b. at least one compound selected from Halosulfuron-methyl or Fenoxaprop-p-ethyl; c. at least one compound selected from Ametryn or Bentazone/Bentazone sodium and d. agriculturally acceptable additives.

2. The synergistic ternary herbicidal compositions as claimed in claim 1, comprising: a. Metribuzin in the range of 3.4 to 24% w/w; b. at least one compound selected from Halosulfuron-methyl in the range of 1.4 to 2.6% w/w or Fenoxaprop-p-ethyl in the range of 2.0 to 2.9% w/w; c. at least one compound selected from Ametryn in the range of 13 to 24% w/w or Bentazone/Bentazone sodium in the range of 11.2 to 24.3% and d. agriculturally acceptable additives.

3. The synergistic ternary herbicidal compositions as claimed in claim 1, wherein the composition is formulated as Capsule suspension (CS), Dispersible concentrate (DC), Dustable powder (DP), Emulsifiable granule (EG), Emulsion water-in-oil (EO), Emulsifiable powder (EP), Granules (GR), Oil-dispersion (OD), Oil miscible flowable concentrate (OF), Oil miscible liquid (OL), Oil dispersible powder 5 (OP), Suspension concentrate (SC), Suspension concentrate for direct application (SD), Suspo-emulsion (SE), Water soluble granule (SG), Soluble concentrate (SL), Spreading oil (SO), Water soluble powder (SP), Water soluble tablet (ST), Ultra-low volume (ULV) suspension, Tablet (TB), Ultra-low volume (ULV) liquid, Water dispersible granules (WG), Wettable powder (WP), Water dispersible tablet (WT), a mixed formulation of CS and SC (ZC) or A mixed formulation of CS and SE (ZE), preferably WP and SC.

4. The synergistic ternary herbicidal compositions as claimed in claim 1, wherein the agriculturally acceptable additives is selected from the group comprising of dispersing agent, wetting agent, dispersing cum wetting agent, safener, defoamer, biocide/preservatives, viscosity modifier, anti-settling agent, filler and diluent.

5. The synergistic ternary herbicidal compositions as claimed in claim 4, wherein a. the dispersing agent is selected from the group comprising naphthalene sulfonate formaldehyde condensate, sulfonated kraft lignin polymer, polymethyl methacrylatepolyethylene oxide graft copolymer, amine salt of phosphate tristyryl phenol ethoxylated, acrylic copolymer, graft copolymer, salt of naphthalene sulphonate, phosphate ester, salt of polycarboxylate, alcohol block copolymer, ethoxylated polyarylphenol phosphate ester, tristyrylphenol ethoxylate phosphate ester, or a combination thereof and present in an amount in the range from 0.1-5% w/w; b. the wetting agent is selected from the group comprising sodium isopropyl naphthalene sulfonate, sodium dioctyl sulphosuccinate, a copolymer condensate of ethylene and propylene oxide, sodium alkyl naphthalene sulfonate blend, ethoxylated polyarylphenol phosphate ester, non-ionic ethoxylate, castor oil ethoxylate or a combination thereof and present in an amount in the range from 0.1-5% w/w;. c. the dispersing cum wetting agent is selected from the group comprising proprietary blend of phosphate ester and sodium naphthalene sulfonate formaldehyde condensate, highly sulfonation and low molecular weight kraft lignin polymer, sodium salt of aromatic ring surfactant, ammonium salt of aromatic ring surfactant, sodium salt of naphthalene sulphonic acid condensation, proprietary blend of anionic surfactant, sodium methyl oleoyl taurate, tristyrylphenol ethoxylate phosphate ester or a combination thereof and present in an amount in the range from 2-7% w/w; d. the safener is mefenpyr-diethyl present in an amount in the range from 0.01 to 2% w/w; e. the defoamer is polydimethylsiloxane antifoam emulsion present in an amount in the range from 0.01 to 1% w/w; f. the biocide/preservative is selected from the group comprising 20% aqueous dipropyleneglycol solution of 1,2- benzisothiazolin-3-one, formaldehyde, isothiazolinone or a combination thereof and present in an amount in the range from 0.01 to 1% w/w; g. the viscosity modifier is selected from the group comprising xanthan gum (2% solution), guar gum and present in an amount in the range from 5-15% w/w; h. the anti-settling agent is selected from the group comprising precipitated silica, organic bentonite, polyolefin particles and fumed silica and present in an amount in the range from 1.5 to 3.5% w/w; i. the filler is selected from the group comprising, silica, sodium bicarbonate, china clay, lactose, bentonite clay, kaolin, diatomaceous earth or a combination thereof and present in an amount quantity sufficient; and j. the diluent is demineralised water and present in an amount quantity sufficient.